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3466 Uppsatser om Production flow - Sida 52 av 232
Trafikverkets effektstyrningssystem - EFS 132 kV : Bidraget till minskade förluster
The technological legacy from the early electrification of the Swedish railroads has resulted in a power grid with a lower grid frequency than the national power grid from which it is fed. Energy transfer between these power grids with different frequencies requires substations, adapting the grid frequency for the rail road power grid. For this purpose, a feeding power grid has been built, stretching across the country from Boden in the north to Tälle/Häggvik in the south.Power transfer in the Swedish power grid results in voltage angle differences which increase with increasing loads and transfer distance. These voltage angle differences are transferred from the power feeding substations to the rail road power grid, will in some extent cause loss of energy due to unwanted power flows from north to south.To minimize the losses due to this phenomenon, a power management system called EFS 132 kV has been developed and implemented. The system minimizes the unwanted power flows and controls the desired power flow for a good distribution of loads between the power feeding substations.This thesis investigates the extent of the transmission losses avoided due to the EFS 132 kV that coordinates the idling angles to a common reference point.The results indicate that EFS 132 kV affects the power flow, especially between the northern substations through an improved load distribution.
Från gles skog och brokiga ungskogar till homogen produktionsskog : en skogshistorisk studie av Hällforsmarken under 1900-talet
The forest in the northern part of Sweden has changed dramatically during the last centuries. The forest has gone through a large-scale transformation, from it being only used locally for domestic purposes to becoming very important raw material for Sweden in the industrial age. The strategy by foresters during the second half of the 20th century has been to create pure production forests for commercial forestry. This has mainly succeeded and we have today homogenous production forests that give a high profit to the owners. The aim of the study is to compare the state of the forest in the former state forest Hällforsmarken in the years 1925 and 2000 and to interpret the changes which has taken place.
Transition from nomadic pastoralism to livestock based agro-pastoralism : the case of animal husbandry in West Pokot, Kenya
West Pokot County is located in North Western part of Kenya where the previous lifestyle was nomadic pastoralism. However, in recent years the semi-arid county has been under
dramatic developments and a sedentary agro-pastoral lifestyle is now growing. This is a major change in production systems and there is a big knowledge gap especially for the livestock based agro-pastoral systems. The main objective of this study was to investigate
the current situation of animal husbandry in West Pokot. Twenty farmers were interviewed in Chepareria Division, using semi-structured interviews to investigate if the use of enclosures have had any effect on animal husbandry in West Pokot and if so, how have this method affected the animal husbandry? The results of the study indicated that there is a difference in animal husbandry between farms using enclosures and farms not using enclosures.
Clover (Trifolium spp) gamefields : forage production, utilization by ungulates and browsing on adjacent forest
Wildlife is a valuable and renewable resource that promotes economical, ecological and social values. These values are important for developing and maintaining many rural societies. However, growing ungulate populations have led to increased browsing pressure on valuable forest trees and crops. Previous studies have proposed supplementary feeding and gamefields as potential methods for controlling the ungulate foraging and reducing browsing damage by providing other attractive food resources. However, quantitative estimates of potential biomass production of various gamefield crops and browsing pressure on the surrounding forest have been lacking.
Konstruktion av maskin för Tillverkning av sågblad
The saw blade producer, Håkansson Sågblad AB, patented in the U.S. a new blade profiledesigned specially to cut fish and meat. The most important advantage of that blade is that its teethare not set, therefore the material lost when cutting is really smaller. The special geometry of thatprofile made that nobody had found a proper way to produce it before.The goal of the outlined work is to develop a machine to produce these new blades in afeasible way.The research approach of the project can roughly be divided into three phases:1.- Invention and development of a proper distribution of blades to produce a big amount ofthem at the same time.2.- Research of the best production process to produce the blades.3.- Main design of the machine to produce the blades.In the Thesis these three points are carefully developed and studied in the form of the startpoint of a really bigger project. Some tests had been done in order to prove all the analytical ideasand the results obtained had been satisfactory enough to give Håkansson the start point of a bigbusiness.
Biokemisk och immunologisk karaktärisering av pepsin-spjälkade mjölkallergener
Milk allergens were digested by allowing them to flow through a chromatography column, where pepsin was conjugated to the stationary phase of the column. The allergen fragments were then characterized both biochemically, by using SDS-PAGE and gel permeation chromatography, and immunologically, by examining their reactivity to IgE and monoclonal antibodies..
Erfarenhetsåterföring :
This thesis has been done in collaboration with Peab Stockholm Building 3, which is a region within the Peab Sverige AB. The report is based on a survey and studies of Peab business management systems and production literature. For general information gathering has literature from well-known sources collected in libraries and through the Internet. It shows through the work that Peab has routines for experience feedback in the construction process, but that these procedures work in a small scale and the practical work experience feedback does not work at all. This is also something the construction industry in general also perceived as problematic. The questions in the report are of a wide scale and concerns construction errors cost, how the employees perceive that the company takes advantage of the skills and the mental stress in production line. The goal is to find how Peab Stockholm Building 3 will work on the experience feedback to allow for better productivity. In conclusion, the report author tries to demonstrate what can lead to increased productivity and improved work experience..
Risk för spridning av ogräsfrö med rötrester : en litteraturstudie
With an increasing production of biogas follows an increased amount of digestate. This could potentially be a valuable source of fertiliser with the destruction of weed seeds as a possible advantage. However, there have been some concerns regarding the product still containing viable seeds of weed.
In this Bsc thesis the results of previous research on the fate of weed seeds in biogas production is summarized. It is also a comparison of research on the effect of similar processes such as silage, compost or animal passage on seeds. The purpose of this is to evaluate risks of spreading viable seeds, potentially problematic species and perhaps to find out how to eliminate the risks.
The literature review revealed that previous research mainly indicates low risks regarding many of the tested weed species, but not all studies show the same result, therefore extended research on the subject is desirable.
LUT ? En metod för systemutveckling med lean software development
Traditionell systemutveckling präglas ofta av långa utvecklingsprocesser och en oförmåga attmöta förändrade behov från kunden. Problematik med buggar i mjukvaran och förskjutnadeadlines uppstår kontinuerligt och leder till högre kostnader för företag.För att komma till rätta med dessa problem behövs en systemutvecklingsprocess som belyserproblem direkt när de uppstår och därmed tvingar de inblandade till reflektion över processensom skapar problemen vilket belyser de verkliga bakomliggande orsakerna. Låg kvalitet påmjukvara är ofta ett symptom på djupare organisatoriska problemEtt synsätt som syftar till att möta dessa problem är lean software development. Synsättet harinspirerats av lean production som är en beskrivning av The Toyota Production system vilketi sin tur är det arbetssätt som har tillämpats av Toyota under flera decennier i den traditionellatillverkningen.Mary och Tom Poppendieck har beskrivit sju principer och 22 tankeverktyg som kananvändas för att skapa en metod för lean software development. Studien visar vilka styrkoroch problem som lean software development och lean production beskriver generellt samtvilka styrkor och problem som finns avseende beskrivning av Poppendieck's principer ochtankeverktyg i synnerhet.
Hälsoeffekter från trafikbuller vid Bäckegatan
The purpose of the study is to investigate the possible effects of an unstable ventilation system and its influence on energy use and thermal comfort. The report also explores how qualified personal working with HVAC view and handles system control.In order to meet the requirements in energy efficiency and a comfortable indoor climate control regulation is a prerequisite. With optimized increased complexity of the climate systems, it becomes more challenging to control the system and the risk of unstable control increases. No previous studies about what affect an unstable system can have on energy use and thermal comfort have been found.The report is based on several tests were the controlling variable has been increased until the system becomes unstable. Two different types of unstable systems have been investigated.
Påverkan på energianvändning och termisk komfort vid reglerinstabilitet
The purpose of the study is to investigate the possible effects of an unstable ventilation system and its influence on energy use and thermal comfort. The report also explores how qualified personal working with HVAC view and handles system control.In order to meet the requirements in energy efficiency and a comfortable indoor climate control regulation is a prerequisite. With optimized increased complexity of the climate systems, it becomes more challenging to control the system and the risk of unstable control increases. No previous studies about what affect an unstable system can have on energy use and thermal comfort have been found.The report is based on several tests were the controlling variable has been increased until the system becomes unstable. Two different types of unstable systems have been investigated.
Fruktkvalitet inom äppelodlingen : en studie av och för Äppelriket Österlen
The main purpose of this Master Thesis has been to investigate issues concerning apple fruit quality in orchards of Äppelriket Österlen. The goal has been to develop a document, for future benefit towards growers and company management in the production of high quality apples.In order to investigate main issues of fruit quality, focus has been on statistics concerning apple varieties, age of the apple trees, new planting, orchard size and growers opinions. Nine growers have been interviewed to investigate opinions and contribution of different growing techniques to increased fruit quality.
The investigation showed high age of the trees in production and low rate of planting of new trees. Differences in fruit quality were highest between small orchards. Most growers were satisfied with their fruit quality and with their own measures made to improve it.
Matting of Natural Image Sequences using Bayesian Statistics
The problem of separating a non-rectangular foreground image from a background image is a classical problem in image processing and analysis, known as matting or keying. A common example is a film frame where an actor is extracted from the background to later be placed on a different background. Compositing of these objects against a new background is one of the most common operations in the creation of visual effects. When the original background is of non-constant color the matting becomes an under determined problem, for which a unique solution cannot be found. This thesis describes a framework for computing mattes from images with backgrounds of non-constant color, using Bayesian statistics.
Ett tv-formats utformning mot publicering på webben: Skall television utvecklas, anpassas och förändras utifrån sin publik?
Watching television (TV) has been given a new meaning, you don?t have to book a specific time, a specific date if you don?t want to miss the program you were planning to see. In Sweden now days we can watch TV in lot of different ways, whenever we choose to do so. In this thesis I attempt to explain and document the process of shaping a tvformat, the development and adaptation to a time when the TV medium is in a change. Plus a look at how the television audiences relate to their use of it.
Drivkrafter bakom den totala faktorproduktivitetens utveckling på regional nivå : En fallstudie på de svenska FA-regionerna under perioden 1990 ? 2005
Production requires the input of capital and labour. Hence, economic growth can be assumed to follow from increased levels of these two factors. Policies aimed at increasing production may consequently successfully be focused on facilitating the accumulation of capital and labour. However, even when an economy has managed to reach the same quantities of input factors as a more prosperous neighbour, the level of the production might still differ. The explanation of this lies in what economists refers to as expression embracing the characteristics of the input factors and the conditions in which they operate.In this thesis a calculation of total factor productivity is carried out, using existing data on the Swedish FA-regions between 1990 and 2005 and the method the economist Robert Solow in the 1950?s.