Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

English (EN)·Polski (PL)·Yкраїнський (UK)
Przejdź do strony domowej biblioteki Centralna Biblioteka Wojskowa Link otwiera się w nowym oknie Logo biblioteki Prolib Integro - strona głównaCentralna Biblioteka Wojskowa

Wyszukujesz frazę "lattice" wg kryterium: Temat

  Lista filtrów

Dostawca treści

Wyrównaj
Wyświetlanie 1-100 z 231
Tytuł:
Classification systems and their lattice
Autorzy:
Radeleczki, Sándor
Powiązania:
https://bibliotekanauki.pl/articles/729009.pdf
Data publikacji:
2002
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
concept lattice
CJ-generated complete lattice
atomistic complete lattice
(independent) classification system
classification lattice
box lattice
Opis:
We define and study classification systems in an arbitrary CJ-generated complete lattice L. Introducing a partial order among the classification systems of L, we obtain a complete lattice denoted by Cls(L). By using the elements of the classification systems, another lattice is also constructed: the box lattice B(L) of L. We show that B(L) is an atomistic complete lattice, moreover Cls(L)=Cls(B(L)). If B(L) is a pseudocomplemented lattice, then every classification system of L is independent and Cls(L) is a partition lattice.
Źródło:
Discussiones Mathematicae - General Algebra and Applications; 2002, 22, 2; 167-181
1509-9415
Pojawia się w:
Discussiones Mathematicae - General Algebra and Applications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On duality of submodule lattices
Autorzy:
Czédli, Gábor
Takách, Géza
Powiązania:
https://bibliotekanauki.pl/articles/728870.pdf
Data publikacji:
2000
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
submodule lattice
lattice identity
duality
Opis:
An elementary proof is given for Hutchinson's duality theorem, which states that if a lattice identity λ holds in all submodule lattices of modules over a ring R with unit element then so does the dual of λ.
Źródło:
Discussiones Mathematicae - General Algebra and Applications; 2000, 20, 1; 43-49
1509-9415
Pojawia się w:
Discussiones Mathematicae - General Algebra and Applications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On some finite groupoids with distributive subgroupoid lattices
Autorzy:
Pióro, Konrad
Powiązania:
https://bibliotekanauki.pl/articles/729063.pdf
Data publikacji:
2002
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
groupoid
subgroupoid lattice
distributive lattice
Opis:
The aim of the paper is to show that if S(G) is distributive, and also G satisfies some additional condition, then the union of any two subgroupoids of G is also a subgroupoid (intuitively, G has to be in some sense a unary algebra).
Źródło:
Discussiones Mathematicae - General Algebra and Applications; 2002, 22, 1; 25-31
1509-9415
Pojawia się w:
Discussiones Mathematicae - General Algebra and Applications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Decomposition of Congruence Modular Algebras into Atomic, Atomless Locally Uniform and Anti-Uniform Parts
Autorzy:
Staruch, Bogdan
Staruch, Bożena
Powiązania:
https://bibliotekanauki.pl/articles/749904.pdf
Data publikacji:
2016
Wydawca:
Uniwersytet Łódzki. Wydawnictwo Uniwersytetu Łódzkiego
Tematy:
universal algebra
algebraic lattice
congruence lattice
atomic lattice
modular lattice
uniform lattice
subdirect product
star-product
decomposition of algebra
Opis:
We describe here a special subdirect decomposition of algebras with modular congruence lattice. Such a decomposition (called a star-decomposition) is based on the properties of the congruence lattices of algebras. We consider four properties of lattices: atomic, atomless, locally uniform and anti-uniform. In effect, we describe a star-decomposition of a given algebra with modular congruence lattice into two or three parts associated to these properties.
Źródło:
Bulletin of the Section of Logic; 2016, 45, 3/4
0138-0680
2449-836X
Pojawia się w:
Bulletin of the Section of Logic
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On a complete lattice of retracts of a free monoid generated by three elements
Autorzy:
Foryś, W.
Powiązania:
https://bibliotekanauki.pl/articles/255748.pdf
Data publikacji:
2008
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
free monoid
retract
lattice
complete lattice
Opis:
We prove that the family of retracts of a free monoid generated by three elements, partially ordered with respect to the inclusion, is a complete lattice.
Źródło:
Opuscula Mathematica; 2008, 28, 2; 123-127
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Quasiorder lattices are five-generated
Autorzy:
Kulin, Júlia
Powiązania:
https://bibliotekanauki.pl/articles/728856.pdf
Data publikacji:
2016
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
quasiorder lattice
preorder lattice
accessible cardinal
Opis:
A quasiorder (relation), also known as a preorder, is a reflexive and transitive relation. The quasiorders on a set A form a complete lattice with respect to set inclusion. Assume that A is a set such that there is no inaccessible cardinal less than or equal to |A|; note that in Kuratowski's model of ZFC, all sets A satisfy this assumption. Generalizing the 1996 result of Ivan Chajda and Gábor Czéedli, also Tamás Dolgos' recent achievement, we prove that in this case the lattice of quasiorders on A is five-generated, as a complete lattice.
Źródło:
Discussiones Mathematicae - General Algebra and Applications; 2016, 36, 1; 59-70
1509-9415
Pojawia się w:
Discussiones Mathematicae - General Algebra and Applications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Cardinalities of lattices of topologies of unars and some related topics
Autorzy:
Kartashova, Anna
Powiązania:
https://bibliotekanauki.pl/articles/728762.pdf
Data publikacji:
2001
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
unar
lattice of topologies
lattice of congruences
Opis:
In this paper we find cardinalities of lattices of topologies of uncountable unars and show that the lattice of topologies of a unar cannor be countably infinite. It is proved that under some finiteness conditions the lattice of topologies of a unar is finite. Furthermore, the relations between the lattice of topologies of an arbitrary unar and its congruence lattice are established.
Źródło:
Discussiones Mathematicae - General Algebra and Applications; 2001, 21, 2; 129-137
1509-9415
Pojawia się w:
Discussiones Mathematicae - General Algebra and Applications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Finite orders and their minimal strict completion lattices
Autorzy:
Bordalo, Gabriela
Monjardet, Bernard
Powiązania:
https://bibliotekanauki.pl/articles/728964.pdf
Data publikacji:
2003
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
atomistic lattice
join-irreducible element
distributive lattice
modular lattice
lower semimodular lattice
Dedekind-MacNeille completion
strict completion
weak order.
Opis:
Whereas the Dedekind-MacNeille completion D(P) of a poset P is the minimal lattice L such that every element of L is a join of elements of P, the minimal strict completion D(P)∗ is the minimal lattice L such that the poset of join-irreducible elements of L is isomorphic to P. (These two completions are the same if every element of P is join-irreducible). In this paper we study lattices which are minimal strict completions of finite orders. Such lattices are in one-to-one correspondence with finite posets. Among other results we show that, for every finite poset P, D(P)∗ is always generated by its doubly-irreducible elements. Furthermore, we characterize the posets P for which D(P)∗ is a lower semimodular lattice and, equivalently, a modular lattice.
Źródło:
Discussiones Mathematicae - General Algebra and Applications; 2003, 23, 2; 85-100
1509-9415
Pojawia się w:
Discussiones Mathematicae - General Algebra and Applications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
B-almost distributive fuzzy lattice
Autorzy:
Assaye, Berhanu
Alemneh, Mihret
Tefera, Gerima
Powiązania:
https://bibliotekanauki.pl/articles/749988.pdf
Data publikacji:
2018
Wydawca:
Uniwersytet Łódzki. Wydawnictwo Uniwersytetu Łódzkiego
Tematy:
almost distributive lattice
Heyting almost distributive lattice (HADL)
B-almost distributive lattice
principal ideals of an almost distributive lattice
Opis:
The paper introduces the concept of B-Almost distributive fuzzy lattice (BADFL) in terms of its principal ideal fuzzy lattice. Necessary and sufficient conditions for an ADFL to become a B-ADFL are investigated. We also prove the equivalency of B-algebra and B-fuzzy algebra. In addition, we extend PSADL to PSADFL and prove that B-ADFL implies PSADFL.
Źródło:
Bulletin of the Section of Logic; 2018, 47, 3
0138-0680
2449-836X
Pojawia się w:
Bulletin of the Section of Logic
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Distributivity of bounded lattices with sectionally antitone involutions
Autorzy:
Chajda, Ivan
Powiązania:
https://bibliotekanauki.pl/articles/729093.pdf
Data publikacji:
2005
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
sectionally antitone involution
bounded lattice
distributive lattice
MV-algebra
Opis:
We present a simple condition under which a bounded lattice L with sectionally antitone involutions becomes an MV-algebra. In thiscase, L is distributive. However, we get a criterion characterizingdistributivity of L in terms of antitone involutions only.
Źródło:
Discussiones Mathematicae - General Algebra and Applications; 2005, 25, 2; 155-163
1509-9415
Pojawia się w:
Discussiones Mathematicae - General Algebra and Applications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On lattice-ordered monoids
Autorzy:
Jasem, Milan
Powiązania:
https://bibliotekanauki.pl/articles/728966.pdf
Data publikacji:
2003
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
lattice-ordered monoid
normal lattice-ordered monoid
dually residuated lattice-ordered semigroup
direct decomposition
polar
Opis:
In the paper lattice-ordered monoids and specially normal lattice-ordered monoids which are a generalization of dually residuated lattice-ordered semigroups are investigated. Normal lattice-ordered monoids are metricless normal lattice-ordered autometrized algebras. It is proved that in any lattice-ordered monoid A, a ∈ A and na ≥ 0 for some positive integer n imply a ≥ 0. A necessary and sufficient condition is found for a lattice-ordered monoid A, such that the set I of all invertible elements of A is a convex subset of A and A¯ ⊆ I, to be the direct product of the lattice-ordered group I and a lattice-ordered semigroup P with the least element 0.
Źródło:
Discussiones Mathematicae - General Algebra and Applications; 2003, 23, 2; 101-114
1509-9415
Pojawia się w:
Discussiones Mathematicae - General Algebra and Applications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Characterization of Birkhoff’s Conditions by Means of Cover-Preserving and Partially Cover-Preserving Sublattices
Autorzy:
Łazarz, Marcin
Powiązania:
https://bibliotekanauki.pl/articles/749906.pdf
Data publikacji:
2016
Wydawca:
Uniwersytet Łódzki. Wydawnictwo Uniwersytetu Łódzkiego
Tematy:
Birkhoff’s conditions
semimodularity conditions
modular lattice
discrete lattices
upper continuous lattice
strongly atomic lattice
cover-preserving sublattice
cell
4-cell lattice
Opis:
In the paper we investigate Birkhoff’s conditions (Bi) and (Bi*). We prove that a discrete lattice L satisfies the condition (Bi) (the condition (Bi*)) if and only if L is a 4-cell lattice not containing a cover-preserving sublattice isomorphic to the lattice S*7 (the lattice S7). As a corollary we obtain a well known result of J. Jakub´ık from [6]. Furthermore, lattices S7 and S*7 are considered as so-called partially cover-preserving sublattices of a given lattice L, S7 ≪ L and S7 ≪ L, in symbols. It is shown that an upper continuous lattice L satisfies (Bi*) if and only if L is a 4-cell lattice such that S7 ≪/ L. The final corollary is a generalization of Jakubík’s theorem for upper continuous and strongly atomic lattices. Keywords: Birkhoff’s conditions, semimodularity conditions, modular lattice, discrete lattices, upper continuous lattice, strongly atomic lattice, cover-preserving sublattice, cell, 4-cell lattice.  
Źródło:
Bulletin of the Section of Logic; 2016, 45, 3/4
0138-0680
2449-836X
Pojawia się w:
Bulletin of the Section of Logic
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Distribution of lattice points on hyperbolic surfaces
Autorzy:
Lev, Vsevolod
Powiązania:
https://bibliotekanauki.pl/articles/1391179.pdf
Data publikacji:
1996
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
lattice
hyperbolic surface
Opis:
Let two lattices $Λ', Λ'' ⊂ ℝ^s$ have the same number of points on each hyperbolic surface $|x₁...x_s| = C$. We investigate the case when Λ', Λ'' are sublattices of $ℤ^s$ of the same prime index and show that then Λ' and Λ'' must coincide up to renumbering the coordinate axes and changing their directions.
Źródło:
Acta Arithmetica; 1996, 75, 1; 85-95
0065-1036
Pojawia się w:
Acta Arithmetica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On varieties of orgraphs
Autorzy:
Haviar, Alfonz
Monoszová, Gabriela
Powiązania:
https://bibliotekanauki.pl/articles/743478.pdf
Data publikacji:
2001
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
orgraph
variety
lattice
Opis:
In this paper we investigate varieties of orgraphs (that is, oriented graphs) as classes of orgraphs closed under isomorphic images, suborgraph identifications and induced suborgraphs, and we study the lattice of varieties of tournament-free orgraphs.
Źródło:
Discussiones Mathematicae Graph Theory; 2001, 21, 2; 207-221
2083-5892
Pojawia się w:
Discussiones Mathematicae Graph Theory
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Some characterizations of pseudo-BL-chains
Autorzy:
Walendziak, Andrzej
Wojciechowska-Rysiawa, Magdalena
Powiązania:
https://bibliotekanauki.pl/articles/744864.pdf
Data publikacji:
2011
Wydawca:
Polskie Towarzystwo Matematyczne
Tematy:
Pseudo-BL-algebra (-chain)
Lattice
Join irreducible element
Stone lattice
Opis:
Pseudo-BL-chains are linearly ordered pseudo-BL-algebras. Characterizations of them in terms of concepts of lattice theory are given.
Źródło:
Commentationes Mathematicae; 2011, 51, 2
0373-8299
Pojawia się w:
Commentationes Mathematicae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Balanced d-lattices are complemented
Autorzy:
Goldstern, Martin
Ploščica, Miroslav
Powiązania:
https://bibliotekanauki.pl/articles/729051.pdf
Data publikacji:
2002
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
balanced congruence
balanced lattice
d-lattice
prime ideal
maximal ideal
Opis:
We characterize d-lattices as those bounded lattices in which every maximal filter/ideal is prime, and we show that a d-lattice is complemented iff it is balanced iff all prime filters/ideals are maximal.
Źródło:
Discussiones Mathematicae - General Algebra and Applications; 2002, 22, 1; 33-37
1509-9415
Pojawia się w:
Discussiones Mathematicae - General Algebra and Applications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mixing in a stirred vessel. A parallel implementation with lattice Boltzmann coloured particles model
Autorzy:
Misci, L.
Felici, M.
Powiązania:
https://bibliotekanauki.pl/articles/1964147.pdf
Data publikacji:
2005
Wydawca:
Politechnika Gdańska
Tematy:
lattice Boltzmann
parallel algorithm
Opis:
The main purpose of this paper is to present a new method for the study of single fluid mixing in a stirred vessel. The simulation has been realized with a parallel implementation of the Lattice Boltzmann coloured particles model. The mixing phenomenon is compared with the one derived with a Lagrangian approach.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2005, 9, 4; 449-459
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A contribution to dynamics of polyatomic lattices
Autorzy:
Rychlewska, J.
Szymczyk, J.
Woźniak, C.
Powiązania:
https://bibliotekanauki.pl/articles/279686.pdf
Data publikacji:
1999
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
lattice dynamics
continuum models
Opis:
Using a concept of internal degrees of freedom a new finite difference formulation of polyatomic lattice dynamics is proposed. A transition from the nonlocal equations of motion to the partly local and local ones as well as the possibility of reduction of internal degrees of freedom are shown.
Wprowadzając pojęcie wewnętrznych stopni swobody sformułowano nową różnicową postać dynamiki sieci złożonych. Pokazano przejście od równań nielokalnych do modeli częściowo i całkowicie lokalnych oraz zwrócono uwagę na możliwość wyrugowania wewnętrznych stopni swobody.
Źródło:
Journal of Theoretical and Applied Mechanics; 1999, 4; 799-807
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Congruences on pseudocomplemented semilattices
Autorzy:
Heleyová, Zuzana
Powiązania:
https://bibliotekanauki.pl/articles/728824.pdf
Data publikacji:
2000
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
pseudocomplemented semilattice
congruence lattice
p-algebra
Stone algebra
(relative) (Lₙ)-lattice
Opis:
It is known that congruence lattices of pseudocomplemented semilattices are pseudocomplemented [4]. Many interesting properties of congruences on pseudocomplemented semilattices were described by Sankappanavar in [4], [5], [6]. Except for other results he described congruence distributive pseudocomplemented semilattices [6] and he characterized pseudocomplemented semilattices whose congruence lattices are Stone, i.e. belong to the variety B₁ [5].
In this paper we give a partial solution to a more general question: Under what condition on a pseudocomplemented semilattice its congruence lattice is element of the variety Bₙ (n ≥ 2)?
In the last section we widen the Sankappanavar's result to obtain the description of pseudocomplemented semilattices with relative Stone congruence lattices. A partial solution of the description of pseudocomplemented semilattices with relative (Lₙ)-congruence lattices (n ≥ 2) is also given.
Źródło:
Discussiones Mathematicae - General Algebra and Applications; 2000, 20, 2; 219-231
1509-9415
Pojawia się w:
Discussiones Mathematicae - General Algebra and Applications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
PC-lattices: A Class of Bounded BCK-algebras
Autorzy:
Shoar, Sadegh Khosravi
Borzooei, Rajab Ali
Moradian, R.
Radfar, Atefe
Powiązania:
https://bibliotekanauki.pl/articles/749890.pdf
Data publikacji:
2018
Wydawca:
Uniwersytet Łódzki. Wydawnictwo Uniwersytetu Łódzkiego
Tematy:
PC-lattice
BCK-lattice
Involutory BCK-algebras
Bounded commutative BCK-algebras
Opis:
In this paper, we define the notion of PC-lattice, as a generalization of finite positive implicative BCK-algebras with condition (S) and bounded commutative BCK-algebras. We investiate some results for Pc-lattices being a new class of BCK-lattices. Specially, we prove that any Boolean lattice is a PC-lattice and we show that if X is a PC-lattice with condition S, then X is an involutory BCK-algebra if and only if X is a commutative BCK-algebra. Finally, we prove that any PC-lattice with condition (S) is a distributive BCK-algebra.  
Źródło:
Bulletin of the Section of Logic; 2018, 47, 1
0138-0680
2449-836X
Pojawia się w:
Bulletin of the Section of Logic
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Note on some Characterization of Distributive Lattices of Finite Length
Autorzy:
Łazarz, Marcin
Siemieńczuk, Krzysztof
Powiązania:
https://bibliotekanauki.pl/articles/749958.pdf
Data publikacji:
2015
Wydawca:
Uniwersytet Łódzki. Wydawnictwo Uniwersytetu Łódzkiego
Tematy:
distributive lattice
finite length
Opis:
Using known facts we give a simple characterization of the distributivity of lattices of finite length.
Źródło:
Bulletin of the Section of Logic; 2015, 44, 1-2
0138-0680
2449-836X
Pojawia się w:
Bulletin of the Section of Logic
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study of continuous phase transition with Toom cellular automata
Autorzy:
Makowiec, D.
Powiązania:
https://bibliotekanauki.pl/articles/1941716.pdf
Data publikacji:
2000
Wydawca:
Politechnika Gdańska
Tematy:
equilibrium lattice model
equilibrium lattice systems
critical components
Gibbsian measures
Ising model
Opis:
The heuristic proof, based on computer simulation investigations, is presented that though stationary Toom cellular automata exhibit many features which are characteristic for an equilibrium system (e.g. rapid change in the order parameter, when noise is fine tuned, or slow decay of the two point correlation function), the stationary state is not Gibbsian. It means that it is impossible to define energy on the microscopic level in such a way that the dynamic system becomes representative of some equilibrium lattice model. Moreover, properties on the coarse-grained level: fluctuations, seem to be distinct from the corresponding ones of the Ising model.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2000, 4, 1; 19-31
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Isomorphisms of direct products of lattice-ordered groups
Autorzy:
Jakubík, Ján
Powiązania:
https://bibliotekanauki.pl/articles/728908.pdf
Data publikacji:
2004
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
Lattice-ordered group
direct product
Specker lattice-ordered group
orthogonal σ-completeness
Opis:
In this paper we investigate sufficient conditions for the validity of certain implications concerning direct products of lattice-ordered groups.
Źródło:
Discussiones Mathematicae - General Algebra and Applications; 2004, 24, 1; 43-52
1509-9415
Pojawia się w:
Discussiones Mathematicae - General Algebra and Applications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Congruence lattices of free lattices in non-distributive varieties
Autorzy:
Ploščica, Miroslav
Tůma, Jiří
Wehrung, Friedrich
Powiązania:
https://bibliotekanauki.pl/articles/966045.pdf
Data publikacji:
1998
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
diamond
congruence splitting lattice
Kuratowski's Theorem
Uniform Refinement Property
congruence lattice
pentagon
Źródło:
Colloquium Mathematicum; 1998, 76, 2; 269-278
0010-1354
Pojawia się w:
Colloquium Mathematicum
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Simulation of two dimensional photonic band gaps
Autorzy:
Dissanayake, S. E.
Wijewardena Gamalath, K. A. I. L.
Powiązania:
https://bibliotekanauki.pl/articles/411904.pdf
Data publikacji:
2014
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Photonic crystal
square lattice
triangular lattice
honeycomb lattice
plane wave expansion
mode field distribution
GaAs
dielectric kontrast
filling fraction
gap maps
Opis:
The plane wave expansion method was implemented in modelling and simulating the band structures of two dimensional photonic crystals with square, triangular and honeycomb lattices with circular, square and hexagonal dielectric rods and air holes. Complete band gaps were obtained for square lattice of square GaAs rods and honeycomb lattice of circular and hexagonal GaAs rods as well as triangular lattice of circular and hexagonal air holes in GaAs whereas square lattice of square or circular air holes in a dielectric medium ε = 18 gave complete band gaps. The variation of these band gaps with dielectric contrast and filling factor gave the largest gaps for all configurations for a filling fraction around 0.1.The gap maps presented indicated that TM gaps are more favoured by dielectric rods while TE gaps are favoured by air holes. The geometrical gap maps operating at telecommunication wavelength λ = 1.55 m showed that a complete band gap can be achieved for triangular lattice with circular and hexagonal air holes in GaAs and for honeycomb lattice of circular GaAs rods.
Źródło:
International Letters of Chemistry, Physics and Astronomy; 2014, 5; 58-88
2299-3843
Pojawia się w:
International Letters of Chemistry, Physics and Astronomy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On interval decomposition lattices
Autorzy:
Foldes, Stephan
Radeleczki, Sándor
Powiązania:
https://bibliotekanauki.pl/articles/728916.pdf
Data publikacji:
2004
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
interval
closure system
modular decomposition
semimodular lattice
partition lattice
strong set
lexicographic sum
Opis:
Intervals in binary or n-ary relations or other discrete structures generalize the concept of interval in an ordered set. They are defined abstractly as closed sets of a closure system on a set V, satisfying certain axioms. Decompositions are partitions of V whose blocks are intervals, and they form an algebraic semimodular lattice. Lattice-theoretical properties of decompositions are explored, and connections with particular types of intervals are established.
Źródło:
Discussiones Mathematicae - General Algebra and Applications; 2004, 24, 1; 95-114
1509-9415
Pojawia się w:
Discussiones Mathematicae - General Algebra and Applications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A reduction theorem for ring varieties whose subvariety lattice is distributive
Autorzy:
Volkov, Mikhail
Powiązania:
https://bibliotekanauki.pl/articles/729065.pdf
Data publikacji:
2010
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
variety of rings
subvariety lattice
distributive lattice
torsion-bounded variety
Mal'tsev product
Opis:
We prove a theorem (for arbitrary ring varieties and, in a stronger form, for varieties of associative rings) which basically reduces the problem of a description of varieties with distributive subvariety lattice to the case of algebras over a finite prime field.
Źródło:
Discussiones Mathematicae - General Algebra and Applications; 2010, 30, 1; 119-132
1509-9415
Pojawia się w:
Discussiones Mathematicae - General Algebra and Applications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Irredundant Decomposition of Algebras into One-Dimensional Factors
Autorzy:
Staruch, Bogdan
Powiązania:
https://bibliotekanauki.pl/articles/750002.pdf
Data publikacji:
2016
Wydawca:
Uniwersytet Łódzki. Wydawnictwo Uniwersytetu Łódzkiego
Tematy:
universal algebra
algebraic lattice
congruence lattice
uniform lattice
dimension of algebra
one-dimensional algebra
subdirect product
star-product
decomposition of algebra
Opis:
We introduce a notion of dimension of an algebraic lattice and, treating such a lattice as the congruence lattice of an algebra, we introduce the dimension of an algebra, too. We define a star-product as a special kind of subdirect product. We obtain the star-decomposition of algebras into one-dimensional factors, which generalizes the known decomposition theorems e.g. for Abelian groups, linear spaces, Boolean algebras.
Źródło:
Bulletin of the Section of Logic; 2016, 45, 3/4
0138-0680
2449-836X
Pojawia się w:
Bulletin of the Section of Logic
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The fractal characteristics of lattice media. Part II.
Autorzy:
Marciniak, A.
Fijolek, A.
Kwiecien, S.
Podgorski, J.
Powiązania:
https://bibliotekanauki.pl/articles/24485.pdf
Data publikacji:
1996
Wydawca:
Polska Akademia Nauk. Instytut Agrofizyki PAN
Tematy:
fractal analysis
lattice medium
dimension
Źródło:
International Agrophysics; 1996, 10, 4
0236-8722
Pojawia się w:
International Agrophysics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Three dimensional photonic crystals
Autorzy:
Dissanayake, S. E.
Wijewardena Gamalath, K. A. I. L.
Powiązania:
https://bibliotekanauki.pl/articles/1194049.pdf
Data publikacji:
2015
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Fcc lattice and diamond lattice
GaAs
Photonic crystal
dielectric contrast
filling fraction
plane wave expansion
Opis:
The plane wave expansion method was implemented in modelling and simulating the band structures of three dimensional photonic crystals with FCC lattice formed from air spheres drilled in GaAs and diamond lattice formed by GaAs spheres drilled in air. Both these structures lead to a complete band gap not allowing EM waves with the frequency of the band gap to propagate through the crystal in any direction. Diamond lattice photonic crystal has a complete band gap for a wider range of filling fraction than FCC photonic crystal and also it has a wider band gap width.
Źródło:
World Scientific News; 2015, 12; 12-23
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wykorzystanie metody lattice-Boltzmann do symulacji mikroprzepływów w kanałach układów lab on a chip
Application of lattice-Boltzmann method in microflow simulation in a lab-on-a-chip microchannels systems
Autorzy:
Szafran, R.
Tomczak, T.
Powiązania:
https://bibliotekanauki.pl/articles/2072151.pdf
Data publikacji:
2013
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
modelowanie matematyczne
mikroprzepływy
lab-on-a-chip
lattice-Boltzmann
DFD
numerical modeling
microflows
lattice Boltzmann
Opis:
W pracy zostały przedstawione wyniki badań doświadczalnych i symulacji komputerowych metodą Lattice-Boltzmann przepływów płynów komórkowych w mikrokanałach układu lab-on-a-chip (LOC). Symulacje LBM przeprowadzono dla geometrii 2D (model 2DQ9), co wpłynęło na skrócenie czasu obliczeń, w istotny sposób zwiększając jednak ich błąd, który wahał się w szerokich granicach od 15 do ponad 100%.
Experimental and computer simulation results using the Lattice-Boltzmann method for fluid flows in microchannels of the lab-on-a-chip (LOC) device are presented in the paper. LBM simulations were performed for 2D geometry (2DQ9 model), allowing the shortening of simulation time but signifi¬cantly increasing the calculation error. The calculation error of fluid mean velocity ranged from 15 to over 100%.
Źródło:
Inżynieria i Aparatura Chemiczna; 2013, 6; 568--569
0368-0827
Pojawia się w:
Inżynieria i Aparatura Chemiczna
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Minimal bounded lattices with an antitone involution the complemented elements of which do not form a sublattice
Autorzy:
Chajda, Ivan
Länger, Helmut
Powiązania:
https://bibliotekanauki.pl/articles/728776.pdf
Data publikacji:
2008
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
bounded lattice
antitone involution
complemented element
Opis:
Bounded lattices with an antitone involution the complemented elements of which do not form a sublattice must contain two complemented elements such that not both their join and their meet are complemented. We distinguish (up to symmetry) eight cases and in each of these cases we present such a lattice of minimal cardinality.
Źródło:
Discussiones Mathematicae - General Algebra and Applications; 2008, 28, 2; 251-259
1509-9415
Pojawia się w:
Discussiones Mathematicae - General Algebra and Applications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On ideals of a skew lattice
Autorzy:
Costa, João Pita
Powiązania:
https://bibliotekanauki.pl/articles/728981.pdf
Data publikacji:
2012
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
noncommutative lattice
skew lattice
band of semigroups
ideals
coset structure
Green's relations
skew Boolean algebras
Opis:
Ideals are one of the main topics of interest when it comes to the study of the order structure of an algebra. Due to their nice properties, ideals have an important role both in lattice theory and semigroup theory. Two natural concepts of ideal can be derived, respectively, from the two concepts of order that arise in the context of skew lattices. The correspondence between the ideals of a skew lattice, derived from the preorder, and the ideals of its respective lattice image is clear. Though, skew ideals, derived from the partial order, seem to be closer to the specific nature of skew lattices. In this paper we review ideals in skew lattices and discuss the intersection of this with the study of the coset structure of a skew lattice.
Źródło:
Discussiones Mathematicae - General Algebra and Applications; 2012, 32, 1; 5-21
1509-9415
Pojawia się w:
Discussiones Mathematicae - General Algebra and Applications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Congruence submodularity
Autorzy:
Chajda, Ivan
Halaš, Radomír
Powiązania:
https://bibliotekanauki.pl/articles/728993.pdf
Data publikacji:
2002
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
congruence lattice
modularity
congruence k-submodularity
Opis:
We present a countable infinite chain of conditions which are essentially weaker then congruence modularity (with exception of first two). For varieties of algebras, the third of these conditions, the so called 4-submodularity, is equivalent to congruence modularity. This is not true for single algebras in general. These conditions are characterized by Maltsev type conditions.
Źródło:
Discussiones Mathematicae - General Algebra and Applications; 2002, 22, 2; 131-139
1509-9415
Pojawia się w:
Discussiones Mathematicae - General Algebra and Applications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Investigation on Irreversible Expansion of 1,3,5-Triamino-2,4,6-trinitrobenzene Cylinder
Autorzy:
Sun, J.
Kang, B.
Zhang, H.
Liu, Y.
Xia, Y.
Yao, Y.
Liu, X.
Powiązania:
https://bibliotekanauki.pl/articles/357936.pdf
Data publikacji:
2011
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
TATB
irreversible expansion
XRD
lattice parameters
Opis:
In this study, the irreversible expansion of TATB cylinder is investigated. No evident variation of the lattice parameters is observed on TATB crystal. The density of TATB powder decreases by only about 0.02% after it suffered from thermal cycling process at the range from -54 C to 74 C, while the density of TATB cylinder decreases by about 1.0%. It is suggested that the density variation of TATB powder has little contribution to the density decrease of TATB cylinder. Therefore, the increasing interstices between TATB powder originated from the thermal cycling should be responsible to the irreversible expansion of TATB cylinder.
Źródło:
Central European Journal of Energetic Materials; 2011, 8, 1; 69-79
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Many Faces of Lattice Tolerances
Autorzy:
Grygiel, Joanna
Powiązania:
https://bibliotekanauki.pl/articles/750048.pdf
Data publikacji:
2019
Wydawca:
Uniwersytet Łódzki. Wydawnictwo Uniwersytetu Łódzkiego
Tematy:
lattice
tolerance
congruence
covering system
gluing
Opis:
Our aim is to overview and discuss some of the most popular approaches to the notion of a tolerance relation in algebraic structures with the special emphasis on lattices.
Źródło:
Bulletin of the Section of Logic; 2019, 48, 4
0138-0680
2449-836X
Pojawia się w:
Bulletin of the Section of Logic
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A note on joins of additive hereditary graph properties
Autorzy:
Drgas-Burchardt, Ewa
Powiązania:
https://bibliotekanauki.pl/articles/743593.pdf
Data publikacji:
2006
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
hereditary property
lattice of additive hereditary graph properties
minimal forbidden subgraph family
join in the lattice
Opis:
Let $L^a$ denote a set of additive hereditary graph properties. It is a known fact that a partially ordered set $(L^a, ⊆ )$ is a complete distributive lattice. We present results when a join of two additive hereditary graph properties in $(L^a, ⊆ )$ has a finite or infinite family of minimal forbidden subgraphs.
Źródło:
Discussiones Mathematicae Graph Theory; 2006, 26, 3; 413-418
2083-5892
Pojawia się w:
Discussiones Mathematicae Graph Theory
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On the new characteristics of Miller indices for centered lattices
Autorzy:
Michalski, E.
Powiązania:
https://bibliotekanauki.pl/articles/200839.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Miller indices
families of lattice planes
reciprocal lattice
centered lattice
transformations in crystallography
Laue indices of Bragg reflections
integral systematic absences
transformacje
krystalografia
siatka Bragga
Opis:
This work proposes and justifies a clarification of the description of the crystal structure with the use of centered lattices, and concerns also the following: (1) the graphical and analytical criterion for the existence of lattice planes, described by selected Miller indices, (2) the correct way to use the parametric equation of families of planes, (3) “geometric derivation of the integral reflection conditions” and “Laue indices of Bragg peaks versus Miller indices of families of lattice planes”, (4) the characteristics of Miller indices describing nodes of reciprocal lattices for centered direct lattices, (5) the characteristics of Miller indices describing the faces of single crystals and also (6) the characteristics of the information included in Miller indices. Reciprocal lattice nodes associated with families of lattice planes in direct lattices do not form the centered lattices in the reciprocal space themselves. The centered lattices in reciprocal space are created by points with coordinates equal to the Laue indices of Bragg reflections, which are allowed by the integral systematic absences. Parts of them are not associated with any of the direct lattice planes.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2018, 66, 4; 529-538
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Method for calculating performance characteristics of hydrokinetic turbines
Autorzy:
Góralczyk, A.
Chaja, P.
Adamkowski, A.
Powiązania:
https://bibliotekanauki.pl/articles/1934038.pdf
Data publikacji:
2011
Wydawca:
Politechnika Gdańska
Tematy:
hydrokinetic turbines
Vortex-Lattice Method
performance characteristics
Opis:
This paper presents a numerical algorithm and its computer implementation (program) developed to determine the operational characteristics of axial flow hydrokinetic turbines. The program is based on the Vortex-Lattice Method (VLM), which proved useful for predicting hydrodynamic characteristics of screw propellers. In order to validate the software, we carried out a series of experiments on a laboratory test stand at the Institute of Fluid-Flow Machinery at the Polish Academy of Sciences (IMP PAN) in Gdansk. From the practical point of view, the agreement between the calculated and experimental results was satisfactory. Therefore, the developed numerical method can be a useful tool for the analysis of operating conditions and in the design of hydrokinetic turbines.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2011, 15, 1; 43-57
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The influence of low density behaviour of state equation on lattice inverted pair potential for lead
Autorzy:
Laskowski, R.
Chybicki, M.
Powiązania:
https://bibliotekanauki.pl/articles/1954520.pdf
Data publikacji:
1999
Wydawca:
Politechnika Gdańska
Tematy:
lattice inversion technique
pair potential
molecular simulations
Opis:
A pair potential for lead (Pb) is extracted from the ab-initio energy-volume data using the lattice inversion procedure of Carlsson and co-workers [Phil. Mag. 41 (1980), p. 241]. Because of a limited accuracy of the ab-initio techniques, we extrapolate the energy-volume data for low-density systems with suitable analytical tail functions. We discuss the dependence of the molecular dynamics (MD) simulation structural results and the elastic modules on the choice of the cohesive energy tail function. The MD-simulated radial distribution functions (RDFs), obtained for several energy tails, in several temperatures are discussed.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 1999, 3, 3; 303-312
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An equational basis in four variables for the three-element tournament
Autorzy:
Grätzer, G.
Kisielewicz, A.
Wolk, B.
Powiązania:
https://bibliotekanauki.pl/articles/967600.pdf
Data publikacji:
1992
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
weakly associative lattice
tournament
identity
equational basis
Źródło:
Colloquium Mathematicum; 1992, 63, 1; 41-44
0010-1354
Pojawia się w:
Colloquium Mathematicum
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Hypersubstitutions in orthomodular lattices
Autorzy:
Chajda, Ivan
Länger, Helmut
Powiązania:
https://bibliotekanauki.pl/articles/728780.pdf
Data publikacji:
2001
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
hypersubstitution
proper hypersubstitution
orthomodular lattice
absorption algebra
Opis:
It is shown that in the variety of orthomodular lattices every hypersubstitution respecting all absorption laws either leaves the lattice operations unchanged or interchanges join and meet. Further, in a variety of lattices with an involutory antiautomorphism a semigroup generated by three involutory hypersubstitutions is described.
Źródło:
Discussiones Mathematicae - General Algebra and Applications; 2001, 21, 1; 83-92
1509-9415
Pojawia się w:
Discussiones Mathematicae - General Algebra and Applications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On M-operators of q-lattices
Autorzy:
Halaš, Radomír
Powiązania:
https://bibliotekanauki.pl/articles/729005.pdf
Data publikacji:
2002
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
(complete) q-lattice
closure operator
M-operator
Opis:
It is well known that every complete lattice can be considered as a complete lattice of closed sets with respect to appropriate closure operator. The theory of q-lattices as a natural generalization of lattices gives rise to a question whether a similar statement is true in the case of q-lattices. In the paper the so-called M-operators are introduced and it is shown that complete q-lattices are q-lattices of closed sets with respect to M-operators.
Źródło:
Discussiones Mathematicae - General Algebra and Applications; 2002, 22, 2; 119-129
1509-9415
Pojawia się w:
Discussiones Mathematicae - General Algebra and Applications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Square Ising Nanowire on the Bethe Lattice
Autorzy:
Albayrak, E.
Powiązania:
https://bibliotekanauki.pl/articles/1032327.pdf
Data publikacji:
2017-06
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
Bethe lattice
nanowire
phase diagrams
magnetization
tricritical
Opis:
The square-type nanowire is simulated on the Bethe lattice by using the core-shell structure consisting of the Ising spins. A nanoparticle is formed by placing a spin to the center and four others to the corners of a square. Then, each nanoparticle is combined with two neighboring ones with a perfect alignment of the squares to form the nanowire. Only nearest-neighbor spin interactions, either ferromagnetic or antiferromagnetic type, are allowed. The phase diagrams are calculated by studying the thermal variations of magnetizations for various values of bilinear interactions. It is found that the model gives both second- and first-order phase transitions in addition to the tricritical points and compensation temperatures.
Źródło:
Acta Physica Polonica A; 2017, 131, 6; 1470-1473
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An Energy Efficient QAM Modulation with Multidimensional Signal Constellation
Autorzy:
Markiewicz, T. G.
Powiązania:
https://bibliotekanauki.pl/articles/227049.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
communication system
QAM modulation
lattice
multidimensional constellations
Opis:
Packing constellations points in higher dimensions, the concept of multidimensional modulation exploits the idea drawn from geometry for searching dense sphere packings in a given dimension, utilising it to minimise the average energy of the underlying constellations. The following work analyses the impact of spherical shaping of the constellations bound instead of the traditional, hyper-cubical bound. Balanced constellation schemes are obtained with the N-dimensional simplex merging algorithm. The performance of constellations of dimensions 2, 4 and 6 is compared to the performance of QAM modulations of equivalent throughputs in the sense of bits transmitted per complex (twodimensional) symbols. The considered constellations give an approximately 0.7 dB to 1 dB gain in terms of BER over a standard QAM modulation.
Źródło:
International Journal of Electronics and Telecommunications; 2016, 62, 2; 159-165
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Lightweight plastic gear body using gyroid structure for additive manufacturing
Autorzy:
Nguyen, Loc Huu
Nguyen, Khoi Thanh
Powiązania:
https://bibliotekanauki.pl/articles/2171773.pdf
Data publikacji:
2022
Wydawca:
Wrocławska Rada Federacji Stowarzyszeń Naukowo-Technicznych
Tematy:
plastic
spur gear lattice
gyroid
additive manufacturing
Opis:
Nowadays, plastic gears are more commonly used. The Triply Periodic Minimal Surfaces (TPMS) structure can perfect the design to reduce weight but still achieve the desired workability criteria. It can also be adjusted more easily and scientifically than the empirical structure optimization based on experience. Currently, the fabrication of gears with complex internal structures such as TPMS is possible thanks to 3D printing technology. This study investigates the mechanical properties of a TPMS structure when applied to Polyetheretherketone (PEEK) plastic gears. The research content includes displacement, deformation, and Von-mises stress to evaluate the stiffness and strength of gears. The structure used to optimize the gear mass is the Gyroid structure, developed in the cylindrical cell map and studied in the paper. The goal of the research is to apply the Gyroid structure to optimize mass while still ensuring gear performance. This study not only offers new insight into the importance of the control variables for TPMS structures but also provides a mass lean process for gear designers. It uses experimental design methods to choose a suitable topology structure, and the final research result is a regression equation, which clearly shows the close relationship between the volume reduction and displacement with the specified control variables of the unit cell. From there, it is possible to determine the proper amount of material reduction while ensuring the working ability of the gear transmission.
Źródło:
Journal of Machine Engineering; 2022, 22, 4; 21--42
1895-7595
2391-8071
Pojawia się w:
Journal of Machine Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Lattice rotation definition and predicted textures of tensile and compression deformation
Autorzy:
Wroński, M.
Wierzbanowski, K.
Powiązania:
https://bibliotekanauki.pl/articles/352559.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
axisymmetric deformation
texture
lattice rotation
deformation models
Opis:
The problem of ambiguity in the definition of lattice rotation, used in plastic deformation models, is examined in this work. The geometry of tensile and compression deformation is considered. Two approaches to lattice rotation are considered: the classical definition (called also 'mathematical analysis) and the definition based on orientation preservation of specified directions/planes in the sample coordinates system. Similar study was already done by the present authors for the geometry of rolling deformation. It was shown that application of two rotation definitions enables to explain the appearance of two types of f. c. c. rolling textures: brass type and copper type textures. In the case of axisymmetric deformation the application of both definitions of lattice rotation leads to similar textures, but with different spread of their principal components.
Źródło:
Archives of Metallurgy and Materials; 2016, 61, 3; 1529-1536
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An efficient method of tortuosity estimation
Autorzy:
Sobieski, W.
Powiązania:
https://bibliotekanauki.pl/articles/38629876.pdf
Data publikacji:
2022
Wydawca:
Instytut Podstawowych Problemów Techniki PAN
Tematy:
porous media
tortuosity
streamlines
Lattice Boltzmann Method
Opis:
The paper presents a comparative analysis of tortuosity calculations in two types of 2D random geometries: with non-overlapping circles and with overlapping squares. Both geometries were converted to binary geometries with different resolution. Next, simulations involving the Lattice Boltzmann Method were performed to obtain velocity fields in a pore space. Based on the obtained velocity fields, Hydraulic tortuosity and streamline tortuosity were calculated, based on the obtained velocity fields, for all considered cases. Hydraulic tortuosity was calculated with the methodology proposed by Koponen et al., whereas streamline tortuosity was determined with the use of a new iterative algorithm. Two variants of the algorithm were proposed. Additionally, the obtained results were compared with selected formulas from the literature. The study demonstrated that calculations of streamlines exiting local inlet velocity maxima are a good alternative to calculations where all possible streamlines are taken into account. Computation time was significantly shorter and estimation quality was comparable.
Źródło:
Archives of Mechanics; 2022, 74, 1; 39-64
0373-2029
Pojawia się w:
Archives of Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Cardinality of a minimal forbidden graph family for reducible additive hereditary graph properties
Autorzy:
Drgas-Burchardt, Ewa
Powiązania:
https://bibliotekanauki.pl/articles/743169.pdf
Data publikacji:
2009
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
hereditary graph property
lattice of additive hereditary graph properties
minimal forbidden graph family
join in the lattice
reducibility
Opis:
An additive hereditary graph property is any class of simple graphs, which is closed under isomorphisms unions and taking subgraphs. Let $L^a$ denote a class of all such properties. In the paper, we consider H-reducible over $L^a$ properties with H being a fixed graph. The finiteness of the sets of all minimal forbidden graphs is analyzed for such properties.
Źródło:
Discussiones Mathematicae Graph Theory; 2009, 29, 2; 263-274
2083-5892
Pojawia się w:
Discussiones Mathematicae Graph Theory
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Technological Aspects of Execution of Welded Joints in Hollow Sections
Autorzy:
Kuchta, K.
Silezin, R.
Żwirek, P.
Powiązania:
https://bibliotekanauki.pl/articles/104810.pdf
Data publikacji:
2018
Wydawca:
Politechnika Rzeszowska im. Ignacego Łukasiewicza. Oficyna Wydawnicza
Tematy:
steel structures
lattice structures
welded joints
hollow section
Opis:
Steel structures designed according to Eurocode 3 are executed in accordance with the provisions of the standard PN-EN 1090-2, which is referred to in Eurocode 3. In addition, the standard PN-EN 1090-2 refers to in its content a number of welding standards, e.g. PN-EN ISO 9692-1. These standards provide guidelines for welded connections, which should be applied in the case of joints connecting steel hollow sections. Analysis of above-mentioned provisions revealed that for fillet welds they are simultaneously fulfilled only if the inclination angles of the elements are in the range of 70°-100°. According to recommendations of PN-EN 1993-1-8 and EN 1090-2, the same weld type around the perimeter of the element connected to the chord of lattice structure is possible to execute only for inclination angle lower than 60°. Discrepancies between these standards also exist with regard to the interpretation of the dimension of the flare groove welds in connections of rectangular hollow sections with the same width. In addition, analyses of the recommendations for welding in cold-formed zones indicate that, for steel grades currently used for the production of cold-formed rectangular hollow sections, welding in these zones is not permitted only for profiles with wall thickness equal to 12.5 and 16 mm. The above-mentioned issues point out the need for mutual unification of standards for the design and execution of steel joints in hollow sections.
Źródło:
Czasopismo Inżynierii Lądowej, Środowiska i Architektury; 2018, 65, 2; 35-42
2300-5130
2300-8903
Pojawia się w:
Czasopismo Inżynierii Lądowej, Środowiska i Architektury
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Research of microstructure of molybden doped weldings of oil and gas pipelines
Autorzy:
Pandova, Iveta
Rimar, Miroslav
Makarenko, Valery
Vinnikov, Yuri
Mangura, Andrey
Zaborowski, Tadeusz
Aloshyn, Valentyn
Powiązania:
https://bibliotekanauki.pl/articles/2037421.pdf
Data publikacji:
2021
Wydawca:
STE GROUP
Tematy:
structure
fracture
corrosion
crystal lattice
non–metallic inclusions
Opis:
Still existing scientific, technical and technological developments to improve the quality of welded joints of metal pipe structures contain contradictions and uncertainty about the effects of alloying elements, such as molybdenum, mechanical and visco-plastic properties, as well as metallographic component joints. All this indicates the need for a systematic study of these problems for the development of rational metallurgical and technological measures to significantly improve the technological and corrosion-mechanical properties of weld metal. Metallographic studies, using laboratory equipment with high identifying ability, found that the doping of weld metal with molybdenum in the amount of 0.2-0.4% causes fragmentation of ferrite-pearlite structure, including carbides Mn and Fe, and also reduces the number and size of non-metallic inclusions – sulfides, oxides and silicates. Moreover, non-metallic inclusions have a dispersed appearance, which promotes plasticization of the structure, which directly increases the viscous-plastic characteristics and resistance of the metal joints to crack formation. Based on the results of metallographic research, the optimum content in the weld metal of the alloyed element – molybdenum, which is 0.2-0.4%, is determined.
Źródło:
Management Systems in Production Engineering; 2021, 4 (29); 274-279
2299-0461
Pojawia się w:
Management Systems in Production Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modeling of thermal processes proceeding in a 1D domain of crystalline solids using the lattice Boltzmann method with an interval source function
Autorzy:
Piasecka-Belkhayat, A.
Korczak, A.
Powiązania:
https://bibliotekanauki.pl/articles/281185.pdf
Data publikacji:
2017
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
lattice Boltzmann method
directed interval arithmetics
sensitivity analysis
Opis:
The interval lattice Boltzmann method (ILBM) with an uncertainly defined internal heat source function is used to simulate heat transfer in a thin silicone film. The solution to the interval Boltzmann transport equations has been obtained taking into account the rules of directed interval arithmetics. A similar analysis has been done using the sensitivity model where the Boltzmann transport equations and boundary-initial conditions have been differentiated with respect to the no-interval heat source value. The knowledge of the sensitivity function distribution and the application of the Taylor formula allow one to find the border solutions of the problem analyzed, which (to some extent) correspond to the solution obtained under the assumption of the uncertainly defined source function. In the final part of the paper, numerical computations obtained for both methods are presented.
Źródło:
Journal of Theoretical and Applied Mechanics; 2017, 55, 1; 167-175
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Isotropic distributions in hcp crystals
Autorzy:
Kontrym-Sznajd, G.
Powiązania:
https://bibliotekanauki.pl/articles/148416.pdf
Data publikacji:
2015
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
Brillouin zone
lattice harmonics
special directions
isotropic distribution
Opis:
Some anisotropic quantities in crystalline solids can be determined from their knowledge along a limited number of sampling directions. The importance of the choice of such directions is illustrated on the example of estimating, from angular correlation of annihilation radiation data, the isotropic electron momentum density in Gd.
Źródło:
Nukleonika; 2015, 60, No. 4, part 1; 741-744
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Lattice Boltzmann simulation of natural convection flow around a horizontal cylinder located beneath an insulation plate
Autorzy:
Mehrizi, A. A.
Farhadi, M.
Afrouzi, H. H.
Shayamehr, S.
Lotfizadeh, H.
Powiązania:
https://bibliotekanauki.pl/articles/949135.pdf
Data publikacji:
2013
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
free convection
isothermal cylinder
Lattice Boltzmann method (LBM)
Opis:
In this paper, two-dimensional heat transfer solution of natural convection around an isothermal cylinder located beneath an insulation wall is studied. The effects of distance ratio of the cylinder to the wall as well as the impact of the dimensionless Rayleigh number in the flow and heat transfer are taken into account. Solving the flow equations for L/D ratio with values 0.5, 0.7, and 1.5 and the Rayleigh number ranging from 1000 to 40000 is carried out. The results are compared with the experimental data which present a good agreement. The results indicate that the effect of weakened natural convection flow in the cylinder commences when decreasing L/D ratio from the value 1.5 to 0.5 leading to a decline in heat transfer and the Nusselt number. This process occurs in all values of the Rayleigh number. For the ratio number greater than 1.5, the impact of adiabatic wall is neglected, and there is no significant influence on the natural convection flow. Increasing the angle from 0◦to180◦results in a fall in the Nusselt number which is as a consequence of growth in the distances of isothermal lines.
Źródło:
Journal of Theoretical and Applied Mechanics; 2013, 51, 3; 729-739
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical investigation of pool nucleate boiling in nanofluid with lattice Boltzmann method
Autorzy:
Rostamzadeh, A.
Jafarpur, K.
Rad, E. G.
Powiązania:
https://bibliotekanauki.pl/articles/949317.pdf
Data publikacji:
2016
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
pool boiling
nanofluid
lattice Boltzmann method
heat transfer
Opis:
Due to significant improvement of thermal performance and other properties of nanofluids, this group of liquids is in high demand. According to the literature, the effect of nanoparticles on boiling heat transfer enhancement or degradation is not the same among different investigations. In the present article, the pseudo-potential multiphase lattice Boltzmann method is used to simulate nucleate pool boiling with two different fluids: a pure liquid and a nanofluid. The current results indicate that the contact angle is the same for both the fluid and nanofluid when the vapor bubble detachment occurs. Also, bubble departure diameter is greater in the base liquid while bubble release frequency is higher in the nanofluid. In brief, the present results demonstrate that using a nanofluid instead of its base fluid will increase the boiling heat transfer coefficient.
Źródło:
Journal of Theoretical and Applied Mechanics; 2016, 54, 3; 811-825
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Two Infinite Sequences of Pre-Maximal Extensions of the Relevant Logic E
Autorzy:
Typańska-Czajka, Lidia
Powiązania:
https://bibliotekanauki.pl/articles/749872.pdf
Data publikacji:
2019
Wydawca:
Uniwersytet Łódzki. Wydawnictwo Uniwersytetu Łódzkiego
Tematy:
relevant logic
non-classical logics
lattice
universal algebra
Opis:
The only maximal extension of the logic of relevant entailment E is the classical logic CL. A logic L ⊆ [E,CL] called pre-maximal if and only if L is a coatom in the interval [E,CL]. We present two denumerable infinite sequences of premaximal extensions of the logic E. Note that for the relevant logic R there exist exactly three pre-maximal logics, i.e. coatoms in the interval [R,CL].
Źródło:
Bulletin of the Section of Logic; 2019, 48, 1
0138-0680
2449-836X
Pojawia się w:
Bulletin of the Section of Logic
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Quasiperfect domination in triangular lattices
Autorzy:
Dejter, Italo
Powiązania:
https://bibliotekanauki.pl/articles/743129.pdf
Data publikacji:
2009
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
perfect dominating set
quasiperfect dominating set
triangular lattice
Opis:
A vertex subset S of a graph G is a perfect (resp. quasiperfect) dominating set in G if each vertex v of G∖S is adjacent to only one vertex ($d_v$ ∈ {1,2} vertices) of S. Perfect and quasiperfect dominating sets in the regular tessellation graph of Schläfli symbol {3,6} and in its toroidal quotients are investigated, yielding the classification of their perfect dominating sets and most of their quasiperfect dominating sets S with induced components of the form $K_ν$, where ν ∈ {1,2,3} depends only on S.
Źródło:
Discussiones Mathematicae Graph Theory; 2009, 29, 1; 179-198
2083-5892
Pojawia się w:
Discussiones Mathematicae Graph Theory
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Bounded lattices with antitone involutions and properties of MV-algebras
Autorzy:
Chajda, Ivan
Emanovský, Peter
Powiązania:
https://bibliotekanauki.pl/articles/728914.pdf
Data publikacji:
2004
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
antitone involution
distributive lattice
implication algebra
MV-algebra
Opis:
We introduce a bounded lattice L = (L;∧,∨,0,1), where for each p ∈ L there exists an antitone involution on the interval [p,1]. We show that there exists a binary operation · on L such that L is term equivalent to an algebra A(L) = (L;·,0) (the assigned algebra to L) and we characterize A(L) by simple axioms similar to that of Abbott's implication algebra. We define new operations ⊕ and ¬ on A(L) which satisfy some of the axioms of MV-algebra. Finally we show what properties must be satisfied by L or A(L) to obtain all axioms of MV-algebra.
Źródło:
Discussiones Mathematicae - General Algebra and Applications; 2004, 24, 1; 31-42
1509-9415
Pojawia się w:
Discussiones Mathematicae - General Algebra and Applications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Filters of lattices with respect to a congruence
Autorzy:
Sambasiva Rao, M.
El-Mohsen Badawy, Abd
Powiązania:
https://bibliotekanauki.pl/articles/729197.pdf
Data publikacji:
2014
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
congruence
filter
closure operator
θ-filter
congruence lattice
Opis:
Some properties of filters on a lattice L are studied with respect to a congruence on L. The notion of a θ-filter of L is introduced and these filters are then characterized in terms of classes of θ. For distributive L, an isomorphism between the lattice of θ-filters of L and the lattice of filters of $L_{/θ}$ is obtained.
Źródło:
Discussiones Mathematicae - General Algebra and Applications; 2014, 34, 2; 213-219
1509-9415
Pojawia się w:
Discussiones Mathematicae - General Algebra and Applications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical modelling of the transient heat transport in 2D silicon thin film using the interval lattice Boltzmann method
Autorzy:
Piasecka-Belkhayat, A.
Korczak, A.
Powiązania:
https://bibliotekanauki.pl/articles/122654.pdf
Data publikacji:
2014
Wydawca:
Politechnika Częstochowska. Wydawnictwo Politechniki Częstochowskiej
Tematy:
heat transport
interval lattice Boltzmann method
transport ciepła
Opis:
In the paper the description of numerical analysis of the heat transfer process proceeding in a two-dimensional silicon thin film is presented. It is assumed that some parameters like relaxation time and boundary temperatures appearing in the mathematical model of the analyzed problem are given as intervals. The discussed problem has been solved using the interval form of the lattice Boltzmann method applying the rules of the directed interval arithmetics. In the final part of the paper, the results of numerical computations are shown.
Źródło:
Journal of Applied Mathematics and Computational Mechanics; 2014, 13, 2; 95-103
2299-9965
Pojawia się w:
Journal of Applied Mathematics and Computational Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Theory of evanescent Bessel beams with a metallic sheet
Autorzy:
Al-Awfi, S.
Powiązania:
https://bibliotekanauki.pl/articles/173463.pdf
Data publikacji:
2013
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
optical vortex
optical lattice
metallic sheet
surface modes
Opis:
We explain how a surface optical vortex can be created when a Bessel beam is totally reflected internally at the planar surface of a dielectric on which a metallic sheet has been deposited. A two-dimensional patterning on the surface, the strongly localized intensity distribution decays with distance vertical to the surface. The characteristics of this surface optical vortex depend on the incident beam parameters and the dielectric mismatch of the media.
Źródło:
Optica Applicata; 2013, 43, 3; 539-550
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Simulations of behaviour of granular bodies using a lattice-gas automaton
Autorzy:
Kozicki, J.
Tejchman, J.
Powiązania:
https://bibliotekanauki.pl/articles/241283.pdf
Data publikacji:
2005
Wydawca:
Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN
Tematy:
collisions
dissipation
granular flow
gravity
lattice-gas automaton
Opis:
A lattice-gas automaton of hydrodynamics was used to calculate the kinematics of non-cohesive granular materials during 3 different complex two-dimensional problems: granular pile, granular flow in a vertical channel and granular flow in a parallel/converging silo. In the model, collisions and dissipation of particles were taken into account. The simulation results were qualitatively compared with experimental results.
Źródło:
Archives of Hydro-Engineering and Environmental Mechanics; 2005, 52, 1; 21-37
1231-3726
Pojawia się w:
Archives of Hydro-Engineering and Environmental Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Particle agglomeration in flow modelled with molecular dynamics coupled to a thermal Lattice Boltzmann code
Autorzy:
Jiménez, J. F. C.
Powiązania:
https://bibliotekanauki.pl/articles/1955294.pdf
Data publikacji:
2013
Wydawca:
Politechnika Gdańska
Tematy:
particle agglomeration
agglomerate structure
lattice Boltzmann method
Langevin kinetics
Opis:
Particle agglomeration can arise naturally (e.g. dust, salt) or as a result of industrial activities and/or combustion processes (e.g. spray drying, particle flame synthesis). The process itself and its mechanisms are important for many applications since the physical properties of the final structures are mainly determined by the composition, number, diameter and geometric arrangement of their constituent primary particles. Thus, knowing and controlling the extent of agglomeration meets a growing interest in environmental and industrial concerns. The objective of the paper is to develop a simulation model of particles suspended in a flowing fluid using MD simulations coupled to a Lattice Boltzmann (LB) solver. These simulations allowed determining the agglomerate transport and deposition rates depending on the flow conditions and agglomerate structure and understanding the relationship between agglomerate characteristics (i.e. growth kinetics and morphology) and their behavior in a flow field. Two systems of 2000 and 1000 particles were simulated at 300 K and 600 K both of them in a known fluid. Simulations using a Langevin thermostat were also performed to compare with the LB thermostat. This allowed quantifying the influence of the fluid flow on the agglomeration process and agglomerate properties. In further applications, this will help to a priori tailor the flow conditions to achieve a desired aggregate morphology. As a result, reasonable aggregate morphologies were achieved. One of the main conclusions is that taking into account the fluid flow (LB solver) the agglomeration process of the particles is notably accelerated in comparison to the Langevin simulations. One of the main implications of this work could be the possibility of using a known fluid to accelerate an aglomeration process given a suitable fluid and to find a desirable configuration of agglomerates. Another conclusion is that the agglomeration process is sensitive to the temperature variation and that the number of particles in the system influences the final configuration of agglomerates in LB simulations.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2013, 17, 3-4; 181--213
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Execution and Inspection of Steel Hollow Sections Welded Joint
Autorzy:
Kuchta, K.
Silezin, R.
Żwirek, P.
Powiązania:
https://bibliotekanauki.pl/articles/104583.pdf
Data publikacji:
2018
Wydawca:
Politechnika Rzeszowska im. Ignacego Łukasiewicza. Oficyna Wydawnicza
Tematy:
steel structures
lattice structures
hollow section
welded joints
welds
Opis:
The hollow section welded joints require a number of actions before starting welding and appropriate supervision during this operation to achieve joints with adequate quality level, which should be confirmed by the post-completion tests. The execution of hollow section joints is associated not only with welding, but also with cutting and additional machining of edges. In some cases, weld surfacing is also applied to correct sections fit-up. Weld surfacing and thermal cutting can cause local hardening of connected elements. The welding has to be preceded by an assessment of the previous technological processes. The welded joints can be only executed on the basis of detailed Welding Procedure Specifications (WPS). It is advisable to manufacture - in accordance with previously prepared WPS - pre-production joints for testing, proving the ability of the welding personnel to execute welded joints with specified quality, using the available equipment. The quality of welded joints is proved by testing. A type of conducted tests, thus scope and type of welding defects possible to detect, depends on the weld type, wall thickness of connected elements and joint geometry. The authors’ experience indicates that the proper execution of the welded joint of hollow sections is difficult task, which often requires pre-production quality testing of the joints.
Źródło:
Czasopismo Inżynierii Lądowej, Środowiska i Architektury; 2018, 65, 2; 69-80
2300-5130
2300-8903
Pojawia się w:
Czasopismo Inżynierii Lądowej, Środowiska i Architektury
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Old materials – new capabilities: lattice materials in structural mechanics
Autorzy:
Augustyniak, M.
Powiązania:
https://bibliotekanauki.pl/articles/281102.pdf
Data publikacji:
2018
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
lattice materials
additive layer manufacturing
specific stiffness
topological optimisation
Opis:
Lattice materials (LM) are a novel concept stemming from the combination of crystallography and structural optimisation algorithms. Their practical applications have become real with the advent of versatile additive layer manufacturing (ALM) techniques and the development of dedicated CAD/CAE tools. This work critically reviews one of the major claims concerning LMs, namely their excellent stiffness-to-weight performance. First, a brief literature review of spatially uniform LMs is presented, focusing on specific strength of standard engineering materials as compared with novel structures. An original modelling and optimisation is carried out on a flat panel subject to combined shear and bending load. The calculated generalised specific stiffness is compared against reference values obtained for a uniform panel and the panel subjected to topological optimisation. The monomaterial, a spatially repetitive solution turns out to be poorly suited for stiff, lightweight designs, because of suboptimal material distribution. Spatially non-uniform and locally size-optimised structures perform better. However, its advantage over manufacturable, topologically-optimised conventional designs can at best be marginal (< 10%). Cubic-cell lattices cannot replace conventional bulk materials in the typical engineering use. The multi-cell-type and multi-material lattice structures, albeit beyond the scope of this article, are more promising from the point of view of mechanical properties. The possibility of approaching the linear scaling reported in the recent litterature can make them an attractive option in ultra-low weight designs.
Źródło:
Journal of Theoretical and Applied Mechanics; 2018, 56, 1; 213-226
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On continuum modelling of the dynamic behaviour of periodic lattice-type plates with a complex structure
Autorzy:
Cielecka, I.
Jędrysiak, J.
Powiązania:
https://bibliotekanauki.pl/articles/282045.pdf
Data publikacji:
2002
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
periodic lattice-type plate
length-scale effect
tolerance averaging
Opis:
A new continuum model for studying the dynamic problems of periodic elastic lattice-type plates of an arbitrary lay-out is proposed. The general line of approach is partly based on the tolerance averaging techniques developed by Woźniak and Wierzbicki (2000) for the termomechanics of composite solids and applied by Cielecka et al. (1998, 2000) to the modelling of dense cellular structures. The proposed model describes the microstructure length-scale effect on the dynamic plate behaviour. The obtained equations are applied to the analysis of wave propagation in a special latticed plate. It is shown that the lenght-scale effect plays an important role and cannot be neglected in the above analysis.
Ciągły model zagadnień dynamicznych periodycznych płyt siatkowych o złożonej strukturze. W pracy zaproponowano nowy ciągły model do analizowania zagadnień dynamicznych sprężystych, periodycznych płyt siatkowych. W przedstawionym podejściu częściowo wykorzystano technikę tolerancyjnego uśredniania, opracowaną przez Woźniaka i Wierzbickiego (2000) dla termomechaniki kompozytów. Podejście to zastosowano w pracach Cieleckiej i in. (1998, 2000) w modelowaniu gęstych struktur komórkowych. Zaproponowany model opisuje wpływ wielkości mikrostruktury na dynamikę płyty siatkowej. Otrzymane równania zastosowano do analizy propagacji fal w pewnym szczególnym przypadku płyty. Pokazano, że efekt skali odgrywa ważną rolę i nie może być pominięty w powyższej analizie.
Źródło:
Journal of Theoretical and Applied Mechanics; 2002, 40, 1; 23-46
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Probability measures and logical connectives on quantum logics
Autorzy:
Nánásiová, Oľga
Valášková, Ľubica
Čerňanová, Viera
Powiązania:
https://bibliotekanauki.pl/articles/384839.pdf
Data publikacji:
2019
Wydawca:
Sieć Badawcza Łukasiewicz - Przemysłowy Instytut Automatyki i Pomiarów
Tematy:
logical connectives
orthomodular lattice
quantum logic
probability measure
state
Opis:
The present paper is devoted to modelling of a probabi‐ lity measure of logical connectives on a quantum logic via a G‐map, which is a special map on it. We follow the work in which the probability of logical conjunction (AND), dis‐ junction (OR), symmetric difference (XOR) and their nega‐ tions for non‐compatible propositions are studied. Now we study all remaining cases of G‐maps on quantum lo‐ gic, namely a probability measure of projections, of impli‐ cations, and of their negations. We show that unlike clas‐ sical (Boolean) logic, probability measures of projections on a quantum logic are not necessarilly pure projections. We indicate how it is possible to define a probability me‐ asure of implication using a G‐map in the quantum logic, and then we study some properties of this measure which are different from a measure of implication in a Boolean algebra. Finally, we compare the properties of a G‐map with the properties of a probability measure related to logical connectives on a Boolean algebra.
Źródło:
Journal of Automation Mobile Robotics and Intelligent Systems; 2019, 13, 3; 64-73
1897-8649
2080-2145
Pojawia się w:
Journal of Automation Mobile Robotics and Intelligent Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Uniform approximation by polynomials with integer coefficients
Autorzy:
Lipnicki, A.
Powiązania:
https://bibliotekanauki.pl/articles/254816.pdf
Data publikacji:
2016
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
approximation by polynomials with integer coefficients
lattice
covering radius
Opis:
Let r, n be positive integers with n ≥ 6r. Let P be a polynomial of degree at most n on [0,1] with real coefficients, such that [formula] are integers for k = 0,…, r — 1. It is proved that there is a polynomial Q of degree at most n with integer coefficients such that [formula] for x ∈ [0,1], where C1, C2 are some numerical constants. The result is the best possible up to the constants.
Źródło:
Opuscula Mathematica; 2016, 36, 4; 489-498
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On the special context of independent sets
Autorzy:
Slezák, Vladimír
Powiązania:
https://bibliotekanauki.pl/articles/728756.pdf
Data publikacji:
2001
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
context
complete lattice
join-independent and meet-independent sets
Opis:
In this paper the context of independent sets $J^{p}_{L}$ is assigned to the complete lattice (P(M),⊆) of all subsets of a non-empty set M. Some properties of this context, especially the irreducibility and the span, are investigated.
Źródło:
Discussiones Mathematicae - General Algebra and Applications; 2001, 21, 1; 115-122
1509-9415
Pojawia się w:
Discussiones Mathematicae - General Algebra and Applications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Flocks in universal and Boolean algebras
Autorzy:
Ricci, Gabriele
Powiązania:
https://bibliotekanauki.pl/articles/729039.pdf
Data publikacji:
2010
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
combinators
elementary functions
closure system
interpolators
semi-affine lattice
Opis:
We propose the notion of flocks, which formerly were introduced only in based algebras, for any universal algebra. This generalization keeps the main properties we know from vector spaces, e.g. a closure system that extends the subalgebra one. It comes from the idempotent elementary functions, we call "interpolators", that in case of vector spaces merely are linear functions with normalized coefficients.
The main example, we consider outside vector spaces, concerns Boolean algebras, where flocks form "local" algebras with a sparseness similar to the one of vector spaces. We also outline the problem of generalizing the Segre transformations of based algebras, which used certain flocks, in order to approach a general transformation notion.
Źródło:
Discussiones Mathematicae - General Algebra and Applications; 2010, 30, 1; 45-69
1509-9415
Pojawia się w:
Discussiones Mathematicae - General Algebra and Applications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Model of the two well potential for Hg-atoms in the Hg1-xCdxTe alloy lattice
Autorzy:
Polit, J.
Powiązania:
https://bibliotekanauki.pl/articles/200135.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
well potential
Hg-atoms
Hg1-xCdxTe alloy lattice
Opis:
The problem of the additional phonon modes (APM) of the far infrared spectra in the range of 100–115 cm-1 for the Hg1-xCdxTe alloys has been discussed for the last forty years. The model of two well potential of the mercury atoms in the Hg1-xCdxTe lattice is proposed for interpretation of these APM. Analysis was performed for samples of different compositions (0.06 < x < 0.7) and different types (nand p-type) of conductivity.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2011, 59, 3; 331-341
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Determination of Fe2+/Fe3+ mole ratio based on the change of precursor lattice parameters of wustite based iron catalysts for the ammonia synthesis
Autorzy:
Jurkowski, Artur
Lendzion-Bieluń, Zofia
Powiązania:
https://bibliotekanauki.pl/articles/778447.pdf
Data publikacji:
2019
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
wustite ammonia catalyst
XRD technique
manganometry
wustite lattice parameter
Opis:
In the presented article, oxide forms of iron catalysts with the wustite structure and with a R = Fe2+/Fe3+ molar ratio in the range from 3.78 to 8.16 were investigated. The chemical composition of the tested catalyst precursors was determined by inductively coupled plasma optical emission spectrometry (ICP-OES). The X-ray diffraction (XRD) technique was used to determine the phase composition and location of reflections characteristic of the Fe1−xO phase. The molar ratio of iron ions R = Fe2+/Fe3+ was determined by manganometric titration. The distribution of promoters in the structure of iron catalyst precursors with different R = Fe2+/Fe3+  ratio was determined by a selective etching method. The dependence of the lattice parameter ao value in the crystal structure Fe1−xO on the molar ratio R = Fe2+/Fe3+ was determined. On the basis of the determined dependence, R can easily be calculated in catalyst precursors of the wustite structure.
Źródło:
Polish Journal of Chemical Technology; 2019, 21, 3; 48-52
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of radial fins on natural convection between horizontal circular and square cylinders
Autorzy:
Jafari, I.
Mahdavy-Moghadam, H.
Taeibi-Rahni, M.
Dayyan, M.
Seyyedi, S. M.
Powiązania:
https://bibliotekanauki.pl/articles/279844.pdf
Data publikacji:
2014
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
radial fins
natural convection
lattice Boltzmann method
horizontal annulus
Opis:
In this paper, the effects of the number and arrangement of radial fins on laminar natural co- nvection between horizontal circular and square cylinders has been investigated numerically with the lattice Boltzmann method. The Rayleigh number is varied from Ra = 10³ − 10⁶), the number of fins (N = 2 − 8) and the Prandtl number (Pr = 0.7). The local Nusselt number profiles over the outer and inner cylinders and the average Nusselt number over the top, bottom and side walls of the outer cold square cylinder are obtained. The temperature and streamline contours are also depicted to investigate the heat and fluid flow behavior inside the computational domain.
Źródło:
Journal of Theoretical and Applied Mechanics; 2014, 52, 3; 827-837
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Neurocomputing Techniques to Predict the 2D Structures by Using Lattice Dynamics of Surfaces
Autorzy:
Belayadi, A.
Bourahla, B.
Mekideche-Chafa, F.
Powiązania:
https://bibliotekanauki.pl/articles/1032604.pdf
Data publikacji:
2017-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
neurocomputing
surface and Wood notation
vibration and lattice dynamics
Opis:
A theoretical study of artificial neural network modelling, based on vibrational dynamic data for 2D lattice, is proposed in this paper. The main purpose is to establish a neurocomputing model able to predict the 2D structures of crystal surfaces. In material surfaces, atoms can be arranged in different possibilities, defining several 2D configurations, such as triangular, square lattices, etc. To describe these structures, we usually employ the Wood notations, which are considered as the simplest manner and the most frequently used to spot the surfaces in physics. Our contribution consists to use the vibration lattice of perfect 2D structures along with the matrix and Wood notations to build up an input-output set to feed the neural model. The input data are given by the frequency modes over high symmetry points and the group velocity. The output data are given by the basis vectors corresponding to surface reconstruction and the rotation angle which aligns the unit cell of the reconstructed surface. Results showed that the method of collecting the dataset was very suitable for building a neurocomputing model that is able to predict and classify the 2D surface of the crystals. Moreover, the model was able to generate the lattice spacing for a given structure.
Źródło:
Acta Physica Polonica A; 2017, 132, 4; 1314-1319
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Prime ideals in the lattice of additive induced-hereditary graph properties
Autorzy:
Berger, Amelie
Mihók, Peter
Powiązania:
https://bibliotekanauki.pl/articles/743387.pdf
Data publikacji:
2003
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
hereditary graph property
prime ideal
distributive lattice
induced subgraphs
Opis:
An additive induced-hereditary property of graphs is any class of finite simple graphs which is closed under isomorphisms, disjoint unions and induced subgraphs. The set of all additive induced-hereditary properties of graphs, partially ordered by set inclusion, forms a completely distributive lattice. We introduce the notion of the join-decomposability number of a property and then we prove that the prime ideals of the lattice of all additive induced-hereditary properties are divided into two groups, determined either by a set of excluded join-irreducible properties or determined by a set of excluded properties with infinite join-decomposability number. We provide non-trivial examples of each type.
Źródło:
Discussiones Mathematicae Graph Theory; 2003, 23, 1; 117-127
2083-5892
Pojawia się w:
Discussiones Mathematicae Graph Theory
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Copies of \(\mathbb R^{\mathbb N}\) in F-lattices
Autorzy:
Wnuk, Witold
Powiązania:
https://bibliotekanauki.pl/articles/744986.pdf
Data publikacji:
2016
Wydawca:
Polskie Towarzystwo Matematyczne
Tematy:
metrizable locally solid Riesz space
F-lattice
sequence spaces
Opis:
Modifying ideas presented in [14] we prove that a complete metrizable locally solid Riesz space \(E\) contains a linear subspace linearly homeomorphic to \(\mathbb R^{\mathbb N}\) iff \(E\) contains a sublattice order isomorphic to \(\mathbb R^{\mathbb N}\).
Źródło:
Commentationes Mathematicae; 2016, 56, 2
0373-8299
Pojawia się w:
Commentationes Mathematicae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Theoretical Predictions of Lattice Parameters and Mechanical Properties of Pentaerythritol Tetranitrate under the Temperature and Pressure by Molecular Dynamics Simulations
Autorzy:
Tan, J.J.
Hu, C.
Li, Y.
Ge, N.
Chen, T.
Ji, G.
Powiązania:
https://bibliotekanauki.pl/articles/1033453.pdf
Data publikacji:
2017-02
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
molecular dynamics
lattice parameter
equation of state
elasticity
mechanical properties
Opis:
Molecular dynamics simulations with condensed-phase optimized molecular potentials for atomistic simulation studies force field are performed to investigate the structure, equation of state, and mechanical properties of high energetic material pentaerythritol tetranitrate. The equilibrium structural parameters, pressure-volume relationship and elastic constants at ambient conditions agree excellently with experiments. In addition, fitting the pressure-volume data to the Birch-Murnaghan or Murnaghan equation of state, the bulk modulus B₀ and its first pressure derivative B'₀ are obtained. Moreover, the elastic constants are calculated in the pressure range of 0-10 GPa at room temperature and in the temperature range of 200-400 K at the standard pressure, respectively. By the Voigt-Reuss-Hill approximation, the mechanical properties such as bulk modulus B, shear modulus G, and the Young modulus E are also obtained successfully. The predicted physical properties under temperature and pressure can provide powerful guidelines for the engineering application and further experimental investigations.
Źródło:
Acta Physica Polonica A; 2017, 131, 2; 318-323
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The structure of atoms (hereditarily indecomposable continua)
Autorzy:
Ball, R.
Hagler, J.
Sternfeld, Yaki
Powiązania:
https://bibliotekanauki.pl/articles/1205357.pdf
Data publikacji:
1998
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
atoms (hereditarily indecomposable continua)
ultrametric spaces
isometries
lattices
lattice isomorphism
Opis:
Let X be an atom (= hereditarily indecomposable continuum). Define a metric ϱ on X by letting $ϱ(x,y) = W(A_{xy})$ where $A_{x,y}$ is the (unique) minimal subcontinuum of X which contains x and y and W is a Whitney map on the set of subcontinua of X with W(X) = 1. We prove that ϱ is an ultrametric and the topology of (X,ϱ) is stronger than the original topology of X. The ϱ-closed balls C(x,r) = {y ∈ X:ϱ ( x,y) ≤ r} coincide with the subcontinua of X. (C(x,r) is the unique subcontinuum of X which contains x and has Whitney value r.) It is proved that for any two (nontrivial) atoms and any Whitney maps on them, the corresponding ultrametric spaces are isometric. This implies in particular that the combinatorial structure of subcontinua is identical in all atoms. The set M(X) of all monotone upper semicontinuous decompositions of X is a lattice when ordered by refinement. It is proved that for two atoms X and Y, M(X) is lattice isomorphic to M(Y) if and only if X is homeomorphic to Y.
Źródło:
Fundamenta Mathematicae; 1998, 156, 3; 261-278
0016-2736
Pojawia się w:
Fundamenta Mathematicae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Finite atomistic lattices that can be represented as lattices of quasivarieties
Autorzy:
Adaricheva, K.
Dziobiak, Wiesław
Gorbunov, V.
Powiązania:
https://bibliotekanauki.pl/articles/1208668.pdf
Data publikacji:
1993
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
atomistic lattice
quasivariety
Mal'cev problem
equa-closure operator
semilattice
Opis:
We prove that a finite atomistic lattice can be represented as a lattice of quasivarieties if and only if it is isomorphic to the lattice of all subsemilattices of a finite semilattice. This settles a conjecture that appeared in the context of [11].
Źródło:
Fundamenta Mathematicae; 1993, 142, 1; 19-43
0016-2736
Pojawia się w:
Fundamenta Mathematicae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Some counting formulas for finite distributive lattices
Autorzy:
Grygiel, J.
Powiązania:
https://bibliotekanauki.pl/articles/122017.pdf
Data publikacji:
2010
Wydawca:
Uniwersytet Humanistyczno-Przyrodniczy im. Jana Długosza w Częstochowie. Wydawnictwo Uczelniane
Tematy:
finite distributive lattice
combinatorial theory
skończona krata dystrybutywna
teoria kombinatoryczna
Opis:
In the paper we show that the weighted double skeleton of a finite distributive lattice is a suffcient structure to characterize the lattice numerically. We prove some combinatorial formulas for the number of all elements of a finite distributive lattice with the given weighted double skeleton, all its elements with exactly k lower covers and all its covering pairs. Introducing some simple examples, we show how the formulas work.
Źródło:
Scientific Issues of Jan Długosz University in Częstochowa. Mathematics; 2010, 15; 43-48
2450-9302
Pojawia się w:
Scientific Issues of Jan Długosz University in Częstochowa. Mathematics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Preserving Filtering Unification by Adding Compatible Operations to Some Heyting Algebras
Autorzy:
Dzik, Wojciech
Radeleczki, Sándor
Powiązania:
https://bibliotekanauki.pl/articles/749994.pdf
Data publikacji:
2016
Wydawca:
Uniwersytet Łódzki. Wydawnictwo Uniwersytetu Łódzkiego
Tematy:
filtering unification
compatible operation
intuitionistic logic
Heyting algebra
residuated lattice
Opis:
We show that adding compatible operations to Heyting algebras and to commutative residuated lattices, both satisfying the Stone law ¬x ⋁ ¬¬x = 1, preserves filtering (or directed) unification, that is, the property that for every two unifiers there is a unifier more general then both of them. Contrary to that, often adding new operations to algebras results in changing the unification type. To prove the results we apply the theorems of [9] on direct products of l-algebras and filtering unification. We consider examples of frontal Heyting algebras, in particular Heyting algebras with the successor, γ and G operations as well as expansions of some commutative integral residuated lattices with successor operations.
Źródło:
Bulletin of the Section of Logic; 2016, 45, 3/4
0138-0680
2449-836X
Pojawia się w:
Bulletin of the Section of Logic
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Lexico extension and a cut completion of a half l-group
Autorzy:
Černák, Štefan
Demko, Milan
Powiązania:
https://bibliotekanauki.pl/articles/728997.pdf
Data publikacji:
2002
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
half lattice ordered group
l-group
cut completion
lexico extension
Opis:
The cut completi on of an hl-group G with the abelian increasing part is investigated under the assumption that G is a lexico extension of its hl-subgroup.
Źródło:
Discussiones Mathematicae - General Algebra and Applications; 2002, 22, 2; 141-152
1509-9415
Pojawia się w:
Discussiones Mathematicae - General Algebra and Applications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Linear model genealogical tree application to an odontology experiment
Autorzy:
Covas, Ricardo
Powiązania:
https://bibliotekanauki.pl/articles/729994.pdf
Data publikacji:
2007
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
commutative Jordan algebra
binary operations
Kronecker matrix product
lattice
projectors
Opis:
Commutative Jordan algebras play a central part in orthogonal models. We apply the concepts of genealogical tree of an Jordan algebra associated to a linear mixed model in an experiment conducted to study optimal choosing of dentist materials. Apart from the conclusions of the experiment itself, we show how to proceed in order to take advantage of the great possibilities that Jordan algebras and mixed linear models give to practitioners.
Źródło:
Discussiones Mathematicae Probability and Statistics; 2007, 27, 1-2; 47-77
1509-9423
Pojawia się w:
Discussiones Mathematicae Probability and Statistics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Improving energy compaction of a wavelet transform using genetic algorithm and fast neural network
Autorzy:
Stolarek, J.
Powiązania:
https://bibliotekanauki.pl/articles/964025.pdf
Data publikacji:
2010
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
wavelet transform
neural networks
genetic algorithms
signal processing
lattice structure
Opis:
In this paper a new method for adaptive synthesis of a smooth orthogonal wavelet, using fast neural network and genetic algorithm, is introduced. Orthogonal lattice structure is presented. A new method of supervised training of fast neural network is introduced to synthesize a wavelet with desired energy distribution between output signals from low–pass and high–pass filters on subsequent levels of a Discrete Wavelet Transform. Genetic algorithm is proposed as a global optimization method for defined objective function, while neural network is used as a local optimization method to further improve the result. Proposed approach is tested by synthesizing wavelets with expected energy distribution between low– and high–pass filters. Energy compaction of proposed method and Daubechies wavelets is compared. Tests are performed using image signals.
Źródło:
Archives of Control Sciences; 2010, 20, 4; 417-433
1230-2384
Pojawia się w:
Archives of Control Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Compressor Blade Fatigue Diagnostics and Modelling with the Use of Modal Analysis
Autorzy:
Witoś, M.
Stefaniuk, M.
Powiązania:
https://bibliotekanauki.pl/articles/97913.pdf
Data publikacji:
2011
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Lotnictwa
Tematy:
compressor blade
damage
fatigue
modal analysis
lattice-spin coupling
FEM
Opis:
This paper investigates the diagnostic and research aspects of the compressor blade fatigue. The authors have reviewed the characteristics of different modes of metal blade fatigue (LCF, HCF, VHCF). The polycrystalline defects and impurities influencing the fatigue, along with their related surface finish techniques, have been taken into account. The experimental methods of structural health assessment have been considered. The Tip Timing (TTM), Experimental Modal Analysis (EMA) and Metal Magnetic Memory (MMM) provide information on the damage of the diagnosed object (compressor blade). It has been proven that the shape of resonance characteristics gives an ability to determinate if fatigue or a blade crack is concerned. Early damage symptoms, i.e. modal properties of material strengthening and weakening phases have been described. The experimental verification of the FEM model is presented based on a large body of experimental data collected by the author.
Źródło:
Fatigue of Aircraft Structures; 2011, 3; 112-133
2081-7738
2300-7591
Pojawia się w:
Fatigue of Aircraft Structures
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On the yield surface of a typical bending-dominant periodic lattice metamaterial
Autorzy:
Wang, Yongjun
Liu, Jinxing
Powiązania:
https://bibliotekanauki.pl/articles/2200879.pdf
Data publikacji:
2023
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
bending-dominant periodic lattice
BDPL
yield
metamaterial
strain energy equivalence
Opis:
A theoretical method for analyzing the initial yield of a typical bending-dominant peri- odic lattice (BDPL) is established. Based on the principle of strain energy equivalence, the macroscopic effective stiffnesses of lattices are calculated. An empirical formula is employed to consider the contributions of both the axial force and bending moment. The initial yield surface of BDPL can be figured out by comparing the effective stress of each strut to the yield strength of the matrix material. The method is applicable to various BDPLs, which we believe is a helpful extension to the method for lattices comprising axial-tension bars in the literature.
Źródło:
Journal of Theoretical and Applied Mechanics; 2023, 61, 1; 175--187
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Some properties of congurence relations on orthomodular lattices
Autorzy:
Dorfer, Gerhard
Powiązania:
https://bibliotekanauki.pl/articles/728766.pdf
Data publikacji:
2001
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
orthomodular lattice
congruence relation
congruence-regular
congruence-uniform
congruence-permutable
Opis:
In this paper congruences on orthomodular lattices are studied with particular regard to analogies in Boolean algebras. For this reason the lattice of p-ideals (corresponding to the congruence lattice) and the interplay between congruence classes is investigated. From the results adduced there, congruence regularity, uniformity and permutability for orthomodular lattices can be derived easily.
Źródło:
Discussiones Mathematicae - General Algebra and Applications; 2001, 21, 1; 57-66
1509-9415
Pojawia się w:
Discussiones Mathematicae - General Algebra and Applications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The completely distributive lattice of machine invariant sets of infinite words
Autorzy:
Belovs, Aleksandrs
Buls, Jānis
Powiązania:
https://bibliotekanauki.pl/articles/728892.pdf
Data publikacji:
2007
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
mealy machine
machine invariant class
completely distributive lattice
length
width
Opis:
We investigate the lattice of machine invariant classes. This is an infinite completely distributive lattice but it is not a Boolean lattice. The length and width of it is c. We show the subword complexity and the growth function create machine invariant classes.
Źródło:
Discussiones Mathematicae - General Algebra and Applications; 2007, 27, 1; 109-121
1509-9415
Pojawia się w:
Discussiones Mathematicae - General Algebra and Applications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The lattice of subvarieties of the biregularization of the variety of Boolean algebras
Autorzy:
Płonka, Jerzy
Powiązania:
https://bibliotekanauki.pl/articles/729041.pdf
Data publikacji:
2001
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
subdirectly irreducible algebra
lattice of subvarieties
Boolean algebra
biregular identity
Opis:
Let τ: F → N be a type of algebras, where F is a set of fundamental operation symbols and N is the set of all positive integers. An identity φ ≈ ψ is called biregular if it has the same variables in each of it sides and it has the same fundamental operation symbols in each of it sides. For a variety V of type τ we denote by $V_{b}$ the biregularization of V, i.e. the variety of type τ defined by all biregular identities from Id(V).
Let B be the variety of Boolean algebras of type $τ_{b}: {+,·,´} → N$, where $τ_{b}(+) = τ_{b}(·) = 2$ and $τ_{b}(´) = 1$. In this paper we characterize the lattice $ℒ(B_{b})$ of all subvarieties of the biregularization of the variety B.
Źródło:
Discussiones Mathematicae - General Algebra and Applications; 2001, 21, 2; 255-268
1509-9415
Pojawia się w:
Discussiones Mathematicae - General Algebra and Applications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of the generally available WIMS versions to modern PWRs
Autorzy:
Kulikowska, T.
Stadnik, A.
Andrzejewski, K.
Boettcher, A.
Powiązania:
https://bibliotekanauki.pl/articles/147884.pdf
Data publikacji:
2012
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
reactor calculations
lattice spectrum code
resonance integrals
gadolinium bearing fuel
Opis:
The generally available versions of WIMS (Winfrith improved multigroup scheme) code have been used at the Institute of Atomic Energy POLATOM (IEA POLATOM, Otwock/Świerk, Poland) for a variety of reactor lattice analyses since 1974. With planned construction of new generation PWRs (power water reactors) in Poland, a question of WIMSD-5B version applicability to lattice calculations of strongly heterogeneous assemblies with gadolinium poisoned pins became actual. The present paper deals with modeling of the fuel assemblies using the version of WIMSD-5B extended at the IEA POLATOM. It was shown that with a careful choice of computational options the code properly describes main physical parameters of modern PWR fuel assemblies.
Źródło:
Nukleonika; 2012, 57, 1; 87-93
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Disturbing effect of different dental materials on the MRI results : preliminary study
Autorzy:
Burchardt, D. V.
Borysewicz-Lewicka, M.
Powiązania:
https://bibliotekanauki.pl/articles/306511.pdf
Data publikacji:
2013
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
dental materials
MRI
spin-lattice
relaxation time T
materiały stomatologiczne
Opis:
The influence of different dental materials used for conserving reconstruction of teeth on the magnetic resonance imaging assessed on the basis of changes in NMR proton relaxation T1 of the physiological environment represented by the physiological salt solution has been studied. The dental materials studied varied in a wide range of chemical compositions: composites (Silux Plus made by 3M Dental, Tetric Cream made by Ivoclar-Vivadent), pH controlling composite (Ariston pHc made by Vivadent), hybrid glass ionomer (Vitremer made by 3M Dental), compomer (Hytac made by ESPE), amalgamate without the gamma phase (Septalloy made by Septodont), chemocured phosphate cement (Agatos made by Chema-Elektromet), phosphate cement with addition of silver (Argil made by Spora-Dental). The reference standard was a 0.9% physiological solution of NaCl. The relative deviations of the spin-lattice relaxation time vary from –18.5% to +24.0%. From the point of view of magnetic resonance imaging, the materials significantly disturbing the tomographic images are the amalgamate Septalloy-Septodont and glass ionomer Vitremer-3M Dental, while the composite Tetric Cream-Vivadent has insignificant effect.
Źródło:
Acta of Bioengineering and Biomechanics; 2013, 15, 4; 49-55
1509-409X
2450-6303
Pojawia się w:
Acta of Bioengineering and Biomechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Cover of Cylinder Lattice Plastic Convert into Fuel
Autorzy:
Sarker, M.
Rashid, M. M.
Powiązania:
https://bibliotekanauki.pl/articles/412122.pdf
Data publikacji:
2013
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
plastic lattice
conversion
fuel
hydrocarbon
waste plastics material
GC-MS
Opis:
Waste plastic of cylinder lattice to liquid fuel production process was performing two step processes. 1st step process was perform muffle furnace with ceramic crucible and 2nd step process was perform glass reactor with condensation unit. Thermal degradation process was performing with furnace and temperature was 410 ?C and reactor temperature was 420 ?C. Muffle furnace was use for solid hard shape of plastic melting purpose and glass reactor was use for liquid slurry to produce vapor purpose. Liquid slurry to produce vapor was condensed and collected liquid fuel and fuel density is 0.75 g/ml. Liquid fuel production conversation rate was 71.05 %. Fuel was analysis by GC/MS and carbon chains obtain C3 to C23 from GC/MS chromatogram. Fuel color is light yellow and fuel is ignited.
Źródło:
International Letters of Chemistry, Physics and Astronomy; 2013, 6; 17-30
2299-3843
Pojawia się w:
International Letters of Chemistry, Physics and Astronomy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of vortex flow model in propeller-stator system design and analysis
Autorzy:
Król, P.
Bugalski, T.
Powiązania:
https://bibliotekanauki.pl/articles/259710.pdf
Data publikacji:
2018
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
propeller
wake improving device
upstream stator
cavitation
vortex lattice method
Opis:
The paper covers basics of the vortex model used for propeller-stator systems. The outline of the design algorithm is given and the results of its application are shown. The designed propeller-stator system was the subject of model tests run at the CTO model basin and cavitation tunnel. Stator’s influence on the delivered power required by the propeller and its revolution rate has been examined by conducting self-propulsion tests with and without stator. The tests performed in the cavitation tunnel revealed only weak tip vortex cavitation on the propeller. No cavitation was observed on the stator at the design point. A wide range of the performed tests allowed the authors to identify details of the developed theory which will require further improvement.
Źródło:
Polish Maritime Research; 2018, 1; 35-43
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Model of a ducted axial-flow hydrokinetic turbine – results of experimental and numerical examination
Autorzy:
Góralczyk, A.
Adamkowski, A.
Powiązania:
https://bibliotekanauki.pl/articles/260336.pdf
Data publikacji:
2018
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
Vortex Lattice Methods
ducted hydrokinetic turbines
cavitation tunnel
performance characteristics
Opis:
The article presents the numerical algorithm of the developed computer code which calculates performance characteristics of ducted axial-flow hydrokinetic turbines. The code makes use of the vortex lattice method (VLM), which has been developed and used in IMP PAN for years, to analyse the operation of various fluid-flow machines. To verify the developed software, a series of model tests have been performed in the cavitation tunnel being part of IMP PAN research equipment.
Źródło:
Polish Maritime Research; 2018, 3; 113-122
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Copies of the sequence space \(\omega\) in \(F\)-lattices with applications to Musielak−Orlicz spaces
Autorzy:
Wójtowicz, Marek
Wiśniewska, Halina
Powiązania:
https://bibliotekanauki.pl/articles/1912860.pdf
Data publikacji:
2016
Wydawca:
Polskie Towarzystwo Matematyczne
Tematy:
F-space
F-lattice
Musielak-Orlicz space
sequence space \(\omega\)
Opis:
Let \(E\) be a fixed real function \(F\)-space, i.e., \(E\) is an order ideal in \(L_0(S,\Sigma,\mu)\) endowed with a monotone \(F\)-norm \(\|\|\) under which \(E\) is topologically complete. We prove that \(E\) contains an isomorphic (topological) copy of \(\omega\), the space of all sequences, if and only if \(E\) contains a lattice-topological copy \(W\) of \(\omega\). If \(E\) is additionally discrete, we obtain a much stronger result: \(W\) can be a projection band; in particular, \(E\) contains a~complemented copy of \(\omega\). This solves partially the open problem set recently by W. Wnuk. The property of containing a copy of \(\omega\) by a Musielak−Orlicz space is characterized as follows. (1) A sequence space \(\ell_{\Phi}\), where \(\Phi = (\varphi_n)\), contains a copy of \(\omega\) iff \(\inf_{n \in \mathbb{N}} \varphi_n (\infty) = 0\), where \(\varphi_n (\infty) = \lim_{t \to \infty} \varphi_n (t)\). (2) If the measure \(\mu\) is atomless, then \(\omega\) embeds isomorphically into \(L_{\mathcal{M}} (\mu)\) iff the function \(\mathcal{M}_{\infty}\) is positive and bounded on some set \(A\in \Sigma\) of positive and finite measure, where \(\mathcal{M}_{\infty} (s) = \lim_{n \to \infty} \mathcal{M} (n, s)\), \(s\in S\). In particular, (1)' \(\ell_\varphi\) does not contain any copy of \(\omega\), and (2)' \(L_{\varphi} (\mu)\), with \(\mu\) atomless, contains a~copy \(W\) of \(\omega\) iff \(\varphi\) is bounded, and every such copy \(W\) is uncomplemented in \(L_{\varphi} (\mu)\).
Źródło:
Commentationes Mathematicae; 2016, 56, 1
0373-8299
Pojawia się w:
Commentationes Mathematicae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mechanical unfolding of DDFLN4 studied by coarse-grained knowledge-based CABS model
Autorzy:
Kouza, M.
Jamroz, M.
Gront, D.
Kmiecik, S.
Koliński, A.
Powiązania:
https://bibliotekanauki.pl/articles/1935814.pdf
Data publikacji:
2014
Wydawca:
Politechnika Gdańska
Tematy:
CABS
coarse-grained modeling
lattice model
mechanical unfolding of proteins
Opis:
Mechanical unfolding of the fourth domain of Distyostelium discoideum filamin ( DDFLN 4) was studied using a CABS – coarse-grained knowledge-based protein model. Our study demonstrates that CABS is capable of reproducing the unfolding free energy landscape of protein unfolding and highlights an important role of non-native interactions in the protein unfolding process. The obtained three peaks in the force-extension profile suggest a four-state picture of DDFLN 4 protein unfolding and correspond reasonably to the results of the all-atom simulation in explicit solvent.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2014, 18, 4; 373--378
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-100 z 231

Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies