基于B/S架构的电子学档系统设计与实现

介绍基于B/S架构的多用户电子学档系统的设计与开发,探讨系统实现的关键技术。该系统应用于教学技能的培训,辅助网络教学,把师范生的学习过程、教师的教学过程、学习的评价过程融合为一体,提供教师和师范生双向运用的价值。     

基于B/S模式的在线考试系统

针对目前传统考试方式的不足,介绍一个在Web环境下,利用ASP/ADO技术开发基于Brower/Server模式的在线考试系统的总体方案、主要功能模块及其相关实现技术.该系统实现了真正的无纸化在线考试,大大减轻了教师的工作量,也保证了考试的公正性和合理性.系统功能齐全、界面友好,具有推广使用价值.     

基于扩充的GIX/M/1/N排队系统的主动队列管理算法性能评价模型

为了评价主动队列管理(AQM Active Queue Management)算法的性能,通过在标准的排队系统GIX/M/1/N中嵌入主动队列管理(AQM)算法的方法,建立了一个扩充的GIX/M/1/N排队系统。利用该扩充的GIX/M/1/N排队系统和Internet业务流量自相似性的特征,提出了一种评价AQM算法在非响应业务流量下的性能的分析方法,并据此评价了TD,RED,GRED和Adaptive RED等4个经典的AQM算法。为了验证该分析方法的合理性,利用NS2进行了一系列的仿真实验。结果表明,该分析方法所得结果与仿真实验所得结果一致,因此该分析方法能用于评价AQM算法的性能。     

基于CS/BS模式的课程教学质量测评系统的设计与实现

教学管理信息化是高校教学管理发展的趋势,教学质量评价的信息化建设是教学管理信息化建设的一个重要环节。本文以"广州城建职业学院教学质量评价系统"为蓝本,从系统需求分析入手,介绍了CS/BS模式,系统实现的主要技术问题,设计并实现了基于CS/BS模式的课程教学质量测评系统。     

一种基于B/S结构与C/S结构结合的新体系结构

在对B/S结构和C/S结构进行充分分析比较的情况下,简述了今后发展的前景,并提出了一种新的体系结构。结合B/S与C/S,将组件技术COM+和ActiveX技术分别应用在服务器端和客户端,从而开发出高效、安全的应用系统。     

基于B/S结构与C/S结构的混合体系结构的研究

本文在介绍了B/S和C/S的基础上,通过对B/S结构和C/S结构进行充分分析比较后,简述了今后发展的前景,并提出了一种新的体系结构--结合B/S与C/S,将组件技术COM＋和AcdveX技术分别应用在服务器端和客户端,从而开发出高效、安全的应用系统。     

基于B/S结构的学生选课系统设计与实现

针对传统选课方式存在的不足，设计基于浏览器/服务器模式（Browser/Server,B/S）结构的学生选课系统。首先介绍了B/S和SQL Server数据库的基本原理，其次分析了学生用户需求、教师用户需求以及教务管理需求，最后探讨了系统中学生、教师及教育管理员的设计内容。测试结果表明，该系统的响应速度快，能够满足高校师生及教务管理的需求。     

基于指纹识别和C/M/S结构的保管箱管理系统

为了满足银行保管箱业务需求,充分利用银行网络资源,提高业务管理的信息化水平,在指纹识别基本原理的基础上,设计出一种基于指纹识别和C/M/S网络体系结构的银行保管箱管理系统.文中从实际需求和应用出发,归纳并设计了指纹特征信息库的管理方案,提出了利用银行现有网络架构该系统C/M/S体系结构的技术策略,描述了系统各层次的功能,并对具体的软件实现方法进行了简要的阐述.该系统集先进的生物识别技术和网络技术于一体,将指纹识别应用于银行保管箱业务中,具有较高的安全性和广泛的应用价值.     

I/O系统性能测评与分析

输入输出系统(I/O系统)作为计算机系统中的一个重要组成部分,其性能的好坏对CPU的性能有很大的影响,因此本文从I/O系统基本概述开始介绍,并采用了模型模拟和实际测量的方法来衡量I/O系统性能,并做了相关的评价分析.     

基于B/S架构的教师信息管理系统设计与实现

教师信息管理系统使用B/S架构,Microsoft Visual Studio软件系统的开发工具和Microsoft SQL Server数据库.教师信息管理系统的目标是实现教师信息管理自动化,提高学校信息管理,提升教师信息管理的可控性和安全性.教师信息管理系统的应用能够降低教师信息管理的成本,提高学校对教师管理的执行力.通过分析国内外相关研究的发展现状,提出以Microsoft ASP.NET技术为基础的开发的方案.     

M/G/c/K blocking probability models and system performance

An exact solution for the M/G/c/K model is only possible for special cases, such as exponential service, a single server, or no waiting room at all. Instead of basing the approximation on an infinite capacity queue as is often the case, an approximation based on a closed-form expression derivable from the finite capacity exponential queue is presented. Properties of the closed-form expression along with its use in approximating the blocking probability of M/G/c/K systems are discussed. Extensive experiments are provided to test and verify the efficacy of our approximate results.     

设计模式变体的描述与验证*

为解决标准设计模式演化后难以检测的问题,引入设计模式变体思想,以Bridge模式为例,给出了八种常用的变体实现,并以人工形式挖掘了四种开源系统中Bridge模式变体的基准数,接着在Apache Ant1.6.2与JHotDraw5.1开源系统中通过六种主流设计模式检测工具进行了变体检测实验。试验结果表明,FCA-CBR方法简单有效,对2种开源系统中Bridge模式变体检测的精确率达到60%与48.1%,与先前方法相比有了较大的提高。     

(r∞, n12, s12) measurements on the 2-CPU CRAY X-MP

We report performance measurements made on the 2-CPU CRAY X-MP at ECMWF, Reading. Vector (SIMD) performance on one CPU is interpreted by the two parameters ($\text{r}{}_{\mathrm{\infty }}\text{, n}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}$), and we find for dyadic operations using FORTRAN $\text{r}{}_{\mathrm{\infty }}\text{= 70}\text{Mflop/s}\text{, n}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{= 53}\text{flop}$. All vector triadic operations produce $\text{r}{}_{\mathrm{\infty }}\text{= 107}\text{Mflop/s}\text{, n}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{= 45}\text{flop}$; and a triadic operation with two vectors and one scalar gives r_∞ = 148 Mflop/s and $\text{n}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{= 60}\text{flop}$. MIMD performance using both CPUs on one job is interpreted with the two parameters ($\text{r}{}_{\mathrm{\infty }}\text{, s}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}$), where $\text{s}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}$ is the amount of arithmetic that could have been done during the time taken to synchronize the two CPUs. We find, for dyadic operations using the TSKSTART and TSKWAIT synchronization primitives, that r_∞ = 130 Mflop/s and $\text{s}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{= 5700}\text{flop}$. This means that a job must contain more than ～ 6000 floating-point operations if it is to run at more than 50% of the maximum performance when split between both CPUs by this method. Less expensive synchronization methods using LOCKS and EVENTS reduces $\text{s}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}$ to 4000 flop and 2000 flop respectively. A simplified form of LOCK synchronization written in CAL code further reduces $\text{s}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}$ to 220 flop. This is probably the minimum possible value for synchronization overhead on the CRAY X-MP.     

Complex random sample scheduling and its application to an N/M/F/Fmax problem

“Complex Random Sample Scheduling(CRSS)” was proposed in this paper as an efficient heuristic method for solving any permutation scheduling problems. To show the effectiveness of the proposed CRSS, it was applied to an N-job, M-machine, permutation flowshop scheduling problem to minimize makespan, N/M/F/F_max. Numerical experiments made it clear that the proposed CRSS provides a schedule very close to the near-optimal schedule obtained by the existing promising heuristic methods such as taboo search and simulated annealing, within less computation time than these heuristic methods.     

Geom/G/1/n system with LIFO discipline without interrupts and constrained total amount of customers

Consideration was given to the discrete-time queuing system with inversive servicing without interrupts, second-order geometrical arrivals, arbitrary (discrete) distribution of the customer length, and finite buffer. Each arriving customer has length and random volume. The total volume of the customers sojourning in the system is bounded by some value. Formulas of the stationary state probabilities and stationary distribution of the time of customer sojourn in the system were established.     

Efficient implementation of Johnson''s rule for the n/2/F/Fmax scheduling problem

Several efficient algorithms of O(n log n) computational complexity, for the Johnson's rule to schedule a set of simultaneously available jobs on two machines in a flowship to minimize the maximum job flowtime have appeared in the literature. A modified version of one of these algorithms is presented which not only simplifies the programming effort for implementation but is also able to generate all possible optimal sequences obtainable from Johnson's rule.     

On the M/Ck/1 queue

We obtain the exact analytic expression of the probability distribution of the number of units in a single server queue with Poisson arrivals and Coxian service time distribution (notated as M/C_k/1). A recursive procedure for calculating this probability distribution is given. The well-known queues M/E_k/1 and M/D/1 are re-derived as special cases of the M/C_k/1 queue. Finally, the cases of M/C₂/1 and M/C₃/1 are fully worked out.