Distributionally Robust Joint Chance Constrained Vessel Fleet Deployment Problem

This work investigates the problem of vessel fleet deployment for liner shipping. The objective is to minimize the total cost, i.e., the sum of vessel chartering cost and vessel-route operating cost. In the considered problem, the shipment demand for each route is uncertain and its distribution is unknown. Due to lacking historical data, we use the moment-based ambiguity set to characterize the unknown distributions of demands. We then introduce a distributionally robust model and propose a new approximation approach to solve this problem. Finally, numerical experiments are conducted to demonstrate the performance of our approximation approach.

IMPLEMENTASI METODE DMAIC (DEFINE, MEASURE,ANALYZE, IMPROVE, CONTROL) UNTUK MENURUNKAN CACAT BONDING SEPATU DI GEDUNG 2 (DUA) PADA PT. PARKLAND WORLD INDONESIA

This study focuses on how to control defective products at PT. Parkland World Indonesia, a company engaged in the Adidas brand shoe industry for the period April 2020 to March 2021, the average product achievement reaches 8.37%, while the company wants Zero Defect. The purpose of this study is to reduce bond defects through an approximation approach, where we observe and conduct tests in order to improve performance and reduce. The method to guarantee the quality of the product produced is DMAIC (Define, Measure, Analyze, Improve, Control) which is a data-based problem solving approach that helps to optimally correct defects caused by the production process can decrease. The results of the analyzed data showed 5 CTQ (Critical to Quality) bonds with the highest percentage of bonding stabilizer at 43.70%. The conclusions and recommendations that can be drawn from this study are the causes of shoe ties that can be prevented by implementing several proposed improvements, by providing the latest SOPs, maximum WIP visual standards, brush change visual systems, and providing RCA (root cause analysis) board meetings

A Two-Point Approximation Approach to Determining Aircraft Aerodynamic Force Coefficients for a Maximal-Duration Horizontal Flight

This paper proposes a two-point approximation approach to determining aircraft aerodynamic force coefficients, and compares it to the traditional methods. A variational concept is used to conduct aircraft flight trials for the maximal duration of quasi-horizontal flights. The advantages of the described optimization theories are demonstrated, in terms of aviation fuel gas savings. The results of a numerical example are presented.