Thesis (M.B.A.)--Boston University

Digitized by Kansas State University Libraries

Photocopy of typescript. / Digitized by Kansas Correctional Industries

No description available.

This research effort was directed at the development of legibility prediction models for flat-panel electronic displays used under typical office illumination (i.e., fluorescent) and various phases of daylight illumination. The models are intended to permit the manipulation of candidate display technologies and pertinent display characteristics such that legibility is maximized with respect to specified viewing conditions. Further, the legibility prediction models are intended to serve as an aid to the display designer in the intelligent selection of a display device for a known application. Critical legibility parameters were identified and relevant display measurement techniques were developed. A multiple degree of freedom daylight simulation apparatus capable of simulating the desired office and daylight illumination was designed and constructed. Reading speed performance data was collected from 14 subjects representative of both an age 18 to 30 group and an age 50 to 70 group. Each subject performed a numeral identification task using seven candidate flat-panel display technologies under 120 different symbol subtense/illumination/viewing angle arrangements. In addition, complete display characterization through microphotometric and microradiometric measurements was conducted for the seven flat-panel technologies under each of the viewing conditions. The results of the experiment revealed significant differences and complex interactions among the display technologies and viewing conditions which provided an excellent basis for the development of legibility prediction models. Extensive regression analyses were performed in which the human performance data was compared to both the critical legibility parameters and the display characterization measurements. Multiple sets of technology-based legibility prediction equations were successfully derived for each age group along with a generalized flat-panel display legibility prediction model. The models developed permit the evaluation and comparison of candidate display devices based on predicted reading speed as an indicant of legibility for a specified viewing environment. The required display characterization measurements can be collected in the field or under simulated conditions using commercially available hand-held measurement devices. In the absence of specific measures, careful estimation through comparison with similar display measurements contained in this report may be acceptable for certain applications. In their final form, the legibility prediction models serve as an aid in the evaluation and selection of electronic displays for a known application. In addition, the generalized legibility prediction equation developed holds the potential for application to other similar display technologies beyond those flat-panel candidates examined in the present study. Further, use of the models may permit the evaluation of new displays and display concepts without the immediate need for purchase, prototype construction, or complicated simulation. / Ph. D.

Master of Science / Department of Animal Sciences and Industry / Elizabeth A. E. Boyle / Light emitting diode (LED) and fluorescent (FLS) lighting effects on enhanced pork loin chops, beef longissimus dorsi and semimembranosus steaks, ground beef, and ground turkey displayed in two retail display cases set up with similar operational temperatures were evaluated using visual and instrumental color, Enterobacteriaceae (EB) and aerobic plate counts (APC), internal product and case temperatures, and thiobarbituric acid reactive substances (TBARS). Visual discoloration of the five meat products increased (P<0.05) as display time increased. Beef longissimus dorsi steaks, ground beef, and the superficial portion of beef semimembranosus steaks had less (P<0.05) visual discoloration under LED lighting than FLS. Compared to FLS, pork loin chops under LED lighting had higher (P<0.05) L* values and a lower (P<0.05) a/b ratio. The deep portion semimembranosus steak under LED was redder (P<0.05) and the superficial portion had a lower (P<0.05) a/b ratio; LED deep and superficial portion semimembranosus steaks had higher (P<0.05) saturation index values at 5.18 and 4.47, respectively, on d 0 than FLS. Pork chops under LED lighting had lower (P<0.05) APC populations than FLS by the end of display. Enterobacteriaceae populations fluctuated throughout display on ground turkey under FLS lighting while populations remained stable under LED. APC populations increased as display time increased for pork loin chops, ground beef and ground turkey, but not beef longissimus dorsi steaks possibly due to initial case-ready postmortem age. As display time increased, EB populations increased (P<0.05) for pork loin chops, ground beef and ground turkey. The internal temperature of all products, except beef longissimus dorsi steaks, was lower (P<0.05) in the LED case. FLS case temperatures were higher (P<0.05) by 0.56 to 1.11°C than LED over the duration of the study. Pork loin chops, ground turkey, and beef semimembranosus steaks had higher (P<0.05) TBARS values by 0.06 to 0.24 mg malonaldehyde/kg under LED lighting, but lighting type did not affect (P>0.05) lipid oxidation of beef longissimus dorsi steaks or ground beef. LED lighting results in lower display case temperatures, lower internal product temperatures, and extended color life; however, lipid oxidation was increased in some cuts under LED lighting.

Master of Science / Food Science Institute / Elizabeth A. Boyle / Pork preblends held for 0, 4 or 7 d were formulated into smoked sausages and analyzed for cook yield, instrumental external color, pH, salt content, proximate analysis, Warner-Bratzler shear force (WBSF), thiobarbituric acid reactive substances (TBARS), sensory analysis and purge percentage during 0, 110, 131 and 160 d display at an average 2.65 °C under fluorescent lighting. One preblend × day of display interaction was found for b* values. On display d 0, preblend d 7 was more yellow (P < 0.05) than preblend d 0 and 4; however, no differences (P > 0.05) were found for any preblends on d 110 or 160. On display d 131, preblend d 0 was more (P < 0.05) yellow than preblend d 4 but similar (P > 0.05) to preblend d 7. There was no preblend effect (P > 0.05) on any of the other attributes measured. Display day did not affect (P > 0.05) purge, pH, proximate analysis, WBSF, juiciness, saltiness or off-flavor. For color, a* and saturation index values decreased (P < 0.05) and L* increased (P < 0.05) between d 0 and 110 as well as d 110 and 131, while L*, a*, a*/b* ratio and saturation index values were similar (P > 0.05) from d 131 to 160. Hue angle value decreased from d 0 to 110 but was similar for the remaining display. A reduction (P < 0.05) in a*/b* ratio was shown from d 0 and 110 (average 0.85) to d 131 and 160 (average 0.78). There was a reduction in salt content by 0.43% and an increase in TBARS values by 0.46 mg malonaldehyde/100 g sample from d 0 compared to d 110, 131 and 160 (P < 0.05). Inconsistent differences were found for sensory panel traits bite and flavor intensity and a reduction in mouthfeel coating was found from d 0, 110 and 131 compared to 160 (P < 0.05). Therefore, preblending could be implemented without any detrimental outcome on quality or sensory attributes of skinless smoked sausage; however, as day of display increases product may become lighter, less red and more oxidized.

Daylight harvesting is an essential strategy that is often used to enhance both the design and performance of an architectural project. Windows, as crucial architectural elements, not only admit natural light into spaces but also provide the occupants with visual connections. However, the excessive usage of windows brings an uncontrolled amount of solar energy to the spaces and negatively affect the building's energy performance. When utilizing passive design strategies such as daylight harvesting, several parameters, including the electrical lighting system, can impact the outcome. The current study investigates the role of lighting systems on daylight harvesting's effectiveness and their impact on window dimension and total energy consumption. In this study, the optimum window-to-wall ratio of an open office in the presence of two different light sources (LED and fluorescent) is explored through a computer simulation method. A combination of tools including AGi32, ElumTools, OpenStudio, EnergyPlus, Radiance, and MATLAB helps to conduct the simulation and deliver optimal results. In the results and conclusion chapter, the study provides guidelines to specify optimal window percentages considering two lighting systems in each cardinal direction. Importantly, the guideline focuses only on energy performance and not on the spatial quality of the design. / Master of Architecture / Harnessing daylight with the use of windows helps to offset parts of the electric lighting needs, and decrease the total building energy consumption. This is accomplished by using glazed materials to admit daylight and lighting control systems, which can respond to the dynamic light level. However, improper implementation of a passive daylighting strategy may cause increased energy consumption. Sunlight is accompanied by solar heat radiation which can increase the HVAC load of a space and compromise the energy savings achieved by daylighting. Therefore, a balance between solar heat and light gain is required to fully take advantage of solar energy without reverse impacts. Concerning the mentioned balance, recent advancements in lighting technology question the effectiveness of natural light in reducing whole-building energy consumption. Due to the high energy efficiency of LED luminaires, lighting power consumption is rather low, even when the lighting system operates at full capacity. Therefore, it is unclear whether the solar energy coming through glazed materials works to the advantage or disadvantage of total building energy consumption. This study hypothesized that the total energy consumption of an open office with LED luminaires would be less in absence of solar energy compared to a scenario which utilizes the solar energy. A simulation-based methodology, using a combination of photometric computation and building energy simulation tools, was utilized to examine the hypothesis and explore the impacts of lighting systems on the optimum window-to-wall ratio. The results provide a helpful guideline which highlights the impact of lighting systems on window dimensions and their mutual effect on whole-building energy consumption. Although the optimum window-to-wall ratios suggested by this study only concern energy consumption, integration of them with occupants' preferences can propose an acceptable window-to-wall ratio that satisfies both design quality and performance of a building.

Thesis (B.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1982. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING / Includes bibliographical references. / by David P. Harrahy. / B.S.

M.Tech. (Environmental Health) / Fluorescent lamps, because of their mercury content, are regarded as hazardous waste and fall under the category of electrical waste. This is due to mercury's toxicological, physical, and chemical or persistence properties, which may have acute or chronic detrimental impact on human health and the environment. This study adopted a quantitative research approach, which aimed at determining how fluorescent lamps are managed in selected public schools. The investigation followed an exploratory design.This research was done under the umbrella of the World Health Organisation Collaborating Centre for Urban Health's Health, Environment and Development study. The sample population included 22 public schools, and proportionate purposive sampling was used and data was collected through the use of structured questionnaires and observation checklist. There were no formal gUidelines available for the management of fluorescent lamps in schools as a result improper handling, storage or disposal thereof, poses a health risk to the learners, employees and the environment. The outcome of this study indicated the need of formal guidelines for the management of fluorescent lamps in public schools to the Department of Education, and to produce guidelines for operational procedures.