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Seismic effectiveness evaluation and optimized design of tie up method for securing museum collections
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作者 Wang Meng Yan Yi +3 位作者 Yang Weiguo Liu Pei Ge Jiaqi Ma Botao 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第3期741-763,共23页
To quantify the seismic effectiveness of the most commonly used fishing line tie up method for securing museum collections and optimize fixed strategies for exhibitions,shaking table tests of the seismic systems used ... To quantify the seismic effectiveness of the most commonly used fishing line tie up method for securing museum collections and optimize fixed strategies for exhibitions,shaking table tests of the seismic systems used for typical museum collection replicas have been carried out.The influence of body shape and fixed measure parameters on the seismic responses of replicas and the interaction behavior between replicas and fixed measures have been explored.Based on the results,seismic effectiveness evaluation indexes of the tie up method are proposed.Reasonable suggestions for fixed strategies are given,which provide a basis for the exhibition of delicate museum collections considering the principle of minimizing seismic responses and intervention.The analysis results show that a larger ratio of height of mass center to bottom diameter led to more intense rocking responses.Increasing the initial pretension of fishing lines was conducive to reducing the seismic responses and stress variation of the lines.Through comprehensive consideration of the interaction forces and effective securement,it is recommended to apply 20%of breaking stress as the initial pretension.For specific museum collections that cannot be effectively protected by the independent tie up method,an optimized strategy of a combination of fishing lines and fasteners is recommended. 展开更多
关键词 tie up method museum collections shaking table test seismic effectiveness optimized design
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Types and Optimization Paths Between Poverty Alleviation Effectiveness and Rural Revitalization:A Case Study of Hunan Province,China
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作者 TAN Xuelan WANG Zhenkai +1 位作者 AN Yue WANG Weilin 《Chinese Geographical Science》 SCIE CSCD 2023年第5期966-982,共17页
Exploring the synergy types and optimization paths between Poverty Alleviation Effectiveness and Rural Revitalization is necessary for achieving the two centenary goals.Taking poverty alleviation counties in Hunan Pro... Exploring the synergy types and optimization paths between Poverty Alleviation Effectiveness and Rural Revitalization is necessary for achieving the two centenary goals.Taking poverty alleviation counties in Hunan Province,China as an example,our study proposed an indicator to measure the synergistic development between Poverty Alleviation Effectiveness and Rural Revitalization using the multi-index integrated evaluation method.Then,the coupling types were classified based on both the proposed indicator and regional characteristics.Besides,the corresponding optimization path for each coupling type was proposed to promote the synergistic development of Poverty Alleviation and Rural Revitalization.Results are as follows:1)Lower synergy focused on the southwestern Hunan,while low synergy is widely distributed(such as the west,southwest,northwest,and midland).Moderate synergy is in the midland,such as Huaihua and Chenzhou cities.High synergy is distributed in Yongzhou,Huaihua,Xiangxi cities,etc.Besides,only Hecheng City belongs to the higher synergy.2)This paper proposes corresponding development paths for different development characteristics and main problems from multiple perspectives of the protection system,industrial planning,and rural market.Continuously consolidate and enhance the effectiveness of Poverty Alleviation and Rural Revitalization to achieve coupled and synergistic development of the two systems.Our research results can provide theoretical support for implementing Poverty Alleviation and Rural Revitalization in Hunan Province,China. 展开更多
关键词 Poverty Alleviation effectiveness Rural Revitalization coupling synergy type classification optimization path
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A hybrid machine learning optimization algorithm for multivariable pore pressure prediction
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作者 Song Deng Hao-Yu Pan +8 位作者 Hai-Ge Wang Shou-Kun Xu Xiao-Peng Yan Chao-Wei Li Ming-Guo Peng Hao-Ping Peng Lin Shi Meng Cui Fei Zhao 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期535-550,共16页
Pore pressure is essential data in drilling design,and its accurate prediction is necessary to ensure drilling safety and improve drilling efficiency.Traditional methods for predicting pore pressure are limited when f... Pore pressure is essential data in drilling design,and its accurate prediction is necessary to ensure drilling safety and improve drilling efficiency.Traditional methods for predicting pore pressure are limited when forming particular structures and lithology.In this paper,a machine learning algorithm and effective stress theorem are used to establish the transformation model between rock physical parameters and pore pressure.This study collects data from three wells.Well 1 had 881 data sets for model training,and Wells 2 and 3 had 538 and 464 data sets for model testing.In this paper,support vector machine(SVM),random forest(RF),extreme gradient boosting(XGB),and multilayer perceptron(MLP)are selected as the machine learning algorithms for pore pressure modeling.In addition,this paper uses the grey wolf optimization(GWO)algorithm,particle swarm optimization(PSO)algorithm,sparrow search algorithm(SSA),and bat algorithm(BA)to establish a hybrid machine learning optimization algorithm,and proposes an improved grey wolf optimization(IGWO)algorithm.The IGWO-MLP model obtained the minimum root mean square error(RMSE)by using the 5-fold cross-validation method for the training data.For the pore pressure data in Well 2 and Well 3,the coefficients of determination(R^(2))of SVM,RF,XGB,and MLP are 0.9930 and 0.9446,0.9943 and 0.9472,0.9945 and 0.9488,0.9949 and 0.9574.MLP achieves optimal performance on both training and test data,and the MLP model shows a high degree of generalization.It indicates that the IGWO-MLP is an excellent predictor of pore pressure and can be used to predict pore pressure. 展开更多
关键词 Pore pressure Grey wolf optimization Multilayer perceptron effective stress Machine learning
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Low rank optimization for efficient deep learning:making a balance between compact architecture and fast training
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作者 OU Xinwei CHEN Zhangxin +1 位作者 ZHU Ce LIU Yipeng 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第3期509-531,F0002,共24页
Deep neural networks(DNNs)have achieved great success in many data processing applications.However,high computational complexity and storage cost make deep learning difficult to be used on resource-constrained devices... Deep neural networks(DNNs)have achieved great success in many data processing applications.However,high computational complexity and storage cost make deep learning difficult to be used on resource-constrained devices,and it is not environmental-friendly with much power cost.In this paper,we focus on low-rank optimization for efficient deep learning techniques.In the space domain,DNNs are compressed by low rank approximation of the network parameters,which directly reduces the storage requirement with a smaller number of network parameters.In the time domain,the network parameters can be trained in a few subspaces,which enables efficient training for fast convergence.The model compression in the spatial domain is summarized into three categories as pre-train,pre-set,and compression-aware methods,respectively.With a series of integrable techniques discussed,such as sparse pruning,quantization,and entropy coding,we can ensemble them in an integration framework with lower computational complexity and storage.In addition to summary of recent technical advances,we have two findings for motivating future works.One is that the effective rank,derived from the Shannon entropy of the normalized singular values,outperforms other conventional sparse measures such as the?_1 norm for network compression.The other is a spatial and temporal balance for tensorized neural networks.For accelerating the training of tensorized neural networks,it is crucial to leverage redundancy for both model compression and subspace training. 展开更多
关键词 model compression subspace training effective rank low rank tensor optimization efficient deep learning
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Scheduling an Energy-Aware Parallel Machine System with Deteriorating and Learning Effects Considering Multiple Optimization Objectives and Stochastic Processing Time
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作者 Lei Wang Yuxin Qi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第4期325-339,共15页
Currently,energy conservation draws wide attention in industrial manufacturing systems.In recent years,many studies have aimed at saving energy consumption in the process of manufacturing and scheduling is regarded as... Currently,energy conservation draws wide attention in industrial manufacturing systems.In recent years,many studies have aimed at saving energy consumption in the process of manufacturing and scheduling is regarded as an effective approach.This paper puts forwards a multi-objective stochastic parallel machine scheduling problem with the consideration of deteriorating and learning effects.In it,the real processing time of jobs is calculated by using their processing speed and normal processing time.To describe this problem in a mathematical way,amultiobjective stochastic programming model aiming at realizing makespan and energy consumption minimization is formulated.Furthermore,we develop a multi-objective multi-verse optimization combined with a stochastic simulation method to deal with it.In this approach,the multi-verse optimization is adopted to find favorable solutions from the huge solution domain,while the stochastic simulation method is employed to assess them.By conducting comparison experiments on test problems,it can be verified that the developed approach has better performance in coping with the considered problem,compared to two classic multi-objective evolutionary algorithms. 展开更多
关键词 Energy consumption optimization parallel machine scheduling multi-objective optimization deteriorating and learning effects stochastic simulation
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An Uncertain Programming Model for Land Use Structure Optimization to Promote Effectiveness of Land Use Planning 被引量:4
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作者 LI Xin MA Xiaodong 《Chinese Geographical Science》 SCIE CSCD 2017年第6期974-988,共15页
Land use structure optimization(LUSO) is an important issue for land use planning. In order for land use planning to have reasonable flexibility, uncertain optimization should be applied for LUSO. In this paper, the r... Land use structure optimization(LUSO) is an important issue for land use planning. In order for land use planning to have reasonable flexibility, uncertain optimization should be applied for LUSO. In this paper, the researcher first expounded the uncertainties of LUSO. Based on this, an interval programming model was developed, of which interval variables were to hold land use uncertainties. To solve the model, a heuristics based on Genetic Algorithm was designed according to Pareto Optimum principle with a confidence interval under given significance level to represent LUSO result. Proposed method was applied to a real case of Yangzhou, an eastern city in China. The following conclusions were reached. 1) Different forms of uncertainties ranged from certainty to indeterminacy lay in the five steps of LUSO, indicating necessary need of comprehensive approach to quantify them. 2) With regards to trade-offs of conflicted objectives and preferences to uncertainties, our proposed model displayed good ability of making planning decision process transparent, therefore providing an effective tool for flexible land use planning compiling. 3) Under uncertain conditions, land use planning effectiveness can be primarily enhanced by flexible management with reserved space to percept and hold uncertainties in advance. 展开更多
关键词 土地利用规划 土地利用结构 确定性优化 规划模型 不确定性 区间变量 启发式算法 显著性水平
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A Chaotic Local Search-Based Particle Swarm Optimizer for Large-Scale Complex Wind Farm Layout Optimization 被引量:2
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作者 Zhenyu Lei Shangce Gao +2 位作者 Zhiming Zhang Haichuan Yang Haotian Li 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第5期1168-1180,共13页
Wind energy has been widely applied in power generation to alleviate climate problems.The wind turbine layout of a wind farm is a primary factor of impacting power conversion efficiency due to the wake effect that red... Wind energy has been widely applied in power generation to alleviate climate problems.The wind turbine layout of a wind farm is a primary factor of impacting power conversion efficiency due to the wake effect that reduces the power outputs of wind turbines located in downstream.Wind farm layout optimization(WFLO)aims to reduce the wake effect for maximizing the power outputs of the wind farm.Nevertheless,the wake effect among wind turbines increases significantly as the number of wind turbines increases in the wind farm,which severely affect power conversion efficiency.Conventional heuristic algorithms suffer from issues of low solution quality and local optimum for large-scale WFLO under complex wind scenarios.Thus,a chaotic local search-based genetic learning particle swarm optimizer(CGPSO)is proposed to optimize large-scale WFLO problems.CGPSO is tested on four larger-scale wind farms under four complex wind scenarios and compares with eight state-of-the-art algorithms.The experiment results indicate that CGPSO significantly outperforms its competitors in terms of performance,stability,and robustness.To be specific,a success and failure memories-based selection is proposed to choose a chaotic map for chaotic search local.It improves the solution quality.The parameter and search pattern of chaotic local search are also analyzed for WFLO problems. 展开更多
关键词 Chaotic local search(CLS) evolutionary computation genetic learning particle swarm optimization(PSO) wake effect wind farm layout optimization(WFLO)
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Support vector regression-based operational effectiveness evaluation approach to reconnaissance satellite system
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作者 HAN Chi XIONG Wei +1 位作者 XIONG Minghui LIU Zhen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第6期1626-1644,共19页
As one of the most important part of weapon system of systems(WSoS),quantitative evaluation of reconnaissance satellite system(RSS)is indispensable during its construction and application.Aiming at the problem of nonl... As one of the most important part of weapon system of systems(WSoS),quantitative evaluation of reconnaissance satellite system(RSS)is indispensable during its construction and application.Aiming at the problem of nonlinear effectiveness evaluation under small sample conditions,we propose an evaluation method based on support vector regression(SVR)to effectively address the defects of traditional methods.Considering the performance of SVR is influenced by the penalty factor,kernel type,and other parameters deeply,the improved grey wolf optimizer(IGWO)is employed for parameter optimization.In the proposed IGWO algorithm,the opposition-based learning strategy is adopted to increase the probability of avoiding the local optima,the mutation operator is used to escape from premature convergence and differential convergence factors are applied to increase the rate of convergence.Numerical experiments of 14 test functions validate the applicability of IGWO algorithm dealing with global optimization.The index system and evaluation method are constructed based on the characteristics of RSS.To validate the proposed IGWO-SVR evaluation method,eight benchmark data sets and combat simulation are employed to estimate the evaluation accuracy,convergence performance and computational complexity.According to the experimental results,the proposed method outperforms several prediction based evaluation methods,verifies the superiority and effectiveness in RSS operational effectiveness evaluation. 展开更多
关键词 reconnaissance satellite system(RSS) support vector regression(SVR) gray wolf optimizer opposition-based learning parameter optimization effectiveness evaluation
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A Method of Evaluating the Effectiveness of a Hydraulic Oscillator in Horizontal Wells
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作者 Zhen Zhong Yadong Li +1 位作者 Yuxuan Zhao Pengfei Ju 《Sound & Vibration》 EI 2023年第1期15-27,共13页
Bent-housing motor is the most widely used directional drilling tool,but it often encounters the problem of high friction when sliding drilling in horizontal wells.In this paper,a mathematical model is proposed to sim... Bent-housing motor is the most widely used directional drilling tool,but it often encounters the problem of high friction when sliding drilling in horizontal wells.In this paper,a mathematical model is proposed to simulate slide drilling with a friction reduction tool of axial vibration.A term called dynamic effective tractoring force(DETF)is defined and used to evaluate friction reduction effectiveness.The factors influencing the DETF are studied,and the tool placement optimization problem is investigated.The studyfinds that the drilling rate of penetration(ROP)can lower the DETF but does not change the trend of the DETF curve.To effectively work,the shock tool stiffness must be greater than some critical value.For the case study,the best oscillating frequency is within 15∼20 Hz.The reflection of the vibration at the bit boundary can intensify or weaken the friction reduction effec-tiveness,depending on the distance between the hydraulic oscillator and the bit.The optimal placement position corresponds to the plateau stage of the DETF curve.The reliability of the method is verified by thefield tests.The proposed method can provide a design and use guide to hydraulic oscillators and improve friction reduction effectiveness in horizontal wells. 展开更多
关键词 Hydraulic oscillator axial vibration friction reduction dynamic effective tractoring force placement optimization
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Modeling Anthrax with Optimal Control and Cost Effectiveness Analysis 被引量:1
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作者 Shaibu Osman Dominic Otoo Oluwole Daniel Makinde 《Applied Mathematics》 2020年第3期255-275,共21页
Anthrax is an infection caused by bacteria and it affects both human and animal populations. The disease can be categorized under zoonotic diseases and humans can contract infections through contact with infected anim... Anthrax is an infection caused by bacteria and it affects both human and animal populations. The disease can be categorized under zoonotic diseases and humans can contract infections through contact with infected animals, ingest contaminated dairy and animal products. In this paper, we developed a mathematical model for anthrax transmission dynamics in both human and animal populations with optimal control. The qualitative solution of the model behaviour was analyzed by determining Rhv, equilibrium points and sensitivity analysis. A vaccination class was incorporated into the model with waning immunity. Local and global stability of the model’s equilibria was found to be locally asymptotically stable whenever Rhv Rhv. It was revealed that reducing animal and human interaction rate, would decrease Rhv. We extended the model to optimal control in order to find the best control strategy in reducing anthrax infections. It showed that the effective strategy in combating the anthrax epidemics is vaccination of animals and prevention of humans. 展开更多
关键词 ANTHRAX Model STABILITY Analysis Sensitivity optimAL Control COST effectiveness
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The Optimization Study of General Education Practice Effect in Our Country 被引量:1
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作者 Liu Jie 《学术界》 CSSCI 北大核心 2013年第12期283-290,共8页
General education has become more and more attention.The culture has a more long-term and lasting contribution,so more and more colleges and universities have adopted a series of reform measures.Effect of the practice... General education has become more and more attention.The culture has a more long-term and lasting contribution,so more and more colleges and universities have adopted a series of reform measures.Effect of the practice of general education,however,still cannot satisfactory.In this paper,main factors affecting was analyzed on the basis of extensive research and questionnaire data analysis and targeted put forward the optimization effect of general education.It is important to make every effort to make the general education in China to achieve"Phoenix Nirvana". 展开更多
关键词 教育实践 优化 通识教育 影响因素 数据分析 调查问卷 大学
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Multi-Objective Bacterial Foraging Optimization Algorithm Based on Effective Area in Cognitive Emergency Communication Networks
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作者 Shibing Zhang Xue Ji +1 位作者 Lili Guo Zhihua Bao 《China Communications》 SCIE CSCD 2021年第12期252-269,共18页
Cognitive emergency communication net-works can meet the requirements of large capac-ity,high density and low delay in emergency com-munications.This paper analyzes the properties of emergency users in cognitive emerg... Cognitive emergency communication net-works can meet the requirements of large capac-ity,high density and low delay in emergency com-munications.This paper analyzes the properties of emergency users in cognitive emergency communi-cation networks,designs a multi-objective optimiza-tion and proposes a novel multi-objective bacterial foraging optimization algorithm based on effective area(MOBFO-EA)to maximize the transmission rate while maximizing the lifecycle of the network.In the algorithm,the effective area is proposed to prevent the algorithm from falling into a local optimum,and the diversity and uniformity of the Pareto-optimal solu-tions distributed in the effective area are used to eval-uate the optimization algorithm.Then,the dynamic preservation is used to enhance the competitiveness of excellent individuals and the uniformity and diversity of the Pareto-optimal solutions in the effective area.Finally,the adaptive step size,adaptive moving direc-tion and inertial weight are used to shorten the search time of bacteria and accelerate the optimization con-vergence.The simulation results show that the pro-posed MOBFO-EA algorithm improves the efficiency of the Pareto-optimal solutions by approximately 55%compared with the MOPSO algorithm and by approx-imately 60%compared with the MOBFO algorithm and has the fastest and smoothest convergence. 展开更多
关键词 wireless communications emergency communications cognitive radio networks multi-objective optimization algorithm effective areas self-adaption
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System optimization-oriented spare parts dynamic configuration model for multi-echelon multi-indenture system 被引量:9
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作者 Minzhi Ruan Hua Li Jian Fu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第5期923-933,共11页
In order to optimize the spares configuration project at different stages during the life cycle, the factor of time is considered to relax the assumption of the spares steady demand in multi-echelon technique for reco... In order to optimize the spares configuration project at different stages during the life cycle, the factor of time is considered to relax the assumption of the spares steady demand in multi-echelon technique for recoverable item control (METRIC) theory. According to the method of systems analysis, the dynamic palm theorem is introduced to establish the prediction model of the spares demand rate, and its main influence factors are analyzed, based on which, the spares support effectiveness evaluation index system is studied, and the system optimization-oriented spares dynamic configuration method for multi-echelon multi-indenture system is proposed. Through the analysis of the optimization algorithm, the layered marginal algorithm is designed to improve the model calculation efficiency. In a given example, the multi-stage spares configuration project during its life cycle is gotten, the research result conforms to the actual status, and it can provide a new way for the spares dynamic optimization. 展开更多
关键词 system optimization spare parts dynamic demand support effectiveness multi-echelon multi-indenture layered marginal algorithm
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Seepage safety monitoring model for an earth rock dam under influence of high-impact typhoons based on particle swarm optimization algorithm 被引量:6
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作者 Yan Xiang Shu-yan Fu +2 位作者 Kai Zhu Hui Yuan Zhi-yuan Fang 《Water Science and Engineering》 EI CAS CSCD 2017年第1期70-77,共8页
Extreme hydrological events induced by typhoons in reservoir areas have presented severe challenges to the safe operation of hydraulic structures. Based on analysis of the seepage characteristics of an earth rock dam,... Extreme hydrological events induced by typhoons in reservoir areas have presented severe challenges to the safe operation of hydraulic structures. Based on analysis of the seepage characteristics of an earth rock dam, a novel seepage safety monitoring model was constructed in this study. The nonlinear influence processes of the antecedent reservoir water level and rainfall were assumed to follow normal distributions. The particle swarm optimization (PSO) algorithm was used to optimize the model parameters so as to raise the fitting accuracy. In addition, a mutation factor was introduced to simulate the sudden increase in the piezometric level induced by short-duration heavy rainfall and the possible historical extreme reservoir water level during a typhoon. In order to verify the efficacy of this model, the earth rock dam of the Siminghu Reservoir was used as an example. The piezometric level at the SW1-2 measuring point during Typhoon Fitow in 2013 was fitted with the present model, and a corresponding theoretical expression was established. Comparison of fitting results of the piezometric level obtained from the present statistical model and traditional statistical model with monitored values during the typhoon shows that the present model has a higher fitting accuracy and can simulate the uprush feature of the seepage pressure during the typhoon perfectly. 展开更多
关键词 Monitoring model Particle swarm optimization algorithm Earth rock dam Lagging effect TYPHOON Seepage pressure Mutation factor Piezometric level
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Optimization of reluctance accelerator efficiency by an improved discharging circuit 被引量:4
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作者 Hui-min Deng Yu Wang +1 位作者 Fa-long Lu Zhong-ming Yan 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2020年第3期662-667,共6页
In this paper,an improved discharging circuit was proposed to quicken the decay of the current in the drive coil in a reluctance accelerator when the armature reaches the center of the coil.The aim of this is to preve... In this paper,an improved discharging circuit was proposed to quicken the decay of the current in the drive coil in a reluctance accelerator when the armature reaches the center of the coil.The aim of this is to prevent the suck-back effect caused by the residual current in drive coil.The method is adding a reverse charging branch with a small capacitor in the traditional pulsed discharging circuit.The results under the traditional circuit and the improved circuit were compared in a simulation.The experiment then verified the simulations and they had good agreement.Simulation and experiment both demonstrated the improved circuit can effectively prevent the suck-back effect and increase the efficiency.At the voltage of 800 V,an efficiency increase of 36.34% was obtained. 展开更多
关键词 Reluctance accelerator Suck-back effect Discharging circuit Current decay Efficiency optimization
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Improved Car-Following Model Considering Modified Backward Optimal Velocity and Velocity Difference with Backward-Looking Effect 被引量:2
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作者 Md. Anowar Hossain K. M. Ariful Kabir Jun Tanimoto 《Journal of Applied Mathematics and Physics》 2021年第2期242-259,共18页
In this paper, a new traffic flow model called the forward-backward velocity difference (FBVD) model based on the full velocity difference model is proposed to investigate the backward-looking effect by applying a mod... In this paper, a new traffic flow model called the forward-backward velocity difference (FBVD) model based on the full velocity difference model is proposed to investigate the backward-looking effect by applying a modified backward optimal velocity using generalized backward maximum speed. The FBVD model belongs to the family of microscopic models that consider spatiotemporally continuous formulations. Neutral stability conditions of the discrete car-following model are derived using the linear stability theory. The stability analysis results prove that the modified backward optimal velocity has a significant positive effect in stabilizing the traffic flow. Through nonlinear analysis, a kink-antikink solution is derived from the modified Korteweg-de Vries equation of the FBVD model to explain traffic congestion of the model. The validity of this theoretical model is checked using numerical results, according to which traffic jams were found to have been significantly diminished by the introduction of the modified backward optimal velocity. 展开更多
关键词 Realistic Backward optimal Velocity Standerized Backward Maximum Speed Honked effect Backward-Looking effect Car-Following Modelling
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STUDY ON THE OPTIMIZATION OF TRANSPORT CONTROL POLICY IN COMMUNICATION NETWORK 被引量:1
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作者 Fan Shuyan Han Weizhan Lu Ran 《Journal of Electronics(China)》 2010年第2期261-266,共6页
In communication networks with policy-based Transport Control on-Demand (TCoD) function,the transport control policies play a great impact on the network effectiveness. To evaluate and optimize the transport policies ... In communication networks with policy-based Transport Control on-Demand (TCoD) function,the transport control policies play a great impact on the network effectiveness. To evaluate and optimize the transport policies in communication network,a policy-based TCoD network model is given and a comprehensive evaluation index system of the network effectiveness is put forward from both network application and handling mechanism perspectives. A TCoD network prototype system based on Asynchronous Transfer Mode/Multi-Protocol Label Switching (ATM/MPLS) is introduced and some experiments are performed on it. The prototype system is evaluated and analyzed with the comprehensive evaluation index system. The results show that the index system can be used to judge whether the communication network can meet the application requirements or not,and can provide references for the optimization of the transport policies so as to improve the communication network effectiveness. 展开更多
关键词 Communication network Comprehensive evaluation index system Network Application effectiveness (NAE) Transport Control on-Demand (TCoD) Policy optimization
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Substructure design optimization and nonlinear responses control analysis of the mega-sub controlled structural system (MSCSS) under earthquake action 被引量:1
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作者 Mustapha Abdulhadi Zhang Xun′an +1 位作者 Buqiao Fan Muhammad Moman 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2021年第3期687-704,共18页
The newly proposed mega sub-controlled structure system(MSCSS)and related studies have drawn the attention of civil engineers for practice in improving the performance and enhancing the structural effectiveness of meg... The newly proposed mega sub-controlled structure system(MSCSS)and related studies have drawn the attention of civil engineers for practice in improving the performance and enhancing the structural effectiveness of mega frame structures.However,there is still a need for improvement to its basic structural arrangement.In this project,an advanced,reasonable arrangement of mega sub-controlled structure models,composed of three mega stories with different numbers and arrangements of substructures,are designed to investigate the control performance of the models and obtain the optimal model configuration(model with minimum acceleration and displacement responses)under strong earthquake excitation.In addition,the dynamic parameters that affect the performance effectiveness of the optimal model of MSCSS are studied and discussed.The area of the relative stiffness ratio RD,with different mass ratio MR,within which the acceleration and displacement of the optimal model of MSCSS reaches its optimum(minimum)value is considered as an optimum region.It serves as a useful tool in practical engineering design.The study demonstrates that the proposed MSCSS configuration can efficiently control the displacement and acceleration of high rise buildings.In addition,some analytical guidelines are provided for selecting the control parameters of the structure. 展开更多
关键词 mega sub-controlled structure system(MSCSS) optimal model viscous damper dynamic parameters control effectiveness response control rubber bearing
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Topology and Shape Optimization of 2-D and 3-D Micro-ArchitecturedThermoelastic Metamaterials Using a Parametric Level Set Method 被引量:1
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作者 Ellie Vineyard Xin-Lin Gao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第6期819-854,共36页
2-D and 3-D micro-architectured multiphase thermoelastic metamaterials are designed and analyzed using a parametric level set method for topology optimization and the finite element method.An asymptotic homogenization... 2-D and 3-D micro-architectured multiphase thermoelastic metamaterials are designed and analyzed using a parametric level set method for topology optimization and the finite element method.An asymptotic homogenization approach is employed to obtain the effective thermoelastic properties of the multiphase metamaterials.Theε-constraint multi-objective optimization method is adopted in the formulation.The coefficient of thermal expansion(CTE)and Poisson’s ratio(PR)are chosen as two objective functions,with the CTE optimized and the PR treated as a constraint.The optimization problems are solved by using the method of moving asymptotes.Effective isotropic and anisotropic CTEs and stiffness constants are obtained for the topologically optimized metamaterials with prescribed values of PR under the constraints of specified effective bulk modulus,volume fractions and material symmetry.Two solid materials along with one additional void phase are involved in each of the 2-D and 3-D optimal design examples.The numerical results reveal that the newly proposed approach can integrate shape and topology optimizations and lead to optimal microstructures with distinct topological boundaries.The current method can topologically optimize metamaterials with a positive,negative or zero CTE and a positive,negative or zero Poisson’s ratio. 展开更多
关键词 Topology optimization thermoelastic metamaterial level set method sensitivity analysis Poisson’s ratio coefficient of thermal expansion effective elastic properties
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Dominating factors on well productivity and development strategies optimization in Weiyuan shale gas play, Sichuan Basin, SW China 被引量:4
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作者 MA Xinhua LI Xizhe +7 位作者 LIANG Feng WAN Yujin SHI Qiang WANG Yonghui ZHANG Xiaowei CHE Mingguang GUO Wei GUO Wei 《Petroleum Exploration and Development》 2020年第3期594-602,共9页
Weiyuan shale gas play is characterized by thin high-quality reservoir thickness,big horizontal stress difference,and big productivity differences between wells.Based on integrated evaluation of shale gas reservoir ge... Weiyuan shale gas play is characterized by thin high-quality reservoir thickness,big horizontal stress difference,and big productivity differences between wells.Based on integrated evaluation of shale gas reservoir geology and well logging interpretation of more than 20 appraisal wells,a correlation was built between the single well test production rate and the high-quality reservoir length drilled in the horizontal wells,high-quality reservoir thickness and the stimulation treatment parameters in over 100 horizontal wells,the dominating factors on horizontal well productivity were found out,and optimized development strategies were proposed.The results show that the deployed reserves of high-quality reservoir are the dominating factors on horizontal well productivity.In other words,the shale gas well productivity is controlled by the thickness of the high-quality reservoir,the high-quality reservoir drilling length and the effectiveness of stimulation.Based on the above understanding,the development strategies in Weiyuan shale gas play are optimized as follows:(1)The target of horizontal wells is located in the middle and lower parts of Longyi 11(Wei202 area)and Longyi 11(Wei204 area).(2)Producing wells are drilled in priority in the surrounding areas of Weiyuan county with thick high-quality reservoir.(3)A medium to high intensity stimulation is adopted.After the implementation of these strategies,both the production rate and the estimated ultimate recovery(EUR)of individual shale gas wells have increased substantially. 展开更多
关键词 Weiyuan shale gas play dominating factors of well productivity deployed reserves of high-quality reservoir thickness of high-quality reservoir high-quality reservoir drilling length effectiveness of stimulation development strategies optimization
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