Dissertations / Theses: 'Modes of Transfer'

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LeMaster, Jane. "The Relationship Between Environmental Barriers and Modes of Technology Transfer: A Study of United States Companies with Operations in Mexico." Thesis, University of North Texas, 1994. http://catalog.hathitrust.org/api/volumes/oclc/33036035.html.

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Azari, Jian. "Transmission of mixed video, speech and data services over ATM networks." Thesis, University of Essex, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.333498.

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Abbott, Stephen Barnes. "Energy transfer between surface plasmon polariton modes with hybrid photorefractive liquid crystal cells." Thesis, University of Southampton, 2012. https://eprints.soton.ac.uk/210379/.

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In this thesis, a hybrid photorefractive liquid crystal cell structure with the addition of a thin 40nm Gold layer is proposed that demonstrates significant photorefractive control of Surface Plasmon Polaritons (SPP). The photorefractive effects are generated through optically controlling the conductivity of a ~100nm photoconducting poly-N-vinyl-carboxyl (PVK) layer. Therefore, when a potential is applied across the cell, the liquid crystal alignment and the SPP wavevector is able to be controlled with light. The aim for developing this device is for the eventual demonstration of SPP gain to offset the high optical losses and increase the characteristically short propagation length of SPP. The mechanism we intend to use to demonstrate gain is analogous to the asymmetric energy transfer in a wave mixing system for two laser beams used to typically characterise photorefractive materials. We first characterise the electrical and optical behaviour of the novel photorefractive plasmonic structure proposed with uniform illumination. Our system demonstrates a good photorefractive wavevector shift of 0.207μm-1 for a 1.24eV SPP; this shift is in excess of the FWHM of the SPP resonance in the attenuated total reflection spectrum (0.154μm-1). However, the electric behaviour of the system is found to be highly complex and cannot be fully characterised by an equivalent electrical circuit. In addition, due to electronic stability issues, we require a slow AC potential to demonstrate consistent photorefractive effects. In a step towards realising SPP gain, we then consider the SPP interaction with a refractive index grating written into the liquid crystal layer with the interference pattern of crossed laser beams. We find that a SPP is diffracted into additional SPP modes. Our investigation then determines the ideal parameters that maximise the energy transfer by examining the diffraction efficiency dependence of each variable of the system. The maximum energy transfer observed is 25.3±2.3% for a 1.05eV SPP from a 4μm grating. With the assistance of a numerical simulation of our system we present a series of qualitative and semi-analytical descriptions to describe the mechanisms behind the observed trends. We discover that the diffraction efficiency is dependent of three important effects; the orientation of the grating, the penetration depth of the SPP into the liquid crystal and the magnitude of the periodic electric field in the liquid crystal. In addition, to fully describe the quantitative values observed we must also consider the presence of a thin 100nm region of the liquid crystal near the photoconductor interface that does not strongly respond to the applied electric field due to anchoring forces

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Jana, Subha. "Biodetection using fluorescence energy transfer from Quantum dot excited whispering gallery modes to fluorescent acceptors." Electronic Thesis or Diss., Université Paris sciences et lettres, 2021. http://www.theses.fr/2021UPSLS081.

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La quantification de biomarqueurs spécifiques est un outil de diagnostic important. Les tests immunologiques standards tels que ELISA nécessitent de nombreuses étapes de lavage et une amplification du signal, en particulier à faible concentration. D'autre part, le transfert d'énergie résonant de type Förster (FRET) a été utilisé pour concevoir des tests biologiques homogènes en une seule étape qui ne nécessitent aucune étape de lavage, où le biomarqueur permet la formation d'un complexe "sandwich" impliquant des anticorps marqués par le donneur et d'autres marqués par l'accepteur. Le FRET du donneur vers l'accepteur fournit alors une signature optique de la formation du complexe, et donc du biomarqueur d'intérêt. Cependant, le FRET, qui est très sensible à la distance donneur-accepteur, ne se produit à un taux significatif que lorsque la distance donneur-accepteur est inférieure à 10 nm; la grande taille de nombreux complexes biologiques limite l'efficacité du transfert d'énergie, empêchant une détection sensible. Je propose ici une nouvelle modalité de transfert d'énergie qui utilise des microcavités optiques en solution. Ensuite, je décris un schéma de biodétection pour détecter un oligonucléotide biomarqueur de cancer en solution.À cette fin, j'ai conçu des structures de microcavité dans lesquelles des nanocristaux fluorescents sont placées à l'intérieur de microsphères diélectriques pour permettre un couplage fort de leur émission de fluorescence avec les modes de résonance de la cavité, appelés modes de galerie (WGM). J'ai étudié les propriétés structurelles et optiques de ces microcavités optiques. J'ai également caractérisé le transfert d'énergie entre ces modes et des nanoparticules acceptrices chargées de colorants présentes dans le champ évanescent, à quelques dizaines de nm au-dessus de la surface des microsphères. J’ai développé un modèle analytique pour caractériser les mécanismes de transfert d'énergie médié par les WGM (WGET). De plus, une comparaison entre WGET et FRET a révélé la supériorité du WGET dans le contexte de la construction de capteurs en termes de sensibilité et de portée de détection. Dans la dernière partie de la thèse, j’ai développé une stratégie pour fonctionnaliser ces microcavités optiques et leur permettre d'interagir avec des analytes cibles tels que l'ADN, l'ARN et les protéines avec une bonne spécificité. Cette stratégie a ensuite été adaptée pour fixer des sondes de capture d'ADN sur les microcavités activées par WGM. En utilisant les microsphères fixées à l'ADN comme donneur optique en combinaison avec des nanoparticules de colorants fonctionnalisées par un ADN complémentaire comme accepteurs optiques, un test de biodétection a été démontré avec succès pour détecter en solution un biomarqueur de cancer appelé survivine. Ce test a démontré une bonne sensibilité envers la cible, et s'est également avéré très spécifique. Le schéma de détection a été démontré dans un microscope confocal, au niveau de microsphères individuelles, puis transposé avec succès dans un instrument beaucoup plus simple tel qu'un spectrofluoromètre qui mesure la fluorescence de l'ensemble de la solution; la signature de la formation d'un complexe sandwich a été détectée efficacement.En conclusion, j'ai démontré que le transfert d'énergie assisté par microcavité présente plusieurs avantages par rapport aux tests FRET ordinaires. Un véritable test de biodétection basé sur le principe du WGET a également été conçu avec succès pour détecter des biomarqueurs du cancer avec une sensibilité et une spécificité élevées. Cette étude ouvre donc de nombreuses possibilités pour concevoir des tests plus performants et plus précis pour détecter diverses entités biologiques Quantification of specific biomarkers is an important diagnostic tool. Standard immunoassays such as ELISA require extensive washing steps and signal amplification, in particular when the biomarker of interest is only present at very low concentrations. On the other hand, non-radiative Förster resonance energy transfer (FRET) has been used to design one-step homogenous bioassays which do not require any washing steps, where the biomarker enables the formation of a sandwich complex involving donor-labeled and acceptor-labeled antibodies. FRET from the donor to the acceptor then provides an optical signature of the complex formation, hence of the biomarker of interest. However, FRET which is highly sensitive to the donor-acceptor distance, only occurs in a significant rate when the distance between the donor and acceptor is less than 10 nanometers; thus the large size of many biological complexes limits the efficiency of energy transfer, preventing sensitive detection. Here I propose a novel energy transfer modality that uses solution-phase optical microcavities to enhance energy transfer. Following that, I describe a bio-sensing scheme designed to detect a cancer biomarker DNA in solution.To this aim, I have designed microcavity structures in which fluorescent colloidal quantum dots are located inside dielectric polymer microspheres to enable strong coupling of their fluorescence emission with the cavity resonance modes or whispering gallery modes (WGMs) of the microspheres. A detailed study was carried out to comprehend the structural and optical properties of these optical microcavities. I also characterized the energy transfer between these modes and acceptor dye-loaded nanoparticles present in the evanescent field, within a few tens of nanometers above the microsphere surface. An analytical model was constructed to provide insights into the WGM mediated energy transfer (WGET) mechanisms. Moreover, a comparison between WGET and FRET revealed the superiority of WGET in the context of building sensors with improved sensitivity and longer range of detection. In the last part of the thesis, a strategy is discussed in detail to provide biological functionalities to these optical microcavities which would enable them to interact with target analytes such as DNA, RNA, and proteins with high specificity, and moreover to reduce non-specific interactions. This strategy then was adapted to attach DNA capture probes onto the WGM enabled microcavities. Using the DNA attached microspheres as optical donor in combination with probe-DNA functionalized dye nanoparticles as optical acceptors, a biosensing assay has been successfully demonstrated to detect a cancer biomarker DNA called survivin in the solution phase. This assay did not only show good sensitivity towards the target, but also it has proven to be highly specific. The detection scheme has been demonstrated in a sophisticated confocal microscope at the single microsphere level, then successfully translated to a much simpler spectrofluorometer that measures fluorescence from the whole sample solution; the signature of the sandwich complex formation was also effectively detected.In conclusion, I demonstrated that microcavity-assisted energy transfer has several advantages over regular FRET assays. A real bio-sensing assay based on the WGET principle has also been successfully designed to detect cancer biomarkers with high sensitivity and specificity. This study thus opens up many possibilities to design high-performing and more accurate assays to detect varieties of biological entities

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Early, Jeffrey Bryan. "Research Centers as Modes of Technology Transfer between the University and Industry and the Implications for Public K-12 Schools." Diss., Virginia Tech, 2007. http://hdl.handle.net/10919/26390.

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The Institute for Advanced Learning and Research (IALR) is located in the south central region of Virginia commonly known as "Southside". The IALR was established in 2002 by the Code of Virginia for the primary purpose of revitalizing this economically distressed area of Virginia. The education of the citizenry of this area is central to this purpose. One method of providing for this purpose is partnering with the school divisions within the service region of the IALR to provide increased access to educational opportunities. The service region of the IALR includes eight school divisions. The purpose of this study was to determine the perceived needs of K-12 educators in the service region of the IALR in Southside Virginia. Teachers, principals, superintendents, and directors of instruction from each school division in the study area received a hyperlink to a separate survey instrument in which items were selected for inclusion that likely match the participant's knowledge based upon his or her job title. Specifically, they provided their perceptions on teaching staff development needs, administrative staff development needs, curricular needs, and the other needs they may have. Descriptive statistics were used to report the data designed to identify the needs of the eight school divisions in this geographic area. The census survey method was used to collect data from the eight school divisions served by the IALR returned data from 100% of the superintendents and directors of instruction, 70.4% of principals, and 6.4% of teachers within these school divisions. The low response rate for teachers made the value of their perceptions problematic. The findings of the study indicate an overall perceived need for staff development in the areas of special education, science, math, reading, At-Risk programs, and technology. Further, all respondents indicated a desire for greater access to graduate programs, and a majority of participants expressed a desire to have greater communication with the research center in their area. Ph. D.

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Simmons, Justin French. "Complete and Exact Small Signal Analysis of DC-to-DC Switched Power Converters Under Various Operating Modes and Control Methods." PDXScholar, 2011. https://pdxscholar.library.pdx.edu/open_access_etds/195.

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A method to obtain the exact control-to-output and input-to-output transfer functions for switched DC-to-DC pulse-width modulated power converters is applied to different combinations of operating conditions such as continuous conduction mode (CCM), discontinuous conduction mode (DCM), and discontinuous voltage mode (DVM) and methods of control such as normal voltage mode (NVM), current programming mode (CPM), and V-squared control. The majority of these combinations have not previously had their transfer functions of interest derived to the accuracy provided by the method. The derivation of the method is covered, and the results from its application are verified by simulation. The simulation method is also justied and proposed as an improvement to the methods used by simulation engines for switched mode power supply design such as SIMPLIS.

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Larsson, Filip, and Anna Thorsell. "Knowledge Transfer and The Timing of Information Technology Methods : A study within six organizations in Sweden during the COVID-19 pandemic." Thesis, Högskolan i Gävle, Företagsekonomi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-36218.

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Abstract Title: Information Technology and the Timing of Knowledge Transfer Methods: A study within six organizations in Sweden Level: Master Thesis for Master’s Degree in Business Administration Author: Anna Thorsell and Filip LarssonSupervisor: Daniella FjellströmExaminer: Ehsanul Huda Chowdhury Date: 2021 June Aim: It has been stated that knowledge transfer processes fail due to poorly timed transfer methods and that it is of importance to understand underlying mechanisms of transfer. It has also been argued that information technology (IT) systems can increase knowledge transfer in organizations. This study aims to research the influence IT has on the timing of transfer methods and knowledge transfer. The authors of this study discovered a gap for the use and timing of IT transfer methods and its influence on knowledge transfer within organizations in existing research. Method: This study included the use of secondary data from a literature review, as well as primary data using a qualitative research method with an inductive approach as semi- structured in-depth interviews were conducted for a multi-case study. The interviews were held with individuals working in six organizations in Sweden. Phases of analysis including content analysis and data coding were used for the analysis and reporting of the data collected. Findings and Conclusion: The study showed that IT provides platforms for knowledge transfer through different types of IT and IT transfer methods used. That the type of IT chosen can depend on the urgency of the transfer, what type of knowledge is transferred as well as the amount of knowledge transferred. That the timing of IT transfer methods I can speed up knowledge transfer as it enables the transfer to happen faster and in later stages of the transfer process due to providing direct knowledge transfer channels and accessible knowledge to all members of a team. It was shown that IT transfer methods can influence internal stickiness, decrease causal ambiguity and reduce the knowledge barrier of arduous relationships as well as influence the use of front-loading and back- loading modes of transfer. That the urgency of transfer can be a determining factor for the modes used rather than the level of causal ambiguity of the knowledge. Contribution of the Study: This study contributes to studies on types of IT and IT transfer methods used in organizations for knowledge transfer. It adds to existing research on timing of knowledge transfer methods including both explicit and tacit knowledge, as well as adding the influence of IT on the timing of knowledge transfer methods, knowledge transfer, internal stickiness, knowledge barriers and affordance of interaction. It provides new findings to the timing of knowledge transfer from the timing of types of IT and IT transfer methods used based on the urgency of transfer and what type of knowledge that is being transferred. The study contributes to highlighting the value of IT for the management of knowledge transfer within organizations, especially due to global events such as the COVID-19 pandemic. The study provides a basis for managers to examine their use of IT for knowledge transfer in organizations. It also showcases the continuous increased need for effective knowledge transfer processes between organizations, people and across locations and how IT can facilitate that. Study Reflections and Suggestions for Future Research: This study included individuals from six organizations. It is suggested to include more participants for future studies as well as investigating teams, departments and organizations on narrow as well as on broader levels in different sectors to gain deeper insight into the field. Further research on how the urgency of transfer affects the modes of transfer used is also advised. Keywords: Knowledge, Knowledge Transfer, Methods of Transfer, Timing, Modes of Transfer, Internal Stickiness, Information Technology, COVID-19

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Gomez, Giraldo Evelio Andres. "Observations of energy transfer mechanisms associated with internal waves." University of Western Australia. Centre for Water Research, 2007. http://theses.library.uwa.edu.au/adt-WU2007.0045.

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[Truncated abstract] Internal waves redistribute energy and momentum in stratified lakes and constitute the path through which the energy that is introduced at the lake scale is cascaded down to the turbulent scales where mixing and dissipation take place. This research, based on intensive field data complemented with numerical simulations, covers several aspects of the energy flux path ranging from basin-scale waves with periods of several hours to high frequency waves with periods of few minutes. It was found that, at the basin-scale level, the horizontal shape of the lake at the level of the metalimnion controls the period and modal structure of the basin-scale natural modes, conforming to the dispersion relationship of internal waves in circular basins. The sloping bottom, in turn, produces local intensification of the wave motion due to focusing of internal wave rays over near-critical slopes, providing hot spots for the degeneration of the basin-scale waves due to shear instabilities, nonlinear processes and dissipation. Different types of high-frequency phenomena were observed in a stratified lake under different forcing conditions. The identification of the generation mechanisms revealed how these waves extract energy from the mean flow and the basin-scale waves. The changes to the stratification show that such waves contribute to mixing in different ways . . . Detailed field observations were used to develop a comprehensive description of an undocumented energy flux mechanism in which shear-instabilities with significant amplitudes away from the generation level are produced in the surface layer due to the shear generated by the wind. The vertical structure of these instabilities is such that the growing wave-related fluctuations strain the density field in the metalimnion triggering secondary instabilities. These instabilities also transport energy vertically to the thermocline where they transfer energy back to the mean flow through interaction with the background shear.

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Winnard, Thomas Johan. "Theoretical Parametric Study of Through-Wall Acoustic Energy Transfer Systems." Thesis, Virginia Tech, 2021. http://hdl.handle.net/10919/103387.

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Technological advances require novel solutions for contactless energy transfer. Many engineering applications require unique approaches to power electrical components without using physical wires. In the past decade, awareness of the need to wirelessly power electrical components spawned many forays into the field of wireless power transfer (WPT). WPT techniques include capacitive energy transfer, electromagnetic inductive power transfer, electromagnetic radiative power transfer, electrostatic induction, and acoustic energy transfer. Acoustic energy transfer (AET) has many advantages over other methods. These advantages include lower operating frequency, shorter wavelengths enabling the use of smaller sized receiver and transmitter, extended transmitter-to-receiver distance therefore more manageable design constraints, achieving lower attenuation, higher penetration depth, and no electromagnetic losses. Most AET systems operate in the ultrasonic frequency range and are more commonly referred to as ultrasonic acoustic energy transfer (UAET) systems. Through-wall UAET systems are constructed of a transmitter bonded to a transmission elastic layer, which in turn is bonded to a receiver. The transmitter and receiver layers are constructed of a piezoelectric material. Piezoelectric materials behave according to the piezoelectric effect, which is when a material generates an electric charge in response to mechanical strain. The transmitter utilizes the reverse of the piezoelectric effect. A sinusoidal input voltage is applied to the transmitter, inducing vibrations in the transmitter. The vibration-induced acoustic waves emanating from the transmitter travel through the initial bonding layer, the transmission layer, and the final bonding layer to the receiver. In turn, the acoustic waves cause the receiver to deform and undergo strain. This induces a flow of charge in the receiver, which is an electric current. The receiver feeds current to a resistive load. In this manner, energy is acoustically transferred between two transducers without wires. The performance of UAET systems can be evaluated based on power transfer efficiency, voltage magnification, and input admittance. UAET systems require extensive modeling before experimental assembly can be attempted. The analytical models of UAET are either based on the mechanics of the constitutive relations of piezoelectricity and solid mechanics or using equivalent circuit methods. The equivalent circuit method approximates the physics of the UAET system with electrical assumptions. The mechanics-based method is the most comprehensive description of the physics of all the intermediate layers in a UAET system. The mechanics-based method has been based on the assumption that the UAET system is operated in the thickness mode of vibration, i.e., piston-like vibration mode where the transmitter and receiver disks vibrate only in the thickness direction. This poses an issue for disks with aspect ratios between 0.1 and 20 because the piezoelectric transducers vibrate in both the radial and thickness modes. In addition to this assumption, most of the works on UAET models only have accounted for the piezoelectric and transmission layers. The effects of the bonding layers were not considered. Bonding the piezoelectric layers to the transmission layer introduces epoxy material with mechanical properties that are not accounted for. The epoxy layers are extra barriers to the transmission that introduce attenuation and alter the vibrational and acoustical behaviors of the UAET system. Investigations into UAET commonly focus on metal through-wall applications. Alternate transmission layer materials are not investigated and the impact of varying mechanical properties on the performance of a through-wall UAET system has not been comprehensively studied. Even with the metal transmission layers, the impact of the metal thickness has not been extensively investigated thoroughly. This work addresses the issues of the thickness-mode assumption in UAET modeling, the effects of epoxy layers, the impacts of the metal layer geometry, and the performance of UAET systems with alternate transmission layer materials. Particularly, (1) we showed that the thickness-mode assumption, that has been used in the UAET modeling leads to inaccurate results. (2) We modified the available acoustic electro- elastic theoretical modeling to include the effects of radial modes as well as the epoxy bonding layers. (3) We showed that the geometry of the elastic/metal layer requires optimization for peak system efficiency. (4) The results show that using alternate transmission layer materials impacts the performance of UAET systems. The results of this work were investigated using an improved 5-layer analytical model and finite element modeling in COMSOL Multiphysics. Master of Science Wireless power transfer (WPT) is an innovative solution to the problem of powering sophisticated technological applications. Such instances include the powering of implanted medical devices, recharging inaccessible sensor networks, and wireless powering of components in sealed containers. Acoustic energy transfer (AET) is a feasible WPT method that addresses these needs. AET is based on the propagation of acoustic waves to a piezoelectric receiver which converts the vibrations caused by incident acoustic waves into electrical energy. Most AET systems operate in the ultrasonic frequency range, and so AET can also be referred to as ultrasonic acoustic energy transfer (UAET). Through-wall UAET systems are constructed from a transmitter that is bonded to a transmission elastic layer. The transmission layer is bonded to a receiver. The transmitter and receiver are made of a piezoelectric material. This thesis addresses the modeling process of through-wall UAET systems. In previous works, the fundamental assumption has been that such systems vibrate purely in the thickness mode. Additionally, other investigations did not comprehensively analyze the effects of the bonding layers, ascertain the performance of non-metal transmission layers, or provide practical insight on the effect of the resistive loading on such systems. This work addresses all these issues with a mathematical framework and finite element modeling results.

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Sbaibi, Ahmed. "Contribution à l'étude du comportement statique et dynamique des capteurs thermiques (fils froids, fils chauds et thermocouples) en présence de différents modes de transferts thermiques." Rouen, 1987. http://www.theses.fr/1987ROUES030.

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Etude à la fois théorique et expérimentale dans le cas des écoulements gazeux subsoniques. Les résultats expérimentaux relatifs aux constantes de temps des capteurs dans des situations convectives ou radiatives et aux fonctions de transfert des fils chauds et fils froids sont en bon accord avec l'analyse théorique présentée dans ce mémoire

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Hemais, Carlos Alberto. "Firm-level transfer of technology : an empirical study of modes of international commercialisation of technology in British industry." Thesis, University of Warwick, 1992. http://wrap.warwick.ac.uk/3840/.

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The thesis examines the process of technology transfer in British firms. The literature on modes, causes and effects of technology transfer says little about how British firms transfer their technology abroad. A firm-level study was chosen because most international technology transfer happens not between countries but between firms, even if these firms are in different countries. The present research uses data from British industry, which is still one of the major sources of technology in the world and its firms represent an important example of the role of technology supplier. The adopted methodology consisted of a pilot study, conducted through interviews with executives related to technology in six different firms, using a semi-structured questionnaire, and a survey, conducted through a structured mail-questionnaire, sent to British firms which transfer technology overseas. In the light of an extensive literature review and the pilot study, several non-exclusive dimensions of the transfer of technology related to home market, . technology, foreign government policy, firm's attribute and foreign market were identified and an analytical framework was developed, aggregating those dimensions, that were tested through the survey. The findings suggest that two main groups emerged from the sample. One is described as market/investment led. Its firms usually transfer their latest technology, prefer licensing as their main form of going abroad, are more aggressive, impulsive and dynamic and they transfer their technologies independent of their concerns about the consequences that it can bring to them. The other group is described as control/relationship orientated and its firms are more conservative, follow an incremental mode of internationalisation, do not transfer their latest technology and tend to collude with other firms in a foreign market. The decision of the firms on international operations is generally not influenced by characteristics of the home market or the age of technology. Similarly, attributes of the firms do not appear to have a major influence. Foreign government policy is recognised as very important in defining the process of technology transfer and attributes of foreign markets are important enough to motivate firms to go abroad.

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Kotschy, P. J. "Modelling directional casting processes in which heat conduction and cavity radiation are the dominant modes of heat transfer." Doctoral thesis, University of Cape Town, 2002. http://hdl.handle.net/11427/5522.

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Includes bibliographical references. Directional investment casting processes involve complex interactions of various mechanisms of heat and mass thansfer in spatially complex domains and in the presence of a change of phase. In particular, the transfer of heat within the furnace occurs in the form of conduction, convection and radiation. This thesis addresses the development of computational techniques to simulate, at a macroscopic scale, such casting processes. In this study the conservation of heat energy within the casting is assumed to be maintained by conduction, accompanied by the release of latent heat energy during solidification. The overall state of the radiation in the furnace chamber is analysed in terms of the absorbed, emitted and reflected energies for each surface defining the geometry of the chamber. By applying a diffuse-grey approximation to these energies, an expression for the net flux for each surface is derived.

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Pretorius, Morné. "Comprehensive active magnetic bearing modelling taking rotor dynamics into account / M. Pretorius." Thesis, North-West University, 2008. http://hdl.handle.net/10394/2647.

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The McTronX Research Group at the North-West University is conducting research in the field of Active Magnetic Bearings (AMBs) with the aim of establishing a knowledge base for future industry consultation. AMBs are environmentally friendly and are a necessity in the pebble bed modular reactor (PBMR), a South-African initiated project, which is predicted to be the means of supplying Africa and many other countries with modular energy in the future. Aside from the PBMR, there are numerous other AMB industrial applications. The aim of this project is to develop a comprehensive AMB model that considers the effect that rotor dynamics has on an AMB system. This model is used to analyse a double radial AMB, capable of suspending a rigid- and flexible rotor, to explain previously noticed phenomena. Two modelling methods are focussed on namely the System Matrix Method and Transfer Matrix Method (TMM) both of which are implemented in MATLAB®. The rigid rotor model is firstly implemented as a point mass in state-space form followed by use of the TMM to analyse its bending modes. The stability and critical speeds of the system are analysed due to a change in the supports' properties along with rotor gyroscopy and its effect on the system. During analysis of the flexible rotor the TMM was used via a similar approach as was followed with the rigid rotor. The results indicate that the system is experiencing lower than expected damping due to the model that is used within the control loop. The previously assumed rotor model in the control loop is not sufficient to describe its complex behaviour. This causes the unexpected damping characteristics. This project suggests future work to be conducted in expanding the frequency domain model of the rotor within the control loop to account for its physical shape. Thesis (M.Ing. (Computer and Electronical Engineering))--North-West University, Potchefstroom Campus, 2009.

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Do, Pete Binh. "Effect of textile preform structure on the mechanical properties and failure modes of composites from resin transfer molding process." Thesis, Georgia Institute of Technology, 1994. http://hdl.handle.net/1853/8512.

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Schoth, Mario [Verfasser], Andreas [Akademischer Betreuer] Knorr, and Thomas [Akademischer Betreuer] Renger. "Theory of excitation transfer in nanostructures influenced by vibrational modes / Mario Schoth. Gutachter: Andreas Knorr ; Thomas Renger. Betreuer: Andreas Knorr." Berlin : Technische Universität Berlin, 2014. http://d-nb.info/1067387749/34.

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Wachsmann-Hogiu, Sebastian. "Vibronic coupling and ultrafast electron transfer studied by picosecond time resolved resonance Raman and CARS spectroscopy." Doctoral thesis, [S.l. : s.n.], 2000. http://deposit.ddb.de/cgi-bin/dokserv?idn=960830898.

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Romano, Maria Cecilia [UNESP]. "Funções de Wannier para cristais fotônicos unidimensionais." Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/99679.

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Made available in DSpace on 2014-06-11T19:30:18Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-04-18Bitstream added on 2014-06-13T20:20:42Z : No. of bitstreams: 1 romano_mc_me_bauru.pdf: 1627459 bytes, checksum: 18d280916e43c7dadfd84a8bfbb6e9f0 (MD5) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Os cristais fotônicos são novos materiais em que a permissividade dielétrica e a permeabilidade magnética apresentam a periodicidade de uma rede de Bravais. No caso dos sólidos cristalinos, é a energia potencial de cada elétron que apresenta esse tipo de periodicidade. Por conta das semelhanças que existem entre as equações que descrevem os sintomas eletrônicos e fotônicos, muitos dos conceitos e métodos da teoria de estados eletrônicos vêm sendo aplicados na investigação de cristais fotônicos. Dentre esses conceitos, as funções de Wannier apresentam vantagens para o tratamento de estados eletrônicos e modos fotônicos localizados. Este trabalho aborda o caso de cristais fotônicos unidimensionais com simetria de inversão. Primeiramente são calculados e analisadas funções de Wannier bem localizadas. Em seguida são investigados os modos eletromagnéticos localizados produzidos por defeitos em cristais fotônicos, utilizando o método de matriz de transferência e o método da combinação linear das funções de Wannier. Finalmente, é feita a comparação dos resultados obtidos mediante esses métodos e são discutidas as vantagens do uso de funções de Wannier Photonic crystal are new materials where both the dielectric permittivity and the magnetic permeability present the periodicity of a Bravais lattice. In the case of electronic states, this property is shown by the mono-eletronic potential energy. Due to the similarities between the eletronic and photonic problems, many concepts and methods of theory of electronic states are being applied to investigate photonic crystals. Among such concepts, the Wannier functions are advantageous to deal with either localized photonic modes. This work addresses the case of one-dimensional photonic crystals with inversion symmetry. First, well-localized Wannier functions are calculated and analyzed. Then, the localized modes produced by defects in photonic crystals are investigated by using either transfer matrices or linear combination Wannier functions. Finally, the results obtained by the two methods are compared and the advantages of using Wannier functions are discussed

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Soderquist, Daniel Robert. "Analysis of Distortion Transfer and Generation through a Fan and a Compressor Using Full-annulus Unsteady RANS and Harmonic Balance Approaches." BYU ScholarsArchive, 2019. https://scholarsarchive.byu.edu/etd/7401.

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Understanding distortion transfer and generation through fan and compressor blade rows is able to assist in blade design and performance prediction. Using full annulus unsteady RANS simulations, the effects of distortion as it passes through the rotor of a transonic fan at five radial locations (10%, 30%, 50%, 70%, and 90% span) are analyzed. The inlet distortion profile is a 90-degree sector with a 15% total pressure deficit. Fourier distortion descriptors are used in this study to quantitatively describe distortion transfer and generation. Results are presented and compared for three operating points (near-stall, design, and choke). These results are used to explain the relationship between inlet total pressure distortion, pressure-induced swirl, total pressure distortion transfer, total temperature distortion generation, and circumferential rotor work variation. It is shown that very large changes in pressure-induced swirl and distortion transfer and generation occur between near-stall and design, but only small changes are seen between design and choke. The greatest changes are shown to be near the tip. Local power variations are shown to correlate with total pressure distortion transfer and total temperature distortion generation.It can be difficult to predict the transfer of distortion through a fan or compressor because traditional experimental and computational methods are very expensive and time consuming. The Harmonic Balance approach is a promising alternative which uses Fourier techniques to represent fluid flow solutions and which can provide unsteady solutions much more quickly than traditional unsteady solvers. Relatively little work has been done to assess how much Fourier information is necessary to calculate a sufficiently accurate solution with the Harmonic Balance Solver. A study is performed to analyze the effects of varying the amount of modal content that is used in Harmonic Balance simulations. Inlet distortion profiles with varying magnitudes are used in order to analyze trends and provide insight into the distortion flow physics for various inlet conditions. The geometry is a single stage axial compressor that consists of an inlet guide vane followed by the NASA Stage 37 rotor. It is shown that simulations with greater magnitudes of distortion require more modal content in order to achieve sufficiently accurate results. Harmonic Balance simulations are shown to have significantly lower computational costs than simulations with a conventional unsteady solver.

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Thaunay, Florian. "Développement de champs de forces polarisables et applications à la spectroscopie vibrationnelle." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLX037/document.

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La spectroscopie de dissociation par absorption de photons infrarouges (IRPD) permet d’obtenir les signatures vibrationnelles d’espèces chargées en phase gazeuse, telles que de petits peptides ou des ions hydratés dans des agrégats d’eau. L’attribution des modes de vibration pour établir une relation entre le spectre expérimental et une structure moléculaire est une tâche délicate et nécessite le recours à la modélisation moléculaire.Ce manuscrit présente un ensemble d’outils théoriques pour le calcul et l’attribution de spectres vibrationnels, basée principalement sur la dynamique moléculaire classique et le champ de forces polarisable AMOEBA, ainsi que son application à des ions gazeux de tailles diverses. Les ions hydratés dans des agrégats d’eau M(H2O)n (n allant de 6 à 100) sont caractérisés par une dynamique importante, et leur spectre expérimental ne peut pas être décrit par une seule structure. La signature des peptides évolue avec la température et les effets d’anharmonicité dynamique. Ils peuvent également être le siège de mécanismes de transfert de proton, présentant une signature vibrationnelle très caractéristique.La surface d’énergie potentielle de ces systèmes est explorée par la dynamique moléculaire classique en trajectoires individuelles ou avec échange de répliques, afin d’engendrer des structures énergétiquement stables. Pour les plus petits systèmes, les méthodes quantiques DFT et post-HF sont utilisées pour confirmer les structures de plus basse énergie, calculer leurs spectres IR statiques et proposer des attributions des modes de vibration. Pour les plus systèmes de plus grandes tailles, c’est-à-dire les ions dans des gouttes d’eau de plusieurs dizaines de molécules, la simulation des spectres IR à température finie est basée sur la transformée de Fourier de la fonction d’autocorrélation du moment dipolaire (DACF), calculée pour une trajectoire de dynamique moléculaire classique. Cette méthode n’offrant pas d’accès direct aux modes normaux de vibration, nous avons implémenté une méthode d’attribution dynamique, basée sur la Driven Molecular Dynamics (DMD) et couplée au DACF. La combinaison AMOEBA/DACF/DMD a été utilisée pour reproduire et attribuer le spectre du dipeptide Ace-Phe-Ala-NH2, et ceux d’ions hydratés dans des agrégats d’eau.Enfin, la signature vibrationnelle d’un transfert de proton ne peut être décrite, ni par des méthodes statiques quantiques, ni par la dynamique classique. Sa modélisation a nécessité le développement d’un modèle Empirical Valence Bond (EVB) à deux états, couplé au champ de forces polarisable AMOEBA. Le modèle EVB a été implémenté dans la suite logicielle Tinker. Il permet de reproduire le comportement dynamique du transfert de proton au sein de petits peptides et de diacides déprotonés, ainsi que la signature spectroscopique observée expérimentalement.Une partie importante des applications de ces développements concerne des ions simples hydratés dans des nano-gouttelettes, et en particulier l’ion sulfate de grande importance environnementale. Nous avons pu reproduire de façon satisfaisante, pour la première fois, les spectres d’agrégats contenant jusqu’à 100 molécules d’eau. Le principal contributeur à cette spectroscopie expérimentale est l’équipe d’E. Williams à l’université de Californie à Berkeley. Nous avons établi avec eux une collaboration pour compléter ce travail en modélisant les spectres IR d’ions sulfates hydratés [SO4(H2O)n=9-36]2-, dont ils ont obtenu les signatures expérimentales Spectroscopy dissociation by absorption of infrared photons (IRPD) provides vibrational signatures of charged species in the gas phase, such as small peptides or hydrated ions in water clusters. The vibrational normal modes assignment to establish a relationship between the experimental spectrum and molecular structure is a delicate task and requires the use of molecular modeling.This manuscript presents a set of theoretical tools for calculation and assignment of vibrational spectra, based mainly on classical molecular dynamics and polarizable AMOEBA force field, and its application to gaseous ions of various sizes. Hydrated ions in water clusters M(H2O)n (n in 6-100 range) are characterized by a dynamic behavior, and their experimental spectrum can not be described by a single structure. The signature of peptides changes with temperature and dynamic anharmonicity effects. They can also be the site of proton transfer mechanisms, with a very characteristic vibrational signature.The potential energy surface of these systems is explored by classical molecular dynamics in individual trajectories or replica exchange to generate energetically stable structures. For smaller systems, quantum methods, as DFT and post-HF, are used to confirm the lowest energy structures, calculate their static IR and propose normal modes assignments. For larger systems, i.e ions in water drops of several tens of molecules, the simulation of IR spectra at finite temperature is based on the Fourier transform of the autocorrelation function of the dipole moment (DACF), calculated during a classical molecular dynamics trajectory. As this method does not allow direct access to the vibrational normal modes, we implemented a method of dynamic assigments, based on the Driven Molecular Dynamics (DMD) and coupled to the DACF. The combination AMOEBA /DACF / DMD was used to reproduce and assign the spectrum of the dipeptide Ace-Phe-Ala-NH2, and those of hydrated ions in water clusters.Finally, the vibrational signature of a proton transfer can not be described by quantum static methods or by classical dynamics. Its modeling required the development of a two states Empirical Valence Bond Model (EVB), coupled with AMOEBA polarizable force field. The two states EVB model was implemented in the software TINKER. It can reproduce the dynamic behavior of proton transfer in small peptides and deprotonated acids, as well as the spectroscopic signatures observed experimentally.An important part of the applications of these developments relates simple hydrated ions in nano-droplets, and in particular the sulfate ion of great environmental importance. We were able to reproduce satisfactorily, for the first time, the spectra of clusters containing up to 100 water molecules. The main contributor to this experimental spectroscopy is the team of E. Williams from the University of California of Berkeley. We have established cooperation with them to complete this work by modeling the IR spectra of hydrated sulfates ions [SO4(H2O) n=9-36]2-, for which they obtained experimental signatures

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Ruan, Kangping. "NUMERICAL AND EXPERIMENTAL TECHNIQUES FOR ASSESSING THE ACOUSTIC PERFORMANCE OF DUCT SYSTEMS ABOVE THE PLANE WAVE CUTOFF FREQUENCY." UKnowledge, 2018. https://uknowledge.uky.edu/me_etds/120.

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This research deals with determining the acoustic attenuation of heating, ventilation, and air conditioning (HVAC) ductwork. A finite element approach was developed for calculating insertion loss and breakout transmission loss. Procedures for simulating the source and receiving rooms were developed and the effect of structureborne flanking was included. Simulation results have been compared with measurements from the literature and the agreement is very good. With a good model in place, the work was extended in three ways. 1) Since measurements on full-scale equipment are difficult, scale modeling rules were developed and validated. 2) Two different numerical approaches were developed for evaluating the transmission loss of silencers taking into account the effect of higher order modes. 3) A power transfer matrix approach was developed to assess the acoustic performance of several duct components connected in series.

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Romano, Maria Cecilia. "Funções de Wannier para cristais fotônicos unidimensionais /." Bauru : [s.n.], 2011. http://hdl.handle.net/11449/99679.

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Orientador: Alexys Bruno Alfonso Banca: Ernesto Reyes Gómez Banca: Fabio de Jesus Ribeiro O programa de Pós graduação em Ciência e Tecnologia de Materiais, PosMat, tem carater institucional e integra as atividades de pesquisa em materiais de diversos campi da UNESP Resumo: Os cristais fotônicos são novos materiais em que a permissividade dielétrica e a permeabilidade magnética apresentam a periodicidade de uma rede de Bravais. No caso dos sólidos cristalinos, é a energia potencial de cada elétron que apresenta esse tipo de periodicidade. Por conta das semelhanças que existem entre as equações que descrevem os sintomas eletrônicos e fotônicos, muitos dos conceitos e métodos da teoria de estados eletrônicos vêm sendo aplicados na investigação de cristais fotônicos. Dentre esses conceitos, as funções de Wannier apresentam vantagens para o tratamento de estados eletrônicos e modos fotônicos localizados. Este trabalho aborda o caso de cristais fotônicos unidimensionais com simetria de inversão. Primeiramente são calculados e analisadas funções de Wannier bem localizadas. Em seguida são investigados os modos eletromagnéticos localizados produzidos por defeitos em cristais fotônicos, utilizando o método de matriz de transferência e o método da combinação linear das funções de Wannier. Finalmente, é feita a comparação dos resultados obtidos mediante esses métodos e são discutidas as vantagens do uso de funções de Wannier Abstract: Photonic crystal are new materials where both the dielectric permittivity and the magnetic permeability present the periodicity of a Bravais lattice. In the case of electronic states, this property is shown by the mono-eletronic potential energy. Due to the similarities between the eletronic and photonic problems, many concepts and methods of theory of electronic states are being applied to investigate photonic crystals. Among such concepts, the Wannier functions are advantageous to deal with either localized photonic modes. This work addresses the case of one-dimensional photonic crystals with inversion symmetry. First, well-localized Wannier functions are calculated and analyzed. Then, the localized modes produced by defects in photonic crystals are investigated by using either transfer matrices or linear combination Wannier functions. Finally, the results obtained by the two methods are compared and the advantages of using Wannier functions are discussed Mestre

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22

Jiang, Cui ling. "Transfert des pratiques de GRH dans les multinationales françaises : le cas des filiales françaises en Chine." Thesis, Pau, 2013. http://www.theses.fr/2013PAUU2005/document.

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Notre recherche porte sur les pratiques de GRH transférées par les maisons mères vers leurs filiales étrangères. Pour cela, nous étudions les impacts de trois niveaux de facteurs (pays, organisation et individus) affectant le processus de transfert des pratiques de GRH dans les multinationales. Nous vérifions l’effet des différences cultuelles, des interactions institutionnelles, du mode d’entrée et les rôles des expatriés sur ce transfert. Notre recherche repose sur l’étude de cas de huit filiales multinationales françaises implantées en Chine. Nos résultats montrent que les filiales françaises ont tendance à adopter massivement les pratiques des maisons mères. Plus que les différences culturelles, les interactions institutionnelles et les modes d’entrée déterminent le transfert des pratiques de GRH à l’international. En même temps, nous vérifierons les rôles des expatriés dans la procédure de transfert Our research investigates the transfer of HRM practices from parent companies to their overseas subsidiaries. We seek to figure out how three levels of factors (country, organization and individual) from host country affect the international transfer process. We identify the effects of cultures, institutional interactions, entry modes and expatriates on this transfer. Based on detailed case studies of the eight French MNCs in China, we explain how transfer of HRM practices is realized. Our empirical findings indicate that French subsidiaries tend to adopt home-country HRM practices to a considerable extent. More than cultural differences, institutional interactions and entry modes are the main restraints for the transfer of HRM practices. Meanwhile, we identify the role of expatriates in the transfer process

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23

Bourdais, Matthieu. "Etude critique des modes de cession applicables au fonds de commerce dans le cadre de la réalisation des actifs en liquidation judiciaire." Thesis, Lille 2, 2017. http://www.theses.fr/2017LIL20011/document.

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Depuis la réforme du droit des procédures collectives par la loi de sauvegarde des entreprises du 26 juillet 2005, deux régimes de cession aux conséquences juridiques dissemblables restent applicables lors des réalisations d’actifs en liquidation judiciaire. Le fonds de commerce, bien particulier à la définition lacunaire, présente la particularité d’être éligible tant à l’application du régime de la cession d’entreprise des articles L 642-1 et suivants du Code de Commerce, qu’à celle de la cession de biens isolés de l’article L 642-19 du Code de Commerce. Les éléments guidant la répartition des ensembles cédés sous l’un ou l’autre régime restent cependant à ce jour imprécis, compromettant la sécurité juridique des différents acteurs de la procédure. Suite à l’étude des causes théoriques et pratiques de cette confusion, des propositions de réforme de ces régimes peuvent être formulées afin d’offrir aux intervenants à la procédure, qu’ils soient parties à la cession, créanciers, ou salariés, une meilleure lisibilité de leurs droits et obligations Since the reform of the collective procedures by the July 26, 2005 Companies backup Act, two regimes of sales, of dissimilar legal consequences, can be applied during the divestments of the assets that takes place in the final stages of the judicial liquidation. The goodwill, specific asset of lacunar definition, has the particularity to be eligible both for the application of the system of transfer of companies mentionned at the article L 642-1, to that of isolated assets divestment regime mentionned at the article article L 642-19 of the French Commercial Code. Elements guiding the distribution of sets sold under one or the other regime remain however to this day unclear, compromising the legal security of the different actors in the process. Following the study of the theory and practice of this confusion causes, proposals for reform of these regimes can be formulated to provide to the participants in the proceedings, may they be parties to the sales, creditors or employees, a better readability of their rights and obligations

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Jayaraman, Veerappan, University of Western Sydney, and Faculty of Commerce. "A quantitative model for measuring technology transfer potentials at the industrial level - an application towards establishing technology cooperation." THESIS_FC_XXX_Jayaraman_V.xml, 1998. http://handle.uws.edu.au:8081/1959.7/122.

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International transfer of technology is the key element for the industrialisation and economic development of countries. But the success of any transfer depends on the judicious selection of appropriate technology from the right source and its effective absorption. This depends to a large extent on the selection, adaptation and assimilation capabilities of the recipient of the technology. In technology transfer, adaptation at the transferee end is an important stage. The difference between the technology levels of the transferor and transferee causes a technological gap which creates a potential for technology flow, but the transfer will depend on the assimilating capability of the transferee. In this study, a mathematical function that determines the technological level of a country is developed using the logistic growth pattern. The technological level of a country, in a given industry, is measured by an indicator called 'Technology Index' using the variables that influence and reflect the performance of that industry. The technology index is computed using the factor loadings obtained by the statistical technique factor analysis. In technology transfer, one of the most important problems facing countries is the selection of a transferor. Using the classical optimisation method, optimum transferors for various hypothetical transferees are determined in order to study the optimal partnership in technology transfer. A theoretical framework is provided for technological cooperation among the member countries of APEC based on the technology transfer model and classical optimisation method developed in this study. The theoretical framework can be applied to establish, for each industry, a technology cooperation network among the member countries by identifying the optimum partnership, that will provide an effective technology transfer process. Finally, based on the outcome of the research undertaken, conclusions are drawn and recommendations for further study presented Doctor of Philosophy (PhD)

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Chowdhury, Imran. "Scaling in social entrepreneurship : partnerships, knowledge transfer, and business models." Thesis, Cergy-Pontoise, Ecole supérieure des sciences économiques et commerciales, 2012. http://www.theses.fr/2012ESEC0002/document.

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L‟étude présentée ici tente d‟ouvrir une voie intermédiaire en s‟attachant au processus de transfert d‟innovation entre entrepreneurs sociaux. Nous appuyant sur la littérature sur la stratégie de transfert d‟innovation, qui cherche à développer une perspective globale des stratégies variées utilisées par les entreprises pour transférer des innovations efficacement, nous étudions ce processus de transfert dans un contexte d‟entrepreneuriat social, où l‟équilibre entre objectifs d‟efficience et objectifs sociaux plus larges est explicitement plus grand (Pache et Santos, 2010). Nous mettons ainsi en lumière le fait que certains organismes qui apparaissent et opèrent dans des contextes d‟échec simultané des marchés et des gouvernements axent leurs activités sur la création de valeur. S‟il est vrai que le transfert d‟innovation a le potentiel d‟ajouter de la valeur à toutes les entreprises, les divergences dans les objectifs organisationnels et les identités de celles-ci peuvent aboutir à des processus de transfert très différents, au fur et à mesure que l‟on passe de l‟entrepreneuriat commercial traditionnel à l‟entrepreneuriat social. Les travaux de recherche récents sur l‟entrepreneuriat social se sont centrés sur le besoin qu‟ont ces entrepreneurs d‟augmenter leur impact social en développant d‟avantage leurs opérations réussies (Bloom et Chatterji, 2009), mais le processus de transfert d‟innovations comme stratégie pour augmenter cet impact est mal connu. D‟autre part, la recherche sur le transfert d‟innovation ne s‟est quasiment pas penchée sur cette question, parce- qu‟elle n‟a pas envisagé comment des entrepreneurs qui veulent créer, et non capter, de la valeur s‟engagent dans le processus de transfert. L‟objectif de ce travail est d‟étudier comment les entrepreneurs sociaux gèrent le transfert d‟innovations et s‟organisent pour augmenter l‟impact de leurs innovations. Le sujet ne se limite donc pas aux mécanismes et aux résultats d‟un transfert, comme dans les études précédentes. Les questions posées ici ont pour but de comprendre comment les motivations des entrepreneurs sociaux, que l‟on considère comme différentes de celles des entrepreneurs plus traditionnels, influencent la façon dont se déroule le transfert d‟innovation. Pour ce faire, nous procédons d‟abord au réexamen des objectifs, du contexte, et du périmètre du transfert d‟innovations dans le cas d‟entreprises sociales The purpose of this dissertation is to deepen the study of social entrepreneurship by examining how social entrepreneurs use partnerships and organize themselves to transfer knowledge. My research takes a first step towards building a theory of innovation transfer and scaling for social entrepreneurship. This study builds on three primary foundations. One is the literature on innovation transfer strategy, which seeks to develop a broad view of the various strategies used by firms to transfer innovations effectively. The second is the literature on social entrepreneurship, which highlights the value-creation focus of certain firms that emerge and operate where situations of simultaneous market and government failure exist. Third, I use the literature on institutions, in particular institutional logics, to explain how organizational processes impacted by multiple logics unfold. Using an inductive, multiple-case methodology, I illuminate the innovation transfer process as it relates to social entrepreneurs. My objective is threefold. First, I aim to understand how social entrepreneurs manage the innovation transfer process. Second, I wan to identify the crucial factors influencing innovation transfer between social entrepreneurs, distinguish these factors from those observed in more traditional settings, and examine their impact on the direction of the innovation transfer process. Third, and finally, I hope to offer possible alternative views to the discussion on “scaling” in the social sector, a debate which has, to date, focused on “scaling organizations” as the primary means to expand the scope and reach of innovations developed by social entrepreneurs

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Zhang, Yang, and 張陽. "Nonlinear circuits modeling and analysis by the associated transform of Volterra transfer functions." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hdl.handle.net/10722/197528.

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Model order reduction (MOR) is one of the general techniques in the fields of computeraided design (CAD) and electronic design automation (EDA) which accelerates the flow of electronic simulations and verifications. By MOR, the original circuit, which is described by a set of ordinary differential equations (ODEs), can be trimmed into a much smaller reduced-order model (ROM) in terms of the number of state variables, with approximately the same input-output (I/O) characteristics. Hence, simulations using this ROM will be much more efficient and effective than using the original system. In this thesis, a novel and fast approach of computing the projection matrices serving high-order Volterra transfer functions in the context of weakly and strongly nonlinear MOR is proposed. The innovation is to carry out an association of multivariate Laplace-domain variables in high-order multiple-input multiple-output (MIMO) transfer functions to generate univariate single-s transfer functions. In contrast to conventional projection-based nonlinear MOR which finds projection subspaces about every si in multivariate transfer functions, only that about a single s is required in the proposed approach. This translates into much more compact nonlinear ROMs without compromising accuracy. Different algorithms and their extensions are devised in this thesis. Extensive numerical examples are given to prove and verify the algorithms. published_or_final_version Electrical and Electronic Engineering Doctoral Doctor of Philosophy

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Souza, Daniel. "Levantamento de mapas operacionais de transferência metálica para soldagem MIG/MAG de aço ao carbono na posição plana." Universidade Federal de Uberlândia, 2010. https://repositorio.ufu.br/handle/123456789/14853.

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The MIG/MAG process is nowadays the most important welding process. This is due to its high production capacity, characteristic searched by industries to improve their manufacturing processes. Thus, due to this process relevance, development of tools that helps to understanding how it works comes out as necessary, especially in relation to proper welding setting up. One tool for this task is the transfer mode map, which predicts the type of metal transfer according to the welding setting up. However, these maps, normally, are more scientific oriented rather that for practical purposes. In this context, the objective of this work was to map the transfer modes in such a way that welders, supervisors and engineers could be helped in the choice of the best setting up needed. For this purpose, a methodology was developed to provide more information than transfer modes according to the parameter setting up. The proposed mapping had the intention of obtaining transfer regions with proper operating characteristics (stable transfer resulting of appropriate welding conditions) and also information about weld bead conditions, production, thermal cycle and arc radiation. For each transfer mode looked for working at typical welding conditions, which mean that the contact tip-to-work distance was different for the two main transfer modes (short-circuit and spray). A large number of experiments was performed to map the transfers, with the objective to determine a stable operating regions of short-circuit and spray transfer mode using the ER70S-6 welding wire with three different shielding gases. After mapping, single-welded butt joint were carried-out using specific points of the maps instead of bead-on-plate. The proposed methodology was efficient in exterminating regions of operational stability, according to the experiments. It was also possible to have better welding geometries, in general, for setting ups within the map region of operational stability, but the results also depend on the shielding gas and the transfer mode. For setting ups outside the map region of operational stability the bead finish gets worse, except for spray transfer mode when working below the region of operational stability. The deposition efficiency is lower for setting ups outside the region and with gases containing higher levels of CO2, except for short-circuit transfer. The arc radiation intensity is lower in regions below the operational stability and higher above this position, but it is highly dependent of the arc length. Changes in the contact tip-to-work distance and/or in the power source inductance have no influence on the region of operational stability, except for short-circuit transfer, in which the contact tip-to-work distance is able to reduce the set voltage for this region. O processo de soldagem MIG/MAG é dos mais importantes processos de união de metais na atualidade. Isto se deve à sua alta capacidade de produção, característica constantemente cobiçada pelas indústrias em seus processos de fabricação. Assim, devido à relevância desse processo, torna-se necessária a construção de ferramentas que auxiliem no entendimento do funcionamento do mesmo, principalmente no que se refere à correta regulagem dos parâmetros de soldagem. Uma ferramenta utilizada para isto são os mapas de transferência metálica, que a partir dos parâmetros de regulagem, prevêem como resposta o tipo de transferência metálica. Porém, estes mapas, da forma que são normalmente confeccionados, são de caráter mais científico do que prático. Neste contexto, o objetivo deste trabalho foi a confecção de mapas de transferência práticos que venham auxiliar os usuários de soldagem (soldadores, supervisores e engenheiros) na escolha da melhor regulagem em função de suas necessidades. Para isto, foi desenvolvida uma metodologia que proporcionasse mais do que a informação sobre o tipo de transferência a partir da regulagem dos parâmetros. Nestes mapas propostos, objetivou-se obter uma região de transferência com característica operacional (transferência estável com condições de soldagem apropriadas) e também informações sobre o acabamento e perfil do cordão, rendimento de deposição, ciclo térmico e radiação emitida pelo arco. E para cada modo de transferência se procurou trabalhar apenas em condições típicas, o que fez com que a DBCP fosse diferenciada para dois modos principais de transferência (curto-circuito e goticular). Uma grande quantidade de experimentos foi realizada para mapear as transferências, com objetivo de delimitar uma região de estabilidade operacional de transferências por curto-circuito e outra goticular, utilizando o arame ER70S-6 e três gases de proteção para cada tipo de transferência. Após o levantamento, foram realizadas soldagens em pontos específicos dos mapas utilizando juntas ao invés de soldagem de cordão sobre chapa. Os resultados obtidos mostram que a metodologia proposta foi eficiente na determinação das regiões de estabilidade operacional. Mostraram também que o acabamento e a geometria do cordão, em geral, ficam melhores para regulagens dentro da região de estabilidade operacional, mas com resultados também dependentes do gás de proteção e tipo de transferência utilizada. Para regulagens fora da região de estabilidade operacional o acabamento piora, exceto para transferência goticular em regulagens abaixo da região. O rendimento de deposição é menor fora da região e com gases de proteção com maior teor de CO2, exceto para transferência por curto-circuito, onde, regulagens acima desta região não causam prejuízo. A intensidade de radiação emitida pelo arco é menor abaixo da região e maior acima desta, sendo dependente principalmente do comprimento de arco. A mudança da DBCP e da indutância da fonte não mostraram influência sobre a região de estabilidade operacional, exceto para transferência por curto-circuito, onde a DBCP promove a diminuição da regulagem das tensões desta região. Mestre em Engenharia Mecânica

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Al, Hajri Abdullah Said Mechanical &amp Manufacturing Engineering Faculty of Engineering UNSW. "Logistics technology transfer model." Publisher:University of New South Wales. Mechanical & Manufacturing Engineering, 2008. http://handle.unsw.edu.au/1959.4/41469.

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A consecutive number of studies on the adoption trend of logistics technology since 1988 revealed that logistics organizations are not in the frontier when it comes to adopting new technology and this delayed adoption creates an information gap. In the advent of supply chain management and the strategic position of logistics, the need for accurate and timely information to accompany the logistics executives became more important than ever before. Given the integrative nature of logistics technology, failure to implement the technology successfully could result in writing off major investments in developing and implementing the technology or even in abandoning the strategic initiatives underpinned by these innovations. Consequently, the need to employ effective strategies and models to cope with these uncertainties is rather crucial. This thesis addresses the aspect of uncertainty in implementation success by process and factor research models. Process research approach focuses on the sequence of events in the technology transfer process that occurs over time. It explains the story that explains the degree of association between these sequences and implementation success. Through content analysis, this research gathers, extracts, and categorizes process data of actual stories of logistics technology adoption and implementations in organizations that are published in literature. The extracted event sequences are then analyzed using optimal matching from natural science and grouped using cluster analysis. Four patterns were revealed that organizations follow to transfer logistics technology namely, formal minimalist, mutual adaptation, development concerned, and organizational roles dispenser. Factors that contribute to successful implementation in each pattern were defined as the crucial and necessary events that characterized and differentiated each pattern from others. The factor approach identifies the potential predictors of successful technology implementation and tests empirical association between predictors and outcomes. This research develops a logistics technology success model. In developing the model, various streams of research were investigated including logistics, information systems, and organizational psychology. The model is tested using a questionnaire survey study. The data were collected from Australian companies which have recently adopted and implemented logistics technology. The results of a partial least squares structured equation modeling provide strong support for the model constructs and valuable insights to logistics/supply chain managers. The last study reports a convergent triangulation study using multiple case study of three Australian companies which have implemented logistics technology. A within and a cross case analysis of the three cases provide cross validation for the results of the other two studies. The results provided high predictive validity for the two models. Furthermore, the case study approach was so beneficial in explaining and contextualizing the linkages of the factor-based model and in confirming the importance of the crucial events in the process-based model. The thesis concludes with a research and managerial implications chapter which is devoted for logistics/supply chain managers and researchers.

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Shankaran, Rajan, University of Western Sydney, and School of Computing and Information Technology. "Asynchronous transfer mode security." THESIS_XXX_CIT_Shankaran_R.xml, 1999. http://handle.uws.edu.au:8081/1959.7/252.

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There is a growing interest in the development of broadband services and networks for commercial use in both local area and wide area networks. The primary reasons for this is a pressing need to meet the demand for increased bandwidth for remote sites interconnection, and in high speed data transfer of bulk data such as images etc. There has also been a significant change in the characteristics of network traffic. It is increasingly taking the form of bursty traffic characterized by an unpredictable demand for bandwidth of several megabytes. A new generation of networking technologies have emerged to meet the demand of growing and uncertain bandwidth requirements. One such technology is called Asynchronous Transfer Mode (ATM) for use on broadband networks under the banner of broadband ISDN. ATM enables interconnection at high speeds in the range of Mbit/s or Gbit/s over wide areas, which effectively moves the bottleneck from networks to end systems. Furthermore, the user is able to access bandwidth on demand and the user is only charged for the bandwidth actually used. As more and more information (audio, image and data) is transferred over ATM networks, security issues are becoming increasingly critical. The rapidly growing use of the Internet to transfer confidential and sensitive information only enhances the importance of security services. One may even argue that the success of ATM will be determined not by its cost effectiveness but also to the level of trust that can be placed on its performance, security and availability. The objective of this dissertation is to address the issues involved in the design of security services for ATM networks. Master of Science (Hons)

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Shankaran, Rajan. "Asynchronous transfer mode security." Thesis, View thesis, 1999. http://handle.uws.edu.au:8081/1959.7/252.

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There is a growing interest in the development of broadband services and networks for commercial use in both local area and wide area networks. The primary reasons for this is a pressing need to meet the demand for increased bandwidth for remote sites interconnection, and in high speed data transfer of bulk data such as images etc. There has also been a significant change in the characteristics of network traffic. It is increasingly taking the form of bursty traffic characterized by an unpredictable demand for bandwidth of several megabytes. A new generation of networking technologies have emerged to meet the demand of growing and uncertain bandwidth requirements. One such technology is called Asynchronous Transfer Mode (ATM) for use on broadband networks under the banner of broadband ISDN. ATM enables interconnection at high speeds in the range of Mbit/s or Gbit/s over wide areas, which effectively moves the bottleneck from networks to end systems. Furthermore, the user is able to access bandwidth on demand and the user is only charged for the bandwidth actually used. As more and more information (audio, image and data) is transferred over ATM networks, security issues are becoming increasingly critical. The rapidly growing use of the Internet to transfer confidential and sensitive information only enhances the importance of security services. One may even argue that the success of ATM will be determined not by its cost effectiveness but also to the level of trust that can be placed on its performance, security and availability. The objective of this dissertation is to address the issues involved in the design of security services for ATM networks.

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Shankaran, Rajan. "Asynchronous transfer mode security /." View thesis, 1999. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20030616.142410/index.html.

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Thesis (M. Sc.) (Hons.) -- University of Western Sydney, Nepean, 1999. Thesis submitted in fulfilment of the requirements for the award of the degree Master of Science (Honors) from the University of Western Sydney, Nepean, School of Computing and Information Technology. Bibliography : p. 87-88.

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Walker, Christina H. "Monte Carlo radiation transfer studies of protoplanetary environments." Thesis, University of St Andrews, 2007. http://hdl.handle.net/10023/218.

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Monte Carlo radiation transfer provides an efficient modelling tool for probing the dusty local environment of young stars. Within this thesis, such theoretical models are used to study the disk structure of objects across the mass spectrum - young low mass Brown Dwarfs, solar mass T-Tauri stars, intermediate mass Herbig Ae stars, and candidate B-stars with massive disks. A Monte Carlo radiation transfer code is used to model images and photometric data in the UV - mm wavelength range. These models demonstrate how modelling techniques have been updated in an attempt to reduce the number of unknown parameters and extend the diversity of objects that can be studied.

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Zhang, Hongbin 1965. "A model radiative transfer problem." Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/277071.

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The analytical solution to a model time-dependent continuous lethargy photon transport equation is evaluated numerically to obtain a benchmark solution using the Laplace transforms coupled with the multiple collision expansion method. The benchmark solution is then used to check the accuracy of the multigroup approximation. Excellent agreement between continuous lethargy benchmarks and multigroup approximation is obtained.

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Santos, Ãngelo Fernandes Moreno dos. "Analysis of transfer of value added tax - vaf in transfers to the icms municipalities in cearÃ." Universidade Federal do CearÃ, 2012. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=10179.

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nÃo hÃ This study aims to analyze the transfer of the Value Added Tax (VAF) in the transfer of resources from ICMS to municipalities in CearÃ stipulates as the Federal Constitution of 1988 and the Supplementary Law No. 63 of 1990. The research will include the period from 2003 to 2010 of all 184 municipalities of CearÃ and used in data analysis, the econometric model for panel data. With this model, we sought to determine how the independent variables Bolsa Familia, FPM, GDP, Complementary Law No. 86/97 and CIDE influence the dependent variable (VAF). The results show that the explanatory variables in a positive impact in increasing the transfer of the VAF for the municipalities of CearÃ. The variable that was most significant was the Complementary Law No. 86/97, created with the intent to waive the collection of the tax ICMS products and services for export, so the VAF provides an increase in the transfer to the municipalities about 7.47% when there is an increase of its exports. Este estudo tem como objetivo analisar o repasse do Valor Adicionado Fiscal (VAF) na transferÃncia dos recursos do ICMS devido aos municÃpios cearenses conforme preceitua a ConstituiÃÃo Federal de 1988 e a Lei Complementar nÂ 63 de 1990. A pesquisa compreenderÃ o perÃodo de 2003 a 2010 de todos os 184 municÃpios cearenses e utilizou-se, na anÃlise dos dados, o modelo economÃtrico de dados em painel. Com esse modelo, buscou-se verificar como as variÃveis independentes Bolsa FamÃlia, FPM, PIB, Lei Complementar nÂ 86/97 e CIDE influenciam na variÃvel dependente (VAF). Os resultados demonstram que as variÃveis explicativas impactam de forma positiva no aumento do repasse do VAF para os municÃpios cearenses. A variÃvel que se apresentou mais significativa foi a Lei Complementar nÂ 86/97, criada com o intuito de isentar da cobranÃa do tributo ICMS os produtos e serviÃos destinados Ã exportaÃÃo, portanto, o VAF proporciona um aumento no repasse para os municÃpios de cerca de 7,47% quando hÃ um aumento de suas exportaÃÃes.

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Mate, de Gerando Anastasie. "Study of the Neuron-Astrocyte Relationship in a Rodent Model of Tauopathy." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS298.

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Les Tauopathies sont un ensemble de maladies neurodégénératives caractérisées par l’agrégation de la protéine Tau dans les neurones, astrocytes et autres types cellulaires. Toutefois, les mécanismes sous-tendant la présence de Tau dans les astrocytes et les conséquences de Tau sur les astrocytes restent peu connus. L’objectif de ce projet a été d’étudier l’interaction entre les neurones porteurs de Tau soluble et/ou agrégée et les astrocytes avoisinants. Nous avons généré trois modèles de Tauopathie par transfert de gènes et avons caractérisé la pathologie Tau neuronale et astrocytaire par histologie et biologie moléculaire. Dans l’hippocampe, la surexpression de l’isoforme mutante hTAUP301L ou d’une forme pro-agrégeante hTAUProAggr, mais pas celle de la protéine sauvage hTAUWT, a entraîné la formation progressive d’agrégats aussi bien dans les neurones que dans les astrocytes. Nous avons montré que les inclusions astrocytaires de Tau étaient secondaires à une pathologie neuronale par différents schémas expérimentaux. En utilisant des vecteurs spécifiques de types cellulaires, nous avons également démontré le transfert bi-directionnel d’espèces de Tau entre neurones et astrocytes. Curieusement, nous avons observé une perte astrocytaire uniquement dans le subiculum du groupe hTAUWT qui ne présente pas d’inclusions astrocytaires de Tau. Nos données ont montré que, dans nos modèles, la tauopathie astrocytaire est secondaire à la présence de dégénérescences neurofibrillaires et ne résulte pas d’une agrégation liée à une surexpression réactionnelle de Tau endogène dans l’astrocyte. De plus, des amorces de Tau neuronales peuvent promouvoir l’agrégation de Tau astrocytaire et la Tau astrocytaire peut être transférée aux neurones. Par ailleurs, si les agrégats de Tau paraissent plutôt bénins pour les astrocytes, les conséquences fonctionnelles d’une telle astrogliopathie restent encore à évaluer Tauopathies are neurodegenerative diseases characterized by the aggregation of Tau protein in neurons, astrocytes and other cell types. However, the mechanisms leading to the presence of Tau aggregates in astrocytes and the consequences of Tau on astrocytes are poorly understood. The aim of this project was to study the relationship between neurons bearing soluble and/or aggregated Tau species and their neighboring astrocytes.We thus generated three gene transfer-based Tauopathy models and used immunohistological and molecular biology methods to characterize Tau pathology in neurons and astrocytes.In the hippocampus, overexpression of mutant hTAUP301L or that of a pro-aggregating variant hTAUProAggr, but not that of wild-type Tau hTAUWT, led to a gradual increase in the formation of aggregates not only in neurons but also in astrocytes. Using different experimental paradigms, we showed that astrocytic Tau was secondary to neuronal pathology. Using cell type-specific AAV- Tau vectors, we further demonstrated the bi-directional transfer of Tau species between neurons and astrocytes. Interestingly, we observed astrocyte loss in the subiculum only in the hTauWT group in the absence of any astrocytic Tau inclusions.Our data show that astroglial tauopathy is secondary to the presence of neurofibrillary tangles in our models and does not result from aggregation of overexpressed endogenous Tau in astrocytes. In addition, neuronal Tau seeds can promote the aggregation of astrocytic Tau and astrocytic Tau can be transferred to neurons. Furthermore, if Tau aggregates appear fairly innocuous for astrocytes, the functional consequences of such astroglial tauopathy still remain to be further assessed

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Carney, Cameron P., and Tony L. Ellis. "Transition to asynchronous transfer mode (ATM) an implementation model for NPS software metrics lab." Thesis, Monterey, California ; Naval Postgraduate School, 1999. http://hdl.handle.net/10945/13586.

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With Asynchronous Transfer Mode (ATM), we are experiencing the emergence of a network technology that has the potential of satisfying the requirement for a worldwide standard to allow interoperability of information, regardless of the hosts or type of information. Historically ATM has been advertised as a Wide Area Network (WAN) technology. Recently, we have seen ATM take on more applications in the local area environment competing with the standard LAN technology, Ethernet. With its ability to accommodate the simultaneous transmission of data, voice. and video. ATM could potentially create a seamless network based on one standard. As a switched-based technology, some of the benefits provided by ATM are dedicated bandwidth per connection, higher aggregate bandwidth, flexible access speeds, reduced network bandwidth cost. reduced network access costs, reduced equipment cost and commitment, and improved management and flexibility. We provide a discussion of the ATM standard an evaluation of the SML's LAN architecture, and propose three ATM implementation models using the SML that NPS could employ to provide ITM students with practical experience and exposure to this technology. Each model outlines the specifications (i.e. hardware and software) required for implementation.

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Seguin, Lisa (Lisa Marie) Carleton University Dissertation International Affairs. "Technology transfer: four models of management transfer from Canada to China." Ottawa, 1989.

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Lucchetti, Aurélie. "Modélisation et conception d'un système de culture de microalgues." Thesis, Paris, ENMP, 2014. http://www.theses.fr/2014ENMP0048/document.

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Les microalgues sont de plus en plus regardées pour leurs potentiels énergétiques et leurs nombreuses applications. Mais les systèmes de production actuels, que se soit les systèmes dits ouvert comme les bassins ou les systèmes fermés, appelés photobioréacteurs, sont très énergivores et pas assez productifs. Cette thèse propose un nouveau concept de photobioréacteur, composé d'un airlift et d'une plaque mince. Le photobioréacteur est caractérisé expérimentalement et est modélisé sous plusieurs aspects. L'hydrodynamique du système est modélisée pour prédire le comportement des fluides dans le système. Les phénomènes de transferts de masse sont modélisés par le modèle des deux films. La modélisation permet de connaitre l'apport minimum nécessaire en dioxyde de carbone pour la culture des microalgues et permet d'évaluer la concentration en oxygène dissous dans le photobioréacteur. Elle permet aussi d'évaluer son élimination par le système, l'oxygène étant inhibant pour la culture. Les phénomènes de transferts de chaleur sont aussi modélisés, permettant de connaitre l'impact des différents paramètres (ensoleillement, température de l'air ambiant) sur la température de culture. Ces différents modèles sont rassemblés en un modèle global qui est comparé aux résultats expérimentaux de culture d'algues. Le modèle global est ensuite utilisé dans un contexte plus complexe : l'intégration des plaques minces du photobioréacteur aux parois d'un bâtiment. Le modèle global permettra d'étudier l'effet les différentes orientations (Nord, Sud, Est, Ouest en vertical sur les façades et à l'horizontal sur les toits) sur les températures et productivité du système. La consommation d'énergie de la culture est optimisée grâce au modèle. A la suite de cette optimisation, certaines perspectives sur l'intégration énergétique d'un tel système sont proposées Microalgae are more and more studied for their energy potential and various applications. However, the actual production processes (open and closed photobioreactor) use a lot of energy and aren't productive enough. This thesis presents a novel process of microalgae culture, with an airlift system coupled to a thin plate. The photobioreactor is experimentally characterized and modeled for many aspects. Hydrodynamics of the system is modeled to predict the fluid behavior in the system. Mass transfers are modeled using the two film model. The model allows knowing minimum carbon needs for microalgae culture. It also allows evaluating dissolved oxygen concentration in the photobioreactor and its elimination efficiency. Oxygen is inhibiting the culture at high concentration. Heat transfers are also modeled, allowing to know climate parameters impact (sunshine, ambient air temperature) on culture temperature. All models are assembled in a global model. This model is compared to microalgae culture experimental results. Finally, the global model is used to study a more complex system: culture thin plates are integrated on the walls of buildings. Global model allow studying different orientation effects on temperature and productivity of the system. Culture is optimized for energy consumption and some perspectives on energy integration of such a system are proposed

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Hachfi, Fakhreddine Mohamed. "Future of asynchronous transfer mode networking." CSUSB ScholarWorks, 2004. https://scholarworks.lib.csusb.edu/etd-project/2639.

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The growth of Asynchronous Transfer Mode (ATM) was considered to be the ideal carrier of the high bandwidth applications like video on demand and multimedia e-learning. ATM emerged commercially in the beginning of the 1990's. It was designed to provide a different quality of service at a speed up 100 Gbps for both real time and non real time application. The turn of the 90's saw a variety of technologies being developed. This project analyzes these technologies, compares them to the Asynchronous Transfer Mode and assesses the future of ATM.

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Viala, Diego. "Étude de la physique de l'allumage par choc." Electronic Thesis or Diss., Bordeaux, 2024. http://www.theses.fr/2024BORD0127.

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Une décennie d'expériences au "National Ignition Facility" a démontré que la fusion par confinement inertiel constitue une approche crédible pour la production d'énergie, avec des résultats allant au-delà du régime d'allumage. Cependant, l'approche par attaque indirecte se révèle inadéquate pour les implosions à gain élevé et une production d'énergie fiable. L'option d'allumage par attaque directe est privilégiée en raison de ses conceptions de cible plus simples et de son meilleur couplage énergétique. Actuellement, aucune installation laser à l'échelle d'allumage n'est configurée selon l'approche directe standard, posant ainsi un défi à relever. Les expériences intégrées d'allumage par attaque directe se sont principalement concentrées sur la compréhension de la physique à des échelles réduites, dans le but ultime de démontrer la nécessité et la faisabilité de construire une installation laser internationale dédiée à l'attaque directe.Ce manuscrit de thèse présente une étude approfondie sur la validation de codes d'hydrodynamique radiative 3D à l'état de l'art, ainsi que sur la compréhension des bas modes d'éclairement laser et du couplage laser-cible, jouant un rôle crucial dans la fusion par confinement inertiel. L'examen attentif des modèles de CBET revêt une importance capitale dans ce contexte, assurant la précision des simulations et contribuant à la conception des futures installations à attaque directe. De plus, l'investigation de l'homogénéité du laser sur la cible est impérative pour appréhender son impact global sur le système A decade of experiments at the National Ignition Facility has proven that inertial confinement fusion is a credible approach to energy production, with experiments having exceeded the ignition regime. However, the indirect-drive approach is not suited for high gain implosions and reliable energy production. The direct-drive ignition approach is favoured for energy production as it features simpler target designs and couples more energy to them. There are currently no ignition-scale laser facilities configured for the standard direct-drive approach. Integrated direct-drive experiments have mostly been focused on understanding the physics at reduced scales, with the ultimate goal of demonstration of necessity and feasibility of construction of an international direct-drive laser facility.This thesis manuscript presents a study on the validation of state-of-the-art 3D radiative hydrodynamics codes and the understanding of low modes and laser coupling which play crucial roles in the study of inertial fusion energy. Careful examination of CBET models is of paramount importance in this context, ensuring the accuracy of simulations and contributing to the design of future direct-drive facilities. In addition, the investigation of laser homogeneity on target is imperative to understand its overall impact on the system

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Luo, Gang. "A cloud fraction and radiative transfer model." Diss., Georgia Institute of Technology, 1990. http://hdl.handle.net/1853/25753.

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Maehle, Valerie A. "Conceptual models in the transfer of learning." Thesis, University of Aberdeen, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.261454.

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In order to attain clinical competence student physiotherapists apply knowledge from a range of cognitive domains in the assessment and treatment of patients with a variety of conditions. Current research indicates that the ability to transfer knowledge to a wide variety of conditions requires a cognitive structure in which concepts are embedded in a rich network of interconnections (Faletti, 1990, Spiro, 1987). A concept mapping technique was selected as means of eliciting a representation of the knowledge the student possessed and would access in order to underpin the assessment and treatment of a specific peripheral joint condition. Twenty second and third year physiotherapy students currently on clinical placement in an Out-Patient Department each produced a concept map prior to assessing the patient. A modification of the 'Student Teacher Dialogue' (Hammond et al, 1989) was the methodology selected for identification of the transfer of learning. Analysis of the transcription of this interaction provided evidence of the domain specific and procedural knowledge transferred to the patient assessment. Weak correlations were found to exist between the degree of complexity of the concept map the student produced and the amount and level of transfer achieved in the clinical setting. Also there was evidence to suggest that abstract subject areas, or those which involved practical or clinical applications, facilitated the development of more concentrated conceptual networks. However, contrary to expectation, third year students failed to produce higher quality maps than second year students, despite having greater academic and clinical experience.

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Kelly, Luke. "A stochastic Dollo model for lateral transfer." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:6884785c-fccc-4044-b5b2-7a8b7015b2a5.

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Lateral transfer, a process whereby species exchange evolutionary traits through non-ancestral relationships, is a frequent source of model misspecification in phylogenetic inference. Lateral transfer obscures the phylogenetic signal in the data - the signal of the taxa ancestry - as the histories of affected traits are mosaics of the species phylogeny and may conflict with the underlying phylogeny. We control for the effect of lateral transfer in a Stochastic Dollo model and a Bayesian setting. We infer rooted phylogenetic trees. Our likelihood is highly intractable as its parameters are given by the solution of a sequence of systems of differential equations which represent the expected evolution of traits along a tree and grow exponentially in dimension with the number of taxa under consideration. We construct an accurate parameter approximation framework, and from this we derive an efficient exact-approximate inference scheme. We illustrate our method on data sets of lexical traits in Eastern Polynesian and Indo-European languages and obtain improved fits over the corresponding model without lateral transfer.

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Rea, Tracy. "A talent transfer lifecycle model in sport." Thesis, University of Stirling, 2018. http://hdl.handle.net/1893/28842.

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This thesis focussed on examining the talent transfer experiences as lived by the athletes whom went through transitions. The purpose was to examine why athletes chose to continue in their pursuit of international competition by switching sports as well as understanding how they managed the process and their own unique experiences. Talent transfer is a process occurring when an athlete ceases or reduces their involvement in a sport in which they have invested significant time and concentrates their efforts in a sport that is new to them but involving similar skills. The process comprises of athletes who might be able to perform if fast tracked into other sports with sporting organisations seeing the benefits of this alternative talent identification (TID) system with specific examples of success. The first study (chapter 3) examined the athletes' experiences through the transition of talent transfer. Ten athletes were interviewed: five from a supported talent transfer programme (UK Sport/National Governing Body: NGB); and five that went through the process of their own accord (informally). The purpose of the second study (chapter 4) was to examine the subjective experiences and one athlete's meaning of the talent transfer process, who moved from judo to cycling and internationally medalled in both. A life history was chosen as the methodology in which to convey the information gathered through the process. The purpose of the third study (chapter 5) was to explore 10 purposeful athletes' experiences of the talent transfer process to understand their unique experiences within a supported NGB programme through unstructured interviews. The results from all three studies are discussed and culminate in a model of the talent transfer process (chapter 6) with limitations and future research directions also discussed. In conclusion, the findings offer a unique examination into athletes' experiences through the Talent Transfer Lifecycle Model.

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Boyer, Sebastien (Sebastien Arcario). "Transfer learning for predictive models in MOOCs." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/104832.

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Thesis: S.M. in Technology and Policy, Massachusetts Institute of Technology, School of Engineering, Institute for Data, Systems, and Society, Technology and Policy Program, 2016. Thesis: S.M., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2016. Cataloged from PDF version of thesis. Includes bibliographical references (pages 85-87). Predictive models are crucial in enabling the personalization of student experiences in Massive Open Online Courses. For successful real-time interventions, these models must be transferable - that is, they must perform well on a new course from a different discipline, a different context, or even a different MOOC platform. In this thesis, we first investigate whether predictive models "transfer" well to new courses. We then create a framework to evaluate the "transferability" of predictive models. We present methods for overcoming the biases introduced by specific courses into the models by leveraging a multi-course ensemble of models. Using 5 courses from edX, we show a predictive model that, when tested on a new course, achieved up to a 6% increase in AUCROC across 90 different prediction problems. We then tested this model on 10 courses from Coursera (a different platform) and demonstrate that this model achieves an AUCROC of 0.8 across these courses for the problem of predicting dropout one week in advance. Thus, the model "transfers" very well. by Sebastien Boyer. S.M. in Technology and Policy S.M.

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Liang, Kelly (Kelly JieRu). "Optimized transfer-pricing model for Asia Pacific." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/68894.

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Thesis (M. Eng. in Logistics)--Massachusetts Institute of Technology, Engineering Systems Division, 2011. Cataloged from PDF version of thesis. Includes bibliographical references (p. 35). Transfer price is an important field of study for profit maximization. As more multinational enterprises (MNEs) are involved in global trading in the recent decades, the objective to set an optimized transfer price is more crucial than ever since the difference in tax rates and tariffs have sophisticated impacts on the overall profit for the corporation. In this thesis, which focuses primarily on Asia Pacific, I will review historical transfer pricing methods, explore the factors that affect transfer price determination, and construct a mathematical model to determine the optimal transfer price by comparing and contrasting the different transfer pricing methods with data from a hypothetical company. Particularly, I will illustrate the effects of taxes and tariffs on the determination of transfer price. Consequently, I will perform sensitivity analysis with respects to tariffs, taxes, and shipping costs. The thesis will conclude with recommendations on the optimized transfer pricing methods and insights on the implications for the method. by Kelly Liang. M.Eng.in Logistics

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Kawesha, David Mukuma. "A mass transfer model for structured packing." Thesis, Stellenbosch : Stellenbosch University, 2002. http://hdl.handle.net/10019.1/52647.

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Thesis (MScEng) -- Stellenbosch University , 2002. ENGLISH ABSTRACT: The distillation process is the most widely used separating process in the chemical process industry. The optimal design of the distillation units can lead to reduced capital costs and improved energy utilisation. This is particularly the case for structured packed distillation column where design methods tend to over-predict the column efficiency. This work seeks to contribute to the development of a reliable mass transfer model for structured packing. A gas phase mass transfer correlation was developed based on the evaporation of pure components into an air stream. The mass transfer rates were measured in a short triangular wetted wall channel with a corrugated surface wall. The influence that the geometric configuration as well as surface structure has on the mass transfer rates was investigated. The channel geometry and surface wall structure resembled that of the structured packing (Flexipac 350Y). The influence of the channel geometry on the gas mass transfer rates was not significant except at low flow conditions. The liquid phase resistance was investigated for binary mixtures in the triangular wetted wall channel. It was found that the overall mass transfer rate decreased with increasing composition of the volatile component. The enhancement of the gas phase mass transfer rate masked the presence of the liquid resistance. ii The gas phase mass transfer correlations were used in the mass transfer model to predict the separation efficiency of a structured packed distillation column. The structured packing used to validate the mass transfer model was high-capacity Flexipac 350Y and normal Flexipac 350Y. The binary distillation experiments were done at total reflux conditions for the pressure range O.33-1atm. The accuracy of the separation efficiencies of the mass transfer model improved with increasing pressure for both materials. The mass transfer model was able to predict the variation of separation efficiencies with column loadings. AFRIKAANSE OPSOMMING: Distillasie is die skeidingsmetode wat die meeste in die chemiese industrie gebruik word. Die optimale ontwerp van distillasie eenhede kan lei tot verlagings in kapitaalkostes en 'n verbeterde gebruik van energie. Dit is veral waar in die geval van kolomme met gestruktureerde pakking waar huidige ontwerpsmetodes, die kolomeffektiwiteit nie akkuraat beskryf nie. Hierdie studie het ten doelom 'n bydrae te lewer tot die ontwikkeling van 'n betroubare massa-oordragsmodel vir gestruktureerde pakking. 'n Gasfase massa-oordragskorrelasie is ontwikkel gebaseer op metings van die verdampingstempo van suiwer komponente in 'n lugstroom. Die massaoordragstempos is gemeet in 'n kort driehoekige benatle wand kanaal waarin die wand 'n bepaalde oppervlakprofiel het. Die invloed van beide die kanaalgeometrie en die oppervlakprofiel is ondersoek. Die geometrie en oppervlakprofiel is soorgelyk aan die van Flexipac 350Y gestruktureerde pakking. Die invloed van die kanaalgeometrie op die gasfase massaoordragstempos is slegs beduidend by lae vloeitempos. Die vloeistoffase weerstand vir binêre mengsels is ondersoek in die driehoekige kanaal. Dit is gevind dat die algehele massa-oordragstempo verlaag met 'n verhoging in die konsentrasie van die vlugtige komponent. Die verhoging in die gasfase massa-oordragstempo verberg die invloed van die vloeistoffase weerstand. Die gasfase massa-oordragskorrelasies is in 'n massa-oordragsmodel gebruik om die skeidingseffektiwiteit van gestruktureerde pakking in "n kolom te voorspel. Metings op hoë-kapasiteit Flexipac 350Y en normale Flexipac 350Y is gebruik om die modelvoorspellings te evalueer. Die binêre distillasies is by totale terugvloei gedoen in die drukbereik 0.33 - 1.0 atm. Daar is gevind dat die model meer akkuraat is by hoër drukke. Die massa-oordragsmodel is in staat om die variasie in skeidingseffektiwiteit met veranderende kolomlading te voorspel.

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Schlawin, Everett A. "Radiative Transfer Models of the Galactic Center." Oberlin College Honors Theses / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=oberlin1249300204.

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Graca, Guilherme C. C. Carrilho da. "Simplified models for heat transfer in rooms /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2003. http://wwwlib.umi.com/cr/ucsd/fullcit?p3112829.

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Thome, Kurtis John. "Radiative transfer model for a spherical atmosphere." Diss., The University of Arizona, 1990. http://hdl.handle.net/10150/185288.

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A new model for computing radiative transfer in a spherically symmetric atmosphere has been developed which uses a Gauss-Sidel iteration similar to Herman(1963). To account for inhomogeneities in the horizontal intensity field, the current work introduces a conical boundary on which solutions are found. This boundary is used in an interpolation scheme to obtain the intensity at the center of the cone. The model includes absorption and aerosols but neglects polarization and refraction. Checks of the model were performed. Results for a high sun and small optical depth compared to flat atmosphere results were consistent with geometric arguments. The results where the radius of the planet was increased by a factor of 100 agree with flat atmosphere results to better than 1%. Flux is conserved to better than 3%, and boundary solutions are accurate to better than 3% for nontangent paths, and 12% for tangent paths. A 10% biased boundary solution caused less than a 1% change in the final solution. The model also agreed favorably with models developed by Asous (1982), Marchuk et al. (1980) and Adams and Kattawar (1978). From the results of tests the model is concluded to be accurate to 3%, and in most earth-atmosphere situations accurate to 1%. This accuracy is on the order of, or better than, previous techniques and more computationally efficient than Monte Carlo simulations. The current model is more versatile and accurate than techniques that strive for computational efficiency. The model was used to examine the atmospheric limb problem and results from this work indicate that ozone and stratospheric dust layers may be detected from limb measurements.

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Dissertations / Theses on the topic 'Modes of Transfer'

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