Information Processing

Transcription

1 Infrmatin Prcessing Main Aims f the Unit: This unit describes the main elements in the prcessing f data. These include input, utput and data checking. The rle f the main prcessr (CPU) is described and different types f sftware are explred. Varius appraches t file rganisatin are cnsidered and the imprtance f security in the user-interface is stressed. Main Tpics f Study: A. Intrductin 1. Definitins f hardware, sftware, package, prgram, data, parameter. 2. Overview f the range f cmputers currently used frm lap-tp t supercmputer, 3. Cnfiguratin diagram shwing hw the cmpnents f a cmputer system are related. Difference between cntrl signal and data flw. B. Input 1. Review f methds f data capture t include OCR, OMR, MICR, barcdes, text/image scanners, magnetic stripe, vice, tuch screen, keybard, and cncept keybard. 2. Advantages and disadvantages f these methds f data capture when cmpared with thers. In particular, a cmparisn f speeds, csts, user invlvement, accuracy f the data received by the cmputer. 3. Chse the best data capture methd fr a given applicatin. 4. Cnditins required fr each f these data capture devices t be used. A detailed explanatin f the internal peratin is NOT required. C. Data checking 1. Difference between Validatin and Verificatin. 2. Validatin checks - range, data type, presence, sequence, 3. Specifying the validatin pssible fr a GIVEN SET OF DATA. 4. Check digit systems - nrmally using mdul-11 and weights 6,5,4,3,2,1 etc. Specify WHICH data can/shuld cntain check digits. State the guarantees that check digit numbers prvide. Calculate the check digit fr a given number Validate a number which cntains a check digit. The use f X as a check digit. D. Output 1. Ways in which data can be represented - tables, lists, summary statistics, charts, textual reprts. 2. Name the range f printers currently available - laser, ink jet 3. Advantages and disadvantages f different types f printers. 4. Screen utput. Its limitatins. 5. Identifying whether screen r printer wuld be mre suitable fr a given applicatin. 6. Types f pltters currently available. Cmparisn with printers. 7. Identifying whether a printer r pltter wuld be mre suitable fr a given applicatin. 8. Other frms f utput. COM. Micrfiche. Applicatins where these might be used. E. Prcessr 1. Cmpnent parts f the CPU and their functins - ALU, Cntrl unit. 2. MAIN memry and its varius frms - RAM, ROM, cache, special purpse RAM e.g. fr VDU 3. Name registers in general use - accumulatr(s), prgram cunter (PC), Memry address (MAR), Memry data/buffer (MDR/MBR), Current instructin (CIR). 4. Fetch-execute cycle. Name the steps an instructin passes thrugh in the cycle. Identify hw the registers are used fr basic instructins. e.g. LDA Price, SUB Tax. This tpic MUST be cvered in detail. 5. Bus structures. F. Sftware 1. Distinctin between system sftware and applicatin sftware. 2. Distinctin between general purpse and special purpse sftware. Understand that the USER dictates hw general purpse sftware is used. 3. Outline f features f perating systems including systems with multiprgramming facilities. Name different perating systems currently in use and cmpare in utline. 4. System sftware. File management sftware. Utility sftware. Srt file. Merge files. Language translatrs. Assembler, cmpiler, interpreter - basic differences. G. Filing systems 1. Review f current strage devices - diskette, hard disc, Winchester, flash drive/pen stick, ptical devices, digital versatile disk, tape and cassette 2. The need fr buffers and their rle in data transfer. 3. Definitins f strage terms - file, recrd, field, cylinder, track, sectr, header label, inter-blck gap. Distinctin between strage device and strage medium. 4. The structure f data stred n a strage medium.

2 5. Data transfer checks. Parity and its purpse. Describe dd/even parity with specific numeric examples illustrating acceptance/failure. Cyclic redundancy check. 6. File Organisatin and File Access Define rganisatin types - serial, sequential, indexed sequential, randm. Distinctin between rganisatin and access. Examples f a file being accessed in mre than neway. Fr indexed sequential rganisatins - an understanding f up t 2-levels f indexing. Appreciatin that nt all recrd keys appear in the index. Hw ANY recrd can be accessed. Overflw areas. Fr randm access - hashing algrithms. Develp a simple algrithm fr a given situatin. Fr each f the fur rganisatin methds, describe the PROGRAM sequence f steps t: a. access a SINGLE recrd frm the file b. add a new recrd t the file c. delete a recrd frm the file. 7. Sequential master file update using an UNSORTED transactin file. Labelled system flw chart fr this prcess. 8. Selecting the mst apprpriate file rganisatin fr a given applicatin. H. Prcessing 1. Different types f prcessing batch and real-time. 2. The rle f batch prcessing with tday s sphisticated systems. Examples f batch prcessing currently in use. 3. Real-time systems examples f current use. I. Security and privacy 1. Security defined as the safeguard f hardware, sftware and data. 2. Distinctin between security and privacy. 3. REALISTIC methds f data security securing against accidental damage r lss f data deliberate sabtage. 4. Methds f achieving gd privacy f data. 5. Determining the security/privacy required fr a given situatin. Learning Outcmes fr the Unit: At the end f this Unit, students will be able t: 1. Describe the main cnfiguratin f a cmputer systems including input, utput and prcessr 2. Identify different types f sftware including system and applicatin sftware 3. Distinguish between different filing and prcessing systems 4. Understand the users rle in data security The numbers belw shw which f the abve mdule learning utcmes are related t particular cgnitive and key skills: Knwledge & Understanding 1-4 Analysis 4 Synthesis/Creativity - Evaluatin 3 Interactive & grup Skills - Self-appraisal/Reflectin n Practice - Planning and Management f Learning - Prblem Slving - Cmmunicatin & Presentatin - Other skills (please specify) - Learning and teaching methds/strategies used t enable the achievement f learning utcmes: Learning takes place n a number f levels thrugh lectures, class discussin including prblem review and analysis. Frmal lectures prvide a fundatin f infrmatin n which the student builds thrugh directed learning and self managed learning utside f the class. The students are actively encuraged t frm study grups t discuss curse material which fsters a greater depth learning experience. Assessment methds weightings which enable students t demnstrate the learning utcmes f the Unit: 3 hur examinatin: 100% (Chse any 5 questins frm 8. Each questin is wrth 20% f the marks. ) Indicative Reading fr this Unit: Main text Refer t the ICM website fr learning material Alternative texts & Further Reading: Cmputer Science fr Advanced Level by R Bradley - (Stanley Thrnes) ISBN (Furth editin). A Level Cmputing by PM Heathcte & S Langfield - (Payne Gallway) ISBN (Fifth editin) Guideline fr Teaching and Learning Time (10 hurs per credit) Lectures / Seminars / Tutrials / Wrkshps: 50 hurs Tutrial supprt includes feedback n assignments and may vary by cllege accrding t lcal needs and wishes. Directed learning: 50 hurs Advance reading and preparatin / Class preparatin / Backgrund reading / Grup study / Prtfli / Diary etc Self managed learning: 100 hurs Wrking thrugh the curse text and cmpleting assignments as required will take up the bulk f the learning time. In additin students are expected t engage with the tutr and ther students and t undertake further reading using the web and/r libraries.

3 MARCH 2011 INFORMATION PROCESSING (NEW) Instructins t candidates: a) Time allwed: Three hurs (plus an extra ten minutes reading time at the start d nt write anything during this time) b) Answer any FIVE questins c) All questins carry equal marks. Marks fr each questin are shwn in [ ] d) Mark allcatins are shwn in [ ] and shuld determine the length and depth f yur answer and the time yu spend n it. A part questin carrying 4 marks nrmally requires 4 different and valid pints e) In definitins, d nt use the wrd being defined in yur definitin e.g. avid the wrd SERIAL when defining SERIAL FILE f) Ensure that yu pay particular attentin t wrds underlined, in CAPITALS r in bld. FEW OR NO MARKS will be awarded t any questin where these are ignred g) N cmputer equipment, bks r ntes may be used in this examinatin 1. Read the whle questin befre starting this ne. Select a particular cmpany r rganisatin that yu have studied. a) State the name f the cmpany and its main functins. [2] b) Describe ALL the uses f cmputing in this cmpany. Indicate the type f prcessing in EACH case. [5] c) Describe the specific utputs that cmputers prduce in the cmpany and explain wh uses these and hw they are used. [5] d) List the hardware used in the main applicatins f the cmpany including the number and types f cmputers used. [5] e) Describe the input data needed t prduce the results. [3] 2. a) i The PC is incremented during a fetch-execute cycle. Explain what this means and WHY it happens. [2] ii In the diagram belw, A t D represents the sequence f events ver ne fetch-execute cycle. A FETCH B C EXECUTE D time State at which f the times A, B, C r D will the PC be incremented. [1] iii The PC culd be altered at anther time during the cycle. State the circumstances when this happens and at which pint in the cycle (A, B, C and D) it ccurs. [2] b) Memry lcatin 4567 hlds the variable X and lcatin 4568 hlds the variable Y. Referring t the fetch-execute cycle, describe IN DETAIL the sequence f events that ccurs when the value X Y is calculated and the result returned t memry lcatin R (4569). The prgram rutine fr this begins in lcatin Shw hw the registers change thrughut. [15] 3. a) In business, a cmputer user may use tw types f applicatin sftware general purpse and special purpse. i Distinguish between the tw. ii An emplyee uses a special-purpse package. Explain hw his subsequent actins will be different frm using a general-purpse package. [5] b) A user wishes t srt a very large data file f emplyee recrds (key field = emplyee number) s that the file is srted by emplyee name surname must be the prime key and first name the secndary key. State the infrmatin the srt prgram will need t achieve this. [5] c) Name a particular perating system. Describe FIVE majr features the perating system prvides. Yur chices must be significantly different frm each ther. [10] 4. a) Outline the pssible effects f a cmpany with inadequate security in its cmputer system. [4] b) Discuss pssible ways in which a cmputer system culd be vulnerable and suggest ways f eliminating r minimising EACH. Yur answer shuld cnsider: i accidental lss f data ii hardware prblems iii deliberate acts t create prblems by staff r ther peple [16] 5. Write ntes abut FIVE f the fllwing. Each f yur answers must have at least FOUR different and significant pints. a) Cmparisn between the speeds f input, utput, strage devices and memry b) Minicmputers c) Batch prcessing d) Pltters e) Distinctin between special purpse and general purpse sftware f) Spling [4 each] 6. Chse any FOUR f the fllwing methds f data capture. Fr EACH: describe hw the data input device wrks using apprpriate diagrams identify precisely a particular applicatin that is mst suited t its use a) Barcde reading b) MICR c) OCR

4 d) OMR e) Vice recgnitin [5 each] 7. a) Explain why there are s many different types f printers. [4] b) Name FOUR specific types f printer. [4] c) Select any TWO f these printers. Fr EACH: i briefly describe an apprpriate applicatin which wuld need it ii describe its characteristics which distinguish it frm ther printers [6 each] 8. Name a particular perating system and describe, in detail, FIVE significantly different tasks that it perfrms. [4 each]

5 JUNE 2011 INFORMATION PROCESSING (NEW) Instructins t candidates: a) Time allwed: Three hurs (plus an extra ten minutes reading time at the start d nt write anything during this time) b) Answer any FIVE questins c) All questins carry equal marks. Marks fr each questin are shwn in [ ] d) Mark allcatins shuld determine the length and depth f yur answer and the time yu spend n it. A part questin carrying 4 marks nrmally requires 4 different and valid pints e) In definitins, d nt use the wrd being defined in yur definitin e.g. avid the wrd SERIAL when defining SERIAL FILE f) Ensure that yu pay particular attentin t wrds underlined, in CAPITALS r in bld. FEW OR NO MARKS will be awarded t any questin where these are ignred g) N cmputer equipment, bks r ntes may be used in this examinatin 1. a) Define the term OMR. Explain, in general terms, hw OMR perates. [5] b) Chse THREE different majr applicatin uses f OMR and fr EACH: i name the applicatin ii explain hw the rganisatin using it will prepare fr its use iii explain wh will be the target data suppliers and hw this data is cllected iv describe what the rganisatin will d nce the data has been cllected [5 each] 2. a) Check digit validatin cannt realistically be used fr checking all numeric data. Identify a situatin where it is apprpriate and ne in which it is nt. [2] b) Emplyee numbers are six digits lng and are created using the mdul-11 system with traditinal weights 6, 5, 4, 3, 2, 1. Investigate the number and state whether it is valid r nt. Shw all stages f yur wrking. [6] c) Give specific BUSINESS examples where EACH f the fllwing validatin checks wuld be used. Include in yur answer fr EACH: tw realistic examples f data ne VALID and ne INVALID explanatin f hw the cmputer culd detect the invalid ne i range check ii frmat check iii presence check iv any ther check (excluding check digit verificatin) [12] 3. A cmpany hlds details f all its prducts n an indexed-sequentially rganised file. In a telephne enquiry, a custmer asks fr details abut prduct The prduct file is then accessed directly. a) Describe all the internal prcesses, lgical and mechanical, that ccur frm the mment 3456 is keyed until the details f the prduct appear n the screen. [10] b) Explain why the file is unlikely t be held n CD-ROM. [2] c) The file wuld nt be held n magnetic tape. Explain why magnetic tape is still used fr ther purpses. [3] d) Using the fllwing table, add FIVE mre fields that yu wuld expect t find n this PRODUCT file. [5] Field Name Datatype Purpse hw it is used PrductName Character Identificatin and fr printing n a custmer invice 4. a) Distinguish CLEARLY between SYSTEM sftware and APPLICATION sftware. [2] b) Prgram surce cde must be translated in rder t run n a cmputer. Discuss the THREE main types f language translatrs available, distinguishing carefully between them. [9] c) Discuss IN DEPTH a SPECIAL-PURPOSE business APPLICATION package yu have studied. In particular: i name the area f business it cvers ii identify wh the main users are iii state its main functins iv describe the type f data that is input v describe the utputs that it prduces [9] 5. Select TWO f the fllwing methds f data capture: a) MICR b) OCR c) OMR d) Barcde reading Fr EACH: i state a typical applicatin which uses that methd ii describe the frmat f the data befre input iii describe hw the apprpriate input device wrks frm the cmputer pint f view iv explain why it is the MOST apprpriate methd fr that particular applicatin [10 each]

6 6. a) In table frm, list FIVE pssible causes f hardware failure and state ways f minimising r eliminating EACH. [10] b) In table frm, list FIVE pssible cause f data lss ther than hardware failure. Again, state ways f minimising r eliminating EACH. [10] 7. Chse FOUR different types f printers. Fr EACH ne: describe briefly the internal wrkings give ONE typical applicatin fr which it is MOST apprpriate [5 each] 8. a) A cmpany receives 500 rders per week thrugh the mail fr items which are nt urgent and as a result BATCH PROCESSING is used. i Explain what happens in batch prcessing. Describe als hw BATCH TOTALS wuld be used and hw they are calculated. [6] ii Explain hw errrs detected in data submitted fr batch prcessing are crrected. [4] iii There is nw far less batch prcessing than in the past. Explain why. [2] b) i Identify the files that wuld be needed in THIS batch prcessing example. [2] ii Draw a labelled systems diagram t shw hw these files wuld be used during the batch prcessing update. Describe briefly the varius stages that ccur in the prcess. [6]

7 SEPTEMBER 2011 INFORMATION PROCESSING (NEW) Instructins t candidates: a) Time allwed: Three hurs (plus an extra ten minutes reading time at the start d nt write anything during this time) b) Answer any FIVE questins c) All questins carry equal marks. Marks fr each questin are shwn in [ ] d) Mark allcatins shuld determine the length and depth f yur answer and the time yu spend n it. A part questin carrying 4 marks nrmally requires 4 different and valid pints e) In definitins, d nt use the wrd being defined in yur definitin e.g. avid the wrd SERIAL when defining SERIAL FILE f) Ensure that yu pay particular attentin t wrds underlined, in CAPITALS r in bld. FEW OR NO MARKS will be awarded t any questin where these are ignred g) N cmputer equipment, bks r ntes may be used in this examinatin 1. a) A file-handling prgram might cntain a cmmand t read a single recrd int a prgram buffer. i Describe all the steps, lgical and physical, which take place t execute this cmmand if the file has INDEXED-SEQUENTIAL rganisatin. [6] ii Repeat this fr a file rganised as RANDOM. [4] b) It is unusual t amend a SINGLE recrd n a file with SERIAL rganisatin. Hwever, it is realistic fr small files. Describe in full hw a single recrd can be changed withut altering r lsing any f the ther recrds i s that a new file is created [5] ii s that the SAME file area is used fr the updated versin [5] 2. a) Distinguish carefully between the terms validatin and verificatin. [4] b) State fully the purpse f validatin. [4] c) When a new emplyee jins a cmpany, a recrd is placed n the emplyee file. Sme f the fields are: Fieldname Datatype Typical data Surname Character (20) Smith EmplyeeID Integer AnnualSalary Real JbTitle Character (20) Warehuse clerk DateOfBirth Date EmplymentDate Date Cnsider EACH FIELD IN TURN and identify the validatin that can be perfrmed by the data input prgram n that field. [12] 3. a) Draw a labelled diagram shwing the cmpnent parts f the central prcessr. Omit cntrl signals but shw directins f data flw using arrws. [6] b) Distinguish clearly between a laptp and a desktp cmputer. [4] c) Describe the steps in the fetch-execute cycle which wuld be undertaken when the instructin in memry during the run is ADD X,M. Take this t mean that the cntents f address M are added t register X. [10] 4. a) Printers used with large netwrks have different characteristics frm thse nrmally attached t micrcmputers. Explain what these are. [5] b) Select a printer suitable fr printing invices which will be handed t custmers f a car hire cmpany when they reserve their cars. Explain why it is suitable and describe its methd f printing. [7] c) Select a different type f printer suitable fr printing tax statements t be sent t ver ne millin custmers. i Explain why it is suitable and describe its methd f printing. ii Explain why the chices yu have made in each f b) and c) wuld nt be suitable fr the ther. [8] 5. a) Distinguish clearly between SECURITY and PRIVACY. [4] b) Describe the measures that MUST be taken t ensure that PRIVACY is guaranteed in a large rganisatin with regards t cmputerised data. [10] c) Identify SIX significantly different measures that culd be taken t ensure that data is SECURE. [6] 6. a) With the aid f a diagram, explain hw a pltter is able t print diagrams in different clurs and with assciated text f different fnts, fnt sizes and at different inclinatins. [8] b) Mdern printers can print diagrams with included text. Describe applicatins frm the wrld f cmmerce and industry where diagrams are prduced and where: a pltter wuld be MORE apprpriate [4] a printer wuld be MORE apprpriate [4] Yur answers shuld explain why EACH is mre apprpriate. Identify: i TWO types f printers which are able t print gd quality diagrams and ii TWO printers which either cannt print diagrams r the quality is pr [4] 7. Name a particular perating system and describe, in detail, FIVE significantly different tasks that it perfrms. [4 each]

8 8. a) Describe the differences between high- and lw-level languages, illustrating yur answer with brief examples f cding. Discuss the differences during the prcesses f writing a prgram crrecting prgram errrs translating a prgram run-time [10] b) Define the term UTILITY prgram. Give TWO examples f utility prgrams, explaining what EACH achieves. [5] c) Briefly describe FIVE significantly different features f an perating system. Yur examples can be frm different types f perating systems prvided yu indicate which type.

9 DECEMBER 2011 INFORMATION PROCESSING (NEW) Instructins t candidates: a) Time allwed: Three hurs (plus an extra ten minutes reading time at the start d nt write anything during this time) b) Answer any FIVE questins c) All questins carry equal marks. Marks fr each questin are shwn in [ ] d) Mark allcatins shuld determine the length and depth f yur answer and the time yu spend n it. A part questin carrying 4 marks nrmally requires 4 different and valid pints e) In definitins, d nt use the wrd being defined in yur definitin e.g. avid the wrd SERIAL when defining SERIAL FILE f) Ensure that yu pay particular attentin t wrds underlined, in CAPITALS r in bld. FEW OR NO MARKS will be awarded t any questin where these are ignred g) N cmputer equipment, bks r ntes may be used in this examinatin 1. All parts f this questin relate t a retail cmpany. a) Explain why validatin is perfrmed when data is first input. [2] b) Part f a recrd fr a current sales transactin is shwn belw: Purchaser Quantity Date f purchase William Blake /5/2010 Take EACH f the three fields in turn and describe the validatin that can be undertaken. [8] c) Prduct cdes are six digits lng and use a traditinal check digit system. The mdul-11 methd is used with weights f i William Blake rders prduct Explain hw this number can be checked WITHOUT the need t refer t the prduct file. Prve that this prduct number is valid, shwing all wrking and explaining the steps. [5] ii Explain why the next prduct number in sequence CANNOT be [2] iii Calculate the next prduct number in sequence after Again, shw all yur wrking. [3] 2. The table belw shws the cntents f part f memry at a given time during the running f a prgram. The cntents are shwn in their mst cnvenient frms but are f curse held in binary. ADDRESS CONTENTS MEANING Stre lcatin P 4100 SUB P Subtract cntents f P frm accumulatr 4101 BPZ G If cntent f accumulatr is psitive r zer, branch t G 6123 STP Lcatin G. STOP. End the prgram Value f Prgram Cunter (PC) = 4100 Cntents f accumulatr = 8500 Describe IN DETAIL: the events that ccur during the next TWO fetch-execute cycles and the cntents f registers as they change the purpse f EACH register the first time yu refer t it [20] 3, a) Explain why there are s many different types f printers. [4] b) Name FOUR specific types f printer. [4] c) Select any TWO f these printers. Fr EACH: i briefly describe an apprpriate applicatin which wuld need it ii describe its characteristics which distinguish it frm ther printers [6 each] 4. A cmpany hlds its 8000 prduct RECORDS n its prduct file. This MASTER file is rganised as SEQUENTIAL using prduct number as the KEY field. On the file are details f prducts numbered 4567, 5678, 6789 and a) Define carefully the FOUR terms abve in CAPITAL letters. [8] b) A single new prduct (prduct number 7000) is t be added t this file. A prgram is available t d this. Describe carefully the steps this PROGRAM will take. [4] c) Unaware that the prduct has already been added t the file, a different stck cntrller als tries t add 7000 t the file. Describe the features needed in the PROGRAM t handle the prblem this culd cause. [2] d) The SINGLE prduct 6789 is being discntinued and shuld be remved frm the stck file. Again, a prgram is available t d this. Describe the steps this PROGRAM takes. [4] e) Explain what data wuld need t be held n file fr each prduct s that a prgram run culd print a list f thse prducts which need rerdering because they are running lw. [2] 5. a) Outline the pssible effects f a cmpany with inadequate security in its cmputer system. [4] b) Discuss pssible ways in which a cmputer system culd be vulnerable and suggest ways f eliminating r minimising EACH. Yur answer shuld cnsider: i accidental lss f data ii hardware prblems iii deliberate acts t create prblems by staff r ther peple [16]

10 6. Select TWO f the fllwing methds f data capture: a) MICR b) OCR c) OMR d) Barcde reading Fr EACH: i state a typical applicatin which uses that methd ii describe the frmat f the data befre input iii describe hw the apprpriate input device wrks frm the cmputer pint f view iv explain why it is the MOST apprpriate methd fr that particular applicatin [10 each] 7. a) List FIVE causes f cmputer hardware failure. Fr EACH, state a precautin that culd be taken t minimise r eliminate that prblem. [10] b) List FIVE pssible causes f data lss ther than thrugh hardware failure. Fr EACH, state a precautin that culd be taken t minimise r eliminate the prblem. [10] 8. Read the whle questin befre starting this ne. Select a particular cmpany r rganisatin that yu have studied. a) State the name f the cmpany and its main functins. [2] b) Describe ALL the uses f cmputing in this cmpany. Indicate the type f prcessing in EACH case. [5] c) Describe the specific utputs that cmputers prduce in the cmpany and explain wh uses these and hw they are used. [5] d) List the hardware used in the main applicatins f the cmpany including the number and types f cmputers used. [5] e) Describe the input data needed t prduce the results. [3]