Douglas L. McWilliams

Genetic-based scheduling to solve the parcel hub scheduling problem

The parcel hub scheduling problem (PHSP) is scheduling problem that is common in the parcel delivery industry. The PHSP consists of scheduling a set of inbound trailers containing a batch of heterogeneous parcels to a set of unload docks with the objective of minimizing the time span of the transfer operation. The transfer operation involves unloading the inbound trailers and sorting and loading the parcels onto outbound trailers. The unload schedule can have a significant impact on the amount of time required to complete the transfer operation. In this paper, a mathematical model is proposed to solve small-size problems and a genetic algorithm is presented to solve the large-size problems with minimum computational time compared to other competing approaches.

Iterative improvement to solve the parcel hub scheduling problem

This paper presents iterative improvement algorithms to solve the parcel hub scheduling problem (PHSP). The PHSP is combinatorial optimization problem that consists of scheduling a set of inbound trailers to a small number of unload docks. At the unload docks, the inbound trailers must be unloaded and the parcel sorted and loaded onto outbound trailers. Because the transfer operation is labor intensive, the transfer of parcels must be done in such a way as to minimize the timespan of the transfer operation. Local search (LS) and simulated annealing (SA) algorithms are developed and evaluated to solve the problem. The performances of the algorithms are compared to the performance of an existing genetic algorithm (GA). The computational results show that the LS and SA algorithms offer solutions that are superior to those offered by the GA.

Enhancing Lean Manufacturing Learning Experience Through Hands-On Simulation

Finding appropriate interactive exercises to increase students’ learning in technical topic courses is always challenging to educators. In this study, several paper plane hands-on simulation exercises were developed, used, and tested in a lean manufacturing course for beginning college students. A pretest and posttest was used to assess the effectiveness of students learning of lean manufacturing concepts by means of participating in the hands-on simulation exercises. Furthermore, the procedures used for an efficient integration of the hands-on simulation exercises into a teaching environment were evaluated. The results showed that students’ knowledge of lean manufacturing concepts increased significantly compared with lecture-based learning only.

Simulation Design for Off-Line Training of Practical Lean Manufacturing Concepts for Visual Inspection

Customer needs for high-quality goods and the risk of product-liability litigation against businesses have made companies look for a way to sustain quality assurance in their products and services. Lean manufacturing is the latest and most successful system being used by companies to turn their business around. Visual inspection plays an important role to ensure quality product in manufacturing and service industries. Simulation accompanied by training has been proven to be effective in implementing lean concepts in visual inspection systems by enhancing operator accuracy and reducing search time. This article describes the development and application of a training system in a simulated visual inspection environment using a computer-based program to mimic the actual industrial setting. The system is designed and used to simulate and evaluate lean metrics such as time, accuracy, pacing, and data collection needed to train visual inspectors off-line.

Exploring mathematical approximation for the time spans of transfer operations in parcel transshipment terminals

The parcel delivery industry (PDI) is a very labor intensive industry, from the drivers of the pickup and delivery vans, to the unloaders, sorters, and loaders in the transshipment terminals. The labor efficiency is a key performance measure in the PDI. In this study, the focus is on developing a framework for improving labor efficiencies in a parcel transshipment terminal. The objective is to minimize the time required to transfer parcels from inbound trailers to outbound trailers. This paper is an exploratory study to developing a framework for a solution approach to solve large-scale parcel hub scheduling problems (PHSP). A binary integer programming (BIP) model is proposed along with a branch and bound (BaB) algorithm with lower and upper bounds. The computational study shows that the BaB algorithm is able to generate solutions for small-size problems. The proposed BIP model sets the ground work for developing solution approaches to much larger size problems.

Exploring the Application of Simulations and Games in Advanced Manufacturing

Simulations and games are typically used in education, training, and research. Simulation & Gaming has published articles on simulation and gaming for a variety of contexts. We are pleased to present, for the first time, this issue on Exploring the Application of Simulations and Games in Advanced Manufacturing, with a special emphasis on Lean. Our objective is to broaden the coverage of simulation and gaming by initiating the publication of lean manufacturing–related simulation articles. The first article, “Simulations and Games for Teaching Lean Manufacturing: A Survey and Future Directions,” sets the stage for this special issue. The article presents a critical assessment of existing simulations for lean manufacturing instruction. A taxonomy was developed to summarize the current state of these resources based on the principles/practices emphasized, the focus in terms of the activity simulated, the lean tools and techniques covered, and the use of assessments to evaluate the simulations. Four gaps are found in existing simulation designs: lack of stress on soft skills, a mistaken focus on “linear lean,” misunderstanding of the key role of the facilitator, and lack of realism. They followed up by identifying gaps and proposing best practices for developing simulations for Lean Manufacturing education and training. The second article examines the application of games to learning of lean concepts by office and administrative personnel. This article presents a web-based version of a lean simulation training game. As with any educational game, in order to be effective, it is important that such a game be not only educational but also fun, realistic, and easy to play. In addition to these general game characteristics, for a lean game to be truly effective, it is important that the game is also intuitive and inspirational. The article, “An Information Provision Framework for Performance-Based Interactive E-Learning Application for Manufacturing,” examines the effectiveness and