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411 Uppsatser om Excess yield - Sida 17 av 28

Kalkningens påverkan på fosforlöslighet : skakförsök baserade på två svenska långliggande kalk- och fosforgödslingsförsök

Eutrophication is an environmental problem that affects more than ten percent of Swedish lakes. Excess nutrients increase the growth of algae, and cause major problems in the ecosystem through oxygen-free bottoms, fish kills, and at worst dead bottoms. Agriculture accounts for 44% of human emissions of phosphorus to lakes and rivers. Leaching occurs of particle bound phosphorus and of dissolved phosphate. The amount of phosphate in the soil solution that may be leached is partly due to the prevailing pH in the soil solution. The purpose of this study was to investigate how the relationship between phosphate solubility and pH was affected by liming.

Milk production in dairy cows and goats : a case study in the Nyando district inSouth-Western Kenya

Water is an essential factor for both people and animals, and access to water is therefore of great importance. The water access also largely determines the availability of food for people and feed for animals. The aim of this study was to survey the affect of water access on milk production from dairy animals. The study included nineteen farm visits that were made in the Nyando district in Kenya between February and Mars 2011. Farm visits included interviews with questions about for example number of dairy animals, milk production, water access, feed and water routines.

Skapandet av ett integrerat ledningssystem

To be able to compete on the market environmental Management System has become an important part of operations work. However, many companies still haven?t implemented an environmental management systems due to lack of time and the high costs. One of the companies with this problem is Falu Bildemontering. Their goal is to accredited according to the ISO 14 001 certificate.

Optimering av driftläggningar i Fortums nät

Future emission legislation puts great emphasis on increasing the efficiency of the engine, thereby reducing fuel consumption. The tribological contact between cylinder liner and piston ring is where an great amount of energy is lost due to friction, and by reducing these losses an reduction in fuel consumption can be achieved.The aim of this thesis was to evaluate the tested piston ring coatings against a plasma sprayed cylinder liner and rank these combinations of materials for friction and wear resistance. The coatings that were tested was Cr + Al2O3, (Al,Cr)N, two types of CrN and WC / C.The experimental tests were performed with a so-called pin-plate, where used oil with addition of an acidic mixture of sulfuric and nitric acid to mimic the acidic condensate formed when exhausts recirculate, were added with a continuous flow. The results were then analyzed by weighing, studies by optical microscopy and scanning electron microscopy (SEM) and profile measurements.The results from each material combination were that the plasma coated cylinder liner wears too aggressively in order to yield a ranking of the piston ring coatings based on the parameters of friction and wear resistance. It is therefore proposed that an alternative coating on the cylinder liner should be developed, lacking the large abrasive wear on piston rings and that can withstand the corrosive environment resulting in engines equipped with EGR.

Likviditetsstrategi på Stockholmsbörsen : En studie om likviditetspremiens existens och dess eventuella överavkastning

Bakgrund: Det har tidigare konstaterats att det existerar ett samband mellan aktiers likviditet och dess avkastning. Bevis för detta har främst gått att finna på utländska aktiemarknader. På den svenska aktiemarknaden har tidigare utförda studier konstaterat att detta samband inte existerar. Vi vill därför göra en studie på den svenska aktiemarknaden, vilken delvis innefattar en ny tidsperiod för att se om någon likviditetspremie existerar.Syfte: Vårt syfte med denna studie var att undersöka om det är möjligt att uppnå en högre avkastning genom att investera i en portfölj med relativt sett illikvida aktier jämfört med en portfölj bestående av likvida aktier på Stockholmsbörsen samt undersöka om faktorerna likviditet, betavärde samt företagsstorlek signifikant påverkar portföljernas eventuella överavkastning jämfört mot ett lämpligt index.Metod: Vi har skapat tre olika portföljer, med tio aktier i varje vilka representerar de minst, mitterst och mest likvida aktierna enligt vårt valda likviditetsmått, aktieomsättningshastighet. Likviditetsmåttet laggar en månad för att kunna användas som investeringsstrategi.

Ny metod fo?r ma?tning av va?gkvalitet : En statistisk studie o?ver samband mellan va?gkvalitet och socioekonomisk utveckling

New method for measuring road quality- A statisticalstudy of the relationship between road quality andsocioeconomic development A new tool with implications for road maintenance has the potential to yield statistical data for road quality in a large number of regions. This thesis investigates the possibility to develop a method, from this data, for evaluating the effects of road quality on socioeconomic development.The thesis is essentially divided into two parts. Part one looks to qualitatively establish the link between socioeconomic development and road quality and the second part focuses on how to develop a method for evaluating the effects of road quality on socioeconomic development. A method was devised using categorical data and a multinomial regression model. This method provides a comprehensive overview of the complex relationship between a variety of different variables.

Studie av belagda kolvringarmot plasmasprutat cylinderfoder : Med avseende på friktion och nötningsmotstånd

Future emission legislation puts great emphasis on increasing the efficiency of the engine, thereby reducing fuel consumption. The tribological contact between cylinder liner and piston ring is where an great amount of energy is lost due to friction, and by reducing these losses an reduction in fuel consumption can be achieved.The aim of this thesis was to evaluate the tested piston ring coatings against a plasma sprayed cylinder liner and rank these combinations of materials for friction and wear resistance. The coatings that were tested was Cr + Al2O3, (Al,Cr)N, two types of CrN and WC / C.The experimental tests were performed with a so-called pin-plate, where used oil with addition of an acidic mixture of sulfuric and nitric acid to mimic the acidic condensate formed when exhausts recirculate, were added with a continuous flow. The results were then analyzed by weighing, studies by optical microscopy and scanning electron microscopy (SEM) and profile measurements.The results from each material combination were that the plasma coated cylinder liner wears too aggressively in order to yield a ranking of the piston ring coatings based on the parameters of friction and wear resistance. It is therefore proposed that an alternative coating on the cylinder liner should be developed, lacking the large abrasive wear on piston rings and that can withstand the corrosive environment resulting in engines equipped with EGR.

Kan mjölkkors utnyttjande av vallprotein bli bättre? : utfodringsstrategier och konserveringsmetoder

The purpose with this literature study was to investigate the possibilities for improvement of forage protein in dairy cows with focus on feeding strategies and conservation of forage protein. The utilization of forage protein in dairy cows is often not that efficient as it could be. The feed crude protein consists of both true proteins and non protein nitrogen. The digestion of proteins in the rumen depends on the protein degradation rate and the ability of the microbes to synthesize microbial protein. The microbes need a balance between carbohydrates that provide them with energy and proteins that are degradable in the rumen.

Skogstillväxten ca 20 år efter plantering på Flakmossen : dikningens och gödslingens betydelse vid beskogning på en avslutad torvtäkt i Värmland

This study was performed in an afforestation experiment established 1982 on an abandoned peat harvesting area, Flakmossen, in the province of Värmland, SW Sweden. The experimen-tal design include planting with Scots pine (Pinus sylvestris), in combination with various drainage intensities (20, 30, and 40 m between ditches), and fertilizer doses 0, 100, and 200 g PK per seedling applied at the date of planting. The aim of this study was to achieve more knowledge about the conditions on afforestation of peat harvesting areas, especially regarding drainage intensity and fertilization requirements, by means of determining the stand growth and yield in the Flakmossen trial. The forest growth did not differ significantly between the drainage intensities tested when the same amount of phosphor and potassium fertilizer was added. Thus, shorter distances between ditches than 40 m can not be recommended. When no fertilization was carried out seedling survival was very low, and the growth of sur-vived seedlings was poor. The largest diameter and height growth were observed in the areas where the highest dose of phosphorus and potassium (200g/seedling) was given.

Byggkostnader inom mjölkproduktionen - jämförelse av olika stallstorlekar och byggnadstekniska utföranden

Investment costs for eight different type housing systems for dairy cows has been calculated in order to compare the building costs as a function of herd size, shelter type and automatization. A commercial calculation programme for building was used and complemented with prices of equipments specific for dairy cow building. Herd sizes were 120, 250 and 400 cows. The milking equipments were automatic milking system (AMS), parallel parlour with 32 stalls (2x16) and rotary parlour with 24 stalls. Shelter was either insulated equipped with automatic cable driven scrapers on solid alleys, automatic feed wagon on rails, or uninsulated with manual manure handling and a tractor driven mobile mixer wagon on a drive-through feeding table. Building cost per cow or per kg milk was calculated using an average life time and 6 % interest rate and annual milk yield is 9 500 kg/cow and year. Structure effect 3-4 % higher for an insulated structure than in an uninsulated for 400 and 120 herd respectively. This is much lower compared to what is normally argued.

Vilka hinder förekommer utmed gångstråk och hur kan de åtgärdas : samt hur kommunerna använt resultatet från tillgänglighetsinventeringar och hur de upplevt stödet från Vägverket Region Mälardalen

To be able to compete on the market environmental Management System has become an important part of operations work. However, many companies still haven?t implemented an environmental management systems due to lack of time and the high costs. One of the companies with this problem is Falu Bildemontering. Their goal is to accredited according to the ISO 14 001 certificate.

Den skogliga informationens roll i ett kundanpassat virkesflöde : en bakgrundsstudie samt simulering av inventeringsmetoders inverkan på noggrannhet i leveransprognoser till sågverk

This MSc thesis is divided into two parts. The first part deals with the need for information from forest campartments selected for clear cutting, in connection with planning in an integrated forest- and sawmill enterprise. A review of literature is followed by a case stud y, where present conditions in a Swedish forest company are compared with current research in the area. The seeond part consists of a simulation stud y, which aims at camparing the accuracy of inventory estimates using different methods. The estimates are delivery forecasts, covering one month consumptian of timber in a large sawmill.

Traditional milk production in cattle in a semi-arid area in Kenya

Livestock of pastoralists provide meat, milk, blood, dung and are useful for transportation purposes. In semi-arid and arid areas with very low precipitation the herder must often walk far distances to feed the livestock. This affects the animals? production, especially of milk. Previous studies have investigated how to improve milk production in terms of milking strategies in cattle.

Mätramar för vederlagsmätning och timmersortering på sågverk

The measuring of logs is important in the sawmills process to the sawn products. The technology of automatic wood measurement is continuance developing. This study has the purpose to see how the different techniques and the routines works of measure frames for determining of wood value and sorting in sawmills. The study is performed as a literature study and a survey. The survey includes some of the Swedish sawmills that produce more than 10 000 cubic meters sawed products per year.

Täckning av plansilo :

With the increasing costs in concentrate the importance in producing ensilage with a high quality is becoming more and more important. To succeed with this goal it is of importance not only to harvest in the right period, but also to be able to store the ensilage without a decrease in quality and nutrional values. To maintain a good ensilage the covering of the ensilage must be carefully made. An unsuccessful covering causes mould to grow in the ensilage, which both increases the work load and also increases the amount of feed which is wasted. A bigger amount of spoiled feed also increases the risk of feeding spoiled feed to the cattle.

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