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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.
81

Integridade, disponibilidade e acurácia no posicionamento RTK e RTK em rede: Investigação no contexto da rede GNSS ativa do Estado de São Paulo

Barbosa, Eduardo de Magalhães [UNESP] 28 May 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:22:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-05-28Bitstream added on 2014-06-13T20:28:45Z : No. of bitstreams: 1 barbosa_em_me_prud.pdf: 6325120 bytes, checksum: 83ca12d41a1c8b2c08c84707b01d7e4c (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Os avanços tecnológicos nos métodos de posicionamento têm possibilitado o desenvolvimento de metodologias que viabilizam a sua utilização pelo usuário numa diversidade de aplicações. Um dos métodos de posicionamento GNSS (Global Navigation Satellite System) de grande destaque é o RTK (Real Time Kinematic) utilizando o conceito de rede de estações. Esse método utiliza a infra-estrutura de uma rede de estações de referência, para disponibilizar correções ao usuário. O conceito clássico do RTK tem como princípio básico a alta correlação dos erros provocados pela ionosfera, troposfera e órbita dos satélites na estação de referência e em uma estação próxima de interesse. No entanto, com o afastamento entre o usuário e a estação base, a eficiência do método é degradada, pois a correlação dos erros é reduzida. Mas, quando se utiliza uma rede de estações de referência, pode-se realizar a modelagem dos erros na área de abrangência da rede. Esta concepção é denominada de RTK em Rede. No que concerne a rede de estações de referência GNSS, utilizou-se a rede estabelecida no oeste do estado de São Paulo (rede GNSS-SP). O software adotado para realizar o processamento em rede foi o GPSNet na versão 2.73. Outra questão levantada foi com relação aos padrões disponíveis para a transmissão dos dados ao usuário, tais como o RTCM e CMR, mostrando as evoluções e aplicações. A questão do enlace de comunicação (link) também foi abordada, mostrando os principais tipos disponíveis, mas com ênfase na telefonia móvel que foi utilizada para transmitir os dados via internet. Foram conduzidos vários experimentos... / Technological advances in positioning methods have enabled the development of methodologies that allow its use in a great variety of applications. One method of GNSS (Global Navigation Satellite System) positioning of high performance is the RTK (Real Time Kinematic) network. This method uses the infrastructure of a network of reference stations. The original concept of RTK is the high correlation of the errors caused by ionosphere, troposphere and satellite orbit at a reference station and at a nearby station of interest. However, increasing the distance between the user and the base station, the efficiency of the method is degraded, because the error correlation is reduced. But when using a network of reference stations, a better error modeling in the area of the network is possible. This concept is the so called Network RTK. Regarding the network of GNSS reference stations, in this work the established network in the western state of São Paulo (GNSS network-SP) was used. The software adopted to perform the tests in the network was that GPSNet, version 2.73. Another issue raised during the investigation was related to the available standards for transmitting data to the user, such as CMR and RTCM. The developments and applications were presented. The issue of communication link (link) has been addressed, showing the main available types, but with emphasis on mobile phone that was the technology used to transmit data via the Internet. Several experiments were conducted in different locations to examine the integrity, availability and accuracy for RTK positioning and RTK network. The experiments performed with RTK and RTK network (using the concept of VRS (Virtual Reference Station)) showed some problems, probably related to the density of the network. Among them the accuracy, the initialization time span more than expected or even... (Complete abstract click electronic access below)
82

Evaluation of Data Integrity Methods in Storage: Oracle Database

Posse, Oliver, Tomanović, Ognjen January 2015 (has links)
Context. It is very common today that e-commerce systems store sensitiveclient information. The database administrators of these typesof systems have access to this sensitive client information and are ableto manipulate it. Therefore, data integrity is of core importance inthese systems and methods to detect fraudulent behavior need to beimplemented. Objectives. The objective of this thesis is to implement and evaluatethe features and performance impact of different methods for achievingdata integrity in a database, Oracle to be more exact.Methods. Five methods for achieving data integrity were tested.The methods were tested in a controlled environment. Three of themwas tested and performance evaluated by a tool emulating a real lifee-commerce scenario. The focus of this thesis is to evaluate the performanceimpact and the fraud detection ability of the implementedmethods. Results. This paper evaluates traditional Digital signature, Linkedtimestamping applied to a Merkle hash tree and Auditing performanceimpact and feature impact wise. Two more methods were implementedand tested in a controlled environment, Merkle hash tree and Digitalwatermarking. We showed results from the empirical analysis, dataverification and transaction performance. In our evaluation we provedour hypothesis that traditional Digital signature is faster than Linkedtimestamping. Conclusions. In this thesis we conclude that when choosing a dataintegrity method to implement it is of great importance to know whichtype of operation is more frequently used. Our experiments show thatthe Digital signature method performed better than Linked timestampingand Auditing. Our experiments did also conclude that applicationof Digital signature, Linked timestamping and Auditing decreasedthe performance by 4%, 12% and 27% respectively, which is arelatively small price to pay for data integrity.
83

Bioaktivní peptidy - nadějná složka kosmetických produktů. / Bioactive peptides as a component of anti-aging cosmetics

Jatzová, Katarína January 2012 (has links)
Ageing is a natural part of every human life cycle. During ageing there are lots of changes in the organism. One of the main pillars of the cosmetics industry is the development of active compounds that are fighting signs of skin ageing. The components as bioactive peptides are considered to be promising anti-ageing products, mainly because of the possibility to precisely define their chemical structure and therefore achieve more effective biological targeting. One of the signs of skin ageing is the weakening of the connections between epidermal cells and the extracellular matrix, decreasing expression of adhesion molecules and molecular components of dermo-epidermal connection. The most abundant adhesive receptors in the skin are integrins. Their ligands are extracellular matrix molecules, e. g. laminin or fibronectin. The minimal recognition sequence of integrins receptors is the amino acid motif arginine- glycine- aspartic acid (RGD). This sequence is also very interesting in terms of cosmetic applications because it provides the ability to create new and effective bioactive peptides. The subject of present work is basic safety testing of four peptides with RGD motif. A sequence of three peptides was modified by addition of glycine amino acids, or alanine. The expected effect was to improve interaction with integrin receptors. In each of the sample, levels of endotoxin was determined in order to exclude any possible interfering effects on the viability of cells. Subsequently, in NIH3T3 mouse fibroblasts viability was monitored by MTT assay and morphology. The quantity of obtained protein had been determined to increase data interpretation relevance.
84

Možnosti zvyšování výkonnosti GNSS pro zajištění provozu RNP-RNAV / Ways of Improving GNSS Performance for RNP-RNAV Operations

Kvíčala, Aleš January 2008 (has links)
The goal of this thesis is to analyze current requirements of navigation system RNP RNAV. Particularly is behaving about estimation current ways and description of future improving GNSS performance. In submitted thesis is describes present evolution of area navigation and required navigation performance RNP. The next part deals with the common access how to raise the performance parameters, their estimation and also description how it'll be solve in future systems.
85

Tension between the right to external self-determination and territorial integrity in Africa : Somaliland as a case study

Farah, Mohamed D. January 2010 (has links)
The concept of nation-state was imposed on the African continent. The African state is not the product of natural growth of the African peoples from tribal societies to nations.The colonial masters brought to Africa a nation-state that was based on legal and philosophical principles evolved elsewhere in the world.These principles became the measurements against which any nation should be tested to qualify for statehood. Accordingly, African borders were drawn. The two conflicting principles of self-determination and territorial integrity are amongst those principles. The former entails the right to peoples to determine their destination both politically and economically. The latter protects countries from fragmentation. The irony is how to ensure that all peoples achieve their right to self-determination and at the same time, national states are protected from dissolution. / Thesis (LLM (Human Rights and Democratisation in Africa)) -- University of Pretoria, 2010. / A dissertation submitted to the Faculty of Law University of Pretoria, in partial fulfilment of the requirements for the degree Masters of Law (LLM in Human Rights and Democratisation in Africa). Prepared under the supervision of Dr. Magnus Killander of the Faculty of Law, University of Pretoria, Pretoria, South Africa. 2010. / http://www.chr.up.ac.za/ / Centre for Human Rights / LLM
86

Microcompartmentalization of Cell Wall Integrity Signaling in Kluyveromyces lactis

Meyer, Sascha 24 September 2014 (has links)
The yeast cell wall provides a first barrier to the environment, confers shape and stability to the cells, and serves as a model for fungal cell wall biosynthesis and function in general. During normal growth, during mating and upon cell surface stress, new wall synthesis is induced by a conserved signaling cascade, the cell wall integrity (CWI) pathway. A signal is initiated by plasma membrane-spanning sensors and transduced through a mitogen-activated protein kinase (MAPK) cascade, which ultimately activates a transcriptional activator, Rlm1. The first part of this thesis analyses the role of this MADS-box transcription factor in the milk yeast Kluyveromyces lactis, which has not been investigated, until now. With respect to the distribution of the upstream CWI sensors, evidence for the existence of a special plasma membrane microcompartment, generally referred to as eisosomes, in the milk yeast is provided in the second part of the thesis. Regarding the transcription factor KlRlm1, its impact on the physiology of K. lactis seems to be different from its homolog in Saccharomyces cerevisiae, ScRlm1, although it clearly acts in CWI signaling, too. Thus, in contrast to the Scrlm1 mutant, a Klrlm1 deletion is sensitive, rather than hyper-resistant, towards Congo red and Calcofluor white, typical stress agents used in cell wall research. Data on cross-complementation of the two genes in the respective heterologous yeast indicate that KlRlm1 and ScRlm1 each perform their optimal function only in the native host.To investigate the impact of a Klrlm1 deletion on the transcriptional profile of K. lactis, data from total mRNA sequencing were analyzed in comparison to a wild-type strain. Many of the genes identified did not correspond to known Rlm1 target genes in S. cerevisiae, but many relate to other stress responses (e.g. KlGRE1, KlFMP16, KLLA0C05324g, KLLA0F18766g, KlUGX2) and to chitin synthesis (KlCHS1, KlSKT5 and KlYEA1), both probably connected to cell wall composition. The functions of a large group of KlRlm1 dependent genes identified here are yet uncharacterized or lack homologs in S. cerevisiae. The plasma membrane of fungi is a specialized organelle, which is ordered into several lateral domains, which we define as microcompartments, since each is composed of a special combination of proteins in their lipid environment. Such microcompartments are believed to control a variety of signaling (and transport) processes in all sorts of eukaryotic cells. Microcompartmentalization is also observed in the yeast plasma membrane, e.g. displayed by the CWI sensors in K. lactis, as shown in this thesis. Since distribution of the latter sensors is reminiscent of that of eisosomes, it was also investigated by live-cell fluorescence microscopy, how KlPil1, KlLsp1 and KlSur7 (all homologs of eisosomal proteins in S. cerevisiae) are distributed. Since they form the typical membrane patches, which are not present in deletion mutants of KlPIL1, the major structural component of eisosomes, one can conclude, that eisosomal microcompartments form in K. lactis and are composed similar to their counterparts in S. cerevisiae. The CWI sensors are excluded from these structures and form their separate microcompartments. The exact physiological function of eisosomes in fungi is still a matter of debate and future studies in K. lactis may help to address this role.
87

The development of an ecological integrity index for quaternary catchments in South Africa

Van Dam, Carien Engela 28 February 2012 (has links)
MSc., Faculty of Science, University of Witwatersrand, 2011 / A multifactor ecological integrity index, focusing on freshwater ecosystems on a quaternary catchment scale, can be of great benefit to conservation planning. No ecological integrity index has previously been developed for South African quaternary catchments. In this study an index was developed based on three environmental surrogates: land cover, river integrity and fish species conservation status, with the intention of identifying quaternary catchments of highest conservation concern. By developing such an index, the aim was to provide a general indication of the degree to which catchments have been transformed from a natural environment to a human altered environment, thereby identifying catchments most in need of conservation. For the three available datasets, indices were developed using a five category point-scoring system. A score of one indicates a completely degraded environment and a score of five indicates a pristine environment. The original land cover data consisted of 49 different land cover types which were reduced to five land cover transformation scores. Available river integrity data already existed in five categories and a numerical score of one to five was applied to each category. Fish species conservation status was scored according to the IUCN red data list classifications on a similar basis. Subsequently, a weighted mean score expressed as a percentage was calculated for the three indices for each quaternary catchment. These indices indicate the degree of change/transformation from a natural system (100%) to a largely degraded system (20%). Ultimately, an ecological integrity index was calculated as a mean value of the three related but independent indices. However, the results of the developed ecological integrity index were not representative of real world conditions. This is largely attributed to the lack of complete data found in two out of the three datasets used in the study. Some of the main limitations encountered were the lack of river segment definitions within each catchment and the incomplete and un-systematic collected fish species data records. The land cover data, on the contrary, was of high definition and high standard. It is recommended that in the interim, the developed land transformation index, based on a detailed analysis of land cover, be used as an indicator index of ecological integrity of catchments
88

Disturbance and its effects on archaeological significance and integrity

Kennedy, Jason Alan 06 August 2011 (has links)
Significance and integrity are key concepts for archaeology, and how they are judged is determined by an archaeologist’s perceptions of disturbance. This thesis explicitly considers these concepts and how they relate to evolutionary theory and National Register eligibility. A site with known disturbance was chosen to determine whether it could be judged significant assuming that there was no disturbance. Controlled surface collection, magnetometer survey, excavation and landowner interview data were used to determine whether what made the site significant had been lost due to disturbance. The results indicate that the co-mingling of occupations in the plow zone normally would have prevented the site from being determined eligible. However, because of the clusters of Gulf Formational-period diagnostics and intact Early Archaic midden, the site was determined significant. If future work were to be performed, occupation-based work focusing on the artifact clusters and the Archaic midden is recommended.
89

Determinants Of Turkish Police Officers' Perception Of Integrity: Impact Of Organizational Culture

Kucukuysal, Bahadir 01 January 2008 (has links)
The purpose of this research was to examine the influence of police organizational culture on officers' perception of integrity in the Turkish National Police (TNP). Adopting an organizational rather than an individualistic perspective, this study focused on police organizational culture to investigate the causes of integrity problems in the TNP. While focusing on police organizational culture, this study also aimed to determine to what extent officers' perceptions of integrity are influenced by personal and occupational attributes such as age, gender, rank, income, educational level, years of employment, and assignment type. The research was conducted in Turkey's two largest cities, Istanbul and Ankara, as well as the largest city of southeastern Turkey, Diyarbakir. Three hundred officers, consisting of 200 regular police officers and 100 ranked officers, were selected from each city, making a sample size of 900 in total. With a total of 507 respondents, after eliminating cases with missing values, the study achieved a 57% response rate. Structural equation modeling was used to test the hypothesized relationships, since it is the most appropriate statistical method for testing hypotheses based on relations among latent and observed variables. This method enabled the researcher to measure the perception of police integrity and the perception of police organizational culture with their multiple indicators, providing rigorous measurements for both constructs. The results of the statistical analysis supported the research hypothesis. The findings showed that officers' perception of police organizational culture negatively influenced their perception of integrity. It was also found that officers' age and educational level also had a statistically significant influence on their perception of integrity.
90

Faculty Perceptions of Undergraduate Academic Dishonesty

Saddlemire, Marie T. 04 April 2005 (has links)
No description available.

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