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The Effect of Requirement Creep on the Fixed-Cost Project Planning

요구사항 변경이 확정가 프로젝트 계획에 미치는 영향

  • 이상운 (강릉대학교 컴퓨터공학부)
  • Published : 2007.10.31

Abstract

To develop a dynamic system project in which the requirement changes frequently, it's impossible to finish the development within a fixed-cost due to additional budget occurring in need of requirement creep. To manage the successive project within a fixed-cost, it's better to manage the ratio of necessarily changed size of project and necessary optional requirement. According to Bhagwat, it is occurred in the construction phase. Also, he stated that the software development cost, construction phase cost and requirement cost are equal and it was wrong explanation in the ratio of requirement creep and optional requirement. This paper assumes the requirement creep to be happening in the phase of elaboration and construction. In addition, some differences were supposed to happen between software development cost, construction phase cost, and requirement creep cost. As a result, the reality was preferred rather than the ratio of optional requirement and the ratio of requirement creep.

요구사항이 빈번히 변경되는 동적 비즈니스 시스템 프로젝트를 확정가로 개발할 경우, 개발과정에서 발생하는 요구사항의 변경에 따른 추가 소요 비용으로 인해 확정가 범위 이내로 개발을 완료하는 것은 거의 불가능하다. 확정가 범위 이내에서 성공적으로 프로젝트를 완료하기 위해서는 요구사항 변경 규모와 이에 기반하여 개발이 되지 않아도 되는 옵션 요구사항의 비율을 관리하여야 한다. 이에 대해 Bhagwat는 요구사항 변경이 구축단계에서만 발생한다고 한정하였다. 또한, 소프트웨어 개발비용, 구축단계 소요 비용과 요구사항 변경에 소요되는 추가 비용이 동일하다고 가정함으로써 요구사항 변경 비율과 옵션 요구사항의 비율 유도의 모순을 보였다. 본 논문은 요구사항 변경은 정련단계와 구축단계에서 발생한다고 가정하였다. 또한, 소프트웨어 개발비용, 구축단계 소요 비용과 요구사항 변경 비용간에는 차이가 발생한다고 가정하였다. 그 결과 확정가 대비 요구사항 변경에 따른 추가 소요 비용과 개발이 되지 않아도 되는 옵션 요구사항의 비율도 보다 현실성을 반영하는 결과를 얻을 수 있었다.

Keywords

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