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Quantum Secret broadcast for Wireless Quantum Networks

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International Journal of Communications, Network and System Sciences 2017年第8期10卷 7-18页

作者： Tao Shang Gang Du Jianwei Liu School of Electronic and Information Engineering Beihang University Beijing China

In wireless quantum networks, nodes communicate by means of pre-distribution for entangled pairs and relay path establishment for quantum teleportation. However, simple point-to-point communication seriously restricts the efficiency of quantum communication. Inspired by sharing idea of quantum secret sharing (QSS), which is based on three collaborative nodes with pre-shared GHZ (Greenberger-Horne-Zeilinger) states, we propose a quantum secret broadcast scheme to improve network performance. In a cluster net-work cored on three parties of QSS, three cluster heads with pre-shared GHZ states are senders, while cluster members are receivers. One cluster head encodes secret messages on auxiliary particles by performing certain operations on them with GHZ particles, then three cluster heads measure their own par-ticles and broadcast measurement results honestly. Based on the specific correlation of measurement results and secret messages, all receivers can re-cover the secret messages. Furthermore, to prevent eavesdropping, cluster heads can update an encoding key periodically. Analysis shows the proposed scheme is more efficient than previous schemes in wireless quantum net-works, especially when the number of receivers is larger. Besides, in the proposed scheme, attacks on quantum channel based on GHZ state can be detected, and eavesdroppers cannot recover messages correctly for lack of suitable decoding key.

关键词： Quantum Secret Sharing Quantum Secret broadcast Cluster Network

An Efficient Identity-Based Homomorphic broadcast Encryption

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Journal of Computer and Communications 2019年第2期7卷 23-30页

作者： Mei Cai IT Department Jinan University Library Guangzhou China

broadcast encryption (BE) allows a sender to broadcast its message to a set of receivers in a single ciphertext. However, in broadcast encryption scheme, ciphertext length is always related to the size of the receiver set. Thus, how to improve the communication of broadcast encryption is a big issue. In this paper, we proposed an identity-based homomorphic broadcast encryption scheme which supports an external entity to directly calculate ciphertexts and get a new ciphertext which is the corresponding result of the operation on plaintexts without decrypting them. The correctness and security proofs of our scheme were formally proved. Finally, we implemented our scheme in a simulation environment and the experiment results showed that our scheme is efficient for practical applications.

关键词： Identity-Based broadcast Encryption Homomorphic Communication

Achievable Rate Regions for Orthogonally Multiplexed MIMO broadcast Channels with Multi-Dimensional Modulation

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International Journal of Communications, Network and System Sciences 2010年第1期3卷 1-18页

作者： Marthe KASSOUF Harry LEIB 不详

In this work, we consider a multi-antenna channel with orthogonally multiplexed non-cooperative users, and present its achievable information rate regions with and without channel knowledge at the transmitter. With an informed transmitter, we maximize the rate for each user. With an uninformed transmitter, we consider the optimal power allocation that causes the fastest convergence to zero of the fraction of channels whose mutual information is less than any given rate as the transmitter channel knowledge converges to zero. We assume a deterministic space and time dispersive multipath channel with multiple transmit and receive antennas, generating an orthogonally multiplexed Multiple-Input Multiple-Output (MIMO) broadcast system. Under limited transmit power;we consider different user specific space-time modulation formats that represent assignments of signal dimensions to transmit antennas. For the two-user orthogonally multiplexed MIMO broadcast channels, the achievable rate regions, with and without transmitter channel knowledge, evolve from a triangular region at low SNR to a rectangular region at high SNR. We also investigate the maximum sum rate for these regions and derive the associated power allocations at low and high SNR. Furthermore, we present numerical results for a two-user system that illustrate the effects of channel knowledge at the transmitter, the multi-dimensional space-time modulation format and features of the multipath channel.

关键词： MIMO Channels broadcast Systems Capacity Region Space-Time Coding

P2P Model Based on Isolated broadcast Domains

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Advances in Internet of Things 2012年第3期2卷 74-77页

作者： Jianchun Li Gongbing Guo Jianyong Li Daoying Huang Coll. of Computer & Communication Eng. Zhengzhou University of Light Industry Zhengzhou Henan China

Resource location is the most important issue for Peer-to-Peer (P2P) system and flooding is the fundamental mechanism for unstructured P2P systems. Redundant messages will exponential growth with flooding scope increasing which severely influences the scalability of the system. In this paper, a new P2P model based on isolated broadcast domains is given to reduce the amount of redundant messages by limiting the radius of messages transmitted. Analysis and experiments show that this model can guarantee coverage of nodes and significantly reduce the amount of redundant messages generated.

关键词： P2P Model Isolated broadcast Domains Redundant Messages

使用broadcast Disks方法分布的空中位图索引

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计算机工程 2006年第2期32卷 53-55页

作者：洪圆孙未未施伯乐复旦大学计算机与信息技术系上海200433

提出一种使用broadcastDisks算法来分布位图索引的空中索引方法,根据数据项访问概率,使用位图作为数据广播的索引,减少了移动终端等待数据时保持激活状态的时间,达到节能的目的。

关键词： broadcast Disks 位图索引数据广播访问概率节能

How to Listen to a Foreign broadcast

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语言教育 1992年第1期 34-36页

作者：萧坤

Listening to a radio broadcast in a foreign language is difficult for many of us. We may have studied thelanguage for several years, and are able to read it, per-haps even write in it. But listening and understandingthe spoken language requires special skill. Some peoplehave a natural ability that helps them to learn languagequickly. Others must study for a long time. Everyone,

关键词： listening spoken skill write broadcast beginning speaking remember getting items

Real-time and fast retrieve the coseismic wave by GPS, strong-motion combined measurements and broadcast ephemeris

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Real-time and fast retrieve the coseismic wave by GPS, stron...

On Neologism in broadcast News Reporting

第五届中国卫星导航学术年会

作者： Rui Tu The Germany Research Center for Geosciences

In this study, we propose an approach of real-time and fast retrieving the coseismic waves by GPS, strong-motion combined measurements and broadcast ephemeris. Firstly, the velocity observation equations and state equations of the strong-motion measurements are introduced into Precise Point Positioning （PPP） solution model, the baseline shifts of the strong-motion are real-time estimated as unknown parameters like other positioning parameters by a Kalman filter. Then, the true velocity wave was retrieved by correcting the estimated baseline shifts, the true displacement wave was recovered by the velocity integrated displacement after de-trending a linear correction. The series of validation results have shown that, this method can fast and accurate retrieve the coseismic wave, the convergence time is smaller than one minute, and the precision are better than 2 mm/s and 2.5 cm for velocity and displacement respectively.

关键词： GPS and Strong-motion combined measurements broadcast ephemeris Coseismic wave retrieving Real-time

来源： cnki会议评论

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cnki会议

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海外英语 2014年第16期 232-232,246页

作者：吕慧青岛理工大学琴岛学院山东青岛266000

Based on the neologism in the broadcast news reporting, this paper will introduce different kinds of the most frequently used words today, including the extended meanings of the conventional words and new words create... 详细信息

关键词： neologism broadcast news reporting word formation

Design and Implementation of Distributed broadcast Algorithm Based on Vehicle Density for VANET Safety-Related Messages

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国际计算机前沿大会会议论文集 2017年第2期 62-64页

作者： Wei Wu Zhijuan Li Yunan Zhang Jianli Guo Jing Zhao Science and Technology on Communication Networks Laboratory Shijiazhuang China Harbin Engineering University Harbin Heilongjiang China

Vehicle ad hoc network (VANET) is a research hotspot in industrial and academic fields now and after. Dedicated short-range communication (DSRC) is a key technology of vehicular safety services and most research adhere to IEEE 802.11p standard. The safety-related services face channel congestion, message collision, and hidden tinal problem in different traffic conditions. This paper focuses on the broadcast of safety-related message under different vehicle densities. In this paper, we firstly divide the safety-related messages into three categories and assign them different broadcast priorities. Secondly, we design different distributed broadcast algorithms for the three type messages. Then,we propose a method used to evaluate the vehicle density and present the relationship between the vehicle density and the transmit power. Then the safety module selects proper transmit power according to the relationship before the message is sent. Finally, we conduct the simulation experiment using NS3 software in the Linux environment. Simulation results show that the broadcast scheme can effectively ensure that the emergency message is correctly received in the 200m range for high vehicle density. Compared with the algorithm without considering the vehicle density, the performance has been greatly improved.

关键词： Distributed broadcast Vehicle density Transmit power Transmission distance