1 / 41

Seeram Chapter 2: Introduction to Computers

CT. Seeram Chapter 2: Introduction to Computers. Electronic Computer Technology. Vacuum tubes Discrete Semiconductors Integrated Circuits. Early Computers . 1951-1958 Vacuum tube memory Input / Output Punch cards Magnetic Tape. Electronic Computer Technology. Vacuum Tubes. Warm-up

satya
Download Presentation

Seeram Chapter 2: Introduction to Computers

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. CT Seeram Chapter 2: Introduction to Computers

  2. Electronic Computer Technology • Vacuum tubes • Discrete Semiconductors • Integrated Circuits

  3. Early Computers • 1951-1958 • Vacuum tube memory • Input / Output • Punch cards • Magnetic Tape

  4. Electronic Computer Technology Vacuum Tubes • Warm-up • Ran hot • tube filaments required constant heating • computers required air conditioning • Frequent failures

  5. Computers after Vacuum Tubes • 1959-1963 • Transistor & magnetic core memory • Smaller • Less power needed

  6. Discrete Semiconductor Components in Computers • transistors • magnetic memory cores • Space requirements • large but • smaller than vacuum tubes • Ran much cooler than vacuum tubes

  7. Computers: The Big JumpIntegrated Circuits • millions of semiconductor components in tiny package • lower production costs • Extremely small • Extremely fast • Run very cool • Very reliable

  8. Categories of Computers • Super computers • Mainframes • Minicomputers • Microcomputers

  9. 5th Generation: Supercomputers • Large (even today) • Expensive • Found only in major research sites • Applications • weather • scientific modeling • oil exploration • other research

  10. Mainframe Computers • Large • $$$ • Requires teams of experts • Large # of users • Applications • large corporations • government • hospitals

  11. Microcomputer • “PC” • Rapidly changing technology • Low cost • Non-proprietary • First common in 1980’s

  12. Minicomputers • First seen in 1970’s • Much less expensive than mainframes • Medium-sized • Proprietary ($$$) • parts • operating systems • Computer used for CT • Appropriate • Size • price • Applications • imaging, reconstruction • archiving

  13. Basics Input Processing Output

  14. Input • Other • Voice recognition • Manual • keyboard • mouse • Electronic • CT detectors • CR Plates Input Processing Output

  15. Analog to Digital Conversion(A to D) Analog (continuously varying) Digital (discretely varying)

  16. Analog to Digital Conversion(A to D) • Many real world inputs are analog voltages • CT detector intensity • Analog values must be converted to a # to use in a computer 0.8 0.6 Input analog voltage 0.4 0.2 Digital conversion to computer 1 2 3 4

  17. Processing • Central Processing Unit (CPU) • Arithmetic • Logic • Internal Memory • Scratchpad Input Processing Output

  18. Output • Storage • disk • tape • Hard copy • printer • Soft copy • CRT Input Processing Output

  19. Hardcopy Devices • Do not lose information when power is shut off • Printers • impact (dot matrix) • noisy • multi-copy • non-impact (quiet) • ink jet • laser • Plotters • Microfilm

  20. Softcopy Devices • Lose all information when power shut off • Flat-panel monitors

  21. 125 25 311 111 182 222 176 199 192 85 69 133 149 112 77 103 118 139 154 125 120 145 301 256 223 287 256 225 178 322 325 299 353 333 300 Digital to Analog Conversion(D to A) • Computer reconstructs digital image • set of numbers • Computer displays analog image

  22. Computer System Elements Hardware Software People

  23. Hardware Hardware can be seen. • Computer • Peripherals • keyboard • printer Hardware can be touched. Hardware Software People

  24. HardwareExamples • Disk Drive • Memory • Random Access (RAM) • Read only (ROM) • Mouse • Keyboard • Cables Hardware Software People

  25. Software • Instructions to computer • Operating System • Applications Hardware Software People

  26. Operating System • Fundamental instructions to hardware • What to do when computer first turned on • How to interact with hardware • CRT • Keyboard • Mouse • Modem Hardware Software People

  27. Operating System • Computer “face” presented to users • Windows • DOS • MAC OS • Dictates how usersinteract withcomputer torun applicationsoftware Hardware Software People

  28. Application Software • Computer instructions which perform some desired task • Balance checkbook • Play a game • Calculate (reconstruct)a CT image Hardware Software People

  29. Application Software Forms![FDoSurvey]![FExpsSub].Form![KVEff] = Val(Mid$(MyData, 2, 10)) Forms![FDoSurvey]![FExpsSub].Form![KVAVG] = Val(Mid$(MyData, 12, 10)) Forms![FDoSurvey]![FExpsSub].Form![MRMEAS] = Val(Mid$(MyData, 22, 10)) Forms![FDoSurvey]![FExpsSub].Form![TIMEMEAS] = Val(Mid$(MyData, 32, 10)) DumText = Mid$(MyData, 42, 3) 'MsgBox$ (DumText) If Right$(DumText, 1) = "+" Then DumText = Left$(DumText, 2) Else DumText = Left$(DumText, 1) End If 'MsgBox (DumText) MyData = Right$(MyData, Len(MyData) - Len(DumText) - 41) 'MsgBox (MyData) NKvs = Val(DumText) 'MsgBox (NKvs) KVMAX = 0 If NKvs > 0 Then For DumNum = 1 To NKvs 'MsgBox (Val(Mid$(MyData, 10 * (DumNum - 1) + 1, 10))) If (Val(Mid$(MyData, 10 * (DumNum - 1) + 1, 10))) > KVMAX Then KVMAX = (Val(Mid$(MyData, 10 * (DumNum - 1) + 1, 10))) End If Next Forms![FDoSurvey]![FExpsSub].Form![KVMAX] = KVMAX End If DoCmd.Close acForm, "FNeroExp" End Sub • Usually a quasi-English language • Basic • Fortran • COBOL • C • Languages provide tools to software developers to efficiently design application software

  30. People • Designers • hardware • software • Users • run applications • provide input • use output These parties do not always communicate

  31. Meaningless Slide

  32. Storage HardwareRandom vs. Sequential • Direct (random) access • any data can be accessed at any time • disks • Sequential access • data only accessed in serial fashion • must pass through unwanted data to reach target data • tapes • information encoded magnetically

  33. Data Storage Technologies(constantly changing) • Technologies • Magnetic (disks & tape) • re-writable • optical (disks & CD’s) • re-writable • write once • Disks • Formats • Hard • removable • non-removable • Floppy • CD • CD-RW • CD-R • Tape • lots of data • serial access

  34. Data Communication • Data transmission between computers • Features • speed • cost • topology • wiring scheme

  35. Data Communication Technologies • Telephone lines • twisted pair wires • Coaxial cable • Fiber optic cable • Microwaves • Satellites • Radio waves

  36. Networks • LAN (Local area network) • computers connected in one area • LAN’s can be connected together • WAN (Wide area network) • computers connected together over large distances • Communications protocols • Ethernet • uses bus technology • Internet

  37. File Server • Special computer which handles functions for connected computers • disk access • printing • Incorporates security • may limit user to selected files or directories • may limit # of connections per user • may limit times when network available

  38. Typical Lan Network Gateway Other Networks

  39. Radiology Computer Systems Hospital Admission/Discharge Billing Reports Insurance Carrier Voice to Text Dictation PACS Digital Spot Film RIS Web Server Digital Dictation Professional Billing Angio / Digital Subtraction CT Mammography MRI CR

  40. The Computerization of Radiology Nuc Med Digital Fluoro Digital Angio CT CR MRI Web Browser 3D Workstation Laser Printer RIS PACS Dictation Admin Radiologist Workstation Radiologist Workstation Radiologist Workstation

  41. The Internet • Network connecting all computers • Originally developed for security • Single bomb can’t destroy all U.S. computing facilities • Can connect large number of computers in many locations • Communicates in finite “packets” • Each packet has specific destination (address) • Packets can be • E-mail • Web site • Allows linking of information

More Related