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History and evaluation of national-scale geochemical data sets for the United States 被引量:8
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作者 David B.Smith Steven M.Smith John D.Horton 《Geoscience Frontiers》 SCIE CAS CSCD 2013年第2期167-183,共17页
Six national-scale,or near national-scale,geochemical data sets for soils or stream sediments exist for the United States.The earliest of these,here termed the 'Shacklette' data set,was generated by a U.S. Geologica... Six national-scale,or near national-scale,geochemical data sets for soils or stream sediments exist for the United States.The earliest of these,here termed the 'Shacklette' data set,was generated by a U.S. Geological Survey(USGS) project conducted from 1961 to 1975.This project used soil collected from a depth of about 20 cm as the sampling medium at 1323 sites throughout the conterminous U.S.The National Uranium Resource Evaluation Hydrogeochemical and Stream Sediment Reconnaissance(NUREHSSR) Program of the U.S.Department of Energy was conducted from 1975 to 1984 and collected either stream sediments,lake sediments,or soils at more than 378,000 sites in both the conterminous U.S.and Alaska.The sampled area represented about 65%of the nation.The Natural Resources Conservation Service(NRCS),from 1978 to 1982,collected samples from multiple soil horizons at sites within the major crop-growing regions of the conterminous U.S.This data set contains analyses of more than 3000 samples.The National Geochemical Survey,a USGS project conducted from 1997 to 2009,used a subset of the NURE-HSSR archival samples as its starting point and then collected primarily stream sediments, with occasional soils,in the parts of the U.S.not covered by the NURE-HSSR Program.This data set contains chemical analyses for more than 70,000 samples.The USGS,in collaboration with the Mexican Geological Survey and the Geological Survey of Canada,initiated soil sampling for the North American Soil Geochemical Landscapes Project in 2007.Sampling of three horizons or depths at more than 4800 sites in the U.S.was completed in 2010,and chemical analyses are currently ongoing.The NRCS initiated a project in the 1990s to analyze the various soil horizons from selected pedons throughout the U.S.This data set currently contains data from more than 1400 sites.This paper(1) discusses each data set in terms of its purpose,sample collection protocols,and analytical methods;and(2) evaluates each data set in terms of its appropriateness as a national-scale geochemical database and its usefulness for nationalscale geochemical mapping. 展开更多
关键词 Geochemical mapping National-scale geochemical data Geochemical baselines united States
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Fuzzy data envelopment analysis approach based on sample decision making units 被引量:11
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作者 Muren Zhanxin Ma Wei Cui 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第3期399-407,共9页
The conventional data envelopment analysis (DEA) measures the relative efficiencies of a set of decision making units with exact values of inputs and outputs. In real-world prob- lems, however, inputs and outputs ty... The conventional data envelopment analysis (DEA) measures the relative efficiencies of a set of decision making units with exact values of inputs and outputs. In real-world prob- lems, however, inputs and outputs typically have some levels of fuzziness. To analyze a decision making unit (DMU) with fuzzy input/output data, previous studies provided the fuzzy DEA model and proposed an associated evaluating approach. Nonetheless, numerous deficiencies must still be improved, including the α- cut approaches, types of fuzzy numbers, and ranking techniques. Moreover, a fuzzy sample DMU still cannot be evaluated for the Fuzzy DEA model. Therefore, this paper proposes a fuzzy DEA model based on sample decision making unit (FSDEA). Five eval- uation approaches and the related algorithm and ranking methods are provided to test the fuzzy sample DMU of the FSDEA model. A numerical experiment is used to demonstrate and compare the results with those obtained using alternative approaches. 展开更多
关键词 fuzzy mathematical programming sample decision making unit fuzzy data envelopment analysis EFFICIENCY α-cut.
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Reconfigurable-System-on-Chip Implementation of Data Processing Units for Space Applications
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作者 张宇宁 常亮 +1 位作者 杨根庆 李华旺 《Transactions of Tianjin University》 EI CAS 2010年第4期270-274,共5页
Application-specific data processing units (DPUs) are commonly adopted for operational control and data processing in space missions. To overcome the limitations of traditional radiation-hardened or fully commercial d... Application-specific data processing units (DPUs) are commonly adopted for operational control and data processing in space missions. To overcome the limitations of traditional radiation-hardened or fully commercial design approaches, a reconfigurable-system-on-chip (RSoC) solution based on state-of-the-art FPGA is introduced. The flexibility and reliability of this approach are outlined, and the requirements for an enhanced RSoC design with in-flight reconfigurability for space applications are presented. This design has been demonstrated as an on-board computer prototype, providing an in-flight reconfigurable DPU design approach using integrated hardwired processors. 展开更多
关键词 RSoC in-flight reconfigurability spaceborne data processing unit
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The Design and Implementation of the Data Buffer Unit in an Artificial intelligence Computer ITM-1
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作者 张晨曦 《High Technology Letters》 EI CAS 1996年第2期55-58,共4页
This paper describes the function,structure and working status of the data buffer unitDBU,one of the most important functional units on ITM-1.It also discusses DBU’s supportto the multiprocessor system and Prolog lan... This paper describes the function,structure and working status of the data buffer unitDBU,one of the most important functional units on ITM-1.It also discusses DBU’s supportto the multiprocessor system and Prolog language. 展开更多
关键词 DBU The Design and Implementation of the data Buffer unit in an Artificial intelligence Computer ITM-1 Prolog CPU ITM
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基于re3data的中英科学数据仓储平台对比研究 被引量:1
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作者 袁烨 陈媛媛 《数字图书馆论坛》 CSSCI 2024年第2期13-23,共11页
以re3data为数据获取源,选取中英两国406个科学数据仓储为研究对象,从分布特征、责任类型、仓储许可、技术标准及质量标准等5个方面、11个指标对两国科学数据仓储的建设情况进行对比分析,试图为我国数据仓储的可持续发展提出建议:广泛... 以re3data为数据获取源,选取中英两国406个科学数据仓储为研究对象,从分布特征、责任类型、仓储许可、技术标准及质量标准等5个方面、11个指标对两国科学数据仓储的建设情况进行对比分析,试图为我国数据仓储的可持续发展提出建议:广泛联结国内外异质机构,推进多学科领域的交流与合作,有效扩充仓储许可权限与类型,优化技术标准的应用现况,提高元数据使用的灵活性。 展开更多
关键词 科学数据 数据仓储平台 re3data 中国 英国
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Using Genetic Algorithm as Test Data Generator for Stored PL/SQL Program Units 被引量:1
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作者 Mohammad A. Alshraideh Basel A. Mahafzah +1 位作者 Hamzeh S. Eyal Salman Imad Salah 《Journal of Software Engineering and Applications》 2013年第2期65-73,共9页
PL/SQL is the most common language for ORACLE database application. It allows the developer to create stored program units (Procedures, Functions, and Packages) to improve software reusability and hide the complexity ... PL/SQL is the most common language for ORACLE database application. It allows the developer to create stored program units (Procedures, Functions, and Packages) to improve software reusability and hide the complexity of the execution of a specific operation behind a name. Also, it acts as an interface between SQL database and DEVELOPER. Therefore, it is important to test these modules that consist of procedures and functions. In this paper, a new genetic algorithm (GA), as search technique, is used in order to find the required test data according to branch criteria to test stored PL/SQL program units. The experimental results show that this was not fully achieved, such that the test target in some branches is not reached and the coverage percentage is 98%. A problem rises when target branch is depending on data retrieved from tables;in this case, GA is not able to generate test cases for this branch. 展开更多
关键词 GENETIC Algorithms SQL Stored PROGRAM unitS Test data Structural Testing SQL EXCEPTIONS
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An Integrated Method of Data Mining and Flow Unit Identification for Typical Low Permeability Reservoir Prediction
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作者 Peng Yu 《World Journal of Engineering and Technology》 2019年第1期122-128,共7页
With the development of oilfield exploration and mining, the research on continental oil and gas reservoirs has been gradually refined, and the exploration target of offshore reservoir has also entered the hot studyst... With the development of oilfield exploration and mining, the research on continental oil and gas reservoirs has been gradually refined, and the exploration target of offshore reservoir has also entered the hot studystage of small sand bodies, small fault blocks, complex structures, low permeability and various heterogeneous geological bodies. Thus, the marine oil and gas development will inevitably enter thecomplicated reservoir stage;meanwhile the corresponding assessment technologies, engineering measures andexploration method should be designed delicately. Studying on hydraulic flow unit of low permeability reservoir of offshore oilfield has practical significance for connectivity degree and remaining oil distribution. An integrated method which contains the data mining and flow unit identification part was used on the flow unit prediction of low permeability reservoir;the predicted results?were compared with mature commercial system results for verifying its application. This strategy is successfully applied to increase the accuracy by choosing the outstanding prediction result. Excellent computing system could provide more accurate geological information for reservoir characterization. 展开更多
关键词 Low PERMEABILITY Reservoir Offshore OILFIELD Hydraulic FLOW unit FLOW unit IDENTIFICATION data Mining
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Clastic compaction unit classification based on clay content and integrated compaction recovery using well and seismic data 被引量:1
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作者 Zhong Hong Ming-Jun Su +1 位作者 Hua-Qing Liu Gai Gao 《Petroleum Science》 SCIE CAS CSCD 2016年第4期685-697,共13页
Compaction correction is a key part of paleogeomorphic recovery methods. Yet, the influence of lithology on the porosity evolution is not usually taken into account. Present methods merely classify the lithologies as ... Compaction correction is a key part of paleogeomorphic recovery methods. Yet, the influence of lithology on the porosity evolution is not usually taken into account. Present methods merely classify the lithologies as sandstone and mudstone to undertake separate porositydepth compaction modeling. However, using just two lithologies is an oversimplification that cannot represent the compaction history. In such schemes, the precision of the compaction recovery is inadequate. To improve the precision of compaction recovery, a depth compaction model has been proposed that involves both porosity and clay content. A clastic lithological compaction unit classification method, based on clay content, has been designed to identify lithological boundaries and establish sets of compaction units. Also, on the basis of the clastic compaction unit classification, two methods of compaction recovery that integrate well and seismic data are employed to extrapolate well-based compaction information outward along seismic lines and recover the paleo-topography of the clastic strata in the region. The examples presented here show that a better understanding of paleo-geomorphology can be gained by applying the proposed compaction recovery technology. 展开更多
关键词 Compaction recovery Porosity-clay contentdepth compaction model Classification of lithological compaction unit Well and seismic data integrated compaction recovery technology
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“泛珠三角”九省区消费结构的实证研究——基于Panel data下的数量分析
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作者 邓淇中 龙宁 《湖南工程学院学报(社会科学版)》 2007年第4期5-8,25,共5页
通过对"泛珠三角"九省区内的消费现状、影响因素及其产生原因的初步研究,构建了两个计量经济学模型来做进一步的实证分析:其一是利用单位根理论检验区域内消费支出是否具有长期均衡关系;其二是利用面板数据模型估计区域内消... 通过对"泛珠三角"九省区内的消费现状、影响因素及其产生原因的初步研究,构建了两个计量经济学模型来做进一步的实证分析:其一是利用单位根理论检验区域内消费支出是否具有长期均衡关系;其二是利用面板数据模型估计区域内消费结构的差异,期望能以此促进整个"泛珠三角"区域的经济均衡与可持续发展。 展开更多
关键词 面板数据 单位根 固定效应
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基于Feed4JUnit架构的单元测试技术研究与应用 被引量:1
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作者 杨鹏 《软件工程师》 2014年第7期25-27,共3页
软件测试技术在软件质量控制过程中一直起着非常重要的作用。JUnit是被广泛应用的Java单元测试框架,主要测试基于java语言编写的程序代码,用于编写和运行可重复的测试。Feed4JUnit是开源的基于JUnit的扩展,通过使用Feed4JUnit提供的注释... 软件测试技术在软件质量控制过程中一直起着非常重要的作用。JUnit是被广泛应用的Java单元测试框架,主要测试基于java语言编写的程序代码,用于编写和运行可重复的测试。Feed4JUnit是开源的基于JUnit的扩展,通过使用Feed4JUnit提供的注释,用户可以很方便地把测试数据存放在文件或其他数据源。本文分析了应用Feed4JUnit进行单元测试的方法,并通过实际开发示例实现数据与代码分离的测试。 展开更多
关键词 Feed4Junit架构 单元测试 数据源
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数据驱动测试在Nunit框架中的应用
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作者 王敏 陈亚光 《微型机与应用》 2012年第22期10-12,18,共4页
为了解决单元测试工具Nunit本身不支持数据驱动测试的问题,提出了在Nunit框架下实现数据驱动测试的方法。该方法首先将测试类所使用的测试数据基本信息设定在ini文件中,将输入数据及预期结果存放于Excel文件中。随后通过属性标签[TestFi... 为了解决单元测试工具Nunit本身不支持数据驱动测试的问题,提出了在Nunit框架下实现数据驱动测试的方法。该方法首先将测试类所使用的测试数据基本信息设定在ini文件中,将输入数据及预期结果存放于Excel文件中。随后通过属性标签[TestFixtureSetUp]标记的方法动态读取ini文件中的基本信息,再根据这些基本信息读取Excel文件中的测试数据,并将测试数据保存于自定义的结构体数组中供各测试方法使用。该方法有效地实现了测试数据与测试脚本的分离,能降低测试脚本的维护工作量,提高测试效率。 展开更多
关键词 单元测试 Nunit框架 测试脚本 测试数据
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Green Architecture for Dense Home Area Networks Based on Radio-over-Fiber with Data Aggregation Approach
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作者 Mohd Sharil Abdullah Mohd Adib Sarijari +4 位作者 Abdul Hadi Fikri Abdul Hamid Norsheila Fisal Anthony Lo Rozeha A.Rashid Sharifah Kamilah Syed Yusof 《Journal of Electronic Science and Technology》 CAS CSCD 2016年第2期133-144,共12页
The high-density population leads to crowded cities. The future city is envisaged to encompass a large-scale network with diverse applications and a massive number of interconnected heterogeneous wireless-enabled devi... The high-density population leads to crowded cities. The future city is envisaged to encompass a large-scale network with diverse applications and a massive number of interconnected heterogeneous wireless-enabled devices. Hence, green technology elements are crucial to design sustainable and future-proof network architectures. They are the solutions for spectrum scarcity, high latency, interference, energy efficiency, and scalability that occur in dense and heterogeneous wireless networks especially in the home area network (HAN). Radio-over-fiber (ROF) is a technology candidate to provide a global view of HAN's activities that can be leveraged to allocate orthogonal channel communications for enabling wireless-enabled HAN devices transmission, with considering the clustered-frequency-reuse approach. Our proposed network architecture design is mainly focused on enhancing the network throughput and reducing the average network communications latency by proposing a data aggregation unit (DAU). The performance shows that with the DAU, the average network communications latency reduces significantly while the network throughput is enhanced, compared with the existing ROF architecture without the DAU. 展开更多
关键词 data aggregation unit dense homearea network green architecture heterogeneousnetwork radio-over-fiber.
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新型电力系统数据跨域流通泛安全边界防护技术 被引量:5
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作者 郭少勇 刘岩 +3 位作者 邵苏杰 臧志斌 杨超 亓峰 《电力系统自动化》 EI CSCD 北大核心 2024年第6期96-111,共16页
新型电力系统建设涉及多业务系统、多部门、多方主体间进行海量、异构数据的交互和共享,电力数据的内外部网络环境与安全形势日趋复杂化,数据流通的脆弱性风险加剧。首先,分析新型电力系统下数据流的类型与特性,概括电力数据流通安全防... 新型电力系统建设涉及多业务系统、多部门、多方主体间进行海量、异构数据的交互和共享,电力数据的内外部网络环境与安全形势日趋复杂化,数据流通的脆弱性风险加剧。首先,分析新型电力系统下数据流的类型与特性,概括电力数据流通安全防护面临的新形势;其次,基于专用数据处理器(DPU)的高性能流量编排和多功能安全网关能力,构建面向电力数据跨域流通安全增强的泛安全边界,凭借数据面可编程技术沟通网络安全与数据安全双维度安全能力,提出基于DPU的数据跨域流通协同防护技术应用方案;最后,阐释DPU在不同电力通信网络层次的部署方式、价值与关键技术,分析现阶段DPU在电力领域应用存在的挑战。 展开更多
关键词 新型电力系统 数据流通 专用数据处理器 数据安全 网络安全 安全防护
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英国医疗健康大数据Care.data的前车之鉴 被引量:5
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作者 姚国章 《南京邮电大学学报(社会科学版)》 2017年第3期38-50,共13页
英国有着世界领先的医疗健康保障体系,积累了丰富而又宝贵的数据资源,为大数据在医疗健康领域的应用创造了良好的条件,Care.data项目是其重要的探索。但在项目实施过程中由于缺乏必要的规划部署和试点探索、没有正确处理好家庭医生与项... 英国有着世界领先的医疗健康保障体系,积累了丰富而又宝贵的数据资源,为大数据在医疗健康领域的应用创造了良好的条件,Care.data项目是其重要的探索。但在项目实施过程中由于缺乏必要的规划部署和试点探索、没有正确处理好家庭医生与项目的关系、缺乏公众的理解和支持、不当的商业开发及技术方案不够完善等原因最终导致了项目失败,为我国医疗健康大数据的开发利用提供了前车之鉴。我国正在大力推进大数据在医疗健康领域的应用,必须从英国的实践中汲取教训,以少走不必要的弯路。 展开更多
关键词 大数据 Care.data 医疗健康 隐私保护 英国
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HtmlUnit在网上招聘系统中的应用
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作者 陈免慧 沈炜 《电脑知识与技术(过刊)》 2015年第7X期61-63,共3页
该文提出采用Htmlunit框架能够轻易的解析javascript页面、获取动态Ajax页面数据、模拟浏览器交互和数据的自动抓取功能,并且加上XPath完成其他各个渠道职位及候选人的匹配查找和解析入库。最后通过实验,证明了Htmlunit在招聘系统中的... 该文提出采用Htmlunit框架能够轻易的解析javascript页面、获取动态Ajax页面数据、模拟浏览器交互和数据的自动抓取功能,并且加上XPath完成其他各个渠道职位及候选人的匹配查找和解析入库。最后通过实验,证明了Htmlunit在招聘系统中的应用。 展开更多
关键词 数据采集 Html unit AJAX 招聘系统
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RELIABILITY ASSESSMENT OF ENTROPY METHOD FOR SYSTEM CONSISTED OF IDENTICAL EXPONENTIAL UNITS 被引量:5
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作者 SunYouchao ShiJun 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2004年第4期502-506,共5页
The reliability assessment of unit-system near two levels is the mostimportant content in the reliability multi-level synthesis of complex systems. Introducing theinformation theory into system reliability assessment,... The reliability assessment of unit-system near two levels is the mostimportant content in the reliability multi-level synthesis of complex systems. Introducing theinformation theory into system reliability assessment, using the addible characteristic ofinformation quantity and the principle of equivalence of information quantity, an entropy method ofdata information conversion is presented for the system consisted of identical exponential units.The basic conversion formulae of entropy method of unit test data are derived based on the principleof information quantity equivalence. The general models of entropy method synthesis assessment forsystem reliability approximate lower limits are established according to the fundamental principleof the unit reliability assessment. The applications of the entropy method are discussed by way ofpractical examples. Compared with the traditional methods, the entropy method is found to be validand practicable and the assessment results are very satisfactory. 展开更多
关键词 Reliability synthesis data conversion Entropy method Information quantity Exponential unit
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An Examination of Male and Female Monthly Employment Rates over Time in Canada and the United States Using Hidden Markov Probability Models
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作者 William H. Laverty Ivan W. Kelly 《Open Journal of Statistics》 2018年第5期837-845,共9页
In this paper, we will illustrate the use and power of Hidden Markov models in analyzing multivariate data over time. The data used in this study was obtained from the Organization for Economic Co-operation and Develo... In this paper, we will illustrate the use and power of Hidden Markov models in analyzing multivariate data over time. The data used in this study was obtained from the Organization for Economic Co-operation and Development (OECD. Stat database url: https://stats.oecd.org/) and encompassed monthly data on the employment rate of males and females in Canada and the United States (aged 15 years and over;seasonally adjusted from January 1995 to July 2018). Two different underlying patterns of trends in employment over the 23 years observation period were uncovered. 展开更多
关键词 EMPLOYMENT Trends Hidden MARKOV Models Multivariate data CANADA unitED States
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Subject Oriented Autonomic Cloud Data Center Networks Model
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作者 Hang Qin Li Zhu 《Journal of Data Analysis and Information Processing》 2017年第3期87-95,共9页
This paper investigates autonomic cloud data center networks, which is the solution with the increasingly complex computing environment, in terms of the management and cost issues to meet users’ growing demand. The v... This paper investigates autonomic cloud data center networks, which is the solution with the increasingly complex computing environment, in terms of the management and cost issues to meet users’ growing demand. The virtualized cloud networking is to provide a plethora of rich online applications, including self-configuration, self-healing, self-optimization and self-protection. In addition, we draw on the intelligent subject and multi-agent system, concerning system model, strategy, autonomic cloud computing, involving independent computing system development and implementation. Then, combining the architecture with the autonomous unit, we propose the MCDN (Model of Autonomic Cloud Data Center Networks). This model can define intelligent state, elaborate the composition structure, and complete life cycle. Finally, our proposed public infrastructure can be provided with the autonomous unit in the supported interaction model. 展开更多
关键词 AUTONOMIC CLOUD Computing AUTONOMOUS unit data Center SELF-CONFIGURATION Service DESCRIPTION
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Research on Optimization for Units Start During Power System Restoration
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作者 Jun Chen Wei-xing Zhao +4 位作者 Hua-ying Su Jia-lin Bai Nian Liu Xiao-yan Qiu Qian Liao 《Energy and Power Engineering》 2013年第4期708-712,共5页
Considering units starting and network constraints and the concept of optimization period,a optimization model which is a typical multi-constraint knapsack problem is established to solve the selection optimization pr... Considering units starting and network constraints and the concept of optimization period,a optimization model which is a typical multi-constraint knapsack problem is established to solve the selection optimization problem of units starting in power system restoration period in this paper, and the objective of the model is to maximize the total power generation capability. A relative effectiveness assessment based on a improving data envelopment analysis is adopted to select the initial units to be started, genetic algorithms are employed to solve the knapsack problem to determine the most reasonable units be started at the current time. Finally, IEEE-39 bus system simulation result proves that the proposed model is feasible and effective. 展开更多
关键词 POWER system unitS START data envelopment analysis KNAPSACK PROBLEM
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多源地理产品数据的元数据统一设计与采集管理技术
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作者 刘阳成 廖宁 +3 位作者 左大伟 谢玉波 苏旭明 张鹏 《北京测绘》 2024年第3期332-336,共5页
面向多源地理产品数据管理应用的需求,明确了本文讨论的地理产品数据的范畴,分析了地理产品数据的存储组织及应用特点。基于存储组织需求,统一设计了数据大类小类两级分类目录及类别编码,设计了地理数据产品的元数据采集规范。提出了数... 面向多源地理产品数据管理应用的需求,明确了本文讨论的地理产品数据的范畴,分析了地理产品数据的存储组织及应用特点。基于存储组织需求,统一设计了数据大类小类两级分类目录及类别编码,设计了地理数据产品的元数据采集规范。提出了数据集-数据单元两级元数据的设计理念以便满足不同数据粒度的管理需求,分别设计了数据集元数据和数据单元元数据的详细组成,统一设计了空间地理产品数据与非空间地理产品数据的元数据,明确了数据集目录和数据单元的命名原则。设计并实现了能够自动采集多源地理产品元数据的软件,实现了基于统一元数据设计的数据管理软件。结果表明,这种方法能够满足用户对多源地理产品数据的统一存储组织、多粒度管理、高效便捷检索等需求。 展开更多
关键词 地理产品数据元数据 数据集 数据单元 元数据采集 数据管理
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