Wyniki wyszukiwania - BazTech

1

Simulating Filtration to Evaluate Hydrodynamic Indices of the Underground Gas Storage Operation

Sadovenko Іvan, Inkin Оlexander, Dereviahina Nataliia

Inżynieria Mineralna

|

2023

|

no. 1

97--102

EN

The research objective is to develop and test mathematical model of gas storage in the layered aquifer with poorly permeable interlayer if plane-parallel and axisymmetric filtration takes place. The paper evaluates the gas-hydrodynamic operational indices of the underground gas storages within aquifers in the South East Ukraine. Comprehensive approach has been applied involving collection, systematization, and analysis of actual data on filtration and physicomechanical properties of enclosing rocks impacting formation of natural and technogenic deposits as well as analytical and numerical methods to solve equations of the gas-water contact shift under different conditions. A gas-hydrodynamic model of underground gas storage within the nonuniform aquifer has been substantiated to calculate its cyclic operation in the three-layered seam taking into consideration crossflows through a poorly permeable stopping. The calculation results show significant impact of characteristics of the layered porous environment on the gas water contact transfer through certain seams. The derived new technique linearizing a system of differential equations to identify pressure within a reservoir is generalization of the earlier applied procedures with introduction of ‘boundary schemes’. The calculation results demonstrate significant impact of the layered porous environment on the gas water contact transfer through certain seams. The findings may be applied while making evaluations at the stage of gas storage design within aquifers.

PL

Celem badań jest opracowanie i przetestowanie modelu matematycznego magazynowania gazu w warstwie wodonośnej ze słabo przepuszczalną międzywarstwą, przy założeniu filtracji płasko-rownóległej i osiowo-symetrycznej. W artykule dokonano oceny gazowo-hydrodynamicznych wskaźników eksploatacyjnych podziemnych magazynów gazu w warstwach wodonośnych południowo- wschodniej Ukrainy. Zastosowano kompleksowe podejście polegające na zebraniu, usystematyzowaniu i analizie rzeczywistych danych, dotyczących właściwości filtracyjnych i fizykomechanicznych skał otaczających, wpływających na powstawanie osadów naturalnych i technogenicznych, a także analityczne i numeryczne metody rozwiązywania równań przesunięcia kontaktu gaz-woda w rożnych warunkach. Model gazowo-hydrodynamiczny podziemnego magazynowania gazu w niejednorodnej warstwie wodonośnej został uzasadniony w celu obliczenia jego cyklicznej pracy w pokładzie trójwarstwowym z uwzględnieniem przepływów krzyżowych przez słabo przepuszczalną zaporę. Wyniki obliczeń wskazują na istotny wpływ charakterystyk warstwowego środowiska porowatego na kontakt gazu z wodą przez określone pokłady. Nową techniką linearyzującą układ równań różniczkowych do identyfikacji ciśnienia w zbiorniku jest uogólnienie wcześniej stosowanych procedur poprzez wprowadzenie „schematów brzegowych”. Wyniki obliczeń wskazują na istotny wpływ warstwowego środowiska porowatego na kontakt gazu z wodą przez określone pokłady. Uzyskane wyniki mogą być wykorzystane przy dokonywaniu ocen na etapie projektowania magazynów gazu w warstwach wodonośnych.

2

Temporal and spatial heterogeneity of the Ailaoshan–Song Ma–Song Chay ophiolitic mélange, and its significance on the evolution of Paleo-Tethys

Lin Wei, Liu Fei, Wang Ying, Meng Lingtong, Faure Michel, Chu Yang, Nguyen Vuong Van, Wu Qinying, We Wei, Thu Hoai Luong Thi, Vu Tich Van

Geotourism / Geoturystyka

|

2023

|

nr 1-2 (72-73)

42--43

EN

The ophiolite is the direct evidence to restore the oceanic evolution, and it is used to identify the convergence boundary of the plates. Compared with ophiolite, ophiolitic mélange, especially its matrix, contains more information about the evolution of ocean. The evolution of eastern Paleo-Tethys, between the South China and Indochina blocks, recorded the whole process of rifting from Gondwana and their northward migration and convergence. To understand the tectonic implications from matrix of ophiolitic mélange, the Mesozoic Paleo-Tethys Ailaoshan–Song Ma–Song Chay suture zone located in the North Vietnam–Southeast Yunnan region acts as an ideal study area. Based on the structural geology, we reviewed previous zircon U-Pb dating and Lu-Hf isotopic analyses on the detrital zircon from the Ailaoshan–Song Ma–Song Chay ophiolitic mélange. Accordingly, we subdivide the matrix of these ophiolitic mélange into four parts (M1, M2, M3, and M4; Fig. 1). M1 is mainly located in the middle segment of the Ailaoshan–Song Ma belt. It shows age peaks of 440 Ma and 960 Ma with εHf(t) values of −19.6 ~ +10.3. M2 is mainly located in the NW segment of the Ailaoshan–Song Ma belt, showing a dominant age peak of ~260 Ma. Particularly, it has εHf(t) values of −28.9 ~ +8.1. M3 is mainly located in the SE segment of the Ailaoshan–Song Ma belt, showing the peaks at ~250 Ma, 440 Ma, and 960 Ma with εHf(t) values of −21.9 ~ +10.1. M4 is mainly located in the Song Chay belt, showing the peaks at ~310 Ma, 470 Ma, 610 Ma, 770 Ma, and 965 Ma with εHf(t) values of −28.2 ~ +10.8. The geochronological data of the detrital zircon from the matrix of the Ailaoshan– Song Ma–Song Chay ophiolitic mélange zone, documents a temporal heterogeneity between the M1, M2, M3, and M4 units, which formed at 310–270 Ma, 265–250 Ma, 245–240 Ma, and 310–255 Ma, respectively. The different components and provenances of each unit reflect a strike-parallel heterogeneity (Fig. 1). The M1 unit was mainly sourced from the Paleozoic sedimentary rocks of the Indochina Block (IB). The main provenance for the M2 unit is Emeishan Large Igneous Province (ELIP). The magmatic arc developed in the IB provided the materials for the M3 unit, and the detrital materials of the M4 were mainly sourced from the South China Block (SCB) (Fig. 1). The Cenozoic strike-slip deformation led to an inverted geometry of the M1, M2, and M3 units, accounting for a strike-perpendicular heterogeneity straight to the strike of the orogenic belt. The temporal, strike-parallel, and strike-perpendicular heterogeneity help us to decipher the tempo-spatial evolution of the Paleo-Tethys. The M1, M2, M3, and M4 units contain information from different evolutionary stages, likely recording the comprehensive history of the ancient oceanic basin. Importantly, our results demonstrate that both the active continental margin of the IB and the passive continental margin of the SCB acted as provenance sources that supplied significant amount of detrital material in the ophiolitic mélange matrix, indicating that the Paleo-Tethys Ocean was a “narrow” or “limited” ocean rather than the archipelagic ocean proposed before.

3

Maximum simulated likelihood: don't stop believin'?

Schrey Christopher

Annals of Computer Science and Information Systems

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2021

|

Vol. 26

175--180

EN

Unobserved heterogeneity may complicate model estimation in econometrics. To integrate out the effect of unobserved heterogeneity via maximum simulated likelihood (MSL) estimation, assumptions regarding the underlying distribution need to be made. Researchers seldomly discuss these assumptions. This raises the question, to what extent estimation results in the MSL-context are robust to potential distributional mismatch. This work-in-progress derives the research question from the literature. A simulation study is conducted that underpins the relevance of this matter, where results imply that mismatch may introduce significant bias. Intended future work to properly address and answer this question is defined and discussed.

4

Increasing the reusability of IoT-aware business processes

Wehlitz Robert, Jauer Florian, Rößner Ingo, Franczyk Bogdan

Annals of Computer Science and Information Systems

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2020

|

Vol. 22

17--22

EN

The Internet of Things (IoT) is based on connected devices which are often heterogeneous in terms of supported communication protocols, interfaces and message formats. IoT-aware business processes, which are executed by process engines, are often bound to specific device types. This decreases their reusability when they are ought to be deployed in multiple IoT scenarios where the ability of supporting different device types is an important requirement. In this paper, we introduce a novel approach on how to overcome the heterogeneity of IoT devices, thus increasing the reusability of IoT-aware business processes. The contribution of this work to information systems research is twofold: First, we present a device abstraction model as the basis to define business process tasks across heterogeneous device types without the need of dealing with their technical implementations. Secondly, we propose a system architecture which supports the modeling, deployment, execution and reuse of IoT-aware business processes.

5

Niejednorodność i wady materiałowe opon samochodów osobowych - zagadnienia wybrane

Bęczkowska S., Korzeb J., Koziak S., Opala M., Weyssenhoff A.

Prace Naukowe Politechniki Warszawskiej. Transport

|

2018

|

z. 121

9--20

PL

W artykule dokonano analizy wybranych wad materiałowych i skutków jakie mogą powstawać w wyniku użytkowania wadliwych opon do samochodów osobowych. Omówiono także konstrukcję opony i materiały użyte w trakcie jej produkcji. W artykule Autorzy przedstawili metody badań i dopuszczalne parametry z pomiarów niejednorodności materiałowej opon.

EN

The article analyses the selected defects and consequences which may result from the use of defective tires for passenger cars. It also describes the assembly of the tires and the materials used in its production. In the article the authors presented their research methods and acceptable parameters of the measurements of non-uniformity of materials.

6

A study on vibration of tapered non-homogeneous rectangular plate with structural parameters

Kaur N., Singhal A., Khanna A.

International Journal of Applied Mechanics and Engineering

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2018

|

Vol. 23, no. 4

873--884

EN

Effects of structural parameters on the vibration of a tapered non-homogeneous rectangular plate with different combinations of boundary conditions are discussed. Tapering in the plate is assumed to be sinusoidal in the x-direction. Here, temperature variation and non-homogeneity in the plate material are also considered sinusoidal in the x-direction. The Rayleigh-Ritz method is used to calculate the frequency parameter for the first two modes of vibration for different values of the structural parameters, i.e. the taper parameter, thermal gradient, aspect ratio and non-homogeneity constant. Results are obtained for three boundary conditions, i.e. clamped boundary (C-C-C-C), simply supported boundary (SS-SS-SS-SS) and clamped-simply supported boundary (CSS-C-SS). Numerical values of the frequency parameter are given in a compact tabular form.

7

Impact of pre-stress, inhomogeneity and porosity on the propagation of Love wave

Gupta S., Pramanik A., Ahmed M.

Acta Geophysica

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2018

|

Vol. 66, no. 5

855--866

EN

This work presents a mathematical modelling of Love wave transference through a pre-stress influenced anisotropic medium with heterogeneity between a sandy medium and an initially stressed anisotropic porous medium. Variable separation method has been induced in order to derive the frequency relation. Using appropriate boundary conditions at two interfaces, the dispersion equation has been obtained in its closed form. Possible particular cases are considered, and the corresponding results are consonant with the classical cases. Numerical computations have been employed to demonstrate the role of inhomogeneity factors, initial stresses and porosity, and are depicted by means of graphs which substantiates that those parameters immensely affect the Love wave velocity. In mineral prospecting and exploring technique in earth, the method and the results of this problem may be applicable.

8

Impact of Inhomogeneity on SH-type Wave Propagation in an Initially Stressed Composite Structure

Saha S., Chattopadhyay A., Singh A. K.

Acta Geophysica

|

2018

|

Vol. 66, no. 1

1--19

EN

The present analysis has been made on the influence of distinct form of inhomogeneity in a composite structure comprised of double superficial layers lying over a half-space, on the phase velocity of SH-type wave propagating through it. Propagation of SH-type wave in the said structure has been examined in four distinct cases of inhomogeneity viz. when inhomogeneity in double superficial layer is due to exponential variation in density only (Case I); when inhomogeneity in double superficial layers is due to exponential variation in rigidity only (Case II); when inhomogeneity in double superficial layer is due to exponential variation in rigidity, density and initial stress (Case III) and when inhomogeneity in double superficial layer is due to linear variation in rigidity, density and initial stress (Case IV). Closed-form expression of dispersion relation has been accomplished for all four aforementioned cases through extensive application of Debye asymptotic analysis. Deduced dispersion relations for all the cases are found in well-agreement to the classical Love-wave equation. Numerical computation has been carried out to graphically demonstrate the effect of inhomogeneity parameters, initial stress parameters as well as width ratio associated with double superficial layers in the composite structure for each of the four aforesaid cases on dispersion curve. Meticulous examination of distinct cases of inhomogeneity and initial stress in context of considered problem has been carried out with detailed analysis in a comparative approach.

9

Wpływ niejednorodności struktury zginanych belek z drewna klejonego na efekt ich wzmocnienia

Wdowiak A., Kroner A.

Materiały Budowlane

|

2017

|

nr 1

87--89

PL

Artykuł opisuje doświadczalne badania pojedynczych modeli belek z drewna klejonego, pochodzących z Małopolskiej Krainy Przyrodniczo-Leśnej, wzmocnionych za pomocą taśm węglowych. Zastosowana tarcica konstrukcyjna została przesortowana wytrzymałościowo metodą wizualną zgodnie z PN-EN 14081-1:2016-03 [13]. Celem tych badań było sprawdzenie skuteczności wzmocnienia belek z drewna z defektami. Eksperymentalny program badawczy obejmował określenie nośności na zginanie niezbrojonych i zbrojonych belek klejonych, wykonanych z tarcicy sosnowej.

EN

This article describes the experimental laboratory testing of individual models of glued laminated timber beams derived from Little Poland Nature and Forest Land, strengthened with the use of carbon tapes. The endurance of used timber construction was graded visually according to PN-EN 14081-1:2016-03 [13]. The aim of this study was to verify the effectiveness of the strengthening defective timber beams. The experimental research programme included evaluation of capacity for bending of unreinforced and reinforced glued laminated timber beams, which were made of pine timber.

10

Analiza niejednorodnych struktur budowlanych w procesach naprawczo-rewaloryzacyjnych

Miedziałowski C., Walendziuk A.

Materiały Budowlane

|

2017

|

nr 11

20--21

PL

W artykule zaprezentowano propozycję sposobu modelowania i analizy struktur niejednorodnych w budownictwie. Model bazuje na metodzie elementów skończonych, znacznie redukując liczbę niewiadomych. Model może być zastosowany przy opracowaniu projektów wzmocnień, napraw i rewaloryzacji konstrukcji.

EN

The article presents a modelling and analysis method of non-homogeneous materials in building engineering. Proposed approach significantly reduces the number of unknowns in the finite element model. The model proposed can be used in strengthening design, repairs and revaluation of structures.

11

The effect of viscosity and heterogeneity on propagation of G-type waves

Gupta S., Smita

International Journal of Applied Mathematics and Computer Science

|

2017

|

Vol. 27, no. 2

253--260

EN

Earthquakes yield motions of massive rock layers accompanied by vibrations which travel in waves. This paper analyses the possibility of G-type wave propagation along the plane surface at the interface of two different media which is assumed to be heterogeneous and viscoelastic. The upper layer is considered to be viscoelastic and the lower half space is considered to be an initially stressed heterogeneous half space. The dispersion equation, as well as the phase and group velocities, is obtained in closed form. The dispersion equation agrees with the classical Love type wave. The effects of the nonhomogeneity of the parameters and the initial stress on the phase and group velocities are expressed by means of a graph.

12

Cylinder-to-cylinder and cycle-to-cycle variation in combustion process in radial aircraft engine

Gęca M.

Combustion Engines

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2017

|

R. 56, nr 1

77--83

EN

Cycle-to-cycle variation in combustion in a single cylinder of a radial engine has an impact on that in others and the entire engine. Steady- and transient-state engine operation was investigated, and the transient states were generated by cyclic changes in the timing of fuel injection to a given cylinder, having others operated on the same mixture composition. The measurement of pressure in the combustion chamber allowed for specifying indicated mean effective pressure (IMEP) in all cycles. The time series of IMEP were studied with mathematical techniques of non-linear dynamics, i.e. a wavelet transform and a multifractal analysis. Controlled disturbances in mixture composition in a single cylinder can have an impact on certain cylinders only. Cylinders 3, 5, 7 and 9 are most responsive to such disturbances, which proves their least cycle-to-cycle variation in combustion.

13

Magnetoelastic shear wave propagation in pre-stressed anisotropic media under gravity

Kumari N., Chattopadhyay A., Singh A. K., Sahu S. A.

Acta Geophysica

|

2017

|

Vol. 65, no. 1

189--205

EN

The present study investigates the propagation of shear wave (horizontally polarized) in two initially stressed heterogeneous anisotropic (magnetoelastic transversely isotropic) layers in the crust overlying a transversely isotropic gravitating semi-infinite medium. Heterogeneities in both the anisotropic layers are caused due to exponential variation (case-I) and linear variation (case-II) in the elastic constants with respect to the space variable pointing positively downwards. The dispersion relations have been established in closed form using Whittaker’s asymptotic expansion and were found to be in the well-agreement to the classical Love wave equations. The substantial effects of magnetoelastic coupling parameters, heterogeneity parameters, horizontal compressive initial stresses, Biot’s gravity parameter, and wave number on the phase velocity of shear waves have been computed and depicted by means of a graph. As a special case, dispersion equations have been deduced when the two layers and half-space are isotropic and homogeneous. The comparative study for both cases of heterogeneity of the layers has been performed and also depicted by means of graphical illustrations.

14

Effect of surface wave propagation in a four-layered oceanic crust model

Paul P., Kundu S., Mandal D.

Acta Geophysica

|

2017

|

Vol. 65, no. 6

1119--1131

EN

Dispersion of Rayleigh type surface wave propagation has been discussed in four-layered oceanic crust. It includes a sandy layer over a crystalline elastic half-space and over it there are two more layers—on the top inhomogeneous liquid layer and under it a liquid-saturated porous layer. Frequency equation is obtained in the form of determinant. The effects of the width of different layers as well as the inhomogeneity of liquid layer, sandiness of sandy layer on surface waves are depicted and shown graphically by considering all possible case of the particular model. Some special cases have been deduced, few special cases give the dispersion equation of Scholte wave and Stoneley wave, some of which have already been discussed elsewhere.

15

Badanie zmienności i niejednorodności zawartości popiołu i siarki w pokładzie 308 KWK Ziemowit

Paszek M., Auguścik J., Mucha J.

Zeszyty Naukowe Instytutu Gospodarki Surowcami Mineralnymi i Energią PAN

|

2016

|

nr 96

229--239

PL

Stosując metody statystyczne i geostatystyczne opisano liczbowo zmienność oraz zbadano niejednorodność zawartości popiołu oraz siarki w pokładzie 308 złoża KWK Ziemowit. Podstawę badań stanowiły wyniki analiz chemicznych prób bruzdowych pobranych w wyrobiskach górniczych. Analiza statystyczna obu parametrów wykazała ich dużą zmienność, znaczące odstępstwa rozkładów empirycznych od teoretycznego rozkładu normalnego i występowanie licznych wartości odstających. Zaproponowano dwa geostatystyczne modele zmienności parametrów: sferyczny dla zawartości popiołu oraz Gaussa dla zawartości siarki. W strukturze zmienności parametrów stwierdzono wyraźnie zaznaczony nielosowy charakter zmian ich wartości. Na podstawie map semiwariogramów kierunkowych (indykatrysy zmienności) ujawniono wyraźną anizotropię zmienności parametrów w zakresie odległości 1000–1500 m. Przy użyciu testu wielokrotnych porównań Gamesa-Howella wykazano niejednorodność rozmieszczenia badanych parametrów, mającą wpływ na ich dużą zmienność.

EN

The variability and heterogeneity of ash and sulphur contents in bituminous coal with seam no. 308 from the “Ziemowit” coal mine have been studied. The data stems from channel samples collected in mine works. The statistical analysis of both parameters showed big variability, significant deviations of empirical distributions from the theoretical normal distribution and occurrence of numerous outliers. Two geostatistical variability models were proposed: spherical for ash content and Gaussian for sulphur content. Anisotropy was revealed based on directional semivariogram maps. The heterogeneity of above-mentioned parameters was proven using a test of multiple comparisons (Games-Howell test).

16

Długookresowy monitoring obiektów posadowionych na podłożu ekspansywnym

Gadomska M.

Materiały Budowlane

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2015

|

nr 5

57--58

PL

Obiekty posadowione na podłożu ekspansywnym ulegają licznym uszkodzenion i wymagają długookresowych obserwacji. Na podstawie wieloletnich obserwacji stwierdzono istotne przemieszczenia pionowe, pomimo przeprowadzonych prac zabezpieczających. W przypadku niektórych obiektów przemieszczenia są zróżnicowane i w związku z tym można zrezygnować z częstych obserwacji części obiektu o nieznaczących przemieszczeniach.

EN

Objects constructed in expansive soil foundation reveal significant damage and require long-term observation. In effect of long-term monitoring, significant vertical displacements that had occurred despite conservation works, were found on the objects. On some objects the displacements are highly diversified and, therefore, observation of the parts with slight displacements can be abandoned.

17

Pollutant’s Horizontal Dispersion Along and Against Sinusoidally Varying Velocity from a Pulse Type Point Source

Singh M. K., Mahato N. K., Kumar N.

Acta Geophysica

|

2015

|

Vol. 63, no. 1

214--231

EN

An analytical solution of a two-dimensional advection diffusion equation with time dependent coefficients is obtained by using Laplace Integral Transformation Technique. The horizontal medium of solute transport is considered of semi-infinite extent along both the longitudinal and lateral directions. The input concentration is assumed at an intermediate position of the domain. It helps to evaluate concentration level along the flow as well as against the flow through one model only. The source of the input concentration is considered to be of pulse type. In the presence of the source, it is assumed to be decreasing very slowly with time, and just after the elimination of the source it is assumed to be zero. The dispersion coefficient and the advection parameter are considered directly proportional to each other. The analytical solution may be used to predict the solute concentration level with position and time in an open medium as well as in a porous medium. The effect of heterogeneity on the solute transport may also be predicted.

18

Niejednorodność masy szklanej - stare zło

Kuśnierz A., Marczewska A.

Świat Szkła

|

2014

|

R. 19, nr 4

39--41

19

Niejednorodność złóż w świetle badań geostatystycznych

Kokesz Z.

Przegląd Górniczy

|

2014

|

T. 70, nr 1

62--73

PL

W pracy scharakteryzowano zjawisko niejednorodności złóż polegające na obszarowym zróżnicowaniu średnich wartości parametrów złożowych oraz zróżnicowaniu struktury ich zmienności opisanej za pomocą semiwariogramów. Zwrócono w nim uwagę na niestabilność struktur zmienności parametrów złożowych. Stwierdzono, że obserwowane różnice w przebiegu semiwariogramów sporządzonych dla różnych części złoża rzadko są wywołane tzw. efektem proporcjonalności, a obszarowe zróżnicowanie struktury zmienności parametrów złożowych znajduje najczęściej wytłumaczenie w budowie geologicznej złóż. Wyniki badań sugerują, że małe fragmenty złóż mogą stanowić quasi-homogeniczne rejony. Badania wskazują na potrzebę głębszego analizowania struktur zmienności złóż i uwzględniania jej wyników przy prognozowaniu jakości kopaliny i szacowania zasobów metodą krigingu.

EN

The results of geostatistical studies of variability structures of the Polish mineral deposits have been presented. Special attention has been paid to the heterogeneity of variability structures of deposit parameters. It has been pointed that the variability of the parameters can be marked by different types of heterogeneity. It is interesting to note that non-homogeneity most frequently finds its explanation in deposit geology. It has been emphasized that the variability structures of the parameters should be analysed more deeply. When heterogeneity is evident it should be taken into account during determination of the quality of mineral raw materials and estimation of resources/reserves by kriging.

20

In-situ testing and heterogeneity of UFG Cu at elevated temperatures

Petrenec M., Král P., Dvořák J., Svoboda M., Sklenička V.

Journal of Achievements in Materials and Manufacturing Engineering

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2014

|

Vol. 62, nr 2

69--74

EN

Purpose: The motivation of present investigation is the study of deformation-induced processes during in-situ tensile and compression test at elevated temperature in order to elucidate the role of the microstructure changes during creep testing. Design/methodology/approach: Experiments were conducted to investigate deformation-induced processes during in-situ tensile test at elevated temperature. Findings: It was found that creep resistance of UFG pure Al and Cu is considerably improved after one ECAP pass in comparison with coarse grained material, however, further repetitive pressing leads to a noticeable deterioration in creep properties of ECAP material. Researches limitations/implications: In the present work was found that ultrafine-grained microstructure is instable and significant grain growth has already occurred during heating to the testing temperature. Originality/value: The experiments conducted on pure Al and Cu found that their creep resistance is considerably improved after one ECAP pass in comparison with unpressed material.