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  • 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.
31

The Comparative Research between the Efficiencies of the Police Stations of the Police Bureau of the Kaohsiung City Government An Application of the Three-Stage DEA Approach

Chen, Tsung-min 25 June 2009 (has links)
This research use three phase stage- Data Envelopment Analysis to examine 49 police stations, 10 police precincts of Kaohsiung City Government Police Bureau(KCGPB) from 2003 to 2007 regarding the statistical data of KCGPB. In phase one, using SBM-DEA method analyses the management efficiency and the amount of input and output variable. In second phase, using SFA regression analyses to probe into the environmental variable influencing degree to each police station of KCGPB. In addition, it takes account of the environmental effect and the random interference effect to improve input and output variable. Finally, by way of DEA and Malmguist productivity index, it can measure the relative effects and the productivity change situations between each police station. The model result shows that SBM-DEA can weigh input difference and total output difference at the same time, by the way of using ratio adjustment, it can determine the really administration efficiency of every police station. According to phase one analysis results, 245 DMUs efficiency values are below 1, it is almost 100% of all the DMUs efficiency values and shows that still have very big improvement space. By the regression analysis of phase 2, we know that the environmental parameter will exert an huge influence on input and output difference, in which the most influence is the environmental parameters of violence crime on duty-costs, public services, and real-time solution of criminal cases. After adjustment every DMUs, there are 245 efficiency values getting higher. The amount of getting higher efficiency value is almost 100% of all the DMUs. After adjustment environmental parameter, about 96% change in rank, with 24 DMUs advancement in rank, 23 DMUs degeneracy in rank, and only 2 DMUs unchanged. It shows that 24 DMUs work in unwell environment before adjustment, and 23 DMUs work in well environment before adjustment. It also shows that each police station still exist difference in working environment. Although the whole efficiency of thw police stations represent is not bad, but it still has large improvement space. Furthermore, according to Malmquist model efficiency index analysis from 2003 to 2007 data of all police stations shows that the total productivity element in Sanming First Precinct, Sanming Second Precinct, Cianjhen Precinct, Gushan Precinct, Yancheng Precinct, Zuoying Precinct and Siaogang Precinct are higher than 1, it can attributes to the increasing of technology; Sinsing and Lingya Precincts are lesser than 1, it can attributes to the decreasing of technology efficiency.
32

Systematic study of amyloid beta peptide conformations: Implications for alzheimer's disease

Jimenez, Jeffy Pilar 01 June 2005 (has links)
The amyloid beta peptide particularly the 40 and 42 amino acid residues are the responsible for plaque formation in Alzheimer's disease (AD) patients. Extra cellular plaque formation has been recognized after incessant investigations along with the formation of intracellular tau protein tangles as the hallmarks of AD. Furthermore, the plaque formation has been linked mostly as a cause of the disease and the tangles mostly as a consequence. Our investigation is focused on studying the formation of AD plaques. The amyloid beta (A[beta]) is a physiological peptide secreted from neurons under normal conditions, along with other soluble forms cleaved from the amyloid precursor protein (APP). These soluble forms of APP have neuroprotective and neurotrophic functions, while the A[beta] is considered an unwanted by-product of the APP processing. Under normal conditions there is an anabolic/catabolic equilibrium of the A[beta] peptide; therefore, it is believed that the formation of the plaque does not take place. On the other hand, the neurons' surface may play an important role in the adhesion mechanisms of the A[beta] peptide. Our experiments show that the neuron surfaces along with the media conditions may be the most important causes for progressive formation of plaques. We have incubated rigid supports (mica) and soft biomimetic substrates (lipid bilayers on top of a PEG cushion layer drafted onto a silica surface) with the three different conformations of the A[beta] peptide (monomeric, oligomeric and fibrils structures) to determine the adhesion mechanisms associated with in situ plaque formation. The soft biomimetic substrates have been assembled first by depositing and activating a thin film of silica (i.e., to create surface silanol groups). This film is then reacted with polyethylene glycol (PEG), which is a biocompatible polymer, to create a cushion-like layer that supports and allows the lipid bilayer to have high mobility. A lipid bilayer is then deposited on this soft support to reproduce a cell membrane using the Langmuir Blodgett deposition technique. The characterization of such biomimetic membranes has been studied by using Atomic Force Microscopy (AFM) in liquid environments. Our results show that these lipid bilayers are highly mobile. Additionally the structure and topography characteristics of the A[beta] conformations have been followed with atomic force microscopy (AFM). The kinetics and rates of adhesion have been measured with attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy. Our results show the progress of the plaques' formation with time where simple monomers deposit on the substrates and allow the development of oligomeric species.
33

Technical and environmental efficiency of smallholder palm oil and rubber production

Holtkamp, Anna Mareike 04 July 2016 (has links)
No description available.
34

Implementace CRM u telekomunikačního operátora / Implementation of CRM in a telecommunications service provider

Švejdová, Jana January 2011 (has links)
The diploma thesis focuses on implementation of a software solution for customer relationship management with respect to a telecommunications service provider. The whole analysis of a project implementation describes introduction of a segment called Sales Force Automation (SFA). The objective of the work is to describe all important steps during the execution of the SFA project implementation, to compare the steps to theoretical recommendations, to assess applicability of procedures with regard to users' experience and reactions during the execution and after the completion of the project and to subsequently determine recommendations for similar projects. The work is structured into a theoretical and practical part. The objective of the theoretical part is to explain the concept of CRM -- Customer Relationship Management, to introduce the recommended project plan of the CRM implementation and to present a selected product, which is Siebel CRM from Oracle. The practical part describes an already finished project implemented by a telecommunications service provider, compares the appropriate procedure to a theoretical recommendation and registers differences. Based on implications and user's reactions there were suitable and unsuitable steps determined and also procedures recommended for an easier transition to a new CRM system with regard to similar projects.
35

Vplyv prídavku vybraných olejov na zastúpenie mastných kyselín v živočíšnych tkanivách a homeostázu cholesterolu u modelového organizmu

Hnatová, Martina January 2018 (has links)
The theoretical part of my thesis is based on the general classification and characterization of dietary lipids, especially fatty acids, cholesterol and lipoprotein particles. Also, their transport and absorption mechanisms are described, as well as medical complications that are closely linked to excessive lipid consumption. One part is used for the description of lipid extractions and determination of fatty acids. The experimental part is focused on the analysis of fatty acids in samples of liver, adipose and muscle tissues of laboratory rats after the addition of palm oil, safflower oil, fish oil and Schizochytrium microalgae oil into their diets. Lyophilized tissue samples were extracted and derivatized, followed by gas chromatography fatty acid determination. The results were then statistically evaluated.
36

Fourier Multispectral Imaging

Jia, Jie 24 August 2017 (has links)
No description available.
37

Hierarchical Slow Feature Analysis on visual stimuli and top-down reconstruction

Wilbert, Niko 24 May 2012 (has links)
In dieser Dissertation wird ein Modell des visuellen Systems untersucht, basierend auf dem Prinzip des unüberwachten Langsamkeitslernens und des SFA-Algorithmus (Slow Feature Analysis). Dieses Modell wird hier für die invariante Objekterkennung und verwandte Probleme eingesetzt. Das Modell kann dabei sowohl die zu Grunde liegenden diskreten Variablen der Stimuli extrahieren (z.B. die Identität des gezeigten Objektes) als auch kontinuierliche Variablen (z.B. Position und Rotationswinkel). Dabei ist es in der Lage, mit komplizierten Transformationen umzugehen, wie beispielsweise Tiefenrotation. Die Leistungsfähigkeit des Modells wird zunächst mit Hilfe von überwachten Methoden zur Datenanalyse untersucht. Anschließend wird gezeigt, dass auch die biologisch fundierte Methode des Verstärkenden Lernens (reinforcement learning) die Ausgabedaten unseres Modells erfolgreich verwenden kann. Dies erlaubt die Anwendung des Verstärkenden Lernens auf hochdimensionale visuelle Stimuli. Im zweiten Teil der Arbeit wird versucht, das hierarchische Modell mit Top-down Prozessen zu erweitern, speziell für die Rekonstruktion von visuellen Stimuli. Dabei setzen wir die Methode der Vektorquantisierung ein und verbinden diese mit einem Verfahren zum Gradientenabstieg. Die wesentlichen Komponenten der für unsere Simulationen entwickelten Software wurden in eine quelloffene Programmbibliothek integriert, in das ``Modular toolkit for Data Processing'''' (MDP). Diese Programmkomponenten werden im letzten Teil der Dissertation vorgestellt. / This thesis examines a model of the visual system, which is based on the principle of unsupervised slowness learning and using Slow Feature Analysis (SFA). We apply this model to the task of invariant object recognition and several related problems. The model not only learns to extract the underlying discrete variables of the stimuli (e.g., identity of the shown object) but also to extract continuous variables (e.g., position and rotational angles). It is shown to be capable of dealing with complex transformations like in-depth rotation. The performance of the model is first measured with the help of supervised post-processing methods. We then show that biologically motivated methods like reinforcement learning are also capable of processing the high-level output from the model. This enables reinforcement learning to deal with high-dimensional visual stimuli. In the second part of this thesis we try to extend the model with top-down processes, centered around the task of reconstructing visual stimuli. We utilize the method of vector quantization and combine it with gradient descent. The key components of our simulation software have been integrated into an open-source software library, the Modular toolkit for Data Processing (MDP). These components are presented in the last part of the thesis.
38

Les forces de surface dynamiques pour l'investigation mécanique des surfaces molles / Dynamic surface forces for mechanical investigation of soft surfaces

Leroy, Samuel 03 December 2010 (has links)
Ce travail étudie comment la mesure des forces hydrodynamiques exercées par un liquide confiné entre une sphère et une surface d'intérêt permet de sonder à distance et sans contact les propriétés mécaniques de cette surface. Nous présentons tout d'abord le principe de cette technique originale de sonde fluide et la machine à forces de surface dynamique que nous utilisons pour mettre en œuvre ces expériences de nano-rhéologie. Puis nous nous intéressons à deux applications que nous avons plus particulièrement étudiées. D'une part, l'étude des propriétés de friction des bicouches lipidiques. Nous mettons en évidence une très faible friction mesurée sur certaines bicouches fluides et son potentiel rôle pour la bio-lubrification. D'autre part l'étude des propriétés élastiques de couche mince d'élastomère. Nous développons pour cela une théorie de l'élastohydrodynamique à géométrie sphère-plan en mode dynamique et présentons des résultats expérimentaux en très bon accord. Nous sommes capables de mesurer le module d'Young de films mince de PDMS d'épaisseur allant jusqu'à 600 nm. Enfin, nous présentons les développements instrumentaux réalisés pour optimiser les performances de la machine à forces de surfaces comme sonde fluide / This work addresses how the measurement of hydrodynamic forces of a liquid confined between a sphere and a surface of interest can lead to probe at a distance and without contact her mechanical properties. Firstly, we introduce this original technique of fluid probe and the dynamic Surface Force Apparatus used to perform these nanorheology experiments. Then, we present two applications for which the fluid probe can be of great importance. The first application is the study of friction properties of lipid bilayers. More particularly we measure very weak fluid friction coefficients on some fluid bilayers, which can be an important issue for biolubrication. The second application is the study of elastic properties of thin elastomer layers. For that we first develop an elasto-hydrodynamic theory for sphere-plan configuration in dynamic mode. Then, we present experimental results in very good agreement with this theory. We are able to measure the Young modulus of thin PDMS films of thickness as small as 600 nm. Finally, we present instrumental developments performed on the Surface Force Apparatus to optimize its potential as fluid probe
39

Nanorhéologie des liquides confimés : application à la nanomécanique des couches minces / Confined liquids nanorheology : application to thin films nanomechanics

Villey, Richard 05 December 2013 (has links)
Lorsque deux solides séparés par un liquide se rapprochent, le drainage s’accompagne de forces visqueuses normales aux parois. Si elles sont très rapprochées, de l’ordre de quelques nanomètres, les parois sont indentées par ces forces : c’est le "confinement élastique". Indenter un solide par un liquide permet de supprimer l’adhésion, qui limite la résolution en termes de module d’Young des tests classiques d’indentation par un solide, surtout pour les films supportés minces et mous, par exemple des élastomères d’épaisseur micrométrique. Or leurs propriétés, qui peuvent sensiblement différer des propriétés en volume, sont essentielles dans des domaines aussi variés que la microfluidique, l’électronique ou l’usure mécanique. Nous présentons les calculs qui relient les forces normales aux propriétés mécaniques du liquide et des parois lors d’un confinement élastique. Les résultats sont comparés à des expériences de nanorhéologie réalisées sur une machine à forces de surface très sensible. Cette sensibilité nous permet de montrer que l’effet du confinement élastique se manifeste même sans film mou déposé : cela implique que la rhéologie apparente d’un liquide confiné est toujours affectée par les déformations des parois, même très rigides.Nous montrons enfin que nous pouvons effectivement mesurer avec précision des modules d’Young autour du MPa dans des films d’élastomères de quelques centaines de nanomètres à quelques micromètres d’épaisseur. Si le module de stockage ne varie presque pas avec l’épaisseur, un module de pertes apparaît, augmentant sensiblement lorsque l’épaisseur diminue, témoignant d’une visco-élasticité que nous attribuons à la présence d’une couche interfaciale. / When two solids separated by a liquid layer are moving towards each other, the resulting drainage is associated with viscous forces normal to the walls. If these are very close to each other (several nanometers), they are indented by these forces : this is the notion of “elastic confinement”. Indenting a solid by a liquid solves the problem of adhesion, which limits the ability of classical indentationtests to provide accurate measurements on Young’s modulii. Adhesion is especially problematic for soft thin films, for example micrometric layers of elastomers, which mechanical properties can strongly differ from the bulk, but are of the highest importance in various fields such as microfluidics, electronics or mechanical wear. We present here the calculations which link the solid and liquid mechanical properties to the resulting forces in a liquid indentation test. The corresponding results are compared to nanorheology experiments using a very sensitive Surface Force Apparatus. Its sensitivity enables us to show that the elastic confinement is also measurable without any soft films, which implies that a confined liquid apparent rheology is always affected bythe deformations of even very rigid confining walls. Finally, we demonstrate that we are indeed able to measure precisely Young’s modulii in the MPa range for films as thin as several hundreds of nanometers. While the storage modulii are found to be almost independent ofthe film thicknesses, we identify the presence of loss modulii increasing with decreasing thicknesses. We attribute this unexpected viscoelastic behaviour to the presence of an interfacial layer.
40

Analisis de la relacion de la eficiencia tecnica en la infraestructura vial regional y el crecimiento economico (2007 – 2018) / Technical efficiency of road infrastructure: are regional governments being efficient?

Fernandez Cevallos, Cesar Augusto André 25 November 2020 (has links)
Infraestructura Vial; Gasto Público; Eficiencia Técnica; Análisis de Eficiencia; SFA. Road Infrastructure; Public spending; Technical Efficiency; Efficiency Analysis; SFA / La literatura menciona que la brecha en infraestructura vial puede representar una limitante al crecimiento económico, en especial, a nivel regional. El presente documento se centra en el análisis de la eficiencia técnica de la infraestructura vial en las regiones de Perú, durante el periodo comprendido entre 2007 y 2018. La metodología se compone por dos etapas. La primera tiene por objetivo determinar un índice que recoja la eficiencia del gasto público en infraestructura vial, sobre la base del análisis de eficiencia estocástica. Mediante el cual se encuentra que, un mayor gasto a nivel regional no necesariamente se refleja en una mejora en la infraestructura vial. Así, existen regiones con un menor monto destinado al gasto en carreteras, pero que cuentan con un mejor desempeño en la ejecución. En la segunda etapa, se busca asociar este indicador de eficiencia con el crecimiento de las actividades económicas a nivel regional, mediante la aplicación de Método Generalizado de Momentos. Los resultados muestran que el índice de eficiencia explica en gran parte el crecimiento de las actividades económicas. / The literature shows that the gap in road infrastructure can represent a limitation to economic growth, especially at the regional level. This article analyzes the technical efficiency of the road infrastructure in the 24 regions of Peru for the period between 2007-2018. The methodology consists of two stages. The first one aims to determine an index that collects the efficiency of public spending on road infrastructure, based on the Stochastic Efficiency Analysis. For the construction of the efficiency index, the following are identified as outputs: (i) Total National Length, (ii) Total Departmental Length and (iii) Total District Length. The main input used was spending on regional road infrastructure. The results suggest that higher spending at the regional level does not imply an improvement of the roads. There are regions with a lower amount earmarked for public spending on road infrastructure, but that have a better performance in execution. In the second stage, we seek to associate this efficiency indicator with the growth of economic activities at the regional level, through the application of Generalized Least Squares. The dependent variable was the domestic product and the explanatory variables are made up of variables such as the efficiency index, electricity consumption, hectares worked, educated EAP, mobile service lines, among others. The results confirm that the efficiency index largely explains the growth of economic activities. / Trabajo de investigación

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