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Heuristic based data scheduling algorithm for OFDMA wireless network

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Journal of Systems Engineering and Electronics 2008年第1期19卷 46-51页

作者： Guo Kunqi Sun Lixin Jia shilou Yu Xiaoyang Communication Research Center Harbin Inst. of Technology Harbin 150001 P. R. China Communication Engineering School Harbin Univ. of Science and Technology Harbin 150052 P. R. China

A system model based on joint layer mechanism is formulated for optimal data scheduling over fixed point-to-point links in OFDMA ad-hoc wireless networks. A distributed scheduling algorithm （DSA） for system model optimization is proposed that combines the randomly chosen subcarrier according to the channel condition of local subcarriers with link power control to limit interference caused by the reuse of subcarrier among links. For the global fairness improvement of algorithms, a global power control scheduling algorithm （GPCSA） based on the proposed DSA is presented and dynamically allocates global power according to difference between average carrier-noise-ratio of selected local links and system link protection ratio. Simulation results demonstrate that the proposed algorithms achieve better efficiency and fairness compared with other existing algorithms.

关键词： orthogonal frequency division multiplexing access (OFDMA) scheduling algorithm ad-hoc

Feature-based Image Sequence Compression Coding

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High Technology Letters 2001年第2期7卷 31-33页

作者：周志权 Jia shilou Department of Electronics and Communications Engineering Harbin Institute of Technology

A novel compressing method for video teleconference applications is presented. Semantic-based coding based on human image feature is realized, where human features are adopted as parameters. Model-based coding and the... 详细信息

关键词： Compression coding Model-based Feature-based

Link reliability based hybrid routing for tactical mobile ad hoc network

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Journal of Systems Engineering and Electronics 2008年第2期19卷 259-267页

作者： Xie Xiaochuan Wei Gang Wu Keping Wang Gang Jia shilou School of Electronic & Information Engineering South China Univ. of Technology Guangzhou 510640 P. R. China Guangzhou Haige Communications Group Incorporated Company Guangzhou 510656 P. R. China Communication Research Center Harbin Inst. of Technology Harbin 150001 P. R. China

Tactical mobile ad hoc network （MANET） is a collection of mobile nodes forming a temporary network, without the aid of pre-established network infrastructure. The routing protocol has a crucial impact on the network performance in battlefields. Link reliability based hybrid routing （LRHR） is proposed, which is a novel hybrid routing protocol, for tactical MANET. Contrary to the traditional single path routing strategy, multiple paths are established between a pair of source-destination nodes. In the hybrid routing strategy, the rate of topological change provides a natural mechanism for switching dynamically between table-driven and on-demand routing. The simulation results indicate that the performances of the protocol in packet delivery ratio, routing overhead, and average end-to-end delay are better than the conventional routing protocol.

关键词： tactical mobile ad hoc networks hybrid routing link reliability edge weight.

Identification of VC merging source during multipoint-to-point communication

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Journal of Harbin Institute of Technology(New Series) 2002年第3期9卷 276-279页

作者： ZOU Xinguang(邹昕光) JIA shilou(贾世楼) Communication Research Center Harbin Institute of Technology Harbin 150001 China Communication Research Center Harbin Institute of Technology Harbin 150001 China

The VC merging algorithm is used widely for multipoint to point ATM communication. For AAL5 lacking multiplex ID field, the downstream receiving point cannot distinguish the multiplexed source in a multipoint to point VC after VC merging. So the source based rate distribution algorithms cannot work properly. We designed a source detection algorithm to enable the switch to know the number of sources and the cell rate of each source in a multipoint to point VC. These information is very important for the source based rate distribution algorithm. We used the ERICA algorithm in our simulations and the simulations demonstrated the proper operation of the source detection algorithm.

关键词： multipoint-to-point, VC merging , source detection, source based rate distribution

Efficiency-aware and fairness-aware joint-layer optimization for downlink data scheduling in OFDM

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Science in China(Series F) 2008年第2期51卷 171-182页

作者： GUO KunQi SUN LiXin WANG Ping JIA shilou Shanghai Research Center for Wireless Communications Shanghai Institute of Microsystem and Infor- mation Technology Chinese Academy of Sciences Shanghai 200050 China School of Measurement & Control Technology and Communication Engineering Harbin University of Science and Technology Harbin 150080 China Communication Research Center Harbin Institute of Technology Harbin 150001 China

Efficiency and fairness are two crucial issues to be considered for resource alloca- tion in multi-user wireless networks. Based on the joint optimization of physical layer and data link layer, an optimization model is derived to achieve efficient and fair downlink data scheduling in multi-user OFDM wireless networks by maximizing the total utility function with respect to the average waiting time of user queue. A dynamic sub-carrier allocation algorithm （DSAA） based on the optimization model is proposed in order to obtain the maximization of the total scheduling utility. Effi- ciency is improved by combining DSAA with time scale interference predictor （TSIP） which at large time scales predict ON/OFF period of user data with temporal corre- lation structure across multiple time scales in multi-user interference environment. Simulation results verify the efficiency and fairness of the scheme.

关键词： OFDM efficiency and fairness joint-layer scheduling utility function

Performance Analysis of Cell Loss Probability Based on ATM Self-healing Multi-section-backup VP Scheme

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High Technology Letters 2001年第4期7卷 54-57页

作者：陶立南 Jia shilou Communications Research Center Harbin Institute of Technology

Based on ATM Multi section backup VP self healing scheme, analysis of cell loss probability under finite buffer is made by use of queue system method. Optimal buffer size can be fixed on.

关键词： Cell loss probability Multi section backup VP Self healing

Experimental study of midazolam as probe on evaluating activity of inhibited hepatic CYP3A

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中国药理通讯 2005年第2期22卷 32-33页

作者： Xue-huiZHU Jian-jieJIAO Jian-shilou TianjinMedicalUniversity 300070

AIM To study the effect of ketoconazole (KTZ), a selective inhibitor of CYP3A, on in vivo and in vitro metabolic activity of hepatic CYP3A in rat with midazolam (MDZ) as probe, which was assessed by pharmacokinetic parameters of MDZ., and to establish a suitable marker or indicator for estimating drugmetabolizing activity of hepatic CYP3A. METHODS 1. In vivo study: Several loading doses of KTZ prepared in a mixture of PEG400 and propylene glycol (9:1) were administrated through rat sublingual vein followed by constant infusion at different rates through tail vein with an attempt to achieve corresponding steady-state plasma concentrations in order to attain continuous inhibition on CYP3A.

关键词：咪达唑仑实验研究探测器活动性肝脏 CYP3A KTZ

多光储虚拟同步发电机接入多机电力系统的动态交互作用机理分析

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高电压技术 2022年第9期48卷 3710-3722页

作者：黄世楼王彤金铭鑫焦典华北电力大学新能源电力系统国家重点实验室北京102206

随着新能源友好并网技术和储能技术的大力发展,光储虚拟同步发电机将具有广阔的发展前景。然而,多光储虚拟同步发电机与多机电力系统间动态交互作用机理尚未明确,可能引起的振荡问题将给电网稳定运行带来较大风险。首先建立多光储虚拟... 详细信息

随着新能源友好并网技术和储能技术的大力发展,光储虚拟同步发电机将具有广阔的发展前景。然而,多光储虚拟同步发电机与多机电力系统间动态交互作用机理尚未明确,可能引起的振荡问题将给电网稳定运行带来较大风险。首先建立多光储虚拟同步发电机子系统和多机电力系统子系统的状态空间模型及其传递函数模型。然后,建立两个子系统间动态交互作用模型,推导多光储虚拟同步发电机向多机电力系统提供的阻尼转矩,分析其动态交互作用的路径和机理。最后,以多光储虚拟同步发电机接入4机2区系统和10机39节点系统为算例,详细分析光储系统采用虚拟同步控制前后和虚拟同步控制参数对动态交互作用的影响规律,结合系统特征值分析和时域仿真验证分析结论的正确性。

关键词：多光储虚拟同步发电机动态交互作用多机电力系统机理分析交互路径传递函数

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基于GAIC的MIMO-OFDM信道估计

数据采集与处理 2008年第B9期23卷 92-95页

作者：赵俊义贾世楼孟维晓哈尔滨工业大学通信技术研究所哈尔滨150001

对于多径稀疏的多输入多输出正交频分复用(Multiple-input and multiple-output orthogonal frequency di-vision multiplexing,MIMO-OFDM)信道,提出了基于广义Akaike信息论准则(Generalized Akaike informationcriterion,GAIC)的MIMO-OFDM系统实用的信道估计算法,该算法能够估计出信道的长度和每径信道的时延,降低加性白噪声对信道估计的影响,提高信道估计的精度。通过仿真,与最小二乘(Least squares,LS)算法和离散傅里叶变换(Discrete Fourier transform,DFT)算法相比较,大大地降低了信道的估计误差,提高了系统性能,且信道稀疏性越强,性能改善越好。

关键词：信道估计稀疏多径信道广义Akaike信息论准则多输入多输出正交频分复用