Thesis (Ph. D.)--University of Michigan, 1915. / Cover title. "Reprinted from the Physical review, n.s., vol. VII, no. 4, April, 1916."

Thesis (Ph. D.)--University of Missouri-Columbia, 2003. / Typescript. Vita. Includes bibliographical references (leaves 111-118). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 2003. / Typescript. Vita. Includes bibliographical references (leaves 111-118). Also available on the Internet.

Light bulbs play an indispensable role in our lives as they provide unhindered ability to see the world even during the night. Efficiency of light bulbs is becoming increasingly important, and through this experiment, light bulb efficiencies are analyzed from measurements of relative light intensity and power input of various bulbs. Furthermore, this report is aimed to increase awareness of the efficiency advantage in fluorescent bulbs and to encourage their usage in the interest of conserving energy.

Suite à des incidents de départ de feu pendant le démantèlement d’installations nucléaires lors desdécoupes de métal a chaud, l’IRSN s’intéresse aux particules émises par les procédés de découpe etleurs effets potentiels de dégradation des barrières de confinement. L’insta1lation CAPIMIF a étédéveloppée pour reproduire des opérations de découpe de métaux représentatives de chantiers dedémantèlement. Afin de lui conférer un caractère semi analytique, cette installation a été automatisée et instrumentée avec des moyens de diagnostics permettant de caractériser en vol les particules, en termes de taille, de vitesse et de température. Les essais montrent que les particules dont la température est supérieure a 430 °C, dégradent le medium filtrant, pouvant ainsi le perforer ou diminuer localement son épaisseur, ce qui conduit à une baisse de son efficacité de filtration. Descorrélations empiriques ont été établies permettant de prévoir la perte d’efficacité de filtration. / Fire hazards while metal cutting on dismantling operations led IRSN to focus a study on incandescent particles emitted by these cutting tools and their impact on air filter. An experimentalsystem was designed, representative of dismantling operations with instrumentations adapted for inflight particles measurement, such as size, velocity and temperature. The particles are characterized from the emission source (automated cut-off grinder) and all along their path into the ventilation duct to their impact on a filter. The temperature of the particles, greater than 430 °C damages the filter medium, and may reduce the filter thickness or perforate it, which leads to a decrease of its filtration efficiency determined according to the French standard. Comparison between the characteristics of the particles and the filtration efficiency has permitted to establish empirical correlations in order to predict the loss of filtration efficiency versus the cutting parameters.

A. <u>Objectives</u>. After a careful consideration of the problems involved, the writer formulated the following objectives: (1) To determine the variation of lamp characteristics with life for various wave forms. (2) To determine the variation of lamp characteristics with voltage for various wave forms. (3) To attempt to correlate the variation of lamp characteristics to the crest factor of the voltage wave employed. B. <u>Equipment</u>. This investigation was performed on 100 watt, type A21 115-volt lamps manufactured by Sylvania Electric Products Inc. The following information obtained from the lamp manufacturer was used as a basis for all calculations. <u>Initial Lumens</u> 1635 <u>Initial Lumens Per Watt</u> 16.35 <u>Rated Average Hrs. Life</u> 750 The wave forms used were produced by means of a General Electric Sine Wave Generator, Model 15A224, consisting of a 10 horsepower, 3600 rpm, direct current motor directly coupled to five alternators. These alternators produced frequencies of 60, 120, 180, 300, and 420 cycles per second respectively. The output of the alternators were connected in series as desired by means of a specially designed switch board. The alternator fields were excited directly from the output of a 3 phase, half wave, 250 volt, 75 ampere, ignitron manufactured by the Westinghouse Electric Corporation. The value of the lamp intensity in foot-candles were read by means of a Western photronic cell. The photronic cell used was equipped with a visual-correction filter so that its response is closely similar to the visibility curve of the human eye. / Master of Science

Electricity has a long and continuing history. This paper explains the impact that electrical light had on interior design. The focus of this explanation is those interiors closest to the advent of electricity and one turn-of-the-century designer Charles Rennie Mackintosh (1868-1928). Beginning by comparing electrical light with its closest rival gaslight, this paper continues with a look at three factors in electrical history that affect its appearance in interiors. The focus narrows to the fashions appearing for the new illuminant. Finally, to understand how architects and designers applied electricity at the turn of the century, one must examine their work individually. Mackintosh is the subject of the case study embarked on in the last chapter, which examines how his lighting designs contribute to or detract from the designer's place on the cusp of Modernism.

Light - body - space - Bulb Instalation includes sixty incandescent bulbs (25 W), which flashing in certain interval. Bulbs covered all floor and their intensity of light create and change space around. Spectator has an opportunity to enter to the quickly changing field of instalation, which can confused him.

Master of Science / Department of Architectural Engineering and Construction Science / Raphael A. Yunk / Autism Spectrum Disorders, (ASD) are being diagnosed at an alarming rate. Students with ASD face many challenges in educational environments and struggle to overcome daily distractions. Students with ASD have variances in neuron connections that cause them to receive and understand their environment differently than a student without special needs. In the educational classrooms, fluorescent lighting is a significant source of extraneous stimuli that not only a source of annoyance but can also trigger common symptoms of ASD. Fluorescent fixtures economically provide an acceptable uniformity and quality of illumination, but also have disadvantages that can aggravate symptoms in students with ASD. Ballasts are required for the operation of fluorescent fixtures. These ballasts, especially if not replaced at the end of their usable life, can generate an audible hum and cyclical flickering of light. Alternative light sources, such as incandescent lamps and fixtures should be evaluated and installed not only in special needs classrooms but standard group classrooms as well. Providing additional sources or quality sources of light may help students with ASD focus on the information presented in the classroom. Traditional classroom design needs to be re-evaluated to accommodate the needs of those students with ASD to better provide a comfortable and less distracting learning environment. It is difficult to establish rigid standards for lighting designs sensitive to individuals and special needs occupants'. By understanding the symptoms of ASD and taking into account the occupants needs lighting designers will be better able to design an environment that is both comfortable and educational. This report will address the classroom environment and student considerations in order to develop parameters and design practices that will assist new lighting designers.

Thesis (Magister Technologiae - Discipline Electrical Engineering, Faculty of Engineering) -- Vaal University of Technology / Discomfort glare is a topic that has been investigated for many years without any reasonable explanation regarding its effect on the human visual system. Results of previous research concluded that established methods have a lot of similarities in implementation; but a number of differences when comparing the results of observer's evaluations with the mathematically calculated glare ratings. Therefore, an alternative method of evaluating the influence of exposure to an unshielded light source was investigated to establish a more reliable and realistic response from observers. In order to address the discrepancies of previous evaluation systems concerning observer's varying opinions regarding the level of discomfort experienced, it was decided to investigate the feasibility of evaluating the brain activity of the observers exposed to an unshielded incandescent lamp. This was done in order to facilitate the differences in each individual observer's sensitivity to bright light sources and the influence of personal taste therefore, eliminating the effect of personal interpretation. The main purpose of this study was to determine whether it would be possible to get any response regarding brain functions when an observer is exposed to a bare light source. In order to determine the pathway of visual stimuli it was necessary to investigate the operating principles of the human eye in detail. Because the eye is only an instrument that makes seeing possible; it was also important to investigate the brain and all its different functions. The part of the brain where visual interpretation takes place was indicated as the occipital lobe. This is the part of the brain monitored for any change of functional status by taking measurements with an electroencephalogram (EEG). Measurements were indeed possible; it was presented as a suppression of the alpha brain activity. During the testing procedure it was observed that the observers were not equally photosensitive. There was also a difference in the amount of alpha suppression with the observer's eyes open and closed respectively. Because the alpha rhythm has a tendency to increase with closed eyes it was much easier to notice the suppression.