Typescript (photocopy). / Digitized by Kansas Correctional Industries

Concerns about global warming are increasing, hence, the urgency to cut carbon emissions. Reducing energy consumption, including lighting energy, is seen as the primary solution. Yet, solving the environmental factor should not come at the cost of other pillars of sustainable development. Rather, maximizing the total value of the building should be the focus. Maximizing value in the context of lighting entails improving the quality of the lighting. This study has investigated how lighting simulation could help in achieving better lighting quality. The aim of the thesis was defined as to understand the underlying architecture of lighting simulation and obtain an overview of its characteristics and applications as well as to study the use of current simulation tools. The theoretical background of lighting simulation (in the domain of Systems Engineering) was reviewed from the literature. This revealed the missing and imperfect links in the solution-to-value chain. The thesis suggests the use of a new base metric, Retinal Illuminance Map, as a solution, which in combination with black box simulation of a visual system can help repair this incomplete chain. The study of the current lighting simulation tools (Paper 1) revealed that illuminance-based metrics, luminance-based metrics, daylight availability metrics, and glare indexes are the most available performance metrics in existing lighting simulation tools. Based on usability, acceptability, availability, and previous references in the literature six software programs (Radiance, DAYSIM, Evalglare, DIALux, VELUX, and VISSLA) were selected and compared. It was found that no single tool could meet all the needs of a designer, hence, simulation tool(s) should be selected (or combined) according to the requirements of project goals and the stage of design. Building on these studies, applications of lighting simulation were identified and compiled in relation to different aspects, including performance metrics, stages of design, optimization, model integration, BIM, and parametric modeling. To obtain first-hand information about lighting designers’ experience, an online survey was conducted in Sweden (Paper 2). The results showed that lighting simulation programs were widely (90%) used in Sweden for analysis and/or rendering purposes. The majority of lighting designers considered both daylight and artificial light in their design. Factors such as ease-of use, simulation time and training had more weight than accuracy and the diversity of metrics in practitioner’s eyes. Surrogate modeling was identified as a solution for speeding up simulation time, which would also enable exploration of design solution space especially in the early design stage.

abstract: This study examines the applicability of high dynamic range (HDR) imagery as a diagnostic tool for studying lighting quality in interior environments. It originates from the limitations in lighting quality assessments, particularly from the problematic nature of measuring luminance contrast--a significant lighting quality definer. In this research, HDR imaging method is studied systematically and in detail via extensive camera calibration tests considering the effect of lens and light source geometry (i.e. vignetting, point spread and modulation transfer functions), in-camera variables (i.e. spectral response, sensor sensitivity, metering mode,), and environmental variables (i.e. ambient light level, surface color and reflectance, light source spectral power distribution) on the accuracy of HDR-image-derived luminance data. The calibration test findings are used to create camera setup and calibration guidelines for future research, especially to help minimize errors in image extracted lighting data. The findings are also utilized to demonstrate the viability of the tool in a real world setting--an office environment combining vertical and horizontal tasks. Via the quasi-experimental setup, the relationship between line of sight and perceived luminance contrast ratios are studied using HDR images. Future research can benefit from the calibration guidelines to minimize HDR-based luminance estimation errors. The proposed tool can be used and tested in different contexts and tasks with varying user groups for revising the former luminance-contrast guidelines as well as surface reflectance recommendations. / Dissertation/Thesis / Ph.D. Architecture 2011

This thesis deals with the evaluation of the quality of lighting with the usage of the latest software products used nowadays. The first part of the work is about indoor lighting, the basic requirements invested in lighting, and the basic concepts of indoor lighting. The second part includes complete search for today's computer implements for projecting, simulating, calculation and analysis of light, their functions and characteristics, including luminance analyzers based on CCD sensors and their software equipment. The last part of the work has the task to model a computer room using softwares which can be found within the territory of VUT Brno, and the task was to assess its lighting. Following this, with the help of luminance analyzer, the task is to capture the scene under different lighting conditions and to evaluate the measured data.

Compte tenu des évolutions technologiques et réglementaires actuelles, l’apparition de la technologie LED décuple lespossibilités de conception d’environnements lumineux adaptés aux attentes et besoins des usagers. Bien qu’ingénieurs etarchitectes accordent une importance croissante à la qualité de l’éclairage, peu d’éléments fondamentaux de l’environnementlumineux ont été scientifiquement identifiés au regard des attentes des clients dans le secteur de l’hôtellerie.Dans ce contexte, notre projet de recherche vise à mieux comprendre la perception des environnements lumineux de chambresd’hôtel du point de vue de l’usager, le client de l’hôtel lui-même. Nous faisons l’hypothèse que l’évaluation d’un environnementlumineux dépend à la fois des caractéristiques physiques de l’éclairage, de la situation dans laquelle il est perçu ainsi que descaractéristiques individuelles des usagers qui le perçoivent.Une méthodologie en trois phases a été construite pour tester cette hypothèse et accéder au jugement d’appréciation desusagers d’une chambre d’hôtel en situation réelle. La première phase de ce programme de recherche a permis de mettre enévidence l’importance que le client accorde à la lumière en fonction des situations d’usage qui ponctuent son séjour à l’hôtel,telles que la situation de détente ou de travail. La deuxième phase du programme a conduit à la sélection des paramètres del’éclairage pertinents dans la conception d’environnements lumineux de chambres d’hôtel, fondée sur les préférences de laclientèle. La troisième et dernière phase a permis de mesurer l’influence de la situation d’usage sur l’évaluation desenvironnements lumineux variables en termes de niveaux de lumière (30% et 100% du flux) et de températures de couleur(2700 K, 4200 K).Les résultats de cette étude ont montré que les environnements lumineux préférés des usagers sont caractérisés par une teintechaude et une faible quantité de lumière lors d’une situation de détente, contrairement à une situation de travail où une teintechaude et une forte quantité de lumière des environnements lumineux sont préférées. Des différences dans les caractéristiquesindividuelles, telles que le genre et l’âge, modulent les jugements d’appréciation.De plus, notre projet de recherche porte un enjeu méthodologique, celui de la construction d’un dispositif expérimentalpermettant la formulation et le recueil du jugement d’appréciation des usagers, relatif à l’environnement lumineux d’unechambre d’hôtel dans un contexte écologique. / Given the current changes in technologies and regulations, the emergence of LED technology multiplies the possibilities ofdesigning indoor and outdoor luminous environments adaptable to user’s needs and expectations. Although engineers andarchitects care about lighting quality, few fundamental elements of luminous environments have been evidenced as importantregarding customers’ expectations in the hospitality.In this context, our thesis aimed at better understanding the perception of light environments in hotel rooms from a users’perspective, the hotel customer itself. We assumed that the judgment of appreciation of a luminous environment depended onits lighting parameters, but also the situation during which the luminous environment was perceived and the individualcharacteristics of the users who perceived it.A three-step methodology was designed to test this hypothesis and to retrieve the judgment of appreciation of the users undera real situation in a hotel room. The first phase of this research program highlighted the importance attached by customers tolight depending on the activities undertaken during his/her stay, such as a situation of leisure or a situation of work. The secondenabled the selection of the relevant lighting parameters to design a luminous environment in a hotel room based oncustomers’ preferences. The third phase was set out to measure the influence of the situation on the assessment ofappreciation of luminous environments varying in terms of illuminance (30% of luminous flux vs 100%) and color temperature(2700K, 4200K).Overall, the users preferred the luminous environment characterized by warm white and dim light while relaxing, whereas theypreferred a warm white and bright light when working. Differences in individual characteristics like age and gender influencedthe assessment of appreciation.Moreover, the methodological issue of our project was to develop an experimental device allowing the formulation and thecollection of the users’ assessments of appreciation regarding luminous environments in a hotel room under an ecologicalcontext.

Det finns fortfarande för många hushåll i Sverige som använder mest glödljus för belysning, i form av glödlampor eller halogenlampor. Detta orsakar en väsentlig del av det onödiga överskott av koldioxidutsläpp som är en av orsakerna till den globala uppvärmningen. Därför avser detta examensarbete att försöka skapa en grönare miljö genom att studera och uppmärksamma faktorer som påverkar val av ljuskällor i belysningssammanhang. Syftet med examensarbetet är att få en ökad förståelse för hur LED-ljuset upplevs i hemmiljö. Arbetet ska visa hur LED-ljuskällans nuvarande kvalité bedöms utifrån individuella rumsupplevelser samt om ytterligare kvalitetsförbättringar behövs. Detta görs för att kunna vända allmänhetens inställning i en mer positiv riktning gentemot LED, vilket kan bidra till en mer ekologiskt hållbar miljö. För att undersöka hur LED fungerar i hemmiljö genomfördes en experimentell studie med syfte att besvara följande frågor: hur upplevs LED-ljusets kvalité jämfört med halogenljusets, hur tror man att det egna välmåendet påverkas av halogenljus respektive LED-ljus, hur påverkas rumsupplevelsen och rumskaraktären om halogenljus ersätts med LED-ljus och finns det några skillnader mellan ljusdesigners och icke ljusdesigners upplevelse av halogenljus och LED-ljus i hemmiljö? Det byggdes upp två likadana försöksrum som hade samma förutsättningar både storleksmässigt, inredningsmässigt och belysningsmässigt. Den enda skillnaden var de installerade ljuskällorna, då det användes halogenlampor i det ena rummet och LED-lampor i det andra rummet. En enkätundersökning genomfördes, resultatet analyserades och en utförlig rumsanalys gjordes. Resultatet visade att ljuset, oavsett ljuskälla, påverkade deltagarnas välmående och rumsupplevelse på olika sätt, beroende på vilken yrkesgrupp de tillhörde. Det visade sig också att skillnaden i ljuskvalitén mellan halogenljus och LED-ljus inte längre är omfattande. Dagens LED-lampor utvecklas alltså positivt och är redan en värdig ersättare till glöd- och halogenlampor. / There are still too many households in Sweden that use mostly incandescent light for lighting, using incandescent or halogen bulbs. This causes a substantial part of the unnecessary surplus of carbon-dioxide that is one of the reasons for global warming. Therefore, this degree project aims to promote a greener environment by studying and paying attention to factors that have an influence in the lighting context. The purpose of this degree project is to gain a better understanding of how the LED light is experienced in a home environment. The work will show how LED light source's current quality is evaluated based on individual room experiences, and if additional quality improvements are needed. The objective is to turn the public's attitude in a more positive direction where LED can contribute to a more ecologically sustainable environment. To investigate how LEDs are perceived in home environments an experimental study was performed which was based on the following research questions: How is LED light quality experienced compared to halogen light, how is personal wellbeing perceived in relationship to halogen and LED light, how are room experience and room character affected if halogen light is replaced by LED light in a home environment and are there any differences in these experiences between lighting designers and non lighting designers? Two identical test-rooms were used. They were identical in size, interior design and lighting design. Halogen bulbs were used in one room and LED lights were used in the other room. A survey was used to get answers to the questions above. The results have been analyzed and detailed room analysis was also made. The results showed that the light, regardless of light-source, influenced the participant's well-being and their room experience in different ways, depending on the occupational group they belonged to. It was also found that the difference in quality of light between halogen light and LED light is no longer significant. The presently available LED lights are improving and are worthy replacements for incandescent and halogen lamps.

Syfte: Det råder brist på utvärderingar av belysningsanläggningar, vilket är ett viktigt verktyg för att få förståelse för brukares upplevelse, säkerställa en anläggnings kvalitet och förvärva kunskap till kommande projekt. Inomhusmiljön påverkar i hög grad människans hälsa och välbefinnande, där belysningen är en stor påverkningsfaktor. I samverkan med konsultföretaget WSP har utvärderingar genomförts i två kontorsmiljöer på Domstolsverket i Jönköping. Målet med studien var att undersöka hur en kvalitativ och kvantitativ utvärderingsmetod stod i relation till brukarnas uppfattningar av visuell trivsel. Metod: En kombination av kvalitativa och kvantitativa metoder användes för att förstå ljusmiljöns perceptiva och fysikaliska uppbyggnad, samt förstå brukarnas subjektiva uppfattning. Använda metoder var enkät, observation utifrån PERCIFAL och mätning av luminansförhållande. Resultat: Inga tydliga samband återfanns mellan brukarnas uppfattning av visuell trivsel och observation, eller analyserade. Svaga tendenser fanns dock på att i de områden observatörerna upplevde ljusare, var även respondenternas attityd till den visuella miljön mer positiv. Både höga och låga luminansförhållanden resulterade i att respondenterna erhöll en positiv attityd till den visuella miljön och välbefinnande. En positiv inställning till ljusmiljön visade sig gynna den visuella trivseln. Starkast samband fanns mellan inställning till ljusmiljön och upplevelsen av den visuella miljön, där en positiv inställning gynnade upplevelsen av den visuella miljön. Konsekvenser: Studiens slutsats är att varken en mätning eller observation är tillräcklig att användas enskilt för att säkerställa brukarnas visuella trivsel, eller för att beskriva hur ljusmiljön uppfattas av användarna. Därför rekommenderas det att inkludera brukare vid utvärdering, och att utföra mer omfattande utvärderingar för att generera kunskap kring kopplingen mellan mätbart ljus, perceptiv upplevelse och subjektiv uppfattning av visuell trivsel. Om utvärderingar och efterkontroller som även tar hänsyn till brukarnas subjektiva uppfattning prioriteras högre i byggprocessen, kan det säkerställa att ljusmiljöer erhåller ännu högre kvalitet. Begränsningar: Att enkäten utfördes på distans kan ha påverkat resultatet, samt att respondenterna ofta valde det neutrala mittenalternativet. Vissa begrepp kan även ha tolkats på annat sätt än förväntat. Observation och mätning utfördes endast vid ett tillfälle och inte i samtliga zoner där respondenterna var positionerade. Observation och mätning utgick endast från belysningens grundinställningar och bildskärmarna var inte tända vid detta tillfälle. Valet av antalet lokaler och skillnad i användningsfrekvens kan också ha påverkat resultatet. Mätning av luminans visade sig vara mer komplext än vad som förväntats. Intervjuer hade troligtvis givit en djupare förståelse kring det undersökta fenomenet än vad som generades från enkäten. Resultatet är enbart tillämpbart i det undersökta fallet och är därmed inte generellt giltigt. / Purpose: There is a shortage of evaluations of lighting constructions, which are crucial to understand the user, ensure the environmental quality and generate knowledge for future projects. The users’ well-being is affected by the indoor environmental quality, where the lighting has a major impact. In collaboration with the consulting company WSP, evaluations have been executed in two office environments at Domstolsverket in Jönköping. The aim with the study was to investigate how one qualitative and onequantitative evaluation method is related to the users’ perceptions of visual well-being. Method: A combination of qualitative and quantitative methods were used to understand the perceptive and physical construction of the lighting environment, and to understand the users’ subjective experience. Used methods were questionnaire, observation based on PERCIFAL and luminance ratio measuring. Findings: No significant connection were found between the users’ experience of visual well-being and the observation, or between the luminance ratios. There were weak tendencies that those areas of which the observers experienced the brightest, the users experienced the visual environment in a more positive way. Both high and low luminance ratios resulted in a positive attitude to the visual environment and the wellbeing. A positive attitude to the lighting environment favored the visual well-being. The strongest connections were found between the attitude to the lighting environment and the experience of the visual environment, where a positive attitude favored the experience of the visual environment the most.  Implications: Since either the measuring or the observation hadn’t any connection to the users’ subjective experience, the conclusion of the study is that either luminance ratios or a visual evaluation individually are sufficient to ensure the users visual wellbeingor to describe how the lighting environment is experienced by the users.Therefore, it is recommended to include users in evaluations, and to execute more comprehensive evaluations to generate more knowledge regarding the connection between measurable light and perceptive and subjective experience of visual wellbeing. If this is included in the process, it might increase the quality of the lighting environment. Limitations: The questionnaire was responded to at a distance and the respondents tended to choose the neutral central option and those factors might have affected the result. Some terms might also have been interpreted in another way than expected. The observation and the measuring were only executed once, and not in all the areas where the respondents were positioned. While measuring and observing, only the most used light setting was used and the computer screens where not on. Luminance measuring was more complex than expected. Interviews might have given a deeper understanding about the investigated phenomenon than what was generated from the questionnaire.The result is only applicable in this specific case and therefore not universal.