Dissertations / Theses on the topic 'Content constraints'
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Lakay, Elthea Trevolee. "SIP-based content development for wireless mobile devices with delay constraints." Thesis, University of the Western Cape, 2006. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_9048_1182233050.
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SIP is receiving much attention these days and it seems to be the most promising candidate as a signaling protocol for the current and future IP telephony services. Realizing this, there is the obvious need to provide a certain level of quality comparable to the traditional telephone service signalling system. Thus, we identified the major costs of SIP, which were found to be delay and security. This thesis discusses the costs of SIP, the solutions for the major costs, and the development of a low cost SIP application. The literature review of the components used to develop such a service is discussed, the networks in which the SIP is used are outlined, and some SIP applications and services previously designed are discussed. A simulation environment is then designed and implemented for the instant messaging service for wireless devices. This environment simulates the average delay in LAN and WLAN in different scenarios, to analyze in which scenario the system has the lowest costs and delay constraints.
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Fragkoudi, Frantzeska. "Modelling peanuts in barred galaxies : gas flows and constraints on the dark matter content." Thesis, Aix-Marseille, 2015. http://www.theses.fr/2015AIXM4747/document.
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En explorant la dynamique des galaxies nous obtenons des renseignements concernant leurs différents composants de masse, leur formation et évolution. Dans cette thèse, j'utilise des modèles dynamiques obtenus à partir des images de galaxies observées. Je commence par l'amélioration de ces modèles en incluant la géométrie des bulbes cacahuètes (B/P), et en quantifiant leurs effets sur les modèles. Les bulbes B/P ont un effet significatif sur le potentiel, les forces, la structure orbitale et la force de la barre, et par conséquent devraient être inclus dans le but de rendre les modèles aussi précis que possible. En suite, j’emploie des modèles dynamiques avec et sans B/P pour déterminer leur effet sur les flux de gaz vers les régions centrales. Je montre que, si le modèle contient un bulbe B/P, la force de la barre est réduite et, par conséquence, le montant d'afflux du gaz conduit à des concentrations de masse réduites dans les centres des galaxies. Je me sers des modèles dynamiques pour étudier la galaxie NGC 1291. J'utilise la nature non-axisymétrique de la barre, ce qui induit des chocs dans le gaz - créant ainsi des bandes de poussière dans la barre - pour imposer des contraintes sur le ratio masse-à-lumière des disques. Les résultats soutiennent que NGC 1291 a un disque maximale et que dans les régions centrales, la matière baryonique domine la matière noire. Je mets aussi des limites sur la vitesse de rotation de la barre, montrant qu’elle tourne vite. Je démontre donc que la méthode dynamique utilisée, peut fournir des contraintes sur la distribution de la matière noire des galaxies observées, et donc aussi sur les modèles de formation et évolution des galaxiesBy exploring the dynamics of galaxies we obtain a wealth of information regarding their various mass components, their formation and evolution. In this thesis I make extensive use of dynamical models obtained directly from images of observed galaxies. I therefore start by improving these models by including the geometry of boxy/peanut (B/P) bulges, and quantifying their effects on the models. B/P bulges have a significant effect on the potential, forces, orbital structure and bar strength of the models, and as such should be included in order to make them as accurate as possible. I then employ dynamical models with and without B/P bulges to determine their effect on gas inflow to the central regions. I show that in the presence of B/P bulges the bar strength is reduced, as is the amount of gas inflow, leading to smaller mass concentrations in the centres of galaxies. Furthermore, I employ dynamical models to carry out a detailed study of the nearby galaxy NGC 1291. I use the non-axisymmetric nature of the bar, which induces shocks in the gas - thus creating dust lanes along the leading edges of the bar - to put constraints on the mass-to-light ratio of the disc. The results argue strongly that NGC 1291 has a maximal disc, i.e. that in the central regions, baryonic matter dominates over the dark matter. Furthermore I place limits on the pattern speed of the bar, showing that the bar rotates fast. I thus demonstrate that the dynamical method used can provide constraints on the dark matter distribution of observed galaxies, and therefore also on current models of galaxy formation and evolution
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Ng, Mo Ching Norma. "Commercial constraints and news content : a comparative study of quality newspapers in France and in the U.S." HKBU Institutional Repository, 2004. http://repository.hkbu.edu.hk/etd_ra/611.
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Juhász, Attila. "Diagenetic constraints on the paleohydrodynamic and thermal reconstruction of neogene sediments at the Békés Basin - Battonya high hydrocarbon province, SE Hungary /." [S.l.] : [s.n.], 1999. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.
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Weigel, Gerolf. "The soils of the Maybar/Wello and Gununo/Sidamo area : their potential and constraints for agricultural development : a case study in the Ethiopian Highlands /." [S.l.] : [s.n.], 1986. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.
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Nakata, Dorene Samantha. "Syn-eruptive degassing of a single submarine lava flow : constraints on MORB CO₂ variability, vesiculation, and eruption dynamics." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1912/3933.
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Thesis (S.M.)--Joint Program in Marine Geology and Geophysics (Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences; and the Woods Hole Oceanographic Institution), 2010.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 33-37).
Mid-ocean ridge basalts (MORBs) exhibit a wide range of CO2 concentrations, reflecting saturation to supersaturation (and rarely undersaturation) relative to their emplacement depths. In this study, we explore the mechanisms of CO2 degassing and the implications this has for estimating the advance rates and durations of seafloor eruptions. We present dissolved volatile concentrations (mainly of CO 2 and H20) and vesicle size distributions (VSDs) for a unique suite of MORB glasses collected at the East Pacific Rise, ~9° 50' N. These MORB glasses were collected at -200 m intervals along an across-axis track over a single flow pathway within the recently emplaced 2005-06 eruption boundaries; systematic sample collection provides one of the first opportunities to characterize intra-flow geochemical and physical evolution during a single eruption at a fast-spreading ridge. Compared to measurements of MORB volatiles globally, dissolved H20 concentrations are relatively uniform (0.10 - 0.16 weight percent), whereas dissolved CO2 contents exhibit a range of concentrations (154 - 278 ppm) and decrease with distance from the EPR axis (i.e., eruptive vent). Ion microprobe analysis of dissolved volatiles within the MORB glasses suggest that the magma erupted supersaturated (pressure equilibrium with 920 - 1224 mbsf) and in near-equilibrium with the melt lens of the axial magma chamber (~1250 - 1500 mbsf), and degassed to near equilibrium (299 - 447 mbsf) with seafloor depths over the length of the flow. The decrease in CO 2 concentrations spans nearly the full range of dissolved CO2 contents observed at the EPR and shows that the varying degrees of volatile saturation that have been observed in other MORB sample suites may be explained by degassing during emplacement. Vesicularity (0.1 - 1.2%) increases with decreasing dissolved CO2 concentrations. We use vesicle size distributions (VSDs)-vesicle sizes and number densities-to quantify the physical evolution of the CO2 degassing process. VSDs suggest that diffusion of CO2 into preexisting vesicles, and not nucleation of new vesicles, is the dominant mechanism of increasing CO2 in the vapor phase. We also use VSDs, along with estimates of vesicle growth rates, to constrain emplacement time of the 2005-06 eruption to <~24 hours and to resolve variations in advance rate with down flow distance.
by Dorene Samantha Nakata.
S.M.
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Kutty, Sangeetha. "Enriching XML documents clustering by using concise structure and content." Thesis, Queensland University of Technology, 2011. https://eprints.qut.edu.au/48326/1/Sangeetha_Kutty_Thesis.pdf.
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With the growing number of XML documents on theWeb it becomes essential to effectively organise these XML documents in order to retrieve useful information from them. A possible solution is to apply clustering on the XML documents to discover knowledge that promotes effective data management, information retrieval and query processing. However, many issues arise in discovering knowledge from these types of semi-structured documents due to their heterogeneity and structural irregularity. Most of the existing research on clustering techniques focuses only on one feature of the XML documents, this being either their structure or their content due to scalability and complexity problems. The knowledge gained in the form of clusters based on the structure or the content is not suitable for reallife datasets. It therefore becomes essential to include both the structure and content of XML documents in order to improve the accuracy and meaning of the clustering solution. However, the inclusion of both these kinds of information in the clustering process results in a huge overhead for the underlying clustering algorithm because of the high dimensionality of the data. The overall objective of this thesis is to address these issues by: (1) proposing methods to utilise frequent pattern mining techniques to reduce the dimension; (2) developing models to effectively combine the structure and content of XML documents; and (3) utilising the proposed models in clustering. This research first determines the structural similarity in the form of frequent subtrees and then uses these frequent subtrees to represent the constrained content of the XML documents in order to determine the content similarity. A clustering framework with two types of models, implicit and explicit, is developed. The implicit model uses a Vector Space Model (VSM) to combine the structure and the content information. The explicit model uses a higher order model, namely a 3- order Tensor Space Model (TSM), to explicitly combine the structure and the content information. This thesis also proposes a novel incremental technique to decompose largesized tensor models to utilise the decomposed solution for clustering the XML documents. The proposed framework and its components were extensively evaluated on several real-life datasets exhibiting extreme characteristics to understand the usefulness of the proposed framework in real-life situations. Additionally, this research evaluates the outcome of the clustering process on the collection selection problem in the information retrieval on the Wikipedia dataset. The experimental results demonstrate that the proposed frequent pattern mining and clustering methods outperform the related state-of-the-art approaches. In particular, the proposed framework of utilising frequent structures for constraining the content shows an improvement in accuracy over content-only and structure-only clustering results. The scalability evaluation experiments conducted on large scaled datasets clearly show the strengths of the proposed methods over state-of-the-art methods. In particular, this thesis work contributes to effectively combining the structure and the content of XML documents for clustering, in order to improve the accuracy of the clustering solution. In addition, it also contributes by addressing the research gaps in frequent pattern mining to generate efficient and concise frequent subtrees with various node relationships that could be used in clustering.
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Li, Pei. "Water contents and lithium isotope compositions of the Mesozoic-Cenozoic lithospheric mantle of eastern North China Craton : constraints from peridotite xenoliths." Thesis, Université de Lorraine, 2012. http://www.theses.fr/2012LORR0415/document.
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Pour mieux comprendre le processus géodynamique qui a permis la destruction du craton Nord Chinois (NCC), le rôle des fluides mantelliques a été examiné. Pour cela, les distributions des teneurs en eau et des compositions isotopiques du Lithium dans le manteau lithosphérique NCC ont été déterminées à partir des xénolites de péridotite entrainés par les basaltes mésozoïques et cénozoïques. Une variation temporelle des teneurs en eau est observée. Le manteau lithosphérique cénozoïque est appauvri en eau, sans doute suite à l'amincissement crustal et au réchauffement du manteau résiduel par un flux ascendant asthénosphérique. Le manteau lithosphérique mésozoïque montre des teneurs en eau intermédiaire entre les teneurs élevées du Crétacé et les teneurs basses cénozoïques, indiquant une déshydratation du manteau commençant dès le début de sa destruction. Cette déshydratation, facilitée par la destruction du manteau lithosphérique profond, permet de renforcer la rigidité de la lithosphère et lui permet de résister à la convection mantellique. Les distributions élémentaire et isotopique du Li montrent une grande hétérogénéité, aux échelles intra et inter-cristallines. Par simulation numérique, nous démontrons que deux enrichissements successifs ont affecté le manteau, un enrichissement limité (<5ppm) avec une signature pauvre en 7Li ([delta]7Li ~ -20 [pour mille]), suivi d'un enrichissement important (> 100 ppm) avec une signature riche ([delta]7Li ~ +20 [pour mille]), précédent de peu l'exhumation des xénolites. La formation des liquides métasomatiques responsables de ces enrichissements nécessite une distribution hétérogène dans le manteau NCC d'éléments recyclés lors de la subduction à l'est du NCCIn order to investigate the geodynamic cause for destruction of the North China Craton (NCC), the role of mantle fluids is examined. The aim of the PHD work is to clarify H2O contents and lithium isotopic compositions of the NCC lithospheric mantle by studying peridotite xenoliths hosted by Mesozoic-Cenozoic basalts across eastern NCC. A temporal variation of H2O content has been revealed, and it has deep implications for processes of craton destruction. The Cenozoic lithospheric mantle was featured by low H2O content, interpreted to be the relict mantle that survived the lithospheric thinning and has been dewatered by reheating from upwelling asthenospheric flow. The late-Mesozoic lithospheric mantle showed relatively high H2O content, a hydrous status intermediate between the Cretaceous hydration and the Cenozoic dryness, indicating the dehydration of the NCC mantle with time during NCC destruction. The dehydration, facilitated by thinning of weak mantle pieces at bottom, is one way by which the lithosphere strengthens itself to survive in the convecting mantle. Extreme Li and isotopic disequilibria were observed intra- and inter-mineral in the peridotites. With numerical simulations, we demonstrate two superimposed Li enrichment events occurring at the mantle: a limited Li enrichment (< 5 ppm) and large delta7Li depletion (-20~-10[per 1000]) of the mantle domain, followed by a recent and transient infiltration of high Li and delta7Li (up to +20 [per 1000]) melts/fluids. The anomalous Li isotopic compositions of mantle metasomatic agents call upon the same of their mantle sources, and we assume recycled components, both Li isotopically heavy and light, in the mantle beneath the eastern NCC
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Miozzi, Ferrini Francesca. "Experimental study of the Fe-Si-C system and application to carbon rich exoplanet." Electronic Thesis or Diss., Sorbonne université, 2019. https://accesdistant.sorbonne-universite.fr/login?url=https://theses-intra.sorbonne-universite.fr/2019SORUS241.pdf.
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Plus de 4000 exoplanètes ont été découvertes, orbitant autour d’étoiles ayant différentes compositions. Ces exoplanètes sont détectées et étudiées par observations indirectes qui, dans de nombreux cas, donnent accès aux propriétés principales des planètes: leurs masses et leurs rayons. Ces paramètres peuvent être calculés à partir d’un modèle et comparés à ceux observés. Toutefois, cela est plus difficile pour des planètes qui orbitent autour d’étoiles ayant une composition chimique différente du Soleil, par exemple enrichie en carbone, car les propriétés physiques des carbures (i.e. carbures de silicium ou de fer) sont inconnues. Dans cette étude les systèmes Si-C et Fe-Si-C ont été étudiés entre 20 et 200 GPa et 300-3000 K, en utilisant la diffraction de rayons x et l’analyse chimique des échantillons récupérés pour déterminer les propriétés physiques dans des conditions extrêmes. Dans le système Si-C les équations d’états et les modèles thermiques pour les deux phases de basse et haute pression ont été déterminés. Les résultats ont ensuite été utilisé pour calculer la relation masse-rayon de planètes synthétiques ayant un noyau de fer et un manteau de SiC. Concernant le système Fe-Si-C le diagramme de phase ternaire a été reconstruit. En faisant l’hypothèse d’une composition Fe-Si-C pour un noyau planétaire, quatre différentes séquences de cristallisation ont été démontrées, déterminant des comportements dynamiques très diffèrent. En conclusion la relation masse-rayon n’est pas suffisante pour déterminer la composition et la structure interne des exoplanètes observées mais des données relatives à la chimie du système planétaire sont requisesMore than 4000 exoplanets have been discovered, orbiting around stars with a wide variety of composition. Such planets are detected and studied through indirect methods that in many cases give access to the main properties of the planets: mass and radius. The same parameters can be calculated from a chosen model and compared to the observed ones. However it is difficult for planets orbiting around stars with compositions very different from our Sun, for example carbon enriched, as the physical properties carbides (i.e. silicon carbides and iron carbides) at extreme pressure are unknown. In this work the Si-C and Fe-Si-C systems were studied in the range between 20 and 200 GPa and 300-3000 K employing X-ray diffraction and chemical analyses on the recovered samples were used to determine the physical properties at extreme conditions. In the Si-C system the equations of state and thermal model for both the low pressure and high pressure phases were determined. The results were then used to model a mass radius plot for different archetypal planets with a Fe core and SiC mantle. Regarding the Fe-Si-C system a ternary phase diagram was reconstructed up to 200 GPa and 3000 K. Assuming Fe-Si-C as main component of planetary cores, four different crystallization paths are individuated, giving rise to way different dynamical behaviour. We conclude that using only mass radius relations is not sufficient to determine the interior composition and structure of an observed exoplanet and further data relative to the chemistry are needed, for example the composition of the host star
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Bengtsson, Daniel, and Johan Melin. "Constrained procedural floor plan generation for game environments." Thesis, Blekinge Tekniska Högskola, Institutionen för kreativa teknologier, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-13006.
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Background: Procedural content generation (PCG) has become an important subject as the demand for content in modern games has increased. Paradox Arctic is a game development studio that aims to be at the forefront of technological solutions and is therefore interested in furthering their knowledge in PCG. To this end, Paradox Arctic has expressed their interest in a collaborative effort to further explore the subject of procedural floor plan generation. Objective: The main goal of this work is to test whether a solution based on growth, subdivision or a combination thereof, can be used to procedurally generate believable and varied floor plans for game environments, while also conforming to predefined constraints. Method: A solution capable of generating floor plans with the use of growth, subdivision and a combination of both has been implemented and a survey testing the believability and variation of the generated layouts has been conducted. Results & Conclusions: While the results of the subdivision and combined solutions show that more work is necessary before the generated content can be considered believable, the growth based solution presents promising results in terms of believability when generating smaller to medium sized layouts. This believability does however come at the cost of variation.Bakgrund: Procedural content generation (PCG) har blivit ett alltmer viktigt ämne allteftersom kravet på mängden innehåll i moderna spel har ökat. Paradox Arctic är en spelutvecklingsstudio vars målsättning är att ligga i teknologins framkant och de är därför intresserade av att vidareutveckla sin kompetens inom PCG. Av denna anledning har de uttryckt intresse för ett samarbete inom området “procedurell generering av planlösningar”. Syfte: Det huvudsakliga syftet med detta arbete är att undersöka huruvida lösningar baserade på att växa ytor, fördela ytor i mindre delar eller en kombination av dessa, kan användas för att skapa trovärdiga och varierade planlösningar för spelmiljöer, utan att bryta förutbestämda krav. Metod: En lösning som procedurellt genererar planlösningar genom att växa och/eller fördela dem har implementerats och en undersökning, med syftet att utvärdera trovärdigheten och variationen i de genererade planlösningarna, har utförts. Resultat & Slutsatser: Lösningen som baseras på fördelning av ytor och den kombinerade lösningen, visades av resultaten kräva ytterliggare arbete för att anses generera trovärdiga resultat. Lösningen som baseras på att växa ytor däremot, visade positiva trovärdighetsresultat när små och medelstora planlösningar genererades. Detta goda resultat uppstod dock på bekostnaden av variation mellan de genererade planlösningarna.
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Rosales, Gallegos Carlos. "Grasp plannind under task-specific contact constraints." Doctoral thesis, Universitat Politècnica de Catalunya, 2013. http://hdl.handle.net/10803/116770.
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Several aspects have to be addressed before realizing the dream of a robotic hand-arm system with human-like capabilities, ranging from the consolidation of a proper mechatronic design, to the development of precise, lightweight sensors and actuators, to the efficient planning and control of the articular forces and motions required for interaction with the environment. This thesis provides solution algorithms for a main problem within the latter aspect, known as the {\em grasp planning} problem: Given a robotic system formed by a multifinger hand attached to an arm, and an object to be grasped, both with a known geometry and location in 3-space, determine how the hand-arm system should be moved without colliding with itself or with the environment, in order to firmly grasp the object in a suitable way.
Central to our algorithms is the explicit consideration of a given set of hand-object contact constraints to be satisfied in the final grasp configuration, imposed by the particular manipulation task to be performed with the object. This is a distinguishing feature from other grasp planning algorithms given in the literature, where a means of ensuring precise hand-object contact locations in the resulting grasp is usually not provided. These conventional algorithms are fast, and nicely suited for planning grasps for pick-an-place operations with the object, but not for planning grasps required for a specific manipulation of the object, like those necessary for holding a pen, a pair of scissors, or a jeweler's screwdriver, for instance, when writing, cutting a paper, or turning a screw, respectively. To be able to generate such highly-selective grasps, we assume that a number of surface regions on the hand are to be placed in contact with a number of corresponding regions on the object, and enforce the fulfilment of such constraints on the obtained solutions from the very beginning, in addition to the usual constraints of grasp restrainability, manipulability and collision avoidance.
The proposed algorithms can be applied to robotic hands of arbitrary structure, possibly considering compliance in the joints and the contacts if desired, and they can accommodate general patch-patch contact constraints, instead of more restrictive contact types occasionally considered in the literature. It is worth noting, also, that while common force-closure or manipulability indices are used to asses the quality of grasps, no particular assumption is made on the mathematical properties of the quality index to be used, so that any quality criterion can be accommodated in principle. The algorithms have been tested and validated on numerous situations involving real mechanical hands and typical objects, and find applications in classical or emerging contexts like service robotics, telemedicine, space exploration, prosthetics, manipulation in hazardous environments, or human-robot interaction in general.
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Movahhed, Abdolmohammad. "Context and constraints in Stanley Fish's reader-response theory." Thesis, University of Strathclyde, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.510849.
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Snead, Kathleen Benton. "Contextual Constraints: An Examination of Implicit Followership Theories." Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/41437.
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This study was designed to assess follower prototypes as dynamic structures. Connectionist theory is a good framework to understand the process by which followership perceptions are altered by contextual factors. Organizational culture, change in immediate leader and follower prototypes were measured in an applied setting across time to assess the dynamism of the cognitive networks of implicit followership theories. Change in culture and immediate leader was measured at three time points, across six months, during the acquisition of one organization by a second. Change scores were created by computing difference scores from surveys completed at the first time point to the second time point, three months later, to the third and final time point, three months later. There were no significant effects of change in culture on reported follower networks. There was, however, a significant effect of leader change at time points two and three when regressed on individualâ s follower networks. The overall findings of this study suggest that IFTâ s like leadership prototypes remain fairly stable across time (Epitropaki, 2004), but are subject to organizational change.Master of Science
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He, Jun. "Constraints for Membership in Formal Languages under Systematic Search and Stochastic Local Search." Doctoral thesis, Uppsala universitet, Avdelningen för datalogi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-196347.
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This thesis focuses on constraints for membership in formal languages under both the systematic search and stochastic local search approaches to constraint programming (CP). Such constraints are very useful in CP for the following three reasons: They provide a powerful tool for user-level extensibility of CP languages. They are very useful for modelling complex work shift regulation constraints, which exist in many shift scheduling problems. In the analysis, testing, and verification of string-manipulating programs, string constraints often arise. We show in this thesis that CP solvers with constraints for membership in formal languages are much more suitable than existing solvers used in tools that have to solve string constraints. In the stochastic local search approach to CP, we make the following two contributions: We introduce a stochastic method of maintaining violations for the regular constraint and extend our method to the automaton constraint with counters. To improve the usage of constraints for which there exists no known constant-time algorithm for neighbour evaluation, we introduce a framework of using solution neighbourhoods, and give an efficient algorithm of constructing a solution neighbourhood for the regular constraint. In the systematic search approach to CP, we make the following two contributions: We show that there may be unwanted consequences when using a propagator that may underestimate a cost of a soft constraint, as the propagator may guide the search to incorrect (non-optimum) solutions to an over-constrained problem. We introduce and compare several propagators that compute correctly the cost of the edit-distance based soft-regular constraint. We show that the context-free grammar constraint is useful and introduce an improved propagator for it.
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Nehra, Ram S. "Modeling time space prism constraints in a developing country context." [Tampa, Fla.] : University of South Florida, 2004. http://purl.fcla.edu/fcla/etd/SFE0000299.
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Bübl, Felix. "Tracing crosscutting requirements for component based systems via context based constraints." [S.l.] : [s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=976731169.
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May, Richard John. "Perceptual content loss in bit rate constrained IFS encoded speech." Thesis, University of Portsmouth, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.396323.
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Hollis, Geoff R. "The Role of Task Constraints in Ambiguity Resolution." University of Cincinnati / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1282168797.
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Andereck, Michael. "Procedural Terrain Generation Based on Constraint Paths." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1388357258.
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Karatas, Ahmet Serkan. "Analysis Of Extended Feature Models With Constraint Programming." Phd thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/3/12612082/index.pdf.
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In this dissertation we lay the groundwork of automated analysis of extended feature models with constraint programming. Among different proposals, feature modeling has proven to be very effective for modeling and managing variability in Software Product Lines. However, industrial experiences showed that feature models often grow too large with hundreds of features and complex cross-tree relationships, which necessitates automated analysis support. To address this issue we present a mapping from extended feature models, which may include complex feature-feature, feature-attribute and attribute-attribute cross-tree relationships as well as global constraints, to constraint logic programming over finite domains. Then, we discuss the effects of including complex feature attribute relationships on various analysis operations defined on the feature models. As new types of variability emerge due to the inclusion of feature attributes in cross-tree relationships, we discuss the necessity of reformulation of some of the analysis operations and suggest a revised understanding for some other. We also propose new analysis operations arising due to the nature of the new variability introduced. Then we propose a transformation from extended feature models to basic/cardinality-based feature models that may be applied under certain circumstances and enables using SAT or BDD solvers in automated analysis of extended feature models. Finally, we discuss the role of the context information in feature modeling, and propose to use context information in staged configuration of feature-models.
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HOLANDA, AUREA SILVA DE. "ANALYSIS OF THE EQUILIBRIUM AND STABILITY OF PLATES WITH CONTACT CONSTRAINTS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2000. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=2002@1.
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CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICONeste trabalho é desenvolvida uma metodologia baseada no Método dos Elementos Finitos para estudar o equilíbrio e a estabilidade de placas apoiadas em fundações elásticas. A formulação utilizada para a análise de placas é válida para a análise linear e não-linear de placas isotrópicas ou ortotrópicas, perfeitas ou inicialmente imperfeitas. Esta formulação é baseada nas teorias de placas de Mindlin e von Kármán e na teoria de cascas abatidas proposta por Marguerre. As placas podem estar apoiadas em fundações lineares ou não-lineares, que são modeladas utilizando elementos finitos isoparamétricos. A fundação não-linear contém termos cúbicos e quadráticos, de modo a permitir uma representação mais realista do seu comportamento. Na obtenção dos caminhos não-lineares de equilíbrio das estruturas, diferentes métodos incrementais-iterativos são utilizados. Com o objetivo de considerar o problema de contato unilateral, duas formulações que utilizam técnicas de Programação Matemática são implementadas, sendo uma para a análise linear e outra para a análise não-linear. Além dessas formulações, o problema de contato unilateral pode ser tratado através do uso de um modelo constitutivo de fundação não resistente à tração também implementado neste trabalho. Exemplos de equilíbrio e de estabilidade são apresentados e, quando possível, os resultados são comparados com os existentes na literatura. Através destes exemplos, estuda-se a influência da não-linearidade da placa e da fundação, das imperfeições geométricas iniciais e do tipo de contato (unilateral ou bilateral) na capacidade de carga e estabilidade da placa. Também é discutida a influência do uso de diferentes malhas de elementos finitos nestes resultados, bem como a eficiência computacional das metodologias utilizadas para lidar com o contato unilateral.
In this work, a finite element formulation to study the equilibrium and the stability of plates on elastic foundations is developed. This formulation can be used for linear and nonlinear analyses of isotropic or orthotropic, perfect or initially imperfect plates. It is based on Mindlin`s and von Kármán`s plate theories and on the shallow shell theory proposed by Marguerre.The plates can be on linear or non-linear foundations modeled using isoparametric finite elements. The non-linear foundation contains cubic and quadratic terms to allow a more realistic representation of its behavior. In order to obtain the equilibrium path of the structure, different incremental-iterative methods are employed.Two different strategies are implemented to solve the unilateral contact problem. In the first one, two formulations that use optimization techniques are developed, one for the linear analysis and the other one for non-linear analysis. The second strategy modifies the constitutive relation of the foundation in order to simulate its tensionless behavior.Equilibrium and stability examples are presented and, whenever possible, the results are compared with the ones found in the literature. In these examples, the influence of the non-linearities of the plate and the foundation, of initial geometric imperfections, and of the type of contact (unilateral or bilateral) on the load capacity and stability of the plate is studied. The influence of different finite element meshes on the results and the computational efficiency of the methodologies used to solve the unilateral contact problem are also discussed.
En este trabajo se desarrolla una metodología basada en el Método de los Elementos Finitos para estudiar el equilibrio y la estabilidad de placas apoyadas en fundaciones elásticas. La formulación utilizada para el análisis de placas es válida para el análisis lineal y no lineal de placas isotrópicas o ortotrópicas, perhechas o inicialmente imperhechas. Esta formulación tiene como base las teorías de placas de Mindlin y von Kármán y en la teoría propuesta por Marguerre. Las placas pueden estar apoyadas en fundaciones lineales o no lineales, que son modeladas utilizando elementos finitos isoparamétricos. La fundación no lineal contiene términos cúbicos y cuadráticos, de modo que permita una representación más realista del su comportamiento. En la obtención de los caminos no lineales de equilibrio de las extructuras, se utilizaron diferentes métodos incrementales iterativos. Con el objetivo de considerar el problema de contacto unilateral, se implementan dos formulaciones que utilizan técnicas de Programación Matemática, una para el análisis lineal y otra para el análisis no lineal. Además de esas formulaciones, el problema de contacto unilateral puede ser tratado a través del uso de un modelo constitutivo de fundación no resistente a la tracción, que también es implementado en este trabajo. Se presentan ejemplos de equilíbrio y de estabilidad y, cuando posible, se comparan los resultados con los existentes en la literatura. A través de estos ejemplos, se estudia la influencia de la no linealidad de la placa y de la fundación, de las imperfecciones geométricas iniciales y del tipo de contacto (unilateral o bilateral) en la capacidad de carga y la estabilidad de la placa. También se discute la influencia del uso de diferentes mallas de elementos finitos em estos resultados, así como la eficiencia computacional de las metodologías utilizadas para tratar el contacto unilateral.
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Russell, Scott Raymond. "Interacting constraints shape emergent decision-making of referees." Thesis, Queensland University of Technology, 2013. https://eprints.qut.edu.au/61021/1/Scott%20Russell%20Thesis.pdf.
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How and why football referees made decisions was investigated. A constructivist grounded theory methodology was undertaken to tap into the experiential knowledge of referees. The participant cohort comprised 7 A-League referees (aged 23 to 35) and 8 local Brisbane league referees (aged 20 to 50), spanning the lowest to highest levels of competition in men’s football in Australia. Results found that referees used ‘four pillars’ to underpin their judgments, these were conceptual notions of: safety, fairness, accuracy and entertainment. A fifth pillar ‘consistency’ referred to the referee’s ‘contextual sensitivity’. Results were explained using an ecological dynamics framework that emphasises the individual-environment scale of analysis. It was concluded that interacting constraints shape emergent decision-making in referees which are nested in task goals.
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Ditzel, Kropiwiec Cássio. "Framework for distributed firewall administration in a multi-constraint security policies context." Paris 6, 2009. http://www.theses.fr/2009PA066162.
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Ce travail présente une nouvelle approche pour représenter ces règles de sécurité d’un réseau global. Le framework proposé définit un langage de règles de haut niveau, qui permet les spécifications de ces règles selon des modèles de sécurité obligatoires, discrétionnaires et de propriétés. Ce Framework est capable de gérer simultanément les trois dimensions et décrit de manière cohérente les autorisations résultantes sous la forme d’une représentation abstraite, indépendante de la façon dont elles seront mises en place, et sans violer l’objectif de sécurité globale. Le Framework inclue aussi un mécanisme responsable pour la traduction de la représentation abstraite des autorisations en scripts/règles de configuration de bas-niveau pour des pare-feu de différents modèles et fabricants, permettant son utilisation pour la configuration de réseaux hétérogènes. Chaque dimension peut être définie par des personnes ayant différents rôles, permettant une coopération pour la définition d’une politique globale. Le Framework est formalisé avec Z afin de démontrer sa complétude et sa rigueur. Une étude d’extensibilité est présentée pour expliquer le comportement du Framework pour des réseaux plus larges.
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Ernst, Antonia 1976. "Project and procurement method selection in the context of portfolio consideration and financial constraints." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/80974.
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Kalpundi, Ganesh R. "Nonlinear mixed finite element analysis for contact problems by a penalty constraint technique." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-06302009-040252/.
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au, A. Stebbins@murdoch edu, and Andrew Stebbins. "The Chinese Civilizing Process: Eliasian Thought as an Effective Analytical Tool for the Chinese Cultural Context." Murdoch University, 2009. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20100211.123651.
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This thesis is an effort to apply Eliass thinking on social development to the Chinese social situation. At first glance his account of the civilizing process would appear incompatible with this context, in that, after state formation with the Qin and Han dynasties beginning in 221 BC, Chinese civilization remained both stable and highly traditional for well over two millennia. It is argued, however, that closer scrutiny reveals a process that was merely interrupted for a considerable period. The traditional system relied upon a symbiotic relationship between local society and the centre whereby the centre remained relatively small and aloof, not interfering with local social relations, as long as local society provided the required taxes and labour. In this situation the state had the monopolies of both violence and taxation that Elias would look for, but left local society to its own devices primarily because it was already pacified. This self-reinforcing system was enshrined and codified in the Confucian cannon over the course of centuries from the Han dynasty.
Central control of the distribution of resources was eventually required to re-start the Chinese civilizing process, for this was the mechanism through which the local social structure would finally be altered. This only happened within the past century as the Chinese people struggled to grapple with their own backwardness in the face of incessant Western and Japanese incursions. At this point the old system was toppled and replaced by progressively more aggressive central governments who saw as their most important task the destruction of the traditional social order in the interest of modernization. As the Chinese state consciously and forcibly took control of the distribution of resources at all levels of society, traditional social relations were stretched and warped, and the Chinese civilizing process re-commenced its long-stalled march toward modernization. This has been evidenced both by the dramatic growth in mobility and the rapidly extending chains of interdependence in the form of guanxi connections primarily during the Post-Opening period after 1978.
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Erickson, Darren Andrew. "Contact stiffness and damping estimation for constrained robotic systems." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/mq53042.pdf.
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Rodrigues, Tabajara Krausburg. "Constrained coalition formation among heterogeneous agents for the multi-agent programming contest." Pontif?cia Universidade Cat?lica do Rio Grande do Sul, 2018. http://tede2.pucrs.br/tede2/handle/tede/8102.
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Esta disserta??o apresenta um estudo sobre forma??o de coaliz?es entre agentes heterog?neos para a competi??o de programa??o multiagente de 2017. Foi investigado e aplicado a forma??o de estruturas de coaliz?es entre agentes para resolver problemas log?sticos simulados sobre o mapa de uma cidade real. A fim de atingir o objetivo deste trabalho, foram integrados algoritmos formadores de coaliz?es na plataforma JaCaMo por meio de um artefato CArtAgO chamado CFArtefact. Foi utilizada a implementa??o provida pelo time SMART-JaCaMo (time participante da competi??o multiagente), para experimentar a forma??o de coaliz?es na competi??o. Tr?s abordagens foram avaliadas no dom?nio da competi??o em diferentes configura??es. A primeira abordagem utiliza somente aloca??o de tarefas para resolver o problema. A segunda e a terceira abordagem utilizam a t?cnica de forma??o de coaliz?es anteriormente ? aloca??o de tarefas; dentre estas abordagens, uma utiliza um algor?timo ?timo para resolver o problema e a outra um heur?stico. As an?lises dos experimentos realizados mostram que algor?timos formadores de coaliz?es podem melhorar a performance do time participante da competi??o quando a taxa de trabalhos gerados pelo simulador ? baixa. Entretanto, conforme a taxa de trabalhos aumenta, a abordagem que realiza somente aloca??o de tarefas obt?m um desempenho melhor quando comparada as demais. Mesmo a abordagem heur?stica tem desempenho pr?ximo ? abordagem ?tima para coaliz?es. Desta forma, ? poss?vel concluir que forma??o de coaliz?es possui grande valia para balancear os agentes para um conjunto de trabalhos que precisa ser completado.
This work focuses on coalition formation among heterogeneous agents for the 2017 multiagent programming contest. An agent is a computer system that is capable of independent action to achieve its goals. In order to increase the effectiveness of the agents, we can organise them into coalitions, in which the agents collaborate with each other to achieve individual or common goals. We investigate and apply coalition structure generation (the first activity of the coalition formation process) in simulated scenarios, specifically the 2017 contest scenario, where the agents forming a competing team cooperate to solve logistic problems simulated on the map of a real city. In order to achieve our goal, we integrate coalition formation algorithms into the JaCaMo platform by means of a CArtAgO artefact, named CFArtefact. We use the implementation of the SMART JaCaMo team for experimenting with the coalition formation approach in the contest scenario. We experiment on three approaches in the contest domain with different configurations. In the first, we use only a taskallocation mechanism, while the other approaches use an optimal coalition formation algorithm and a heuristic coalition formation algorithm. We conducted several experiments to compare the advantages of each approach. Our results show that coalition formation algorithms can improve the performance of a participating team when dealing with low job rates (i.e., how quickly new jobs are created by the simulation). However, as we increase the job rate, the approach using only task allocation has better performance. Even a heuristic coalition formation approach has close performance to the optimal one in that case. Coalition formation can play an important role when we aim to balance each group of agents to accomplish some particular goal given a larger team of cooperating agents.
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Rivière, Laura. "Etude de l'importance relative des contraintes linguistiques et extralinguistiques conduisant à la compréhension de l'ironie." Electronic Thesis or Diss., Aix-Marseille, 2019. http://www.theses.fr/2019AIXM0284.
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Ce travail de thèse a eu pour vocation, en utilisant le cadre du modèle de Satisfaction de Contraintes, de déterminer, pour la première fois en français, le rôle joué par plusieurs types de contraintes (i.e., pragmatiques, linguistiques et socioculturelles) dans la compréhension des critiques et des compliments ironiques. Suite à une première étude dans laquelle nous avons utilisé une tâche auditive, nos résultats ont mis en évidence que l’incongruité entre le contexte et l’énoncé était un indice plus fort que la prosodie lors de la compréhension de critiques ironiques. En effet, nous avons montré que si tous les participants, lors de l’interprétation, s’appuyaient sur les informations contextuelles, seuls certains participants utilisaient également les indices prosodiques. Les résultats des deux études suivantes, composées de tâches écrites, ont confirmé le rôle majeur des contraintes pragmatiques (i.e., allusion à une attente déçue, tension négative et présence d’une victime) dans la compréhension de l’ironie, et notamment dans la compréhension des critiques ironiques. Nos résultats ont également mis en évidence la contribution, bien qu’à un niveau inférieur à celle des contraintes pragmatiques, de contraintes socioculturelles des participants dans la compréhension de l’ironie. Ils ont aussi confirmé l’asymétrie de l’ironie et montré que les contraintes pragmatiques contribuant à la compréhension des compliments ironiques seraient différentes de celles contribuant à la compréhension des critiques ironiquesThe objective of this thesis was, using the framework of the Constraints Satisfaction model, to determine, for the first time in French, the role played by several types of constraints (i.e., pragmatic, linguistic and sociocultural) in the understanding of ironic criticisms and ironic praises.The results of a first experiment, in which we used a listening task, showed that the incongruity between the context and the utterance was a stronger cue than prosody in the understanding of ironic critics. Indeed, we showed that while all participants, in their interpretations, relied on contextual information, only some participants also used prosodic cues. The results of the two subsequent experiments, consisting of written tasks, confirmed the main role played by pragmatic constraints in irony understanding, and particularly in understanding of ironic criticisms. Our results also highlighted the contribution, while at a lower level than pragmatic constraints, of sociocultural constraints of the participants in the irony understanding. Our results also confirmed the asymmetry of irony and showed that the pragmatic constraints contributing to the understanding of ironic praises would be different from those contributing to the understanding of ironic criticism
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Hetet, John Stephen Tawhana. "A literary underground in Restoration England : printers and dissenters in the context of constraints, 1660-1689." Thesis, University of Cambridge, 1987. https://www.repository.cam.ac.uk/handle/1810/250909.
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Nilan, Michael Sanford. "Structural constraints and situational information seeking : a test of two predictors in a sense-making context /." Thesis, Connect to this title online; UW restricted, 1985. http://hdl.handle.net/1773/6185.
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Woerner, Kyle. "Multi-contact protocol-constrained collision avoidance for autonomous marine vehicles." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/104118.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2016.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 [294]-[301]).
The field of autonomous collision avoidance has continued to advance in many areas including sensory and perception, navigation, payload integration, and collision avoidance. The advances in collision avoidance, however, have largely focused on iterative changes to the velocity obstacle - an algorithm that inherently loses important collision avoidance information key to replicating a human-like decision space. This thesis examines algorithms that generalize the traditional velocity obstacle into a multi-threshold based approach that more realistically represent and evaluate human ship driving practices. Novel protocol-constrained collision avoidance evaluation algorithms are proposed including the ability to perform both on-line and post-mission analysis of both robots and humans. These algorithms become especially important when considering complex missions of competing objectives in a contact-dense, protocol-constrained collision avoidance environment. Introduction of competing performance metrics consistent with human ship driving practices allows autonomous collision avoidance algorithm designers to consider previously unexplored tradespaces. On-water results of up to five simultaneously interacting autonomous vessels validate the collision avoidance algorithms using four key areas of evaluation: spatial efficiency, temporal efficiency, protocol compliance, and safety. Testing of 10 complex scenarios totaled over 6,150 vehicle-pair on-water encounters. Human-robot field experimentation demonstrated autonomous collision avoidance performance under conflicting protocol requirements of COLREGS while interacting with human-driven vessels. An autonomous collision avoidance "road test" framework is proposed to incorporate testing of arbitrary collision avoidance algorithms both in the field and in simulation.
by Kyle Woerner.
Ph. D.
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Maung, David. "Tile-based Method for Procedural Content Generation." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1461077485.
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Lane, Murray C. "The development of a carrying capacity assessment model for the Australian socio-environmental context." Thesis, Queensland University of Technology, 2014. https://eprints.qut.edu.au/67485/1/Murray_Lane_Thesis.pdf.
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A key aim of this research was to highlight how society's understanding of constraints to the productive capacity of its resource base is vital to its long-term survival. This was achieved through the development of an online model, the Carrying Capacity Dashboard. The Dashboard was developed to estimate how much land Australian populations require for the production of their food, textiles, timber and liquid fuel. Findings reveal that Australia's estimated carrying capacity is currently over 40 million people but longer-term and more regional analyses suggest a much smaller number. Carrying capacity assessment also indicates that optimal resource security is to be found in balancing both small and large-scale self-sufficiency.
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Rubin, Ori. "Contact between parents and adult children: The role of time constraints, commuting and automobility." Elsevier, 2015. https://publish.fid-move.qucosa.de/id/qucosa%3A72786.
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Recent developments suggest that the need for contact between parents and adult children is expected to grow, while paid labour is re-organized to include more flexible work schedules and locations. In parallel we view a pressure to increase sustainable mobility through reducing car driving. Against this background, this paper addresses the question: to what extent the frequency of contact between parents and their adult children living out of home is associated with time allocated to work, including commuting time, and with automobility? Face-to-face and telecommunication based contact is considered. Regression analysis of survey data collected in the Netherlands was performed and results suggest that face-to-face contact was significantly associated with work and commute duration, car ownership, car commuting and distance. Telecommunication based contact was mainly associated with work duration, degree of urbanization and distance. Automobility seemed to be more important for women than for men. The policy implication is a potential trade-off between policies that aim at strengthening sustainable mobility behaviour and policies that lead to an increase in the reliance on informal care.
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Asuquo, Philip Michael. "A decentralised and context-aware trust management scheme for resource-constrained emergency communications." Thesis, University of Surrey, 2018. http://epubs.surrey.ac.uk/846412/.
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Delay Tolerant Network (DTN) provides connectivity where there is uncertainty in end-to-end connectivity. In DTN, nodes exchange bu�ered messages upon an encounter. In disaster operations where the telecommunication and power infrastructures are completely broken down or destroyed, DTN can be used to support emergency communication till these infrastructures are restored. Security in DTN remains a major challenge because of its network characteristics such as frequent disruptions, dynamic topology, limited and constrained resources. One of the major threats in DTN is Denial of Service (DoS) attacks. This attack mainly comes from intermediary nodes that drop or fl ood packets in the network which often results in the degradation of the network performance. This thesis proposes strategies for mitigating routing misbehaviour in emergency communications using DTN. This thesis proposes three innovative contributions as follows. A Collaborative Content-aware Trust Management Scheme (CCTMS) is proposed for secure routing optimisation. CCTMS incorporates structural and content similarities into the routing decision process. A trust model is developed based on direct and indirect interactions between nodes using Beta distribution model, which is used to evaluate the forwarding behaviour of encountered nodes. To optimise the routing decision, the recurrence in mobility pattern of the nodes are also exploited to form transitive similarity. The logical properties of the contents generated by the mobile nodes are also exploited to form content similarity. However, since CCTMS still incurs a high overhead and signi�cant delay, a Distributed Trust Management Scheme (DTMS) is proposed. Energy trust is integrated into the direct trust computation model as a trust metric and inter-contact graph is introduced for the computation of transitive similarity. In DTMS, the inter-contact graph is formed by the encounter between two nodes where each vertex represents an encounter between two nodes. The novelty of the inter-contact graph is the capturing of the latency distributions for each encounter between nodes. Finally, the limitation in resource constrained networks is taken into consideration and energy is identi�ed as a vital resource to ensure availability of communication in a resource constrained networks. An Energy-e�cient Semi-distributed Trust Management Scheme (ESTMS) is proposed for resource constrained emergency response networks. ESTMS assumes that trusted entities are available at each emergency response centre and are responsible for computing and �ltering recommendations. Although ESTMS increases the delivery ratio and significantly reduces the overhead ratio, it has a higher delay when compared to CCTMS and DTMS. Extensive simulations and validations show that the proposed schemes outperform existing routing and trust management protocols in the presence of malicious nodes and are resilient to trust related attacks.
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Kourouni, Kyriaki. "Translating under time constraints in an undergraduate context: a study of students' products, processes and learning styles." Doctoral thesis, Universitat Rovira i Virgili, 2012. http://hdl.handle.net/10803/84035.
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El presente estudio analiza de forma empírica si los estilos de aprendizaje se correlacionan significativamente con la calidad de traducción, cuando la tarea de traducción se desarrolla bajo restricciones de tiempo cada vez mayores. Además, el estudio vincula la práctica pedagógica con la realidad profesional, a la vez que potencia las sinergias entre dicha práctica pedagógica y la investigación empírica en el campo de la traducción. El estudio se construye gradualmente sobre el análisis de los patrones de rendimiento basado en el producto y los patrones de rendimiento basado en el proceso resultantes y luego destaca los vínculos pertinentes de la variable personal de estilos de aprendizaje. Todo ello sobre la base de los datos obtenidos sobre un total de 84 estudiantes universitarios de traducción de la Facultad de filología inglesa de la Universidad Aristóteles de Tesalónica en Grecia. Los resultados apuntan a un estilo de aprendizaje que se correlaciona significativamente con la calidad de la traducción cuando se trabaja con plazos de entrega relativamente más amplios y otro distinto cuando se aumentan las restricciones de tiempo. La evidencia empírica sugiere que los participantes experimentan un estado cognitivo de "shock" cuando sufren restricciones de tiempo cada vez mayores. Las conclusiones parecen indicar que es aconsejable favorecer un ambiente de aprendizaje que tenga en cuenta los diferentes estilos de aprendizaje de los estudiantes.The present study examines empirically whether learning styles significantly correlate with translation quality when the translation task takes place under increasing time constraints. It strives to link pedagogical practice with professional reality, while promoting synergies between pedagogical practice and empirical translation research. The study gradually builds on the analysis of emerging product- and process-based performance patterns and then highlights pertinent links with the personal variable of learning styles, on the basis of data collected from a total of 84 undergraduates studying translation at the School of English, Aristotle University of Thessaloniki, Greece. Results point to a learning style that correlates significantly with translation quality when working under a relatively relaxed deadline, and to a different one when time constraints increase. Empirical evidence also suggests that participants undergo a state of cognitive “shock” when under increasing time constraints. The conclusions seem to indicate it is worthwhile favoring a learning environment which will take into account students’ different learning styles.
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CHEN, JOHAN. "Rationalisation within a healthcare context: Application of the concept Theory of Constraints within a minor healthcare department." Thesis, KTH, Industriell Management, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-199205.
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The demand for healthcare services is currently growing worldwide with an ever increasing pace.Healthcare institutions need to adapt to the changing demographics in order to satisfy the demand. Meanwhile, many hospitals and care units have limited economic means to find appropriate solutions. A concept from the manufacturing industry that is considered to fulfill these criteria’s is called Theory of Constraints (ToC). This concept is focusing on streamlining processes by coordinating the activities and ensuring an efficient stream the production flow. This study has investigated the ability of the concept to support medical and administration staff in the department’s overall objective to decrease overall lead time.The investigation has been realized by conducting a case study at one of the largest emergency hospitals in Stockholm, Sweden. The hospital is one of the leading hospitals within Swedish medicine and receives and treats over 300000 patients annually. The case design consisted of three methods all linked to qualitative data collection, the three methods consisted of interviews, observations and shadowing.The results suggest that the application of ToC revealed little resistance to change among the participants. The concept was able to identify and resolve minor constraints in the case setting; the department of obstetrics and gynecology and also display promising characteristics in terms of solving more complex and intricate constraints. ToC as a concept were able to identify constraints in a healthcare department with a simple yet apparent cause and effect linkage. Finally, the findings indicate that ToC complements the concept of working with Continuous Improvements (CI) within the healthcare.The conclusions from this study have implications both in a theoretical perspective and a practical perspective. The findings provide additional empirical data to a field that is currently dominated by theories. In a practical aspect, the results of this study provides hospitals insights of ToC, a potentially valuable tool to improve efficiency and decrease lead times while working long-term towards an approach with CI.Det nuvarande behovet för sjukvård ökar med en allt snabbare takt världen över. Sjukhus och andravårdinstitutioner behöver anpassa sig och göra förändringar för att hantera de demografiska förändringar som sker. Samtidigt så har många sjukhus och vårdcentraler mycket begränsade resurser för att hitta lämpliga lösningar. Ett koncept från tillverkningsindustrin som betraktas som en lämplig lösning för denna situation är ett koncept som heter Theory of Constraints (ToC). Detta koncept fokuserar på att effektivisera processer genom att koordinera de aktiviteter som ingår i en process för att i sin tur säkerställa ett effektivt produktionsflöde. Denna studie har undersökt detta koncepts möjligheter att stödja medicinsk och administrativ personal i arbetet med att försöka minska ledtider i en vårdmiljö.Utredningen har genomförts praktiskt genom en fältstudie på ett av Stockholms största sjukhus. Sjukhuset är ett av de ledande inom svensk medicin och tar emot och behandlar uppemot 300 000 patienter årligen. Fältstudiens utformning bygger på tre metoder, intervjuer, skuggningar och observationer vilket alla är sammankopplade med kvalitativ datainsamling.Resultaten indikerar att tillämpandet av konceptet ToC har påvisat litet förändringsmotstånd av de som har deltagit i förändringsarbetet samt att konceptet har haft förmågan att identifiera och lösa mindre restriktioner inom sjukhusavdelningen för Obstetrik och Gynekologi. Detta har i huvudsak gjorts genom att kartlägga olika aktiviteter med en tydlig orsak och verkan samband. Utöver detta så har konceptet initialt påvisat intressanta framsteg för att eventuellt lösa mer komplexa restriktioner som begränsar produktionsflödet i en sjukhusmiljö. Vidare så framgår det att konceptet ToC i viss utsträckning kompletterar filosofin att arbeta med kontinuerliga förbättringar (Continuous Improvements/CI).Slutsatserna för denna studie har implikationer för både ett teoretiskt och praktiskt perspektiv. Utifrån ett teoretiskt perspektiv, så förser resultaten från studien med ytterligare empiriska data i ett område som för närvarande är uppbyggt av teori och litteratur. Utifrån en praktisk synvinkel ger resultaten för denna studie sjukhus och vårdinstitutioner värdefulla insikter om konceptet ToC, ett potentiellt värdefullt verktyg för att förbättra effektiviteten och minska ledtider samtidigt som det stödjer ett långsiktigt arbete med kontinuerliga förbättringar.
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Thapa, Nirmal. "CONTEXT AWARE PRIVACY PRESERVING CLUSTERING AND CLASSIFICATION." UKnowledge, 2013. http://uknowledge.uky.edu/cs_etds/15.
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Data are valuable assets to any organizations or individuals. Data are sources of useful information which is a big part of decision making. All sectors have potential to benefit from having information. Commerce, health, and research are some of the fields that have benefited from data. On the other hand, the availability of the data makes it easy for anyone to exploit the data, which in many cases are private confidential data. It is necessary to preserve the confidentiality of the data. We study two categories of privacy: Data Value Hiding and Data Pattern Hiding. Privacy is a huge concern but equally important is the concern of data utility. Data should avoid privacy breach yet be usable. Although these two objectives are contradictory and achieving both at the same time is challenging, having knowledge of the purpose and the manner in which it will be utilized helps. In this research, we focus on some particular situations for clustering and classification problems and strive to balance the utility and privacy of the data.
In the first part of this dissertation, we propose Nonnegative Matrix Factorization (NMF) based techniques that accommodate constraints defined explicitly into the update rules. These constraints determine how the factorization takes place leading to the favorable results. These methods are designed to make alterations on the matrices such that user-specified cluster properties are introduced. These methods can be used to preserve data value as well as data pattern. As NMF and K-means are proven to be equivalent, NMF is an ideal choice for pattern hiding for clustering problems. In addition to the NMF based methods, we propose methods that take into account the data structures and the attribute properties for the classification problems. We separate the work into two different parts: linear classifiers and nonlinear classifiers. We propose two different solutions based on the classifiers. We study the effect of distortion on the utility of data.
We propose three distortion measurement metrics which demonstrate better characteristics than the traditional metrics. The effectiveness of the measures is examined on different benchmark datasets. The result shows that the methods have the desirable properties such as invariance to translation, rotation, and scaling.
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Gao, Sijia. "Roadmap enhanced improvement to the VSIMM tracker via a constrained stochastic context free grammar." Thesis, University of British Columbia, 2017. http://hdl.handle.net/2429/61305.
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In this thesis, we aim to improve the tracking accuracy for targets that are moving confined to a roadmap given target observations. We build a 3-level model for this roadmap constrained target tracking problem. At the first level, the roadmap is formulated as a directed, weighted graph; at the second level, the target's trajectory is characterized via an ordered sequence of intersections it traverses. The target's roadmap constrained trajectory exploits moving directions and road or intersection names and is modeled via a CSCFG (constrained stochastic context free grammar). CSCFG arises from language processing models and is more general than Markov chains and SCFGs (stochastic context free grammar). Bayesian signal processing algorithms for CSCFGs with polynomial time complexity are also derived; finally, the target's kinematics are described by the baseline VSIMM (variable structure interacting multiple model). Based on the 3-level model, we present a novel CSCFG driven sequential particle filtering algorithm that estimates the target's states. This algorithm comprises a CSCFG meta-level parsing algorithm that operates in conjunction with a base-level VSIMM tracking algorithm. Extensive numerical results using simulated ground moving target indicator (GMTI) radar measurements show substantial improvement in target tracking accuracy compared with VSIMM tracker. To further evaluate the effectiveness of CSCFG, we also illustrate two anomalous trajectories for targets moving on grid roadmap. These trajectories show suspicious intents of targets and cause attention of radar operators. Numerical examples using simulated GMTI radar measurements show that CSCFG based Viterbi tracker can significantly decrease the tracking error compared with HMM (hidden Markov model) Viterbi tracker. Future work include more flexible constructions of the roadmap graph and extensions from CSCFGs to matrix grammars to model more complicated spatio-temporal trajectories.Applied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate
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Asuncion, Janice Sy. "The Geographic Adaptive Potential of Freight Transportation and Production System in the Context of Fuel and Emission Constraints." Thesis, University of Canterbury. Department of Mechanical Engineering, 2014. http://hdl.handle.net/10092/9230.
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Freight transportation is an integral element of various supply chains and has a complex and dynamical interrelationship with human economic activities. Modern logistical strategies paved way to the current supply chain organisation and logistics network design resulting in a more global economy and huge economies of scale. Recent trends of volatility of oil price have major implications in the movement of commodities across the supply chains. Likewise, climate change issues have presented urgent challenges in reducing carbon emissions for the transport and logistics sector. Pressure on the sector comes from both governments and consumers alike, demanding future sustainability as well as corporate environmental and social responsibility.
The original contribution of this research is to investigate the system-wide dynamics of freight transportation and production in the context of supply chains. A theoretical framework called the ‘Geographic Adaptive Potential’ or GAP is built to understand how constraints in energy and emissions affect the production and distribution of commodities. The changes in the supply chain were investigated in four different components, namely a) the potential to shift to less energy and emissions intensive modes for long-haul freight, b) logistical strategies in the last leg of the chain or urban freight and c) local production and distribution, and d) the accessibility of potential customers to the markets.
The design of the GAP components is in correspondence with the links of the supply chain. The analyses yielded an evaluation of the adaptive capacity of the freight transport and production system. For long-haul freight, a GIS-based model was created called the ‘New Zealand Intermodal Freight Network’ or NZIFN. It is an optimisation tool integrating the road, rail and shipping network of New Zealand and calculates that minimum time, operating costs, energy and emissions routes between 2 given locations. The case studies of Auckland to Wellington and Auckland to Christchurch distributions of non-perishable products established that even a marginal increase of rail and coastal shipping share produced around 10% reduction in both freight energy and greenhouse gas emissions.
In the study of the last leg of the supply chain, the truck trip generation rates of different food stores were investigated. The strongest factors influencing the trip rates to a store are its size and product variation, the latter being a new parameter introduced in the dissertation. It is defined as the total number of brands for 6 chosen commodities commonly found in the stores. The trip rates together with the truck type and distance travelled were used to compute the freight energy usage of the stores. Results revealed that supermarkets consume the most energy for their delivery operations but relative to its physical size, they are more energy efficient than smaller stores. This is due to the utilisation of advanced logistical strategies such as freight consolidation and the effective use of distribution centres.
The localised production chapter was explored in the context of Farmers’ markets and their difference with the conventional supermarket distribution system. Using a freight transport energy audit, the energy intensities of both systems were compared. The findings showed that Farmers’ markets were more energy-intensive than supermarkets owing to the low volumes of goods delivered to the market and the lack of freight consolidation effort in the system.
The study on the active mode access of potential customers to both Farmers’ markets and supermarkets captured the interplay between freight and personal transport and is the final component of GAP. The results of the ArcGIS based model called ‘Active Mode Access’ or AMA demonstrated that both Farmers’ markets and supermarkets have the same level of accessibility for walking or biking customers. However, the calculations also showed that almost 87% of New Zealanders have no AMA to stores and are at risk for fuel price increase.
Finally, the key result of this dissertation is the assessment that there is actually limited adaptive capacity of the freight transport and production system. This is due to network infrastructure and geographical constraints as well as commodity type and mode compatibility and other operational concerns. Due to these limitations, the GAP model assessed that reduction in energy and allowable emissions will ultimately reduce the amount of commodities moved in the system.
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Dell'Isola, Davide. "Optimization of DC/DC converters for embedded systems including dynamic constraints." Electronic Thesis or Diss., Université de Lorraine, 2020. http://www.theses.fr/2020LORR0124.
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Pour se conformer aux nouvelles normes d'émission et améliorer l’efficacité et l’autonomie des véhicules, le secteur des transports s'est tourné vers des solutions plus électriques. La compacité, le poids et l'efficacité sont alors des exigences primordiales dans les avions modernes ou dans les véhicules électriques/hybrides. Dès lors, la conception des éléments de conversion de puissance électrique demande un grand soin. Il est essentiel de proposer les solutions les plus compactes possibles et présentant les hauts rendements de conversion. Dans ce contexte, les matériaux semi-conducteurs à large bande interdite sont désormais reconnus comme étant les candidats les plus appropriés. En effet, ceux-ci se caractérisent par un comportement en commutation des plus rapide et par des pertes de puissance plus faibles (commutation et conduction), ce qui permet de réduire la taille des éléments passifs et de l'unité de refroidissement du convertisseur de puissance. Compte tenu de ces critères, cette étude a pour objectif le développement d'une procédure pour le dimensionnement optimale d'un convertisseur élévateur DC/DC350V/3kW. Le convertisseur a été conçu spécifiquement pour une structure d’alimentation d’un actionneur. Afin d'assurer la bonne interaction entre la charge (onduleur DC/AC et moteur) et le micro-réseau de bord, le dimensionnement doit prendre en compte la stabilité et le comportement dynamique du convertisseur lors d'une éventuelle variation du point de fonctionnement, donc sa stratégie de contrôle. Les alternatives technologiques à un tel problème sont multiples. Une sélection par algorithme génétique avec front de Pareto est proposée. La routine développée permet d’identifier les solutions à plus hauts rendement et compacité, tout en préservant la stabilité et le respect des spécifications, aussi bien en régime permanent que transitoireTo keep up with the new emission standards and improve efficiency and autonomy, the transportation sector has moved towards more electric solutions. Then, compactness, weight and efficiency are primary requirements in modern aircrafts or Electric/Hybrid vehicles. The power electronics units in the on-board electrical networks have to be designed accordingly, as it is essential to achieve very compact designs and energy conversion efficiencies very close to the unity. The wide bandgap semiconductor materials are considered as the future technology in the realization of high efficiency switched-mode power supplies. Such materials are featured by fast switching behaviour and low power losses, which allows reducing the size of the passive elements and the cooling unit of the power converter. Considering these criteria, the objective of this study concerns the development of a procedure for the optimal design of a DC/DC boost converter 350V/3kW. The converter has been designed specifically for a powertrain application. In order to ensure the proper interaction with the load (DC/AC inverter and motor) and the micro-grid on-board, the design must take into account the stability and dynamic behaviour of the converter during a possible variation of the operating point, then its control strategy. To deal with the manifold technical solutions and in order to reach the best trade-off, a Pareto front genetic approach is proposed. The developed routine consent to obtain the most convenient design solutions in terms of efficiency and compactness, which ensure the stability and the compliance with the design specification on both steady state and transients modes
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O'Hanlon, Catherine Grace. "Learning in context : linguistic and attentional constraints in the learning of colour and shape terms by three-year-olds." Thesis, University of Essex, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.429283.
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Borgh, Joakim. "Attribute-Based Encryption in Systems with Resource Constrained Devices in an Information Centric Networking Context." Thesis, Uppsala universitet, Avdelningen för datorteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-298215.
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An extensive analysis of attribute-based encryption (ABE) in systems with resource constrained devices is performed. Two system solutions of how ABE can be performed in such systems are proposed, one where the ABE operations are performed at the resource constrained devices and one where ABE is performed at a powerful server. The system solutions are discussed with three different ABE schemes. Two of the schemes are the traditional key policy ABE (KP-ABE) and ciphertext policy ABE (CP-ABE). The third scheme is using KP-ABE to simulate CP-ABE, in an attempt to benefit from KP-ABE being computationally cheaper than CP-ABE while maintaining the intuitive way of using CP-ABE. ABE is a computationally expensive encryption method which might not be feasible to perform at the resource constrained sensors, depending on the hardware. An implementation of a CP-ABE scheme with a 128 bit security level was written and used to evaluate the feasibility of ABE on a sensor equipped with an ARM Cortex-M3 processor having 32 kB RAM and 256 kB flash. It is possible to perform CP-ABE on the sensor used in this project. The limiting factor of feasibility of ABE on the sensor is the RAM size. In this case policy sizes up to 12 attributes can be performed on the sensor. The results give an idea of the feasibility of encryption with ABE on sensors. In addition to the results several ways of improving performance of ABE on the sensor are discussed.
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Dib, Djawida. "Optimizing PaaS provider profit under service level agreement constraints." Thesis, Rennes 1, 2014. http://www.theses.fr/2014REN1S044/document.
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L'informatique en nuage (cloud computing) est un paradigme émergent qui révolutionne l'utilisation et la commercialisation des services informatiques. De nos jours, l'impact socio-économique de l'informatique en nuage et plus particulièrement des services de PaaS (plate-forme en tant que service) devient essentiel, puisque le nombre d'utilisateurs et de fournisseurs des cloud PaaS est en pleine croissance. L'objectif principal des fournisseurs de cloud PaaS est de générer le maximum de profit des services qu'ils fournissent. Cela les oblige à faire face à un certain nombre de défis, tels que la gestion efficace des ressources sous-jacentes et la satisfaction des SLAs (contrat de service) des applications hébergées. Dans cette thèse, nous considérons un environnement PaaS hybride de cloud bursting, où le fournisseur PaaS possède un nombre limité de ressources privées et a la possibilité de louer des ressources publiques. Ce choix permet au fournisseur PaaS d'avoir un contrôle complet sur les services hébergés dans les ressources privées et de profiter de ressources publiques pour gérer les périodes de pointe. De plus, nous proposons une solution rentable pour gérer un tel système PaaS sous des contraintes de SLA. Nous définissons une politique d'optimisation de profit qui, à chaque requête d'un nouveau client, évalue le coût d'hébergement de son application en utilisant les ressources publiques et privées et choisit l'option qui génère le plus de profit. Pendant les périodes de pointe la politique considère deux autres options. La première option consiste à emprunter quelques ressources aux applications en cours d'exécution tout en considérant le paiement de pénalités si leur qualité de service est affectée. La seconde option consiste à attendre que des ressources privées soient libérés tout en considérant le paiement de pénalités si la qualité de service de la nouvelle application est affectée. En outre, nous avons conçu et mis en œuvre une architecture de cloud PaaS, appelée Meryn, qui intègre la politique d'optimisation proposée, supporte le cloud bursting et héberge des applications du type batch et MapReduce. Les résultats de notre évaluation montrent l'efficacité de notre approche dans l'optimisation du profit du fournisseur. En effet, comparée à une approche de base, notre approche fournit jusqu'à 11.59 % et 9.02 % plus de profits pour le fournisseur dans respectivement les simulations et les expériencesCloud computing is an emerging paradigm revolutionizing the use and marketing of information technology. As the number of cloud users and providers grows, the socio-economical impact of cloud solutions and particularly PaaS (platform as a service) solutions is becoming increasingly critical. The main objective of PaaS providers is to generate the maximum profit from the services they provide. This requires them to face a number of challenges such as efficiently managing the underlying resources and satisfying the SLAs of the hosted applications. This thesis considers a cloud-bursting PaaS environment where the PaaS provider owns a limited number of private resources and is able to rent public cloud resources, when needed. This environment enables the PaaS provider to have full control over services hosted on the private cloud and to take advantage of public clouds for managing peak periods. In this context, we propose a profit-efficient solution for managing the cloud-bursting PaaS system under SLA constraints. We define a profit optimization policy that, after each client request, evaluates the cost of hosting the application using public and private resources and chooses the option that generates the highest profit. During peak periods the optimization policy considers two more options. The first option is to take some resources from running applications, taking into account the payment of penalties if their promised quality of service is affected. The second option is to wait until private resources become available, taking into account the payment of penalties if the promised quality of service of the new application is affected. Furthermore we designed and implemented an open cloud-bursting PaaS system, called Meryn, which integrates the proposed optimization policy and provides support for batch and MapReduce applications. The results of our evaluation show the effectiveness of our approach in optimizing the provider profit. Indeed, compared to a basic approach, our approach provides up to 11.59% and 9.02% more provider profit in, respectively, simulations and experiments
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Souleiman, Isman Yahyeh. "Analyse de quelques problèmes de contact glissant." Thesis, Perpignan, 2017. http://www.theses.fr/2017PERP0010/document.
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Les phénomènes de contact impliquant des corps déformables abondent dans l'industrie, notamment dans les structures mécaniques. En raison de leur complexité intrinsèque, les phénomènes de contact sont modélisés à l'aide de problèmes aux limites fortement non linéaires. De ce fait, la modélisation de ces phénomènes pose plusieurs difficultés mathématiques. Dans cette thèse, nous nous intéressons à la modélisation, l'analyse variationnelle et l'analyse numérique de problèmes de contact glissant intervenant en mécanique des solides, pour des matériaux élastiques, viscoélastiques et viscoplastiques. La première partie de cette thèse rappelle quelques résultats préliminaires, notamment des outils mathématiques et mécaniques nécessaires pour réaliser la suite de ce travail. La deuxième partie est consacrée à l'étude de quelques problèmes de contact glissant sous diverses conditions de contact et frottement. Pour chacun de ces problèmes, nous introduisons les formulations fortes et des formulations variationnelles. Ensuite, nous obtenons des résultats d'existence et d'unicité des solutions faibles, sous certaines hypothèses de petitesse, ainsi que des résultats de convergence. Enfin, nous proposons une approximation numérique de certains problèmes de contact à l'aide de schémas discrétisés. Pour ces schémas, nous obtenons des résultats d'estimation de l'erreurContact phenomena involving deformable bodies abound in industry, especially in mechanical structures. Due to their intrinsic complexity, contact phenomena are modelled with strongly nonlinear boundary problems. For this reason, the modelling of these phenomena gives rise to various mathematical difficulties. In this thesis, we are interested in the modelling, the variational analysis and the numerical analysis of problems of sliding contact in solid mechanics for elastic, viscoelastic and viscoplastic materials. The first part of this thesis concerns some preliminary results, in particular the mathematical and mechanical tools necessary to carry out the continuation of this work. The second part is devoted to the study of some problems of sliding contact under various conditions of contact and friction. For each of these problems, we introduce strong formulations and variational formulations. Then, we obtain results of existence and uniqueness of the weak solutions, under smallness assumptions, as well as results of convergence. Finally, we propose a numerical approximation of some contact problems based on the etudy of discretized schemes. For these schemes we obtain error estimates results
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Roney, Joshua. "Evaluating Teaching Grammar in Specific Constraints of Context: A Pilot Study in the Developmental Writing Program at Seminole State College." Master's thesis, University of Central Florida, 2012. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5469.
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This pilot study investigated the efficacy of a supplemental Active Learning intervention that was administered with grammar workbook software in remedial-level composition classrooms at Seminole State College. The study analyzed student response data in a pre-test and post-test instrument in four classrooms; two followed standard methods while two incorporated the additional experimental intervention. The groups are identified in this study as either “Standard” or “Experimental,” according to the method administered in the classroom. The intervention was designed based on five grammar topic areas which correspond with content assessed in the pre-test and post-test. The Active Learning method required students to prepare a short, guided presentation on selected grammar topics. Findings showed that there was no significant change in improvement between the pre-test and post-test among the Standard or the Experimental groups, due in part to a relatively small sample size. A positive change approaching significant level occurred in the Experimental group in topic areas related to critical thinking. No significant or near-significant change was observed in the topic areas related to memorization in either group. Recommendations were made for further sampling, modification, and future applications of the intervention used in the study and for continued testing of grammar software used for instruction in Developmental Writing classes at Seminole State College.M.A.
Masters
English
Arts and Humanities
English; Rhetoric and Composition
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Iqbal, Muhammad Aamir. "Distributed Security Paradigm for Resource-constrained Wireless Sensors in the Context of Internet of Things (IoT)." Thesis, University of Louisiana at Lafayette, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10254391.
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This dissertation addresses new challenges in the Internet of Things (IoT) related to security and privacy. The current transition from legacy internet to Internet of Things leads to multiple changes in its communication paradigms. Today's Machine to Machine (M2M) and Internet of Things architectures further accentuated this trend, not only by involving wider architectures but also by adding heterogeneity, resource capabilities inconstancy, and autonomy to once uniform and deterministic systems and the issue of scalability within a WSN. Unlike internet servers, most of IoT components are characterized by low capabilities in terms of both energy and computing resources and thus, are unable to support complex security schemes. A direct use of existing key establishment protocols to initiate connections between two IoT entities may be impractical unless both endpoints are able to run the required (expensive) cryptographic primitives, thus leaving aside a whole class of resource constrained devices. In this dissertation, we propose novel security solution approaches for key establishments designed to reduce the requirements of existing security protocols in order to be supported by resource-constrained devices and for the scalability of sensors with a WSN in contest of IoT. We have investigated the feasibility of substituting the key management scheme of ZigBee stack by implementing LEAP+ to enhance its security and scalability capabilities in a WSN. LEAP+ is surprisingly well-suited to different types of network topologies, device types, and addressing modes offered by ZigBee stack, resolving the issue of scalability due to ZigBee’s key management centralized approach, and our experimental results and performance evaluation parameters illustrated these facts. We designed new key establishment protocols for the constrained wireless sensors to delegate their heavy cryptographic load to less constrained nodes in their neighborhood, exploiting the spatial heterogeneity of IoT nodes. Allowing cooperation between sensor nodes may open the way to a new class of threats, known as internal attacks, that conventional cryptographic mechanisms fail to deal with. This introduces the concept of trustworthiness within a cooperative group. Proposed protocols aim to track nodes behaviors and past performances to detect their trustworthiness and select reliable ones for cooperative assistance. Sensor nodes’ trustworthiness is verified by accompanying them with an accelerometer to detect whether these cooperative sensors are installed on the same body. Based on an extensive analysis and their accelerometers’ data correlations with the base station (mobile phone in this case) accelerometer data, we identify a set of neighboring devices able to provide assistance in performing heavy asymmetric computations effectively without compromising the security of the whole system. Formal security and privacy verifications and performance analyses with respect to the resource-constrained sensor’s energy are also conducted to ensure the security effectiveness and energy efficiency of our proposed protocols.
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Young, Doug. "Caring within constraint : employment relations in voluntary sector social care in the context of personalisation, marketization and austerity." Thesis, University of Strathclyde, 2018. http://digitool.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=30650.
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This thesis examines the impact of personalisation, marketization and austerity on voluntary sector social care employment relations in post-recession Scotland. The prevalence of short-term funding contracts characterised by strict and often confining performance criteria has resulted in the emergence of a 'contract culture' whereby funders effectively determine service provision. This quasi-market approach to procurement often manifests itself in a pronounced deterioration in terms and conditions of employment, and an intensification of work. Personalisation is premised on the notion of empowering service users, which many studies have found increases their satisfaction and wellbeing. However, due to its dual imperative of increasing quality and reducing cost, personalisation can serve to significantly intensify work. In this sense, the demands of austerity and personalisation converge, and create a compound pressure on the voluntary sector employment relationship. In consequence, this research examines firstly, the implications of austerity and personalisation on voluntary sector employment policies; secondly, the impact of subsequent changes to employment policies within voluntary sector organisations on the attitudes of employees; and finally, whether or not these changes in attitudes create tensions between employees and management. At an empirical level, this research provides analysis of four comprehensive case studies, comprised of fifty-five interviews overall and a benchmarking survey of each, situated in the under-researched context of voluntary sector social care in Scotland. This is of pressing importance, given that the UK voluntary sector has grown considerably in recent years (NCVO, 2017), and in light of a growing and aging UK population (ONS, 2017), looks set to continue to do so. This research makes a conceptual contribution to knowledge via a unique conceptual framework, based on the sociology of service work and the psychological contract, as an instrument through which to better understand how personalisation and austerity affect the employment relationship. In doing so, it provides the scope to identify specific issues affecting the workforce, how they respond to them, and what this means for employers, and the sector at large.
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Diallo, Thierno Mahamoudou. "Discovering data quality rules in a master data management context." Thesis, Lyon, INSA, 2013. http://www.theses.fr/2013ISAL0067.
Full textAbstract:
Le manque de qualité des données continue d'avoir un impact considérable pour les entreprises. Ces problèmes, aggravés par la quantité de plus en plus croissante de données échangées, entrainent entre autres un surcoût financier et un rallongement des délais. De ce fait, trouver des techniques efficaces de correction des données est un sujet de plus en plus pertinent pour la communauté scientifique des bases de données. Par exemple, certaines classes de contraintes comme les Dépendances Fonctionnelles Conditionnelles (DFCs) ont été récemment introduites pour le nettoyage de données. Les méthodes de nettoyage basées sur les CFDs sont efficaces pour capturer les erreurs mais sont limitées pour les corriger . L’essor récent de la gestion de données de référence plus connu sous le sigle MDM (Master Data Management) a permis l'introduction d'une nouvelle classe de règle de qualité de données: les Règles d’Édition (RE) qui permettent d'identifier les attributs en erreur et de proposer les valeurs correctes correspondantes issues des données de référence. Ces derniers étant de très bonne qualité. Cependant, concevoir ces règles manuellement est un processus long et coûteux. Dans cette thèse nous développons des techniques pour découvrir de manière automatique les RE à partir des données source et des données de référence. Nous proposons une nouvelle sémantique des RE basée sur la satisfaction. Grace à cette nouvelle sémantique le problème de découverte des RE se révèle être une combinaison de la découverte des DFCs et de l'extraction des correspondances entre attributs source et attributs des données de référence. Nous abordons d'abord la découverte des DFCs, en particulier la classe des DFCs constantes très expressives pour la détection d'incohérence. Nous étendons des techniques conçues pour la découverte des traditionnelles dépendances fonctionnelles. Nous proposons ensuite une méthode basée sur les dépendances d'inclusion pour extraire les correspondances entre attributs source et attributs des données de référence avant de construire de manière automatique les RE. Enfin nous proposons quelques heuristiques d'application des ER pour le nettoyage de données. Les techniques ont été implémenté et évalué sur des données synthétiques et réelles montrant la faisabilité et la robustesse de nos propositionsDirty data continues to be an important issue for companies. The datawarehouse institute [Eckerson, 2002], [Rockwell, 2012] stated poor data costs US businesses $611 billion dollars annually and erroneously priced data in retail databases costs US customers $2.5 billion each year. Data quality becomes more and more critical. The database community pays a particular attention to this subject where a variety of integrity constraints like Conditional Functional Dependencies (CFD) have been studied for data cleaning. Repair techniques based on these constraints are precise to catch inconsistencies but are limited on how to exactly correct data. Master data brings a new alternative for data cleaning with respect to it quality property. Thanks to the growing importance of Master Data Management (MDM), a new class of data quality rule known as Editing Rules (ER) tells how to fix errors, pointing which attributes are wrong and what values they should take. The intuition is to correct dirty data using high quality data from the master. However, finding data quality rules is an expensive process that involves intensive manual efforts. It remains unrealistic to rely on human designers. In this thesis, we develop pattern mining techniques for discovering ER from existing source relations with respect to master relations. In this set- ting, we propose a new semantics of ER taking advantage of both source and master data. Thanks to the semantics proposed in term of satisfaction, the discovery problem of ER turns out to be strongly related to the discovery of both CFD and one-to-one correspondences between sources and target attributes. We first attack the problem of discovering CFD. We concentrate our attention to the particular class of constant CFD known as very expressive to detect inconsistencies. We extend some well know concepts introduced for traditional Functional Dependencies to solve the discovery problem of CFD. Secondly, we propose a method based on INclusion Dependencies to extract one-to-one correspondences from source to master attributes before automatically building ER. Finally we propose some heuristics of applying ER to clean data. We have implemented and evaluated our techniques on both real life and synthetic databases. Experiments show both the feasibility, the scalability and the robustness of our proposal