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Phase-Based Optical Flow Method with Optimized Parameter Settings for Enhancing Displacement Measurement Adaptability
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作者 Zhaoxin Peng Menglian Liu +2 位作者 Zhiliang Wang Wei Liu Xian Wang 《Open Journal of Applied Sciences》 2024年第5期1165-1184,共20页
To enhance the applicability and measurement accuracy of phase-based optical flow method using complex steerable pyramids in structural displacement measurement engineering applications, an improved method of optimizi... To enhance the applicability and measurement accuracy of phase-based optical flow method using complex steerable pyramids in structural displacement measurement engineering applications, an improved method of optimizing parameter settings is proposed. The optimized parameters include the best measurement points of the Region of Interest (ROI) and the levels of pyramid filters. Additionally, to address the issue of updating reference frames in practical applications due to the difficulty in estimating the maximum effective measurement value, a mechanism for dynamically updating reference frames is introduced. Experimental results demonstrate that compared to representative image gradient-based displacement measurement methods, the proposed method exhibits higher measurement accuracy in engineering applications. This provides reliable data support for structural damage identification research based on vibration signals and is expected to broaden the engineering application prospects for structural health monitoring. 展开更多
关键词 Displacement Measurement Phase-Based Optical Flow Optimized Parameter setting
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Multi-objective optimization based optimal setting control for industrial double-stream alumina digestion process
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作者 WANG Xiao-li LU Mei-yu +1 位作者 WEI Si-mi XIE Yong-fang 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第1期173-185,共13页
The operation variables,including feed rate of ore slurry,caustic solution and live steams in the double-stream alumina digestion process,determine the product quality,process costs and the environment pollution.Previ... The operation variables,including feed rate of ore slurry,caustic solution and live steams in the double-stream alumina digestion process,determine the product quality,process costs and the environment pollution.Previously,they were set by the technical workers according to the offline analysis results and an empirical formula,which leads to unstable process indices and high consumption frequently.So,a multi-objective optimization model is built to maintain the balance between resource consumptions and process indices by taking technical indices and energy efficiency as objectives,where the key technical indices are predicted based on the digestion kinetics of diaspore.A multi-objective state transition algorithm(MOSTA)is improved to solve the problem,in which a self-adaptive strategy is applied to dynamically adjust the operator factors of the MOSTA and dynamic infeasible threshold is used to handle constraints to enhance searching efficiency and ability of the algorithm.Then a rule based strategy is designed to make the final decision from the Pareto frontiers.The method is integrated into an optimal control system for the industrial digestion process and tested in the actual production.Results show that the proposed method can achieve the technical target while reducing the energy consumption. 展开更多
关键词 double-stream digestion process optimal setting control multi-objective optimization state transition algorithm rule based decision making
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UNSUPERVISED POLINSAR CLASSIFICATION BASED ON OPTIMAL COHERENCE SET
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作者 Xu Liying Li Shiqiang +1 位作者 Deng Yunkai Robert Wang 《Journal of Electronics(China)》 2013年第4期368-376,共9页
Aiming to solve the misclassification problems of unsupervised polarimetric Wishart clas- sification algorithm based on Freeman decomposition, an unsupervised Polarimetric Synthetic Aper- ture Radar (SAR) Interferot... Aiming to solve the misclassification problems of unsupervised polarimetric Wishart clas- sification algorithm based on Freeman decomposition, an unsupervised Polarimetric Synthetic Aper- ture Radar (SAR) Interferotnery (PolInSAR) classification algorithm based on optimal coherence set parameters is studied and proposed. This algorithm uses the result of Freeman decomposition to divide the image into three basic categories including surface scattering, volume scattering, and double-bounce Then, the PolInSAR optimal coherence set parameters are used to finely divide each of the three basic categories into 9 categories, and the whole image is divided into 27 categories. Because both the Freeman decomposition result and optimal coherence set parameters indicate specific scattering characteristics, the whole image is merged into 16 categories based on physical meaning. At last, the Wishart cluster is employed to obtain the final classification result. To preserve the purity of scattering characteristics, pixels with similar scattering characteristics are restricted to be classified with other pixels. The final classification results effectively resolve the misclassification problem, not only the buildings can be effectively distinguished from vegetation in urban areas, but also the road is well distinguished from grass. In this paper, the E-SAR PolInSAR data of German Aerospace Center (DLR) are used to verify the effectiveness of the algorithm. 展开更多
关键词 Polarimetric SAR Interferomery (PolInSAR) Unsupervised classification Freeman de-composition optimal coherence set parameters
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Application of MPSO technique to find optimal location and parameter setting of TCSC
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作者 王延鹏 蔡兴国 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2011年第3期101-105,共5页
A new mothod was presented to find the optimal location and parameter setting of Thyristor Controlled Series Compensator (TCSC) to maxmize the transfer capability.Firstly the sensitivity of the transfer capability wit... A new mothod was presented to find the optimal location and parameter setting of Thyristor Controlled Series Compensator (TCSC) to maxmize the transfer capability.Firstly the sensitivity of the transfer capability with respect was described to the line's reactance was described to find the more sensitive lines for installing TCSC,however,the line which has the most sesitivity value is always not the best line for installing TCSC.For solving this problem,the more sensitive m lines were selected as the alternative line group of installing TCSC,and then modified particle swarm optimization (MPSO) was used to find out the optimal location and the optimal parameter settings of TCSC.Particle swarm optimization (PSO) algorithm can results premature convergence.For solving this problem,population entropy and cellular automata were introduced to it.Simulation results of IEEE 30-bus system proved the effectiveness of the method and its application values. 展开更多
关键词 TCSC optimal location and parameter settings modified particle swarm optimization continuation oower flow
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Signifying quantum uncertainty relations by optimal observable sets and the tightest uncertainty constants
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作者 Xiao-Bin Liang Bo Li Shao-Ming Fei 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2024年第9期43-50,共8页
Quantum uncertainty relations constrain the precision of measurements across multiple non-commuting quantum mechanical observables.Here,we introduce the concept of optimal observable sets and define the tightest uncer... Quantum uncertainty relations constrain the precision of measurements across multiple non-commuting quantum mechanical observables.Here,we introduce the concept of optimal observable sets and define the tightest uncertainty constants to accurately describe these measurement uncertainties.For any quantum state,we establish optimal sets of three observables for both product and summation forms of uncertainty relations,and analytically derive the corresponding tightest uncertainty constants.We demonstrate that the optimality of these sets remains consistent regardless of the uncertainty relation form.Furthermore,the existence of the tightest constants excludes the validity of standard real quantum mechanics,underscoring the essential role of complex numbers in this field.Additionally,our findings resolve the conjecture posed in[Phys.Rev.Lett.118,180402(2017)],offering novel insights and potential applications in understanding preparation uncertainties. 展开更多
关键词 uncertainty relation the tightest uncertainty constants optimal observable sets
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Calculation Model of Equivalent Strength for Induced Crack Based on Double-K Fracture Theory and Its Optimizing Setting in RCC Arch Dam 被引量:8
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作者 张小刚 宋玉普 吴智敏 《Transactions of Tianjin University》 EI CAS 2005年第1期59-65,共7页
By means of fracture testing on roller-compacted concrete (RCC) three-point bending beams with two different specimen sizes, the P-CMOD complete curve for RCC was gained. Furthermore, by applying double-K fracture t... By means of fracture testing on roller-compacted concrete (RCC) three-point bending beams with two different specimen sizes, the P-CMOD complete curve for RCC was gained. Furthermore, by applying double-K fracture theory, KiniⅠC,KunⅠC, as well as the critical effective crack length and the critical crack tip opening displacement, were evaluated. Based on the double-K fracture parameters above, the calculation model of equivalent strength for induced crack was established, thus the calculation method on its initiation, stable propagation and unstable fracture was ascertained. Moreover, the finite element simulation analysis of stress field in ShaPai arch dam and the on-site observational splaying points of induced crack at different altitudes validated the reliability of the model. Finally, crack inducer′s optimal setting in RCC arch dam was studied. It improves the design level of induced crack in RCC arch dam and satisfies the necessity of engineering practice. 展开更多
关键词 roller-compacted concrete (RCC) arch dam induced crack double-K fracture parameters equivalent strength calculation model optimizing setting
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Coordinated optimization setting of reagent dosages in roughing-scavenging process of antimony flotation 被引量:3
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作者 CAO Bin-fang XIE Yong-fang +2 位作者 GUI Wei-hua YANG Chun-hua LI Jian-qi 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第1期95-106,共12页
Considering the influence of reagent adjustment in different flotation bank on the final production index and the difficulty of establishing an effective mathematical model,a coordinated optimization method for dosage... Considering the influence of reagent adjustment in different flotation bank on the final production index and the difficulty of establishing an effective mathematical model,a coordinated optimization method for dosage reagent based on key characteristics variation tendency and case-based reasoning is proposed.On the basis of the expert reagent regulation method in antimony flotation process,the reagent dosage pre-setting model of the roughing–scavenging bank is constructed based on case-based reasoning.Then,the sensitivity index is used to calculate the key features of reagent dosage.The reagent dosage compensation model is constructed based on the variation tendency of the key features in the roughing and scavenging process.At last,the prediction model is used to finish the classification and discriminant analysis.The simulation results and industrial experiment in antimony flotation process show that the proposed method reduces fluctuation of the tailings indicators and the cost of reagent dosage.It can lay a foundation for optimizing the whole process of flotation. 展开更多
关键词 froth flotation image features optimization setting coordinated optimization
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The Linear Span of a Class of Optimal Frequency Hopping Sequences 被引量:1
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作者 高军涛 胡予濮 李雪莲 《China Communications》 SCIE CSCD 2011年第2期147-151,共5页
For the anti-jamming purpose,frequency hopping sequences are required to have a large linear span. In this paper,we firstly give the linear span of a class of optimal frequency hopping sequences. The results show that... For the anti-jamming purpose,frequency hopping sequences are required to have a large linear span. In this paper,we firstly give the linear span of a class of optimal frequency hopping sequences. The results show that the linear span is very small compared with their periods. To improve the linear span,we transform these optimal frequency hopping sequences into new optimal frequency hopping sequences with large linear span by using a general type of permutation polynomials over a finite field. Furthermore,we give the exact values of the linear span of the transformed optimal frequency hopping sequences. 展开更多
关键词 frequency hopping sequences linear span permutation polynomials optimal sets
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Continuity of Solution Mappings for Parametric Set Optimization Problems under Partial Order Relations
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作者 Yueming Sun 《Advances in Pure Mathematics》 2020年第11期631-644,共14页
This paper mainly investigates the semicontinuity of solution mappings for set optimization problems under a partial order set relation instead of upper and lower set less order relations. To this end, we propose two ... This paper mainly investigates the semicontinuity of solution mappings for set optimization problems under a partial order set relation instead of upper and lower set less order relations. To this end, we propose two types of monotonicity definition for the set-valued mapping introduced by two nonlinear scalarization functions which are presented by these partial order relations. Then, we give some sufficient conditions for the semicontinuity and closedness of solution mappings for parametric set optimization problems. The results presented in this paper are new and extend the main results given by some authors in the literature. 展开更多
关键词 Parametric set Optimization Problem Nonlinear Scalarization Function SEMICONTINUITY Partial Order Relation
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A system for evaluation of ultrasound contrast agent's enhancement effect 被引量:2
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作者 陈平 杨芳 +4 位作者 房坤 顾爱远 钱卓宇 王鹏 顾宁 《Journal of Southeast University(English Edition)》 EI CAS 2010年第1期82-86,共5页
A system for in vitro investigation of ultrasound contrast agent's enhancement effect is presented and evaluated. It includes the digital B-mode ultrasound scanner Belson3000A, the tissue-mimicking ultrasound phantom... A system for in vitro investigation of ultrasound contrast agent's enhancement effect is presented and evaluated. It includes the digital B-mode ultrasound scanner Belson3000A, the tissue-mimicking ultrasound phantoms and the software which is used for image quantitative analysis. The linear range, optimal settings and repeatability of the system are assessed and explored by scanning the ultrasound phantoms with different reflective intensities. The measurements are performed under an acoustic power from 4.8 to 12.3 mW, the scanner centre frequency is 3.5 MH and the gain setting is 50 dB. Both a self-made surfactant encapsulated microbubble and a commercial ultrasound contrast agent are scanned. The results show that the pixel intensity of ultrasonic images increases with the increase in the sound power, and for the stronger reflective phantoms of more particles, the increasing trend is much more evident. The system is optimal for evaluating the microbubble contrast agents' enhancement effects. It presents a simple, effective and real-time means for characterizing the enhancement ability of microbubbles. 展开更多
关键词 MICROBUBBLE ultrasound phantom enhancement imaging optimal settings
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Decision-Making Method for Problem of Goal Type Based on Evaluation Criterion
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作者 蒋尚华 冯勤超 +1 位作者 江孝感 徐南荣 《Journal of Southeast University(English Edition)》 EI CAS 2002年第3期254-258,共5页
The presently existing decision making method for problem of goal type, i.e. the goal programming, is popular to some extent. In this paper we analyzed the features of the problem and the method,based on which we foun... The presently existing decision making method for problem of goal type, i.e. the goal programming, is popular to some extent. In this paper we analyzed the features of the problem and the method,based on which we found some defects of the method and pointed out these defects. To overcome these defects we absorbed the spirit and exploited concepts of evaluation criterion and the fault measure of evaluation criterion. We proposed and applied a method with an evaluation criterion, after which we also p... 展开更多
关键词 multi objective decision making evaluation criterion fault measure of evaluation criterion pre optimized objective set
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Multi Objective Decision Making Method Based on Evaluation Criterion for Problems with Linear Value Function
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作者 蒋尚华 韩勇 徐南荣 《Journal of Southeast University(English Edition)》 EI CAS 1998年第1期114-121,共8页
A class of interactive multi objective decision making method by means of evaluation criterion is proposed for problems with linear value function,in which case,the decision maker(DM) usually has only unwhole infor... A class of interactive multi objective decision making method by means of evaluation criterion is proposed for problems with linear value function,in which case,the decision maker(DM) usually has only unwhole information of weights for objectives. The concept of fault measure of the evaluation criterion is proposed to measure the deviation of the evaluation criterion from the DMs preference structure.The approach to obtain an upper boundary of fault measure of an evaluation criterion,and the approach to modify the evaluation criterion to be one with smaller fault measure,and the approach to obtain a pre optimized objective set by evaluation criterion with certain fault measure are also proposed. 展开更多
关键词 multi objective decision making evaluation criterion fault measure of evaluation criterion pre optimized objective set
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Sensor Configuration and Test for Fault Diagnoses of Subway Braking System Based on Signed Digraph Method 被引量:4
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作者 ZUO Jianyong CHEN Zhongkai 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第3期475-482,共8页
Fault diagnosis of various systems on rolling stock has drawn the attention of many researchers. However, obtaining an optimized sensor set of these systems, which is a prerequisite for fault diagnosis, remains a majo... Fault diagnosis of various systems on rolling stock has drawn the attention of many researchers. However, obtaining an optimized sensor set of these systems, which is a prerequisite for fault diagnosis, remains a major challenge. Available literature suggests that the configuration of sensors in these systems is presently dependent on the knowledge and engineering experiences of designers, which may lead to insufficient or redundant development of various sensors. In this paper, the optimization of sensor sets is addressed by using the signed digraph (SDG) method. The method is modified for use in braking systems by the introduction of an effect-function method to replace the traditional quantitative methods. Two criteria are adopted to evaluate the capability of the sensor sets, namely, observability and resolution. The sensors configuration method of braking system is proposed. It consists of generating bipartite graphs from SDG models and then solving the set cover problem using a greedy algorithm. To demonstrate the improvement, the sensor configuration of the HP2008 braking system is investigated and fault diagnosis on a test bench is performed. The test results show that SDG algorithm can improve single-fault resolution from 6 faults to 10 faults, and with additional four brake cylinder pressure (BCP) sensors it can cover up to 67 double faults which were not considered by traditional fault diagnosis system. SDG methods are suitable for reducing redundant sensors and that the sensor sets thereby obtained are capable of detecting typical faults, such as the failure of a release valve. This study investigates the formal extension of the SDG method to the sensor configuration of braking system, as well as the adaptation supported by the effect-function method. 展开更多
关键词 fault diagnosis subway braking system signed directed graph sensor set optimization.
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Fuzzy pattern recognition method for assessing groundwater vulnerability to pollution in the Zhangji area 被引量:4
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作者 MAO Yuan-yuan ZHANG Xue-gang WANG Lian-sheng 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第11期1917-1922,共6页
Based on the widely used DRASTIC method, a fuzzy pattern recognition and optimization method was proposed and applied to the fissured-karstic aquifer of Zhangji area for assessing groundwater vulnerability to pollutio... Based on the widely used DRASTIC method, a fuzzy pattern recognition and optimization method was proposed and applied to the fissured-karstic aquifer of Zhangji area for assessing groundwater vulnerability to pollution. The result is compared with DRASTIC method. It is shown that by taking the fuzziness into consideration, the fuzzy pattern recognition and optimization method reflects more efficiently the fuzzy nature of the groundwater vulnerability to pollution and is more applicable in reality. 展开更多
关键词 Fuzzy sets recognition and optimization method Groundwater vulnerability to pollution DRASTIC
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Optimization and Mechanical Accuracy Reliability of a New Type of Forging Manipulator 被引量:6
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作者 CHEN Kang MA Chunxiang +1 位作者 ZHENG Maoqi GAO Feng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第2期236-248,共13页
Researches on forging manipulator have enormous influence on the development of the forging industry and national economy.Clamp device and lifting mechanism are the core parts of forging manipulator,and have been stud... Researches on forging manipulator have enormous influence on the development of the forging industry and national economy.Clamp device and lifting mechanism are the core parts of forging manipulator,and have been studied for longer time.However,the optimization and mechanical accuracy reliability of them are less analyzed.Based on General Function(G_F)set and parallel mechanism theory,proper configuration of 10t forging manipulator is selected firstly.A new type of forging manipulator driven by cylinders is proposed.After solved mechanical analysis of manipulator's core mechanisms,expressions of force of cylinders are carried out.In order to achieve smaller force afforded by cylinders and better mechanical characteristics,some particular sizes of core mechanisms are optimized intuitively through the combined use of the genetic algorithms(GA)and GUI interface in MATLAB.Comparing with the original mechanisms,optimized clamp saves at least 8 percent efforts and optimized lifting mechanism 20 percent under maximum working condition.Finally,considering the existed manufacture error of components,mechanical accuracy reliability of optimized clamp,lifting mechanism and whole manipulator are demonstrated respectively based on fuzzy reliability theory.Obtained results show that the accuracy reliability of optimized clamp is bigger than 0.991 and that of optimized lifting mechanism is 0.995.To the whole manipulator under maximum working condition,that value exceeds 0.986 4,which means that optimized manipulator has high motion accuracy and is reliable.A new intuitive method is created to optimize forging manipulator sizes efficiently and more practical theory is utilized to analyze mechanical accuracy reliability of forging manipulator precisely. 展开更多
关键词 forging manipulator G_F set configuration optimization mechanical reliability
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Comparison of Two Types of Control Structures for Benzene Chlorine Reactive Distillation Systems 被引量:2
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作者 薄翠梅 张日东 +3 位作者 张程浩 汤吉海 乔旭 高福荣 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第7期837-841,共5页
The "neat" operation of the two-reactant reactive distillation column has Oetter steady-state economics, while It presents a challenge for design, optimization, and control of the process. Based on the optimal econo... The "neat" operation of the two-reactant reactive distillation column has Oetter steady-state economics, while It presents a challenge for design, optimization, and control of the process. Based on the optimal economic design, the dual-composition control structure and dual-temperature control structure are designed respectively for the benzene chlorine consecutive reactive distillation process. The effectiveness and robustness are analyzed comparably for the disturbance resistance in terms of changes of production rate and feed composition. Results show that dual-temperature control with propose selection of tray temperatures and the optimal profile of the set point can provide better transient process performance than the composition control structure. 展开更多
关键词 Reactive distillation Decentralized control structures optimal set point Benzene chloride production
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Multi-Source Adaptive Selection and Fusion for Pedestrian Dead Reckoning 被引量:1
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作者 Yuanxun Zheng Qinghua Li +2 位作者 Changhong Wang Xiaoguang Wang Lifeng Hu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2022年第12期2174-2185,共12页
Accurate multi-source fusion is based on the reliability, quantity, and fusion mode of the sources. The problem of selecting the optimal set for participating in the fusion process is nondeterministic-polynomial-time-... Accurate multi-source fusion is based on the reliability, quantity, and fusion mode of the sources. The problem of selecting the optimal set for participating in the fusion process is nondeterministic-polynomial-time-hard and is neither sub-modular nor super-modular. Furthermore, in the case of the Kalman filter(KF) fusion algorithm, accurate statistical characteristics of noise are difficult to obtain, and this leads to an unsatisfactory fusion result. To settle the referred cases, a distributed and adaptive weighted fusion algorithm based on KF has been proposed in this paper. In this method, on the basis of the pseudo prior probability of the estimated state of each source, the reliability of the sources is evaluated and the optimal set is selected on a certain threshold. Experiments were performed on multi-source pedestrian dead reckoning for verifying the proposed algorithm. The results obtained from these experiments indicate that the optimal set can be selected accurately with minimal computation, and the fusion error is reduced by 16.6% as compared to the corresponding value resulting from the algorithm without improvements.The proposed adaptive source reliability and fusion weight evaluation is effective against the varied-noise multi-source fusion system, and the fusion error caused by inaccurate statistical characteristics of the noise is reduced by the adaptive weight evaluation.The proposed algorithm exhibits good robustness, adaptability,and value on applications. 展开更多
关键词 Adaptive reliability evaluation adaptive weight evaluation Kalman filter(KF) multi-source fusion optimal set selection
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Fuzzy linear model for production optimization of mining systems with multiple entities 被引量:1
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作者 Slobodan Vujic Tomo Benovic +3 位作者 Igor Miljanovic Marjan Hudej Aleksandar Milutinovic Petar Pavlovic 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2011年第6期633-637,共5页
Planning and production optimization within multiple mines or several work sites (entities) mining systems by using fuzzy linear programming (LP) was studied. LP is the most commonly used operations research metho... Planning and production optimization within multiple mines or several work sites (entities) mining systems by using fuzzy linear programming (LP) was studied. LP is the most commonly used operations research methods in mining engineering. After the introductory review of properties and limitations of applying LP, short reviews of the general settings of deterministic and fuzzy LP models are presented. With the purpose of comparative analysis, the application of both LP models is presented using the example of the Bauxite Basin Niksic with five mines. After the assessment, LP is an efficient mathematical modeling tool in production planning and solving many other single-criteria optimization problems of mining engineering. After the comparison of advantages and deficiencies of both deterministic and fuzzy LP models, the conclusion presents benefits of the fuzzy LP model but is also stating that seeking the optimal plan of production means to accomplish the overall analysis that will encompass the LP model approaches. 展开更多
关键词 linear programming fuzzy set theory optimization production planning bauxite mines
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Synergetic Optimization of Missile Shapes for Aerodynamic and Radar Cross-Section Performance Based on Multi-objective Evolutionary Algorithm
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作者 刘洪 《Journal of Shanghai Jiaotong university(Science)》 EI 2004年第2期36-40,共5页
A multiple-objective evolutionary algorithm (MOEA) with a new Decision Making (DM) scheme for MOD of conceptual missile shapes was presented, which is contrived to determine suitable tradeoffs from Pareto optimal set ... A multiple-objective evolutionary algorithm (MOEA) with a new Decision Making (DM) scheme for MOD of conceptual missile shapes was presented, which is contrived to determine suitable tradeoffs from Pareto optimal set using interactive preference articulation. There are two objective functions, to maximize ratio of lift to drag and to minimize radar cross-section (RCS) value. 3D computational electromagnetic solver was used to evaluate RCS, electromagnetic performance. 3D Navier-Stokes flow solver was adopted to evaluate aerodynamic performance. A flight mechanics solver was used to analyze the stability of the missile. Based on the MOEA, a synergetic optimization of missile shapes for aerodynamic and radar cross-section performance is completed. The results show that the proposed approach can be used in more complex optimization case of flight vehicles. 展开更多
关键词 multi-objective design(MOD) multidisciplinary design optimization (MDO) evolutionary algorithm synergetic optimization decision making scheme interactive preference articulation Pareto optimal set
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Solution set calculation of the Sun-perturbed optimal two-impulse trans-lunar orbits using continuation theory
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作者 Bo-yong He Hong-xin Shen 《Astrodynamics》 CSCD 2020年第1期75-86,共12页
The solution set of the Sun-perturbed optimal two-impulse trans-lunar orbit is helpful for overall optimization of the lunar exploration mission.A model for computing the two-impulse trans-lunar orbit,which strictly s... The solution set of the Sun-perturbed optimal two-impulse trans-lunar orbit is helpful for overall optimization of the lunar exploration mission.A model for computing the two-impulse trans-lunar orbit,which strictly satisfies the boundary constraints,is established.The solution set is computed first with a circular restricted three-body model using a generalized local gradient optimization algorithm and the strategy of design variable initial continuation.By taking the solution set of a circular restricted three-body model as the initial values of the design variables,the Sun-perturbed solution set is calculated based on the dynamic model continuation theory and traversal search methodology.A comparative analysis shows that the fuel cost may be reduced to some extent by considering the Sun’s perturbation and choosing an appropriate transfer window.Moreover,there are several optimal two-impulse trans-lunar methods for supporting a lunar mission to select a scenario with a certain ground measurement and to control the time cost.A fitted linear dependence relationship between the Sun’s befitting phase and the trans-lunar duration could thus provide a reference to select a low-fuel-cost trans-lunar injection window in an engineering project. 展开更多
关键词 trans-lunar orbit optimization optimal solution set continuation theory Sun-perturbed
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