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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

The perception of Nuclear powerin Sweden : How engineering students view it

Abdallah, Ali January 2017 (has links)
Nuclear power has been an important part of the electricity generatingin Sweden in almost half a century. However, the use of nuclear powerraises many complex issues such as economy, accident risks, andradioactive waste management and storage. Nuclear power has thereforebeen debated intensively in Sweden as in many other countries since the1970s. Several countries have changed their nuclear policy and starteddecommissioning programs following the nuclear accident in Fukushimaback in 2011. Citizens' support for nuclear power has declined worldwidein last few years, including in Sweden. This study aims to investigatethe perception of nuclear power among engineering students and showsthat the majority of engineering students, who generally are positivetowards technology, have been affected by their surrounding and areagainst nuclear power. Engineering students in general, both supportersand opponents of nuclear power, agree that Sweden should gradually phaseout nuclear power and replace it by renewable energy sources.
112

Competitive evaluation method of antibodies

Råsander, Mattias January 2020 (has links)
No description available.
113

Environmental adjustments of the mobile preschools in Uppsala

Jernlund, Anna, Pedersen, Niklas January 2017 (has links)
The mobile preschools of Uppsala are buses that are provided as a complement for stationary preschools. The buses are connected to one stationary preschool that provides the necessities such as food and a place for the children to be before and after the daily trips. In Uppsala, there are five mobile preschool buses and they have been operated since 2009. For the bus to provide heat, warm food and energy for activities on the bus, there is a generator installed that runs on biodiesel. The emissions from the generator, in combination with the loud noises that it emits, are of concern for both the children and educators on the bus as well as the people around it. This has caused for alternative ways to deliver electricity to the bus. This study examines three scenarios for delivering electricity and tries to evaluate what the best option could be from different Points of view. The three scenarios are replacing the generator with either a battery, replacing the generator with electricity poles and to replace the generator with a more efficient and quieter one. When evaluating the different scenarios from an economical point of view, the study found that the electricity poles would be the best option. When evaluating the best option with respect to the children and educators, the study found that the battery would be the best option. The negative consequences for continuing to use a generator to supply electricity would be a health hazard for the children and a limitation for the educators in the freedom of choosing location for the bus to visit.
114

Managing Platform-Mediated Ecosystems : Investigating ecosystem interdependencies and strategic choices

Cenamor, Javier January 2015 (has links)
The rapid and ubiquitous spread of information technologies (IT) is creating unprecedented effects that challenge traditional fundamentals of the business world. Platform-mediated ecosystems are increasingly attracting the attention of practitioners from diverse industries, from telecommunications to video consoles, as well as academics from different fields ranging from management to economics, and information systems (IS) and innovation management. A platform-mediated ecosystem can be defined broadly as an industrial architecture with an infrastructure in the center that facilitates value co-creation among different agents (platform owners, and providers and users of complementary products) and a set of rules governing their interdependencies. The speed and the magnitude at which platforms diffuse are inspiring numerous analyses from diverse perspectives, mainly focused on drivers of success and ecosystem interdependencies in different contexts. This thesis highlights the importance of detangling the different interdependencies within platform-mediated ecosystems, while building a comprehensive approach based on the ecosystem as a whole. The wide range of platform types and their rapid evolution makes it difficult to establish a consensual categorization of platforms. A common aspect among most of them is that platform-mediated ecosystems usually present network effects that is the value of products depend on the number of peers within the ecosystem. In this sense, the number of adopters, known also as the size of the installed base, in a market has traditionally had a central importance in the literature. The platform-mediated ecosystems, however, are becoming more and more complex due to rising competition. Thus, there is a need for advancing understanding of the fundamentals of platform-mediated ecosystems and the management alternatives inherent in designing such systems which would enable a comprehensive platform approach to be built. Consequently, the main purpose of this thesis is to advance the understanding of the strategic management of platform-mediated ecosystems. Specifically, this thesis aims to unravel the ecosystem interdependencies and to identify strategic choices as a source of competitive advantage. To achieve this aim, different methodologies are applied in this thesis. Specifically, Paper I was based on a structured literature review of relevant papers in platform-mediated ecosystems for the period 2000 through 2014. The empirical analyses conducted in Papers II, III, and IV use different secondary samples from the video console ecosystem. Finally, the results in Paper V were based on a qualitative, multiple case study of global manufacturing firms implementing product-service systems (PSS) through a platform architecture. Overall, the findings within this thesis present the following main theoretical contributions. First, the thesis presents a comprehensive approach toward platform mediated ecosystems covering new ways of value creation and value capture, new governance regimes, and new agents making interdependent choices. Precisely, platform ecosystems offer unprecedented efficiencies and innovation enhancements, and the possibility of establishing rules for new role participation and interaction. Thus, the findings shed light on the fundamentals and future trends in the platform approach. Second, different ecosystem interdependencies may increase the platform adoption and performance. Specifically, the thesis highlights the importance of the positive effects from different agents in the complementary product markets. Accordingly, the findings contribute on unraveling the interdependencies within platform ecosystems. Third, platform performance can be enhanced by exploiting complementarities among strategies and regions. Precisely, the findings show significant complementarities from the joint management of different activities related to the complementary products and the platform, and from the presence in several countries. Consequently, the findings provide strategic choices as a source of competitive advantage. Finally, transformation toward global PSS may be guided by a platform approach, which may be helpful to explain the origins in building a platform ecosystem. In this respect, the findings shed light on how platform-mediated ecosystems are created. In sum, these findings have important implications for researchers in strategic management, economics, and information systems as well as managers from highly innovative industries and traditional sectors under structural transformation. This thesis concludes with the limitations that should be considered when interpreting the findings and some suggestions for future researchers. / Godkänd; 2015; 20150917 (javcen); Nedanstående person kommer att disputera för avläggande av teknologie doktorsexamen. Namn: Javier Cenamor Gómez Ämne: Entreprenörskap och innovation/Entrepreneurship and Innovation Avhandling: Managing Platform-Mediated Ecosystems: Investigating Ecosystem Interdependencies and strategic Choises Opponent: Biträdande professor Andreas Larsson, Institutionen för maskinteknik, Blekinge tekniska högskola, Karlskrona. Ordförande: Biträdande professor Vinit Parida, Avd för innovation och design, Institutionen för ekonomi, teknik och samhälle, Luleå tekniska universitet, Luleå. Tid: Tisdag 10 november, 2015 kl 13.00
115

Bordningssäkerhet : En studie om lotsars och båtmäns upplevelser vid bordningsmomentet

Engström, Alf, Fröberg, Daniel January 2017 (has links)
Abstrakt   När ett fartyg ska anlöpa eller avgå en hamn måste det vanligtvis anlita en lots som kommer ombord för att vägleda fartyget. I Sverige genomförs ungefär 33 000 lotsningar varje år och vid majoriteten av dessa har lotsen kommit ombord fartyget genom att klättra på en lotslejdare som riggas utmed fartygssidan. Studien genomfördes i syfte att undersöka de riskfaktorer som påverkar säkerheten för lotsar och båtmän under bordningsmomentet. Studien genomfördes med en kvalitativ ansats i form av halvstrukturerade intervjuer. Resultatet visar att svenska lotsar och båtmän upplever bordningsmomentet som riskfyllt, framförallt vid sämre väderförhållanden. Lotsarna och båtmännen upplever att det är mer riskabelt för lotsen att debarkera än att embarkera eftersom lotsen har svårare att hålla koll på sin omgivning vid detta moment. Resultatet visar också att fler fartyg behöver bli bättre på att följa de riktlinjer som finns gällande bordningsarrangemang för att bordningsmomentet ska upplevas säkert bland lotsar och båtmän. / Abstract   When a vessel is to enter or leave a port, it usually needs to hire a pilot to guide the vessel. In Sweden approximately 33,000 pilotages are carried out every year, in the majority of these the pilots have boarded the ship by climbing on a pilot-ladder which have been rigged alongside the vessel's side. The study was conducted to investigate the risk factors that affect the safety of pilots and boatmen during the pilot transfer. The study was conducted with a qualitative approach in interview format. Interviews were conducted using an interview template based from previous literature in the subject. The study has been limited to Swedish pilots and boatmen. In the study, ten pilots and four boatmen participated in three Swedish pilot stations, which mainly handle different ship types and vessel sizes. In the study, the result shows that Swedish pilots and boatmen experience the pilot transfer operation as risky, especially in poorer weather conditions. The pilots and boatmen find it more risky for the pilot to disembark than to embark a vessel, as the pilots have more difficulty keeping track of their surroundings during this moment. The study shows that more vessels need to establish the international guidelines concerning pilot transfers and boarding arrangements, to ensure safe pilot transfers.
116

Artificiell intelligens som beslutsmetod

Frideros, Micael January 2017 (has links)
Detta arbete behandlar artificiell intelligens som beslutsmetod. Efter inledande diskussioner om de övergripande skillnaderna mellan hjärnans och datorns funktionssätt, olika utvecklingsinriktningar av artificiell intelligens samt olika metoder för att skapa artificiell intelligens identifieras strategier för hur artificiell intelligens kan användas som beslutsmetod beroende på faktorer som transparens, effektivitet samt mängden tillgänglig testdata. Exempelvis identifieras några typiska beslutssituationer där det kan antas att automatiserat beslutsfattande baserat på artificiell intelligens har stor potential, samt situationer då metoden kan antas vara mindre lämplig. Därefter analyseras teknikutvecklingen inom artificiell intelligens, både generellt och inom fyra specifika tillämpningsområden: inom autonoma fordon, inom finans, inom medicin och inom militären. Både den övergripande undersökningen av den generella teknikutvecklingen och studien av de fyra teknikområdena indikerar fortsatt mycket snabb utveckling inom området. Exempelvis visar en analys av patentdatabasen Espacenet att antalet patent inom området utvecklas i det närmaste exponentiellt. Samtidigt har det på senare tid gjorts flera tekniska genombrott, t.ex. utvecklandet av allt effektivare algoritmer genom användandet av hierarkiska strukturer med flera olika nivåer av ickelinjär informationsbearbetning, något som ofta benämns Deep Learning. Ett exempel är den metod för artificiell intelligens som utvecklas av DeepMind, som visat sig vara tillämpningsbar inom många olika områden, från att spela klassiska datorspel som Space Invaders och Breakout på en övermänsklig nivå till att göra betydande effektiviseringar i driften av Googles datorhallar. Även ur ett hårdvaruperspektiv är utvecklingen närmast exponentiell, driven av kontinuerliga framsteg inom tillverkningsprocesser samtidigt som det nyligen gjorts betydande framsteg med specialiserade kretsar för artificiell intelligens, något som sannolikt kommer att resultera i ännu snabbare utveckling av kraftfullare artificiell intelligens inom en nära framtid. Med hänsyn till teknikens effektivitet och den mycket snabba utvecklingen inom området diskuteras även några specifika frågeställningar som ofta nämns i diskussionen om artificiell intelligens, dess påverkan på arbetsmarknaden och den globala säkerhetsbalansen, för att baserat på detta sedan diskutera artificiell intelligens som beslutsmetod även i ett vidare perspektiv.
117

Decision and Policy Making in the European Union : Role of EU Agencies in the decision and policy making in the area of chemicals and food safety

Fallström Mujkić, Pia-Johanna January 2019 (has links)
EU regulations, decisions and policy making are matters that concern every resident in the EU and risk and benefit assessment and analysis form part of the EU decision and policy making. This thesis discusses the decision/policy making in the EU and the risk assessment activities of the European Food Safety Authority (EFSA) and the European Chemicals Agency (ECHA), as well as ECHA’s socio-economic analysis activities. It also studies the role of the European Commission and the Comitology process. The EU regulates what chemicals or food stuffs/ingredients, for instance additives, may be made available in the European market. How the decisions are made about what is allowed and what not, and who makes those decisions, is not necessarily evident due to the complexity of the processes. In this thesis the decision making at different stages of the EU regulatory processes has been identified and analysed in order to find out by whom and how the decisions are made. The method used was a literature search with an overview of the existing theories and research from the areas of EU decision making, risk assessment and risk management. The regulatory processes were studied from a decision making perspective with the aim to identify and record possible decision making opportunities of different actors beyond the European Commission. The decision making opportunities were classified and organised based on their level of impact to the processes. Two real cases were studied: the restriction of lead in jewellery under REACH Annex XV restrictions and the authorisation of ammonium chloride in food under Flavourings regulation. Decision making opportunities and methods were looked for in those processes. It was found that while, in the studied cases, there appeared possibilities to ensure science based good regulatory decision/policy making, it remained uncertain and possibly politicised. It was also revealed that in certain steps the processes lacked transparency.
118

Asset Management of Railway Tracks Using Stochastic Petri Nets

Kumari, Jaya January 2019 (has links)
Railways are one of the most important transport systems. It is crucial to have a rail network that is safe, reliable and available. Asset Management for railways involves the optimization of the maintenance activities based on asset condition, life cycle cost and availability of equipment. Irregularities in the track cause the wear of rail resulting in passenger discomfort, speed restrictions and line closures. The track is inspected for these irregularities and corrected using a tamping vehicle. The degradation behavior of the track can be modelled to predict the future degradation. This prediction forms the basis of the maintenance planning based on the expected track condition. A petri net model can be used to simulate the track degradation, inspection and maintenance process over a period of 20 years, and the outputs of the model are used for LCC analysis. Further, the cost is optimized with the safety risk to suggest maintenance threshold levels and Inspection Interval. The proposed methodology will assist the maintenance decision system for Asset Management of Railway track, which is strategic and cost effective. This methodology is demonstrated using a case study of a Line 414 in Sweden, by modelling the track behavior with Standard Deviation of Longitudinal Level. It can be further expanded and adapted for maintenance planning for similar assets within railways.
119

Cooling Air Management For Hybrid Electric Vehicles Using Combined 3D Aerodynamic & Thermodynamic CFD : For External Automotive Aerodynamics

Haglöf, Jesper January 2019 (has links)
This is a master thesis report in vehicle aerodynamics and cooling air management. The thesis is carried out at China Euro Vehicle Technology (CEVT) AB and is part of the course P7010T, Master Thesis in Space Engineering at Luleå University of Technology (LTU). The thesis has been supervised by Mattias Olander at CEVT and Gunnar Hellström at LTU and was done over 20 weeks during the spring semester of 2019. As the vehicle industry moves from mostly using combustion engines to hybrid and electric power systems the importance of decreasing cooling air drag has increased. Cooling air drag can be around 5-15% of the total drag, and a lot of research has been done over the years on how to decrease it. Cooling drag is defined as the force acting in x-direction from the cooling air flowing through the engine bay. The air is let in through the grilles to cool down the engine and escapes through different outtakes usually below the vehicle and through the wheelhouse. The air loses a lot of energy inside the engine bay as well as it changes in temperature. In this study a method has been developed to include the energy equation in the aerodynamic computational fluid dynamics (CFD) simulation. Research has also been done on which design parameters that affect the cooling air drag and how air ducts could be designed to better transport the flow to and from the radiators without loosing to much in energy. In the first part of this study a method was developed to solve the vehicle aerodynamics with energy equation included. All method development and design parameter tests weredone on the Sport Utility Vehicle (SUV) A model, which is a CEVT concept car. The model was first implemented on a simple symmetric model and then on a full model. It was tested both with a normal steady state solution and a pseudo transient solutions. The pseudo transient solution proved to solve for a faster convergence, although both methods worked well. Therefore the design parameter testing was chosen to be done with the pseudo transient solver.The design parameter testing was done in two steps, first opening and closing different outlets and then trying to implement different cooling air ducts. The first study showed that air through the wheelhouses increases the drag as well as having air entering only inthe upper grille and travelling down through floor and wheelhouse. In the second study,the area between the grilles and cooling package was sealed and inlet ducts were created to control the flow from the grilles to the cooling package. When just adding inlet ducts, the mass flow through the grilles was decreased, but the mass flow through the cooling package was increased due to less separation of the air, which lead to a drag reduction of 0.2%. Other design implementations was to reshape the wheelhouse outlets, therefore a wheelhouse outlet duct was designed. The ducts purpose was to lead the air out of the wheelhouse and behind the tire and exit the vehicle parallel to the free stream flow. The wheelhouse duct is most effective and decreases the drag force by 0.7%. An air duct was also designed to lead the flow after the cooling package fan to the outlets. The ducts purpose was to prevent the air from loosing in energy when rising to the roof of the engine bay, the duct compresses the air and leads it efficiently over the engine with a drag force decrease on 0.3%. The inlet duct, wheelhouse duct and after fan duct was all put together to a thesis design. Due to the higher mass flow through the cooling package the upper grille could be sealed by 9.9% and still allow the same mass flow through the cooling package as for the SUV A. The thesis design for improved cooling air management allowed a decrease of drag force timesarea by 0.9%. In conclusion there is much that can be done to improve the cooling air drag. It is most favorable to have a sealed volume with inlet air ducts before the cooling package, have outtakes aligned with the free stream flow, minimize cooling air to escape through the wheelhouse outlets and to minimize the height of the engine bay as much as possible.
120

SUGGESTIONS TO CONSIDER WHEN ENGAGING IN THE PROCESS OF DEVELOPING A SYSTEM DYNAMICS MODEL FOR FREQUENT ATTENDERS IN HEALTHCARE

Birtic, Martin January 2019 (has links)
Healthcare systems face many challenges that prevent them from reaching their full potential. Overcoming these challenges can be very difficult in part because of their complexity. Predicting all the possible effects that improvement attempts may create is difficult and high-quality decision support material is difficult to obtain. System dynamics modeling and simulation is a technology that has been applied for some time within the healthcare domain in order to assist the decision-making process. This technology has gained increased interest in the domain over the past decade. This project analyses the application of system dynamics modeling to a specific problem in the healthcare sector, namely that of frequent attenders to the emergency department. A literature review is performed to extract suggestions that could be considered when engaged in the process of developing a system dynamics model for managing frequent attenders in healthcare. It has been found that the research on frequent attenders and their management is very heterogeneous and ambiguous making it difficult to draw strong conclusions about the effectiveness of different management strategies. Model builders are forced to turn to other sources for model data. It is also found that system dynamics modeling of frequent attenders has not yet been done. This situation led to the expansion of the search scope to include related modeling research as the basis for suggestion extraction. 65 suggestions are extracted into three broad categories with the limitation of not being strictly specific to the modeling of frequent attenders, but have a more general nature. And although their value is not evaluated, it is hoped that they could contribute as inspiration to certain system dynamics model development endeavors.

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