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Throughout the history of the Annular Core Research Reactor (ACRR), Transient Rod (TR) A has experienced an increased rate of failure versus the other two TRs (B and C). Either by pneumatic force or electric motor, the transient rods remove the poison rods from the ACRR core allowing for the irradiation of experiments. In order to develop causes for why TR A is failing (rod break) more often, a better understanding of the whole TR system and its components is needed. This study aims to provide a foundational understanding of how the TR pneumatic system affects the motion of the TRs and the resulting effects that the TR motion has on the neutronics of the ACRR. Transient rod motion profiles have been generated using both experimentally-obtained pressure data and by thermodynamic theory, and input into Razorback, a SNL-developed point kinetics and thermal hydraulics code, to determine the effects that TR timing and pneumatic pressure have on reactivity addition and reactivity feedback. From this study, accurate and precise TR motion profiles have been developed, along with an increased understanding of the pulse timing sequence. With this information, a safety limit within the ACRR was verified for different TR travel lengths and pneumatic system pressures. In addition, longer reactivity addition times have been correlated to cause larger amounts of reactivity feedback. The added clarity on TR motion and timing from this study will pave the way for further study to determine the cause for the increased failure rate of TR A.

published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management

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The purpose of this study was to ascertain those services and resources generally considered to be the essential parts of a mathematics learning center for students in two-year colleges by determining perceptions held by mathematics students and instructors toward these services and resources. A questionnaire sent to the mathematics department chairperson in all two-year colleges revealed 25 colleges had comprehensive mathematics learning centers (offer tutoring, testing, calculators, counseling, computer terminals, reference books, and filmstrips/slides/tapes services). Questionnaires for algebra students and their instructors were then sent to the names supplied by 19 colleges with comprehensive mathematics learning centers. Of the 837 student respondents, 38% indicated they had used the center. The most number of students had used the tutoring service. Each service was rated for the student feelings about the amount of time they used it and the help they received for satisfying their mathematical needs. The students ranked tutoring, testing, calculators, counseling, reference books, computer terminals, and filmstrips/slides/tapes services from highest to lowest respectively, for helpfulness in learning mathematics. Students gave various reasons for not using the center with 48% of the nonusers stating they knew about it but did not need to use it. The nonusers also checked the services they assumed would be of worth to them in their study of mathematics. All student responses were compared by age, college load, and outside job hours groups. Of the 33 instructor respondents, 94% recommended the tutoring service to students. The instructors rated the services for their feelings about the amount of input into each service and the support they received from each service in teaching algebra. Many instructors felt they had no input. They ranked the services for overall support provided in teaching algebra. Guidelines were formulated for the development of a college mathematics learning center. Based on this study, the conclusions were: (1) Tutoring is the most essential service. (2) Testing and calculators are very essential services. (3) The other services were less essential with computer terminals next to lowest and filmstrips/slides/tapes lowest. (4) Filmstrips/slides/tapes were more essential to instructors than to students.

This dissertation describes LABNET, a loosely-coupled network of small computers for laboratory automation and data collection. The network comprises two parts: RAPNET, the local-network operating-system-like software, and Real-time MICRODARE, an interactive language for programming automation and data-collection tasks. RAPNET provides the framework upon which application-level programs like MICRODARE execute. In addition to the usual file services and other miscellaneous system services normally supplied by a single-CPU operating system, RAPNET provides link-level message facilities, program control, and a virtual channel system. There is a means for coordinated application-level program intercommunication, the pseudo-link; pseudo-links are the means by which programs running in different CPUs or in the same CPU may be connected. To the application-level program, a pseudo-link looks just like a file or device. Real-time MICRODARE supplies an interactive programming capability which uses the facilities of RAPNET to enable a programmer to do distributed program systems for automation, simulation, and data collection. MICRODARE consists of an interactive BASIC-like job-control language, and a compiled fast-task language. The job-control language permits time and event dependent scheduling of automation and data-collection program segments. The fast-task language does simulation, signal-processing, data-collection, and control tasks at close-to-assembly-language speeds.

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