B/S模式应用系统的一种新型结构及其实现

由于目前Ｂ／Ｓ模式应用系统的缺陷,提出了一种新型的系统结构并从原理上阐述了它的合理性,最后从模块间的通信。处理线程和数据库操作程间的同步和互斥以及系统等方面讲述系统的实现。     

平面内一组线段的可见性

给定平面内一组互不相交的线段,本文讨论其相对于某点的可见性,给出了时间复杂性为O(mlogm)的算法,并证明了这一算法在时间上是最优的.     

Performance evaluation of a dental handpiece in simulation of clinical finishing using a novel 2DOF in vitro apparatus

This paper reports on the performance evaluation of a dental handpiece in simulation of clinical finishing using a novel two-degrees-of-freedom (2DOF) in vitro apparatus. The instrumented apparatus consisted of a two-dimensional computer-controlled coordinate worktable carrying a dental handpiece, a piezoelectric force dynamometer, and a high-speed data acquisition and signal conditioning system for simulating the clinical operations and monitoring the dental finishing processes. The performance of the dental handpiece was experimentally evaluated with respect to rotational speed, torque, and specific finishing energy under the applied clinical finishing conditions. The results show that the rotational speeds of the dental handpiece decreased by increasing either the depth of cut or the feed rate at a constant clinically applied air pressure and water flowrate. They also decreased when increasing both the tangential and normal finishing forces. The specific finishing energy decreased with an increase in either depth of cut or feed rate, while the finishing torque increased as either the depth of cut or the feed rate was increased. Implications of these results were to provide guidance for proper applications of dental handpieces in clinical practice.     

1000BASE—T—在5类铜缆上实现千兆传输

１０００ＢＡＳＥ－Ｔ是一种在５类铜缆上传输１０００Ｍｂｐｓ速度的以太网解决方案。本文介绍了１０００ＢＡＳＥ－Ｔ的基本特性、关键性能参数及其设计。     

金属粉末注射成形粘结剂的发展

概括了金属注射成形粘结剂的功能与发展过程，并对几种典型粘结剂及其脱除工艺进行了适用性与经济性分析。     

DY型风口特性及其在局部空调中的应用

介绍了ＤＹ型风口的结构及射流特性。通过理论分析给出了风口速度衰减的经验公式，介绍了局部空调的定义及ＤＹ型风口在局部空调中的应用实例。     

Effect of Ion Dose on Growth of Relaxed SiGe Layer on Ion Implantation Si Substrate

Thin strain-relaxed Si0.8Ge0.2 films (57.6 nm) on the 30 keV Ar ion implantation Si substrates for different dose (1 × 1014, 5 × 1014, 3 × 1015 cm-2) were grown by ultra high vacuum chemical vapor deposition (UHVCVD) system.Rutherford backscattering/ion channeling (RBS/C), high resolution X-ray diffraction (HRXRD), Raman spectra as well as atomic force microscopy (AFM) were used to characterize these SiGe films. Investigations by RBS/C as well as HRXRD demonstrate that these thin Sio.8Geo.2 films could indeed epitaxially grow on the Ar ion implantation Si substrates. Under low dose ( 1 × 1014 cm-2) and medium dose (5 × 1014 cm-2) implantation conditions, the relaxation extents of SiGe films are 60.6% and 63.6%, respectively. However, high dose implantation (3 × 1015 cm-2) prompt the strain in epitaxial SiGe film to be close to full relaxation status (relaxation extent of 96.6% ). On the other hand, determinations of RBS/C also indicate the crystalline quality of SiGe film grown on high dose implantation Si substrate is nearly identical to that grown on low dose (1 × 1014 cm-2) implantation Si substrate.