טכניון מכון טכנולוגי לישראל
הטכניון מכון טכנולוגי לישראל - בית הספר ללימודי מוסמכים  
M.Sc Thesis
M.Sc StudentFuchs Tiziana
SubjectStudy of Complex Model with an Emphasis on the Link
between the Field Performance and Logistic Chains
DepartmentDepartment of Quality Assurance and Reliability
Supervisor Dr. Anatoly Goldfeld
Full Thesis text - in Hebrew Full thesis text - Hebrew Version


Abstract

Management requires of engineers a performance assessment relating to any system, and to the entire deployment, immediately at the onset of project planning through to decommissioning. A further requirement is an assessment of the robustness vis-à-vis various loads, and environmental logistical conditions that pertain to the mission. Furthermore, the availability and robustness (quality of service) assessments must relate to available budgets, in order to allow the plans to stay up-to-date and competitive. For the lifetime of the system, one is called upon to examine and make recommendations about the characteristics of the “optimal system”: will the solution focus on logistics and resources, on improving low-reliability components, or on increasing system redundancy?

The purpose of the paper is to evaluate the applicability of simulation software to the calculation of availability levels of complex  systems with a multi-echelon structure.

The evaluation is based on models that include: the structure of the reliability of the system, a hierarchical tree of the organization, the number of logistical levels and the geographic location of warehouses, the impact of the quantity of spare parts and the number of repair teams and their composition in the various workshops, quality of repair (with or without renewal), preventative maintenance (depth and frequency of maintenance), and the impact of the cost of the overall solution Vs the level of availability achieved.

The research was carried out by defining a project typical of complex systems, examining parameters (such as quantity of spare parts, staffing levels and qualifications, preventative maintenance, transport and quality of repair) and measuring these parameters' impact on the system's performance. The analysis was done using the “Annabelle” simulation software package.

We found that by connecting the simulation to an economic formula, it is possible to find the preferred alternative from both the economic and performance aspects.

"Annabelle" enables the analysis of any organizational re-structuring (workshop levels, locations, warehouses, resources, transportation, combined resource utilization, etc.), yielding its impact on the field performance. These analyses allow examination of the system's behavior under various scenarios, and allow prediction of the performance of the logistical array and the systems' availability as a consequence of any changes. Thus, we can assess the adaptability of the logistical array to such changes, and integrate changes in the supportive structures so that the performance level will remain acceptable or will adapt to an increased load in situations such as an emergency.