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355 Uppsatser om Maximum a posteriori - Sida 9 av 24

Resultat från avkommeprövning av plusträd av vårtbjörk (Betula pendula)

Förädlingsarbetet på vårtbjörk (Betula pendula Roth) fick ett uppsving på slutet av 80-talet efter en ändrad opinion om björkens betydelse. En ny förädlingsplan togs fram med mål att förädla fram tidig höjdutveckling, högre torrsubstansproduktion och bättre virkeskvalitet. Syftet med denna studie är att undersöka möjliga förbättringar av vårtbjörk utifrån mätningar av ett försök med halvsyskonfamiljer. Detta genom beräkningar av heritabilitet, genetisk vinst, variationskoefficient och korrelationer för egenskaperna diameter, höjd, vitalitet, klykor, rakhet och grenstruktur, vid 10 och 21 års ålder. För den statiskista analysen användes en mixad linjär modell som kördes i programmet ASReml, vilket bygger på restricted maximum likelihood metoden. Resultatet visar att förädlingsmöjligheter för vårtbjörk är goda speciellt för höjd och diameter, genetisk vinst är skattad till 20 % respektive 25 %. Klykor, rakhet och grenstruktur, visade inte lika lovande resultat, genetisk vinst låg på 13 %, 7 % respektive 7 % vid år tio. Korrelationerna mellan egenskaperna tyder på svårigheter att förädla för både bättre tillväxt och kvalitet, till exempel diametern vid år 10 har en negativ korrelation med grenstrukturen vid år 21 på -0,681..

Accelererat åldrande av produkter Apelsinjuice och hallondryck

Brämhults Juice AB is one of Sweden?s leading producers of fresh fruit juices and drinks. The fruit drinks last 3 days once opened and when stored in a refrigerator kept at 7°C. Since factors that shorten the drinks? best before date are usually not noticed until the entire batch has expired, it would be advantageous to find a way to accelerate the drinks? natural deterioration, so that an unusal short best before date is noticed before more products are shipped off to the stores.

Utvärdering och implementering av automatiska farthållare i fordonssimulator

Vehicle simulators are becoming more common in vehicle industries. Company earns lot of money on simulations instead of real tests. Real tests are necessary but not made so extensively as before.In this thesis the building of an vehice simulator will be described and a comparison between three different cruise controls. The three cruise controls are PI-regulator, a regulator who regulates after positions in the terrain and a MPC-regulator. The reason for choosing this three is to see the difference between simple regulation and more complex regulation with respect to fuel consumption, travel time and complexity.The vehicle simulator is made in Matlab/Simulink, Visual Studio and Open Scene Graph.

Funktionsupphandling av solelanläggningar

This thesis aims to contribute to improved functional procurement of photovoltaic systems, PV systems. Functional procurement means that criteria concerning a function are set rather than specifying technical details or products. Possible advantages and difficulties in using functional procurement have been analyzed by interviews, simulations and a case study. Electricity production and surplus production for different scenarios have been simulated via MATLAB. The MATLAB script was also used to generate rules of thumb on feasible solar fraction for six different load profiles; a church, a farm, a car mechanic, an office, an industry and an apartment building.

Modellering och design av elmotor för mutterdragare

This thesis was carried out at Atlas Copco Tools and Assembly Systems. The purpose hasbeen to develop a design tool to be used for development of new electric motors for AtlasCopcos electric nutrunners. The focus of the thesis has been to increase productivity bydecreasing the power losses in an electric tool. The productivity is defined as themaximum number of tightenings a nutrunner can perform without becoming too hot.Before starting the development of this design tool an existing Matlab script, whichcalculates the losses in a slotless electric motor, has been studied and modified torepresent the real losses in a better way. The modification has been made by performingpractical studies of different losses and then adjusting existing parameters in the Matlabscript.Because design changes in one part of a mechatronic system can lead to a decrease inperformance of another part the choice of parameters that can be changed has been madeso that other parts of the system is affected as little as possible.A study of the existing tools efficiency during an entire tightening has been made toincrease the understanding of when and where the different losses appear and to comparethe modified Matlab script with the measured values.The design tool was formed so that it executes the Matlab script, that calculates thelosses, for a number of different design options and stores the alternative which producesthe least losses.

Design och framtagande av mätanordning för ström och effek på trefas ledare : Josi Periferi strömmeter

The assignment is issued by Scania Maintence AB seeking a new approach to detect power changes in their industrial processes. The work has taken place at Ångströmslaboratoriet and tests have been performed at Scania AB Södertälje.Today?s society consumes enormous amount of energy. In both economically and environmental view, it is important that the processes are effective, with high power factor. There are many ways to measure power in the industry, what they all have in common is that the installation is advanced, requires time and planning.

Lagring av kyla med horisontella markvärmeväxlare för kylning av koncepthus i Mellanöstern

Norconsult AB has developed a solarhousing concept, a house designed for the warm climate in the Middle East andwith large quantities of solar panels installed. The cooling system for the house was designed in an earlier report, the purpose of this thesis is to investigate the possibility of short and long term storage of thermal energy via an underground energy storage volume.Two different designs of the storage and three different filling materials have been integrated into a model to simulate different cases. The first design consisted of pipes installed in the ground, without insulation. The second design consisted of an insulated concrete box installed to prevent thermal energy from the surrounding soil to flow towards the lower temperature regions within the storage. The three different filling materials were dry saudi sand, water saturated saudi sand and the filling material used by the client for energy storage in Sweden.The results from the simulations show that neither of the designs, regardless of the filling material, managed to extract enough thermal energy from the house to the ground to uphold the demands of indoor climate.

Självförsörjande elgenerering : Kan Orust bli självförsörjande på förnybar el?

Orust Kretsloppsakademi is a nonprofit organisation, with a goal of annually generate the same amount of electrical energy that is consumed. Orust is an island on the west coast of Sweden, north of Gothenburg. The population of 15 000 reaches 40 000 during summer, due to the large amount of vacationer. The total electricity demand is 174 GWh a year with a maximum power need of 32 MW. This report presents an analysis for the plausibility of their plan and from a power system stability perspective, the effects on the electrical grid.The conclusion is that the restraints for development of power generation from wind, solar and wave generation, are the power systems capability to transfer power, primarily in the transformers of the grid.

En arbetsmiljöutredning för yrkeschaufförer hos Schenker Åkeri AB i Halmstad

The project has been done in cooperation with Schenker Åkeri AB in Sweden, Halmstad. Theproject is based on an inspection made by Arbetsmiljöverket, where they found minorshortcomings with distribution of goods for the employees. The project is an investigation ofthe drivers? working environment.Schenker Logistics is one of the world's leading providers of integrated logistics services.Schenker Åkeri AB is a subsidiary to Schenker Logistics and transports 2.4 million tons ofgoods yearly.The project started with a background study to evaluate drivers working environment. Wehave studied goods receptions, the working environment, strain injury and injury mechanisms.Methods used was observations, tests, questionnaire surveys and ergonomic andbiomechanical calculations.One result of the study is a working model, which gives recommendations for the maximumweight a driver should push and pull.

Jämförande av Genesis Single och kliniska test : Muskelstyrka hos individer med tidigare ACL-skada

Inom sjukgymnastiken används mätning av muskelstyrka för att utvärdera och planera rehabiliteringsperioder. Isokinetiska dynamometrar och one repetition maximum (1RM) är två vanliga metoder för att mäta muskelstyrka. Efter en skada på främre korsbandet (ACL) sker en muskelatrofi av bland annat mm. quadriceps och hamstringsmuskulaturen och det är därför viktigt att kunna utvärdera dessa muskler. Genesis Single är en ny tränings- och utvärderingsmaskin på vilken inga tidigare studier gjorts.

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.

Mobilt övervakningssystem : System för internetkommunikation mellan sensorer, webbsida, server och databas

This thesis has been carried out in cooperation with a company which develops mobile sensor platforms. The sensors measure different types of data such as temperature, pressure etc.. They will communicate through the internet with a server that stores data in a database. This system will be controlled and monitored through a web page. The project's aim has been to develop this system and to implement a server, a database, a website and a client application that simulates sensor signals.

Åsktransienter och överspänningar : En spänningsfylld simulering av elkraftsystemet vid Forsmark 3

A power system will inevitably be subjected to transient overvoltages, most often produced by switching operations and lightning strikes. These transient overvoltages may harm sensitive equipment without sufficient protection, but it is not an easy task to predict what transients may occur or how they affect the system. A fault occurred in a low voltage system at Forsmark 2012 and overvoltages from lightning were concluded as the probable cause. The three aims with this thesis are to develop and test a model of the power system at Forsmark 3, analyse the transient behaviour of the system when subjected to lightning surges and identify critical parameters, and lastly to provide a tool for investigating the protection of the system. The modelling and simulations were performed in the freely available simulation program LT Spice.

Biologiska behandlingsmetoder för rening av rejektvatten från biogasproduktion

In this literature review the characteristics of two free-floating macrophytes, water hyacinth   (Eichhornia crassipes) and duckweed (Lemna sp.), and two microalgae, Chlorella and Scenedesmus, have been examined regarding their suitability as efficient nutrient removers in the treatment of wastewater with high levels of nutrients and suspended solids from a biogas plant in Loudden. The needs required for the plants to be able to grow in wastewater and the amounts of biomass they can produce have also been studied. The results show that Chlorella is capable of a very high uptake of nutrients in photobioreactors with high nutrient loadings. With an ammonia uptake maximum value at 10900mg/m2/d Chlorella outshines the other organisms in this study. The test organism that performed the closest to Chlorella in terms of nitrogen uptake was water hyacinth with an uptake about 1602mg/m2/d.

Styrketillväxt med hjälp av vibrationsplatta

Abstract 1.The purpose of this study was to investigate the effects whole body vibrations on maximal strength, power output and neuromuscular activity in m. pectoralis major during bench press.Participants consisted of 35 male and 9 female military high school students (m=23, 1 years). On the basis of initial maximal performances in bench press the participants was divided into two experiments groups and one control group. Intervention groups performed a specifically designed push up program on a vibrating plate respectively a step board during 12 weeks Initial load at 60 % of 1 RM showed an average of 46, 5 kg. All groups showed an average increase of 13 kg for each person after 12 weeks.

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