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DS-CDMA system outer loop power control and improvement for multi-service

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Journal of Systems Engineering and Electronics 2008年第3期19卷 453-460页

作者： Guan Mingxiang guo qing Li Xing School of Electronic and Information Technology Harbin Inst. of Technology Harbin 150001 P.R. China Huawei Technologies Co. Ltd Shenzhen 518057 P. R. China

When a new user accesses the CDMA system, the load will change drastically, and therefore, the advanced outer loop power control （OLPC） technology has to be adopted to enrich the target signal interference ratio （Silt） and improve the system performance. The existing problems about DS-CDMA outer loop power control for multi-service are introduced and the power control theoretical model is analyzed. System simulation is adopted on how to obtain the theoretical performance and parameter optimization of the power control algorithm. The OLPC algorithm is improved and the performance comparisons between the old algorithm and the improved algorithm are given. The results show good performance of the improved OLPC algorithm and prove the validity of the improved method for multi-service.

关键词： DS-CDMA outer loop power control multi-service performance.

SU(3) Simple Group Model and New Z' Properties in Future Linear Colliders

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Communications in Theoretical Physics 2009年第2期51卷 299-304页

作者： LIU Yao-Bei WANG shuai-Wei ZHANG Wen-qing Henan Institute of Science and Technology Xinxiang 453003 China Department of Physics Nanyang Normal University Nanyang 473061 China

In the SU（3） simple group model, the new neutral gauge boson Z＇ couples to pairs of SM fermions with couplings fixed in terms of the SM gauge couplings and depending only on the choice of the fermion embedding. In this paper, we calculate the contributions of this new particle to the processes e^＋e^-→l^＋l^-, bb^-, and cc^- and study the possibility of detecting this new particle via these processes in the future high-energy linear e^＋e^- collider（LC） experiments with √s= 500 GeV and ￡int= 340 fb^-1. We find that the new gauge boson Z＇ is most sensitive to the process e^＋e^-→b^＋b^-. As long as Mz,≤2 TeV , the absolute values of the relative correction parameter are larger than 5%. We calculate the forward-backward asymmetries and left-right asymmetries for the process e^＋e^-→c^＋c^-, with both the universal and anomaly-free fermion embeddings. Bounds on Z＇ masses are also estimated within 95% confidence level.

关键词： SU(3) simple group model relative corrections forward-backward asymmetry left-right asymme-try new gauge boson

Characteristics of regional climate change and pattern analysis on Ordos Plateau

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Journal of Environmental Sciences 2002年第4期14卷 568-576页

作者： LI guo qing ZHENG Yuan run Laboratory of Quantitative Vegetation Ecology Institute of BotanyChinese Academy of SciencesBeijing 100093China.

The characteristics of precipitation, temperature and their combination determine the special ecological environment pattern of Ordos Plateau. Analyzing its evolutionary trend attributes to understanding the succession process of the ecological environment of Ordos Plateau and has crucial instructional significance on the ecological restoration research being conducted in this region. Four time scales, arranging from ten days, one month, one season(growing season contrasting to non growing season)to one year were adopted to analyze the climate data which included nearly 30 years and were collected by eight weather stations on Ordos Plateau. The results indicated that the mean annual temperature and the mean monthly temperature of February, September and December, had increased significantly during the late 30 years. The annual precipitation did not show significant changes but its distribution pattern had changed obviously. The ratio of precipitation of major growing season (May October)to annual precipitation had increased distinctively,and five counties' precipitation reached statistically significant level. And the ratio of precipitation of latter growing season (September)to one year decreased significantly while the ratio of non growing season(November next April)to one year changed insignificantly. The results showed that maybe the interaction of increased mean temperature and insignificant change of precipitation in non growing season was one of the reasons why the desertification of the region was deteriorating in recent years. Using some factors closely relating to vegetation succession such as mean annual temperature, mean annual precipitation, distributive pattern of precipitation, mean temperature of the coldest month, mean temperature of the warmest month, precipitation of the warmest month, mean temperature of growing season, precipitation of growing season, potential evapotranspiration(PET)and radiative dryness index(RDI), to synthetically anal

关键词： climate change climatic synthetical regionalization restoration ecology Ordos Plateau

Densification and properties of ODS-iron based alloy

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Rare Metals 2012年第4期31卷 339-342页

作者： guo, Zhimeng Liu, qing Yang, Weiwei guo, Leichen Institute of Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China College of Animal Science & Technology China Agricultural UniversityBeijing 100193China

Y_2O_3 dispersion strengthened iron-based powders and oxide dispersion strengthened(ODS) alloys were prepared by hydrothermal synthesis and spark plasma sintering(SPS),*** effects of Y_2O_3,vibratory milling treatment,and Ti element on the microstructure and mechanical properties of the materials were investigated by scanning electron microscope(SEM) and micro-electronic universal *** results show that the best mechanical properties are obtained with 1 wt.% Y_2O_3 *** size of agglomerated particles can be decreased to a certain degree by vibratory milling *** the addition of Ti element,the tensile strength and hardness of the samples were improved.

关键词： oxide dispersion strengthened(ODS) hydrothermal synthesis spark plasma sintering(SPS) mechanical properties

股总动脉斑块稳定性联合颈动脉斑块最大厚度检测对老年急性脑梗死复发的预测价值

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陕西医学杂志 2025年第1期54卷 57-61页

作者：苗涛卫国赵清空军军医大学第一附属医院陕西西安710032 空军军医大学空军第九八六医院干部病房陕西西安710054

目的:探讨股总动脉斑块稳定性联合颈动脉斑块最大厚度对老年急性脑梗死复发的预测价值。方法:前瞻性选择256例老年急性脑梗死患者为研究对象,按照发病后1年内是否复发分为复发组和未复发组。收集所有患者基线资料与超声指标,采用非条件... 详细信息

目的:探讨股总动脉斑块稳定性联合颈动脉斑块最大厚度对老年急性脑梗死复发的预测价值。方法:前瞻性选择256例老年急性脑梗死患者为研究对象,按照发病后1年内是否复发分为复发组和未复发组。收集所有患者基线资料与超声指标,采用非条件二分类Logistic回归分析影响脑梗死复发的相关因素。绘制受试者工作特征(ROC)曲线分析此类超声指标对脑梗死复发的预测价值。结果:与非复发组比较,复发组糖尿病史、入院卒中量表(NIHSS)评分、收缩压、低密度脂蛋白胆固醇(LDL-C)、C反应蛋白、D-二聚体、股总动脉斑块易损评分、股总动脉颈动脉内中膜厚度(IMT)、颈动脉斑块最大厚度、颈动脉IMT均较高,差异有统计学意义(均P<0.05)。多因素Logistic回归分析显示,股总动脉斑块易损评分、颈动脉斑块最大厚度是影响老年急性脑梗死复发的独立危险因素(均P<0.05)。ROC分析显示,股总动脉斑块易损评分、颈动脉斑块最大厚度预测脑梗死复发的曲线下面积(AUC)分别为0.752,0.814,灵敏度分别为69.28%和77.80%;特异度分别为84.35%和82.82%,最佳诊断值分别为4.65分和2.78 mm。两者联合预测的AUC为0.903,明显高于前两者(均P<0.05)。结论:股总动脉斑块稳定性、颈动脉斑块最大厚度与老年急性脑梗死复发具有相关性,两者联合检测对脑梗死复发具有良好的预测价值,有助于脑梗死复发的高危人群进行鉴别和危险分层。

关键词：股总动脉斑块稳定性颈动脉斑块最大厚度脑梗死复发预测价值老年人

Experimental study on influence of operating parameters on tar components from corn straw gasification in fluidized bed

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Frontiers in Energy 2021年第2期15卷 374-383页

作者： shuai guo Xiao WEI Deyong CHE Hongpeng LIU Baizhong SUN School of Energy and Power Engineering Northeast Electric Power UniversityJilin 132012China

Gasification is a promising approach for converting solid fuel sources, including renewable ones like biomass, for use. The main problem in biomass gasification is the formation of condensable tars, including polycyclic aromatic hydrocarbons (PAHs). This paper investigated the conversion of tar components during corn straw gasification. It analyzed collected tar components using a gas chromatograph-mass spectrograph (GC-MS). Experimental results indicate that, with increasing temperature from 700°C to 900°C, the concentrations of benzene, indene, phenanthrene, naphthalene, acenaphthylene, fluorene, and pyrene increased whereas those of toluene, phenol, 1-methylnaphthalene, and 2-methylnaphthalene decreased. As the equivalence ratio (ER) increased from 0.21 to 0.34, the concentrations of indene and phenanthrene increased from 0.148% and 0.087% to 0.232% and 0.223%, respectively. Further, the phenol content increased as ER increased from 0.21 to 0.26 and then decreased as the ER increased further to 0.34. Other parameters like the steam/biomass (S/B) ratio and catalyst also played a critical role in tar reduction. This paper demonstrates the conversion of some tar components and elucidates their chemical properties during gasification.

关键词： gasification tar components operating parameters

Configuration and Kinematics of a 3-DOF Generalized Spherical Parallel Mechanism for Ankle Rehabilitation

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 176-188页

作者： Jianjun Zhang shuai Yang Chenglei Liu Xiaohui Wang Shijie guo School of Mechanical Engineering Hebei University of TechnologyTianjin 300401China Key Laboratory of Robot Perception and Human-Machine Fusion Tianjin 300401China

The kinematic equivalent model of an existing ankle-rehabilitation robot is inconsistent with the anatomical structure of the human ankle,which influences the rehabilitation ***,this study equates the human ankle to the UR model and proposes a novel three degrees of freedom(3-DOF)generalized spherical parallel mechanism for ankle *** parallel mechanism has two spherical centers corresponding to the rotation centers of tibiotalar and subtalar *** screw theory,the mobility of the parallel mechanism,which meets the requirements of the human ankle,is *** inverse kinematics are presented,and singularities are identified based on the Jacobian *** workspaces of the parallel mechanism are obtained through the search method and compared with the motion range of the human ankle,which shows that the parallel mechanism can meet the motion demand of ankle ***,based on the motion-force transmissibility,the performance atlases are plotted in the parameter optimal design space,and the optimum parameter is obtained according to the demands of practical *** results show that the parallel mechanism can meet the motion requirements of ankle rehabilitation and has excellent kinematic performance in its rehabilitation range,which provides a theoretical basis for the prototype design and experimental verification.

关键词： Ankle rehabilitation Parallel mechanism Kinematic analysis Parameter optimization

Novel optimized routing algorithm for LEO satellite IP networks

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Journal of Systems Engineering and Electronics 2011年第6期22卷 917-925页

作者： Zihe Gao qing guo Zhenyu Na Communication Research Center Harbin Institute of Technology Harbin 150001 E R. China School of Information Science and Technology Dalian Maritime University Dalian 116026 E R. China

A lot of routing algorithms have been proposed for low earth orbit（LEO） satellite IP networks in recent years,but most of them cannot achieve global *** dynamic characters of LEO satellite networks are reflected in two aspects：topology and traffic *** algorithms mentioned above are ＂hard routing＂ which only realize local optimization.A distributed soft routing algorithm combined with multi-agent system（MASSR） is *** MASSR,mobile agents are used to gather routing information actively,and blackboard is introduced to achieve direct information exchange between *** provides traffic adaptive routing and tracks the change of LEO satellite network *** performance of ant colony optimization（ACO） and MASSR are compared in Iridium constellation,and MASSR presents better end-to-end delay as well as enhanced robustness.

关键词： distributed routing multi-agent system(MAS) satellite IP networks.

Research on three-dimensional trajectory parameter measurement of industrial products

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仪器仪表学报 2007年第6期28卷 999-1002页

作者： guo qing guo Ming Hu Jingquan Hu Hongzhi Guilin University of Electronic Technology Guilin 541004 China Surfcontrol Pty Ltd Australia

Three-dimensional trajectory parameter measurement of industrial products is the key technical criteria that drives the product *** has recently become one of the hotspots in the measurement *** paper presents a method for measuring the eyeglass frame parameters using the inner trajectory as measurement *** three-dimensional parameters can be measured and calculated from top view and front *** preprocessing is performed to ensure the reliability of data *** necessary derivation and explanation for formulas of important parameters are provided.A standard square board is used as the template and is measured multi-times to verify the measurement *** experimental data are processed and the type A uncertainty is calculated,which concludes that the measurement results are convincible and comply with the product standard,and the proposed method is correct and the design requirements are met.

关键词：工业产品三维轨迹参数曲率镜片结构测量