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Broadband hybrid model for relay-aided cooperative MIMO power line communication systems

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The Journal of China Universities of Posts and Telecommunications 2020年第1期27卷 72-80页

作者： Liang xiaolin Cao Wangbin School of Electronic and Information Engineering Hebei UniversityBaoding 071002China School of Electrical and Electronic Engineering North China Electric Power UniversityBaoding 071000China

A hybrid model for broadband multiple-input multiple-output(MIMO) relay-aided indoor power line communications(PLC) system was proposed in this paper. The proposed model combines the top-down and bottom-up approaches and extends to a two-hop relay-aided cooperative system with variable gain relay in amplify-and-forward(AF) mode. Based on the proposed PLC model and generated channel, the channel statistical characteristics are further investigated in 2 MHz^100 MHz bandwidth. Simulated results show that the proposed model overcomes the difficulties that the existing models need a lot of topological information of the network or measurements information. It provides a practical simulation analysis method for cooperative relay MIMO-PLC system. The results also show that cooperative MIMO relaying communications can improve the indoor PLC performances and communication reliability.

关键词： broadband communication channel frequency response(CFR) hybrid model MIMO-PLC power line communications(PLC) relay-aided

Exploring the latest Pantheon SN Ia dataset by using three kinds of statistics techniques

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Communications in Theoretical Physics 2021年第4期73卷 92-98页

作者： Shuang Wang xiaolin Luo School of Physics and Astronomy Sun Yat-Sen UniversityGuangzhou 510297China

In this work,we explore the cosmological consequences of the latest Type Ia supernova(SN Ia)dataset,Pantheon,by adopting the wCDM *** Pantheon dataset currently contains the largest number of SN Ia samples,which contains 1048 supernovae on the redshift range 0bines the advantages of MS and *** should be mentioned that the IFS technique needs to scan the(zcut,Δz)parameters plane,where zcut andΔz are redshift cut-off and redshift interval of FA,*** results are as follows.(1)Using the SN dataset only,the best FA recipe for IFS is(zcut,Δz)=(0.1,0.08);(2)comparing to the old SN dataset,JLA,adopting the Pantheon dataset can reduce the 2σerror bars of equation of state w by 38%,47%and 53%for MS,FS and IFS,respectively;(3)FS gives closer results to other observations,such as Baryon acoustic oscillations and cosmic microwave background;(4)compared with FS and IFS,MS more favors a Universe that will end in a‘big rip’.

关键词： Dark Energy Type Ia supernova Cosmological Observations

Proportional rate scheduling based on QoS in mobile WiMAX networks

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Journal of Systems Engineering and Electronics 2009年第6期20卷 1332-1335页

作者： Fang Lintang Zhang xiaolin School of Electronic and Information Engineering Beihang Univ. Beijing 100191 P. R. China

A new scheduling scheme based on users＇ quality of service（QoS） in mobile WiMAX networks is *** proposed scheme tracks each user＇s average rate and adjusts the corresponding scheduling weight adaptively to result in：（a） each user＇s average rate is proportional to the corresponding QoS level;（b） the constraints of the minimal and/or maximal rates required by QoS can be satisfied;（c） the utility function of system is maximal under the constraints（a） and（b）.Theoretical analysis based on utility function and simulation results indicates the system throughput can be improved dramatically in the proposed scheme.

关键词： mobile WiMAX quality-of-service scheduling utility function.

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中药制剂口服吸收生物利用度改善方法探讨

世界科学技术-中医药现代化 2009年第6期11卷 772-776页

作者：恽菲狄留庆蔡宝昌赵晓莉毕肖林王令充陶金华杜秋南京中医药大学南京210029

本文通过文献研究并结合实验室工作成果,以中药活性成分口服吸收机制为出发点,提出通过改善难溶性中药活性成分的溶解度和溶出速度、控制中药活性成分在胃肠道中代谢、改善中药活性成分的胃肠吸收和转运、发挥中药组合活性成分之间的有... 详细信息

本文通过文献研究并结合实验室工作成果,以中药活性成分口服吸收机制为出发点,提出通过改善难溶性中药活性成分的溶解度和溶出速度、控制中药活性成分在胃肠道中代谢、改善中药活性成分的胃肠吸收和转运、发挥中药组合活性成分之间的有益影响等方式提高中药活性成分的口服吸收生物利用度。

关键词：中药活性成分口服生物利用度药剂学技术

Multi–physical-field characteristics modeling and structure optimization for kW-level ultra-high-speed PM motors with integrated support system

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Chinese Journal of Aeronautics 2023年第4期36卷 455-467页

作者： Qixing GAO xiaolin WANG Yan ZHANG College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China School of Intelligence Science and Control Engineering Jinling Institute of TechnologyNanjing 211169China

In the aerospace industry,the low-mass ultra-high-speed flywheel system play a critical *** this paper,a kW-level Ultra-High Speed Permanent Magnet Synchronous Motor(UHSPMSM)as the core component of flywheel system is proposed and analyzed with consideration of multiple physical fields,including electromagnetic characteristics,mechanical strength and rotor *** integrated support structure is put forward to improve rotation accuracy and operation stability of the ***,influence of the integrated support structure on critical speed is explored,and the key parameters such as support position and support stiffness are ***,the rotor strength is analyzed by analytical model developed of rotor stress that can deal with multiple boundary *** and thickness of the sleeve are optimized,and range of interference value is accurately limited based on four extreme operating *** 3-D Finite Element Model(FEM)is used to validate the strength characteristics and stress distribu-tion of rotor.A 1.5 kW-150000 r/min UHSPMSM with integrated support system is manufactured and *** feasibility of UHSPMSM proposed and the accuracy of analysis method are verified through electromagnetic,temperature rise and vibration characteristics *** machine prototype realizes the load operation at rated speed and the multi-physical-field characteristics achieve the design specification.

关键词： Flywheel energy storage Integrated support system Multi–physical-field charac-teristics Mechanical strength Rotor dynamics Ultra-high-speed motor

Single Sample Polarization Filtering

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Journal of Systems Engineering and Electronics 1992年第1期3卷 45-55页

作者： xiaolin, Qiao Yongtan, Liu Harbin Inst. of Tech. Harbin China

A new method on radar signal polarization filtering using only single sample of signal is proposed. The algorithm is very simple and it is suitable for the filtering processing of a stationary or unstationary polariza... 详细信息

关键词： Radar measurement Signal Processing

GALERKIN BOUNDARY NODE METHOD FOR EXTERIOR NEUMANN PROBLEMS

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Journal of Computational Mathematics 2011年第3期29卷 243-260页

作者： xiaolin Li Jialin Zhu College of Mathematics Science Chongqing Normal University Chongqing ~000~7 China College of Mathematics and Physics Chongqing University Chongqing 400044 China

In this paper, we present a meshless Galerkin scheme of boundary integral equations （biEs）, known as the Galerkin boundary node method （GBNM）, for two-dimensional ex- terior Neumann problems that combines the moving least-squares （MLS） approximations and a variational formulation of biEs. In this approach, boundary conditions can be imple- mented directly despite the MLS approximations lack the delta function property. Besides, the GBNM keeps the symmetry and positive definiteness of the variational problems. A rigorous error analysis and convergence study of the method is presented in Sobolev spaces. Numerical examples are also given to illustrate the capability of the method.

关键词： Meshless Galerkin boundary node method Boundary integral equations Moving least-squares Error estimate.

A Dual-Satellite GNSS Positioning Algorithm of High Accuracy in Incomplete Condition

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China Communications 2016年第10期13卷 58-68页

作者： bing Hou xiaolin Zhang Shanghai Engineering Center for Microsatellites Shanghai 201203 China Beihang University Beijing 100191 China

Global navigation satellite system could provide accurate positioning results in signal complete condition. However, the performance is severe when signal denied, especially for the single-mode Bei Dou receiver. This paper proposes a dual-satellite positioning algorithm to promote the positioning performance in the satellite signal gap. The new algorithm utilizes the previous positioning data stored in complete condition to simplify the positioning equations. As the clock bias persists for a short period, this proposed method could work out accurate positioning results by only two visible satellites, without the need of computing the clock bias. Also, the Kalman filtering algorithm is used to smooth the trajectories, and improve the positioning results. During the incomplete period, only two satellites for 30 seconds and three satellites for 60 seconds, the preliminary experiment result shows that, the presented method could provide almost the same positioning results as in complete condition.

关键词： Bei Dou navigation satellite system incomplete condition dual-satellite positioning algorithm kalman filtering

Experimental Investigation on Flame Characterization and Temperature Profile of Single/Multiple Pool Fire in Cross Wind

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Journal of Thermal Science 2021年第1期30卷 324-332页

作者： CHEN Zhen WEI xiaolin LI Teng Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Energy and Power EngineeringTsinghua UniversityBeijing 100084China State Key Laboratory of High Temperature Gas Dynamics Institute of MechanicsChinese Academy of SciencesBeijing 100190China

An experimental study was carried out to investigate the flame characterization and temperature profile for single and multiple pool fire with the influence of cross *** were 13 test cases in total,categorized into circle and rectangle fuel pans,with diameter(or equivalent diameter)ranged from 50 mm to 300 *** was used for the fuel of pool *** K-type thermocouples were arranged around the flame to monitor the flame temperature,while the flame tilt angle was measured based on the photograph of flame for different ***,it can be found that there are three phases,including preheating,steady burning and extinguishing phase,during the flame *** maximum temperature near the fuel surface is~1040 K,which is higher than that of flame plume(~600 K),in the steady burning phase of circle single pool fire(D=300 mm),while the average burning rate is~1.525 g/*** addition,the burning rates of all cases were measured and compared with the current predicted ***,the flame morphology of single/multiple pool fire at different cross wind speed(ranging from 0 to 3.5 m/s)was analyzed,and it is found that the results for single pool fire agree with Thomas model and AGA model well,which are not suitable for multiple pool ***,the temperature profile of different case was measured with various wind speed.

关键词： pool fire temperature profile flame characteristic kerosene cross wind