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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.
441

An assessment of the implication of involving local communities in biodiversity conservation : a case study of Blouberg Nature Reserve in Limpopo, South Africa

Rampheri, Mangana Berel January 2020 (has links)
Thesis (M.Sc. (Geography)) -- University of Limpopo, 2020 / This work aimed at assessing the implications of involving local communities in biodiversity conservation in Blouberg Nature Reserve (BNR) in Limpopo Province, South Africa. To achieve this objective, firstly biodiversity status before and after involving local communities in conservation initiatives was assessed using multi-temporal medium-resolution Landsat series data and species diversity indices. The results showed that there were significant variations (α = 0.05) in tree species diversity in BNR for before and after involving local communities. For example, tree species diversity was low after involving communities particularly for the years 1996 and 2019. Secondly, benefits and costs of involving local communities in biodiversity conservation as well as their investigate views, perceptions and attitudes BNR management were assessed. The study demonstrated local communities do not obtain sufficient benefits or incur numerous costs from the nature reserve. Despite this, there was considerable support for biodiversity conservation (84.2%) since household respondents still held positive attitudes towards biodiversity conservation in the reserve. For, example most of them indicated that they would report illegal activities to the authorities. However, despite lack of participation by the majority of the household respondents (89.6%) in biodiversity conservation, they demonstrated understanding of the relevance of nature conservation. In contrary, the BNR Manager stated that the local communities received benefits in the form of fuel-wood for special occasions such as funerals and bush meat sold at treasury approved tariffs during culling. However, illegal activities like poaching are still experienced in the nature reserve. Thus, the study underscores the relevance the integrating satellite data and qualitative information in assessing the ecological condition of PAs. Such information can help in biodiversity monitoring and decision-making on conservation of biodiversity. Keywords: biodiversity conservation; community-based natural resource management approach; ecological status; mapping; satellite data; spatial characterisation; species diversity; statistical analysis.
442

Uplatnění statistických metod při posuzování vybraných ukazatelů společnosti / Application of Statistical Methods in Assessing Selected Indicators of a Company

Hodulíková, Eva January 2021 (has links)
The diploma thesis deals with the application of statistical methods in assessing selected indicators of the company ABC, Ltd. This work is divided into three parts. The first part explains the terms related to financial indicators, macroeconomic indicators, regression and correlation analysis and also, this part of the work explains the matters of time series. The second part contains an analysis of the current state. Individual analyses of indicators and their predictions are performed in it. Also, there is a research concerning the influence of macroeconomic indicators on the financial performance of ABC, Ltd. In The last part of this diploma thesis, changes are proposed that should lead to the improvement of the current situation of the company.
443

Hodnocení výkonnosti AGROMORAVIA, a.s. pomocí analýzy časových řad / Assessment of the Efficiency of the AGROMORAVIA, a.s. Using Time Series Analysis

Polach, Milan January 2014 (has links)
This master‘s thesis deals with the performance evaluation AGROMORAVIA, a.s. using of classic, modern and statistical methods and subsequent formulation of own designs and their benefits to improve company performance. Based on the analysis results are compared with a competitor. In addition, selected economic indicators are subjected to statistical analysis and the result is a prediction of future development, from which derives valuable information that serves the proposals for improving the current situation of the company in the coming years. Analyses are performed for the period 2006 to 2012.
444

Posouzení finanční výkonnosti podniku pomocí analýzy časových řad / Assessing of the Financial Situation of a Company Using Time Series

Pech, Jan January 2016 (has links)
Abstract Master’s thesis about „Assessing of the financial situation of a company using time series” focuses on a detailed assessment of the economic situation of the state-owned enterprise DIAMO between years 2005–2014. The theoretical part describes methods and indicators of strategic, financial and statistical analyses, which are in the next chapter sequentially applied on the analysed company. The content of the final chapter introduce proposals of elimination of the risk areas of the state-owned enterprise, while the greatest emphasis will be applied on the issue of rising shares of receivables and liabilities to total assets and ensuring positive economic result in corporate profit. The main object of this master’s thesis is assessing financial efficiency of state-owned enterprise DIAMO, afterward identifying risk areas and introducing possible precautions, which will lead to overall greater economic health of the enterprise itself.
445

Testování nástrojů pro víceosé frézování na obráběcích centrech / Testing of Cutting Tools for Multi-Axis Machining at Machining Centres

Dvořáček, Jan January 2017 (has links)
The thesis is focused on testing of the cutting tools for machining on five axis machine tools and possibility of implementation of designed experiments in this area. The theoretical section focuses attention on analysis of specific features during five axis machining, including chip cross section and particularity of tool testing under high speed cutting conditions with consideration of dynamic stability of cutting tools. In the thesis force loading of the tool is discussed as well as its measurement process, considering force development caused by tool wear and data analysis. Description of designed experiment and its application to the area of tool testing is included as well. All theoretical predictions are followed by experimental verifying by extensive number of experimental tests, including evaluation of cutting tool condition, influence of hard coatings on cutting power of the tools, etc. For each of testing conditions are designed specific methods of processing of gathered data as well as evaluation of power of the cutting tools. Gathered data were processed by means of statistical evaluation and by statistical methods of designed experiments. The thesis contains also the extensive number of records and analysis, documented by means of light microscopy as well as electron microscopy.
446

Fiabilité et analyse de défaillance des tags RFID UHF passifs sous contraintes environnementales sévères. / Reliability and failure analysis of passive UHF RFID tags in severe environments

Taoufik, Sanae 01 February 2018 (has links)
Ces dernières années, la technologie RFID (identification par radiofréquence) s’est fortement développée dans de nombreuses applications industrielles parmi lesquelles les secteurs de l’aéronautique et l’automobile où il y a une forte demande en systèmes d’auto-identification fonctionnant dans des environnements difficiles. Dans ce contexte, l'objectif de ces travaux de thèse est d'étudier les effets du stockage thermique sur la fiabilité des tags RFID UHF passifs. Pour ce faire nous avons adopté une méthodologie homogène contribuant de façon significative à atteindre nos objectifs. La première étape de cette méthodologie consistait à choisir le tag à tester, deux types de tags Web et Tageos provenant de deux fabricants différents ont été soumis à des tests de vieillissement accélérés sous différentes températures. La deuxième étape était de définir les paramètres des tests de vieillissement et de caractériser les tags vieillis. À l'aide d'un banc de mesure dédié, la puissance réfléchie par l’ensemble des tags vieillis est mesurée après chaque phase de vieillissement en fonction de la distance entre l’antenne du tag et celle du lecteur RFID. La puissance réfléchie diminue considérablement après chaque phase de vieillissement avec différentes dynamiques de dégradation pour tous les tags vieillis. Cette dynamique de dégradation dépend du type de tag testé et de la température de test. La dernière étape de la méthodologie comportait l’analyse statistique et physique de défaillance, des différences claires dans les modes, les mécanismes et les temps de défaillance entre les tags Web et Tageos ont été observées. L’analyse physique de défaillance par microscopie optique et MEB a révélé des fissures dans les conducteurs métalliques de l'antenne pour une partie des tags vieillis, cependant pour l’autre partie des tags, aucune défaillance de l'antenne n'a été observée. Des déformations au niveau de la matrice polymère de l'ACP ont été révélées, ce qui a modifié l'adaptation d'impédance entre le RFIC et l'antenne. Des simulations en utilisant le logiciel de modélisation multi-physique COMSOL a été mise en place dans le but de reproduire les mécanismes de défaillances révélés expérimentalement soit au niveau de l’antenne ou de la RFIC. Ces travaux de thèse ont démontré l'importance d'étudier les effets du stockage en haute température sur la fiabilité des tags RFID passifs. Les défaillances sont apparues plus rapidement et les tests ont coûté considérablement moins onéreux par rapport aux autres types de tests de vieillissement accélérés. / Nowadays, RFID has strongly developed in many industrial applications, including the aeronautics and automotive sectors, where there is a strong demand for auto-identification systems operating in severe environments. In this context, the objective of this thesis is to study the effects of thermal storage on the reliability of passive UHF RFID tags. To achieve this, we adopted a consistent methodology. The first step of this methodology was to choose the tag under test. Two types of tags Web and Tageos from two different manufacturers are aged under high temperatures. The second step was to define the parameters of the aging tests and to characterize the aged tags. Using a dedicated measurement bench, the reflected power is measured after each aging phase for all tested tags to determine the power loss caused by the high temperature storage. Reflected power decrease significantly after each aging phase with different dynamics of degradation for all aged tags. This dynamics of degradation depends on the temperature test and the type of tag. The final step involved statistical and physical failure analysis. Clear differences about modes, mechanisms and failure times between Web and Tageos tags have been observed, it seems that Tageos tags are more reliable than Web tags. Failure analysis of the samples, using an optical microscope and SEM, has revealed, cracks in the antenna metallic conductors on a part of the aged tags. In another part of the tags, no failures in the antenna have been seen, but clear deformations at the polymer matrix of the ACP have been observed, thus changing the impedance matching between the RFIC and the antenna. Simulations using the COMSOL multiphysics software have been implemented in order to reproduce the experimental failure mechanisms. This thesis work has demonstrated the importance of studying the effects of high temperature storage on the reliability of passive RFID tags. Failures appeared faster and tests cost considerably less than other types of accelerated aging tests.
447

Využití anotací primární struktury pro strukturní predikci protein-ligand aktivních míst / Use of residue-level annotations for structural prediction of protein-ligand binding sites

Břicháčková, Kateřina January 2021 (has links)
The number of experimentally resolved protein structures in the Protein Data Bank has been growing fast in the last 20 years, which motivates the develop- ment of many computational tools for protein-ligand binding sites prediction. Binding sites prediction from protein 3D structure has many important applica- tions; it is an essential step in the complex process of rational drug design, it helps to infer the side-effects of drugs, it provides insight into proteins biological functions and it is helpful in many other fields, such as protein-ligand docking and molecular dynamics. As far as we know, there has not been a study that would systematically investigate general properties of known ligand binding sites on a large scale. In this thesis, we examine these properties using existing experimen- tal and predicted residue-level annotations of protein sequence and structure. We present an automated pipeline for statistical analysis of these annotations, based on hypothesis testing and effect size estimation. It is implemented in Python and it is easily extensible by user-defined annotations. The usage is demonstrated on 33 existing annotations and 4 different datasets. The practical significance of the results is tested with P2Rank prediction method. We hope that the results as well as the pipeline...
448

Development and analysis of land-use/land-cover spatio-temporal metrics in urban environments: Exploring urban growth patterns and linkages to socio-economic factors

Sapena Moll, Marta 10 January 2021 (has links)
[ES] Esta tesis aborda el desarrollo y análisis de nuevas herramientas y métodos para monitorizar y caracterizar el crecimiento urbano utilizando datos geográficos y bases de datos de usos y coberturas del suelo (LULC), así como explorar sus relaciones con factores socioeconómicos, aportando nuevas evidencias sobre el uso de los datos LULC para la caracterización urbana en diferentes niveles mediante métodos espaciales y estadísticos. En primer lugar, se compilaron e implementaron las métricas espacio-temporales más comunes dentro de una herramienta software, IndiFrag. A continuación, se presenta una metodología basada en métricas espacio-temporales y se propone un nuevo índice que cuantifica la desigualdad entre el crecimiento de la población y las zonas edificadas, para analizar y comparar los patrones de crecimiento urbano en diferentes niveles. Esto permitió una distinción de los patrones de crecimiento, además el análisis a diversos niveles contribuyó a una mejor comprensión de los patrones. En segundo lugar, se cuantificaron relaciones bidireccionales entre la estructura urbana de las ciudades y su situación socioeconómica a partir de métricas espaciales extraídas de mapas de zonas climáticas locales en 31 ciudades en Renania del Norte-Westfalia (Alemania). A partir de estos datos se cuantificaron relaciones con indicadores socioeconómicos mediante modelos de regresión lineal múltiple, explicando gran parte de su variabilidad. El método propuesto es transferible a otros conjuntos de datos, niveles y regiones. En tercer lugar, se evaluó el uso de las métricas espacio-temporales derivadas de los mapas LULC para identificar patrones espaciales de crecimiento urbano. Se utilizaron modelos de cambio de usos del suelo para simular diferentes escenarios de crecimiento urbano a largo plazo siguiendo varios patrones espaciales en diversas formas urbanas de partida. A continuación, se calcularon las métricas espacio-temporales para los escenarios simulados, se seleccionaron las más explicativas aplicando análisis discriminante y se clasificaron los patrones de crecimiento utilizando métodos estadísticos de agrupación. Por último, se identificaron relaciones empíricas entre indicadores socioeconómicos y su evolución a lo largo del tiempo con la estructura espacial de los elementos construidos y naturales en hasta 600 áreas urbanas de 32 países. Se aplicaron modelos de regresión random forest y las métricas espacio-temporales fueron capaces de explicar considerablemente la variabilidad de los indicadores socioeconómicos, confirmando que los patrones espaciales y sus cambios están vinculados a los indicadores socioeconómicos. Este trabajo contribuye a una mayor comprensión de los patrones de crecimiento urbano y amplía el conocimiento sobre las relaciones entre la estructura espacial urbana y los factores socioeconómicos. Se describen nuevos métodos para monitorizar y evaluar la sostenibilidad urbana a partir de bases de datos LULC, que podrían ser utilizadas por los investigadores, planificadores urbanos y responsables políticos para garantizar un futuro sostenible en los entornos urbanos. / [CAT] Aquesta tesi aborda el desenvolupament i l'anàlisi de noves ferramentes i mètodes per a monitorar i caracteritzar el creixement urbà utilitzant dades geogràfiques i bases de dades d'usos i cobertures del sòl (LULC), així com explorar les seues relacions amb factors socioeconòmics, i aportar noves evidències sobre la utilització de les dades LULC per a la caracterització urbana en diferents nivells mitjançant mètodes espacials i estadístics. En primer lloc, es van compilar i implementar mètriques espaciotemporals dins d'un programari, IndiFrag. A continuació, es presenta una metodologia basada en mètriques espaciotemporals i es proposa un nou índex que quantifica la desigualtat entre el creixement de la població i les zones edificades, i serveix per a analitzar i comparar els patrons de creixement urbà a diferents nivells. Això va permetre una distinció dels patrons de creixement, a més l'anàlisi a diversos nivells va contribuir a una millor comprensió dels patrons. En segon lloc, es van quantificar relacions bidireccionals entre l'estructura urbana de les ciutats i la seua situació socioeconòmica a partir de mètriques espacials extretes de mapes de zones climàtiques locals en 31 ciutats a Renània del Nord-Westfàlia (Alemanya). A partir d'aquestes dades es van quantificar relacions amb indicadors socioeconòmics mitjançant models de regressió lineal múltiple, explicant gran part de la seua variabilitat. El mètode proposat és transferible a altres conjunts de dades, nivells i regions. Seguidament, es va avaluar l'ús de les mètriques espaciotemporals derivades dels mapes LULC per a identificar patrons espacials de creixement urbà. Es van utilitzar models de canvi d'usos del sòl per a simular diferents escenaris de creixement urbà a llarg termini seguint diversos patrons espacials en diverses formes urbanes de partida. A continuació, es van calcular les mètriques espaciotemporals per als escenaris simulats, es van seleccionar les més explicatives aplicant anàlisi discriminant i es van classificar els patrons de creixement utilitzant mètodes estadístics d'agrupació. Finalment, es van identificar relacions empíriques entre indicadors socioeconòmics i la seua evolució al llarg del temps, amb l'estructura espacial dels elements construïts i naturals en fins a 600 àrees urbanes de 32 països. Es van aplicar models de regressió random forest i les mètriques van ser capaces d'explicar considerablement la variabilitat dels indicadors socioeconòmics, això confirma que els patrons espacials i els seus canvis estan vinculats als indicadors socioeconòmics. Aquest treball contribueix a una major comprensió dels patrons de creixement urbà i amplia el coneixement sobre les relacions entre l'estructura espacial urbana i els factors socioeconòmics. Es descriuen nous mètodes per a monitorar i avaluar la sostenibilitat urbana a partir de bases de dades LULC, que podrien ser utilitzades pels investigadors, planificadors urbans i responsables polítics per a garantir un futur sostenible en els entorns urbans. / [EN] This thesis addresses the development and analysis of new tools and methods for monitoring and characterizing urban growth using geo-data and land-use/land-cover (LULC) databases, as well as exploring their relationships with socio-economic factors, providing new evidences regarding the use of LULC data for urban characterization at different levels by means of spatial and statistical methods. First, the most common spatio-temporal metrics were compiled and implemented within a software tool, IndiFrag. Then, we present a methodology based on spatio-temporal metrics and propose a new index that quantifies the inequality of growth between population and built-up areas to analyze and compare urban growth patterns at different levels. This allowed for a differentiation of growing patterns, besides, the analysis at various levels contributed to a better understanding of such patterns. Second, we quantified the two-way relationship between the urban structure in cities and their socio-economic status by means of spatial metrics issued from a local climate zone map for 31 cities in North Rhine-Westphalia, Germany. Based on these data, we quantified their relationship with socio-economic indicators by means of multiple linear regression models, explaining a significant part of their variability. The proposed method is transferable to other datasets, levels, and regions. Third, we assessed the use of spatio-temporal metrics derived from LULC maps to identify urban growth spatial patterns. We applied LULC change models to simulate different long-term scenarios of urban growth following various spatial patterns on diverse baseline urban forms. Then, we computed spatio-temporal metrics for the simulated scenarios, selected the most explanatory by applying a discriminant analysis and classified the growth patterns using clustering methods. Finally, we identified empirical relationships between socio-economic indicators and their change over time with the spatial structure of the built and natural elements in up to 600 urban areas from 32 countries. We employed random forest regression models and the spatio-temporal metrics were able to explain substantially the variability of socio-economic variables. This confirms that spatial patterns and their change are linked to socio-economic indicators. This work contributes to a better understanding of urban growth patterns and improves knowledge about the relationships between urban spatial structure and socio-economic factors, providing new methods for monitoring and assessing urban sustainability by means of LULC databases, which could be used by researchers, urban planners and decision-makers to ensure the sustainable future of urban environments. / Sapena Moll, M. (2020). Development and analysis of land-use/land-cover spatio-temporal metrics in urban environments: Exploring urban growth patterns and linkages to socio-economic factors [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/158626 / TESIS
449

Statistical Analysis of Specific Secondary Circuit Effect under Fault Insertion in 22 nm FD-SOI Technology Node

McKinsey, Vince Allen January 2021 (has links)
No description available.
450

Normal forms for multidimensional databases

Lehner, Wolfgang, Albrecht, J., Wedekind, H. 02 June 2022 (has links)
In the area of online analytical processing (OLAP), the concept of multidimensional databases is receiving much popularity. Thus, a couple of different multidimensional data models were proposed from the research as well as from the commercial product side, each emphasizing different perspectives. However, very little work has been done investigating guidelines for good schema design within such a multidimensional data model. Based on a logical reconstruction of multidimensional schema design, this paper proposes two multidimensional normal forms. These normal forms define modeling constraints for summary attributes describing the cells within a multidimensional data cube and constraints to model complex dimensional structures appropriately. Multidimensional schemas compliant to these normal forms do not only ensure the validity of analytical computations on the multidimensional database, but also favor an efficient physical database design.

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