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1841 Uppsatser om Methanol; SECA; ECA; shipping; exhaust gas emission; alternative marine fuel - Sida 15 av 123
Aktiv ventilstyrning
To achieve an optimal combustion, an even air/fuel ratio in the combustion chamber is required. An optimal combustion leads to reduced amount of emissions due to a more complete combustion, which is an important matter because of the sharpened environmental laws. This can be attained, among other things, by applying entirely variable cam times. To optimize the engines efficiency and its emissions at all workloads and speeds, an active valve control can be applied. This means that the intake and exhaust-valves can be opened and closed at any time, independent of the crankshaft position.
Energioptimering : Resteffektkylning av mellanlager för använt kärnbränsle (CLAB) Oskarshamn
This thesis is done in cooperation with SWECO Energuide in Växjö. They have been assigned by SKB in Oskarshamn to renew their electrical power supply and the ancillary processing systems in their Central provisional storage of spent nuclear fuel, CLAB. Today in the CLAB facility, the spent fuel is cooled down with water pumps, driven by asynchronous induction motors, where the water is regulated by mechanical valves to the desired flow. After the upgrade, the engines will be powered by AC drives that can control the pumps by changing the rotational speed and thus change the water's cooling effect on the nuclear fuel. In this study, I investigated the interference AC drives causes the feeding network and how to go about averting them.
Museers marknadsföring mot hotell : Hur marknadsföringen har ändrats sedan återinförandet av entréavgifter
This study's main objective was to identify adolescents participation in alternative sport activities and which kind of physical activity that was preferred by adolescents who didn't had any earlier experience of sport clubs. The study combined interviews and surveys with the purpose to get both adolescents and sport leaders perspective. A total of five interviews were performed and fifty-four surveys was collected. The results showed that adolescents already physical active were those who participated in alternative sport activities. Who participate in alternative sport activities can depend on habitus, comprehended capital forms and in which social field the sport activities exists..
En jämförande studie av fem lastbilsmonterade flishuggar
The study was carried out as a time study of five wood chippers placed on trucks,so?called huggbilar. They are trucks with built?in wood chipper, chip bowl and crane pulling a chip trailer. The system is used for chipping wood fuel, transporting, and delivering the chips to heating plants.
Fossilfria godstransporter : En undersökning av alternativ till diesel som drivmedel för lastbilar
Our modern society is in many ways built with and dependent on fossil fuels, which are used for energy production as well as for transporting humans and goods. Without the oil, many of the things we take for granted would not be possible. During the last century, the use of oil has increased steadily and will probably keep increasing as the world population and the economic well-being for many people increase. Since the oil is a finite resource, we will have to find other fuels that can replace it if we want to keep the same rate of development in the future as the availability of petrol fuels will decrease with rising prices as a result. Furthermore, fossil fuels have the disadvantage that they produce harmful emissions when combusted and thus affect the climate and air quality locally and globally.
När förmänniskan blev den moderna människan
The subject of this bachelor-level thesis in archaeology in the transition from archaic sapiens to anatomically modern humans, and what might have caused this transition. A part of the study aims to prove or disprove whether an increased consumption of shellfish might have caused this development. Another part of the essay deals with the connection of said evolution and the suggested emergence of cultural and ritual practices in South Africa circa 100 000 BP and an evaluation of the arguments concerning the aquatic ape hypothesis, and their usefulness for the subject.The result of investigation of the theory about the increased consumption of marine resources as a probable cause of the last biological step of creating our species points to the conclusion that it is a probable explanation. There is even some evidence that there could be a connection between consumption of marine resources and the "Out of Africa 2"-theory. It is harder to find a proven connection between the suggested emergence of cultural and ritual practices, even some evidence seems to strengthen the idea.
Alla ska med : en etnografisk studie om Stena Bulks unika företagskultur
AbstractCorporate cultures have since the 80's, when the phenomenon was associated with a company's economic success, been a frequent research object. Corporate culture is then often described as something that can create efficiency, success and loyal employees. Often discussed about strong corporate cultures are that members in the organization have accepted the same norms, values and goals. Research also mention unique corporate cultures, where no organization is alike, depending their different stories, leaders, backgrounds or geographical locations.?? This study aims, through observations and interviews on an ethnographic basis, to describe the corporate culture in Stena Bulk.
Ekonomi vid uttag av långa toppar som skogsbränsle i slutavverkning :
The market for biofuels from the forests have had a positive development and the job initiators for this master´s thesis wanted to examine the profitability of a method for harvesting forest fuel, which was unfamiliar to them. The method was the ?long tree tops-method?, here called the LT-method.
The LT-method is characterised by the fact that timber is harvested as the only roundwood assortment while the rest of the stem, which in other cases would become pulpwood, is harvested as forest fuel together with the logging residues. The method is based on the assumption that advantages in handling of the forest fuel assortment such as increased load weights for forest hauling and truck transportation, should compensate for the lower price for pulpwood when sold as forest fuel.
The aim of the study was to compare the profitability of the LT-method with the GROT-method (harvest of timber, pulpwood and logging residues) and conventional logging without any harvest of forest fuel, and aslo to try to identify factors affecting the profitability of the different methods.
Renovering av flerfamiljsbostäder inom miljonprogrammet ur ett energi- och lönsamhetsperspektiv
Miljonprogram is a Swedish building program from 1964 to 1975. During that time about a million homes were constructed. Now, almost 50 years later, they are in desperate need of renovation. In order to fulfil the Swedish environmental objective to decrease energy consumption 50 per cent until 2050, considerable housing stock built under the Miljonprogram has to be renovated.Focus in this thesis is on the building services and theirs profitability that can decrease energy consumption in households build during the Miljonprogram. Building construction is not considered in this report.
Grundläggande rättigheter kontra ekonomiska friheter efter Lavalmålet : förhandlings- och strejkrättens utveckling genom tillämpning av internationella instrument, EU-rättens förändring och svensk normhierarki
This study's main objective was to identify adolescents participation in alternative sport activities and which kind of physical activity that was preferred by adolescents who didn't had any earlier experience of sport clubs. The study combined interviews and surveys with the purpose to get both adolescents and sport leaders perspective. A total of five interviews were performed and fifty-four surveys was collected. The results showed that adolescents already physical active were those who participated in alternative sport activities. Who participate in alternative sport activities can depend on habitus, comprehended capital forms and in which social field the sport activities exists..
Integration av simuleringsmodeller för bränslesystemet i JAS 39 Gripen
In this final thesis two simulation models have been integrated. The simulation models are models of JAS 39 Gripen?s fuel system, software and hardware. The time consuming and costly work to develop software has made the department of fuel system to build two models in Xmath/Systembuild. The software model also simplifies the comprehension of how the software in the control computer of the fuel system works.
Syntes och egenskapskarakterisering av volframoxid framställd med magnetronsputtring
The system tungsten-oxygen has potential of being suitable for decorative coatings since ceramic coatings are often hard and wear resistant, and since modulations in oxygen content or incorporation of small ions could give bright colours. The aim of this report was to investigate the relationship between process parameters and the properties of the films, with the wear resistance being of special interest.Samples with tungsten to oxygen ratios in the range of 100:0 to 25:75 at% were made using reactive sputter deposition, either with constant gas flow, or gas flow controlled by optical emission of the plasma. The hysteresis of the system, which means that a certain gas flow will cause different pressure and/or target voltage depending on in what way the flow is reached, makes it interesting to control the process where the system makes the steep change from metallic tungsten to ceramic tungsten oxide. This is difficult and thus requires precise control equipment.The samples were analysed using X-ray diffraction, X-ray photoelectron spectroscopy and an empirical wear test suitable for small components like cell phone cover for example, in order to characterize the structure, composition and wear resistance of the coatings. The results could be divided into three groups: (I) tungsten-like, with very low oxygen content; (II) mixed phase and (III) tungsten oxide like, with oxygen content close to 75 at%.
Energieffektivisering av industribelysning : Planering av belysningsanläggning i mekanisk verkstad
In Uppsala, Sweden, Vattenfall has a combined heat and power plant. On the premises there is an engineering workshop with old fluorescent and mercury lamps that need to be replaced. This provides a great opportunity to save energy and money by installing more efficient lighting. The main purpose of this study was to present two functional and energy efficient lighting systems including control system. The lighting systems were designed by investigating the working environment, measuring illuminance and by simulations in the software DIALux.
Förbättring av hanteringen vid utrikesfrakter på ITAB Shop Concept AB Jönköping
Our purpose with this report is to create a structural basis over how to improve handling with international freight at ITAB Shop Concept (further mentioned as ITAB). We have through interviews with employees at ITAB and observations identified problems that have caused difficulties at handling with international freight, from the time when an order is placed to when it?s delivered to the customer. We have also interviewed shipping companies.We have in the theory chapter written about shipping conditions for international freight and a main part of our theory is about NSAB 2000, which describes the obligations and rights shippers and consignee has.In order to improve the efficiency ITAB has to be aware of the problems in the company and try to solve them.The problems we have identified are described in the result chapter. One of the problems is that employees at the warehouse don?t know when gods is supposed to be shipped.
Vätedriven förbränningsmotor : Klarläggande av framtida hållbarhet
Today when new and harder demands on CO2 emissions are developed, vehicle manufacturers must work to develop new engine solutions to new kinds of fuels to replace fossil fuels. A fuel that could be applied is hydrogen. When hydrogen is combusted only water vapor occurs. Hydrogen is known to be explosive and flammable. These properties are both good and bad for combustion.