Design and manufacturing analysis of a window shading system

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1997.Includes bibliographical references (leaf 63).In this thesis a novel concept for a window shading system was proposed and developed. This concept was created to address issues with an existing Lutron Electronics product. Over the past year and a half, concepts have been generated, tested and refined to produce a fully functional working prototype that meets the product specifications. This thesis focuses upon a manufacturing cost analysis and redesign of a gearbox assembly for the window shading system. This is a logical next step in the product's development. An estimate for the assembly time for the current version of the gearbox assembly is found. The parts are then redesigned for improved assembly time, and hence reduced cost. The parts are also redesigned for mass production processes; injection molding, and die casting. Calculating and then comparing cost estimates for the two processes finds an injection molded integrated design the most cost effective.by Ashley Cross Wodtke.S.M

Tunable KrCI Excimer-Laser Operation for Combustion Diagnostics

Operating conditions for a tunable XeCl excimer laser have been optimized for tunable narrow-band operation at 222 nm with KrCl, formed in Kr/He/Ne/HCl gas mixtures. This wavelength is interesting for detection of nitric oxide (NO) in combustion environments. The laser emission coincides with the (1, 1) and (2, 2) bands of the NO A-X system. Laser-induced-fluorescence spectra taken in a flame show specific excitation of NO with this laser.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/86765/1/Sick42.pd

Teaching Environmental Education to Elementary Aged Home School Students at Nature Centers: An Analysis of Best Practices

The research question addressed in this project was, what are the best practices for teaching environmental education to elementary aged home school students at nature centers located in a large metropolitan area in the Upper Midwest? This study, analyzes the best practices used by several nature centers that offer home school programs, and are located in the seven counties that comprise the physical limits of the study. A nature center is a designated community space where trained professionals guide and facilitate visitors in their exploration of the natural world, and in developing a relationship with nature. Additionally, this experience should subsequently foster a sustainable connection between the people of the community and their environment. Furthermore, environmental education is required under Federal Law. The data was obtained by physically visiting/observing the grounds and facilities, and conducting in depth interviews with the environmental education practioners at five of nature centers. The research conducted has a completion study of 56%; and the compilation of these best practices is supported by the research presented in the literature review. The research included the geographical characteristics of the nature center; available recreational and adventure programs; and home school program specifics. The author reviewed Eric Anderman’s examination and analysis of the strengths and weaknesses of various research methodologies; and selected a hybrid of Action and Qualitative Research as the most appropriate method to be used. This methodology is relevant when it is conducted by teachers and examines their own practices using a holistic approach to naturalistic settings. This hybrid, or mixed method, research is applicable because environmental science is a multifaceted and complex subject. Some of the best practices reviewed by the author were: 1) time spent outside in conjunction with education correlates to far-reaching academic benefits; 2) experiential learning where a child uses all their senses in exploring and manipulating the natural world, intensifies a child’s desire to experiment; and 3) positive effects are manifested when humans experience nature’s power and grandeur. (346 words

Rotational energy compensates the energy defect in near-resonant vibration-vibration energy transfer: a state-to-state study of NO(v) + N20.

Our lack of understanding of the factors that compensate energy defects in near resonant V-V energy transfer constrains our ability to accurately predict resonance widths and, thus, the overall importance of such processes. We have carried out one of the first truly state-to-state measurements of near resonant V-V energy transfer under single collision conditions, employing the crossed molecular beams, stimulated emission pumping technique. We have varied the energy defect ΔE for the process: NO

Developing permaculture techniques for increased production and profit in sustainable year-round agriculture for beginning farmers and ranchers in southwest Iowa

The project participants researched, developed, tested and implemented technologies for year-round growing seasons designed to be viable under the growing conditions in southwest Iowa. High tunnels, alternative crops, vermiculture and collaborative producer groups were among the options tested

Inelastic scattering of H atoms from surfaces

We have developed an instrument that uses photolysis of hydrogen halides to produce nearly monoenergetic hydrogen atom beams and Rydberg atom tagging to obtain accurate angle-resolved time-of-flight distributions of atoms scattered from surfaces. The surfaces are prepared under strict ultrahigh vacuum conditions. Data from these experiments can provide excellent benchmarks for theory, from which it is possible to obtain an atomic scale understanding of the underlying dynamical processes governing H atom adsorption. In this way, the mechanism of adsorption on metals is revealed, showing a penetration–resurfacing mechanism that relies on electronic excitation of the metal by the H atom to succeed. Contrasting this, when H atoms collide at graphene surfaces, the dynamics of bond formation involving at least four carbon atoms govern adsorption. Future perspectives of H atom scattering from surfaces are also outlined