基于SSM框架的大坝监测数据管理系统设计

针对目前大坝安全监测存在数据不能实时计算分析、展示,长期运行产生的大量数据主要靠人工整编且易出错等问题,结合现代信息化技术手段,以Java作为服务开发语言,设计了基于Spring+SpringMVC+Mybatis(SSM)框架的大坝安全监测数据管理平台,用于大坝监测数据的管理和分析,实现数据采集、存储、查询、计算分析、绘图、生成报表报告、实时监控及远程展示等功能,同时亦为监测仪器管理提供了可视化界面,方便仪器管理。结果表明,基于SSM框架的大坝安全监测数据管理系统实时反馈效果好,操作便捷,数据存取性能好、可视化程度高,便于大坝监测数据的管理与实时分析,为大坝安全运行与决策提供支撑。     

一次法混炼胶在半部件工序中的应用

通过一次法混炼(SSM)混炼胶在轮胎半部件各工序的使用,从流动性、膨胀系数、生热等方面,详细阐述了SSM混炼胶在使用性能上与普通混炼胶的差异。现场实践及数据收集和分析表明:SSM胶料在压出时胶料呈现出的膨胀率小,尺寸前后波动小;拉断强度、定伸强度大。SSM混炼胶混炼时对分子间力破坏小,门尼黏度高但是流动性好,胶料性能稳定,且生热较低。     

中国资源型城市产业结构演进分析

自“十六大”提出资源型城市转型以来,资源型城市的产业结构发生了哪些变化？在概述了国内学者关于资源型城市产业转型相关研究的基础上,得到学者对资源型城市产业结构总体变化的研究较少。应用产业结构变化率,研究了资源型产业结构变化特征;应用产业结构偏离度,研究了产业结构协调性;偏离-份额分析了引起产业结构变化的原因。通过以上分析方法得到：资源型城市产业结〖JP2〗构变动幅度强于全国,个体变动差异明显;产业协调性优于全国,但需要协调的产业不同;10年(1999-2008年)来资源型城市的经济增长主要由产业结构转移份额和全国增长份额贡献,区域竞争力份额有待提高;全国增长份额在东-中-西部资源型城市中表现出“3-2-1”的倍数递减效应;产业结构转移份额是引起资源型城市经济增长的主要驱动力,第二产业显著地促进了经济增长;资源型城市区域竞争力有待提高,急需注重竞争力的培育;注重朝阳产业培育的资源型城市经济增长速度均较快,产业结构调整不力的资源型城市发展缓慢。     

开绕组无刷双馈发电机直接功率控制研究

针对开绕组无刷双馈电机模型复杂且耦合性强的问题,提出一种适用于开绕组无刷双馈电机的新型直接功率控制方法。通过研究定子控制绕组侧电压与功率绕组侧有功功率和无功功率间的关系,推导出基于d-q坐标系的直接功率控制状态方程,实现有功和无功功率的解耦控制。针对传统滑模控制器抖振及不连续高频开关控制等缺点,设计了基于新型趋近律的超扭曲滑模控制器,建立了开绕组无刷双馈发电机新型超扭曲滑模直接功率控制系统的仿真模型,并给出了不同工况下的仿真结果,验证了该功率方程模型的正确性和新型超扭曲滑模控制方法的有效性和鲁棒性。     

可扩展SSM协议的设计与仿真

指定信源域间组播SSM主要是为了解决域间组播地址变化问题而提出的,它有效地解决了ASM域间组播路由的复杂性,并具有更好的会话完整性和安全性,但仍然面临严重的状态可扩展性问题.分析了SSM中的可扩展性问题,在此基础上就SSM中转发状态的可扩展性问题,提出了一种采用分枝节点算法的改进的SSM协议,可以提高SSM协议的可扩展性,描述了工作原理,并基于NS-2进行了性能评估.     

基于NS-2的特定源组播仿真研究与实现

作为一种新的组播模型,特定源组播受到学术界越来越多地关注.它解决了传统IP组播组地址冲突、缺乏访问控制等问题,适于单源组播的应用.仿真实验是一种经济有效的网络技术研究方法.NS-2是目前应用较为广泛的网络仿真平台,支持各种网络协议仿真,但是并不支持特定源组播.为此,分析了使用NS-2进行IP组播模拟的实现原理,通过扩展NS-2实现SSM协议的仿真实验.模拟结果显示该仿真实现与SSM的规范相一致.     

A comparison of 18 winter seasons of in situ and passive microwave-derived snow water equivalent estimates in Western Canada

The Meteorological Service of Canada (MSC) has developed an operational snow water equivalent (SWE) retrieval algorithm suite for western Canada that can be applied to both Scanning Multichannel Microwave Radiometer (SMMR) and Special Sensor Microwave/Imager (SSM/I) data. Separate algorithms derive SWE for open environments, deciduous, coniferous, and sparse forest cover. A final SWE value represents the area-weighted average based on the proportional land cover within each pixel. The combined SSM/I and SMMR time series of dual polarized, multichannel, spaceborne passive microwave brightness temperatures extends back to 1978, providing a lengthy time series for algorithm assessment. In this study, 5-day average (pentad) passive microwave-derived SWE imagery for 18 winter seasons (December, January, February 1978/79 through 1995/96) was compared to SWE estimates taken from a distributed network of surface measurements throughout western Canada.Results indicated both vegetative and snowpack controls on the performance of MSC algorithms. In regions of open and low-density forest cover, the in situ and passive microwave SWE data exhibited both strong agreement and similar levels of interannual variability. In locations where winter season SWE typically exceeded 75 mm, and/or dense vegetative cover was present, dataset agreement weakened appreciably, with little interannual variability in the passive microwave SWE retrievals. These results have important implications for extending the SWE monitoring capability of the MSC algorithm suite to northern regions such as the Mackenzie River basin.     

组管理协议IGMPv3分析

因特网组管理协议的主要目的是在一个子网内，为主机和路由器提供必要的信息交互，以帮助主机动态地加入和离开某个特定的组播组。组管理协议最新的版本为IGMPv3。2002年在RFC 3376“Intemet Group Management Protocol，Version 3”中定义。     

广东电力数字同步网规划研究及应用

电力数字同步网电电力专用通信网的一个必不可少的重要组成部分,能准确地将同步信息从基准时钟向同步网元传递,以保证传输电力高精度数据信息,特别ＳＤＨ技术的广泛应用,对时钟技术提出新的要求,文中就广东电力数字同步网规划（一期）,特别是结合广东电力ＳＤＨ通信网的建设,论述数字同步网规划及实际应用。     

Towards the appropriate human-centred information systems: A case study of the Japanese retail industry

The industries of Japan have developed by learning from Western industries, especially the USA, and by implementing many of their concepts and technologies. However, Japanese industries have often implemented these concepts and technologies in a very different way from the USA. For example, while the USA uses information systems in retail industries as a tool by which data are collected and analysed to control the market, in Japan this same technology is considered rather as a learning device to interpret the market. While in the USA the market is seen as a natural phenomenon capable of being controlled, the Japanese see it as an ambiguous phenomenon that is ever changing and is not capable of being controlled. Rather it is important to feel the change in the market itself.This paper introduces human centredness to the information system, and argues against modern rationalism, i.e. human versus technology, taking the case of use of POS data from the POS system (point of sale: a system that collects data on both the customer and goods sold by scanning bar codes that are attached to the surface of the goods) by the eminent Japanese retailer, Ito-Yokado. It emphasises an interactive concept of interaction between human and technology of the postmodern paradigm.