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Tytuł:
Elementy budowy geologicznej zachodniej części wielickiego złoża solnego w świetle badań grawimetrycznych
Elements of geological structure of the west part of Wieliczka salt deposit in the light of gravity survey
Autorzy:
Łój, M.
Powiązania:
https://bibliotekanauki.pl/articles/183650.pdf
Data publikacji:
2009
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
badania grawimetryczne
modelowanie grawimetryczne
rozkład rezydualny
gravity survey
gravity modelling
schedule of residual gravity
Opis:
Interpretation of made gravity survey permitting to put forward a motion about geological structure of the rock mass is a topic of the introduced work and the attempt of its quantitative epithet. To this purpose quantitative and qualitative analysis was carried of schedule of the anomaly of the gravity and on this base a big usefulness of gravimetric examinations was introduced in recognizing the geological building site of this area.
Źródło:
Geologia / Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie; 2009, 35, 2/1; 413-420
0138-0974
Pojawia się w:
Geologia / Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Computer modelling of the ablation casting process and prediction of the strength properties of AC-42000 castings
Autorzy:
Małysza, Marcin
Puzio, Sabina
Major-Gabryś, Katarzyna
Głowacki, Mirosław
Wilk-Kołodziejczyk, Dorota
Kamińska, Jadwiga
Powiązania:
https://bibliotekanauki.pl/articles/29520071.pdf
Data publikacji:
2022
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
casting
simulations
ablation
gravity sand casting
gravity die casting
mechanical properties
Opis:
The demand for castings with superior properties has compelled the development and optimization of manufacturing technologies. By further developing already known techniques, we are able to contribute to the introduction of new research possibilities. The article presents the methodology of conducting simulation tests of the gravity casting process into sand moulds with the use of ablation. The ablation technique consists in spraying water through evenly spaced nozzles onto a mould into which the liquid casting alloy has been poured. The conducted research focuses on an alloy from the group of Al-Si alloys. In order to compare the effects of different techniques, additional tests were carried out for gravity casting into sand and metal die moulds. At the same time, virtual experiments were conducted to develop a simulation methodology for ablation casting technology, taking into account mould degradation. Additionally, the possibility of predicting the final mechanical properties of various manufacturing technologies was tested. Destructive tests were carried out to determine the mechanical properties in the cast samples, as well as microstructure tests and secondary dendrite spacing. The results of the mechanical tests are compared with the predicted simulation properties.
Źródło:
Computer Methods in Materials Science; 2022, 22, 2; 79-88
2720-4081
2720-3948
Pojawia się w:
Computer Methods in Materials Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Gauge Model for Gravity and considerations on the Asymmetry of Time and the SU (2) Mass Gap
Autorzy:
Kabe, Koustubh
Powiązania:
https://bibliotekanauki.pl/articles/1178329.pdf
Data publikacji:
2017
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Gauge theory
general relativity
gravity
loop quantum gravity
mass gap
quantum field theory
quantum gravity
string theory
super gravity (SUGRA)
super symmetry (SUSY)
time
time asymmetry
Opis:
A new formulation of the Hamiltonian formalism of general relativity is developed based on the adiabatic variation of the Hamiltonian constraint. This new formulation consists of complex valued anti-Hermitian 1- called the Berry gauge potentials. These are then used to develop the complex Berry-Einstein-Yang-Mills curvature 2- . The Berry-Yang-Mills field equations are then developed and interpreted in a novel manner to incorporate quantum temporal strings in the non-perturbative formalism. This is however just highlighted in this paper and will be pursued in another paper. Since, the holonomy phase construed is that of Lorentz rotation we perceive a new quantum structure of the space-time namely that of causality. The future light cones are soldered internally to the tensor fields naturally so that the Berry-Ehresmann connection defines a quantum gauge field of causality. This field evokes the causal structure attributed to space-time as gauge degrees of freedom of quantum space ― a fluid of future light cones. This symmetry being of the gauge field type has three generators i.e., three gauge bosons― all heavy and therefore attracted by gravity. Thus causality is a local gauge degree of freedom of gravity. Once the theory is developed, the problem of the mass gap is considered for our gauge field. It seems that the problem is solved in this paper.
Źródło:
World Scientific News; 2017, 81, 2; 198-220
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Actual picture of the law of universal gravitation and the quantum gravity theory describing the real state of the universe
Autorzy:
Borowski, T.
Powiązania:
https://bibliotekanauki.pl/articles/412595.pdf
Data publikacji:
2013
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
classical gravity theory
quantum gravity theory
dark matter
Copernicus
Newton
Opis:
This paper presents the real sense of the classical and quantum theory of gravitation as a component of the actual picture of the universe where the volume, as the size of the expanding universe, approaches infinity, while the total of material masses goes to zero. At present, these two standard theories describe the phenomenon of gravitation but do not explain the very mechanism and the cause of this process. This constant and real lack of information on that subject is consistent with natural laws and the same with the laws of physics, which were already experimentally determined by Werner Heisenberg in 1927. The paper also presents the causes of inability to explain up to the present the actual picture of the essence of the universe.
Źródło:
International Letters of Chemistry, Physics and Astronomy; 2013, 11; 44-53
2299-3843
Pojawia się w:
International Letters of Chemistry, Physics and Astronomy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Horizontal motion of a rigid block resting on accelerating subsoil
Autorzy:
Sawicki, A.
Chybicki, W.
Powiązania:
https://bibliotekanauki.pl/articles/241061.pdf
Data publikacji:
2005
Wydawca:
Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN
Tematy:
vibrations
earthquake
gravity structure
Opis:
The horizontal motion of the system: rigid block-accelerating subsoil is analysed, using the most simple approach. First, the method of analysis is described and illustrated for constant coefficient of friction between the block and subsoil. Then, the changing coefficient of friction is taken into account, and its influence on the motion shown. In the next step of analysis, the influence of horizontal force on permanent relative displacement of the block with respect to subsoil is illustrated for constant and changing coefficients of friction. The method presented in this paper form a basis for critical discussion of the Newmark approach, that is a kind of standard in earthquake geotechnics.
Źródło:
Archives of Hydro-Engineering and Environmental Mechanics; 2005, 52, 2; 147-160
1231-3726
Pojawia się w:
Archives of Hydro-Engineering and Environmental Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Exploration and characterization of barite mineral from Azara-Nassarawa ore deposits from suitabiity in industrial applications
Autorzy:
Nzeh, Nnaemeka Stanislaus
Popoola, Patricia Abimbola
Powiązania:
https://bibliotekanauki.pl/articles/24085980.pdf
Data publikacji:
2023
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
barite
mineral ore
Azara-Nassarawa
gravity concentration
jigging
tabling
concentrate
recovery
specific gravity
Opis:
Primary concentrations of Azara barite deposit in Nassarawa state, Nigeria were conducted; employing simplified gravity concentration techniques. Particle size distribution, specific gravity, physicochemical and morphological analyses of the sample was conducted. These analyses were done in order to establish process efficacy and effectiveness of gravity concentration processes for recovery of barium from the ore deposit, as well as its suitability in various industrial applications, such as the oil and gas sectors. Thus, microstructural, chemical composition and certain physicochemical characteristics/properties of the mineral sample of Azara-Nassarawa barite were determined. XRD, XRF, SEM and EDS analyses were utilized in determining morphology as well as quantitative and qualitative chemical analyses of the sample. Barite sample with average particle size of -355+150μm was subjected to concentration, adopting jigging and tabling gravity separation as the concentration methods. Hitherto, based on quantitative and qualitative chemical analyses conducted, the sample was composed of about 36.2% BaO and 40.5% Ba, respectively; and also possessed an average specific gravity (SG) of about 3.85. Further, the qualitative analysis of the mineral products of jiggling and tabling indicated that jigging had a concentrate recovery of 130.98% Ba with SG increase of 11.2% while tabling had 89.81% Ba recovery with 8.6% SG increase. Assay and SG results confirm gravity concentration efficiency and thus, establish the barite from Azara-Nassarawa ore deposits suitable for certain industrial applications. This will serve as a tool and a step further towards mitigating existing problems or challenges in mineral concentration and processing of such deposits for industrial purposes.
Źródło:
Physicochemical Problems of Mineral Processing; 2023, 59, 2; art. no. 166104
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Lithospheric structure across the Trans-European Suture Zone in NW Poland based on gravity data interpretation
Autorzy:
Królikowski, C.
Petecki, Z.
Powiązania:
https://bibliotekanauki.pl/articles/2059901.pdf
Data publikacji:
2002
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
Trans-European Suture Zone
gravity anomalies
structural-density model
gravity stripping
lithospheric structure
Opis:
We provide an analysis of geophysical and geological data from the Baltic segment of the Trans-European Suture Zone (TESZ). The construction of structural and density maps of the Zechstein-Mesozoic-Cenozoic complex has allowed identification of anomalies of basement orgin. As a result of interpretation of these anomalies, major structural elements of the lithosphere have been characterised. According to gravity modelling the crustal structure is more complicated than shown on velocity model along refraction and wide-angle reflection profile LT-7. Long-wavelength anomalies have been modelled in terms of lateral heterogeneity within the lower crust and upper mantle. In order to achieve a match between the observed and calculated gravity effects, it was necessary to assume dense upper mantle beneath the TESZ. Gravity data also indicate the presence of high-density bodies in the upper crust, and a complex transitional zone between crust and upper mantle in the TESZ.
Źródło:
Geological Quarterly; 2002, 46, 3; 235-246
1641-7291
Pojawia się w:
Geological Quarterly
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study of the Variations in the Vertical and Horizontal Distribution of Heavy Sand Minerals in the Hilla River Sediments
Autorzy:
Hameed, Iman A.
Rahman, Haleema Abdul Jabbar Abdul
Anmar, Alsaadi
Powiązania:
https://bibliotekanauki.pl/articles/27323812.pdf
Data publikacji:
2023
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
sediment
heavy minerals
specific gravity
Opis:
This study was conducted to investigate the effect of the Hilla River sediments on the heterogeneity of the distribution of heavy sand minerals for the fine and very fine sand classes as well as for the surface and subsurface layers. The results showed that the heavy sand minerals that were determined according to the specific gravity of each mineral and the specific gravity of the particles of minerals identified in the soils under study ranged between (2.5–4.5) and were divided into four groups in terms of the specific gravity. The first group included each of the minerals (Mica and Chlorite) of low specific gravity, while the second group contains (Pyroxene, Amphibole, Epidote Group). The third group includes minerals (Tourmaline and Garnet, Staurolite and Kyanite) and the two groups are classified as minerals of medium-specific gravity; in turn, the fourth group contains minerals of high specific gravity, namely (Zircon, Rutile and Opaques). As a result, the most important factors affecting the sedimentation, sorting and sedimentation processes are the conveyor’s speed, load capacity, the size of the separation particles and their specific gravity. The complete mismatch of the horizontal distribution of the minerals of one group is due to the varying ranges of the specific gravity of the minerals within the general range of specific gravity.
Źródło:
Journal of Ecological Engineering; 2023, 24, 7; 318--330
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Use of Falcon Concentrator to Determine the Gravity Recoverable Gold (GRG) Content in Gold Ores
Zastosowanie wzbogacalnika typu Falcon do określenia zawartości złota w produkcie ze wzbogacania grawitacyjnego (test GRG) dla rud złota
Autorzy:
Onel, O.
Tanriverdi, M.
Powiązania:
https://bibliotekanauki.pl/articles/971117.pdf
Data publikacji:
2016
Wydawca:
Polskie Towarzystwo Przeróbki Kopalin
Tematy:
test GRG (gravity recoverable gold)
wirówka
wstępne wzbogacanie
wzbogacalnik typu Falcon
gravity recoverable gold
centrifugal gravity concentrator
preconcentration
Falcon concentrator
Opis:
This study presents the results of the application of the laboratory gravity-recoverable-gold (GRG) determination procedure on a Turkish gold ore using a Falcon concentrator. The study had two major goals; as investigating the compatibility of Falcon concentrator for GRG procedure (which was originally developed for Knelson concentrator); and finding out the gravity recoverable gold content in Gümüşhane/Mastra gold ore. It was seen that a concentrate enriched in Au content could be successfully achieved: After the first stage a product with an Au grade of 41.09 mgAu/tonne at %10.95 fractional gold recovery at the first stage of the procedure. Au content in the concentrate increased to 98.84 mg after the second stage and finally 59.74 mg Au was obtained by the third stage. As a result of the application, it was found that the GRG content of Gümüşhane/Mastra gold was 48.28%, corresponding to a significant potential for obtaining an Au-enriched preconcentrate.
Artykuł przedstawia wyniki zastosowania procedury laboratoryjnego testu GRG (wzbogacania grawitacyjnego) dla tureckich rud złota za pomocą wzbogacalnika typu Falcon. Badania miały dwa główne cele: zbadanie przydatności wzbogacalnika typu Falcon do testu GRG (który został opracowany oryginalnie dla wzbogacalnika typu Knelson) oraz określenie zawartości złota w produkcie ze wzbogacania grawitacyjnego dla rudy złota ze złoża Gümüşhane/Mastra. Stwierdzono, że produkt o dużej zawartości Au może zostać osiągnięty. Po pierwszym etapie otrzymano produkt o zawartości Au równej 41,09 mg przy uzysku frakcjonowanym złota równym 10,95% przy pierwszym stadium testu. Zawartość Au w koncentracie wzrosła do 98,84 mg po drugim etapie a finalnie otrzymano zawartość Au równą 59,74 mg po etapie trzecim. W wyniku zastosowania eksperymentu stwierdzono, że zawartość GRG złota ze złoża Gümüşhane/Mastra wyniosła 48,28% a ponadto stwierdzono wysoki potencjał do otrzymania wstępnych koncentratów bogatych w Au.
Źródło:
Inżynieria Mineralna; 2016, R. 17, nr 1, 1; 189-194
1640-4920
Pojawia się w:
Inżynieria Mineralna
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Evaluation by Multi Gravity Separator (MGS) of a Low Grade Chromite Tailing From Yesilova-Burdur (Turkey)
Ocena za pomocą separatora grawitacyjnego (MGS) odpadowego chromitu niskiej jakości z Yesilova-Burdur (Turcja)
Autorzy:
Deniz, Vedat
Powiązania:
https://bibliotekanauki.pl/articles/318359.pdf
Data publikacji:
2019
Wydawca:
Polskie Towarzystwo Przeróbki Kopalin
Tematy:
chromit
odpady
separator wielograwitacyjny MGS
wzbogacanie
grawitacja
chromite
tailings
multi gravity separator
beneficiation
gravity
Opis:
In this study, concentrability by a Multi-Gravity-Separator (MGS) of the chromite tailings with content 23.84% Cr2O3 from Yeşilova-Burdur (Turkey) is investigated. Mineralogical analyses showed that the chromite tailings contain chromite and serpentine which formed as a result of alteration of serpantine group minerals such as olivines, chrysotile and talc. The tailings generated from chromite beneficiation plants in Turkey are generally concentrated by slime tables (Deister shaking tables) for producing the desirable saleable grade. However, slime tables are concentrating with low recovery for chromite minerals which are very fine particle size. MGS is an efficient method for separation of minerals by gravity at very fine particle size. In experimental studies, the effects of feed rate, washwater rate, drum speed and tilt angle, which are important for operating parameters of MGS observed for the low grade chromite tailings were investigated. As a result of the experimental studies performed, it was obtained a concentrate with saleable chromite grade and recovery from the tailings which is having size fraction under 0.075 mm.
W artykule przedstawiono wzbogacalność w separatorze grawitacyjnym (MGS) odpadów chromitowych o zawartości 23,84% Cr2O3 z Yeşilova-Burdur (Turcja). Analizy mineralogiczne wykazały, że odpady chromitowe zawierają chromit i serpentyn, które powstały w wyniku zmian minerałów z grupy serpenitu, takich jak oliwiny, chryzolit i talk. Odpady wytwarzane w zakładach wzbogacania chromitu w Turcji są na ogół wzbogacanie na stołach koncentracyjnych dla drobnych ziaren (stoły wytrząsające Deister) w celu uzyskania produktu nadającego się do sprzedaży. Jednak stoły koncentracyjne się charakteryzują się z niskim uzyskiem minerałów chromitowych o drobnym uziarnieniu. MGS to skuteczna metoda wydzielania grawitacyjnego bardzo drobnych cząstek. W badaniach eksperymentalnych zbadano wpływ prędkości podawania, prędkości wody do wzbogacania, prędkości bębna i kąta pochylenia, które są ważne dla parametrów operacyjnych MGS badanych odpadów chromitowych niskiej jakości. W wyniku przeprowadzonych badań eksperymentalnych uzyskano z odpadów o uziarnieniu poniżej 0,075 mm koncentrat chromitu o jakości handlowej.
Źródło:
Inżynieria Mineralna; 2019, 21, 1/2; 101-106
1640-4920
Pojawia się w:
Inżynieria Mineralna
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Calculation of a stripped gravity map with a high degree of accuracy: a case study of Liptovská Kotlina Basin (Northern Slovakia)
Autorzy:
Szalaiová, E.
Bielik, M.
Makarenko, I.
Powiązania:
https://bibliotekanauki.pl/articles/2060228.pdf
Data publikacji:
2008
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
pre-Tertiary basement
Central Carpathian Paleogene
Liptovská Kotlina Basin
gravity
stripped gravity map
2D and 3D forward-modelling gravity
Opis:
The paper deals with the construction and calculation of a stripped gravity map with a high de gree of accu acy. In the Western Carpathian basins such types of gravity maps represent the corrected Bouguer anomalies by the gravity effects of the Tertiary sedimentary masses. It means that the re sultant stripped gravity map reflects the gravity effects of den sity inhomogeneities, which are located beneath the pre-Tertiary basement. For determination of this map, the modern progres sive forward-mod elling gravity method was applied. The advantage of this method in comparison with previous approaches is that it is capable of calculating the 3D gravity effects of the geological bodies with real topography. A case study for presentation of a new and precise stripped gravity map, the Liptovská Kotlina Basin, was chosen, because it is one of the best-surveyed basins in the West ern Carpathians. This new gravity map represents, for this moment, the most accurate stripped gravity map in the whole Western Carpathians. It allows construction not only of a very precise 3D gravity model of the sedimentary fill but also enables interpretation of the sources of the gravity anomalies revealed in the stripped gravity map. This interpretation is based on all available geophysical and geological constraining data. It is also supported by 2D analysis of the gravity effects of the main tectonic units building the Liptovská Kotlina Basin.
Źródło:
Geological Quarterly; 2008, 52, 2; 103-103
1641-7291
Pojawia się w:
Geological Quarterly
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
New gravity control in Poland – needs, the concept and the design
Nowa osnowa grawimetryczna w Polsce – potrzeby, koncepcja i projekt
Autorzy:
Kryński, J.
Olszak, T.
Barlik, M.
Dykowski, P.
Powiązania:
https://bibliotekanauki.pl/articles/145356.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
hydrologia lokalna
osnowa grawimetryczna
pomiary grawimetryczne
gravity control
absolute gravity determination
local hydrology
Opis:
The existing Polish gravity control (POGK) established in the last few years of 20th century according to the international standards is spanned on 12 absolute gravity stations surveyed with four different types of absolute gravimeters. Relative measurements performed by various groups on nearly 350 points of POGK with the use of LaCoste&Romberg (LCR) gravimeters were linked to those 12 stations. The construction of the network, in particular the limited number of non homogeneously distributed absolute gravity stations with gravity determined with different instruments in different epochs is responsible for systematic errors in g on POGK stations. The estimate of those errors with the use of gravity measurements performed in 2007-2008 is given and their possible sources are discussed. The development of absolute gravity measurement technologies, in particular instruments for precise field absolute gravity measurements, provides an opportunity to establish new type of gravity control consisting of stations surveyed with absolute gravimeters. New gravity control planned to be established in 2012-2014 will consist of 28 fundamental points (surveyed with the FG5 - gravimeter), and 169 base points (surveyed with the A10 gravimeter). It will fulfill recent requirements of geodesy and geodynamics and it will provide good link to the existing POGK. A number of stations of the new gravity control with precisely determined position and height will form the national combined geodetic network. Methodology and measurement schemes for both absolute gravimeters as well as the technology for vertical gravity gradient determinations in the new gravity control were developed and tested. The way to assure proper gravity reference level with relation to ICAG and ECAG campaigns as well as local absolute gravimeter comparisons are described highlighting the role of metrology in the project. Integral part of the project are proposals of re-computation of old gravity data and their transformation to a new system (as 2nd order network) as well as a definition of gravity system as “zero-tide” system. Seasonal variability of gravity has been discussed indicating that the effects of environmental changes when establishing modern gravity control with absolute gravity survey cannot be totally neglected.
Założona w Polsce w ostatniej dekadzie XX wieku zgodnie z obowiązującymi standardami międzynarodowymi Podstawowa Osnowa Grawimetryczna Kraju (POGK), składająca się z około 350 punktów, została oparta na 12 absolutnych punktach grawimetrycznych, na których przyspieszenie siły ciężkości wyznaczono przy użyciu czterech różnych typów grawimetrów absolutnych. Względne pomiary grawimetryczne na punktach tej osnowy, z jednoczesnym dowiązaniem jej do przyspieszenia siły ciężkości na 12 absolutnych punktach grawimetrycznych, wykonały różne grupy pomiarowe przy wykorzystaniu grawimetrów LaCoste&Romberg (LCR). Konstrukcja powstałej sieci grawimetrycznej, w szczególności ograniczona liczba nierównomiernie rozłożonych punktów absolutnych na terenie kraju, na których w dodatku przyspieszenie siły ciężkości wyznaczono różnymi instrumentami w różnych epokach, spowodowały wystąpienie błędów systematycznych w wartościach g na punktach POGK. W niniejszej pracy, przy wykorzystaniu pomiarów grawimetrycznych wykonanych w latach 2007-2008 dokonano oceny tych błędów oraz przeprowadzono dyskusję ich możliwych źródeł. Rozwój technologii absolutnych pomiarów grawimetrycznych, w szczególności instrumentów przeznaczonych do precyzyjnych absolutnych pomiarów grawimetrycznych w warunkach polowych, stwarza możliwość założenia nowego typu osnowy grawimetrycznej, składającej się ze stacji, na których przyspieszenie siły ciężkości jest pomierzone grawimetrami absolutnymi. Nowa osnowa grawimetryczna Polski, która będzie zakładana w latach 2012-2014, będzie się składała z 28 punktów fundamentalnych (mierzonych grawimetrem FG5) i 169 punktów bazowych (mierzonych grawimetrem A10). Będzie ona spełniała wymagania współczesnej geodezji i geodynamiki oraz zapewniała dobre powiązanie z istniejącą osnową POGK. Znaczna liczba punktów nowej osnowy grawimetrycznej, o precyzyjnie wyznaczonej pozycji wysokości utworzy krajową zintegrowaną osnowę geodezyjną. Opracowano i przetestowano metodologie i procedury pomiarowe na punktach nowej osnowy grawimetrycznej dla obu grawimetrów absolutnych (FG5, A10) oraz technologie wyznaczania gradientu pionowego przyspieszenia siły ciężkości na tych punktach. Określono metody zapewnienia odpowiedniego poziomu grawimetrycznego osnowy poprzez udział grawimetrów FG5 i A10 w międzynarodowej (ICAG) i europejskiej (ECAG), a także lokalnych kampaniach porównawczych grawimetrów absolutnych podkreślając jednocześnie rolę metrologii w projekcie. Integralnymi częściami projektu są zamierzenia przeliczenia archiwalnych danych grawimetrycznych wykorzystywanych przy tworzeniu POGK i ich przetransformowania do nowego systemu (jako sieć 2 rzędu) oraz zdefiniowania nowego systemu grawimetrycznego jako systemu „zero-tide”. Przeprowadzono również dyskusję zmienności sezonowej przyspieszenia siły ciężkości wskazując, że przy wyznaczaniu przyspieszenia siły ciężkości na punktach nowoczesnej osnowy grawimetrycznej wpływ zmian środowiskowych nie może być traktowany jako w pełni zaniedbywalny.
Źródło:
Geodesy and Cartography; 2013, 62, 1; 3-21
2080-6736
2300-2581
Pojawia się w:
Geodesy and Cartography
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A comparison between cylindrical and cross-shaped magnetic vibration isolators: ideal and practical
Autorzy:
Van Casteren, D.T.E.H.
Paulides, J.J.H.
Lomonova, E.A.
Powiązania:
https://bibliotekanauki.pl/articles/140574.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
gravity compensation
magnetic
vibration isolation
Opis:
In this paper a cross-shaped isolator consisting of cuboidal magnets and a cylindrical isolator are compared by resonance frequency to volume ratio and shape. Both isolators are capable of obtaining a low resonance frequency, i.e. 0.15 Hz and 0.01 Hz for the cross and cylinder, respectively. The volume of both isolators is comparable, only the shape is different, resulting in a tall structure with a small footprint for the cross and a flat with a large diameter cylindrical structure. A sensitivity analysis shows that due to the large amount of magnets, the cross-shaped isolator is less sensitive to manufacturing tolerances.
Źródło:
Archives of Electrical Engineering; 2015, 64, 4; 593-604
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Control and correction of horse riders body posture
Autorzy:
Mrozkowiak, Mirosław
Ambroży, Dorota
Powiązania:
https://bibliotekanauki.pl/articles/1055190.pdf
Data publikacji:
2014
Wydawca:
Uniwersytet Szczeciński. Wydawnictwo Naukowe Uniwersytetu Szczecińskiego
Tematy:
balance
centre of gravity
feedback
stability
Opis:
Centre of gravity represents the point where the net force of gravity of all the body parts is applied. Balance is a specific state of the postural control system, being a vertical orientation of human body maintained through balancing the forces and moments of forces that act on the body. Stability is understood to mean the ability to recover the state of balance and typical body position in the space. The concept of division of the rider's posture into 5 blocks that has been used in the literature seems to be legitimate. However, due to the natural shape of spinal curvature, the division of body into opposing truncated pyramids (a trapezoid in the sagittal plane and a rectangle with longer horizontal sides in the frontal plane) appears to be more accurate. The eight-segment model is dynamic and illustrates all the shallowed or deepened spinal curvatures very well while maintaining alternate sagittal curvatures with regard to the deficits of motion in the joints. It is also correct in anatomical terms since it contains all the sections and joints in the kinematic chain. Body posture, considered under conditions of the equestrian pair (a rider and a horse) as a motor task, will be adjusted using the continuous control. This control works within the tracking system and consistently adjusts the activity of different muscles to current needs. These needs result from a specific program encoded in the central nervous system and, more specifically, from the difference between the program and current state of the equestrian pair. This program is developed during equestrian training and it represents a demanded situation.
Źródło:
Central European Journal of Sport Sciences and Medicine; 2014, 6, 2; 21-33
2300-9705
2353-2807
Pojawia się w:
Central European Journal of Sport Sciences and Medicine
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Gravity Unfolding Analysis for Asymmetric Similarities Matrix
Grawitacyjna analiza unfolding dla niesymetrycznej macierzy podobieństw
Autorzy:
Zaborski, Artur
Powiązania:
https://bibliotekanauki.pl/articles/904580.pdf
Data publikacji:
2013
Wydawca:
Uniwersytet Łódzki. Wydawnictwo Uniwersytetu Łódzkiego
Tematy:
unfolding analysis
gravity model
preference maps
Opis:
The multidimensional unfolding analysis which uses in the structure the gravity function allows consideration and analysis of additional factors (such as market share or brand loyalty), which affect the assessments of respondents preference scores. In classical unfolding models these factors are ignored or assumed to be the same for all objects. The gravity unfolding analysis can also be used for graphical presentation of the data contained in the asymmetric similarity matrix expressing information about changes in respondents’ preferences in a definite period. As a result, instead of the configuration of points representing objects and respondents, the configuration of points representing objects at different periods is obtained.
Wielowymiarowa analiza unfolding wykorzystująca w swojej konstrukcji funkcję grawitacji pozwala na uwzględnienie w analizie dodatkowych czynników (takich jak udział w rynku lub lojalność względem marki), które mają wpływ na oceny preferencji respondentów. W klasycznej analizie unfolding udział ten jest ignorowany lub przyjmuje się, że jest on taki sam dla wszystkich obiektów. Grawitacyjna analiza unfolding może być również wykorzystana do graficznej prezentacji danych zawartych w niesymetrycznej macierzy podobieństw. Macierz taka zawiera informacje na temat zmian preferencji respondentów w pewnym okresie. W rezultacie nie otrzymujemy na mapie percepcyjnej, tak jak w przypadku analizy unfolding, konfiguracji punktów i respondentów, ale konfigurację punktów reprezentujących obiekty w różnych okresach.
Źródło:
Acta Universitatis Lodziensis. Folia Oeconomica; 2013, 286
0208-6018
2353-7663
Pojawia się w:
Acta Universitatis Lodziensis. Folia Oeconomica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modelling of gravity waves in water of finite depth
Autorzy:
Chybicki, W.
Powiązania:
https://bibliotekanauki.pl/articles/241311.pdf
Data publikacji:
2004
Wydawca:
Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN
Tematy:
gravity waves
Hamilton principle
Lagrangian description
Opis:
An extension of shallow water theory proposed by Wilde (Wilde, Chybicki 2000), for finite water depth and based on the Lagrangian type formalism is presented. As in Bussinesq-type models the vertical dimension is being eliminated and the horizontal displacement is expanded in the even power series of vertical variable Y, but only two terms - with power null and two are taken into account. Based on continuity equation, vertical displacement is expressed in terms of horizontal displacement and its derivatives. The equations of motion are derived from a Hamilton principle applied to Lagrangian function being a difference of kinetic and potential energy. In order to solve the set of governing equations a direct method of variational calculus has been applied. The solutions preserve total energy. The numerical simulations have been verified experimentally, in terms of wave measurements in the flume, for various wave heights and ratios of wavelength to water depth, showing good conformity between measured and calculated values. The theory presented here can also be applied for the case of varying depth.
Źródło:
Archives of Hydro-Engineering and Environmental Mechanics; 2004, 51, 3; 205-224
1231-3726
Pojawia się w:
Archives of Hydro-Engineering and Environmental Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Determinants of inward FDI into Visegrad countries: empirical evidence based on panel data for the years 2000–2012
Autorzy:
Wach, Krzysztof
Wojciechowski, Liwiusz
Powiązania:
https://bibliotekanauki.pl/articles/557695.pdf
Data publikacji:
2016-03-30
Wydawca:
Uniwersytet Ekonomiczny w Poznaniu
Tematy:
FDI, V4 countries, gravity model
Opis:
The purpose of this article is to explain which factors are important determinants for allocating FDI in the Visegrad Group countries (the Czech Republic, Hungary, Poland, Slovakia) by investors from the “old” EU member states. The article is divided into three main sections, except for the introduction and the final conclusions. First, we discuss the literature on the determinants of FDI. In Section 2 we introduce the applied research methodology. Finally in (Section 3), we present and discuss the empirical results. We selected 13 variables which were used in the estimation of the panel models, they include core gravity model variables such as the economy size (home and host nominal GDP per capita), geographical distance as well as augmented gravity model variables such as access to the sea and/or a common border. We also selected five efficiency-seeking variables (labour productivity, unemployment rate, minimum wage, corporate tax rate, investor protection index) as well as two membership variables (EU, EMU). Adding such variables as “common V4 border”, “EMU membership” or “protection index” seems to offer a novel approach. FDI from EU-15 countries are allocated in V4 countries more because of the home and host market potential measured by GDP so they can be classified as pure mark-seeking horizontal FDI. Currently investors from the mature EU-15 countries, whilst allocating FDI in V4 countries rather do not seek efficiency (as before), but the short distance is more important for them (than it used to be before the accession).
Źródło:
Economics and Business Review; 2016, 2(16), 1; 34-52
2392-1641
Pojawia się w:
Economics and Business Review
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ekonomiczne uwarunkowania migracji międzywojewódzkich w Polsce
Economic Factors Behind Interregional Migration in Poland
Autorzy:
Roszkowska, Sylwia
Powiązania:
https://bibliotekanauki.pl/articles/575754.pdf
Data publikacji:
2009-04-30
Wydawca:
Szkoła Główna Handlowa w Warszawie. Kolegium Analiz Ekonomicznych
Tematy:
migration
gravity model
regional inequalities
development
Opis:
The article examines the economic determinants of interregional migrations in Poland in 1995-2006. The author describes selected theoretical issues linked with the process and analyzes the influence of economic factors on interregional migration flows. Roszkowska evaluates the influence of selected macroeconomic variables on interregional migration flows using gravity models and data such as GDP per capita, labor productivity, unemployment, and the level of urbanization in individual provinces in Poland in 1995-2006. The analysis enabled the author to identify the most popular destinations for migration. These are chiefly provinces with a relatively well-developed infrastructure, a modern labor force structure by sector, and high economic development indicators. Outlying and poor provinces are the least popular destinations as far as migration is concerned, Roszkowska says. She concludes that the economic development of individual provinces-measured with indicators such as GDP per capita, the situation on regional labor markets, including differences in pay and unemployment rates, and the size of urban centers-has a statistically significant impact on interregional migration flows in Poland.
Źródło:
Gospodarka Narodowa. The Polish Journal of Economics; 2009, 231, 4; 55-74
2300-5238
Pojawia się w:
Gospodarka Narodowa. The Polish Journal of Economics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Bilateral Trade and Strategic Rivalry
Autorzy:
Dishkant, Ksenia
Powiązania:
https://bibliotekanauki.pl/articles/2232486.pdf
Data publikacji:
2023-07-17
Wydawca:
Academicus. International Scientific Journal publishing house
Tematy:
cost of conflict
rivalry
gravity model
Opis:
Conflict is a costly endeavor. However, conflict itself is of unobservable magnitude which makes statistical inference problematic. The long-run economic cost of conflict is calculated as the sum of the contemporaneous costs and the discounted value of future costs. Typically, researchers use War or Militarized Interstate Conflicts as independent, discrete events to calculate its contemporaneous effect and then introduce a time binary variable to estimate the lagged effects since the end of the event. The conflict datasets accurately recognize the dates of the core conflict. However, they ignore the possibility that a lack of militarized conflict does not necessarily mean that issues have been settled, thus we are underestimating overall costs. The present study estimates the economic costs of rivalry. The international rivalry cycle is a process in which a pair of states create and sustain a relationship of atypical hostility for some period. This paper is part of the renaissance of research activity in the applied economics of international trade. The gravity model is used to determine the economic cost of Rivalry on bilateral trade using panel data. At the aggregate level, strategic and enduring rivalries have a negative and significant effect on trade flow. The results show that the total effect of rivalry accounts for48%-57% of the fall in bilateral trade volume, which is equivalent in cost to 19% of the ad-valorem tax. If the rivalry is disaggregated by claim type: spatial, positional, and mixed, then we observe that the cost varies substantially with the type. Spatial rivalry explains 16%-26% of the fall in trade volume, while positional and mixed rivalry explain 49%-57% and 77%-82%, respectively.
Źródło:
Academicus International Scientific Journal; 2023, 14, 28; 142-168
2079-3715
2309-1088
Pojawia się w:
Academicus International Scientific Journal
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Research on gravity field modelling and gravimetry in Poland in 2015–2018
Autorzy:
Krynski, Jan
Dykowski, Przemysław
Olszak, Tomasz
Powiązania:
https://bibliotekanauki.pl/articles/145412.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
pole grawitacyjne
grawimetria
geoida
gravity field
gravimetry
global geopotential model
geoid
absolute gravity measurements
Opis:
Activities of the Polish research gSDroups concerning gravity field modelling and gravimetry in a period of 2015–2018 are reviewed and summarised in this paper. The summary contains the results of research on the evaluation of GOCE-based global geopotential models (GGMs) in Poland and geoid modelling. Extensive research activities are observed in the field of absolute gravity surveys, in particular for the maintenance of national gravity control in Poland, Sweden, Denmark, the Republic of Ireland and in Northern Ireland as well as for geodynamics with special emphasis on metrological aspects in absolute gravimetry. Long term gravity variations were monitored in two gravimetric laboratories: the Borowa Gora Geodetic-Geophysical Observatory, and Jozefoslaw Astrogeodetic Observatory with the use of quasi-regular absolute gravity measurements as well as tidal gravimeter records. Gravity series obtained were analysed considering both local and global hydrology effects. Temporal variations of the gravity field were investigated using data from GRACE satellite mission as well as SLR data. Estimated variations of physical heights indicato the need for kinematic realization of reference surface for heights. Also seasonal variability of the atmospheric and water budgets in Poland was a subject of investigation in terms of total water storage using the GLDAS data. The use of repeatable absolute gravity data for calibration/validation of temporal mass variations derived from satellite gravity missions was discussed. Contribution of gravimetric records to seismic studies was investigated. The bibliography of the related works is given in references.
Źródło:
Geodesy and Cartography; 2019, 68, 1; 31-63
2080-6736
2300-2581
Pojawia się w:
Geodesy and Cartography
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Vertical gravity gradient determination for the needs of contemporary absolute gravity measurements - first results
Autorzy:
Dykowski, P.
Powiązania:
https://bibliotekanauki.pl/articles/224809.pdf
Data publikacji:
2012
Wydawca:
Politechnika Warszawska. Wydział Geodezji i Kartografii
Tematy:
absolute gravity determination
free-fall gravimeter
vertical gravity gradient
pionowy gradient grawitacji
pomiary ciężkości
Opis:
Current development of gravimetric measurement technologies gives an opportunity to determine absolute gravity value with high precision, also in field conditions. In particular, it concerns gravity determination with the use of the A 10 free-fall gravimeter manufactured by Micro-g Solutions. Surveys with the A 10 as well as with FG5 gravimeters require precise determination of vertical gravity gradient in order to properly reduce the measured gravity value, e.g. to the benchmark level. A special stand of multiple levels (20 cm interval) for vertical gradient determination had been designed and constructed in the Institute of Geodesy and Cartography (IGiK), Warsaw. The stand enables the determination of the vertical gravity gradient on every station where the measurement with the A10 can be performed. First results of vertical gradient determinations at the Polish National Gravity Control points in Borowa Gora Geodetic-Geophysical Observatory (two laboratory and one field station) with the use of the stand developed are presented in the paper. Results of measurements on multiple levels were fitted with linear and nonlinear model and compared with vertical gravity gradients determined in the year 2000, based on the measurements using a standard tripod. Measurement methodology with the use of the stand has been proposed.
Źródło:
Reports on Geodesy; 2012, z. 1/92; 23-36
0867-3179
Pojawia się w:
Reports on Geodesy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Research on gravity field modelling and gravimetry in Poland in 2019–2022
Autorzy:
Krynski, Jan
Dykowski, Przemysław
Godah, Walyeldeen
Szelachowska, Małgorzata
Powiązania:
https://bibliotekanauki.pl/articles/43852764.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
geoida
pole grawitacyjne
grawimetria
geoid
gravity field
absolute gravity measurements
gravimetry
GRACE/GRACE-FO satellite missions
Opis:
The article presents the reviewed and summarised research activities of the Polish research groups on gravimetry and gravity field modelling in the period of 2019–2022. It contains the results of absolute gravity surveys for the maintenance of the international gravity reference level in Poland and Europe, and for geodynamic research with an emphasis on metrological aspects. It also contains relative gravimetry issues as well as the results of marine gravity surveys in the southern Baltic Sea. Non-tidal gravity changes were extensively investigated. Long-term gravity variations were monitored at the Borowa Gora Geodetic-Geophysical Observatory and in a few other locations in Poland. The contribution of gravimetric records to seismic studies was investigated. Temporal variations of the gravity field from GRACE (Gravity Recovery and Climate Experiment) and GRACE-FO (GRACE Follow-On) data, in particular, deformations of the Earth’s surface as well as temporal variations of heights, total water storage and groundwater storage were investigated. Moreover, GRACE-based products and the performance of monthly Global Geopotential Models (GGMs) were a subject of research. GGMs developed in last years were evaluated. The research on developing new approaches in geoid modelling and their validation was conducted. New regional and local geoid models were determined for Poland and Ethiopia. The use of different techniques for estimating the absolute sea level at sites of the selected network in the Baltic Sea was investigated.
Źródło:
Advances in Geodesy and Geoinformation; 2023, 72, 2; art. no. e46, 2023
2720-7242
Pojawia się w:
Advances in Geodesy and Geoinformation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Grawimetryczne badania dynamiki rejonu wysadu solnego "Dębina"
Gravity research on dynamics of the area salt dome "Dębina"
Autorzy:
Łój, M.
Powiązania:
https://bibliotekanauki.pl/articles/349406.pdf
Data publikacji:
2008
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
badania grawimetryczne
czasowe zmiany sił ciężkości
współczesne procesy geodynamiczne
gravity measurement
contemporary geodynamic process
temporal gravity changes
Opis:
Praca przedstawia wyniki pięcioletnich badań grawimetrycznych na terenie wysadu solnego "Dębina". Wysad ten oddziela pola eksploatacyjne Kopalni Węgla Brunatnego Bełchatów i jest narażony na działania związane z ingerencją człowieka w górotwór - takie jak postępujące odwodnienie czy zmiana nacisku na boczne ściany wysadu. Celem przeprowadzonych tam badań grawimetrycznych było stwierdzenie, czy w czasowych zmianach pola sił ciężkości zaznaczać się będą dynamiczne zmiany zachodzące na i wokół wysadu, a także próba znalezienia źródeł pojawiających się zmian czasowych.
This paper presents results from two geodynamic profiles; located of the "Dębina" salt dome in Bełchatów. "Dębina salt dome separates Bełchatów deposit from Szczerców deposit. Currently, the exploitation on the Bełchatów field approaches the slat dome limits and at the same time the construction of the new Szczerców strip mine has been started, which influences the dynamics of the phenomena occurring in the salt dome. The idea behind this research project is to attempt to quantitatively interpret the results received from the gravimetric investigations i.e. to link temporal gravity changes with processes on "Dębina" salt dome.
Źródło:
Górnictwo i Geoinżynieria; 2008, 32, 1; 169-179
1732-6702
Pojawia się w:
Górnictwo i Geoinżynieria
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Gravimeter with two-dimension digital processing of measuring information
Autorzy:
Bezvesilnaya, E.
Podchashinsky, Y.
Korobyjchuk, I.
Powiązania:
https://bibliotekanauki.pl/articles/387031.pdf
Data publikacji:
2009
Wydawca:
Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej
Tematy:
przetwarzanie danych
grawitacja
data processing
gravity
Opis:
Gravimeter with two-dimensional digital data processing about acceleration of gravity is considered in a paper. The result of measurements in gyroscopic gravimeter contains errors. An influence on gravimeter inertial absolute acceleration and other disturbing influences cause the errors of measurements. These of acceleration arise by work gravimeter onboard the plane in structure of air gravimetric system. The structural scheme of gyroscopic gravimeter is proposed in a paper for multiple precision. This construction is providing immediate measurements of acceleration of gravity. The possibility of digital data processing is considered in view of a two-dimensional character of an array of measuring information.
Źródło:
Acta Mechanica et Automatica; 2009, 3, 4; 8-12
1898-4088
2300-5319
Pojawia się w:
Acta Mechanica et Automatica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Detection of ferromagnetic objects in local magnetic anomaly of the Baaltic Sea
Autorzy:
Wołoszyn, M.
Powiązania:
https://bibliotekanauki.pl/articles/258930.pdf
Data publikacji:
2008
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
geological researches
gravity
electromagnetic
magnetic methods
Opis:
In geological researches several kinds of methods are applied to discovering the natural resources. Planes, helicopters and UAVs (UnmAnned Vehicle) are used in researches in large areas. The gravity, electromagnetic and magnetic methods, which are used in geological researches, are presented in this paper. The special attention was paid to magnetic systems installed on mobile platforms. The magnetic field of the Earth obtained from mathematical model was compared to the real magnetic field in the selected part of the Baltic Sea. The results of the calculations showed that the mathematical model of the Earth’s magnetic field does not consider local magnetic anomalies. The strong local magnetic anomalies cause serious problems with detection of underwater objects. Special problems appear in the magnetic system on a helicopter, which are presented in this paper.
Źródło:
Polish Maritime Research; 2008, 2; 77-82
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-25 z 324

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