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A distributed Reconfiguration Approach for Quality-of-Service Provisioning in Dynamic Heterogeneous Wireless Sensor Networks

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ACM TRANSACTIONS ON SENSOR NETWORKS 2015年第2期11卷 1–41页

作者： Steine, Marcel Geilen, Marc Basten, Twan Eindhoven Univ Technol NL-5600 MB Eindhoven Netherlands TNO ESI Eindhoven Netherlands

Wireless Sensor Networks (WSNs) are commonly deployed in dynamic environments where events, such as moving sensor nodes and changing external interference, impact the performance, or Quality of Service (QoS), of the network. QoS is expressed by the values of multiple, possibly conflicting, network quality metrics, such as network lifetime and maximum latency of communicating a packet to the sink. Sufficient QoS should be provided by the WSN to ensure that the end-user can successfully use the WSN to perform its application. We propose a distributed reconfiguration approach that actively maintains a sufficient level of QoS at runtime for a heterogeneous WSN in a dynamic environment. Every node uses a feedback control strategy to resolve any difference between the current and required QoS of the network by adapting controllable parameters of the protocol stack. Example parameters are the transmission power and maximum number of packet retransmissions. Nodes collaborate such that, with the combined adaptations, the required network QoS is achieved. The behavior of the reconfiguration approach and the tradeoffs involved are analyzed in detail. With the use of simulations and experiments with actual deployments, we show that our approach allows a better optimization of QoS objectives while constraints are met;for example, it achieves the same packet loss with a significantly longer lifetime, compared to current (re-)configuration approaches.

关键词： Design algorithms Performance Wireless sensor networks runtime reconfiguration feedback control tradeoffs dynamism heterogeneity distributed algorithm Quality-of-Service

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distributed spatial reuse distance control for basic safety messages inSDMA-based VANETs

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VEHICULAR COMMUNICATIONS 2015年第1期2卷 27-35页

作者： Javed, Muhammad Awais Duy Trong Ngo Khan, Jamil Yusuf Univ Newcastle Sch Elect Engn & Comp Sci Callaghan NSW 2308 Australia

The periodic generation and transmission of basic safety messages (BSM) place a heavy burden on the load of a vehicular ad hoc network (VANET), where there also remain multiple packet collisions undetected due to the hidden terminals. In this paper, we propose a distributed scheme that controls the spatial reuse distance to improve the efficiency of BSM transmissions in space-division multiple access (SDMA) based VANETs. With the proposed SDMA structure, only vehicles located sufficiently far apart are allowed to reuse the same time slot to send their BSMs. The signal interference is thus reduced while the hidden-node problem is essentially alleviated. Multiple transmissions per SDMA road segment or 'cell' are also enabled using the Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA), giving rise to a much better use of both space and bandwidth. To guarantee that the actual number of BSM transmissions does not exceed the maximum allowable in each SDMA cell, we further devise an adaptive scheme that adjusts the spatial reuse distance in accordance with the vehicle density. Because the global information of vehicle density is not available at individual vehicles, we propose a distributed algorithm that estimates the vehicle density and makes consensus to enhance the accuracy of spatial reuse distance estimation. As the transmission range is controlled accordingly, the mutual interference among the SDMA cells is further reduced. Importantly, the developed control algorithm can be distributively implemented by each vehicle with limited information exchange. To optimize the performance of the proposed solution, we also determine the optimal bandwidth utilization that maximizes the newly-defined criterion termed as 'safe range,' an important figure-of-merit in vehicular safety applications. Simulation results confirm the clear advantages of our proposal over the available approaches in terms of safety range, packet reception rate, end-to-end delay and BSM int

关键词： Basic safety message distributed algorithm Hidden terminals Interference Space-division multiple access Vehicular ad hoc network

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Optimization of the distributed K-means Clustering algorithm Based on Set Pair Analysis

Optimization of the Distributed K-means Clustering Algorithm...

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International Congress on Image and Signal Processing

作者： Song Ling Qi Yunfeng School of Computer & Electronic Information Guangxi University

ISBN: (纸本)9781467390996

The distributed K-means cluster algorithm which focused on multidimensional data has been widely used. However, the current distributed K-means clustering algorithm uses the Euclidean distance as the similarity degree comparison of multidimensional data, which makes the algorithm divides the data set relatively stiff. Aiming at this problem, we present a distributed k-means clustering algorithm (SPAB-DKMC) based on the method of set pair analysis. The results of experiments on the Hadoop distributed platform show that SPAB-DKMC can reduce the number of iterations and improve the efficiency of the distributed K-means clustering algorithm.

关键词： K-means clustering distributed algorithm Set pair analysis Similarity degree computation MapReduce model distributed algorithms Clustering algorithms Distribute Euclidean distance Matched-Pair Analysis algorithms Pairing iterative methods

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A distributed Downlink Resource Allocation algorithm for Dense Small Cell Networks

A Distributed Downlink Resource Allocation Algorithm for Den...

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International Conference on Wireless Communications and Signal Processing

作者： Lin Cheng Jun Zheng Jie Xiao National Mobile Communications Research Laboratory Southeast University

ISBN: (纸本)9781467376884

This paper considers the dynamic downlink spectrum resource allocation problem in dense small cell networks. To address the problem, we propose a distributed downlink resource allocation (DDRA) algorithm, which allows each base station to perform resource allocation for its users in a distributed manner. To support the DDRA algorithm, each base station needs to maintain a couple of interference tables, SITable and WITable, which are used to store those base stations that have a strong interference and a weak interference to each user in the corresponding cell in each timeslot, respectively. Meanwhile, it also needs to maintain a couple of resource status tables, SRSTable and WRSTable, which are used to store the RBs that have been allocated by those base stations contained in the SITable and WITable in each timeslot, respectively. Based on the resource status tables, each base station performs resource block (RB) allocation for its users. For each new user, those RBs that would cause a strong interference are not considered in allocation. Only those RBs that would not cause any interference or only cause a weak interference are considered. Simulation results show that the proposed DDRA algorithm can significantly increase the system capacity as compared to an existing resource allocation algorithm.

关键词： distributed algorithm Downlink Resource allocation Small cell network

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A distributed frequent itemset mining algorithm based on Spark

A distributed frequent itemset mining algorithm based on Spa...

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International Conference on Computer Supported Cooperative Work in Design

作者： Feng Gui Yunlong Ma Feng Zhang Min Liu Fei Li Weiming Shen Hua Bai School of Electronic and Information Engineering Tongji University Shanghai China

ISBN: (纸本)9781479985418

Frequent itemset mining is an important step of association rules mining. Traditional frequent itemset mining algorithms have certain limitations. For example Apriori algorithm has to scan the input data repeatedly, which leads to high I/O load and low performance, and the FP-Growth algorithm is limited by the capacity of computer's inner stores because it needs to build a FP-tree and mine frequent itemset on the basis of the FP-tree in memory. With the coming of the Big Data era, these limitations are becoming more prominent when confronted with mining large-scale data. In this paper, DPBM, a distributed matrix-based pruning algorithm based on Spark, is proposed to deal with frequent itemset mining. DPBM can greatly reduce the amount of candidate itemset by introducing a novel pruning technique for matrix-based frequent itemset mining algorithm, an improved Apriori algorithm which only needs to scan the input data once. In addition, each computer node reduces greatly the memory usage by implementing DPBM under a latest distributed environment-Spark, which is a lightning-fast distributed computing. The experimental results show that DPBM have better performance than MapReduce-based algorithms for frequent itemset mining in terms of speed and scalability.

关键词： MapReduce Spark distributed algorithm frequent itemset mining matrix-pruning mining distributed algorithms algorithms Distribute

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Hierarchical dispatch using two-stage optimisation for electricity markets in smart grid

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INTERNATIONAL JOURNAL OF SYSTEMS SCIENCE 2016年第15期47卷 3529-3536页

作者： Yang, Jie Zhang, Guoshan Ma, Kai Yanshan Univ Sch Elect Engn Dept Elect Power Engn Qinhuangdao Peoples R China Tianjin Univ Dept Automat Sch Elect Engn & Automat Tianjin 300072 Peoples R China

This paper proposes a hierarchical dispatch method for the electricity markets consisting of wholesale markets and retail markets. In the wholesale markets, the generators and the retailers decide the generation and the purchase according to the market-clearing price. In the retail markets, the retailers set the retail price to adjust the electricity consumption of the consumers. Due to the two-way communications in smart grid, the retailers can decide the electricity purchase from the wholesale markets based on the information on electricity usage of consumers in the retail markets. We establish the hierarchical dispatch model for the wholesale markets and the retail markets and develop distributed algorithms to search for the optimal generation, purchase, and consumption. Numerical results show the balance between the supply and demand, the profits of the retailers, and the convergence of the distributed algorithms.

关键词： Convex optimisation distributed algorithm economic dispatch electricity markets smart grid

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A distributed Auction-Based algorithm for the Nonconvex Economic Dispatch Problem

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IEEE TRANSACTIONS ON INDUSTRIAL INFORMATICS 2014年第2期10卷 1124-1132页

作者： Binetti, Giulio Davoudi, Ali Naso, David Turchiano, Biagio Lewis, Frank L. Polytech Bari I-70125 Bari Italy Univ Texas Arlington Arlington TX 76015 USA

This paper presents a distributed algorithm based on auction techniques and consensus protocols to solve the nonconvex economic dispatch problem. The optimization problem of the nonconvex economic dispatch includes several constraints such as valve-point loading effect, multiple fuel option, and prohibited operating zones. Each generating unit locally evaluates quantities used as bids in the auction mechanism. These units send their bids to their neighbors in a communication graph that supports the power system and which provides the required information flow. A consensus procedure is used to share the bids among the network agents and resolves the auction. As a result, the power distribution of generating units is updated and the generation cost is minimized. The effectiveness of this approach is demonstrated by simulations on standard test systems.

关键词： Auction algorithm distributed algorithm economic dispatch (ED) nonconvex optimization smart grid

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An Energy-Efficient distributed Cut Vertex Detection algorithm for Wireless Sensor Networks

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COMPUTER JOURNAL 2014年第12期57卷 1852-1869页

作者： Dagdeviren, Orhan Akram, Vahid Khalilpour Ege Univ Int Comp Inst TR-35100 Izmir Turkey

Maintaining connectivity is a very important objective of wireless sensor networks (WSNs) in successfully achieving data collection for applications. A cut vertex (node) is defined as a critical vertex whose removal disconnects a network component and partially disables data delivery. Hence, it is crucial that cut vertices be detected and treated with caution. In this paper, we propose an energy-efficient cut vertex detection (CVD) algorithm for WSNs. Our algorithm uses a depth-first search approach and is completely distributed. It benefits from the radio multicast capabilities of sensor nodes and is the first algorithm with a time complexity of O(N) and a sent message complexity of O(N), in which each message is O(log(2)(N)) bits. We show the operation of the algorithm, analyze it in detail, provide testbed experiments and extensive simulations. We compare our proposed algorithm with the other CVD algorithms and show that our algorithm saves up to 6.8 times more energy in less time.

关键词： wireless sensor networks cut vertex detection distributed algorithm energy-efficient algorithm design

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distributed location model and algorithm with position uncertainty

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The Journal of China Universities of Posts and Telecommunications 2014年第2期21卷 48-56页

作者： SHI Yu-long CUI Qi-me CAO Si-qi TAO Xiao-feng Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications

The localization of multiple mobile terminals （MTs） is an encouraging paradigm of applications in wireless networks. Peer-to-peer communication between MTs facilitates the cooperative localization of multiple MTs. For sake of low complexity and high robustness, investigations often focus on the distributed algorithm in cooperative localization. However, the impact from position uncertainty of cooperative MT lacks of analysis in related works. A new distributed location model, as well as corresponding algorithm, is devised when considering both the distance measurement error and the position uncertainty of MTs, which is more judicious than the traditional model for distributed cooperative localization scenario. In addition, the performance of proposed algorithm is analyzed through Cramér-Rao lower bound （CRLB）. Simulations indicate that the algorithm outperforms traditional methods in terms of accuracy and robustness.

关键词： distributed algorithm cooperative localization position tmcertainty

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(α,τ)-Monitoring for event detection in wireless sensor networks

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JOURNAL OF COMBINATORIAL OPTIMIZATION 2016年第4期32卷 985-1001页

作者： Bi, Ran Li, Jianzhong Gao, Hong Li, Yingshu Harbin Inst Technol Sch Comp Sci & Technol Harbin 150001 Peoples R China Georgia State Univ Dept Comp Sci Atlanta GA 30303 USA

Detecting abnormal events is one of the fundamental issues in wireless sensor networks (WSNs). In this paper, we investigate(,)-monitoring in WSNs. For a given monitored threshold, we prove that (i) the tight upper bound ofPr[S(t)=]isO(exp{-nl(/nsup,(t)/nsup)}), if(t)<;and (ii) the tight upper bound ofPr[S(t)=]isO(exp{-nl(/nsup,(t)/nsup)}), if(t)>, wherePr[X]is the probability of random eventX,S(t)is the sum of the monitored area at timet,nis the number of the sensor nodes,supis the upper bound of sensed data,(t)is the expectation ofS(t), andl(x1,x2)=x1ln(x1x2)+(1-x1)ln(1-x11-x2). An instant(,)-monitoring scheme is then developed based on the upper bound. Moreover, approximate continuous(,)-monitoring is investigated. We prove that the probability of false negative alarm isa, if the sample size isfor a given precision requirement, whereis thefractile of a standard normal distribution. Finally, the performance of the proposed algorithms is validated through experiments.

关键词： Monitoring distributed algorithm Sensor networks

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