Simulated Annealing and Threshold Accepting are two stochastic search algorithms that have been successfully used on a variety of complex and difficult problem sets. Due to their stochastic nature they are not guaranteed to produce the same result for each run. This means that these techniques actually produce a distribution...
The performance of transit networks must be measured on a regular basis to understand how well these complex systems fulfill their intended purpose and to identify potential opportunities for improvement. Measuring transit network performance is only achievable by defining a specific set of transit network performance indicators (TNPIs). Different schemes...
It is desirable for complex engineered systems to perform missions efficiently and economically, even when these missions' complex, variable, long-term operational profiles make it likely for hazards to arise. It is thus important to design these systems to be resilient so that they will actively prevent and recover from hazards...
Qualitative data analysis (QDA) is a time consuming and, potentially unreliable research activity. In qualitative research, a number of tasks must be repeated for every new research case, even if each case is closely related or is in the same area of study.
Existing QDA applications provide users with a...
Since the introduction of lean manufacturing by Toyota and publication by Womack and Jones, organizations have realized sizeable gains through lean process improvement. The spread of lean practices across organizations and industries – from manufacturing to healthcare and construction – requires adjustments of the lean process and, in the case...
Much like wind energy in its early years, marine energy has vast potential, and wave energy converter (WEC) concepts are constantly in development. Consequently, wave energy faces many challenges for expansion and has a wide-ranging design space of WEC concepts. The large design space demands new methods for understanding the...
Since the Industrial Revolution, automated systems have increasingly become a part of everyday life. Automated systems range in scale and scope from simple assists to complete robotic replacements. Inexpensive integrated circuits, sensors and microprocessors have allowed automated systems to become smaller, cheaper and more prevalent. Identifying appropriate opportunities for automation,...
As modern systems continue to increase in size and complexity, they pose significant safety and risk management challenges. System engineers and much of the government research efforts are focused on understanding the attributes and characteristics that emerge from the interactions of components and subsystems. As a result, the objective of...
Improving the understanding the relations of sustainability behaviors in manufacturing systems and actively engaging with manufacturers (especially SMEs) in sustainability efforts is key to the long-term success of U.S. industry and the natural environment. This study addresses this urgent need by establishing a systemic approach for the design of costing...
Most accidents and malfunctions in complex engineered systems are attributed to human error. However, a closer inspection would reveal that such mishaps often emerge as a result of poor design and human- and component-related vulnerabilities acting together. To fully understand and mitigate potential risks, the effects of such interactions between...