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Routing Protocol with Optimal Location of Aggregation Point in Wireless Sensor Networks

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The Journal of China Universities of Posts and Telecommunications 2006年第1期13卷 1-5页

作者： LIU yue-yang ji Hong yue Guang-xin School of Telecommunications Engineering Beijing University of Posts and Telecommunications Beijing 100876 P.R. China

A wireless sensor network is typically composed of hundreds, even thousands of tiny sensors used to monitor physical phenomena. As data collected by the sensors are often redundant, data aggregation is important for conserving energy. In this paper , we present a new routing protocol with optimal data aggregation. This routing protocol has good performance due to its optimal selection of aggregation point locations. This paper details the optimal selection of aggregation point locations.

关键词： wireless sensor networks routing protocol data aggregation

Novel disjoint path selection scheme based on link availability in ASON

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The Journal of China Universities of Posts and Telecommunications 2007年第3期14卷 70-73页

作者： WANG Xian-qing LU yue-ming ji yue-feng Key Laboratory of Optical Communication and Lightwave Technologies Ministry of Education Beijing University of Posts and TelecommunicationsBeijing 100876 China

Risk-disjoint routing is an efficient way to improve network survivability. In this article, a partial risk-disjoint routing algorithm based on link availability （PRDRA-LA） is proposed based on the complete risk-disjoint routing algorithm （CRDRA）. While calculating the protection path with PRDRA-LA, the links that share risks with the links in the working path are filtered by link availability. In addition, the risk disjoint degree between the protection path and the working path can be adjusted freely. Simulation results showed that when compared with CRDRA, routing connections with PRDRA-LA can achieve improved survivability while the number of connections that can be successfully routed over the current network is kept from serious decline.

关键词： automatically switched optical network risk- sharing links partial risk-disjoint routing algorithm based on link availability risk-disjoint degree

Model analysis and resonance suppression of wide-bandwidth inertial reference system

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Nanotechnology and Precision Engineering 2019年第4期2卷 177-187页

作者： Dong Li TengfeiWu yue ji Xingfei Li State Key Laboratory of Precision Measurement Technology and Instruments Tianjin UniversityTianjin 300072China Key Laboratory of Advanced Electrical Engineering and Energy Technology Tianjin Polytechnic UniversityTianjin 30087China

In the fields of earth observation,deep space detection,laser communication,and directional energyweapon,the target needs to be observed and pointed at ***,tracking,and pointing(ATP)systems are usually designed to stabilize the line of sight(LOS)within sub-micro radian *** the case of an ATP system mounted on a mobile platform,angular disturbances experienced by the mobile platform will seriously affect the *** overcome the problemthat the sampling frequency of detectors is usually limited and achieving several hundreds of hertz is difficult,thewide-bandwidth inertial reference system(WBIRS)and fast steeringmirror are usually integrated into ATP systems to mitigate these angular *** reduce the structural stress,a flexible support providing two rotational degrees of freedomis usually adopted for the ***,the occurrence of resonant points within the bandwidthwill be *** have to be taken to compensate these low-frequency resonant points to realize a wide bandwidth and high *** this paper,the lowfrequency resonant points of a systemwere simulated using finite element analysis and tested by a systemidentification *** results show that the first-order resonance happened at 34.5 Hz with a gain of 28 *** improved double-T notch filter was designed and applied in a real-time system to suppress the resonance at 34.5 *** experimental results show that the resonance was significantly *** particular,the resonance peak was reduced by 79.37%.In addition,the closed-loop system settling time was reduced by 36.2%.

关键词： Resonance suppression Notch filter System identification Inertial reference

Flexible scheduling ensuring inter-ONU-group fairness in 1G/10G EPON coexistence system

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The Journal of China Universities of Posts and Telecommunications 2009年第4期16卷 16-22页

作者： LI Qi LI Hui ji yue-feng Key Laboratory of Optical Communications and Lightwave Technologies Beijing University of Posts and Telecommunications Beijing 100876 China

In recent years, 10 Gbit/s Ethemet passive optical networks （10G EPON） have been gaining considerable interests because of its high bandwidth capability. To ensure smooth transition from 1 Gbit/s to 10 Gbit/s equipment and to avoid a significant one-time investment into such a cost-sensitive market, coexistence of gigabit Ethernet passive optical networks （GEPON） and 10G EPON system are necessary. In this article, coexistence system architecture and a novel bandwidth allocation algorithm called weight-optimized dynamic bandwidth allocation for coexistence EPON （WOCE-DBA） for the system is proposed. The simulation results show that this algorithm can guarantee fair bandwidth sharing among different optical network unit （ONU） groups, without ignoring the inter-ONU and intra-ONU fairness. Most importantly, it can flexibly adapt to the system composition variations and save efforts needed to modify the bandwidth scheduling mechanism during the migration process from GEPON to 10G EPON.

关键词： 10G EPON coexistence system dynamic bandwidth allocation (DBA) intra-ONU-group fairness simulation and modeling

Supporting multi-user real-time VBR video service using dynamic bandwidth management based on prediction

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The Journal of China Universities of Posts and Telecommunications 2009年第6期16卷 64-71页

作者： XU Zhi-yuan LI Hui LU yue-ming ji yue-feng Key Laboratory of Optical Communications and Lightwave Technologies Beijing University of Posts and Telecommunications Beijing 100876 China

Real-time variable bit rate（VBR） video is expected to take a significant portion of multimedia ***,plentiful challenges to VBR video service provision have been raised for its characteristic of high traffic *** support multi-user real-time VBR video transmission with high bandwidth utilization and satisfied quality of service（QoS）,this article proposes a practical dynamic bandwidth management *** scheme forecasts future media rate of VBR video by employing time-domain adaptive linear predictor and using media delivery index（MDI） as both QoS measurement and complementary management *** addition,to support multi-user application,an adjustment priorities classified strategy is also put ***,a test-bed based on this management scheme is *** experimental results demonstrate that the scheme proposed in this article is efficient with bandwidth utilization increased by 20%-60% compared to a fixed service rate and QoS guaranteed.

关键词： dynamic bandwidth management MDI QoS real-time time-domain adaptive linear predictor VBR video

Fabrication and properties of Al matrix composites strengthened by in situ alumina particulates

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Journal of University of Science and Technology Beijing 2006年第3期13卷 263-266页

作者： Gaofeng Fu Lan jiang ji Liu yue Wang School of Materials and Metallurgy Northeastern University Shenyang 110004 China

New aluminum matrix composites strengthened by Al2O3 particulates through stirring cast by adding NH4Al（SO4）2 to the molten aluminum have been fabricated. TEM observation shows that in-situ Al2O3 particulates are generally spherical and they are uniformly distributed in the Al matrix. Dry sliding wear test results show that the volume loss of the unreinforced Al matrix is about three times that of the Al2O3 reinforced metal matrix composite （MMC） and the volume loss of the MMC fabricated by adding Al2O3 is larger than that of the MMC by adding NH4Al（SO4）2. Lubricating sliding wear test results show that the volume loss of the MMCs increases more slowly than that of the matrix with the increasing of the load.

关键词： aluminum matrix composite alumina microstructure wear

Non-interference topology scheme in wireless sensor networks

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The Journal of China Universities of Posts and Telecommunications 2007年第2期14卷 7-13页

作者： MA Shu-hui ji Hong yue Guang-xin School of Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

A novel topology scheme, cell with multiple mobile sinks method （CMMSM）, is proposed in this article for the collection of information and for the environment monitoring in wireless sensor networks. The system consists of many static sensors, scattered in a large scale sensing field and multiple mobile sinks, cruising among the clusters. Conservation of energy and simplification of protocol are important design considerations in this scheme. The noninterference topology scheme largely simplifies the full-distributed communication protocol with the ability of collision avoidance and random routing. The total number of cluster heads in such a topology was analyzed, and then an approximate evaluation of the total energy consumption in one round was carded out. Simulation results show that CMMSM can save considerable energy and obtain higher throughput than low-energy adaptive clustering hierarchy （LEACH） and geographical adaptive fidelity （GAF）.

关键词： sensor networks energy consumption topology design multiple mobile sinks

QoS multicast routing scheme using QGA in IP/DWDM networks

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The Journal of China Universities of Posts and Telecommunications 2008年第4期15卷 95-100页

作者： XING Huan-lai BAI Lin ji yue-feng Key Laboratory of Optical Communications and Lightwave Techno ogies Beijing University of Posts and Telecommunications Beijing 100876 China

This article studies multi-constraints least-cost multicast routing problem in internet protocol over dense wavelength division multiplexing （IP/DWDM） networks. To address this problem, an individual-difference-based quantum genetic algorithm （IDQGA） is proposed. This algorithm considers individual differences among chromosomes by introducing an adaptive rotation angle step determination scheme and a grouping-based quantum mutation operation. Simulations are conducted over network topologies. The results indicate that compared with other heuristic algorithms, IDQGA has better optimal performance on solving quality of service （QoS） multicast routing problem in IP/DWDM networks and is characterized by strong robustness, high success ratio and excellent capability on global searching.

关键词： IP-over-DWDM multicast QoS quantum genetic algorithm

Chemical composition,sensory properties and application of Sichuan pepper(Zanthoxylum genus)

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Food Science and Human Wellness 2019年第2期8卷 115-125页

作者： yue ji Shiming Li Chi-Tang Ho Department of Food Science Rutgers University65 Dudley RoadNew BrunswickNJ08901USA

This review summarized the composition of volatile and nonvolatile compounds,the sensory mechanism and the application of Sichuan pepper(Zanthoxylum genus)as a spice and multifunctional food,such as antibacterial,inhibition of inflammation,and antioxidant among *** aim is to provide a better understanding and potential future in-depth research and application of Sichuan pepper.

关键词： Sichuan pepper Zanthoxylum Volatile flavor compounds Pungent taste Alkyl amides