Dissertations / Theses on the topic 'Symmetric and Asymmetric supercapacitor'
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Liu, Chang. "Polyaniline and Graphene Based Symmetric and Asymmetric Solide-State Supercapacitor." University of Akron / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=akron1429622924.
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Bona, Claudine M. "Symmetric and asymmetric hybridization in citrus spp." [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-1326.
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Markesjö, Erik. "Different Replicator Equations in Symmetric and Asymmetric Games." Thesis, Uppsala universitet, Tillämpad matematik och statistik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-256172.
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Luehe, Karl von der. "Câ‚-symmetric phosphine-phospholane ligands for asymmetric hydrogenation." Thesis, University of Bristol, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.430205.
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Axe, Philip. "Pseudo-C3-symmetric titanium complexes for asymmetric catalysis." Thesis, University of Bath, 2008. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.512296.
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Tkaczyk, Karen McMillan. "Studies towards asymmetric hydroboration with C₂ symmetric dithiols." Thesis, University of Cambridge, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.625077.
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Lee, Jee Hea. "Authenticated encryption in the symmetric and asymmetric settings /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2001. http://wwwlib.umi.com/cr/ucsd/fullcit?p3022195.
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Herrero, Antón Rosa. "Hybrid methodologies for symmetric and asymmetric vehicle routing problems." Doctoral thesis, Universitat Autònoma de Barcelona, 2016. http://hdl.handle.net/10803/369581.
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En las últimas décadas, la globalización ha impulsado la adaptación del sector del Transporte y la Logística a las nuevas demandas sociales. Al mismo tiempo, el transporte ha sido la columna vertebral de la globalización. Esta necesidad social crea consumidores ambiciosos que necesitan sus productos de forma rápida y a un precio asequible muchas veces sin ser conscientes de su origen, el transporte o los aspectos medioambientales, entre otros factores. Sin embargo, para satisfacer las demandas del cliente, es necesario encontrar el modo de transporte más barato, que significa la mejora de la logística del transporte de estos productos. Por lo tanto, estas demandas requieren un servicio cada vez más flexible para satisfacer las necesidades del cliente, y, además, las empresas quieren un transporte eficiente y productivo.
Traveling Salesman Problems (TSP) and Vehicle Routing Problems (VRP) proporcionan el marco teórico para tratar este tipo de problemas logísticos relacionados con la distribución física de mercancías desde un almacén central hasta los clientes. Son dos de los problemas más desafiantes e investigados debido a su complejidad y aplicabilidad.
El objetivo principal de esta tesis doctoral es la introducción de metodologías híbridas que integran varias técnicas para resolver de manera eficiente rich VRPs con restricciones realistas. Esta tesis comienza con problemas teóricos y evoluciona hacia escenarios más realistas abordando un total de seis problemas combinatorios relacionados con el transporte por carretera.
Una metaheurística llamada Tailored Lagrangian Metaheuristic (TLM) se ha desarrollado para abordar el TSP. Está basa en la relajación de Lagrange que se utiliza para explotar la estructura del problema que reduce considerablemente su complejidad moviendo restricciones difíciles de satisfacer a la función objetivo, asociando una penalización en caso de que no se cumplen.
La metaheurística desarrollada para el TSP se ha integrado en dos metodologías híbridas combinadas con Constraint Programming para hacer frente a problemas más complejos. En primer lugar, el Capacitated Vehicle Routing Problem (CVRP), cuyos los vehículos tienen limitaciones de capacidad de carga de las mercancías que deben ser entregadas, es abordado. En segundo lugar, se ha abordado un problema real, Home Health Care (HHC), del servicio de Salud en el municipio de Ferrara, Italia. Este consiste en la asignación de los tratamientos de los pacientes a las enfermeras que viajan a las casas de los pacientes.
Investigaciones teóricas suelen asumir la simetría de los costes basados en la distancia de viajar de un lugar a otro y la existencia de una flota homogénea de vehículos con una misma capacidad. Esta tesis estudia diferentes variantes centradas en el impacto que causa la asimetría de los costes y la heterogeneidad de la flota. Para estos estudios, se abordan la versión con costes asimétricos del TSP y del CVRP -el Asymmetric Traveling Salesman Problem (ATSP) y el Asymmetric Capacitated Vehicle Routing Problem (ACVRP)- y la versión con flota heterogénea del ACVRP –el Asymmetric and Heterogeneous Vehicle Routing Problem (AHVRP).Over the last decades, globalization has driven the adaptation of the Transport and Logistics sector to new social demands. At the same time, transport has been the backbone of globalization. This social need creates ambitious consumers who need their products quickly and an affordable price often unaware of their origin, transport mode or environmental aspects, among other factors. Nevertheless, to satisfy customer demands, it is needed to find the cheapest transport mode, which in turn means the improvement of transport logistics of the products. Therefore, these demands require an increasingly flexible service to meet customer requirements, and in addition companies want an efficient and productive transport. The so called Traveling Salesman Problems (TSP) and Vehicle Routing Problems (VRP) provide the theoretical framework for approaching this class of logistic problems associated with the physical distribution of goods from a central depot to customers. They are two of the most challenging and researched problems because of their complexity and applicability. The main goal of this PhD thesis is to introduce hybrid methodologies that integrate several techniques to efficiently solve rich VRPs with realistic constraints. It starts with theoretical problems and evolves into more realistic scenarios tackling six combinatorial problems related to road transport. A metaheuristic named Tailored Lagrangian Metaheuristic (TLM) has been developed to tackle the TSP. It is based on the Lagrangian Relaxation which is used to exploit the structure of the problem reducing considerably its complexity by moving hard-to-satisfy constraints into the objective function, associating a penalty in case the constraints are not satisfied. The developed metaheuristic for the TSP has been integrated into two hybrid methodologies combined with Constraint Programming to tackle more complex problems. First of all, it is addressed the Capacitated Vehicle Routing Problem (CVRP), whose vehicles have limited loading capacity of the goods that must be delivered. Secondly, it has been addressed a real problem of the Home Health Care (HHC) service in the municipality of Ferrara, Italy. It consists on assigning patients' services to nurses which travel to each patient’s home. Theoretical researches typically assume the symmetry of the distance-based costs associated with traveling from one place to another as well as the existence of a homogeneous fleet of vehicles with limited capacity. This thesis studies different variants focusing on the impact that causes the asymmetry of the costs and the heterogeneity of the fleet. For these purpose, the Asymmetric Traveling Salesman Problem (ATSP), the Asymmetric Capacitated Vehicle Routing Problem (ACVRP) and the Asymmetric and Heterogeneous Vehicle Routing Problem (AHVRP) are addressed.
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Polak, Malwina Maria, and Marcelina Polak. "Modeling exchange rate using symmetric and asymmetric GARCH models." Thesis, KTH, Matematisk statistik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-195824.
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This paper attempts to study GARCH-type models, with emphasis on fitting GARCH models to exchange rate return series. The symmetric GARCH(1,1) model is compared with the asymmetric EGARCH(1,1) model. Both models are analysed with different conditional distributions, namely Normal, Student's t and skew Student's t for the return innovation. Parameter estimation is performed using a maximum-likelihood approximation. The model performance is assessed by looking at the lowest AIC and BIC. Four exchange rate returns are studied using daily data over the period from 2002 to 2015. Moreover, essential ideas of return time series and stylised facts will be analysed. Our results indicate that the asymmetric GARCH model improves generally estimation with fat-tailed densities in the conditional variance. Furthermore, persistence has found to be reduced with the use of heavy-tailed distributions. Asymmetry presence has been detected in the EGARCH model. Besides, we found that "good news" tend to increase volatility in comparison with "bad news".Syftet med uppsatsen är att studera modeller av GARCH-typ, och fokus ligger på att anpassa GARCH-modeller efter växelkurstidsserier. Den symmetriska GARCH(1,1)-modellen jämförs med den asymmetriska EGARCH(1,1)-modellen. Modellerna analyseras för olika fördelningar, såsom normal- och t-fördelning, på avkastningarnas brustermer. För att estimera parametrarna används maximum likelihood-metoden. Modellens prestanda bedöms sedan utifrån AIC- och BIC-kriterierna. Studien är baserad på daglig data från fyra valutapar under perioden 2002 till 2015. Resultaten indikerar att den asymmetriska GARCH-modellen förbättrar estimeringen generellt sett. Genom att använda tjocksvansade fördelningar finner man att persistensen minskar. EGARCH-modellen fångar dessutom upp asymmetrier i avkastningarna, på så sätt att volatiliteten ökar mer vid "goda nyheter" än vid "dåliga nyheter".
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Tenny, Roy. "Symmetric and asymmetric secure communication schemes using nonlinear dynamics /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2003. http://wwwlib.umi.com/cr/ucsd/fullcit?p3099554.
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Rafezy, Behzad. "Global vibration analysis of symmetric and asymmetric high rise buildings." Thesis, Cardiff University, 2004. http://orca.cf.ac.uk/55960/.
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This thesis presents two global analysis approaches to the calculation of the natural frequencies of high rise buildings. The structures are proportional and their component members are repeated at each storey level unless there is a step change of properties. Within this scope many geometric configurations can be encompassed, ranging from uniform structures with doubly symmetric floor plans to doubly asymmetric ones comprising plane frame and wall structures running in two orthogonal directions. The first method utilises a continuum element approach in which the structure is divided into segments by cutting through the structure horizontally at those storey levels corresponding to changes in storey properties. A typical segment is then replaced by an appropriate substitute beam that has uniformly distributed mass and stiffness. Subsequently, the governing differential equations of the substitute beam are formulated using the continuum approach and posed in the form of a dynamic member stiffness matrix that is exact to small deflection theory. Since the formulation allows for the distributed mass and stiffness of the member, it necessitates the solution of a transcendental eigenvalue problem. The required natural frequencies are thus determined using a cantilever model in conjunction with the Wittrick-Williams algorithm, which ensures that no natural frequencies can be missed. In addition, a two step process has been developed for certain asymmetric structures in which the natural frequencies corresponding to coupled motion between the planes of vibration can be obtained from the equivalent uncoupled ones through a simple cubic relationship. This enables coupled, three-dimensional vibration problems to be solved very efficiently using a two dimensional approach. The second method utilises the Principle of Multiples which, when applicable, enables any frame, regardless of the number of storeys or bays, to be simplified to an equivalent one bay frame, that has precisely the same natural frequencies. If the original frame does not fully satisfy the Principle, the same process can still be utilised, but the resulting substitute frame will yield approximate frequencies, although they will normally be acceptable to engineering accuracy. Like the first method, it can also be used for the vibration analysis of asymmetric, three-dimensional frame and wall-frame structures in a two-step procedure. First the analogous uncoupled system is analysed using substitute frames, then the relationship between the uncoupled and coupled responses is imposed through a cubic equation. Both of the above methods assume rigid floor diaphragms and require a knowledge of the building's static eccentricity at each storey level. The current methods of calculating this are cumbersome and even the definitions are open to dispute. A practical method of calculation is therefore presented and a small parametric study enables recommendations to be made. Overall, the proposed methods require little effort, offer clear and concise output and can sometimes yield solutions of sufficient accuracy for definitive checks, but more usually provide engineering accuracy for intermediate checks during tasks such as scheme development or remedial work. This claim is supported by the results of extensive parametric studies undertaken for this thesis. In all examples, the results from the proposed methods have been compared with the results of a full finite element analysis of the original structure obtained using the vibration programme ETABS. The exercise confirms that the proposed methods can yield results of sufficient accuracy for engineering calculations.
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Luo, Yunfei. "Chemoenzymatic synthesis of C2 symmetric chiral dienes for asymmetric catalysis." Thesis, University of Liverpool, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.539483.
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Clark, Kylen D. "A Numerical Comparison of Symmetric and Asymmetric Supersonic Wind Tunnels." University of Cincinnati / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1447071393.
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Doughty, Jeffrey Jon. "Symmetric Near-Field Probe Design and Comparison to Asymmetric Probes." PDXScholar, 2010. https://pdxscholar.library.pdx.edu/open_access_etds/390.
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Tip Enhanced Near-field Optical Microscopy (TENOM) is a method for optically imaging at resolutions far below the diffraction limit. This technique requires optical nano-probes with very specialized geometries, in order to obtain large, localized enhancements of the electromagnetic field, which is the driver behind this imaging method. Traditional methods for the fabrication of these nano-probes involve electrochemical etching and subsequent FIB milling. However, this milling process is non-trivial, requiring multiple cuts on each probe. This requires multiple rotations of the probe within the FIB system, which may not be possible in all systems, meaning the sample must be removed from vacuum, rotated by hand and placed back under vacuum. This is time consuming and costly and presents a problem with reproducibility. The method presented here is to replace multiple cuts from a side profile with a small number of cuts from a top down profile. This method uses the inherent imaging characteristics of the FIB, by assigning beam dwell times to specific locations on the sample, through the use of bitmap images. These bitmaps are placed over the sample while imaging and provide a lookup table for the beam while milling. These images are grayscale with the color of each pixel representing the dwell time at that pixel. This technique, combined with grayscale gradients, can provide probes with a symmetric geometry, making the system polarization independent.
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Wong, Wilson Wai Shun. "A CDMA based hybrid wireless architecture for symmetric and asymmetric communications." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0018/NQ53726.pdf.
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Lo, Michael Man-chu 1971. "Applications of C₂-symmetric bis(azaferrocenes) in asymmetric copper-catalyzed reactions." Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/8359.
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Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 2002.Vita.
Includes bibliographical references.
Based on a strategy developed in our group for the desymmetrization of planar heterocycles, we have designed, synthesized, and resolved a number of bidentate, C2-symmetric planar-chiral bis(azaferrocenes) that bear a structural resemblance to the highly versatile bis(oxazolines). These bis(azaferrocenes) have their stereogenic elements directly connected to their ligating atoms, which should help these heterocycles exert better stereodifferentiating ability when they are applied as ligands in metal-catalyzed processes. To validate the ligand design, we first applied our C2-symmetric bis(azaferrocenes) as ligands in the asymmetric copper-catalyzed cyclopropanation of olefins. We discovered that one of these ligands is particularly effective, and using a hindered diazo ester, an array of monosubstituted olefins has been cyclopropanated with excellent diastereo- as welf as enantioselectivity. The level of stereoselection achieved is comparable to some of the best ligands reported to date. Preliminary studies also showed that trans and trisubstituted olefins can be excellent substrates for the ligand. The same copper-bis(azaferrocene) complex also catalyzes the ring expansion of oxetanes into tetrahydrofurans with high stereoselection. In the optimization process, we have developed a new hindered diazo ester that may also prove useful in other asymmetric carbene transfer processes. With the catalyst controlling the stereochemistry of the newly established C2 carbon and the oxetane substrate defining the configuration at the C3 carbon, the ring expansion furnishes either diastereomer of a 3-substituted tetrahydrofuran-2-carboxylate with high stereoselectivity.
(cont.) The Kinugasa reaction, which is the copper-mediated reaction between nitrones and terminal alkynes, is an underexplored synthetic pathway to 2-azetidinones. Using a bis(azaferrocene) as the ligand, we have successfully improved the Kinugasa reaction in the following aspects: (1) the reaction is catalytic in copper; (2) the reaction gives high cis diastereoselectivity; and, (3) the reaction is highly enantioselective with a variety of nitrones and alkynes. Combined with a subsequent epimerization, our enantioselective process represents the first general, catalytic system for the Kinugasa reaction, which provides stereoselective access to all four of the possible isomers.
by Michael Man-chu Lo.
Ph.D.
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Zhang, Yingxin. "Symmetric signaling by an asymmetric 1 erythropoietin : 2 erythropoietin receptor complex." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/45211.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Biological Engineering Division, 2008.Includes bibliographical references (p. 43-46).
One erythropoietin molecule binds asymmetrically to two identical receptor monomers via erythropoietin site 1 and site 2, although it is unclear how asymmetry affects receptor activation and signaling. Here we report the computational design and experimental validation of two mutant erythropoietin receptors: one that binds only to erythropoietin site 1 but not site 2, and one that binds only to site 2 but not site 1. Expression of either mutant receptor alone in Ba/F3 cells cannot elicit a signal in response to erythropoietin, but when co-expressed, there is a proliferative response and activation of the JAK2 Stat5 signaling pathway. A truncated erythropoietin receptor with only one cytosolic tyrosine (Y343), on only one receptor monomer is sufficient for signaling in response to erythropoietin, regardless of the monomer on which it is located. The same results apply to having only one conserved juxtamembrane hydrophobic L253 or W258 residue, essential for JAK2 activation, in the full-length receptor dimer. We conclude that despite asymmetry in the ligand-receptor dimer interaction, both sides are competent for signaling, and we suggest that the receptors signal equally.
by Yingxin Zhang.
M.Eng.
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Montag, Peter Katsumi. "Modeling the formation of current sheets in symmetric and asymmetric reconnection." Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/119927.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Physics, 2018.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 103-109).
In this thesis we investigate the nature of magnetic reconnection using analytic and numerical methods. We consider configurations which are symmetric across the reconnection layer relevant to the Earth magnetotail, as well as configurations asymmetric in density and temperature across the reconnection layer, important to reconnection in Earth's dayside magnetopause. We develop an analytic model for the evolution of the electron phase space distribution function based on adiabatic invariants. We then apply this two model problems-Fermi acceleration and electron trapping-to extend previous results in these areas and model their effects on parallel heating. Following this, we run a battery of simulations of reconnection using particle in cell (PIC) codes at several different values of density asymmetry and guide field. These simulations reveal a number of regimes of current sheet formation, all of which are associated with significant anisotropic heating. Finally, we take a closer look at the case of antiparallel reconnection, where small levels of asymmetry cause significant shortening in the current sheet that develops at the midplane. Analysis of the data suggests an asymmetry in the firehose condition is the cause. Running another battery of simulations that adds a temperature asymmetry, we find that elongated current sheets will again form when the temperature asymmetry is large enough to restore balance in the firehose condition across the layer.
by Peter Katsumi Montag.
Ph. D.
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Chen, Xiaoyi. "Novel Conjugated Polymer Prepared by Electrochemical Polymerization as Active Material in Supercapacitor." University of Akron / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=akron1428325817.
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Kothdiwala, Ahmed Farouk. "Simulation and optimisation of asymmetric and symmetric compound parabolic concentrating solar collectors." Thesis, University of Ulster, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243738.
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Lightowler, Mark. "Synthesis of novel C₂ symmetric ketene equivalents for asymmetric Diels-Alder reactions." Thesis, University of Bath, 1993. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334700.
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Isbiliroglu, Yigit D. "Coupled Soil-Structure Interaction Effects of Symmetric and Asymmetric Buildings In Urban Regions." Research Showcase @ CMU, 2013. http://repository.cmu.edu/dissertations/268.
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This thesis deals with the response of idealized building clusters during earthquakes, their effect on the ground motion, and how individual buildings interact with the soil and with each other. We simulate the ground motion during the 1994 Northridge earthquake and focus on the coupled response of multiple simplified symmetric and asymmetric building models located within the San Fernando Valley and the Simi Valley. We use the Domain Reduction Method (DRM) in order to perform these simulations efficiently while recurrently modifying the models without having to redo the entire simulation every time. Numerical results show that the soil-structure interaction (SSI) effects vary with the number and dynamic properties of the buildings, their separation, and the impedance with respect to the soil. These effects appear as: (i) an increased spatial variability of the ground motion; and (ii) significant reductions in the buildings’ base motion at high frequencies, changes in the higher natural frequencies of the building-foundation systems and variations in the roof displacement, with respect to those of the corresponding rigid-base and single SSI models. Torsional coupling of the asymmetric structures combined with SSI effects are also investigated, and results, in comparison with the symmetric structures, are given.
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Raya, Lilysuriazna Binti. "A metaheuristic ant colony optimization algorithm for symmetric and asymmetric traveling salesman problems." Thesis, Brunel University, 2018. http://bura.brunel.ac.uk/handle/2438/17617.
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This research addresses solving two types of Travelling Salesman Problems (TSP) which are the symmetric TSP (STSP) and the asymmetric TSP (ATSP). The TSP is a problem of finding a minimal length closed tour that visits each city once. If the distances between each pair of cities are the same in both directions, the problem is a STSP, otherwise, it is an ATSP. In this thesis, a new metaheuristic algorithm which is based on Ant Colony Optimization (ACO) is proposed to solve these problems. The key idea is to enhance the ability of exploration and exploitation by incorporating a metaheuristic approach with an exact method. A new strategy for creating 'Intelligent Ants' is introduced to construct the solution tours. This strategy aims at reducing the computational time by heuristically fixing part of the solution tour and improving the accuracy of the solutions through the usage of a solver, specifically for large size instances. Moreover, this proposed algorithm employs new ways of depositing and evaporating pheromone. A different approach of global updating of pheromone is proposed in which the pheromone is deposited only on the edges belonging to the colony-best ant and evaporated only on the edges belonging to the colony-worst ant that are not in the colony-best ant. Additionally, the parameters of the proposed algorithm which include the number of colonies, the number of ants in each colony, the relative influence of the pheromone trail α and the pheromone evaporation rate ρ are expressed as a function of the problem size. Comparisons with other sets of parameter values suggested in the literature have been investigated which illustrate the advantages of the choice of the proposed parameter settings. Further, in order to evaluate the performance of the proposed algorithm, a set of standard benchmark problems from the TSPLIB with up to 442 cities were solved and the results obtained were compared with other approaches from the literature. The proposed algorithm has proven to be competitive and shows better performance in 63% of the 16 algorithms in terms of solution quality and obtained the optimum solutions in 70% of the 33 instances, proving that it is a good alternative approach to solve these hard combinatorial optimisation problems.
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Watts, Nicola Louisa. "Improving the scope and understanding of the Symmetric and Asymmetric Suzuki coupling reaction." Thesis, University of East Anglia, 2012. https://ueaeprints.uea.ac.uk/48116/.
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Investigations into the Symmetric and Asymmetric Suzuki cross-coupling reaction have been described. A new reaction protocol has been developed in which isolated pre-activated sodium trihydroxyarylborate salts were employed as the organoboron coupling partner, resulting in a more convenient and stoichiometrically efficient process. This alternative protocol has been applied to symmetric Suzuki reactions employing simple electron-rich and electron-poor aryl halide partners, and to sterically challenging Suzuki reactions employing bulkier substrates. Asymmetric (atroposelective) Suzuki coupling reactions were also successfully performed using sodium trihydroxyarylborate salts as coupling substrates. The versatility of these species as general organoboron reagents was also demonstrated by their successful application in a rhodium-catalysed 1,4-addition reaction. Experimental studies of asymmetric Suzuki cross-couplings towards axially chiral biaryl products have also been detailed. Model reactions towards configurationally stable biaryl products were found to undergo a successful chiral induction with the use of chiral ferrocenyl ligand (R)-(S)-PPFA 180, with high enantiomeric excesses achieved in some cases. Investigations into the possible influences on the asymmetric induction process exerted by the electronic and steric properties of the coupling partners were carried out, involving repeat asymmetric reactions towards the biaryl product 1-(2’-nitrophenyl)-2-phenylnaphthalene 179. In these reactions, changes to the reacting moiety of the coupling substrates were tested, with an additional reaction carried out involving the reversal of the organic group borne by each substrate.
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Helt, Kimberly M. (Kimberly Mae). "Network Analysis of the Symmetric and Asymmetric Patterns of Conflict in an Organization." Thesis, University of North Texas, 1993. https://digital.library.unt.edu/ark:/67531/metadc501212/.
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Missing from extant conflict literature is an examination of both symmetric and asymmetric conflict ties. To address this void, network analysis was utilized to examine the responses (both symmetric and asymmetric conflict ties) of 140 employees and managers in four divisions of a large agency of the Federal Government. The study was limited to conflict over scarce resources. Conflict management methods were examined as well as the perceptions of how respondents both cope with and feel about conflict. The results indicate that when two people in a conflict setting are structurally equivalent they both report actions and feelings that are opposite from those of- the other person. This finding, an inverse contagion effect, has been termed diffusion resistance.
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Benson, Richard. "A dosimetric analysis of the varian enhanced dynamic wedge for symmetric and asymmetric configurations." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=19254.
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Clinical use of shaped mega-voltage photon beams in the treatment of cancer has become an essential component of contemporary treatment with an ever-increasing reliance on plans that include computer controlled temporal and spatial shaping of the beam aperture. One such dynamic technique involves the use of the Enhanced Dynamic Wedge (EDW), which modulates the radiation dose across one axis of a rectangular field via the movement of a collimator jaw under computer control. The majority of clinical applications of this technique employ a field that is either symmetric and centered upon the central axis of the beam or involves a "half-blocked" field extending from the central axis out some distance. However there are many situations in which an off-axis (asymmetric) field would be optimal (e.g. for extremities or plans with multiple planning target volumes are irradiated from a single gantry angle) so it is necessary to understand the effect of moving the center of the EDW shaped field off the axis. In this study we have investigated the variance between the treatment planning system and the dose predicted according to the current clinical model. A procedure has been devised to correct for these variances and bring the predictions into agreement with one another (and with measurements in phantom).L'usage clinique de rayons de photon de méga-tension formés dans le traitement de cancer est devenu un composant essentiel de traitement contemporain avec une confiance jamais-qui augmente sur les projets qui incluent l'ordinateur moulage contrôlé, temporel et spatial de l'ouverture de rayon. Une telle technique dynamique implique l'usage du Enhanced Dynamic Wedge (EDW), qui module la dose de rayonnement à travers un axe d'un champ rectangulaire via le mouvement d'une mâchoire de collimator sous le contrôle informatique. La majorité d'applications cliniques de cette technique emploie un champ qui est ou symétrique et centré sur l'axe central du rayon ou implique un le champ moitié-bloqué s'étendant de l'axe central hors quelque distance. Cependant il y a beaucoup de situations dans lesquelles un d'-axe (asymétrique) le champ serait optimal (par ex pour les extrémités ou les projets avec les volumes de cible de planification de multiple sont irradié d'un angle de portique seul) si c'est nécessaire de comprendre l'effet de déménagement du centre du champ en forme d'EDW de l'axe. Dans cette étude nous avons examiné la variance entre le traitement planifiant le système et la dose prédite selon le modèle clinique actuel. Une procédure a été conçue pour rectifier ces variances et amène les prédictions dans l'accord avec l'un l'autre (et avec les mesures dans le fantôme). fr
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Zhang, Rui, and 張瑞. "Asymmetric organic oxidation by chiral ruthenium complexes containing D2 and D4 symmetric porphyrinato ligands." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B42576246.
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Atmander, Elias. "FEDERAL FUNDS RATE ON BITCOIN VOLATILITY : Using the symmetric GARCH and asymmetric EGARCH models." Thesis, Umeå universitet, Nationalekonomi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-184979.
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This thesis examines the volatility of Bitcoin during four years from 2014-04-01 until 2020-04-01. The main objective of the thesis was to answer the research question: “Is the return volatility of Bitcoin affected by interest rate change announcements by the FOMC?” and given Bitcoin’s decentralized characteristics, the hypothesis to this was that Bitcoin should not be affected by such changes. The GARCH (1,1) and EGARCH (1,1) models were used to analyze the transformed logarithmic returns of Bitcoin. The number of observations sum to 1462 observations (days). Additionally, 13 observations of change announcements in the federal funds rate were used with a dummy variable approach to analyze for effects on Bitcoin volatility. The main findings of this thesis indicate that Bitcoin is not affected by announcements of a change in the federal funds rate, and thus, the hypothesis that Bitcoin is immune to changes in the federal funds rate is supported.
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Zhang, Rui. "Asymmetric organic oxidation by chiral ruthenium complexes containing D2 and D4 symmetric porphyrinato ligands." Click to view the E-thesis via HKUTO, 2000. http://sunzi.lib.hku.hk/hkuto/record/B42576246.
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Islam, Naveed. "Cryptography based Visual Data Protection." Thesis, Montpellier 2, 2011. http://www.theses.fr/2011MON20178/document.
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La transmission de données multimédia sur les réseaux sécurisés a une croissance exponentielle grâce aux progrès scientifique dans les technologies de l'information et de la communication. La sécurité des données dans certaines applications comme le stockage sécurisé, l'authentification, la protection des droits d'auteurs, la communication militaire ou la visioconférence confidentielles, nécessitent de nouvelles stratégies en matière de transmission sécurisée. Deux techniques sont couramment utilisées pour la transmission sécurisée de données visuelles, à savoir : la cryptographie et la stéganographie. La cryptographie sécurise les données en utilisant des clés secrètes afin de rendre les données illisibles, la stéganographie, elle, vise à insérer des données cruciales dans des signaux porteurs anodins.De plus, pour la confiance mutuelle et les systèmes distribués, le partage sécurisé de ressources est souvent une garantie suffisante pour les applications de communication. L'objectif principal de cette thèse est de réaliser une protection des données visuelles, en particulier les images numériques, par le biais des techniques modernes de cryptographie. Dans ce contexte, deux objectifs de recherche ont été développés durant ces travaux de thèse.La première partie de notre travail se concentre sur la sécurité des images numériques dans un environnement partagé. Ensuite, la deuxième partie porte sur l'intégrité des données visuelles pendant une transmission sécurisée.Nous avons proposé un nouveau schéma de partage des images qui exploite les propriétés d'addition et de multiplication homomorphique de deux crypto systèmes à clé publique largement utilisés : les algorithmes RSA et Paillier. Dans les schémas traditionnels de partage sécurisé, le ``dealer'' partitionne le secret en parties et le distribue à chacun des autres acteurs. Ainsi, aucun des acteurs impliqués ne participe à la création du partage sécurisé, mais il est toujours possible que le ``dealer'' transmette des données malveillantes. Au contraire, l'approche proposée utilise le système de partage de secret d'une manière qui limite l'influence du ‘‘dealer'' sur le protocole en permettant à chaque acteur de participer.La deuxième partie de ces travaux de thèse met l'accent sur l'intégrité des données visuelles lors de la transmission. L'intégrité des données signifie que les données gardent leurs structures complètes au cours d'une opération numérique comme le stockage, le transfert ou la récupération. Le changement d'un seul bit de données cryptées peut avoir un impact catastrophique sur les données décryptées. Nous abordons le problème de correction d'erreurs dans les images cryptées en utilisant le chiffrement à clé symétrique AES (Advanced Encryptions Standard) suivant différents modes. Trois mesures sont proposées afin d'exploiter les statistiques locales des données visuelles et l'algorithme de chiffrement, dans l'objectif de corriger les erreurs efficacementDue to the advancements in the information and communication technologies, the transmission of multimedia data over secure or insecure communication channels has increased exponentially. The security of data in applications like safe storage, authentications, copyright protection,remote military image communication or confidential video-conferencing require new strategies for secure transmission. Two techniques are commonly used for the secure transmission of visual data, i.e. cryptography and steganography. Cryptography achieves security by using secret keysto make the data illegible while steganography aims to hide the data in some innocent carrier signal. For shared trust and distributed environment, secret sharing schemes provide sufficient security in various communication applications. The principal objective of this thesis is to achieveprotection of visual data especially images through modern cryptographic techniques. In this context, the focus of the work in perspective, is twofolded. The first part of our work focuses on the security of image data in shared environment while the second part focuses on the integrity ofimage data in the encrypted domain during transmission.We proposed a new sharing scheme for images which exploits the additive and multiplicative homomorphic properties of two well known public key cryptosystems, namely, the RSA and the Paillier. In traditional secret sharing schemes, the dealer partitions the secret into shares and distributethe shares to each of the player. Thus, none of the involved players participate in the creation of the shared secret and there is always a possibilitythat the dealer can cheat some player. On the contrary, the proposed approach employs the secret sharing scheme in a way that limits the influence of the dealer over the protocol by allowing each player to participate. The second part of our thesis emphasizes on the integrity of visual data during transmission. Data integrity means that the data have its complete structure during any operation like storage, transfer or retrieval. A single bit change in encrypted data can have catastrophic impact over the decrypted data. We address the problem of error correction in images encrypted using symmetric key cryptosystem of the Advanced Encryption Standard (AES) algorithm. Three methods are proposed to exploit the local statistics of the visual data and the encryption algorithm to successfully correct the errors
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Latulipe, Celine. "A Symmetric Interaction Model for Bimanual Input." Thesis, University of Waterloo, 2006. http://hdl.handle.net/10012/2915.
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People use both their hands together cooperatively in many everyday activities. The modern computer interface fails to take advantage of this basic human ability, with the exception of the keyboard. However, the keyboard is limited in that it does not afford continuous spatial input. The computer mouse is perfectly suited for the point and click tasks that are the major method of manipulation within graphical user interfaces, but standard computers have a single mouse. A single mouse does not afford spatial coordination between the two hands within the graphical user interface. Although the advent of the Universal Serial Bus has made it possible to easily plug in many peripheral devices, including a second mouse, modern operating systems work on the assumption of a single spatial input stream. Thus, if a second mouse is plugged into a Macintosh computer, a Windows computer or a UNIX computer, the two mice control the same cursor. Previous work in two-handed or bimanual interaction techniques has often followed the asymmetric interaction guidelines set out by Yves Guiard's Kinematic Chain Model. In asymmetric interaction, the hands are assigned different tasks, based on hand dominance. I show that there is an interesting class of desktop user interface tasks which can be classified as symmetric. A symmetric task is one in which the two hands contribute equally to the completion of a unified task. I show that dual-mouse symmetric interaction techniques outperform traditional single-mouse techniques as well as dual-mouse asymmetric techniques for these symmetric tasks. I also show that users prefer the symmetric interaction techniques for these naturally symmetric tasks.
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Hartl, Johannes [Verfasser], and Lutz [Akademischer Betreuer] Arnold. "Corporate underinvestment in the presence of symmetric and asymmetric information / Johannes Hartl. Betreuer: Lutz Arnold." Regensburg : Universitätsbibliothek Regensburg, 2012. http://d-nb.info/1026165539/34.
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Hawkins, Joel Michael. "Three new C̲₂ symmetric chiral auxiliaries for metal mediated asymmetric reactions : studies in asymmetric carbon-hydrogen, carbon-nitrogen, and carbon-oxygen bond formation." Thesis, Massachusetts Institute of Technology, 1986. http://hdl.handle.net/1721.1/15198.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 1986.MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE
Bibliography: leaves 110-116.
by Joel Michael Hawkins.
Ph.D.
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Lake, Fredrik. "C2- and C3-symmetric ligands via ring-opening of aziridines." Doctoral thesis, KTH, Chemistry, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3424.
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This thesis deals with the design and synthesis of chiralenantiopure nitrogencontaining ligands and the use of theseligands in asymmetric catalysis. A modular synthetic approachto enantiopure nitrogen-containing ligands was developed. Thesynthetic method is based on the ring-opening of activatedchiral aziridines by nitrogen nucleophiles. The aziridines areconveniently prepared from amino alcohols. The structure oftheaziridine and of the nucleophile can be extensively varied andlibraries of ligands are easily prepared. The use of primaryamines affords C2-symmetric bis(sulfonamides), whereas the use ofammonia affords C3-symmetric tris(sulfonamides) that can beelaborated into the corresponding tetra-amines.
The C2- and C3-symmetric ligands were used in the asymmetrictitaniummediated addition of diethylzinc to benzaldehyderesulting in modest enantioselection, 76% ee. A thoroughinvestigation of the reaction conditions revealed that theamount of Ti(OiPr)4has a decisive effect on the reaction rate and thestereochemical outcome of the reaction. The reaction timedecreased from about 90 hours to 15 minutes and theenantioselectivity changed from 26% of the (R)- enantiomer to72% of the (S)-enantiomer when the Ti(OiPr)4:benzaldehyde ratio was increased from 0.125:1 to1.48:1. Moreover, the titanium-mediated addition of diethylzincto benzaldehyde was studied in the presence of chiraladditives. The bis(sulfonamides) were also used in thecyclopropanation of cinnamyl alcohol. However, only lowenantioselection was observed, 27% ee.
The C3-symmetric tetra-amines were reacted to formazaphosphatranes. These weak acids were only partiallydeprotonated by the strong base KOtBu to form the correspondingproazaphosphatranes. The unexpectedly strong basicity of theproazaphosphatranes was believed to be due to steric effects assuggested by DFT calculations. The tetra-amines and thesulfonamides were used for the preparation of metal complexesof Lewis acidic metals such as titanium(IV) andzirconium(IV).
Keywords:asymmetric catalysis, aziridine, benzaldehyde,diethylzinc, enantioselective, ligand, proazaphosphatrane,ring-opening, sulfonamide, symmetry, titanium, zirconium
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Böhnisch, Torben. "C2-Symmetric Pyrazole-Bridged Ligands and Their Application in Asymmetric Transition-Metal Catalysis." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2015. http://hdl.handle.net/11858/00-1735-0000-0028-876A-6.
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Rigotti, Thomas. "Synthesis and metal complexes of C2 symmetric ligands obtained from (R)-(+)-Betti and dialdehydes for asymmetric induction reactions." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amslaurea.unibo.it/9335/.
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The aim of this master’s research thesis was the employment of an enantiopure 1,3-aminoalcohol, the 1-(α-aminobenzyl)-2-naphthol, known as Betti base, for the synthesis of some novel compounds which show a C2 symmetry. Some of these compounds, after derivatization, were used as ligands in association with transition metals to prepare some catalysts for enantioselective catalytic reactions. Some aminoalcohol (Salan-type) derivatives of these compounds were obtained upon reduction and in some cases it was possible to obtain complexes with transition metals such as Mn, Ni, Co and Cu. Furthermore a novel 6-membered analogue bisoxazoline ligand, 2,6-bis((R)-1-Phenyl-1H-naphtho[1,2-e][1,3]oxazin-3-yl)pyridine, was obtained and from it two Cu-complexes were prepared. The metal complexes were employed in some reactions to test the asymmetric induction, which was in some cases up to discrete values.
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Hassan, Syed. "Exchange rate volatility, UK imports and the recent financial crisis : evidence from symmetric ARDL and asymmetric ARDL methods." Thesis, University of Southampton, 2014. https://eprints.soton.ac.uk/373083/.
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Uncertainty in the amount and direction of changes in exchange rates is described as the exchange rate volatility. This research examines the role of exchange rate volatility in determining the UK’s real imports in a broader perspective by including: i) the third country exchange rate volatility; and ii) the impact of the current financial crisis on the relationship between exchange rate volatility and UK imports. In the context of international trade, exchange rates are often more important than the prices of the traded goods and services because the prices are observed to be more stable and predictable in comparison to the exchange rate movements. Thus, a rise in exchange rate volatility causes an increase in the degree of risk aversion of the traders, which results in the reduction of trade volume. This research contributes to the empirical literature on the subject by offering evidence based on the Symmetric ARDL bounds testing approach (Pesaran, Shin and Smith, 2001) and the Asymmetric ARDL method (Shin et al., 2013). These models are capable of addressing important issues related to the non-stationary and nonlinear characteristics of the underlying macroeconomic data. The analysis sample includes the UK’s major trading partners, i.e. the US, Germany and Japan representing the developed countries and Brazil, China and South Africa representing the developing economies. Results suggest that exchange rate volatility plays an important role, and also reveal that there is a significant effect from the recent financial crisis on UK imports. This finding is consistent when we test for the third country volatility effect. We also find that there is a significant causal relationship between exchange rate volatility and UK imports, both in bilateral tests and in tests that account for the third country exchange rate volatility. Comparative analysis of developed and developing countries shows that the third country effect is significant for all the countries. The UK imports’ demand elasticity to different determinant variables, including exchange rate volatility, changes significantly after the inclusion of the financial crisis. These changes are more pronounced under the Asymmetric ARDL method, where positive and negative changes in determinant variables, especially exchange rate volatilities, affect UK imports differently before and after inclusion of the financial crisis. These findings contribute to the existing literature as no evidence of the third country effect and asymmetric behavior of exchange rate volatility on UK trade flows currently exists in the literature. This has significant implications for trade policy and international trade to minimise the underlying risk factors and ensure stable trade flows in different economic scenarios.
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Wang, Zhao. "Synthesis of Polyhedral Oligomeric Silsesquioxane(POSS)-Based Shape Amphiphiles with Two Polymeric Tails of Symmetric or Asymmetric Compositions." University of Akron / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=akron1366825911.
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Falch, Wenche. "Står til tjeneste : Emosjonelt arbeid i tjenestemøtet." Doctoral thesis, Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-6225.
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This thesis is about personal assistants, and how they experience their work. The aim of this study is twofold: First to examine the experiences of personal assistants and their work. Second, to examine the assistant’s experiences of feelings at work and how these feelings are managed from an emotionsociological perspective. The empirical base of the research builds upon interviews with personal assistants with a focus on the individual and subjective experiences of the work. The data shows that the assistants concentrate on the emotional aspects of their job. When asked to describe their work situation, the interviewees were preoccupied with the regulation of their own feelings in the relation to the employer. The analysis has an abductive approach, in which empirical sensitivity, interpretation and theory are combined. In terms of results, this study shows that the majority of assistants experience themselves as a friend to the client and they experience the job as meaningful. However, here lies the duplicity of the situation because being a friend to the client, who is also the supervisor, can lead to problems when setting the boundaries for intimacy. The study also shows relatively stable structures in relation to the dimensions of power and subordination, where the assistants’ experience themselves as subordinates and the client as superior. At the same time that the assistants finds purpose in their job there are also challenges connected to being subordinate in a face-to-face situation. It is important to the assistants to have control over feelings and outward expressions. Feelings of subordination seem to be linked to the status and power the assistants have in society at large. Thus, how vulnerable they are in the subordinate position depends on age, gender and education. Another effect described by the assistants is a kind of emotional dissonance, where their own feelings are in conflict with how they wish to act in the social interaction with the clients. In the final chapter the concepts of asymmetric and symmetric interaction are used to understand different types of feelings the assistants’ experience. The asymmetric interaction can trigger feelings of irritation, frustration and anger which are energy draining. Symmetric interaction often seems to lead to feelings of contentment, joy and purpose, which are uplifting and energy renewing. As a concluding remark emotional labour seems to be a significant part of the assistants work. By using an emotionsociological perspective it has been possible to gain knowledge about different aspects of the personal assistants’ emotional labour.
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Otomaru, Yusuke. "Preparation of new C2-symmetric chiral diene ligands and their use for rhodium-catalyzed asymmetric addition of organoboron reagents." 京都大学 (Kyoto University), 2005. http://hdl.handle.net/2433/144596.
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Kameda, Minoru. "Molecular design of N-spiro C2-symmetric chiral phase-transfer catalysts for practical asymmetric synthesis of α-amino acids." 京都大学 (Kyoto University), 2004. http://hdl.handle.net/2433/147838.
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Tsai, Mei-Hsuan. "Boron containing molecular imprinted polymer (MIP) templates from symmetric and asymmetric diboration of olefins and other boron containing functional polymers." Thesis, University of Cambridge, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.608235.
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Gilbert, Edouard. "Optimisation de supercondensateurs à électrolyte organique." Thesis, Orléans, 2010. http://www.theses.fr/2010ORLE2043.
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Les supercondensateurs à base de carbones activés sont caractérisés par une puissance et une cyclabilité supérieures à celles des batteries. Toutefois, en raison de leur faible densité d’énergie, ils sont principalement utilisés comme source de stockage secondaire. Les objectifs de cette thèse étaient d’augmenter l’énergie des supercondensateurs fonctionnant en milieu organique (TEABF4/AN) et de comprendre la répartition des ions dans les pores des carbones activés avant et après la charge des supercondensateurs. Deux approches ont été suivies pour répondre au premier objectif. D’abord nous avons cherché à augmenter la capacité volumique des carbones à 90 F/cm3. Parmi les carbones étudiés, un carbone a attiré notre attention en raison de sa densité d’électrode et de sa capacité élevées. Toutefois, un traitement thermique s’est avéré nécessaire pour réduire la fonctionnalité de surface altérant principalement les performances en vieillissement. Le carbone ainsi traité présente une capacité volumique de 88 F/cm3. Aussi, en s’appuyant sur le principe d’égalité des charges, nous avons mis en place plusieurs systèmes asymétriques carbone/carbone avec des masses et/ou des carbones différents aux deux électrodes. Les configurations optimales permettent de déplacer la fenêtre de stabilité vers des potentiels plus faibles. Les bonnes performances en vieillissement des systèmes asymétriques en masse réalisés au laboratoire nous ont encouragés à réaliser des essais préliminaires sur des composants industriels. Il a ainsi été montré que la dissymétrie de masse permet de ralentir le vieillissement à 2,7 V par rapport à un système symétrique standard. Les analyses RMN de la poudre d’électrodes imprégnées d’électrolyte montrent que les ions et le solvant occupent la porosité en l’absence de polarisation. L’étude des électrodes chargées a montré que les ions se réorganisent dans la porosité. A l’électrode négative, le solvant est exclu de la porosité et les ions TEA+ pénètrent sans leur sphère de solvatation. A l’électrode positive, il reste du solvant, ce qui suggère que les ions BF4 - sont partiellement solvatés dans la microporosité. En augmentant la tension de charge, la quantité d’ions TEA+ and BF4 - augmente respectivement dans les électrodes négative et positive; toutefois des contre-ions restent présents même à tension élevéeSupercapacitors based on activated carbons are characterized by higher power and cycle life than batteries. Due to their low energy density, they are mainly used as secondary storage device. The objectives of this thesis were to improve the energy density of supercapacitors operating in organic electrolyte (TEABF4/AN) and to elucidate the distribution of ions in the pores of activated carbons, before and after the charge of supercapacitors. Two approaches were followed to reach the first objective. First, it has been attempted to increase the volumetric capacitance up to 90 F/cm3. One carbon giving a high electrode density and capacitance, but having a high amount of oxygenated functionalities, has been identified. It was thermally treated under reducing atmosphere to depress the functionalities which negatively impact the ageing of supercapacitors. The post-treated carbon displayed a volumetric capacitance of 88 F/cm3. Asymmetric carbon/carbon supercapacitors, with different mass or/and different carbons for the electrodes, were constructed for shifting the stability window towards lower potential values. Laboratory cells built in these conditions exhibited promising performance during cycling, which encouraged us to confirm the results at industrial scale. In particular, the asymmetric configuration using electrodes of different mass showed better ageing behavior at 2.7 V that the symmetric system. RMN analysis of the powder from electrodes soaked with the organic electrolyte showed that the solvent and ionic species are already confined into the micropores without applying any polarisation. During charging, the solvent molecules are expelled from the porosity of the negative electrode while TEA+ ions penetrate into the pores without their solvation shell. On the contrary, the presence of some solvent together with BF4 - in the positive electrode indicates that the BF4 - ions are partially solvated. Upon increasing the voltage, the amount of TEA+ and BF4 - increases in the negative and positive electrode, respectively; however, counter ions are still present even at high voltage
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Liu, Chang. "The design, synthesis of potential sialidase inhibitors as anti-influenza drugs and synthesis of C-2 symmetric ligands for transition metal catalyzed asymmetric reduction reactions." Diss., Connect to online resource - MSU authorized users, 2006.
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Wen, Miao. "Chemical analysis and biosynthesis of secondary alcohols in plant cuticular waxes." Thesis, University of British Columbia, 2009. http://hdl.handle.net/2429/4304.
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The biosynthesis of wax components containing secondary functional groups was investigated in the current study. Two fundamentally different pathways were proposed to introduce the secondary functional groups. One pathway involves hydroxylation of elongated substrates. Wax components characterized by two functional groups located on or near the centre of the carbon chain, nonacosane-14,15-diol, -14,16-diol and -13,15-diol as well as corresponding ketols were identified for the first time in Arabidopsis stem wax. The alkanediols and ketols were dominated by the C-14,15 isomers. The absence of alkanediols and ketols in Arabidopsis mah1 mutants that are deficient in secondary alcohol biosynthesis confirmed the biosynthetic relationship between secondary alcohols and alkanediols/ketols (Chapter 3). In pea (Pisum sativum) leaf wax, two novel compound classes were identified as primary/secondary alcohols dominated by octacosane-1,14-diol and secondary/secondary alkanediols hentriacontane-9,16-diol, -8,15-diol and -10,17-diol. Co-localization of the secondary/secondary alkanediols and hentriacontan-15-ol and -16-ol pointed to a biosynthetic relationship (Chapter 4). The diverse structures of compounds identified in the current study suggested that hydroxylases can use substrates other than alkanes. The predominance of isomers within homologues indicated a regiospecificity of the hydroxylases involved in wax biosynthesis.
In addition to hydroxylation, secondary functional groups could also be introduced through elongation of carbon chains. Homologous series of 5-hydroxyaldehydes (C₂₄ and C₂₆-C₃₆) and 1,5-alkanediols (C₂₈-C₃₈) were identified in yew (Taxus baccata) needle wax. The relative position of both functional groups suggested that these two compound classes are biosynthetically related and their secondary functional groups are introduced during elongation (Chapter 5). The results of incubation of ¹⁴C-labeled malonyl-CoA and acyl-CoAs with different chain lengths in the presence of California poppy (Eschscholzia californica) microsomes provided the first evidence to support the elongation hypothesis. The results indicated that a carbonyl group rather than a hydroxyl group is introduced during elongation. To provide molecular tools for further investigations of the hypothetical pathway, three full length cDNAs encoding putative KCSs were cloned and one of them, PKCSI, was functionally characterized.
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Gunell, Joachim, and Jonas Kolijn. "Varför underprissätts nyintroduktioner? : En empirisk utredning av teoretisk diskrepans - bevis från Sverige." Thesis, Linköpings universitet, Företagsekonomi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-129944.
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Bakgrund och problem: Underprissättning har länge studerats, och fenomenet har konstaterats förekomma i en absolut majoritet av de studerade länderna. Trots detta råder ingen konsensus kring vilka teorier som förklarar underprissättning. Teorier för underprissättning är i huvudsak indelade i teorier baserade på symmetrisk eller asymmetrisk information, och de empiriska resultat som presenterats målar en spretig bild med resultat som går både emot och ger stöd för flera teorier. Mot bakgrund av den motstridighet som föreligger för teoretiska förklaringar till underprissättning har vi valt att studera ämnet noggrannare. Syfte: Studiens syfte är att, med utgångspunkt i motsägande empiriska resultat, utreda vilka olika teoretiska incitament som kan förklara underprissättning för att skapa en bättre förståelse för den komplexitet som föreligger inom teoribildningen för underprissättning. Metod: Vi applicerar i studien en kvantitativ forskningsmetodik där vi, i linje med internationella referensstudier, väljer att använda en multipel regressionsanalys med minstakvadrat-metoden för att kunna testa vilka teorier som är applicerbara för att förklara underprissättning. Vi approximerar teorierna via variabler med tillhörande hypoteser för att mäta dess individuella och ackumulerade effekt på underprissättning. Via hypotesprövning möjliggör vi en koppling mellan det statistiska resultatet och respektive teori. Slutsats: Studiens resultat stödjer såväl teorier baserade på symmetrisk som asymmetrisk information vilket illustrerar komplexiteten i fenomenet underprissättning. Med utgångspunkt i resultaten av den statistiska modellen förs en analys där teorier frikopplats från symmetri respektive asymmetri, och istället analyserats simultant. Denna analys presenterar en alternativ syn på teori kring underprissättning, där teorier tillhörande symmetrisk respektive asymmetrisk information inte är ömsesidigt uteslutande, vilket introducerar ett nytt sätt att se på teoretiska förklaringar för underprissättning.Background and problem: Underpricing has been subject to studies for many years, and the phenomena have been observed on a vast majority of studied countries. Despite the fact that studies have been conducted, there is no consensus as to which theories might best explain underpricing. Theories explaining underpricing are mainly divided into either symmetric or asymmetric information, and the empirical results presented testifies to the theoretical discrepancy, with support for and against several theories. The theoretical discrepancy is the main reason as to why we choose to closer examine the phenomena. Purpose: The purpose of this study is, based upon contradictory empirical results, to investigate as to which different theoretical incentives can explain IPO underpricing in order to create a better understanding of the complexity regarding theory for IPO underpricing. Methodology: In the study we apply a quantitative research method in which we, similar to international reference studies, use a multiple regression analysis with an ordinary least squares approach in order to test which theories are applicable in order to explain underpricing. We approximate the theories using variables with belonging hypotheses to quantify the variables individual and accumulated effect on underpricing. Using hypothesis testing we enable a connection between the statistical results and theories explaining underpricing. Conclusions: The study’s result support both theories based upon symmetric and asymmetric information which illustrates the complexity of the phenomenon of underpricing. Based on the statistical results the authors conduct an analysis in which theories are discarded from the context of symmetric and asymmetric information and are instead analyzed simultaneously. This analysis presents an alternative view of underpricing theories, in which theories belonging to symmetric as well as asymmetric information no longer are mutually excluding, which introduces a new approach to theoretical explanations for IPO underpricing.
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Zhu, Beibei. "Three Essays on Employer Learning and Statistical Discrimination." Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/23168.
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This dissertation consists of three essays studying employer learning and statistical discrimination of young workers in the U.S. labor market. The first chapter outlines the dissertation by discussing the motivations, methods, and research findings.Chapter two develops a framework that nests both symmetric and asymmetric employer learning, and derives testable hypotheses on racial statistical discrimination under different processes of employer learning. Testing the model with data from the NLSY79, we find that employers statistically discriminate against black workers on the basis of both education and race in the high school market where learning appears to be mostly asymmetric. In the college market, employers directly observe most parts of the productivity of potential employees and learn very little over time.
In chapter three, we investigate how the process of employer learning and statistical discrimination varies over time and across employers. The comparison between the NLSY79 and the NLSY97 cohorts reveals that employer learning and statistical discrimination has became stronger over the past decades. Using the NLSY97 data, we identify three employer- specific characteristics that influencing employer learning and statistical discrimination, the supervisor-worker race match, supervisor\'s age, and firm size. Black high school graduates face weaker employer learning and statistical discrimination if they choose to work for a black supervisor, work for an old supervisor, or work in a firm of small size.
In the last chapter, we are interested in the associations between verbal and quantitative skills and individual earnings as well as the employer learning process of these two specific types of skills. There exist significant differences in both the labor market rewards and employer learning process of verbal and quantitative skills between high school and college graduates. Verbal skills are more important than quantitative skills for high school graduates, whereas college-educated workers benefit greatly from having high quantitative skills but little from having high verbal skills. In addition, employers directly learn verbal skills and continuously learn quantitative skills in the high school market, but almost perfectly observe quantitative skills in the college market.
Ph. D.
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Yates, James William. "Mixing Staged Data Flow and Stream Computing Techniques in Modern Telemetry Data Acquisition/Processing Architectures." International Foundation for Telemetering, 1999. http://hdl.handle.net/10150/608707.
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International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, NevadaToday’s flight test processing systems must handle many more complex data formats than just the PCM and analog FM data streams of yesterday. Many flight test programs, and their respective test facilities, are looking to leverage their computing assets across multiple customers and programs. Typically, these complex programs require the ability to handle video, packet, and avionics bus data in real time, in addition to handling the more traditional PCM format. Current and future telemetry processing systems must have an architecture that will support the acquisition and processing of these varied data streams. This paper describes various architectural designs of both staged data flow and stream computing architectures, including current and future implementations. Processor types, bus design, and the effects of varying data types, including PCM, video, and packet telemetry, will be discussed.
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Böhnisch, Torben [Verfasser], Franc [Akademischer Betreuer] [Gutachter] Meyer, Guido [Gutachter] Clever, Thomas [Gutachter] Waitz, Ulf [Gutachter] Diederichsen, Dietmar [Gutachter] Stalke, and Konrad [Gutachter] Koszinowski. "C2-Symmetric Pyrazole-Bridged Ligands and Their Application in Asymmetric Transition-Metal Catalysis / Torben Böhnisch. Betreuer: Franc Meyer. Gutachter: Franc Meyer ; Guido Clever ; Thomas Waitz ; Ulf Diederichsen ; Dietmar Stalke ; Konrad Koszinowski." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2016. http://d-nb.info/1103233963/34.
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Santilli, Vincent. "THE EFFECTS OF POWER DISTANCE, AND GENDER ON THE USE OF NONVERBAL IMMEDIACY BEHAVIORS IN SYMMETRICAL AND ASYMMETRICAL POWER COND." Master's thesis, University of Central Florida, 2010. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3715.
Full textAbstract:
Previous cross-cultural research in nonverbal immediacy indicates that nonverbal immediacy behavior varies across cultures, and some researchers have suggested that power distance might serve as a moderating variable, however no research has systematically set out to determine whether that is the case. This study assessed the perceived use of nonverbal immediacy under symmetric and asymmetric power conditions, as well as gender, in three cultures: Brazil, Kenya, and the United States. Quantitative data was collected from 527 participants who completed a nonverbal immediacy measure and an individual power distance measure under either a symmetric or an asymmetric power condition. Results related to power distance partially supported the idea that cultural power distance may act as a moderating variable with regard to the use of nonverbal immediacy behaviors. Related to gender, results revealed that: (a) female participants perceived more nonverbal immediacy behaviors than males, (b) under symmetric power conditions females were perceived to use more nonverbal immediacy than males, and (c) under asymmetric power conditions there was no statistically significant difference between use of nonverbal immediacy behaviors between females and males. Implications of results, limitations, and suggestions for future research are presented.M.A.
Nicholson School of Communication
Sciences
Communication MA