中子发生器检测仪

一种采用单片微机控制的能谱，时间谱采集处理系统。该系统可对国产及进口的中子发生器主要性能进行室内检测，包括中子管气压工作状态监测，脉冲占子到达时间谱能量，产额指示，高压监测等，时间谱及ＴＴＬＣ数据可打印或绘成曲线输出。该检测仪已在现场取得良好的使用效果，现场反映仪器性能可靠，使用简便，时间谱曲线与３７００系统大车测量结果非常吻合，给检修，维护提供了极大地方便。     

储能式印字机构的磁系统与动态特性

储能式点阵针式打印机因有很多优点而受到越来越多的关注,但对其印字机构的理论分析计算方面的文献还较少。本文注意到该机构磁系统具有永久磁铁的特点,提出一种较简易的方法,解决其磁路计算问题,并阐述击打件动态特性的分析。最后,对一实际机构进行了计算,获得该机构一系列参数的数值。其结果可用来评价这种印字机构磁系统与印字条件的技术性能。上述方法适用于同类型印字机构的分析计算。     

Dreamweaver中的页面跳转

Dreamweaver是目前在网站开发中使用最为广泛的一种软件，因其所见即所得的使用方式而大受欢迎。在网页中添加链接是必不可少的，本文就在网页制作过程中会遇到的两种常见难题给出方法以解答之。     

在PB中调用Delphi图像处理程序实现旋转打印

指出了PB本身不具备旋转打印功能的弱点 ,提出了借助具有图像处理功能的其它语言实现证件打印的旋转要求的设计思想。还给出了证件页格式分析 ,中间文件符号约定 ,以及Del phi智能旋打程序。     

高级小字库技术

本文介绍了一些小字库的高级技术，包括静态排序、对分搜索、动态维护、驻留ＶＲＡＭ等。应用这些技术可大大提高西文方式下显示汉字的效率。文末给出了用Ｃ语言实现的动态维护及驻留ＶＲＡＭ程序。     

An automatic measurement device for the evaluation of the print quality of printed characters

When using OCR equipment (OCR = Optical Character Recognition) it is necessary to define shape and print quality of the characters in national and international standards.The paper gives a review of the standardization of the character fonts OCR A and OCR B for optical character recognition. All relevant parameters are discussed which define the print quality of printed characters. A critical review of two measurement methods used so far for the evaluation of print quality parameters is given. The improvement of the measurement methods led to the development of an automatic measurement device which is described in detail.The automatic measurement device consists of a high precision scanning device to digitize the printed characters and a computer program for the evaluation of the data. The mechanical construction and the properties of the scanning device are explained. The computer program consists of two main parts for preprocessing of the scanned data and for the evaluation of the different print parameters.Test results are reported and possible applications of the measurement device are discussed.     

Exploiting the least recently used page replacement algorithm

Many implementations of paged virtual memory systems employ demand fetching with least recently used (LRU) replacement. The stack characteristic of LRU replacement implies that a reference string which repeatedly accesses a number of pages in sequence will cause a page fault for each successive page referenced when the number of pages is greater than the number of page frames allocated to the program's LRU stack. In certain circumstances when the individual operations being performed on the referenced string are independent, or more precisely are commutative, the order of alternate page reference sequences can be reversed. This paper considers sequences which cannot be reversed and shows how placement of information on pages can achieve a similar effect if at least half the pages can be held in the LRU stack.     

关于印染工业污染防治的研究

印染工业是我国的传统产业之一,也是我国的污染大户．由于印染废水的成分复杂,末端处理负荷较重,再加之目前“绿色壁垒”、“绿色纺织品”的提出,给中国印染工业带来巨大挑战．面对如此挑战,防治印染工业污染,推行清洁生产是很必要的．从管理方面、技术方面、原材料等方面探讨了防治印染工业污染、推行清洁生产的途径与方法．     

Improving page prefetching with prior knowledge

Prefetching is a technique applied to memory management policies in which pages are brought into memory before they are actually needed. In this study, prior knowledge of program behavior obtained through trace data is used to parameterize a variation of the working set memory management policy supporting demand page prefetching using one page lookahead. Two new algorithms supporting double page prefetching are proposed. A comparative analysis of them is made.Evaluation of the techniques through trace driven simulation shows that, in general, they are very effective in reducing the page fault rate and in some cases the space time product. As expected, memory occupancy increases, but usually by small amounts. The results are encouraging for their ability to improve performance for a variety of programs which exhibit some form of locality (spatial and/or temporal).     

Minimization of demand paging for the LRU stack model of program behavior

The minimization of page faults in a demand paging environment where program behavior is described by the LRU stack model is studied. Previous work on this subject considered a specific type of stack probability distribution. As there exist practical situations which do not satisfy this assumption, we extend the analysis to arbitrary distributions. The minimization is stated as an optimization problem under constraints, a method to obtain a class of optimal solution is presented, and a fixed-space replacement algorithm to implement these solutions is proposed. The parameters of this replacement algorithm can be varied to adapt to specific stack probability distributions and to the number of allocated pages in memory. This paper also determines a necessary and sufficient condition for the optimality of the LRU algorithm.