一种改进的十六进制文件管理工具—CHex32的研制

针对西方Hex32不能显示汉字和俄文具处理长文件时速度慢的问题，研制了一种改进的十六进制文件管理工具－CHex32，CHex32保留了西方Hex32对十六进制文件的主要编辑功以,胆一种用于分析软件功能和文件数据结构的实用工具。     

PVD涂层工艺在M3滚刀上的应用

对M3滚刀进行了物理气相沉积 (PVD)工艺试验。经高温耐磨试验和切削试验证明 ,M3滚刀经TiN涂层后 ,其耐磨性和使用寿命显著提高。     

飞秒激光烧蚀研究进展

介绍飞秒激光烧蚀材料的机理论模型，阐述飞秒激光烧蚀的特性，揭示飞秒激光烧蚀的广泛应用前景。     

讲个“把握重点”的故事

1977年4月间,台北天母地区有22栋5层楼的公寓住宅,在广告攻势展开的第4天,即开始接受订购。到了订购的第3天,即达成10O%的销售成绩。其立竿见影效果之高,销售速度之快,为众房地产商所瞩目。这批公寓住宅的投资兴建者是台湾信托投资公司。其特色是采取凹型设计,数幢房屋合围着一块百余坪的空地。将这块空地再设计成一座小花园,即形成数幢房屋合围着一片有百余坪的绿地花园,对住户而言,颇为理想。设计完成后,台湾信托就准备刊播广告进行销售。广告代理商经过多次会商确定广告战略:1、强调这是金融业所兴建销售的房屋。2、强调房屋具有别墅的…     

250W带功率因数校正整流电源模块的研制

功率因数校正技术越来越成为电源行业研究的热点。文中介绍了适用于雷达等设备的250W带功率因数校正整流电源模块的设计，分析了其中升压电感器设计、主开关管保护、控制电路消振、散热设计和表面贴装等关键技术，完成了实验研究，获得了满意的试验结果。     

S7-226PLC与MM440变频器在光缆护套机中的应用

本文介绍了由西门子S7—226PLC与MM440变频器组成的电气控制系统在光缆护套机速度控制中的应用。并对该系统的控制原理作了详细的阐述。     

Modeling of Temperature–Frequency Correlation Using Combined Principal Component Analysis and Support Vector Regression Technique

A good understanding of environmental effects on structural modal properties is essential for reliable performance of vibration-based damage diagnosis methods. In this paper, a method of combining principal component analysis (PCA) and support vector regression (SVR) technique is proposed for modeling temperature-caused variability of modal frequencies for structures instrumented with long-term monitoring systems. PCA is first applied to extract principal components from the measured temperatures for dimensionality reduction. The predominant feature vectors in conjunction with the measured modal frequencies are then fed into a support vector algorithm to formulate regression models that may take into account thermal inertia effect. The research is focused on proper selection of the hyperparameters to obtain SVR models with good generalization performance. A grid search method with cross validation and a heuristic method are utilized for determining the optimal values of SVR hyperparameters. The proposed method is compared with the method directly using measurement data to train SVR models and the multivariate linear regression (MLR) method through the use of long-term measurement data from a cable-stayed bridge. It is shown that PCA-compressed features make the training and validation of SVR models more efficient in both model accuracy and computational costs, and the formulated SVR model performs much better than the MLR model in generalization performance. When continuously measured data is available, the SVR model formulated taking into account thermal inertia effect can achieve more accurate prediction than that without considering thermal inertia effect.     

Resource contention in shared-memory multiprocessors: A parameterized performance degradation model

A standard metric conventionally employed to compare the performance of different multiprocessor systems is speedup. Although providing a measure of the improvement in execution speed achievable on a system, this metric does not yield any insight into the factors responsible for limiting the potential improvement in speed. This paper studies the performance degradation in shared-memory multiprocessors as a result of contention for shared-memory resources. A replicate workload framework with a flexible mechanism for workload specification is proposed for measuring performance. Two normalized performance metrics—efficiency and overhead factor—are introduced to quantify the factors limiting performance and facilitate comparison across architectures. Finally, the proposed model is employed to measure and compare the performance of three contemporary shared-memory systems, with special emphasis on the newly released BBN Butterfly-II (TC2000), currently undergoing Beta test.     

一种性能可调的新型节能材料－电致变色膜

本文介绍了一种性能可调的新型节能材料—电致色薄膜，描述了以其为核心的全固态灵巧窗结构、工作原理和光学调节性能，回顾了电致色材料、离子存储层和固态锂离子导体及其性质，并展望了这种新型节能材料的应用。