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虚拟数据交换子平台设计与实现 被引量:2
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作者 江恭和 武友新 +1 位作者 李庆华 龚磊 《计算机工程与设计》 CSCD 北大核心 2012年第10期4028-4032,共5页
为解决传统数据交换平台建设模式中平台重复建设、多级数据交换实施难度大的问题,提出了在一个公共数据交换平台上建设多个虚拟交换子平台的模式。通过对多协议标签交换虚拟专用网的研究,提出虚拟交换子平台的总体架构。该架构在一个公... 为解决传统数据交换平台建设模式中平台重复建设、多级数据交换实施难度大的问题,提出了在一个公共数据交换平台上建设多个虚拟交换子平台的模式。通过对多协议标签交换虚拟专用网的研究,提出虚拟交换子平台的总体架构。该架构在一个公共数据交换平台上创建多个虚拟交换子平台,采用用户权限隔离、数据库模式隔离、标签交换、路由隔离、密钥隔离多种技术保证各子平台上数据传输的独立性和安全性。此外,引入中心交换和路由机制将传统的点对点交换模式变为星型交换模式。项目实践表明,该模式能够有效避免平台重复建设、降低实施成本。 展开更多
关键词 虚拟数据交换平台 标签交换 路由隔离 密钥隔离 路由转发表 数据交换平台
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GeoJSON在异构地理信息数据集成中的应用 被引量:7
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作者 王东兴 朱翊 《测绘与空间地理信息》 2018年第6期138-140,146,共4页
针对基于可扩展标记语言(XML)的地理信息数据交换平台存在数据冗余量大、传输效率低、通用性差、难以在网络地理信息系统中应用等问题,本文提出了一种基于GeoJSON的异构地理信息数据集成模型。模型采用GeoJSON作为技术主线,以数据交换... 针对基于可扩展标记语言(XML)的地理信息数据交换平台存在数据冗余量大、传输效率低、通用性差、难以在网络地理信息系统中应用等问题,本文提出了一种基于GeoJSON的异构地理信息数据集成模型。模型采用GeoJSON作为技术主线,以数据交换池为核心,通过数据交换池建立应用系统与各异构系统之间的联系,并利用数据交换子节点建立数据交换池与各异构系统的通信连接,对GeoJSON信息流进行上传与下载等操作。实验表明:同XML相比,GeoJSON信息流提高了数据传输效率。 展开更多
关键词 XML GeoJSON 异构数据集成 数据交换 数据交换节点
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办公自动化与宽带化 被引量:1
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作者 王启智 《办公自动化(综合月刊)》 2009年第5期4-8,共5页
本文首先介绍了现代办公自动化的含义、完整的办公自动化系统的三个层次、现代办公自动化的特点、现代办公自动化的发展模式;其次介绍了宽带化中关于带宽的含义、我国宽带用户比例、宽带宽到什么程度和宽带网势在必行;最后论述了我国现... 本文首先介绍了现代办公自动化的含义、完整的办公自动化系统的三个层次、现代办公自动化的特点、现代办公自动化的发展模式;其次介绍了宽带化中关于带宽的含义、我国宽带用户比例、宽带宽到什么程度和宽带网势在必行;最后论述了我国现代办公自动化与宽带化之间的关系,探讨了宽带化为现代办公自动化提供了更加宽阔的网络环境、宽带化为移动办公模式的建立提供了前提条件、宽带化为现代办公自动化中的远程教育、医疗、会议等创造了基础条件和在宽带化的形势下将产生新的办公自动化系统的预想。 展开更多
关键词 办公自动化 宽带化 带宽 集成化 智能化 多媒体化电 子数据交换 办公人员的高素质化 现代办公自动化系统
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Study on Apparel EDI Standardization Based on XML
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作者 杨以雄 陶珂 陈榕 《Journal of Donghua University(English Edition)》 EI CAS 2005年第2期105-109,共5页
The realization of paperless trading in apparel industry by application of EDI has become the requirement of the new century. In this paper the necessity for EDI standardization is proved, and the coding of domestic a... The realization of paperless trading in apparel industry by application of EDI has become the requirement of the new century. In this paper the necessity for EDI standardization is proved, and the coding of domestic apparel EDI message standard is put forward. 展开更多
关键词 apparel industry EDI STANDARDIZATION
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Effect of Distances from Different Trees Species on the Properties of Mollic Horizon
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作者 Mohammed Ali Fayyadh 《Journal of Agricultural Science and Technology(A)》 2013年第8期581-591,共11页
The study area is located in Duhok province-Kurdistan region-Northern Iraq and including two locations the first location is situated in Galbook village and the vegetation cover is trees of (Quercus aegilops L.), th... The study area is located in Duhok province-Kurdistan region-Northern Iraq and including two locations the first location is situated in Galbook village and the vegetation cover is trees of (Quercus aegilops L.), the second location is situated in Koradeer village that covered with threes of Prunus dulcis (Mill.) Webb.. Disturbed surface soil samples at depth 0-30 cm were collected at four different distances (1, 5, 10 and 15 m) from the tree with randomized selection three trees in each study location. Soil organic matter decreases with increasing distances from tree in both locations under two different trees species, which is attributed to the effect of tree crown. Ordinarily, organic matter content in both locations correspond to the requirements of Mollisols. Statistical analysis of data showed significant differences in organic matter content between locations. Cation exchange capacity is high under tree crown and decreasing with distances from tree in both locations, as a result of decreasing organic matter and increasing calcium carbonate with distances. Commonly soil pH is slightly increased with increasing distances from tree because of increasing calcium carbonate with distances and decreasing organic matter content. Calcium was not uniform with distances and Mg decreasing with distances in both locations. The values of fine clay/coarse clay and fine clay/total clay of soil samples confirm development of the soils under study. Porosity percentage under tree crown is high and decreasing with distances. Soil bulk density was increased with distances in both locations, as a result of decreasing organic matter content with distances. This study aims to explain the effect of tree distances and species on the mollic horizon properties. 展开更多
关键词 Tree species DISTANCES MOLLISOLS physical properties chemical properties.
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PEM Fuel Cell System Evaluation Using Operational Data and Updated Matlab/Simulink Simulation Tools
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作者 Naxakis Ioannis Marinis Andreas +2 位作者 Nakis Stavros Pyrgioti Eleftheria loannis Milias-Argitis 《Journal of Energy and Power Engineering》 2012年第12期1911-1917,共7页
The aim of this paper is the evaluation of the performance of a low pressure PEM (proton exchange membrane) fuel cell stack to step load changes, which are characteristic of standalone fuel cell system applications.... The aim of this paper is the evaluation of the performance of a low pressure PEM (proton exchange membrane) fuel cell stack to step load changes, which are characteristic of standalone fuel cell system applications. The goal is a better understanding of the electrical behavior of the FC (fuel cell), as a result of the electrochemical processes, via the cell's voltage characteristic during transient response. While changing the load, the performance of significant parameters affected such as temperature, pressure, purge status etc. are registered and evaluated. The analysis and experiment are based on a low pressure 1.2 kW PEM fuel cell stack (NEXAS power module). Then, the experiment is simulated using Matlab/Simulink tools, while PCU (power conditioning units) are added in order to control power flow for enhanced performance. Finally, both operational and simulation data are compared to each other showing that simple PCUs applications can improve system's efficiency. 展开更多
关键词 Distributed generation units). dynamic-transient response PEM fuel cell standalone power systems PCU (power conditioning
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Salic Horizons in Soils of the USA
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作者 J. G. BOCKHEIM A. E. HARTEMINK 《Pedosphere》 SCIE CAS CSCD 2013年第5期600-608,共9页
The taxonomic hierarchy and nationwide distribution of soils with a salic horizon were studied using the USA Natural Resources Conservation Service Soil Survey Geographic (SSURGO) Database to provide a more holistic... The taxonomic hierarchy and nationwide distribution of soils with a salic horizon were studied using the USA Natural Resources Conservation Service Soil Survey Geographic (SSURGO) Database to provide a more holistic view of the role of soil-forming factors in pedogenesis than from isolated case studies. Soils with a salic horizon occupied an area of 11 000 km2, i.e., 0.1% of land area in the contiguous USA. These soils occur narrowly in three great groups (Aquisalids, Haplosalids and Halaquepts), 11 subgroups, and 97 soil series. Soils with a salic horizon commonly had a mesic (50% of soil series) or thermic (19%) soil-temperature class, an aquic (89%) soil-moisture class, a mixed mineral class (79%), a calcareous (52%) reaction class, a superaztive (59%) cation exchange activity class, and a fine (24% of soil series), fine-loamy (24% of soil series), or fine-silty (19% of soil series) particle-size class. Soils with a salic horizon were concentrated in the Basin and Range Province of western USA. The key pedogenic processes leading to the development of salic horizons were salinization, gleization, and calcification, with some evidence for argilluviation and silicification. 展开更多
关键词 saline soils soil classification solonchak
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The Majorana neutrino mass matrix indicated by the current data
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作者 ZHANG XinYi MA BoQiang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2015年第7期36-48,共13页
The Majorana neutrino mass matrix combines information from the neutrino masses and the leptonic mixing in the flavor basis. Its invariance under some transformation matrices indicates the existence of certain residua... The Majorana neutrino mass matrix combines information from the neutrino masses and the leptonic mixing in the flavor basis. Its invariance under some transformation matrices indicates the existence of certain residual symmetry. We offer an intuitive display of the structure of the Majorana neutrino mass matrix, using the whole set of the oscillation data. The structure is revealed depending on the lightest neutrino mass. We find that there are three regions with distinct characteristics of structure. A group effect and the μ-T exchange symmetry are observed. Six types of texture non-zeros are shown. Implications for flavor models are discussed. 展开更多
关键词 NEUTRINO Majorana mass matrix oscillation data
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