1 Pertemuan 22 Analisis Studi Kasus 2 Matakuliah: H0204/ Rekayasa Sistem Komputer Tahun: 2005 Versi: v0 / Revisi 1

2 Learning Outcomes Pada akhir pertemuan ini, diharapkan mahasiswa akan mampu : Menghubungkan antara repair system dengan discard system

3 Outline Materi Repair versus Discard EvaluationStudi kasus : Repair versus Discard Evaluation

4 Studi Kasus 2 : Repair versus Discard Evaluation Bacalah studi kasus berikut ini In expanding the maintenance concept to establish criteria for equipment design, it is necessary to determine whether it is economically feasible to repair certain assemblies or to discard them when failures occur. If the decision is to accomplish repair, it is appropriate to determine the maintenance level at which the repair should be accomplished (i.e. intermediate maintenance or supplier/ depot maintenance). Suppose that a computer system will be distributed in quantities of 65 throughout three major geographical areas. The system will be utilized to support both scientific and management functions within various industrial firms and government agencies. Although the actual system utilization will vary from one consumer organization to the next, an average utilization of 4 hours per day (for a 360-day year) is assumed.

5 Studi Kasus 2 : Repair versus Discard Evaluation The computer system is currently in the early development stage, should be in production in 18 months, and will be operational in 2 years. The full complement of 65 computer systems is expected to be in use in 4 years and will be available through the eight year of the program before system phase out commences. The system life cycle, for the purposes of the analysis, is 10 years. Based on early design data, the computer system will be packaged in major units with a built-in test capability that will isolate faults to the unit level. Faulty unit will be removed and replaced at the organizational level (i.e comsumer’s facility), and sent to the intermediate maintenance shop for repair. Unit repair will be accomplished through assembly replacement, and assemblies will be either repaired or discarded. There is a total of 15 assemblies being considered, and the requirement is to justify the assembly repair or discard decision on the basis of life-cycle-cost criteria.

6 Studi Kasus 2 : Repair versus Discard Evaluation The stated problem primarily pertains to the analysis of 15 major assemblies of the given computer system configuration to determine whether the assemblies should be repaired or discarded when failures occur. In other words, the various assemblies will be individually evaluated in terms of (1) assembly repair at the intermediate level of maintenance, (2) assembly repair at the supplier or depot level of maintenance, and (3) disposing of the assembly. Life-cycle costs, as applicable to the assembly level, will be developed and employed in the alternative selection process. Total overall computer system costs have been determined at a higher level, and are not included in this example. The objective is to be consistent in analysis approach and in the use of input cost factors to the maximum extent possible and where appropriate.

7 Studi Kasus 2 : Repair versus Discard Evaluation The summary results for all 15 assemblies are presented in table 22.1 Assembly Number Maintenance StatusDecision Repair at Intermediate Cost ($) Repair at Supplier Cost ($) Discard at failure Cost ($) A - 1 A - 2 A - 3 A - 4 A - 5 A - 6 A - 7 A - 8 A - 9 A - 10 A - 11 A - 12 A - 13 A - 14 A ,665 58,149 85,115 85,778 66,679 65,101 72,223 89,348 78,762 63,915 67,001 69,212 77,101 59,299 71,919 64,952 51,341 81,544 78,972 61,724 72,988 75,591 78,204 71,444 67,805 66,158 71,575 65,555 62,515 65, , ,611 73,932 65,071 95,108 89,216 92,114 76,222 89,875 97,212 64,229 82,109 83,219 62,005 63,050 Repair – intermediate Repair – Supplier Discard Repair – Supplier Repair – intermediate Discard Repair – Supplier Repair – intermediate Discard Repair – intermediate Repair – Supplier Repair – intermediate Discard Policy Cost1,071,2671,035,6121,343,449

8 TUGAS / Diskusi Dari data yang diberikan, Buatlah model operational requirement, maintenance concept, and program plan Berikan rekomendasi untuk setiap item (dari A-1 sampai A-15) dalam mempertimbangkan maintenance cost Menurut anda, pilihan mana yang terbaik dari ketiga alternatif biaya perbaikan (maintenance cost), dan mengapa pilihan tersebut yang anda pilih. Diskusikan dalam kelompok dan kemudian dipresentasikan pada pertemuan berikutnya