• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 12
  • 2
  • 1
  • Tagged with
  • 20
  • 5
  • 4
  • 4
  • 3
  • 3
  • 3
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Synthesizing motion sequences from sample motions to satisfy environmental constraints

Liu, Yanrui 01 January 2014 (has links) (PDF)
Complex realistic human motion sequences satisfying environmental constraints can be created by motion capture, which is a reliable way to reproduce human motions. However, motion capture data is difficult to modify in order to obtain variant motion sequences for multiple tasks. In this thesis, a system for synthesizing complex realistic human motion sequences based on a small group of sample motions to satisfy constraints is proposed. Methods are proposed for the system to preprocesses raw motion capture data to create sample motions that can be easily modified for the purpose of meeting specific requirements, while maintaining the subtleties of the origin motion capture data. Methods for the system to scan user-input constraints, to choose the best sample motion and synthesize the motion sequence based on route affected by the constraint are also proposed. Each generated motion piece is blended with the default motion, and thus a motion sequence composed of several pieces of motion based on constraints will be generated. Artifacts that arise during motion generation are identified and handled properly. Experimental results will show that the system can create cyclical sample motions from motion capture data, generate motion pieces based on environmental constraints, and synthesize complex realistic human motion sequences.
12

A Study of Penicillin Binding Proteins in Mycobacterium Tuberculosis

Anderson, Lisa Louise 11 October 2001 (has links)
No description available.
13

Synthetic Applications of Ketene Cycloadditions Lactams and Coumarins

Shieh, Chia Hui 08 1900 (has links)
The objective of this study was to develop new synthetical routes to natural and industrial products utilizing ketene cycioaddition reactions. The cycioaddition of diphenylketene with α,β-unsaturated imines yields (2+2) cycioaddition products, g-lactams. However, electron donating groups, such as dimethylamine, in the 4-position of the α,β-unsaturated imines result in (4+2) cycloaddition products, ∂-lactams. Dichloroketene reacted with α,β-unsaturated imines to yield (4+2) cycloaddition products, g-lactams. Large substituents in the 4-position of a, ^-unsaturated imines resulted in a (2+2) cycioaddition product, β-lactam. The ∂-lactams derived from dichloroketene are easily dehydrochlorinated to the corresponding 2-pyridornes.
14

Modelos de sintetização plena e reduzida de erros em máquinas de medir por coordenadas / Synthesizing technique and reduced synthesizing technique of errors in coordinate measuring machines

Morais, César Augusto Galvão de 02 March 2012 (has links)
A atual competitividade da economia mundial exige um controle de qualidade sofisticado em indústrias de manufatura, pois, devido ao grande número de empresas do setor são constantes as exigências de melhorias na produção. Deste modo, sistemas de medição rápidos, precisos e flexíveis como a MMC (Máquina de Medir por Coordenada) são introduzidos junto ao processo produtivo e, no que se refere à inspeção dimensional, eles proporcionam os quesitos pretendidos. Como todas as máquinas, a MMC está suscetível a erros, o que resulta em valores errôneos de sua resposta de leitura. Neste contexto, o objetivo principal do trabalho é descrever uma metodologia para efetuar um levantamento de erros em uma MMC, equacionando e quantificando nas suas direções preferenciais os erros incidentes durante um procedimento de medição. O levantamento de erros foi realizado em uma MMC do tipo ponte móvel sob as formas, teórica e experimental. A metodologia aplicada sob a forma teórica foi elaborada pelo método reduzido de sintetização de erros e pelo método pleno de sintetização de erros. Para estas sintetizações foram desenvolvidos matematicamente modelos da máquina por meio de uma análise de sua estrutura e também utilizando a teoria das transformações homogêneas. O levantamento de erros sob a forma experimental, sintetização experimental de erros, foi realizado de forma plena, obtendo valores dos 21 erros individuais. Para este método, foi utilizado canhão laser de medição, conjunto de óticas de medição por interferometria, apalpador eletrônico, nível eletrônico, esquadro mecânico de granito, além de dispositivos de fixação. Por meio dos valores obtidos na sintetização experimental permitiu-se conhecer a influência dos erros na ponta da sonda de medição. Os resultados mostraram que o eixo \"Z\" apresentou os menores erros de rotação, com amplitude menor que 1,7 arcoseg, contrariamente aos eixos \"X\" e \"Y\". Constatou-se que as sintetizações de erros apresentadas podem ser empregadas como técnica de error budget, pois permitem conhecer os erros da máquina de medir por coordenadas e também rastreá-los em todo o seu volume de trabalho. / The current competitiveness of the global economy requires a sophisticated quality control in manufacturing industries, because, due to the large number of companies in this sector are constant the requirements of improvements in production. Thus, fast, accurate and flexible, systems of measurement as the CMM (Coordinate Measuring Machine) are introduced at production process and, with respect to dimensional inspection, this provides the qualities intended. Like all machines, the CMM is susceptible to errors, resulting in erroneous values of their reading response. In this context, the main objective of the study is to describe a methodology of error budget in a CMM, equating and quantifying in their preferred directions the errors incidents during a measurement procedure. The error budget was held in a moving bridge CMM in the forms, theoretical and experimental. The methodology applied in the theoretical form was developed by the method of reduced synthesizing technique of errors and the method of synthesizing technique of errors. For these synths were developed mathematical models of the machine by way of an analysis of its structure and also using the homogeneous transformations. The experimental synthesizing technique of errors was made with obtaining the individual values of 21 errors. For this method, was used a laser measurement, optical set of measurement by interferometry, electronic probe, electronic level, granite square, and fixation devices. Through the values obtained in the experimental synthesizing technique enabled to know the influence of errors on the tip of the probe. The results showed that the \"Z\" axis had the lowest errors of rotation, with amplitude less than 1.7 arcoseg, contrary to the axis \"X\" and \"Y\". It was verified that the methods of synthesizing technique of errors can be used as error budget, because they provide to know the errors of a coordinate measuring machine and also trace them throughout their volume.
15

The synthesizing capacity of metabolic networks

Handorf, Thomas 12 September 2008 (has links)
In dieser Arbeit wird das Konzept der Scopes und auf großskalige metabolische Netzwerke angewendet. Scopes beschreiben die Synthesekapazität eines Netzwerkes, wenn dieses mit bestimmten Ausgangsstoffen versorgt wird. Dabei werden für definierte Ausgangsstoffe alle durch das Netzwerk synthetisierbaren Stoffe berechnet. In dieser Arbeit wird insbesondere das Referenznetzwerk der KEGG-Datenbank untersucht, welches Reaktionen unabhängig von ihrem Vorkommen in unterschiedlichen Organismen enthält. Es werden die Synthesekapazitäten systematisch für alle Einzelstoffe und für einige Stoffkombinationen errechnet und untersucht. Der Effekt von Kofaktoren wird analysiert. Desweiteren ist es möglich, Kombinationen von Ausgangsstoffen zu finden, aus denen wichtige Metabolite der Zelle produziert werden können. Somit kann der Nährstoffbedarf einer Zelle abgeschätzt werden. Im zweiten Teil wird eine Hierarchie der Scopes basierend auf Inklusionsrelationen zwischen diesen erstellt. Diese Hierarchie kann mit der chemischen Komposition der enthaltenen Stoffe, also mit deren chemischen Bausteinen, den Elementen oder Gruppen, in Verbindung gebracht werden. Dabei erhalten Scopes mit sehr häufigen Bausteinkombinationen eine hervorgehobene Rolle in der Hierarchie. Die Scopehierarchie kann mit der Autotrophie des Netzwerkes in Zusammenhang gebracht werden. Der dritte Teil beschäftigt sich mit möglichen Änderungen in der Topologie des Netzwerkes und deren Auswirkungen auf die Scopes. Es stellt sich heraus, dass die Synthesekapazitäten sich im allgemeinen sehr robust gegenüber solchen Veränderungen verhalten. Die Methodik ist im übrigen auch geeignet um Lücken im biochemischen Wissen aufzuspühren und dadurch die Kenntnisse über den Metabolismus zu erweitern. Außerdem zeigen die getätigten Analysen evolutionäre Ziele hinter der Konstruktion metabolischer Netzwerke auf. / In this work, the concept of scopes is introduced and applied to large scale metabolic networks. The scopes represent functional measures, describing the synthesizing capacity of a metabolic network if supplied with a predefined set of resources. For a given set of initial metabolites, the seed, all possible products are determined using the stoichiometric information of the network. Specifically, the organism independent KEGG reference network is analyzed. The first part of this work describes possible applications of the scopes, including the determination of the synthesizing capacities of different compounds and sets of compounds, the study of the effect of cofactors on the capacities of metabolic networks or the identification of possible nutrient sets required for the maintenance of a cell. In the second part, the scopes of different seed compounds are systematically analyzed and put in relation to one another. A hierarchy is generated representing the inclusion relations of the scopes. Interestingly, this hierarchy reflects the chemical composition, i.e. the chemical elements or chemical groups of the contained compounds. Scopes containing frequently used chemical elements or groups are represented by high degree nodes in this hierarchy. A subhierarchy of these characteristic scopes is described and brought in relation to the autotrophy of the network. In the third part, the effect of modifications in the topology of metabolic networks is analyzed. It turns out that the scopes are generally robust against the deletion of single and even multiple reactions. Also, the influence of limitations in the metabolic knowledge on the results is discussed and possibilities for improvements are indicated. The performed analyses reveal evolutionary objectives behind the construction of metabolic networks. In particular, hypotheses about design, autotrophy or robustness of metabolic networks can be inferred.
16

Modelos de sintetização plena e reduzida de erros em máquinas de medir por coordenadas / Synthesizing technique and reduced synthesizing technique of errors in coordinate measuring machines

César Augusto Galvão de Morais 02 March 2012 (has links)
A atual competitividade da economia mundial exige um controle de qualidade sofisticado em indústrias de manufatura, pois, devido ao grande número de empresas do setor são constantes as exigências de melhorias na produção. Deste modo, sistemas de medição rápidos, precisos e flexíveis como a MMC (Máquina de Medir por Coordenada) são introduzidos junto ao processo produtivo e, no que se refere à inspeção dimensional, eles proporcionam os quesitos pretendidos. Como todas as máquinas, a MMC está suscetível a erros, o que resulta em valores errôneos de sua resposta de leitura. Neste contexto, o objetivo principal do trabalho é descrever uma metodologia para efetuar um levantamento de erros em uma MMC, equacionando e quantificando nas suas direções preferenciais os erros incidentes durante um procedimento de medição. O levantamento de erros foi realizado em uma MMC do tipo ponte móvel sob as formas, teórica e experimental. A metodologia aplicada sob a forma teórica foi elaborada pelo método reduzido de sintetização de erros e pelo método pleno de sintetização de erros. Para estas sintetizações foram desenvolvidos matematicamente modelos da máquina por meio de uma análise de sua estrutura e também utilizando a teoria das transformações homogêneas. O levantamento de erros sob a forma experimental, sintetização experimental de erros, foi realizado de forma plena, obtendo valores dos 21 erros individuais. Para este método, foi utilizado canhão laser de medição, conjunto de óticas de medição por interferometria, apalpador eletrônico, nível eletrônico, esquadro mecânico de granito, além de dispositivos de fixação. Por meio dos valores obtidos na sintetização experimental permitiu-se conhecer a influência dos erros na ponta da sonda de medição. Os resultados mostraram que o eixo \"Z\" apresentou os menores erros de rotação, com amplitude menor que 1,7 arcoseg, contrariamente aos eixos \"X\" e \"Y\". Constatou-se que as sintetizações de erros apresentadas podem ser empregadas como técnica de error budget, pois permitem conhecer os erros da máquina de medir por coordenadas e também rastreá-los em todo o seu volume de trabalho. / The current competitiveness of the global economy requires a sophisticated quality control in manufacturing industries, because, due to the large number of companies in this sector are constant the requirements of improvements in production. Thus, fast, accurate and flexible, systems of measurement as the CMM (Coordinate Measuring Machine) are introduced at production process and, with respect to dimensional inspection, this provides the qualities intended. Like all machines, the CMM is susceptible to errors, resulting in erroneous values of their reading response. In this context, the main objective of the study is to describe a methodology of error budget in a CMM, equating and quantifying in their preferred directions the errors incidents during a measurement procedure. The error budget was held in a moving bridge CMM in the forms, theoretical and experimental. The methodology applied in the theoretical form was developed by the method of reduced synthesizing technique of errors and the method of synthesizing technique of errors. For these synths were developed mathematical models of the machine by way of an analysis of its structure and also using the homogeneous transformations. The experimental synthesizing technique of errors was made with obtaining the individual values of 21 errors. For this method, was used a laser measurement, optical set of measurement by interferometry, electronic probe, electronic level, granite square, and fixation devices. Through the values obtained in the experimental synthesizing technique enabled to know the influence of errors on the tip of the probe. The results showed that the \"Z\" axis had the lowest errors of rotation, with amplitude less than 1.7 arcoseg, contrary to the axis \"X\" and \"Y\". It was verified that the methods of synthesizing technique of errors can be used as error budget, because they provide to know the errors of a coordinate measuring machine and also trace them throughout their volume.
17

Autonomous Resource Allocation in Clouds: A Comprehensive Analysis of Single Synthesizing Criterion and Outranking Based Multiple Criteria Decision Analysis Methods

Akbulut, Yagmur 20 August 2014 (has links)
Cloud computing is an emerging trend where clients are billed for services on a pay-per-use basis. Service level agreements define the formal negotiations between the clients and the service providers on common metrics such as processing power, memory and bandwidth. In the case of service level agreement violations, the service provider is penalised. From service provider's point of view, providing cloud services efficiently within the negotiated metrics is an important problem. Particularly, in large-scale data center settings, manual administration for resource allocation is not a feasible option. Service providers aim to maximize resource utilization in the data center, as well as, avoiding service level agreement violations. On the other hand, from the client's point of view, the cloud must continuously ensure enough resources to the changing workloads of hosted application environments and services. Therefore, an autonomous cloud manager that is capable of dynamically allocating resources in order to satisfy both the client and the service provider's requirements emerges as a necessity. In this thesis, we focus on the autonomous resource allocation in cloud computing environments. A distributed resource consolidation manager for clouds, called IMPROMPTU, was introduced in our previous studies. IMPROMPTU adopts a threshold based reactive design where each unique physical machine is coupled with an autonomous node agent that manages resource consolidation independently from the rest of the autonomous node agents. In our previous studies, IMPROMPTU demonstrated the viability of Multiple Criteria Decision Analysis (MCDA) to provide resource consolidation management that simultaneously achieves lower numbers of reconfiguration events and service level agreement violations under the management of three well-known outranking-based methods called PROMETHEE II, ELECTRE III and PAMSSEM II. The interesting question of whether more efficient single synthesizing criterion and outranking based MCDA methods exist was left open for research. This thesis addresses these limitations by analysing the capabilities of IMPROMPTU using a comprehensive set of single synthesizing criterion and outranking based MCDA methods in the context of dynamic resource allocation. The performances of PROMETHEE II, ELECTRE III, PAMSSEM II, REGIME, ORESTE, QUALIFEX, AHP and SMART are investigated by in-depth analysis of simulation results. Most importantly, the question of what denotes the properties of good MCDA methods for this problem domain is answered. / Graduate / 0984
18

EVALUATING PERFORMANCE OF GENERATIVE MODELS FOR TIME SERIES SYNTHESIS

Haris, Muhammad Junaid January 2023 (has links)
Motivated by successes in the image generation domain, this thesis presents a novel Hybrid VQ-VAE (H-VQ-VAE) approach for generating realistic synthetic time series data with categorical features. The primary motivation behind this work is to address the limitations of existing generative models in accurately capturing the underlying structure and patterns of time series data, especially when dealing with categorical features.  Our proposed H-VQ-VAE model builds upon the foundation of the VQ-VAE architecture and consists of two separate VQ-VAEs: the whole VQ-VAE and the sliding VQ-VAE. Both models share a ResNet-based architecture with conv1d layers to effectively capture the temporal structure within the time series data. The whole VQ-VAE focuses on entire sequences of data to learn relationships between categorical and numerical features, while the sliding VQ-VAE exclusively processes numerical features using a sliding window approach. We conducted experiments on multiple datasets to evaluate the performance of our H-VQ-VAE model in comparison with the original VQ-VAE and TimeGAN models. Our evaluation used a train-on-real and test-on-synthetic approach, focusing on metrics such as Mean Absolute Error (MAE) and Explained Variance (EV). The H-VQ-VAE model achieved a 25-50% better MAE for numerical features compared to the VQ-VAE and outperformed TimeGAN by 45-75% on the complex dataset indicating its effectiveness in capturing the underlying structure and patterns of the time series data. In conclusion, the H-VQ-VAE model offers a promising approach for generating realistic synthetic time series data with categorical features, with potential applications in various fields where accurate data generation is crucial.
19

Applications and development of acoustic and microwave atomic force microscopy for high resolution tomography analysis / Applications et développement des microscopies à force atomique acoustique et micro-onde pour l'analyse tomographique haute résolution

Vitry, Pauline 10 June 2016 (has links)
La microscopie à force atomique (AFM) est un outil de caractérisation d’échantillons tant organiques qu’inorganiques d’intérêt en physique, en biologie et en métallurgie. Le champ d’investigation de la microscopie AFM reste néanmoins restreint à l’étude des propriétés surfaciques des échantillons et la caractérisation sub-surfacique à l’échelle nanométrique n’est pas envisageable au-delà de la nano-indentation. Lors de ce travail, nous nous sommes intéressés à deux techniques de sonde locale complémentaires pour l’investigation volumique haute résolution.La première technique proposée est la microscopie de champ proche ultrasonore (MS-AFM), mise en place et exploitée en collaboration avec Dr. L. Tétard de l’Université Centrale de Floride. Cette technique fournie des informations localisées en profondeur en utilisant des ondes acoustiques dans la gamme de fréquences du MHz. Une étude complète de l’influence des paramètres de fréquences a été réalisée sur des échantillons de calibration et a permis de valider un modèle d’interprétation numérique. Cette technique ultrasonore, non invasive, a été appliquée à la caractérisation de vésicules lipidiques au sein de bactéries lors d’une collaboration avec les Pr. A. Dazzi et M.-J. Virolle, de l’Université Paris Sud Orsay. Un couplage a été réalisé avec la microscopie AFM infra-rouge (AFM-IR). Cette étude a démontré le potentiel d’investigation et d’analyse volumique et chimique d’échantillons biologiques.La seconde technique étudiée est la microscopie micro-onde (SMM), développée en collaboration avec la société Keysight. Cette technique, tout comme la microscopie acoustique, est non invasive et conduit à une caractérisation physico-chimique basée sur l’interaction de micro-ondes (0.2-16 GHz) avec la matière. Dans le cas de métaux, un lien entre la fréquence et la profondeur d’investigation a été mis en évidence. Cette technique a été appliquée à l’étude de la diffusion d’élément chimique léger au sein de métaux et à la mesure des propriétés mécaniques des matériaux. L’ensemble de ces résultats ouvre un nouveau champ d’investigation de la tomographie 3D dans l’analyse volumique à l’échelle nanométrique que ce soit dans le domaine de la biologie ou de la métallurgie. / The atomic force microscope (AFM) is a powerful tool for the characterization of organic and inorganic materials of interest in physics, biology and metallurgy. However, conventional scanning probe microscopy techniques are limited to the probing surface properties, while the subsurface analysis remains difficult beyond nanoindentation methods. Thus, the present thesis is focused on two novel complementary scanning probe techniques for high-resolution volumetric investigation that were develop to tackle this persisting challenge in nanometrology. The first technique considered, called Mode Synthesizing Atomic Force Microscopy (MSAFM), has been exploited in collaboration with Dr. Laurene Tetard of University of Central Florida to explore the volume of materials with high spatial resolution by means of mechanical actuation of the tip and the sample with acoustic waves of frequencies in the MHz range. A comprehensive study of the impact of the frequency parameters on the performance of subsurface imaging has been conducted through the use of calibrated samples and led to the validation of a numerical model for quantitative interpretation. Furthermore, this non-invasive technique has been utilized to locate lipid vesicles inside bacteria (in collaboration with Pr. A. Dazzi and M.-J. Virolle of Université Paris Sud, Orsay). Furthermore, we have combined this ultrasonic approach with infra-red microscopy, to add chemical speciation aimed at identifying the subsurface features, which represents a great advance for volume and chemical characterization of biological samples. The second technique considered is the Scanning Microwave Microscopy, which was developed in collaboration with Keysight society. Similar to acoustic-based microscopy, this non-invasive technique provided physical and chemical characterizations based on the interaction of micro-waves radiations with the matter (with frequency ranging from 0.2 and 16 GHz). Particularly, for metallic samples we performed volumetric characterization based on the skin effect of the materials. On the other hand, we have used this technique to analyze the diffusion of light chemical elements in metals and measured the effect of changes in mechanical properties of materials on their conductivity.Overall, these results constitute a new line of research involving non-destructive subsurface high resolution analysis by means of the AFM of great potential for several fields of research.
20

Synthesizing at the Graduate Student Level: Case Studies of Composing the Doctoral Candidacy Examination Essay

Akinkugbe, Morayo Omosalewa January 2021 (has links)
No description available.

Page generated in 0.0526 seconds