計算機(jī)基礎(chǔ),全英文版的課件

1、“Introduction to Computer Science”,計算機(jī)文化基礎(chǔ),USTB Computer Department,“Introduction to Computer Science”,Class : Total 30 hours Lecture 16 hours, Lab 14 hoursGrading: Final exam 70%

2、 Others 30%Website: http://ucb.ustb.edu.cnUsername: S 學(xué)號Password: 123456Instructor : Taohong Zhang Contact: waterswordzth@163.com,,Contents,Chapter 1: Computers and Digital BasicsChapter

3、 2: Computer HardwareChapter 3: Computer SoftwareChapter 4: OSChapter 5: NetworkChapter 6: Compress,Chapter 1 Computers and digital basics,When you have completed this chapter you should be able to: Define the

4、term “computer”, “microcomputer” know the digital revolution know the history of computer development know the type of computer and function of computer Differentiate between data and information, analog and digital

5、Describe how digital devices represent numbers, text, images, and sound,master number and code. storage form of information number system and conversion of number,Section A all things digital,The DIGITAL REVOLUTIO

6、N,What is the digital revolution?The digital revolution is an ongoing process of social, political, and economic change brought by digital technology.What technologies are fueling the digital revolution?Digital electr

7、onics, computers, communications, networks, the Web, and digitizationWhat caused the sudden upswing in computer ownership?The network and the WebDigitization is the process of converting text, numbers, sound, photos a

8、nd video into data that can be processed by digital devices.,A computer network is a group of computers linked by wired or wireless technology to share data and resources.The Internet is a global computer networkThe

9、Web (short for World Wide Web) is a collection of linked documents, graphics, and sounds that can be accessed over the Internet.,Section A all things digital,Concepts:,CONVERGENCEWhat is convergence? (P.8 of E)How do

10、es convergence affect the typical consumer?Quality,Section A all things digital,DIGITAL SOCIETY,What is a computer? (Von Neumann’s definition),A computer is a multipurpose device that accepts input, process data, stor

11、es data, and produces output, all according to a series of stored instructions (P14.),Adopt binary systemStore Information,Section B Digital Devices,A computer accepts input,,“Input” :The words and symbols in a doc

12、ument, numbers for a calculation, pictures, temperatures from a thermostat, audio signals from a microphone, and instructions for completing a process;An input device gathers and translates input into a form that t

13、he computer can process.Keyboard is the main( standard ) input device,Section B Digital Devices,A computer produce output,,“output” : results produced by a computerReportsDocumentsGraphsMusic The main output de

14、vice:monitorprinter,Section B Digital Devices,A computer processes data,,data– refers to the symbols that represent facts, objects, and ideas“process data” :Performing calculations Modifying documents and pictur

15、esSorting lists of words or numbers (p15 F.1-13)Drawing graphs, A computer processes data in a device called the central processing unit (CPU),Section B Digital Devices,A computer stores data,,“Store data” : perf

16、orm automaticallyMemory - data waiting to be usedStorage - data left on a permanent basis while it is not needed for processFile - is a named collection of data that exists on a storage medium,Section B

17、 Digital Devices,computer program ---The series of instructions that tells computer how to carry out processing tasks.Software-- programs,What kind of software do computer run?System software (P. 16)Application sof

18、tware (P. 16),Section B Digital Devices,What’s so significant to store instructions,The Evolution of Computer,History1.The First Generation- Vacuum Tubes (1946-1956)（電子管）1946 ENIAC (Electronic numerical integrator

19、 and calculator) General-purpose electronic digital computer Wartime needs Decimal Programmed manually1952 EDVAC (The Von Neumann Machine) (Electronic discrete va

20、riable automatic computer) Stored-program concept Had general structure and function,The Evolution of Computer,Weight:30tStorage:80 byteSpeed:5000/s,,1950s The birth of Computer Industry

21、 Commercial Computers IBM：Series of 700/70002. The Second Generation: Transistors（1957-1964）（晶體管） 1947 Bell Labs invented transistor The late 1950s NCR, RCA Deliver the new tech

22、nology IBM 7094 Size of memory grew from 2K to 32K. Memory cycle time (the time to access one word of memory )fell from 30µs to 1.4 µs.Note: 1K = 210 =1024,The Evolution of Computer,,3. The Third

23、Generation: Integrated Circuits (1965-1971)4. Later Generations (1972-至今) Large-scale integration (LSI): >1000 components Very-large-scale integration (VLSI):>100,000 components Microprocessors: ->

24、;microcomputer(pc) All of the components of a CPU on a single chip the difference of computer and microcomputer: 1) microprocessor; 2) bus structure,The Evolution of Computer,計算機(jī)發(fā)展的四個階段,Chinese “神威” computer

25、,384 CPU384,000,000,000/sMemory size 48 GBHarddisk size 2.5TB,The Functions of Computer,Functions: Science computation Information disposal Process control Computer aided engineer (CAE) Artificial

26、intelligence (AI),The Category of Computer,Category (usage, cost, size, capability)commonly used computer categoriesMicrocomputer (personal computer)serversMainframes Supercomputers,Personal computerMicroprocessor

27、-based computing device for an individualWorkstation: Two meanings– 1. an ordinary personal computer connected to a network – 2. powerful desktop computers for high-performance tasks

28、(such as CAD),Section B Digital Devices,2. Server Serve computers on a network supplying dataClient: requests data from a server is referred to as a client,Section B Digital Devices,3. Mainframe

29、 Large, fast, expensive;Business, government;Provide centralized storage, processing and management for large amount of data;simultaneously handle thousands of users.,Section B Digital Devices,4. Superc

30、omputer ---- the fastest computers in the world Fastest, most expensive;Designed for “computer-intensive” task, such as molecular calculations, atmospheric modeling or simulating

31、 nuclear explosions,Section B Digital Devices,計算機(jī)的分類,,Data representation basic:what is data?data refers to the symbols that represent people, events, things, and ideas. data can be a name, a number, the c

32、olors in a photo, or the note in a musical composition.The difference of Data and informationdata is used by machine, such as computer; information is used by humans.,Section C. Digital Data Representation,Dig

33、ital Data Representation,Data representationthe form data is stored, processed, and transmittedAnalog and digital the difference between analog and digitalDigital data is text, number that converted into discrete dig

34、its such as 0s and 1s.Analog data is represented using an infinite scale of values.,Section C Digital Data Representation,1. Representing number,Numeric Data Numbers used in arithmetic operationsBinary number system

35、0 and 1,Section C Digital Data Representation,Computer store, process and transmit data with binary form,A computer uses a bit as the building block for more complex messages, which are constructed with a series of b

36、its. 1 bit can convey two units of information.,Section C Digital Data Representation,1. Representing number,units of binary system,1 bit 1 byte = 8 bit 1 word = 2 byte 1kB (byte) = 210 B 1MB (MegaByte)= 210 KB

37、 1GB (GigaByte)= 210 MB 1TB (Tricro) = 210 GB,Number(數(shù)制),Some Notation:,Base/ radix （基數(shù)） Digits （數(shù)字符號）Weight （位權(quán)）,,Section C Digital Data Representation,Multinomial unwrapped from the number according to the weig

38、ht:,1) The Decimal System：(4723.75)10= 4×103＋7×102＋2×101＋3×100 ＋7×10-1＋5×10-22) The Binary System： (11101. 01)2 =1×24＋1×23＋1×22＋0×21＋1×20 ＋0×2-1＋1×

39、;2-2,Section C Digital Data Representation,1. Representing number,3) The hexadecimal system Base, or radix of 16, digits (0,1,2,3,4,5,6,7,8,9, A, B, C, D, E, F) S = { . . . s2 s1 s0.s-1 s-2 s-3 . ..} S=

40、Sn－116 n－1+Sn－216n－2+…+S116 1+S0160 +S－116－1+…+S－m16－m,F1.3=15*161+1*160+3*16-1,Section C Digital Data Representation,1. Representing number,4) The octal system Base, or radix of 8 , digits (0,1,2,3,4,5,6

41、,7) S = { . . . s2 s1 s0.s-1 s-2 s-3 . ..} S=Sn－18n－1+Sn－28n－2+…+S181+S080 +S－18－1+…+S－m8－m,23.3=2*81+7*80+3*8-1,83= ?,Section C Digital Data Representation,,1) Conversion between Binary and Decima

42、l To convert from decimal to binary, the integer and fractional parts are handled separately.,Number Conversion,,a) Convert decimal integer N into binary form: N =(1 ×2k) + (Rk × 2k-1) + .. . + (R3 ×

43、 22) + (R2 × 21) + (R1 ×20) Repeated divisionEx. Decimal 11 Quotient Remainder11/2 = 5 15/2 = 2 12/2 = 1 01/2 = 0 1,,,,,,,,,Number Conversion,1,0,1,

44、1,(11)10= (1011)2,b) Fractional part involved repeated multiplication. F = (a-1× 1/2)+( a-2× 1/22)+( a-3× 1/23)+... This process is not necessarily exact. Ex. Decimal 0.81 Product Inte

45、gral Part .1 1 0 0 1 10.81 × 2 = 1.6210.62 × 2 = 1.2410.24 × 2 = 0.4800.48 × 2 = 0.9600.96 × 2 = 1.9210.92 × 2 = 1.841,

46、,,,,,,,,,,,,(0.81)10= (0.110011)2, (approximate),,Ex. Decimal 0.25 Product Integral part 0.25×2 = 0.5 0 0.50×2 = 1.0 1 0.2510 = 0.01 (exact),,,,,0 1,,2) Con

47、version between Hexadecimal and DecimalBase 16 (0,1,2,3,4,5,6,7,8,9,A,B,C,D,E,F)0000=0 1000=80001=1 1001=90010=2 1010=A0011=3

48、 1011=B0100=4 1100=C0101=5 1101=D0110=6 1110=E0111=7 1111=FHexadecimal DecimalEx.1A16 = (116× 161)

49、+( A16× 160) = (110× 161)+( 1010× 160) = 26 Binary Hexadecimal 1101 1110 0001 = DE116 D E 1,,,,3) Conversion between Octal and DecimalBase 8

50、(0,1,2,3,4,5,6,7)000=0 001=1 010=2 011=3 100=4 101=5 110=6

51、 111=7 Octal DecimalEx. 178 = (18× 81)+( 78× 80) = (8)+ (7) = 15 Binary Octal 101 111 001 = 5718

52、 5 7 1,,,整型數(shù)的存儲,機(jī)器數(shù)：將一個數(shù)在機(jī)器中的存儲形式（即編碼）稱為機(jī)器數(shù)。在計算機(jī)中帶符號整數(shù)是采用補(bǔ)碼表示的 帶符號數(shù)的最高位用來表示數(shù)的符號，一般用“0”表示“+”，用“1”表示“-”。,1 . 機(jī)器數(shù)與真值,# of Bits ---------816,Range-------------------------------------0

53、 2550 65,535,整型數(shù)的原碼、反碼和補(bǔ)碼正數(shù)：原碼、反碼、補(bǔ)碼相同。 符號位為0，數(shù)值為對應(yīng)的二進(jìn)制數(shù)。例如：＋109 [＋109]原 = [＋109]反 = [＋109]補(bǔ)= 01101101,原碼：符號位為1，數(shù)值為絕對值的二進(jìn)制數(shù)。 例：[-109]原=11101101反碼：將原碼除符號位

54、外，逐位取反。 例：[-109]反= 10010010補(bǔ)碼：將反碼末位加1。 例：[-109]補(bǔ)=10010011,負(fù)數(shù)：,Arithmetic and Logic Rule,,Example of Arithmetic and Logic,ex3：a = 1100，b = 0110 a∨b、a∧b、ˉa 1100 1100 1100

55、 ∨ 0110 ∧ 0110 邏輯非為： 1110 0100 0011,,ex1： 101. 01 +110. 01 1011. 10,ex2： 101. 111 + 11. 011 1001. 010,2. Represent

56、ing symbols,How to denote character? a) ASCII coding （ American Standard Code for Information Interchange）,uses 7 bits to represent 27 Symbols (128 symbols), including uppercase and lowercase letters, special co

57、ntrol codes, numerals, and punctuation symbols.,Section C Digital Data Representation,ASCII Rule,One byte (8 bits binary code) represents one character,,The top of byte is “0”,The others(7 bits) can have 128 binary code

58、s. Ex ：0000 0000-0111 1111Represent 128 characters.,Section C Digital Data Representation,ASCII Rule,,,,A為（0100 0001）2 = 65,,記?。?字符的ASCII碼是48A字符的ASCII碼是65a字符的ASCII碼是97a與A 的ASCII碼之差是32,b) Chinese code: GB-2312,《信息

59、交換用漢字編碼字符集——基本集》/ GB2312-80 7445 Chinese and graph symbol： common：202； sequence：60； number：22； English：52；Japan：169； Greek：48; Russia：66 Chinese：6763；(3755；3008)Two bytes represent each Chines

60、e or symbol.,Section C Digital Data Representation,高八位,低八位,例如：“啊” 的國標(biāo)碼為(3021)16 “住” …… (5721)16,漢字的編碼,各種代碼之間的關(guān)系：,包括：信息交換碼（國標(biāo)碼）、機(jī)內(nèi)碼、輸入碼和輸出碼機(jī)內(nèi)碼（亦稱內(nèi)碼）：漢字（符號）在計算機(jī)內(nèi)部的二進(jìn)制代碼。,輸入碼（外碼）,輸入碼：漢字輸入時使用的編碼。,例如： “國” 的輸入碼全拼

61、：guo；五筆字形碼：lgy；區(qū)位碼：2590,典型的輸入碼有：全拼、五筆字形、微軟輸入法、智能ABC輸入法、搜狗拼音輸入法、區(qū)位碼等。,輸入碼不唯一！,輸出碼（字模、字型碼）,輸出碼：漢字輸出時使用的編碼。以點陣形式表示。如16×16點陣、24×24點陣、32×32點陣等一個16×16點陣漢字輸出碼所占存儲空間： 16/8×16=32個字節(jié),16x16點陣漢字及編碼,24x24

62、點陣漢字,32x32點陣漢字,Difference:1. Image quality;2. The amount required to store the image;3. The amount of time required to transmit the image4. How easy to modify the image and so on,3. Representing Images,Section C Dig

63、ital Data Representation,Bitmap graphic method of a black-and-white image – monochrome graphic1 pixel can be represented by 1 bit.,Grayscale graphics,Grayscale graphic: display a bitmap image using shades of gray or “

64、gray classes” (black and white photos)256-grayscale graphic,1 pixel can be represented by 8 bits.,A full screen 256-grayscale graphic at 640 * 480 resolution requires 307,200 bytes.,Color graphics,Color graphic: displa

65、y a bitmap image using color,16 color : 1 pixel can have 16 color, need 4 bits,256 color:1 pixel can have 256 color, need 8 bits,16.7 million colors (24-bit or true-color graphic) color: need 3 bytes to present

66、 : Red Green Blue,width：271height：300color：2size：9.9 KB,width：271height：300color：4size：19.8 KB,Example of graph,Section C Digital Data Representation,width：271height：300color：256size：79.4 KB,width：271height：30

67、0color：true colorsize：238.2 KB,Example of graph,Section C Digital Data Representation,Computation for storage,To store a true color image resolution 352×288Color byte 3Bstorage= 352×288 ×3=297KBIf e

68、nhance image resolutionstorage= 768×1024 ×3=2.25MB,Decrease the graphic storage and transmission time,Approximator: Making an image physically smaller by shrinking it or cropping it will decrease the number o

69、f pixels required to represent the graphic. Compression: Size of graphic file can be reduced by technique known as compressionDithering: reduce the number of colors in a graphic.,Vector graphic and Digital Video,Vector

70、 graphicDifference between vector graphic and bitmap graphic?vector graphic: consist of a set of instructions that recreates a picture.You can use vector graphics software to draw a picture, CIRCLE 40 Y200 150 means

71、: create a circle with 40 pixels radius, color it yellow, and place the center of the circle 200 pixels from the left of the screen and 150 pixels from the top of the screenDigital videoComposed of a series of frames.