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National 2000' GPS control network of china

Progress in Natural Science:Materials International 2007年第8期17卷 983-987页

作者： Yang Yuanxi~(1**) Tang Yingzhe~1 Chen Chuanlu~2 Wang Min~3 Zhang Peng~4.Wang Xiaorui~2 Song Lijie~5 Zhang Zusheng~6 (1.Xi'an Research Institute of Surveying and Mapping,Xi'an 710054.china 2.Geodetic Data Processing Center,Xi'an 710054.china 3.Center of Earthquake Analysis and Prediction,china Seismological Bureau,Beijing 100036,china 4.National Geomatics Center of china,Beijing 10004.,china 5.Institute of Surveying and Mapping,zhengzhou University of Information Engineering,zhengzhou 4.0052,china 6.First Crustal Deformation Monitoring Center,china Seismological Bureau,Tianjin 300180,china) Xi'' an Research Institute of Surveying and Mapping Xi'' an 710054 China Geodetic Data Processing Center Xi'' an 710054 China Center of Earthquake Analysis and Prediction China Seismological Bureau Beijing 100036 China National Geomatics Center of china Beijing 100044 China Institute of Surveying and Mapping Zhengzhou University of Information Engineering Zhengzhou 450052 China First Crustal Deformation Monitoring Center China Seismological Bureau Tianjin 300180 China

An accurately unified national GPS network with more than 2500 stations,named"National 2000' GPS Control Net- work",signed the epoch 2000.0,has been established by integrating the existing six nationwide GPS networks of china set up by differ- ent departments with different *** paper presents the characteristics of the existing GPS networks,summarizes the strategies in the integrated adjustment of the GPS network,including functional model,stochastic model as well as the adjustment principle modifi- *** modifying the adjustment strategies according to the characteristics of the existing GPS networks and under the support of the IGS stations,the accuracy of the integrated national GPS network is greatly *** datum differences among the sub networks disappear,the systematic error influences are weakened,and the effects of the outliers on the estimated coordinates and their variances are *** is shown that the average standard deviation for the horizontal component is smaller than 1.0 cm,the vertical component is smaller than 2.0 cm,and the three-dimensional (3-D) position of geocenter coordinates is smaller than 3.0 *** exterior checking ac- curacy for the 3-D position is averagely better than 1.0 cm.

关键词： GPS control network adjustment systematic errors robust estimation variance component estimation coordinate system

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Effect of Initial Microstructure on Warm Deformation Behavior of 4. Steel

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Journal of Iron and Steel Research International 2012年第8期19卷 75-78页

作者： ZHAO Xin1, YANG Xiao-ling2, JING Tian-fu3 (1. The Sixth Department, zhengzhou Institute of Aeronautics, zhengzhou 4.0015, Henan, china 2. zhengzhou Zhongxing Basic Constructions Development Co Ltd, zhengzhou 4.0015, Henan, china 3. State Key Laboratory of Metastable Materials Science and Technology, Qinhuangdao 066004. Hebei, china) The Sixth Department Zhengzhou Institute of Aeronautics Zhengzhou Henan China zhengzhou Zhongxing Basic Constructions Development Co Ltd Zhengzhou Henan China State Key Laboratory of Metastable Materials Science and Technology Qinhuangdao Hebei China

In order to investigate the effect of initial microstructure on warm deformation behavior, some specimens of 4. steel were annealed and some quenched. Then the specimens were isothermally compressed on a Gleeble 3500 machine. The deformation temperature range was 550 to 700 ℃ and the strain rate range was 0.001 to 0.1 s-1. An optical microscope (OM) and a transmission electron microscope (TEM) were used to study the microstructures. The results show that the microstructure of annealed specimens is ferrite and pearlite and that of quenched specimens is martensite. The flow stress of quenched specimens is higher than that of annealed ones at 550 ℃ when strain rates are greater than 0.001 s-1. However, at 600 to 700 ℃ and strain rate of 0.001 s-1, the whole flow curves of quenched specimens are below that of annealed ones. Under the rest conditions, the flow stress of quenched specimens is higher at the beginning of compression and then the opposite is true after the strain is greater than a critical value. The microstructure examination proves that the tempering and dynamic recrystallization easily occur in the specimens with martensite during warm compression, which results in the above phenomena.

关键词： warm deformation flow stress steel microstructure

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EVOLUTIONAL CHARACTERISTICS OF HYPER－CONCENTRATED FLOW IN BRAIDED CHANNEL OF THE YELLOW RIVER

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International Journal of Sediment Research 1996年第3期 49-57页

作者： QI Pu LI Wenxue( Institute of Hydraulic Research,Yellow River Conservancy Commission,zhengzhou 450003.P.R.china)( Chief Engineer,Yellow River Conservancy Commission,zhengzhou 450003.P.R.china)

ＥＶＯＬＵＴＩＯＮＡＬＣＨＡＲＡＣＴＥＲＩＳＴＩＣＳＯＦＨＹＰＥＲ－ＣＯＮＣＥＮＴＲＡＴＥＤＦＬＯＷＩＮＢＲＡＩＤＥＤＣＨＡＮＮＥＬＯＦＴＨＥＹＥＬＬＯＷＲＩＶＥＲ￥ＱＩＰｕ；ＬＩＷｅｎｘｕｅ（Ｓｅｎｉｏｒｅｎｇｉｎ... 详细信息

ＥＶＯＬＵＴＩＯＮＡＬＣＨＡＲＡＣＴＥＲＩＳＴＩＣＳＯＦＨＹＰＥＲ－ＣＯＮＣＥＮＴＲＡＴＥＤＦＬＯＷＩＮＢＲＡＩＤＥＤＣＨＡＮＮＥＬＯＦＴＨＥＹＥＬＬＯＷＲＩＶＥＲ￥ＱＩＰｕ；ＬＩＷｅｎｘｕｅ（Ｓｅｎｉｏｒｅｎｇｉｎｅｅｒ，ＩｎｓｔｉｔｕｔｅｏｆＨｙ...

关键词： Hyper-concentrated flood Channel Braided river Hydrograph Sediment concentration Peak flow Flood stage Channel shape

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Association of physical activity with risk of chronic kidney disease in china:A population-based cohort study

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Journal of Sport and Health Science 2024年第2期13卷 204-211页

作者： Kexiang Shi Yunqing Zhu Jun Lv Dianjianyi Sun Pei Pei Huaidong Du Yiping Chen Ling Yang Bing Han Rebecca Stevens Junshi Chen Zhengming Chen Liming Li Canqing Yu china Kadoorie Biobank collaborative group Department of Epidemiology&Biostatistics School of Public HealthPeking University Health Science CenterBeijing 100191China Peking University Center for Public Health and Epidemic Preparedness&Response Beijing 100191China Key Laboratory of Epidemiology of Major Diseases(Peking University) Ministry of EducationBeijing 100191China Clinical Trial Service Unit&Epidemiological Studies Unit(CTSU) Nuffield Department of Population HealthUniversity of OxfordOxford OX37LFUK Medical Research Council Population Health Research Unit at the University of Oxford Oxford OX37LFUK NCDs Prevention and Control Department Henan Center for Disease Control and PreventionZhengzhou 450016China china National Center for Food Safety Risk Assessment Beijing 100022China 不详

Background:Information on the association between physical activity(PA)and the risk of chronic kidney disease(CKD)is *** aimed to explore the associations of total,domain-specific,and intensity-specific PA with CKD and its subtypes in ***:The study included 4.5,376 adults from the china Kadoorie Biobank aged 30-79 years during 2004.2008 at *** interviewer-administered questionnaire was used to collect the information about PA,which was quantified as metabolic equivalent of task hours per day(MET-h/day)and categorized into 4.groups based on *** regression was used to analyze the association between PA and CKD ***:During a median follow-up of 12.1 years,54.5 incident CKD cases were documented,including 1159 incident diabetic kidney disease(DKD)cases and 362 incident hypertensive nephropathy(HTN)*** PA was inversely associated with CKD risk,with an adjusted hazard ratio(HR,95%confidence interval(95%CI))of 0.83(0.75-0.92)for incident CKD in the highest quartile of total PA as compared with participants in the lowest *** results were observed for risk of DKD and HTN,and the corresponding HRs(95%CIs)were 0.75(0.58-0.97)for DKD risk and 0.56(0.37-0.85)for HTN *** nonoccupational PA,low-intensity PA,and moderate-to-vigorous-intensity PA were significantly associated with a decreased risk of CKD,with HRs(95%CIs)of 0.80(0.73-0.88),0.85(0.77-0.94.,and 0.85(0.76-0.95)in the highest quartile,***:PA,including nonoccupational PA,low-intensity PA,and moderate-to-vigorous-intensity PA,was inversely associated with the risk of CKD,including DKD,HTN,and other CKD,and such associations were dose dependent.

关键词： Chronic kidney disease Domain Intensity Physical activity

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Evaluation of Interfacial Adhesion Property for Thin Hard Films with Fuzzy Method

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Journal of Wuhan University of Technology(Materials Science) 2010年第5期25卷 829-831页

作者：朱强 School of Mechanical Engineering Zhengzhou University

According to nanoscratch results for the TiN film, an evaluation method for interfacial fracture toughness of thin hard films is presented with fuzzy concepts, which can account for such influential factors in scratch test as surface roughness and material imperfection. Based on configuration changes in scratching curves, the parameters RV and RF are defined as the relative ratios of tip vertical displacement and of friction coefficinet. Fuzzy features of the scratching curves are analyzed carefully. The critical load is deduced from fuzzy logic operations and used to calculate the value of interfacial fracture toughness. With this method, the interfacial fracture toughness of TiN/HSS is evaluated approximately as 4.18 MPam^1/2. Results show that the method is valid and can benefit the interfacial adhesion property investigation for thin hard films.

关键词： interfacial adhesion thin hard films critical load fuzzy evaluation

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An Access Selection Functional Architecture for Heterogeneous Multi-Mode Terminals

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ZTE Communications 2008年第3期 50-53页

作者： Li Jun(Network Management Center,china Mobile Group Henan Co.,LTD,zhengzhou 450003.china)

The convergence of heterogeneous wireless networks is an inevitable trend in broadband wireless communications development. In heterogeneous networks convergence environment, each wireless network can provide ubiquitous, best Quality of Service (QoS) services. The challenge lies in the design of the management system and access selection architecture for heterogeneous multi-mode terminals. A type of management architecture for heterogeneous multi-mode terminal via effective interaction with all protocol layers is adaptable for multi-access standards and technical requirements to achieve seamless access and mobility for multi-mode heterogeneous terminals. As the core subject for research, access selection functional architecture mainly consists of three modules, namely access adaptation, mobility management, and user preference.

关键词： Access An Access Selection Functional Architecture for Heterogeneous Multi-Mode Terminals mode

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基于跨越连接与融合注意力机制的红外弱小目标检测方法

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光子学报 2024年第9期53卷 218-229页

作者：李慧李正周杨雨昕郝聪宇刘海涛重庆大学微电子与通信工程学院重庆401331

针对复杂背景红外小弱目标信号弱、特征不明显、干扰虚警多等检测性能低问题,提出基于跨越连接与融合注意力机制的单阶段红外弱小目标检测算法。该方法融合注意力机制与残差网络提取小目标多特征,减少复杂背景干扰;双向跨越连接结构融... 详细信息

针对复杂背景红外小弱目标信号弱、特征不明显、干扰虚警多等检测性能低问题,提出基于跨越连接与融合注意力机制的单阶段红外弱小目标检测算法。该方法融合注意力机制与残差网络提取小目标多特征,减少复杂背景干扰;双向跨越连接结构融合低层与高层各自的特征信息,凸显小弱目标特征表达能力;增加一个高分辨率检测层,重新聚类弱小目标先验框,增强目标与背景的特征差别学习能力;最后,建立真实目标和预测目标框的高斯分布模型,计算两者相似性,解决因IoU度量造成的目标损失回归偏差敏感问题,提升损失回归准确性。在公开红外小目标数据集上进行对比测试,实验结果表明该算法对多种复杂背景下红外小弱目标检测均取得了最佳性能,在平均精度和速度等方面都得到显著提升,模型最小,方便部署。

关键词：红外小目标目标检测跨越连接注意力机制多尺度融合

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LONG AND DEEP DIVERSION TUNNELS OF 1^(ST) STAGE PROJECT IN WEST ROUTE OF SOUTH-NORTH WATER TRANSFER PROJECT

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岩石力学与工程学报 2003年第9期22卷 1527-1532页

作者： Shen Fengsheng,Liu Xin (Reconnaissance,Planning,Design and Research Institute,Yellow River Construction Commission, Ministry of Water Resources, zhengzhou 450003.china) Reconnaissance Planning Design and Research Institute Yellow River Construction Commission Ministry of Water Resources Zhengzhou 450003

West Route of South-North Water Transfer Project,situated in southeastern Qinghai-Tibet Plateau,is a giant project,which will deliver 17 billion m3 of water from the main stream and tributaries upstream of the Yangtze River to the upper reaches of the Yellow River. It is to be constructed in 3 stages, of which the 1st stage project includes delivering 4.billion m3 of water by gravity from two tributaries of Yalong River and three tributaries of Dadu River. The project consists of 5 dams,7 tunnels and a channel in series,with the dam height of 63～123 m and water transfer length of 260.3 km,of which the tunnels measure 24..1 km. The special climatic,environmental and geologic conditions make the project much more complicated in construction,especially 3 tunnels with the length longer than 50 km each create challenges to the technical requirements of engineering survey,design and construction.

关键词：南水北调工程西线工程引水隧洞 TBM

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An Analysis of Suburban Agricultural Land Allocation System and Sustainable Development Strategy──Taking Kaifeng Suburban as an example

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Journal of Systems Science and Systems Engineering 2001年第4期13卷 409-417页

作者： QIN Ming-zhou1, ZHAO Shu-mao2 1. College of Environment and Planning, Henan University, Kadeng 4.5001, china 2. Planning Council of Henan Province, zhengzhou 450003. china College of Environment and Planning Henan UniversityKaifeng 475001 China Planning Council of Henan Province Zhengzhou 450003 China

Based on the system theory, this paper discusses the structure and efficiency of agricuItural land use in Kaifeng Suburban. Such present problems as benefit deviation from resource al1ocation, distinguished unemployment and four kinds of contribution of urban agriculture land use are revealed. Then, in the view of sustainab1e development, some resolution measures to the problems are advanced out. These suggestions include farmland protection, ecological agriculture, sustainable land use and input decrease of synthetic matter.

关键词： suburban agricultural land use resources allocation use efficiency farmland protection ecological agriculture

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Fracture analysis of a functionally graded interfacial zone between two dissimilar homogeneous materials

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Science china(Physics,Mechanics & Astronomy) 2006年第5期49卷 540-552页

作者： CHENG Zhanqi1,2 & ZHONG Zheng1 1. School of Aerospace Engineering and Applied mechanics, Tongji University, Shanghai 200092, china 2. College of Civil Engineering, zhengzhou University, zhengzhou 4.0002, china School of Aerospace Engineering and Applied mechanics Tongji University Shanghai China College of Civil Engineering Zhengzhou University Zhengzhou China

In this paper the plane elasticity problem for a functionally graded interfacial zone containing a crack between two dissimilar homogeneous materials has been considered. It is assumed that in the interfacial zone the reciprocal of the shear modulus is a linear function of the coordinate, while Possion’s ratio keeps constant. By utilizing the Fourier transformation technique and the transfer matrix method, the mixed boundary problem is reduced to a system of singular integral equations that are solved numerically. The influences of the geometric parameters and the graded parameter on the stress intensity factors are investigated. The numerical results show that the graded parameters, the thickness of interfacial zone, the crack size and location have significant effects on the stress intensity factors.

关键词： functionally graded material interfacial zone fracture stress intensity factor

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