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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.
21

Undersökning av köldbryggor i balkonginfästningar / Study of thermal bridges concerning balcony connectors

Huynh, Hien, Chung, Nick Sun January 2022 (has links)
Köldbryggor innebär att en del av klimatskalet har en högre värmegenomgång än övriga delar av skalet, vilket är ett problem som ingenjörerna stöter på i varje projekt. Värmeläckage kan minimeras med hjälp av ett isolerande skikt mellan betongplattan och bjälklaget. Idag beräknas inte köldbryggan som orsakas av balkonganslutningen, utan ingår i ett påslag på 30% av den totala transmissionsförlust av byggnaden. Detta leder oss till arbetets syfte som är att undersöka varför det inte är en norm att beräkna köldbryggorna som förekommer vid balkonganslutningar.  En empirisk undersökning genomfördes med byggföretagen i Sverige, främst Skåne. Intervjun riktades till konstruktörer, energispecialister, platschefer och arbetsledare, totalt deltagande av intervjuer blev 9 varav ett företag svarade genom enkät. Utifrån intervjuerna framgick det att de två mest använda balkong typerna är den traditionella metoden där balkongen fäst genom betongklackar och balkonger som fäst genom köldbryggebrytande isolering modul.  Med hjälp av olika datorprogram kommer ovannämnda balkongtyper användas som referensobjekt där köldbryggor beräknas för att undersöka vilka faktorer och svårigheter som finns vid sådana beräkningar. Balkonger med betongklackar beräknades att ha ett värde mellan 0.4 W/mK till 1.0 W/mK medan balkonger med isoleringsmoduler beräknades till 0.023 W/mK - 0.067 W/mK, detta betyder att den traditionella klack-metoden inte håller värme lika bra som balkonger som är fästa med hjälp av isoleringsmoduler. Under beräkningar visade sig att det finns många faktorer som påverkar köldbryggor med avseende på balkonganslutningen. Exempelvis väggens innehåll, antal fönster, placering av fönster och balkongdörrar, balkongens utformning och i vissa fall är armeringensmängden okänd under planeringsfasen. Alla dessa faktorer varierar från projekt till projekt och gör det väldigt komplicerat att skapa en standardlösning som passar till varje enstaka fall. Utöver dessa faktorer så har det varit bristfälliga anvisningar på hur köldbryggor ska beräknas, detta påvisades genom att många företag som intervjuades utförde sina beräkningar på olika sätt.  Slutsatsen är att på grund av alla faktorer och svårigheter samt lågt krav på redovisning av köldbryggor i byggnader, så finns det ingen riktig anledning till att utföra så tidskrävande beräkningar under förutsättning att projektet inte syftar till forskning. Däremot tror vi att detta kommer att förändras med tiden eftersom miljön blir allt viktigare med tiden, troligtvis kommer detta leda till striktare krav gällande redovisning av köldbryggor. / Thermal bridging is the movement of heat across an object that is more conductive than other surrounding materials, which is a common problem that engineers encounter in every project. The heat leakage can be reduced by using insulation between the concrete slab and the joist. Today, the thermal bridging caused by the balcony connectors is not calculated but is included in a 30% lump sum of the total transmission losses of the building. This leads us to the purpose of the work, which is to investigate why it is not a norm to calculate the thermal bridges that occur at balcony connectors. To investigate this, an empirical survey was carried out with construction companies in Sweden, mainly Skåne. The interview was directed to engineers, energy specialists, site managers and supervisors. In total there were nine participants in the interviews and one that responded to the survey. Based on the interviews, it emerged that the two most used balcony types are the traditional method where the balcony is attached through concrete slab and joist and balconies which are attached through an insulated balcony connector. With the help of various software, thermal bridge calculations are performed to investigate factors and difficulties with the balcony connectors. Balconies with concrete slabs were calculated to have a value between 0.4 W/mK to 1.0 W/mK while balconies with insulation modules were calculated to be 0.023 W/mK to 0.067 W/mK, this means that the traditional slab method does not retain heat as well as balconies connectors with insulation modules.  The conclusion is that there is little to no reason to calculate such time-demanding calculations due to all the factors and complications. Though we believe that this will change in the future with time as the environment becomes increasingly important over time, this will probably lead to stricter requirements regarding the report of thermal bridges from Boverket.
22

Energieffektivisering av flerbostadshus i Hammarby Sjöstad : En uppföljning av projektet ”Att förnya en ny stad”

Mackegård, Moa January 2016 (has links)
In this study, efforts to improve energy efficiency in seven housing cooperatives associated to the citizens' initiative HS2020, were studied. The aim of the study was to identify and compile the energysaving measures that have been carried out by the housing cooperatives since 2013. Furthermore the study aims to investigate how much the presented measures can lower the energy consumption. Two of the housing cooperatives served as examples and the expected saving from the energy saving measures were investigated using the simulation program VIP Energy. To better understand the motives and incentives for the work, interviews were made with the board members of the housing cooperatives. The results of the study show that four out of the seven investigated cooperatives have already reached the goal of a specific energy uselower than 100 kWh/m2/year. The most effective energy-saving measuresare the installation of exhaust air heat pump and the lowering of the indoor temperature. The simulation results for the installation of heat pumps showed that the heating demand was reduced by 55.4 percent, and the specific energy consumption was reduced by 30 percent. In summary, the HS2020 is on the right track to reach the goals set for 2020, but further work is required to get there. It is of utmost importance that the cooperatives strengthen their expertise in energyrelated questions, and HS2020 has an important role in this work.
23

Att spara på värme : Energieffektiviseringar i fjärrvärmeanslutna flerbostadshus från miljonprogrammet i Uppsala

Erson, Jakob January 2016 (has links)
The purpose of this report is to survey the multi-family residential buildings that were built in the Swedish city of Uppsala during the state-funded Million Homes Program and to assess the technical potential of different energy efficiency measures that may be applied in order to improve the efficiency of the heating of these buildings. An additional purpose of this report is to discern how the entire district heating system would be affected if the proposed energy efficiency measures were implemented.   The energy efficiency measures that were examined were: improved thermal envelopes (additional insulation and energy efficient windows and doors) and installation of air-to-air heat exchangers or exhaust air heat pumps in the ventilation systems. The buildings were categorized into four different types of buildings with different properties and a model was constructed for each category.   All energy efficiency measures showed significant reductions in the amount of heating required. The measure with the best performance was improvement of thermal envelopes in combination with exhaust air heat pumps, which reduced the buildings' energy demand by about 80%. Regarding the heat demand in the entire district heating system, the reductions due to energy efficiency measures in the million homes program buildings were small. The exhaust air heat pumps showed the largest reductions in the capacity factor. Only the heat exchangers resulted in a higher capacity factor and the improvement was too small to be of interest. However, the results clearly show that saving energy in space heating is technically easily achievable.
24

Untangling neuronal diversity: a quantitative electrophysiological and morphological characterization of VIP expressing interneurons

Prönneke, Alvar 12 October 2016 (has links)
No description available.
25

Využití telefonického prodeje VIP hospitality u hokejových týmů / Analysis of the use of telephone selling VIP hospitality for hockey teams

Bursíková, Veronika January 2013 (has links)
Title: Analysis of the use of telephone selling VIP hospitality for hockey teams Objectives: The main objective of this work is to determine the current status of the use of telesales VIP for hockey teams and on the basis of the general assembly retail concept VIP hospitality over the phone. Methods: The paper used methods of analysis, inquiry and observation. The analysis method was used for the analysis of segmentation current partners of clubs, a method of questioning to determine the use of telephone sales in the sales of individual clubs and finally observation method was used to evaluate the implementation of telephone sales at the club, which it uses to sell VIP hospitality. Results: There was a finding that telesales is not widely used sales technique VIP hospitality. Clubs do not use it at all or incorrectly consequently, the inefficiently. Those who use telephone sales violate the basic principles of this type of sale and does not put enough emphasis staffing these positions. Keywords: telemarketing, VIP hospitality, sponsorship
26

ENERGIEFFEKTIVISERING– Av lamellhus byggt på sextiotalet

Sandahl, Kim, Söderberg, Richard January 2008 (has links)
<p>Title</p><p>Energy-efficiency – of slab blocks built in the sixties</p><p>Authors</p><p>Richard Sandahl and Kim Söderberg</p><p>Education</p><p>Halmstad University, Section for economy and technique Construction Engineering 180 ECTS</p><p>Supervisor</p><p>Margaretha Borgström, Universitylector construction physics, Halmstad University</p><p>Contact person at HFAB</p><p>Ulf Johansson Heating, sanitation and energy co-ordinator</p><p>Report</p><p>Examination paper at the construction engineering program is performed in cooperation with HFAB (Halmstad real estate concern Inc.)</p><p>Aim</p><p>This examinations work is done in cooperation with HFAB and there project on the block around the street Maratonvägen. HFAB:s dwelling stock on this area are going through a bigger renovation and in relation to this they are looking on the possibilities to make this building more energy efficient. That is why this examination paper has as purpose to answer the question if it is possible to make slab blocks built in the sixties more energy efficient. This is done by calculate energy efficient measures on a chosen apartment block at Maratonvägen in Halmstad, in an energy and expense perspective.</p><p>Method</p><p>The examination paper is based on different methods, mainly calculation but also qualitative conversation studies, economic calculations and literature studies. Energy calculations has been done with the computer program VIP+, which is doing the calculations based on a energy balance in consideration to the building construction. The calculation in the program is also done with consideration for climate and thermal bridges. The investment calculation is done with the pay off-method. The litterateur study is built on searches in the databases HULDA, LIBRIS and Internet. Since the development in this particularly area is progressing fast we have focused on information published after the year 2002 and forward. The dialogue interviews are founded on an interview guide. This to collect as much information as possible and be able to adjust the questions depending on the answers.</p><p>Conclusions</p><p>The conclusion that is presented in this examination paper is among others that there are good possibilities to make slab blocks built in the sixties more energy efficient. VIP+ is reliable as a calculation method for this examination paper. A change of a window with u-value 0,9W/°C is the most energy-efficient measure that we calculated and that solar-heating is a good way to provide the building with hot water.</p><p>Key word</p><p>Energy-efficiency, VIP+, energy-efficiency measures, slab blocks built in the sixties, Maratonvägen,</p>
27

ENERGIEFFEKTIVISERING– Av lamellhus byggt på sextiotalet

Sandahl, Kim, Söderberg, Richard January 2008 (has links)
Title Energy-efficiency – of slab blocks built in the sixties Authors Richard Sandahl and Kim Söderberg Education Halmstad University, Section for economy and technique Construction Engineering 180 ECTS Supervisor Margaretha Borgström, Universitylector construction physics, Halmstad University Contact person at HFAB Ulf Johansson Heating, sanitation and energy co-ordinator Report Examination paper at the construction engineering program is performed in cooperation with HFAB (Halmstad real estate concern Inc.) Aim This examinations work is done in cooperation with HFAB and there project on the block around the street Maratonvägen. HFAB:s dwelling stock on this area are going through a bigger renovation and in relation to this they are looking on the possibilities to make this building more energy efficient. That is why this examination paper has as purpose to answer the question if it is possible to make slab blocks built in the sixties more energy efficient. This is done by calculate energy efficient measures on a chosen apartment block at Maratonvägen in Halmstad, in an energy and expense perspective. Method The examination paper is based on different methods, mainly calculation but also qualitative conversation studies, economic calculations and literature studies. Energy calculations has been done with the computer program VIP+, which is doing the calculations based on a energy balance in consideration to the building construction. The calculation in the program is also done with consideration for climate and thermal bridges. The investment calculation is done with the pay off-method. The litterateur study is built on searches in the databases HULDA, LIBRIS and Internet. Since the development in this particularly area is progressing fast we have focused on information published after the year 2002 and forward. The dialogue interviews are founded on an interview guide. This to collect as much information as possible and be able to adjust the questions depending on the answers. Conclusions The conclusion that is presented in this examination paper is among others that there are good possibilities to make slab blocks built in the sixties more energy efficient. VIP+ is reliable as a calculation method for this examination paper. A change of a window with u-value 0,9W/°C is the most energy-efficient measure that we calculated and that solar-heating is a good way to provide the building with hot water. Key word Energy-efficiency, VIP+, energy-efficiency measures, slab blocks built in the sixties, Maratonvägen,
28

Utvärdering av energiberäkningsprogram : Att användas i tidigt planeringsstadium för byggnader / Evaluation of energy simulation software

Olsson, Johan January 2013 (has links)
The regulations for energy consumption are consistently getting more and morestrict. This leads to a higher customer demand for energy analysis early in the buildingdesign process. Many building planners and architects use powerful modeling softwareto visualize their projects. These digital models contain sufficient information aboutthe building’s physical characteristics for reliable energy analysis. This report evaluatesthree different energy analysis software tools and their compatibility with themodeling software Autodesk Revit Architecture. The results in the report are basedon simulations made with a fictional model in the different tools. Some of the resultsobtained from the different programs are not consistent and because of the difficultiesin evaluating these differences the usefulness is limited. Based on several criteria thesoftware have been evaluated and a recommendation for the company Tema has beenproduced. Due to the complexity of energy analysis, the software requires certainpre-knowledge of the subject by the user to perform an accurate analysis. Inconclusion, the software which is best suited for preliminary energy analysis is,according to the author, VIP-Energy because of its efficiency and credibility.
29

Increased VIP Receptor Expression Mediates CFTR Membrane Localization in Response to VIP Treatment in VIP Knockout Mice

Conrad, Dustin 23 August 2011 (has links)
Cystic Fibrosis (CF) is caused by mutations in CFTR, a protein for chloride efflux in epithelial cells. VIP is a peptide that activates CFTR and improves membrane stability; VIP has 3 receptors VPAC1, VPAC2 and PAC1 that can cause CFTR phosphorylation. VIP-knockout (VIPKO) mice experience inflammation and reduced CFTR membrane localization comparable to CF phenotypes, that’s reversible after 3 weeks of VIP treatment (VIPKOT). In this thesis western blotting showed VPAC1 and VPAC2 expression increased in VIPKO and VIPKOT lung and duodenum tissues. The expression and maturation of CFTR was unchanged in both VIPKO and VIPKOT tissues. The results showed absence of VIP caused increased receptor expression in VIPKO mice, after VIP treatment VIPKO mice maintained increased receptor expression. VIP treatment reduces inflammation and restores existing CFTR membrane localization in VIPKO mice. VIP receptor expression may be important for future treatment of CF for CFTR localization and reducing tissue inflammation.
30

Molecular and genetic analysis of neuropeptide signalling in mammalian circadian timekeeping

Hamnett, Ryan January 2017 (has links)
The suprachiasmatic nucleus (SCN) of the hypothalamus is the master mammalian pacemaker, co-ordinating the multitude of cell-autonomous circadian oscillators across the body to ensure internal synchrony, as well as maintaining an adaptive phase relationship with the light-dark cycle via projections from the retina. Intercellular communication between SCN clock neurons synchronises their oscillations, resulting in coherent output signals to the periphery. Vasoactive intestinal peptide (VIP), a neuropeptide expressed in the retinorecipient ventrolateral region of the SCN, is vital to this circuit-level co-ordination by signalling to its cognate VPAC2 receptor. In addition, VIP is important for the integration of light input into the SCN oscillation. The aims of the work presented in this thesis were to determine the roles of the VIP and VPAC2 cells in controlling circadian rhythmicity, and to elucidate the mechanisms of VIP signalling that underpin these roles. The first two experimental chapters utilise intersectional genetics and viral transduction to address separable roles for the VIP and VPAC2 cell populations. By diphtheria toxin-mediated cell ablation, or by adjusting cell-autonomous periodicity or rhythmicity specifically in these cell populations, I have identified that the VPAC2 cells are important for period setting and rhythmicity of both the SCN ex vivo and mouse behaviour in vivo, while the VIP cells play a vital role in behavioural rhythmicity and phase coherence across the SCN. The next two chapters use application of VIP to SCN slices to address mechanisms of phase-resetting through pharmacological manipulation and microarray analysis. I find that VIP has long lasting effects on all major circadian parameters of the SCN slice oscillation at both the cellular and circuit levels, and that it achieves this through a diversity of molecular pathways, in particular through cAMP/Ca2+ response elements within gene promoters. The final chapter focuses primarily on DUSP4, a negative regulator of the MAP kinase pathway that I have demonstrated to be upregulated by VIP. Here I demonstrate that DUSP4 affects the steady-state period of SCN slices, as well as influences phase shifting characteristics of both slices and mice. To conclude, the work presented here furthers our knowledge of neuropeptidergic communication in mammalian pacemaking. I have undertaken extensive characterisation of the molecular mechanisms through which the VIP neuropeptide influences SCN oscillators, and I have determined differential roles for the VIP and VPAC2 neurons in circadian timekeeping.

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