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4011 Uppsatser om Problems involving moisture - Sida 2 av 268

Fukt i byggnadsmaterial : Hur man förebygger fuktskador vid materialhantering på byggarbetsplatsen

Byggsektorn har fortfarande svårigheter med att hantera fuktproblematiken.  Vi har valt att fokusera på hanteringen av material i produktion. Den informationssamling vi utfört ligger till grund för vår analys och slutsats. Vi har intervjuat flera olika entreprenörer från byggbranschen för att ge oss en helhetssyn av fuktsäkerheten ute på byggarbetsplatserna. Studien påvisar att det råder brister både på beställar- och entreprenörssidan. Vi ser att det finns potential för förbättring när det så krävs.

Fukthalt i GROT - påverkande faktorer :

This study was carried out at the request of the bio energy company Naturbränsle. The company handles annually 750 000 m3 of chips from logging residues from a large area, from Östergötland in the south to Härjedalen in the north. In that area, about 50 bio fuel plants are customers. When Naturbränsle deliver chips from logging residues to their customers, the moisture content varies from 30 % to 60 %. The aim of the study was to sort out the affecting factors on the moisture content in the chips during handling and storage processes.

Utfackningsväggar ur lufttäthets- och fuktsäkerhetsperspektiv : En jämförelse mellan platsbyggda och prefabriceradeutfackningsväggar

The swedish national board of housing, Building and Planning,recommends that all stakeholders in the construction industryperform a moisture control design to make sure that the buildingachieves good moisture resistance. Since June 1, 2006 there are nospecific requirements or quantitative values for air leakage.Although the swedish national board of housing does presentrequirement that the building envelope must be sealed so that theclient?s requirements for specific energy consumption and installedelectric power for heating purposes are met. Despite this, studiesfrom SP shows that few buildings meet the client?s requirements inspecific energy, which increases the risk of occurrence ofcondensation-related moisture damage.This study aims to evaluate curtain walls connections from airsecurity and moisture safety.

Tilla?ggsisolering och fuktproblem i grundkonstruktionen platta pa? mark : En fallstudie i flerbostadshus inom stadsdelen Sa?tra i Ga?vle

Between 1965 and 1974, the Swedish Parliament decided to build one million dwellings, called Million Program. The million program buildings were erected with new, untried design solutions, in a short range of time, and at low cost. The residential buildings from that time are now greatly in need of renovation. The municipal housing company, Gavlega?rdarna, renovates and improves the energy efficiency at some of it?s apartment buildings in the district Sa?tra, Ga?vle.

Återfjädring vid bockning av höghållfast stål

Svenska Aerogel AB has developed the material Quartzene® which is of the typeprecipitated silica and contains calcium - magnesium silicate ((Ca, Mg) SiO3). Thematerial is used for molecular filtration of contaminated air. Qartzene?, which is inpellet form, is porous and has a high internal surface which is a requirement for themolecular filtration. With the use of various impregnations, filtration can affect thedesired outcome.

Biomass losses during short-term storage of bark and recovered wood

Storage of biomass is associated with problems like heat development, biomasslosses, and reduction of the fuel quality. Certain processes such as biological- andchemical degradation are responsible for these storage problems. This master?sthesis was carried out at Vattenfall Research and Development AB and is alignedtowards quantifying the biomass losses from short-term storage (1-2 months) ofbark and recovered wood. The biomass was stored in outdoor piles during differentseasons, campaign 1 (summer) and campaign 2 (autumn).

Fuktegenskaper hos Quartzene impregnerat med salter

Svenska Aerogel AB has developed the material Quartzene® which is of the typeprecipitated silica and contains calcium - magnesium silicate ((Ca, Mg) SiO3). Thematerial is used for molecular filtration of contaminated air. Qartzene?, which is inpellet form, is porous and has a high internal surface which is a requirement for themolecular filtration. With the use of various impregnations, filtration can affect thedesired outcome.

Problem i högt fuktbelastade byggnader : Riskbedömning med hjälp av WUFI

Många av Sveriges badhus byggda i slutet av 1900-talet börjar idag visa tecken på kraftiga fuktskador på grund av extrema inomhusklimat. Denna rapport förklarar den allmänna problematiken kring högt fuktbelastade byggnader och berör det fuktskadade badhuset Aquarena i Katrineholm.  Extrem noggrannhet krävs vid montering av ångspärr i en konstruktion, speciellt vid högt invändigt fukttillskott. Optimal placering av fuktspärren i konstruktionens varmare del innebär att fukt aldrig tillåts kondensera och därmed minimeras risken för fuktskador och negativa konsekvenser. Verkligheten visar också att om kunskaper om fukt och fuktskador prioriteras redan i ett tidigt stadium under projektering kan många hundratusentals kronor sparas. Beräkningar av fukttransport har gjorts för tidigare ytterväggskonstruktion i Aquarena (den som drabbats av skador) och nybyggd ytterväggskonstruktion (nyframtagen till återuppbyggnaden) i datorprogrammet WUFI Pro 4.2 och analyserats i WUFI Bio 3.0.

EAS-tagg med fuktsensor : Design och utvärdering av EAS-alarmteknologi för fuktdetektering

Electronic article surveillance (EAS) is widely used in shops and libraries together with an RF-tag attached to the goods or books in order to prevent shoplifting. By implementing the addition of a moisture sensor to the RF-tag, other functions become possible, including the ability to use as an alarm with regards to frozen goods, which have been shipped but which have melted and have, subsequently, refrozen. In- relation to care for the elderly, one time-consuming step involves checking whether there is the necessity for a change of diaper and this can, instead, be based on an RF-tag with an EAS-system alarm. A preliminary investigation was made using the moisture sensors, which involved how the resistance changes when liquid and/or heat is applied. A simulation of the LCCR circuit (RF-tag with the sensor) was conducted in order to determine how the resonance frequency changes for different resistances levels.

Droppbevattningens inverkan på kvalitet och kvantitet hos Solanum tuberosum L i jämförelse med konventionell spridarebevattning :

A literature study and a field trial have been carried out in order to investigate the physiological response of potato plants to different soil moisture levels. Higher yield, quality and number of tubers can according to the literature be obtained if constant high soil moisture is kept during major parts of the growing season. A field trial was set up where drip irrigation was used as an alternative to conventional irrigation techniques to maintain high and constant soil moisture. The application of water in the drip irrigated area was monitored and adjusted on a daily basis so that the soil moisture stayed as close as possible to the recommended level. The sprinkle irrigated area was irrigated according to traditional practices with approximately 35 mm every 7th to 10th day depending on the whether.

Elementkoncentrationer i gran utmed en markfuktighetsgradient :

One key factor in silviculture today is sustainability. In order to achieve sustainability it may be important to restore lost nutrients to the forest after clearcutting. In order to calculate the removal, you need to know how much of different elements you will find in different tree compartments. The aim of this study was to investigate if the concentration of elements in different tree compartments of spruce (Picea abies (L.) Karst) were related to the moisture conditions of the site. Five plots at Risfallet (60º 21´ N, 16º 13´ E), was placed along a moisture gradient in a 40- year spruce stand.

Elektrisk skorstenständare

Between 1965 and 1974, the Swedish Parliament decided to build one million dwellings, called Million Program. The million program buildings were erected with new, untried design solutions, in a short range of time, and at low cost. The residential buildings from that time are now greatly in need of renovation. The municipal housing company, Gavlega?rdarna, renovates and improves the energy efficiency at some of it?s apartment buildings in the district Sa?tra, Ga?vle.

Fuktskydd och planering i byggprojekt ? Erfarenheter från Eolshäll

When the Eolshällproject was completed for the first time, a great deal of moisturedamage was discovered. Therefore the structure completion was removed andreinstalled. The project was originally planned to cost a total of 126 million SEK, but thefinal costs landed on 271 million SEK. What caused this failure? Were the designs poor,was the technology used too advanced, or was the project not managed properly?Based on the Eolshällproject, theses will be presented about what may have caused themoisture damage.

Upprättande av mall för fuktsäkerhetsbeskrivning : Genom granskning av projekt ur fuktsäkerhetssynpunkt

During the 1990?s a large number of building projects were revealed where lack of moistsafety precautions during the construction process had led to extensive moisture damage. Alsoresent implemented studies have shown that the problems with moisture damages have ratherincreased than decreased during the past few years. Moist is considered to be one of the mainfactors to cause unhealth due to deficiencies in the indoor-environment and does also causeunnecessary expenses and a reduction of the confidence in the construction industry.In this Bachelor of Science thesis three projects have been reviewed to examine how moistsafetyhas been observed during the construction process. Main focus has been to identify thebuilding components that are the most exposed to moist, and to examine how they have beentaken into account during the period of design and construction.

Automatisering av spraytorkningsprocess

ABB Surge Arrestors in Ludvika have for a long time had a problem to keep the moisture at a steady state in the production of their ZnO-powder, that is used to produce varistors.Some black-box models of the spray drying process have been designed and evaluated to find a solution for the problem. After evaluating the collected data it has been found that variations in the supply voltage causes control difficulties for the operator. A cascade control system was designed, consisting of three PI control loops designed with lambda tuning. The disturbance in the supply voltagewas used as a feed forward in the control system.At the end of the project the control system was installed, and tests were made to verify the functionality of the regulator. It was shown that most of the variations in the moisture of the powder could be eliminated using small resources, through purchase of a process controller and four power meters.

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