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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.
441

Multinationella koncerners internprissättningspolicies

Häggström, Olle, Grönqvist, Johan January 2006 (has links)
<p>Syfte:</p><p>- Att undersöka om OECD:s riktlinjer är vedertagna hos de granskade koncernerna och beskriva vilka internprissättningsmodeller de använder sig av.</p><p>- Att beskriva vilka effekter de undersökta koncernerna försöker uppnå med sin internprissättning.</p><p>- Att undersöka vilken vikt skatteaspekten har för dessa koncerner vid sin internprissättning.</p><p>- Att undersöka hur dessa koncerner dokumenterar sin interprissättning och vilka påföljder de nya dokumentationskraven kommer att få för dem.</p> / <p>Purpose:</p><p>- To examine whether OECD:s guidelines are accepted among the reviewed multinational corporations and to describe what Transfer Pricing models they use.</p><p>- To describe what kind of effects they try to accomplish with their Transfer Pricing.</p><p>- To examine to what degree the tax issue has on Transfer Pricing.</p><p>- To examine how these Multinational Corporations document their Transfer Pricing and how the new demands on documentation will affect them</p>
442

Ru(II) under illumination : A study of charge and energy transfer elementary processes / Les complexes de Ru(II) sous illumination: Etude des processus élémentaires de transferts de charges et d’énergie

Herman, Leslie C.V. 11 December 2008 (has links)
Une compréhension sans cesse plus pointue des processus élémentaires de transferts de charges et d’énergie, qui sont à la base même de nombreux processus biologiques, permet non seulement l’élaboration mais aussi l’amélioration de la mise au point de molécules photoactives utiles dans différentes applications. C'est le cas (i) de systèmes moléculaires et supramoléculaires destinés à mimer efficacement la photosynthèse, ou encore (ii) de molécules photoactives capables d’interagir avec des macromolécules biologiques et d’induire une transformation de ces biomolécules. C’est dans ce cadre général que s’inscrit l’élaboration de nouveaux complexes polyazaaromatiques de Ru(II) capables d’interagir avec la double hélice d’ADN et de photoréagir avec sa base la plus réductrice, la guanine, par transfert d’électron photoinduit. C’est sur la base de ces processus que des nouveaux agents antitumoraux photoactivables ont pu être développés. L’utilisation de complexes de Ru(II) dans le design d’entités supramoléculaires polymétalliques destinées à jouer le rôle de collecteurs de lumière et permettant ainsi de mimer les systèmes d’antennes naturels s’intègre également dans cette démarche. L’ensemble de notre travail s’est concentré sur ces deux domaines d’applications. Par l’étude de différents processus de transfert de charges/d’énergie au sein des complexes seuls (processus intramoléculaires) ou en interaction avec un environnement spécifique (processus intermoléculaires), nous avons souhaité mettre en évidence l’intérêt de l’utilisation d’un nouveau ligand plan étendu, le tpac, au sein de complexes du Ru(II). Un tel ligand permet en effet de conférer d’une part une affinité élevée des complexes résultants pour l’ADN, et d’autre part, de par sa nature pontante, de connecter des unités métalliques entre elles au sein d’entités supramoléculaires de taille importante. Les propriétés photophysiques de quatre complexes basés sur le ligand plan étendu tpac, le [Ru(phen)2tpac]2+ (P) et son homologue dinucléaire le [(phen)2Ru tpac Ru(phen)2]4+ (PP) (à base de ligands ancillaires phen), ainsi que le [Ru(tap)2tpac]2+ (T) et son homologue dinucléaire le [(tap)2Ru tpac Ru(tap)2]4+ (TT) (à base de ligands ancillaires tap), ont été étudiées et comparées entre elles. L’examen de ces propriétés, d’abord pour les complexes seuls en solution, en parallèle avec celles de complexes dinucléaires contenant un ligand pontant PHEHAT, a permis de mettre en évidence l’importance de la nature du ligand pontant utilisé. Ces résultats ont ainsi révélé qu’un choix judicieux du ligand pontant permet de construire des entités de grande taille capables de transférer l’énergie lumineuse vers un centre (cas du ligand PHEHAT), ou, au contraire, de relier entre elles des entités ne s’influençant pas l’une l’autre d’un point de vue photophysique (cas du ligand tpac). Les propriétés des complexes du tpac, étudiés cette fois en présence de matériel génétique (mononucléotide GMP, ADN ou polynucléotides synthétiques), se sont révélées très différentes selon que le complexe portait des ligands ancillaires phen (P, PP) ou tap (T, TT). Seuls les complexes à base de tap sont en effet photoréactifs envers les résidus guanine. Nous avons dès lors focalisé cette partie de notre travail sur les deux complexes T et TT. Cette photoréaction, ainsi que le transfert d’électron photoinduit entre ces complexes excités et la guanine, ont pu être mis en évidence par différentes techniques de spectroscopie d’émission tant stationnaire que résolue dans le temps, ainsi que par des mesures d’absorption transitoire dans des échelles de temps de la nano à la femto/picoseconde. L’étude du comportement photophysique des complexes en fonction du pH a en outre révélé de manière très intéressante que, pour des études en présence d’ADN, la protonation des états excités des complexes devait être considérée. Les résultats de cette étude nous ont fourni des pistes quant à l’attribution des processus observés en absorption transitoire. Le transfert d’électron a également fait l’objet d’une étude par des méthodes théoriques. Ces calculs ab initio ont permis de mettre en évidence une faible influence de l’énergie de réorganisation sur la vitesse de transfert d’électron, qui semble dépendre plus sensiblement de la non-adiabaticité du processus, mais surtout de l’énergie libre de la réaction et d’un éventuel couplage à un transfert de proton. L’ensemble des résultats obtenus avec les complexes T et TT en présence de matériel génétique, qui, de manière assez inattendue, sont très semblables, indiquent que ces complexes présentent tous deux un grand intérêt pour le développement de nouvelles drogues antitumorales photoactivables.
443

Multinationella koncerners internprissättningspolicies

Häggström, Olle, Grönqvist, Johan January 2006 (has links)
Syfte: - Att undersöka om OECD:s riktlinjer är vedertagna hos de granskade koncernerna och beskriva vilka internprissättningsmodeller de använder sig av. - Att beskriva vilka effekter de undersökta koncernerna försöker uppnå med sin internprissättning. - Att undersöka vilken vikt skatteaspekten har för dessa koncerner vid sin internprissättning. - Att undersöka hur dessa koncerner dokumenterar sin interprissättning och vilka påföljder de nya dokumentationskraven kommer att få för dem. / Purpose: - To examine whether OECD:s guidelines are accepted among the reviewed multinational corporations and to describe what Transfer Pricing models they use. - To describe what kind of effects they try to accomplish with their Transfer Pricing. - To examine to what degree the tax issue has on Transfer Pricing. - To examine how these Multinational Corporations document their Transfer Pricing and how the new demands on documentation will affect them
444

Effects of Temperature on the Kinetic Isotope Effects for Proton and Hydride Transfers in the Active Site Variant of Choline Oxidase Ser101Ala

Uluisik, Rizvan C 23 May 2013 (has links)
Choline oxidase catalyzes the oxidation of choline to glycine betaine. The reaction includes betaine aldehyde as an intermediate. FAD is reduced by the alcohol substrate, betaine aldehyde intermediate and oxidized by molecular oxygen to give hydrogen peroxide. In this study, the Ser101Ala variant of choline oxidase was prepared to elucidate the contribution of the hydroxyl group of Ser101 in the proton and hydride transfer reactions for proper preorganization and reorganization of the active site towards quantum mechanical tunneling. The thermodynamic parameters associated with the enzyme-catalyzed OH and CH bond cleavages and the temperature dependence of the associated solvent and substrate kinetic isotope effects were investigated using a stopped-flow spectrophotometer. The proton and hydride transfer have been shown to be occurring via quantum tunneling in CHO-S101A enzyme.
445

Heat and mass transfer analogy under turbulent conditions of frying

Farinu, Adefemi 20 November 2006
Sweetpotato (<i>Ipomoea batatas</i>) is a popular vegetable across the world. It is a staple food item of many countries in South America, Africa and Asia where the population depends on the crop as an important source of energy and essential nutrients like vitamins A and C, calcium, iron and copper. It is also a very popular crop in North America. Deep fat frying is one of the favourite processing methods for sweetpotato. The method is fast and the finished product is desired for its unique flavour and taste. <p>The main objective of this study was to establish analogy between convective heat and mass transfer during frying. The accurate estimation of the coefficients for both phenomena is challenging. During frying, the rate of heat transfer from the oil to the food surface is largely controlled by the convective heat transfer coefficient. This heat transfer coefficient is dependent on the interaction between the temperature gradient and the drying rate in a frying process. The temperature gradient and the drying rate in turn partly depend on the thermophysical properties of the product. In this study, thermophysical properties of sweetpotato were studied and modeled as a function of moisture content and temperature. The properties of interest are specific heat capacity, thermal conductivity, thermal diffusivity and density. A designed deep fat frying experiment of sweetpotato was carried out under four different oil temperatures (150, 160, 170 and 180°C) and using three different sample sizes (defined as ratio of diameter to thickness (D/L: 2.5, 3.5 and 4.0). Convective heat transfer coefficients under these frying conditions were estimated and computer simulation based on finite element modeling technique was used to determine convective mass transfer coefficients. Correlation between heat transfer coefficient and mass transfer coefficient were investigated with reliable statistical tool. Effects of sample size, oil temperature and frying time on heat and mass transfer were also studied. <p>Specific heat, thermal conductivity and thermal diffusivity of sweetpotato were all found to increase with increase in temperature and moisture content. Density decreased with increase in moisture content. Maximum heat transfer coefficient reached during sweetpotato frying was in the range of 700-850 W/m2.°C. Heat transfer coefficient of sample during frying increased with increase in frying oil temperature but decreased with increase in sample size. Same trend for heat transfer coefficient was observed for effects of oil temperature and sample size on mass transfer coefficient. Maximum mass transfer coefficient reached during sweetpotato frying was in the range of 4×10-6 to 7.2×10-6 kg/m2.s. No general relationship was established between heat transfer coefficient and mass transfer coefficient during frying but a relationship was established between maximum heat transfer coefficient and maximum mass transfer coefficient. A trend was also observed between maximum heat transfer coefficient and the corresponding mass transfer coefficient at that point.
446

Heat and mass transfer analogy under turbulent conditions of frying

Farinu, Adefemi 20 November 2006 (has links)
Sweetpotato (<i>Ipomoea batatas</i>) is a popular vegetable across the world. It is a staple food item of many countries in South America, Africa and Asia where the population depends on the crop as an important source of energy and essential nutrients like vitamins A and C, calcium, iron and copper. It is also a very popular crop in North America. Deep fat frying is one of the favourite processing methods for sweetpotato. The method is fast and the finished product is desired for its unique flavour and taste. <p>The main objective of this study was to establish analogy between convective heat and mass transfer during frying. The accurate estimation of the coefficients for both phenomena is challenging. During frying, the rate of heat transfer from the oil to the food surface is largely controlled by the convective heat transfer coefficient. This heat transfer coefficient is dependent on the interaction between the temperature gradient and the drying rate in a frying process. The temperature gradient and the drying rate in turn partly depend on the thermophysical properties of the product. In this study, thermophysical properties of sweetpotato were studied and modeled as a function of moisture content and temperature. The properties of interest are specific heat capacity, thermal conductivity, thermal diffusivity and density. A designed deep fat frying experiment of sweetpotato was carried out under four different oil temperatures (150, 160, 170 and 180°C) and using three different sample sizes (defined as ratio of diameter to thickness (D/L: 2.5, 3.5 and 4.0). Convective heat transfer coefficients under these frying conditions were estimated and computer simulation based on finite element modeling technique was used to determine convective mass transfer coefficients. Correlation between heat transfer coefficient and mass transfer coefficient were investigated with reliable statistical tool. Effects of sample size, oil temperature and frying time on heat and mass transfer were also studied. <p>Specific heat, thermal conductivity and thermal diffusivity of sweetpotato were all found to increase with increase in temperature and moisture content. Density decreased with increase in moisture content. Maximum heat transfer coefficient reached during sweetpotato frying was in the range of 700-850 W/m2.°C. Heat transfer coefficient of sample during frying increased with increase in frying oil temperature but decreased with increase in sample size. Same trend for heat transfer coefficient was observed for effects of oil temperature and sample size on mass transfer coefficient. Maximum mass transfer coefficient reached during sweetpotato frying was in the range of 4×10-6 to 7.2×10-6 kg/m2.s. No general relationship was established between heat transfer coefficient and mass transfer coefficient during frying but a relationship was established between maximum heat transfer coefficient and maximum mass transfer coefficient. A trend was also observed between maximum heat transfer coefficient and the corresponding mass transfer coefficient at that point.
447

Heat and Mass transfer in an absorption process with mixed absorbent solution

Chi, Ten-yen 02 September 2011 (has links)
Falling film absorption process is studied for the simulation of the absorber of the absorption solar cooling system. In this study, we use different absorbents such as lithium chloride aqueous solution, and mixed solutions of lithium and calcium chloride aqueous solution, and water is the refrigerent. We also discuss the effects of various parameters of the absorbents such as the solution flow rate (the Reynolds number), the solution inlet temperature and the absorber vapor pressure. The results of the present study can provide the design reference for the absorption solar cooling systems.
448

The Implementation of Real-time Transmission with Partial Reliability in Wide Area Networks

Lin, Pin-hsin 12 September 2012 (has links)
Due to the rapid development of the Internet and the fast expansion of the bandwidth, the requirement of the real-time service for the Internet is necessary. In this way, the problem of the real-time service for the Internet becomes an important issue. Most of the applications still use TCP as the protocol, but due to the reliable property of TCP, TCP can¡¦t fit the requirement of the real-time transfer. So, we need to implement a protocol which we can use on the real-time transfer service. According to the requirement, we find an open source application layer protocol ¡V UDT (UDP-based Data Transfer). We can implement the application of real-time transfer by using the partial reliable messaging property of the protocol. In addition, user can adjust the parameters or settings of the protocol to make their application get into better performance by using the composable property of the protocol. In our research, we¡¦ll compare with RTP (Real-time Transport Protocol) and UDT, and also explain the reason why we don¡¦t choose RTP in our research. The assumption environment of our research is financial real-time service, and the protocol of such applications is TCP. In this way, we¡¦ll analyze and compare the result of the tests between TCP and UDT. We¡¦ll also adjust the parameters of the protocol to test the performance of the UDT under the environment of the real-time transfer, such as data lose rate, etc.. These results can supply the reference for the users when using UDT as their protocol to implement their real-time applications.
449

Simulation of vertical ship responses in high seas

Rajendran, Suresh 15 May 2009 (has links)
This research was done to study the effect of sea severity on the vertical ship responses like heave and pitch. Model testing of a 175m moored container ship with zero heading speed was done for different sea states varying from very rough to very high seas. Transfer functions were extracted using Volterra model which constitutes both linear and quadratic part. The experimental linear transfer functions were calculated using Volterra linear model and were compared with linear transfer function from the hydrodynamic theory. Experimental second order transfer functions were also extracted using Volterra quadratic model and their behavior was studied for different sea states. After the extraction of linear and second order transfer functions total responses were reconstructed and compared with the measured responses. This also helped to investigate the contribution of second order part to the total vertical ship responses. In the last stage of the research a new semi- empirical method was developed called as ‘UNIOM’ for the prediction of the responses. Laboratory input waves and theoretical LTFs were used for the simulation of ship response and these were compared with measured responses.
450

Multidirectional Wear and Transfer Film Formation in Polyetheretherketone

Laux, Kevin 2012 May 1900 (has links)
Polyetheretherketone (PEEK) is a designation given to materials of the polyaryletherketone family having a characteristic distribution of ether and ketone groups in the polymer backbone. PEEK materials have high strength and chemical resistance as well as very high melting points and glass transition temperatures. Because of this combination of properties, PEEK materials find use for wear application in extreme environments where they provide a light-weight and corrosion resistant bearing material that often does not require lubrication. An initial study focused on determining the effects of supplier and molecular weight on the wear of particular PEEK materials, in addition to the effect of contact pressure. This work is significant because it highlights the fact that tribologically relevant polymers, such as PEEK materials, vary greatly in terms of their polymer morphology and processing history, and this variation must be recognized by investigators when reporting wear data. Because of their light weight, chemical resistance, and self-lubricating properties, polymers are used in applications ranging from biomedical to aerospace. Some polymers exhibit significant differences in wear resistance based on whether they are in unidirectional or multidirectional sliding. Shear induced polymer chain orientation is believed to be responsible for this behavior. Polyetheretherketone (PEEK) has excellent wear resistance, but its multidirectional sliding behavior has not been thoroughly investigated. A factorial multidirectional pin-on-plate wear study of PEEK was conducted with a focus on molecular weight and sliding path directionality. These factors were studied for their correlation to overall wear performance. Additionally, transfer film thickness was measured at locations along the wear path using white light interferometry. A result of this work has been a greater understanding of PEEK wear mechanisms in various sliding configurations and how they relate to transfer film formation. A major outcome was the development of a quantitative metric to describe transfer film thickness and continuity. It was found that thinner more continuous transfer films form under sliding conditions that change direction rather than overlapping along the same path. The thinner more continuous transfer film was found to also correspond with statistically lower wear behavior. Scanning electron microscope (SEM) investigation of the transfer film and pin wear surface confirmed the relationship between transfer film quality and wear.

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