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试论朦胧诗的模糊性与象征手法
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作者 韩芍夷 《海南师范学院学报(社会科学版)》 2005年第6期114-117,共4页
文章从“朦胧诗”一词的导源、释名入手,指出了朦胧诗主题的模糊性存在两种情形,一是晦涩型(即诗意艰深难懂);二是多值型(即诗意亦此亦彼)。认为朦胧诗的模糊性有着多种致因,但最主要最直接的还是象征手法使然。象征的主要特征是“暗示... 文章从“朦胧诗”一词的导源、释名入手,指出了朦胧诗主题的模糊性存在两种情形,一是晦涩型(即诗意艰深难懂);二是多值型(即诗意亦此亦彼)。认为朦胧诗的模糊性有着多种致因,但最主要最直接的还是象征手法使然。象征的主要特征是“暗示性”(即通过某一特定形象以表现或暗示超越这一形象的含义)。象征的生成机制是相关事物间的“可拟性”(即相互对应关系)。由于社会历史环境和政治文化背景、西方现代文艺思潮以及我国传统诗论的多重影响,诗人往往选择象征手法进行创作。而正是由于象征所具有的涵盖性及主观随意性等特质,导致了朦胧诗主题的模糊性。文章从“量变到质变”的哲学思辨角度,指出了朦胧诗的“朦胧度”应有的极限。 展开更多
关键词 朦胧诗 模糊 晦涩型 多值型 象征手法 暗示 可拟性
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Material driven workability simulation by FEM including 3D processing maps for magnesium alloy 被引量:2
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作者 刘娟 李居强 +2 位作者 崔振山 欧立安 阮立群 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第10期3011-3019,共9页
The three-dimensional (3D) processing maps considering strain based on the two-dimensional (2D) processing maps proposed by PRASAD can describe the distribution of the efficiency of power dissipation and flow inst... The three-dimensional (3D) processing maps considering strain based on the two-dimensional (2D) processing maps proposed by PRASAD can describe the distribution of the efficiency of power dissipation and flow instability regions at various temperatures, strain rates and strains, which exhibit intrinsic workability related to material itself. Finite element (FE) simulation can obtain the distribution of strain, strain rate, temperature and die filling status, which indicates state-of-stress (SOS) workability decided by die shape and different processing conditions. On the basis of this, a new material driven analysis method for hot deformation was put forward by the combination of FE simulation with 3D processing maps, which can demonstrate material workability of the entire hot deformation process including SOS workability and intrinsic workability. The hot forging process for hard-to-work metal magnesium alloy was studied, and the 3D thermomechanical FE simulation including 3D processing maps of complex hot forging spur bevel gear was first conducted. The hot forging experiments were carried out. The results show that the new method is reasonable and suitable to determine the aoorooriate nrocess narameters. 展开更多
关键词 material driven workability simulation 3D processing maps magnesium alloy hot forging
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On reducibility of a class of nonlinear quasi-periodic systems with small perturbational parameters near equilibrium 被引量:2
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作者 李佳 朱春鹏 《Journal of Southeast University(English Edition)》 EI CAS 2012年第2期256-260,共5页
Consider the reducibility of a class of nonlinear quasi-periodic systems with multiple eigenvalues under perturbational hypothesis in the neighborhood of equilibrium. That is, consider the following system x = (A + ... Consider the reducibility of a class of nonlinear quasi-periodic systems with multiple eigenvalues under perturbational hypothesis in the neighborhood of equilibrium. That is, consider the following system x = (A + εQ( t) )x + eg(t) + h(x, t), where A is a constant matrix with multiple eigenvalues; h = O(x2) (x-4)) ; and h(x, t), Q(t), and g(t) are analytic quasi-periodic with respect to t with the same frequencies. Under suitable hypotheses of non-resonance conditions and non-degeneracy conditions, for most sufficiently small ε, the system can be reducible to a nonlinear quasi-periodic system with an equilibrium point by means of a quasi-periodic transformation. 展开更多
关键词 QUASI-PERIODIC REDUCIBLE non-resonance condition non-degeneracy condition KAM iteration
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A Dormant Multi-Controller Model for Software Defined Networking 被引量:11
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作者 FU Yonghong BI Jun +3 位作者 WU Jianping CHEN Ze WANG Ke LUO Min 《China Communications》 SCIE CSCD 2014年第3期45-55,共11页
In order to improve the scalability and reliability of Software Defined Networking(SDN),many studies use multiple controllers to constitute logically centralized control plane to provide load balancing and fail over.I... In order to improve the scalability and reliability of Software Defined Networking(SDN),many studies use multiple controllers to constitute logically centralized control plane to provide load balancing and fail over.In this paper,we develop a flexible dormant multi-controller model based on the centralized multi-controller architecture.The dormant multi-controller model allows part of controllers to enter the dormant state under light traffic condition for saving system cost.Meanwhile,through queueing analysis,various performance measures of the system can be obtained.Moreover,we analyze the real traffic of China Education Network and use the results as the parameters of computer simulation and verify the effects of parameters on the system characteristics.Finally,a total expected cost function is established,and genetic algorithm is employed to find the optimal values of various parameters to minimize system cost for the deployment decision making. 展开更多
关键词 Software Defined Networking MULTI-CONTROLLER queueing theory PERFORMANCEEVALUATION
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Approximate Reachability and Bisimulation Equivalences for Transition Systems 被引量:1
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作者 王超 吴尽昭 +1 位作者 谭红艳 付军 《Transactions of Tianjin University》 EI CAS 2016年第1期19-23,共5页
Using Baire metric, this paper proposes a generalized framework of transition system approximation by developing the notions of approximate reachability and approximate bisimulation equivalences. The proposed framewor... Using Baire metric, this paper proposes a generalized framework of transition system approximation by developing the notions of approximate reachability and approximate bisimulation equivalences. The proposed framework captures the traditional exact equivalence as a special case. Approximate reachability equivalence is coarser than approximate bisimulation equivalence, just like the hierarchy of the exact ones. Both approximate equivalences satisfy the transitive property, consequently, they can be used in transition system approximation. 展开更多
关键词 approximate equivalence REACHABILITY BISIMULATION transition system
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Availability-based simulation and optimization modeling framework for open-pit mine truck allocation under dynamic constraints 被引量:8
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作者 Mena Rodrigo Zio Enrico +1 位作者 Kristjanpoller Fredy Arata Adolfo 《International Journal of Mining Science and Technology》 SCIE EI 2013年第1期113-119,共7页
We present a novel system productivity simulation and optimization modeling framework in which equipment availability is a variable in the expected productivity function of the system. The framework is used for alloca... We present a novel system productivity simulation and optimization modeling framework in which equipment availability is a variable in the expected productivity function of the system. The framework is used for allocating trucks by route according to their operating performances in a truck-shovel system of an open-pit mine, so as to maximize the overall productivity of the fleet. We implement the framework in an originally designed and specifically developed simulator-optimizer software tool. We make an application on a real open-pit mine case study taking into account the stochasticity of the equipment behavior and environment. The total system production values obtained with and without considering the equipment reliability, availability and maintainability (RAM) characteristics are compared. We show that by taking into account the truck and shovel RAM aspects, we can maximize the total production of the system and obtain specific information on the production availability and productivity of its components. 展开更多
关键词 Simulation Optimization Reliability Productivity Open-pit Truck allocation
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Simulation analysis of construction process of high rock slope's stabilization 被引量:2
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作者 朱占元 凌贤长 +1 位作者 王宣青 邹祖银 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2008年第2期188-193,共6页
A self-developed elasto-plastic finite element program was used to analyze the construction sequence of high rock slope's stabilization in a coal-coking plant, and the result was compared with that employing the u... A self-developed elasto-plastic finite element program was used to analyze the construction sequence of high rock slope's stabilization in a coal-coking plant, and the result was compared with that employing the ultimate equilibrium method. Based on the results of finite element analysis, the stress contour graphs and displacement vector graphs at different construction steps were obtained, and the behavior of the slope during stabilization construction process was analyzed quantitatively. Based on the analysis of safety factors of three different schemes of stabilization and two different construction schemes, the assessment of stability and bracing design of the construction process were performed. The results show that the original reinforcement design is improper; the stability of the rock slope is controlled by a developed structural plane, the stability factor after excavation is less than 1, and the free surface should be braced in time; for stability, the construction sequence should adopt that bracing follows excavation step by step up to down; the local slide occurred during the construction process agrees with the dangerous slide determined by the numerical analysis, which proves the validity and rationality of the adopted method. 展开更多
关键词 high rock slope STABILITY STABILIZATION construction process simulation elasto-plastic FEM method
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Stability and reliability of pit slopes in surface mining combined with underground mining in Tonglushan mine 被引量:10
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作者 罗一忠 吴爱祥 +1 位作者 刘湘平 王洪江 《Journal of Central South University of Technology》 EI 2004年第4期434-439,共6页
Slope stability is of critical importance in the process of surface-underground mining combination. The influence of underground mining on pit slope stability was mainly discussed, and the self-stabilization of underg... Slope stability is of critical importance in the process of surface-underground mining combination. The influence of underground mining on pit slope stability was mainly discussed, and the self-stabilization of underground stopes was also studied. The random finite element method was used to analyze the probability of the rock mass stability degree of both pit slopes and underground stopes. Meanwhile, 3D elasto-plastic finite element method was used to research into the stress, strain and rock mass failure resulting from mining. The results of numerical simulation indicate that the mining of the underground test stope has certain influence on the stability of the pit slope, but the influence is not great. The safety factor of pit slope is decreased by 0.06, and the failure probability of the pit slope is increased by 1.84%. In addition, the strata yielding zone exists around the underground test stope. The results basically conform to the information coming from the field monitoring. 展开更多
关键词 surface-underground mining combination STABILITY RELIABILITY random finite element method (numerical simulation)
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Experimental and numerical studies on aluminum-stainless steel explosive cladding 被引量:10
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作者 ELANGO E SARAVANAN S RAGHUKANDAN K 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第6期1742-1753,共12页
In this study,the effect of varied loading ratio(mass of the explosive/mass of flyer plate)on the nature of interface,temperature and pressure developed in aluminum-steel explosive cladding is presented.Increase in th... In this study,the effect of varied loading ratio(mass of the explosive/mass of flyer plate)on the nature of interface,temperature and pressure developed in aluminum-steel explosive cladding is presented.Increase in the loading ratio,R,enhances the pressure developed,kinetic energy utilization and deformation work performed.Interfacial microstructures exhibit the formation of molten layer at few spots,owing to the increase in temperature beyond the melting point of parent alloy.The increase in temperature and the quantum of pressure developed were determined by numerical simulation performed in Ansys AUTODYN by employing smoothed particle hydrodynamics(SPH)method.The positioning of the experimental conditions on the weldability window is presented as well. 展开更多
关键词 explosive cladding dissimilar metals numerical simulation MICROSTRUCTURE weldability window
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Parameter fitting of constitutive model and FEM analysis of solder joint thermal cycle reliability for lead-free solder Sn-3.5Ag 被引量:1
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作者 周萍 胡炳亭 +1 位作者 周孑民 杨莺 《Journal of Central South University》 SCIE EI CAS 2009年第3期339-343,共5页
The experimental tests of tensile for lead-flee solder Sn-3.5Ag were performed for the general work temperatures range from 11 to 90 ℃ and strain rate range from 5 × 10^-5 to 2 × 10^-2s^-1, and its stress--... The experimental tests of tensile for lead-flee solder Sn-3.5Ag were performed for the general work temperatures range from 11 to 90 ℃ and strain rate range from 5 × 10^-5 to 2 × 10^-2s^-1, and its stress--strain curves were compared to those of solder Sn-37Pb. The parameters in Anand model for solder Sn-3.5Ag were fitted based on experimental data and nonlinear fitting method, and its validity was checked by means of experimental data. Furthermore, the Anand model was used in the FEM analysis to evaluate solder joint thermal cycle reliability. The results show that solder Sn-3.5Ag has a better creep resistance than solder Sn-37Pb. The maximum stress is located at the upper right comer of the outmost solder joint from the symmetric center, and thermal fatigue life is predicted to be 3.796 × 10^4 cycles under the calculated conditions. 展开更多
关键词 lead free solder Sn-3.5Ag alloy Sn-37Pb alloy constitutive model TENSILE FEM analysis thermal cycle reliability
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Modeling and analysis of cloud computing system survivability based on Bio-PEPA 被引量:1
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作者 Zhao Guosheng Ren Mengqi +1 位作者 Wang Jian Liao Yiwei 《Journal of Southeast University(English Edition)》 EI CAS 2018年第1期21-27,共7页
For the cloud computing system,combined wth the memory function and incomplete matching of the biological immune system,a formal modeling and analysis method of the cloud computing system survivability is proposed by ... For the cloud computing system,combined wth the memory function and incomplete matching of the biological immune system,a formal modeling and analysis method of the cloud computing system survivability is proposed by analyzing the survival situation of critical cloud services.First,on the basis of the SAIR(susceptible,active,infected,recovered)model,the SEIRS(susceptible,exposed,infected,recovered,susceptible)model and the vulnerability diffusion model of the distributed virtual system,the evolution state of the virus is divided into six types,and then the diffusion rules of the virus in the service domain of the cloud computing system and the propagation rules between service domains are analyzee.Finally,on the basis of Bio-PEPA(biological-performance evaluation process algebra),the formalized modeling of the survivability evolution of critical cloud services is made,and the SLIRAS(susceptible,latent,infected,recovered,antidotal,susceptible)model is obtained.Based on the stochastic simulation and the ODEs(ordinary differential equations)simulation of the Bio-PEPA model,the sensitivity parameters of the model are analyzed from three aspects,namely,the virus propagation speed of inter-domain,recovery ability and memory ability.The results showthat the proposed model has high approximate fitting degree to the actual cloud computing system,and it can well reflect the survivable change of the system. 展开更多
关键词 cloud computing system Bio-I>EPA(biologicalperformance evaluation process algebra) SURVIVABILITY stochastic simulation
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STUDY ON PRODUCTION SYSTEM OPERATION REGULARITY OF FULLY MECHANIZED SUBLEVEL CAVING MINING AND SEQUENTIAL OPERATION
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作者 李学忠 王新淮 陈永文 《Journal of Coal Science & Engineering(China)》 1998年第1期30-35,共6页
According to a lot of practical data in Liujialiang Mine and reliability theory and result of computer simulation, operation regularity of fully mechanized sublevel caving mining production system in the condition of ... According to a lot of practical data in Liujialiang Mine and reliability theory and result of computer simulation, operation regularity of fully mechanized sublevel caving mining production system in the condition of gently inclined complicated geological structure and production shortcomings are found out and reliability of system and output of the working face are predicted finally. 展开更多
关键词 fully mechanized sublevel caving mining face sequential operation computer simulation reliability theory
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Reservoir lithology stochastic simulation based on Markov random fields 被引量:2
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作者 梁玉汝 王志忠 郭建华 《Journal of Central South University》 SCIE EI CAS 2014年第9期3610-3616,共7页
Markov random fields(MRF) have potential for predicting and simulating petroleum reservoir facies more accurately from sample data such as logging, core data and seismic data because they can incorporate interclass re... Markov random fields(MRF) have potential for predicting and simulating petroleum reservoir facies more accurately from sample data such as logging, core data and seismic data because they can incorporate interclass relationships. While, many relative studies were based on Markov chain, not MRF, and using Markov chain model for 3D reservoir stochastic simulation has always been the difficulty in reservoir stochastic simulation. MRF was proposed to simulate type variables(for example lithofacies) in this work. Firstly, a Gibbs distribution was proposed to characterize reservoir heterogeneity for building 3-D(three-dimensional) MRF. Secondly, maximum likelihood approaches of model parameters on well data and training image were considered. Compared with the simulation results of MC(Markov chain), the MRF can better reflect the spatial distribution characteristics of sand body. 展开更多
关键词 stochastic modeling Markov random fields training image Monte Carlo simulation
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Reliability Improvements to Centrifugal Pump Performance in Conjunction with Inducers, CFD Comparative Study 被引量:1
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作者 Said A. F. Hawash Dalia M. S. EI Gazzar Mohamed A. EI Samanoudy 《Journal of Earth Science and Engineering》 2015年第5期296-305,共10页
In this research, centrifugal pump unit was analysed to study the effects of using inducers on its performance. Hydraulic tests were done to obtain the optimum hydraulic performance before and after using inducer. Two... In this research, centrifugal pump unit was analysed to study the effects of using inducers on its performance. Hydraulic tests were done to obtain the optimum hydraulic performance before and after using inducer. Two types of inducers were used in this work (axial, helical). For this purpose, a test rig was specially designed with a pump system to investigate the parameters under consideration. Plots (H-Q) curves, (B.P.-Q) curves and (q-Q) curves were used to show the effect of pump performance with and without inducers. The present study introduces a simulation of centrifugal pump performance in conjunction with inducers using CFD (Computational Fluid Dynamics), to compare it with experimentally observed values. The model investigates the impact of using inducers on the head and flow of the pump. The results of the CFD model and experimental are correlated well. Furthermore, the results help the decision makers of the pumps for future developments in pump performance assuring safe and reliable running condition of the water pumps. Also it may be used for more applications of larger head and flow pumps. 展开更多
关键词 Centrifugal pump axial helical inducers hydraulic performance CFD simulation NPSH.
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Several Problems about the Generalized Convexity 被引量:1
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作者 王治国 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第3期100-102,共3页
In this article,we will prove that,under the differential condition,the strict pseudo_convexity and Orgega_Rheinbold pseudo_convex are equivalent.What's more,we will discuss the relation between the r_convexity an... In this article,we will prove that,under the differential condition,the strict pseudo_convexity and Orgega_Rheinbold pseudo_convex are equivalent.What's more,we will discuss the relation between the r_convexity and the analog convexity. 展开更多
关键词 pseudo_convexity EQUIVALENCE r_convexity analog convexity
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Study on the random simulation times of mining engineering reliability
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作者 毕忠伟 丁德馨 张新华 《Journal of Coal Science & Engineering(China)》 2005年第2期13-15,共3页
The theory of Monte-Carlo simulation method is that the event happened probability was estimated by happened frequency in the experiments. So it is very im-portant to ascertain the times of simulation. The probability... The theory of Monte-Carlo simulation method is that the event happened probability was estimated by happened frequency in the experiments. So it is very im-portant to ascertain the times of simulation. The probability and statistic theory are used to determine the optimal simulation times through strict mathematic reasoning. The study of two cases is made to show the availability of the presented method, and some relative problems were discussed. 展开更多
关键词 mining engineering Monte-Carlo RELIABILITY random simulation
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Investigation on Promising Additives for Simultaneous Oxidation of NO and SO_2 in Flue Gas by Numerical Simulation 被引量:2
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作者 宋蔷 越光男 定方正毅 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第5期531-535,共5页
Mechanism analysis on simultaneous oxidation of NO and SO2 with additives was presented and numerical simulation was developed to investigate the performances of three additives on oxidation of NO and SO2. The simulat... Mechanism analysis on simultaneous oxidation of NO and SO2 with additives was presented and numerical simulation was developed to investigate the performances of three additives on oxidation of NO and SO2. The simulation result showed that reaction temperature, residence time, additive dose and NO concentration influence the oxidation process significantly. There exists an optimum reaction condition for each additive, n-C4H10 has the strongest ability to oxidize NO and SO2. 展开更多
关键词 ADDITIVE NO SO2 OXIDATION flue gas
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EVALUATION OF THE GEOLOGICAL RELIABILITY OF SURFACE MINING DEPOSIT
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作者 韩金炎 孙小彦 彭世济 《Journal of China University of Mining and Technology》 1994年第1期32-42,共11页
The optimal deeision theory and exploitation reliability of large scale mining area have been studied China since the late 1980’s. Researches have been earried out under the thought of mannature - machine system , an... The optimal deeision theory and exploitation reliability of large scale mining area have been studied China since the late 1980’s. Researches have been earried out under the thought of mannature - machine system , and eneouraging results have been obtained. The reliability evaluation of mining engineering ineludes the rellability exaluation of natural resources, mining technology and mine economics ete. And the geological reliability of deposit, as a natural condition, is the basis of all other evaiuation works. The paper summarizes the method for evaluating the geological reliaoility of deposit, diseusces the reliability of estimating methods for coal reserves and coai quality, evaiuates the natural resourees rellability of the Pit 1 of Antaibao Surface Coai Mine, Pingsuo, Shanxi Province.which was taken as a case study. 展开更多
关键词 deposit model reliability evaluation conditional simulation semi-variogram CROSSVALIDATION
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Reduced Expanding Load Method for Simulation-Based Structural System Reliability Analysis
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作者 远方 宋丽娜 方江生 《Transactions of Tianjin University》 EI CAS 2004年第2期142-145,共4页
The current situation and difficulties of the structural system reliability analysis are mentioned. Then on the basis of Monte Carlo method and computer simulation, a new analysis method reduced expanding load method ... The current situation and difficulties of the structural system reliability analysis are mentioned. Then on the basis of Monte Carlo method and computer simulation, a new analysis method reduced expanding load method (RELM) is presented, which can be used to solve structural reliability problems effectively and conveniently. In this method, the uncertainties of loads, structural material properties and dimensions can be fully considered. If the statistic parameters of stochastic variables are known, by using this method, the probability of failure can be estimated rather accurately. In contrast with traditional approaches,RELM method gives a much better understanding of structural failure frequency and its reliability index β is more meaningful.To illustrate this new idea, a specific example is given. 展开更多
关键词 reliability of structures computer simulation Monte Carlo method reduced expanding load method (RELM) probability paper
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Evaluation of gas production from multiple coal seams: A simulation study and economics 被引量:1
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作者 Yanting Wu Zhejun Pan +2 位作者 Dingyu Zhang Zhaohui Lu Luke D. Connell 《International Journal of Mining Science and Technology》 EI CSCD 2018年第3期359-371,共13页
Gas production from multiple coal seams has become common practice in many coal basins around the world. Although gas production rates are typically enhanced, the economic viability of such practice is not well studie... Gas production from multiple coal seams has become common practice in many coal basins around the world. Although gas production rates are typically enhanced, the economic viability of such practice is not well studied. In order to investigate the technical and economic feasibility of multiple coal seams production, reservoir simulation integrated with economics modelling was performed to study the effect of important reservoir properties of the secondary coal seam on production and economic performance using both vertical and horizontal wells. The results demonstrated that multiple seam gas production of using both vertical and horizontal wells have competitive advantage over single layer production under most scenarios. Gas content and permeability of the secondary coal seam are the most important reservoir properties that have impact on the economic feasibility of multiple seam gas production. The comparison of vertical well and horizontal well performance showed that horizontal well is more economically attractive for both single well and gas field. Moreover, wellhead price is the most sensitive to the economic performance, followed by operating costs and government subsidy. Although the results of reservoir simulation combined with economic analysis are subject to assumptions, multiple seam gas production is more likely to maintain profitability compared with single layer production. 展开更多
关键词 Multiple coal seam Production simulation Economic viability Sensitivity Coalbed methane
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