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Taxonomic status of Chinese blue sheep(Pseudois nayaur):new evidence of a distinct subspecies

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Integrative Zoology 2020年第3期15卷 202-212页

作者： Hui GAO Nannan li Yongjie HUANG Fujie QIAO Junle li zongzhi li Yanxiang li Zhenghuan WANG liwei TENG Zhensheng liU College of Wildlife and Protected Area Northeast Forestry UniversityHarbinChina Forestry Science and Technology Research Institute of Greater Hinggan in Inner Mongolia YakeshiChina School of Ecology and Nature Conservation Beijing Forestry UniversityBeijingChina School of life Sciences Lvliang UniviersityLvliangChina School of life Sciences East China Normal UniversityShanghaiChina Key Laboratory of Conservation Biology National Forestry and Grassland AdministrationHarbinChina

The blue sheep is an endemic species to the Qinghai-Tibet Plateau and surrounding *** has been regarded as having 2 subspecies:Pseudois nayaur nayaur and ***,such a classification remains ***,we analyze 10 microsatellite loci and part of the mitochondrial control region for clarification in such taxonomic *** use samples from 168 individuals from 6 geographic populations covering almost all the distribution areas of the species in China to carry out *** trees derived from both the microsatellite and mitochondrial markers combined with the discriminant analysis of principal components(DAPC)and the STRUCTURE analysis reveal that the individuals in the Helan Mountains are well grouped with a distinct evolutionary lineage and are significantly different from the other populations of *** according to Fst values,implying that this isolated population should be categorized as a valid subspecies;namely,Pseudois nayaur *** isolation-by-distance(IBD)analysis shows a significant positive relationship between genetic and geographical distances among the populations.

关键词： blue sheep isolation by distance microsatellite mtDNA control region taxonomy

Application for Spare Parts Inventory Strategy with Aircraft Perfect Rate

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Journal of Systems Science and Information 2007年第2期5卷 103-108页

作者： Xingfang Fu zongzhi li College of Humanities and Social Sciences Nanjing University of Aeronautics and Astronautics Nanjing 210016 China Department of Spare Parts Management Xuzhou Air Force Institute Xuzhou 221000 China

Traditional ratio like expected backorder （EBO） ascertaining the inventory strategy of spare parts in practical applications, only eyes on the spare parts inventory system itself, and ignores, the effect of the system information on aircraft or other spaxe parts. In this paper, we introduce the ratio of Aircraft perfect rate, it is a synthesis index to reflect the whole aircraft status, and can deal with spare parts inventory system, concerning not only EBO of spare parts, but also the influence of it on aircraft and other spare parts possibly. We provide the process of calculation that demonstrate how to buy spare parts in case of the maintenance power of aircraft, and have got a clear inventory strategy of spare parts, its easy implementation is illustrated in a case study.

关键词： aircraft perfect rate inventory strategy spare parts management

Safety impacts of red light running photo enforcement at urban signalized intersections

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Journal of Traffic and Transportation Engineering(English Edition) 2014年第5期1卷 309-324页

作者： Yongdoo Lee zongzhi li Shengrui Zhang Arash M.Roshandeh Harshingar Patel Yi liu Department of Civil Architectural and Environmental EngineeringIllinois Institute of Technology School of Highway Chang’an University School of Civil Engineering Purdue University

Red light running at signalized intersections is a major safety concern in the United States. Statistics show that approximately 45 percent of crashes at intersections caused by red light running re- sult in severe injuries and fatalities, while only approximately 30 percent of all other types of intersec- tion crashes cause injuries or fatalities. Over the past decade, many US cities and counties have de- ployed red light running photo enforcement systems for signalized intersections within their jurisdictions to potentially reduce red light running related crashes. This study proposes an empirical Bayesian （ EB ） before-after analysis method that computes a weighed sum of crashes observed in the field and crashes predicted by safety performance functions （SPFs） to mitigate regression-to-mean biases for analyzing crash reduction effects of red light running enforcement. The analysis explicitly considers red light run- ning related crash types, including head-on, rear-end, angle, tuming, sideswipe in the same direction, and sideswipe in the opposite direction; and crash severity levels classified as fatal, injury, and proper- ty damage only （PDO）. A computational study is conducted to examine the effectiveness of the Chica- go program with red light running photo enforcement systems deployed for nearly two hundred signal- ized intersections. It is revealed that the use of red light running photo enforcement on the whole is pos- itive, as demonstrated by reductions in all types of fatal crashes by 4-48 percent, and injury-related an- gle crashes by 1 percent. However, it slightly raises PDO-related angle crashes and moderately increa- ses injury and PDO related rear-end crashes. The safety effectiveness of red light running photo en- forcement is sensitive to intersection location.

关键词： signalized intersection red light running safety impact empirical bayesian method

Vehicle and pedestrian safety impacts of signal timing optimization in a dense urban street network

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Journal of Traffic and Transportation Engineering(English Edition) 2016年第1期3卷 16-27页

作者： Arash M.Roshandeh zongzhi li Shengrui Zhang Herbert S.Leuinson Xi Lu Department of Engineering and Public Works City of AlpharettaGA 30009USA Department of civil Architectural and Environmental Engineeringillinois Institute of TechnologyChicagoIL 60616USA School of Highway Chang'an UniuersityXi'an 710064China Herbert S.Leuinson Transportation Consultant New HauenCT 06492USA

Intersection signal timing optimization is expected to affect both traffic mobility and safety. However, in safety impacts analysis, the existing studies mainly focus on estimating changes in vehicle crashes without addressing the influence of pedestrian related crashes. This study aims to simultaneously assess the overall impacts of vehicle and pedestrian crashes caused by signal timing optimization in dense urban street networks. An empirical Bayesian analysis method was introduced to estimate the safety impacts of intersection signal timing optimization in an urban street network in terms of vehicle-tovehicle and vehicle-to-pedestrian crashes at intersections, as well as single and multiple vehicle crashes on street segments. A computational experiment was performed to apply the proposed method to the Chicago central business district that includes 875 signalized intersections and 2016 roadway segments. Results show that vehicle-to-vehicle and vehicle-to-pedestrian crashes at intersections are decreased in different crash severity levels and types, especially for angle and rear-end ones after signal timing optimization. Similar results are found for multi-vehicle rear-end crashes on street segments. These indicate that intersection signal timing optimization in dense urban street networks has a potential for improving traffic mobility, vehicle and pedestrian safety at intersections, and vehicle safety on street segments.

关键词： SignalOptimizationSafetyVehiclePedestrianEmpirical Bayesian analysis

Magnetic properties and tunneling magnetoresistance in FeCo-SiO_2 granular films

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Chinese Science Bulletin 2001年第9期46卷 734-737页

作者： XI li, ZHANG zongzhi, CHI Junhong, li Chengxian & GE ShihuiKey Laboratory for Magnetism and Magnetic Materials of the Ministry of Education, Lanzhou University, Lanzhou 730000, China Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education Lanzhou University Lanzhou China

Fefv(SiO2)1-fv granular films were fabricated by rf sputtering (fv represents the Fe volume fraction). The mi-crostructure, magnetic properties as well as the tunneling magnetoresistance effect (TMR) were systematically studied. It was found that the maximum TMR ratio is about -3.3% at fv = 0.33. Under the same condition, a series of (Fe100-x Cox)0.33(SiO2)0.67 were prepared. TMR value reaches -4.5% at x=53, while the microstructure of the film still keeps as that of Fe0.33(SiO2)0.67. The higher TMR ratio is contributed to the elevating of the spin polarization of particles. This is consistent with Inoue’s theory.

关键词： tunneling magnetoresistance granular films.

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基于产业集聚的高技术产业创新能力研究

科研管理 2011年第1期32卷 15-21,28页

作者：周明李宗植东华理工大学经济与管理学院江西抚州344000 南京航空航天大学经济与管理学院江苏南京210016

对经典的知识生产函数进行改进的基础上,构建了综合考虑研发经费和知识存量的知识生产函数,并将高技术产业集聚下知识溢出因素和政府支持力度引入该函数,以1998—2006年中国高技术产业相关统计数据,利用空间面板模型分析方法,从产业集... 详细信息

对经典的知识生产函数进行改进的基础上,构建了综合考虑研发经费和知识存量的知识生产函数,并将高技术产业集聚下知识溢出因素和政府支持力度引入该函数,以1998—2006年中国高技术产业相关统计数据,利用空间面板模型分析方法,从产业集聚的视角对区域高技术产业技术创新能力进行了实证分析,分析结果表明:考虑了研发经费和知识存量的知识生产函数能够比较准确地揭示高技术产业知识生产的投入产出关系,省域内的产业集聚因素和省际间的知识溢出显著影响区域高技术产业的创新产出。

关键词：创新能力技术生产函数产业集聚空间面板

人口、经济和技术对二氧化碳排放的影响分析——基于动态面板模型

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人口研究 2010年第3期34卷 32-39页

作者：李国志李宗植南京航空航天大学经管学院江西农业大学南昌商学院

气候变化和二氧化碳减排问题已经引起了世界性的关注。一般而言,一个国家的二氧化碳排放量是由多种因素共同作用决定的,并且这些因素对碳排放量的作用可能有所不同。文章基于动态面板模型,利用中国30个省份的相关数据,分析了二氧化碳排... 详细信息

气候变化和二氧化碳减排问题已经引起了世界性的关注。一般而言,一个国家的二氧化碳排放量是由多种因素共同作用决定的,并且这些因素对碳排放量的作用可能有所不同。文章基于动态面板模型,利用中国30个省份的相关数据,分析了二氧化碳排放与人口、经济、技术的关系。结果表明,人口、经济和技术对不同地区二氧化碳排放的影响是不一样的。其中人口对二氧化碳排放的影响呈现明显的双向性,经济增长对碳排放具有较强的促进作用,而技术进步则在一定程度上缓解了二氧化碳排放。另外,二氧化碳排放表现出明显的路径依赖现象,当期经济增长将至少对未来1~3年的空气质量产生影响。基于上述结论,文章提出了减少二氧化碳排放的相关政策建议,以适应中国的低碳经济道路。

关键词：二氧化碳排放动态面板模型路径依赖