A one-of-a-kind product manufacturing system (OKP) is a system that makes non-standard products in make-to-order manufacturing environments. This thesis presents 1) a loading scheduling framework for OKP, 2) Capable-To-Promise (CTP) function to generate convincing due dates for customer order quoting, 3) performance analysis of dispatching rules for dynamic scheduling in OKP.
This study develops a functional business process (FBP) model for OKP to identify the functional requirements, and then proposes a loading scheduling framework that satisfies the functional requirements. The framework consists of CTP simulator, initial plan generator, dispatching rule evaluator, real time scheduler. For order quoting, image based variation method for generating proper process planning and CTP loading simulation method is proposed. Whether customer given due dates can be met or not is judged by backward Gantt chart simulation, and in case of failing to meet the customer given due dates, forward Gantt chart simulation generates expected order delivery dates.
To fulfill the customer order in due time in OKP, extensive performance analysis of dispatching rules for dynamic scheduling is presented. Five dispatching rules: Job due-date (JDD) rule, Normalized JDD rule, latest finish date (LFD) rule, latest start date (LSD) rule, and Refined LSD rule are identified. The performance analysis shows that 1) JDD, LFD and LSD rules perform fairly well, which is compatible with the results of existing studies, 2) Refined LSD rule outperforms other rules, 3) Normalized JDD rule performs very poorly. Also presented is a framework of simulation-based dynamic scheduling in which the Refined LSD as well as the `try-every-rule' approach can be effectively utilized.
단품수주생산 제조시스템(OKP)은 MTO제조 환경에서 비표준화 제품을 만드는 방식이다. 이 논문은 1)OKP를 위한 로딩 스케쥴링 프레임, 2)고객 주문 견적에 대한 납기를 생성하는 CTP 기능, 3)OKP에서의 동적 스케쥴링을 위한 디스페칭 룰에 대한 성능 분석을 다룬다. 본 연구에서는 기능적 요구사항을 확인하기 위해 OKP를 위한 기능적 비즈니스 프로세스 모델을 개발하고, 그 기능적 요구사항을 만족시키는 로딩 스케쥴링 프레임을 제안한다. 프레임은 CTP 시뮬레이터, 초기 투입 계획 generator, 디스페칭 룰 evaluator, 실시간 스케쥴러로 구성된다. OKP에서 주문 납기를 만족시키기 위해 동적 스케쥴링의 디스페칭 룰의 막대한 성능 분석이 필요하다. 다섯가지 디스페칭 룰은 다음과 같다: Job due-date (JDD) rule, Normalized JDD rule, latest finish date (LFD) rule, latest start date (LSD) rule, and Refined LSD rule. 성능 분석 결과 기존 연구의 결과들과 같이 1)JDD, LFD, LSD 룰이 상대적으로 좋고, 2)RefinedLSD 룰이 다른 룰보다 확실히 좋은 성능을 보였고, 3)Normalized JDD 룰의 성능이 제일 좋지 않았다.
