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.

Typescript (photocopy). / Digitized by Kansas Correctional Industries

Call number: LD2668 .T4 1978 A46 / Master of Science

Call number: LD2668 .T4 1965 H39 / Master of Science

Master of Science / Department of Architectural Engineering and Construction Science / Rhonda Wilkinson / Until recently sunlight was the primary source of illumination indoors, making perimeter fenestration essential and impacting the layout of buildings. Improvements in electric fixtures, light sources, control systems, electronic ballasts and dimming technology have influenced standard design practices to such a degree that allowing natural sunlight into a room is often seen as a liability. In the current climate of increasing energy prices and rising environmental awareness, energy conservation and resource preservation issues are a topic of governmental policy discussions for every nation on the planet. Governmental, institutional, social and economic incentives have emerged guiding the development and adoption of advanced daylighting techniques to reduce electric lighting loads in buildings used primarily during the day. A growing body of research demonstrates numerous health, occupant satisfaction, worker productivity and product sales benefits associated with natural lighting and exposure to sunlight. However, incorporating natural light into a lighting strategy is still complicated and risky as the intensity, variability and thermal load associated with sunlight can significantly impact mechanical systems and lead to serious occupant comfort issues if additional steps aren’t taken to attenuate or control direct sunlight. Fiber optic daylighting systems represent a new and innovative means of bringing direct sunlight into a building while maintaining the control ability and ease of application usually reserved for electric lighting by collecting natural light and channeling it through optical fibers to luminairies within the space. This technology has the ability to bring sunlight much deeper into buildings without impacting space layout or inviting the glare, lighting variability and heat gain issues that complicate most daylighting strategies. As products become commercially available and increasingly economically viable, these systems have the potential to conserve significant amounts of energy and improve indoor environmental quality across a variety of common applications.

Lighting accounts for nearly 20% of overall U.S. electricity consumption, 14% of U.S. residential electricity consumption, and 6% of total U.S. carbon dioxide equivalent (CO2e) emissions. A transition to alternative energy-efficient technologies could reduce this energy consumption considerably. We studied three questions related to energy efficiency lighting choices and consequences, which are: • Question 1: How large is the system-wide effect of a residential lighting retrofit with more efficient lighting technologies? • Question 2: Based on stated preference (SP) data, which factors influence consumer choices for general service light bulbs? What is the effect of the new lighting efficiency label mandated by the Federal Trade Commission? • Question 3: What can we learn about market trends and consumer choices from consumer panel data (i.e. revealed preference (RP) data) for general service light bulbs between 2004 and 2009? How can we compare the findings from SP and RP data, and which findings are robust across the two? In Chapter 2, we focus on the issue of lighting heat replacement effects. The issue is as follows: lighting efficiency goals have been emphasized in various U.S. energy efficiency policies. However, incandescent bulbs release up to 95% of input energy as heat, and it has been argued that replacing them with more efficient alternatives has a side effect in the overall building energy consumption: it increases the heating service that needs to be provided by the heating systems and decreases the cooling service that needs to be provided by the cooling systems. We investigate the net energy consumption, CO2e emissions, and saving in energy bills for single family detached houses across the U.S. as one moves towards more efficient lighting systems. In some regions, these heating and cooling effects from more efficient lighting can undermine up to 40% of originally intended primary energy savings, erode anticipated carbon savings completely, and lead to 30% less household monetary savings than intended. However, this overall effect is at most one percent of total emissions or energy consumption by a house. The size of the effect depends on various regional factors such as climate, electricity fuel mix, differences in emission factors of main energy sources used for heating and cooling, and electricity prices. Other tested factors such as building orientation, insulation level, occupancy scenario, or day length do not significantly affect the results. Then, in Chapter 3, we focus on factors that drive consumer choices for light bulbs. We collected stated preference data from a choice-based conjoint field experiment with 183 participants. We estimate discrete choice models from the data and find that politically liberal consumers have a stronger preference for compact fluorescent lighting technology and for low energy consumption. Greater willingness-to-pay for lower energy consumption and longer life is observed in conditions where estimated operating cost information was provided. Providing estimated annual cost information to consumers reduces their implicit discount rate by a factor of five, lowering barriers to adoption of energy efficient alternatives with higher up-front costs; however, even with cost information provided, consumers continue to use implicit discount rates of around 100%, which is larger than that estimated for other energy technologies. Finally, we complemented the stated preference study with a revealed preference study. This is because stated preference data alone have limitations in explaining consumer choices, as purchases are affected by many other factors that are outside of the experimenter control. We investigate consumer preferences for lighting technology based on revealed preference data between 2004 and 2009. We assess the trends in lighting sales for different lighting technologies across the country, and by store type. We find that, across the period between 2004 and 2009, sales of all general service light bulbs are almost monotonically decreasing, while CFL sales peaked in 2007. Thanks to increasing adoption of CFLs during the period, newly purchased light bulbs contributed to lowering carbon emissions and electricity consumption, while not sacrificing total produced lumens as much. We study consumer preferences for real light bulbs by estimating choice models, from which we estimate willingness-to-pay (WTP) for light bulb attributes (watt and type) and implicit discount rates (IDR) consumers adopt for their purchases. We find that the campaign for efficient bulbs in Wal-Mart in 2007 is potentially related to the peak in CFL adoption in 2007 in addition to the effects of the EISA or other factors/programs around the same period. Consumers are willing to pay, $1.84 more for a change from an incandescent bulb to a CFL and -$0.06 for 10W increase, the values which also include willingness-to-pays for corresponding changes in unobserved variables such as life and color. IDRs for four representative states range between around 230% and 330%, which is in a similar range we estimate from the choice experiment. Overall, even with energy efficiency labels, nationwide promotion of CFLs by retailers, or better availability of CFLs in the transforming residential lighting market, we see the barriers to energy efficient residential lighting are still persistent, which are reflected in high implicit discount rates observed from the models. While we can expect the EISA to be effective in lowering the barriers through regulation, it alone will not close energy efficiency gap in the residential lighting sector.

År 1947 förutspådde konstnären Thomas Wilfred att ljuskonst inom 20 år skulle bli en självklarhet inom konstvärlden. Nu, nästan 70 år senare är ljuskonst fortfarande inte en erkänd konstform eller ett definierat begrepp. Idag skapas ljuskonst av konstnärer runt om i världen med tilltagande entusiasm samtidigt som det råder en uppenbar kunskapslucka och förvirring kring ljuskonst vilket denna studie ämnar att stilla. Studien syftar till att belysa värdet och nyttan med ljuskonst som utvecklande faktor för ljusdesignsbranschen. Att konsumera konst är ett sätt att berika den inre repertoaren och inspirationskällan. De frågeställningar som undersökts är ”Vad är ljuskonst?”, ”Vad inom ljuskonst inspirerar ljusdesigners och andra som arbetar med ljus? och ”Vilka innovationer har gått från ljuskonst till ljusdesign?”. Arbetet är fokuserat till personer som arbetar med ljus och studiens definition av ljuskonst är konst som gestaltar eller skapas av ljus. Undersökningen har ett intensivt och kvalitativt upplägg och har genomförst med snöbollsmetoden i form av intervjuer via frågeformulär, som totalt besvarats av nära femtio personer. Kompletterande datainsamlingsmetoder består av massmail, telefonintervjuer och sociala medier. Primärdatan har analyserats genom sammanställning, kategorisering och sammanfattning. Det är mycket stor spridning i hur personer som arbetar med ljus beskriver ljuskonst och vad inom den de inspireras av. Vad som är ljuskonst bestäms av vem som är kreatören, var den är placerad, vad den består av och hur den upplevs. Ljuskonst har ett stort inspirationellt värde för personer som arbetar med ljus, som applicerar influenserna från ljuskonstens in i ljusdesign. Studiens slutsatser består i att ljuskonst kan skapas av både naturligt och artificiellt ljus, kan vara allt från en liten detalj till något stort och iögonfallande, skapas till en unik kontext, har ett budskap, en funktion och skiljer sig från ljusdesign i fråga om syfte och kontext. Det inom ljuskonsten som inspirerar personer som arbetar med ljus är projekt där dagsljus behandlas eller efterliknas, dess teknik och material, ljusfestivaler och andra ljusevent, verk där betraktaren kan påverka och bli en del av ljuskonsten, verk som skapar mönster, objekt med eller av ljus, scenljussättning och friheten som upplevs finnas i skapandet av ljuskonst. Studiens resultat pekar avslutningsvis mot att accentuerad arkitektur, färgat och dynamiskt ljus, ljusprojicerade mönster, neon och att placera armaturer med klassisk design för inomhusbruk i exteriöra miljöer, har gått från att betraktas som ljuskonst till ljusdesign. / In 1947 the artist Thomas Wilfred predicted that light art will become an obvious part of the art world in the next 20 years. Now, almost 70 years later, light art is still not acknowledged or defined - neither as a art form or as an expression. Artists today are creating light art all around the world with increasing enthuiaism but in point of fact there is nothing such as light art, according to the encyclopaedias. There is an obvious gap in knowledge and confusion surrounding the field of light art which this study intends to reduce. The study aims to highlight the value and benefit of light art as developing factor for the lighting design industry. Consuming art is one way of enriching the inner repertoire and inspiration. The examined issues are "What is Light art?", "What within Light art inspire Lighting designers and others who work with light?” and "Which innovations have gone from considered as Light Art to Lighting design?". The work is focused on people who work with light and the definition of light art in this study is: art that portrays or creates from light. The survey has a deep and qualitative approach and is accomplished with the snowball method throughout questionnaires, which all together were answered by nearly fifty persons. Complementary methods of collecting data consist of bulk mail, telephone interviews and the posting of the survey at social media. The primary data has been analyzed through compilation, categorization and summary. People who work with light describes light art, and also what within light art they find inspiring, in many widely different ways. In summary light art is defined by who the creator is, where it is located, what it consists of and how it is perceived. Light art inspire people working with light who apply their influences from the field of light art into the lighting design industry. The conclusions is that light art can be created by both natural and artificial light, from small details to big and eye-catching installations, has an unique context, a message, a function, and differs from lighting design in terms of purpose and context. The specific parts within light art that inspire people working with light are projects where daylight is involved, the technology and materials of the pieces, light festivals and other light events, light art pieces where the viewer can influence and become a part of it, works that create patterns or objects by light, stage lighting and the expressive freedom in the making of light art. The results indicates that accentuated architecture, colored and dynamic light, light patterns, neon and the placing of fixtures with classic design for indoor use in exterior environments, has gone from being considered as light art to lighting design.

Τα πλοία αποτελούν πιθανό στόχο ενός κεραυνικού πλήγματος. Η μελέτη και η προσομοίωση ενός κεραυνού σε δύο διαφορετικά πλοία για διάφορα σημεία πτώσης έγινε με χρήση του προγράμματος Vector Fields Opera 3D Cobham. Στο κεφάλαιο 1, γίνεται μία συνοπτική παρουσίαση των ηλεκτρικών ατμοσφαιρικών φαινομένων που οδηγούν στην εμφάνιση του κεραυνού. Επίσης, παρουσιάζονται τα διάφορα είδη κεραυνικών πληγμάτων, οι ισοδύναμες κυκλωματικές αναπαραστάσεις αυτών και η συχνότητα πτώσης κεραυνών. Στο κεφάλαιο 2, αναφέρονται οι διάφορες μέθοδοι υπολογισμού πεδιακών μεγεθών και γίνεται μια πιο εκτενής αναφορά στη μέθοδο των πεπερασμένων στοιχείων. Ακολούθως, παρουσιάζεται το πρόγραμμα Opera 3D στο οποίο έγινε η προσομοίωση του κεραυνού. Γίνονται αναφορές στης εξισώσεις και τον αλγόριθμο που χρησιμοποιεί το πρόγραμμα για τον υπολογισμό των ηλεκτρομαγνητικών μεγεθών του εκάστοτε προβλήματος. Στο κεφάλαιο 3, παρουσιάζονται οι προσομοιώσεις που πραγματοποιήθηκαν με το συγκεκριμένο πρόγραμμα. Αρχικά αναφέρεται η προσέγγιση του κεραυνικού πλήγματος με στόχο να προσαρμοσθεί στις δυνατότητες του προγράμματος. Στη συνέχεια αναφέρονται τα δύο μοντέλα πλοίων που χρησιμοποιήθηκαν (USS Somerset, HMS Albion) και τα σημεία τα οποία επιλέχθηκαν να πληγούν από κεραυνό. Επιλέχθηκαν τέσσερα σημεία σε κάθε πλοίο (πλώρη, πρύμνη, δύο κορυφές) και εφαρμόσθηκε η οριακή συνθήκη της μέγιστης τιμής του ρεύματος ενός χαρακτηριστικού κεραυνού. Σαν αποτέλεσμα προέκυψε η πυκνότητα ηλεκτρικού ρεύματος, για τις διάφορες περιπτώσεις, στο σύνολο της επιφάνειας του πλοίου και της θάλασσας. Στο κεφάλαιο 4, σχολιάζονται οι διαφορές που προέκυψαν στα δύο διαφορετικά πλοία καθώς και στα διαφορετικά σημεία πλήγματος. Επίσης παρουσιάζονται οι κανονισμοί προστασίας πλοίων, ανθρώπων και συσκευών που πρέπει να τηρούνται. Τέλος, με χρήση της μεθόδου κυλιόμενης σφαίρας γίνεται μία εκτίμηση της προστασίας έναντι κεραυνών στο κάθε πλοίο. / Naval ships are possible targets of a lightning strike. A study and simulation of a lightning strike in two different ships for different stress points is executed with Vector Fields Opera 3D Cobham. In chapter one, an overview of electrical atmospheric phenomena that lead to the appearance of lightning is given. Also, there are presented various kinds of lightning strikes, equivalent circuit representation of lightning current and frequency lightning maps. In chapter 2, various methods of calculating electromagnetic fields are presented and a more extensive report on the finite element method is described. Furthermore, the Opera 3d program is described, which simulates the lightning strike. The equations that are computed, the algorithm and the methods of calculating the electromagnetic field of Opera 3d are fully analyzed. In chapter 3, the performed simulations are presented. Firstly, the lightning approach is described. The approach was made in order to adapt to the capabilities of the program. Two ships with different dimensions (USS Somerset, HMS Albion) are designed. For the solution of the electromagnetic problem the lightning strike is approximated with the peak value of a standard strike waveform and the current density results are analyzed over the ship for four different stress points. In chapter 4, the differences that resulted from the two different ship’s simulations and different striking points are described. Several regulations of ship, human, electric devices, protection against lightning are presented and must be observed. Finally, using the rolling sphere method, lightning protection in each vessel is estimated.

Thesis (MScEng (Department of Electrical Engineering))--University of Cape Town, 2008. / Energy drives technological societies. Developing countries such as South Africa are caught between the desperate need for economic growth and the emerging obligations to the environment. Efficient technologies can be used to mitigate the impact of these seemingly conflicting requirements in urban and rural environments. In this thesis the commercially available white light-emitting diode (LED) with its inherent efficiency, longevity and mechanical strength, is used to show, that success in energy efficiency can be obtained. Two cases are used to illustrate the need for efficient demand-side technology: the electricity shortages of the Western Cape Province in South Africa and a white LED pilot project in Namulonge, Uganda. The Namulonge Solar-Home System (SHS) is analyzed with the intention of creating a more acceptable general lighting solution. The concept of appropriateness through self-determination is discussed within the context of location-specific information integrated into a design procedure. The major thrust and contribution of this thesis, however, is the design of an interior luminaire for Golden Arrow Bus Services (GABS). This is in part based on the hypothesis that application-specific information will lead to implementation and human-needs success, and is researched, designed, fabricated and then laboratory tested. The biggest challenge to be overcome was the spatial light distribution of the LED array. Thus non-imaging optical lens design became the main focus of this project as it held the key to utilizing available light while conserving the light-systems energy. Circular Fresnel and Linear Fresnel (an adaptation of the concentric design) lenses were designed. Electrical, mechanical and thermal aspects of design are also detailed. Far-field, horizontal plane detection over the specified area is used to best gain the uniformity of distribution. The four criteria namely luminance, illuminance, intensity and étendue (collection efficiency), against which each design and focal length iv configuration is compared to, are extensively explored and eventually lead to a final design. In the first designs, the area of the spatial distribution between 50% and 80% of its relative intensity is collimated. The Hybrid Circular Fresnel and Hybrid Linear Fresnel lenses now redirects the relative intensity in two areas, from 50% to 70% (creating parallel rays) and then from 70% to 100% (away from the central axis), renders a distinct difference is spatial uniformity and a reduction in the peak and offaxis located intensity. All four criteria are met, with a minor adjustment of configuration within the bus internal luminaire spacing, with the hybrid designs. It is proposed that GABS employ polished designs of the Hybrid Circular Fresnel, in any of the configurations, which have collection efficiencies ranging between 64.8% and 78.3%. / Sponsored by the Centre for Renewable and Sustainable Energy Studies, Stellenbosch University

published_or_final_version / Architecture / Doctoral / Doctor of Philosophy