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A dynamic context management scheme for 6LoWPAN

Journal of Computational Information Systems 2015年第9期11卷 3155-3163页

作者： Luo, Bingqing Sun, Zhixin Key Laboratory of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Nanjing China

This paper aims to propose a design of dynamic context management scheme for low-power wireless personal area networks based on IPv6 (6LoWPAN). In the scheme, a prefix auto-configuration mechanism is established to update the context table dynamically, therefore, no manual configuration or administration is further required. Meanwhile, based on the proposed 6LoWPAN structure, the context distribution and synchronization scheme can be achieved in extended 6LoWPAN domains, which maximized the benefit of 6LoWPAN header compression mechanism. Three main problems can be solved by the dynamic context management scheme on context sharing. One is how to update and maintain the context table;another is when to distribute the context information and the third one is how to synchronize the context information in extended 6LoWPAN domains. Judging from simulation perspective, this paper compares the compression ratio and energy consumed of dynamic context management scheme with that of static context table scheme. The results show that the performance of dynamic context management scheme works better for 6LoWPAN compression. ©, 2015, Binary Information Press. All right reserved.

关键词： wireless sensor networks

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Nonorthogonal object identification based on ghost imaging

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Photonics Research 2015年第5期3卷 238-242页

作者： Xiaofan Gu Shengmei Zhao Institute of Signal Processing & Transmission Nanjing University of Posts and Telecommunications (NUPT) Key Lab of Broadband Wireless Communication and Sensor Network Technology NUPT Ministry of Education

Ghost imaging could be used to make a quick identification of orthogonal objects by means of photocurrent correlation measurements. In this paper, we extend the method to identify nonorthogonal objects. In the method, an object is illuminated by one photon from an entangled pair, and the other one is diffracted into a particular direction by a pre-established multiple-exposure hologram in the idler arm. By the correlation measurements, the nonorthogonal object in the signal arm could be discriminated within a very short time. The constraints for the identification of nonorthogonal objects are presented, which show that the nonorthogonal objects can be discriminated when the overlapping portion between any two objects is less than half of all the objects in the set. The numerical simulations further verify the result.

关键词： Nonorthogonal object identification based on ghost imaging

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A hybrid recommendation algorithm based on social networks

A hybrid recommendation algorithm based on social networks

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International Conference on Quality of Service in Heterogeneous Wired/wireless networks (QSHINE)

作者： Jing Gong MeiLing Gao Bixiao Xu Wenjun Wang Zhixin Sun Key Laboratory of Broadband Wireless Communication and Sensor Network Technology Nanjing china College of mathematics & physics of Nanjing University of Posts and Telecommunications Key Laboratory of Broadband Wireless Communication and Sensor Network Technology Nanjing China

ISBN: (纸本)9781479982172

In the light of the problem of collaborative recommendation and content-based cold start, this paper proposes a hybrid recommendation system based on social network. The method is based on the user social relations network. According to the social behavior of user, by establishing the model of social network users, it puts forward the user similarity measure. Then it takes random walk algorithm as a basis and selects out N users who have the highest similarity with the users' interest. The test results show that this method can obtain better recommendation effect and customer satisfaction.

关键词： Collaboration Filtering algorithms Indexes Filtering

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The Dynamic Index Design of network Management Data on HBase

The Dynamic Index Design of Network Management Data on HBase

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2015 International Conference on Advanced Management Science and Information Engineering(AMSIE 2015)

作者： J.D.Yang C.S.Ren W.Mao D.Y.Zhang Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and TelecommunicationMinistry of Education

Aimed at the problems that data access delay and static index structure cannot meet the demand of frequent index update in the massive network management data,a dynamic index mechanism based on HBase and a special index table is designed in this *** key value of the table is comprised of key value and indexed column which come from original data,thus enforcing the map of the indexed column with the original *** address the problems in frequently adding and deleting data,an index update algorithm is established in which only changed data is *** results show that the index structure will be adjusted as the data is adding and deleting,rustling in the optimal search *** query efficiency based on the improved method raises 4.98 times in 100 thousand rows and 55.66 times in 1 million *** more the number of the rows increases,the more search efficiency obviously improves.

关键词： network management data HBase index

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New Evaluation Model on Web Site Credibility

New Evaluation Model on Web Site Credibility

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2015 International Conference on Computer Information Systems and Industrial Applications(CISIA2015)

作者： Y.Y.Ma F.Chen Z.X.Sun Key Lab of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Nanjing University of Posts and Telecommunications

ISBN: (纸本)9781510805750

In view of the existing web site credibility evaluation models failing to comprehensively consider the multiple attributes of trust,after learning the D- S evidence theory and fuzzy theory,a new web site credibility evaluation model is put forward in which the trust value is divided into historical trust value and the current trust *** study shows that the model can track the change of user preferences in real-time as well as can meet the dynamic nature of universal environment,so the trust assessment is more reasonable and accurate.

关键词： evaluation model d-s evidence theor fuzzy theory

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A RGB-D Face Recognition Approach without Confronting the Camera

A RGB-D Face Recognition Approach without Confronting the Ca...

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2015 IEEE International Conference on Computer and communications(ICCC 2015)

作者： Wei Zhou Jian-xin Chen Lei Wang Key Lab of Broadband Wireless Communication and Sensor Network Technology (Nanjing University of Posts and Telecommunications) Ministry of Education

Face recognition research mainly focuses on traditional 2D color images, which is extremely susceptible to be affected by external factors such as various viewpoints and has limited recognition accuracy. In order to achieve improved recognition performance, as well as the 3D face holds more abundant information than 2D, we present a 3D human face recognition algorithm using the Microsoft's Kinect. The proposed approach integrates the depth data with the RGB data to generate 3D face raw data and then extracts feature points, identifies the target via a two-level cascade classifier. Also, we build a 3D-face database including 16 individuals captured exclusively using Kinect. The experimental results indicate that the introduced algorithm can not only achieve better recognition accuracy in comparison to existing 2D and 3D face recognition algorithms when the probe face is exactly in front of Kinect sensor, but also can increase 9.3% of recognition accuracy compared to the PCA-3D algorithm when it is not confronting the camera.

关键词： 3D face recognition Kinect RGB-D images XML file classifier

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Performance analysis of two-hop-relay cellular systems with queueing capability

Performance analysis of two-hop-relay cellular systems with ...

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2015 International Conference on Information and communications Technologies, ICT 2015

作者： Lu, Weifeng Gu, Mengmeng Yang, Luxi College of Computer Nanjing University of Posts and Telecommunications Nanjing210023 China School of Information Science and Engineering SouthEast University Nanjing210096 China Jiangsu High Technology Research Key Laboratory for Wireless Sensor Networks Nanjing Jiangsu210023 China Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Jiangsu Province Nanjing Jiangsu210023 China

ISBN: (纸本)9781849199940

In this paper, we present a two-hop-relay WCDMA cellular system with queueing capability, where a call can wait in the incoming buffer at the congested Base Transceiver Station (BTS) if no channel is immediately available, so as to reduce the call blocking rate. We develop an analytic model based on Multidimensional Markov chains. Then based on this model, we can obtain the average transmission rate and the queuing delay performance of the system respectively. Finally, through numerical calculation, we analyze the impact of the various parameters on the performance of the two-hop-relay WCDMA cellular system with queueing capability.

关键词： Queueing theory

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Energy efficient subchannel pairing for buffer-aided multi-relay MIMO-OFDM networks

Energy efficient subchannel pairing for buffer-aided multi-r...

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International Conference on wireless communications and Signal Processing (WCSP)

作者： Shuang Yang Yueming Cai Junquan Hu Wendong Yang Lei Wang Weiwei Yang College of Communications Engineering PLA University of Science and Technology Nanjing China Key Lab of Broadband Wireless Communication and Sensor Network Technology Ministry of Education

ISBN: (纸本)9781467376884

In this paper, we consider the buffer-aided multi-relay MIMO-OFDM networks and propose a joint space-time-frequency subchannel pairing scheme, in which subchannels of the source to relay links and relay to the destination links are paired in time, frequency, and space domain (TPFPSP) simultaneously. TPFPSP scheme can increase the equivalent channel gains between source and destination. We derive new expressions for the energy efficiency, the system capacity and the outage probability to examine the performance of TPFPSP scheme. Our analytical and numerical results outline that this TPFPSP scheme brings higher capacity, energy efficiency and better outage probability performance to our system. This work reported here provides detailed insights into the design of new subchannel pairing scheme, which achieves full diversity in space, time and frequency domains.

关键词： Relays MIMO Fading OFDM Eigenvalues and eigenfunctions Energy efficiency wireless communication

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Social-aware file-sharing mechanism for device-to-device communications

Social-aware file-sharing mechanism for device-to-device com...

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International Conference on wireless communications and Signal Processing (WCSP)

作者： Lei Wang Lulu Gao Aiqing Zhang Mingkai Chen National Mobile Communications Research Laboratory Southeast University Nanjing China NUPT Key Lab of Broadband Wireless Communication and Sensor Network Technology China

ISBN: (纸本)9781467376884

Device-to-device (D2D) communication technology can significantly improve energy efficiency and offload base station traffic. It has become a new research focus in next generation mobile communications. In this paper, a file-sharing mechanism based on social networks is proposed for the D2D communication system underlaying cellular networks aiming at improving the users' quality of experience (QoE). In the proposed mechanism, all users are divided into several groups according to the documentation requirements. Then the D2D communication links are built within each group by fully considering the social relationships and trust degrees of users. The target files give priority to be shared through the D2D mode. Theoretical analysis and extensive simulation results show clearly that the social relationships can affect the whole wireless networks significantly. Selecting a user with the largest social degree as a central user can greatly reduce the transmission delay, relieve the heavy burden of base stations and then optimize the overall performance of cellular communication systems.

关键词： Base stations Social network services Delays wireless communication Mobile communication Quality of service

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Inclination gradient-based fall detection algorithm for wrist-worn device

Inclination gradient-based fall detection algorithm for wris...

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IEEE International Conference on Consumer Electronics-Taiwan (ICCE-TW)

作者： ShengQian Zhou Jianxin Chen Xinzhi Wang Liang Zhou Baoyu Zhen Jingwu Cui Key Lab of Broadband Wireless Communication and Sensor Network Technology of Ministry of Education Nanjing University of Posts & Telecommunications Nanjing University of Posts and Telecommunications Nanjing CN

ISBN: (纸本)9781479987467

Fall detection is one of the feasible solutions for solving the problem of aging of population. This paper presents an algorithm to detect falling for the elderly with one wrist-worn device. The algorithm has lower computation complexity to determine the fall event according to the inclination gradient. Experimental results show that it performs better than another similar devices with the average sensitivity and specificity of 94.44% and 100%, respectively.

关键词： Accelerometers Senior citizens Sensitivity Performance evaluation Classification algorithms Complexity theory Legged locomotion

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