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cii网络景气指数分析报告

互联网周刊 2000年第31期 12-页

作者：周廖宏互联网研究与发展中心(cii)

由于资本市场的特殊性,不能分地区地进行测算,所以网络股没有纳入本次的指标体系中。但是有关网络股历年的数据都可以获得,可以进行纵向的比较,因此我们将网络景气指标单列出来分析。数据说明目前国内市场中没有一家上市公司主营网络... 详细信息

由于资本市场的特殊性,不能分地区地进行测算,所以网络股没有纳入本次的指标体系中。但是有关网络股历年的数据都可以获得,可以进行纵向的比较,因此我们将网络景气指标单列出来分析。数据说明目前国内市场中没有一家上市公司主营网络业,大都是参股或收购网站,而涉及网络业务的上市公司目前接近200家,我们选取了20只代表性的网络股股票作为样本股,它们是:浙江广厦、金丰投资、乐山电力、英豪科教、海虹控股、托普软件、振华科技、中通客车、上海梅林、青旅控股、国嘉实业、青岛海尔、综艺股份、科利华、上海医药、北新建材、青鸟天桥。

关键词：市盈率股市股票市场收市价涨跌率 cii

Data Center Power System Stability-Part II: System Modeling and Analysis

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CSEE Journal of Power and Energy Systems 2022年第2期8卷 420-438页

作者： Jian Sun Melaku Mihret Mauricio Cespedes David Wong Mike Kauffman Rensselaer Polytechnic Institute-ECSE 1108th Street Room CII 8015Troy 12180United States Meta Platforms Inc. 1601 Willow RdMenlo ParkCalifornia 94025-1452United States

This is the second part of a two-part paper on stability study of data center power systems by impedance-based *** the basis for this application,Part I[1]developed new impedance models for power supplies that are the most dominant loads in data *** second part presents system modeling and analysis methods that can support practical data center power system design to ensure *** proposed methods comprise:1)building distribution network modeling by impedance scaling;2)system modeling and model reduction based on equivalent source impedance;3)system stability analysis in the sequence domain to include zero-sequence dynamics;and 4)expansion of system models and analyses to account for network asymmetry and uneven *** methods are used to characterize practical resonance problems observed in data centers,explain their root causes,and develop *** systems using Y-connected power supply units(PSUs),the zero sequence is identified as the weakest link and the first to become *** expanded system model and analysis reveal a new,differential-mode instability that is responsible for high frequency *** guarantee system stability,new impedance-based product and system design specifications are developed based on sufficient conditions derived from the Nyquist stability *** and field measurements are presented to substantiate the proposed methods and conclusions.

关键词： Data center power systems frequency-domain methods impedance modeling system stability system resonance

Data Center Power System Stability-Part I: Power Supply Impedance Modeling

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CSEE Journal of Power and Energy Systems 2022年第2期8卷 403-419页

作者： Jian Sun Mingchun Xu Mauricio Cespedes Mike Kauffman Rensselaer Polytechnic Institute-ECSE 1108th Street Room CII 8015Troy 12180United States Meta Platforms Inc. 1601 Willow RdMenlo ParkCalifornia 94025-1452United States

This two-part paper presents methods to predict,characterize and ensure the stability of data center power systems based on impedance *** work was motivated by recent power system resonance incidents in new data *** I presents new input impedance models for single-phase power supply units(PSUs)to enable this *** impedance models of single-phase PSU cannot meet the requirements of this application because they exclude DC voltage control that affects system stability at low frequency,or are in a dq reference frame that cannot handle the complexity of data center power *** developed new models include DC bus dynamics and are directly in the phase domain to simplify system stability analysis,avoiding the need for multiple-input-multiple-output(MIMO)system models and the generalized Nyquist criterion that are difficult to apply but necessary with dq-frame *** the converter and system level models also include the coupled current response that is characteristic of AC-DC converters and important for system stability at low *** simple form of the models and system stability analysis directly in the phase domain also make it possible to develop new PSU design methods and performance specifications that together will ensure the stability of new data center power *** developed models are validated by laboratory measurements and are used in Part II of the work to study data center power system stability.

关键词： Data center power systems frequency-domain methods impedance modeling system stability system resonance

Hydrological Modelling of Small Gauged and Ungauged Mountainous Watersheds Using SWAT—A Case of Western Ghats in India

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Journal of Water Resource and Protection 2021年第7期13卷 455-477页

作者： Kapil Kumar Narula Shilpa Nischal Executive Director CII Triveni Water Institute (Center of Excellence on Water) Confederation of Indian Industry New Delhi India Senior Counsellor CII Triveni Water Institute Confederation of Indian Industry New Delhi India

Mountainous forested watersheds are important hydrologic systems that are responsible for much of the water supply and run-of-the-river hy-dropower schemes in many parts of the world. In India, the Western Ghats are one of such important hydrologic systems located in southern peninsular region. Several of these watersheds are ungauged. The Soil and Water Assessment Tool (SWAT) has been used to model streamflows for two mountainous forested watersheds, namely, Gurupur (699 km2) (a gauged watershed) and Upper Payaswini (44.6 km2) (an ungauged wa-tershed). Model calibration and validation are performed using monthly and daily streamflow data for the gauged watershed. Sample flow values obtained over a limited period were used for validation of ungauged wa-tershed. Flow duration curves (FDCs) have been derived to assess per-centile flow distributions. Model performance is evaluated using Nash-Sutcliffe coefficient (ENS), percent bias (PBIAS), coefficient of de-termination (R2) and comparison of percentile flow values obtained from observed and simulated FDCs. Sensitivity analysis with Latin Hypercube One-factor-At-a-Time (LH-OAT) indicates five soil-land use related pa-rameters namely, soil available water capacity (SOL_AWC), soil evapora-tion compensation factor (ESCO), soil depth (SOL_Z) and layers, groundwater baseflow (ALPHA_BF), and curve number (CN2 (forest & agriculture)), to be sensitive for simulating both gauged and ungauged wet mountainous forested watersheds. Study shows that lateral flows from dynamic sub-surface zones in such watersheds contribute substan-tially to the total water yield.

关键词： SWAT Hydrology Ungauged Mountainous Sensitivity Analysis

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满足频率扩展需要的继电器

今日电子 2001年第4期 18-19页

作者： MICHAEL BALDWIN cii Technologies公司

减小封装体积并提升频率驱动能力来满足微型的1Hz至6GHz微波断电器的需要

关键词：频率扩展微波继电器频率驱动封装

A Survey on the Vehicle Routing Problem and Its Variants

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Intelligent Information Management 2012年第3期4卷 66-74页

作者： Suresh Nanda Kumar Ramasamy Panneerselvam Department of Management Studies Pondicherry University Pondicherry India Education Department CII Institute of Logistics Chennai India

In this paper, we have conducted a literature review on the recent developments and publications involving the vehicle routing problem and its variants, namely vehicle routing problem with time windows (VRPTW) and the capacitated vehicle routing problem (CVRP) and also their variants. The VRP is classified as an NP-hard problem. Hence, the use of exact optimization methods may be difficult to solve these problems in acceptable CPU times, when the problem involves real-world data sets that are very large. The vehicle routing problem comes under combinatorial problem. Hence, to get solutions in determining routes which are realistic and very close to the optimal solution, we use heuristics and meta-heuristics. In this paper we discuss the various exact methods and the heuristics and meta-heuristics used to solve the VRP and its variants.

关键词： Vehicle Routing Problem Exact Methods Heuristics Meta-heuristics VRPTW Optimization Ant Colony Optimization Genetic Algorithms

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论职业院校管理的精细化发展

统计研究 2014年第11期31卷 24-28页

作者：国家统计局社科文司“中国创新指数(cii)研究”课题组国家统计局社科文司“中国创新指数cii研究”课题组

文章介绍了精细化管理的理论内涵及其对高校管理的启示,认为精细化管理在新升格专科层次职业院校突破自身发展瓶颈中具有重大意义。同时,阐述了精细化管理将是新升格专科层次职业院校管理的有效方式和发展方向,并从学校的战略规划及管... 详细信息

文章介绍了精细化管理的理论内涵及其对高校管理的启示,认为精细化管理在新升格专科层次职业院校突破自身发展瓶颈中具有重大意义。同时,阐述了精细化管理将是新升格专科层次职业院校管理的有效方式和发展方向,并从学校的战略规划及管理模式、人才培养体系、校园文化建设等方面,提出实施精细化管理的策略。

关键词：精细化管理新升格专科层次职业院校发展方向

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几笔明细账算出盈亏事

中国经济周刊 2000年第33期 18-18页

作者：姜奇平胡泳互联网研究与发展中心(cii)

新经济有两个基本面,一是宏观的,一是微观的。宏观意义上的新经济,以高增长、高就业和低通胀为标志;微观意义上的新经济,以电子商务为标志。有人说,新经济就是电子商务经济,这实际上强调的是新经济的微观层面。相应地,人们对新经济有两... 详细信息

新经济有两个基本面,一是宏观的,一是微观的。宏观意义上的新经济,以高增长、高就业和低通胀为标志;微观意义上的新经济,以电子商务为标志。有人说,新经济就是电子商务经济,这实际上强调的是新经济的微观层面。相应地,人们对新经济有两个基本的期待,一是国富,二是民富,即国家求财富与企业求赢利。当前围绕新经济的思潮中,赢利问题是中心,即首先考虑微观问题。人们

关键词：经济赢利产业交易成本交易费用交易额上网资费交易量效益指数上网费用效益水平

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用阴极射线管显示器研究影响色差知觉的因素

光学学报 2001年第4期21卷 426-432页

作者：崔桂华李为范秋梅 Luo M R 北京理工大学光电工程系颜色科学与工程国家重点实验室北京100081 cii University of DerbyDerbyDE223HLUK

利用计算机控制的阴极射线管显示器研究影响色差知觉的因素。由一组观察者采用灰标法判断以 16组不同参数显示的色样对的色差 ,获取了大量的观察数据。初步分析处理的结果表明 ,在本实验研究的各种观察因素中 ,色样轮廓线和背景颜色对... 详细信息

利用计算机控制的阴极射线管显示器研究影响色差知觉的因素。由一组观察者采用灰标法判断以 16组不同参数显示的色样对的色差 ,获取了大量的观察数据。初步分析处理的结果表明 ,在本实验研究的各种观察因素中 ,色样轮廓线和背景颜色对色差知觉的影响比较明显 ;在所比较的国际照明委员会 1994年推荐的色差公式(CIE94)、国际照明委员会 1976年推荐的颜色空间和色差公式 (CIELAB)、伯兰福特色差公式 (BFD)和英国颜色测量协会色差公式 (CMC)四种色差公式中 ,BFD预测色差知觉的结果最好 ,CIELAB最差。在分析比较阴极射线管模拟色样和纺织品表面色样的色差评估数据基础上 ,得出了人眼对阴极射线管荧屏色的色差知觉与表面色的色差知觉达到最接近的两种观察条件。

关键词：色差色差公式目视评估灰标法阴极射线管显示器色度学产品颜色质量控制指标