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Scheme for realizing passive quantum key distribution with heralded single-photon sources

Physical Review A 2016年第3期93卷 032312-032312页

作者： Qin Wang Chun-Hui Zhang Xiang-Bin Wang Institute of Signal Processing and Transmission Nanjing University of Posts and Telecommunications Nanjing 210003 China Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Nanjing 210003 China Key Laboratory of Quantum Information University of Science and Technology of China Hefei 230026 China Department of Physics and State Key Laboratory of Low Dimensional Quantum Physics Tsinghua University Beijing 100084 China Jinan Institute of Quantum Technology Shandong Academy of Information Technology Jinan China

We present a scheme for realizing passive quantum key distribution with heralded single-photon sources. In this scheme, the idler light from the parametric down-conversion process is split into two parts and sent into two local detectors individually. Then all the clicking and nonclicking events are used to herald the arrival and nonarrival of the signal light. As a result, a precise estimation of the behavior of the single-photon pulses can be achieved without changing the light intensity. Furthermore, we compare our scheme with other existing methods with the Bennett-Brassard 1984 (BB84) protocol through numerical simulations. Our simulations demonstrate that the performance of our scheme can greatly overcome other existing practical methods and approach very close to the asymptotic case of using infinite-decoy-state methods.

关键词： Quantum cryptography

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T-QoS-aware based parallel ant colony algorithm for services composition

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Journal of Systems Science & Complexity 2015年第5期28卷 1100-1106页

作者： Lin Zhang Kaili Rao Ruchuan Wang College of Computer Nanjing University of Posts and Telecommunications Institute of Computer Technology Nanjing University of Posts and Telecommunications Jiangsu High Technology Research Key Laboratory for Wireless Sensor Networks Key Lab of Broadband Wireless Communication and Sensor Network Technology Nangjing University of Posts and Telecommunications

In order to make cloud users get credible, high-quality composition of services, the trust quality of service aware(TQoS-aware) based parallel ant colony algorithm is proposed. Our approach takes the service credibility as the weight of the quality of service, then calculates the trust service quality T-QoS for each service, making the service composition situated in a credible environment. Through the establishment on a per-service T-QoS initialization pheromone matrix, we can reduce the colony's initial search time. By modifying the pheromone updating rules and introducing two ant colonies to search from different angles in parallel,we can avoid falling into the local optimal solution, and quickly find the optimal combination of global solutions. Experiments show that our approach can combine high-quality services and the improvement of the operational success rate. Also, the convergence rate and the accuracy of optimal combination are improved.

关键词： services composition trust service quality ant colonyalgorithm parallel

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Fair Downlink Traffic Management for Hybrid LAA-LTE/Wi-Fi networks

Fair Downlink Traffic Management for Hybrid LAA-LTE/Wi-Fi Ne...

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IEEE Global communications Conference

作者： Yang Li Mengying Zhang Yang Yang Xudong Wang School of Information Science and Technology ShanghaiTech University Key Lab of Wireless Sensor Network and Communication Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences UM-SJTU Joint Institute Shanghai Jiao Tong University

ISBN: (纸本)9781509013296

Due to the scarcity of the licensed spectrum, Licensed-Assisted Access Long-Term Evolution (LAA-LTE) network can be deployed in unlicensed spectrum, which is currently occupied by different Wi-Fi systems. It is a very challenging problem to ensure fair coexistence between LAA-LTE and Wi-Fi networks, in terms of spectrum sharing and traffic management. To solve this problem, a Fair Downlink Traffic Management (FDTM) scheme is proposed in this paper for hybrid LAA-LTE/Wi-Fi networks. By using the genetic algorithm, FDTM tunes the minimum Contention Window (CW_(min)) values and assigns feasible weights for the LAA eNBs with different traffic loads, thus to achieve (1) fair spectrum sharing with the existing Wi-Fi networks in unlicensed bands, and (2) fair service differentiation for downlink LAA-LTE traffic. Numerical results show our FDTM scheme can guarantee the throughput of Wi-Fi networks in shared unlicensed spectrum, while supporting proportional fairness for the LAA eNBs with different weights and CW_(min) values.

关键词： IEEE 802.11 Standard Throughput Downlink Genetic algorithms Long Term Evolution Biological cells Electronic mail

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Deterministic realization of collective measurements via photonic quantum walks

arXiv

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arXiv 2017年

作者： Hou, Zhibo Tang, Jun-Feng Shang, Jiangwei Zhu, Huangjun Li, Jian Yuan, Yuan Wu, Kang-Da Xiang, Guo-Yong Li, Chuan-Feng Guo, Guang-Can Key Laboratory of Quantum Information University of Science and Technology of China CAS Hefei230026 China Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of China Hefei230026 China Naturwissenschaftlich-Technische Fakultät Universität Siegen Siegen57068 Germany Beijing Key Laboratory of Nanophotonics Ultrafine Optoelectronic Systems School of Physics Beijing Institute of Technology Beijing100081 China Institute for Theoretical Physics University of Cologne Cologne50937 Germany Department of Physics Center for Field Theory and Particle Physics Fudan University Shanghai200433 China Institute for Nanoelectronic Devices and Quantum Computing Fudan University Shanghai200433 China State Key Laboratory of Surface Physics Fudan University Shanghai200433 China Collaborative Innovation Center of Advanced Microstructures Nanjing210093 China Institute of Signal Processing Transmission Nanjing University of Posts and Telecommunications Nanjing210003 China Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Nanjing210003 China

Collective measurements on identically prepared quantum systems can extract more information than local measurements, thereby enhancing information-processing efficiency. Although this nonclassical phenomenon has been known for two decades, it has remained a challenging task to demonstrate the advantage of collective measurements in experiments. Here we introduce a general recipe for performing deterministic collective measurements on two identically prepared qubits based on quantum walks. Using photonic quantum walks, we realize experimentally an optimized collective measurement with fidelity 0.9946 without post selection. As an application, we achieve the highest tomographic efficiency in qubit state tomography to date. Our work offers an effective recipe for beating the precision limit of local measurements in quantum state tomography and metrology. In addition, our study opens an avenue for harvesting the power of collective measurements in quantum information processing and for exploring the intriguing physics behind this power. Copyright © 2017, The Authors. All rights reserved.

关键词： Quantum optics

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A Context-aware Data Processing Model in power communication networks

A Context-aware Data Processing Model in power communication...

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2015 IEEE/CIC International Conference on communications in China - Workshops, CIC/ICCC 2015

作者： Guo, Yunfei Wang, Kun Liu, Shidong Guo, Jinghong Lu, Heng Smart Grid Research Institute State Grid Nanjing210003 China Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Nanjing210003 China

ISBN: (纸本)9781467397018

The power communication networks is a relatively complex system with high security, which is performed in a number of ways, such as safety of power generation equipment, security of transmission and distribution lines, as well as data transmission security. The core of power communication networks security is context-aware data processing. With continuously extending in scale of the power communication networks, power communication data process become more complicated. In order to realize automatization of data processing of the power communication networks, this paper proposed a Context-aware Data Processing Model in power communication networks (CDPM). In this three-layer architecture, a Distributed Database Based on Data Categorization (DDB-DC) is designed in storage layer, which is able to choose the most efficient approach to store the context-aware data from the gathering layer according to different context-aware data types. Then, a Real-time Feature Extraction algorithm (RFE) for context-aware systems is presented in the computing layer to process the context-aware data stream. The model is a new data processing method in power communication networks. © 2015 IEEE.

关键词： Feature extraction

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Feedback free distributed video coding rate control algorithm

Feedback free distributed video coding rate control algorith...

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International Conference on Information technology and Computer Application Engineering, ITCAE 2014

作者： Zhang, Deng Yin Ma, Teng Sci-tech Park of Internet of Things Nanjing University of Posts and Telecommunication Nanjing China Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunication Ministry of Education Nanjing China

ISBN: (纸本)9781138027176

In this paper, based on the feedback free distributed video coding system, a rate control algorithm was proposed for Wyner-Ziv frames. First, calculate the maximum correlation of coefficient band level between the source WZ frames and adjacent key frames in DCT domain, and the quantization matrix was determined based on maximum correlation and the QP of the key-frames;then, according to the generated low-complexity side information and source WZ frame with DCT transformation and quantization, allocate the bit plane rate. Experimental results show, compared with the existing rate control algorithm without feedback channel, the proposed algorithm can effectively improve the Rate-Distortion performance of the feedback free system with little additional complexity. © 2015 Taylor & Francis Group, London.

关键词： Feedback

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An all dynamic MAC protocol for wireless Body Area network

An all dynamic MAC protocol for Wireless Body Area Network

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11th International Conference on wireless communications, networking and Mobile Computing (WiCOM 2015)

作者： Jun Wang Yutian Xie Qiong Yi Key Lab of Broadband Wireless Communication and Sensor Network Technology NJUPT Nanjing Jiangsu China

ISBN: (纸本)9781510821279

wireless Body Area network (WBAN) is considered as a special type of WSN. It consists of low-power wireless sensor nodes, which are placed on or implanted in the body for continuous health monitoring. MAC protocol is responsible for conflict detection, processing, priority control, timeslot assignment, transmission order etc. So the design of MAC protocol plays an important role in the reliability and efficiency of WBAN. In order to increase the energy efficiency and reliability of WBAN, a new wireless body area network MAC protocol-AD-MAC protocol is proposed. The proposed protocol adopts dynamic priority control, dynamic timeslot allocation mechanism and dynamic length allocation mechanism of different access periods to achieve reliable transmission in the situation of low latency and low power consumption. The simulation results show that AD-MAC protocol is superior to IEEE802.15.6 MAC and CA-MAC in terms of throughput, power consumption and delay.

关键词： Energy-Efficiency IEEE802.15.6 wireless Body Area network body area networks MAC protocol Methotrexate-Actinomycin-Chlorambucil Regimen Energy efficiency wireless dynamic priority conflict detection

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An improved static B+ tree index adaptive to cloud environment for analytic application 5th

An improved static B+ tree index adaptive to cloud environme...

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5th International Conference on Environmental Science and Information Application technology, ESIAT 2014

作者： Wan, Mingxiang Ren, Chunshao Zhang, Dengyin Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunication Ministry of Education Nanjing China Sci-tech Park of Internet of Things Nanjing University of Posts and Telecommunication Nanjing210003 China

ISBN: (纸本)9781138028142

B+ Tree is a special balanced multiway tree with flexible structure and node pages linking to each other. It supports not only rapid random query, but also range query. But B+ Tree index cannot be directly migrated since data storage architecture is different in cloud environment. Based on the characteristics of cloud computing master-slave architecture and combined with the characteristics of the columnar storage in the cloud environment, this paper proposes an improved secondary index of B+ Tree. In this index, primary key still uses key-Value style hash index, which can not only get high search efficiency, but also maintain load balance;other property columns will apply improved B+ Tree index, which can solve the problem of high time complexity when querying non-primary key and also support range query of non-primary key property. © 2015 Taylor & Francis Group, London.

关键词： Flexible structures

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Distributed cooperative spectrum sensing based on consensus among reliable secondary users

Distributed cooperative spectrum sensing based on consensus ...

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International Conference on wireless communications and Signal Processing, WCSP 2015

作者： Wei, Ji Haixi, Cao Zhen, Yang College of Telecommunication and Information Engineering Nanjing University of Posts and Telecommunications Nanjing210003 China Key Lab of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Nanjing University of Posts and Telecommunications Nanjing210003 China

ISBN: (纸本)9781467376860

Cooperative spectrum sensing (CSS) is a key technology to improve the sensing performance. Fully distributed CSS has been applied in cognitive radio ad hoc networks with good detection performance. However, when the number of secondary users (SUs) is large and the range of cognitive radio network is wide, sensing overheads (e.g., time and energy consumption) will increase correspondingly. Meanwhile, the reliability of SUs will potentially influence the detection performance. In this paper, a fully decentralized cooperative spectrum sensing scheme based on consensus theory among reliable SUs is proposed. Firstly, belief vector is used for distinguishing the reliable SUs from the unreliables. Secondly, the sub network with most reliable SUs is chose as reliable region, in which sensing information of reliable SUs can be exchanged among their one-hop neighbors with finite iterations based on consensus theory. Lastly, SUs in consensus network will get a consensus sensing outcome which will be shared with SUs outside of consensus network. The proposed scheme does not need the prior knowledge of primary user in the entire process. Simulation results show that the proposed scheme has better detection performance than traditional methods. © 2015 IEEE.

关键词： Energy utilization

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A dynamic context management scheme for 6LoWPAN

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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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