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Energy and Power Engineering 2013年第3期5卷 225-235页

作者： Kadri Kadriu Ali Gashi Ibrahim Gashi Ali Hamiti Gazmend Kabashi Faculty of Electric Engineering and Computer Sciences University of Prishtina Prishtina Kosovo KOSTT—Kosovo Transmission System and Market Operator Prishtina Kosovo

This paper analyses the synchronization problem of a generator onto power system without satisfying synchronization condition. The main focus of the paper is on the impact of the dc component of the current in the high voltage circuit breaker during its close-open operating cycle. Using real time measurements of currents/voltages and angles during the close-opening cycle of high voltage generator circuit breaker and the impact of the dc component of current in context of interrupting large magnitude of current from the circuit breaker. In addition, the paper describes a study case model and the results of simulations performed using the software EMTP-ATP of an actual incident that occurred during the inadvertent synchronization of a large 339 MW, 24 kV generator to the grid.

关键词： High Voltage Generator Circuit Breaker dc component of Current Asynchronous Connection Delay Current Zero

A Methodology for Identification of Weather Sensitive component of Electrical Load Using Empirical Mode Decomposition Technique

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Energy and Power Engineering 2013年第4期5卷 293-300页

作者： Nahid-Al- Masood Q. Ahsan Department of Electrical and Electronic Engineering Bangladesh University of Engineering and Technology Dhaka Bangladesh

The expansion planning and operation of all three sectors, generation, transmission and distribution, of power system essentially require load forecasting. Weather conditions have significant impacts on forecasted load, especially short-term and mid-term. A momentous portion of the electrical energy is consumed, especially in cold or hot countries, to mitigate the impact of weather on the daily life of human society. Usually, weather dependent component of load is identified by fitting appropriate non-linear curve to the scatter plot of weather-load model. This technique some times shows lower correlation with weather variables. This paper proposes a new methodology to identify the weather sensitive component of electrical load using empirical mode decomposition (EMD) technique. The proposed methodology is applied to the daily peak load of Dhaka zone of Bangladesh Power System (BPS) of the year 2012. A detailed numerical process to evaluate the weather sensitive portion of the load is also presented. The proposed methodology is validated through statistical error evaluation process. Finally the salient features of the results are discussed.

关键词： Load Weather Sensitive component EMD Temperature-Humidity Index Correlation Coefficient

The Principle and Practice of the Deviation of Power Frequency component Relay on High Voltage Transmission Line

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Electricity 1998年第4期 19-24页

作者： Shen Guorong (Professor and Senior Engineer of NARI)

The research and development of ultra high speed protective relay of transmission line has got great interest and attention of protective relay engineer over the world. Several versions and schemes of ultra high speed relay have been studied and designed in recent twenty years. But only a few of them have got actual apiication in the power system. The relay based on the deviation of power frequency component (DPFC) can get very high reliability with ultra high speed so it has got wide application in Chinese power system. Thousands relay sets have been applied and its operation experience verifies their excellent performance. This paper summarizes the course of the development of the uItra high speed protective relay and compares the merits and defects of the main schemes which have been developed. The principle and successful pratice of the ultra high speed protection based on DPFC reIay are introduced.

关键词： ultra high speed protective relay deviation of power frequency component

Research and Design of UUV Navigation and Control Integrative Simulation System Based on component

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Intelligent Information Management 2012年第5期4卷 181-187页

作者： Shengjie Wang Fengju Kang Underwater Information and Control State Key Lab Marine College of Northwestern Polytechnical University Xi’an China

This paper uses the component-based technology and the object oriented simulation technology to analyze the UUV navigation and control integration simulation system. We divide the system into components based on its structure, and describe every component using active diagram. By using the component-based technology, the system described here is easier to extended and be reused. At last, it realizes the whole UUV integrated navigation simulation course using the system to validate the availability.

关键词： UUV Integrative Simulation component

Proving and Extending Greub-Reinboldt Inequality Using the Two Nonzero component Lemma

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Advances in Linear Algebra & Matrix Theory 2014年第2期4卷 120-127页

作者： Morteza Seddighin Indiana University East Richmond IN 47374 USA

We will use the author’s Two Nonzero component Lemma to give a new proof for the Greub-Reinboldt Inequality. This method has the advantage of showing exactly when the inequality becomes equality. It also provides information about vectors for which the inequality becomes equality. Furthermore, using the Two Nonzero component Lemma, we will generalize Greub-Reinboldt Inequality to operators on infinite dimensional separable Hilbert spaces.

关键词： Greub-Reinboldt Inequality Two Nonzero component Lemma

Object-component Development of Application and Systems Theory and Practice

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Journal of Software Engineering and Applications 2014年第9期7卷 756-769页

作者： Ekaterina Lavrischeva Andrey Stenyashin Andrii Kolesnyk Institute of Software Systems of NAS Kiev Ukraine

The Оbject-Componet Development (ОCD) is a variety of the compositional programmings, where a role of elements of assembling is warmed by objects, interfaces and components. For developing application systems, the theory of design of subject domain based on Frege object theory is developed, together with the presentation of their functions by methods and interfaces with formal annotations for saving them in libraries. Mathematical vehicle ОCDs are models, methods, algebra of operations of objective analysis and their configuring with the use of the component algebra of running, evolution and transformation of data types that are passed between objects through interfaces. Row of the theoretical and applied aspects ОCD was realized in the instrumental-technological complex (IТC) as CASE-instruments of web-site http://***. With their help the students can study, create, model, certify and accumulate or configure the objects and components into repository of ITC, and also assemble together from them in more complex applied systems.

关键词： Object Reuses Theory Object Model component Interface Applied Systems Exchanging Interoperability Operations Evolution Systems

REVIEW AND PROSPECTS OF HYDROLOGICAL component DEVELOPMENT OF ESCAP/WMO TYPHOON COMMITTEE

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Tropical Cyclone Research and Review 2018年第1期7卷 11-22页

作者： JINPING LIU YOSHIO TOKUNAGA HYOSEOB CHO JINXING WANG ESCAP/WMO Typhoon Committee Secretariat International Centre for Water Hazard and Risk Management Public Works Research Institute Han River Flood Control Office Ministry of Land Infrastructure and Transport Water Information Center Ministry of Water Resources

Hydrological component has been one of three essential parts of ESCAP/WMO Typhoon *** Working Group on Hydrology(WGH)established at TC 33rd Session in 2000 is the first working group among three basic components of the Committee,which has been repeatedly recognized as the most active component in the Committee who has integrated conducted successfully a number of cooperation projects and integrated actions among *** the past decade,WGH has implemented wide range activities under the framework of Strategic Plan of the *** achievement of those cooperation projects played very important roles in promoting the capacity building on hydrological monitoring,forecasting and early warning among *** paper introduced the Term of Reference for WGH and its high priorities,and summarized the activities conducted in recent *** paper also reviewed the progresses in TC Members on hydrological observation and monitoring network,hydrological data collection and transmission,hydrological information and forecasting,and establishment of flood forecasting *** paper also pointed out the development direction and the area to be enhanced for hydrological component in future,including:(1)application of QPE/QPF in flood forecasting and establishment of the coupled hydro-meteorological modeling;(2)development of impact-based,risk-based and community-based flood forecasting and warning system,including storm surge,urban flood,sediment disaster(flash flood,landslide and mudflow);and(3)application of internet of things(IOT),big data,cloud computing,and mobile internet in flood monitoring,forecasting and early warning,and better response,particularly in flood inundation mapping and QPE/QPF products application.

关键词： Typhoon Committee Hydrological component development review prospect

SOFTWARE RELIABILITY MODEL FOR component INTERACTION MODE

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Journal of Electronics(China) 2011年第Z1期 632-642页

作者： Wang Qiang Lu Yang Xu Zijun* Han Jianghong(School of Computer & Information,Hefei University of Technology,Hefei 230009,China) *(GOCOM Information Technology Co.,LTD,Hefei 230088,China)

With the rapid progress of component technology,the software development methodology of gathering a large number of components for designing complex software systems has ***,how to assess the application reliability accurately with the information of system architecture and the components reliabilities together has become a knotty *** this paper,the defects in formal description of software architecture and the limitations in existed model assumptions are both ***,a new software reliability model called component Interaction Mode(CIM) is *** this model,the problem for existed component-based software reliability analysis models that cannot deal with the cases of component interaction with non-failure independent and non-random control transition is *** last,the practice examples are presented to illustrate the effectiveness of this model.

关键词： component Connector Software architecture Reliability model

Application of the Two Nonzero component Lemma in Resource Allocation

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Journal of Applied Mathematics and Physics 2014年第7期2卷 653-661页

作者： Morteza Seddighin Mathematics Department Indiana University East Richmond IN USA

In this paper we will generalize the author's two nonzero component lemma to general self-reducing functions and utilize it to find closed from answers for some resource allocation problems.

关键词： Two Nonzero component Lemma Resource Allocation The Distribution of the Search Effort

Assessment of Environmental Carrying Capacity Using Principal component Analysis

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Journal of Geoscience and Environment Protection 2018年第3期6卷 54-65页

作者： Yinge Liu Junhui Zhang Shaoxiong Wang Yan Wang Aling Zhao Key Laboratory of Disaster Monitoring and Mechanism Simulating in Shaanxi Province College of Geography and Environment Baoji University of Arts and Sciences Baoji China

Regional environmental carrying capacity (ECC) is nonlinear and spatially specific. A hierarchy index system including resources, environmental and socio-economic elements was established using an analytic hierarchy process. Principal component analysis (PCA) was used to estimate the regional size and differences of environmental carrying capacities. Main information of four principal components, i.e., carrying capacity of resources supply, carrying capacity of environmental quality, carrying capacity of social economy and carrying capacity of infrastructure construction, was extracted. The ECC evaluation value was divided into five levels of lowest carrying capacity, low carrying capacity, medium carrying capacity, high carrying capacity and highest carrying capacity, respectively. The results showed that on the whole ECC was at the medium carrying capacity level. ECC was generally highest in Guanzhong plain, followed by Loess Plateau, and was lowest in Qiba mountain. The carrying capacity of water resources and environmental quality was relatively low, and the infrastructure carrying capacity was highest among the four components. The temporal spatial variation of ECC was closely related to vulnerability of the natural resources and environment in the regions. Verification was proven that PCA was a useful tool when applied to evaluate ECC and reflect the spatial distribution of large-quantity ECC indices on a large regional scale. This study provides a basis for comprehensive understanding of resources, environment and management for regional balanced development.

关键词： Environmental Carrying Capacity Principal component Analysis Spatial Dif-ference Evaluation of Indicators