世行贷款项目国内竞争性招标与国内项目公开招标的区别

结合世行贷款江苏省淮河流域重点平原洼地治理项目泰东河工程招标投标工作,对比分析世行贷款项目国内竞争性招标与国内项目公开招标两种方式,从招标过程中的各环节差异提出应重点关注的问题,为做好类似项目招标投标提供一定借鉴.     

EFFECT OF SUSPENDED SEDIMENT ON THE TRANSPORT AND TRANSFORMATION OF 4-NITROCHLOROBENZENE IN THE YELLOW RIVER

ＥＦＦＥＣＴＯＦＳＵＳＰＥＮＤＥＤＳＥＤＩＭＥＮＴＯＮＴＨＥＴＲＡＮＳＰＯＲＴＡＮＤＴＲＡＮＳＦＯＲＭＡＴＩＯＮＯＦ４－ＮＩＴＲＯＣＨＬＯＲＯＢＥＮＺＥＮＥＩＮＴＨＥＹＥＬＬＯＷＲＩＶＥＲ１ＳＨＥＮＸｉａｎｃｈｅｎ２ＡＢＳＴＲＡＣＴＡｓｉｍｕｌａｔｉ...     

火电厂循环水余热利用方式的研究

分析火电厂能源利用现状及冷源损失产生的原因,通过对低真空改造、循环水——水源热泵技术、机组NCB运行方式的比较分析,得出热泵供热技术具有更好的节能减排前景的结论,并揭示了火电厂降低循环冷却水冷源损失的发展趋势。     

基于NETBIOS的双机系统的设计与实现

双机设计是提高系统可靠性的一种方法。本文首先简要介绍了ＮＥＴＢＩＯＳ的概貌，网络控制块，命令和调用、接着论述了基于ＮＥＴＢＩＯＳ通信的双机系统的设计思想。特别地对会话创建，双机同步与故障判定，状态的切换与数据一致性的实现作了详细研究。     

基于NETBIOS的分布式仿真

文中阐述了网络基本输入输出系统的功能特点，它实现了网络工作之间点对点、点对多点的实时通信。在ＮＯＶＥＬＬ网络支持的ＷｉｎｄｏｗｓｏｆＷｏｒｋｇｒｏｕｐｓ环境中，有机地利用ＮＥＴＢＩＯＳ来实现分布仿真，提供图形用户接口，最后给出了部分仿真结果。     

开放式数控总线标准中数据链路层研究

在制定开放式数控系统总线接口与通信规范标准的基础上,针对数控系统的特点,提出一种基于抽象数据链路层和实际数据链路层的双子层数据链路层结构模型,讨论抽象数据链路层的服务和协议规范以及与实际数据链路层间的封装与映射机制,并实现应用层和实际数据链路层间的服务与协议转换。     

Cellulosic ethanol production: Landscape scale net carbon strongly affected by forest decision making

In producing cellulosic ethanol as a renewable biofuel from forest biomass, a tradeoff exists between the displacement of fossil fuel carbon (C) emissions by biofuels and the high rates of C storage in aggrading forest stands. To assess this tradeoff, the landscape area affected by feedstock harvest must be considered, which depends on numerous factors including forest productivity, the amount of forest in a fragmented landscape, and the willingness of forest landowners to sell timber as a bioenergy feedstock. We studied landscape scale net C balance by combining these considerations in a new, basic simulation model, CEBRAM, and applying it to a hypothetical landscape of short-rotation aspen forests in northern Michigan, USA. The model was parameterized for forest species, growth and ecosystem C storage, as well as landscape spatial patterns of forest cover in this region. To understand and parameterize forest owner decision making we surveyed 505 nonindustrial private forest (NIPF) owners in Michigan. Survey results indicated that 47% of these NIPF owners would willingly harvest forest biomass for bioenergy. Model results showed that at this rate the net C balance was 0.024 kg/m² for a cellulosic ethanol system without considering land use over a 40 year time horizon. When C storage in aggrading, nonparticipating NIPF land was included, net C balance was 1.09 kg/m² over 40 years. In this region, greater overall C gains can be realized through aspen forest aggradation than through the displacement of gasoline by cellulosic ethanol produced from forest biomass.     

正则化超声Lanczos反卷积的NCB成像分析

Lanczos方法是求解大尺度逆问题的一种有效方法,这种方法的特点是可以把大尺度问题转化为小尺度问题,而且可以把解严格限制在Krylov子空间,只是它存在的半收敛性问题需要进一步克服.为了确保算法的有效性、稳定性和精确性,Lanczos混合法(Lanczos-hybrid)试图通过正则参数的适当选取来解决这个问题.文章在Hansen提出的正则化参数选取的NCP方法基础上,设计了一种新的算法NCB,即利用Burg功率谱代替NCP中的经典周期图谱,较好地克服了Lanczos的半收敛性问题,降低了解对迭代次数的敏感性,得到了大尺度反卷积病态问题的稳定解;并以超声RF信号为例进行仿真,结果表明,NCB的成像效果比GCV要好.     

基于 Windows 下的网络实时通信技术

介绍了Ｗｉｎｄｏｗｓ系列操作系统（Ｗｉｎｄｏｗｓ３．１、ＷｉｎｄｏｗｓＮＴ及Ｗｉｎｄｏｗｓ９５中ＮｅｔＢＩＯＳ的体系结构，并分析了Ｗｉｎｄｏｗｓ操作系统中ＮｅｔＢＩＯＳ的实现方法，最后给出了Ｗｉｎｄｏｗｓ９５中的应用实例。