计算机科学概论论文--陈旭光

计算机科学概论--陈旭光 计算机技术概论 计算机科学是研究计算机及其周围各种现象和规律的科学，亦即研究计算机系统结构、程序系统(即软件)、人工智能以及计算本身的性质和问的学科。 计算机科学是一门包含各种各样与计算和信息处理相关主题的系统学科，从抽象的算法分析、形式化语法等等，到更具体的主题如编程语言、程序设计、软件和硬件等。作为一门学科，它与数学、计算机程序设计、软件工程和计算机工程有显著的不同，却通常被混淆，尽管这些学科之间存在不同程度的交叉和覆盖。 计算机科学的分支学科: 1计算机科学。计算机科学包括计算的理论、算法和实现，以及机器人技术、计算机视觉、智能系统、生物信息学和其他新兴的有前途的领域。计算机科学是计算各学科的基础。2计算机工程。计算机工程是对现代计算系统和由计算机控制的有关设备上的软件与硬件的设计、构造、实施和维护进行研究的学科。3软件工程。软件工程是指以系统、学科、定量的方法，把工程应用于软件的开发、运行和维护;同时，展开对上述过程中各种方法和途径进行研究的学科。4信息系统。信息系统是指如何将信息技术的方法与企业生产和商业流通结合起来，以满足这些行业需求的学科。5信息技术。信息技术从广义上来说，它包括了所有计算技术的各个方面，在此专指作为一门学科的信息技术。它侧重在一定组织及社会环境下，通过选择、创造、应用、集成和管理的计算技术来满足用户的需求。 enforced thermal insulation starts checking system, issued by the thermal insulation construction before you start to notice, transfer inspection of upper and lower operation and transfer of records. For outdoor operation, pipeline equipment to effectively carry out the insulation waterproof measures fail to install protective panels in part with three tarpaulin cover, to prevent insulation from moisture. Insulation seam Michael Jackson 5mm, joints, joints >100mm, insulation thickness tolerance (+10MM~ – 5mm), appropriate material elastic banding, spacing according to the design requirements, rigid insulation soft materials for construction joints tight; And large-diameter vertical pipe for high temperature pipeline in strict accordance with design drawings called for the establishment of expansion joints and holding bracket; Design requirements into a removable type of insulation, in strict accordance with specifications disconnect from the other insulation; Surface insulation boards in the technology of plastering construction of woven cloth to prevent pollution and protective panels flush with the surface interface, tight and clean. Site measurement of insulation boards for elbow shape cutting, ensure that each piece of lapped traffic, arc transition of natural, beautiful, screws up. Stampede outside construction personnel is strictly prohibited and shelve objects directly on the outer shield. In order to prevent the pollution-prone heater, channel area of secondary pollution of large-diameter pipes and other equipment, weaving cloth, and erection of the separation platform for preservation. Thermal insulation construction, on-hook tack welded to the consolidated line, to ensure evenly spaced, and the hook nailed down ... See next page flow chart management process. 7.2 General requirements for protective product protection 计算机科学涉及的主要领域: 计算机科学的的几个分支领域包括:数值和符号计算、算法和数据结构、体系结构、操作系统、程序设计语言、软件方法学和工程、数据库和信息检索、计算理论、人工智能和机器人学等。 1.数值和符号计算 数值和符号计算研究的是有效和精确地求解由数学模型所导出方程的一般方法。基本问题包括:怎样才能按照给定精度很快地接触给定类型的方程;怎样对方程进行符号运算，例如积分、微分和化简为最小项等;怎样把这些问题的回答加入到有效的可靠的、高质量的数学软件包中去。 2.体系结构 体系结构主要用于研究的是将硬件和软件组织成有效和可靠系统的方法。基本问题包括:什么是在一个机器中实现数据处理、存储和通信的最好办法,如何设计和控制大型计算系统并且使它们能过在有错误和故障的情况下完成预期的工作,什么类型的体系结构能过使许多处理器单元有效地协同工作，实现并行计算,怎样测试度量计算机的性能, 3.操作系统 操作系统研究的是允许多种资源在程序执行中有效配合的控制机制。基本问题包括:在计算 机系统运行的各级上可见的对象和允许的操作是什么;每一类资源允许有效使用的最小操作集是什么;怎样组织接口，使得用户只处理资enforced thermal insulation starts checking system, issued by the thermal insulation construction before you start to notice, transfer inspection of upper and lower operation and transfer of records. For outdoor operation, pipeline equipment to effectively carry out the insulation waterproof measures fail to install protective panels in part with three tarpaulin cover, to prevent insulation from moisture. Insulation seam Michael Jackson 5mm, joints, joints >100mm, insulation thickness tolerance (+10MM~ – 5mm), appropriate material elastic banding, spacing according to the design requirements, rigid insulation soft materials for construction joints tight; And large-diameter vertical pipe for high temperature pipeline in strict accordance with design drawings called for the establishment of expansion joints and holding bracket; Design requirements into a removable type of insulation, in strict accordance with specifications disconnect from the other insulation; Surface insulation boards in the technology of plastering construction of woven cloth to prevent pollution and protective panels flush with the surface interface, tight and clean. Site measurement of insulation boards for elbow shape cutting, ensure that each piece of lapped traffic, arc transition of natural, beautiful, screws up. Stampede outside construction personnel is strictly prohibited and shelve objects directly on the outer shield. In order to prevent the pollution-prone heater, channel area of secondary pollution of large-diameter pipes and other equipment, weaving cloth, and erection of the separation platform for preservation. Thermal insulation construction, on-hook tack welded to the consolidated line, to ensure evenly spaced, and the hook nailed down ... See next page flow chart management process. 7.2 General requirements for protective product protection 源的抽象形式，而可以不管硬件的实际细节;对作业调度、存储器管理、通信、软件资源存取、并发任务间的通信、可靠性和安全的有效控制策略是什么;系统应该在什么功能上扩展;怎样组织分布式计算，使得许多由通信网络连接起来的独立的计算机能够参与同一计算。 4.数据结构和算法 数据结构和算法主要研究的是一些特定类型的问题及相对应的数据结构和解决方法。基本问题包括:对给定类型的问题，最好的算法是什么;它们要求多少存储空间和时间;空间与时间的折衷是什么;存取数据最好的方法是什么;最好算法的最坏情况是什么;算法的运行(按平均来说)好到何种程度;算法一般化到何种程度，即什么类型的问题可以用类似的方法处理。 5.程序设计 程序设计研究的是执行算法的虚拟机的符号达、算法和数据的符号表达以及从高级语言到机器码的有效的翻译。基本问题包括:由一种语言给出的虚拟机的可能的组织(数据类型、运算、控制结构、引入新类型相运算的机制)是什么;这些抽象怎样在计算机上实现;用什么样的符号表达(语法)可以有效地指明计算机应该做什么。 6.软件工程 软件工程研究的是满足技术要求，安全、可靠、可信的程序和大型软件系统的设计。基本问题包括:在程序和程序设计系统的开发背后的原理是什么;怎样去证明程序或系统满足它的技术要求;怎样给定技术要求，使之不遗漏重要的情况，而且可以分析它的安全性;怎enforced thermal insulation starts checking system, issued by the thermal insulation construction before you start to notice, transfer inspection of upper and lower operation and transfer of records. For outdoor operation, pipeline equipment to effectively carry out the insulation waterproof measures fail to install protective panels in part with three tarpaulin cover, to prevent insulation from moisture. Insulation seam Michael Jackson 5mm, joints, joints >100mm, insulation thickness tolerance (+10MM~ – 5mm), appropriate material elastic banding, spacing according to the design requirements, rigid insulation soft materials for construction joints tight; And large-diameter vertical pipe for high temperature pipeline in strict accordance with design drawings called for the establishment of expansion joints and holding bracket; Design requirements into a removable type of insulation, in strict accordance with specifications disconnect from the other insulation; Surface insulation boards in the technology of plastering construction of woven cloth to prevent pollution and protective panels flush with the surface interface, tight and clean. Site measurement of insulation boards for elbow shape cutting, ensure that each piece of lapped traffic, arc transition of natural, beautiful, screws up. Stampede outside construction personnel is strictly prohibited and shelve objects directly on the outer shield. In order to prevent the pollution-prone heater, channel area of secondary pollution of large-diameter pipes and other equipment, weaving cloth, and erection of the separation platform for preservation. Thermal insulation construction, on-hook tack welded to the consolidated line, to ensure evenly spaced, and the hook nailed down ... See next page flow chart management process. 7.2 General requirements for protective product protection 样使软件系统通过不同阶段不断改进;怎样将软件设计得易理解和易修改。 7(数据库和信息检索 数据库和信息检索研究的是对大量持续的分享的数据集合的组织，使之能够进行有效的查询和刷新。基本问题包括:用什么样的模型化概念去表示数据元和它们之间的关系;怎样把存储、定位、匹配、检索等基本操作组合成有效的事务处理;这些事务处理怎么与用户有效地交互作用;怎样把高级查询翻译成高性能的程序;什么样的系统结构能有效地检索和刷新;怎样保护数据，以抵制非法存取，泄露或破坏;怎样保护大型数据库不会由于同时刷新而导致不相容;当数据分散在许多台计算机时，怎样使安全保护和访问性能二者得以兼顾;怎样索引和分类正文，以达到有效的检索。 8(人工智能和计算理论 人工智能和计算理论研究的是动物和人类(智能)行为模型。基本的问题包括:摹本的行为模型是什么，我们怎样建造机器来棋拟;由规则赋值、推理、演绎和模式计算所描写的智能可以达到什么程度;由这些模型模拟行为的机器最终能达到什么性能;感知的数据应如何编码，使得类似的模式有类似的码字;驱动码怎样和感知码相联系;学习系统的体系结构如何，以及这些系统如何表示它们对外部世界的知识;怎样才能用有穷的离散过程去精确地逼近连续或无穷的过程;怎么处理逼近导致的误差等。 计算机与计算机模型 enforced thermal insulation starts checking system, issued by the thermal insulation construction before you start to notice, transfer inspection of upper and lower operation and transfer of records. For outdoor operation, pipeline equipment to effectively carry out the insulation waterproof measures fail to install protective panels in part with three tarpaulin cover, to prevent insulation from moisture. Insulation seam Michael Jackson 5mm, joints, joints >100mm, insulation thickness tolerance (+10MM~ – 5mm), appropriate material elastic banding, spacing according to the design requirements, rigid insulation soft materials for construction joints tight; And large-diameter vertical pipe for high temperature pipeline in strict accordance with design drawings called for the establishment of expansion joints and holding bracket; Design requirements into a removable type of insulation, in strict accordance with specifications disconnect from the other insulation; Surface insulation boards in the technology of plastering construction of woven cloth to prevent pollution and protective panels flush with the surface interface, tight and clean. Site measurement of insulation boards for elbow shape cutting, ensure that each piece of lapped traffic, arc transition of natural, beautiful, screws up. Stampede outside construction personnel is strictly prohibited and shelve objects directly on the outer shield. In order to prevent the pollution-prone heater, channel area of secondary pollution of large-diameter pipes and other equipment, weaving cloth, and erection of the separation platform for preservation. Thermal insulation construction, on-hook tack welded to the consolidated line, to ensure evenly spaced, and the hook nailed down ... See next page flow chart management process. 7.2 General requirements for protective product protection 1936年5月28日，图灵向伦敦权威的数学杂志投了一篇论文，题为“论可计算数及其在判定问题上的应用”。在这篇开创性的论文中，图灵给“可计算性”下了一个严格的数学定义，并提出著名的“图灵机(Turing Machine)”的设想:“它可以表达成一台单一的特殊机器，这种形式的机器可以被塑造成去做到所有工作。事实上，它可以被塑造成如同任何其他机器的模型般工作。这种特殊机器或许可以被称呼为通用机器。” 这样，他就把人的思维机械化。这种理想中的机器被称为“图灵机”。 图灵机是一种抽象计算模型，用来精确定义可计算函数。 冯?诺依曼理论的思想是:应该把程序和数据一起存储在存储器里，让计算机自己负责从存储器里提取指令，执行指令，循环式地执行这两个动作。这样，计算机在执行程序的过程中，就可以完全摆脱外界的影响，以自己可能的速度自动地运行。按照这种原理构造出来的计算机就是“存储程序控制计算机”，也被称做“冯?诺依曼计算机”。 计算机的发展 算盘时代: 这一阶段出现了表示语言和数字的文字及其书写工具，最主要的计算工具是算盘。 机械时代: 这一时期计算装置的特点是借助于各种机械装置齿轮杠杆等自动传送(十进位)，而机械装置的动力则来自计算人员的手。 机电时代: enforced thermal insulation starts checking system, issued by the thermal insulation construction before you start to notice, transfer inspection of upper and lower operation and transfer of records. For outdoor operation, pipeline equipment to effectively carry out the insulation waterproof measures fail to install protective panels in part with three tarpaulin cover, to prevent insulation from moisture. Insulation seam Michael Jackson 5mm, joints, joints >100mm, insulation thickness tolerance (+10MM~ – 5mm), appropriate material elastic banding, spacing according to the design requirements, rigid insulation soft materials for construction joints tight; And large-diameter vertical pipe for high temperature pipeline in strict accordance with design drawings called for the establishment of expansion joints and holding bracket; Design requirements into a removable type of insulation, in strict accordance with specifications disconnect from the other insulation; Surface insulation boards in the technology of plastering construction of woven cloth to prevent pollution and protective panels flush with the surface interface, tight and clean. Site measurement of insulation boards for elbow shape cutting, ensure that each piece of lapped traffic, arc transition of natural, beautiful, screws up. Stampede outside construction personnel is strictly prohibited and shelve objects directly on the outer shield. In order to prevent the pollution-prone heater, channel area of secondary pollution of large-diameter pipes and other equipment, weaving cloth, and erection of the separation platform for preservation. Thermal insulation construction, on-hook tack welded to the consolidated line, to ensure evenly spaced, and the hook nailed down ... See next page flow chart management process. 7.2 General requirements for protective product protection 使用电力作为计算机器动力，但计算机构本身还是机械式的。 第一代计算机 1946年-1957年: 1946年世界上第一台电子计算机 ENIAC(Electronic Numerical Integrator And Computer，读作“埃尼阿克”)在美国宾夕法尼亚大学研制成功。 第一代电子计算机主要特点:利用真空管制造电子元件，利用穿孔卡作为主要的存储介质，体积庞大，重量惊人，耗电量大。 第二代计算机 1958年~1964年: 使用用晶体管的计算机被称作第二代计算机。和真空管计算机相比，晶体管计算机无论是耗电量还是产生的热能都大大降低，而可靠性和计算能力则大为提高。主存储器均采用磁心存储器，磁鼓和磁盘开始用作主要的辅助存储器。 1953年 ~1963年期间，IBM 相继推出IBM 701、IBM 650、等经典机型，成为市场领导者。并于1964年研制成功IBM 360，开启了第三代计算机的设计时代。 第三代计算机 1965年~1975年: 使用集成电路代替晶体管，使用硅半导体制造存储器。广泛使用微程序技术，简化处理机设计。系列化通用化和标准化是这一时期计算机设计的基本思想。 第四代计算机 1972年~至今: 大规模、超大规模集成电路迅速代替中小规模集成电路。 产生了微处理器和微型计算机 。产生了字长4位、8位、16位、32位和64enforced thermal insulation starts checking system, issued by the thermal insulation construction before you start to notice, transfer inspection of upper and lower operation and transfer of records. For outdoor operation, pipeline equipment to effectively carry out the insulation waterproof measures fail to install protective panels in part with three tarpaulin cover, to prevent insulation from moisture. Insulation seam Michael Jackson 5mm, joints, joints >100mm, insulation thickness tolerance (+10MM~ – 5mm), appropriate material elastic banding, spacing according to the design requirements, rigid insulation soft materials for construction joints tight; And large-diameter vertical pipe for high temperature pipeline in strict accordance with design drawings called for the establishment of expansion joints and holding bracket; Design requirements into a removable type of insulation, in strict accordance with specifications disconnect from the other insulation; Surface insulation boards in the technology of plastering construction of woven cloth to prevent pollution and protective panels flush with the surface interface, tight and clean. Site measurement of insulation boards for elbow shape cutting, ensure that each piece of lapped traffic, arc transition of natural, beautiful, screws up. Stampede outside construction personnel is strictly prohibited and shelve objects directly on the outer shield. In order to prevent the pollution-prone heater, channel area of secondary pollution of large-diameter pipes and other equipment, weaving cloth, and erection of the separation platform for preservation. Thermal insulation construction, on-hook tack welded to the consolidated line, to ensure evenly spaced, and the hook nailed down ... See next page flow chart management process. 7.2 General requirements for protective product protection 位的微型计算机，计算机的性能迅速提高。 未来新一代的计算机: 生物计算机: 采用生物工程技术产生的蛋白质分子制成生物芯片，其运算过程是蛋白质分子与周围物理化学介质的相互作用过程。 量子计算机: 采用一种链状分子聚合物的特性来表示开与关的状态，利用激光脉冲来改变分子的状态，使信息沿着聚合物移动，从而进行运算。 光子计算机: 采用光学技术，由光器件构成的计算机。在光器件方面研制的基本部件有:用于进行图像处理的快速傅立叶变换部件，用于进行信息处理的光乘法、加法运算器。 超导计算机: 采用超导元器件和电路组成的计算机。其基本逻辑单元是约瑟夫逊开关器件，它的速度比现有半导体开关快10-100倍，功耗仅为后者的0.01-0.001。 在学了计算科学概论之后，让我更深入的了解了我将来要从事的学科。计算科学概论指导着我们该怎么学习计算机。让我更清楚的知道我们信息安全专业的方向。正如计算科学这座大楼一样，在不断的成长。信息安全也必将随着网络的进一步发展而更多的被人们重视。总之学习了这门课之后让我受益匪浅，也知道自己应该好好努力，争enforced thermal insulation starts checking system, issued by the thermal insulation construction before you start to notice, transfer inspection of upper and lower operation and transfer of records. For outdoor operation, pipeline equipment to effectively carry out the insulation waterproof measures fail to install protective panels in part with three tarpaulin cover, to prevent insulation from moisture. Insulation seam Michael Jackson 5mm, joints, joints >100mm, insulation thickness tolerance (+10MM~ – 5mm), appropriate material elastic banding, spacing according to the design requirements, rigid insulation soft materials for construction joints tight; And large-diameter vertical pipe for high temperature pipeline in strict accordance with design drawings called for the establishment of expansion joints and holding bracket; Design requirements into a removable type of insulation, in strict accordance with specifications disconnect from the other insulation; Surface insulation boards in the technology of plastering construction of woven cloth to prevent pollution and protective panels flush with the surface interface, tight and clean. Site measurement of insulation boards for elbow shape cutting, ensure that each piece of lapped traffic, arc transition of natural, beautiful, screws up. Stampede outside construction personnel is strictly prohibited and shelve objects directly on the outer shield. In order to prevent the pollution-prone heater, channel area of secondary pollution of large-diameter pipes and other equipment, weaving cloth, and erection of the separation platform for preservation. Thermal insulation construction, on-hook tack welded to the consolidated line, to ensure evenly spaced, and the hook nailed down ... See next page flow chart management process. 7.2 General requirements for protective product protection 取在自己的专业领域上有所成就。 参考文献:《计算机科学概论》 人民邮电出版社 刘艺 蔡敏 编 著。 enforced thermal insulation starts checking system, issued by the thermal insulation construction before you start to notice, transfer inspection of upper and lower operation and transfer of records. For outdoor operation, pipeline equipment to effectively carry out the insulation waterproof measures fail to install protective panels in part with three tarpaulin cover, to prevent insulation from moisture. Insulation seam Michael Jackson 5mm, joints, joints >100mm, insulation thickness tolerance (+10MM~ – 5mm), appropriate material elastic banding, spacing according to the design requirements, rigid insulation soft materials for construction joints tight; And large-diameter vertical pipe for high temperature pipeline in strict accordance with design drawings called for the establishment of expansion joints and holding bracket; Design requirements into a removable type of insulation, in strict accordance with specifications disconnect from the other insulation; Surface insulation boards in the technology of plastering construction of woven cloth to prevent pollution and protective panels flush with the surface interface, tight and clean. Site measurement of insulation boards for elbow shape cutting, ensure that each piece of lapped traffic, arc transition of natural, beautiful, screws up. Stampede outside construction personnel is strictly prohibited and shelve objects directly on the outer shield. In order to prevent the pollution-prone heater, channel area of secondary pollution of large-diameter pipes and other equipment, weaving cloth, and erection of the separation platform for preservation. Thermal insulation construction, on-hook tack welded to the consolidated line, to ensure evenly spaced, and the hook nailed down ... See next page flow chart management process. 7.2 General requirements for protective product protection