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Rodríguez, Cepeda Juan Pablo. "Modelatge multimodal de transicions i asimetries en línies three-line-microstrip." Doctoral thesis, Universitat Ramon Llull, 2010. http://hdl.handle.net/10803/9142.
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Una línia de transmissió three-line-microstrip consisteix en tres pistes paral·leles practicades sobre la cara d'un dielèctric amb un pla de massa inferior. La propagació en aquesta línia es pot descriure en termes de tres modes fonamentals anomenats ee, oo i oe. Tot i que aquests modes són ortogonals interaccionen entre sí a qualsevol transició, discontinuïtat o asimetria. En el pla d'una transició o asimetria es genera un intercanvi d'energia o conversió modal en el que prenen part tots els modes.En aquest treball s'analitza la conversió modal que s'origina en un conjunt de transicions i asimetries construïdes sobre línies three-line-microstrip. L'estudi es realitza aplicant la tècnica de l'anàlisi multimodal. L'ús d'aquesta tècnica permet la deducció d'una sèrie de models multimodals (un per a cada transició) que proporcionen una anàlisi simple, rigorosa i quantitativa d'aquest fenomen.
La validesa d'aquest estudi es verifica de manera experimental. Els bons resultats obtinguts demostren que els models multimodals proposats prediuen de manera precisa el comportament de les transicions. Aquest fet permet el seu ús per analitzar circuits o estructures constituïts per trams de tres pistes acoblades. En el cas d'aquesta tesi, han estat aplicats als camps de l'EMC i de les microones. Pel que fa a l'EMC, s'ha realitzat un estudi de l'acoblament i la integritat del senyal en configuracions de PCB amb trams de tres pistes acoblades. Aquest estudi ha permès identificar les transicions i asimetries en aquests circuits com a possibles fonts d'interferència i de degradació dels senyals ja que la conversió modal es pot interpretar com a un procés d'interferència que involucra tots els senyals presents. Pel que fa a les microones, s'ha realitzat una anàlisi multimodal de filtres spurline. Aquesta anàlisi ha permès desenvolupar dues noves estructures, la principal característica de les quals és la seva compacitat que, a diferència d'altres estructures similars, s'aconsegueix permetent la presència d'un nou mode en el procés de ressonància. L'ús dels models multimodals per a l'anàlisi d'aquestes estructures ha permès una interpretació clara i senzilla del seu funcionament així com el desenvolupament d'una sèrie de regles de disseny que permeten un ajust fàcil i ràpid de certs paràmetres dels filtres com ara la freqüència central i l'ample de banda.
Una línea de transmisión three-line-microstrip consiste en tres pistas paralelas practicadas sobre la cara de un dieléctrico con un plano de masa inferior. La propagación en esta línea se puede describir en términos de tres modos fundamentales llamados ee, oo i oe. Aunque estos modos son ortogonales interaccionan entre se en cualquier transición, discontinuidad o asimetría. En el plano de una transición o asimetría se genera un intercambio de energía o conversión modal en el que toman parte todos los modos.
En este trabajo se analiza la conversión modal que se origina en un conjunto de transiciones i asimetrías construidas sobre líneas three-line-microstrip. El estudio se realiza aplicando la técnica del análisis multimodal. El uso de esta técnica permite la deducción de una serie de modelos multimodales (un per a cada transición) que proporcionan un análisis simple, riguroso i cuantitativo de este fenómeno.
La validez de este estudio se verifica de manera experimental. Los buenos resultados obtenidos demuestran que los modelos multimodales propuestos predicen de manera precisa el comportamiento de las transiciones. Este hecho permite su uso para analizar circuitos o estructuras constituidos por tramos de tres pistas acopladas. En esta tesis doctoral, han sido aplicados a los campos de la EMC i de las microondas. En el primero de ellos, se ha realizado un estudio del acoplamiento y la integridad de la señal en configuraciones de PCB con tramos de tres pistas acopladas. Este estudio ha permitido identificar las transiciones y asimetrías en estos circuitos como posibles fuentes de interferencia y de degradación de las señales ya que la conversión modal se puede interpretar como a un proceso de interferencia que involucra todas las señales presentes. En el campo de las microondas, se ha realizado un análisis multimodal de filtros spurline. Este análisis ha permitido desarrollar dos nuevas estructuras, cuya principal característica es su compacidad que, a diferencia de otras estructuras similares, se consigue permitiendo la presencia de un nuevo modo en el proceso de resonancia. El uso de los modelos multimodales para el análisis de estas estructuras ha permitido una interpretación clara i sencilla del su funcionamiento así como el desarrollo de una serie de reglas de diseño que permiten un ajuste fácil i rápido de ciertos parámetros de los filtros como por ejemplo la frecuencia central y el ancho de banda.
A three-line-microstrip transmission line consists of three parallel coupled strips printed on a grounded dielectric substrate. The propagation in this line can be described in terms of three fundamental modes, namely the ee, oo and oe modes. These modes are orthogonal and propagate independently unless a transition or asymmetry is present in the line. Any transition or asymmetry will generate an energy exchange or modal interaction among all the propagating modes.
In this work, the modal interaction of a set of transitions and asymmetries in three-line-microstrip transmission lines is analyzed. The study is carried out by using the multimodal analysis. By means of this technique a set of multimodal circuit models (one for each transition) is derived. These models provide a simple and a quantitative interpretation of the modal interaction.
The proposed multimodal analysis is experimentally validated. The obtained results show that the derived multimodal models accurately predict the behavior of the transitions. Due to this fact, they can be used for the analysis of circuits and structures composed of three-coupled-strip sections. In this work, the models have been applied to both the EMC and microwave fields. In the former, they have been employed to study the cross-talk and signal-integrity problems in PCB configurations involving tree-coupled-trace sections. The performed analysis has shown that transitions and asymmetries in these circuits must be considered as a source of interference and signal degradation since the modal interaction can be interpreted as an interference process that involves all the present signals. In the latter, a multimodal analysis of spurline filters has been performed. This study has allowed the derivation of two new filter structures whose main feature is their compactness, which, in contrast to other analogous filters, is achieved by allowing the presence of an additional mode in the resonance process. The use of the multimodal models for the analysis of these structures has permitted both a simple interpretation of the filter operation and the derivation of a set of design rules which allows a rapid fine tuning of some filter parameters such as the center frequency and the bandwidth.
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Belhadj, Taher Aymen. "Etude théorique et expérimentale de composants innovants à fibres optiques multiples." Thesis, Limoges, 2016. http://www.theses.fr/2016LIMO0036/document.
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Les travaux de recherche présentés dans ce manuscrit ont pour but de concevoir, simuler, fabriquer et caractériser un convertisseur modal à base de canne microstructurée air-silice (CMAS). Cette fonction représente un élément clé pour les multiplexeurs modaux et les compensateurs de dispersion chromatique. Le composant proposé est basé sur une CMAS effilée dite « taper » qui constitue une transition entre les deux fibres différentes. La conversion se fait à travers l’excitation d’un mode particulier dans une fibre multimode à partir d’une fibre standard. Dans les structures à diamètre évolutif, la compréhension des différentes théories régissant le couplage entre les différents modes est nécessaire. Une étude approfondie est réalisée pour analyser le phénomène de couplage et étudier le critère d’adiabaticité. Ce composant est élaboré autour d’une technologie de fabrication existante à XLIM qui se base sur la technique fusion-étirage. Enfin, nous validons numériquement et expérimentalement ce principe. Nous réussissons à exciter le mode fondamental et d’autres modes d’ordre supérieur dans une fibre multimodeThese research works presented in this manuscript aim at designing, simulate, manufacture and characterizing the modal converter based microstructured air-silica cane. This function represents a key element for modal multiplexers and chromatic dispersion compensators. The proposed component is based on a tapered microstructured air-silica cane « taper » which constitutes a transition between the two different fibers. The conversion is done through the excitation of a particular mode in a multimode or few mode fibers from a standard fiber. In the tapered structures, the understanding of the different theories involving the coupling between the different modes was yet necessary. A thorough study is carried to analyze the phenomenon of coupling and study the adiabatic criterion. This component is developed around an existing manufacturing technology at XLIM which based in the technique « stack and draw». Finally, we validate numerically and experimentally that principle. We succeed to excite the fundamental mode and higher order modes in a multimode fiber
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Dougherty, Owen Robert. "The twelve steps of Alcoholics Anonymous as a model for moral conversion in American culture." Theological Research Exchange Network (TREN), 1996. http://www.tren.com.
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O'Heron, Patrick James 1966, and Patrick James 1966 O'Heron. "A multibody model simulating tilt-wing conversion." Thesis, The University of Arizona, 1991. http://hdl.handle.net/10150/291353.
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A multibody model is presented which simulates the conversion process associated with tilt-wing aircraft. A multibody dynamics approach is used to derive the equations of motion for a tilting articulated rotor with flap-pitch-lag root geometry. An enhanced model is used for the near-wake aerodynamics and uniform dynamic-inflow is used for the far-wake aerodynamics. A thrust control system computes the required trim settings. It is found that the controller can "fly" the model to a hover condition at a desired altitude, and can be used to achieve desired thrust levels during conversion. It is noted that conventional blade twist is inadequate during conversion. It is observed that unsteady aerodynamics are important during conversion. Also nonlinear effects on the tilt-wing cause large variations in tilt-torque during conversion.
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Clabby, Darragh. "Wave energy conversion at prototype and model scales." Thesis, Queen's University Belfast, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.673795.
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The performance of a Wave Energy Converter (WEC) may be estimated using both physical and numerical modelling techniques. Since numerical models are often informed by, and validated against data obtained from physical models, it is important to assess the accuracy with which a prototype's behaviour is predicted by its physical model. This thesis makes such an assessment for the case of a pitching flap type WEC, by comparing the performance of Aquamarine Power's Oyster1 prototype device to that of a representative physical model. This comparison was informed by considering the device in terms of three sub-systems, namely: the flap; the incident waves; and the power take-off (PTO) system. Understanding the effects of characteristics associated with each of these sub-systems on the device's behaviour was pursued using both physical and numerical modelling techniques. As well as informing the comparison between the device's performance at each scale, the conclusions drawn from this work, particularly in relation to the modelling of sea conditions and PTO systems, are relevant to WEC modelling in general. Agreement between the device's behaviour at each scale was assessed by comparing measurements of the flap's angular position and velocity, and the power captured by the PTO. The velocity measured at prototype scale was 12% greater than that measured at model scale. The disagreement between velocity measurements directly affected agreement between power capture measurements, which were also 12% greater at prototype scale compared to model scale. Damage to the PTO cylinders meant that the device's performance was sub-optimal. Extrapolation of the comparison between the device's performance at each scale suggested that the power captured was 7% greater at prototype scale relative to model scale at magnitudes of power capture more representative of optimal performance.
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Markham, Paul N. "Conversion converted : a new model of Christian conversion in light of Wesleyan theology and nonreductive physicalism." Thesis, Durham University, 2006. http://etheses.dur.ac.uk/1289/.
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The doctrine of conversion is central to Christian community life. There are a number of issues that influence how one conceives the phenomenon of conversion. Among these are one's view of spirituality, human nature, and basic notions of the 'self'. This thesis begins with the claim that contemporary views of Christian spirituality, particularly in the American Evangelical tradition, disproportionately emphasise the interior and individual nature of spiritual experience. This has a direct influence on doctrines of conversion in that their salient feature emerges as the redemption of an inner self or `salvation of the soul'. In order to promote a Christian community life that places discipleship at a premium, the author argues that a new model of conversion is needed within American Evangelicalism. Resources for such a model are found in the Wesleyan theological tradition as well as gathered from philosophical and scientific insights found in a nonreductive physicalist view of human nature. This thesis represents an integrated work in science and religion in that the author considers` data' from both theology and science. The author claims that Christian conversion is a process involving normal human biological capacities. It is characterised by a change in socio-moral attitude and behaviour, and is best understood as the acquisition of virtues intrinsic to Christian faith. Such acquisitions are facilitated through social interaction and participation in practices inherent to the Christian community. Furthermore, the conversion process should be viewed as the co-operant result of Divine grace and human participation.
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Cone, Steven Douglas. "Transforming Desire: The Relation of Religious Conversion and Moral Conversion in the Later Writings of Bernard Lonergan." Thesis, Boston College, 2009. http://hdl.handle.net/2345/1990.
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Thesis advisor: Frederick LawrenceThis work argues that religious conversion sublates moral conversion and also, de facto, serves as a necessary foundation for moral conversion. Religious conversion acts this way by transforming the religiously converted subject's feelings. Through this radical change in the subject's motivation, and the consequent change in the kinds of meanings that constitute the subject, religious conversion also transforms the nature of the human good of which the subject is a part. It thereby provides the basis for the right ordering of the human good toward transcendent value and a supernatural end
Thesis (PhD) — Boston College, 2009
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Theology
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Siddique, Zahed. "Conversion of CAD model data for virtual prototypes for disassembly." Thesis, Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/17877.
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Labasauskas, Vaidotas. "A theological analysis of Thomas Merton's conversion the moral dimension /." Theological Research Exchange Network (TREN), 2006. http://www.tren.com/search.cfm?p029-0686.
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Midha, Amit. "Conversion of 2-dimensional drawings into 3-dimensional solid model." Ohio : Ohio University, 1991. http://www.ohiolink.edu/etd/view.cgi?ohiou1183733016.
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Holland, Troy Michael. "A Comprehensive Coal Conversion Model Extended to Oxy-Coal Conditions." BYU ScholarsArchive, 2017. https://scholarsarchive.byu.edu/etd/6525.
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CFD simulations are valuable tools in evaluating and deploying oxy-fuel and other carbon capture technologies either as retrofit technologies or for new construction. However, accurate predictive simulations require physically realistic submodels with low computational requirements. In particular, comprehensive char oxidation and gasification models have been developed that describe multiple reaction and diffusion processes. This work extends a comprehensive char conversion code (the Carbon Conversion Kinetics or CCK model), which treats surface oxidation and gasification reactions as well as processes such as film diffusion, pore diffusion, ash encapsulation, and annealing. In this work, the CCK model was thoroughly investigated with a global sensitivity analysis. The sensitivity analysis highlighted several submodels in the CCK code, which were updated with more realistic physics or otherwise extended to function in oxy-coal conditions. Improved submodels include a greatly extended annealing model, the swelling model, the mode of burning parameter, and the kinetic model, as well as the addition of the Chemical Percolation Devolatilization (CPD) model. The resultant Carbon Conversion Kinetics for oxy-coal combustion (CCK/oxy) model predictions were compared to oxy-coal data, and further compared to parallel data sets obtained at near conventional conditions.
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Cummings, Jeremy P. "Spiritual Identity Formation: Testing a Model of Religious Conversion Processes." Bowling Green State University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1321191940.
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Johannesson, Elin. "A model for heterogenic catalytic conversion of carbon dioxide to methanol." Thesis, Linköpings universitet, Institutionen för fysik, kemi och biologi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-167498.
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Since our society became industrialised, the levels of carbon dioxide in our atmosphere have been steadily rising, to the point where it in early 2020 at is 413 ppm. The high concentration is causing several troubling effects worldwide because of the increase in mean temperature that it creates, which causes longer draughts, more severe floods, and rising seawater levels to name a few. There are a few measures that can be taken to reduce carbon dioxide in the atmosphere, among which there are a number of methods that currently are being researched and/or used. The prospect of capturing carbon dioxide and using it as a carbon building block to make methanol is one solution that is particularly interesting, since it in theory could provide a fuel for combustion engines that is net neutral regarding carbon emission. Methanol can be synthesised from carbon dioxide using a heterogeneous catalyst consisting of copper, Cu, and zinc oxide, ZnO. This research is focused on one of the components of the catalyst, the metal oxide ZnO in the form of crystallites or nanoparticles (ZnO)n. Quantum chemistry is a branch of computational chemistry which is centered on solving the Schrödinger equation for molecular systems. Density functional theory, DFT, is an approach to quantum theory which in this study was used to calculate the geometry and energy of the particles. The supercomputer Tetralith in the National Supercomputer Centre, NSC, was used to carry out the calculations. The DFT calculations utilized the functional B3LYP and the basis set 6-31G (d,p). One of the largest particle sizes studied, (ZnO)20, with a structure that has a large, flat surface, was found to be the most energetically favourable. According to studies, the presence of an oxygen vacancy on the surface of ZnO reduces the amount of activation energy required for CO2 to bond to the particle, which increases the chance of forming CO and thus continuing the process of forming methanol. Two structures of (ZnO)20 were investigated in this regard, where oxygen atoms were removed at different locations, creating four versions of Zn20O19 in total. This proved yet again that the version with a large, flat surface yields the lesser amount of energy when an O atom is removed from the centre of its surface. The adsorption of CO2 to the ZnO clusters was studied by calculating the energy of adsorption, and this showed that it was the second version of (ZnO)20, without an O vacancy, that yielded the least amount of energy, thus being the most favourable species to engage in physisorption with CO2. Lastly, the activation energy was investigated, and a diagram of the reaction process of CO2 adsorbing to Zn20O19 forming (ZnO)20 and CO is presented in this paper, which shows that the required activation energy is 127 kJ/mol.
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Ludwig, Wiebke. "Conversions of hydrocarbons with hydrogen over Pd model catalysts." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2011. http://dx.doi.org/10.18452/16258.
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Die Umsetzung von Kohlenwasserstoffen mit Wasserstoff auf Pd-Modellkatalysatoren wurde anhand von Molekularstrahlmethoden (MB) und IR-Spektroskopie mit Schwerpunkt auf dem Verständnis von mikroskopischen Faktoren, die die Aktivität und Selektivität bestimmen, studiert. Exemplarisch wurden die Reaktionen von cis-2-Buten mit H2(D2), cis-trans-Isomerisierung und Hydrierung, über einem geträgterten Pd/Fe3O4/Pt(1111)-Modellkatalysator und einem Pd(111)-Einkristall erforscht. Es wurde gezeigt, dass die Aktivität und Selektivität des Pd-Modellkatalysators stark von dessen Fähigkeit abhängt, ausreichend hohe Konzentrationen von H auf und in den Pd-Partikeln aufzubauen und aufrechtzuerhalten. Während Isomerisierung effektiv abläuft, wenn nur Oberflächen-H verfügbar ist, wird für die Hydrierung eine zweite Art von H-Spezies benötigt, welche mit Volumen-H assoziert ist. Kohlenstoffablagerungen auf niedrig-koordinierten Plätzen der Pd-Partikel induzieren anhaltende Hydrierung, was einer Begünstigung der H-Diffusion ins Pd-Volumen zugeschrieben wurde. Kohlenwasserstoffspezies hingegen inhibieren die Bildung von Oberflächen-H sowie noch stärker die von Volumen-H. Gepulste MB-Experimente zum H/D-Austausch zur Untersuchung der H-Verteilung zeigten, dass neben regulärem Oberflächen-H, eine zweite Art von H-Spezies, vermutlich Volumen-H, in die HD-Bildung involviert ist. C auf niedrig-koordinierten Plätzen beeinflusst die HD-Bildung vermutlich durch eine Erleichterung der H-Diffusion ins Pd-Volumen. Kohlenwasserstoffe hingegen inhibieren den H/D-Austausch. Die ersten Ergebnisse zur Adsorption und Reaktion von Isophoron, einem alpha,beta-ungesättigtem Keton, mit H2 auf einer Pd(111)-Oberfläche werden präsentiert. Veränderungen der Adsorptionsgeometrie wurden mit steigender Bedeckung und in Anwesenheit von H anhand von IRAS detektiert. In Übereinstimmung mit realistischen Katalysestudien wurde in TPR-Messungen eine deutliche Selektivität zur Hydrierung der C=C-Bindung festgestellt.The conversion of hydrocarbons with hydrogen over well-defined Pd model catalysts has been studied using pulsed molecular beam (MB) techniques and IR spectroscopy with a special focus on the understanding of microscopic factors governing the activity and selectivity. Exemplarily, the conversion of cis-2-butene with H2(D2) toward cis-trans isomerization and hydrogenation was studied over a supported Pd/Fe3O4/Pt(111) model catalyst and a Pd(111) single crystal surface. It was found that the activity and selectivity of the Pd model catalyst depend strongly on its ability to build up and maintain a sufficiently high concentration of H on and in the Pd particles. While isomerization proceeds effectively when merely surface H is available, for hydrogenation a second hydrogen species is required that is associated with subsurface hydrogen. Carbonaceous deposits located on low-coordinated sites of the Pd particles were found to induce persisting hydrogenation activity which could be attributed to facilitation of H diffusion to subsurface sites. Hydrocarbon species, in contrast, were found to inhibit the formation of surface H and even more pronounced subsurface H. Pulsed MB experiments on the H/D exchange to probe the H distribution showed that - next to regular surface H - a second type of hydrogen species is involved in the formation of HD, most likely subsurface hydrogen. C deposited on low-coordinated sites was shown to affect the HD formation presumably by facilitating subsurface H diffusion. Hydrocarbons strongly inhibit the H/D exchange. The first results on the adsorption and reaction of isophorone, an alpha,beta-unsaturated ketone, with hydrogen over a Pd(111) single crystal surface are presented. Changes in the adsorption geometry with increasing coverage and due to co-adsorbed H were detected using IRAS. In line with realistic catalytic studies, a strong chemoselectivity toward the hydrogenation of the C=C double bond was found in TPR measurements.
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Boyle, Joseph Edward. "Becoming Vegetarian: An Analysis of the Vegetarian Career Using an Integrated Model of Deviance." Diss., Virginia Tech, 2007. http://hdl.handle.net/10919/27476.
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This dissertation attempts to explore the nature of a particular food consumption pattern using a number of different deviance theories in order to outline the career path of vegetarianism. Using semi-structured interviews with 45 practicing vegetarians from two regions of the United States, the career path of the vegetarians was developed around David Matzaâ s (1969) theory of becoming deviant. Within each stage of Matzaâ s classic work, more specific theories were applied to explain the friction between vegetarianism and the more socially-accepted practice of meat eating within the United States. The framework of the stages includes the affinity for, affiliation with, and signification of vegetarian ideology and practice. Each stage within the theory is also a stage in the development of the vegetarian identity. The more specific theories utilized to explain phenomena within each particular stage attempt to show a progression from initially being interested in the ideals and practice of vegetarianism to becoming and verbalizing as a mature, practicing vegetarian. Finally, the vegetarians interviewed were asked to give the prognosis for the future of vegetarianism.Ph. D.
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Glass, Kevin Robert. "Automating the conversion of natural language fiction to multi-modal 3D animated virtual environments." Thesis, Rhodes University, 2009. http://hdl.handle.net/10962/d1006518.
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Popular fiction books describe rich visual environments that contain characters, objects, and behaviour. This research develops automated processes for converting text sourced from fiction books into animated virtual environments and multi-modal films. This involves the analysis of unrestricted natural language fiction to identify appropriate visual descriptions, and the interpretation of the identified descriptions for constructing animated 3D virtual environments. The goal of the text analysis stage is the creation of annotated fiction text, which identifies visual descriptions in a structured manner. A hierarchical rule-based learning system is created that induces patterns from example annotations provided by a human, and uses these for the creation of additional annotations. Patterns are expressed as tree structures that abstract the input text on different levels according to structural (token, sentence) and syntactic (parts-of-speech, syntactic function) categories. Patterns are generalized using pair-wise merging, where dissimilar sub-trees are replaced with wild-cards. The result is a small set of generalized patterns that are able to create correct annotations. A set of generalized patterns represents a model of an annotator's mental process regarding a particular annotation category. Annotated text is interpreted automatically for constructing detailed scene descriptions. This includes identifying which scenes to visualize, and identifying the contents and behaviour in each scene. Entity behaviour in a 3D virtual environment is formulated using time-based constraints that are automatically derived from annotations. Constraints are expressed as non-linear symbolic functions that restrict the trajectories of a pair of entities over a continuous interval of time. Solutions to these constraints specify precise behaviour. We create an innovative quantified constraint optimizer for locating sound solutions, which uses interval arithmetic for treating time and space as contiguous quantities. This optimization method uses a technique of constraint relaxation and tightening that allows solution approximations to be located where constraint systems are inconsistent (an ability not previously explored in interval-based quantified constraint solving). 3D virtual environments are populated by automatically selecting geometric models or procedural geometry-creation methods from a library. 3D models are animated according to trajectories derived from constraint solutions. The final animated film is sequenced using a range of modalities including animated 3D graphics, textual subtitles, audio narrations, and foleys. Hierarchical rule-based learning is evaluated over a range of annotation categories. Models are induced for different categories of annotation without modifying the core learning algorithms, and these models are shown to be applicable to different types of books. Models are induced automatically with accuracies ranging between 51.4% and 90.4%, depending on the category. We show that models are refined if further examples are provided, and this supports a boot-strapping process for training the learning mechanism. The task of interpreting annotated fiction text and populating 3D virtual environments is successfully automated using our described techniques. Detailed scene descriptions are created accurately, where between 83% and 96% of the automatically generated descriptions require no manual modification (depending on the type of description). The interval-based quantified constraint optimizer fully automates the behaviour specification process. Sample animated multi-modal 3D films are created using extracts from fiction books that are unrestricted in terms of complexity or subject matter (unlike existing text-to-graphics systems). These examples demonstrate that: behaviour is visualized that corresponds to the descriptions in the original text; appropriate geometry is selected (or created) for visualizing entities in each scene; sequences of scenes are created for a film-like presentation of the story; and that multiple modalities are combined to create a coherent multi-modal representation of the fiction text. This research demonstrates that visual descriptions in fiction text can be automatically identified, and that these descriptions can be converted into corresponding animated virtual environments. Unlike existing text-to-graphics systems, we describe techniques that function over unrestricted natural language text and perform the conversion process without the need for manually constructed repositories of world knowledge. This enables the rapid production of animated 3D virtual environments, allowing the human designer to focus on creative aspects.
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Uwaha, Makio. "The Classical Nucleation Model : Entire Process of Crystal Growth and Application to Chirality Conversion." AIP, 2010. http://hdl.handle.net/2237/20569.
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Bernadet, Sophie. "Conversion photocatalytique du CO2 sur monolithes poreux." Thesis, Bordeaux, 2018. http://www.theses.fr/2018BORD0172/document.
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Dans le contexte actuel de développement de nouvelles sources d'énergie non fossiles tout en minimisant l'impact environnemental, la production de carburants solaires par la valorisation des émissions anthropiques de CO2 apparaît comme une solution à fort potentiel. Le principal défi dans les processus artificiels photo-induits concerne le caractère bidimensionnel des systèmes utilisés, en raison de la faible profondeur de pénétration des photons. Ce travail de thèse se concentre sur le développement de mousses solides alvéolaires, issues de la chimie intégrative, présentant une porosité hiérarchiquement organisée. A travers l’imprégnation de précurseurs de TiO2, des photocatalyseurs autosupportés ont été synthétisés et ont montré une augmentation de la pénétration des photons d’un ordre de grandeur. D’autre part, ces solides limitent les réactions inverses par un effet de dilution, tout en assurant une sélectivité élevée envers la génération d'alcanes. Un modèle cinétique, basé sur un formalisme mixte de Langmuir-Hinshelwood et Eley-Rideal, est proposé pour décrire le comportement des matériauxIn the current context of developing novel non-fossil energy sources while minimizing the environmental impact, solar-driven-fuel-production by exploiting anthropogenic CO2 emissions appears to be a solution with great potential. The main challenge in artificial photo-induced processes concerns the two-dimensional character of the systems used, due to the low photon penetration depth. This thesis work focuses on the development of alveolar solid foams, derived from integrative chemistry and bearing a hierarchically organized porosity. By TiO2 precursor impregnation, self-standing photocatalysts were synthesized and provided a photon penetration increase by an order of magnitude. Moreover, these solids limit back-reactions by a dilution effect, while ensuring high selectivity towards alkane generations. A kinetic model, based on a mixed formalism of Langmuir-Hinshelwood and Eley-Rideal, is proposed to describe material behavior
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Acocella, Angela J. (Angela Josephine). "System model of small-scale gas-to-methanol conversion by engine reformers." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/98548.
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Thesis: S.M. in Technology and Policy, Massachusetts Institute of Technology, Engineering Systems Division, 2015.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (pages 88-93).
As global energy demands grow and environmental concerns over resource extraction methods intensify, high impact solutions are becoming increasingly essential. Venting and flaring of associated natural gas represents significant environmental and financial losses yet it continues in the North Dakota Bakken oil play. The valuable gas resource is wasted due to unfavorable economics and limited pipeline capacity. Similarly in India, underdeveloped gas transport infrastructure and restrictive regulatory frameworks prevent distribution and marketing of natural gas from the northeast regions, leaving it stranded in marginal fields. This thesis establishes a techno-economic model, utilizing Aspen Plus chemical processing software, and a discounted cash flow model to estimate economic feasibility of implementing MIT engine reformer-based gas-to-liquids (GTL) systems in the US or India. The system reforms natural gas via partial oxidation into synthesis gas (syngas) in the cylinders of an internal combustion engine, and can significantly reduce capital costs over conventional GTL reforming processes. The engine is operated in fuel rich conditions to generate the syngas, which is synthesized into methanol and dimethyl ether (DME). Once produced on-site, these liquids are more easily transported than gases. This study assesses the regulatory structures surrounding the upstream methane resource and downstream end product marketability for three scenarios: use of DME to replace existing local (1) diesel and (2) liquefied petroleum gas (LPG), or (3) sale of methanol as a commodity chemical on domestic or global markets. The analysis shows the system is economical in both locations. In the US, the minimum economically efficient production capacity with a 1-2 year payback period is 400,000- 860,000 standard cubic feet per day (scfpd) of natural gas for the range of end use scenarios considered. Differences in costs and product market characteristics in India result in a minimum efficient capacity of 330,000-810,000 scfpd of natural gas for the three scenarios.
by Angela J. Acocella.
S.M. in Technology and Policy
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Lahyaoui, Otmane. "Contribution to the study of magnetostrictive energy conversion : from material to device." Thesis, Compiègne, 2019. http://www.theses.fr/2019COMP2472.
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Dans cette ère du tout électrique, la demande en technologie électrique est en nette augmentation dans plusieurs secteurs (automobile, ferroviaire et aéronautique). Malheureusement, le bruit et les vibrations d’origine magnétiques provenant de ces technologies restent une problématique préoccupante dans ces moyens de transports, perturbant ainsi le confort des passagers. Sachant que le fonctionnement de ces dispositifs électriques comme les moteurs, les générateurs, les transformateurs repose en grande partie sur les matériaux ferromagnétiques, les principales sources d’émission acoustiques sont la magnétostriction et les forces magnétostatiques. Les travaux de thèse discutés dans ce manuscrit visent à améliorer les connaissances actuelles sur les propriétés magnétiques et magnétostrictives des matériaux ferromagnétiques (NO Fe-3%Si) dans une perspective de compréhension et de maitrise de leur comportement sous différentes sollicitations (contrainte mécanique, effet des fréquences d’excitation. . .). L’étude présentée offre une approche complète d’investigation partant du matériau jusqu’au dispositif électrique. Un premier volet expérimental présente les caractérisations magnétiques et magnéto-élastiques effectuées sur des tôles magnétiques et sur une structure stratifiée. S’ajoute à cela, une étude sur la résonance mécanique induite par la magnétostriction dans une structure stratifiée ressemblant à un transformateur.Un deuxième volet traite de la modélisation du comportement magnétoélastique de la magnétostriction et de son intégration dans un outil basé sur la méthode des éléments finis pour permettre de prédire la magnétostriction sur une structure plus complexe qu’une simple tôle. Enfin, une étude impliquant l’interaction de la magnétostriction avec les forces de magnétiques est décrite avec une comparaison des résultats de simulation avec une méthode analytique et avec des mesures expérimentalesIn this era of all-electric, the demand for electrical technology is clearly increasing in several sectors (automotive, rail and aeronautics). Unfortunately, magnetic noise and vibrations originating from these technologies remain a worrying issue in these means of transport, thus disrupting passenger comfort. Knowing that the operation of these electrical devices such as motors, generators and transformers relies largely on ferromagnetic materials, the main noise sources are magnetostriction and magnetic forces. The thesis works discussed in this manuscript aim to improve the current knowledge on the magnetic and magnetostrictive properties of ferromagnetic materials (NO Fe-3% Si) in a perspective of understanding and control of their behavior under different solicitations (mechanical stress, frequencies ...). The presented study offers a complete investigation approach from the material to the electrical device. A first experimental part presents the magnetic and magneto-elastic characterizations carried out on magnetic sheets and on a laminated structure. A study on the magnetic resonance induced by the magnetostriction including on an experimental modal analysis is presented as well. A second part deals with the modeling of the magneto-elastic behavior of magnetostriction and its integration into a finite element tool to predict the impact of the magnetostriction on a more complex structure than simple electrical sheet. Finally, a study of a possible interaction of magnetostriction with magnetic forcesis described with a comparison of simulation results with an analytical method and experimental measurements
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Alkiswani, Mutaz. "Spectrum conversion in solar cells industry : Novel model concept and steps towards commercialization." Thesis, Högskolan i Halmstad, Energivetenskap, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-28429.
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Solar photovoltaic industry is a hot research field, massive attempts are going on all over the world to increase its productivity in different ways. One of the challenges for solar cells is the light spectrum mismatch losses, which referred to the part of solar spectrum that cannot be utilized to electricity by the conventional cells. Two ways have been suggested to overcome solar spectrum mismatch losses, the first is multi layered cells (tandem cells) with a different light behavior for each layer, and the second is spectrum conversion which is this researches subject. Spectral modification or conversion in solar cells industry has been studied and different lab scale models have been introduced. According to nanoscale journal, such technology may be the base of the next generation solar cells, mentioning specifically the use of luminescence down conversion and up conversion techniques to control the light spectrum on the solar cell, these endeavors targets to produce solar cells that is not subjugated to Shockley-Queisser maximum efficiency limit of 31%. This research aims to draw a map of various ideas introduced to incorporate similar technologies in solar cell products, beside further suggestion to enhance its technical behavior and to push the commercialization of the technology forward. This is expected to reveal clear image about technology’s future development map for the upcoming studies, and to create a motivation for further studies towards a commercial production scale. The proposed commercialized model will result in enhancing the maximum theoretical efficiency limit to 48% if all spectral mismatch loses have been eliminated. Quantum energy level diagrams have been illustrated to describe each model’s performance under a theoretical light spectrum.
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Tang, Koon T. "Studies of '1'5'8Gd by thermal neutron capture reactions and by IBA-1 model calculations." Thesis, University of Brighton, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.361584.
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Lachance, Russell Philip. "A fundamental study of model fuel conversion reactions in sub and supercritical water." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/33701.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 2005.Includes bibliographical references.
Model reactants under hydrothermal conditions were examined to improve our understanding of chemical transformations in this high temperature and pressure environment. Results have a direct impact on present and future hydrothermal fuel conversion research for a range of fossil-based and bio-mass based feed stocks. Methane was chosen as a model compound and two different approaches were taken to examine its conversion in supercritical water. Catalytic reformation of methane was studied experimentally while partial oxidation of methane was studied through the application of a previously developed detailed chemical kinetic model that was analyzed and refined specifically for this study. Glucose and glycine were also chosen as model compounds to study related conversion pathways experimentally under hydrothermal conditions for biomass-based feed stocks. An experimental study of the catalytic reformation of methane in supercritical water (SCW) was completed that explored the use of carefully chosen catalysts under a variety of conditions and measured the conversion of methane and yields of various products.
(cont.) Eight metal catalysts were selected based on a review of previous catalysis experiments in hydrothermal conditions and those thought to be active for methane reforming. The range of conditions studied included 350 - 630⁰C, 150 - 400 bar, 0.01 - 2 wt% methane, 10 seconds to 72 minutes residence time, and with and without catalyst present. Four different experimental reactor designs were employed; a packed bed reactor, a continuous stirred tank reactor and two different batch reactor designs. A variety of techniques for reducing the metal catalysts and keeping them active in SCW were examined. Despite the range of conditions studied here, significant conversion of methane was never achieved. The most encouraging result was the relatively low yield of CO₂ (2.19% of the product gas volume) in the experiments employing 1% Ru/TiO₂ catalyst pellets. An analysis of each catalyst before and after exposure to SCW revealed significant degradation which helped to explain the low methane conversions. Based on this analysis and our experimental results, the most promising active metal identified was ruthenium, and the most promising support was titania (rutile) with some promise for zirconia and activated carbon.
(cont.) Although active for steam reforming and other hydrothermal catalyst applications, the nickel and platinum catalysts examined in this study showed signs of rapid degradation and deactivation and yielded little conversion of methane. In a previous study, researchers claimed to produce hydrogen from methane in SCW in the presence of alkali salts. Experiments with alkali salts in SCW were investigated here to further examine this claim. Our experiments with alkali salts revealed the importance of corrosion in the evolution of hydrogen from this media. Comparable amounts of hydrogen were produced from argon-alkali-SCW mixtures and from methane-argon-alkali-SCW mixtures suggesting that a significant amount of hydrogen in SCW reaction effluents can be attributed to water oxidizing the metal reactor material and not from hydrocarbon sources. Additional SCW alkali salt experiments in the same Hastelloy C-276 reactor eventually revealed an increasing catalytic conversion of methane, further emphasizing the likely importance of progressive metal corrosion.
(cont.) In the Hastelloy C-276 reactor, corrosion was confirmed by the presence of metal particulates and measurable amounts of dissolved nickel and chromium from the reactor metal alloy in the effluent. Comparable experiments in a gold-plated reactor still showed evidence of hydrogen generation from metal oxidation, but did not show evidence of corrosion. A detailed chemical kinetic model (DCKM) for single carbon species (C1) was refined and analyzed to support an examination of the effects of experimental conditions on methanol selectivity and methane conversion for the partial oxidation (POX) of methane in SCW. Although a formal sensitivity analysis was not performed on this model, a study of several key reactions and rates from literature resulted in good agreement of model predictions with reliable C1 SCW oxidation experimental data. SCW methane POX predictions from the refined model were then compared with POX experimental data. Disagreements between the model and the data were discussed along with a detailed critique of experimental issues associated with all previous SCW methane POX experimental studies.
(cont.) A reaction path analysis was developed from the DCKM which helped to elucidate the fate of methane and methanol in this environment and to identify a set of promising conditions to maximize methanol selectivity. Upon detailed analysis of both experimental and modeling results, the maximum methanol selectivity of about 80 % and maximum methane conversion of about 1% occurs at low temperatures ([approx.] 400⁰C), medium to high pressure (P > 300 bar), and high methane concentration ([CH₄]₀ > 50mM) with fuel-rich conditions at medium to high methane to oxygen ratios of [CH₄]₀/[0₂]₀ > 10. The experimental results may have achieved less than the maximum possible methanol selectivity due to issues such as inadequate mixing and wall effects. The modeling results may also be under-predicting methanol selectivity due to inadequate inclusion of non-ideal PVTN effects and solvent effects. However, the current model predictions and experimental results both substantiate our concern that SCW methane POX may fall short of the goal of greater than 70% methanol selectivity and 15% methane conversion. Nevertheless, other sets of experimental conditions that may show more promise have not been fully explored experimentally.
(cont.) In particular, the use of stable, selective catalysts, or inert wall material, or partial oxidation in the presence of hydrothermal flames have not been thoroughly analyzed here, and may improve the limited success discovered in this study. Glucose, glycine and glucose-glycine mixtures were studied as a model Maillard reaction system in a hydrothermal environment to explore a range of conditions that might alter the formation of undesired Maillard-type polymeric products. These polymeric products reduce the yield of biomass-derived fuels and complicate the separation and processing steps of biomass-to- fuel applications. Initial experiments were performed to study the individual hydrothermal degradation pathways of glycine and glucose and how those pathways change when the model compounds are mixed. Despite varying pH, time and temperature, we did not observe significant changes in the proposed Maillard mechanism, but product chromatograms did show possible development of alternate pathways particularly with furfural-type compounds.
(cont.) Glycine alone was found to be largely refractory (only 0 - 33% conversion) in our hydrothermal conditions from 50 to 300⁰C at 55 - 110 bar and 4 - 67 minutes residence time while glucose alone was quite reactive. In most conditions studied here, glucose conversion was greater than 85%, but moderate glucose conversions were achieved in a new, short residence time plug flow reactor (e.g., conversion of 35 % was measured after 7.3 seconds at 200⁰C and 55 bar). The degradation of glucose-glycine mixtures was studied at times of 7 seconds and 6 minutes at pH 2 and pH 5 and over a range of temperatures from 100 - 300⁰C. Near complete conversion of both reactants was observed in almost all conditions. Several liquid phase products were identified and analyzed, but total organic carbon (TOC) and carbon-hydrogen- nitrogen (CHN) analysis showed that significant reacted carbon is still unaccounted for.
by Russell P. Lachance.
Ph.D.
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Liu, S. "Plasma gas cleaning processes for the conversion of model tar from biomass gasification." Thesis, University of Liverpool, 2018. http://livrepository.liverpool.ac.uk/3021510/.
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Imamura, Hideo. "Minimal model for the secondary structures and conformational conversions in proteins." Thesis, University of Waterloo, 2005. http://hdl.handle.net/10012/1233.
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Better understanding of protein folding process can provide physical insights on the function of proteins and makes it possible to benefit from genetic information accumulated so far. Protein folding process normally takes place in less than seconds but even seconds are beyond reach of current computational power for simulations on a system of all-atom detail. Hence, to model and explore protein folding process it is crucial to construct a proper model that can adequately describe the physical process and mechanism for the relevant time scale. We discuss the reduced off-lattice model that can express α-helix and β-hairpin conformations defined solely by a given sequence in order to investigate a protein folding mechanism of conformations such as a β-hairpin and also to investigate conformational conversions in proteins. The first two chapters introduce and review essential concepts in protein folding modelling physical interaction in proteins, various simple models, and also review computational methods, in particular, the Metropolis Monte Carlo method, its dynamic interpretation and thermodynamic Monte Carlo algorithms. Chapter 3 describes the minimalist model that represents both α-helix and β-sheet conformations using simple potentials. The native conformation can be specified by the sequence without particular conformational biases to a reference state. In Chapter 4, the model is used to investigate the folding mechanism of β-hairpins exhaustively using the dynamic Monte Carlo and a thermodynamic Monte Carlo method an effcient combination of the multicanonical Monte Carlo and the weighted histogram analysis method. We show that the major folding pathways and folding rate depend on the location of a hydrophobic. The conformational conversions between α-helix and β-sheet conformations are examined in Chapter 5 and 6. First, the conformational conversion due to mutation in a non-hydrophobic system and then the conformational conversion due to mutation with a hydrophobic pair at a different position at various temperatures are examined.
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Yorgason, Robert Ivan. "Heteromorphic to Homeomorphic Shape Match Conversion Toward Fully Automated Mesh Morphing to Match Manufactured Geometry." BYU ScholarsArchive, 2016. https://scholarsarchive.byu.edu/etd/6414.
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The modern engineering design process includes computer software packages that require approximations to be made when representing geometries. These approximations lead to inherent discrepancies between the design geometry of a part or assembly and the corresponding manufactured geometry. Further approximations are made during the analysis portion of the design process. Manufacturing defects can also occur, which increase the discrepancies between the design and manufactured geometry. These approximations combined with manufacturing defects lead to discrepancies which, for high precision parts, such as jet engine compressor blades, can affect the modal analysis results. In order to account for the manufacturing defects during analysis, mesh morphing is used to morph a structural finite element analysis mesh to match the geometry of compressor blades with simulated manufacturing defects. The mesh morphing process is improved by providing a novel method to convert heteromorphic shape matching within Sculptor to homeomorphic shape matching. This novel method is automated using Java and the NX API. The heteromorphic to homeomorphic conversion method is determined to be valid due to its post-mesh morphing maximum deviations being on the same order as the post-mesh morphing maximum deviations of the ideal homeomorphic case. The usefulness of the automated heteromorphic to homeomorphic conversion method is demonstrated by simulating manufacturing defects on the pressure surface of a compressor blade model, morphing a structural finite element analysis mesh to match the geometry of compressor blades with simulated manufacturing defects, performing a modal analysis, and making observations on the effect of the simulated manufacturing defects on the modal characteristics of the compressor blade.
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Fabish, Michael K. "A simulation model of cargo handling for the MARS Class combat stores ship conversion." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1994. http://handle.dtic.mil/100.2/ADA294735.
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Albrecht, Tobias [Verfasser]. "Conversion of Lignocellulosic Materials and Model Compounds in Sub- and Supercritical Water / Tobias Albrecht." Aachen : Shaker, 2007. http://d-nb.info/1166512517/34.
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Kleinmann, Scott Matthew. "Jihadist radicalisation in the United States : testing a model of new religious movement conversion." Thesis, King's College London (University of London), 2018. https://kclpure.kcl.ac.uk/portal/en/theses/jihadist-radicalisation-in-the-united-states(bbdd0181-47dc-4aa5-b8cb-c775d30f0b52).html.
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There is no consensus regarding the causes of radicalisation. Some scholars argue that the failure to understand the phenomenon stems from poorly developed theoretical models. Given the shortcomings of radicalisation theories, a few scholars from the terrorism studies and social psychology of religion disciplines posit that religious conversion theories might be better suited than radicalisation models to explain why people join the jihadist movement. Specifically, these scholars hypothesise that the well-known New Religious Movement conversion theory—Lofland and Stark’s ‘World Saver’ model—might be applicable to radicalisation. This thesis tests asks the question: What causes radicalisation? More specifically, it asks: can the ‘World Saver’ model can account for radicalisation to jihadism? The study uses a two-phase mixed methods approach to answer this question. Phase-one is a qualitative, exploratory study which examines the backgrounds and experiences of six Al Qaeda-linked participants to determine if they are congruent with the model’s seven conditions. Phase-two builds on these exploratory findings with a quantitative study of 160 Muslims living in the US general population. Phase-two evaluates the participants’ scores on instruments that measure the conditions of the ‘World Saver’ model, their perceptions about the role of jihad in Islam, and their willingness to participate in illegal, violent political action and legal, non-violent political activism. This thesis also explores the overrepresentation of Muslim converts in jihadism by comparing convert and non-convert participants. The primary findings suggest that ‘World Saver’ is a valid model of behavioral radicalism, in that it predicts willingness to participate in illegal, violent political action. However, there is not a significant relationship between experiencing the model’s conditions and holding a militant interpretation of jihad. Therefore, Lofland and Stark’s model is not a valid model of cognitive radicalism. The analysis also finds that being a Muslim convert is not a significant predictor of behavioral or cognitive radicalism.
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Currin, Hugh D. "A dynamic prescribed vortex wake model for the FAST/AeroDyn wind energy conversions simulation code." abstract and full text PDF (free order & download UNR users only), 2007. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3258834.
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Baldow, Christoph, Lars Thielecke, and Ingmar Glauche. "Model Based Analysis of Clonal Developments Allows for Early Detection of Monoclonal Conversion and Leukemia." Public Library of Science, 2016. https://tud.qucosa.de/id/qucosa%3A30226.
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The availability of several methods to unambiguously mark individual cells has strongly fostered the understanding of clonal developments in hematopoiesis and other stem cell driven regenerative tissues. While cellular barcoding is the method of choice for experimental studies, patients that underwent gene therapy carry a unique insertional mark within the transplanted cells originating from the integration of the retroviral vector. Close monitoring of such patients allows accessing their clonal dynamics, however, the early detection of events that predict monoclonal conversion and potentially the onset of leukemia are beneficial for treatment. We developed a simple mathematical model of a self-stabilizing hematopoietic stem cell population to generate a wide range of possible clonal developments, reproducing typical, experimentally and clinically observed scenarios. We use the resulting model scenarios to suggest and test a set of statistical measures that should allow for an interpretation and classification of relevant clonal dynamics. Apart from the assessment of several established diversity indices we suggest a measure that quantifies the extension to which the increase in the size of one clone is attributed to the total loss in the size of all other clones. By evaluating the change in relative clone sizes between consecutive measurements, the suggested measure, referred to as maximum relative clonal expansion (mRCE), proves to be highly sensitive in the detection of rapidly expanding cell clones prior to their dominant manifestation. This predictive potential places the mRCE as a suitable means for the early recognition of leukemogenesis especially in gene therapy patients that are closely monitored. Our model based approach illustrates how simulation studies can actively support the design and evaluation of preclinical strategies for the analysis and risk evaluation of clonal developments.
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Baldow, Christoph, Lars Thielecke, and Ingmar Glauche. "Model Based Analysis of Clonal Developments Allows for Early Detection of Monoclonal Conversion and Leukemia." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-221771.
Full textAbstract:
The availability of several methods to unambiguously mark individual cells has strongly fostered the understanding of clonal developments in hematopoiesis and other stem cell driven regenerative tissues. While cellular barcoding is the method of choice for experimental studies, patients that underwent gene therapy carry a unique insertional mark within the transplanted cells originating from the integration of the retroviral vector. Close monitoring of such patients allows accessing their clonal dynamics, however, the early detection of events that predict monoclonal conversion and potentially the onset of leukemia are beneficial for treatment. We developed a simple mathematical model of a self-stabilizing hematopoietic stem cell population to generate a wide range of possible clonal developments, reproducing typical, experimentally and clinically observed scenarios. We use the resulting model scenarios to suggest and test a set of statistical measures that should allow for an interpretation and classification of relevant clonal dynamics. Apart from the assessment of several established diversity indices we suggest a measure that quantifies the extension to which the increase in the size of one clone is attributed to the total loss in the size of all other clones. By evaluating the change in relative clone sizes between consecutive measurements, the suggested measure, referred to as maximum relative clonal expansion (mRCE), proves to be highly sensitive in the detection of rapidly expanding cell clones prior to their dominant manifestation. This predictive potential places the mRCE as a suitable means for the early recognition of leukemogenesis especially in gene therapy patients that are closely monitored. Our model based approach illustrates how simulation studies can actively support the design and evaluation of preclinical strategies for the analysis and risk evaluation of clonal developments.
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Yue, Conghui. "Bridging the Gap in Biomass Conversion: Understanding Enzymatic Hydrolysis of Cellulose and Hydrogenative Degradation of Lignin at the Molecular Level." University of Cincinnati / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1627661055938336.
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Zhou, Chunguang. "Gasification and Pyrolysis Characterization and Heat Transfer Phenomena During Thermal Conversion of Municipal Solid Waste." Doctoral thesis, KTH, Energi- och ugnsteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-154587.
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The significant generation of municipal solid waste (MSW) has become a controversial global issue. Pyrolysis and gasification technologies for treating rejects from solid waste disposal sites (SWDSs), for which over 50 % of MSW is attributed to combustible species, have attracted considerable attention. MSW is an alternative energy source that can partly replace fossil resources; there is an increasing awareness that global warming caused by the utilization of fossil resources is occurring. The goal of this thesis is to realize the efficient and rational utilization of MSW and decrease the harmful impact of pollutants, such as dioxin, HCl, and CO2, on the environment. To achieve this goal, some fundamental studies have been experimentally and numerically conducted to enhance the understanding of the properties of municipal solid waste thermal conversion. In this thesis, the pyrolysis behaviors of single pelletized recovered fuel were tested. A detailed comparison of the pyrolysis behaviors of typical recovered solid waste and biomass particles was conducted. A swelling phenomenon with a swelling ratio of approximately 1.6 was observed on the surface of pelletized recovered fuels. Subsequently, a particle model was constructed to describe the thermal conversion process for large recovered fuel particles that are composed of a high fraction of polyethylene (PE) and a comparable low fraction of cardboard. The results indicate that an understanding of the heat transfer mechanism in highly porous and molten structures and the selection of a heat transfer model are crucial for accurate prediction of the conversion process. MSW pyrolysis is a promising method for producing liquid products. With the exception of lignocellulosic materials, such as printing paper and cardboard, PE, polystyrene (PS), polypropylene (PP), polyethylene terephthalate (PET), and polyvinyl chloride (PVC) are the six main polymers in domestic waste in Europe. Characterization studies of the products obtained from these individual components, such as PE, PET, PVC, printing paper, and cardboard, have been conducted on a pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) system and a fixed-bed reactor. The possible pathways for the formation of the main primary/secondary products in rapid and conventional pyrolysis were also discussed. MSW steam gasification with CaO was performed in a batch-type fixed-bed gasifier to examine the effect of CaO addition on the heat transfer properties, pollutant removal, and devolatilization and char gasification behaviors in the presence of steam. A new carbon capture and recycle (CCR) system combined with an integrated municipal solid waste system was proposed. The foundation of the system is the development of a novel method to remediate CO2 using a high-temperature process of reforming CH4 and/or O2 and/or H2O without catalysts. Thermodynamic and experimental studies were performed. High temperatures significantly promoted the multi-reforming process while preventing the problem of catalyst deactivation. Potential improvements in the efficiency of the novel technology can be achieved by optimizing the reforming reactants. Landfill gas (LFG) and fuel gas from bio-waste treatment contain a considerable fraction of CH4, which may be a source of CH4 for this process.QC20141028
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Hartt, Samuel T. "A biblical critique of the Haitian peasant's mindset on moral responsibility as it relates to the conversion experience." Theological Research Exchange Network (TREN), 1986. http://www.tren.com.
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Xiao, Yaowu Braiman Mark S. "Role of conserved arginine in solar energy conversion infrared spectroscopy of bacteriorhodopsin, proteorhodopsin, and model compounds /." Related electronic resource: Current Research at SU : database of SU dissertations, recent titles available full text, 2004. http://wwwlib.umi.com/cr/syr/main.
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Gamble, Stephen R. "Reversible solid oxide fuel cells as energy conversion and storage devices." Thesis, University of St Andrews, 2011. http://hdl.handle.net/10023/2454.
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A reversible solid oxide fuel cell (RSOFC) system could buffer intermittent electrical generation, e.g. wind, wave power by storing electrical energy as hydrogen and heat. RSOFC were fabricated by thermoplastic extrusion of (La₀.₈Sr₀.₂)₀.₉₅MnO[subscript(3−δ)] (LSM) ceramic support tubes, which were microstructurally stable with 55% porosity at 1350°C. A composite oxygen electrode of LSM-YSZ was applied, providing a homogeneous substrate for a 20 μm - 30 μm thick YSZ electrolyte. A dip-coated 8YSZ slurry, and a painted commercial 3YSZ ink gave sintered densities of 90% and nearly 100% at 1350°C, respectively. A porous NiO/YSZ fuel electrode was also painted on. A Ag/Cu reactive air braze was unsuccessful at forming a void-free joint between the RSOFC and a 316 stainless steel gas delivery tube, as the braze did not penetrate the oxidation layer on the steel. Two alumina-based ceramic cements failed to fully seal the cell to an alumina gas delivery tube, due to thermal expansion coefficient mismatches and porosity after curing. Therefore, the maximum open circuit voltage (OCV) obtained during RSOFC testing was 0.8 V at 440°C. LSM-YSZ symmetrical cell performance measurements with oxygen pressure showed a diffusion polarisation, which was assigned to dissociative adsorption and surface diffusion of oxygen species. A collaborative RSOFC system software model showed ohmic and activation losses dominated the RSOFC, and diffusion losses were insignificant. Pressurisation from 1 to 70 bar increased the RSOFC Nernst voltage by 11% at 900°C, and reduced the entropy of the gases, reducing heat production and increasing electrical efficiency. A 500 kg Sn/Cu phase change heat store prevented the system overheating. Over a 16 h discharge-charge RSOFC cycle in the range 5 mol.% - 95 mol.% hydrogen in steam, at 20.4 A per cell or 3250 A m⁻², the electrical energy storage efficiency was 64.4%.
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McKeon, Peter. "A fundamental study to enable ultrasonic structural health monitoring of a thick-walled composite over-wrapped pressure vessel." Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/54308.
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A structural health monitoring system is desired to monitor the integrity of cylindrical, multi-layer carbon over-wrapped pressure vessels intended to house hydrogen at high pressures. In order to develop the system based on ultrasonic guided wave technology, the interaction between ultrasonic guided waves and defect types of interest must be understood. Finite element models in two and three dimensions are developed to predict guided wave motion in the reservoirs. Key parameters are optimized including frequency range, excited modes, detected modes, and transducer dimensions. A novel baseline subtraction technique in the frequency wavenumber domain is presented to increase lower level detection limits. Some experiments are carried out to corroborate the findings in the finite element environment.
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Tymoczko, Jakub [Verfasser], Wolfgang [Akademischer Betreuer] Schuhmann, and Aliaksandr S. [Akademischer Betreuer] Banarenka. "Engineering of model electrocatalysts for energy conversion and storage / Jakub Tymoczko. Gutachter: Wolfgang Schuhmann ; Aliaksandr S. Banarenka." Bochum : Ruhr-Universität Bochum, 2016. http://d-nb.info/1089007272/34.
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Naswa, Sudhir. "Representation of Biochemical Pathway Models : Issues relating conversion of model representation from SBML to a commercial tool." Thesis, University of Skövde, School of Humanities and Informatics, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-28.
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Background: Computational simulation of complex biological networks lies at the heart of systems biology since it can confirm the conclusions drawn by experimental studies of biological networks and guide researchers to produce fresh hypotheses for further experimental validation. Since this iterative process helps in development of more realistic system models a variety of computational tools have been developed. In the absence of a common format for representation of models these tools were developed in different formats. As a result these tools became unable to exchange models amongst them, leading to development of SBML, a standard exchange format for computational models of biochemical networks. Here the formats of SBML and one of the commercial tools of systems biology are being compared to study the issues which may arise during conversion between their respective formats. A tool StoP has been developed to convert the format of SBML to the format of the selected tool.
Results: The basic format of SBML representation which is in the form of listings of various elements of a biochemical reaction system differs from the representation of the selected tool which is location oriented. In spite of this difference the various components of biochemical pathways including multiple compartments, global parameters, reactants, products, modifiers, reactions, kinetic formulas and reaction parameters could be converted from the SBML representation to the representation of the selected tool. The MathML representation of the kinetic formula in an SBML model can be converted to the string format of the selected tool. Some features of the SBML are not present in the selected tool. Similarly, the ability of the selected tool to declare parameters for locations, which are global to those locations and their children, is not present in the SBML.
Conclusions: Differences in representations of pathway models may include differences in terminologies, basic architecture, differences in capabilities of software’s, and adoption of different standards for similar things. But the overall similarity of domain of pathway models enables us to interconvert these representations. The selected tool should develop support for unit definitions, events and rules. Development of facility for parameter declaration at compartment level by SBML and facility for function declaration by the selected tool is recommended.
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Horlamus, Felix [Verfasser], and Rudolf [Akademischer Betreuer] Hausmann. "Biotechnological conversion of lignocellulose hydrolyzates : model microorganisms for a bio-based economy / Felix Horlamus ; Betreuer: Rudolf Hausmann." Hohenheim : Kommunikations-, Informations- und Medienzentrum der Universität Hohenheim, 2020. http://d-nb.info/1219574120/34.
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Dhen, Mikaël. "Muon to electron conversion, flavored leptogenesis and asymmetric dark matter in minimal extensions of the Standard Model." Doctoral thesis, Universite Libre de Bruxelles, 2015. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/217745.
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Il est clair que le Modèle Standard des particules élémentaires n'est pas complet. Parmi tous les indices d'une physique au-delà du Modèle Standard, la masse des neutrinos, l'asymétrie matière-antimatière de notre Univers et la matière noire constituent les trois contextes généraux de cette thèse.Le fait que les neutrinos soient massifs constitue la plus claire évidence d'une physique au-delà du Modèle Standard. La masse des neutrinos peut trouver une explication notamment dans le cadre des modèles favoris dits "modèles Seesaw". Ces modèles, en plus de générer une petite masse pour les neutrinos, génèrent aussi des processus dans lesquels la saveur d'un lepton chargé est changée, comme la désintégration d'un muon en un électron et un photon, ou la conversion d'un muon en un électron au sein d'un atome sans émission de neutrino. Ces processus sont importants car les expériences futures devraient atteindre des sensibilités impressionnantes sur leurs taux, mais aussi parce que leur observation confirmerait l'existence d'une physique nouvelle et pourrait peut-être discriminé parmi les différents modèles. Il est donc important d'avoir une expression analytique fiable du taux de ces processus dans le cadre de ces modèles Seesaw favoris. Dans la première partie de cette thèse, nous calculons l'expression du taux de conversion d'un muon en un électron au sein d'un atome dans le cadre des modèles Seesaw de type 1, et analysons la phénoménologie s'y rapportant. Ces modèles Seesaw, en plus de générer une petite masse pour les neutrinos et des processus changeant la saveur leptonique, permettent aussi la création de l'asymétrie matière-antimatière dans l'Univers, à travers le mécanisme dit de "leptogenèse". Selon ce mécanisme, une asymétrie leptonique aurait d'abord été créée, avant d'être partiellement transférée en une asymétrie baryonique. Dans la seconde partie de cette thèse, nous calculons et analysons la leptogenèse dans le cadre des modèles Seesaw de type 2 avec, pour la première fois, la prise en compte des effets de saveurs.Finalement, la troisième et dernière partie de cette thèse se concentre sur la possibilité de générer non seulement la matière baryonique à partir d'une asymétrie, mais aussi la matière noire. A cette fin, nous considérons le modèle dit "doublet inerte'', car il contient une interaction qui pourrait à priori générer de la matière noire à partir d'une asymétrie. Nous adressons dès lors la question suivante et y répondons: est-il possible de générer toute la matière noire à partir d'une asymétrie de matière noire dans le contexte du modèle doublet inerte ?Option Physique du Doctorat en Sciences
info:eu-repo/semantics/nonPublished
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Safi, Farah. "Le prosélytisme intellectuel et le droit pénal." Thesis, Paris 2, 2012. http://www.theses.fr/2012PA020036.
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Le droit pénal ne contient, certes, aucune infraction de prosélytisme intellectuel nommée comme telle, mais il connaît, depuis longtemps, la conversion idéologique et s’y intéresse par le moyen de plusieurs types d’incriminations. En effet, s’il demeure, au nom du respect des libertés fondamentales, complètement indifférent à l’appropriation d’une idéologie par le prosélyte, il intervient à chaque fois que l’expression de celle-ci porte atteinte aux valeurs sociales qu’il protège. C’est notamment le cas lorsqu’une idéologie agressive est diffusée : elle échappe à tout contrôle possible par le prosélyte, si bien que sa propagation est source de trouble pour l’ordre public et justifie ainsi sa répression par une infraction d’idéologie. En outre, le droit pénal s’intéresse au comportement du prosélyte : lorsque l’acte qu’il réalise en vue de convertir autrui à une idéologie heurte les valeurs protégées par le législateur pénal, des infractions par idéologie existent pour limiter le prosélytisme intellectuel. Elles ont vocation à réprimer non pas la conversion idéologique en tant que telle, mais les moyens utilisés par le prosélyte au cours du processus de conversion et qui constituent, eux, une menace pour l’ordre et la sécurité publics. Par conséquent, que ce soit à travers des infractions d’idéologie ou par idéologie, le droit pénal contient déjà la réponse pour combattre le prosélytisme intellectuel qui risque de menacer la tranquillité sociale. Dès lors, en dépit de la tendance actuelle qui privilégie le recours à l’arme répressive pour combattre le terrorisme, les sectes dites dangereuses et l’homme criminel – dangereux, à son tour –, aucune intervention législative qui irait dans le sens de la création d’une nouvelle incrimination de prosélytisme intellectuel n’est la bienvenue. En revanche, l’étude du prosélytisme intellectuel a permis de mettre en évidence une particularité propre au délinquant prosélyte qui devrait être prise en compte aussi bien par le législateur que par le juge pénal : animé par une idéologie, le prosélyte devrait être toujours traité comme un délinquant politique et les infractions de prosélytisme intellectuel innommées devraient alors, elles aussi, recevoir cette qualificationCriminal law does not explicitly incorporate criminal offenses directly related to intellectual proselytism per se. Nevertheless, references to ideological conversion have long been cited in several types of criminal offenses. Criminal law holds that each person has the fundamental human right of freedom of thought, conscience, and religion, and does not interfere in the act of a proselyte adopting an ideology. However, the law is implicated whenever an ideology is conveyed in such a manner that threatens the social values the law is bound to protect. For instance, an aggressive ideology is a real danger to the public order, and can spread and spin out of control. In such cases, it is justified and necessary to consider ideological conversion as a crime named ideological offense.Furthermore, the behavior of the proselyte is of concern, whenever an action to convert a person to an ideology is in conflict with the values that criminal legislators are protecting. Specific offenses induced by an ideology are in place to impede intellectual proselytism. These types of offenses aim to penalize the methods used by the proselyte during conversion, rather than prohibit the ideological conversion itself, as the methods themselves constitute a danger to the public order and safety.Consequently, criminal law already encompasses offenses based on ideological ground or induced by ideology, and which constrain intellectual proselytism that is at risk of disturbing the social order. Any new draft law and intervention to propose additional incrimination related to intellectual proselytism are questionable, in spite of the recent tendency to eradicate terrorism, dangerous sects, or criminals by means of repressive weapons.Interestingly, the study completed on intellectual proselytism has shown that there exist particularities of an intellectual proselyte which are analogous to a political delinquent. And this fact must be taken into account by both prosecutors and criminal judges. A proselyte who is supporting a strong ideology is similar to a political delinquent and thereby, offenses related to intellectual proselytism should be treated in the same manner as infractions of a political delinquent
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Barbier, Jérémie Alain. "Relation structure/réactivité en conversion hydrothermale des macromolécules de lignocellulose." Thesis, Bordeaux 1, 2010. http://www.theses.fr/2010BOR14144/document.
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Ce travail porte sur l'étude des voies réactionnelles accompagnant la liquéfaction desconstituants de la biomasse lignocellulosique dans un milieu aqueux proche du pointcritique. La stratégie expérimentale consiste à étudier la réaction en unité pilote decomposés lignocellulosiques modèles et à développer une approche analytiquemultitechnique originale afin de caractériser les structures et les masses moléculairesdes produits. Les résultats obtenus montrent que les schémas réactionnels sontcomplexes faisant intervenir de nombreuses voies de fragmentation et de condensationcompétitives. L'étude cinétique à différents temps de séjour montre que la fractionglucidique de la biomasse lignocellulosique a une réactivité très différente de sa fractionligneuseThis work deals with the study of the reaction pathway during the lignocellulosicconstituent liquefaction by water near its critical point. Experimental method consists ininvestigation of lignocellulosic model compounds conversion in pilot plant combined withdevelopment of a new multitechnique analytical approach in order to characterizeproduct chemical structures and molecular weights. Results show that reaction pathwaysare very complex consisting to several fragmentation and condensation competitivereactions. The kinetic study with different reaction times reveals an important differenceof comportment for the glucidic fraction than the lignin fraction of biomass
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Wilkie-Chancellier, Nicolas. "Réflexion et conversion d'une onde de Lamb à l'extrémité biseautée d'une plaque." Phd thesis, Université du Havre, 2003. http://tel.archives-ouvertes.fr/tel-00006282.
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Ce travail est consacré à l'étude de l'interaction d'ondes de Lamb avec un biseau. L'objectif est d'identifier les différents modes propagatifs issus de la conversion de l'onde incidente sur l'extrémité biseautée d'une plaque et d'évaluer l'énergie transportée par chaque mode. Dans un premier temps, cette étude est réalisée expérimentalement sur une plaque d'acier inoxydable. Les bilans d'énergie sont déduits des mesures des déplacements en surface par interférométrie laser. Ils sont corrigés pour tenir compte de la diffraction des ondes ultrasonores. Un modèle théorique, basé sur une décomposition modale, est ensuite mis en œuvre afin de justifier les résultats précédents. Le calcul des coefficients de réflexion en énergie a été mené dans le cas des modes de Lamb A0, S0 et A1 incidents sur des extrémités biseautées de 65 à 90° pour un produit fréquence-épaisseur FE variant de 1 à 4 MHz.mm. Les bilans quantitatifs obtenus par cette méthode valident les résultats expérimentaux. Le calcul théorique met en évidence l'importance des « modes complexes » existant dans la plaque. Une simulation par éléments finis a montré leur influence sur les réflexions et a permis d'évaluer à quelle distance du biseau les modes de Lamb se propagent seuls. Enfin, une étude est effectuée pour décrire l'influence d'un biseau sur le comportement du « mode de bout », phénomène particulier pouvant se produire à l'extrémité d'une plaque dans une gamme fréquentielle étroite lorsque le mode de Lamb S0 est incident.
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Zhang, Bin. "Model for coupled ferroelectric hysteresis using time fractional operators : Application to innovative energy harvesting." Thesis, Lyon, INSA, 2014. http://www.theses.fr/2014ISAL0065/document.
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Les systèmes de récupération d’énergies basées sur les vibrations mécaniques environnantes suscitent l’intérêt depuis de nombreuses années. Augmenter l’efficacité de la conversion d'énergie est primordial, mais celle-ci pour être bien maitrisée, passe par la mise au point de modèles précis et notamment par la prise en compte des lois régissant les matériaux piézoélectriques. En effet, ces matériaux sont à la base des couplages mécano/électriques et il est capital de comprendre comment ils fonctionnent quelque soit l'excitation externe. Un modèle précis du matériau ferroélectrique est indispensable pour établir des critères de conception des prototypes et leur optimisation. Dans cette thèse, un modèle précis, temporel, large bande tenant compte de l’ensemble des non-linéarités d’une céramique piézoélectrique a été développé. L’utilisation d’opérateurs fractionnaires a permis d’augmenter fortement la bande de fréquence de validité du modèle. Le modèle permet notamment de prévoir l’évolution de la polarisation diélectrique ainsi que le déplacement mécanique de l’échantillon testé et ceci quelque soit le type de stimulation (contrainte mécanique pure, champ électrique et même excitation hybride électriques/mécaniques). La dérivé fractionnaire a dans un premier temps été utilisée pour l’hystérésis sous excitation électrique pour décrire le comportement dynamique de la polarisation diélectrique. En effet, au delà d’un seuil de fréquence, lorsque l’état du matériau n’est plus quasi-statique, une contribution dynamique apparaît. Cette contribution joue un rôle primordial lorsque les niveaux de fréquence et d’amplitude sont élevés. La même étude a ensuite été menée sous contrainte mécanique, et le même opérateur fractionnaire a été utilisé avec succès. Nous avons entre autre constaté que sur un même échantillon les paramètres de simulation établis sous champ électrique étaient conservés sous contrainte mécanique. Ensuite, un modèle inverse permettant d’imposer la forme d’onde de la polarisation ou du déplacement a été proposé. Pour une polarisation ou un déplacement donné, le modèle inverse permet de déterminer avec précision l’effort mécanique à appliquer sur la céramique piézo-électrique. Ces modèles sont nécessaires pour optimiser une forme d’onde de contrainte mécanique ou électrique et obtenir un rendement supérieur des systèmes récupérateurs d’énergie. En effet, une nouvelle technique couplée champ électrique/contrainte mécanique de récupération d’énergie est présentée à la fin de la thèse, technique qui nous a permis de valider l’utilisation du modèle. L’utilisation du modèle permet d’optimiser la mise au point d’un prototype mais également d’obtenir la valeur exacte du rendement de la méthode en rendant compte notamment des pertes diélectriques. Dans la thèse, le modèle sous ses différentes variantes est décrit de manière exhaustiveEnergy harvesting based on mechanical vibration has been a long time research topic for the last few decades. In addition to enhancing the energy conversion amount, another objective is to master and give a precise model with consideration of the disciplines of piezoelectric material behavior. A precise model for the ferroelectric material is mighty needed in the energy harvesting process, so as to give an instruction to the prototype designing and modelling optimizing. In this thesis, a model working on wide bandwidth considering the nonlinearity of the piezoceramic has been developed. The employment of the fractional derivative has broadened the usage of this model on expanded bandwidth. The model permit to predict the evolution of the dielectric polarization as well as the mechanical displacement, which has been tested on different samples under different kinds of stimulation (pure mechanical, pure electrical and hybrid of electrical and mechanical excitations). This fractional derivative factor has been first developed under electrical excitations to describe the dynamic behavior. In the development of this model to mechanical field, the fractional derivative factor was found available as well under the mechanical excitation in the same value. In the following study, an inverse of mechanical model has been developed as well. In the end, we stimulate the piezoceramic using both electrical and mechanical excitation to augment the energy harvesting amount which could become a promising method in energy harvesting field. Every model has been exhaustively demonstrated and specific measuring benches have been established to validate these models. Experiments results and simulations in different kinds of excitations (amplitudes, frequencies) for every kind of the above models have been compared. Good approximation has been acquired indicating the model has a good accuracy in describing the material property and dynamic behavior
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Nguyen, Betty Ngoc Thy 1982. "Catalytic partial oxidation of methyl acetate as a model to investigate the conversion of methyl esters to hydrogen." Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=99783.
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Rhodium, platinum, copper, palladium, and rhodium-ceria catalysts were investigated in the catalytic partial oxidation of methyl acetate, the simplest methyl ester, to better understand the conversion of biodiesel to hydrogen. Only rhodium and rhodium-ceria catalysts allowed for an autothermal reactor operation. Both catalysts were active in producing hydrogen, carbon monoxide, water, and carbon dioxide, although the rhodium-ceria catalyst showed the greater methyl acetate conversion and the greater hydrogen and carbon monoxide selectivities. A low C/O feed ratio favored the methyl acetate conversion, the hydrogen selectivity, and the carbon monoxide selectivity. Furthermore, a high gas hourly space velocity also improved the reactor performance. According to the experimental data, it appears that the oxidation of methyl acetate forms carbon monoxide and water as a primary step, instead of carbon dioxide and water as with the combustion reaction. In general, methyl acetate does not yield more synthesis gas than biodiesel. The methyl ester functional group limits the hydrogen yield and hence new catalysts should be developed and investigated in order to better target the decomposition of methyl esters to hydrogen.
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Silva, Junior Antonio Carlos da Rosa. "Recuperação religiosa de presos: conversão moral e pluralismo religioso na APAC." Universidade Federal de Juiz de Fora, 2013. https://repositorio.ufjf.br/jspui/handle/ufjf/1213.
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A presente dissertação analisa a religiosidade no método APAC e a aloca como um dos mecanismos utilizados na recuperação dos presos. Para tanto, investigamos, de início, como os Cursilhos de Cristandade, em seu ramo que se opõe à Teologia da Libertação, berço dos primórdios apaqueanos, influenciaram na perspectiva religiosa apregoada pela instituição até os dias de hoje. Após, apresentamos um breve histórico do discurso da APAC, enfatizando a sistematização do método nos escritos mais recentes de seu fundador, Mário Ottoboni. Balizado esse viés discursivo (primeira parte), passamos a discorrer sobre os resultados da nossa pesquisa de campo acerca de dois eixos basilares, que nos permitiram uma melhor compreensão do nosso objeto. Trata-se, de plano, da noção de conversão moralizante – a conversão pessoal do preso dá azo às suas mudanças de comportamento –, bem como da verificação de como o quadro de afloramento da religiosidade dinamiza o pluralismo religioso na APAC.
This dissertation analyzes the religiosity in method APAC and allocates as one of the mechanismis utilized in the recovery of prisoners. For this, we investigated, initially, as the Cursillo of Christianity, in their field that opposes to Liberation Theology, origin of the early of APAC, influence in religious perspective proclaimed to institution until the present day. After, we show a concise history of the discourse of APAC, emphasizing the sistematization of the method in more recent writings of its founder, Mário Ottoboni. Delimited this bias discursive (first part), we discuss the results of our field research on two basics axles, which allowed us a better understanding of our object. This refers, in the plan, of the notion of moralizing conversion – the prisioner’s personal conversion gives rise to their behavior changes – as well as the verification of how the frame of outcrop of the religiosity dinamizes the religious pluralism in APAC.
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Brandt, Bjoern. "Selectivity in hydrocarbon conversions and methanol decomposition on a Pd/Fe 3 O 4 model catalyst." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2008. http://dx.doi.org/10.18452/15854.
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Selektivität zu erreichen ist eines der Hauptziele der Chemie. In der Katalyse wird allgemein von einem engen Zusammenhang zwischen der Selektivität und der Katalysatorstruktur ausgegangen - allerdings erschwert die komplexe mikroskopische Struktur realer Katalysatoren ein tiefergehendes Verständnis; daher wird versucht, weitergehende Erkenntnisse an strukturell vereinfachten Materialien zu gewinnen. Für diese Arbeit wurde hierzu ein Pd/Fe3O4-Modellkatalysator verwendet. Auf diesem System wurde die Selektivität in zwei katalytische Modellreaktionen untersucht. Die Reaktantenexposition erfolgte dabei über Molekularstrahlen im Hochvakuum, und die Reaktionsraten wurden massenspektrometrisch gemessen; Adsorbate wurden IR-spektroskopisch detektiert. - Zersetzung von Methanol: Es wird gezeigt, dass Methanol auf dem Oxid Fe3O4 sehr selektiv durch Reaktion mit Oberflächensauerstoff (Mars-van-Krevelen-Mechanismus) zu Formaldehyd und Wasser dehydrogeniert wird. Auf Pd-Metall zersetzt sich Methanol im wesentlichen sehr schnell zu Kohlenstoffmonoxid und Wasserstoff (bzw. zu Kohlenstoffablagerungen in einer Nebenreaktion). Es werden Experimente gezeigt, die darauf hindeuten, dass Diffusion von oxidgebundenem Methanol/Methoxy auf die Pd-Metallpartikel signifikant zur Gesamtaktivität des Modellkatalysators beiträgt. - Umsetzung von 2-Buten mit Deuterium: Zunächst wird gezeigt, dass die Erzielung katalytischer Aktivität kritisch von der dissoziativen Adsorption des Reaktanden Deuterium abhängt, die durch Kohlenwasserstoffadsorbate stark inhibiert wird; es war allerdings möglich, diese Limitierung experimentell zu umgehen. Darüberhinaus wird gezeigt, dass die Hydrierungsreaktion durch die Anwesenheit stark zersetzter Kohlenwasserstoffablagerungen selektiv induziert werden kann, während die alternative Reaktion (H/D-Austausch/Isomerisierung) auch in Abwesenheit dieser Spezies abläuft; mögliche Erklärungsmodelle werden diskutiert. Schließlich wird die mögliche Ursache für die unter bestimmten Reaktionsbedingungen beobachteten unterschiedlichen Reaktionsraten mit cis- und trans-2-Buten als Reaktanten diskutiert.The achievement of selectivity is one of the main objectives in chemistry. For catalysis, selectivity is generally seen to be closely linked with catalyst structure; the complex microscopic structure of real catalysts, however, obstructs to obtain a deeper understanding; for this reason, structurally simplified materials are studied. For the current work, studies have been conducted on a Pd/Fe3O4 model catayst. On this system, the selectivity in two catalytic reactions has been examined. The exposure of the reactants was effected by molecular beams in high vacuum, and the reaction rates have been measured mass spectrometrically; additionally, adsorbates were detected by IR-spectroscopy. - Decomposition of Methanol: It is shown that on the oxide Fe3O4 methanol is dehydrogenated very selectively to formaldehyde and water by reaction with surface oxygen of the oxide (Mars-van-Krevelen mechanism). On Pd metal it is mainly decomposed very quickly to carbon monoxide and hydrogen (and, in a side reaction, to carbonaceous deposits). Experiments are shown indicating that the diffusion of oxide-related methanol and methoxy to the Pd metal-particles contributes significantly to the overall activity of the model catalyst. - Conversion of 2-Butene with Deuterium: At first it is shown that the catalytic activity depends critically on the dissociative adsorption of the reactant deuterium, which is strongly inhibited by hydrocarbon adsorbates; it was, however, possible to overcome this limitation experimentally. In addition, it is shown that the hydrogenation reaction can be selectively induced in the presence of strongly dehydrogenated carbonaceous deposits, whereas the alternative reaction (H/D-exchange/isomerisation) can proceed also without the presence of those species; possible models for explanation are discussed. Finally, the possible origin of the different reaction rates with cis- and trans-2-butene that were observed only under certain reaction conditions is discussed.
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Eren, Murat Erkan. "Knowledge-sharing Practices Among Turkish Peacekeeping Officers." Thesis, University of North Texas, 2012. https://digital.library.unt.edu/ark:/67531/metadc149588/.
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The Turkish National Police (TNP) peacekeeping officers experience poor knowledge-sharing practices before, during, and after their tours of duty at the United Nations (UN) field missions, thus causing knowledge loss. The study aims to reveal the current knowledge-sharing practices of the TNP peacekeeping officers and proposes a knowledge-sharing system to share knowledge effectively. It also examines how applicable the knowledge management models are for their knowledge-sharing practices. In order to gain a better understanding about the knowledge-sharing practices of TNP officers, the researcher used a qualitative research method in this study. The researcher used semi-structured interviews in data collection. The participants were selected based on the non-probability and purposive sampling method. Content analysis and constant comparison was performed in the data analysis process. The most important knowledge sources of the peacekeeping officers are their colleagues, the Internet, and email groups. The peacekeepers recommend writing reports, organizing training programs, conducting exit interviews, adopting best practices, and creating a knowledge depository. The study uncovers that organizational culture, hierarchy, and physical proximity are significant factors that have a vital impact on knowledge sharing. Knowledge Conversion Model is substantially applicable for the knowledge-sharing practices of the TNP peacekeeping officer.