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Projektera och producera en fuktsäker byggnad : En studie som klarlägger ansvarstagandet och hur kommunikationen mellan aktörer kan förbättras / Planning and produce for a humidity secure building : A research that clarifies the responsibilities and how the communication between actors in a building project can be improvedEngström, Tobias, Johansson, Jesper January 2007 (has links)
Tidigare studier visar att ansvarsfrågan för fuktsäkerheten är oklar samt att kunskapsöverföringen mellan byggprocessens olika aktörer brister. Detta kan leda till bristande fuktsäkerhet som i sin tur kan leda till hälsoproblem för de boende. Den 1 juni 2006 kom Boverket ut med en ny regelsamling (BBR) och som numer innehåller tydligare regler och omformulerade krav gällande fuktsäkert byggande. Detta arbete syftar till att redovisa risker med informationsspridningen mellan byggprocessens olika skeden samt att redovisa vilka förändringar som måste göras av aktörerna för att uppfylla senaste BBR (BFS 1993:57 med ändringar t.o.m. 2006:22). Målet med arbetet är att klarlägga ansvarsantagandet i de olika skedena av processen och att bidra med bättre rutiner för fuktsäkerheten. Arbetet grundar sig på en litteraturstudie som i teori beskriver hur aktörerna bör bedriva sitt arbete för ett fuktsäkert byggande samt redogör vilken aktör som ansvarar för vilken del av arbetet. Till arbetet har även en fallstudie genomförts, på ett byggnadsprojekt utfört i egen regi, där aktörer inom program, projektering och produktionsstadiet intervjuats. Utifrån intervjusvaren redovisas risker och förbättringsförslag med deras arbete för fuktsäkert byggande. Resultatet av fallstudien visar att det finns en del förbättringar att genomföra. I fallstudien upprättar inte beställaren några specifika fukttekniska krav. Beställaren bör upprätta en tydlig kravformulering som fastställer tekniska krav, krav på kompetens, rutiner och egenkontroller för projektet. Kravformuleringen bör också redovisa hur kraven ska verifieras samt vilken aktör som ansvarar för att kraven uppfylls. Då beställaren upprättar en sådan kravformulering minskar oklarheter i ansvarsfrågan som vilken aktör som ansvarar för vad. I fallstudien skickar konstruktör sina bygghandlingar till beställare som vidarebefordrar dessa till entreprenör. För att minimera kunskapsförluster och missförstånd, mellan projektering och produktion, så bör konstruktören träffa entreprenören för att konstruktören ska kunna överföra avsikter och information med sina bygghandlingar. I studerat projekt så tar arkitekten i första hand hjälp av materialleverantörer. Det bör kopplas fler kompetensområden, i första hand en oberoende fuktsakkunnig, till projektet i ett tidigare skede. Detta ökar möjligheten för att skapa ett välutformat program. Studerat fall är projekterat enligt tidigare BBR, men om projektet skulle vara projekterat enligt gällande BBR (BFS 1993:57 med ändringar t.o.m. 2006:22) skulle vissa förändringar behöva genomföras. För att uppfylla de nya kraven från Boverket bör en fuktsäkerhetsprojektering utföras, och till detta ska rätt kunskap anlitas om det inte redan ingår i projektet. Vidare måste entreprenören ändra sina rutiner vid mottagningskontrollen av materialet. Idag utförs inte någon fuktkvotsmätning av virket, vilket måste genomföras för att säkerhetsställa att virket inte överstiger det kritiska fukttillståndet som Boverket fastställt. / Previous studies show that the responsibility of humidity is vague and that the transference of the knowledge between the building project actors fails. This can lead to health problem among the users of the building. The first of June 2006 Boverket released a new collection with rules of construction which contains more specified rules to guarantee a secure humidity construction. The purpose with this report is to clarify what kind of changes the actors need to do, to fulfil the new rules of construction from Boverket. The purpose is also to clarify risks with how the information is transferred between actors and what kind of responsibility the actors have in the different phases of the building project. The report is based on a study of different literary works which in theory describes how the actors should pursue their work for securing humidity and also describes which actor is responsible in the different phases of the building project. For the report a specific building project is studied where different actors in different phases of the project has been interwieved. From the replys of the interwievs the risks and improvements for securing humidity is showed. The result of the study clarifies that improvements can be done in this project. The orderer of the project doesn’t create demands from humidity point of view. To minimize misunderstanding of where the responsible lies in the different phases of the project, the orderer should create demands and also clarify which actor who is responsible for fulfilling the demands. In this case the design engineer sends his building papers to the orderer of the project which further sends the paper to the contractor. To minimize misunderstandings between planning and production, the design engineer should meet up with the contractor to explain his intendancy with his building papers. In this building project the architect often listens to the supplier of material. If more knowledge is connected to an earlier phase of the building project, most of all a humidity expert, it will increase the chance for a well formed program. To fulfil the new rules of construction from Boverket the contractor needs to change his routine for the receiving of materials.
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Dehumidification effect by coupling an electroosmotic material with a desiccant interfaceMina, Ehab Mouris. January 2004 (has links)
Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2004. / Adviser: Ty A. Newell. Includes bibliographical references.
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Examination of dampness problems of a historic house/Yardım, Bülent. Tunçoku, Sarp January 2006 (has links) (PDF)
Thesis (Master)--İzmir Institute of Technology, İzmir, 2006. / Keywords: Dampness, humidity, moisture,restoration. Includes bibliographical references (leaves. 66-69).
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Aplicacao e avaliacao da tecnica de marcacao da umidade do solo com tritio artificial em pesquisas hidrogeologicas no BrasilPOLI, DORA de C.R. 09 October 2014 (has links)
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Aplicacao e avaliacao da tecnica de marcacao da umidade do solo com tritio artificial em pesquisas hidrogeologicas no BrasilPOLI, DORA de C.R. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:36:14Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:20Z (GMT). No. of bitstreams: 1
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Modelling interactions between climate and global vegetation in response to climate changeLee, S. E. January 1997 (has links)
Climate change associated with increasing concentrations of the greenhouse gas, carbon dioxide(CO2), is expected to lead to an increase in global mean temperature of between 1 and 3.5 deg C by the end of the 21st century, with regional changes in rainfall and humidity. This thesis is concerned with modelling the effects of a changing climate and atmospheric C02 concentration on global vegetation. The process-based model, DOLY (Dynamic glObal phtogeographY), is used. It is able to operate using three climate variables, two soil variables and an atmospheric CO2 concentration. Its outputs are leaf area index (LAI), and net primary productivity (NPP). The LAI and NPP values predicted by DOLY were used to run a life-form model with a climate change scenario. It was found that warming led to the spread of trees into the tundra region. The DOLY model was also coupled with the Hadley Centre general circulation model to determine the feedbacks of vegetation on climate. With a global warming of 2◦C, the global feedback of vegetation on temperature was a decrease of 0.1 deg C. However at the regional scale the feedback was +/-2 ◦C, of similar magnitude to the driving temperature change. Finally, the DOLY model was run with transient climate data from the Hadley Centre. The boreal forest moved north, and the Gobi desert and the southern steppes in the former Soviet Union shrank in area. The sensitivity of the model to its soil and climate inputs have also been analysed over a range of environments and the model has been validated with reference to satellite data and experimental data. It was found to perform well. This thesis has shown that it is possible to predict current and possible future distributions of vegetation with climate change using a vegetation model.
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Yield and quality of potatoes as affected by calcium nutrition, temperature and humidityModisane, Pulane Charity 02 October 2007 (has links)
Potato tubers are low in calcium due to limited calcium transport in the xylem and immobility of calcium in the phloem. Low tuber calcium content results in the occurrence of necrotic cells in the medullary tissues, which is a physiological disorder known as internal brown spot (IBS). A high incidence of IBS results in reduced tuber quality and market value. The objective of the study was to apply additional calcium to the potato crop using different calcium sources (gypsiferous mine water, gypsum and calcium rich water) to determine the impact on tuber yield and quality. Commercial field trials were conducted at Kleinkopje mine on the Mpumalanga Highveld from August 2001 to January 2002 and from September 2002 to January 2003. The response of the potato cultivar Up-to-date to irrigation with gypsiferous mine water as a calcium source was investigated. At Kleinkopje there was no control field (irrigated with normal water) for direct comparison. Another field trial was established at University of Pretoria Experimental Farm where gypsum at four levels was broadcast and incorporated prior to planting. Pot trials were conducted under controlled conditions because calcium uptake is not affected only by the amount of calcium applied or the location of the calcium application. Factors that affect calcium uptake such as temperature and humidity also play a role. Two pot experiments were conducted under controlled conditions from July to October 2002 and from October 2002 to January 2003. In these experiments, the effect of applying increasing calcium concentrations in calcium rich water at high (27/17oC) and low (22/14oC) controlled temperatures and humidities (35% and 85%) on tuber calcium content and quality were investigated. The parameters measured included growth analysis, leaf and tuber chemical analysis, tuber yield and quality. For the field trials soil sampling was done at the beginning and at the end of the cropping season for chemical analysis. Irrigation with gypsiferous mine water did not have a negative impact on overall potato growth. Higher levels of calcium (in irrigation water or gypsum) also did not have a negative effect on other nutrient levels. Irrigating potato plants with gypsiferous mine water resulted in high tuber yields of 52 t/ha in 2001 and 62 t/ha in 2002 seasons, which are good yields for Mpumalanga. Applying higher gypsum levels as a preplant broadcast resulted in high tuber yields (52 t/ha), which is a good yield for Hatfield. Application of gypsum as a preplant broadcast and irrigation with gypsiferous mine water resulted in good quality tubers (SG > 1.075 and chip colour > 45). This implies that gypsiferous mine water can possibly be used for irrigation of potatoes as a calcium source. The calcium nutrition of the potato tubers was not affected by the amount of calcium applied to the plants, calcium uptake or distribution within the plant only. Environmental conditions (temperature and humidity), which affect these functions also played a role. It has been discovered that lowering the temperature (22/14oC) and low humidity (35%) had beneficial effects on the tuber yield. Maintaining plants at low temperature (22/14oC) and high humidity (85%) could improve the tuber quality. However, high humidity (85%) and high temperature (27/17oC) improved calcium uptake by the tubers. / Dissertation (MSc (Agric) Agronomy)--University of Pretoria, 2007. / Plant Production and Soil Science / MSc (Agric) / unrestricted
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The effect of temperature and humidity on the resistance of mice to influenza virus infection /Rapoza, Norbert January 1960 (has links)
No description available.
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Development of a geochemical model to predict leachate water quality associated with coal mining practices / Karl Nicolaus van ZweelVan Zweel, Karl Nicolaus January 2015 (has links)
South Africa mines coal to supply in the growing energy demands of the country. A majority of these mines are opencast resulting in back filled pits and above ground disposal facilities. Leachate emanating from these disposal sites are saline and in most cases highly acidic. Currently the standard testing procedure to quantify expected leachate qualities include Acid Base Accounting (ABA), Net-acid Generating test (NAG), static-and kinetic leaching.
The aim of this study is to model standard humidity cell leach tests performed using the PHREEQC code. This model can then be scaled up to field conditions to model 1D reactive transport. It is commonly accepted that the rate of pyrite oxidation in backfilled pits and waste storage facilities is governed by the rate of oxygen ingress and that no pyrite oxidation take place in the saturated zone. This is not the case for humidity cells, as sufficient oxygen is available for reaction. Pyrite reactions rates in humidity cells is expected to be governed by a combination of available reaction surface and ash layer resistance. This is modelled in PHREEQC (Parkhurst & Appelo, 2003) using the KINETIC block. Leachate composition is then modelled in the column by making use of the TRANSPORT block. The experimental data is fitted by using the reactive surface and ash layer diffusion coefficient as a fitting parameter.
PHREEQC does not have a gas transport module to model oxygen diffusion through the column. Due to this shortfall of PHREEQC, the influence of oxygen ingress in the system can not be directly modelled under kinetic conditions. Davis and Ritchie (1986a) proposed an anlylitical solution in which the integrated sulphate production rate can be calculated for a waste heap dump. This rate takes into account the influence of oxygen ingress and the development of an ash layer resistance to the pyrite oxydation rate. This intergrated rate can then be defined in a RATES block in PHREEQC.
The Aproximate Analytical Solution (AAS) model proposed by Davis and Ritchie (1986a) is used to scale up the model used for the humidity leach cell experiment. It was found from the modelling results and comparison with PYROX that the model under predicts the integrated sulphate production rate in the initial stages of the reacting waste heap dump. It does however show results that are in close agreement
with the results obtained from PYROX in later stages of the lifespan of the waste
heap dump. This highlight limitations to the AAS model’s applicability on geochemical
problems. The model can only be applied to describe waste heap dumps where the
particles at the top of the heap are fully oxidized. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2015
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Development of a geochemical model to predict leachate water quality associated with coal mining practices / Karl Nicolaus van ZweelVan Zweel, Karl Nicolaus January 2015 (has links)
South Africa mines coal to supply in the growing energy demands of the country. A majority of these mines are opencast resulting in back filled pits and above ground disposal facilities. Leachate emanating from these disposal sites are saline and in most cases highly acidic. Currently the standard testing procedure to quantify expected leachate qualities include Acid Base Accounting (ABA), Net-acid Generating test (NAG), static-and kinetic leaching.
The aim of this study is to model standard humidity cell leach tests performed using the PHREEQC code. This model can then be scaled up to field conditions to model 1D reactive transport. It is commonly accepted that the rate of pyrite oxidation in backfilled pits and waste storage facilities is governed by the rate of oxygen ingress and that no pyrite oxidation take place in the saturated zone. This is not the case for humidity cells, as sufficient oxygen is available for reaction. Pyrite reactions rates in humidity cells is expected to be governed by a combination of available reaction surface and ash layer resistance. This is modelled in PHREEQC (Parkhurst & Appelo, 2003) using the KINETIC block. Leachate composition is then modelled in the column by making use of the TRANSPORT block. The experimental data is fitted by using the reactive surface and ash layer diffusion coefficient as a fitting parameter.
PHREEQC does not have a gas transport module to model oxygen diffusion through the column. Due to this shortfall of PHREEQC, the influence of oxygen ingress in the system can not be directly modelled under kinetic conditions. Davis and Ritchie (1986a) proposed an anlylitical solution in which the integrated sulphate production rate can be calculated for a waste heap dump. This rate takes into account the influence of oxygen ingress and the development of an ash layer resistance to the pyrite oxydation rate. This intergrated rate can then be defined in a RATES block in PHREEQC.
The Aproximate Analytical Solution (AAS) model proposed by Davis and Ritchie (1986a) is used to scale up the model used for the humidity leach cell experiment. It was found from the modelling results and comparison with PYROX that the model under predicts the integrated sulphate production rate in the initial stages of the reacting waste heap dump. It does however show results that are in close agreement
with the results obtained from PYROX in later stages of the lifespan of the waste
heap dump. This highlight limitations to the AAS model’s applicability on geochemical
problems. The model can only be applied to describe waste heap dumps where the
particles at the top of the heap are fully oxidized. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2015
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