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946 Uppsatser om Concrete composition - Sida 49 av 64

Foderbetor och kogödsel som substrat för biogasproduktion; anaerob mesofil samrötning i labbskala

One of Sweden?s sixteen national environmental objectives strives to decrease the impact on the climate. By 2020, green house gas emissions should be 40 % less compared to the levels of 1990 and a minimum of 50 % of the energy consumption should come from renewable energy sources. Because of this there is a great need of increasing the production of renewable energy. This is where biogas comes in as a competitive alternative.

Utveckling av en HBV/PULS-model med sammanfogade markfuktighets- och responsrutiner

Soil properties affect the chemical composition of soil water. When studying transport of chemical substances through a basin, it is therefore important to know from which soil layer the main part of the runoff is generated. The aim of this study is to develop an HBV/PULSE model with merged soil moisture and response routines, which generates good approximations of groundwater levels. It should be possible to extend the model to simulate transport of substances and take into account which soil layer the groundwater level is currently in. The hydrological version of HBV/PULSE is used since there is no need to account for pH or alcalinity at this stage.

Framtidens stadsträd för en fungerande grönstruktur

The effect of climate change places demands on how we build cities. Cities have to be built denser to meet the objectives of sustainability but as a result of this densification city green areas are at risk of exploitationand disappearing. The question this raises is whether there has to be an opposition between a dense and a green city?Urban trees are playing a very important role in cities. They stand as the major part of the vegetation in citieswhich are otherwise dominated with concrete and stone.

Blivande folkskollärare : En social rekryteringsstudie av inskrivna män vid Karlstads folkskollärarseminarium

The main purpose of this essay is to interpret possible pattern in social extraction, among future male elementary school teachers, at Karlstads elementary school teachers seminar over time. The questions that intend to concrete the purpose, and describe the possible pattern of social backgrounds are following; Where do the future male elementary school teachers come from? How the social recrutiment is divided in professional categorys, and is there any distinction in the pattern of social recrutiment over time? Which social groups were represented at Karlstads elementary school teachers seminar between the year of 1860-1940, and how they were divided.At the categorization of occupation, class- and social belongings I´ve used Sten Carlssons theory of professional categories (the social transformation in Sweden after 1866) which also was used by Kerstin Skog-Östlin in her dissertation Pedagogical control and authortity.The changes in the pattern of social recruitment of male future elementary school teachers were following; the proportion of students with agricultural backgrounds has decreased between the year of 1860 and the turn of the century. Further there was a substantial reduction of students with agricultural backgrounds between the turn of the century and the year of 1940. Students with agricultural backgrounds had the lowest represented frequency according to the investigation.

Tilläggsisolering - lönsamt enligt en livscykelkostnadsmodell?

It is found that the properties of the record years of 1965-1975 is leaking a lot of energy andthese properties are facing a major energy efficiency. From the energy aspect, the facade isafflicted with poor thermal insulation which is a big problem. To address this problem addinginsulation is a good alternative to reduce overall energy consumption of a building. Thewindows on these buildings are also a problem from the energy point of view. Therefore,there are many reasons considered for energy upgrading.

Utvärdering av val av hållfastetsklass

SammanfattningBetong delas in i en rad olika hållfasthetsklasser som påverkar vilka egenskaper betongen har vad gäller hållfastheten, högre klass ger högre hållfasthet. Vid dimensionering av betongkonstruktioner kommer valet av hållfasthetsklass på betongen spela in på hur stor armeringsmängd som fordras. I hur stor grad armeringsmängden påverkas beror på vilken typ av element det gäller samt vilka typer av laster det påverkas av, men generellt gäller att en högre hållfasthetsklass på betongen genererar en lägre armeringsmängd. Tryckta konstruktioner, exempelvis väggar, pelare och valv, i betong klarar stora laster i sig utan kraftig armering. Denna studie har haft som mål att ta fram ett dokument som påvisar i vilka typer av element det lönar sig ekonomiskt att använda en högre hållfasthetsklass med en lägre armeringsmängd som påföljd, samt redovisa priset för respektive tvärsnitt. Den fiktiva byggnad som studerats är ett 15 våningars bostadshus uppfört i Östersund.

Biodiversitet av evertebrater på vegetativa tak

In a city sometimes conflicts arise between either to save the species-rich vacant lots where many species thrive, or to build new buildings. Green roofs can then serve as a refuge for plants and animals that have had their natural habitat destroyed or diminished. Today we know too little about green roofs contribution to the biodiversity in the cities. We also know very little about how various types of vegetation on roof can increase biodiversity and its ability to attract different species.The aim with this study was to examine how different types of vegetation on the roofs affect the biodiversity of the invertebrate and how species-composition and number of individuals differ between the roof- and groundlevel.This study has been carried out on Augustenborg Botanical Roof Gardens in Malmo, and in an area about 1.5 kilometers away from Augustenborg. Three different types of vegetation on the roof and ground floor were selected: sedum- ruderal and grass.

Det energisnåla isoleringsmaterialet

This bachelor essay is divided into two parts, the first being a construction of a single-familyhouse and the second an in-depth study of five different isolation materials, analysed from anenergy perspective.The first part, the construction of the single-family house, has been created from knowledgeacquired during three years of studying at KTH Royal institute of Technology in Stockholm, inthe program Architecture and the Built Environment. The constructed house is a one-floorhouse of 137m2with façade plaster, situated in Borlänge, Sweden. The house has a wooden framewhich is built on a on sight cast concrete foundation, on the ground. The house?s roof is a gableroof, which has an angle of 24 degrees.

Effect of botanically diverse pastures on the milk fatty acid profiles in New Zealand dairy cows

Botanically diverse pastures are commonly used in New Zealand to reduce the ruminant environmental impact by reducing the methane production from the rumen digestion. In order to evaluate the effects diverse pasture species have on the milk fatty acid profile seventy-two lactating Friesian-Jersey crossbred dairy cows were used in a randomised block design with two replicates of six treatments. Six different pasture mixtures were fed at a daily allowance of approximately 15 kg DM/cow/day. The mixtures were categorised as either a simple or a diverse pasture. The simple mixtures all contained white clover with the addition of either a standard diploid perennial ryegrass (RG), a diploid high sugar ryegrass (HS) or tall fescue (TF).

En validitetsstudie på beeptestet : avseende maximal aerob kapacitet för elitishockeyspelare

Introduction: This study aimed to investigate the validity and reliability of the 20m multistage shuttle run test (MST) for elite ice hockey players as a predictor of the maximal aerobic capacity and the how the result is affected by the players age, aerobic and anaerobic capacity, body composition and test surface. The purpose of this was to find out the potential of the 20-m shuttle run test as a measuringtool for the maximal aerobic capacity in frequent testing periods during the season. It is very interesting to be able to administer this easily because the competative phase of the season is very long compared to the pre-seasonal phase and earlier studies have shown that the aerobic capacity is being lowered during this competative phase of the season for elite icehockey players.Methods: 34 elite ice hockey players participated in this study (20.0±3.6 yrs, BMI 24.2±1.6 and VO2-max 58.0±4.8 ml O2?kg-1?min-1). During 3-5 days they underwent 2 MST tests (wood and rubber surface), treadmill running with VO2-max assessed with open-circuit technique, Wingate10% and FFM-assessment with underwater-technique.

AB Volvo Pentas emballagesystem - processen och förpackningslogistisk betydelse

Title AB Volvo Pentas packaging system ?process and packaging logisticsAuthor Peter Powell, Lund's Technical CollegeSupervisors Annika Olsson, Lund's Technical CollegeJan Svensson, AB Volvo PentaProblem - Packaging requirements ? Which requirements are there, how do they affect each other and how are they fulfilled?- Packaging process ? what is the line of action when developing new packaging and making adjustments in existing ones? Who has the responsibility to do what?- Packaging logistics ? How is the packaging system adapted to transport efficiency and handling?Objective To create an overall picture over how the packaging system affects and is affected by different functions and players within and beyond the company boundaries, to give a clear picture of how changes in the packaging system is made today and how it could work and finally to give suggestions for cost savings affected by the packaging system.Method The methods used for this thesis has mainly consisted of action research and at some extent case studies. As a previous employee at the department of logistics at Volvo Penta I?ve taken part of the environment, information and prerequisites that this thesis discusses on a daily basis. Case studies have been used for the collection and analysis of data concerning packaging logistics as I?ve chosen to consider only specific markets and packaging.Conclusions This thesis has highlighted the demands that are placed upon engine packaging throughout all concerned units and how these demands affect each other, positively and negatively.

Bullertunneln : En utredning kring en ny bullerlösning vid trafikleder

The purpose of this Master Thesis has been to investigate the possibilities for a new type of noise reduction solution that could decrease the negative effects resulting from larger traffic roads. The idea has been to construct a noise barrier with a roof ? like a tunnel placed on a road. The choice of material has been focused on transparent materials in order to lower visual intrusion and barrier effects. This project idea is called the Noise tunnel.After having investigated the current offer of noise solutions, it has been concluded that these solutions rarely provide a sufficient level of noise reduction ? at least not when government regulations of acceptable noise levels are applied.

Kvalitetssäkring av material och tjänster inom byggentreprenadbranschen

Quality is the key to a well executed product or service. The construction industry hasn?t highlighted the quality in recent times which have contributed to the construction industry receiving much criticism in the field. The public sees it as an offhanded industry where errors and delays are common.The reason for this is considered to be primarily the lack of time, constant pressure to reduce costs and skills and the ability to communicate between the parties about what the correct quality really means. The industry has begun to realize that it must start setting clearer standards and that there are great opportunities for improvement.This report will give Peab an opportunity to develop their quality work.

Turism i filmens värld : En fallstudie rörande tv-serien "Morden i Midsomers" potential som turismprodukt

This essay notice film and TV-series as a resource, which can be utililized by the tourism industry. To be more concrete, the aim of this essay is to examine if and how the Television series ?Midsomer murders? can be utilized as a tourism product. To fulfill the purpose of this essay, two different methods have been used: the study off literature and a content analyses, the later in form of a picture & film analyses. The results of this study showed that ?Midsomer murders? have qualifications enough to be a successful tourism product.

Potentiella armeringsfel inom byggproduktionen : En generell studie

Reinforcement is of great importance to fulfill the dimensioned strength of a concrete construction. This requires that the work needs to be carried out with adequate results that neither endangers the workers or the safety of the construction. Progressive development of the planning phase, construction documents, and construction methods is in constant need since the technology constantly evolves.In order for contractors to be able to get acceptances from their quotations requires that they have to increase their working pace in order to be able to leave a quotation with a lower price than the competition.Due to the increasing pace the different parts involved in the construction process is subjected to time pressure. The design stage, construction documents, work preparation and the execution are all affected when everything has to be finished quickly. To avoid problems, it is required that all parts are able to deliver good quality solutions and results under the influences of time pressure, which is not always easy.

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