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4722 Uppsatser om Transport model - Sida 60 av 315
Frekvensreglering i det nordiska kraftsystemet
Svenska Kraftnät is (together with the other transmission system operators of the Nordic power system) responsible for keeping balance between the generated and demanded power in the Nordic power system. Spontaneous load variations and system disturbances, however, lead to power imbalance followed by frequency variations. The frequency deviations can be limited to an acceptable level by the spinning reserve, mainly by hydro power control. But there are also other system properties which have a great influence on the frequency and system stability. The frequency and voltage dependence of the loads have a direct influence on the power balance.
Mixture and single-compound toxicity using Daphnia magna : comparisons with estimates of concentration addition and independent action
Aquatic organisms are usually not exposed to single substances but rather to mixtures of toxicants in streams located in agricultural areas. The transport of pesticides used in the agricultural area in Sweden is monitored with continuous environmental supervision every year. During 2002-2008 an average of 10 pesticides were found in each sample and 40% of the samples contained substances with concentrations higher than the Water Quality Standards. Chemical risk management is normally based on single-test evaluations. A problem when assessing mixture toxicities is that the constituents and concentrations of pollutants in the environment vary greatly.
Energiförbrukning och utsläpp av koldioxid vid byggande av väg
Markförstärkning i ett vägbygge kan göras på olika sätt. I detta examensarbete jämför vi två av dessa metoder, nämligen massutskiftningsmetoden och användning av kalkcementpelare ur energi- och miljösynpunkt. För att jämföra dessa två metoder togs fram ett excelbaserat räkneverktyg där resultatet av energiförbrukningen fås i kWh och koldioxidemissioner i ton CO2. Denna jämförelse gjordes för ett specifikt vägprojekt som använde massutskiftningsmetoden för vägunderbyggnaden. Det som ingick i beräkningen var schaktning, fyllning, krossning, sprängning, transporter och kalkcementpelare.
Den kritiska Messengergenerationen : En studie om politiska diskussioner i sociala medier samt skolans roll i att forma kritiskt ta?nkande individer
The purpose of the study is to explore how social media can be used as a forum to discuss politics and also how young people use critical reflection to evaluate the information available on social media. To achieve the purpose, a qualitative research is used. The empirical data is collected through semi-structured interviews with six high school students who voted in the Swedish parliamentary elections in/of 2014. The empirical data were then analyzed based on previous research on social media, and the school's mission to foster individuals who think critically. The analysis is also based on the theory of deliberative democracy model.
Modellbaserad drivlinereglering
A cars powertrain consists of everything that is needed for its propulsion. The components in the driveline that transfer the power from the engine to the driven wheels are not absolutely stiff, hence they will wind up due to the torque and act as torsion springs. If you suddenly demand a bigger torque by stepping on the accelerator pedal, a so called tip in manoeuvre, and that torque is acquired from the engine as quickly as possible, the driveline will not be able to transfer that fast torque change due to its weakness and as a result it will start to oscillate. These oscillations will be transferred to the driven wheels and make the car to accelerate jerkily which will be experienced as uncomfortable by the passengers. Furthermore, there is a backlash in the driveline that will make the weakness in the driveline even more excited than it should have been if the backlash did not existed.To avoid too big problems with these oscillations there is a control system that controls the demanded torque.
Ledarskap inom ramen för ett systemutvecklingsprojekt - fokus på en arbetsprocess med stöd i Vattenfallsmodellen
Many research reports mention the fact that a huge number of all system
development projects never reach a successful ending; with other words never
fulfil formulated goals. By identifying and forming success factors (and in
some aspect risk factors) that the project manager in practice can use, this
study may be seen as a step in the direction towards minimising the high number
of failed system development projects.
The purpose of this research report is to investigate how a system development
project, where the development process is based on a specific development or
process model (in this case the Waterfall model), can and should be driven. I
aim to clarify what is demanded of a project leader for the specific
development process and give an account for which eventual leadership qualities
that can be well suited for given situation in relation to the need for
technical competence.
Among other things the project manager should inspire confidence, drive, be a
decision maker, engage and own some form of basic knowledge in the field of
system development.
Från 2D till BIM i ett trähusföretag : Transition from 2D-CAD to BIM in a timber frame home company
A prefabricated timber frame house previously built by Villafabriken AB has been modeled in Autodesk Revit Architectural, a 3D-program based on BIM-technology. This has been done tosee if it?s possible to produce the publications that Villafabriken demands from the designengineer?s work, and examine which possible extra values that may arise compared to traditional 2D-CAD drawing.BIM is short for Building Information Modeling. Everything is stored in a single database and a change in the project file is automatically updated across the project. BIM provides more than just drawings since information from the model can be retrieved in various ways such as lists and quantity schedules.It was possible to produce the publications that Villafabriken demanded using Revit, but BIM doesn?t only mean a new way of drawing, it also require a change in the company?s process were the information from the model is being used..
Kapacitetsberäkningsmodell för materialhanteringsflödet på Ericsson i Kumla
Ericsson?s factory in Kumla, Modules Kumla, became a hub for radio modules and micro base stations, which enables mobile communication through radio base stations, in 2004. Because of this the factory focuses more on the logistics operations. This has led to a need to be able to plan the capacity for the materials handling system. This master thesis has therefore been performed at Modules Kumla to develop a capacity calculation model for the material handling flow during the autumn of 2005.The work has contained a mapping of the material handling flow regarding to which activities was performed and how much time they consumed.
Välfärd, jämställdhet och demokrati
The purpose of the essay is to analyze the welfare state from a gender perspective. Further, the paper analyzes and critically examines three different normative solutions provided by Irish Marion Young, Nancy Fraser and Jürgen Habermas for the realization of a welfare state that includes women.Habermas argues that the welfare state has created a situation of dependency and state paternalism which reduces both individual and collective self-determination. Young follows Habermas? argument. She argues for a political climate where justice is reduced to the distribution of material goods rather than the elimination of underlying relations of domination and gender specific patterns.
Perfluoroalkyl substances in Arctic birds : a comparison between glaucous gulls and black guillemots from Svalbard
Perfluoroalkyl substances (PFASs) are ubiquitous in the environment today and they have been detected even in remote areas such as the Arctic. PFASs can be transported by the atmosphere and ocean currents but the transport mechanism is not fully understood. PFASs may be harmful to organisms due to their persistence in the environment, bio-accumulation potential and toxicity. Studies have shown that PFASs can cause adverse effects on the metabolism as well as the endocrine- and reproduction systems in organisms. In this study, PFASs were investigated in glaucous gull (Larus hyperboreus) (n=5) and black guillemot (Cepphus grylle) (n=4) from Svalbard.
Bedömning av skada på naturmiljö och rennäring för den föreslagna fjällvägen mellan Borgafjäll och Saxnäs : - Väg- och transportforskningsinstitutets metod för bedömning av skada på bevarandeintressen
Assessment of impacts on nature and reindeer husbandry by the considered mountain road between Borgafjäll and Saxnäs- Swedish National Road and Transport Research Institutes method for assessment of damage to heritage assetsThere are plans regarding the building of a new road from Borgafjäll/Båtas to Saxnäs, and two road alternatives have been presented. The road has been localized to an area which is protected as a nature reserve and listed as a Nature 2000 area. This report aims to determine the effects on the Nature 2000 area and reindeer husbandry, and to be a source of knowledge for future environmental impact assessment in that project. In order to assess the impact on nature values and reindeer husbandry a method from the Swedish National Road and Transport Research Institute (VTI) has been used. A literature review has been made to prescribe the effects and consequences.
Kvarteret Flaggskepparen, Industriellt byggande för offentligt ägda bostäder -En fallstudie i samarbete med NCC Komponent och MKB
The primary focus of this Master thesis is to study how industrial house building can be implemented during production of rental flats under the terms of public procurement. In order to determine a suitable working process as well as presenting a possible architectonic result of the process, a case study is carried through.A housing projekt is designed on a site i Malmö, where the commisioner is MKB Fastighets AB and the contractor is NCC Komponent with the industrial building system NCC Komplett. The focus of the design is to accomplish high quality apartments to a resonable price, as well as solving the overall scheme for the site.The housing projekt, Kv. Flaggskepparen, built on the consept of a single house model, used to handle the entire site, shows that the building system is well suited to accomodate the commisioners demands.In order to reach the best possible architectonic result with the building system, cooperation initiatded in an early stage of the process is neccesary.A model is proposed to handle the situation under the terms of public procurement. The model suggest that the geometrical design is mainly carried out after inquiry and that architectonic qualities should mainly be defined in a non geometrial way for inquiry..
Faktorer som påverkar magnesiumabsorptionen i våmmen hos kor
In metabolism Mg plays an important role because it affects many cellular enzymes in the body. The energy metabolism and protein synthesis are dependent on Mg as an enzyme activator, Mg is also involved in the synthesis of RNA and DNA. Absorption of Mg primarily takes place over the ruminal epithelium in ruminants. The main storage of Mg is in the bones but that can only be reached if the cow is in great need of calcium or phosphorus, it's a hormonal regulated process that induces catabolism of bones. Free and available sources of Mg are found in soft tissues and in the extra cellular fluids that includes cerebrospinal fluids and blood.
Hållfasthetssortering av plankor med hjälp av röntgendata
The aim of this thesis is to find a statistical model that sort logs according to a predicted modulus of elasticity on the sawn boards. The input parameters for the model are X-ray variables from an X-ray scanner. For some of the log classes sawn at the sawmill it is desirable to have a narrow distribution of modulus of elasticity on the sawn boards. 250 pine logs from five different diameter classes were numbered and followed through the sawmill process. Log data were collected from X-ray and 3-D scanners in the log intake.
Biblioteksplanen ? skrivbordsprodukt eller effektivt styrdokument. En intervjuundersökning om inställningen till den kommunala biblioteksplanen vid några grundskolor i Malmö
The aim of this Master?s thesis is to examine how the introducing of municipal library plans has influenced some compulsory schools in Malmö. I wanted to know if the library plan is a possible way to improve the quality of the school library. Through qualitative interviews with four school librarians and four headmasters, I investigate their knowledge of the library plan and their opinion of the possibilities to realize the directions of the plan. The theoretical framework is based on a model of organizational culture by Bakka, Fivelsdal and Lindkvist.