Suitability evaluation of urban construction land based on geo-environmental factors of Hangzhou, China

Suitability evaluation of urban construction land based on geo-environmental factors is the process of determining the fitness of a given tract of land for construction. This process involves a consideration of the geomorphology, geology, engineering geology, geological hazards, and other geological factors and is the basis of urban construction land planning and management. With the support of Geographic Information Systems (GIS), grid analysis, and geo-spatial analysis techniques, four factor groups comprising nine separate subfactors of geo-environmental attributes were selected to be used in the evaluation of the suitability level for construction land in Hangzhou. This was based on K-means clustering and back-propagation (BP) neural network methods due to their advantages in fast computing, unique adaptive capacity, and self-organization. Simultaneously, the evaluation results based on K-means clustering and BP neural network were compared and analyzed, and the accuracy evaluation was set. The results showed that the geo-environmental suitability evaluation results of construction land based on K-means clustering and BP neural network were similar in terms of the distribution and scale of construction land suitability level. At the same time, the results of the two evaluation methods were consistent with the variability in suitability level, engineering geology, and hydrogeology of Hangzhou. The results also showed that the real advantage of the methods proposed in this paper lies in their capacity to streamline the mapping process and to ensure that the results are consistent throughout. The suitability level of the urban construction land based on the geo-environment in Hangzhou was divided into four construction sites: land for building super high-rise and high-rise buildings, land for building multistorey buildings, land for low-rise buildings, and nonbuilding land. The results of the suitability evaluation for each category will provide a scientific basis for decision-making in urban development in Hangzhou.     

BSPNN: boosted subspace probabilistic neural network for email security

In the modern age of Internet connectivity, advanced information systems have accumulated huge volumes of data. Such fast growing, tremendous amount of data, collected and stored in large databases has far exceeded our human ability to comprehend without proper tools. There has been a great deal of research conducted to explore the potential applications of Machine Learning technologies in Security Informatics. This article studies the Network Security Detection problems in which predictive models are constructed to detect network security breaches such as spamming. Due to overwhelming volume of data, complexity and dynamics of computer networks and evolving cyber threats, current security systems suffer limited performance with low detection accuracy and high number of false alarms. To address such performance issues, a novel Machine Learning algorithm, namely Boosted Subspace Probabilistic Neural Network (BSPNN), has been proposed which combines a Radial Basis Function Neural Network with an innovative diversity-based ensemble learning framework. Extensive empirical analyses suggested that BSPNN achieved high detection accuracy with relatively small computational complexity compared with other conventional detection methods.     

PLC在高浓度冲稀自动控制系统的应用

本文在介绍高浓度冲稀自动控制系统的工作原理、特点、系统调校及日常维护要点的基础上,探讨了PLC在这种类型的系统中的应用。     

一个基于CORBA和Java技术的分布式并行有限元计算环境

该文结合ＣＯＲＢＡ（Ｃｏｍｍｏｎ Ｏｂｊｅｃｔ Ｂｒｏｋｅｒ Ａｒｃｈｉｔｅｃｔｕｒｅ）和Ｊａｖａ技术,提出了一个能在支持ＴＣＰ／ＩＰ协议的异构网络环境下实现分布式有限元计算环境的具体方案,为了验证方案的可行性,在西南交通大学应用力学与工程系计算中心的局域网上实现了分布式并行计算环境的基本框架,并进行了１０００阶矩阵相乘的计算。     

基于SuperMap IS技术的Web GIS实现

探讨利用SuperMap IS技术构造Web GIS的方法,以及在此基础之上如何利用SuperMap IS提供给用户的客户端开发模版进行Web GIS开发.     

直面价格战,期盼监管新举措

首先描述了当前我国电信市场上价格大战的种种现象，剖析了价格战对固网市场产生的强烈影响和冲击。指出应对价格战急需政府加强监管力度，最后提出了政府加强监管的政策性建议。     

Electrically induced heat dissipation in metallized film capacitors

Elevated temperature is a key aging factor for metallized polymer film capacitors with the capacitor life expectancy halved with every 8/spl deg/C of temperature rise. For film capacitors in service, both application of a time-varying external voltage and the extinction of internal breakdown events can deposit significant heat onto the capacitor structure leading to an undesirable temperature rise. Often such heat generation is localized spatially and the resulting temperature gradient enhances the probability of subsequent breakdowns. To facilitate a thorough and generic understanding, a thermal model of metallized film capacitors is developed to simulate the dynamics of heat generation and transfer under the switching impact of an external voltage. Thermal processes in solids (polymer layers, electrode coating, and zinc-spray segment) are modeled with conduction mechanism, whereas convection mechanism is considered for silicone oil and air. Heat generation is induced either by ohmic losses of the externally applied electric field, or by internal breakdown events within the metallized film capacitor structure. This allows a seamless interface between the heat transfer model and the equivalent circuit based field calculation model. Based this electrothermal model, numerical examples are used to study temperature distribution within film capacitors and then to examine the likelihood of localized temperature hot-spots that may lead to spatially preferential breakdowns.     

国家烟草专卖局现行职能缺陷刍议

2008年,国务院国家烟草专卖局调整为工业和信息化部管理的副部级国家局.这次调整对国家烟草专卖局的职责有所优化,但并未能根本触动"政企合一"的体制,缺陷明显,政策制定和贯彻落实时有冲突.