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548 Uppsatser om Carbon dioxide emissions - Sida 23 av 37

Mean value modelling of a poppet valve EGR-system

Because of new emission and on board diagnostics legislations, heavy truck manufacturers are facing new challenges when it comes to improving the engines and the control software. Accurate and real time executable engine models are essential in this work. One successful way of lowering the NOx emissions is to use Exhaust Gas Recirculation (EGR). The objective of this thesis is to create a mean value model for Scania's next generation EGR system consisting of a poppet valve and a two stage cooler. The model will be used to extend an existing mean value engine model.

Urban agriculture : experiences from the Swedish horticulture

Urbanisation has increased the distance between the urban and the rural. Urban agriculture can be a solution to overcome that distance. The characteristic of urban agriculture is the intensive production in intra urban and peri-urban areas. Until 1950s food production in cities was an important part of the urban economy and the urban food supply. Since the 1950s the urban located production of food has almost ceased in Sweden, partly as a result of cheap food imports.

Grundvattensänkning till följd av järnvägstunnel genom Hallandsås : miljökonsekvenser relaterade till förändrad kväveomsättning i mark

This thesis was carried out to give some background information to a report of SLU (Swedish University of Agricultural Sciences) for the Swedish National Rail Administration (Banverket). The requested information was to provide basic data for an environmental impact assessment of the construction of the tunnel through Hallandsås. The aim with the thesis work was to discuss and quantify the leaching of nitrate and the emission of nitrous oxide from the soil at the groundwater level established through the tunnel project. The nitrogen related processes that could be affected were described and discussed. The different areas where a decreased groundwater level can cause changes in the nitrogen processes are the wet and moist areas.

Styrdokument för kontorsbyggnation ur ett ekologiskt hållbarhetsperspektiv : Aspekter och argument

The construction and real estate industry represents a significant part of Sweden's total impact on the environment and mainly affects the following national environmental objectives: reduced climate impact, a good built environment and a non-toxic environment. By establishing internal rules, companies within the industry can reduce their environmental impact. SMT (AB Sandvik Materials Technology), a part of the industrial group Sandvik AB, has set a target that during 2014 develop a guiding document with special consider to the environmental impact during construction of office buildings, that they establish at the Swedish regional capital Sandviken, for both internal and external tenants. This study therefore aims to clarify which environmental aspects that the construction and real estate sector mainly are responsible for, and therefore should be part of a guiding document for a company for establishing office buildings, and to present arguments regarding the use of such a document. The study is based on literature studies and personal contact with other companies, in the form of e-mail conversations and a telephone interview.

Konceptarbete om skidbalk i kompositutförande till BVS10

This thesis has been performed at BAE Systems Hägglunds, which is located in Örnsköldsvik. Hägglunds has a wide background of engineering, where they have manufactured all from airplanes to lifting cranes. Currently they only produce track vehicles at Hägglunds, where they manufacture the CV90 and BVS10 models. This thesis concerns the BVS10 which is an all-terrain-vehicle. The main purpose with the BVS10 is to enable transportation of material and personnel thru tough terrain.

Konstruktion av upprätningssystem för CICLoPE

Today there is no way of measuring or simulating turbulent flow in high Reynolds numberenvironments. The computational power required to simulate these conditions is not expectedto be available for several decades so instead the CICLoPE project aims at solving thisshortage by the construction of a long carbon fiber wind tunnel in which real measurementscan be made. To do accurate measurements it is of importance that the wind tunnel, 0.9 metersin diameter and 110 meters long, is as straight as possible.This master thesis treat the design and construction of a device which may be used to align thetunnel along a reference laser beam. A design is presented which allows the pipe to be alignedwithin about a quarter of a millimeter along its entire length. Contents span over severalscience fields such as physics, mechanics, control theory and electronics.The result is a theoretically correct design.

Effekten på nedbrytningen av rötter vid tillförsel av ammonium sulfat i en granskog i sydvästra Sverige

Decomposition of organic matter is a critical process in the ecosystem, which involves many essential biotic and physical parts. Decomposition is therefore an important process both above and below ground. The rate of decomposition is dependent of many environmental factors for example: pH, moisture and supply of oxygen. The decomposition can therefore be affected by large scaled environmental influences, such as acidification and climatic changes. The root litter in the forest is in different ways affected by acidification, liming and manuering.

Att bygga i trä eller lättbetong : en jämförelse mellan väggkonstruktioner

Hudiksvall Municipality will build a new preschool. The goal is that the pre-school should reflect the municipality's environmental goals and meet building regulations. The wall structures that are compared in the report is an insulated wooden frame and a frame of lightweight concrete blocks from H + HWall structures are compared within the areas of U-values, air tightness, thermal storage capacity, fire ratings, moisture, durability, emissions and environment. In these categories the two wall structures will be rated in a scale from 1 to 5 and then the categories are weighted against each other. The weighting is based on Hudiksvall Municipality's assessment of the categories importanse for their final selection.The results of the comparison show that the concrete structure is recommended for the construction of pre-school with 27.55 points against the wooden structures 23.70 points.

Företagens klimatbelastning : En fallstudie i beräkningar av CO2 ekvivalenter ur systemperspektiv - aspekter från näringslivet

I uppsatsen undersöks ett antal aktörer från näringslivet för att se hur de beräknar sin klimatbelastning. För att få fram en så korrekt utsläppsbedömning som möjligt behöver växthusemissionerna en kvantitativ grund där primära och sekundära utsläppskällor beräknas på den senaste informationen. Denna bas blir således ett verktyg för de organisationer som vill få fram ett kvantitativt beslutsunderlag för sina utsläpps/emissions faktorer och därmed deras totala klimatbelastning. Uppsatsen tar därmed upp ett mycket aktuellt och relevant tema för många företag, inte minst för de företag och organisationer som önskar klimatkompensera sina utsläpp av växthusgaser.En empirisk datainsamling genomfördes inom näringslivet som därefter analyserades med uppgift att belysa eventuella svårigheter som uppdagades i beräkningarna av utsläppskällorna..

Methane production from dairy cows : relations between enteric production and production from faeces and urine

Methane (CH4) is a greenhouse gas (GHG) that contributes to the global warming. One of the largest sources of methane is livestock, preferably ruminants which alone counted for 30% of the total agricultural anthropogenic methane emissions in the year of 2000. The reason to why ruminants are such large contributors of methane are that the gas is produced in the rumen by enteric formation and leaves the animals by belching, exhaling or by the excreta.Diets high in concentrates can result in a lower emission of methane. Also diets with a high content of starch, such as alfalfa-grass, have a methane-decreasing. It is profitable to reduce enteric methane formation since that form of methane is unavoidably lost.

Utveckling av nyckeltal för logistiska tjänster : En studie vid logistikföretaget Foria

The purpose of this thesis is to identify and define Key Perfomance Indicators (KPIs) and value adding services which are used to describe the quality of Forias logistics services from different aspects. The KPIs should be attractive to both Foria and their customers, with the aim to strengthen the interaction between both parties.The basis for this work is a research in which a literature review and a survey of the market for Swedish logistic service providers were carried out. An analysis of the present situation of Foria was carried out, where a number of people in the company were interviewed. These elements were used together with definitions of KPIs to perform the analysis of the work.The result of the work is ten KPIs that have been created and developed for Foria and which are considered to be attractive to both Foria and the selected customers. The KPIs are: · ECO-driving (binary) ? the company has ECO-driving-educated drivers· ECO-driving (comparison figure) ? all drivers individual driving and its resulting exhaust emissions are compared· The environmental impact ? a total of exhaust emissions from all vehicles belonging to a single business, measured in tonne-kilometres· Complete order ? portion of fields with accurate information (in an order), with the possibility of error categorization· Delivery reliability ? time difference between expected and actual delivery, average for all orders· On-time ? the number of days and hours of difference between the expected and the actual time, for all activities of the order· On-time (activity) ? the number of hours and minutes of difference between the expected and the actual time, for each individual activity of the order· Divergence ? a categorization of all causes of divergence and its responsible department· Level of integration ? the level of cooperation between the logistic service provider and the customer· Customer satisfaction ? how well an order will meet the expectations of the customer The KPIs are described in detail with definitions, how they can be used and what is required to implement them in the service process of Foria.

Vattenkvalité i Märstaån : Igenväxning som indikator på närsaltläckage och vattenstatus

The purpose of this study was to examine whether an inventory of the vegetation overgrowth could be used to indicate a locally nutritional impact. The study was conducted at Märstaån where the water runs through a number of agricultural lands that could lead to an increased amount of diffuse emissions of nutrients. The vegetation overgrowth in the water was also studied in relation to shade, meandering and water flow effects on the vegetation. With this method, no definitive conclusions could be drawn.Where the water was shaded, no vegetation overgrowth could be found. Therefor trees should be planted to prevent any future overgrowths.

Energieffektiva byggnaders påverkan på CO2-utsläpp : Norra Djurgårdsstaden i samarbete med Grontmij AB

Detta examensarbete har genomförts i samarbete med Grontmij AB och är ämnat att ta fram tre olika förslag på byggnader med samma utformning men uppförda med olika material i klimatskal och stomme, för att jämföra dess energiförbrukning och slutligen analysera koldioxidutsläppen som genereras. Målet med denna studie är att påvisa vilka material som lämpar sig främst vid hållbart byggande, vilka materialval som främst kan föredras när man vill uppnå energieffektiva byggnader samt analysera dess koldioxidutsläpp.Målet är att påvisa att koldioxidutsläppen minskar med enligt de upprättade miljökraven från Stockholms Stad i samarbete med Clinton Climate Initiative.Climate Positive Development Program lanserades år 2009 och är ett gemensamt initiativ mellan Clinton Climate Initiative och US Green Building Council. Programmet stödjer 18 projekt världen över och Norra Djurgårdsstaden är ett av projekten som ska vara en förebild för framgångsrik ekonomisk och miljömässig stadsutveckling. Programmet är även en vägledning vid byggande av bostäder vilket är avgörande för evolutionen av stadsbygget.Utvecklingen kring byggande har med tiden förändrats och anpassats till mer miljövänliga och energieffektiva alternativ. Idag har det blivit mer vanligt att tala om energieffektiva byggnader och minskade koldioxidutsläpp, vilka är betydelsefulla faktorer som påverkar miljön och vår framtid avsevärt.

Design av en ejektorspädare samt ett system för partikelmassmätning av dieselavgaser

This master thesis was a subtask of a project called EMIR-1. The goal with the thesis was tobuild a system for particulate mass measurements in one of the engine test cells at KTH. Theparticulate mass measurements are planned to be measured with a TEOM.The exhaust gases must first be diluted with air before the sample is sent to the TEOM.Therefore an ejector diluter for this matter also was designed and evaluated in the thesis.Emissions measurements have been done both with and without dilution to determine thedilution ratio. Tests have been done for different speeds and loads.Problems with stability of the dilution ratio have been an issue throughout the process andpressure pulsations in the exhaust pipe are believed to be the cause. More tests have to be done tomake sure that this is the problem.One idea is to make the inner diameter of the diluter nozzle smaller and see if it changes thedilution ratio stability.

Påverkar järninjektioner risken för ledinflammationer hos smågrisar? :

Hemoglobin is built up from protein and heme groups which give the blood its red colour . Hemoglobin transports oxygen and carbon dioxide between the lungs and other tissues in the body. Normally, a piglet has a hemoglobin value of 130-150 gram per liter blood, and the lower limit before anaemia appears is 80 grams per liter blood. The immune defense is also dependent upon the presence of iron in hemoglobin, since iron participates in different enzyme systems. When the piglet develops anaemia, it becomes pale and thicker around the neck.

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