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    题名 作者 年代 出处 被引量
1A NEW METHOD FOR STRUCTURAL TOPOLOGICAL OPTIMIZATION BASED ON THE CONCEPT OF INDEPENDENT CONTINUOUS VARIABLES AND SMOOTH MODEL显示文摘A concept of the independent-continuous topological variable is pro-posed to establish its corresponding smooth model of structural topological optimiza-tion. The method can overcome difficulties that are encountered in conventionalmodels and algorithms for the optimization of the structural topology. Its appli-cation to truss topological optimization with stress and displacement constraints issatisfactory, with convergence faster than that of sectional optimizations.隋允康 杨德庆 1998Acta Mechanica Sinica1998,14,2:78
2Homogenization of temperature field and temperature gradient field显示文摘The homogenization of temperature field and temperature gradient field are very important for many devices, systems and equipments, such as satellites and electronic devices. This paper discusses the distribution optimization of the limited high conductivity material with the simulated annealing algorithm to homogenize the temperature field in a two-dimensional heat conduction problem. At the same time, the temperature gradient field is homogenized with the bionic optimization method. The results show that the two optimization targets are consistent to some extent, while the bionic optimization method could save much computing time. In addition, there are threshold values for the amount of high conductivity material and the ratio of the high conductivity to the low conductivity beyond which further increasing these values brings very little improvement on the homogenization of temperature field and temperature gradient field.CHENG XueTao XU XiangHua LIANG XinGang 2009Science China(Technological Sciences)2009,52,10:35
3Optimization of the head shape of the CRH3 high speed train显示文摘Aiming at optimizing the head shape of the CRH3 high speed train, an efficient optimization approach is proposed. The CFD analysis by solving Navier-Stokes equations is coupled with optimization calculation based on the multi-objective genetic algorithm, meanwhile the arbitrary shape deformation technique (ASD) is also introduced into the design flow, which greatly shortens the time consumption for geometry regeneration and flow field remeshing. As a result, the efficiency of the optimization calculation is highly improved. Statistical analysis is done to the designs in the design space, and the correlation between the design variables and the objective is studied to find out the key variables that most affect the objective. Response surface analysis is also performed to get the nonlinear relationship between the key design variables and the objective with the Kriging algorithm. Finally, after the optimization, an aerodynamic performance comparison between the optimal shape and the original shape reveals that the original shape of CRH3 high speed train owns a very stable aerodynamic performance and can be trustingly used in industry.SUN ZhenXu1, SONG JingJing1 & AN YiRan1 College of Engineering, State Key Laboratory for Turbulence and Complex Systems, Peking University, Beijing 100871, China 2010Science China(Technological Sciences)2010,53,12:35
4A New Evolutionary Algorithm for Function Optimization显示文摘A new algorithm based on genetic algorithm(GA) is developed for solving function optimization problems with inequality constraints. This algorithm has been used to a series of standard test problems and exhibited good performance. The computation results show that its generality, precision, robustness, simplicity and performance are all satisfactory.GUO Tao, KANG Li shan State Key Laboratory of Software Engineering, Wuhan University,Wuhan 430072, China 1999Wuhan University Journal of Natural Sciences1999,4,4:37
5A Review on Swarm Intelligence and Evolutionary Algorithms for Solving Flexible Job Shop Scheduling Problems显示文摘Flexible job shop scheduling problems(FJSP)have received much attention from academia and industry for many years.Due to their exponential complexity,swarm intelligence(SI)and evolutionary algorithms(EA)are developed,employed and improved for solving them.More than 60%of the publications are related to SI and EA.This paper intents to give a comprehensive literature review of SI and EA for solving FJSP.First,the mathematical model of FJSP is presented and the constraints in applications are summarized.Then,the encoding and decoding strategies for connecting the problem and algorithms are reviewed.The strategies for initializing algorithms?population and local search operators for improving convergence performance are summarized.Next,one classical hybrid genetic algorithm(GA)and one newest imperialist competitive algorithm(ICA)with variables neighborhood search(VNS)for solving FJSP are presented.Finally,we summarize,discus and analyze the status of SI and EA for solving FJSP and give insight into future research directions.Kaizhou Gao Zhiguang Cao Le Zhang Zhenghua Chen Yuyan Han Quanke Pan 2019IEEE/CAA Journal of Automatica Sinica2019,6,4:32
6基于跳距与改进粒子群算法的DV-Hop定位算法显示文摘针对DV-Hop定位算法定位精度不高的问题,提出一种带改进的权重平均每跳距离与改进的粒子群算法以改进经典DV-Hop算法。一方面,提出跳距误差与估计距离误差的加权平均值,修正原始的平均每跳距离。另一方面,采用分段的指数、对数递减权重改进粒子群的权重;同时,结合人工鱼群位置更新的优点来改进粒子群算法的位置更新。用改进的粒子群算法求解未知节点坐标,以提高定位精度。实验仿真表明,该算法的定位精度和稳定性与其他算法相比有明显的改善。范时平 罗丹 刘艳林 2016传感技术学报2016,29,9:27
7Self-tuning virtual synchronous generator control for improving frequency stability in autonomous photovoltaic-diesel microgrids显示文摘This paper investigates the use of a virtual synchronous generator(VSG) to improve frequency stability in an autonomous photovoltaic-diesel microgrid with energy storage. VSG control is designed to emulate inertial response and damping power via power injection from/to the energy storage system. The effect of a VSG with constant parameters(CP-VSG) on the system frequency is analyzed. Based on the case study, self-tuning algorithms are used to search for optimal parameters during the operation of the VSG in order to minimize the amplitude and rate of change of the frequency variations. The performances of the proposed self-tuning(ST)-VSG, the frequency droop method, and the CP-VSG are evaluated by comparing their effects on attenuating frequency variationsunder load variations. For both simulated and experimental cases, the ST-VSG was found to be more efficient than the other two methods in improving frequency stability.Rongliang SHI Xing ZHANG Chao HU Haizhen XU Jun GU Wei CAO 2018Journal of Modern Power Systems and Clean Energy2018,6,3:27
8Island partition of the distribution system with distributed generation显示文摘In this paper, a novel optimum island partition model based on Tree Knapsack Problem (TKP) is presented for the distribution system integrated with distributed generation (DG), and a Depth-first Dynamic Programming Algorithm (DPA) is used to solve this model. With the considerations of the load priority, controlled/uncontrolled loads, and the constraints of power balance, voltage and equipment capacity, the model can meet the practical engineering requirements very well. The island partition problem of the distribution system integrated with multiple DGs is first decomposed into multiple TKPs, each of which is solved by DPA respectively. Then, the initial optimum island partition scheme is gained through an island combination procedure, and the final island partition scheme is obtained after feasibility checking and adjustment. Since the algorithm proposed owns the advantages of strong theoretical foundation and low computational complexity, it can find the approximate optimal solution within a limited time. The results of examples demonstrate the validity of the new model and algorithm.WANG XuDong & LIN JiKeng* Key laboratory of Power System Simulation and Control of Ministry of Education, Tianjin University, Tianjin 300072, China 2010Science China(Technological Sciences)2010,53,11:21
9Eavesdropping in a quantum secret sharing protocol based on Grover algorithm and its solution显示文摘A detailed analysis has showed that the quantum secret sharing protocol based on the Grover algorithm (Phys Rev A, 2003, 68: 022306) is insecure. A dishonest receiver may obtain the full information without being detected. A quantum secret-sharing protocol is presents here, which mends the security loophole of the original secret-sharing protocol, and doubles the information capacity.HAO Liang1, LI JunLin1 & LONG GuiLu1,2 1Key Laboratory for Atomic and Molecular NanoSciences and Department of Physics, Tsinghua University, Beijing 100084, China 2Tsinghua National Laboratory for Information Science and Technology, Beijing 100084, China 2010Science China(Physics,Mechanics & Astronomy)2010,53,3:20
10基于相对增益和改进粒子群算法的PSS与直流调制协调策略显示文摘现有电力系统稳定器(power system stabilizer,PSS)和直流调制多使用本地信号作为控制器反馈输入信号,控制器间的交互作用可能降低甚至破坏系统稳定性。提出了一种基于广域测量信号的PSS与直流调制协调策略,首先通过留数法选择对于振荡模态可观性较强的广域信号作为阻尼控制器备选反馈信号;其次通过相对增益方法选择使PSS和直流调制交互影响最小的备选信号作为最佳反馈信号;而后设计分散控制器,并运用基于混沌和差分进化的混合粒子群优化算法对PSS和直流调制控制器参数进行协调优化。最后,通过EPRI 36节点系统仿真验证了协调策略的正确性和有效性。王曦 李兴源 赵睿 2014中国电机工程学报2014,34,34:17
11Frequency modulated weak signal detection based on stochastic resonance and genetic algorithm显示文摘Stochastic resonance system is subject to the restriction of small frequency parameter in weak signal detection,in order to solve this problem,a frequency modulated weak signal detection method based on stochastic resonance and genetic algorithm is presented in this paper. The frequency limit of stochastic resonance is eliminated by introducing carrier signal,which is multiplied with the measured signal to be injected in the stochastic resonance system,meanwhile,using genetic algorithm to optimize the carrier signal frequency,which determine the generated difference-frequency signal in the lowfrequency range,so as to achieve the stochastic resonance weak signal detection. Results showthat the proposed method is feasible and effective,which can significantly improve the output SNR of stochastic resonance,in addition,the system has the better self-adaptability,according to the operation result and output phenomenon,the unknown frequency of the signal to be measured can be obtained,so as to realize the weak signal detection of arbitrary frequency.XING Hongyan LU Chunxia ZHANG Qiang 2016Instrumentation2016,3,1:16
12Gastrointestinal stromal tumor of the stomach:How to manage?显示文摘Gastrointestinal stromal tumor (GIST) is one of the most common malignant mesenchymal tumors of the stomach. Prognosis of this disease is related to tumor size and mitotic activity and early diagnosis is the only way to improve it.Diagnosis of GIST always requires histological and immunohistochemical confirmation as no imaging modalities can diagnose it conclusively.Endoscopic forceps biopsy results are frequently negative. Endoscopic ultrasound-guided fine needle asp- iration (EUS-FNA) is a technique which allows tissue samples to be obtained with minimal risks and is accurate in the diagnosis of GIST. From the point of view of the endoscopist, aggressive use of EUS-FNA is the only promising way to allow early diagnosis and early treatment of this disease.Kazuya Akahoshi Masafumi Oya 2010World Journal of Gastrointestinal Endoscopy2010,2,8:16
13Application of several optimization techniques for estimating TBM advance rate in granitic rocks显示文摘This study aims to develop several optimization techniques for predicting advance rate of tunnel boring machine(TBM)in different weathered zones of granite.For this purpose,extensive field and laboratory studies have been conducted along the 12,649 m of the Pahang-Selangor raw water transfer tunnel in Malaysia.Rock properties consisting of uniaxial compressive strength(UCS),Brazilian tensile strength(BTS),rock mass rating(RMR),rock quality designation(RQD),quartz content(q)and weathered zone as well as machine specifications including thrust force and revolution per minute(RPM)were measured to establish comprehensive datasets for optimization.Accordingly,to estimate the advance rate of TBM,two new hybrid optimization techniques,i.e.an artificial neural network(ANN)combined with both imperialist competitive algorithm(ICA)and particle swarm optimization(PSO),were developed for mechanical tunneling in granitic rocks.Further,the new hybrid optimization techniques were compared and the best one was chosen among them to be used for practice.To evaluate the accuracy of the proposed models for both testing and training datasets,various statistical indices including coefficient of determination(R^2),root mean square error(RMSE)and variance account for(VAF)were utilized herein.The values of R^2,RMSE,and VAF ranged in 0.939-0.961,0.022-0.036,and 93.899-96.145,respectively,with the PSO-ANN hybrid technique demonstrating the best performance.It is concluded that both the optimization techniques,i.e.PSO-ANN and ICA-ANN,could be utilized for predicting the advance rate of TBMs;however,the PSO-ANN technique is superior.Danial Jahed Armaghani Mohammadreza Koopialipoor Aminaton Marto Saffet Yagiz 2019Journal of Rock Mechanics and Geotechnical Engineering2019,11,4:15
14On Improved DV-Hop Localization Algorithm for Accurate Node Localization in Wireless Sensor Networks显示文摘Node Localization is a fundamental issue for many critical applications in Wireless sensor networks(WSNs). Traditional DV-Hop localization algorithm and corresponding improved ones still cannot provide sufficient localization accuracy in such WSNs. To ensure accurate localization, this paper proposes an improved Distancevector-Hop(DV-Hop) localization algorithm. Under such an algorithm, we determine a corrected average hopdistance of beacon nodes by employing the differences between actual and estimated distance among beacon nodes in WSNs. We propose a probability information based selective strategy for the selection of beacon nodes.Based on these selected beacon nodes, we adopt a two dimensional hyperbolic function to predict the locations of unknown nodes. Simulation results are provided to illustrate the localization accuracy of our algorithm compared with traditional DV-Hop algorithm and its two improved algorithms in WSNs.SHEN Shikai YANG Bin QIAN Kaiguo SHE Yumei WANG Wu 2019Chinese Journal of Electronics2019,28,3:15
15Multi-robot path planning based on a deep reinforcement learning DQN algorithm显示文摘The unmanned warehouse dispatching system of the‘goods to people’model uses a structure mainly based on a handling robot,which saves considerable manpower and improves the efficiency of the warehouse picking operation.However,the optimal performance of the scheduling system algorithm has high requirements.This study uses a deep Q-network(DQN)algorithm in a deep reinforcement learning algorithm,which combines the Q-learning algorithm,an empirical playback mechanism,and the volume-based technology of productive neural networks to generate target Q-values to solve the problem of multi-robot path planning.The aim of the Q-learning algorithm in deep reinforcement learning is to address two shortcomings of the robot path-planning problem:slow convergence and excessive randomness.Preceding the start of the algorithmic process,prior knowledge and prior rules are used to improve the DQN algorithm.Simulation results show that the improved DQN algorithm converges faster than the classic deep reinforcement learning algorithm and can more quickly learn the solutions to path-planning problems.This improves the efficiency of multi-robot path planning.Yang Yang Li Juntao Peng Lingling 2020CAAI Transactions on Intelligence Technology2020,5,3:15
16Multiple-Step Predictive Control for Offshore Structures显示文摘—Ocean wave propagation is slow,visible and measurable,so a wave theory can be used to approxi-mately predict the imminnent wave force on an offshore structure based on measured,real-time wave elevation nearthe structure.This predictability suggests the development of a more efficient algorithm,than those that have beendeveloped for structures under wind and seismic loads,for the active vibration control of offshore structures.Thepresent study delveops a mutiple-step predictive optimal control(MPOC)algorithm that accounts for multiple-step external loading in the determibation of optimal control forces.The control efficiency of the newly developedMPOC algorithm has been investigated under both regular(single-frequency)and irregular(multiple-frequency)wave loads,and compared with that of two other well-known optimal control algorithms:classical linear optimalcontrol(CLOC)and instantaneou optimal control(IOC).李华军 Sau-Lon JAMES HU 1999China Ocean Engineering1999,14,3:14
17Path planning in uncertain environment by using firefly algorithm显示文摘Autonomous mobile robot navigation is one of the most emerging areas of research by using swarm intelligence. Path planning and obstacle avoidance are most researched current topics like navigational challenges for mobile robot. The paper presents application and implementation of Firefly Algorithm(FA)for Mobile Robot Navigation(MRN) in uncertain environment. The uncertainty is defined over the changing environmental condition from static to dynamic. The attraction of one firefly towards the other firefly due to variation of their brightness is the key concept of the proposed study. The proposed controller efficiently explores the environment and improves the global search in less number of iterations and hence it can be easily implemented for real time obstacle avoidance especially for dynamic environment. It solves the challenges of navigation, minimizes the computational calculations, and avoids random moving of fireflies. The performance of proposed controller is better in terms of path optimality when compared to other intelligent navigational approaches.B.K.Patle Anish Pandey A.Jagadeesh D.R.Parhi 2018Defence Technology(防务技术)2018,14,6:14
18Investigation on optimization design of equivalent water depth truncated mooring system显示文摘The oil industry is now increasingly concentrating their efforts and activities in connection with de- veloping fields in deeper waters, ranging typically from 500 m to 3000 m worldwide. However, the modeling of a full-depth system has become difficult presently; no tank facility is sufficiently large to perform the testing of a complete FPS with compliant mooring in 1000 m to 3000 m depth, within rea- sonable limits of model scale. Until recently, the most feasible procedure to meet this challenge seems to be the so-called 'hybrid model testing technique'. To implement this technique, the first and im- portant step is to design the equivalent water depth truncated mooring system. In this work, the opti- mization design of the equivalent water depth truncated mooring system in hybrid model testing for deep sea platforms is investigated. During the research, the similarity of static characteristics between the truncated and full depth system is mainly considered. The optimization mathematical model for the equivalent water depth truncated system design is set up by using the similarity in numerical value of the static characteristics between the truncated system and the full depth one as the objective function. The dynamic characteristic difference between the truncated and full depth mooring system can be minished by selecting proper design rule. To calculate the static characteristics of the mooring system, the fourth order Runge-Kutta method is used to solve the static equilibrium equation of the single mooring line. After the static characteristic of the single mooring line is calculated, the static charac- teristic of the whole mooring system is calculated with Lagrange numerical interpolation method. The mooring line material database is established and the standard material name and the diameter of the mooring line are selected as the primary key. The improved simulated annealing algorithm for continual & discrete variables and the improved complex algorithm for discrete variables are employed to per- form the optimization calculation. The C++ programming language is used to develop the computer program according to the object-oriented programming idea. To perform the optimization calculation with the two algorithms mentioned above respectively and the better result is selected as the final one. To examine the developed program, an example of equivalent water depth truncated mooring system optimum design calculation on a 100,000-t, turret mooring FPSO in water depth of 320 m are performed to obtain the conformation parameters of the truncated mooring system, in which the truncated water depth is 160 m. The model test under some typical environment conditions are performed for both the truncated and the full depth system with model scale factor λ=80. After comparing the corresponding results from the test of the truncated system with those from the full depth system test, it’s found that the truncated mooring system design in this work is successful.ZHANG HuoMing SUN ZhiLin YANG JianMin GAO MingZheng 2009Science China(Physics,Mechanics & Astronomy)2009,52,2:14
19Multiligament knee injuries with associated tibial plateau fractures: A report of two cases显示文摘The management of a combination of fracture and multiligament knee injury(MKI) in traumatic knee injury remains controversial, and there are evolving treatment recommendations. Currently, there are no studies focusing on older adult patients with MKI's in combination with tibia fractures. As a result, there is no well-established treatment algorithm for older adult patients with these complex injuries. We report two cases of MKI's with concomitant fractures in patients fifty years of age or older. Both patients were treated surgically for their associated tibial plateau fractures, but were managed with conservative treatment of the multiligamentous knee injuries. We also provide a review of the literature and guidelines for older adult patients with these types of complex traumatic injuries. Early to mid term acceptable outcomes were achieved for both patients through surgical fixation of the tibial plateau fracture and conservative treatment of the ligament injuries. We propose a comprehensive treatment algorithm for management of these complex injuries.Vani J Sabesan Paul J Danielsky Abby Childs Tom Valikodath 2015World Journal of Orthopedics2015,6,3:14
20Quick image-processing method of UAV without control points data in earthquake disaster area显示文摘The methods of unmanned aerial vehicles images splicing rapidly and rectifying without control points data, only using auxiliary data recorded by unmanned aerial vehicle (UAV) system, were researched. Two algorithms were proposed, including UAV images auto- splicing rapidly after image blocking and UAV images rectifying based on pseudo center points of auxiliary data. When SIFT algorithm for UAV images splicing is applied, the accuracy is very high, but the efficiency is very low. The splicing efficiency is improved greatly based on SIFT algorithm after image blocking. The results show that rectifying accuracy is very high and has no visual dislocation when pseudo center points of auxiliary data is applied.LI Chang-chun1, ZHANG Guang-sheng1, LEI Tian-jie2, 3, GONG A-du2, 3 1. School of Surveying & Land Information Engineering, Henan Polytechnic University, Jiaozuo 454000, China 2. Key Laboratory of Environmental Change and Natural Disaster, Ministry of Education, Beijing Normal University, Beijing 100875, China 3. Ministry of Civil Affairs/Ministry of Education of China Academy of Disaster Reduction and Emergency Management, Beijing Normal University, Beijing 100875, China 2011中国有色金属学会会刊:英文版2011,21,S3:13
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