Journal of Electrical and Computer Engineering http://www.hindawi.com The latest articles from Hindawi Publishing Corporation © 2016 , Hindawi Publishing Corporation . All rights reserved. A Game for Energy-Aware Allocation of Virtualized Network Functions Thu, 11 Feb 2016 17:18:21 +0000 http://www.hindawi.com/journals/jece/2016/4067186/ Network Functions Virtualization (NFV) is a network architecture concept where network functionality is virtualized and separated into multiple building blocks that may connect or be chained together to implement the required services. The main advantages consist of an increase in network flexibility and scalability. Indeed, each part of the service chain can be allocated and reallocated at runtime depending on demand. In this paper, we present and evaluate an energy-aware Game-Theory-based solution for resource allocation of Virtualized Network Functions (VNFs) within NFV environments. We consider each VNF as a player of the problem that competes for the physical network node capacity pool, seeking the minimization of individual cost functions. The physical network nodes dynamically adjust their processing capacity according to the incoming workload, by means of an Adaptive Rate (AR) strategy that aims at minimizing the product of energy consumption and processing delay. On the basis of the result of the nodes’ AR strategy, the VNFs’ resource sharing costs assume a polynomial form in the workflows, which admits a unique Nash Equilibrium (NE). We examine the effect of different (unconstrained and constrained) forms of the nodes’ optimization problem on the equilibrium and compare the power consumption and delay achieved with energy-aware and non-energy-aware strategy profiles. Roberto Bruschi, Alessandro Carrega, and Franco Davoli Copyright © 2016 Roberto Bruschi et al. All rights reserved. A Processor-Sharing Scheduling Strategy for NFV Nodes Thu, 04 Feb 2016 13:10:08 +0000 http://www.hindawi.com/journals/jece/2016/3583962/ The introduction of the two paradigms SDN and NFV to “softwarize” the current Internet is making management and resource allocation two key challenges in the evolution towards the Future Internet. In this context, this paper proposes Network-Aware Round Robin (NARR), a processor-sharing strategy, to reduce delays in traversing SDN/NFV nodes. The application of NARR alleviates the job of the Orchestrator by automatically working at the intranode level, dynamically assigning the processor slices to the virtual network functions (VNFs) according to the state of the queues associated with the output links of the network interface cards (NICs). An extensive simulation set is presented to show the improvements achieved with respect to two more processor-sharing strategies chosen as reference. Giuseppe Faraci, Alfio Lombardo, and Giovanni Schembra Copyright © 2016 Giuseppe Faraci et al. All rights reserved. Application of Artificial Intelligence Techniques for the Control of the Asynchronous Machine Wed, 20 Jan 2016 07:57:07 +0000 http://www.hindawi.com/journals/jece/2016/8052027/ The induction machine is experiencing a growing success for two decades by gradually replacing the DC machines and synchronous in many industrial applications. This paper is devoted to the study of advanced methods applied to the command of the asynchronous machine in order to obtain a system of control of high performance. While the criteria for response time, overtaking, and static error can be assured by the techniques of conventional control, the criterion of robustness remains a challenge for researchers. This criterion can be satisfied only by applying advanced techniques of command. After mathematical modeling of the asynchronous machine, it defines the control strategies based on the orientation of the rotor flux. The results of the different simulation tests highlight the properties of robustness of algorithms proposed and suggested to compare the different control strategies. F. Khammar and N. E. Debbache Copyright © 2016 F. Khammar and N. E. Debbache. All rights reserved. Restoration of Partial Blurred Image Based on Blur Detection and Classification Wed, 13 Jan 2016 13:13:17 +0000 http://www.hindawi.com/journals/jece/2016/2374926/ A new restoration algorithm for partial blurred image which is based on blur detection and classification is proposed in this paper. Firstly, a new blur detection algorithm is proposed to detect the blurred regions in the partial blurred image. Then, a new blur classification algorithm is proposed to classify the blurred regions. Once the blur class of the blurred regions is confirmed, the structure of the blur kernels of the blurred regions is confirmed. Then, the blur kernel estimation methods are adopted to estimate the blur kernels. In the end, the blurred regions are restored using nonblind image deblurring algorithm and replace the blurred regions in the partial blurred image with the restored regions. The simulated experiment shows that the proposed algorithm performs well. Dong Yang and Shiyin Qin Copyright © 2016 Dong Yang and Shiyin Qin. All rights reserved. A Novel WLAN Roaming Decision and Selection Scheme for Mobile Data Offloading Tue, 29 Dec 2015 11:37:28 +0000 http://www.hindawi.com/journals/jece/2015/324936/ The existing IEEE and 3GPP standards have laid the foundation for integrating cellular and WiFi network to deliver a seamless experience for the end-users when roaming across multiple access networks. However, in recent studies, the issue of making roaming decision and intelligently selecting the most preferable Point of Service to optimize network resource and improve end user’s experience has not been considered properly. In this paper, we propose a novel cellular and WiFi roaming decision and AP selection scheme based on state of the art, 3GPP TS24.312 and IEEE 802.11u, k standards. Our proposed scheme assists the mobile nodes to decide the right timing to make roaming decision and select preferable point of service based on the operator’s policies and real-time network condition. We also introduce our simulation model of a heterogeneous network with cellular and WiFi interworking as well as 3GPP ANDSF, TS24.312. It is a complete end-to-end system model from application to physical layer with considering user’s mobility and realistic traffic model. The proposed scheme outperformed the conventional WiFi selection scheme in terms of dynamically steering mobile node’s data traffic from macrocell to available Access Points. The proposed scheme increased the utilization and balanced the traffic load of access points and improved user’s experienced throughput. Nam Nguyen, Mohammad Arifuzzaman, and Takuro Sato Copyright © 2015 Nam Nguyen et al. All rights reserved. Cooperative Cloud Service Aware Mobile Internet Coverage Connectivity Guarantee Protocol Based on Sensor Opportunistic Coverage Mechanism Tue, 29 Dec 2015 09:27:55 +0000 http://www.hindawi.com/journals/jece/2015/128691/ In order to improve the Internet coverage ratio and provide connectivity guarantee, based on sensor opportunistic coverage mechanism and cooperative cloud service, we proposed the coverage connectivity guarantee protocol for mobile Internet. In this scheme, based on the opportunistic covering rules, the network coverage algorithm of high reliability and real-time security was achieved by using the opportunity of sensor nodes and the Internet mobile node. Then, the cloud service business support platform is created based on the Internet application service management capabilities and wireless sensor network communication service capabilities, which is the architecture of the cloud support layer. The cooperative cloud service aware model was proposed. Finally, we proposed the mobile Internet coverage connectivity guarantee protocol. The results of experiments demonstrate that the proposed algorithm has excellent performance, in terms of the security of the Internet and the stability, as well as coverage connectivity ability. Qin Qin, Yong-qiang He, and Li-ming Nie Copyright © 2015 Qin Qin et al. All rights reserved. Modeling and Simulation of Power Distribution System in More Electric Aircraft Sun, 27 Dec 2015 11:05:49 +0000 http://www.hindawi.com/journals/jece/2015/847624/ The More Electric Aircraft concept is a fast-developing trend in modern aircraft industry. With this new concept, the performance of the aircraft can be further optimized and meanwhile the operating and maintenance cost will be decreased effectively. In order to optimize the power system integrity and have the ability to investigate the performance of the overall system in any possible situations, one accurate simulation model of the aircraft power system will be very helpful and necessary. This paper mainly introduces a method to build a simulation model for the power distribution system, which is based on detailed component models. The power distribution system model consists of power generation unit, transformer rectifier unit, DC-DC converter unit, and DC-AC inverter unit. In order to optimize the performance of the power distribution system and improve the quality of the distributed power, a feedback control network is designed based on the characteristics of the power distribution system. The simulation result indicates that this new simulation model is well designed and it works accurately. Moreover, steady state performance and transient state performance of the model can fulfill the requirements of aircraft power distribution system in the realistic application. Zhangang Yang, Junchao Qu, Yingchuan Ma, and Xudong Shi Copyright © 2015 Zhangang Yang et al. All rights reserved. Short-Term Load Forecasting Based on Wavelet Transform and Least Squares Support Vector Machine Optimized by Fruit Fly Optimization Algorithm Wed, 16 Dec 2015 08:56:14 +0000 http://www.hindawi.com/journals/jece/2015/862185/ Electric power is a kind of unstorable energy concerning the national welfare and the people’s livelihood, the stability of which is attracting more and more attention. Because the short-term power load is always interfered by various external factors with the characteristics like high volatility and instability, a single model is not suitable for short-term load forecasting due to low accuracy. In order to solve this problem, this paper proposes a new model based on wavelet transform and the least squares support vector machine (LSSVM) which is optimized by fruit fly algorithm (FOA) for short-term load forecasting. Wavelet transform is used to remove error points and enhance the stability of the data. Fruit fly algorithm is applied to optimize the parameters of LSSVM, avoiding the randomness and inaccuracy to parameters setting. The result of implementation of short-term load forecasting demonstrates that the hybrid model can be used in the short-term forecasting of the power system. Wei Sun and Minquan Ye Copyright © 2015 Wei Sun and Minquan Ye. All rights reserved. Cooperative Optimization QoS Cloud Routing Protocol Based on Bacterial Opportunistic Foraging and Chemotaxis Perception for Mobile Internet Tue, 15 Dec 2015 09:36:38 +0000 http://www.hindawi.com/journals/jece/2015/641062/ In order to strengthen the mobile Internet mobility management and cloud platform resources utilization, optimizing the cloud routing efficiency is established, based on opportunistic bacterial foraging bionics, and puts forward a chemotaxis perception of collaborative optimization QoS (Quality of Services) cloud routing mechanism. The cloud routing mechanism is based on bacterial opportunity to feed and bacterial motility and to establish the data transmission and forwarding of the bacterial population behavior characteristics. This mechanism is based on the characteristics of drug resistance of bacteria and the structure of the field, and through many iterations of the individual behavior and population behavior the bacteria can be spread to the food gathering area with a certain probability. Finally, QoS cloud routing path would be selected and optimized based on bacterial bionic optimization and hedge mapping relationship between mobile Internet node and bacterial population evolution iterations. Experimental results show that, compared with the standard dynamic routing schemes, the proposed scheme has shorter transmission delay, lower packet error ratio, QoS cloud routing loading, and QoS cloud route request overhead. Shujuan Wang, Long He, and Guiru Cheng Copyright © 2015 Shujuan Wang et al. All rights reserved. Efficient Cross-Layer Optimization Algorithm for Data Transmission in Wireless Sensor Networks Thu, 10 Dec 2015 09:58:58 +0000 http://www.hindawi.com/journals/jece/2015/545798/ In this paper, we address the problems of joint design for channel selection, medium access control (MAC), signal input control, and power control with cooperative communication, which can achieve tradeoff between optimal signal control and power control in wireless sensor networks (WSNs). The problems are solved in two steps. Firstly, congestion control and link allocation are separately provided at transport layer and network layer, by supply and demand based on compressed sensing (CS). Secondly, we propose the cross-layer scheme to minimize the power cost of the whole network by a linear optimization problem. Channel selection and power control scheme, using the minimum power cost, are presented at MAC layer and physical layer, respectively. These functions interact through and are regulated by congestion rate so as to achieve a global optimality. Simulation results demonstrate the validity and high performance of the proposed algorithm. Chengtie Li, Jinkuan Wang, and Mingwei Li Copyright © 2015 Chengtie Li et al. All rights reserved. Performance Analysis of Precoded MIMO PLC System Based on Two-Sided Jacobi SVD Tue, 08 Dec 2015 09:07:16 +0000 http://www.hindawi.com/journals/jece/2015/706526/ This paper evaluates the performance of closed loop multiple input multiple output power line communication (CL MIMO PLC) system based on enhanced zero-forcing (ZF) equalizer. In this work, the two-sided Jacobi (TSJ) algorithm has been investigated for the computation of singular value decomposition of the channel matrix. Quantized parameters are feedback from the receiver to the transmitter for precoding process. Numerous simplifications are introduced for the reduction of the algorithm complexity. The performance of the CL MIMO PLC is evaluated in terms of bit error rate (BER), constellation error vector magnitude (EVM), and mean square error (MSE) between the constructed SVD matrices and Matlab computed ones. Hasna Kilani, Mohamed Tlich, and Rabah Attia Copyright © 2015 Hasna Kilani et al. All rights reserved. A Movement-Efficient Deployment Scheme Based on Information Coverage for Mobile Sensor Networks Thu, 03 Dec 2015 13:09:18 +0000 http://www.hindawi.com/journals/jece/2015/986956/ Covering the surveillance region is a key task for wireless sensor networks. For mobile sensors, the deployment of sensors at appropriate locations is the key issue for sufficient coverage of surveillance area, and efficient resource management of sensor network. Previous studies most utilize physical coverage model for developing deployment schemes, in that the sensor resources may be wasted during the deployment for coverage. In this paper, a novel movement-efficient deployment scheme for mobile sensor networks is proposed, which adapts the information coverage model and the classical potential field method. The performances of the proposed scheme are evaluated comparing to two other schemes in aspects of coverage rate, coverage hole rate, ideal moving distance, and actual moving distance through extensive simulations. Simulation results show that the proposed scheme performs better than these related schemes in both coverage and movement efficiency. Wei Cheng, Yong Li, Yi Jiang, and Xipeng Yin Copyright © 2015 Wei Cheng et al. All rights reserved. Novel Spatiotemporal Filter for Dim Point Targets Detection in Infrared Image Sequences Wed, 02 Dec 2015 11:55:12 +0000 http://www.hindawi.com/journals/jece/2015/923469/ Dim point target detection is of great importance in both civil and military fields. In this paper a novel spatiotemporal filter is proposed to incorporate both the spatial and temporal features of moving dim point targets. Since targets are expected to be detected as far as possible, in this situation, they have no texture features in spatial dimensions, appearing like isolated points. Based on the attributes, potential targets are extracted by searching the local maximum point in a sliding window. And the potential targets are then correlated based on target moving patterns. After combining local maximum points and target moving patterns, structure background in infrared scene is removed. Next, the temporal profiles of infrared sense are reviewed and examined. By a new max-median filter performing on temporal profiles, the intensity of target pulse signal is extracted. Finally, each temporal profile is divided into several pieces to estimate the variance of the temporal profiles, which leads to a new detection metric. The proposed approach is tested via several infrared image sequences. The results show that our proposed method can significantly reduce the complex background in aerial infrared image sequence and have a good detection performance. Zhaohui Li, Xiaorui Wang, Jianqi Zhang, and Delian Liu Copyright © 2015 Zhaohui Li et al. All rights reserved. Diagnosis of Elevator Faults with LS-SVM Based on Optimization by K-CV Wed, 02 Dec 2015 07:36:17 +0000 http://www.hindawi.com/journals/jece/2015/935038/ Several common elevator malfunctions were diagnosed with a least square support vector machine (LS-SVM). After acquiring vibration signals of various elevator functions, their energy characteristics and time domain indicators were extracted by theoretically analyzing the optimal wavelet packet, in order to construct a feature vector of malfunctions for identifying causes of the malfunctions as input of LS-SVM. Meanwhile, parameters about LS-SVM were optimized by K-fold cross validation (K-CV). After diagnosing deviated elevator guide rail, deviated shape of guide shoe, abnormal running of tractor, erroneous rope groove of traction sheave, deviated guide wheel, and tension of wire rope, the results suggested that the LS-SVM based on K-CV optimization was one of effective methods for diagnosing elevator malfunctions. Zhou Wan, Shilin Yi, Kun Li, Ran Tao, Min Gou, Xinshi Li, and Shu Guo Copyright © 2015 Zhou Wan et al. All rights reserved. A Scaling Scheme for DCT Precoded Optical Intensity-Modulated Direct Detection Systems Sun, 29 Nov 2015 10:56:05 +0000 http://www.hindawi.com/journals/jece/2015/367693/ A scaling technique is employed to improve the performance of a Discrete Cosine Transform (DCT) precoded optical intensity-modulated direct detection (IM/DD) OFDM system, which fully exploits the dynamic range of a digital-to-analog converter (DAC). The theoretical analysis shows that the proposed scaling scheme can improve the BER performance of DCT precoded and scaled OFDM systems. The experiment results also show that the proposed scheme significantly improves the BER performance without changing the receiver structure. The measured received sensitivity at a BER of 10−3 for a 4 G samples/s (2.7 Gbits/s) DCT precoded and scaled OFDM signal and after 100 km standard single-mode fiber (SMF) transmission has been improved by 3 and 1.3 dB when compared with the original OFDM system and conventional DCT precoded OFDM system, respectively. Zhongpeng Wang, Xiumin Wang, Fangni Chen, Weiwei Qiu, and Linpeng Ye Copyright © 2015 Zhongpeng Wang et al. All rights reserved. DOA Estimation Based on Sparse Signal Recovery Utilizing Double-Threshold Sigmoid Penalty Thu, 26 Nov 2015 11:59:02 +0000 http://www.hindawi.com/journals/jece/2015/287915/ This paper proposes a new algorithm based on sparse signal recovery for estimating the direction of arrival (DOA) of multiple sources. The problem model we build is about the sample covariance matrix fitting by unknown source powers. We enhance the sparsity by the double-threshold sigmoid penalty function which can approximate the norm accurately. Our method can distinguish closely spaced sources and does not need the knowledge of the number of the sources. In addition, our method can also perform well in low SNR. Besides, our method can handle more sources accurately than other methods. Simulations are done to certify the great performance of the proposed method. Hanbing Wang, Hui Li, and Bin Li Copyright © 2015 Hanbing Wang et al. All rights reserved. User Utility Oriented Queuing Model for Resource Allocation in Cloud Environment Thu, 19 Nov 2015 08:53:37 +0000 http://www.hindawi.com/journals/jece/2015/246420/ Resource allocation is one of the most important research topics in servers. In the cloud environment, there are massive hardware resources of different kinds, and many kinds of services are usually run on virtual machines of the cloud server. In addition, cloud environment is commercialized, and economical factor should also be considered. In order to deal with commercialization and virtualization of cloud environment, we proposed a user utility oriented queuing model for task scheduling. Firstly, we modeled task scheduling in cloud environment as an //1 queuing system. Secondly, we classified the utility into time utility and cost utility and built a linear programming model to maximize total utility for both of them. Finally, we proposed a utility oriented algorithm to maximize the total utility. Massive experiments validate the effectiveness of our proposed model. Zhe Zhang and Ying Li Copyright © 2015 Zhe Zhang and Ying Li. All rights reserved. A Genetic Algorithm Based Minimal Maximal Load Tree Routing Algorithm in Wireless Sensor Networks Sun, 08 Nov 2015 13:33:16 +0000 http://www.hindawi.com/journals/jece/2015/258343/ The key issue of static routing algorithms is how to construct an energy efficient routing tree that is utilized during the whole network duration in order to extend network lifetime. In this paper, we have illuminated that, in applications that define network lifetime as the time when the first sensor dies, the optimal routing tree should be the routing tree with minimal maximal load of all sensors and named such trees the Minimal Maximal Load Tree (MMLT). Since the procedure of constructing a routing tree is complex and the number of possible routing trees in a network is very huge, we have proposed a genetic algorithm (GA) based algorithm to obtain approximate Minimal Maximal Load Tree (MMLT). Each individual corresponds to a routing tree, and the fitness function is defined as the maximal load of all sensors in accordance with the routing tree that the individual corresponds to. Thus, approximate MMLT is obtained and network lifetime is extended. Simulation results show that our proposed algorithm notably extends network lifetime. Zhi Huang Copyright © 2015 Zhi Huang. All rights reserved. Compressed Sensing MRI Reconstruction Algorithm Based on Contourlet Transform and Alternating Direction Method Wed, 04 Nov 2015 11:45:25 +0000 http://www.hindawi.com/journals/jece/2015/175231/ Compressed sensing (CS) based methods have recently been used to reconstruct magnetic resonance (MR) images from undersampled measurements, which is known as CS-MRI. In traditional CS-MRI, wavelet transform can hardly capture the information of image curves and edges. In this paper, we present a new CS-MRI reconstruction algorithm based on contourlet transform and alternating direction method (ADM). The MR images are firstly represented by contourlet transform, which can describe the images’ curves and edges fully and accurately. Then the MR images are reconstructed by ADM, which is an effective CS reconstruction method. Numerical results validate the superior performance of the proposed algorithm in terms of reconstruction accuracy and computation time. Zhenyu Hu, Qiuye Wang, Congcong Ming, Lai Wang, Yuanqing Hu, and Jian Zou Copyright © 2015 Zhenyu Hu et al. All rights reserved. The Routing Algorithm Based on Fuzzy Logic Applied to the Individual Physiological Monitoring Wearable Wireless Sensor Network Mon, 02 Nov 2015 08:57:17 +0000 http://www.hindawi.com/journals/jece/2015/546425/ In recent years, the research of individual wearable physiological monitoring wireless sensor network is in the primary stage. The monitor of physiology and geographical position used in wearable wireless sensor network requires performances such as real time, reliability, and energy balance. According to these requirements, this paper introduces a design of individual wearable wireless sensor network monitoring system; what is more important, based on this background, this paper improves the classical Collection Tree Protocol and puts forward the improved routing protocol F-CTP based on the fuzzy logic routing algorithm. Simulation results illustrate that, with the F-CTP protocol, the sensor node can transmit data to the sink node in real time with higher reliability and the energy of the nodes consumes balance. The sensor node can make full use of network resources reasonably and prolong the network life. Jie Jiang, Yun Liu, Fuxing Song, Ronghao Du, and Mengsen Huang Copyright © 2015 Jie Jiang et al. All rights reserved. Regression Cloud Models and Their Applications in Energy Consumption of Data Center Mon, 19 Oct 2015 13:29:02 +0000 http://www.hindawi.com/journals/jece/2015/143071/ As cloud data center consumes more and more energy, both researchers and engineers aim to minimize energy consumption while keeping its services available. A good energy model can reflect the relationships between running tasks and the energy consumed by hardware and can be further used to schedule tasks for saving energy. In this paper, we analyzed linear and nonlinear regression energy model based on performance counters and system utilization and proposed a support vector regression energy model. For performance counters, we gave a general linear regression framework and compared three linear regression models. For system utilization, we compared our support vector regression model with linear regression and three nonlinear regression models. The experiments show that linear regression model is good enough to model performance counters, nonlinear regression is better than linear regression model for modeling system utilization, and support vector regression model is better than polynomial and exponential regression models. Yanshuang Zhou, Na Li, Hong Li, and Yongqiang Zhang Copyright © 2015 Yanshuang Zhou et al. All rights reserved. Optimal Contract Design for Cooperative Relay Incentive Mechanism under Moral Hazard Mon, 19 Oct 2015 12:47:17 +0000 http://www.hindawi.com/journals/jece/2015/690807/ Cooperative relay can effectively improve spectrum efficiency by exploiting the spatial diversity in the wireless networks. However, wireless nodes may acquire different network information with various users’ location and mobility, channels’ conditions, and other factors, which results in asymmetric information between the source and the relay nodes (RNs). In this paper, the relay incentive mechanism between relay nodes and the source is investigated under the asymmetric information. By modelling multiuser cooperative relay as a labour market, a contract model with moral hazard for relay incentive is proposed. To effectively incentivize the potential RNs to participate in cooperative relay, the optimization problems are formulated to maximize the source’s utility while meeting the feasible conditions under both symmetric and asymmetric information scenarios. Numerical simulation results demonstrate the effectiveness of the proposed contract design scheme for cooperative relay. Nan Zhao, Minghu Wu, Wei Xiong, and Cong Liu Copyright © 2015 Nan Zhao et al. All rights reserved. New Method of Image Background Suppression Based on Soft Morphology and Retinex Theory Sun, 18 Oct 2015 09:02:42 +0000 http://www.hindawi.com/journals/jece/2015/389487/ A new river flow measurement method based on graphic process has been proposed recently, which gets the velocity in optical imaging modality through measuring the continuous displacement of floating debris, then reconstructs a two-dimensional river surface velocity field by using the velocity of floating debris, and computes the section flow at last. However, the surface optical images have not only lights of target information, but also surface optical noise. It is difficult for reliable and stable continuous displacement detection of complex small observation target, which occupies only a small number of pixels comparing to a large field imaging area and has complex optical reflection properties. To solve this problem, this paper presents a background suppression method based on soft morphology and Retinex theory. Soft morphology is firstly used for the opening operation of the image, and then Retinex theory is used for optimal estimation of image incident component to suppress background of image. Finally, the simulations show that our method is superior to gray morphology and soft morphology on the performance of targets enhancement, noise filtering, and background suppression, and it has better background and targets discrimination quality subjective evaluation and higher signal-to-clutter ratio. Lili Zhang, Tanghuai Fan, Xin Wang, Cheng Kong, and Xijun Yan Copyright © 2015 Lili Zhang et al. All rights reserved. Crowd Motion Analysis Based on Social Force Graph with Streak Flow Attribute Thu, 15 Oct 2015 09:31:58 +0000 http://www.hindawi.com/journals/jece/2015/492051/ Over the past decades, crowd management has attracted a great deal of attention in the area of video surveillance. Among various tasks of video surveillance analysis, crowd motion analysis is the basis of numerous subsequent applications of surveillance video. In this paper, a novel social force graph with streak flow attribute is proposed to capture the global spatiotemporal changes and the local motion of crowd video. Crowd motion analysis is hereby implemented based on the characteristics of social force graph. First, the streak flow of crowd sequence is extracted to represent the global crowd motion; after that, spatiotemporal analogous patches are obtained based on the crowd visual features. A weighted social force graph is then constructed based on multiple social properties of crowd video. The graph is segmented into particle groups to represent the similar motion patterns of crowd video. A codebook is then constructed by clustering all local particle groups, and consequently crowd abnormal behaviors are detected by using the Latent Dirichlet Allocation model. Extensive experiments on challenging datasets show that the proposed method achieves preferable results in the application of crowd motion segmentation and abnormal behavior detection. Shaonian Huang, Dongjun Huang, and Mansoor Ahmed Khuhro Copyright © 2015 Shaonian Huang et al. All rights reserved. Modeling and Fault Diagnosis of Interturn Short Circuit for Five-Phase Permanent Magnet Synchronous Motor Wed, 07 Oct 2015 13:36:27 +0000 http://www.hindawi.com/journals/jece/2015/168786/ Taking advantage of the high reliability, multiphase permanent magnet synchronous motors (PMSMs), such as five-phase PMSM and six-phase PMSM, are widely used in fault-tolerant control applications. And one of the important fault-tolerant control problems is fault diagnosis. In most existing literatures, the fault diagnosis problem focuses on the three-phase PMSM. In this paper, compared to the most existing fault diagnosis approaches, a fault diagnosis method for Interturn short circuit (ITSC) fault of five-phase PMSM based on the trust region algorithm is presented. This paper has two contributions. (1) Analyzing the physical parameters of the motor, such as resistances and inductances, a novel mathematic model for ITSC fault of five-phase PMSM is established. (2) Introducing an object function related to the Interturn short circuit ratio, the fault parameters identification problem is reformulated as the extreme seeking problem. A trust region algorithm based parameter estimation method is proposed for tracking the actual Interturn short circuit ratio. The simulation and experimental results have validated the effectiveness of the proposed parameter estimation method. Jian-wei Yang, Man-feng Dou, and Zhi-yong Dai Copyright © 2015 Jian-wei Yang et al. All rights reserved. A Secure Privacy-Preserving Data Aggregation Model in Wearable Wireless Sensor Networks Wed, 07 Oct 2015 09:59:17 +0000 http://www.hindawi.com/journals/jece/2015/104286/ With the rapid development and widespread use of wearable wireless sensors, data aggregation technique becomes one of the most important research areas. However, the sensitive data collected by sensor nodes may be leaked at the intermediate aggregator nodes. So, privacy preservation is becoming an increasingly important issue in security data aggregation. In this paper, we propose a security privacy-preserving data aggregation model, which adopts a mixed data aggregation structure. Data integrity is verified both at cluster head and at base station. Some nodes adopt slicing technology to avoid the leak of data at the cluster head in inner-cluster. Furthermore, a mechanism is given to locate the compromised nodes. The analysis shows that the model is robust to many attacks and has a lower communication overhead. Changlun Zhang, Chao Li, and Jian Zhang Copyright © 2015 Changlun Zhang et al. All rights reserved. Priority Control Strategy of VSC-MTDC System for Integrating Wind Power Sun, 04 Oct 2015 09:03:51 +0000 http://www.hindawi.com/journals/jece/2015/347350/ For the obvious advantages in integrating wind power, multiterminal HVDC transmission system (VSC-MTDC) is widely used. The priority control strategy is proposed in this paper considering the penetration rate of wind power for the AC grid. The strategy aims to solve the problems of power allocation and DC voltage control of the DC system. The main advantage of this strategy is that the demands for wind power of different areas can be satisfied and a power reference for the wind power trade can also be provided when wind farms transmit active power to several AC grids through the DC network. The objective is that power is well distributed according to the output power of wind farm with the demand of AC system and satisfactory control performance of DC voltage is obtained. Wen-ning Yan, Ke-jun Li, Zhuo-di Wang, Xin-han Meng, and Jianguo Zhao Copyright © 2015 Wen-ning Yan et al. All rights reserved. Investigating a Mobility-Aware QoS Model for Multimedia Streaming Rate Adaptation Thu, 01 Oct 2015 09:44:31 +0000 http://www.hindawi.com/journals/jece/2015/548638/ Supporting high quality multimedia streaming on wireless devices poses several challenges compared to wired networks due to the high variance in network performance encountered in the mobile environment. Although rate adaptation is commonly used in multimedia applications to compensate for fluctuations in network performance, it is a reactive mechanism which is not aware of the frequently changing connectivity that may occur on mobile devices. This paper proposed a performance evaluation model for multimedia streaming applications that is aware of user mobility and network performance. We presented an example of mathematical solution to the model and demonstrated the functionality using common mobility and connectivity examples that may be found in an urban environment. The proposed model is evaluated based on this functionality and how it may be used to enhance application performance. Fragkiskos Sardis, Glenford Mapp, Jonathan Loo, Mahdi Aiash, and Alexey Vinel Copyright © 2015 Fragkiskos Sardis et al. All rights reserved. Cloud Platform Based on Mobile Internet Service Opportunistic Drive and Application Aware Data Mining Thu, 01 Oct 2015 06:46:08 +0000 http://www.hindawi.com/journals/jece/2015/357378/ Because the static cloud platform cannot satisfy the diversity of mobile Internet service and inefficient data mining problems, we presented a reliable and efficient data mining cloud platform construction scheme based on the mobile Internet service opportunistic driving and application perception. In this scheme, first of all data selection mechanism was established based on mobile Internet service opportunistic drive. Secondly, through the cloud platform different cloud and channel aware, nonlinear mapping from the service to a data set of proposed perceptual model is applied. Finally, on the basis of the driving characteristics and extraction of perceptual features, the cloud platform would be constructed through the service opportunities of mobile Internet applications, which could provide robust and efficient data mining services. The experimental results show that the proposed mechanism, compared to the cloud platform based on distributed data mining, has obvious advantages in system running time, memory usage, and data clustering required time, as well as average clustering quality. Ge Zhou Copyright © 2015 Ge Zhou. All rights reserved. Applying Pulse Width Modulation in Body Coupled Communication Thu, 01 Oct 2015 06:45:12 +0000 http://www.hindawi.com/journals/jece/2015/378054/ We study the application of Pulse Width Modulation (PWM) technique in Body Coupled Communication. The term Body Coupled Communication is used in order to specify that the human body or a part of it, such as an arm, is used as a path that transfers digital information. The digital information is either generated due to coupling of the body, for example, in medical equipment as a result of a measurement, or generated by external circuitry attached somewhere onto the body and is transferred to a terminal by touching it. In this paper, the latter case will be described, where, for illustration purposes, the touch of the human hand on a doorknob triggers the unlocking mechanism. Miltiadis Moralis-Pegios, Pelagia Alexandridou, and Christos Koukourlis Copyright © 2015 Miltiadis Moralis-Pegios et al. All rights reserved.