Synthesis,characterization and side chains crystallization of comb-like poly(<Emphasis Type="Italic">p</Emphasis>-<Emphasis Type="Italic">n</Emphasis>-alkylstyrene)s

A series of comb like poly(p-n-alkylstyrene)s with linear alkyl groups, containing even numbers of carbon atoms from 12 up to 22 were synthesized by radical polymerization and characterized by FTIR, ¹H NMR, TGA, TVA DSC, and WAXS. All polymers were obtained in good yields and were soluble in organic solvents as chloroform, dichloromethane or tetrahydrofuran and insoluble in methanol; they are stable up to temperatures near 300 °C. On the other hand, the alkylic side chains of all series are able to crystallize in a paraffinic phase in which the melting temperature and enthalpy increase with the methylene number of the n-alkyl chain.     

Key project management practices affecting Singaporean firms’ project performance in China

Foreign (non-mainland Chinese) architectural, engineering and construction (AEC) firms may face difficulties managing construction projects in China because they are unfamiliar with this new operating environment. This study investigates project management (PM) practices adopted by Singaporean AEC firms in China. It determines the performance level of their projects in China; identifies PM practices that led to better performance; and recommends key PM practices that could be adopted by foreign AEC firms in China to achieve project success. A structured questionnaire was designed and data were collected via a self-administered postal and email survey, targeting Singaporean AEC firms that had undertaken and managed projects in China. The study finds that certain PM practices do indeed affect project performance. The most important of these are practices relating to scope management, such as controlling the quality of the contract document, quality of response to perceived variations and extent of changes to the contract. It is recommended that foreign firms adopt some of the PM practices highlighted in this study to help them achieve better project performance in China.     

LED驱动器的优化设计

本文在分析目前LED驱动器存在的一些问题的基础上，以Intersil公司高功率LED驱动器ISL78100为例，说明了LED驱动器应用中应考虑的一些设计参数，包括电路结构以及元器件的选择等，最后提出了有效解决功耗和系统可靠性问题的方法。     

基于Salvo的嵌入式直流伺服电机控制系统

本文探讨一种采用中低档微处理器的嵌入式直流伺服电机控制系统,该系统用户软件设计采用嵌入式实时操作系统Salvo,系统功能扩展和裁剪方便,可移植到各个应用领域。     

Testing Driver Skill for High-Speed Autonomous Vehicles

The 2005 DARPA Grand Challenge, a 212-kilometer race through the Mojave Desert, showcased the state of the art in high-speed, autonomous navigation of trails and roads. To win the challenge, a team's robot had to complete the course faster than any other robot, and it had to do so within 10 hours. Carnegie Mellon University's Red Team developed two robots, which used a combination of autonomous and human preplanning to become two of only four robots to complete the Grand Challenge. The robots used onboard sensors to adjust a preplanned route to avoid obstacles and correct for position-estimation errors. To be successful, teams had to develop innovative algorithms and systems - and rigorously test them to verify performance. The Red Team used the tests regressively to evaluate how unit changes in hardware and software affected the robots' overall driving ability     

Adjuvant chemotherapy for patients with resected Dukes' C and high-risk B2 colon cancer with fluorouracil and levamisole

Carcinoma of the large bowel is the second leading cause of cancer mortality in Singapore. Although the great majority of patients are discovered at a stage where resection with curative intent is possible, almost half of the patients afflicted will die of it. The combination of 5-fluorouracil + levamisole used in patients with curatively resected high risk Dukes B2 and all Dukes' C colon cancers has been shown to reduce cancer recurrence rate and improve overall survival. Since 1990 adjuvant chemotherapy has been recommended for this group of patients. This report describes patients treated in Singapore, their toxicities and their outcome. A total of 341 patients were treated between 1990 and 1996. Treatment compliance was 71.8%. Toxicity was moderate with mainly grade 1-2 nausea and vomiting, diarrhoea, stomatitis, alopecia, and neutropenia. There was 1 treatment-related death. Median recurrence-free interval was 81 months and median survival was not reached at 90 months. This regimen is tolerable. Until further randomised reports comparing 5-fluorouracil + levamisole to other combinations are available, this combination chemotherapy is recommended to patients after surgical resection of the high risk Dukes' B2 and Dukes' C colon cancer to reduce cancer recurrence and improve overall survival.     

PREDICTOL: a computer program to determine the thermophysiological duration limited exposures in various climatic conditions

PREDICTOL is a PC program used to determine the thermophysiological duration limited exposures (DLE) in humans, nude or clothed, submitted to various climatic conditions (hot and cold climates) at rest or during a physical exercise. DLE are determined following different standards of the International Standardization Organization (ISO), especially ISO 7933 for hot environment and ISO-TR 11079 for cold environment. The original aspect of this program is that it can be used whatever the climatic conditions. The program presents two modes: an educational interactive mode and a scenario mode. The educational interactive mode demonstrates the thermophysiological effects, expressed as DLE, of different parameter changes (temperature, humidity, wind speed, metabolic heat production by physical exercise, clothing insulation and water vapor permeability). The scenario mode determines DLE for given various linked sequences as encountered in occupational, military or even recreational activities, each sequence being characterized by its climatic conditions, physical activities performed and by physical clothing properties. DLE given by PREDICTOL are correlated to those obtained in various controlled climatic laboratory conditions (r = 0.86; P < 0.001). PREDICTOL is written in Visual Basic 6.0. A "help menu" is provided to explain the use of the program and give information concerning the equations used to calculate both the thermal balance and DLE.     

CAutoCSD – Evolutionary Search and Optimisation Enabled Computer Automated Control System Design

This paper attempts to set a unified scene for various linear time-invariant (LTI) control system design schemes, by transforming the existing concept of "computer-aided control system design" (CACSD) to novel "computer-automated control system design" (CAutoCSD). The first step towards this goal is to accommodate, under practical constraints, various design objectives that are desirable in both time and frequency domains. Such performance-prioritised unification is aimed at relieving practising engineers from having to select a particular control scheme and from sacrificing certain performance goals resulting from pre-commitment to such schemes. With recent progress in evolutionary computing based extra-numeric, multi-criterion search and optimisation techniques, such unification of LTI control schemes becomes feasible, analytical and practical, and the resultant designs can be creative. The techniques developed are applied to, and illustrated by, three design problems. The unified approach automatically provides an integrator for zero-steady state error in velocity control of a DC motor, and meets multiple objectives in the design of an LTI controller for a non-minimum phase plant and offers a high-performance LTI controller network for a non-linear chemical process.