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Capacity and delay in mobile cognitive networks with random way-point mobility model

AEU - International Journal of Electronics and Communications 2011年第4期65卷 288-295页

作者： Xingzhen Bai Shu Li Changjun Jiang Juan Xu Cheng Wang Lina Han The Key Laboratory of Embedded System and Service Computing Ministry of Education Tongji University Shanghai 200092 China College of Information & Electrical Engineering Shandong University of Science & Technology Qingdao 266510China

We study the throughput and delay scaling laws of the mobile cognitive network. There are n primary users and m secondary users in the primary network and the secondary network, respectively. They are distributed uniformly and independently on the surface of a unit torus, moving according to the random way-point mobility model (RWMM). The primary users have priority to access the spectrum, and do not alter their protocol in the presence of the secondary network. The secondary users opportunistically use the licensed spectrum when it remains unused. Under the improved 2-hop relay policy, we derive the constant throughput of Θ ( 1 ) per primary source–destination (S–D) pair when the radius of the preservation region r p = Θ ( 1 / m ) . The expected delay scales as Θ ( n / v ( n ) ) , where v ( n ) is the average speed of the primary nodes. Moreover, if the secondary network is denser than the primary network, i.e., m = n γ with γ > 1 , the constant throughput of Θ ( 1 ) per secondary S–D pair and the expected delay of Θ ( m / v ( m ) ) can be derived surprisingly when the radius of the avoidance region r s = Θ ( 1 / n ) and r p = Θ ( 1 / m ) , where v ( m ) is the average speed of the secondary nodes.

关键词： Throughput Delay Scaling law Cognitive networks Mobility

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A novel discrete particle swarm optimization algorithm for meta-task assignment in heterogeneous computing systems

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Microprocessors and Microsystems 2011年第1期35卷 10-17页

作者： Qinma Kang Hong He The Key Laboratory of “Embedded System and Service Computing” Ministry of Education Tongji University Shanghai 201804 PR China School of Information Engineering Shandong University at Weihai Weihai 264209 PR China

Optimal assignment of a meta-task in heterogeneous computing systems is NP-complete in the general case. Therefore, heuristic approaches must be employed to find good solutions within a reasonable time. We propose a novel discrete particle swarm optimization (DPSO) algorithm for this problem. Firstly, to make particle swarm optimization algorithm more suitable for solving task assignment problems, particles are represented as integer vectors and a new position update method is developed based on discrete domain. Secondly, an effective variable neighborhood descent algorithm is applied to emphasize exploitation. In addition, migration mechanism is introduced with the hope to escape from possible local optimum and to balance the exploration and exploitation. Computational simulations and comparisons based on a set of benchmark instances indicate that the proposed DPSO algorithm is a viable approach for the task assignment problem.

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Detecting vehicle target in SAR image with high moment

Detecting vehicle target in SAR image with high moment

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International Radar Symposium (IRS)

作者： Renzhou Gui Zhi Wang State Key Laboratory of Satellite Ocean Environment Dynamics The Key Laboratory of Embedded System and Service Computing Ministry of Eduction College of Electronics & Information Engineering Tongji University Shanghai China

Vehicle detection in SAR image is attractive field. High moments included numerous information is proposed to exploit in the field. It not only restrains Gaussian noise automatically, but also suppresses non-gaussian noise. Man-made targets in are different from the background clutter. Moreover, the influence of the shadow about man-made targets is reduced in the algorithm of high moments. We utilize high moments to avoid to analyst the complex scatter theory. By analyzing the relevent theory and practical calculated method of high order moments, we compare the difference of probability of detection between the target chip and clutter chip to achieve the goal of detection. Through processing lots of actual SAR data which is added different kinds of noise, we compare the performance between high order moments and low-order moments method.

关键词： Noise Vehicles Clutter Probability density function Object detection Graphics Moment methods

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A three-stage method to find refining schedules of crude oil operations in refinery

A three-stage method to find refining schedules of crude oil...

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IEEE International Conference on service Operations and Logistics, and Informatics, SOLI

作者： Naiqi Wu LiPing Bai MengChu Zhou School of Mechatronics Engineering Guangdong University of Technology Guangzhou China MoE Key Laboratory of Embedded System and Service Computing University of Tongji Shanghai China ECE New Jersey Institute of Technology Newark NJ USA

A short-term scheduling problem for crude oil operations is highly challenging. There lack efficient techniques and software tools for its solution. Our prior research shows that it may be solved in a hierarchical way. At the upper level, we find a realizable refining schedule to optimize concerned objectives. At the lower level, a detailed schedule is obtained to realize it. This work attempts to present a three-stage method to solve the the upper level problem from a control perspective. The first stage solves a linear programming problem to determine the maximal production rate. The second one solves a transportation problem to optimally assign crude oil types and volume to the distillers. The last one adjusts and sequences oil parcels. Consequently, the proposed method is computationally efficient. An industrial case study is presented to show the result.

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Modeling and analysis of dual-arm cluster tools for wafer fabrication with revisiting

Modeling and analysis of dual-arm cluster tools for wafer fa...

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2011 7th IEEE International Conference on Automation Science and Engineering, CASE 2011

作者： Qiao, Yan Wu, NaiQi Zhou, MengChu Department of Industrial Engineering School of Mechatronics Engineering Guangdong University of Technology Guangzhou 510006 China Key Laboratory of Embedded System and Service Computing Ministry of Education Tongji University Shanghai 200092 China Department of Electrical and Computer Engineering New Jersey Institute of Technology Newark NJ 07102-1982 United States

ISBN: (纸本)9781457717307

Some wafer fabrication processes are repeated processes, e.g. atomic layer deposition (ALD) process. For such processes, the wafers need to visit some processing modules for a number of times, which complicates the cycle time analysis. This paper studies the cycle time analysis problem for such processes. With a Petri net model, it is found that such processes contain local cycles involving only the revisiting PMs and global cycles involving both revisiting and non-revisiting PMs. The process switches between these two types of cycles such that the process never reaches a steady state. Based on this finding, the mechanism underlying such processes is revealed and analytical expressions are given for the calculation of their cycle time. Illustrative examples are presented to show the application of the proposed approach. © 2011 IEEE.

关键词： Atomic layer deposition

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Closed-form solution for cycle time of revisiting processes in single-arm cluster tool scheduling with atomic layer deposition

Closed-form solution for cycle time of revisiting processes ...

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IEEE International Conference on Networking, Sensing and Control

作者： YuXi Sun NaiQi Wu MengChu Zhou School of Mechatronics Engineering Guangdong University of Technology Guangzhou China Key Laboratory of MoE for Embedded System and Service Computing University of Tongji Shanghai China ECE Department New Jersey Institute of Technology Newark NJ USA

Atomic layer deposition (ALD) is a typical process with wafer revisiting that should be performed by cluster tools. This paper discusses the scheduling problem of single-arm cluster tools for the ALD process. In scheduling such system, the most difficult part is to schedule the revisiting process and obtain its optimal cycle time. This paper studies the revisiting process of ALD with revisiting times k = 3, 4, and 5. Analytical expressions are obtained to calculate the cycle time for the k possible schedules with k = 3, 4, and 5, respectively, so as to obtain the optimal one. In this way, the scheduling problem of such a revisiting process becomes simple and this is a significant improvement in scheduling cluster tools with wafer revisiting.

关键词： Schedules Semiconductor device modeling Robots Load modeling system recovery Color Integrated circuit modeling

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Fast adaptive interpolation filter algorithm for bi-predicted frame in video coding

Fast adaptive interpolation filter algorithm for bi-predicte...

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International Conference on Multimedia Technology

作者： Huichao Gao Feng Cen Weisheng Xu Key Laboratory of Embedded System and Service Computing Ministry of Education University of Tongji Shanghai China College of Electronics and Information Engineering University of Tongji Shanghai China

ISBN: (纸本)9781612847719

This paper proposes a novel adaptive interpolation filter (AIF) to reduce computational complexity and bit-rate of video coding. In the proposed AIF, the filter coefficients of B frames, which are predicted from those of adjacent P frames with a novel parabolic model, are unnecessary to transmit. Experimental results show that the coding complexity is reduced by 40.22% with no penalty on coding efficiency and 1.59% bit rate reduction is achieved at low bit-rate against conventional AIF.

关键词： Interpolation Wiener filter Adaptive filters Encoding Information filters Complexity theory

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Asymptotic bounds on lifetime of large scale clustering UWB sensor network

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Tien Tzu Hsueh Pao/Acta Electronica Sinica 2011年第10期39卷 2263-2268+2281页

作者： Xu, Juan Fang, Yu Xu, Hua-Jie School of Electronics and Information Engineering Tongji University Shanghai 200092 China Key Laboratory of Embedded System and Service Computing of the Ministry of Education Tongji University Shanghai 200092 China School of Computer and Electronic Information Guangxi University Nanning Guangxi 530004 China

Considering time hopping impulse radio ultra wide band (TH-IR UWB) sensor networks composed n sensor nodes which are placed according to a Poisson point process on a square and a Sink. The results demonstrate that the bounds on the lifetime of dense network increase with the increase of the number of nodes n, and that of extended network decrease with the increase of the number of nodes n. The results also indicate the bounds on the lifetime of clustering sensor networks is far more than that of non-clustering network, thus clustering can evidently improve network lifetime. Furthermore, the bounds on the lifetime of clustering TH-IR UWB sensor network which the nodes are distributed according to a Poisson point process are different from that of clustering network which the nodes are placed according to uniform distribution, thus the behavior of nodes deploying can remarkably affect the lifetime bound.

关键词： Energy dissipation

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Adaptive social network construction using Gaussian mixture model

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Information Technology Journal 2011年第12期10卷 2252-2259页

作者： Guo, Xin Xiang, Yang Chen, Qian Wei, Wei Department of Computer Science and Technology School of Electronic and Information Engineering Tongji University Shanghai 201804 China Key Laboratory of Embedded System and Service Computing Ministry of Education Tongji University Shanghai 200092 China

A Social network graph shows social interactions and relationships between individuals in a specific social environment, which is very helpful for analyzing social relationships, activities, structures, etc. The author quantized the strengths of social objects' relationships in social environment using an improved vector space model. Gaussian mixture model was employed to set the threshold for identifying social relationships adaptively and divide social subgroups automatically. According to the threshold, social network graph would be constructed based on performance measures. It is concluded that hidden social relationships can be discovered effectively by using this approach which is very flexible and adaptive for dynamic information feedback mechanism. © 2011 Asian Network for Scientific Information.

关键词： Gaussian distribution

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StressBar: A system for stress information collection 11

StressBar: A system for stress information collection

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2nd Wireless Health Conference, WH'11

作者： Lu, Dajun Zhan, Guoxing Wang, Shinan Shi, Weisong Wiholm, Clairy Arnetz, Bengt B. Dept. of Computer Science Wayne State University United States Dept. of Public Health and Caring Sciences Uppsala University Sweden Dept. of Family Medicine and Public Health Sciences Wayne State University Detroit MI United States Key Laboratory of Embedded System and Service Computing Tongji University Shanghai China

ISBN: (纸本)9781450309820

The causes of stress and how it affects our behaviors are generally not well understood. The stress research usually requires a large amount of data to analyze possible stress-related factors. The data collection process traditionally is time-consuming and cost-ineffective. To help medical researchers collect the stress information, we propose a tool named StressBar utilizing the powerful data collection capacity of smart phones. In this paper, we will show our design and implementation considerations of StressBar. Copyright 2011 ACM.

关键词： Smartphones

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