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Matching while Learning: Wireless Scheduling for Age of Information Optimization at the Edge 被引量:2
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作者 Kun Guo Hao Yang +2 位作者 Peng Yang Wei Feng Tony Q.S.Quek 《China Communications》 SCIE CSCD 2023年第3期347-360,共14页
In this paper,we investigate the minimization of age of information(AoI),a metric that measures the information freshness,at the network edge with unreliable wireless communications.Particularly,we consider a set of u... In this paper,we investigate the minimization of age of information(AoI),a metric that measures the information freshness,at the network edge with unreliable wireless communications.Particularly,we consider a set of users transmitting status updates,which are collected by the user randomly over time,to an edge server through unreliable orthogonal channels.It begs a natural question:with random status update arrivals and obscure channel conditions,can we devise an intelligent scheduling policy that matches the users and channels to stabilize the queues of all users while minimizing the average AoI?To give an adequate answer,we define a bipartite graph and formulate a dynamic edge activation problem with stability constraints.Then,we propose an online matching while learning algorithm(MatL)and discuss its implementation for wireless scheduling.Finally,simulation results demonstrate that the MatL is reliable to learn the channel states and manage the users’buffers for fresher information at the edge. 展开更多
关键词 information freshness Lyapunov opti-mization multi-armed bandit wireless scheduling
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Optimization of flotation variables for the recovery of hematite particles from BHQ ore 被引量:8
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作者 Swagat S. Rath Hrushikesh Sahoo B. Das 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2013年第7期605-611,共7页
The technology for beneficiation of banded iron ores containing low iron value is a challenging task due to increasing demand of quality iron ore in India. A flotation process has been developed to treat one such ore,... The technology for beneficiation of banded iron ores containing low iron value is a challenging task due to increasing demand of quality iron ore in India. A flotation process has been developed to treat one such ore, namely banded hematite quartzite (BHQ) containing 41.8wt% Fe and 41.5wt% SiO2,by using oleic acid, methyl isobutyl carbinol (MIBC), and sodium silicate as the collector, frother, and dispersant, respectively. The relative effects of these variables have been evaluated in half-normal plots and Pareto charts using central composite rotatable design. A quadratic response model has been developed for both Fe grade and recovery and optimized within the experimental range. The optimum reagent dosages are found to be as follows: collector concentration of 243.58 g/t, dispersant concentration of 195.67 g/t, pH 8.69, and conditioning time of 4.8 min to achieve the maximum Fe grade of 64.25% with 67.33% recovery. The predictions of the model with regard to iron grade and recovery are in good agreement with the experimental results. 展开更多
关键词 HEMATITE iron ore treatment FLOTATION metal recovery design of experiments mathematical models opti-mization
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Multi-objective Optimization Design of Wing Structure with the Model Management Framework 被引量:3
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作者 安伟刚 李为吉 苟仲秋 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2006年第1期31-35,共5页
Evolutionary algorithm is time-consuming because of the large number of evolutions and much times of finite element analysis, when it is used to optimize the wing structure of a certain high altitude long endurance un... Evolutionary algorithm is time-consuming because of the large number of evolutions and much times of finite element analysis, when it is used to optimize the wing structure of a certain high altitude long endurance unmanned aviation vehicle(UAV). In order to improve efficiency it is proposed to construct a model management framework to perform the multi-objective optimization design of wing structure. The sufficient accurate approximation models of objective and constraint functions in the wing structure optimization model are built when using the model management framework, therefore in the evolutionary algorithm a number of finite element analyses can he avoided and the satisfactory multi-objective optimization results of the wing structure of the high altitude long endurance UAV are obtained. 展开更多
关键词 wing structure UAV multi-objective opti-mization model management framework SM- MOPSO
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P_1-nonconforming triangular finite element method for elliptic and parabolic interface problems 被引量:2
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作者 Hongbo GUAN Dongyang SHI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2015年第9期1197-1212,共16页
The lowest order Pl-nonconforming triangular finite element method (FEM) for elliptic and parabolic interface problems is investigated. Under some reasonable regularity assumptions on the exact solutions, the optima... The lowest order Pl-nonconforming triangular finite element method (FEM) for elliptic and parabolic interface problems is investigated. Under some reasonable regularity assumptions on the exact solutions, the optimal order error estimates are obtained in the broken energy norm. Finally, some numerical results are provided to verify the theoretical analysis. 展开更多
关键词 P1-nonconforming finite element method (FEM) interface problem opti-mal order error estimate
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Robot stereo vision calibration method with genetic algorithm and particle swarm optimization 被引量:1
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作者 汪首坤 李德龙 +1 位作者 郭俊杰 王军政 《Journal of Beijing Institute of Technology》 EI CAS 2013年第2期213-221,共9页
Accurate stereo vision calibration is a preliminary step towards high-precision visual posi- tioning of robot. Combining with the characteristics of genetic algorithm (GA) and particle swarm optimization (PSO), a ... Accurate stereo vision calibration is a preliminary step towards high-precision visual posi- tioning of robot. Combining with the characteristics of genetic algorithm (GA) and particle swarm optimization (PSO), a three-stage calibration method based on hybrid intelligent optimization is pro- posed for nonlinear camera models in this paper. The motivation is to improve the accuracy of the calibration process. In this approach, the stereo vision calibration is considered as an optimization problem that can be solved by the GA and PSO. The initial linear values can be obtained in the frost stage. Then in the second stage, two cameras' parameters are optimized separately. Finally, the in- tegrated optimized calibration of two models is obtained in the third stage. Direct linear transforma- tion (DLT), GA and PSO are individually used in three stages. It is shown that the results of every stage can correctly find near-optimal solution and it can be used to initialize the next stage. Simula- tion analysis and actual experimental results indicate that this calibration method works more accu- rate and robust in noisy environment compared with traditional calibration methods. The proposed method can fulfill the requirements of robot sophisticated visual operation. 展开更多
关键词 robot stereo vision camera calibration genetic algorithm (GA) particle swarm opti-mization (PSO) hybrid intelligent optimization
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Enhanced light absorption of silicon in the near-infrared band by designed gold nanostructures
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作者 刘菊 钟晓岚 李志远 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第4期551-556,共6页
A scheme to enhance near-infrared band absorption of a Si nanoparticle by placing the Si nanoparticle into a designed gold nanostructure is proposed. Three-dimensional (3D) finite-difference time-domain simulations ... A scheme to enhance near-infrared band absorption of a Si nanoparticle by placing the Si nanoparticle into a designed gold nanostructure is proposed. Three-dimensional (3D) finite-difference time-domain simulations are employed to calcu- late the absorption spectrum of the Si nanostructure and maximize it by generating alternate designs. The results show that in the near-infrared region over 700 nm, the absorption of a pure Si nanoparticle is very low, but when the same nanoparticle is placed within an optimally designed gold nanostructure, its absorption cross section can be enhanced by more than two orders of magnitude in the near-infrared band. 展开更多
关键词 surface plasmon resonance NEAR-INFRARED silicon absorption finite-difference time-domain opti-mization
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Optimal Policies for Managing Invasive Species under Uncertainty
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作者 C. S. Kim Marcel Aillery +1 位作者 Jan Lewandrowski SeungGyu Kim 《Applied Mathematics》 2012年第10期1388-1394,共7页
We present an optimal control model of three stages of resources allocation for managing invasive species. Three types of temporal uncertainty are considered, involving the timing of discovery of an invasive pest, the... We present an optimal control model of three stages of resources allocation for managing invasive species. Three types of temporal uncertainty are considered, involving the timing of discovery of an invasive pest, the timing of an induced technology development after the establishment and dispersion of an invasive species, and the timing of farmer adoption of induced technology as the costs of controlling the invasive species increase. Using a bioeconomic optimal control model of managing invasive species, where models in previous studies are subset within our model, we show that when sub-structured models not including all three stages are used for managing invasive species, resource allocation for adopting preventive measures before the initial discovery of an invasive pest would be supra-optimalwhile resource allocation for adopting conventional control measures after establishment and dispersion would be sub-optimal. 展开更多
关键词 INVASIVE Species PREVENTIVE Measures CONTROL Measures Induced Technology HAZARD Function opti-mal CONTROL Model
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Design of Poiseuille Flow Controllers Using the Method of Inequalities
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作者 John McKernan James F. Whidborne George Papadakis 《International Journal of Automation and computing》 EI 2009年第1期14-21,共8页
This paper investigates the use of the method of inequalities (MoI) to design output-feedback compensators for the problem of the control of instabilities in a laminar plane Poiseuille flow. In common with many flow... This paper investigates the use of the method of inequalities (MoI) to design output-feedback compensators for the problem of the control of instabilities in a laminar plane Poiseuille flow. In common with many flows, the dynamics of streamwise vortices in plane Poiseuille flow are very non-normal. Consequently, small perturbations grow rapidly with a large transient that may trigger nonlinearities and lead to turbulence even though such perturbations would, in a linear flow model, eventually decay. Such a system can be described as a conditionally linear system. The sensitivity is measured using the maximum transient energy growth, which is widely used in the fluid dynamics community. The paper considers two approaches. In the first approach, the MoI is used to design low-order proportional and proportional-integral (PI) controllers. In the second one, the MoI is combined with McFarlane and Glover's H∞ loop-shaping design procedure in a mixed-optimization approach. 展开更多
关键词 Transient energy growth transient behaviour flow control Poiseuille flow method of inequalities (MoI) mixed opti-mization H∞-optimization.
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Differential Evolution Immunized Ant Colony Optimization Technique in Solving Economic Load Dispatch Problem
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作者 N. A. Rahmat I. Musirin 《Engineering(科研)》 2013年第1期157-162,共6页
Since the introduction of Ant Colony Optimization (ACO) technique in 1992, the algorithm starts to gain popularity due to its attractive features. However, several shortcomings such as slow convergence and stagnation ... Since the introduction of Ant Colony Optimization (ACO) technique in 1992, the algorithm starts to gain popularity due to its attractive features. However, several shortcomings such as slow convergence and stagnation motivate many researchers to stop further implementation of ACO. Therefore, in order to overcome these drawbacks, ACO is proposed to be combined with Differential Evolution (DE) and cloning process. This paper presents Differential Evolution Immunized Ant Colony Optimization (DEIANT) technique in solving economic load dispatch problem. The combination creates a new algorithm that will be termed as Differential Evolution Immunized Ant Colony Optimization (DEIANT). DEIANT was utilized to optimize economic load dispatch problem. A comparison was made between DEIANT and classical ACO to evaluate the performance of the new algorithm. In realizing the effectiveness of the proposed technique, IEEE 57-Bus Reliable Test System (RTS) has been used as the test specimen. Results obtained from the study revealed that the proposed DEIANT has superior computation time. 展开更多
关键词 ANT COLONY Optimization (ACO) DIFFERENTIAL EVOLUTION (DE) DIFFERENTIAL EVOLUTION Immunized ANT COLONY opti-mization (DEIANT)
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Analysis of Finger Muscular Forces using a Wearable Hand Exoskeleton System 被引量:7
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作者 Suin Kim Jeongsoo Lee Joonbum Bae 《Journal of Bionic Engineering》 SCIE EI CSCD 2017年第4期680-691,共12页
In this paper, the finger muscular forces were estimated and analyzed through the application of inverse dynamics-based static optimization, and a hand exoskeleton system was designed to pull the fingers and measure t... In this paper, the finger muscular forces were estimated and analyzed through the application of inverse dynamics-based static optimization, and a hand exoskeleton system was designed to pull the fingers and measure the dynamics of the hand. To solve the static optimization, a muscular model of the hand flexors was derived. The experimental protocol was devised to analyze finger flexors in order to evaluate spasticity of the clenched fingers; muscular forces were estimated while the flexed fingers were extended by the exoskeleton with external loads applied. To measure the finger joint angles, the hand exoskeleton system was designed using four-bar linkage structure and potentiometers. In addition, the external loads to the fingertips were generated by cable driven actuators and simultaneously measured by loadcells which were located at each phalanx. The ex- periments were performed with a normal person and the muscular forces estimation results were discussed with reference to the physical phenomena. 展开更多
关键词 hand rehabilitation wearable system bionic exoskeleton musculoskeletal model inverse dynamics static opti-mization
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Parallel Algorithms for Large-scale Linearly Constrained Minimization Problem
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作者 Cong-ying HAN Fang-ying ZHENG +1 位作者 Tian-de GUO Guo-ping HE 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2014年第3期707-720,共14页
In this paper, two PVD-type algorithms are proposed for solving inseparable linear constraint optimization. Instead of computing the residual gradient function, the new algorithm uses the reduced gradients to construc... In this paper, two PVD-type algorithms are proposed for solving inseparable linear constraint optimization. Instead of computing the residual gradient function, the new algorithm uses the reduced gradients to construct the PVD directions in parallel computation, which can greatly reduce the computation amount each iteration and is closer to practical applications for solve large-scale nonlinear programming. Moreover, based on an active set computed by the coordinate rotation at each iteration, a feasible descent direction can be easily obtained by the extended reduced gradient method. The direction is then used as the PVD direction and a new PVD algorithm is proposed for the general linearly constrained optimization. And the global convergence is also proved. 展开更多
关键词 nonlinear programming large-scale minimization parallel algorithm constrained convex opti-mization
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Nonlinear Distributed Model Predictive Control for Multiple Missiles Against Maneuvering Target with a Trajectory Predictor
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作者 ZHANG Xue CUI Hao +1 位作者 LUO Qianyue ZHANG Hui 《Journal of Shanghai Jiaotong university(Science)》 EI 2020年第6期779-789,共11页
This study aims to solve the problem of multi-missile simultaneous attacks on maneuvering target.The challenges include multimissile cooperative control and target's trajectory prediction.A controller based on non... This study aims to solve the problem of multi-missile simultaneous attacks on maneuvering target.The challenges include multimissile cooperative control and target's trajectory prediction.A controller based on nonlinear distributed model predictive control(NDMPC)is designed for multiple missiles against a maneuvering target,and a trajectory prediction inethod based on particle swarm optimization(PSO)algorithm is proposed.This study has mainly completed the following three aspects of work.Firstly,the cost function of the cont roller is constructed to optimize the accuracy and synchronization of the multi-missile system with consideration of collision avoidance.Secondly,the velocity control of the leading missile is designed by using the range-to-go in-formation in real time to ensure the attack fficiency and the control of the terminal velocity difference.Finally,a kinematic model of the target is cstimated by using short-term real-time data with the PSO algorithm.The established model is employed to predict the target trajectory in the interval between radar scans.Numerical simulation results of two different s enarios demonstrate the effectiveness of the proposed cooperative guidance approach. 展开更多
关键词 multiple missiles no1 linear distributed model predictive control(NDMPC) particle swarm opti-mization(PSO) trajectory predictiom cooperative guidance
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