计算机组成原理与汇编语言程序设计期末复习

1 计算机中的信息表示1.1 复习要点（1）掌握十进制和二进制、十进制和十六进制之间的互相转换,注意整数部分和小数部分需要分别转换。（2）已知X原,求X补或真值。已知X反,求真值。（3）掌握补码左移和右移的移位规则。（4）掌握带符号定点整数的原码绝对值最大正数、最大负数,补码绝对值最大负数,反码绝对值最大负数。（5）掌握浮点数格式,浮点数的规格化（条件）。（6）当给定某浮点数字长;阶码,阶符,补码表示,R=2;尾数,数符,补码表示;规格化的条件后,求其绝对值最大负数、绝对值最小负数、非零最小正数。     

原码、反码、补码的学习技巧

计算机专业的好多课程都要涉及到原码、反码、补码的知识，但是这个知识点却是个难点，很多同学学了很多遍，仍然是一知半解。作者根据这些年讲课过程中积累的一些经验和体会，根据学生在学习过程中经常遇到的困难，谈一谈自己的看法。     

浮点数存储精度丢失问题——由学生提问所引发的思考

浮点数在计算机中的存储形式一直是计算机程序设计课程的难点,其存储精度的丢失往往会影响到程序的准确性和可靠性。从一道关于浮点数运算的学生提问入手,总结浮点数教学过程中的一些难点问题,包括浮点数在计算机中存储的格式、误差、范围、精度等,从各个方面进行了系统深入的分析,力求给出一个清晰的描述。     

浮点数的教学实践与研究

数的表示与运算是一个牵扯到多门计算机课程的重点内容,而浮点数则是难点内容。本文就浮点数的一般表示及标准表示的方法、范围、存储格式、精度等从各个层面上进行了系统而深入地比较、分析和研究,力求给读者一个清晰的概述。     

计算机组成原理综合练习

Ⅰ　练习题1　填空题(把正确的答案(小数点后保留8位)填在括号内)( 1) ( 0 .0 1110 0 0 1) BCD=(　　　　) 10 =(　　　　) 2 =(　　　　) 16( 2 )X =- 0 .110 1　　　　　[X]原=(　　　　)[X]补=(　　　　)　[-X]补=(　　　　)[-Y]补=( 11111)　[Y]原=(　　　　)[Y]补=(　　　　)　Y =(　　　　)[Y -X]补=(　　　　)( 3)按照IEEE标准,一个浮点数由1位、n位和m位组成,其中的部分选用移码表示,选用原码表示。该浮点数的数值范围主要取决于的位数,而数据的表示精度主要取决于的位数。浮点数的零是均为零,非零值的规格化的浮点数尾数数…     

两类广义循环矩阵与向量的乘积

给出计算拟斜循环矩阵与向量乘积的算法,该算法需要3/2n^2＋O（n）个浮点数运算,而相比之下,常规的矩阵与向量的乘积运算则需要2n^2＋O（n）个浮点数运算,对于Hermitian循环矩阵,能得到类似的结果。     

C语言浮点数探析

浮点数运算存在精度、比较以及舍入误差等方面的问题,而这些问题直接影响到学生对浮点数的理解和教学案例的准确性。针对这一情况,以C语言浮点数机制为研究基础,对浮点数的存储格式、有效位数、取值范围的含义、精度与应用等方面问题进行实证研究,获得了一些有用的结果。     

快速浮点运算在FPGA中的实现

浮点计算是计算机计算中的一种重要计算方式,计算过程比较复杂,一般的软件在计算时有一定的速度缺陷。在IEEE754标准下通过FPGA器件对单精度浮点数的四则运算进行运算模块设计,利用FPGA的流水线工作特点,提高浮点计算速度,缩短产品开发周期,在浮点运算的规则下实现了FPGA器件上的单精度浮点数运算。     

浮点数不能判等研究

在软件开发过程中,浮点数的表示和运算一直是重点也是难点。基于目前计算机界广泛使用的IEEE754浮点标准,针对C/C++语言中“浮点数为什么不能判等”这个典型问题进行了分析和研究,力求给软件开发及测试人员一个清晰的阐述,研究中得出了两个有趣的结论。     

微机原理及应用举要

第一章 计算机中的数制和码制 1.掌握各种进位计数制的表示方法及相互间的转换方法。 2.掌握机器数、真值,无符号数,有符号数,原码、反码、补码及[—x]_补的概念及其转换方法。 3.掌握BCD码与各进位计数制间的转换方法。 4.掌握补码加减法及进位、溢出的判断。 5.掌握与、或、异或等逻辑运算的方法。 第二章 微机概述 1.初步建立起微机的整体概念。 2.掌握微机的组成部分及各部分间的相互关系,掌握总线的概念及其组成,掌握各寄存器的功能。     

机器数在数轴上的表示方法

介绍了机器数在数轴上的几何表示方法，并用此方法分析了补码运算的溢出问题．     

Bridging the gap: Fraction understanding is central to mathematics achievement in students from three different continents

Numerical understanding and arithmetic skills are easier to acquire for whole numbers than fractions. The integrated theory of numerical development posits that, in addition to these differences, whole numbers and fractions also have important commonalities. In both, students need to learn how to interpret number symbols in terms of the magnitudes to which they refer, and this magnitude understanding is central to general mathematical competence. We investigated relations among fraction magnitude understanding, arithmetic and general mathematical abilities in countries differing in educational practices: U.S., China and Belgium. Despite country-specific differences in absolute level of fraction knowledge, 6th and 8th graders' fraction magnitude understanding was positively related to their general mathematical achievement in all countries, and this relation remained significant after controlling for fraction arithmetic knowledge in almost all combinations of country and age group. These findings suggest that instructional interventions should target learners' interpretation of fractions as magnitudes, e.g., by practicing translating fractions into positions on number lines.     

"数的定点表示与浮点表示"问题分析

为“数的定点表示与浮点表示”的探究式教学设计了一系列问题，并用直观的方式分析了这些问题。这对于深入理解定点带符号数的数据特征、规格化浮点数的表示范围、定点表示与浮点表示的比较有一定的指导意义。     

How Are Symbols and Nonsymbolic Numerical Magnitudes Related? Exploring Bidirectional Relationships in Early Numeracy

What is the nature of the relationship between different lower‐level numerical skills and their role in developing arithmetic skills? We consider the hypothesis of a reciprocal relationship between the development of symbolic (e.g., Arabic numerals) and nonsymbolic (e.g., arrays of objects) numerical magnitude processing. Evidence for bidirectional relationships between symbolic and nonsymbolic numerical magnitude skill development is examined. Overall, present evidence is more indicative of an influence of symbolic numerical magnitude skills on the development of nonsymbolic numerical magnitude skills than vice versa. Looking forward, methodological issues pertinent to measuring the direction of such relationships are discussed. Also discussed is the important role that training studies need to play to further understand the complex relationships between basic number skills, and in turn their relationship with arithmetic. It is important that assumptions about relationships between lower and higher‐level cognitive skills are tested empirically and that seemingly counterintuitive relationships are given serious consideration.     

有符号数的补码速算方法研究

在计算补码的传统方法基础上,提出了一种快速准确的速算方法,并对其原理进行分析,给出了相应的例子说明,最后给出了该速算方法实现补码直接转换成原码的应用。     

Numerical magnitude representations influence arithmetic learning

This study examined whether the quality of first graders' (mean age = 7.2 years) numerical magnitude representations is correlated with, predictive of, and causally related to their arithmetic learning. The children's pretest numerical magnitude representations were found to be correlated with their pretest arithmetic knowledge and to be predictive of their learning of answers to unfamiliar arithmetic problems. The relation to learning of unfamiliar problems remained after controlling for prior arithmetic knowledge, short-term memory for numbers, and math achievement test scores. Moreover, presenting randomly chosen children with accurate visual representations of the magnitudes of addends and sums improved their learning of the answers to the problems. Thus, representations of numerical magnitude are both correlationally and causally related to arithmetic learning.     

An investigation of young children's academic arithmetic contexts

Research findings concerning students' interpretations of the equals sign appear to conflict with three recently developed models of early number development. It was hypothesized that the two groups of researchers investigated students' arithmetical understandings in situations that are, for most children, different contexts. Analysis of video-taped interviews conducted with 34 ending first grade children, drawn from five classrooms, supported this hypothesis. Interviews were conducted with the five classroom teachers and it was possible to relate the students' interpretations of the equals sign to social interaction patterns that typified classroom life during arithmetic instruction.     

北方方言中表可能的“了”的历时演变

在普通话里,可能补语的肯定式用[V得C]的形式来表现,可能补语的标志“得”放在[VC]之间。而北方方言里可能补语肯定式大部分用{VC了}的形式,可能补语的标志是“了”,放在[VC]之后。从历时演变的角度,探讨北方方言里可能补语的标记“了”的语法化过程以及与之相关的{VC了}的歧义问题,能够对北方方言中的可能补语有一个更深的认识。     

Principle of MSD floating-point division based on Newton-Raphson method on ternary optical computer

The division operation is not frequent relatively in traditional applications, but it is increasingly indispensable and important in many modern applications. In this paper, the implementation of modified signed-digit (MSD) floating-point division using Newton-Raphson method on the system of ternary optical computer (TOC) is studied. Since the addition of MSD floating-point is carry-free and the digit width of the system of TOC is large, it is easy to deal with the enough wide data and transform the division operation into multiplication and addition operations. And using data scan and truncation the problem of digits expansion is effectively solved in the range of error limit. The division gets the good results and the efficiency is high. The instance of MSD floating-point division shows that the method is feasible.     

Empirical testing of a cognitive model to account for neuropsychological functioning underlying arithmetic problem solving

The efficacy of a cognitive-based arithmetic problem-solving model (Dinnel, Glover, & Halpain, in press; Dinnel, Glover, & Ronning, 1984) was tested using 989 students with learning disabilities. Comprehensive neuropsychological test battery information was used to predict composite arithmetic test performance as a means of examining the utility of this model. Results of this study offer support for Dinnel et al.'s (Dinnel, Glover, & Halpain, in press; Dinnel, Glover, & Ronning, 1984) model in accounting for arithmetic performance under continuous visual stimulus conditions. However, these data indicate a more complex neuropsychological underpinning to arithmetic performance in both visual and aural stimulus conditions. The neuropsychological aspects of arithmetic problem solving were discussed in relationship to this cognitive-based model.