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903 Uppsatser om Organic reduction - Sida 50 av 61

Metoder för lastprioritering i fjärrvärmecentraler

A problem in the field of district heating is the oil burners needed to provide power when a peak load occurs. One possible way of reducing the needed amount of oil is to reduce the power demand for space heating in the district-heating substations when the need for district heating water exceeds a certain limit. This can be done by use of a locally working controller function.In this Thesis the options concerning load priority are evaluated. To evaluate the potential for using controller functions concerning peak load priority an experiment was brought out in a chosen district-heating substation. The impact on the indoor thermal comfort during a heat reduction was also taken into account.

Säkring av samtliga kritiska skruvförband i mellanstora asynkronmotorer

The purpose with this thesis is to get a compilation of all the critical bolted joints of all enginesproduced at LV Motors. ABB LV Motors produces induction engines with seven shaft heights. Eachengine size exists several variants of components ex. standard shield and flange shield. Depending onwhich components the engine is equipped with arises various types of strains in the engine's parts,certain assembly ways are more favourable than other.The most critical parts in the engine from a mechanical point of view are the screw units betweenshield/stator, feet/stator and bearing cover/shield.

Kustnära ekosystem som skydd mot naturkatastrofer : en litteraturstudie från ett riskhanteringsperspektiv

Research suggests that society's vulnerability to natural disasters along coasts could increase as a result of climate change, which is likely to lead to elevated sea levels and possibly an increase in the occurance of meteorological phenomena such as storms and tropical cyclones. Following the Indian Ocean tsunami disaster in 2004 and Hurricane Katrina in 2005, both of which received considerable media attention, empirical data has indicated that coastal vegetation might be able to protect and reduce damages to coastal communities during tsunami events and tropical cyclones.The aim of the essay has been to study the function of coastal ecosystems as protection against tsunami waves and storms from a risk management perspective, meaning that I have, through an overview of scientific articles, compiled current research on how coastal ecosystems can attenuate storm surges and tsunami waves, and analysed how this knowledge can be put into practice in coastal communities from a risk management perspective, i.e. if coastal ecosystems are a viable risk reduction measure, are practically applicable, and if so, how they could be applied.There is empirical evidence suggesting that coastal ecosystems, particularly mangroves, can reduce the strength of a tsunami wave, but full scientific consensus on this issue has not yet been reached. With regard to protection against storm surges, there is extensive scientific evidence that coastal vegetation can mitigate damages and reduce the height of a storm surge, although the wave has to traverse several kilometres inland through thick vegetation for the protection to be effective. A synthesis in the form of a figure regarding the many physical factors that influence wave development through coastal ecosystems has been created in an attempt to simplify and explain the phenomenon.The conservation and restoration of coastal ecosystems can be justified from a risk management perspective, but planting new forest belts for the purpose of disaster mitigation is quite unrealistic and can rarely be sustainable, since, for protection to be effective, the forest belt must extend several kilometres inland from the coast, and would thus likely prove difficult to implement along coastal societies..

Aktivitet, läggnings- och resningsbeteenden, tillväxt samt renlighet hos kvigor i liggbås respektive djupströbäddsbox :

The aim of this study was to compare activity, lying down and getting up behaviour, weight gain and cleanliness in heifers in cubicles versus on deep-litter. The study was conducted from autumn of 2005 until autumn of 2006 in a commercial organic dairy herd with 340 cows. In 2005 the farm rebuilt half of the young stock accommodation from deep-litter pens to cubicles. The experiment used 150 heifers of the breeds Swedish Red, Swedish Holstein and crossbreeds between these, all born on the farm. The animals were divided into three blocks based on breed and within each block they were sorted after increasing age. The youngest heifer in each block was randomly allocated to one of two groups, cubicle or deep-litter pen.

Impact of Eucalyptus plantations on pasture land on soil properties and carbon sequestration in Brazil

Soil organic carbon (SOC) stocks and fluxes in forest ecosystems are influenced by natural and human disturbances. In the tropical regions the highest impacts on disturbance in forest C cycles are related to human activities such as conversion of natural lands to cropland and pasture areas and to forest plantations. The disturbances in the forest C cycles will release CO2 emissions to the atmosphere triggering global warming. In this study the focus was set in subtropical soils in Brazil, south extreme region of Bahia. The aim of the study was to investigate whether reforestation of Eucalyptus plantations under former pasture areas will help mitigate climate change through carbon sequestration.

Potentiell fosforfrigörelse från sedimentet i Bornsjön, sydvästra Stockholm : The potential leakage of phosphorus from sediment in Lake Bornsjön, south western Stockholm

Lake Bornsjön is situated 30 km southwest of Stockholm in a rift valley lake and consist three basins outstretched in northwest-southeast direction. The surface area is 6,7 km2 with a maximum depth of 18,3 meters, a mean depth of 9,8 meters and a retention time of the water of 6,5 years. The drainage area is 42 km2 and consists mainly of arable land (ca 1000 ha) and productive forestry land (2500 ha), but in the drainage area there are also restored and fairly newly constructed wetlands.Today the Stockholm area receives its drinking water from Lake Mälaren, but if there would be any pollution of this source, Lake Bornsjön would act as the water source. The area surrounding the lake was bought already in 1899 by Stockholm Stad for protection of the lake and was taken over 1993 by Stockholm Vatten AB. It has been a water protection area from 1988 and it was also accepted as a nature reserve in 1995.

Concentration and offtake of trace elements and macronutrients in Italian ryegrass (Lolium multiflorum Lam.) and spring barley (Hordeum vulgare L.) grown on soils amended with water treatment residual sludge

Aluminium sulphate (Al2(SO4)3) is usually added during the drinking water treatment processin order to precipitate organic and inorganic material, resulting in aluminium-based drinkingwater treatment residual sludge (WTR). Since 2003 Swedish law no longer permits WTR tobe deposited in lakes, and there is an interest to explore the possibility to utilize WTR as soilamendment. The aim of this study was to examine the effects of WTR application on cropgrowth and concentrations of macronutrients and trace elements (including micronutrients andpotential toxic elements). A greenhouse pot experiment was conducted with three soils; a clayloam rich in phosphorous (P), a loamy sand rich in P, and a silty loam with a low soil Pconcentration, and two crop species Italian ryegrass (Lolium multiflorum Lam. cv.

Undervegetation : användning av vedartade marktäckare i anläggning

The use of the robust and durable woody ground covers is increasing, not in the least in public places. The group includes low shrubs of different height that effectively build low, tight vegetation that covers the ground. Despite all the good qualities the knowledge about them is quite low and there are ideas about them of being dull. The woody ground covers manage to struggle against weeds effectively by competing for nourishment and water, but above all, by the canopy of the ground covers that prevent the weeds from getting enough light. In that way the woody groundcovers can effectively compete with the annual weeds.

What traits make Swedish dairy cows survive?

The ability of dairy cows to survive and the economic importance of this have been in-creasing in dairy cattle breeding lately. Increased longevity contribute to an increased pro-portion of cows that produce milk in more productive lactations and reduces the replace-ment costs together with a good health and fertility. Unfortunately it is often argued that longevity has been decreasing due to a strong selection for production traits in dairy cattle.The aims of this study were to find correlations between different longevity evaluations and between different estimates on longevity and other traits in the Nordic Total Merit (NTM) breeding value. The aim was also to compare different traits for cows of two differ-ent longevity groups.The data were Predicted Breeding Values (PBV) from Nordic HOL and SR bulls and records from Holstein (HOL) and Swedish Red (SR) cows estimated by the Swedish Dairy Association.The three Swedish longevity indexes were very highly correlated (>0.89) and the corre-lations between the Swedish official longevity index and the five Nordic Cattle Genetic Evaluation (NAV) longevity indexes varied between 0.73-0.83.In the sire evaluation part, the traits most negatively correlated with longevity for HOL were dairyness, protein and fat index. In SR, milk, protein, and fat index only had slightly positive correlations with longevity.

Energieffektivisering i ett reningsverk för skogsindustriellt avloppsvatten genom förfällning av extraktivämnen

Pulp- and papermills expend vast amounts of water in order to produce pulp, paper and cardboard. Hence, they alsocreate vast amounts of waste water which has to be cleaned before it can be released into the receiving body of water. Insuch a wastewater treatment plant, tremendous amounts of energy are expended by the aeration in the biologicalcleaning process. This aeration is necessary to supply the microorganisms that shall decompose organic material withoxygen, which they need for their metabolism. The transfer of oxygen from the gas phase to the liquid phase isprimarily inhibited by surface-active substances in the waste water like resin acids or fatty acids.

Stadsodling : möjligheter och begränsningar

Urban farming can be viewed in several contexts. The first part of this work brings up the beneficial effects of farming on our physical and mental health, knowledge as well as on social life in cities. The introduction of gardening in schools can contribute to an increased awareness on both agricultural practices and importance as well as ecological processes. It can also be used in teaching of other subjects. Farming can also contribute to improving the household economy, and the economy on a municipal or national level.

Privata och offentliga riskreduceringsmekanismer och dess inverkan på beviljande av handelskrediter

Bakgrund och problem: Majoriteten av försäljningen mellan företag, samt mellan företag och offentlig sektor sker via handelskrediter. Detta leder till att företagen ofta blir utsatta för risker i form av sena och uteblivna betalningar. I sådana situationer finns det behov av riskreduceringsmekanismer som ska reducera och minimera dessa risker. Mekanismerna för reducering av risker har vi fördelat i två kategorier, privata och offentliga. Avsikten med uppsatsen är att undersöka vilka av dessa mekanismer som har störst inverkan på beviljandet av handelskrediter.

Effekten av längre tids praktiserande av mindfulnessmeditation på hjärnfunktion och struktur ? en summering utifrån nyare studier av vipassana- och zenmeditation

Västerländsk mindfulnessmeditation har sina rötter i tusenårig buddhistisk tradition, främst genom vipassana- och zentraditionerna. Senaste tiden har mindfulness ökat i popularitet och blivit en accepterad klinisk metod i former som mindfulness based stress reduction. Möjligheten att undersöka dess effekter genom neurovetenskapliga metoder bidrar med intressant och viktig forskning om mänskligt välbefinnande. Dock har tidigare studier visat på bristande samstämmighet vad gäller resultat och metod. Uppsatsen är en litteraturstudie där det huvudsakliga syftet är att utifrån nyare studier undersöka de tydligaste effekterna på hjärnfunktion och struktur av långvarigt praktiserande av mindfulness utifrån vipassana- och zenmeditation.

Utveckling av processparametrar inom en hårdmetallindustri

This report analyzes and examines a hypothesis for finding a method to optimize thelength of the delubrication process time based on a total charge weight. The work hasfocused on the holding time for delubrication and the total charge weight.An important step in the manufacturing chain of cutting tools is when the greenbodies undergo the sintering process. Today, the delubrication step has the sameprocess time independent of the total charge weight. An implementation of a methodto adjust the delubrication process time would give more consistent quality of thecutting tool´s internal characteristics but also reduce the time course of the sinteringprocess. In the present project two methods for this goal were tested, thedevelopment of an algorithm and a weight interval subdivision with associateddelubrication process times.During delubrication a pressure increase is observed due to the decomposition of thePEG in the powder mixture.

Konvertering från direktverkande el i kommersiella lokaler : Ekonomisk och hållbar utveckling

Buildings worldwide account for 40 % of the total energy use. Climate change is of increasing importance, but few are willing to reduce their standard of living or get a higher cost for the change. Energy efficiency of existing buildings gives the greatest benefit economically and environmentally. The real estate company Klövern AB manages 46 properties in Karlstad. Heating is the major cost of the total operating costs of real estate. Rising energy prices increase the need for Klövern AB to improve energy efficiency and to investigate alternative sources of heat.

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