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1720 Uppsatser om Heat treated wood - Sida 52 av 115

Biobränsleanvändning och Flameless oxidation i degelugnar för glassmältning

Idag värms glasugnar upp med antingen gasol eller olja, detta projekt vill visa på möjligheten att istället använda gas från biobränsleförgasning som förbränns utan synliga flammor. Detta skulle miljömässigt ge fördelarna att biobränslen inte bidrar till växthuseffekten och ge förutsättningar för att minska kväveoxidutsläppen genom bättre teknik än dagens.För att visa att det är möjligt att både behålla produktionen och reducera kväveoxiderna med förgasningsgas konstruerades en modell av ugnen och strömningsbilden studerades i vattenmodell. För att undersöka värmeöverföringen i ugnen behöver en eller flera kalorimetrar konstrueras för att kunna användas vid varma försök. Dimensionsberäkningar gjordes som visade att detta är möjligt med vissa typer av kalorimetrar..

Göteborgs konstmuseibibliotek : En skildring av bibliotekets historia till och med 1939

The subject of this thesis is the history of the library at The Göteborg Museum of Art. The aim of the thesis is to depict and analyze the emergence and the expansion of the library?s holdings until 1939. To fulfill the aim, two questions are asked. The first question is: Is it possible to argue that the library?s holdings were collected to document the entire world of art? The question is formulated in relation to a comment by Susan Wyngaard.

Vinster med björkinblandning i granbestånd i syfte att höja markens pH-värde

The soil acidification and the pH-value of the soil have been discussed for many years. Many observations of the tree species effects on the soil pH have been done. We have discussed the effects on the soil surface pH-value with a birch (Betula spp. L.) admixture in Norway spruce stands (Picea abies L.).We have used data from the Swedish National Forest Inventory. We have also discussed how the wood production and the biodiversity can be increased in mixed stands, in according to the Swedish forestry act Skogsvårdslagen. Our sampling areas are located in Norrland, Sweden. The results show a significant correlation between an increased birch admixture and an increased pH-value of the soil.

Jämförelse mellan olika material i spåröverbyggnadens bärlagerbärighets- och materialprovning av spårväg i Göteborg

This report is a study in voltagelevel in connection with regeneration of brake energy from the tramtype M31 in Gothenburg.In the act of braking, the tram M31 uses electrical braking where the electrical motors generates energy and if possible send it back to the overheadline, where other trams in the nearby can use this regenerated energy for its own driving force. In cases where no other energyconsumers are located in the same section, there is a resistance witch task is to convert this energy into heat. The regulation of this resistance appears to cause an increase in the voltagelevel into far too high levels.Investigations of the trams regulationequipment and its construction have been done. Further have measurements on the overheadline been performed in order to map the voltagevariations during a longer period of time.The result have been showing that the voltagelevel during regeneration often is as high as 880V-920V, more extreme values have not been observed in a large scale. The values are especially high compared to the nominal voltagelevel.

Fukthaltsförändringar för skogsbränsle : En jämförelse av torkförloppet i grönrisskotade och brunrisskotade vältor

In 1994 a new Forestry Act was accepted in Sweden. One of the aims of the law is to raise consideration forpreservation of biodiversity. Since the new law got accepted and some time has passed, there now lie someinterest in examining whether the law has been effective towards its purpose. Methods suitable for analysishave been examined during this study. The content of this pilot study is based around five parameters whichcan be used to validate the effects of the new law.

Passivhus det långsiktiga valet. En konkret jämförelse mellan konventionellt byggande och passivhus

This report is a study in voltagelevel in connection with regeneration of brake energy from the tramtype M31 in Gothenburg.In the act of braking, the tram M31 uses electrical braking where the electrical motors generates energy and if possible send it back to the overheadline, where other trams in the nearby can use this regenerated energy for its own driving force. In cases where no other energyconsumers are located in the same section, there is a resistance witch task is to convert this energy into heat. The regulation of this resistance appears to cause an increase in the voltagelevel into far too high levels.Investigations of the trams regulationequipment and its construction have been done. Further have measurements on the overheadline been performed in order to map the voltagevariations during a longer period of time.The result have been showing that the voltagelevel during regeneration often is as high as 880V-920V, more extreme values have not been observed in a large scale. The values are especially high compared to the nominal voltagelevel.

Incitament för förbättrat miljöarbete. En studie av miljöarbete I relationen mellan beställare och entreprenör

This report is a study in voltagelevel in connection with regeneration of brake energy from the tramtype M31 in Gothenburg.In the act of braking, the tram M31 uses electrical braking where the electrical motors generates energy and if possible send it back to the overheadline, where other trams in the nearby can use this regenerated energy for its own driving force. In cases where no other energyconsumers are located in the same section, there is a resistance witch task is to convert this energy into heat. The regulation of this resistance appears to cause an increase in the voltagelevel into far too high levels.Investigations of the trams regulationequipment and its construction have been done. Further have measurements on the overheadline been performed in order to map the voltagevariations during a longer period of time.The result have been showing that the voltagelevel during regeneration often is as high as 880V-920V, more extreme values have not been observed in a large scale. The values are especially high compared to the nominal voltagelevel.

Hiv/Aids : Vad rör det mig ?

Over 40 miljon people in the world suffer from hiv/aids today. Africa is the continent that is worst affected by hiv/aids but how is the situation in Sweden? Why is it so quiet concerning hiv/aids in Sweden? Our aim with this work was to find out about the hiv/aids situation in Sweden and particulary in Malmö. The result of our research was that hiv/aids have increased since the year 2000 and most of the people had caught the infection in other countries than Sweden. This raised our curiosity concerning how immigrants/refugees are being treated when they arrive in Malmö and what are being done to stop hiv/aids from spreading further.We became very disappointed when we realised how little that is actually being done and how poorly the collaboration between the institutions are working.

IKT - 2000-talets mentor? : En jämförande studie mellan manliga och kvinnliga pedagogers uppfattning om IKT i undervisningen

During the past decade Information Technology (IT) and Information and Communication Technology (ICT) have become the main tools in teaching. Authors and early educators who are treated in the study talks about how technology has come to change the school's approach to teaching and didactic tools. The technology has also affected students´ and teachers´ ways to work because the technology's versatility makes demands on the user's expertise and competence. The technical skills have long been associated as a male domain, where men are expected to master the technology´s versatility. These expectations are not the same for women.

Vårdtagarens perspektiv på sjuksköterskans bemötande

Every day in medical care the nurse and the patient meet, they are not just represented as the care giver and the care taker, but also as two unique individuals. The meeting is a very important part in caring and few studies have been made on this topic from the patient.s perspective. The purpose of this study was to describe the patient.s perspective on the meeting with the nurse. The study is a literature review, where articles have been reviewed, encoded, and then categorized. The result builds on our four main categories, confirmed as a unique indidual, the meaning of the information according to the patient, the humanistic side of the nurse, and the importance of humor in the meeting.

Ljud i landskapsarkitektur : från buller till kvalitet

Landscape architects has many ways of transforming our cities and landscapes. Traditionally, most attention has been put to visual qualities. Pen and paper are well established as the way to present proposals and to analyse in the landscape architects profession and training. But are we perhaps missing out on other ways of seeing the landscape? The purpose of this paper is to present sound as a tool of transformation. Sound in public spaces has long been treated just as noise and therefore unwanted.

Direkta effekter av insekticiden deltametrin på zooplankton och bottenfauna : en fältstudie av bieffekter av insekticidinducerad eliminering av signalkräfta på Gotland

Direct effects of the insecticide deltamethrin on zooplankton and benthic invertebrates werestudied during an attempt to eradicate signal crayfish. In accordance with earlier studies theresults of this investigation showed that deltamethrin is highly toxic for arthropods, whileRotifera, Oligochaeta and Mollusca have a higher tolerance. This study concludes thatRotifera in treated ponds coped with the actual concentration of deltamethrin used during theeradication attempt but that they probably got a different abundance and changed compositiondue to a new situation in competition and predation. Crustacean zooplankton totallydisappeared, but approximately a month after the treatment they began to recolonise. All thetaxonomical groups of arthropods drastically decreased in abundance, with total eliminationof the most sensitive groups.

Adaptiv temperaturreglering av bostadshus

The control of indoor temperature must be able to handle large time constants and both measureable disturbances like outdoor temperature, and non-measurable disturbances, like waste heat from appliances. Due to cheaper microcontrollers (small computers with designated tasks) with better performance, more advanced and computation-demanding methods for control can be used.In this thesis, Generalized Predictive Control (GPC) has been implemented and tested on a theoretically derived model of a house. GPC states that a model of the system is estimated in every sample, and the control is carried out simultaneously, based on predictions of the model. Disturbances like solar radiation can be estimated and used in the control as well. The control signals are determined by quadratic programming, which makes it possible to consider conditions, for example limitations on the control signals.GPC requires a number of parameters to be defined, like model order and control signal penalty, but is relatively robust for variations in them.

EU som Demokratifrämjare i Kroatien

The aim of this essay was to study the European Union?s (EU) role as a democracy promoter and its impact on Croatia?s democratization process. Croatia is a candidate country for membership in the EU which creates a possibility for impact and democracy promotion. The aim is met by studying the following questions:  In what way has the EU promoted democracy in Croatia? How did Croatia respond? To what extent has the EU contributed to Croatia?s democratization process?  Croatia is treated as a case study of the EU?s democracy promotion and the method used was qualitative text-analysis.

CFD simulering av kallras : Undersökning av temperatur- och luftbeteende intill höga glasfasader och i vistelsezon med golvvärme som en värmekälla

Glass has sophisticated front properties and are used as facades in high buildings. During cold periods, these glass facades could cause thermal discomfort, due to cold downdraught. Cold downdraught can be countered by placing heaters under glass surfaces. Nowadays technology offers highly insulating windows, which is why there is an interest to investigate the indoor climate with only underfloor heating. The research in this area is limited, and few empirical methods are available.

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