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黄河河龙区间水情自动测报系统站网设计 被引量:2
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作者 刘晓伟 许卓首 +1 位作者 刘龙庆 李扬俊 《水资源与水工程学报》 2008年第1期64-68,共5页
分析了黄河河龙区间水情报汛站网现状,指出无论站网密度还是时效性,都不能满足黄河防汛及调水调沙、小北干流放淤试验等重大治黄实践对该区水文情报的需求,必须加快该区水情自动测报系统建设。结合该区暴雨洪水特点及黄河防汛、治黄实... 分析了黄河河龙区间水情报汛站网现状,指出无论站网密度还是时效性,都不能满足黄河防汛及调水调沙、小北干流放淤试验等重大治黄实践对该区水文情报的需求,必须加快该区水情自动测报系统建设。结合该区暴雨洪水特点及黄河防汛、治黄实践等方面的需求,对河龙区间水情自动测报系统站网进行了设计,并对其合理性进行了分析论证。 展开更多
关键词 水情报汛 站网设计 黄河河龙区间
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基于遗传算法和克里金的气温站网拓展设计 被引量:6
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作者 王佐鹏 张颖超 +2 位作者 熊雄 潘霄 陈昕 《科学技术与工程》 北大核心 2020年第12期4780-4786,共7页
利用江苏省2016年58个地面气象站日均温数据,针对其站点布局的不合理以及对未来站网的拓展,提出一种基于地统计克里金法和遗传算法的方法,以研究区域现有地面气温站点,利用克里金方法计算整个区域的克里金方差并对研究区域进行估值作为... 利用江苏省2016年58个地面气象站日均温数据,针对其站点布局的不合理以及对未来站网的拓展,提出一种基于地统计克里金法和遗传算法的方法,以研究区域现有地面气温站点,利用克里金方法计算整个区域的克里金方差并对研究区域进行估值作为模拟站点,通过遗传算法从模拟站点中寻找最优的站网组合,解决局部最优站点组合起来不一定是整体最优的问题。最终确定了6个添加站点位置,研究结果为未来气温站网的建设提供了理论参考。 展开更多
关键词 气温 克里金插值法 遗传算法 站网拓展设计
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珠江三角洲地区水文站网布设及水文测验的分析研究 被引量:6
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作者 姚章民 谢志强 沈鸿金 《水文》 CSCD 北大核心 2003年第5期20-23,27,共5页
水系复杂的珠江三角洲河网地区具有独特的水文站网布设及水文测验方法。在分析研究目前站网及测验存在的主要问题的同时,对今后的站网建设及测验工作提出了几点有益的建议,将为研究该区的水文规律和特性,为防汛抗旱、治理和开发提供科... 水系复杂的珠江三角洲河网地区具有独特的水文站网布设及水文测验方法。在分析研究目前站网及测验存在的主要问题的同时,对今后的站网建设及测验工作提出了几点有益的建议,将为研究该区的水文规律和特性,为防汛抗旱、治理和开发提供科学依据。 展开更多
关键词 水文站网 站网设计 水文测验 潮汐河流 珠江三角洲
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颖河流域水质动态监测站网的合理性分析
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作者 金立新 吴培任 《水资源保护》 CAS 1992年第2期26-32,共7页
本文首次将相对定量的方法分析了水质监测站网的设计,并将此方法运用于淮河流域上游的一个子流域颖河流域的水质动态监测站网的合理性分析。结合排污负荷应用流域形心的方法来确定水质监测站的宏观位置,应用统计方法来确定指定测站的采... 本文首次将相对定量的方法分析了水质监测站网的设计,并将此方法运用于淮河流域上游的一个子流域颖河流域的水质动态监测站网的合理性分析。结合排污负荷应用流域形心的方法来确定水质监测站的宏观位置,应用统计方法来确定指定测站的采样频率,对于优化设置站网和增加资料代表性的可靠程度是一种新的十分有效的尝试。本文还提出了颖河流域实际动态监测站网设置的改进意见。 展开更多
关键词 颖河流域 水质动态监测 站网设计 流域形心 排污负荷
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用平均相关系数法确定深圳雨量站网密度 被引量:1
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作者 魏进春 韩友平 马勤 《水利水电快报》 2001年第24期9-11,共3页
站网密度的确定是水文站网规划的关键。根据深圳市的降水特性和站网规划要求 ,以深圳市 14个雨量站的实测雨量资料为样本 ,结合地图量算的测站间距离 ,采用平均相关系数法 ,计算出各流域面积下的雨量站数目。计算结果和《水文站网规划... 站网密度的确定是水文站网规划的关键。根据深圳市的降水特性和站网规划要求 ,以深圳市 14个雨量站的实测雨量资料为样本 ,结合地图量算的测站间距离 ,采用平均相关系数法 ,计算出各流域面积下的雨量站数目。计算结果和《水文站网规划技术导则》推荐的雨量站网密度基本相同 ,说明用《水文站网规划技术导则》 展开更多
关键词 雨量站 站网设计 计算方法 深圳市 站网密度 平均相关系数法
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同朔区水文站网实施站队结合的必要性
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作者 王威 《山西水利科技》 1997年第1期68-71,共4页
同朔区有桑干河等五大主要河流,设有国家基本水文站10处,自50年代建站以来,一直采用单一的定点观测方式。随着国民经济建设的发展,人类活动对水文站网的影响日益加剧,现站网在区域控制性,代表性及水量控制功能等方面均存在着... 同朔区有桑干河等五大主要河流,设有国家基本水文站10处,自50年代建站以来,一直采用单一的定点观测方式。随着国民经济建设的发展,人类活动对水文站网的影响日益加剧,现站网在区域控制性,代表性及水量控制功能等方面均存在着较为突出的问题,单一的定点观测方式和管理体制,已极不适应社会发展的需要。从全国的经验看,解决这些问题的唯一出路是对水文基层管理体制及测验方式进行改革,实行水文勘测站队结合,即:建立站队结合基地,对各类水文观测站点实行统筹规划,按驻测、巡测、间测、调查、委托等方式分类观测,强化站网整体功能,扩大资料收集的深度和广度,进而利用人员相对集中的优势,结合生产需要进行水文资料深加工和开展水文科研,使水文工作转化为生产力。 展开更多
关键词 水文站网 站网设计 管理体制
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铁路BDS/GNSS高精度位置服务平台建设方案研究 被引量:7
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作者 武瑞宏 许双安 何金学 《测绘标准化》 2020年第3期27-31,共5页
铁路工程建设和运营管理迫切需要高精度位置服务,卫星导航定位基准站网技术为铁路高精度空间位置服务提供了新的解决方案。对铁路BDS/GNSS高精度位置服务平台建设方案进行研究,重点探讨平台构成、技术架构及网络RTK关键技术,对后续铁路... 铁路工程建设和运营管理迫切需要高精度位置服务,卫星导航定位基准站网技术为铁路高精度空间位置服务提供了新的解决方案。对铁路BDS/GNSS高精度位置服务平台建设方案进行研究,重点探讨平台构成、技术架构及网络RTK关键技术,对后续铁路工程GNSS基准站网的建设具有指导意义。 展开更多
关键词 位置服务平台 多需求位置服务 基准站网设计 基线解算 BDS/GNSS
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美国全国河流水质监测网简介
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作者 曹捍 崔巍 《环境科学动态》 1986年第2期22-24,共3页
水质监测网概况:美国地质调查局(USGS)上设两个全国性的水质监测网组织:国家水文基本站网和国家河流水质监测网.其中,水文基本站网由51个分布在较小流域上的水文站组成,这些小流域尽可能接近其自然状况。
关键词 河流水质 水质监测 美国地质调查局 水质资料 溶解有机碳 痕量元素 站网设计 主要水系 水环境 监测单元
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Simultaneous optimization of transit network and public bicycle station network 被引量:1
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作者 刘洋 朱宁 马寿峰 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第4期1574-1584,共11页
The traditional manner to design public transportation system is to sequentially design the transit network and public bicycle network. A new public transportation system design problem that simultaneously considers b... The traditional manner to design public transportation system is to sequentially design the transit network and public bicycle network. A new public transportation system design problem that simultaneously considers both bus network design and public bicycle network design is proposed. The chemical reaction optimization(CRO) is designed to solve the problem. A shortcoming of CRO is that, when the two-molecule collisions take place, the molecules are randomly picked from the container.Hence, we improve CRO by employing different mating strategies. The computational results confirm the benefits of the mating strategies. Numerical experiments are conducted on the Sioux-Falls network. A comparison with the traditional sequential modeling framework indicates that the proposed approach has a better performance and is more robust. The practical applicability of the approach is proved by employing a real size network. 展开更多
关键词 public transportation system transit route design bicycle sharing system chemical reaction optimization mating strategy
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Design and Description of a Photovoltaic Pumping System: Application in the Site of Adrar 被引量:1
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作者 Ahmed Mehdaoui Amar Hadj Arab Djaafar Seminar 《Journal of Environmental Science and Engineering(B)》 2012年第2期183-186,共4页
The Saharan areas and in particular the isolated sites are characterized by low levels of population, in dispersed cores, which suffer from serious problems of water supply for consumption and the irrigation. The phot... The Saharan areas and in particular the isolated sites are characterized by low levels of population, in dispersed cores, which suffer from serious problems of water supply for consumption and the irrigation. The photovoltaic pumping systems (PV) are an ideal solution for these problems. Despite the presence of several photovoltaic pumping systems (PVPS) projects, data acquisition system is still missing in most cases. In this work, the authors will present the PVPS installed at the unit of research in renewable energies in Saharan medium (URERMS, Algeria). This system will enable us to better analyze the performances ofa photovoltaic pumping system in Saharan medium. The principal elements of the chain of the photovoltaic pumping system are: a photovoltaic generator, the power conditioning system, a motor-driven pump immersed group, an electric wiring, a hydraulic infrastructure which comprises a water tank. 展开更多
关键词 Photovoltaic pumping DIMENSIONING optimization system of irrigation performances.
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Looking Back and Prospecting to the Project Design of the Spaceflight Launching Site in China
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作者 Zhang Zeming Chen Yujun 《Engineering Sciences》 EI 2008年第1期9-14,共6页
The development history of the project design of spaceflight launching site in China and the main forms used in these designs were introduced in this thesis, and it was pointed out that the spaceflight launch should n... The development history of the project design of spaceflight launching site in China and the main forms used in these designs were introduced in this thesis, and it was pointed out that the spaceflight launch should not use only one fixed model. According to its nation condition, China should design and build the launching project facility and device which correspond to the technology development of spacecraft and carrier rocket. 展开更多
关键词 launching site project design development history combination mode
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Design and Implementation of Verification Code Identification Based on Anisotropic Heat Kernel 被引量:2
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作者 LIU Lizhao LIU Jian +3 位作者 DAI Yaomei XU Huarong YIN Huayi ZHU Shunzhi 《China Communications》 SCIE CSCD 2016年第1期100-112,共13页
Many websites use verification codes to prevent users from using the machine automatically to register,login,malicious vote or irrigate but it brought great burden to the enterprises involved in internet marketing as ... Many websites use verification codes to prevent users from using the machine automatically to register,login,malicious vote or irrigate but it brought great burden to the enterprises involved in internet marketing as entering the verification code manually.Improving the verification code security system needs the identification method as the corresponding testing system.We propose an anisotropic heat kernel equation group which can generate a heat source scale space during the kernel evolution based on infinite heat source axiom,design a multi-step anisotropic verification code identification algorithm which includes core procedure of building anisotropic heat kernel,settingwave energy information parameters,combing outverification codccharacters and corresponding peripheral procedure of gray scaling,binarizing,denoising,normalizing,segmenting and identifying,give out the detail criterion and parameter set.Actual test show the anisotropic heat kernel identification algorithm can be used on many kinds of verification code including text characters,mathematical,Chinese,voice,3D,programming,video,advertising,it has a higher rate of 25%and 50%than neural network and context matching algorithm separately for Yahoo site,49%and 60%for Captcha site,20%and 52%for Baidu site,60%and 65%for 3DTakers site,40%,and 51%.for MDP site. 展开更多
关键词 verification code image recognition data mining scale space anisotropic heat kernel
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Evolution of Commercial Space near the Subway Stations of Community Type Based on Self-Organization Theory: A Case Study of Chengdu Wannianchang Subway Station
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作者 YU Yang TAN Xin QIAN Yuexi 《Journal of Landscape Research》 2018年第4期5-11,共7页
The subway stations of urban community type are not only main nodes in the urban traffic network, but also important places for peopled daily life. Widi the rapid development of urban metro and urban economy, the ... The subway stations of urban community type are not only main nodes in the urban traffic network, but also important places for peopled daily life. Widi the rapid development of urban metro and urban economy, the commercial space near tiie subway station has become the focus of urban planning and urban spatial development, and commercial self-oiganization pkys an important role in the development of commercial operations, commercial structures, and commercial scales, so how to make effective use of the inherent laws of the commercial space evolution, and further guide the rational development of community businesses needs more attention and research. This paper takes Chengdu Wannianchang Subway Station as an example to study the evolution stage, influencing factors, evolution characteristics and laws of the neatby commercial space. Moreover, suggestions were put forward such as coordinating competition and collaboration, optimizing space design and management, co-directional self-organization and heter-oiganizations, in order to provide a new reference for the healthy and ordedy development of the neighboring commefdal space near the subway stations of community type. 展开更多
关键词 SELF-ORGANIZATION Subway station of community type Commercial space Wannianchang
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Ground Motion and Site Effects on Performance-Based Design
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作者 Antonio Ferraro Salvatore Grasso Michele Maugeri 《Journal of Civil Engineering and Architecture》 2010年第7期34-41,共8页
The objective of Performance-Based Earthquake Engineering (PBEE) is the analysis of performance objectives with a specified annual probability of exceedance. Increasingly undesirable performance is caused by increas... The objective of Performance-Based Earthquake Engineering (PBEE) is the analysis of performance objectives with a specified annual probability of exceedance. Increasingly undesirable performance is caused by increasing levels of strong ground motion having decreasing annual probabilities of exceedance. The development of this methodology includes three steps: (1) evaluation of the distribution of ground motion at a site; (2) evaluation of the distribution of system response; (3) evaluation of the probability of exceeding decision variables within a given time period, given appropriate damage measures. The work has taken a systematic approach to determine the impact of increasing levels of detail in site characterization on the accuracy of ground motion and site effects predictions. Complementary studies have investigated the use of the following models for evaluating site effects: (1) amplification factors defined on the basis of generalized site categories, (2) one-dimensional ground response analysis, and (3) two-dimensional ground response analysis for surface topography on ground motion. The paper provides a brief synthesis of ground motion and site effects analysis procedures within a Performance-Based Design framework. It focuses about the influence on the evaluation of site effects in some active regions by different shear waves velocity measurements Down Hole (D-H), Cross Hole (C-H), Seismic Dilatometer Marchetti Test (SDMT) and by different variation of shear modulus and damping ratio with strain level and depth from different laboratory dynamic tests for soil characterization: Resonant Column Test (RCT), Cyclic Loading Torsional Shear Test (CLTST). 展开更多
关键词 Site effects Performance Based Design (PBD) ground motion soil non-linearity seismic response analysis
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Research on Website Construction of Quality Course based on Network Teaching Platform
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作者 Rong Rong 《International Journal of Technology Management》 2013年第1期89-92,共4页
through the teaching design of online course quality and application practice, the instructional design process based on B/S learning are analyzed, and discusses several key problems in the design and teaching. The pr... through the teaching design of online course quality and application practice, the instructional design process based on B/S learning are analyzed, and discusses several key problems in the design and teaching. The proposed resource-based learning teaching design network course should adapt to the application mode of network teaching and traditional classroom combination; will provide teaching demonstration, teaching content self testing evaluation for students, and to provide jobs for teachers management, online Q & A, BBS, database and knowledge construction and other functions, greatly improving the efficiency of teaching "excellent course" . 展开更多
关键词 ASP technology B/S structure system quality course
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An easy-to-use site-directed mutagenesis method with a designed restriction site for convenient and reliable mutant screening 被引量:4
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作者 Bao-zhong ZHANG Xin ZHANG +4 位作者 Xiao-ping AN Duo-liang RAN Yu-sen ZHOU Jun LU Yi-gang TONG 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2009年第6期479-482,共4页
Site-directed mutagenesis (SDM) has been a very important method to probe the function-structure relationship of proteins. In this study, we introduced an easy-to-use, polymerase chain reaction (PCR)-based SDM method ... Site-directed mutagenesis (SDM) has been a very important method to probe the function-structure relationship of proteins. In this study, we introduced an easy-to-use, polymerase chain reaction (PCR)-based SDM method for double-stranded plasmid DNA, with a designed restriction site to ensure simple and efficient mutant screening. The DNA sequence to be mutated was first translated into amino acid sequence and then the amino acid sequence was reversely translated into DNA sequence with degenerate codons, resulting in a large number of sequences with silent mutations, which contained various restriction endonu-clease (RE) sites. Certain mutated sequence with an appropriate RE site was selected as the target DNA sequence for designing a pair of mutation primers to amplify the full-length plasmid via inverse PCR. The amplified product was 5′-phosphorylated, cir-cularized, and transformed into an Escherichia coli host. The transformants were screened by digesting with the designed RE. This protocol uses only one pair of primers and only one PCR is conducted, without the need for hybridization with hazardous isotope for mutant screening or subcloning step. 展开更多
关键词 Site-directed mutagenesis (SDM) Restriction endonuclease Mutant screening
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