• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 133
  • 45
  • 32
  • 27
  • 13
  • 8
  • 8
  • 8
  • 4
  • 4
  • 4
  • 3
  • 2
  • 1
  • 1
  • Tagged with
  • 335
  • 335
  • 180
  • 173
  • 30
  • 29
  • 28
  • 28
  • 27
  • 26
  • 26
  • 25
  • 24
  • 24
  • 21
  • 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.
171

Reform and change in police education: Examining the variations in the top-down and bottom-up structures in the process of implementation.

Kapti, Alican 08 1900 (has links)
This study examines the variations in the practice of implementation in different implementation structures using the case of police education reforms that were undertaken by the Turkish National Police (TNP) in 2001 and 2003. Differentiations and similarities in the top-down and bottom-up structures while practicing the process of implementation were investigated in this study. First, the study provides a comprehensive understanding of the process of implementation and structure of implementation. Second, the study introduces TNP education reforms and explains the reasons for the reform. Third, a quantitative approach is used to measure the success of the TNP educational reforms. Specifically, multiple regression analysis, one-way analysis of variance (ANOVA), and post hoc tests are used to clarify if police performance in the TNP has improved since the reforms. Fourth, the study uses a qualitative approach to find out how features associated with top-down or bottom up approaches were involved in the process of implementation of the educational reforms. Finally, based upon the views of the participants in the qualitative analysis, the study examines the variations in the practice of implementation between decision makers and the street level bureaucrats.
172

The Complexity of Splay Trees and Skip Lists

Adelyar, Sayed Hassan January 2008 (has links)
Magister Curationis / Binary search trees (BSTs) are important data structures which are widely used in various guises. Splay trees are a specific kind of binary search tree, one without explicit balancing. Skip lists use more space than BSTs and are related to them in terms of much of their run-time behavior. Even though binary search trees have been used for about half a century, there are still many open questions regarding their run-time performance and algorith mic complexity. In many instances, their worst-case, average-case, and best-case behaviors are unknown and need further research. Our analysis provides a basis for selecting more suitable data structures and algorithms for specific processes and applications. We contrast the empirical behavior of splay trees and skip lists with their theoretical behavior. In particular we explore when splay trees outperform skip lists and vice versa. The performance of a splay tree depends on the history of accesses to its el ements. On the other hand, the performance of a skip list depends on an indepen dent randomization of the height of links that lead to specific elements. Therefore, probabilistic methods are used to analyze the operation of splay trees and skip lists. Our main results are that splay trees are faster for sorted insertion, where AVL trees are faster for random insertion. For searching, skip lists are faster than single class top-down splay trees, but two-class and multi-class top-down splay trees can behave better than skip lists.
173

Top - Down Design eines universellen Kegelrollenlagermodells in Pro/MECHANICA

Kloninger, Paul 12 May 2011 (has links)
In dieser Präsentation wird das universelle FE-Modell eines Kegelrollenlagers vorgestellt. Mittels eines Pro/ENGINEER-Layouts, basierend auf dem Top-Down Designkonzept, kann automatisch innerhalb einer kurzen Bearbeitungszeit ein geprüftes und lauffähiges FE-Modell eines Kegelrollenlagers abgeleitet werden. Dieses Modell kann z.B. in großen Getriebemodellen eingebaut werden, um eine quasistatische Betrachtung mit korrekten Lagersteifigkeiten zu ermöglichen.
174

An fMRI Study on Context‐Dependent Processing of Natural Visual Scenes

Petzold, Antje 03 January 2006 (has links)
Visual attention can be voluntarily focused on a location or automatically attracted by salient features in a visual scene. Studies using functional Magnetic Resonance Imaging (fMRI) suggest two networks of visual attention involved in these complementary mechanisms: a dorsal frontoparietal network and a ventral frontoparietal network of visuospatial attention respectively. However, most studies so far have applied non‐natural schematic stimuli. The present study investigates visual attention in images of natural environmental scenes. Adopting previously used eye‐tracker paradigms, we study the influence of task instruction and luminance contrast modifications in pictures on both eye movements and neural activity using Eye‐Tracking and functional Magnetic Resonance Imaging simultaneously. We expect increased top‐down control of attention in a search task compared to a free viewing condition visible in enhanced neural activation in the intraparietal sulcus (IPS) as part of the dorsal frontoparietal network. Strong modifications of luminance contrast should foster bottom‐up processing activating the temporoparietal junction (TPJ) a crucial area in the ventral frontoparietal network of visual attention. Although the obtained eye‐tracking data shows the expected shift of fixations towards locations of increased luminance contrast, we do not find an influence of luminance contrast modifications on neural processing. Comparison of instructions reveals diverse results across participants possibly due to the long presentation duration of stimuli which allowed participant’s attention to wander independently of task instruction. We find bilateral activation in IPS and parahippocampal place area (PPA) as well as bilateral deactivation in the TPJ region independent of task context. This might indicate similar contributions of these areas to free viewing of and search in visual scenes. However, dissociation of target detection and attention during search by deconvolution analysis of data obtained in this study might reveal a more detailed picture of functional involvement of the IPS and TPJ region in processes of visual attention. Remarkably, results show robust activation of the PPA in both tasks, suggesting that the PPA region might not only be activated by houses and open scenes but by narrow scenes (bushes, leaves) of natural outdoor environment as well.
175

Územní studie krajiny jako nástroj řešení krajiny v územním plánování / Landscape planning study as a tool for physical planning

Masojídková, Petra January 2020 (has links)
The diploma thesis focuses on the new tool Landscape planning study for the municipality with extended competence. The main aim of this work is to find out, how Landscape planning study can be used, who can use it and how it may change the landscape. The thesis uses the case study methods of three selected municipalities with extended competence, namely Votice, Humpolec and Vodňany. The theoretical part discusses the concept of landscape and anchoring in planning activities. In next part, the thesis deals with the basic forms of tools that regulate the planning and using of landscape in Czechia, focusing mainly on spatial planning. Furthermore, the thesis deals with models that currently affect space planning, namely top-down and bottom-up models. Two basic hypotheses of the diploma thesis are set based on theoretical frameworks. There are two qualitative research methods used in the practical part of the thesis. The first method is the analysis of Landscape planning studies, second method are semi-structured interviews with selected respondents. The results of both methods show that Landscape planning study can be used only to a limited extent, mainly as an information source. However, the implementation rate of specific measures is very low now. The identified causes are the lack of...
176

Development of a Morphology-based Analysis Framework for Asphalt Pavements

Onifade, Ibrahim January 2015 (has links)
The morphology of asphalt mixtures plays a vital role in their properties and behaviour. The work in this thesis is aimed at developing a fundamental understanding of the effect of the asphalt morphology on the strength properties and deformation mechanisms for development of morphology-based analysis framework for long-term response prediction. Experimental and computational methods are used to establish the relationship between the mixture morphology and response. Micromechanical modeling is employed to understand the complex interplay between the asphalt mixture constituents resulting in strain localization and stress concentrations which are precursors to damage initiation and accumulation. Based on data from actual asphalt field cores, morphology-based material models which considers the influence of the morphology on the long-term material properties with respect to damage resistance, healing and ageing are developed. The morphology-based material models are implemented in a hot-mix asphalt (HMA) fracture mechanics framework for pavement performance prediction. The framework is able to predict top-down cracking initiation to a reasonable extent considering the variability of the input parameters. A thermodynamic based model for damage and fracture is proposed. The results from the study show that the morphology is an important factor which should be taken into consideration for determining the short- and long-term response of asphalt mixtures. Further understanding of the influence of the morphology will lead to the development of fundamental analytical techniques in design to establish the material properties and response to loads. This will reduce the empiricism associated with pavement design, reduce need for extensive calibration and validation, increase the prediction capability of pavement design tools, and advance pavement design to a new level science and engineering. / Asfaltblandningars morfologi har en avgörande betydelse för deras egenskaper och beteenden. Arbetet i denna avhandling syftar till att utveckla en grundläggande förståelse för effekten av asfaltsmorfologin för deras hållfasthetsegenskaper och deformationsmekanismer och utveckling av ramverksanalysmorfologi baserat på långsiktig förutsägelse. Experimentella beräkningsmetoder används för att fastställa sambandet mellan blandningens morfologi och respons. Mikromekanisk modellering används för att förstå det komplexa samspelet mellan asfaltmassans beståndsdelar som resulterar i spänningslokalisering och spänningskoncentrationer som är föregångare till initiering av skador och ackumulation. Morfologibaserade materialmodeller beaktar påverkan av morfologin på de långsiktiga materialegenskaperna med avseende på skademotstånd, helande samt åldrande, och är utvecklade från data hos verkliga asfaltsfältskärnor. Morfologinbaserade materialmodeller är implementerade i en varmblandad asfalt-( HMA )-brottmekanik-ramverk för förutsägelse av beläggningsprestanda. Ramverket kan i rimlig utsträckning förutspå variationen i ingångsparametrarna ’top-down’ sprickbildningsinitiering. En termodynamiskbaserat ramverk föreslås för skador och brott. Resultaten från studien visar att morfologin är en viktig faktor som bör beaktas för att bestämma respons av asfaltblandningar på kort och lång sikt. Ytterligare förståelse av inverkan av morfologin kommer att leda till utvecklingen av grundläggande analytiska tekniker i design för fastställning av materialegenskaper och belastningars respons. Detta kommer att minska empirism som förknippas med beläggningskonstruktionen, minska behovet av omfattande kalibrering och validering, öka förutsägelseförmågan av designverktyg för beläggningen, samt avancera beläggningsdesign till en ny vetenskaplig nivå och ingenjörskonst. / <p>QC 20150420</p>
177

Reliability-based Design Procedure for Flexible Pavements

Dinegdae, Yared Hailegiorgis January 2015 (has links)
Load induced top-down fatigue cracking has been recognized recently as a major distress phenomenon in asphalt pavements. This failure mode has been observed in many parts of the world, and in some regions, it was found to be more prevalent and a primary cause of pavements failure. The main factors which are identified as potential causes of top down fatigue cracking are primarily linked to age hardening, mixtures fracture resistance and unbound layers stiffness. Mechanistic Empirical analytical models, which are based on hot mix asphalt fracture mechanics (HMA-FM) and that could predict crack initiation time and propagation rate, have been developed and shown their capacity in delivering acceptable predictions. However, in these methods, the effect of age hardening and healing is not properly accounted and moreover, these models do not consider the effect of mixture morphology influence on long term pavement performance. Another drawback of these models is, as analysis tools they are not suitable to be used for pavement design purpose. The main objective of this study is to develop a reliability calibrated design framework in load resistance factor design (LRFD) format which could be implemented to design pavement sections against top down fatigue cracking. For this purpose, asphalt mixture morphology based sub-models were developed and incorporated to HMA-FM to characterize the effect of aging and degradation on fracture resistance and healing potential. These sub-models were developed empirically exploiting the observed relation that exist between mixture morphology and fracture resistance. The developed crack initiation prediction model was calibrated and validated using pavement sections that have high quality laboratory data and observed field performance history. As traffic volume was identified in having a dominant influence on predicted performance, two separate model calibration and validation studies were undertaken based on expected traffic volume. The predictions result for both model calibration and validation was found to be in an excellent agreement with the observed performance in the field. A LRFD based design framework was suggested that could be implemented to optimize pavement sections against top-down fatigue cracking. To achieve this objective, pavement sections with various design target reliabilities and functional requirements were analyzed and studied.  A simplified but efficient limit state equation was generated using a central composite design (CCD) based response surface methodology, and FORM based reliability analysis was implemented to compute reliabilities and formulate associated partial safety factors. A design example using the new partial safety factors have clearly illustrated the potential of the new method, which could be used to supplement existing design procedures. / <p>QC 20150427</p>
178

Gait analysis using computer vision for the early detection of elderly syndromes. A formal proposal

Nieto-Hidalgo, Mario 03 March 2017 (has links)
El objetivo principal de esta tesis es el desarrollo de un sistema de análisis de la marcha basado en visión que permita clasificar la marcha patológica. Este objetivo general se divide en tres subobjetivos específicos más concretos: definición formal de la marcha, especificación e implementación de un sistema de obtención de parámetros de la marcha basado en visión y clasificación de la marcha patológica. En el primer subobjetivo, definición formal de la marcha, nuestros esfuerzos consisten en obtener una definición de la marcha que incluya la visión por computador pero sin excluir otros métodos y que sea lo suficientemente abierta como para incluir todos los casos de marcha humana. La definición propuesta es la siguiente: "Gait is the anthropomorphic upright self-displacement, in an alternating stepping of two feet, with no additional fulcra, keeping at least a point of support at every time, on a horizontal or slightly inclined surface." A partir de esta definición, las variables que consideramos son tiempos y longitudes de paso y zancada, tiempos de apoyo monopodal y bipodal, velocidad, cadencia, etc... Para el segundo subobjetivo, especificación e implementación de un sistema de obtención de parámetros de la marcha basado en visión, nos centramos en el análisis de la marcha mediante visión por computador utilizando únicamente una cámara RGB, que obtenga imágenes laterales y frontales del sujeto. El algoritmo propuesto es capaz de extraer las variables de la marcha, establecidas en la definición del objetivo de especificación, con suficiente precisión, de modo que la marcha puede ser interpretada y clasificada. La decisión de limitar la infraestructura necesaria a una única cámara RGB, obedece al interés por abaratar los costes del sistema y que sea sostenible medioambientalmente, ya que no requiere de energía adicional para capturar la imagen, sino que utiliza la radiación lumínica que inunda el escenario, ya sea de forma natural o artificial. Este sistema actúa como interfaz de entrada del subobjetivo tres que son las variables de la marcha propuestas en el subobjetivo uno. Por tanto, el subobjetivo dos puede ser reemplazado por otro sistema basado en otro fenómeno como es el caso de un sistema inercial, siempre y cuando pueda proporcionar las variables definidas en el subobjetivo uno. El subobjetivo tres, clasificador de la marcha patológica, usa las variables proporcionadas por el sistema del subobjetivo dos para caracterizar la marcha y clasificarla. Mediante una serie de casos de entrenamiento, el sistema genera los modelos de marcha patológica y normal. A partir de estos modelos, el clasificador es capaz de determinar a qué modelo pertenece la entrada de parámetros de la marcha proporcionada por el subobjetivo dos. El objetivo de formalización nos ha llevado a profundizar en los aspectos conceptuales y procedimentales del conocimiento y de su creación, con la consecuencia de aportar sendas definiciones para problema y modelo, así como hallar una justificación formal, basada en la teoría de conjuntos, que confiere coherencia causal al método experimental. Además de encontrar formalmente la justificación causal del método científico, hemos podido encajar en ese marco formal los enfoques divide et vinces, model driven y top-down de resolución de problemas ingenieriles. Al tiempo que hemos encontrado que la técnica top-down de diseño es coincidente con el método científico de resolución de problemas, el método bottom-up es coherente con la implementación de prototipos, lo cual justifica la restricción de su utilización al diseño de instancias para las que ya se conoce solución.
179

Leadership in troubled waters : A case study about the role of shared leadership in transformational change when professions are getting automated

Nyberg, Elin, Smedeby, Gustaf January 2020 (has links)
To lead an organization in change is complex. Leaders today struggle with how to adapt to the digital transformational change organizations are being exposed to. Digitalization forces leaders to go beyond the traditional way of leading when professions are getting automated. This requires leaders to engage subordinates in the leadership to handle a transformational change since both subordinates and leaders are expected to adapt to technological development. Here is when the role of shared leadership becomes preferable. To investigate this complexity in the banking industry, a case study has been done. A qualitative method was used to collect and analyze the data needed to understand what leaders do to engage subordinates in the transformational change the banks are being exposed to. The results indicate that the leaders to some extent take advantage of shared leadership to involve subordinates. The findings could be applied to the shared leadership model, and the analysis shows that leaders tend to use all components to engage their subordinates, and all components are proven to be equally important. But, the analysis also shows that the banks still face challenges with being hierarchical, which inhibits the subordinates to be completely involved and engaged in the leadership. Conclusions have been made that the leaders believe they engage subordinates in transformational change, whereas not all subordinates perceive it that way.
180

Konzeption eines Umweltkennzahlensystems zur Umweltleistungsmessung für Prozesse unter Beachtung der in Unternehmen vorliegenden Rahmenbedingungen

Scheibe, Lilly January 2001 (has links)
Die vorliegende Ausgabe beschäftigt sich mit dem Thema Umweltkennzahlensysteme für die Umweltleistungsmessung. Ziel der Arbeit ist es, Unternehmen ein Hilfsmittel zur Integration von Umweltaspekten ins allgemeine Unternehmensgeschehen an die Hand zu geben. Angestrebt ist die Konzeption eines Umweltkennzahlensystems zur Umweltleistungsmessung für Prozesse. Im ersten Schritt wird ein Öko-Controlling-Modell vorgestellt und Umweltkennzahlensysteme in dieses eingeordnet. Umweltkennzahlensysteme sind der Informationsversorgung zuzurechnen. Sie dienen der Information der Informationsverwender, die mit ihrer Hilfe Planen, Steuern und Kontrollieren sollen. Es wird ein Anforderungsprofil für Umweltkennzahlensysteme erstellt, dieses Anforderungsprofil beinhaltet allgemeine Anforderungen, wie die ?Anforderungen der Informationsverwender? und ?formale und logische Anforderungen? und spezielle Anforderungen. Vorhandene Ansätze zu Umweltkennzahlensystemen werden vorgestellt und hinsichtlich des Anforderungsprofils analysiert. Aus dieser Analyse ergibt sich der Schluss, dass es kein Umweltkennzahlensystem gibt, das alle Anforderungen erfüllt. Die Auswertung der an ausgewählte Führungskräfte der SIEMENS AG verschickten Fragebögen zu Umweltkennzahlen bestätigt die gewonnene Aussage der Nicht-Existenz einer first-best-Lösung hinsichtlich eines Umweltkennzahlensystems für alle Unternehmen, da sie verdeutlicht, dass schon die Kennzahlensysteme innerhalb eines Unternehmens stark (aufgrund zu unterschiedlicher Strukturen, Ziele und Strategien) differieren. An die Auswertung der Analyse der vorhandenen Ansätze und der Fragebögen schließt sich die Entwicklung einer Vorgehensweise zur Konzeption von Umweltkennzahlensystemen in Unternehmen an, die in den Schritten Festlegung der Umweltleistung von Unternehmen, Definition der Zielebene, Festlegung und Auswahl von Kennzahlen abläuft.

Page generated in 0.0933 seconds