As Computing Mark Scheme

UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS GCE in advance(p) underling Level and GCE Advanced Level go afterwardsing SCHEME for the May/June 2009 head make-up for the guidance of teachers 9691 COMPUTING 9691/01 paper 1 (Written Paper 1), scoopimum raw mark 90 This mark scheme is print as an aid to teachers and jakesdidates, to foretell the requirements of the examination. It shows the primer coat on which Examiners were instructed to award marks.It does not indicate the details of the discussions that took place at an Examiners shock before marking began, which would have considered the acceptableness of alternative answers. foretoken schemes must be read in conjunction with the question c over and the report on the examination. CIE volition not enter into discussions or commensu trampness in connection with these mark schemes. CIE is make the mark schemes for the May/June 2009 question papers for most IGCSE, GCE Advanced Level and Advanced Subsidiary Leve l syllab make use ofs and some fair Level syllabuses.P date 2 1 (a) Mark avoidance Teachers version GCE A/AS aim May/June 2009 ready reck peerless(a) and only(a)r programme 9691 Paper 01 (i) To drop by the elanside the user to saltation the computer info/change breeding into computer understandable abidance (ii) To waive the computer to give information/ guide with the computer/to change information from computer into human understandable form (iii) To apply entropy while the computer is not using it (1 per dotty) 3 (b) -Black and white optical maser -e. g. role in office to produce letter -Produces high superior/speedy so does not develop large stand on a LAN - food coloring laser -e. g. To produce reports for a meeting -High quality outputs/ ordure produce large amount quick -Dot Matrix e. g. Print pass on at checkout/tickets on railway line -Produces more than one simulate at a clip, one for client + one for shop -Inkjet -e. g. Doing dwellingwork at ho me -Relatively cheap and slowness does not motion -Plotter -e. g.Produce architects plans -Precision selective service tool -Braille printer -Producing documents/books for blind good deal -Outputs physical/3D form of data (3 per showcase, slime 3 types, max 9) 2 (a) (i) Name Text/ attract/ of import/alphanumeric Description Text/String/alpha/alphanumeric Cost bills/integer/real/float Whether Boolean Number Integer (1 for first three, 1 for last 2) (ii) Field Sizes 10 50 4 1 1 66 50 250 8 4 313 bytes (1) 9 2 arrive (1) for showing that the field surfaces should be added up Multiply Total by gm (1) = 66000 to 313000 bytes Add extra (10%) for overheads (1) = 72600 to 344300 bytes Convert to logical unit (? 024) (1) = 70. 9Kb to 344. 3Kb. (5 possible mark points, max 4) 4 UCLES 2009 Page 3 Mark Scheme Teachers version GCE A/AS LEVEL May/June 2009 political program 9691 Paper 01 (b) gain -Processed/Searched more easily/quickly/ deem of file size is easier -e. g. When a client wants to know the availability of an item the book dejection be found quickly/makes selection of storage easier Disadvantage -The size of fields must be goaded before use so quad is often wasted/not ample -e. g. The description field may not be large enough for a particular item. 1 per -, max 4) 4 3 -Working from home -Fewer journeys/more free time/less supervision -Different types of melodys/jobs wooly-minded/job opportunities arising -Production line/manual jobs being lost/replaced by more technical jobs -Work through with(p) can be more evident to managers -All work/times working can be seen/leading to rewards where appropriate/sanctions when hapless effort -Safety of workers is improved -Computers/robots do dicey tasks/can be utilize to accurately monitor dangerous processes -Work time can be less rigid -Work can be fitted in round separate loadings/leads to simpler ways of job sharing -The 24 hour job/office/commitment/world workforce -Workers may cease lessly be contactable/throughout the world/communications. (Up to 2 per group, max 3 groups, max 6) 6 (a) stage business X A OUTPUT figure 1 1 3 1 1 4 1 1 1,1 5 2 1 6 2 1 TRUE 3 2 4 4 2 4 2,4 5 3 4 6 3 4 ill-advised 7 3 4 (1 for determine of X and matching line song 1 for values of A like to values of X 1 for plentiful correct outputs 1 for giving 2 conditions) 4 (b) (i) Change X = 3 to X = 11 (ii) -A first line to allow user to foreplay value (N) -UNTIL X = (N + 1) 1 2 4 UCLES 2009 Page 4 (c) e. g. Mark Scheme Teachers version GCE A/AS LEVEL May/June 2009 course of instruction 9691 Paper 01X=5 REPEAT A=X*X OUTPUT X, A X=X+5 UNTIL X = 25 END Mark points -Begins with 5 (as first output) -Loop with working condition -Counter correctly incremented 5 (a) (i) -Options appear on cover out from which to select -Selection may lead to submenus -Menus ordered in a tree grammatical construction (from single root to many branches) economic consumption In a passive information b ody e. g. Tourist guide at a train station. (1 for use, + 2 early(a) -, max 3) 3 3 (ii) -Follows a spoken wording allowing user to input queries in natural vocabulary/syntax -Computer understands keywords/positions in judgment of conviction to get idea of syntax -Will then(prenominal) search data nursing home for keyword to provide output or responses. Use e. g. On an expert system or search engine. 1 for use, + 2 an opposite(prenominal) -, max 3) 3 (b) -Provides utility programs to allow user to carry out keep tasks (any 3) -Provides security quantitys like passwords and identifications. -Controls the strongw ar and the operations they allow. -Provides translators to convert software system into a form useable by the computer. -Manages interrupts. -To provide a platform for the execution of software (1 per -, max 3) 6 (a) (i) data is transmittable on a single wire/one cow dung at a time. (ii) entropy is transmitted along a physique of wires/one byte (or more) at a time. (iii) info can only be transmitted in a single direction. (iv) Data can be transmitted in both directions but only one at a time. (b) (i) -Each byte contains an even up result of 1s -A special sting is set to 0 or 1 to ensure that total is even. Byte is chequered for even number of 1s after transmission. (1 per -, max 2) (ii) -When two bits are in demerit the errors cancel each former(a) out/10101001. 3 1 1 1 1 2 1 UCLES 2009 Page 5 7 Mark Scheme Teachers version GCE A/AS LEVEL May/June 2009 Syllabus 9691 Paper 01 -Data hoard on situate/by drilling /observation/explosions -Data collected remotely/by satellite/by electronic means -Collected data input to system via HCI/automatically -Data input is compared to depository library of data to find matches -by inference engine -Using rules found in rule base -Decisions made about geologic structure reported through HCI. (1 per -, max 4) 4 8 a) -Site map -a draw showing the way the antithetic screens fit unneurotic -sho ws the associate among screens, -Gantt graph/progress chart -shows the different separate that need to be developed -shows which parts of the development are independent and which are reliant on each other. -Spider diagram -to show fundamental interaction between the different elements of the dissolver -and those parts which are independent of each other. -Flow diagram -to show the order of producing the parts of the solution -or to show the flow through the proposed state of affairs. (Up to 2 groups, up to 2 per group, max 4) 4 (b) -Documentation for owner of target -will be paper establish -will contain instructions for changing/maintaining site -Documentation for viewer/visitor to site -will be on-screen -giving detailed help on searches/use of facilities/communication with site owner 4 9 -Sound -Music to accompany the pictures/speech to explain the pictures. television receiver/animation -Moving pictures to better describe the quarry on the site -Automatic hard copy/savi ng -Automatic downloading of data to printer/hard drive for future reference. -Hyperlinks -Allowing access to different sites/parts of site (Up to 2 groups, up to 2 per group, max 4) 4 10 Colour -Contrast -Corporate schemes -Aggressive/passive/soothing colour schemes -Consistency over site to make site take in cohesive -Use colour to provide idiom -Accessability issues e. g. colour blindness UCLES 2009 Page 6 Mark Scheme Teachers version GCE A/AS LEVEL May/June 2009 Syllabus 9691 Paper 01 Layout -Consistent layout so user gets used to what is where. Important things to top and left -Data ranch out across whole screen -Tab order -Group similar data together Content -Limit to amount of content on a page -Content on a page is cohesive -Content matches the published intentions of the site -Content is of commonsensible type and reading age for audience. (1 per -, max 2 per group, max 6) 6 11 -The bit rate is a measure of the rate that data can be sent across the communication spec iality -Different communication media have different bit rates -For simple text/ sedate picturesa low bit rate connection is adequate -because intensity level of data per page is low and fixed -For (live) icon/soundbit rate of necessity to be high -because large volume of data which must be downloaded in real time because -information is time sensitive. 1 per -, max 4) 4 12 (a) (i) -Custom written software is especially written/according to the requirements of the customer -Off the shelf is readily available/ needs tailoring to the needs of the customer 2 (ii) -no retard as it is ready immediately -No shortage of experienced users/ready trained/No learning curve -Software should be error free -Help available through mesh/colleagues/courses -Compatible with other users/software (1 per -, max 2) (b) (i) -Check data input to ensure it matches source data -Typed in twice -by different quite a little/at different times -inputs checked against each other for errors -manual check by comparing -screen output of input with reliable document. (1 for first -, + any 2 other -, max 3) (ii) -Check data input is sensible/follows set rules/are reasonable -Data type/should be numeric -Data format/should be in currency form/xxx. xx -Length check/input should be x characters -Presence check/something has been input. -Range check/value between 0 and some upper determine (1 for first -, + any 2 other -, max 3) 2 3 3 UCLES 2009