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A Comprehensive Overview of the ELECTRE Method in Multi-Criteria Decision-Making 被引量:1
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作者 Hamed Taherdoost Mitra Madanchian 《Journal of Management Science & Engineering Research》 2023年第2期5-16,共12页
The ELECTRE(ELimination Et Choix Traduisant la REalite)method has gained widespread recognition as one of the most effective multi-criteria decision-making(MCDM)methods.Its versatility allows it to be applied in a wid... The ELECTRE(ELimination Et Choix Traduisant la REalite)method has gained widespread recognition as one of the most effective multi-criteria decision-making(MCDM)methods.Its versatility allows it to be applied in a wide range of areas such as engineering,economics,business,environmental management and many others.This paper aims to provide an overview of the ELECTRE method,including its fundamental concepts,applications,advantages,and limitations.At its core,the ELECTRE method is an outranking family of MCDM techniques,which allows for the direct comparison of alternatives based on a set of criteria.The method takes into account the preferences and importance of decision-makers and generates a ranking of the alternatives based on their relative strengths and weaknesses.The ELECTRE method is a powerful tool for decision-making,and its applicability to a wide range of fields demonstrates its versatility and adaptability.By understanding its concepts,applications,merits,and demerits,decision-makers can use the ELECTRE method to make informed and effective decisions in a variety of contexts. 展开更多
关键词 Decision making Multi criteria decision making ELECTRE method ELimination Et Choix Traduisant la REalite method Multi attribute decision making
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Road Layout Cuts Volume Evaluation by Electrical Resistivity Tomography: Case Study of Gagnoa-Gueyo-Bamenadou Road Project
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作者 Kouamelan Serge Kouamelan Assi Martial Yapo +1 位作者 Yacouba Ouattara Eric Thompson Brantson 《Journal of Geoscience and Environment Protection》 2024年第10期38-54,共17页
A study of excavated material on the Gagnoa-Guéyo-Bamenadou road project in southwest Côte d’Ivoire was carried out using electrical resistivity tomography with a dipole-dipole configuration. This study aim... A study of excavated material on the Gagnoa-Guéyo-Bamenadou road project in southwest Côte d’Ivoire was carried out using electrical resistivity tomography with a dipole-dipole configuration. This study aimed to determine the nature and volume of the studied cuts. Based on the cumulative distances of the longitudinal sections of the road alignment superimposed on the tomographic profiles, a cumulative volume of 104681 m3 of material was determined. This volume comprises 88557 m3 of soft cuts and 16,124 m3 of rocky cuts, which can be reused in specific embankment zones. This work may, therefore be useful in the characterization of cuts in a preliminary design study, in order to anticipate changes during the road’s development and asphalting. 展开更多
关键词 Electrical method Longitudinal Section CUT Soft and Rocky Materials Côte d’Ivoire
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A new measurement method of crack propagation rate for brittle rock under THMC coupling condition 被引量:7
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作者 Wei YI Qiu-hua RAO +1 位作者 Zhuo LI Qing-qing SHEN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第8期1728-1736,共9页
A new electrical method of conductive carbon-film(with waterproof and anticorrosion ability)was proposed to continuously measure crack propagation rate of brittle rock under THMC coupling condition.A self-designed cou... A new electrical method of conductive carbon-film(with waterproof and anticorrosion ability)was proposed to continuously measure crack propagation rate of brittle rock under THMC coupling condition.A self-designed coupling testing system was used to conduct THMC coupling fracture tests of the pre-cracked red sandstone specimens(where the temperature is only changed)by this new electrical method of conductive carbon-film.Calculation results obtained by the energy method coincide well with the test results.And the higher the temperature is,the earlier the crack is initiated and the larger the crack propagation rate and accelerated velocity are,which can prove the validity of the new electrical method.This new electrical method has advantages of continuously measuring crack propagation rate over the conventional electrical,optical and acoustic methods,and can provide important basis for safety assessment and cracking-arrest design of deep rock mass engineering. 展开更多
关键词 crack propagation rate electrical method of conductive carbon-film thermo-hydro-mechanical-chemical coupling energy method brittle rock
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ELECTRIC REGENERATION METHOD OF IONEXCHANGE RESIN IN THE MIXED BED 被引量:2
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作者 Wang Fang 《Chinese Journal of Reactive Polymers》 1998年第2期68-74,共7页
In this paper the self-regeneration process of the mixed resins consisting of cationand anion ion exchangers in the electrolialyser of the packed bed is analyzed and anelectric regeneration method is put forward to su... In this paper the self-regeneration process of the mixed resins consisting of cationand anion ion exchangers in the electrolialyser of the packed bed is analyzed and anelectric regeneration method is put forward to supply the desalinated water by mixedbed The electric regeneration technology is a new one used for regeneration of theexhausted ion exchangers in the mixed bed instead of the traditional regeneratingprocess by using acid and abc liquor Electric energy is consumed to regenerat theion exchangers loaded by salts from water treatment without any chemicals- acid alkali. The advantage of the electric regeneration process edibited convenientoperation, no discharge any waste, and therefore no Polluted to the recehang waterbode and the environmental ground 展开更多
关键词 Electric regeneration method of ion exchange resin Membranetechnology Pollution control
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Study on the Pyrolytic Carbon Generated by the Electric Heating CVD Method 被引量:1
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作者 徐先锋 欧阳甜 +1 位作者 ZENG Lingsheng CHAI Lingzhi 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2018年第2期409-413,共5页
A new method of fabricating C/C composite materials, namely electric heating CVD method, was used, which electrified the carbon fiber directly by using the conductivity of itself. Acetylene was used as the carbon sour... A new method of fabricating C/C composite materials, namely electric heating CVD method, was used, which electrified the carbon fiber directly by using the conductivity of itself. Acetylene was used as the carbon source with nitrogen as dilution gas, and the pyrolytic carbon started to deposit on the carbon fiber surface when the deposition temperature was reached. The morphology of pyrolytic carbon was characterized by SEM, and the surface properties of carbon fibers before and after CVD were characterized by Raman spectroscopy. The experimental results show that the electric heating method is a novel method to fabricate C/C composite materials, which can form a dense C/C composite material in a short time. The order degree and the average crystallite size of the carbon fiber surface were decreased after the experiment. 展开更多
关键词 C/C composite materials electric heating method chemical vapor deposition pyrolytic carbon
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Catalytic CVD Growth of Carbon Nanotubes by Electric Heating Method
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作者 徐先锋 欧阳甜 +3 位作者 CHAI Lingzhi ZENG Lingsheng LI Gang CHEN Yue 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2017年第1期136-139,共4页
Carbon nanotubes(CNTs) were synthesized by the electric heating catalytic chemical deposition method(CCVD) using acetylene(C2H2) as the carbon source and nitrogen(N2) as carrier gas,and nickel catalyst was loa... Carbon nanotubes(CNTs) were synthesized by the electric heating catalytic chemical deposition method(CCVD) using acetylene(C2H2) as the carbon source and nitrogen(N2) as carrier gas,and nickel catalyst was loaded by electroplating.The electric heating method,as a new method,electrifies the carbon fiber directly by using its conductivity.The morphology and structure of CNTs were characterized by SEM and TEM,and the surface properties of carbon fibers before and after the growth of CNT were characterized by Raman spectroscopy.The experimental results show that the electric heating method is a new method to produce CNT,and can grow a large number of CNTs in a short time,the crystallization degree and surface average crystallite size of carbon fiber increased after the growth of CNT on it.In addition,electroplating loading catalyst can also be used as an ideal loading way,which can control the number,shape,and distribution of nickel particles by controlling the plating time. 展开更多
关键词 electric heating method catalytic CVD nickel plating carbon nanotubes
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NUMERICAL SIMULATION FOR MEASURING ATMOSPHERE CARBON POTENTIAL BY ELECTRIC RESISTANCE METHOD
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作者 W.M. Zhang M.J. Hu +1 位作者 Y.J. Li J.S. Pan and X. Chen( 1) Open Lab. of the Educational Ministry for High Temperature Material and Test, Shanghai Jiaotong University,Shanghai 200030, China 2) Oregen Graduate Institute of Science and Technology, USA) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2000年第2期811-815,共5页
According to computer numerical simulation for measuring atmosphere carbon potential by electric resistance method (hot-wire method) and the experimental data, the paper point out that the measuring result dose not d... According to computer numerical simulation for measuring atmosphere carbon potential by electric resistance method (hot-wire method) and the experimental data, the paper point out that the measuring result dose not directly reflect the atmosphere carbon potential (Cg) but the average carbon content, and as a result, the change of electric resistance obviously lag to that of the atmosphere carbon potential. In order to correctly control the carbon potential by electric resistance method, the authors bring forward a function which is a better expression for the relationship between the average carbon content of the wire and the atmosphere carbon potential and ensures good carbon potential control. 展开更多
关键词 electric resistance method carbon potential computer simulation
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Improved Efficiency Test Method for the Motor Controller with SiC MOSFETs
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作者 Wei Wang Qiang Song +1 位作者 Yiting Li Mukhtiar Ahmad 《Journal of Beijing Institute of Technology》 EI CAS 2020年第3期294-302,共9页
The traditional measurement method was inaccurate to evaluate the motor controller efficiency,which the measurement efficiency value could be more than 100%in practical testing experiments.To deal with this issue,an i... The traditional measurement method was inaccurate to evaluate the motor controller efficiency,which the measurement efficiency value could be more than 100%in practical testing experiments.To deal with this issue,an improved electrical measurement method for the motor controller efficiency is proposed in this paper,which is established by analyzing the power loss distribution and phase currents of the motor controller.It is demonstrated that the SiC MOSFET chips are the main power loss devices in the motor controller,accounting for more than 93.1%of the total power loss.The accuracy of the proposed method is compared with the traditional method in simulation.It shows that the test error of the efficiency obtained by the traditional method fluctuates on a large scale,which varied from 0.094%to 1.911%.Compared with the traditional method,the test error of the proposed method appears to be less than 0.083%,which provides significant guidance for the motor controller efficiency test and design. 展开更多
关键词 electrical measurement method motor controller efficiency power loss distribution SiC MOSFET
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Analysis of floor failure depth by using electric profiling method in longwall gangue backfill mining
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作者 Sheng-Li YANG Xin-Pin DING +2 位作者 Xin WANG Xiao-Meng LI Li LIN 《Journal of Coal Science & Engineering(China)》 2013年第3期282-289,共8页
In underground mining, floor failure depth accompanying mining phases usually results from changes in the advance abutment pressure in the coal mass, and changes in stress redistribution in the areas that have already... In underground mining, floor failure depth accompanying mining phases usually results from changes in the advance abutment pressure in the coal mass, and changes in stress redistribution in the areas that have already been mined. Although a variety of techniques have been applied to determine the failure depth, and a number of studies have provided the evidence for the decreasing of failure depth under backfilling, these methods and interactions have not been unequivocally identified. Based on the premise of one possible relation between the failure depth and filling body, which is that the filling materials (gangue) in the gob area can not only restrain the movement of the overlying strata effectively, but also can help to decrease failure depth of the floor in the coal mine. The failure depth in a specific longwall gangue backfilling mine was measured using the mine electricity profiling method. These electrode cables are arranged in a crossheading order to measure the depth and position of the destroyed floor using the DC method. After this, several different methods were used to interpret the recorded data from the field study for gaining failure depth, and the results were compared to the theoretical calculation values. And finally, the authors analyzed the reasons for failure depth form values recorded not indicating a large decrease trend when compared to the theoretical calculation. In this area, it is found that: ① The results using the mine electricity profiling method turns out to be robust and can be used in predicting floor failure depth, and the horizontal position of the maximum destroyed in working face of longwall backfilling. The maximum destroyed position and failure space of the floor can be identified by using this method. ②There is a time-delay processing between the advance of the working face and the failure of floor strata in the mining processing. ③Additionally, based on the data collected from field measurements, which includes three different test electrode spacing approaches (single, double and triple electrode spacing), and the theoretical value from theoretical calculations. The premise mentioned above cannot be supported during the specific field test, and the role of the filling body in the mined area cannot decrease the floor failure depth effectively in comparison to the theory predictions. Basically, the failure depths in the two different methods have similar results and it is possible that there will not be a direct correlation between the filling body and failure depth. ④Although the failure depth cannot decrease effectiveness when using gangue backfilling in the field testing, due to gob gangue, filling materials being able to deliver the abutment pressure from the overburden in most cases, once they were compacted and rammed by the overburden pressure, it still can make the fracture of the gob area clog and be further consolidated. In this way, it is assumed that water-bursting accidents can be prevented effectively under backfill mining. For this reason, gangue backfilling may make a significant contribution to safety mining. 展开更多
关键词 gangue backfilling floor failure depth electricity profiling method gob area
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Application Analysis of Various Geophysical Methods in Volume Calculation of Different Landfills
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作者 Jinsuo Liu Biao Jin 《Open Journal of Geology》 CAS 2022年第9期706-716,共11页
Garbage disposal has gradually become a key issue faced by environmental governance. What must be controlled in garbage disposal is the calculation of garbage volume. In this paper, according to the different landfill... Garbage disposal has gradually become a key issue faced by environmental governance. What must be controlled in garbage disposal is the calculation of garbage volume. In this paper, according to the different landfill conditions of a landfill in Anhui, including: covering soil, overlying HDPE membrane, overlying concrete, etc., combined with the physical differences between the rock mass and the garbage at the bottom of the landfill. The landfill covered with HDPE membrane adopts the transient electromagnetic method, the landfill covered with soil layer adopts the high-density electrical method, and the landfill covered with concrete adopts the combination of transient electromagnetic method and ground penetrating radar. At the same time, Combines the borehole data to determine that the resistivity value of the interface between the garbage and the soil was 29 Ω&sdot;m. Finally, the sections of multiple survey lines can accomplish three-dimensional stereoscopic that calculate the distribution and actual volume of the garbage. This method is used to determine the final investment cost. 展开更多
关键词 Garbage Volume Geophysical Exploration Transient Electromagnetic method High-Density Electrical method Ground Penetrating Radar
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Simulation Monitoring for Rainfall Infiltration in Soil Based on High Density Electrical Method
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作者 Shanshan Lv Dengke He 《Journal of Geoscience and Environment Protection》 2021年第5期1-7,共7页
<div style="text-align:justify;"> Rainfall infiltration is a porous medium flow problem with variable saturation. Based on the theoretical analysis of the flow field, electrical conductivity of rocks, ... <div style="text-align:justify;"> Rainfall infiltration is a porous medium flow problem with variable saturation. Based on the theoretical analysis of the flow field, electrical conductivity of rocks, the electrical field, the paper simulates the coupling relationship between the water saturation in soil and the apparent resistivity distribution. It combines the Richards equation, the Archie formula and the Laplace equation. The experiment simulates the potential field data by the Wenner setting in electrical exploration on a two-layer geologic model with continuous rainfall during 5 days, which shows that the effective saturation in soil is increasing with the rainfall time, while the apparent resistivity is decreasing. This can provide a theoretical basis for the analyzing the rainfall infiltration and porosity of the soil by using high-density electrical method in the future. </div> 展开更多
关键词 Rainfall Infiltration Multi Physical Field Coupling Numerical Simulation High Density Electrical method
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Thermal stability and electrical transport properties of Ge/Sn-codoped single crystalline β-Zn4Sb3 prepared by the Sn-flux method
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作者 Hong-xia Liu Shu-ping Deng +2 位作者 De-cong Li Lan-xian Shen Shu-kang Deng 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第2期441-445,共5页
This study prepares a group of single crystalline β-Zn_4Sb_3 with Ge and Sn codoped by the Sn-flux method according to the nominal stoichiometric ratios of Zn_(4.4)Sb_3 Ge_xSn_3(x = 0–0.15). The prepared samples... This study prepares a group of single crystalline β-Zn_4Sb_3 with Ge and Sn codoped by the Sn-flux method according to the nominal stoichiometric ratios of Zn_(4.4)Sb_3 Ge_xSn_3(x = 0–0.15). The prepared samples possess a metallic luster surface with perfect appearance and large crystal sizes. The microscopic cracks or defects are invisible in the samples from the back-scattered electron image. Except for the heavily Ge-doped sample of x = 0.15, all the samples are single phase with space group R3c. The thermal analysis results show that the samples doped with Ge exhibit an excellent thermal stability.Compared with the polycrystalline Ge-substituted β-Zn_4Sb_3, the present single crystals have higher carrier mobility, and hence the electrical conductivity is improved, which reaches 7.48×10~4S·m^(-1) at room temperature for the x = 0.1 sample.The change of Ge and Sn contents does not improve the Seebeck coefficient significantly. Benefiting from the increased electrical conductivity, the sample with x = 0.075 gets the highest power factor of 1.45×10^(-3)W·m^(-1)·K^(-2) at 543 K. 展开更多
关键词 thermoelectric materials β-Zn4Sb3 flux method electrical transport properties
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EVOLUTION OF CREEP-FATIGUE DAMAGE IN TYPE 304STAINLESS STEEL AND ITS DETECTION BY ELECTRICALPOTENTIAL METHOD
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作者 N.Tada T.Kitamura +1 位作者 R.Ohtani E.Nakayama 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1998年第6期463-469,共7页
Creep-fatigue test was carried out using smooth round bar specimens of Type 304 stainless steel. Cavities and small cracks on the cross-section of the specimen were carefully observed by a scanning laser microscope. ... Creep-fatigue test was carried out using smooth round bar specimens of Type 304 stainless steel. Cavities and small cracks on the cross-section of the specimen were carefully observed by a scanning laser microscope. Moreover, direct current electrical potential method (DC-EPM) was applied in order to evaluate non-destructively the distribution of internal cracks. The distribution evaluated by DC-EPM agrees well with the actual one. (Edited author abstract) 9 Refs. 展开更多
关键词 CREEP-FATIGUE CAVITY small crack Type 304 stainless steel electrical potential method
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Obtaining 2D Soil Resistance Profiles from the Integration of Electrical Resistivity Data and Standard Penetration Test (SPT) and Light Dynamic Penetrometer (DPL) Resistance Tests—Applications in Mass Movements Studies
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作者 Cassiano Antonio Bortolozo Tatiana Sussel Gonçalves Mendes +10 位作者 Mariana Ferreira Benessiuti Motta Silvio Jorge Coelho Simões Tristan Pryer Daniel Metodiev Marcio Roberto Magalhães de Andrade Maiconn Vinicius de Moraes Danielle Silva de Paula Nélio José Bastos Luana Albertani Pampuch Rodolfo Moreda Mendes Marcio Augusto Ernesto de Moraes 《International Journal of Geosciences》 2023年第9期840-854,共15页
In Brazil and various regions globally, the initiation of landslides is frequently associated with rainfall;yet the spatial arrangement of geological structures and stratification considerably influences landslide occ... In Brazil and various regions globally, the initiation of landslides is frequently associated with rainfall;yet the spatial arrangement of geological structures and stratification considerably influences landslide occurrences. The multifaceted nature of these influences makes the surveillance of mass movements a highly intricate task, requiring an understanding of numerous interdependent variables. Recent years have seen an emergence in scholarly research aimed at integrating geophysical and geotechnical methodologies. The conjoint examination of geophysical and geotechnical data offers an enhanced perspective into subsurface structures. Within this work, a methodology is proposed for the synchronous analysis of electrical resistivity geophysical data and geotechnical data, specifically those extracted from the Light Dynamic Penetrometer (DPL) and Standard Penetration Test (SPT). This study involved a linear fitting process to correlate resistivity with N10/SPT N-values from DPL/SPT soundings, culminating in a 2D profile of N10/SPT N-values predicated on electrical profiles. The findings of this research furnish invaluable insights into slope stability by allowing for a two-dimensional representation of penetration resistance properties. Through the synthesis of geophysical and geotechnical data, this project aims to augment the comprehension of subsurface conditions, with potential implications for refining landslide risk evaluations. This endeavor offers insight into the formulation of more effective and precise slope management protocols and disaster prevention strategies. 展开更多
关键词 GEOPHYSICS Geotechnical Data Electrical Resistivity method Standard Penetration Test (SPT) Light Dynamic Penetrometer (DPL) Mass Movements
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Three-dimensional inversion of borehole-surface electrical data based on quasi-analytical approximation 被引量:5
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作者 Wang Zhigang He Zhanxiang Liu Haiying 《Applied Geophysics》 SCIE CSCD 2006年第3期141-147,共7页
3D inversion of borehole-surface electrical data for complex geo-electrical models is still a challenging problem in geophysical exploration. We have developed a program for 3D inversion to borehole-surface electrical... 3D inversion of borehole-surface electrical data for complex geo-electrical models is still a challenging problem in geophysical exploration. We have developed a program for 3D inversion to borehole-surface electrical data based on the quasi-analytical approximation (QA) and re-weighted regularized conjugate gradient method (RRCG) algorithms using Visual Fortran 6.5. Application of the QA approximation to forward modeling and Frechet derivative computations speeds up the calculation dramatically. The trial calculation for synthetic data of theoretical model showed that the program is fast and highly precise. 展开更多
关键词 Borehole-surface electrical method quasi-analytical approximation integral equation method re-weighted regularized conjugate gradient method
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Crack initiation rate of brittle rock under thermal-hydro-mechanical coupling condition 被引量:2
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作者 Zhuo LI Qiu-hua RAO +1 位作者 Peng LI Wei YI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第10期2107-2113,共7页
A calculation formula of thermal-hydro-mechanical(THM)coupling crack initiation rate for brittle rock was derived based on the energy conservation law.The self-designed THM coupling fracture test with conductive adhe... A calculation formula of thermal-hydro-mechanical(THM)coupling crack initiation rate for brittle rock was derived based on the energy conservation law.The self-designed THM coupling fracture test with conductive adhesive electrical measurement method was applied to measuring the THM coupling crack propagation rate of brittle rock continuously.Research results show that both calculation and test results of crack initiation rate increased with increase of the temperature and the hydraulic pressure.They are almost in good agreement,which can prove validity of the calculation formula of THM coupling crack initiation rate. 展开更多
关键词 crack initiation rate thermal-hydro-mechanical coupling test conductive adhesive electrical method fracture mechanism brittle rock
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Twelve Elastic Constants of Betula platyphylla Suk. 被引量:1
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作者 WangLiyu LuZhenyou 《Forestry Studies in China》 CAS 2004年第1期37-41,共5页
Wood elastic constants are needed to describe the elastic behaviors of wood and be taken as an important design parameter for wood-based composite materials and structural materials. This paper clarified the relations... Wood elastic constants are needed to describe the elastic behaviors of wood and be taken as an important design parameter for wood-based composite materials and structural materials. This paper clarified the relationships between compliance coefficients and engineering elastic constants combined with orthotropic properties of wood, and twelve elastic constants of Betula platyphylla Suk. were measured by electrical strain gauges. Spreading the adhesive quantity cannot be excessive or too little when the strain flakes were glued. If excessive, the glue layer was too thick which would influence the strain flakes?performance, and if too little, glues plastered were not firm, which could not accurately transmit the strain. Wood as an orthotropic material, its modulus of elasticity and poissons ratios are related by two formulas:μij /Ei =μji /Ej and μij < (Ei /Ej)1/2. The results showed that the elastic constants of Betula platyphylla Suk. measured by electrical strain gauges were accurate and reliable. The results of shear elastic modulus GTL and GLR show a high linear regression correlation coefficient (> 0.95) between the reciprocal of elastic modulus MOE-1 and the square of the ratio of depth to length (h/l)2, which indicate that shear modulus values measured were reliable by three point bending experiment. 展开更多
关键词 WOOD method of electrical measurement elastic constant
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Simulation Test for Evolution Laws of Tensile Fractures in a Coal Mining Area
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作者 Zhang Jinman Zhang Kun +2 位作者 Li Jiewei Zhao Ling Zhou Liang 《Meteorological and Environmental Research》 CAS 2018年第4期85-88,共4页
In order to study evolution laws of tensile fractures in a coal mining area, based on the classification of the fractures formed by mining, a physical simulation test was carried out to simulate the dynamic evolut... In order to study evolution laws of tensile fractures in a coal mining area, based on the classification of the fractures formed by mining, a physical simulation test was carried out to simulate the dynamic evolution process of tensile fractures in coal mining areas. The results showed that after the coal in the mining area was mined, the mining area underwent obvious movement and deformation and forms tensile fractures. As the min-ing working face was advanced, the tensile fractures underwent the dynamic process of generation, development and closure. The changing curves of density of tensile fractures with the increase of mining length of the working face liked a ladder (it increased slowly and then rapidly) and then had two peaks (the second peak was higher than the first peak). 展开更多
关键词 Coal mining areas Physical simulation Parallel electric method Tensile fractures Evolution laws
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New Scenarios for a Shift towards Agroecology in Viticulture
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作者 Nawel Aouadi Francis Macary +1 位作者 Laurent Delière Jean-Philippe Roby 《Agricultural Sciences》 2021年第10期1003-1033,共31页
In the light of its negative impacts on the environment and human health, conventional agriculture is currently facing new challenges;for example, reducing pesticide reliance, improving biodiversity, adapting to clima... In the light of its negative impacts on the environment and human health, conventional agriculture is currently facing new challenges;for example, reducing pesticide reliance, improving biodiversity, adapting to climate change and reconciling winegrowers with consumers, which require changes to be made to vineyard management. A shift towards more sustainable agriculture via the development of agroecological systems may be key to meeting these environmental, economic and social challenges. This study aimed to evaluate the performance of existing viticultural systems, as well as that of three new scenarios that we built to change conventional vine production systems and their related practices. The end aim is to adopt the principles of agroecology, and more virtuously, to ensure that vine production remains in line with societal expectations. First, thirty-eight different viticultural systems were chosen. Three realistic scenarios for changing these production systems were then built by working with stakeholders and incorporating the best practices that had been identified in the vineyard. Conventional practices were optimised in the first scenario and an agroecological approach was adopted for the other two scenarios: an Agroecological scenario (using synthetic chemicals) and an Agroecological-Bio scenario (organic system). All three scenarios were based on a combination of good practices which contribute to enhancing vineyard biodiversity, and which thus restore biological regulation and in turn reduce pesticides. The viticultural systems performances have been evaluated with a methodology involving multicriteria decision aid using ELECTRE Tri-C and ELECTRE III methods. Seven evaluation criteria were selected which covered socio-economic performance (economic profitability, workload and system complexity) and environmental performance (pesticide pressure, pesticide ecotoxicity, agroecological practices and pesticide drift). The best performances were achieved by the two agroecological scenarios, and this methodology can be adaptable to different production systems everywhere in different viticultural regions. 展开更多
关键词 Viticultural System AGROECOLOGY BIODIVERSITY PESTICIDES Multicriteria Decision Aid methods ELECTRE methods
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Electrical Resistivity Sounding for Groundwater Investigation around Enugu Metropolis and the Environs, Southeast Nigeria
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作者 Claris C. Nwachukwu Charles C. Ugbor Osim Jethro Ogboke 《International Journal of Geosciences》 2022年第1期54-70,共17页
This report evaluates the use of electrical method and borehole data to investigate the subsurface to delineate the groundwater potential in Enugu metropolis and the environs, south-eastern Nigeria other than rely onl... This report evaluates the use of electrical method and borehole data to investigate the subsurface to delineate the groundwater potential in Enugu metropolis and the environs, south-eastern Nigeria other than rely only on resistivity method w</span><span style="font-family:Verdana;">hich could lead to interpretation error. Integrating these 2 data sets is key in this study. The study area is located in the Anambra Basin and is underlain by Nkporo/Enugu Shale which is overlain by the Mamu Formation. It is bounded by Latitudes 6</span><span style="font-family:Verdana;"><span style="white-space:nowrap;">&#176;</span>2 0'00</span></span><span style="font-family:Verdana;">"</span><span style="font-family:Verdana;">N to 6<span style="white-space:nowrap;">&#176;</span>30'00</span><span style="font-family:Verdana;">"</span><span style="font-family:Verdana;">N and Longitudes 7<span style="white-space:nowrap;">&#176;</span>25'00</span><span style="font-family:Verdana;">"</span><span style="font-family:Verdana;">E to 7<span style="white-space:nowrap;">&#176;</span>35'00</span><span style="font-family:Verdana;">"</span><span style="font-family:""><span style="font-family:Verdana;">E and covers surface area of about 342 m</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;">. Thirty</span></span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">one vertical electrical soundings (VES) were carried out across the area using the Schlumberger electrode array with current electrode separation from 2 to 500 m to identify the depths and resistivity values of the identified geo-electric layers. Through data analysis using WinResist software, the apparent resistivity, thicknesses and depths and the thicknesses of the aquifers were generated. The resistivity</span><span style="font-family:""> </span><span style="font-family:Verdana;">and depths were modelled to generate resistivity map and depth map. The resistivity of the aquiferous zone within the study area varie</span><span style="font-family:Verdana;">d</span><span style="font-family:Verdana;"> from 20.55</span><span style="font-family:""> - </span><span style="font-family:Verdana;">427.8 ohm-m at depths of between 10.7</span> - <span style="font-family:Verdana;">40.05 m. Depth to the water table appears to be shallow at the south western part of the map. The interpreted geo-electric layers show a sequence of lateritic top soil, shale, sand and shale. The frequency distribution of the VES curves generated shows the presence of 3 to 5 layers with HK type as the highest. Also, a 2D model was generated using the correlation of VES to VES data and borehole data to VES data to show the underlying stratigraphy beneath the study area as well as the direction of ground water flow. Result of the VES curve analysis reveal</span><span style="font-family:Verdana;">s</span><span style="font-family:Verdana;"> that the sub-surface is underlain by three lithological layers namely: lateritic top soil, shale, sand and shales with NW direction of groundwater flow from the 2D model. Groundwater prospective zones can be seen along NW, SW and central parts of the study area which have low resistivity values. 展开更多
关键词 Electrical method Vertical Electrical Sounding GROUNDWATER AQUIFER Apparent Resistivity
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