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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.
211

Energieffektivisering av äldre flerbostadshus : En analys av energisparande åtgärder i 50-talsflerbostadshus klimatskal, ställd mot deras kostnad

Norell Arlid, Malin January 2018 (has links)
Äldre flerbostadshus står för en stor del av Sveriges totala energianvändning som behöver sänkas föratt minska klimatpåverkan och klara regeringsmålet om effektivare energianvändning. Examensarbetets syfte är därför att bidra till en ökad kunskap om energieffektivisering genom åtgärder i äldre byggnaders klimatskärm, och om hur åtgärder kan värderas genom energisimulering och livscykelkostnadsanalys. Målet är att identifiera vilka åtgärder som är ekonomiskt och arkitektoniskt lämpliga för äldre flerbostadshus med intresse av att bevara deras karaktär. Det är även att bedöma vilken energibesparing och livscykelkostnad de utvalda åtgärderna genererar. Ett flerbostadshus i centrala Luleå valdes ut som referensbyggnad. Byggnaden är genom sin konstruktion och design representativ för tidseran. Intressanta åtgärder samt åtgärdspaket i dess klimatskal valdes ut. Sedan utfördes en bred litteraturgenomgång om bostadsbyggandet i Sverige 1945–1964, byggnadens energianvändning, energieffektivisering av klimatskalet, de utvalda åtgärderna samt metoderna energisimulering och livscykelkostnadsanalys. Referensbyggnaden dokumenterades och en energisimuleringsmodell byggdes i programvaran IDA ICE. Den nuvarande utformningen av byggnaden simulerades och kalibrerades mot senast uppmätt normalårskorrigerad energianvändning. Sedan utfördes simuleringar för de utvalda åtgärderna och åtgärdspaketen vilka bestämts till tilläggsisolering av vindsbjälklag, byte av fönster till lågenergifönster och tätning av otätheter runt dessa, en kombination av båda tidigare åtgärder (åtgärdspaket 1), tilläggsisolering av fasad och fönsterbyte, samt en kombination av alla tre åtgärder (åtgärdspaket 2). Livscykelkostnaderna för nuläget och för implementering av de olika åtgärderna beräknades genom nuvärdeskostnadsmetoden. Även återbetalningstider beräknades genom simple-payback-metoden. Byggnadens nuvarande utformning gav efter kalibrering en simulerad energianvändning på 136,2 kWh/(m2Atemp,år); 2,9 % över det senast uppmätta normalårskorrigerade värdet. Nuvärdeskostnaden för att inte utföra någon åtgärd beräknades till ca 2 727 tkr. Åtgärderna genererade energibesparingar på 3,5–14,6 %, nuvärdeskostnader på 2 685-5 880 tkr och återbetalningstider på 7-105 år. För varje adderad åtgärd i klimatskalet ökade energibesparingen. Tilläggsisolering av vindsbjälklag visade sig vara den enda lönsamma åtgärden, då den har en nuvärdeskostnad som är lägre än att inte utföra någon åtgärd. En känslighetsanalys utfördes för kostnadsberäkningarna där diskonteringsräntan höjdes och sänktes med 2 % och energipriset höjdes med 10 %. Tilläggsisoleringav vindsbjälklag kvarstod dock som den enda lönsamma åtgärden. Åtgärderna hade kunnat generera högre procentuell energibesparing för en annan liknande byggnad. Referensbyggnaden innehåller ett stort renoverat kontor vilket ger en lägre nuvarande energianvändning och lägre procentuell energibesparing för åtgärder än om endast den äldre bostadsdelen studerats. Då Luleå har Sveriges lägsta energipris är åtgärder med hög investeringskostnad ekonomiskt svårmotiverade. Detta beror på att kostnadsbesparingarna genom minskad energianvändning blir små i förhållande till åtgärdernas investeringskostnader. Tilläggsisolering av fasad kan inte rekommenderas då åtgärden både är mycket olönsam och förändrar byggnadens uttryck väsentligt. Slutsatsen är att tilläggsisolering av vindsbjälklag är den lämpligaste åtgärden för äldre flerbostadshus, av de undersökta åtgärderna för energieffektivisering i klimatskalet. Den är arkitektoniskt lämplig med hänsyn till bevarandet av byggnaden då den inte förändrar byggnadens utseende. Den är även ekonomiskt lämplig då den har en livscykelkostnad som är lägre änalternativet att inte utföra någon åtgärd. För fortsatta studier föreslås bl.a. att undersöka hur åtgärder kan göras mer attraktiva för fastighetsägare, att kartlägga fastigheter från tidseran (skick, energianvändning, resultat av åtgärder, möjligheter) samt att utvärdera potentialen av ny teknik. / Old multifamily houses stand for a large part of Sweden’s total energy usage, which must decrease to minimize our environmental impact and to accomplish the government goal of more efficient energy usage. The aim of this master thesis is therefore to contribute to an increased knowledge on energy optimization through building envelope improvements in older buildings, and how energy efficiency measures can be evaluated through building energy simulation and life cycle cost analysis. The goal is to identify which measures that are economically and architecturally appropriate for old multifamily houses with interest in retaining their character. It is also to evaluate which energy saving and life cycle cost the selected measures generate. A multifamily house in central Luleå was selected as reference building. The building is by its construction and design representative for the era. Interesting energy efficiency measures in the building envelope were chosen. Then a wide literature study was carried out on house building in Sweden 1945-1964, building energy usage, energy efficiency through building envelope measures, the selected measures and the methods building energy simulation and life cycle cost analysis. The reference building was documented and an energy simulation model was built in the software IDA ICE. A present version of the building was simulated and calibrated to better match the latest normalised annual value. After that, simulations were performed for the selected measures; additional attic insulation, change to low energy windows and weather stripping these, a combination of both previous measures, additional facade insulation and change of windows, and a combination of all three measures. The life cycle costs of the present situation and for implementation of the different measures were calculated through the net present cost method. Also, payback times were calculated through the simple payback method. The building in its original state showed a post-calibration energy usage of 136,2 kWh/(m2Atemp,year); 2,9 % above the surveyed value. The net present cost for not performing any energy conservation measures was calculated to about 2 727 SEK. The measures generated energy savings of 3,5-14,6 %, net present costs of 2 685 -5 880 SEK and payback times of 7-105 years. For each added measure in the building envelope, the energy saving increased. Additional insulation of the attic turned out to be the only profitable measure, since its net present cost is lower than for not performing any energy conservation measure. A sensitivity analysis was performed for the cost analyses where the discount rate was raised and lowered by 2 % and the energy price raised by 10 %. However, the additional attic insulation remained as the only profitable measure. The energy conservation measures could have generated greater energy savings for a similar building. The reference building contains a large retrofitted office which lowers the present energy usage and the percental energy savings for measures compared to if only the dwelling part had been studied. Since Luleå has Sweden’s lowest energy prices, measures with high investment costs become difficult to give grounds for. This is because the cost savings achieved by their energy savings are low compared to their investment costs. Additional facade insulation cannot be recommended since it both is very unprofitable and highly changes the appearance of the building. The conclusion is that additional attic insulation is the most appropriate energy conservation measure for old multifamily houses, of selected measures in the building envelope. It can be regarded as architecturally appropriate since it does not change the building appearance. It is also economically appropriate since its life cycle cost is lower than for not performing any measure. Suggested future research includes analyzing how energy efficiency measures can be made more attractive for real estate owners, charting real estate from the era (condition, energy usage, results from measures, opportunities) and evaluating the potential of new technology within the field.
212

Natural Ventilation and Air Infiltration in Large Single‑Zone Buildings : Measurements and Modelling with Reference to Historical Churches

Hayati, Abolfazl January 2017 (has links)
Natural ventilation is the dominating ventilation process in ancient buildings like churches, and also in most domestic buildings in Sweden and in the rest of the world. These buildings are naturally ventilated via air infiltration and airing. Air infiltration is the airflow through adventitious leakages in the building envelope, while airing is the intentional air exchange through large openings like windows and doors. Airing can in turn be performed either as single-sided (one opening) or as cross flow ventilation (two or more openings located on different walls). The total air exchange affects heating energy and indoor air quality. In churches, deposition of airborne particles causes gradual soiling of indoor surfaces, including paintings and other pieces of art. Significant amounts of particles are emitted from visitors and from candles, incense, etc. Temporary airing is likely to reduce this problem, and it can also be used to adjust the indoor temperature. The present study investigates mechanisms and prediction models regarding air infiltration and open-door airing by means of field measurements, experiments in wind tunnel and computer modelling. In natural ventilation, both air infiltration and airing share the same driving forces, i.e. wind and buoyancy (indoor-outdoor temperature differences). Both forces turn out to be difficult to predict, especially wind induced flows and the combination of buoyancy and wind. In the first part of the present study, two of the most established models for predicting air infiltration rate in buildings were evaluated against measurements in three historical stone churches in Sweden. A correction factor of 0.8 is introduced to adjust one of the studied models (which yielded better predictions) for fitting the large single zones like churches. Based on field investigation and IR-thermography inspections, a detailed numerical model was developed for prediction of air infiltration, where input data included assessed level of the neutral pressure level (NPL). The model functionality was validated against measurements in one of the case studies, indicating reasonable prediction capability. It is suggested that this model is further developed by including a more systematic calibration system for more building types and with different weather conditions. Regarding airing, both single-sided and cross flow rates through the porches of various church buildings were measured with tracer gas method, as well as through direct measurements of the air velocity in a porch opening. Measurement results were compared with predictions attained from four previously developed models for single‑sided ventilation. Models that include terms for wind turbulence were found to yield somewhat better predictions. According to the performed measurements, the magnitude of one hour single-sided open-door airing in a church typically yields around 50% air exchange, indicating that this is a workable ventilation method, also for such large building volumes. A practical kind of diagram to facilitate estimation of suitable airing period is presented. The ability of the IDA Indoor Climate and Energy (IDA-ICE) computer program to predict airing rates was examined by comparing with field measurements in a church. The programs’ predictions of single-sided airflows through an open door of the church were of the same magnitude as the measured ones; however, the effect of wind direction was not well captured by the program, indicating a development potential. Finally, wind driven air flows through porch type openings of a church model were studied in a wind tunnel, where the airing rates were measured by tracer gas. At single-sided airing, a higher flow rate was observed at higher wind turbulence and when the opening was on the windward side of the building, in agreement with field measurements. Further, the airing rate was on the order of 15 times higher at cross flow than at single-sided airing. Realization of cross flow thus seems highly recommendable for enhanced airing. Calibration constants for a simple equation for wind driven flow through porches are presented. The measurements also indicate that advection through turbulence is a more important airing mechanism than pumping.   The present work adds knowledge particularly to the issues of air infiltration and airing through doors, in large single zones. The results can be applicable also to other kinds of large single-zone buildings, like industry halls, atriums and sports halls. / Naturlig ventilation är den dominerande ventilationsprocessen i äldre byggnader såsom kyrkor, och även i de flesta småhus i Sverige och övriga delar av världen. Luftinfiltration och vädring utgör viktiga komponenter i naturlig ventilation, där luftinfiltration är luftflöde genom oavsiktliga läckage i byggnadsskalet, medan vädring är avsiktligt luftutbyte genom stora öppningar såsom fönster och dörrar/portar. Vädring kan i sin tur ske ensidigt (genom en öppning) eller som tvärdrag (genom två eller flera öppningar belägna på olika ytterväggar). Det totala luftutbytet påverkar värmeförluster och inomhusluftens kvalité. I kyrkor orsakar avsättning av luftpartiklar en gradvis nedsmutsning av invändiga ytor, inklusive väggmålningar och andra konstföremål. Betydande mängder partiklar avges från besökare, tända ljus, rökelse, o.d. Tillfällig vädring kan minska detta problem, men även användas för att justera innetemperaturen. Föreliggande studie analyserar mekanismer och predikteringsmodeller gällande luftinfiltration och dörrvädring genom fältmätningar, vindtunnelförsök och datorsimuleringar. Luftinfiltration och vädring har samma drivkrafter, d.v.s. vind och termik (inne‑ute temperaturskillnader). Båda dessa drivkrafter är svåra att predicera, särskilt vindinducerade flöden och kombinationen av termik och vind. Två av de mest etablerade modellerna för luftinfiltrationsprediktering i byggnader har utvärderats via mätningar i tre kulturhistoriska stenkyrkor i Sverige. En korrigeringsfaktor av 0,8 föreslås för bättre prediktion av den ena modellen (som gav bäst resultat) gällande höga en-zonsbyggnader såsom kyrkor. En detaljerad numerisk modell är utvecklad för luftinfiltrationsprediktering, där indata baseras på fältundersökningar, inkl. IR-termografering och uppmätt av neutrala tryckplanet (NPL). Modellens funktionalitet har validerats via mätningar i en av fallstudierna och pekar på tämligen god prediktionsprestanda. Vidare utveckling av modellen föreslås, inkl. ett mer systematiskt kalibreringssystem, för olika typer av byggnader och väderförhållanden. Gällande vädring mättes både ensidigt flöde och tvärdrag genom portar i olika kyrkobyggnader med hjälp av spårgas samt direkta lufthastighetsmätningar i portöppning. Mätresultaten jämfördes med erhållna prediktioner från fyra tidigare utvecklade modeller för ensidig ventilation. De modeller som tog hänsyn till vindturbulens gav något bättre resultat. Enligt utförda mätningar medför en timmes ensidig portvädring i en kyrka cirka 50 % luftutbyte, vilket indikerar att detta är en tillämpbar ventilationsmetod, även för så pass stora byggnadsvolymer. Ett särskilt vädringsdiagram presenteras, som syftar till att underlätta uppskattning av erforderlig vädringsperiod. Vidare studerades predikteringsprestanda hos IDA Indoor Climate and Energy (IDA-ICE) simuleringsprogram avseende vädring, där simuleringsdata jämfördes med fältmätningar i en kyrka. Programmets prediktion av ensidigt luftflöde genom en öppen kyrkport var av samma storlekordning som det uppmäta; dock klarade programmet inte av att hantera inverkan av vindriktning så väl, vilket pekar på en utvecklingspotential. Avslutningsvis undersöktes vinddrivet flöde igenom portöppningar i en kyrkmodell i vindtunnel, där luftomsättningen mättes med hjälp av spårgasmetoden. Vid ensidig vädring observerades högre flöde vid högre vindturbulens och när öppningen var på vindsidan av byggnaden, i överensstämmelse med fältmätningarna. Dessutom var vädringsflödet vid tvärdrag i storleksordningen 15 högre än det vid ensidig vädring. Det verkar alltså som att man kan öka vädringstakten avsevärt om man kan åstadkomma tvärdrag. Kalibreringskonstanter presenteras också för en enkel ekvation för vinddrivet flöde genom portar. Vindtunnelstudien indikerar vidare att advektion genom turbulens är en viktigare vädringsmekanism än pumpning. Föreliggande arbete bidrar med kunskap speciellt kring luftinfiltration och vädring genom portar i höga en-zonsbyggnader. Resultaten kan även vara tillämpliga på andra typer av höga en-zonsbyggnader såsom industrihallar, atrier/ljusgårdar och idrottshallar. / Church project
213

Nationell potentialbedömning av olika energieffektiviseringsåtgärders kostnadseffektivitet i flerbostadshus : En jämförelse av olika åtgärder och analys av olika styrmedels anpassning för minskad energianvändning / National Potential Assessment Energy Efficiency and Cost-effectiveness in Multi-family Buildings : A comparison of energy efficiency measures and the conformation of Different Policy Instrument for reduced energy use

Jansson, Josef, Enell, Elisabeth January 2022 (has links)
Energianvändningen idag är den största bidragande faktorn till de globala klimatförändringarna vilket ställer krav på mer hållbar och resurseffektiv energihantering. I Sverige står sektorn bostäder och service för ca 40 % av den slutgiltiga energianvändningen motsvarande 144 TWh. För att nå en mer hållbar byggnadssektor har EU i direktivet för Byggnaders Energiprestanda satt målet att byggnadssektorn ska vara fossilfri till 2050, samt beslutat att varje medlemsstat ska etablera en långsiktig renoveringsstrategi. Nationellt finns därmed målet att minska den totala energianvändningen per uppvärmd area med 50 % till 2050 jämfört med 1995. Detta innebär att omfattande energieffektiviseringsåtgärder (EEÅ) behöver implementeras i Sveriges byggnadsbestånd. I examensarbetet jämförs den nationella potentialen avseende energibesparing, kostnadseffektivitet samt utsläppsreduktion av koldioxidekvivalenter (CO2eq) för olika energieffektiviseringsåtgärder (EEÅ) kopplade till uppvärmning och tappvarmvattenanvändning i flerbostadshus. Vidare undersöks även hur väl anpassade befintliga styrmedel är för de studerade EEÅ. För att besvara frågeställningarna har sex olika typhus tagits fram vilka är representativa för Sveriges bestånd av flerbostadshus. Dessa byggnader har modellerats i programvaran IDA ICE och energisimuleringar har genomförts för att undersöka effekterna av samtliga EEÅ. Vidare, styrmedel kopplade till energieffektivisering av flerbostadshus har analyserats och dess innebörd för olika EEÅ granskats. Resultatet visar att inom det svenska flerbostadshusbeståndet har installation av spillvattenvärmeåtervinning och FTX störst tekniskt möjlig energibesparingspotential med en årlig nationell energibesparingspotential på 5,3 TWh respektive 4,7 TWh. Isolering av tak är den EEÅ med högst kostnadseffektivitet per sparad energienhet, 334–579 SEK/MWh beroende på klimatzon, följt av spillvattenvärmeåtervinning och FTX som har en kostnadseffektivitet på 1267–1503 SEK/MWh respektive 1882–3587 SEK/MWh. Takisolering är även den EEÅ som är mest kostnadseffektiv för utsläppsminskning av koldioxidekvivalenter följt av spillvattenvärmeåtervinning och FTX. För takisolering är kostnadseffektiviteten 5,9–10,3 tSEK/ton CO2eq, 28,2–33,5 tSEK/ton CO2eq för spillvattenvärmeåtervinning och 39,5–93 tSEK/ton CO2eq för installation av FTX. Utifrån de styrmedel som studerats konstateras det att befintliga styrmedel för energieffektivisering i flerbostadshus inkluderar konventionella EEÅ men att det finns bristfällig information och krav gällande återvinning av värme från spillvatten trots åtgärdens höga energibesparingspotential och kostnadseffektivitet. Bättre kunskap och information gällande kostnadseffektiviteten för olika EEÅ kan leda till mer resurseffektiva åtgärdsförslag från energiexperter och även öka renoveringstakten. / Today's energy use is the largest contributing factor to global climate change, which calls for a more sustainable and resource-efficient energy management. In Sweden, the residential and service sector accounts for about 40% of the final energy use, corresponding to 144 TWh. To achieve a more sustainable building sector, the European Commission has set a target in the Energy Efficiency Directive that the building sector should be fossil-free by 2050 and decided that every Member State should establish a long-term renovation strategy. Nationally, there is a target to reduce the total energy use per heated area by 50% by 2050. This requires a large-scale implementation of energy efficiency measures (EEMs) in Sweden's building stock. This master thesis compares the national potential regarding energy saving, cost-effectiveness and emission reduction of carbon dioxide equivalents (CO2eq) for various EEMs linked to heating and domestic hot water use in multi-family buildings. Furthermore, it is also examined how well-adjusted existing policy instruments are to the studied EEMs. To answer the research questions, six different reference buildings, which are representative of Sweden’s stock of multi-family buildings, have been developed. These buildings have been modeled using the software IDA ICE and energy simulations have been carried out to investigate the effects for all EEMs. Policy instruments regarding energy efficiency in multi-family buildings have been analyzed and their significance for various EEMs have been investigated. The results show that installation of wastewater heat recovery and exhaust air heat recovery has the highest technically possible energy saving potential with an annual national saving potential of 5.3 TWh and 4.7 TWh, respectively Roof insulation is the EEM with the highest cost-effectiveness per saved energy unit, 334–579 SEK/MWh depending on climate zone, followed by wastewater heat recovery with a cost-effectiveness of 1267–1503 SEK/MWh and exhaust air heat recovery with 1882–3587 SEK/MWh. Roof insulation is also the EEM that is most cost-effective regarding reduced CO2eq -emissions, followed by wastewater heat recovery and exhaust air heat recovery. For roof insulation, the cost-effectiveness is 5.9–10.3 kSEK/ton CO2eq, 28.2–33.5 kSEK/ton CO2eq for wastewater heat recovery and 39.5–93 kSEK/ton CO2eq for installation of exhaust air heat recovery. Based on the studied policy instruments, it is found that the existing policy instruments for EMMs in multi-family buildings include conventional EMMS. However, there is insufficient information and requirements regarding recovery of heat from wastewater despite the measure's high energy saving potential and cost-effectiveness. Better knowledge and information regarding the cost-effectiveness of various EEMs can lead to more resource-efficient suggestions from energy experts and increase the pace of renovation.
214

Economic and environmental optimization of deep energy renovation strategies for an office building in Sweden

Sauterleute, Eva January 2022 (has links)
Energy efficiency of the building sector is a key strategy to achieve national climate goals in Sweden and other European countries. In this thesis, several renovation scenarios for a case study office building in Sweden are analysed and compared based on their energy performance, environmental impacts, and economic costs from a life cycle perspective. As a baseline, the case study building was simulated in IDA ICE and compared with the simulated renovation scenarios. For the Life Cycle Analysis (LCA) and the Life Cycle Costs (LCC), the commercially available software OneClickLCA was used. The renovation scenarios were carried out over three rounds: (i) material type scenarios where five insulation materials (glass wool, rock wool, hemp fiber, Expanded Polystyrene (EPS), and Extruded Polystyrene (XPS)) and two frame materials (wood and steel) are compared; (ii) insulation thickness optimization from economic and environmental performance perspectives (iii) comparison of combination with other typical renovation measures such as changing of windows, improving specific fan power, heat exchanger efficiencies, and lightings. The results show that glass wool gives the most economical and environmental performance, followed by rock wool and EPS. When considering other environmental indicators, hemp fiber presents the best environmental option. However, it is not competitive with traditional insulation materials from an economic perspective. The insulation thickness scenarios show different optimal economic and environmental performance points, giving total energy savings of 5 % and 9,5 %, respectively. When considering other typical energy efficiency measures, the highest impact on the energy performance was found when improving the specific fan power (SFP) and switching to LED lights with total electricity reductions (including user-based electricity consumption) of 4 % and 14 %, respectively. Conclusively, the case study showed how the electricity and heating demand of the studied office building could be reduced, and the environmental and economic consequences of the different energy-efficiency measures.
215

Energieffektivisering av miljonprogrammet i samband med våningspåbyggnad : Energisimulering i IDA ICE / Energy efficiency of the milion program in conjuction with story extension : Energy simulation usin IDA ICE

Aziz, Pola, Huynh, Kelvin January 2018 (has links)
En stor del av alla bostäder som byggdes mellan 1965-1974 brukar betecknas miljonprogrammet. Efter 40-50 års förbrukning har byggnaderna uppnått sin tekniska livslängd och är därför i behov av renovering. Detta samtidigt som bostadsbristen återstår och energikraven från myndigheter blir allt strängare i syfte att reducera bostadssektorns energianvändning samt för att uppnå ett hållbart samhälle.  Studien är baserad på ett flerbostadshus, Barytongatan 4 som är belägen i Göteborg och som är en del av projektet Kaverös etapp II. I denna studie undersöks energibesparingsåtgärder i samband med våningspåbyggnad och de regelverk som gäller vid om- och tillbyggnad enligt BBR och PBL. I simuleringsprogrammet IDA ICE kunde olika energibesparingsåtgärder studeras. Resultatet från varje enskild åtgärd och en sammansättning av dessa jämfördes därefter med den befintliga byggnadens energideklaration och statisk. Studien är koncentrerad till energisimuleringar och behandlar inga ekonomiska beräkningar. Rapporten fastställer att en våningspåbyggnad, som ökar byggnadsvolymen, är en tillbyggnad samt att allt för stora åtgärder i en befintlig byggnad klassas som en ombyggnad enligt BBR och PBL. Studien berör energibesparingsåtgärder gällande FX-system, FTX-system, balkonginglasning och solpaneler på tak. Resultatet visar att med endast få ingrepp i referenshuset, i enlighet med regelverken, kunde energianvändningen reduceras från 147 kWh/m² till 104,8 kWh/m², vilket motsvarar 28,8 procent. / A majority of houses that were built during the years 1965-1974 is usually referred to as the million program. After 40-50 years of use, the buildings have reached their technical life expectancy and need to be renovated. At the same time, the lack of housing shortage continues to exist while energy requirements from the government are becoming increasingly strict. The government maintains and run a strict policy to reduce the energy consumption of the housing sector in hope of achieving a more sustainable society. The study is based on a multi-family house located in Kaverös, Gothenburg at Barytongatan 4, which is part of the Kaverös Stage II project. In this study, energy conservation measures are investigated in connection with story extension and the applicable regulations when it comes to rebuilding and upgrading in accordance with BBR and PBL. Using the IDA ICE simulation program, different energy conservation measures could be studied. The result of each individual energy conservation measure, and a combination of these were then compared with the existing building's energy declaration and static. This study is limited to energy calculation and no financial calculations are presented The result shows that only a few interventions in the reference housing, according to the regulations BBR and PBL, can affect the energy consumption and reduce it from 147 kWh/m² to 104.8 kWh/m², which corresponds to 28.8 percent.
216

Estudo exploratório da dimensão psicobiológica do método Rolfing de integração estrutural: criação, desenvolvimento e avaliação de questionários / Exploratory studies of the psychobiological dimension of the rolfing method of structural integration: creation, development and evaluation of questionnaires

Prado, Pedro Otavio Barretto 01 September 2006 (has links)
Made available in DSpace on 2016-04-28T20:39:19Z (GMT). No. of bitstreams: 1 Pedro Otavio Barretto Prado.pdf: 2458555 bytes, checksum: 716a7b8919997d32dae998594e16854b (MD5) Previous issue date: 2006-09-01 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Empirical evidence indicates the importance of the Rolfing Method of Structural Integration for the field of Psychology. Ida P. Rolf s work is a holistic approach of organizing the human body structure in the gravitational field by rebalancing the myofascia (connective tissue) through special touch and movement education. The objective of the study described herein is to provide a systematic and consistent method for investigating the psychobiological nature of Rolfing and its intersection with the domain of psychosomatics. The author studied the power of questionnaires that had been developed for clinical research at NAPER (Brazilian Rolfing Association s Center for Clinical Practice, Research and Studies on Rolfing) and at Rolfing schools in Brazil and the United States, where the author had participated in the simultaneous elaboration, application and evaluation of the questionnaires. The questionnaires were used in connection with the Rolfing processes of 874 clients in three groups: 714 at NAPER and 160 in the Rolfing schools (55 in Brazil and 105 in the US). The questionnaire responses were evaluated both within each and among all of these three groups. The responses to closed questions were subjected to an SPSS quantitative analysis, applying statistical tests appropriate to the metrics of the questions and responses themselves. The responses to open questions were qualitatively analyzed with an SPAD.T method: for particular words, the frequencies and contexts of their uses were tabulated; then, words were grouped by conceptual affinity, and the contexts in which they appeared were analyzed. The themes that emerged from the responses, as well as their frequencies, were noted. These analyses of the data gathered in response to the questionnaires demonstrated the presence of a psychobiological dimension of Rolfing and, what s more, demonstrated to be an efficient tool for practitioners and students alike, regardless of cultural milieu. At the schools, clients perceptions concerning their quality of life before and after the Rolfing process were evaluated through the WHO-QOL questionnaire. The results were significant, and corroborated the indications of the NAPER results. The questionnaires also addressed the pre- and post-process intensity and frequency of reported pain; and indicated a significant decrease of both intensity and frequency of pain after the process. This was the case for both recent-onset and chronic pain, regardless of the location of the pain. The author posits that use of the questionnaires is, in and of itself, a mental reflexive activity an activity that makes salient the psychobiological dimension of Rolfing and it s value as a psychosomatic method. What s more, because the questionnaires further clinical, educational and research objectives simultaneously, their use highlights the relationship among those objectives. Based on his review of the evidence, the author sets forth a proposal for a revised questionnaire that comprises two levels, which could be explored independently or jointly. The first level consists of closed questions, which facilitates the collection of data for investigation. The second consists of open questions, which elicits reflection upon the psychobiological dimension of the work. Taken as a whole, this proposed questionnaire is an instrument of both research and teaching / Evidências empíricas apontam o valor do Método Rolfing de Integração Estrutural no Campo da psicologia. O trabalho de Ida P. Rolf é uma proposta holística, de organização da estrutura humana no campo gravitacional, pela reorganização do tecido miofascial, por toques especializados e educação pelo movimento. O objetivo deste trabalho é dar continuidade à investigação da natureza psicobiológica do método Rolfing e sua intersecção com o domínio da psicossomática. Estudou-se o alcance de questionários desenvolvidos em pesquisa-ação no NAPER (Núcleo de Atendimento, Pesquisa e Estudo em Rolfing, São Paulo, Brasil) e nas Escolas de Rolfing, no Brasil e nos Estados Unidos, onde o autor participou de um programa em que a elaboração, aplicação e avaliação dos questionários ocorriam simultaneamente. Os questionários foram usados nos processos de Rolfing de 874 clientes, sendo 714 do serviço de atendimento do NAPER e 160 clientes de classe das Escolas de Rolfing e, destes, 55, no Brasil e, 105, nos Estados Unidos. Foram avaliadas as respostas aos questionários das três amostras, isolada e comparativamente, tendo sido feita uma análise quantitativa das perguntas fechadas, utilizando-se o SPSS, e tendo aplicados testes estatísticos de acordo com o nível de mensuração das amostras. Realizou-se uma análise qualitativa das respostas às perguntas abertas em que se utilizou o SPAD.T, fazendo-se um levantamento das freqüências das palavras utilizadas nas respostas, agrupamentos das palavras por afinidade conceitual, além da busca e da análise do contexto em que foram utilizadas. Também foi feito o levantamento dos temas emergentes nas respostas e suas freqüências. Verificou-se que os questionários trouxeram dados que apresentam a dimensão psicobiológica do método Rolfing em todas as amostras, revelando-se eficientes no uso com profissionais formados, com alunos nas escolas e em diferentes culturas. Foram comparadas a localização, a intensidade e a periodicidade de dores relatadas, e notou-se tendência significativa para a diminuição da intensidade das dores antes e depois do processo, e diminuição na periodicidade tanto de dores recentes como crônicas em todas as localizações descritas. Nas Escolas, foi avaliada a percepção dos clientes quanto à sua Qualidade de Vida pelo WHOQOL-BREF, antes e depois do processo de Rolfing, com resultados significativos, corroborando os resultados apontados pelos questionários. O autor considera que o utilizar questionários representa atividade mental reflexiva, e que o emprego deles serve simultaneamente a propósitos de atendimento, de pesquisa e de educação, sendo o elo metodológico entre estas dimensões do trabalho, permitindo-se, assim, alavancar a percepção da dimensão psicobiológica do Rolfing e seu valor como metodologia em psicossomática. Foi feita uma revisão e uma proposta de uma bateria de questionários que possuem dois níveis: um, de perguntas fechadas e, outro, de perguntas abertas, que podem ser usados independentemente ou acoplados, e que atuam concomitantemente na investigação dos dados e eliciam a reflexão sobre a dimensão psicobiológica: um instrumento ao mesmo tempo de pesquisa e pedagógicos
217

Comparative performance of ductile and damage protected bridge piers subjected to bi-directional earthquake attack

Mashiko, Naoto January 2006 (has links)
Incremental Dynamic Analysis (IDA) procedures are advanced and then applied to a quantitative risk assessment for bridge structures. This is achieved by combining IDA with site-dependent hazard-recurrence relations and damage outcomes. The IDA procedure is also developed as a way to select a critical earthquake motion record for a one-off destructive experiment. Three prototype bridge substructures are designed according to the loading and detailing requirements of New Zealand, Japan and Caltrans codes. From these designs 30 percent reduced scale specimens are constructed as part of an experimental investigation. The Pseudodynamic test is then to control on three specimens using the identified critical earthquake records. The results are presented in a probabilistic riskbased format. The differences in the seismic performance of the three different countries' design codes are examined. Each of these current seismic design codes strive for ductile behaviour of bridge substructures. Seismic response is expected to be resulting damage on structures, which may threaten post-earthquake serviceability. To overcome this major performance shortcoming, the seismic behaviour under bi-directional lateral loading is investigated for a bridge pier designed and constructed in accordance with Damage Avoidance principles. Due to the presence of steel armoured rocking interface at the base, it is demonstrated that damage can be avoided, but due to the lack of hysteresis it is necessary to add some supplemental damping. Experimental results of the armoured rocking pier under bi-directional loading are compared with a companion ductile design specimen.
218

Uma abordagem para migração automática de código no contexto do desenvolvimento orientado a modelos

Possatto, Marcos Antonio 22 October 2013 (has links)
Made available in DSpace on 2016-06-02T19:06:10Z (GMT). No. of bitstreams: 1 5666.pdf: 3321258 bytes, checksum: c402c2fb8a619d07842991622736ea5a (MD5) Previous issue date: 2013-10-22 / Universidade Federal de Minas Gerais / Code generators play a key role in model-driven software development. They are responsible for transforming high-level assets (models) into implementation assets (code). Most generators are based on templates, which are pieces of text instrumented with code expansion elements. They receive an input and produce an output according to the template's programming. To build such template-based generators, the code of an existing implementation, already tested and validated, can be used as a reference, in a process known as code migration. With software evolution and the need for changes in the code generator, the templates start to differ from this reference implementation. In order to restablish the synchronization, additional effort is required. Tackling the challenge of keeping these assets synchronized (reference implementation and templates) is this dissertation's subject. The goal is to provide some automation to the code migration process, even if partial, in order to increase productivity in the maintenance of code generators. A mechanism was developed to make it possible to automatically reproduce changes that are performed in the reference implementation into one or more code generation templates. This mechanism was evaluated through an empirical study, yielding good performance in a controlled environment. This indicates that automation can help to reduce the effort in the maintenance of code generators in a model-driven development context. / Os geradores de código desempenham um papel fundamental no desenvolvimento de software orientado a modelos. São responsáveis pela transformação dos artefatos de alto nível de abstração (modelo) em elementos de implementação (código). Os tipos mais comuns de geradores são os baseados em template. São compostos fundamentalmente por elementos de expansão de código, que recebem uma entrada e a convertem em código, conforme a programação inserida nesses templates. O código de uma implementação já testado e validado pode servir de referência para a criação de templates, por meio de um processo conhecido como migração de código. Com a dinâmica da evolução do software e a necessidade de efetuar mudanças no gerador de código ocorre a perda de sincronismo entre os templates e esse código de referência, sendo necessário um esforço adicional para mantê-los sincronizados. O desafio de manter esses artefatos sincronizados constituiu o objetivo desta dissertação de mestrado, que proporcionou ganhos de produtividade, por meio de uma automação, ainda que parcial, desse processo. Nesse sentido, foi desenvolvido um mecanismo para propagar automaticamente as alterações introduzidas no código de referência para os templates, que reduziu o tempo e facilitou a manutenção de geradores de código que sofrem com o problema da perda de sincronismo nesses artefatos. O protótipo para a migração automática de código desenvolvido nesta dissertação foi submetido a um estudo empírico, atingindo um bom desempenho com a sua utilização na maioria das tarefas de migração de código avaliadas, o que indica que a automação pode ajudar a resolver o problema e reduzir o esforço de manutenção no desenvolvimento de software orientado a modelos.
219

Synthesis and Characterization of Functionalized Electroactive Polymers for Metal Ion Sensing

Joseph, Alex January 2014 (has links) (PDF)
Metal ion contamination in surface and ground water is a major threat as it has a direct implication on the health of terrestrial and aquatic flora and fauna. Lead (Pb2+), mercury (Hg2+), cadmium (Cd2+), nickel (Ni2+), copper (Cu2+) and cobalt (Co2+) are few of these metal ions which are classified under the high risk category. Of these, lead and mercury are of greater concern, as even nanomolar concentrations can be lethal, as they can be bio-accumulated and result in physiological as well as neurological disorders. In Asian countries like India and China, heavy metal pollution is more prevalent, as a consequence of poor governmental policies or ineffective or inadequate measures to combat this problem. In recent times, the monitoring and assessment of water pollution is a critical area of study, as it has a direct implication for its prevention and control. The major techniques used for metal ion detection are atomic absorption spectroscopy (AAS), X-ray fluorescence, ion chromatography, neutron activation, etc. Alternatively, the electrochemical, optical and electrical methods provide a platform for the fabrication of portable devices, which can facilitate the on-site analysis of samples in a rapid and cost-effective manner. This has led to a new field of research called chemical sensors or chemo sensory devices. The main aim of this study is to develop various chemosensory materials and test their response towards metal ion sensing. In this study, electroactive polymers have been synthesized for various sensor applications. The focus has been to design synthesize and test various functionalized electroactive polymers (FEAP) for the development of electrochemical, optical and chemoresistive sensors. Electroactive polymers like polyaniline, polypyrrole, polypyrrole grafted to exfoliated graphite oxide and dipyrromethene conjugated with p-(phenylene vinylene) have been synthesized and evaluated after functionalizing with metal coordinating ligands. These metal coordinating ligands were selected, in order to enhance their metal uptake capacity. Various metal ligands like imidazole, tertiary amine group, iminodiacetic acid, and dipyrromethene incorporated either in the polymer backbone or as a part of the backbone have been chosen for the metal binding. These functionalized electroactive polymers (FEAP) served as active material for metal ion sensing. The present investigation is subdivided into three sections. The first part includes design and chemical synthesis of the functionalized polymers by a series of organic reactions. The synthesis has been followed up by characterization using spectroscopic methods including NMR, FTIR, GCMS and Mass spectrometry. In the second part of the investigation, the synthesized polymer has been characterized for the changes in electronic, electric and optical properties after interaction with the selected metal ions. For this, the FEAP is allowed to interact with various metal ions and the changes in the relevant properties have been measured. This includes the study of changes in the conductivity, electronic properties like absorption or emission of the polymer, changes in the redox properties, etc. The third phase of investigation deals with the fabrication of the devices using the active FEAP. The sensor devices comprised of either films, or electrode modified with FEAP or solution of the FEAP, in combination with an appropriate technique has been used for the sensing. The major objectives are enumerated below 1. Functionalzation of polyaniline with imidazole functional group to get imidazole functionalized polyaniline (IMPANI) and study of the electronic, electrical and optical properties of the same. 2. Preparation of films of IMPANI and study of the change in conductivity of the film upon interaction with various metal ions, namely Cu2+, Co2+ and Ni2+ in their chloride form. 3. Synthesis of amine functionalized aniline monomer and chemical graft polymerization onto exfoliated graphite oxide as a substrate to synthesise the amine funtionalised polyaniline grafted to exfoliated graphite oxide (EGAMPANI). Modification of the carbon paste electrode (CPE) with EGAMPANI and study of the electrode characteristic. 4. Study of the electrode properties of EGAMPANI modified carbon paste electrode. 5. Evaluation of the EGAMPANI modified carbon paste electrode as a multi-elemental voltammetric sensor for Pb2+, Hg2+ and Cd2+ in aqueous system. 6. Functionalization of polypyrrole with iminodiacetic acid and characterization of the polymer to synthesis iminodiacetic acid functionalized polypyrrole (IDA-PPy). 7. Modification of the CPE with IDA-PPy by drop casting method and evaluation of the Pb2+ sensing properties. 8. Study of the effect of other metal ions say Hg2+, Co2+, Ni2+, Zn2+, Cu2+ and Cd2+ on the anodic stripping current of Pb2+ using EGAMPANI modified CPE. 9. Synthesis of dipyrromethene-p-(phenylene vinylene) conjugated polymer for heavy metal ion sensing. 10. Study of the changes in the optical absorption and emission properties of the polymer in THF and evaluation of the change in these optical properties upon interaction with the metal ions as analyte. The salient findings of the research work are highlighted as follows, In the first synthesis, aniline has been functionalized with imidazole group and this monomer has been chemical oxidatively polymerized to obtain imidazole functionalized polyaniline (IMPANI). The synthesized polymer possesses a nano-spherical structure, as confirmed from the morphological characterisation using scanning electron microscopy. The IMPANI has been interacted with a representative metal ion, copper (II) chloride, and the copper complexed polymer (Cu-IMPANI) has been subjected to various studies. The coordination of copper with IMPANI results in an increase of molecular weight of the polymer as a result of aggregation, as observed from dynamic light scattering measurements. Apart from this, a significant finding is the decrease of the pH of the system after copper ion coordination attesting to the generation of a secondary hydrochloride ion during the coordination of the copper to the imidazole side chain. This is further confirmed by an increase in conductivity of the Cu-IMPANI compared to IMPANI, measured using the four-probe technique. The increase of conductivity due to copper coordination is one order of magnitude higher. The films which have been prepared from IMPANI and Cu-IMPANI exhibit different morphology. The Cu-IMPANI film prepared by prior co-ordination of Cu ion with IMPANI powder shows a flaky structure, which is not preferable for the conductivity measurements, as a consequence of discontinuity in the medium. To overcome this problem, IMPANI films were initially prepared and then interacted with copper ions for a desired duration, before measurement of the conductivity. This latter procedure enabled the preparation of smooth films for the development of chemoresistive sensors. In continuation of the initial study highlighted above, IMPANI films of thickness 0.02 ± 0.001 mm have been prepared using IMPANI and PANI in DMPU in the ratio of 7:3 by mass. After exposure of the films with respective metal chlorides, such as Ni2+, Co2+ and Cu2+, a change in conductivity is observed in the concentration range of 10-2 to 1 M of metal chlorides. The sensor response may be arranged in the sequence: Ni2+ > Cu2+ > Co2+ at 1M concentration. On the contrary, films prepared from PANI-EB under identical conditions do not exhibit any appreciable change in conductivity. The optimum exposure time is determined to be 10 min for a maximum change in conductivity, after exposure to the chosen metal ions. In the second system taken up for investigation, a tertiary amine containing polyaniline (AMPANI) has been grafted to exfoliated graphite oxide. The amine containing polyaniline grafted to exfoliated graphite oxide (EGAMPANI) has been characterised for structural, morphological and elemental composition. The grafting percentage has been determined to be 7 % by weight of AMPANI on the EGO surface. The synthesized EGAMPANI (5 weight %) has been used to modify carbon paste electrode (CPE) for electrochemical sensor studies. Based on the differential pulse anodic stripping voltammetric studies, the electrochemical response may be arranged in the following sequence: Pb 2+>Cd 2+>Hg 2+ The minimum detection levels obtained are 5×10-6, 5×10-7, and 1.0×10-7 M for Hg2+, Cd2+ and Pb2+ ions respectively. In the next study, an iminodiacetic acid functionalized polypyrrole (IDA-PPy) has been synthesized and characterised for its elemental and structural properties. This has been further used to modify the CPE by drop casting method and used for the specific detection of Pb2+ in acetate buffer. Various parameters governing the electrode performance such as concentration of depositing solution, pH of depositing solution, deposition potential, deposition time, and scan rate, have been optimized to achieve maximum performance and found to be 20 μl, 4.5, -1.3 V, 11 min, 8 mV s-1 respectively for the chosen parameters. Additionally, the influence of other heavy metal ions on the lead response has been studied and it is observed that Co, Cu and Cd ions are found to be interfering. Further, the response of Cd, Co, Cu, Hg, Ni and Zn on IDA-PPy functionalized electrode has been evaluated. The selectivity of IDA-PPy modified electrode for Pb2+ is observed in the concentration range of 1 × 10-7 M and below. The IDA-PPy modified CPE shows a linear correlation for Pb2+ concentration in the range from 1×10-6 to 5×10-9 M and with a lowest limit of detection (LLOD) of 9.6×10-9 M concentration. The efficacy of the electrode for lead sensing has also been evaluated with an industrial effluent sample obtained from a lead battery manufacturing unit. The fourth synthesis pertained to the development of an optical sensor for Fe2+, and Co2+ ions. For this, dipyrromethene as a metal coordinating ligand in conjugation with p-phenylenevinylene has been synthesized and tested for its structural as well as optical properties. It is observed that the polymer shows three absorptions, namely at 294 nm, 357 nm and a major absorption observed as a broad band ranging from 484 to 670 nm. The emission spectrum of the polymer excited at 357 nm shows a characteristic blue emission with a maximum intensity centered at 425 nm. The emission quenching in the presence of various metal ions have been tested and are found to be quenched in presence of Fe2+ and Co2+ ions. All the other metal ions tested namely, Cr3+, Cu2+, and Zn2+ are not found to exhibit any change in the emission spectra below the concentration of 1 × 10-4 M. The linear correlation of the emission intensity with the concentration of the Co2+ and Fe2+ ions has been determined using Stern-Volmer plot. For Co2+ the Stern-Volmer regime is observed from 1×10-4 to 9×10-4 M concentration and the quenching constant Ksv is determined to be 8.67 ×103 M-1. For Fe2+, the linearity is found to be in the regime of 1×10-5 to 9×10-5 M and the quenching constant Ksv is determined to be 7.90 × 103 M-1. In conclusion, different electroactive polymers functionalized with metal coordinating ligands have been synthesized, characterised and evaluated for metal sensing applications. Techniques like electrochemical, optical and conductivity have been used to characterise the response of these FEAP towards metal sensing. It is can be concluded that the electrochemical sensors are more reliable for sensing especially at very low concentrations of metal ions such as Pb, Cd and other techniques like optical and conductimetric are good for detecting metal ions namely Fe, Co, Ni, Cu. The selectivity towards the metal ions is a function of the metal chelating ligand and the extent of sensitivity is dependent upon the technique employed.
220

Power System Stabilizing Controllers - Multi-Machine Systems

Gurrala, Gurunath 01 1900 (has links) (PDF)
Electrical Power System is one of the most complex real time operating systems. It is probably one of the best examples of a large interconnected nonlinear system of varying nature. The system needs to be operated and controlled with component or system problems, often with combinatorial complexity. In addition, time scales of operation and control can vary from milliseconds to minutes to hours. It is difficult to maintain such a system at constant operating condition due to both small and large disturbances such as sudden change in loads, change in network configuration, fluctuations in turbine output, and various types of faults etc. The system is therefore affected by a variety of instability problems. Among all these instability problems one of the important modes of instability is related to dynamic instability or more precisely the small perturbation oscillatory instability. Oscillations of small magnitude and low frequency (in the range of 0.1Hz to 2.5Hz) could persist for long periods, limiting the power transfer capability of the transmission lines. Power System Stabilizers (PSS) were developed as auxiliary controllers on the excitation system to improve the system damping performance by modulating the generator excitation voltage. However, the synthesis of an effective PSS for all operating conditions still remains a difficult and challenging task. The design and tuning of PSS for robust operation is a laborious process. The existing PSS design techniques require considerable expertise, the complete system information and extensive eigenvalue calculations which increases the computational burden as the system size increases. Conventional automatic voltage regulator (AVR) and PSS designs are based on linearized models of power systems which fail to stabilize the system over a wide range of operating conditions. In the last decade or so, a variety of nonlinear control techniques have become available. In this thesis, an attempt is made to explore the suitability of some of these design techniques for designing excitation controllers to enhance small perturbation stability of power systems over a wide range of operating and system conditions. This thesis first proposes a method of designing power system stabilizers based on local measurements alone, in multi-machine systems. Next, a method has been developed to analyze and quantify the small signal performance benefits of replacing the existing AVR+PSS structure with nonlinear voltage regulators. A number of new nonlinear controller designs have been proposed subsequently. These include, (a) a new decentralized nonlinear voltage regulator for multi machine power systems with a single tunable parameter that can achieve effective trade of between both the voltage regulation and small signal objectives, (b) a decentralized Interconnection and Damping Assignment Passivity Based Controller in addition to a proportional controller that can achieve all the requirements of an excitation system and (c) a Nonlinear Quadratic Regulator PSS using Single Network Adaptive Critic architecture in the frame work of approximate dynamic programming. Performance of all the proposed controllers has been analyzed using a number of multi machine test systems over a range of operating conditions.

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