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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Inneklimat i kontorslokaler : Fallstudie av belysning och ventilation i kontor i Västerås

Kamil, Ayhan, Aljanabi, Tabarek January 2021 (has links)
The office environment is an important part of the workers’ performance and need therefore to be designed in a pleasant and functional way. The problem is not that today’s offices do not function but rather that these need to be improved to achieve better work results. Lighting and ventilation are big parts of the office environment. In this project will three offices be examined, and these are Archus, WSP and Sweco. Purpose: This study is done to find improvement measures for these three offices based on the examination of the light and ventilation conditions. The improvements that will be suggested are mainly based on a survey but also a study on how these two factors affect the employees’ performances. Method: To perform this project was a literature study, a case study and measurement of illuminance used. A survey om how the employees experience the office environment were also conducted. Drawings provided by the office managers were used to perform calculations of the airflow. Results: The survey shows that 73.5 percent of the 68 people who answered the survey feel comfortable in the current design of the offices. The rest feel that they lack privacy and a quiet environment. In addition, 82.4 percent are happy with the lighting situation and 69.1 percent with the air quality. Archus, WSP and Sweco all meet the required guidelines set for illuminance in an office with certain deficiency. For ventilation do Archus and Sweco meet the minimum requirements for airflow, but there are small differences between the dimensioned airflow and the minimum requirement for WSP. Conclusions: The conclusion of this study is that the three studied offices lack seclusion which affects the office workers’ ability to work. The current lighting, and the ventilation in smaller rooms also contribute worsened working conditions. Good lighting conditions is required to achieve good work results. The same applies to ventilation where the air flow is deficient in certain rooms and should be regulated. / Kontorsmiljön är en viktig del i arbetarnas prestation och ska därför utformas på ett trivsamt och funktionellt sätt. Problematiken är inte att dagens kontor inte fungerar utan att dessa kan förbättras för att uppnå goda arbetsresultat. Belysning och ventilation är stora delar inom ämnet och kontoren som undersöks i detta arbete är Archus, WSP och Sweco.  Syftet med studien är att ta fram förbättringsåtgärder för tre kontorslokaler utifrån en undersökning avseende belysnings- och ventilationsförhållanden. Förbättringsförslaget bygger främst på en enkät men även en studie om hur de två faktorer spelar in i medarbetarnas presterande.  För att utföra studien tillämpades ett antal olika metoder däribland en litteraturstudie för att sätta grund till arbetet, en fallstudie där ett studiebesök till de undersökta kontoren och mätningar utfördes. Även en enkät om hur medarbetarna upplever sina kontorsmiljöer gjordes. Ritningar som tillhandahölls av ansvariga på kontoren tillämpades för att utföra beräkningar av luftflödet.  I resultat visar enkäten att 73,5% av de 68 personer som besvarade enkäten känner sig bekväma i den nuvarande utformningen men att resterande att de saknar avskildhet och tystare miljö. Utöver det trivs 82,4% med belysningen och 69,1% med luftkvalitén i dagsläget.  Archus, WSP och Sweco uppfyller de riktvärden som ställs för belysningsstyrka i kontorslokaler med vissa avvikelser. För ventilation uppfyller Archus och Sweco minimikraven för luftflödet men för WSP förekommer det skillnader mellan minimikravet och det dimensionerade luftflödet.  Diskussionen visar att vid utförandet av mätningar var det svårt att anpassa omgivningen efter önskemål vilket medförde att vissa mätvärden avviker från verkligheten. Även för beräkning av ventilation uppstod oförväntade svårigheter som att tillgång till egna instrument för luftflödesmätning saknades samt brister i ritningar.  Slutsatserna som dras för arbetet är att de tre kontoren saknar avskildhet vilket påverkar kontorsarbetarnas arbetsförmåga. Även den nuvarande belysningen samt ventilationen i mindre rum bidrar med försämrade arbetsförhållanden. För att uppnå ett gott arbetsresultat krävs god belysning i verksamheten. Samma gäller för ventilation där luftflödet brister i vissa rum och bör regleras.
32

The use of silent substitution in measuring isolated cone- & rod- human electroretinograms. An electrophysiological study of human rod- and cone- photoreceptor activity derived using silent substitution paradigm

Kommanapalli, Deepika January 2019 (has links)
After over a decade of its discovery, the Electroretinogram (ERG) still remains the objective tool that is conventionally used in assessment of retinal function in health and disease. Although there is ongoing research in developing ERG- recording techniques, interpretation and clinical applications, there is still a limited understanding on how each photoreceptor class contribute to the ERG waveform and their role and/or susceptibilities in various retinal diseases still remains unclear. Another limitation with currently used conventional testing protocols in a clinical setting is the requirement of an adaptation period which is time-consuming. Furthermore, the ERG responses derived in this manner are recorded under different stimulus conditions, thus, making comparison of these signals difficult. To address these issues and develop a new testing method, we employed silent substitution paradigm in obtaining cone- and rod- isolating ERGs using sine- and square- wave temporal profiles. The ERGs achieved in this manner were shown to be photoreceptor-selective. Furthermore, these responses did not only provide the functional index of photoreceptors but their contributions to their successive postreceptoral pathways. We believe that the substitution stimuli used in this thesis could be a valuable tool in functional assessment of individual photoreceptor classes in normal and pathological conditions. Furthermore, we speculate that this method of cone/rod activity isolation could possibly be used in developing faster and efficient photoreceptor-selective testing protocols without the need of adaptation. / Bradford School of Optometry and Vision Sciences
33

Nattbelysningens påverkan på förekomsten av nattfjärilar i Halmstads urbana grönområden.

Andersson, Nelly, Lindeberg, Richard January 2023 (has links)
Sammanfattning Nattfjärilar är en utsatt grupp när det kommer till nattbelysning, eftersom nattbelysning påverkar processer som födosök och reproduktion samt ökar deras mortalitet genom stress och ökad risk för predation. Mörka och belysta lokaler i Halmstads urbana grönområden undersöktes för att studera nattbelysningens påverkan på nattfjärilars individantal och artdiversitet. I studien visade vi på signifikanta skillnader hos både nattfjärilars individantal samt artdiversitet mellan de mörka och belysta lokalerna, där tillhörande analyser visade signifikant färre antal individer och likaså negativ trend för artdiversiteten. Analyserna visade att minskad artdiversitet och individantal i belysta lokaler inte var signifikant korrelerat med belysningsstyrkan i lokalerna. Dock finns det indikationer på att belysningsstyrkan eventuellt haft en negativ påverkan på individantalet och artdiversiteten av nattfjärilar i denna studie. Det fanns en belyst lokal som utmärkte sig med ovanligt hög diversitet där artdiversiteten var det tredje högsta uppmätta värdet i hela studien. Detta kan eventuellt bero på förekomsten av blommande buskage vilket återfanns i direkt anslutning till inventeringsområdet. Vi föreslår därför att blommande växter och buskage kan implementeras som åtgärd för att förebygga nattbelysningens påverkan på nattfjärilspopulationer. Kompletterande samt uppföljande studier av ämnet kring vilka växter som passar specifikt för nattfjärilar behövs, då det i dagsläget är ett ämne som i Sverige behöver utvecklas innan implementering av passande växter kan bli en lämplig åtgärd. / Abstract Moths are a vulnerable group when exposed to night lighting, it affects their basic drives such as foraging and reproduction and increases their mortality through stress and increased risk of predation. Dark and illuminated localities in Halmstads’ urban green areas were inventoried to study the impact of night illumination on the number of individuals and species diversity of moths. In the study, significant differences were found in the individual number of moths and species diversity between the dark and illuminated localities, which could not be significantly correlated to illuminance present in the localities. However, there were indications that illuminance may still have negatively affected the number of individuals and species diversity of moths in this study. There was one illuminated locality that stood out from the rest where species diversity was the third highest measurement from the entire study, which can possibly be attributed to the presence of flowering shrubs. Therefore we suggest that flowering shrubbery can be implemented as a measure to prevent the impact of night illumination on moth populations and becomes the basis for supplementary and follow-up studies of the subject.
34

Návrh opatření pro snížení energetické náročnosti prodejny potravin / Proposal of measures for reducing energy demands of food stores

Julinová, Patricie January 2016 (has links)
The master thesis deals with measures to reduce energy performance of grocery store building. Model of the grocery store is evaluated according to a recommended energy values specified by Czech standards and according to the real values of the actual consumption. These values are compared. Final building analysis for a proposal measures to reduce energy consumption is based on the invoices of the real consumption and on the experimental assignments. Experimental measurements are the Blower door test of the tightness of the building envelope, the measures with the thermovision camera and the measuring of the illumination intensity. The most efficient proposal is extended to the whole model network of the food shops in the Czech Republic.
35

Optimalizace světelných podmínek v budovách / Optimisation of light conditions in buildings

Vajkay, František January 2013 (has links)
Building physics as a branch of architecture must ensure an indoor comfort of each user and inhabitant of a building object. This involves, acoustics, indoor thermal conditions and among others also daylighting and artificial lighting of buildings. Light as a particle and an electromagnetic wave, is required by the different aspects of the human organism. It allows the living beings to see, influences skin and bones, the biorhythms, etc. Therefore, it is necessary for the engineering community to predict the correct illuminance and luminance levels acting insides. The thesis deals with such issues. More precisely, it assesses the quality of design tools and methodologies, either against CIE reference cases described in CIE 171/2006 and against real measurements done over the working plane of an indoor space located in the attic of Building D of the Institute of Building Structures, Faculty of Civil Engineering, Brno University of Technology, too. The tools tested throughout the solution of the dissertation did involve three computer programs: RADIANCE, WDLS v3.1 and WDLS v4.1, and one numerographical approach, namely the Daniljuk’s innovated methodology (sometimes even combined with the theories of BRS). In addition several software’s have had been created alongside the process assessment, just to mention the “RADIANCE Script”, “RADIANCE Data Evaluation Script” or “MuuLUX“. The later was written as a communication software allowing the connection of the KONICA-MINOLTA T10 illuminance meter to a computer with the aim of data collection while long term observation. The solution did also require the establishment of a measuring element for the determination of the light reflectance values of surfaces. The solutions, results and conclusions do describe how well did the design approaches deal while predicting the resulting awaited daylight factor levels in points over the working plane.

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