Distributed architecture for energy management D-structure

Electric power systems are expanding in size and complexity, and the requirement for the energy management system (EMS) is becoming more important. In this computer control system, a single control computer is used mainly as the primary computer and its software is very complicated because of its hugh number of small, quick tasks to obtain high response speed. Therefore, much effort is needed to develop and modify the programs, and the responsiveness of this centralized architecture varies greatly when many faults occur in the power system. This paper describes a new distributed architecture for the EMS. Distributed processors execute the functions cooperatively with periodic access to the common bulletin board database in which information about the power system exist. This architecture facilitates the software development and maintenance, and it also enhances the performance by the parallel processing of the distributed functions.     

A simplified cascade current‐source inverter interconnected to a single‐phase three‐wire distribution system and its application to electric energy storage systems with batteries

A novel current source inverter system interconnected to the single‐phase grid is proposed. It has the same construction as the conventional three‐phase current source inverter that is interconnected to the single‐phase three‐wire distribution system. Though the proposed circuit has no output transformer, it can be equivalently performed as the single‐phase double cascade inverter by diverting the pole transformer in the utility system. By controlling the appropriate scheme, the output currents can be obtained as the five‐level waveforms and their distortions can be decreased sufficiently. It is applied to the interactive electric energy storage system with batteries and the basic discharging characteristics are discussed experimentally. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 150(2): 50–61, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10380     

北京城市供水安全及对策研究

“十一五”期间是首都经济社会快速发展的关键时期，也是应对水资源紧缺、保障供水安全的关键时期。确保首都供水安全是北京水务工作的第一要务，北京市水务局针对城市供水存在的主要矛盾和问题，对城市供水水源、水质水量、水厂、管网、设施等情况进行了全面调查，确定了工作思路，并据此提出了保障城市供水安全的目标和措施。     

Characteristics and classification of high-current fault arcs on distribution systems

When a fault occurs on transmission or distribution systems due to lightning or overvoltage, often an arc discharge occurs at the fault point. The arc discharge, which is caused by a fault current, has a high current, high temperature, strong light emission, etc., thus it sometimes causes heavy damages to electric power equipment. The arc discharge is influenced by the conditions around the arcs, i.e., gas, insulation materials, gap length, weather, etc. Also, the arc voltage along the arc column indicates the characteristics of the arc. If the voltage waveforms of the arcs caused by the fault on transmission or distribution systems are classified, it is possible to find the location and the equipment where the fault occurred. In this paper, the arc voltage data in 6-kV class XLPE cables and 6-kV class overhead lines are analyzed and an artificial neural network method is applied to classify the arc voltage waveforms. The results obtained from the six artificial neural networks developed show that the artificial neural network method is effective for classification of arc voltage waveforms if adequate input parameters are selected.     

Identification environment and robust forecasting for nonlinear time series

In this paper, the methods of time series for nonlinearity are briefly surveyed, with particular attention paid to a new test design based on a neural network specification. The proposed integrated expert system contains two main components: an identification environment and a robust forecasting design. The identification environment can be viewed as a integrated dynamic design in which cognitive capabilities arise as a direct consequence of their self-organizational properties. The integrated framework used for discussing the similarities and differences in the nonlinear time series behavior is presented. Moreover, its performance in prediction proves to be superior than the former work. For the investigation of robust forecasting, we perform a simulation study to demonstrate the applicability and the forecasting performance.     

开发计算机管理信息系统推动设备供应管理现代化

本文介绍了我国冶金大型钢铁联合企业设备供应管理系统计算机应用开发过程及研制方法，并分析了取得的经济效益和在国内的推广价值。     

Huffman algebras for independent random variables

Based on a rearrangement inequality by Hardy, Littlewood, and Polya, we define two-operator algebras for independent random variables. These algebras are called Huffman algebras since the Huffman algorithm on these algebras produces an optimal binary tree that minimizes the weighted lengths of leaves. Many examples of such algebras are given. For the case with random weights of the leaves, we prove the optimality of the tree constructed by the power-of-2 rule, i.e., the Huffman algorithm assuming identical weights, when the weights of the leaves are independent and identically distributed.     

基于一种混合的节点定位算法的研究

针对基本的DV-Hop节点定位算法会产生不良的节点和多级跳带来的累积误差以及未知节点的坐标没有进行修正等缺点,提出了一种改进的混合节点定位算法WHDV-Hop算法,改进后的算法定位误差率明显比改进前的定位误差率小,通过MATLAB软件对节点定位误差方面进行仿真验证,仿真实验结果证明该改进后的算法稳定、可靠,易于实现。与DV-Hop算法相比,定位精确度提高了4.65%,计算量减少,降低了能量消耗水平,实现预期的目标。     

Volume functions of historical texts and the amplitude correlation principle

A new empirico-statistical model is suggested to distinguish dependent narrative texts from independent narrative texts by means of their volume functions. A regard for information principle and an amplitude correlation principle are formulated. The model and both principles are examined experimentally using specific historical texts.Anatoliy T. Fomenko (Dr. Sci. in mathematics, Lomonosov State University) is a Professor at Lomonosov State University, Moscow. He is author of twelve monographs and textbooks, and is co-author of the two-volume Modern Geometry (Springer-Verlag). He is also artist and historian.Svetlozar T. Rachev (Dr. Sci., Steklov Mathematical Institute) is a Professor at the University of California, Santa Barbara. He has published more than seventy papers and is co-author of the monographMathematical Models for Construction of Queuing Models (Moscow, 1988). His main interests are: stability of stochastic models, theory of probability metrics, queuing theory and survival models.     

AES算法的硬件实现分析与设计

分析了AES算法的结构特点,对算法的不同硬件实现方式进行了对比分析,分析结果表明,不同的实现方式在算法应用模式支持、运行频率、资源占用、吞吐量方面各有优缺点,需要根据具体应用需求采用合适的实现方式。对AES算法不同实现方式的分析以及提出的设计结构对于其他类似的分组密码算法实现也具有参考价值。