检索结果-内蒙古大学图书馆

An improved apriori algorithm with prejudging and screening

学校读者我要写书评

暂无评论

An improved apriori algorithm with prejudging and screening

International Conference on Computer, communication and Computational Sciences, ICCCCS 2016

作者： Zhao, Xuejian Li, Dongjun Yuan, Yuan Sun, Zhixin Chen, Yong Key Lab of Broadband Wireless Communication and Sensor Network Technology of Ministry of Education Nanjing University of Posts and Telecommunications Nanjing China Jiangsu Posts & Telecommunications Planning and Designing Institute Co. LTD Nanjing China Nanjing Longyuan Microelectronic Co. LTD Nanjing China

ISBN: (纸本)9789811037696

Association rule analysis, as one of the significant means of data mining, plays an important role in discovering the implicit knowledge in massive transaction data. Aiming at the inherent defects of the classic Apriori algorithm, this paper proposes IAPS (Improved Apriori with Prejudging and Screening) algorithm. IAPS algorithm adds a prejudging and screening procedure on the basis of the self-join and pruning progress in Apriori algorithm which can reduce and optimize the k-frequent item sets using prior probability. IAPS algorithm simplifies the operation process of mining frequent item sets. Experimental results show that the improved algorithm can effectively reduce the number of scanning databases and reduce the running time of the algorithm. © Springer Nature Singapore Pte Ltd. 2017.

关键词： Association rules

Users' Media Cloud Assisted D2D communications for Distributed Caching Underlaying Cellular network

学校读者我要写书评

暂无评论

China communications 2016年第8期13卷 13-23页

作者： Mingkai Chen Lei Wang Jianxin Chen Key Lab of Broadband Wireless Communication and Sensor Network Technology (Nanjing University of Posts and Telecommunications) Ministry of Education The State Key Laboratory of Integrated Services Networks Xidian University

In cellular networks, the proximity devices may share files directly without going through the e NBs, which is called Device-to-Device communications(D2D). It has been considered as a potential technological component for the next generation of communication. In this paper, we investigate a novel framework to distribute video files from some other proximity devices through users' media cloud assisted D2 D communication. The main contributions of this work lie in: 1) Providing an efficient algorithm Media Cloud Cluster Selecting Scheme(MCCSS) to achieve the reasonable cluster; 2) Distributing the optimum updating files to the cluster heads, in order to minimize the expected D2 D communication transmission hop for files; 3) Proposing a minimum the hop method, which can ensure the user obtain required file as soon as possible. Extensive simulation results have demonstrated the efficiency of the proposed scheme.

关键词： device-to-device communication users’ media cloud cache content delivery

Collusion detector based on G-N algorithm for trust model

学校读者我要写书评

暂无评论

Journal of Systems Engineering and Electronics 2016年第4期27卷 926-935页

作者： Lin Zhang Na Yin Jingwen Liu Ruchuan Wang College of Computer Nanjing University of Posts and TelecommunicationsNanjing 210003China Jiangsu High Technology Research Key Laboratory for Wireless Sensor Networks Nanjing 210003China Key Lab of Broadband Wireless Communication and Sensor Network Technology Nangjing University of Posts and TelecommunicationsNangjing 210003China

In the open network environment, malicious attacks to the trust model have become increasingly serious. Compared with single node attacks, collusion attacks do more harm to the trust model. To solve this problem, a collusion detector based on the GN algorithm for the trust evaluation model is proposed in the open Internet environment. By analyzing the behavioral characteristics of collusion groups, the concept of flatting is defined and the G-N community mining algorithm is used to divide suspicious communities. On this basis, a collusion community detector method is proposed based on the breaking strength of suspicious communities. Simulation results show that the model has high recognition accuracy in identifying collusion nodes, so as to effectively defend against malicious attacks of collusion nodes.

关键词： trust model collusion detector G-N algorithm

3D shape segmentation via shape fully convolutional networks

学校读者我要写书评

暂无评论

arXiv 2017年

作者： Wang, Pengyu Gan, Yuan Shui, Panpan Yu, Fenggen Zhang, Yan Chen, Songle Sun, Zhengxing State Key Lab for Novel Software Technology Nanjing University Key Lab of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Nanjing University of Posts and Telecommunications

We design a novel fully convolutional network architecture for shapes, denoted by Shape Fully Convolutional networks (SFCN). 3D shapes are represented as graph structures in the SFCN architecture, based on novel graph convolution and pooling operations, which are similar to convolution and pooling operations used on images. Meanwhile, to build our SFCN architecture in the original image segmentation fully convolutional network (FCN) architecture, we also design and implement a generating operation with bridging function. This ensures that the convolution and pooling operation we have designed can be successfully applied in the original FCN architecture. In this paper, we also present a new shape segmentation approach based on SFCN. Furthermore, we allow more general and challenging input, such as mixed datasets of different categories of shapes which can prove the ability of our generalisation. In our approach, SFCNs are trained triangles-to-triangles by using three low-level geometric features as input. Finally, the feature voting-based multi-label graph cuts is adopted to optimise the segmentation results obtained by SFCN prediction. The experiment results show that our method can effectively learn and predict mixed shape datasets of either similar or different characteristics, and achieve excellent segmentation results. . Copyright © 2017, The Authors. All rights reserved.

关键词： network architecture

MPLB: A Load Balance Scheme of Joint Resource Scheduling in Heterogeneous wireless network

学校读者我要写书评

暂无评论

MPLB: A Load Balance Scheme of Joint Resource Scheduling in ...

International Conference on Cyber-Enabled Distributed Computing and Knowledge Discovery, CyberC

作者： Xiaoyong Lin Pengwei Yin Yun Xia Yang Yu Tingting Qiu Xiaoming Wang Lixiang Li Key Lab of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Nanjing China College of Communication & Information Engineering Nanjing University of Posts and Telecommunications Nanjing China

A user terminal with multi-mode wireless interface is always located its position in the covered area of heterogeneous wireless network (HWN), there are too many algorithms about vertical handover (VHO) of multiple attributes decision making (MADM) network selections about HWN. According the analysis of current applications of wireless service, regular service has been classified into four kinds, including voice, video, small data and big data, and the proportions of wireless video and big data service may acquire an unavailable bandwidth for each individual wireless station, which will lead to a heavy load and a lower satisfaction rate. A multiple properties load balance (MPLB) scheme is proposed to solve this joint resource scheduling(JRS) problem properly, MPLB scheme first gave an enhanced architecture including the JSR sub-layer, then model of MPLB is established from the candidate wireless network, five aggregated network performance properties have been defined mathematically, the candidate of best grey relational coefficients (GRC) of grey relational analysis(GRA) algorithm is optimally selected as the final executable scheme, after the description of a general flowchart of MPLB scheme. The simulation results proved the MPLB scheme has a more stable load balance effects than those of VHO, so did most users of MPLB gain higher satisfaction rate, slightly different with the four kinds of service. It can be concluded theoretically that the MPLB scheduling scheme could achieve both the load balance on the service providers side and the increased quality of experience of satisfaction rate on the wireless user side, which would bring out some new thoughts in the future user centric network.

关键词： Distributed computing Knowledge discovery

Practical decoy-state reference-frame-independent measurement-device-independent quantum key distribution

学校读者我要写书评

暂无评论

Physical Review A 2017年第3期95卷 032309-032309页

作者： Chun-Mei Zhang Jian-Rong Zhu Qin Wang Institute of Signal Processing Transmission Nanjing University of Posts and Telecommunications Nanjing 210003 China and Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Nanjing 210003 China

Reference-frame-independent measurement-device-independent quantum key distribution (RFI-MDI-QKD) is proposed to remove all possible detector side channel attacks without the alignment of reference frames. Due to unavoidable multiphoton events in practical sources, the decoy-state method is always adopted in real-life QKD systems. Unlike original MDI-QKD (O-MDI-QKD), the characterization on practical decoy-state RFI-MDI-QKD is still absent to date. In this paper, we investigate the performance of practical decoy-state RFI-MDI-QKD at different misalignments of reference frames with full parameter optimization when considering statistical fluctuations, and provide a clear comparison between decoy-state RFI-MDI-QKD and O-MDI-QKD. Simulation results demonstrate that decoy-state RFI-MDI-QKD can exhibit performance comparable to that of O-MDI-QKD in practical scenarios, which is very robust in QKD systems.

关键词： Quantum communication Quantum cryptography

Thermal effects of the quantum states generated from the isomorphs of PPKTP crystal

学校读者我要写书评

暂无评论

arXiv 2018年

作者： Jin, Rui-Bo Chen, Guo-Qun Laudenbach, Fabian Zhao, Shengmei Lu, Pei-Xiang Laboratory of Optical Information Technology Wuhan Institute of Technology Wuhan430205 China Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Security & Communication Technologies Center for Digital Safety & Security AIT Austrian Institute of Technology GmbH Donau-City-Str. 1 Vienna1220 Austria Quantum Optics Quantum Nanophysics and Quantum Information Faculty of Physics University of Vienna Boltzmanngasse 5 Vienna1090 Austria

We theoretically and numerically investigate the temperature-dependent properties of the biphotons generated from four isomorphs of periodically poled KTiOPO4 (PPKTP): i.e., PPRTP, PPKTA, PPRTA and PPCTA. It is discovered that the first type of group-velocity-matched (GVM) wavelength is decreased by 6.4, 1.2, 8.9, 25.6 and 6.3 nm, while the phase-matched wavelength is decreased by 4.4, -0.4, -1.2, 29.1 and 59.5 nm for PPKTP, PPRTP, PPKTA, PPRTA and PPCTA, respectively, when the temperature is increased from 20 ◦C to 120 ◦C. Although the maximal spectral purity of the heralded single photons is not changed at different temperature, the Hong-Ou-Mandel (HOM) interference shows different patterns due to a shift of the joint spectral amplitude. These thermal effects are very important for precise control of the quantum state for the future applications in quantum information processing, for example, in quantum interference or spectroscopy. Copyright © 2018, The Authors. All rights reserved.

关键词： Quantum optics

Physical-layer security for indoor visible light communications: Secrecy capacity analysis

学校读者我要写书评

暂无评论

arXiv 2018年

作者： Wang, Jin-Yuan Liu, Cheng Wang, Jun-Bo Wu, Yongpeng Lin, Min Cheng, Julian Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Nanjing210003 China National Mobile Communications Research Laboratory Southeast University Nanjing210096 China Department of Electronic Engineering Shanghai Jiao Tong University Minhang200240 China School of Engineering University of British Columbia KelownaBCV1V 1V7 Canada

This paper investigates the physical-layer security for an indoor visible light communication (VLC) network consisting of a transmitter, a legitimate receiver and an eavesdropper. Both the main channel and the wiretapping channel have nonnegative inputs, which are corrupted by additive white Gaussian noises. Considering the illumination requirement and the physical characteristics of lighting source, the input is also constrained in both its average and peak optical intensities. Two scenarios are investigated: One is only with an average optical intensity constraint, and the other is with both average and peak optical intensity constraints. Based on information theory, closed-form expressions of the upper and lower bounds on secrecy capacity for the two scenarios are derived. Numerical results show that the upper and lower bounds on secrecy capacity are tight, which validates the derived closed-form expressions. Moreover, the asymptotic behaviors in the high signal-to-noise ratio (SNR) regime are analyzed from the theoretical aspects. At high SNR, when only considering the average optical intensity constraint, a small performance gap exists between the asymptotic upper and lower bounds on secrecy capacity. When considering both average and peak optical intensity constraints, the asymptotic upper and lower bounds on secrecy capacity coincide with each other. These conclusions are also confirmed by numerical results. Copyright © 2018, The Authors. All rights reserved.

关键词： Gaussian noise (electronic)

Bandit inspired beam searching scheme for mmWave high-speed train communications

学校读者我要写书评

暂无评论

arXiv 2018年

作者： Wang, Jun-Bo Cheng, Ming Wang, Jin-Yuan Lin, Min Wu, Yongpeng Zhu, Huiling Wang, Jiangzhou National Mobile Communications Research Laboratory Southeast University Nanjing210096 China Key Lab of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Nanjing University of Posts and Telecommunications Nanjing210003 China Shanghai Key Laboratory of Navigation and Location Based Services Shanghai Jiao Tong University Minhang200240 China School of Engineering and Digital Arts University of Kent Canterbury KentCT2 7NT United Kingdom

High-speed trains (HSTs) are being widely deployed around the world. To meet the high-rate data transmission requirements on HSTs, millimeter wave (mmWave) HST communications have drawn increasingly attentions. To realize sufficient link margin, mmWave HST systems employ directional beamforming with large antenna arrays, which results in that the channel estimation is rather time-consuming. In HST scenarios, channel conditions vary quickly and channel estimations should be performed frequently. Since the period of each transmission time interval (TTI) is too short to allocate enough time for accurate channel estimation, the key challenge is how to design an efficient beam searching scheme to leave more time for data transmission. Motivated by the successful applications of machine learning, this paper tries to exploit the similarities between current and historical wireless propagation environments. Using the knowledge of reinforcement learning, the beam searching problem of mmWave HST communications is formulated as a multi-armed bandit (MAB) problem and a bandit inspired beam searching scheme is proposed to reduce the number of measurements as many as possible. Unlike the popular deep learning methods, the proposed scheme does not need to collect and store a massive amount of training data in advance, which can save a huge amount of resources such as storage space, computing time, and power energy. Moreover, the performance of the proposed scheme is analyzed in terms of regret. The regret analysis indicates that the proposed schemes can approach the theoretical limit very quickly, which is further verified by simulation results. Copyright © 2018, The Authors. All rights reserved.

关键词： Millimeter waves