The development of a Semi-Open Refrigeration Cycle had been shown to be of economic value to the process of crystallisation. The experimentation took the form of several bench scale experiments to develop the designs of the individual vessels that were to constitute the final pilot plant. In view of the safety hazards involved with a plant contacting Sulphuric Acid and Liquid Butane, a substantial Hazop and HAZAN study has been carried out. From this data the pilot plant was constructed, with all necessary safety features. Computer monitoring and partial computer control was installed. The pilot plant was operated as a closed loop for extended periods, to enable the production of both Iron (2) and Copper (2) Sulphates to be produced on a continuous basis. The results showed that the crystals produced are of a small size, indicative of the instantaneous chilling of the mother liquor and are not contaminated to a significant degree with the refrigerant. The thermal efficiency of the cycle was lower than expected at 80%, but improvements in insulation coupled with the redesign of the condenser, eliminating the necessity for a separator vessel, should increase this to the expected 90%.

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In this research, an analytical model for analyzing a production line consisting of a series of automated workstations with infinite buffers is developed. Automated workstations are assumed to have deterministic processing times, and independent exponentially distributed operating time between failures and repair times. The analytical model starts with existing results from a Markov chain model of two automated workstations in series, where analytical expressions are developed for the average number of jobs in the second workstation and its queue. This research focuses on the development of a set of linking equations that can be used to analyze larger systems using a two workstation decomposition approach. These linking equations utilize probabilities computed in the two-workstation Markov chain model to compute workstation parameters for a single workstation such that the first two moments of the inter-departure process from the two-workstation system and the single workstation are the same. Simulations of a number of different 3-workstation and 10-workstation systems were carried out employing a range of workstation utilizations and processing time coefficients of variation. The results from these simulations were compared with those calculated with the analytical model and various two-parameter GI/G/1 approximations and linking equations present in the literature. The analytical model resulted in an average absolute percentage difference of less than 5% in the systems studied, and performed much better than general two parameter G/G/1 approximations. The analytical model was also robust in ranking the queues in the order of the average number of jobs present in the queues. / Graduation date: 2004

The implementation of concurrent engineering into many large companies has greatly improved their product development processes. These companies have seen significant gains in quality and customer satisfaction with reduced product costs, defects, and time-to-market (Lake, 1992). Many large companies have successfully employed this relatively new product development philosophy. However, smaller companies have not yet integrated this philosophy into their product development systems with the success that larger companies have seen. With small companies composing 98% of the manufacturing firms in this country (U.S. Census Bureau, 1995), there has been a recent push for the development of implementation methods for small companies. This paper presents a five step approach that small manufacturing companies can use to implement a concurrent engineering based product development process. Our definition of a small manufacturing company is an organization with 50 or fewer employees and net annual sales of 10 million dollars or less. The first step provides a general outline for companies to use in documenting their current product development process. The second step involves comparing the company's current product development process to a concurrent engineering based product development process model that is general enough for nearly all manufacturing firms. This step also includes the use of the theory of constraints and a so-called revised theory of constraints method to further refine the process understanding and description. Third, a new methodology for designing and applying process measurements is used to provide insight into the relationships that exists between the internal and external resources, requirements and deliverables of the product development process. It is during this step that the Process Measurement Matrix (PMM) is developed. Fourth, the PMM is used in conjunction with the analytical hierarchy process or a simple ranking technique to develop relative priorities. Finally, the appropriate measurements are constructed for each subprocess in the product development process. / Graduation date: 2001

Thesis (M.S.)--West Virginia University, 2006. / Title from document title page. Document formatted into pages; contains x, 82 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 74-75).

Thesis (M.S.)--Brigham Young University. School of Technology, 2006. / Includes bibliographical references (p. 89-91).

Thesis (Ph. D.)--Rutgers University, 2009. / "Graduate Program in Industrial and Systems Engineering." Includes bibliographical references (p. 114-120).

Thesis--PlanB (M.S.)--University of Wisconsin--Stout, 2004. / Field problem. Includes bibliographical references.