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l-SkyDiv query:Effectively improve the usefulness of skylines

Science China(Information Sciences) 2010年第9期53卷 1785-1799页

作者： HUANG ZhenHua1,2*,XIANG Yang1 & LIN ZiYu3 1Department of Computer Science and Technology,Tongji University,Shanghai 201804,China 2The key laboratory of embedded system and service computing,Ministry of Education,Tongji University,Shanghai 200092,China 3Department of Computer Science and Technology,Peking University,Beijing 100871,China 1. Department of Computer Science and Technology Tongji University Shanghai 201804 China2. The Key Laboratory of Embedded System and Service Computing Ministry of Education Tongji University Shanghai 200092 China3. Department of Computer Science and Technology Peking University Beijing 100871 China

Skyline query processing has recently received a lot of attention in database *** a set of multi-dimensional objects,the skyline query finds the objects that are not dominated by *** the best of our knowledge,the existing researches mainly focus on how to efficiently return the whole skyline ***,as the cardinality and dimensionality of input dataset increase,the number of skylines grows exponentially,and hence this "huge" skyline set is completely useless to *** by the above fact,in this paper,we present a novel type of l-SkyDiv query,which only returns l skylines having maximum diversity,to improve the usefulness of skyline ***,we prove that the l-SkyDiv query belongs to the NP-Hard problem theoretically,and propose three efficient heuristic algorithms whose time complexities are polynomial to fast implement the proposed ***,we present detailed theoretical analyses and extensive experiments,demonstrating that our algorithms are both efficient and effective.

关键词： skyline query diversity heuristic algorithm query optimization performance evaluation

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Design issues in ZigBee-based sensor network for healthcare applications

Design issues in ZigBee-based sensor network for healthcare ...

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2012 9th IEEE International Conference on Networking, Sensing and Control, ICNSC 2012

作者： Choi, Jin Soo Zhou, MengChu Department of Electrical and Computer Engineering New Jersey Institute of Technology Newark NJ 07102 United States Key Laboratory of Embedded System and Service Computing Ministry of Education Tongji University Shanghai 200092 China

ISBN: (纸本)9781467303880

IEEE 802.15.4/ZigBee sensor networks support small power consumption and node expansion compared to other network standards for WSN. Body sensor networks (BSN) require a number of sensors for sensing medical information from human body, and low power consumption to monitor a patient's status for a long time. However, ZigBee has limited bandwidth and is thus hard to support real time data transmission because of the adoption of CSMA-CA as its medium access control (MAC) protocol. In this paper, we will analyze the reasonable number of nodes, size of payload and packet interval for best QoS for such network. It is found that an appropriate MAC parameters setting can improve the QoS compared to the default setting in IEEE 802.15.4 specification. The effective data rate, average end-to-end delay and packet delivery ratio are found via simulation for various network settings. The results are useful for the construction of ZigBee networks for patient monitoring and care. © 2012 IEEE.

关键词： Medium access control

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Web service composition techniques in a health care service platform

Web service composition techniques in a health care service ...

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2011 IEEE 9th International Conference on Web services, ICWS 2011

作者： Wang, Pengwei Ding, Zhijun Jiang, Changjun Zhou, Mengchu 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 United States

ISBN: (纸本)9780769544632

The information technology has been recognized as one of the most important means to improve health care and curb its ever-increasing cost. However, existing efforts mainly focus on informatization of hospitals or medical institutions within organizations, and few are directly oriented to individuals. The strong demand for various health services from customers calls for the creation of powerful individual-oriented personalized health care service systems. Web service composition (WSC) and related technologies can greatly help one build such systems. This paper aims to present a newly developed platform called a Public-oriented Health care Information service Platform (PHISP) and several novel WSC techniques that are used to build it. Among them include WSC techniques that can well support branch and parallel structures. © 2011 IEEE.

关键词： Web services

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Petri net-based scheduling analysis of dual-arm cluster tools with wafer revisiting

Petri net-based scheduling analysis of dual-arm cluster tool...

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2012 IEEE International Conference on Automation Science and Engineering: Green Automation Toward a Sustainable Society, CASE 2012

作者： Qiao, Yan Wu, Naiqi Zhou, Mengchu Department of Industrial Engineering School of Electro-Mechanical Engineering Guangdong University of Technology Guangzhou 510006 China Key Laboratory of Embedded System and Service Computing Ministry of Education Tongji University Shanghai 200092 China

ISBN: (纸本)9781467304283

With wafer revisit, it is complicated to schedule cluster tools in semiconductor fabrication. In wafer fabrication processes, such as atomic layer deposition (ALD), the wafers need to visit some process modules for a number of times. The existing swap-based strategy can be used to operate a dual-arm cluster tool for such a process. It results in a 3-wafer cyclic schedule. However, it is not optimal in the sense of cycle time. Thus, to search for a better schedule, a Petri net model is developed for a dual-arm cluster tool with wafer revisit. With it, the properties of the 3-wafer schedule are analyzed. It is found that, to improve the performance, it is necessary to reduce the number of wafers completed in a cycle. Thus, a 1-wafer schedule is developed by using a new swap-based strategy. © 2012 IEEE.

关键词： Petri nets

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Model predictive control for HVAC systems - A review

Model predictive control for HVAC systems - A review

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2013 IEEE International Conference on Automation Science and Engineering, CASE 2013

作者： Kwadzogah, Roger Zhou, Mengchu Li, Sisi Department of Electrical and Computer Engineering New Jersey Institute of Technology Newark NJ 07013 United States Key Laboratory of Embedded System and Service Computing Ministry of Education Tongji University Shanghai 201804 China

ISBN: (纸本)9781479915156

The world faces an energy problem. Oil supply is gradually running out. Its use is polluting the planet with greenhouse gas. Most alternative energy sources also pose some environmental problems. Hence the efficient use of energy must be an integral part of any solution to them. Whenever possible, one must use advanced control engines and technologies to achieve the highest energy efficiency. In Heating Ventilation and Air Conditioning (HVAC) industry, much research has identified a number of energy-saving control methods. Derived from optimal control theory, Model Predictive Control (MPC) is one of them. This paper presents a comprehensive review of its applications to HVAC systems. © 2013 IEEE.

关键词： Model predictive control

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Construction-and-extraction based index for images retrieval

IEEJ Transactions on Electronics, Information and Systems

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IEEJ Transactions on Electronics, Information and systems 2011年第7期131卷 1377-1383页

作者： Zhang, Junqi Ni, Lina Tian, Chunqi Gao, Shangce Tang, Zheng Department of Computer Science and Technology Key Laboratory of Embedded System and Service Computing Tongji University Shanghai 200092 China College of Info Sci and Engi Shandong University of Science and Technology Qingdao 266510 China Department of Intellectual Information Systems Engineering University of Toyama Toyama-shi 930-8555 Japan

The past recent years have witnessed more and more applications on image retrieval. As searching a large image database is often costly, to improve the efficiency, high dimensional indexes may help. This paper proposes an adaptive hybrid index (AHI) supported by a construction-and-extraction technique to support image retrieval. First, the image clusters are further partitioned into sub-clusters to reduce the overlap between clusters and indexed into an iDistance index. Then, the query sampling statistically extracts some sub-cluster from the iDistance index into a sequential file. Finally, the users' queries are accurately returned by searching both the iDistance index and the sequential file. It's proved that the proposed AHI never performs worse than the sequential scan. Particularly, the experimental results demonstrate that the proposed index AHI is beneficial and achieves better performance than some exiting methods. It is about 2 times faster than iDistance, almost three times than Omni-sequential, more than four times faster than sequential file and more than 10 times faster than M-tree on the benchmark images set. The effect of the proposed AHI is also investigated by our implemented content based images retrieval system. © 2011 The Institute of Electrical Engineers of Japan.

关键词： Extraction

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Exploiting robustness in Petri net-based closed-loop systems to accommodate control specification changes

Exploiting robustness in Petri net-based closed-loop systems...

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2013 IEEE International Conference on Automation Science and Engineering, CASE 2013

作者： Li, Jun Zhou, Mengchu Dai, Xianzhong Key Laboratory of Measurement and Control of Complex Systems of Engineering China Ministry of Education Automation School of Southeast University Nanjing 210096 China Key Laboratory of Embedded System and Service Computing Ministry of Education Tongji University Shanghai 201804 China

ISBN: (纸本)9781479915156

Supervisory control reconfiguration has been paid more attention due to its capacity of handling the uncertainties including resource failures, capability degradation, and task changes in discrete event systems. However, the robustness of closed-loop systems in response to some specification changes was not addressed in the prior studies. This paper presents a reconfiguration method based on Petri nets and integer programming for supervisory control of resource allocation systems with changeable resource allocation relationships (control specifications). First, we propose a reconfiguration mechanism. It updates the P-invariant-based supervisor and evolves the state of the closed-loop system. The latter adapts to the certain changes in specifications by the self-regulation of the closed-loop system's state. It utilizes fully the robustness in a closed-loop system and avoids unnecessary modification of a supervisor. Then, a reconfiguration model with robustness analysis is proposed based on integer programming. By using it, a firing sequence of transitions as a serial of reconfiguration actions can be found. The execution of the sequence implements the state evolution of a closed-loop system. There is no need for making additional efforts to analyze state reachability of the system, since the firability condition of transitions is incorporated into the model. Finally, the method is illustrated through an example of a hospital emergency service system. © 2013 IEEE.

关键词： Closed loop systems

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Bayesian cognitive trust model based self-clustering algorithm for MANETs

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Science China(Information Sciences) 2010年第3期53卷 494-505页

作者： WANG Wei1,2,3 & ZENG GuoSun1,2,31Department of Computer Science & Technology, Tongji University, Shanghai 200092, China 2Tongji Branch, National Engineering & Technology Center of High Performance Computer, Shanghai 200092, China 3key Loboratory of embedded system and service computing, Ministry of Education, Shanghai 200092, China 1. Department of Computer Science & Technology Tongji University Shanghai 200092 China2. Tongji Branch National Engineering & Technology Center of High Performance Computer Shanghai 200092 China3. Key Loboratory of Embedded System and Service Computing Ministry of Education Shanghai 200092 China

With the introduction of mobile Ad hoc networks (MANETs), nodes are able to participate in a dynamic network which lacks an underlying infrastructure. Before two nodes agree to interact, they must trust that each will satisfy the security and privacy requirements of the other. In this paper, using the cognition inspired method from the brain informatics (BI), we present a novel approach to improving the search efficiency and scalability of MANETs by clustering nodes based on cognitive trust mechanism. The trust relationship is formed by evaluating the level of trust using Bayesian statistic analysis, and clusters can be formed and maintained autonomously by nodes with only partial knowledge. Simulation experiments show that each node can form and join proper clusters, which improve the interaction performance of the entire network. The essence of the underlying reason is analyzed through the theory of complex networks, revealing great scalability of this method.

关键词： trust model MANET self-clustering Bayesian method cognitive mobile

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Evolutionary behavior verification to the trustworthy banking software

Evolutionary behavior verification to the trustworthy bankin...

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International Conference on Computer Engineering and Technology

作者： Jiang, Zuo-Wen Tang, Xian-Fei Ding, Zhi-Jun Jiang, Chang-Jun Electronics and Information Engineering School Tongji University 201804 China Key Laboratory of Embedded System and Service Computing Ministry of Education Tongji University 200092 China College of Science and Technology NingBo University 315211 China

ISBN: (纸本)9781424463503

Oriented to the goal of high-quality banking softwares, trustworthiness is emerging to be important property. This paper studies how to apply formal methods into the trustworthy property preservation of evolutionary components, focusing on the safety property of the concurrent software behavior, this paper presents a new approach to curb the state explosion problem in the model checking based trustworthiness verification. By adopting the environment reduction paradigm, our method is able to reduce the global states of the system by hiding the internal actions of the environment that does not join in the interleaving composition. The method presented is proved and testified with a bank software case study. Experiment data shows that our method is able to improve the verification efficiency. © copy;2010 IEEE.

关键词： Model checking

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Verification of web service protocols by logic of knowledge

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Journal of Information and Computational Science 2011年第6期8卷 921-932页

作者： Chen, Qingliang Su, Kaile Cao, Ying Liu, Chanjuan School of Electronics Engineering and Computer Science Peking University Beijing 100871 China Department of Computer Science Jinan University Guangzhou 510632 China Key Laboratory of Embedded System and Service Computing Ministry of Education Tongji University Shanghai 200000 China Institute for Integrated and Intelligent Systems Griffith University Brisbane Australia

Web services is a popular distributed systems technology and its effectiveness and efficiency rely badly on the underlying protocols. And web service protocols are designed in XML formats so the message structures within are quite different from the conventional ones. Therefore, the well-established formal verification techniques for conventional protocols, which have gained substantial achievements in practice, cannot be applied directly to them because of the inherently different syntax. In this paper, we propose a justification-oriented and automatic formal approach to verify, in the standard Dolev-Yao model, concerned security properties expressed as epistemic notions, i. e., logic of knowledge, for web service protocols, based on a fault-preserving mapping tool called SuD (SOAP under Dolev-Yao). Our approach is significant because, instead of finding flaws in finite number of protocol sessions, the specifications we are to verify can hold in arbitrary number of sessions. © 2011 Binary Information Press.

关键词： Web services

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