健康领域异构数据模式集成研究与实现

健康领域的数据由于来源不同,通常会使用不同元素或结构表示相同概念与关系,呈现出很强的异构性。为了满足异构数据统一查询工作的要求,需要研究与解决异构数据之间的语义冲突及结构冲突。在传统XML Schema模式集成算法基础上,计算语义相似度与结构相似度,同时对生成的候选匹配进行结构冲突检测,并解决结构冲突,最终生成具有较小冗余的全局模式,为异构数据的统一查询提供统一的全局视图。与传统模式集成算法相比,该方法很好地解决了模式集成中的关系嵌套冲突、关系方向冲突及实体属性冲突,减轻了模式集成后的冗余,具有更好的模式集成质量。     

物价变动会计模式及其对我国的启示

物价变动影响会计信息的可靠性和相关性.为此,在对当前国际上三种主流物价变动会计模式进行简单比较的基础上,介绍了我国减轻物价变动对会计信息影响的传统方法.但由于传统方法未能触及物价变动会计模式的改变,故不能系统地反映和消除物价变动对会计的影响.在分析了当前物价变动会计环境的基础上,思考了物价变动下当前会计模式的选择.     

基于包性质的局域网冗余数据消除技术分析

局域网已经在当前企事业单位信息化建设中扮演了一个重要的角色.但是在其通信过程中有大量的冗余数据存在,占用了带宽,降低了效率.论文通过分析数据包的性质,针对局域网提出了一种基于包性质的冗余数据消除技术.它将独立与共享缓存机制相结合,利用冗余阈值对低容量数据包进行过虑处理.     

关系数据库模式分解方法分析

一个关系数据库设计完成后,经常出现数据冗余和更新异常问题,这时,就要对关系模式进行分解。本文对关系模式分解的方法进行探讨,对于从事数据库设计人员,有一个很好的引导作用。     

《数据库原理》模拟试题解答及分析

下面给出模拟试题的分析与解答。(一)单项选择题1分析:在DBS中.数据冗余最好是完全消除.但要达到该目的.必须尽量把数据库中的关系模式分解成足够高的范式.但这样在查询时就要更多地使用费时的联接操作。所以考虑到操作效率,即尽可能少地使用联接操作.一般DBS中,     

基于决策树的防火墙访问控制策略检测与优化

访问控制策略是保证网络安全的核心技术之一。本文从防火墙管理中过滤规则的现状出发,分析了策略集中冗余和冲突产生的原因,讨论了基于决策树的方法对冗余和冲突进行检测、优化和消除,对所使用的方法进行了比较分析,为客观、合理、高效的管理访问控制策略,提高网络的安全性和可靠性做了基础性工作。     

基于分布式思维的云计算数据挖掘平台设计

在云计算背景下,海量数据信息相互影响,对原本的关联规则形成冗余干扰,导致当前以线性思维为主导的挖掘平台受到冗余干扰的影响,挖掘效率低下。为此,在分析传统方法弊端的基础上,提出了基于分布式思维的数据挖掘平台设计方法。为了解决冗余干扰问题,设计了一种冗余消除算法,以计算区域之间的相似度,形成分布式挖掘关联。试验结果证明,这种分布式数据挖掘平台可达到数据搜索简单、快速,且降低成本的目的。     

循环经济的机理分析

继传统经济发展模式(TEM)之后，人们越来越多地认识到循环经济发展模式(REM)的优越性。这项研究的目的是要表明如何推行循环经济。在对两种经济发展模式进行比较后，分析了循环经济的特点，重点分析了循环经济的内在机理。研究结果表明，推广循环经济发展模式的关键是消除自然资源和废物资源化的价格差。提出了消除这种价格差的可能的措施和途径。     

论通货膨胀环境中会计计量模式的选择

通货膨胀对传统会计模式提出了挑战,本文从国际上为消除通货膨胀影响所采取的会计计量模式出发,浅析了我国应选择的通货膨胀会计计量模式。     

数据库的规范化

设计一个好的数据库就要使我们的库中关系规范化，规范化的基本目的就是消除关系上的操作异常现象，规范化的基本方法就是模式分解．     

THE ROLE OF THE PRIMARY AND SECONDARY SCHOOL TEACHER

The teaching of reading is complicated by the fact that no one commercially produced set of ‘readers’ is adequate in all respects for the development of reading skills. The article which follows provides guidelines by which a complete reading scheme can be developed from a combination of reading schemes; including consideration of such fundamentals as compatibility of vocabulary, degree of repetition, phonic criteria and the selection of supplementary reading material.

This article has been prepared as a result of the author's conviction that no single available reading scheme alone provides sufficient material in the depth or variety necessary to effect the acquisition of reading skills by the normal child. The objective of the study described below was to establish a reading system which would, as nearly as possible, provide a continuous progression of reading material suitable for the wide range of ability of children passing through an infant school. For obvious reasons, the reading material needs to be selected from that which is commercially available and marketed as purportedly complete reading schemes.     

STAFF ASSESSMENT: THE DEVELOPMENT OF PROCEDURES FOR AUSTRALIAN UNIVERSITIES

In Australia, a recent Review of Efficiency and Effectiveness in Tertiary Education (Hudson, 1986) has produced an interest in formal staff appraisal schemes designed to assess performance of academic staff members for feedback and decision‐making purposes.

This paper outlines five principles which seem, after review of the literature on staff assessment schemes in the USA, to be important for the development of valid and reliable staff evaluation schemes. While the suggestions for Australian universities which have been made by the recent report are compatible with some of these principles, other principles are clearly violated, even in the sketchy outline of the scheme which has appeared to date.

It is suggested that these principles need to be emphasised once again in the hope that the Australian universities are able to gain from experiences which exist in the literature to date.     

共轭梯度法研究超晶格GaAs/AlxGa1－xAs的电子结构

改进了一种从头计算方法—共轭梯度方法 ,研究了超晶格 Ga As/ A lx Ga1 - x A s的电子结构 .根据超晶格的基本方程 ,在固定电子密度 n(z)下 ,求解了基本方程的本征值和本征函数 ,并由它们组成新的 n(z) ,重复此过程直到得自洽解 .另按超晶格基本方程的具体情况 ,对每个 kz独立地应用了共轭梯度方法 ,此可大大节省与 Gram-Schm it正交化有关的时间 .计算了超晶格的两个最低子能带之间的能量差和 F ermi能量 ,其模拟计算的结果与对应的实验数值一致     

由多模数三元三次方程组实现具有冗余信息的Hill密码体系

研究多模数三元三次同余方程组数值解法,且运用于经典Hill密码体系中,得到一种带有冗余信息的Hill密码体系.该加密方法因有信息冗余,使得解密信息具有一定的欺骗性.数值算例验证了这种新的Hill密码体系的正确性,且比传统、经典的Hill密码体系更具安全性.     

一种改进的带冗余项的LCD多行选址算法及其实现

提出了一种带有冗余项的多行选址驱动算法及电路实现方案,其适用于液晶显示驱动芯片。算法通过在行调制矩阵中增加冗余行,在显示数据矩阵中增加冗余数据,从而减少了列驱动电平数。此外,还提出了本算法的实现电路。实验结果表明,在液晶显示驱动芯片中,该算法能降低30%的驱动功耗。     

无双线性对的无证书（广义）签密方案安全性分析

为避免双线性对运算较耗时的缺陷,提高（广义）签密方案效率,学界提出了无双线性对运算的无证书签密方案和无双线性对运算的无证书广义签密方案。在随机预言机模型下证明该方案满足机密性和不可伪造性。通过具体的攻击方法证明了前一个方案存在伪造性攻击而后一个方案存在机密性攻击,分析了原方案不安全的原因。通过将公钥进行hash运算对前一个方案进行了改进,通过把签名部分分成两部分对后一个方案也进行了改进。对改进方案效率进行分析,结果表明改进方案安全高效。     

An Approach for Categorizing DIF in Polytomous Items

A widely used approach for categorizing the level of differential item functioning (DIF) in dichotomous items is the scheme proposed by Educational Testing Service (ETS) based on a transformation of the Mantel-Haeszel common odds ratio. In this article two classification schemes for DIF in polytomous items (referred to as the P1 and P2 schemes) are proposed that parallel the criteria set forth in the ETS scheme for dichotomous items. The theoretical equivalence of the P1 and P2 schemes to the ETS scheme is described, and the results of a simulation study conducted to examine the empirical equivalence of the P1 and P2 schemes to the ETS scheme are presented.     

Survey of Distinguished Teacher Award Schemes in Higher Education

Abstract

This article presents the results of an investigation into teacher award schemes undertaken for University College London in December 1997, prior to the introduction of such a scheme by the College. It was not intended to be an exhaustive survey, but designed rather to explore the issues, benefits and problems associated with the various types of award scheme. Information was obtained on a wide range of activities, both in the UK and overseas, and four types of award scheme were identified: traditional award schemes (i.e. prizes); teaching fellowship schemes; educational development grant schemes; and promotion/bonus schemes. The article describes the advantages and limitations of each model, including a summary of their purposes, processes and assessment criteria, presented as a guide to others who may be contemplating a scheme for their own institution.     

PERFORMANCE IMPROVEMENTS OF HDSL TRANSM ISSION SYSTEM BY USING M－DETECTOR WITH NOISE PREDICTION TECHNIQUE

ＰＥＲＦＯＲＭＡＮＣＥＩＭＰＲＯＶＥＭＥＮＴＳＯＦＨＤＳＬＴＲＡＮＳＭＩＳＳＩＯＮＳＹＳＴＥＭＢＹＵＳＩＮＧＭ－ＤＥＴＥＣＴＯＲＷＩＴＨＮＯＩＳＥＰＲＥＤＩＣＴＩＯＮＴＥＣＨＮＩＱＵＥＺｈａｏＣｈｕｎｍｉｎｇ（赵春明）ＣｈｅｎｇＳｈｉｘｉｎ（程时昕）...     

可编程控制器系统电源冗余

在现代工业及生活中,关键设备及连续生产要求要有足够的冗余电源。本文以火电厂输煤程控系统的可编程控制器供电为例,讨论可行的冗余方案。实际运行结果表明改造后的电源冗余措施实现了控制系统对电源的要求,效果良好。