UNIVERSITEIT VAN PRETORIA / UNIVERSITY OF PRETORIA

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1 UNIVERSITEIT VAN PRETORIA / UNIVERSITY OF PRETORIA FAKULTEIT IBIT FACULTY OF EBIT DEPARTEMENT INFORMATIKA / DEPARTMENT OF INFORMATICS INFORMATIKA 253 / INFORMATICS 253 EKSAMEN 3 Junie 2002 / EXAM 3 June 2002 Tyd: 3 ure Time: 3 hours Punte: 100 Marks: 100 Dosente / Lecturers: Mev/Mrs. E Venter Mnr/Mr. JG le Roux Mev/Mrs. PM Alexander Me/Ms. MA Masoeu Moderator / Moderator: Mnr/Mr. P Joubert BELANGRIKE INLIGTING 1. Slegs eksamen- en hereksamenuitslae van eerstejaar studente sal so gou as wat dit beskikbaar is deur die fakulteitsadministrasie op die kennisgewingborde langs die Geesteswetenskappegebou aangebring word. Tweede- en derdejaar-, asook nagraadse studente kry uitslae op die MTN-lyn asook op die Intranet. Uitslae word so spoedig moontlik na die eksamenperiode aan kandidate gepos. Uitslae sal telefonies by telefoonnommer beskikbaar gestel word, asook op Intranet: adres student online. GEEN UITSLAE SAL TELEFONIES OF PERSOONLIK DEUR DOSENTE OF ADMINISTRATIEWE PERSONEEL VERSTREK WORD NIE. 2. Hereksamens word nie outomaties toegeken nie. Elke uitslag word individueel beoordeel om te bepaal of 'n hereksamen toegeken behoort te word, al dan nie. 3. Hereksamens vind vanaf 25 Junie tot 02 Julie 2002 plaas en studente moet die kennisgewingborde voor die Hoofingang van die Merensky-biblioteek raadpleeg om vas te stel op welke datum, eksamensessie en plek hereksamens afgelê moet word. Roosters is op die Intranet verkrygbaar: student online. 1 van/of 8

2 IMPORTANT INFORMATION 1. The results for examinations and supplementary examinations for first year students only will be displayed on the notice boards next to the Human Sciences Building. The results for second and third year, as well as postgraduate students will only be available on the MTN line and Intranet at student online. Results will be mailed to individual candidates after the examination period. Results will be available at telephone no as well as on the Intranet address: student online. LECTURERS AND ADMINISTRATIVE STAFF WILL NOT GIVE CANDIDATES THEIR RESULTS PERSONALLY OR BY TELEPHONE. 2. Supplementary examinations are not granted automatically, but the results obtained are considered individually to determine whether a supplementary examination should be granted. 3. Supplementary examinations take place from 25 June to 02 July Students should consult the notice-boards at the main entrance to the Merensky Library to determine the date, time and place of their supplementary examinations. Timetables will also be available on the Intranet: student online. AFDELING A / SECTION A (TOEBOEK, CLOSED BOOK) [40 Punte/Marks] VRAAG 1 \ QUESTION 1 [4 Punte / Marks] Logiese stelsel modelle word gebruik om die besigheidsbehoeftes voor te stel en fisiese stelsel modelle om die tegniese ontwerp voor te stel. Verduidelik waarom stelsel analise aktiwiteite op die logiese stelsel modelle fokus. / Logical system models are used to depict business requirements and physical system models to depict technical designs. Explain the reasons why systems analysis activities tend to focus on the logical system models. (4) VRAAG 2 \ QUESTION 2 [10 Punte / Marks] 1. Definieer normalisasie en verduidelik die drie formate met verwysing na die volgende TakRekening tabel. / Define normalization and explain the three formats, referring to the following table of BranchAccount. (4) 2. Verander die meegaande tabel om die entiteite in 3NF voor te stel. / Redraw the table to transform the entities into 3NF: (6) tblbranchaccount Acc# custname custcity loantype branchcode branchname PManager PManagerName 1234, 5679 Hall,A Pretoria Current, Home 124 Hatfield 100, 102 Nel, Venter 9999 Allenl,D Pretoria Savings 124 Hatfield 100 Nel 2345 Black,B Pretoria Savings 147 Brooklyn 101 Botha 3456 Smith,C Benoni Home 247 Bendor 200 Steyn VRAAG 3 \ QUESTION 3 [4 Punte / Marks] 1. Vergelyk datavloeie en datastore in tabelformaat / Compare data flows and data stores in table format (2) 2. Vergelyk data-entiteite en eksterne entiteite ( genoem eksterne agente) in tabelformaat / Compare data entities and external entities (also called external agents) in table format (2) 2 van/of 8

3 VRAAG 4 \ QUESTION 4 1. Verduidelik die term veralgemening. / Explain the term generalization (1). 2. Deur gebruik te maak van die volgende objekte, teken n diagram om die konsep objeksupertipe(s) en subtipe(s) te illustreer. / Using the following objects, draw a figure to illustrate the concept object super type(s) and object subtype(s). (4) Dokter / Doctor Pasient / Patient Hospitaal-bestuurder / Hospital Manager VRAAG 5 \ QUESTION 5 Vergelyk die ooreenkomste en verskille tussen n konteksdiagram en n Use Case - diagram in tabelformaat. / Compare the similarities and differences between a Context Model diagram and a Use Case Model diagram in table format. (5) VRAAG 6 \ QUESTION 6 Uitvoerbaarheids-analise is n belangrike fase in die stelselontwikkelingslewensiklus (SOLS). Stem u saam met die stelling of nie? Motiveer u antwoord. / Feasibility analysis is an important phase in the systems development life cycle (SDLC). Do you agree or disagree with the statement? Motivate your answer. (5) VRAAG 7\ QUESTION 7 [2 Punte / Marks] Watter kriteria word gebruik om die operasionele uitvoerbaarheid van n projek te evalueer? / What criteria can be used to evaluate the operational feasibility of a project? (2) VRAAG 8 \ QUESTION 8 Voordele van n projek verhoog normaalweg die wins van n projek of verlaag die kostes. Wat is die verskil tussen n tasbare- en n ontasbare voordeel? Gee twee voorbeelde van elk. / Benefits of a project normally increase profits or decrease costs. What is the difference between a tangible and an intangible benefit? Give two examples o f each. (5) AFDELING B / SECTION B (OOPBOEK, OPEN BOOK) [30 Punte/Marks] VRAAG 1 \ QUESTION 1 [24 Punte / Marks] Konstrueer die volgende diagramme vir die Tool Crib stelsel (Aanhangsel A) / Construct the following diagrams for the Tool Crib system (Appendix A): 1. Konteks diagram / Context diagram (8) 2. Objekklas-diagram: objekte met attribute en gedrag/metodes, verwantskappe tussen objekte en kardinaliteite duidelik aangedui / Object class diagram: objects with attributes and behavior/methods, relationships between objects and cardinalities clearly indicated (16) 3 van/of 8

4 VRAAG 2 \ QUESTION 2 [6 Punte / Marks] n Nuwe produksie-skedulering-inligtingstelsel vir XYZ Korporasie kan ontwikkel word teen n koste van R Die verwagte netto bedryfskostes en die verwagte netto voordele oor vyf jaar vir die projek is as volg: / A new production scheduling information systems for XYZ Corporation could be developed at a cost of R The estimated net operating costs and estimated net benefits over five years of operation would be: Jaar/Year Beraamde netto bedryfskoste /Estimated Net Operating Costs (in Rand) Beraamde netto voordele /Estimated Net Benefits (in Rand) Teen n verdiskonteringskoers van 12 persent, wat behoort die (geskatte) terugbetalingsperiode vir hierdie belegging te wees? Sal u dit as n goeie of swak belegging beskou? Motiveer u antwoord. / Assuming a 12 percent discount rate, what would be the (estimated) payback period for this investment? Would this be a good or bad investment? Motivate your answer. (1) 2. Bereken die netto teenswoordige waarde van die belegging as n verdiskonteringskoers van 12 persent gebruik word. / Calculate the net present value of the investmen t if the current discoun t rate is 12 percent. (5) AFDELING C / SECTION C (DELPHI OOP BOEK/OPEN BOOK) [30 Punte/Marks] VRAAG 1 \ QUESTION 1 Teken n vloeikaart vir die speletjie hoog-laag in Aanhangsel B / Develop a flowchart for the game of high-low in Appendix B. [5] VRAAG 2 \ QUESTION 2 [10 Punte / Marks] Skryf n enkele prosedure vir die Delphi-program vir die hoog-laag speletjie volgens die beplanning in Vraag 1. Die parameters vir die prosedure is as volg: die mees onlangse raaiskoot van die tweede speler, die nommer gekies deur speler een en die hoeveelheid probeerslae tot dusver. Die prosedure moet die boodskap te laag, te hoog of korrek vir elke raaiskoot vertoon. / Write a single procedure for a Delphi program for the highlow game as planned in Question 1. The parameters for the procedure are: the most recent guess by the second player, the number selected by the first player and the number of tries so far. The procedure must display the message lower, higher or correct for each try. [10] VRAAG 3 \ QUESTION 3 Bereken die waarde van myvalue tydens die uitvoer van die kode in Program 1 in Aanhangsel B. / Handexecute the code for Program 1 in Appendix B and give the value of myvalue. [5] 4 van/of 8

5 VRAAG 4 \ QUESTION 4 [10 Punte / Marks] Identifiseer al die foute in Program 2 in Aanhangsel B. Spesifiseer ook die tipe fout gemaak in elke geval en beskryf wat u sou doen om die fout te korrigeer. / Identify all the errors in Program 2 in Appendix B. Specify what type of error has been made and also describe how you would fix the problem. Verskaf u antwoord in die volgende format: / Provide your answer in the following format: Fout in kode/error in code Tipe fout/type of Error Oplossing/How to fix the problem [10] 5 van/of 8

6 Aanhangsel A / Appendix A Die Tool Crib stelsel Die funksie van die Tool Crib is om gereedskap en materiale aan die werknemers van Physical Plant te verskaf om hulle werk te kan doen. Werknemers ontvang elkeen n gereedskapkis met die algemene, redelik goedkoop gereedskapstukke in, naamlik hamers, skroewedraaiers, maatbande en so meer. Ander gereedskap nodig om hulle werk te doen, moet deur die Tool Crib uitgeteken word. As die werk voltooi is moet die werknemer die uitgetekende gereedskapstuk terugbring. Gereedskap kan egter verlore raak, gesteel of beskadig word en word dus nooit teruggeteken en beskikbaargestel vir ander nie. Die Tool Crib hou rekord van die uit- en terugteken van gereedskap, monitor werknemers en hulle aanspreeklikheid ten opsigte van die gereedskap en hanteer n voorraadhoudingsubstelsel vir die voorraadstoor. Die voorraadstoor is ook verantwoordelik vir die verkryging en stoor van materiaal nodig om verskillende take te verrig. So word die voorraadvlakke van skroewe, spykers, saamgeperste-hout, gipsbord en ander materiale gehandhaaf. Materiale word vanaf verskeie verskaffers bestel. As werknemers enige materiale benodig om n taak te voltooi, moet hulle met die voorraadstoor kontroleer of dit beskikbaar is. Indien dit nie beskikbaar is nie kan hulle intussen n ander taak voltooi. Die voorraadstoor sal dan die nodige materiale bestel en dit aan die werknemer verskaf. Die werknemer moet n werknemers ID toon wat eers bevestig word deur die werknemer-moniteringstelsel voordat die werknemer gemagtig word om gereedskap uit te teken. Sodra die werknemer gemagtig is, sal n personeellid by die Tool Crib die volgende doen vir elke verlangde gereedskapstuk: met die nodige beskrywing van die gereedskapstuk sowel as die hoeveelheid benodig, word die hoeveelheid in voorraad sowel as die beskikbaarheidstatus bepaal. As die gereedskapstuk beskikbaar is vir uitteken, word die gereedskapbeperkinge nagegaan om te verseker dat die werknemer die nodige vaardigheidskwalifikasie het om die gereedskap te kan gebruik. As die werknemer gemagtig is, die gereedskap is beskikbaar en die werknemer is gekwalifiseer om die stuk te gebruik, word die gereedskapstuk uitgeteken en die transaksie gedokumenteer. Die werknemer ontvang n kwitansie met details van die transaksie. Die gereedskapvoorraad word dan opgedateer. Alle transaksies word in n transaksie-lêer gedokumenteer. Met die terugbring van n gereedskapstuk moet die werknemer die kwitansie saam met die gereedskapstuk aan die personeellid van Tool Crib teruggee. Die terugbring-transaksie word gedokumenteer en die gereedskapvoorraad word opgedateer. n Weeklikse verslag met uitstaande gereedskap word na die bestuur van Physical Plant gestuur. Die werknemer word nie toegelaat om enige verdere gereedskap uit te teken nie voordat die uitstaande stuk of teruggegee is of n aanvaarbare verklaring verskaf is hoekom dit steeds uitstaande is. The Tool Crib system The Tool Crib s function is to provide the tools and materials needed by Physical Plant employees to perform their job duties. Employees are provided with a toolbox containing commonly used, and relatively inexpensive tools such as hammers, screwdrivers, tape measures, and so on. Other tools that are needed to complete a job must be checked out through the Tool Crib. When the job is completed, the employee must return the checked-out tool. Oftentimes tools become lost, stolen, or damaged and are theref ore never checked back in and made available for others. The Tool Crib system tracks the check-in and check out of tools, monitor employees and their tool accountability and manages an inventory subsystem for the warehouse. The Warehouse is also responsible for obtaining and storing supplies that are needed to complete jobs. For example, the Warehouse makes sure to maintain a supply of screws, nails, plywood, drywall, and other materials. Materials are ordered from various suppliers. When workers need materials for a job assignmen t they are supposed to check at the warehouse to see if the goods are available. If the goods are not available, they simply move on to the next job assignmen t. The warehouse will then order the required materials and provide for the delivery of materials to employees. 6 van/of 8

7 The employee will supply an employee ID, which is first confirmed through the employee monitoring subsystem before the employee is authorized to check out tools. If the employee is authorized, a staff member at Tool s crib does the following for each requested tool: Given the description of the needed tool and the requested quantity, locates the tool by checking on its quantity on hand or availability status. If the tool is available for check out, checks the tool restrictions to confirm that the employee has been assigned an acceptable skill classification for using that tool. If the employee is authorized, the tool is available, and the tool is no t restricted from use by that employee, record the tool check-out. The employee is supplied with a receipt that details the check-out. The tool inventory is then updated. All transactions are recorded in a tool transaction tool file. On return of a used tool the employee presents his/her receipt and gives the tool back to the staff member of the Tool Crib. The check-in transaction is recorded and the tool inventory is updated. A weekly report of unreturned tools is sent to the management of Physical plant. The employee is not allowed to check-out any more tools before the outstanding one is either returned or an acceptable explanation of why it could not be returned is provided. 7 van/of 8

8 Aanhangsel B / Appendix B Reëls vir die Hoog-Laag speletjie / Rules of the High-Low game: Die eerste speler voer n nommer tussen 0 en 100 in. Die tweede speler probeer die keuse raai. As die raainommer laer is as die gekose nommer, reageer die rekenaar met te laag. As die raainommer meer is as die gekose nommer, verskyn die boodskap te hoog. Die speletjie eindig as die tweede speler die korrekte nommer raai. Die program moet rekord hou van die aantal raaiskote en die inligting moet aan die einde van die speletjie vertoon word. / The first player enters a number between 0 and 100. The second player then tries to guess the first player s number. If the number is lower than the guess, the computer responds lower. If the number is higher than the guess, the computer responds higher. The game ends when the second player correctly guesses the first player s number. The program should track the number of guesses and display this information when the game ends. Program 1 procedure TForm1.btnCalculate2Click(Sender: TObject); var myvalue : Integer; X : Integer; Y : Integer; Z : Integer; begin X := 5; Y := 3; myvalue := 0; Repeat X := (X + Y) div 2 + 3; Z := sqr(x mod 3); myvalue := myvalue + Z; Until myvalue > 25; ShowMessage(IntToStr(myValue)); end; Program 2 procedure TForm1.Button1Click(Sender: TObject); var myinfile : Textfile; myline : String; X : Integer; MyData : array[1..15] of String; begin X := 1; AssignFile(myInFile, C:\June3.txt ); Rewrite(myInFile); While X <= 15 do begin mycounter := mycounter + 1; Readln(myInFile, myline); mydata[x] := myline; end; CloseFile(myInFile); lblimport.caption := mycounter + ' records imported ; end; 8 van/of 8