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 "imperfection" wg kryterium: Temat

  Lista filtrów
Wyrównaj
Wyświetlanie 1-25 z 55
Tytuł:
Material Factors in Relation to Development Time in Liquid-Penetrant Inspection. Part 1. Material Factors
Autorzy:
Irek, P.
Słania, J.
Powiązania:
https://bibliotekanauki.pl/articles/351076.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
imperfection
defect
penetration testing
adhesion
Opis:
In technical publications and European Standards the development time (i.e. time of getting out of penetrant from a discontinuity to the material surface) in penetration testing is specified within the range of 10-30 minutes. In practice, however, it is seen , that it is closely connected with the material type and ranges from several minutes to 24 hours. In the literature, only interactions coming from the penetrant are described, whereas those from the material under testing, i.e. the influence of material factors on adhesion between penetrant and material, are not taken into consideration. In this connection, it has been described precisely in the paper the adhesion phenomenon and also it has been indicated the other factors affecting the development time. Recapitulating the adhesion theories presented in the paper, it can be formulated two fundamental circumstances which must occur that adhesion joint may be formed, namely: the approach of the particles of two solids to the distance less than 0,9 nm while the high attractive force occurring between molecules should be connected with possibly low potential energy of the bond formed in this way.
Źródło:
Archives of Metallurgy and Materials; 2016, 61, 2A; 509-514
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Material Factors in Relation to Development Time in Liquid-Penetrant Inspection. Part 2. Investigation Programme and Preliminary Tests
Autorzy:
Irek, P.
Słania, J.
Powiązania:
https://bibliotekanauki.pl/articles/353038.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
imperfection
defect
penetration testing
adhesion
Opis:
The paper is the continuation of the previous one entitled “Material factors in relation to development time in liquid-penetrant inspection. Part 1. Material factors” in which the material factors influencing essentially the development time in penetrant testing have been marked out. These are: type of material, surface roughness and imperfection width. In the paper it has been described how to prepare the factorial plan which will enable to test every factor with taking into account its different values. Moreover, it has been presented investigations on natural cracks, their width and roughness profile what will allow to assign suitable values of independent variables to the factorial plan. The purpose of the plan prepared in such a way will be the determination of the influence of the material kind, surface roughness and discontinuity width on the development time in penetrant testing.
Źródło:
Archives of Metallurgy and Materials; 2016, 61, 3; 1697-1708
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Material factors in relation to development time in liquid-penetrant inspection. Part 3. Testing of model plates
Autorzy:
Irek, P.
Słania, J.
Powiązania:
https://bibliotekanauki.pl/articles/356491.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
imperfection
defect
penetration testing
adhesion
Opis:
The paper is the continuation of the previous ones entitled „Material factors in relation to development time in liquid-penetrant inspection. Part 1. Material factors“ and „Material factors in relation to development time in liquid-penetrant inspection. Part 2. Investigation programme and preliminary tests“ in which material factors influencing essentially the development time in penetrant testing as well as the range of their values have been specified. These factors are: material kind, surface roughness and imperfection width. In the paper it has been described how far the development time in colour penetrant testing is influenced by an individual material factor. Moreover, it has been presented the equation being the function of material factors and development time.
Źródło:
Archives of Metallurgy and Materials; 2017, 62, 1; 41-49
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Elasto-plastic limit loads of cylinder-cone configurations
Sprężysto-plastyczne obciążenia graniczne w układach walcowo-stożkowych
Autorzy:
Dinkler, D.
Knoke, O.
Powiązania:
https://bibliotekanauki.pl/articles/279836.pdf
Data publikacji:
2003
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
stability
buckling
imperfection sensitivity
perturbation
plasticity
Opis:
The paper presents a procedure for computation of the limit loads of imperfection-sensitive shells including plastic deformations. On the basis of strain energy of shells, the worst case scenario for critical perturbations at fixed load levels is investigated. Limit loads of cylindrical and conical shells under combined actions are compared to European design rules. The concept is applied to more general buckling cases of combined shell structures.
W pracy przedstawiono metodę wyznaczania obciążeń granicznych dla powłok wrażliwych na niedoskonałości, z uwzględnieniem odkształceń plastycznych. Opierajac się na energii odksztalcenia powłok rozważono przypadek najgorszego scenariusza krytycznych perturbacji przy ustalonych poziomach obciążeń. Wartości obciążeń granicznych dla powłók cylindrycznych i stożkowych porównano z przyjętymi w Europie metodami projektowania. Koncepcja została zastosowana do analizy bardziej ogólnych przypadków utraty stateczności konstrukcji powłokowych.
Źródło:
Journal of Theoretical and Applied Mechanics; 2003, 41, 3; 443-457
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical equilibrium analysis of a stack of steel post pallets
Autorzy:
Pelc, J.
Powiązania:
https://bibliotekanauki.pl/articles/298177.pdf
Data publikacji:
2018
Wydawca:
Uniwersytet Warmińsko-Mazurski w Olsztynie
Tematy:
pallet
stack
equilibrium
stability
imperfection
warehouse
Opis:
A method for analyzing the equilibrium of a stack of loaded post pallets is presented. The finite element method was used to investigate the behavior of the bottom pallet in the stack during the addition of successive pallets. The stack was regarded as a self-stable multi-storey structure without bracings which is subjected to the weight of loaded pallets, horizontal forces resulting from sway and bow imperfections, and the impact of a forklift truck. The definite quadratic form of the tangent stiffness matrix after every increment in load was determined by nonlinear analysis to indicate the loss of post stability. An analysis of the stacking process of the evaluated pallets did not reveal a buckling trend in the posts of the bottommost pallet and demonstrated that the loss of equilibrium can lead to the collapse of the entire stack when a critical number of pallets is reached.
Źródło:
Technical Sciences / University of Warmia and Mazury in Olsztyn; 2018, 21(4); 271-280
1505-4675
2083-4527
Pojawia się w:
Technical Sciences / University of Warmia and Mazury in Olsztyn
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Rysuję bo muszę myśleć
I Draw Because I Have to Think
Autorzy:
Hecker, Zvi
Powiązania:
https://bibliotekanauki.pl/articles/97019.pdf
Data publikacji:
2019
Wydawca:
Politechnika Krakowska im. Tadeusza Kościuszki. Wydział Architektury. Instytut Projektowania Architektonicznego. Zakład Architektury Mieszkaniowej i Kompozycji Architektonicznej
Tematy:
rysunek
szkic
niedoskonałość
drawing
sketch
imperfection
Opis:
Tekst dotyczy rozszyfrowywania znaczenia rodzącej się koncepcji.
The text refers to decoding the meaning of a germinating concept.
Źródło:
Pretekst; 2019, 9; 23-24
2449-5247
Pojawia się w:
Pretekst
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Some selected FEM analyses of motion of a bullet with imperfections while interacting with the barrel
Autorzy:
Łazowski, J.
Małachowski, J.
Powiązania:
https://bibliotekanauki.pl/articles/243313.pdf
Data publikacji:
2008
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
barrel
bullet
simulation
movement modelling
imperfection
Opis:
The intended aim of studies on the modelling of a bullet interacting with a barrel is to generale a virtual, computer-based model, experimentally verified for some selected mating conditions, and to become able to predict -with strong probability - processes and phenomena that take place within a system with imperfections. In the case under consideration the problem of contact between the barrel and the bullet has been described with the calculation method based on the penalty function. Calculations were made using the so-called direct-integration procedurę, colloquially called the ,,explicit integration ". Preliminary analysis has been carried out on the effect of the shift of the centre ofmass of the bullet moving in the barrel. Simulation included the bullet displacement along the barrel's axis, with the assumed positions of the centre ofmass -5% and +5% as measured from the bottom and referred to the initial model (0%). Results ofnumerical calculations suggest the effect of shift of the bullet's centre of mass, which -when exposed to complex states of loading - experiences oscillating movements of the bottom and the tip. Additionally, this analysis proves that there is a complex state of stress due to compression, torsion, and bending of the bullet while interacting with the inner part of the barrel. Numerical solutions may support the analytically approached solving of such mechanical system. They may also offer more precise determination of, e.g. initial and boundary conditions for the bullet 's free flight, which is of great significance to the accuracy of fire, and therefore, to the weapons effectiveness.
Źródło:
Journal of KONES; 2008, 15, 1; 145-152
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Evaluation of Pore Sizes in Welded Joints Made in Various Constructional Materials on the Basis of Penetrant Testing by Colour Method
Autorzy:
Czuchryj, J.
Irek, P.
Powiązania:
https://bibliotekanauki.pl/articles/351921.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
imperfection
defect
penetrant testing
surface pores
Opis:
It has been compared the dimensions of indications obtained in colour liquid-penetrant inspection. The indications arose from simulated pores drilled in test elements. The series of penetrant tests included different structural materials. On the basis of test results it has been ascertained the possibility of evaluation of the pores depth as well as it has been determined recommended development times for different constructional materials.
Źródło:
Archives of Metallurgy and Materials; 2017, 62, 1; 19-25
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Buckling of imperfect thick cylindrical shells and curved panels with different boundary conditions under external pressure
Autorzy:
Alashti, R. A.
Ahmadi, S. A.
Powiązania:
https://bibliotekanauki.pl/articles/281593.pdf
Data publikacji:
2014
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
initial imperfection
buckling load
thick cylindrical panel
Opis:
In this paper, the effects of initial imperfections on the buckling behavior of thick cylindrical shells and curved panels are investigated. It is assumed that the shell has an axisymmetric and periodic initial imperfection in the axial direction. The shell is assumed to have different boundary conditions and subjected to pure external pressure loading. Governing differential equations are developed on the basis of the second Piola-Kirchhoff stress tensor and are re- duced to a homogenous linear system of equations using the differential quadrature method. The effects of different boundary conditions, geometric ratios, curvature and imperfection parameter on the buckling behavior of isotropic thick cylindrical shells and curved panels are carefully discussed. The results obtained by the present method are verified with finite element solutions and those reported in the literature.
Źródło:
Journal of Theoretical and Applied Mechanics; 2014, 52, 1; 25-36
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Imperfections in calculations of guyed lattice masts
Autorzy:
Matuszkiewicz, M.
Powiązania:
https://bibliotekanauki.pl/articles/230906.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
maszt z odciągami
analiza statyczna
imperfekcja geometryczna
imperfekcja początkowa
guyed mast
static analysis
geometric imperfection
initial imperfection
Opis:
Influence of geometric imperfections of mast shaft in form of initial mast span curvatures both on internal forces status in the structure elements as well as on those elements effort, which is particularly important at the design stage, was analysed based on an example of certain specific mast. The calculations were performed taking into account L/1000 imperfections equal to the permissible assembly deviations as per [1], and L/500 equal to initial imperfections as for uniform built-up columns according to [2]. Remarks and final conclusions have practical meaning and can be useful in design practice.
Źródło:
Archives of Civil Engineering; 2014, 60, 4; 409-420
1230-2945
Pojawia się w:
Archives of Civil Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Some selected examples of fem modelling of structure-affecting material and manufacturing faults
Autorzy:
Jachimowicz, J.
Małachowski, J.
Krasoń, W.
Kajka, R.
Powiązania:
https://bibliotekanauki.pl/articles/243333.pdf
Data publikacji:
2008
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
FEM modelling
combustion engine
landing gear
imperfection
Opis:
In design practice, in most of cases, stresses and deformations of structures with nominal dimensions and average material properties were analyzed. It have been concluded that such procedure is most often sufficient. However, there are design solutions, especially in high-effort structures for example aircraft and turbine engines, where scatter of geometrical dimensions consistent with assumed tolerances cause significant scatter of stresses and strains, differ from values coming from nominal dimensions. Scatter of these values have essential influence on service life of presented structures. Example of such effect is described in the paper. There were used FEM analyses to determination of scatter of stresses and stres s concentration coefficient in herringbone lock joint of K-15 engine's turbine. Another example of fault impact on stresses in structure is analysis of undercarriage element with material fault. Both these examples indicate on great sensitivity of stress distribution on manufacturing imperfections. The impact of these faults and imperfections reaches hundreds of per cent, and in some cases could be serious menace of operating safety. In structures with the multiple 3D stress state, non-linear geometric and material phenomena, with contact between friction-affected elements, any geometric imperfections can cause considerable local changes in the stress and strain.
Źródło:
Journal of KONES; 2008, 15, 1; 97-107
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Investigations of material behaviour under monotonic tension using a Digital Image Correlation system
Autorzy:
Szymczak, T.
Powiązania:
https://bibliotekanauki.pl/articles/281605.pdf
Data publikacji:
2018
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
geometrical imperfection
notch
extensometer
DIC
non-contact technique
Opis:
The paper reports behaviour of engineering materials for different kinds of notches, i.e. having U, V shapes. Their variants with respect to dimensions are illustrated in static and fatigue tests. The influence of these types of geometrical imperfections on material fatigue is presented using variations of the Wöhler curve, number of cycles to failure and the fatigue notch factor. Results of experiments conducted by the use of the Digital Image Correlation system called 4M Aramis are illustrated. Courses of tensile characteristics of the 41Cr4 steel, obtained by means of both techniques: extensometer and DIC are compared. They indicated that the DIC technique can be a good tool for determination of mechanical properties. The equivalent strain full-field distributions on specimens tensioned with and without imperfections up to material fracture are presented. The influence of U and V notches on variations of tensile curves is shown.
Źródło:
Journal of Theoretical and Applied Mechanics; 2018, 56, 3; 857-871
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Aquinas’ concept of change and its consequences for corporeal creatures
Autorzy:
Dziurosz-Serafinowicz, Dominika
Powiązania:
https://bibliotekanauki.pl/articles/427011.pdf
Data publikacji:
2014
Wydawca:
Uniwersytet Papieski Jana Pawła II w Krakowie
Tematy:
Aquinas’ philosophy
corporeal creatures
actualisation
potentiality
change
imperfection
Opis:
This paper is a presentation of Aquinas’ concept of change (lat. mutatio) and its consequences for corporeal creatures (lat. creatura corporali). Within Thomas’ philosophy, it can be proved that creatures are sentenced to unceasing change and cannot stop changing. That’s why the very purpose of change – full actualisation – is never attainable. Creatures are imperfect beings, and ex sui natura cannot attain perfection. Such a vision can lead to a conviction that the world of corporeal creatures is absurd. A short solution to the problem of absurdity is given with the use of Aquinas’ concept of participation. The structure of this paper is as follows. In the first section some basic limitations for the sake of this paper are made. In the second the concept of corporeal creatures is outlined. The third section analyses the definition of change. The fourth one presents various kinds of change. The next three are, respectively, proof of the creatures’ unceasing change, impossibility of full actualisation, and imperfection. The last one is an abbreviated presentation of the concept of participation as a reply to the question of the world’s absurdity.
Źródło:
Logos i Ethos; 2014, 1(36); 173-186
0867-8308
Pojawia się w:
Logos i Ethos
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A physical model of separation process by means of jigs
Autorzy:
Surowiak, A.
Brozek, M.
Powiązania:
https://bibliotekanauki.pl/articles/110846.pdf
Data publikacji:
2016
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
jigging process
physical model
Maxwell distribution
probable error
imperfection
Opis:
In the case of ideal separation of minerals, partition into products is conducted according to a specific partition feature which is, for instance, the density of raw material. Usually, enrichment in a jig is described by means of the particle density as a partition feature. However, the degree of particle loosening in the jig's bed is influenced by, among others, the particle free settling velocity. After some time of the pulsating movement duration, particle segregation along the vertical axis according to the settling velocity will occur. It can be said that the particle free settling velocity constitutes a feature characteristic of the feed heterogeneous in terms of physical and geometric properties in the jigging process. In the article on the basis of heuristic considerations, a physical model of the partition function (recovery of the i-th fraction), in which interactions between particles in the working bed of the jig are taken into account, is derived. A cause of the formation of the mechanism of particle dispersion around equilibrium layers is given and the accuracy of particle partition for a narrow size fraction in two variations, i.e. in conditions when a partition feature is, accordingly, the particle density and settling velocity, is calculated. These calculations allowed for the analysis of causes of process and inherent dispersion formation which takes place during the jigging process.
Źródło:
Physicochemical Problems of Mineral Processing; 2016, 52, 1; 228-243
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Językowe eksperymenty Jacka Dukaja i ich odzwierciedlenie w przekładzie (na materiale powieści Perfekcyjna niedoskonałość)
Jacek Dukaj’s linguistic experiments and their reflection in the translation (on the material of the novel Perfect imperfection)
Autorzy:
Kruglik, Paweł
Powiązania:
https://bibliotekanauki.pl/articles/51965605.pdf
Data publikacji:
2021-11-11
Wydawca:
Oficyna Wydawnicza ATUT – Wrocławskie Wydawnictwo Oświatowe
Tematy:
translation
Polish science fiction
Perfect imperfection
linguistic experiments
Dukaj
Opis:
This article is devoted to the problem of translating science fiction. Such problems are usually determined by the fact that the texts of this genre are repleted with scientific terminology, descriptions of new technologies and their application. The world depicted in fantastic literature has a typical ontological status. In order to achieve the desired adequacy, the translator must demonstrate not only knowledge of the principles of fiction translation but also additional competencies. The material for the analysis comes from the novel Perfect imperfection by Jacek Dukaj is an example of science fiction literature, orientated to technological progress ideas. This novel can be studied in a multifaceted way. In this article, however, the research area has been narrowed down to some linguistic innovation and language games, which will be analyzed in the Polish-Russian translation aspect.
Źródło:
Studia Translatorica; 2021, 12; 193-204
2084-3321
2657-4802
Pojawia się w:
Studia Translatorica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Detection of Monocrystalline Silicon Wafer Defects Using Deep Transfer Learning
Autorzy:
Ganum, Adriana
Iskandar, D. N. F. Awang
Chin, Lim Phei
Fauzi, Ahmad Hadinata
Powiązania:
https://bibliotekanauki.pl/articles/2058502.pdf
Data publikacji:
2022
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
automated optical inspection
machine learning
neural network
wafer imperfection identification
Opis:
Defect detection is an important step in industrial production of monocrystalline silicon. Through the study of deep learning, this work proposes a framework for classifying monocrystalline silicon wafer defects using deep transfer learning (DTL). An existing pre-trained deep learning model was used as the starting point for building a new model. We studied the use of DTL and the potential adaptation of Mo bileNetV2 that was pre-trained using ImageNet for extracting monocrystalline silicon wafer defect features. This has led to speeding up the training process and to improving performance of the DTL-MobileNetV2 model in detecting and classifying six types of monocrystalline silicon wafer defects (crack, double contrast, hole, microcrack, saw-mark and stain). The process of training the DTL-MobileNetV2 model was optimized by relying on the dense block layer and global average pooling (GAP) method which had accelerated the convergence rate and improved generalization of the classification network. The monocrystalline silicon wafer defect classification technique relying on the DTL-MobileNetV2 model achieved the accuracy rate of 98.99% when evaluated against the testing set. This shows that DTL is an effective way of detecting different types of defects in monocrystalline silicon wafers, thus being suitable for minimizing misclassification and maximizing the overall production capacities.
Źródło:
Journal of Telecommunications and Information Technology; 2022, 1; 34--42
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Niezgodności fizykochemiczne między składnikami produktów leczniczych
Autorzy:
Wesołowski, M.
Powiązania:
https://bibliotekanauki.pl/articles/274152.pdf
Data publikacji:
2012
Wydawca:
Roble
Tematy:
leki
produkt leczniczy
jakość leku
interakcje fizykochemiczne
niezgodność fizyczna
niezgodność chemiczna
medicine
medicinal products
medicine quality
physicochemical interaction
physical imperfection
chemical imperfection
Źródło:
LAB Laboratoria, Aparatura, Badania; 2012, 17, 1; 19-22
1427-5619
Pojawia się w:
LAB Laboratoria, Aparatura, Badania
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On the method of calculation of buckling and post-buckling behavior of laminated shells with small arbitrary imperfections
O metodzie obliczania wyboczenia i stanu powyboczeniowego dla powłok z małymi imperfekcjami
Autorzy:
Semenyuk, M.
Trach, V.
Zhukova, Z.
Powiązania:
https://bibliotekanauki.pl/articles/2084048.pdf
Data publikacji:
2021
Wydawca:
Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Wydawnictwo Szkoły Głównej Gospodarstwa Wiejskiego w Warszawie
Tematy:
buckling
post-buckling
imperfection
laminated shell
mode interaction
Cauchy problem
Opis:
In the present paper the variant of computational methods of stability and initial post-buckling behavior of isotropic shells was generalized with respect to laminated composite shells. Using methods of the asymptotic analysis of the Timoshenko–Mindlin theory, the relationships for calculation of shells with the small geometrical imperfections of the different shapes have been produced. On the basis of obtained equations, the technique of calculation of a non-linear pre-buckling state, limiting loads and bifurcation, and also initial post-buckling behavior of laminated cylindrical shells at an axial compression and external pressure have been worked out. The results of calculation for the shells made of glass fiber-reinforced plastic and carbon fiber-reinforced plastic with multimodal imperfections and dimple imperfections have been presented. The features of transformation of the interacting modes of imperfections have been researched.
Źródło:
Acta Scientiarum Polonorum. Architectura; 2021, 20, 2; 17-25
1644-0633
Pojawia się w:
Acta Scientiarum Polonorum. Architectura
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Defects Appearing in the Surfacing Layers of Abrasion Resistant
Autorzy:
Bęczkowski, R.
Gucwa, M.
Powiązania:
https://bibliotekanauki.pl/articles/381038.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
imperfection
surfacing
metallography
hardfacing
quality
wadliwość
proces napawania
metalografia
jakość odlewu
Opis:
The surfacing technologies are used for constitution of protection layer against wear and is destined for obtaining coating with high hardness. Among many weldings methods currently used to obtain the hard surface layer one of the most effective way of hardfacing is using flux cored arc welding. This additional material gives more possibilities to make expected hard surface layer. Chemical composition, property and economic factors obtained in flux cored wire are much richer in comparison to these obtained with other additional materials. This is the reason why flux cored wires give possibilities of application this kind of material for improving surface in different sectors of industry. In the present paper the imperfection in the layers was used for hardfacing process in different situations to show the possible application in the surface layer. The work presents studies of imperfection of the welds, contains the picture of microstructures, macrostructures and shows the results of checking by visual and penetrant testing methods.
Źródło:
Archives of Foundry Engineering; 2016, 16, 4; 23-28
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Klassifikacija kharakternykh necovershenstv zernovykh sejalok i napravlenija ikh ustranenija
Classification of distinctive imperfections of grain seeders and directions of their eliminations
Autorzy:
Rublyov, V.
Opalko, V.
Powiązania:
https://bibliotekanauki.pl/articles/78102.pdf
Data publikacji:
2013
Wydawca:
Komisja Motoryzacji i Energetyki Rolnictwa
Tematy:
cereal seeder
seeder
quality improvement
distinctive imperfection
quality management system
technical condition
Opis:
Определены характерные несовершенства зерновых сеялок и установлены причины их возникновения. Представлена классификация несовершенств посевных машин и разработаны предложения по их устранению. Приведенные примеры реализации предложений по улучшению качества зерновых сеялок.
Distinctive imperfections of grain seeders were determined and causes of their origin were established. Classification of imperfections of sowing machines was presented and proposals of their elimination were developed. Examples of proposals realization on improvement of grain seeders quality are given.
Źródło:
Motrol. Motoryzacja i Energetyka Rolnictwa; 2013, 15, 3
1730-8658
Pojawia się w:
Motrol. Motoryzacja i Energetyka Rolnictwa
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Assessment of buckling behaviour on an FPSO deck panel
Autorzy:
Ozguc, Ozgur
Powiązania:
https://bibliotekanauki.pl/articles/1585047.pdf
Data publikacji:
2020
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
buckling strength
imperfection sensitivity
nonlinear finite element analysis
FPSO unit
deck panel
Opis:
Stiffened plates are the main structural building block in ship and offshore hulls and their structural response subject to loads is a topic of significant practical interest in ship and offshore structural design. To investigate the structural capacity for design and evaluation purposes, it is becoming an efficient and reliable practice to carry out non-linear finite element (FE) analysis. The present study is to assess the buckling strength of a stiffened deck panel on an FPSO vessel using the nonlinear finite element code ADVANCE ABAQUS, where imperfection sensitivity work is also accounted for. The cases studied correspond to in-plane bi-axial compression in the two orthogonal directions. The findings are compared with the DNVGL PULS (Panel Ultimate Limit State) buckling code for the stiffened panels. It is found that the strength values from the ADVANCE ABAQUS and DNVGL PULS code are very close. The results and insights developed from the present work are discussed in detail.
Źródło:
Polish Maritime Research; 2020, 3; 50-58
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Badania eksperymentalne wpływu deformacji ładunku kumulacyjnego na zmniejszenie skuteczności strumienia kumulacyjnego
Experimental studies of shaped charge deformation impact on reduction shaped charge jet efectiveness
Autorzy:
Panowicz, R.
Kołodziejczyk, D.
Szymańczyk, L.
Powiązania:
https://bibliotekanauki.pl/articles/234815.pdf
Data publikacji:
2013
Wydawca:
Wojskowy Instytut Techniczny Uzbrojenia
Tematy:
ładunek kumulacyjny
strumień kumulacyjny
imperfekcja ładunku
shaped charge
shaped charge jet
imperfection
Opis:
W poniższej pracy przedstawione zostały wyniki badań eksperymentalnych wpływu deformacji ładunku kumulacyjnego na zmniejszenie skuteczności strumienia kumulacyjnego. Celowo utworzone deformacje ładunku wpłynęły na imperfekcje wkładki kumulacyjnej oraz materiału wybuchowego. Efektem tego była utrata symetrii w osi ładunku. Imperfekcje te miały niekorzystny wpływ na proces tworzenia się strumienia kumulacyjnego, co udało się potwierdzić opisanymi poniżej badaniami eksperymentalnymi. Wytworzone sztucznie deformacje ładunku kumulacyjnego uformowane były na wzór deformacji, jakie mają miejsce podczas zderzenia pocisku typu PG 7 z ochronnym pancerzem prętowym. Zostało to wcześniej potwierdzone przeprowadzeniem odpowiednich badań poligonowych w ramach projektu obrony pasywnej pojazdów. Przedstawione poniżej badania można więc potraktować jako kontynuację tych prac w kontekście zjawiska kumulacji. Są one również potwierdzeniem skuteczności pancerza prętowego, pokazując jak niewielka deformacja ładunku kumulacyjnego skutecznie zaburza cały proces kumulacji. Praca ta pozwala wnioskować, że do skutecznego zaburzenie strumienia kumulacyjnego wystarczająca jest deformacja ładunku bez konieczności jego uszkadzania w postaci nieciągłości materiału (rozerwania zewnętrznego poszycia, wkładki lub materiału wybuchowego).
The basic aim of the paper is to presents the results of experimental studies of the shaped charge deformation impact on the reduction of the shaped charge jet. Imperfections of a cumulative liner, explosives and a cover were introduced intentionally. The imperfection resulted in the loss of symmetry in the axis of the charge. These imperfections have an adverse effect on the formation of the shaped charge jet, which was confirmed by experimental studies described below. Deformations introduced into the shape charge corresponded to the situations that take place during an interaction between PG 7 missile and a slat armour. It was previously confirmed by suitable field tests within the frameworks of the project of passive defence of vehicles against a missile with a shape charge warhead. The following tests may therefore be regarded as a continuation of these works in the context of the influence of the interaction between PG 7 missile and the slat armour on the phenomenon of the shaped charge jet. They also confirm the effectiveness of the bar armour, showing how a small deformation of the shape charge effectively interferes with the jet formation. This work allows us to conclude that the effective disorder of the shape charge jet formation is sufficient distortion of the charge without damage (rupture of the outer skin, liner or explosive).
Źródło:
Problemy Techniki Uzbrojenia; 2013, 42, 126; 41-48
1230-3801
Pojawia się w:
Problemy Techniki Uzbrojenia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of brace stiffness influence on stability of the truss
Autorzy:
Krajewski, M.
Iwicki, P.
Powiązania:
https://bibliotekanauki.pl/articles/266180.pdf
Data publikacji:
2015
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
buckling load
limit load
brace stiffness
imperfection
kratownica
analiza numeryczna
konstrukcje stalowe
Opis:
The paper is devoted to the numerical and experimental research of stability of a truss with side elastic supports at the top chord. The structure is a model of a real roof truss scaled by factor ¼. The linear buckling analysis and non-linear static analysis were carried out. The buckling length factor for the compressed top chord was calculated and the limit load for the imperfect truss shell model with respect to brace stiffness was obtained. The relation between brace normal force and loading of the truss is presented. The threshold stiffness of braces necessary to obtain the maximum buckling load was found. The truss load bearing capacity obtained from numerical analysis was compared with Eurocode 3 requirements.
Źródło:
International Journal of Applied Mechanics and Engineering; 2015, 20, 1; 97-108
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Probabilistic analysis of a space truss by means of multidimensional variable description
Probabilistyczna analiza przestrzennej kratownicy opisanej wielowymiarową zmienną losową
Autorzy:
Sorn, P.
Górski, J.
Przewłócki, J.
Powiązania:
https://bibliotekanauki.pl/articles/231181.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
teoria niezawodności
metoda estymacji rozkładem dyskretnym
kratownica przestrzenna
imperfekcja geometryczna
imperfekcja materiałowa
analiza nośności granicznej
reliability theory
point estimated method
space truss
geometric imperfection
material imperfection
limit load analysis
Opis:
Probabilistic analysis of a space truss is presented in the paper. Reliability of such a structure is sensitive to geometrical and material imperfections. The objective of this paper is to present a variant of the point estimate method (PEM) to determine mean values and standard deviations of limit loads of engineering structures. The main advantage presented by this method is the small number of sample calculations required to obtain estimators of investigated parameters. Thus the method is straightforward, requiring only preliminaries of probability theory. This approach is illustrated by limit state analysis of a space truss, considering geometric and material imperfections. The calculations were performed for different random models, so the influence of random parameters on the limit load of the truss can be determined. A realistic snow load was imposed.
W pracy przedstawiono probabilistyczną analizę kratownicy przestrzennej. Obciążenia graniczne tego typu konstrukcji są wrażliwe na odchyłki geometryczne oraz zmiany parametrów materiałowych. W obliczeniach niezawodności stosowanych jest wiele metod: metoda Monte Carlo, metody redukujące liczbę realizacji (np. metoda próbkowania warstwowego i hipersześcianu łacińskiego), metoda powierzchni odpowiedzi, sieci neuronowych i inne. Metoda Monte Carlo nie narzuca żadnych ograniczeń na analizowane problemy ale jej zastosowanie wymaga czasochłonnych obliczeń. Z kolei efektywne metody redukcyjne podlegają trudnym do zdefiniowania ograniczeniom. Często stosowane są tzw. metody pierwszego i drugiego rzędu (FORM, SORM), jednakże w praktyce znajdują one zastosowanie jedynie w określonej klasie zagadnień. Efektywne rozwiązanie można też uzyskać wykorzystując metodę estymacji rozkładem dyskretnym (PEM – Point Estimate Method).
Źródło:
Archives of Civil Engineering; 2015, 61, 2; 99-123
1230-2945
Pojawia się w:
Archives of Civil Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Estimation of buckling response of the deck panel in axial compression
Autorzy:
Ozguc, O.
Powiązania:
https://bibliotekanauki.pl/articles/258946.pdf
Data publikacji:
2018
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
buckling failure
non-linear finite element analysis
deck panel
initial imperfection
collapse mechanism
Opis:
In this work, buckling strength assessment of a deck of a double hull oil tanker is carried out using the non-linear finite element code ADVANCE ABAQUS. The comparisons are performed with the Det Norske Veritas (DNV-GL) PULS (Panel Ultimate Limit State) buckling code for the stiffened panels, DNV-GL Classification Notes (CN) No.30.1 and the DNV-GL Ship Rules. The case studied corresponds to axial compression. Two levels of imperfection tolerances are analyzed, in accordance with the specifications in the DNV-GL Instruction to Surveyors (IS) and the DNV-GL Classification Notes No. 30.1. Both “as built” and DNV–GL Rule “net” dimensions are analyzed. The strength values from ADVANCE ABAQUS and PULS are very close. DNV-GL CN 30.1 is in conservative side, but the strength differences between the “as built” and “net” dimension cases are consistent with the finite element analysis results. This paper gives a brief description of the background for the stiffened panel models used in PULS, and comparison against non-linear FE analysis, and DNV-GL Classification Society Rules. The finite element code ADVANCE ABAQUS is employed in a non-linear buckling analysis of a stiffened deck panel on a double skin tanker that is subjected to a Condition Assessment Program (CAP) hull survey. The aim of the analyses has been to validate and compare the buckling capacity estimates obtained from PULS, DNV-GL Classification Notes No.30.1 (CN 30.1) and the DNV-GL Ship Rules.
Źródło:
Polish Maritime Research; 2018, 4; 98-105
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-25 z 55

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