数字电视机顶盒综述

在介绍数字电视机项盒的定义、功能及分类的基础上，着重探讨了数字电视机顶盒的软、硬件结构以及该产品的市场前景等问题。     

动态法研究啤酒花头香成份变化

啤酒花是一种重要的经济作物,本文研究其头香成份,对不同物候期的二种啤酒花头香成份的变化规律进行了动态研究。同时,研究了啤酒花品种之间头香成份的差异。     

佛手果头香挥发油的化学成分研究

用GC/MS/DS方法从佛手头香油中鉴定出29种化合物,其主要成分为柠檬烯,再用GC/FTIR方法进一步证实这一结论,其中有25种化合物在佛手油中过去没有报导过。     

HFC网功能的开发将产生宽带交互式新媒体

本文通过对有线电视ＨＦＣ频谱的分析和介绍其功能开发，并提出使计算机、通信、广播电视这三个原本分工明确的行业融合和会聚现象，又成为一个宽带交互式新媒体。     

一种更优的精度控制故障树解算方法

本文针对安全分析方法中故障树解算问题提出了一种完全依赖于所要求精度的近似算法——精度取舍法。详细给出了近似求解顶事件概率值的两个截断条件。结论表明，它在同时兼顾精度与时间的要求方面优于别的算法。     

Some recent theoretical progress in Higgs boson and top quark physics at hadron colliders

The test of the Standard Model and search for New Physics signal are main aim of LHC experiment. With the increasing of the measurement accuracy at the LHC, it is a major task in future to exceed the current accuracy of the theoretical predictions for important processes, in particular ones involving Higgs boson and top quark. In this review we briefly summarize some recent theoretical progress in Higgs boson and top quark physics, especially the fixed-order and resummation predictions in QCD at both the Tevatron and the LHC.     

齿轮孔径和键宽塞规CAD系统的开发

在国际著名的TopCAD平台上通过一次开发,完成齿轮内孔、健槽全系列塞规的柔性CAI）系统的设计,并结合上海机床齿轮厂的生产实际,完成中山复盛SA-3G系列压缩齿轮内孔、健槽全系列塞规的CAD系统开发,提高了塞规设计的自动化程度,提供了零件专用量具的计算机辅助设计的思路,具有系列化、智能化等特点。     

E级计算之远景

 超级计算机在当今科技发展中占有举足轻重的地位。在向着E级计算时代迈进之时,精确衡量超算的性能是一个事关超算架构和应用的关键问题。评价一台超算采用不同的基准会产生不同的结果。本文介绍超算中主要的3种排名及其对应的评测基准,并分析了超算本身的发展及应用远景。     

Analysis of Top Chinese Contractors’ Developmental Tracks and Evaluation of Their Strategic Selection of International Construction Markets

The past decade has witnessed a rapid development of the international construction market. This research aims to investigate top Chinese contractors＇ developmental tracks and evaluate their strategic selection of international construction markets over the period from 2001 to 2006, based on the modified Boston Consulting Group Matrix （BCG）. Results from 2001 to 2005 indicate that Asia and Africa, which were ＂question marks＂ markets for top Chinese contractors （abbreviated as TCCs） , have the most potential to become ＂stars＂ markets; other question marks markets such as the Middle East and Europe are found not to be of potential; ＂dogs＂ markets such as the U. S. , Canada and Latin America should be relinquished progressively unless there is renewed growth opportunity over the next two years. Compared to developmental tracks of top contractors from some advanced countries, TCCs＇ investment and development strategy in Africa seems to be sustainable and intensive ; TCCs＇ exit strategy for the Middle East appears deter- mined and swift, while their strategy in Asia seems to be lacking in persistence. Furthermore, the data of 2006 indicates that TCCs improve their performance in Asia and Africa, and Africa has become a ＂stars＂ market for TCCs. This research sheds important lights and insights into the prevailing process of internationalization of TCCs and provides a strategic direction for their selection of international construction market. What is more, this research is also valuable to other Chinese contractors who are seeking the opportunity to enter the international construction markets.     

车削细长轴科学夹紧方法的建议

针对细长轴车削加工的可靠性和安全性,受横向切削力产生弯矩,工件易变形等特点,加工时采取措施,设计倒锥工艺夹头,严格控制加工件的变形,从而保证加工精度。