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Layered multicast congestion control by particle swarm optimization in heterogeneous environment

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The Journal of China Universities of Posts and telecommunications 2011年第3期18卷 85-91页

作者： MA Hai-yuan MENG Xiang-ru MA Zhi-qiang LI Jin-liang The telecommunication engineering institute Air Force Engineering University Xi'an 710077 China

To enhance multicast throughput in heterogeneous environment, a new layered multicast congestion control scheme is proposed. With the goal of maximizing global satisfaction of the whole group, allocating sending rate in each layer is formulated to an optimization problem. Since the problem is noncovexity, the sender uses particle swarm optimization to search a set of optimal layers rates. The new scheme also eliminates ＇lowest-first＇ phenomenon by proposing a feedbacks suppression algorithm named equal-probability sampling （EPS）. Upon EPS all the receivers send feedbacks at equal probability without bias. Simulation results prove that the new scheme can enhance global satisfaction and multicast throughput efficiently, compared with the traditional layered multicast congestion control scheme based on representatives.

关键词： layered multicast congestion control particle swarm optimization feedbacks suppression

Atomic multicast protocol for intrusion-tolerance based on trusted timely computing base

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The Journal of China Universities of Posts and telecommunications 2009年第6期16卷 97-102页

作者： ZHOU Hua,MENG Xiang-ru,ZHANG Li,QIAO Xiang-dong telecommunication engineering institute,Air Force engineering University,Xi’an 710077,China telecommunication engineering institute Air Force Engineering University Xi'an 710077 China

Distributed architecture is often adopted for the intrusion-tolerance system ***,this distributed intrusiontolerance system has a consensus *** solve this problem,this article explores a distributed intrusion-tolerance system of hybrid time model based on trusted timely computing base（TTCB） and implement an atomic multicast protocol using TTCB *** TTCB is a trust secure real-time component inside the server,with a well defined interface and separated from the operation *** is in the synchronous communication environment,while the application layer in the server works *** the atomic multicast protocol,it can be achieved that when the servers are over twice the number of faulty servers,the consensus can be *** performance evaluations show that the proposed protocol can yield larger good throughput with a lower unavailability.

关键词： Intrusion-tolerance atomic multicast protocol consensus TTCB network security

Gait Recognition by Cross Wavelet Transform and Graph Model

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IEEE/CAA Journal of Automatica Sinica 2018年第3期5卷 718-726页

作者： Sagar Arun More Pramod Jagan Deore Department of Electronics and telecommunication engineering R.C.Patel Institute of Technology

In this paper, a multi-view gait based human recognition system using the fusion of two kinds of features is *** use cross wavelet transform to extract dynamic feature and bipartite graph model to extract static feature which are coefficients of quadrature mirror filter(QMF)-graph wavelet filter bank. Feature fusion is done after normalization. For normalization of features, min-max rule is used and mean-variance method is used to find weights for normalized features. Euclidean distance between each feature vector and center of the cluster which is obtained by k-means clustering is used as similarity measure in Bayesian framework. Experiments performed on widely used CASIA B gait database show that, the fusion of these two feature sets preserve discriminant information. We report 99.90 % average recognition rate.

关键词： Binary sequences feature extraction identification of persons linear discriminant analysis(LDA)

Design and analysis of spectral beam combining system for fiber lasers based on a concave grating

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Optoelectronics Letters 2012年第1期8卷 33-36页

作者：吴卓亮赵尚弘楚兴春张茜占生宝马丽华 telecommunication engineering institute Air Force Engineering University

A novel fiber laser spectral beam combining scheme based on a concave grating is *** principle of the presented system is analyzed,and a concave grating with blazed structure for spectral beam combining is *** combining potential of the system is analyzed,and the results show that 39 Yb-doped fiber laser can be spectrally beam combined via the designed *** using scalar diffraction theory,the combining effect of the system is *** results show that the diffraction efficiency of the designed concave grating is higher than 72% over the whole gain bandwidth,and the combining efficiency is 73.4%.With output power of 1 kW for individual fiber laser,combined power of 28.6 kW can be achieved.

关键词： Diffraction Ytterbium

Quorum systems for intrusion-tolerance based on trusted timely computing base

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Journal of Systems engineering and Electronics 2010年第1期21卷 168-174页

作者： Hua Zhou Xiangru Meng Li Zhang Xiangdong Qiao The telecommunication engineering institute Air Force Engineering University Xi'an 710077 E R. China

Quorum systems have been used to solve the problem of data consistency in distributed fault-tolerance systems. But when intrusions occur, traditional quorum systems have some disadvantages. For example, synchronous quorum systems are subject to DOS attacks, while asynchronous quorum systems need a larger system size （at least 3f＋1 for generic data, and f fewer for self-verifying data）. In order to solve the problems above, an intrusion-tolerance quorum system （ITQS） of hybrid time model based on trust timely computing base is presented （TTCB）. The TTCB is a trust secure real-time component inside the server with a well defined interface and separated from the operation system. It is in the synchronous communication environment while the application layer in the server deals with read-write requests and executes update-copy protocols asynchronously. The architectural hybridization of synchrony and asynchrony can achieve the data consistency and availability correctly. We also build two kinds of ITQSes based on TTCB, i.e., the symmetrical and the asymmetrical TTCB quorum systems. In the performance evaluations, we show that TTCB quorum systems are of smaller size, lower load and higher availability.

关键词： network security intrusion-tolerance quorum system trusted timely computing base (TTCB) consistency availability.

A novel two-layered optical satellite network of LEO/MEO with zero phase factor

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Science China(Information Sciences) 2010年第6期53卷 1261-1276页

作者： LI YongJun , WU JiLi, ZHAO ShangHong, MENG Wen, MA LiHua, SHI Lei, CHU XingChun, HOU Rui & LI Tian telecommunication engineering institute, Air Force engineering University, Xi’an 710077, China telecommunication engineering institute Air Force Engineering University Xi’an China

Optical satellite communication has advantages over the RF satellite communication in capacity, speed, secrecy and *** information superhighway composed of GEO/MEO/LEO satellites which are linked by optical inter-satellite links(OISL) would play important roles in communication, navigation, martial recon, remote sensing and deep space exploration.A novel LEO/MEO two-layered optical satellite network with global coverage is designed with the street-of-coverage *** layer of LEO satellites is the walker-delta constellation with zero phase factor and has the quasi-stable logical structure of *** and polar orbit satellites constitute the layer of MEO satellite, which can cover LEO layer *** satellites of the system can provide 99.9% of coverage for the whole globe and 100% for China *** network can provide a minimum elevation angle at 21 ? with single-satellite visibility for China, and at 16 ? with the dual-satellite *** results of the inter-satellite links show LEO constellation of zero phase factor outperforms non-zero phase factor constellations in azimuth angle, elevation angle and distance, which is very fit for the *** results of the communication performance indicate a little difference between short wave band and long wave band at low communication speed(several Gbit/s);however, the wave band at 1550 nm is a better choice at high communication speed(100 Gbit/s).

关键词： optical satellite communication optical satellite networks constellation design two-layered constellation optical inter-satellite links

Adaptive Three-phase Estimation of Sequence Components and Frequency Using H∞ Filter Based on Sparse Model

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Journal of Modern Power Systems and Clean Energy 2020年第5期8卷 981-990页

作者： Umamani Subudhi Harish Kumar Sahoo Sanjeev Kumar Mishra Department of Electronics and telecommunication engineering Indian Institute of Information Technology(IIIT)BhubaneshwarIndia Department of Electronics and telecommunication engineering Veer Surendra Sai University of Tecnology(Burla)SambalpurIndia

The estimation of sequence or symmetrical components and frequency in three-phase unbalanced power system is of great importance for protection and *** paper proposes a new H∞filter based on sparse model to track the sequence components and the frequency of three-phase unbalanced power *** inclusion of sparsity improves the error convergence behavior of estimation model and hence short-duration non-stationary PQ events can easily be tracked in the time *** proposed model is developed using l1 norm penalty in the cost function of H∞filter,which is quite suitable for estimation across all the three phases of an unbalanced *** model uses real state space modeling across three phases to estimate amplitude and phase parameters of sequence ***,frequency estimation uses complex state space modeling and Clarke transformation generates a complex measurement signal from the unbalanced three-phase *** state vector used for frequency estimation consists of two state *** proposed sparse model is tested using distorted three-phase signals from IEEE-1159-PQE database and the data generated from experimental laboratory *** analysis of absolute and mean square error is presented to validate the performance of the proposed model.

关键词： Sequence component Clarke transformation H∞filter state space model

GENERALIZED THRESHOLD CHASE ALGORITHMS

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Journal of Electronics(China) 1987年第4期4卷 247-253页

作者：王新梅 Northwest telecommunication engineering institute

Three generalized threshold Chase algorithms called GTC Ⅰ,GTC Ⅱ and STC are proposed in *** are the combination of the generalized minimum distance(GMD)decoding algorithm with theChase *** the decoding error probabilities of these algorithms are very close to that of theChase algorithm,the decoding speeds are faster,especially at higher signal-to-noise ratio(SNR),hence theyare of greater practical *** results of computer simulations are given,showing the advantages of thesealgorithms.

关键词： GENERALIZED THRESHOLD CHASE ALGORITHMS

Switched-Beam Optimization for an Indoor Visible Light Communication Using Genetic Algorithm

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Computers, Materials & Continua 2022年第4期71卷 1547-1566页

作者： Ladathunya Pumkaew Monthippa Uthansakul Peerapong Uthansakul School of telecommunication engineering Institute of EngineeringSuranaree University of TechnologyNakhon Ratchasima30000Thailand

Nowadays, Visible Light Communication (VLC) is an attractivealternative technology for wireless communication because it can use somesimple Light Emitting Diodes (LEDs) instead of antennas. Typically, indoorVLC is designed to transmit only one dataset through multiple LED beams at atime. As a result, the number of users per unit of time (throughput) is relativelylow. Therefore, this paper proposes the design of an indoor VLC system usingswitched-beam technique through computer simulation. The LED lamps aredesigned to be arranged in a circular array and the signal can be transmittedthrough the beam of each LED lamp with the method of separating the datasetto increase the number of simultaneous users for enhancing the indoor *** coverage area is determined from the area where the communication canbe performed at a location on the receiving plane with a Bit Error Rate lessthan or equal to the specified value based on coverage illuminance accordingto International Commission on Illumination (CIE) standards. In this paper,Genetic Algorithm is used to find the suitable solution for designing parameters to achieve maximum coverage area. The results show that a GeneticAlgorithm can be used to find a suitable solution and reduce the computationaltime approximately 382 min in proposed scenarios.

关键词： Visible light communication genetic algorithm optimization light emitting diode