ISBN : 978-81-963532-2-3 (E-Book) Thevarious termsof thisexpressionareas follows: Kisthetotaleffortexpended(inPM)intheproductdevelopmentandListheproductsizein KLOC. t correspondstothetimeofsystemandintegrationtesting.Therefore,t approximatelyconsideredas thetime requiredtodevelop thesoftware. k d Cisthestateoftechnologyconstantandreflectsconstraintsthatimpedetheprogressof theprogrammer.TypicalvaluesofC=2forpoordevelopmentenvironment(no k methodology,poordocumentation,andreview,etc.),C k developmentenvironment(softwareengineeringprinciplesare adheredto), C=11foran k excellentenvironment(inadditiontofollowingsoftwareengineeringprinciples,automatedtool sandtechniquesareused).TheexactvalueofCforaspecificprojectcan k becomputedfrom thehistoricaldataofthe organizationdevelopingit. Putnamsuggestedthatoptimalstaffbuild-uponaprojectshouldfollowtheRayleighcurve.Only a small number of engineers are needed at the beginning of a project to carry out planningand specification tasks. As the project progresses and more detailed work is required, the numberof engineers reaches a peak. After implementation and unit testing, the number of project stafffalls. However, the staff build-up should not be carried out in large installments. The team size shouldeither be increased or decreased slowly whenever required to match the Rayleigh-Norden curve.Experienceshowsthataveryrapidbuildupofprojectstaffanytimeduringtheprojectdevelopment correlateswith schedule slippage. Itshouldbeclearthataconstantlevelofmanpowerthroughouttheprojectdurationwouldleadto wastage of effort and increase the time and effort required to develop the product. If a constantnumber of engineers are used over all the phases of a project, some phases would be overstaffedand the other phases would be understaffed causing inefficient use of manpower, leading toscheduleslippageand increasein cost. Effectofschedulechangeoncost Byanalyzing alargenumberof armyprojects, Putnam derived the followingexpression: L= C 1/3 K t k d 174 Software Engineering Keerthana P, Manasa KN, Ganga D Bengal 4/3 =8forgoodsoftware canbe d
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