In many real-world job-shop situations, jobs are sequence dependent and the setup times for those jobs vary stochastically because of such random factors as crew skills, temporary shortage of equipment, tools and setup crews, and unexpected breakdowns of fixtures and tools during a setup operation. Assuming these random setup times to be fixed at, say, their expected values, which is often done in the extant literature, may lead to development of inefficient sequencing rules. The purpose of the present paper is to investigate the impact of setup-time variation on sequencing decisions, with normally-distributed setup times. Results show that setup-time variation has a negative impact on shop performance, but does not diminish the advantages of setup-conscious sequencing rules over conventional sequencing rules in dealing with setup times. A simulation model of a nine-machine job-shop is used in the investigation.

Increasingly, nations are engaging in smart city development projects. Smart city development aims to build urban areas with a wholesome quality of life with modern infrastructure capabilities (e.g., economic opportunities, cultural richness, and demographic-geographical balance), technological benefits (e.g., healthcare, education, government) and sustainability goals (e.g., clean, green, safe, and secure environments). This requires huge investments of resources and participation of diverse stakeholders, whose goals are often ambiguous and conflicting. It is not unusual that many of these projects are delayed because of a lack of consensus, which further adds unnecessary social costs and a waste of time and efforts. In this sense, determining strategic priorities for smart city development is crucial for achieving a set of integrative purposes in terms of resource allocation and social benefits goals. This paper aims to determine strategic priorities by examining multiple cases of smart city projects in Korea, Europe, and the U.S. A hierarchical strategic framework, which shows the vision, core values and strategic goals, is developed and proposed from the case studies. Lessons and practical implications are discussed for future study.