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Higher production rates combined with consistent product quality and efficient energy use are the key objectives to be solved by production scheduling in the iron and steel industry. Scheduling systems used to assign activities to resources often assume the generated schedule will remain workable for the foreseeable future. Due to the dynamic nature of the steelmaking process however, it is often difficult to maintain the original short-term schedule. Unplanned events or disturbances can disrupt plans requiring modification actions or even rescheduling. Frequent rescheduling often results in instability and lack of continuity in detailed schedule execution. The schedule disturbance management is a manual process and requires many years of experience. The thesis presents a knowledge model for decision support to manage schedule disturbance in steelmaking. Literature review shows the lack of research in developing a knowledge model approach for decision making in steelmaking. Manufacturing process such as steelmaking is `process centric'. The thesis presents a novel knowledge elicitation approach called XPat, which is suitable for engineering process knowledge capture. XPat is used to identify knowledge intensive tasks in steelmaking scheduling. Managing schedule disturbance is recognised as the most knowledge intensive task within the scheduling process. Problem solving knowledge of different types of disturbance in steelmaking is captured. The thesis presents a novel task template for managing the schedule disturbance. A knowledge model of the disturbance management is developed following CommonKADS methodology. The knowledge model is implemented through a design model. The design model helps in developing a prototype decision support system (DSS) to manage schedule disturbance. The system helps the users to make right decisions and implement consistency in the management process. The XPat methodology, the knowledge model and finally the prototype are validated using a number of techniques such as case studies, workshops, paper-based simulation, and user trials. It is observed that the prototype DSS is capable of providing effective decision support to manage schedule disturbance.

Good tool management and job operating strategies will result in reduction in tool inventory and associated costs. Very little empirical research has been conducted on a Flexible Manufacturing System (FMS) as a whole in relation to its performances with tool movement approach, specifically in a dynamic job shop in a tool shared environment. This study evaluated job loading rules and tool selection policies in a tool shared environment with regards to the job shop performance as a whole. This research also examined the relationship between job loading rules and tool selection policies when tool movement approach was employed. A process oriented manufacturing system simulation procedure was used as the theoretical framework for this research, which was pursued in two phases. The first phase was focused on the development of a generalized simulation model and identification of the bottleneck conditions and merits of different simple rules. The second phase, then, was emphasized on development of bi-criterion rules and determining the "best" strategies used for bottlenecks under different simulation models and operating conditions. This research concentrated on heuristic rules. The nature of the study was observational, in which computer simulation outputs were collected and analyzed by multifactor analysis of variance, Fisher's Least Significant Difference method, and non-parametric tests. Experimental designs were used for comparing job loading rules and tool selection policies, as well as shop operating conditions. Significant differences were found among job loading rules, tool duplication levels, and tool selection policies. Furthermore, significant interaction effects were also observed between some independent factors. Job loading rules play the most important role in the system performance, specially with more tool copies. Tool selection policies affect the percent tardy jobs with single tool copy. It is noticed that in the multiple-machine and multiple-tool situations higher machine utilization can be obtained at higher tool duplication levels. The analysis of results showed that different processing time distributions also effect system performance measures. / Graduation date: 1996

Thesis (Ph. D.)--Carnegie-Mellon University, 1984. / Includes bibliographical references (p. 99-104).

Course timetabling is a time consuming problem that arise every year in each university. This is a problem that deals with assigning a large number of courses to a limited number of rooms and timeslots  while satisfying a set of predefined constraints. Most of the existing timetabling systems can only be used at the university involved in the research, as each university has its own needs and requirements that differ specifically. MyCourses software tries to make a difference by allowing each university to configure which scheduling rules to use. It provides a way to schedule courses for a whole semester rather than on weekly basis. It also gives teachers the ability  to easily specify their preferences,  facultymembers to enter various university data and also provides an optional way for scheduling university courses. The MyCourses’s automation solver uses Simulated Annealing as an optimization technique for solving the NP hard scheduling problem. Simulated Annealing searches for  a better solution as well as  it  has advantage to escape from local minimum  by allowing  to move to  worse  solution  in comparison with other algorithms which always seeks a better one.

In the microprocessor system, exploiting ILP is an important key for improving performance. As instructions scheduling mechanism is designed complicated for employing ILP more efficient, the hardware cost will become larger in opposition. In the nowadays processor, they adopt the multiple scheduler queues to issue instructions so that the hardware cost will be not larger. But in this scheduling mechanism, it could successive issue the instructions that have dependence. This situation can makes that the utilization of execution units is not saturated. In the hyperthreading architecture, the instructions in the scheduler queue have high degree of parallelism. If we can decrease the probability of situation that successive issue the instructions that have dependence, the utilization of execution units will heighten. In this paper, we propose the scheduling mechanism called as priority-scheduling buffer to replace the original scheduler queues. The scheduling mechanism will divide an original scheduler queue into multiple virtual scheduler queues according to the dependence of instructions. the instructions that have dependence will dispatch into the same virtual scheduler queue. The instructions can be issued from the ahead of different virtual scheduler queues. This can reduce the probability that successive issues the instructions that have dependence. According to result of simulation in SPEC CINT2000, we adopt the Intel Pentium 4 for basic architecture of our simulation. In the five threads executing simultaneously, the performance will increase 7.14% average that compares with the original scheduler queue.

Thesis (Ph. D.)--Lehigh University, 2001. / Includes vita. Includes bibliographical references (leaves 190-203).

"Submitted in partial fulfillment of the requirements for the degree of Master of Business Administration from the Naval Postgraduate School, December 2009." / Advisor(s): Apte, Uday. Second Reader: Franck, Raymond. "December 2009." "MBA Professional report"--Cover. Description based on title screen as viewed on January 28, 2010. Author(s) subject terms: Expeditionary logistics, training, scheduling, Unit Level Training Assessment, NAVELSG, Feeder Rates, Shipboard Cargo, Air Cargo, Cargo Handling, Cargo Handling Battalion, NCHB, Reserve Component, Cheatham Annex, Williamsburg, FATS, Arena Simulation, Capacity, Demand, Aggregate Planning, Level, Chase. Includes bibliographical references (p. 43). Also available in print.

Thesis (Ph. D.)--Lehigh University, 2003. / Includes vita. Includes bibliographical references (leaves 150-154).