ARTIFICIAL NEURAL NETWORKS FOR CONSTRUCTION BID DECISIONS

An Artificial Neural Network (ANN) approach was explored for supporting construction bid decisions, since such decisions are heavily dependent on practitioner expertise, which in turn is generally encapsulated in case histories. One of the ANNs described here was trained on knowledge from a sample of the entire Sri Lankan construction industry, and was used to predict the preferred job sizes for firms of differing characteristics; such information could help firms in their bid/no-bid decisions. The other ANN was trained on case histories elicited from a single contractor, and was used to predict the percentage mark-up. The network outputs were obtained in both binary output and continuous valued output formats. The former format had some distinct advantages over the latter, as it provided greater information for decision making instead of being a “black box” output. The influences of the middle layer size, output format and allowable error during training, on the training duration and accuracy of prediction were studied.     

Multi-dimensional Evaluation of Recent Neighbourhood Renewal Projects in Beijing: Case Studies on Shichahai and Jinyuchi Neighbourhoods

Most of Chinese cities have experienced a great wave of large-scale neighbourhood renewal in recent years. However, only a few research works have been done in giving assessment after the completion of renewal projects. Aimed at such a circumstance, this paper, by referencing the experience of European countries, establishes a multi-dimensional evaluation framework to analyze the primary data drawn from recent household surveys of Shichahai and Jinyuchi neighbourhoods in Beijing, and puts forward some suggestions based on the conclusions drawn from the surveys.     

Old-age Care Modes and Facility Planning Based on the Concept of “Continuum of Care”

Through the comparative analysis on the theories and practical experience of the development of old-age care (OAC) in both China and other countries,and based on the interview and questionnaire survey in Zhejiang Province and Hangzhou City,this paper proposes the research and analysis framework for the old-age service system,i.e.,"OAC mode-OAC service system-OAC facility system." The paper argues that,oriented by OAC mode of "taking community-and home-based care as the main body and institution-based care as supplement," China should build an OAC facility system and planning thoughts that take "continuum of care" as concept and long-term care system as core.Taking Zhejiang Province and Hangzhou City as examples,the paper conducts the optimization research on current OAC facilities planning in terms of hierarchical system,scale,and differentiation,so as to formulate more systematic and operable planning standards for OAC facilities.     

基于网络环境的可转位球头立铣刀CAD系统的设计与实现

针对可转位球头立铣刀的结构特点,设计出一套基于网络环境的CAD系统。阐述了系统三层B/S结构设计框架和设计流程,探讨了系统所采用的关键技术及实现细节。本系统可为其他同类产品的网络化开发和商业化应用提供借鉴。     

前馈电路的性能分析

本文运用Volterra级数分析了采用前馈技术,使微波功率放大器线性改善的程度。给出前馈电路实验结果。     

音乐信号自适应加重网络增量调制的理论与实现

本文分析了音乐信号自适应加重网络增量调制(ΔM)的原理和适用性,从理论上推导了自适应加重网络的传递函数表达式,且描绘了音乐信号的加重曲线,并得出了在工作频率为3KHz可提高信噪比约7dB的结论。在文章的最后给出了整个自适应加重网络实现的具体框图和部分电路。     

脉冲波形的微分变换

本文叙述的脉冲波形微分变换,是一种专门用于某些脉冲波形在t—u坐标系和u-du/dt坐标系之间实现数学变换的方法。其目的主要在于准确求出不规则电脉冲随幅度变化的速率变化。文中介绍了几种常用的数学函数的微分变换,以及实现这种变换所用的微分器和实验装置,在双踪示波器屏幕上能够显示出速率变化图形。这种图形,在医学上对研究肌肉和神经电脉冲是非常有用的。     

固流体波面板换热器振动强化传热的研究

研究了波面板换热器在振动情况下的传热特性。通过研究发现，振动床传热模型可以用两区模型来表示，振动床的传热系数高于同类情况下移动床的传热系数。这为固流体波面板换热器强化传热的研究与开发提供了一条途径。     

花瓣形翅片管的强化传热研究概况

综述了花瓣形翅片管在低表面张力介质及其混合物中的冷凝强化传热、含不凝性气体水蒸气的冷凝强化传热以及空气和油的冷却强化传热等方面的研究概况、进展、成果及其工业应用前景。