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Hierarchical Bayesian Calibration and On-line Updating Method for Influence Coefficient of Automatic Dynamic Balancing Machine 被引量:7
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作者 ZHANG Jian WU Jianwei MA Zhiyong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第6期876-882,共7页
Measurement error of unbalance's vibration response plays a crucial role in calibration and on-line updating of influence coefficient(IC). Focusing on the two problems that the moment estimator of data used in cali... Measurement error of unbalance's vibration response plays a crucial role in calibration and on-line updating of influence coefficient(IC). Focusing on the two problems that the moment estimator of data used in calibration process cannot fulfill the accuracy requirement under small sample and the disturbance of measurement error cannot be effectively suppressed in updating process, an IC calibration and on-line updating method based on hierarchical Bayesian method for automatic dynamic balancing machine was proposed. During calibration process, for the repeatedly-measured data obtained from experiments with different trial weights, according to the fact that measurement error of each sensor had the same statistical characteristics, the joint posterior distribution model for the true values of the vibration response under all trial weights and measurement error was established. During the updating process, information obtained from calibration was regarded as prior information, which was utilized to update the posterior distribution of IC combined with the real-time reference information to implement online updating. Moreover, Gibbs sampling method of Markov Chain Monte Carlo(MCMC) was adopted to obtain the maximum posterior estimation of parameters to be estimated. On the independent developed dynamic balancing testbed, prediction was carried out for multiple groups of data through the proposed method and the traditional method respectively, the result indicated that estimator of influence coefficient obtained through the proposed method had higher accuracy; the proposed updating method more effectively guaranteed the measurement accuracy during the whole producing process, and meantime more reasonably compromised between the sensitivity of IC change and suppression of randomness of vibration response. 展开更多
关键词 influence coefficient hierarchical Bayesian calibration online updating dynamic balancing Markov Chain Monte Carlo(MCMC)
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Dynamic Load Balancing Based on Restricted Multicast Tree in Homogeneous Multiprocessor Systems 被引量:1
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作者 刘滨 石峰 高玉金 《Journal of Beijing Institute of Technology》 EI CAS 2008年第2期184-188,共5页
To decrease the cost of exchanging load information among processors, a dynamic load-balancing (DLB) algorithm which adopts multieast tree technology is proposed. The muhieast tree construction rules are also propos... To decrease the cost of exchanging load information among processors, a dynamic load-balancing (DLB) algorithm which adopts multieast tree technology is proposed. The muhieast tree construction rules are also proposed to avoid wrongly transferred or redundant DLB messages due to the overlapping of multicast trees. The proposed DLB algorithm is distributed controlled, sender initiated and can help heavily loaded processors with complete distribution of redundant loads with minimum number of executions. Experiments were executed to compare the effects of the proposed DLB algorithm and other three ones, the results prove the effectivity and practicability of the proposed algorithm in dealing with great scale compute-intensive tasks. 展开更多
关键词 dynamic load balancing (DLB) multicast tree RULE MESSAGE MULTIPROCESSOR
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MDSLB:A new static load balancing method for parallel molecular dynamics simulations 被引量:1
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作者 武云龙 徐新海 +2 位作者 杨学军 邹顺 任小广 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第2期628-643,共16页
Large-scale parallelization of molecular dynamics simulations is facing challenges which seriously affect the simula- tion efficiency, among which the load imbalance problem is the most critical. In this paper, we pro... Large-scale parallelization of molecular dynamics simulations is facing challenges which seriously affect the simula- tion efficiency, among which the load imbalance problem is the most critical. In this paper, we propose, a new molecular dynamics static load balancing method (MDSLB). By analyzing the characteristics of the short-range force of molecular dynamics programs running in parallel, we divide the short-range force into three kinds of force models, and then pack- age the computations of each force model into many tiny computational units called "cell loads", which provide the basic data structures for our load balancing method. In MDSLB, the spatial region is separated into sub-regions called "local domains", and the cell loads of each local domain are allocated to every processor in turn. Compared with the dynamic load balancing method, MDSLB can guarantee load balance by executing the algorithm only once at program startup without migrating the loads dynamically. We implement MDSLB in OpenFOAM software and test it on TianHe-lA supercomputer with 16 to 512 processors. Experimental results show that MDSLB can save 34%-64% time for the load imbalanced cases. 展开更多
关键词 molecular dynamics static load balancing parallel computing
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THE DESIGN AND ANALYSIS OF VIBRATION STRUCTURE OF VERTICAL DYNAMIC BALANCING MACHINE 被引量:1
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作者 LiDinggen CaoJiguang +1 位作者 WangJtmwen ChenChuanyao 《Acta Mechanica Solida Sinica》 SCIE EI 2004年第2期172-182,共11页
A new type of vibration structure (i.e. supporting system, called swing frame cus- tomarily) of vertical dynamic balancing machine has been designed, which is based on an analysis for the swing frame of a traditiona... A new type of vibration structure (i.e. supporting system, called swing frame cus- tomarily) of vertical dynamic balancing machine has been designed, which is based on an analysis for the swing frame of a traditional double-plane vertical dynamic balancing machine. The static unbalance and couple unbalance can be e?ectively separated by using the new dynamic balancing machine with the new swing frame. By building the dynamics model, the advantages of the new structure are discussed in detail. The modal and harmonic response are analyzed by using the ANSYS7.0. By comparing the ?nite element modal analysis with the experimental modal analy- sis, the natural frequencies and vibration modes are found. There are many spring boards in the new swing frame. Their sti?nesses are di?erent and assorted with each other. Furthermore, there are three sensors on the measuring points. Therefore, the new dynamic balancing machine can measure static unbalance and coupling unbalance directly, and the interaction between them is faint. The result shows that the new vertical dynamic balancing machine is suitable for inertial measurement of ?ying objects, and can overcome the shortcomings of traditional double-plane vertical dynamic balancing machines, which the e?ect of plane-separation is inferior. The vertical dynamic balancing machine with the new vibration structure can ?nd wide application in the future. The modelling and analysis of the new vibration structure will provide theoretical basis and practical experience for designing new-type vertical dynamic balancing machines. 展开更多
关键词 vertical dynamic balancing machine vibration structure static unbalance coupled unbalance modal analysis harmonic response analysis
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A Dynamic Load Balancing Method of Cloud-Center Based on SDN 被引量:6
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作者 WANG Yong TAO Xiaoling +1 位作者 HE Qian KUANG Yuwen 《China Communications》 SCIE CSCD 2016年第2期130-137,共8页
In order to achieve dynamic load balancing based on data fl ow level, in this paper, we apply SDN technology to the cloud data center, and propose a dynamic load balancing method of cloud center based on SDN. The appr... In order to achieve dynamic load balancing based on data fl ow level, in this paper, we apply SDN technology to the cloud data center, and propose a dynamic load balancing method of cloud center based on SDN. The approach of using the SDN technology in the current task scheduling flexibility, accomplish real-time monitoring of the service node flow and load condition by the Open Flow protocol. When the load of system is imbalanced, the controller can allocate globally network resources. What's more, by using dynamic correction, the load of the system is not obvious tilt in the long run. The results of simulation show that this approach can realize and ensure that the load will not tilt over a long period of time, and improve the system throughput. 展开更多
关键词 动态负载平衡算法 SDN 平衡方法 系统吞吐量 负载不平衡 数据中心 任务调度 节点流量
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NEW TYPE OF VIBRATION STRUCTURE OF VERTICAL DYNAMIC BALANCING MACHINE 被引量:9
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作者 LiDinggen CaoJiguang +1 位作者 ChenChuanyao WangJunwen 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2004年第4期579-584,共6页
A new type of vibration structure of vertical dynamic balancing machine isdesigned, which is based on the analysis for swing frame of a traditional vertical dynamic balancingmachine. The static unbalance and couple un... A new type of vibration structure of vertical dynamic balancing machine isdesigned, which is based on the analysis for swing frame of a traditional vertical dynamic balancingmachine. The static unbalance and couple unbalance can be separated effectively by using the newmachine with the new swing frame. By building the dynamics model, the advantages of the newstructure are discussed in detail. The modal and harmonic response are analyzed by using theANSYS7.0. By comparing the finite element modal analysis with the experimental modal analysis, thenatural frequencies and vibration modes are found out. There are many spring boards in the new swingframe. Their stiffness is different and assort with each other. Furthermore, there are threesensors on the measurement points. Therefore, the new dynamic balancing machine can measure thestatic unbalance and couple unbalance directly, and the influence between them is faint. The newstructure has the function of belt-strain compensation to improve the measurement precision. Thepractical result indicates that the new vertical dynamic balancing machine is suitable for inertialmeasurement of flying objects, and can overcome the shortcomings of traditional double-planevertical dynamic balancing machines. The vertical dynamic balancing machine with the new vibrationstructure can be widely used in the future applications. The modeling and analysis of the newvibration structure provide theoretic instruction and practical experience for designing new type ofvertical dynamic balancing machines. Based on the design principles such as stiffness-matching,frequency-adjacence and strain-compensation and so on, various new type of vibration structures canbe designed. 展开更多
关键词 Vertical-dynamic-balancing-machine Vibration-structure Static-unbalance Couple-unbalance Modal-analysis
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LOW-COST HIGH PERFORMANCE CLUSTER OF WORK-STATIONS BASED ON DYNAMIC LOAD BALANCING FOR PARALLEL DEPTH-FIRST SEARCH(DFS)
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作者 Mohammed A. +2 位作者 M.Ibrahim(加力) LU Xin-da(陆鑫达) 《Journal of Shanghai Jiaotong university(Science)》 EI 2002年第2期223-226,共4页
This paper presented an idea to replace the traditionally expensive parallel machines by heterogeneous cluster of workstations. To emphasise the usability of cluster of workstations platform for parallel and distribut... This paper presented an idea to replace the traditionally expensive parallel machines by heterogeneous cluster of workstations. To emphasise the usability of cluster of workstations platform for parallel and distributed computing, also the paper presented the status report on the effort and experiences for the implementation of a dynamic load balancing for parallel tree computation depth first search(DFS) on the cluster of a workstations project. It compared the speedup performance obtained from our platform with that obtained from the traditional one. The speedup results show that cluster of workstations can be a serious alternative to the expensive parallel machines. 展开更多
关键词 heterogeneous CLUSTERS of WORKSTATION PARALLEL tree computation DFS dynamic load balancing strategy PARALLEL performance
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CLUSTER OF WORKSTATIONS BASED ON DYNAMIC LOAD BALANCING FOR PARALLEL TREE COMPUTATION DEPTH-FIRST-SEARCH
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作者 加力 陆鑫达 张健 《Journal of Shanghai Jiaotong university(Science)》 EI 2002年第1期26-31,共6页
The real problem in cluster of workstations is the changes in workstation power or number of workstations or dynmaic changes in the run time behavior of the application hamper the efficient use of resources. Dynamic l... The real problem in cluster of workstations is the changes in workstation power or number of workstations or dynmaic changes in the run time behavior of the application hamper the efficient use of resources. Dynamic load balancing is a technique for the parallel implementation of problems, which generate unpredictable workloads by migration work units from heavily loaded processor to lightly loaded processors at run time. This paper proposed an efficient load balancing method in which parallel tree computations depth first search (DFS) generates unpredictable, highly imbalance workloads and moves through different phases detectable at run time, where dynamic load balancing strategy is applicable in each phase running under the MPI(message passing interface) and Unix operating system on cluster of workstations parallel platform computing. 展开更多
关键词 cluster of WORKSTATIONS PARALLEL TREE COMPUTATION DFS task migration dynamic load balancing strategy and TERMINATION detection algorithm
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The Application of Ridge Regression in Dynamic Balancing of Flexible Rotors Based on Influence Coefficient Method
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作者 秦鹏 蔡萍 +1 位作者 胡庆翰 李英霞 《Journal of Shanghai Jiaotong university(Science)》 EI 2006年第1期93-98,共6页
Based on the model structure of the influence coefficient method analyzed in depth by matrix theory,it is explained the reason why the unreasonable and instable correction masses with bigger MSE are obtained by LS inf... Based on the model structure of the influence coefficient method analyzed in depth by matrix theory,it is explained the reason why the unreasonable and instable correction masses with bigger MSE are obtained by LS influence coefficient method when there are correlation planes in the dynamic balancing.It also presened the new ridge regression method for solving correction masses according to the Tikhonov regularization theory,and described the reason why the ridge regression can eliminate the disadvantage of the LS method. Applying this new method to dynamic balancing of gas turbine, it is found that this method is superior to the LS method when influence coefficient matrix is ill-conditioned,the minimal correction masses and residual vibration are obtained in the dynamic balancing of rotors. 展开更多
关键词 dynamic balancing ridge regression influence coefficient least squares method
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Optimization of Load Balancing Algorithm for Virtual Machine Dynamic Migration under Mobile Cloud Computing
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作者 Weijin Jiang Fang Ye +3 位作者 Shengjie Yang Wei Liu Xiaoliang Liu Sijian Lv 《China Communications》 SCIE CSCD 2020年第6期237-245,共9页
As one of the key technologies of cloud computing,the virtualization technology can virtualize all kinds of resources and integrate them into the unified planning of the cloud computing management platform.The migrati... As one of the key technologies of cloud computing,the virtualization technology can virtualize all kinds of resources and integrate them into the unified planning of the cloud computing management platform.The migration of virtual machines is one of the important technologies of virtual machine applications.However,there are still many deficiencies in the implementation of load balancing by virtual machine dynamic migration in cloud computing.Traditional triggering strategy thresholds are mostly fixed.If there is an instantaneous peak,it will cause migration,which will cause a waste of resources.In order to solve this problem,based on improving the dynamic migration framework,this paper proposes node selection optimization algorithm and node load balancing strategy and designs a prediction module,which uses a one-time smooth prediction to avoid the shortcoming of peak load moment.The simulation experiments and conclusions analysis results show that the fusion algorithm has performance advantages obvious. 展开更多
关键词 cloud computing dynamic migration load balance node selection load value prediction
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Dynamic load balancing with learning model for Sudoku solving system
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作者 Nattapong Kitsuwan Praphan Pavarangkoon +1 位作者 Hendro Mulyo Widiyanto Eiji Oki 《Digital Communications and Networks》 SCIE 2020年第1期108-114,共7页
This paper proposes a dynamic load balancing with learning model for a Sudoku problem solving system that has multiple workers and multiple solvers.The objective is to minimise the total processing time of problem sol... This paper proposes a dynamic load balancing with learning model for a Sudoku problem solving system that has multiple workers and multiple solvers.The objective is to minimise the total processing time of problem solving.Our load balancing with learning model distributes each Sudoku problem to an appropriate pair of worker and solver when it is received by the system.The information of the estimated solution time for a specific number of given input values,the estimated finishing time of each worker,and the idle status of each worker is used to determine the worker-solver pairs.In addition,the proposed system can estimate the waiting period for each problem.Test results show that the system has shorter processing time than conventional alternatives. 展开更多
关键词 dynamic load balancing Learning model SUDOKU
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Dynamic Balancing Structure Optimal Design for the Rotating Arc Sensor
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作者 刘继忠 翟强 +2 位作者 祝顺风 叶艳辉 李志刚 《Journal of Donghua University(English Edition)》 EI CAS 2017年第3期367-370,共4页
Rotating arc sensor is a key device for automation welding. The vibration has a big influence on signal's correct collection and reliable automatic welding. In order to solve the vibration problem and the dynamic ... Rotating arc sensor is a key device for automation welding. The vibration has a big influence on signal's correct collection and reliable automatic welding. In order to solve the vibration problem and the dynamic balancing design with the restricted space,a bearing force analysis based dynamic balancing structure optimal design is proposed and implemented with the help of Pro/Engineer( PROE) and automatic dynamic analysis of mechanical systems( ADAMS) virtual prototype technology, in which three parameters of the counterbalance are considered. The method is suitable for the practical online adjustment. The simulation result shows that optimal design based counterbalance structure and parameters can satisfy the space requirement with lower vibration. The methodology provides a new idea for dynamic balancing design and adjustment of rotating arc sensor with adjustable rotation radius. 展开更多
关键词 rotating arc sensor optimal design dynamic balancing structure
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Dynamic Load Balancing with Overlay-Based Reconfiguration for Wireless Sensor Networks
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作者 Hang QIN Li ZHU Zhongbo WU 《Wireless Sensor Network》 2009年第5期482-488,共7页
Wireless sensor networks are characterized by multihop wireless links and resource constrained nodes. In terms of data collection and forwarding scheduling, this paper investigates the load balancing in sensor nodes a... Wireless sensor networks are characterized by multihop wireless links and resource constrained nodes. In terms of data collection and forwarding scheduling, this paper investigates the load balancing in sensor nodes and wireless link based on the performance of wireless sensor networks. Leveraging the property of dissimilarity distribution, a method to quantitatively evaluate the benefits of load balancing is presented, in order to access the profitability. Then a novel Dynamic Load Balancing of Overlay-based WSN (DLBO) algorithm has been put forward. In particular, the tradeoff between transferring ratio and the load imbalance among nodes is discussed. The load balancing method in this paper outperforms others based on balancing factor, different nodes number and data scales of applications. The proposed model and analytical results can be effectively applied for reliability analysis for other wireless applications (e.g., persistent data delivery is involved). 展开更多
关键词 Wireless Sensor Networks WORKLOAD dynamic LOAD balancing DISSIMILARITY MEASURE RECONFIGURATION
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Research on Full Vector Dynamic Balancing Algorithm for Rotors
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作者 YANG Zhi-han WANG Wen-chao 《International Journal of Plant Engineering and Management》 2018年第1期18-23,共6页
Influence coefficient method and the modal balancing method are often used in the dynamic balancing in the past days. These methods sometimes exist a lot of big measurement errors. So, in order to make these errors mu... Influence coefficient method and the modal balancing method are often used in the dynamic balancing in the past days. These methods sometimes exist a lot of big measurement errors. So, in order to make these errors much smaller, and to use the vibration information of the rotor more sufficiently, at last, we put forward the full vector dynamic balancing algorithm. Though the theoretical analysis, and the experiment tests, we can compare with the new method and the old method , study the relationship between the dynamic balancing and the rotation equipment, and the direction of the development. The full vector dynamic balancing algorithm theory can be inferred from the Jeffcott rotor. To compare with the methods which are mentioned before, we can find that the full vector dynamic balancing algorithm is much better than the influence coefficient method and the modal balancing method. We can use the MATLAB program to prove that the full vector dynamic balancing algorithm is much better. So the conclusion is completely right. 展开更多
关键词 full vector dynamic balancing algorithm unbalanced response balancing effect MATLAB
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Dynamic balancing of dual-rotor system with very little rotating speed difference
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作者 杨健 贺世正 王乐勤 《Journal of Zhejiang University Science》 EI CSCD 2003年第1期64-68,共5页
Unbalanced vibration in dual-rotor rotating machinery was studied with numerical simulations and experiments. A new method is proposed to separate vibration signals of inner and outer rotors for a system with very lit... Unbalanced vibration in dual-rotor rotating machinery was studied with numerical simulations and experiments. A new method is proposed to separate vibration signals of inner and outer rotors for a system with very little difference in rotating speeds. Magnitudes and phase values of unbalance defects can be obtained directly by sampling the vibration signal synchronized with reference signal. The balancing process is completed by the reciprocity influence coefficients of inner and outer rotors method. Results showed the advantage of such method for a dual-rotor system as compared with conventional balancing. 展开更多
关键词 区域动态平衡 双转子系统 转速差 旋转电机
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Implementation Study of Dynamic Load Balancing Algorithm of Parallel Tree Computation on Clusters of Heterogeneous Workstation
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作者 Mohammed A.M. Ibrahim M.SaifMokbel 《Journal of Donghua University(English Edition)》 EI CAS 2005年第2期81-86,共6页
The rapid growth of interconnected high performance workstations has produced a new computing paradigm called clustered of workstations computing. In these systems load balance problem is a serious impediment to achie... The rapid growth of interconnected high performance workstations has produced a new computing paradigm called clustered of workstations computing. In these systems load balance problem is a serious impediment to achieve good performance. The main concern of this paper is the implementation of dynamic load balancing algorithm, asynchronous Round Robin (ARR), for balancing workload of parallel tree computation depth-first-search algorithm on Cluster of Heterogeneous Workstations (COW) Many algorithms in artificial intelligence and other areas of computer science are based on depth first search in implicitty defined trees. For these algorithms a load-balancing scheme is required, which is able to evenly distribute parts of an irregularly shaped tree over the workstations with minimal interprocessor communication and without prior knowledge of the tree’s shape. For the (ARR) algorithm only minimal interprocessor communication is needed when necessary and it runs under the MPI (Message passing interface) that allows parallel execution on heterogeneous SUN cluster of workstation platform. The program code is written in C language and executed under UNIX operating system (Solaris version). 展开更多
关键词 工作站 并行树状计算 动态负载平衡 性能度量
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Learning-Based Dynamic Connectivity Maintenance for UAV-Assisted D2D Multicast Communication 被引量:1
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作者 Jingjing Wang Yanjing Sun +3 位作者 Bowen Wang Shenshen Qian Zhijian Tian Xiaolin Wang 《China Communications》 SCIE CSCD 2023年第10期305-322,共18页
Unmanned aerial vehicles(UAVs) enable flexible networking functions in emergency scenarios.However,due to the movement characteristic of ground users(GUs),it is challenging to capture the interactions among GUs.Thus,w... Unmanned aerial vehicles(UAVs) enable flexible networking functions in emergency scenarios.However,due to the movement characteristic of ground users(GUs),it is challenging to capture the interactions among GUs.Thus,we propose a learningbased dynamic connectivity maintenance architecture to reduce the delay for the UAV-assisted device-todevice(D2D) multicast communication.In this paper,each UAV transmits information to a selected GU,and then other GUs receive the information in a multi-hop manner.To minimize the total delay while ensuring that all GUs receive the information,we decouple it into three subproblems according to the time division on the topology:For the cluster-head selection,we adopt the Whale Optimization Algorithm(WOA) to imitate the hunting behavior of whales by abstracting the UAVs and cluster-heads into whales and preys,respectively;For the D2D multi-hop link establishment,we make the best of social relationships between GUs,and propose a node mapping algorithm based on the balanced spanning tree(BST) with reconfiguration to minimize the number of hops;For the dynamic connectivity maintenance,Restricted Q-learning(RQL) is utilized to learn the optimal multicast timeslot.Finally,the simulation results show that our proposed algorithms perfor better than other benchmark algorithms in the dynamic scenario. 展开更多
关键词 cluster-head selection whale optimization algorithm(WOA) balanced spanning tree(BST) multi-hop link establishment dynamic connectivity maintenance
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DYNAMICAL BALANCE STUDY OF RING REDUCER 被引量:2
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作者 Zhu Caichao Qin DatongState Key Laboratory ofMechanical Transmission,Chongqing University,Chongqing 400044, China 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2003年第1期87-90,共4页
The basic structure of epicyclical gear transmission with inner teeth ofsingle-ring, double-ring, three-ring and four-ring reducer are analyzed. The force analysis model ofring reducer is built. Following this, it is ... The basic structure of epicyclical gear transmission with inner teeth ofsingle-ring, double-ring, three-ring and four-ring reducer are analyzed. The force analysis model ofring reducer is built. Following this, it is concluded that the present ring reducer~ have theproblem that the inertia force or the inertia moment is lopsided. On the base of analysis andcalculation the balanced ring reducer which can realize the balance of inertia force and inertiamoment is brought forward, and so is its concrete realizing step. The specimen of the balanced ringreducer is designed and manufactured; the experiment is carried out on the gear transmission testbench. Compared with other ring reducer of the same power, the balanced ring reducer has manyadvantages, such as low vibration noise, low cost and less production difficulty and less heat. Itis the substitute of other ring reducer of the same kind. Therefore, it has important theoreticsignificance and highly practical engineering value. 展开更多
关键词 dynamical balance REDUCER VIBRATION Noise
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Soil phosphorus dynamic, balance and critical P values in longterm fertilization experiment in Taihu Lake region, China 被引量:17
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作者 SHI Lin-lin SHEN Ming-xing +4 位作者 LU Chang-yin WANG Hai-hou ZHOU Xin-wei JIN Mei-juan WU Tong-dong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第12期2446-2455,共10页
Phosphorus(P) is an important macronutrient for plant but can also cause potential environmental risk. In this paper, we studied the long-term fertilizer experiment(started 1980) to assess the soil P dynamic, bala... Phosphorus(P) is an important macronutrient for plant but can also cause potential environmental risk. In this paper, we studied the long-term fertilizer experiment(started 1980) to assess the soil P dynamic, balance, critical P value and the crop yield response in Taihu Lake region, China. To avoid the effect of nitrogen(N) and potassium(K), only the following treatments were chosen for subsequent discussion, including: C0(control treatment without any fertilizer or organic manure), CNK treatment(mineral N and K only), CNPK(balanced fertilization with mineral N, P and K), MNK(integrated organic manure and mineral N and K), and MNPK(organic manure plus balanced fertilization). The results revealed that the response of wheat yield was more sensitive than rice, and no significant differences of crop yield had been detected among MNK, CNPK and MNPK until 2013. Dynamic and balance of soil total P(TP) and Olsen-P showed soil TP pool was enlarged significantly over consistent fertilization. However, the diminishing marginal utility of soil Olsen-P was also found, indicating that high-level P application in the present condition could not increase soil Olsen-P contents anymore. Linear-linear and Mitscherlich models were used to estimate the critical value of Olsen-P for crops. The average critical P value for rice and wheat was 3.40 and 4.08 mg kg^(–1), respectively. The smaller critical P value than in uplands indicated a stronger ability of P supply for crops in this paddy soil. We concluded that no more mineral P should be applied in rice-wheat system in Taihu Lake region if soil Olsen-P is higher than the critical P value. The agricultural technique and management referring to activate the plant-available P pool are also considerable, such as integrated use of low-P organic manure with mineral N and K. 展开更多
关键词 long-term fertilization soil P dynamic soil P balance crop yield critical P value
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An Advanced Dynamic Scheduling for Achieving Optimal Resource Allocation
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作者 R.Prabhu S.Rajesh 《Computer Systems Science & Engineering》 SCIE EI 2023年第1期281-295,共15页
Cloud computing distributes task-parallel among the various resources.Applications with self-service supported and on-demand service have rapid growth.For these applications,cloud computing allocates the resources dyn... Cloud computing distributes task-parallel among the various resources.Applications with self-service supported and on-demand service have rapid growth.For these applications,cloud computing allocates the resources dynami-cally via the internet according to user requirements.Proper resource allocation is vital for fulfilling user requirements.In contrast,improper resource allocations result to load imbalance,which leads to severe service issues.The cloud resources implement internet-connected devices using the protocols for storing,communi-cating,and computations.The extensive needs and lack of optimal resource allo-cating scheme make cloud computing more complex.This paper proposes an NMDS(Network Manager based Dynamic Scheduling)for achieving a prominent resource allocation scheme for the users.The proposed system mainly focuses on dimensionality problems,where the conventional methods fail to address them.The proposed system introduced three–threshold mode of task based on its size STT,MTT,LTT(small,medium,large task thresholding).Along with it,task mer-ging enables minimum energy consumption and response time.The proposed NMDS is compared with the existing Energy-efficient Dynamic Scheduling scheme(EDS)and Decentralized Virtual Machine Migration(DVM).With a Network Manager-based Dynamic Scheduling,the proposed model achieves excellence in resource allocation compared to the other existing models.The obtained results shows the proposed system effectively allocate the resources and achieves about 94%of energy efficient than the other models.The evaluation metrics taken for comparison are energy consumption,mean response time,percentage of resource utilization,and migration. 展开更多
关键词 Cloud computing resource allocation load balance dynamic scheduling dimensionality reduction
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