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5243 Uppsatser om High-strength concrete - Sida 34 av 350
Optimering av sintrade kugghjul
Powder Metal (PM) gears are machine element components which operate under the same principle as conventional gears, but, due to their intrinsic material characteristic need to be designed slightly different, and its manufacturing process offers advantages previously unobtainable by conventional steel gear manufacturing methods. The use of PM in similar applications, such as synchronous hubs, makes them a suitable candidate for production in such material. The current master thesis work focuses on gear design using PM by utilizing finite element method (FEM) to reduce weight and inertia taking into account root bending strength and tooth deflection.First a topological optimization is used to determine feasible candidates for different web designs which have as objective to reduce volume, similar topologies were shown during different loading conditions; and hence, this topology was chosen as a suitable candidate. A shape optimization of the topological candidate was performed having as state variables root bending strength, independent for compressive and tensile side of the tooth loading; and tooth deflection, which in concept can be correlated to static transmission error (TE).Another aspect in this thesis analysed is the possibility to incorporate non-trochoid root geometry, a trochoid root is always present when machining with a hob, into the gear root and hence reduce the stress concentration here. Due to the use of PM, a non-symmetric optimized root can be achieved and hence be optimizing compression and tension.Results showed significantly lower inertia, for example certain results showed 40% reduced when compared to solid gear, with adverse effects as increase in tooth deformation and increase in maximum principal stress.
Faktorer som påverkar lönsamheten vid köp av skogsfastigheter i Norrbotten
During the past 20 years, the price of forest estates in Sweden has raised more than the price of timber. The purpose of this study is to investigate if it, despite this development, is possible to buy a forest estate based on economic grounds. Different forest parameters will also be studied to analyse their effect on the profitability.
The study is done in cooperation with the company LRF Konsult. Purchase price of 34 forest estates near the coast of Norrbotten, Sweden, has been compared to yield valuation. For the valuation, guidelines from the Swedish author Lantmäteriet was used.
Lantbruk i framtiden : ett praktikfall
The economic prerequisite to many farmers in Sweden after the EU membership and the
new agriculture policy has generated large demands on the farm management. Until year
2004 you got a grant based on what you had produced and not on consumer demand. In
2005 a new economic aid (Mid Term Revue) was introduced and the conditions has
changed again. Due to this I have chosen to do a cost-benefit analysis on a case, to
investigate if the present production is sustainable in the future.
My conclusion is that the profitability is acceptable even if the farm has a high debt. But
to make the production more profitable the products produced should be refined as much
as possible at the farm, to get maximum economic return.
Skyltfönster som kommunikationsverktyg- En kvantitativ studie om kreativa och mindre kreativa skyltfönsters effekter
This research examines the effects of creative store window displays of fashion brands in enhancing recall, attitudes, intentions and brand associations. A comparison has been made between high-end and low-end brands, creative versus non creative store window displays to identify differences in effects. The theory applied in this study has been used from creative advertising effects due to the lack of relevant research in store window display effects. Therefore this study is a contribution to the research of store window effects. The method used in this study compare fashion high-end brand with fashion low-end brand by placing the products in the store window display where the creativity has been manipulated.
Förberedelseklass eller direkt integrering? : En jämförande studie om hur två skolor i Södertälje kommun med olika arbetssätt arbetar med att integrera nyanlända högstadieelever i den svenska språkundervisningen
The aim of this essay is to examine how two different schools in Södertälje municipality are working to include and integrate newly arrived high school students in the subject Swedish as a second language. I will do a comparative study in which I study the teachers? completely opposite way of working to integrate newly arrived school students in the subject Swedish as a second language. I have used a qualitative method where I have conducted interviews. My main theory is Peder Haug's (1998) theory.
Effektiv lagerstyrning genom tillförlitlig prognostisering : Effective inventory control through reliable forecasting
This study was done regarding whether sealing or ventilation is the best solution to prevent moisture on cold attics. The authors of this report addressed the problem with moisture in attics when they started their cooperation with Peab.The methods included interviews with people, database research, and calculations of a project in Akersberga north of Stockholm. The conclusion is based on interviews and other information as they are analyzed in relation to the house of reference. The focus of this report is on problems with moisture in the attics known as cold attics.The background of the problem with moisture is that today?s slabs are usually insulated to save energy and that the attics nearly gives the climate as the outdoor climate.
Energibalans Dåva Kraftvärmeverk
To be able to measure high-surge voltages and transients with short rise times youneed measuring instruments with a high sampling frequency and large Bandwidth.These surges and transients occur primarily at lightning but can also occur at forexample at connecting errors at an electrical switch-gear. This report describes thework with finding two solutions for measuring and log data from these surges andtransients. One temporary solution where a measurement program has beendeveloped. A second solution where different company solutions have been analyzedto decide which fits best. For these measurement solutions two solutions for bringingdown the voltage has been used.
Stamskador i gallringsbestånd
This study was conducted on a property with a thinning machine team. The purpose was to investigate in which machine, the harvester or the forwarder, that caused most damage to the trees in six different stands. Different factors, related to the damage frequency in the stands, were checked out. For example: basal area per hectare, thinning strength, tree diameter and the rate of production.
The harvester drivers were also interviewed about how, when and why stem damages occur and how to minimize them.
The study stated that 4.3 percent of the trees were damaged. Out of these 88 percent was caused by the harvester and the rest, 12 percent, by the forwarder..
Nitrat i grundvattnet : Modellanalys av vattenflöde till Hörviks vattentäkt
A well, situated on Listerlandet in the western part of Blekinge in Sweden, has a very high content of nitrate. Water with a too high content of nitrate is hazardous to human health, in particular to small children. The area surrounding the well is mostly drained agricultural land with some larger farms for chicken and mink. The well takes its water from the bedrock and is deeper than most other wells affected by nitrate. The bedrock in the area is dominated by limestone with a relatively high flow of water.This thesis was performed in order to find the source of the nitrate.
Status i grupphierarkin : om barns sociala interaktioner
In this study the author attempts to identify factors that are determinants for why some pupils in Swedish grade school have high status in comparison with their peers. The study takes on the characteristics of both an ethnographic and a literature study by comparing the findings of interviews carried out with students of a first grade class with previous research. The study identify several tools for analyzing of how status may be understood in specific situations.The study also finds that important factors for gaining high status amongst children in aschool classes might be the ability to apply access strategies to get accepted in social interactions, such as game play, have the ability to create games that are enjoyed by peers and social skills, to name a few. Overall the study shows that children's game play with each otherare crucial for their social interactions and their social position. The study also show that children that have earlier established relationships with other children in a specific group alsohave a better opportunity to establish a high status position..
Svenska livsmedel - varför? : restaurangers, grossisters och offentlig upphandlares inställning till livsmedel från Sverige
The background of this research is that Swedish food products have hard to compete at the home market, depending on imported food products that increase more and more for every year that pass by. The ethic values LRF associate with Swedish food products, many customers have hard to put in relation with condition of foreign agriculture.
Most customers today inquire high quality, safety and convenience in the food which they are eating. The source of their food seems to have less meaning. Many restaurants and bigger households appreciate Swedish food products and wants to buy them but price differences against foreign wares are to high.
We have done oral interviews with wholesale dealers, restaurants, public purchasers and with different market organisations, there we have discussed buying strategies, the way they see the primary producer, the conscious of guests, choice and attitudes to Swedish and foreign products, distribution of power in the food market chain and to what position and suspension, they want the ranks of suppliers to have.
The result shows the share of imported wares within restaurants and bigger households are at a high level and will continuing increasing. Within these sectors the final consumer in many cases put less effort in the origin of the raw source of food.
Könsselektering av spermier från lantbrukets husdjur
Millions of preselected progeny have been born since the development of The Beltsville Sperm Sexing Technology 1986. The method is based on flow cytometry and sorting is done on the basis of DNA difference of the X- and Y-chromosomes. Preselection of progeny provides an opportunity to obtain genetic gain and increased production as well as increased animal welfare and decreased environmental impact. However, the method is associated with low fertility, high costs and uncertainty whether the sorting process contributes to DNA damage and thereby results in genetically impaired progeny. Today, sex sorted sperm is only commercially available in the bovine industry, due to the fact that bull sperm is more suitable for selection than sperm from other species.
Högt hus i Chongqing/Kina - ett bostadsprojekt
This is a project showing a proposal on how a high-rise building gains qualities similar to middle rise houses of 7-9 stories. The closed, isolated and often anonymous life in the high building opens up through gardens. The resident meet the outdoor environment on the balcony, or has direct access to a garden.Instead of moving in a closed core, the resident will meet the climate and outdoor conditions as soon as he or she leaves the apartment.The project consists of two parts, where the first is presenting a building proposal, the second is expanding the knowledge through background research. The topics are history concerning the skyscraper and the skyscraper globally, closing up with the situation in China..
Mät och loggningsutrustning för spänningstransienter.
To be able to measure high-surge voltages and transients with short rise times youneed measuring instruments with a high sampling frequency and large Bandwidth.These surges and transients occur primarily at lightning but can also occur at forexample at connecting errors at an electrical switch-gear. This report describes thework with finding two solutions for measuring and log data from these surges andtransients. One temporary solution where a measurement program has beendeveloped. A second solution where different company solutions have been analyzedto decide which fits best. For these measurement solutions two solutions for bringingdown the voltage has been used.
IKT i mellanstadiet : En kvalitativ studie av skolledares syn på sin roll i integrering av IKT i undervisningen
The overall purpose of this essay is to come to a deeper understanding about videos in the Youtube beauty community by using a mixture of qualitative and quantitative methods. By answering the main questions of the essay which are; What quantitatively measurable components are there in the videos that can be seen as contributing factors leading to the fact that some generate more views that others?; Is there a set mold for success containing certain aspects that a video must have to stand out?; What correlations can be found between the two categories of analysis and how do these potential correlations affect the popularity of the video? and What effects do specific components on the level of popularity of the video?, we?ve been able to distinguish differences as well as similarities on both qualitative and quantitative levels. We have also seen that using the two methods together have enabled us to reach more profound results. The main result that we have found on a quantitative level is that there are obvious correlations between a high level of popularity and a good visual quality.