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Characterization of coal reservoirs and determination of in-situ physical coal properties related to transport mechanism are complicated due to having lack of standard procedures in the literature. By considering these difficulties, a new approach has been developed proposing the usage of relationships between coal rank and physical coal properties. In this study, effects of shrinkage and swelling (SS) on total methane recovery at CO2 breakthrough (TMRB), which includes ten-year primary methane recovery and succeeding enhanced coalbed methane (ECBM) recovery up to CO2 breakthrough, and CO2 sequestration have been investigated by using rank-dependent coal properties. In addition to coal rank, different coal reservoir types, molar compositions of injected fluid, and parameters within the extended Palmer & Mansoori (P&M) permeability model were considered. As a result of this study, shrinkage and swelling lead to an increase in TMRB. Moreover, swelling increased CO2 breakthrough time and decreased displacement ratio and CO2 storage for all ranks of coal. Low-rank coals are affected more negatively than high-rank coals by swelling. Furthermore, it was realized that dry coal reservoirs are more influenced by swelling than others and saturated wet coals are more suitable for eliminating the negative effects of CO2 injection. In addition, it was understood that it is possible to reduce swelling effect of CO2 on cleat permeability by mixing it with N2 before injection. However, an economical optimization is required for the selection of proper gas mixture. Finally, it is concluded from sensitivity analysis that elastic modulus is the most important parameter, except the initial cleat porosity, controlling SS in the extended P&M model by highly affecting TMRB. 相似文献
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The device is used for the coulometric titration of chloride with electrolytically generated silver ions and biamperometric end-point indication via a second pair of silver electrodes. The device consists of the external measuring cell with the generator- and indicator-electrode systems and a magnetic stirrer as well as the titrator proper, which contains all electric and electronic components for the realization of the course of measurements up to the digital display of measured values. Four modes of operation can be chosen with the units mmol/1 Cl? or mg Cl? in 100 ml sample and sample volumes of 50 μ and 200 μl the compensation of systematic dosing errors or the taking into account of constant matrix effects being possible by means of a steplessly adjustable correction factor between 0.95 and 1.05. The measuring range is 25 … 2,000 mg/1 Cl? with variability coefficients between 0.3 and 3% if a microlitre pipette with a PE pipette tip is used. An even lower variability of the results can be expected from an improved sample dosing Disturbances caused by ions subject to electrolytic redox processes were detected (Fe, S2?, CrO42?). 相似文献
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In this paper, we introduce a new method called Forced Neural Network (FNN) to find the parameters of the object in geophysical
section respect to gravity anomaly assuming the prismatic model. The aim of the geological modeling is to find the shape and
location of underground structure, which cause the anomalies, in 2D cross section. At the first stage, we use one neuron to
model the system and apply back propagation algorithm to find out the density difference. At the second level, quantization
is applied to the density differences and mean square error of the system is computed. This process goes on until the mean
square error of the system is small enough. First, we use FNN to two synthetic data, and then the Sivas–Gürün basin map in
Turkey is chosen as a real data application. Anomaly values of the cross section, which is taken from the gravity anomaly
map of Sivas–Gürün basin, are very close to those obtained from the proposed method. 相似文献
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A modified energy-balance equation accounting for P-delta effects and hysteretic behavior of reinforced concrete members is derived. Reduced hysteretic properties of structural components due to combined stiffness and strength degradation and pinching effects, and hysteretic damping are taken into account in a simple manner by utilizing plastic energy and seismic input energy modification factors. Having a pre-selected yield mechanism, energy balance of structure in inelastic range is considered. P-delta effects are included in derived equation by adding the external work of gravity loads to the work of equivalent inertia forces and equating the total external work to the modified plastic energy. Earthquake energy input to multi degree of freedom (MDOF) system is approximated by using the modal energy-decomposition. Energy-based base shear coefficients are verified by means of both pushover analysis and nonlinear time history (NLTH) analysis of several RC frames having different number of stories. NLTH analyses of frames are performed by using the time histories of ten scaled ground motions compatible with elastic design acceleration spectrum and fulfilling duration/amplitude related requirements of Turkish Seismic Design Code. The observed correlation between energy-based base shear force coefficients and the average base shear force coefficients of NLTH analyses provides a reasonable confidence in estimation of nonlinear base shear force capacity of frames by using the derived equation. 相似文献
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Onur Tan Eleftheria E. Papadimitriou Zumer Pabucçu Vassilis Karakostas Ahmet Yörük Kostas Leptokaropoulos 《Acta Geophysica》2014,62(6):1283-1309
A detailed investigation of microseismicity and fault plane solutions are used to determine the current tectonic activity of the prominent zone of seismicity near Samos Island and Kusadasi Bay. The activation of fault populations in this complex strike-slip and normal faulting system was investigated by using several thousand accurate earthquake locations obtained by applying a double-difference location method and waveform cross-correlation, appropriate for areas with relatively small seismogenic structures. The fault plane solutions, determined by both moment tensor waveform inversions and P-wave first motion polarities, reveal a clear NS trending extension direction, for strike slip, oblique normal and normal faults. The geometry of each segment is quite simple and indicates planar dislocations gently dipping with an average dip of 40–45°, maintaining a constant dip through the entire seismogenic layer, down to 15 km depth. 相似文献
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Onur ?al??kan ?hsan ?i?ek Andreas Matzarakis 《Theoretical and Applied Climatology》2012,107(3-4):417-425
Climate is an important resource for tourism and an equally important element that needs to be included in tourism promotions. This study reveals Bursa’s bioclimatological conditions. These conditions were identified by using physiologically equivalent temperature and a Climate–Tourism–Information–Scheme over 10-day periods and analyzing the mean thermal perception values that emerged. Evaluating bioclimatic conditions and meteorological parameters such as air temperature, duration of sunshine, number of wet days, amount of precipitation, and wind from the perspective of tourism will help people choose the best holiday times depending on their individual needs and circumstances. 相似文献
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Development of a GIS-based monitoring and management system for underground coal mining safety 总被引：2，自引：0，他引：2
Seda alap Mahmut Onur Karsl&#x;olu Nuray Demirel 《International Journal of Coal Geology》2009,80(2):105-112
Coal mine safety is of paramount concern to mining industry. Mine accidents have various causes and consequences including catastrophic failure of mine, substantial economic losses and most notably loss of lives. Therefore, any initiative in mine monitoring is of vital importance for progressing safety surveillance and maintenance.This paper presents the development of a geographic information system (GIS)-based monitoring and management system for underground mine safety in three levels as constructive safety, surveillance and maintenance, and emergency. The developed model integrates the database design and management to the monitoring system implementation which encompasses query and analysis operations with the help of web and desktop applications. Interactive object-oriented graphical user interfaces (GUIs) were developed to visualize information about the entities gathered from the model and also to provide analysis operations based on the graphical representations and demonstrations using data tables and map objects.The research methodology essentially encompasses five main stages: (i) designing a conceptual database model; (ii) development of a logical model in terms of entity-relationship (ER) diagrams; (iii) development of a physical model based on physical constraints and requirements; (iv) development of GUIs and implementation of the developed model, analysis and queries; (v) verification and validation of the created model for Ömerler underground coal mine in Turkey. The proposed system is expected to be an efficient tool for improving and maintaining healthy standards in underground coal mines which can possibly be extended to a national GIS infrastructure. 相似文献