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117 Uppsatser om Mechanism - Sida 6 av 8

Utveckling av en Multi-Zonsmodell för NOx Bildning i Diesel Motorer

This thesis work is the last part of the Master of Science education inmechanical engineering at KTH, Stockholm.The aim of this project was the development of a Multi-zone modelfor NOxformation in Diesel engines. Because of the stringent emissionlegislations, great effort is made to decrease the fuel consumption and theharmful emissions of internal combustion engines. Computer simulationsplay a decisive role in this context because they substitute the expensiveand time-consuming laboratory tests.The model is based on a multi-zone approach and uses the wellknownExtended Zeldovich Mechanism which gives a relation to calculatethe NO formation rate using the concentration of different gas speciesinvolved in the process.All the most important phenomena involved in the Diesel combustionhave been modelled. A special attention is then paid to the equilibriumconcentration calculation; this is a significant part of the model whichstrongly influences the following steps.A Simulink model has also been developed. This second version isbased on the previous model and it is made especially to allow theconnection with other external softwares, GT-power in this case.

Expression av PSI-N från Arabidopsis thaliana i E.coli

PSI-N is one of the subunits in eukaryotic Photosystem I (PSI) and is located on the lumenal side of the thylakoid membrane. It is known to interact in the electron transport chain between plastocyanin and PSI, but the Mechanism behind the interaction is still unclear. To achieve a better understanding of PSI-N´s role in the photosynthesis it is necessary to develop a method for purification of PSI-N. The goal with this project was to design a plasmid that encodes a fusion protein containing PSI-N. With use of proteases the fusion protein can be cleaved into purified PSI-N.

Expression av PSI-N från Arabidopsis thaliana i E : coli

PSI-N is one of the subunits in eukaryotic Photosystem I (PSI) and is located on the lumenal side of the thylakoid membrane. It is known to interact in the electron transport chain between plastocyanin and PSI, but the Mechanism behind the interaction is still unclear. To achieve a better understanding of PSI-N´s role in the photosynthesis it is necessary to develop a method for purification of PSI-N. The goal with this project was to design a plasmid that encodes a fusion protein containing PSI-N. With use of proteases the fusion protein can be cleaved into purified PSI-N.

Effekter av fysisk aktivitet på psykisk ohälsa hos unga kvinnor

Among young adults and especially women, psychological issues are common phenomena in the society such as depression, anxiety and stress. Research has shown that physical activity can be a complement for anti-depressant medication. The aim of this review is to examine previous research to find out how physical activity can provide positive effects on overall mood state in particular young women's psychological health. The results of this review is that there are support in the literature of young women that physical activity may enhance mood in studies of depression and anxiety symptoms and small support for the effects on reducing stress. Physical activity with both high intensity and low intensity has shown to have positive effects on depression and anxiety, but the physical activity has to be regular for long-term effects.

Poly - bejakandet av samtidigt begär och samtidig kärlek. : En genusvetenskaplig intervjustudie om att (vilja) ha flera kärleksfulla intima relationer samtidigt.

Poly, to live in several loving and intimate relationships at the same time, is one alternative to the mono norm. In Sweden polygamy is illegal yet in recent years poly has slowly started to enter the hetero normative political agenda and raise debate in the media. But what does poly mean, and how do those who identify with this type of relationship describe it in contrast to mono? The theoretical framework is based on a structural viewpoint of the changes in the organisation of the family and the growing de-traditionalism of society. Amongst other I use a Foucauldian perspective to explain the structural shift (yet not replacement) between an Alliance pattern and a Sexuality pattern.

Visualizing Innovation Capital: A Case study of Technology Transfer and Biomedical start-up

Purpose: The purpose is to present a greater understanding of the progression of innovation capital in a technology transfer and biotech start-up context. The findings offer technology transfer professionals, entrepreneurs and academia an overall perception and mental framework of the technology transfer practice and the embracement of a promising invention, building upon its hidden value. Methodology: The thesis was conducted using a qualitative case study, executed with the help of interviews, in order to answer the research question: How is an embryo of innovation capital continuously cultivated in a technology transfer and biomedical start-up process? Conclusions: A technology transfer entity provides the means to establish a platform where an entrepreneur can build its own human capital, structural capital, and relationship capital. The forms of capital interact and thus create value, herein considered as innovation capital.

Kinematisk och dynamisk modellering av den haptiska enheten TAU i sex frihetsgrader

The thesis presents an optimally designed kinematic structure for a new 6-DOF haptic devicebased on TAU configuration. The configuration of the TAU-2 proposed by Suleman Khan andKjell Andersson [1] was modified and its mobility was verified by using Grübler criterion tohave a 6 DOF. Analytical kinematic models for the inverse and forward kinematics weredeveloped for the haptic TAU configuration to determine a set of optimal design parameters.Kinematic performance indices such as volume of the workspace, kinematic isotropy and payload index, were defined based on the singular values of the Jacobian matrix. The Jacobianmatrix was scaled to homogenize the physical units. The Jacobian matrix dependent on theposition and orientation of the end-effector gives local isotropy and pay load index, so globaldesign indices were defined, which represent the performance of the Mechanism in the wholeworkspace.

Ledinflammationer på häst och intraartikulär behandling med hyaluronsyra : en pilotstudie på hyaluronsyra X

Traumatic arthritis is a common cause of lameness in horses. One of different treatment alternatives of arthritis, is intra-articular injection with hyaluronan. As knowledge about pathophysiology of arthritis and function of hyaluronan is increasing, understanding grows about the Mechanism of hyaluronan action in joints. Hyaluronan has, in addition to effects on viscosity, anti-inflammatory and analgesic effects. Extensive research and scientific studies have been made on exogenous hyaluronan.

Adaptive QoS Management in Dynamically Reconfigurable Real-Time Databases

During the last years the need for real-time database services has increased due to the growing number of data-intensive applications needing to enforce real-time constraints. The COMponent-based Embedded real-Time database (COMET) is a real-time database developed to meet these demands. COMET is developed using the AspeCtual COmponent-based Real-time system Development (ACCORD) design method, and consists of a number of components and aspects, which can be composed into a number of different configurations depending on system demands, e.g., Quality of Service (QoS) management can be used in unpredictable environments. In embedded systems with requirementson high up-time it may not be possible to temporarily shut down the system for reconfiguration. Instead it is desirable to enable dynamic reconfiguration of the system, exchanging components during run-time.

Phycoremediation of pesticides using microalgae

Every year, pesticides are found in surface and ground waters in Sweden. Fungicides are in common usage and applied in high amounts against potato late blight. The present thesis examined the possible removal of four fungicides (metalaxyl, cyprodinil, propamocarb and mandipropamid) from water using the microalgae Chlorella vulgaris. Microorganisms are capable of decomposing a range of organic pollutants and the main focus in previously published studies has been on bacteria and fungi. Microalgae are mostly studied due to their high capacity in biosorbing heavy metals.

Hur påverkar inavel fruktsamheten hos häst?

Inbreeding has become a problem in some horse breeds. Studies show that it may lead to inbreeding depression which affects e.g. reproduction traits. In the wild there are Mechanisms that make horses avoid mating with close relatives. When selection is done by humans this Mechanism is removed and intensive breeding for a few traits, for example good racing results, can become a problem.

Socialsekreterares syn på bemötandet och relationen med klienter - en jämförande studie av försörjningsstöd och missbrukarvård

Our aim with this study is to explore socialworkers perception of what is a good treatment is and how to establish good relationship with their clients. We have decided to limit our study with social workers in Economic assistance and Abuse Units in social servises and explore if we can discern any differences between the units. We have chosen to use qualitative methods to achieve the aim of this study. We interviewed a total of seven social workers, of which three were from Abuse unit and four were from Economic assistance unit. One of the theoretical frame we have used is Goffmans (1970, 1974) theories about social interaction in which he explains the social encounter between social workers and clients.

Förnuft till döds? Debatten om Georg Henrik von Wrights bok: Vetenskapen och förnuftet

This paper relates a debate on a book Vetenskapen och förnuftet (1986) written by the Scandinavian philosopher Georg Henrik von Wright (1916 - 2003). The book brings up fate of mankind, raising the question if human rational thinking and scientific achievements are threatening our very existence on earth. Shortly after the book was published, it was intensively debated in a leading Swedish newspaper Svenska Dagbladet. Some 20 leading politicians and scientists contributed with their criticism during spring 1987. The paper highlights this debate by writing reception history, describing how the book with its serious message was received by leading scientists of the time.

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.

Webbsystem för matprisjämförelser

This is a thesis project in the field of information technology which begins by evaluating existing food price comparison systems and subsequently aims to design an improved, web based system for said purpose. The system features interfaces for price reporting, price comparisons as well as various search and review functions. The objective is to create a system able to compete with existing price comparison systems, which requires careful selection of products that can be found in all foodstores that also represent different households; a user-friendly price reporting and price comparison interface and an efficient tool for ensuring the validity of reported prices.The designed system features a more accurate formula for calculating average prices in events where the real price is missing; a more reliable security Mechanism forv alidation of reported prices and a more comprehensible interface for viewing price reports, reporting prices, reviewing stores and products in comparison with existing systems. The system does, however, suffer from some optimization issues primarily in the form of inefficient database modeling; SQL queries and JavaScript code although testing has shown that these shortcomings do not hamper overall performance to such a degree that usability is compromised. Further usability testing performed on the system with five test subjects shows that a high level of overall user-friendliness has been achieved even though some special features, such as the detailed report containing price information per product for each store need to be improved.It is not possible to say at this time whether or not the designed system will be able to compete with existing ones or if the very concept of food price comparisons per se is viable in terms of profitability and marketability.

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