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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

Hodnotová orientace studentů Teologické fakulty Jihočeské univerzity v Českých Budějovicích ve volném čase / The value orientation of students of the Faculty of Theology the University of South Bohemia in Budweis in their leisure time

BEREŠOVÁ, Jana January 2015 (has links)
This thesis deals with the value orientation of students of the Faculty of Theology the University of South Bohemia in Budweis in their leisure time. Firstly, there are explained the basic concepts, which are followed by a detailed overview of particular value concepts to their philosophical, sociological, pedagogical and psychological perspective. Furthermore, the classification values of the selected authors, roles of values and their importance in human life and society are presented in this thesis. Last but not least is this thesis focused on the researches of value orientations in both Czech and foreign literature. There is a chapter elaborated about the leisure time, its concepts, definitions of selected authors, functions of leisure time and its role in socioscientific contexts at the conclusion of the theory part. The main aim of the research is to describe and analyze the value orientation of students of the Faculty of Theology the University of South Bohemia in Budweis in their leisure time. The data obtained from a non-standardized questionnaire will be compared by gender, the age of students and their years of study at the Theological Faculty. Eventually, will be the evaluation and recomendation made for the use in practise.
82

Avaliação de uma nova técnica (TF-Test Modified) destinada ao diagnóstico de parasitoses intestinais em amostras fecais / Evaluation of a new technique (TF-Test Modified) intended for the diagnosis of intestinal parasites in fecal samples

Carvalho, Juliana Barboza, 1986- 23 August 2018 (has links)
Orientadores: Jancarlo Ferreira Gomes, Alexandre Xavier Falcão / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-23T15:19:46Z (GMT). No. of bitstreams: 1 Carvalho_JulianaBarboza_M.pdf: 1818938 bytes, checksum: d44ab358d0482575e52d1f77a3f4c07b (MD5) Previous issue date: 2013 / Resumo: As parasitoses intestinais são altamente prevalentes no mundo, estando entre as maiores causadoras de doenças e óbitos em seres humanos. Atualmente, o diagnóstico laboratorial destas parasitoses é realizado por meio de procedimentos técnicos manuais, desenvolvidos na sua grande maioria há décadas, o que justifica a aplicabilidade de técnicas mais sensíveis e práticas para esta finalidade, visando obter resultados eficientes, especialmente em programas governamentais direcionados à Saúde Pública. Sendo assim, o objetivo do projeto foi de avaliar e validar uma nova técnica parasitológica, denominada TF-Test Modified, em comparação com três técnicas parasitológicas convencionais consagradas pela literatura: TF-Test Conventional; Rugai, Mattos e Brisola; e Kato-Katz/Helm-Test. As etapas do trabalho consistiram em realizar coleta de material fecal de 457 indivíduos localizados em regiões endêmicas para parasitoses no município de Campinas, SP; no processamento laboratorial de 1.828 exames; no diagnóstico de 14 espécies parasitárias; e na análise estatística qualitativa de resultados de maneira abrangente. Dentre as espécies parasitárias encontradas, helmintos e protozoários intestinais foram detectados em 42,23% de indivíduos pela técnica de TF-Test Modified, ante 36,76% por TF-Test Conventional, 5,03% por Kato-Katz/Helm-Test, e 4,16% por Rugai, Mattos e Brisola. Destes casos, 54,40% de infecção simples dos indivíduos demonstrou serem portadores de monoparasitismo. A nova técnica parasitológica de TF-Test Modified, quando comparada com as demais técnicas, apresentou alto valor de infecção, como exemplo para dupla, tripla e múltipla, de maneira a perfazer um total de 98,37% de infecções. Ademais, a nova técnica apresentou índice Kappa com grau de concordância Quase Perfeito em todos os parâmetros avaliados com estimativa de 95% (P<0,05), permitiu encontrar com alta eficiência diagnóstica todas as espécies parasitárias estudadas, mostrou um notável diagnóstico verdadeiro, especialmente quando analisada comparativamente com as outras três técnicas convencionais. O atual estudo permitiu concluir que a técnica de TF-Test Modified pode ser utilizada de forma abrangente no diagnóstico qualitativo de protozoários e helmintos intestinais de humanos. O ganho de sensibilidade diagnóstica proporcionada por esta nova técnica deverá ser de estimável contribuição para o diagnóstico individual laboratorial, inquéritos populacionais e controle das parasitoses intestinais, de modo a repercutir em contribuição social / Abstract: Intestinal parasites are highly prevalent worldwide and is among the largest cause of illness and death in humans. Currently, the laboratory diagnosis of these parasites is accomplished through technical procedures manuals, developed mostly for decades, justifying the applicability of more sensitive techniques and practices for this purpose, to obtain effective results, especially in government programs aimed at Public Health. Thus, the objective of the project was to evaluate and validate a new technique parasite, called TF-Test Modified, compared with three conventional parasitological techniques enshrined in literature: TF-Test Conventional; Rugai, Mattos and Brisola, and Kato-Katz / Helm-Test. The steps of the work consisted of conducting a collection of fecal samples from 457 individuals located in regions endemic for parasitic infections in Campinas, SP, in laboratory processing of 1,828 examinations, the diagnosis of 14 parasitic species, and the qualitative statistical analysis of results so comprehensive. Among the species found parasitic, helminths and intestinal protozoa were detected in 42,23% of subjects using the technique of TF-Test Modified, against 36,76% by TF-Test Conventional, 5,03% by Kato-Katz/Helm-Test, and 4,16% Rugai, Mattos and Brisola. Of these cases, 54,40% of single infections of individuals were shown to be carriers of monoparasitism. The new technique parasitological TF-Test Modified compared to other techniques of infection showed a high value, for example double, triple and multiple so as to make a total of 98,37% infections . Moreover, the new technique presented Kappa index level of agreement with Almost Perfect in all parameters with estimated 95% (P <0.05), allowed to meet with high diagnostic efficiency all parasitic species studied showed remarkable true diagnosis, especially when viewed in comparison with other three conventional techniques. The current study showed that the technique TF-Test Modified can be used comprehensively in qualitative diagnosis of intestinal protozoa and helminths of humans. The gain in diagnostic sensitivity afforded by this new technique should be estimable contribution to the individual diagnostic laboratory, population surveys and control of intestinal parasites, in order to reflect on social contribution / Mestrado / Parasitologia / Mestra em Parasitologia
83

Extraction automatique de caractéristiques malveillantes et méthode de détection de malware dans un environnement réel / Automatic extraction of malicious features and method for detecting malware in a real environment

Angoustures, Mark 14 December 2018 (has links)
Pour faire face au volume considérable de logiciels malveillants, les chercheurs en sécurité ont développé des outils dynamiques automatiques d’analyse de malware comme la Sandbox Cuckoo. Ces types d’analyse sont partiellement automatiques et nécessite l’intervention d’un expert humain en sécurité pour détecter et extraire les comportements suspicieux. Afin d’éviter ce travail fastidieux, nous proposons une méthodologie pour extraire automatiquement des comportements dangereux données par les Sandbox. Tout d’abord, nous générons des rapports d’activités provenant des malware depuis la Sandbox Cuckoo. Puis, nous regroupons les malware faisant partie d’une même famille grâce à l’algorithme Avclass. Cet algorithme agrège les labels de malware donnés par VirusTotal. Nous pondérons alors par la méthode TF-IDF les comportements les plus singuliers de chaque famille de malware obtenue précédemment. Enfin, nous agrégeons les familles de malware ayant des comportements similaires par la méthode LSA.De plus, nous détaillons une méthode pour détecter des malware à partir du même type de comportements trouvés précédemment. Comme cette détection est réalisée en environnement réel, nous avons développé des sondes capables de générer des traces de comportements de programmes en exécution de façon continue. A partir de ces traces obtenues, nous construisons un graphe qui représente l’arbre des programmes en exécution avec leurs comportements. Ce graphe est mis à jour de manière incrémentale du fait de la génération de nouvelles traces. Pour mesurer la dangerosité des programmes, nous exécutons l’algorithme PageRank thématique sur ce graphe dès que celui-ci est mis à jour. L’algorithme donne un classement de dangerosité des processus en fonction de leurs comportements suspicieux. Ces scores sont ensuite reportés sur une série temporelle pour visualiser l’évolution de ce score de dangerosité pour chaque programme. Pour finir, nous avons développé plusieurs indicateurs d’alertes de programmes dangereux en exécution sur le système. / To cope with the large volume of malware, researchers have developed automatic dynamic tools for the analysis of malware like the Cuckoo sandbox. This analysis is partially automatic because it requires the intervention of a human expert in security to detect and extract suspicious behaviour. In order to avoid this tedious work, we propose a methodology to automatically extract dangerous behaviors. First of all, we generate activity reports from malware from the sandbox Cuckoo. Then, we group malware that are part of the same family using the Avclass algorithm. We then weight the the most singular behaviors of each malware family obtained previously. Finally, we aggregate malware families with similar behaviors by the LSA method.In addition, we detail a method to detect malware from the same type of behaviors found previously. Since this detection isperformed in real environment, we have developed probes capable of generating traces of program behaviours in continuous execution. From these traces obtained, we let’s build a graph that represents the tree of programs in execution with their behaviors. This graph is updated incrementally because the generation of new traces. To measure the dangerousness of programs, we execute the personalized PageRank algorithm on this graph as soon as it is updated. The algorithm gives a dangerousness ranking processes according to their suspicious behaviour. These scores are then reported on a time series to visualize the evolution of this dangerousness score for each program. Finally, we have developed several alert indicators of dangerous programs in execution on the system.
84

Μελέτη του ρόλου του μεταγραφικού παράγοντα COUP-TF στη διαφοροποίηση πρόδρομων κυττάρων σκελετικού μυός

Καρπαθάκη, Αγγελική-Φαίδρα 06 December 2013 (has links)
Ο μεταγραφικός παράγοντας COUP-TF είναι ένας ορφανός πυρηνικός υποδοχέας, ο οποίος είναι πολύ σημαντικός κατά την εμβρυική ανάπτυξη. Στην παρούσα εργασία επιχειρήθηκε η μελέτη του φυσιολογικού ρόλου του COUP-TFII των θηλαστικών κατά την αναγέννηση του σκελετικού μυός, χρησιμοποιώντας ως μοντέλο διαφοροποίησης τη μυοβλαστική σειρά ποντικού C2C12, που προέρχεται από ενήλικα βλαστικά κύτταρα του ίδιου μυός. Ο mCOUP-TFII εμπλέκεται στη ρύθμιση της ανάπτυξης του καρδιαγγειακού συστήματος, της μυογένεσης και άλλων αναπτυξιακών διαδικασιών. Έχει δειχθεί ότι αναστέλλει τη διαφοροποίηση των μυοβλαστών C2C12 σε μυοσωλήνες, κυρίως μέσω καταστολής της έκφρασης των μεταγραφικών παραγόντων μυογένεσης MyoD και Myogenin. Επίσης, η έκφρασή του στους μυοβλάστες C2C12 καταστέλλεται με την έναρξη της διαφοροποίησης. Αδημοσίευτα αποτελέσματα του εργαστηρίου μας, έχουν δείξει ότι μέσω εναλλακτικού ματίσματος στο mRNA του PlCOUP-TF του αχινού προκύπτουν δύο ισομορφές του υποδοχέα που διαφέρουν ως προς ένα εξώνιο 21 αμινοξέων στην DBD. H μικρή ισομορφή είναι λειτουργικός μεταγραφικός παράγοντας και δρα ως ομοδιμερές, ενώ η μεγάλη ισομορφή και τα ετεροδιμερή των δυο ισομορφών εμφανίζουν αδυναμία πρόσδεσης στο DNA. Με αυτόν τον τρόπο, η μεγάλη ισομορφή ρυθμίζει την ποσότητα του λειτουργικού μεταγραφικού παράγοντα, δρώντας ως επικρατής κατασταλτική πρωτεΐνη. Αρχικά, μελετήθηκαν οι ιδιότητες πρόσδεσης του mCOUP-TFII και η δυνατότητα σχηματισμού ετεροδιμερών με τη μεγάλη ισομορφή του PlCOUP-TF (L.I.) μέσω δοκιμής in vitro πρόσδεσης (EMSA), δεδομένης της ικανότητας ετεροδιμερισμού του hCOUP-TFI με την ομόλογη πρωτεΐνη του αχινού. Βρέθηκε ότι ο mCOUP-TFII δύναται να προσδεθεί στο στοιχείο απόκρισης C1R με τη μορφή ομοδιμερών και έχει ικανότητα ετεροδιμερισμού με τη PlCOUP-TF L.I. Τα ομοδιμερή του mCOUP-TFII εμφάνιζαν μειούμενη πρόσδεση στο DNA, όσο αυξανόταν ο λόγος PlCOUP-TF L.I./mCOUP-TFII. Ο απώτερος στόχος της έρευνας ήταν η μελέτη του ρόλου του mCOUP-TFII στη μυϊκή διαφοροποίηση, μέσω της υπερέκφρασης της επικρατούς κατασταλτικής PlCOUP-TF L.I. σε καλλιέργειες κυττάρων C2C12. Η αρχική μας υπόθεση ήταν ότι η PlCOUP-TF L.I. δύναται να δράσει ως επικρατής κατασταλτική ισομορφή του mCOUP-TFII, μέσω σχηματισμού μη λειτουργικού ετεροδιμερούς μαζί του. Σε αυτή την περίπτωση, θα αναμενόταν η PlCOUP-TF L.I. να καταστείλει τη δράση του ενδογενούς mCOUP-TFII των κυττάρων C2C12, με αποτέλεσμα την επαγωγή της διαφοροποίησης των μυοβλαστών. Αντιθέτως, η υπερέκφραση του mCOUP-TFII, θα αναμενόταν να συντελέσει στη διατήρηση της αδιαφοροποίητης κατάστασης των μυοβλαστών. Δεν παρατηρήθηκε διαφορά στις δράσεις των δυο COUP-TFs, ωστόσο, από τα πειράματα αυτά δεν μπορεί να εξαχθεί κάποιο ασφαλές συμπέρασμα αναφορικά με το ρόλο του mCOUP-TFII στη διαφοροποίηση των μυοβλαστών και τη δυνατότητα in vivo αλληλεπίδρασης μεταξύ των δυο υποδοχέων. / The transcription factor COUP-TF is an orphan nuclear receptor, which is very important during embryonic development. In the present dissertation, we attempted to study the physiological role of mammalian COUP-TFII during skeletal muscle regeneration, by use of the myoblast cell line C2C12, which originates from adult stem cells of skeletal muscle, as a model system of cell differentiation. mCOUP-TFII is involved in the regulation of cardiovascular system development, myogenesis and other developmental processes. It has been shown to inhibit the differentiation of C2C12 myoblasts to myotubes, mainly through suppression of the myogenic regulatory factors MyoD and Myogenin gene expression. Moreover, its expression in C2C12 myoblasts is suppressed at the onset of differentiation. Alternative splicing of the sea urchin PlCOUP-TF mRNA results in two isoforms, which differ by a 21 aa insertion in the DBD (unpublished data). The small isoform is a functional transcription factor that acts as a homodimer, while the large isoform and the heterodimers of the two isoforms fail to bind DNA. In this way, the large isoform regulates quantitatively the functional transcription factor, acting as dominant negative protein. Initially, by using in vitro binding assays (EMSA), we studied the binding properties of mCOUP-TFII and the possibility of forming heterodimers with the large isoform of PlCOUP-TF (L.I.), provided that hCOUP-TFI has been reported to be able to heterodimerize with the sea urchin homologue. We found that mCOUP-TFII is capable of binding the C1R response element as a homodimer and of forming heterodimers with PlCOUP-TF L.I. The binding of mCOUP-TFII homodimers has been shown to reduce as the ratio PlCOUP-TF L.I./mCOUP-TFII increases. The ultimate goal of this research, was the study of the role of mCOUP-TFII in muscle differentiation via overexpression of the dominant negative PlCOUP-TF L.I. in C2C12 cell cultures. Our initial assumption was that PlCOUP-TF L.I. is capable of acting as a dominant negative isoform of mCOUP-TFII, by forming non functional heterodimers with it. In this case, PlCOUP-TF L.I. would be expected to suppress the action of endogenous mCOUP-TFII in C2C12 cells. In contrast, overexpression of mCOUP-TFII would be expected to contribute to the maintenance of myoblasts in an undifferentiated state. We did not observe any difference in the actions of the two COUP-TFs, however, we cannot report any result regarding either the role of mCOUP-TFII in myoblast differentiation or the ability of in vivo interaction between these receptors.
85

Sequence and Structural Determinants of Specificity Differences between Paralogous Transcription Factors

Shen, Ning January 2016 (has links)
<p>Transcription factors (TFs) control the temporal and spatial expression of target genes by interacting with DNA in a sequence-specific manner. Recent advances in high throughput experiments that measure TF-DNA interactions in vitro and in vivo have facilitated the identification of DNA binding sites for thousands of TFs. However, it remains unclear how each individual TF achieves its specificity, especially in the case of paralogous TFs that recognize distinct target genomic sites despite sharing very similar DNA binding motifs. In my work, I used a combination of high throughput in vitro protein-DNA binding assays and machine-learning algorithms to characterize and model the binding specificity of 11 paralogous TFs from 4 distinct structural families. My work proves that even very closely related paralogous TFs, with indistinguishable DNA binding motifs, oftentimes exhibit differential binding specificity for their genomic target sites, especially for sites with moderate binding affinity. Importantly, the differences I identify in vitro and through computational modeling help explain, at least in part, the differential in vivo genomic targeting by paralogous TFs. Future work will focus on in vivo factors that might also be important for specificity differences between paralogous TFs, such as DNA methylation, interactions with protein cofactors, or the chromatin environment. In this larger context, my work emphasizes the importance of intrinsic DNA binding specificity in targeting of paralogous TFs to the genome.</p> / Dissertation
86

A distributed instrumentation system for the acquisition of rich, multi-dimensional datasets from railway vehicles

Stewart, Edward James Charles January 2012 (has links)
This thesis presents work carried out over a number of years within the field of railway vehicle instrumentation. The railway industry is currently moving to be more heavily “data driven”. This means that railway organisations are putting policies into place whereby decisions have to be justified based on recorded and citable data. To achieve this, the railway industry is increasingly turning to greater and greater levels of instrumentation to deliver the data on which to base these decisions. This thesis considers not only this increased requirement for data, but the frameworks and systems that must be put into place in order first to obtain it, and then to extract useful information from it. In particular the author considers the issue of contextualisation of data, where multiple datastreams may be used to provide context for, or allow more accurate and beneficial interpretation of each other in order to support better decision making. In order to obtain this data, the thesis explores, through a series of case studies, a number of options for different instrumentation system architectures. This culminates in the development of a distributed system of embedded processors arranged in an extensible modular framework to provide a rich, coherent and integrated dataset which can then be processed contextually to yield a better understanding of the railway system.
87

A generic fault detection and diagnosis approach for pneumatic and electric driven railway assets

Bai, Hao January 2010 (has links)
The railway assets studied in this project, are those widely distributed pieces of equipment that are critical to the dependable operation of the railway system. A failed asset is likely to cause significant delay to rail services, and may even place the system into an unsafe state. A generic fault detection and diagnosis (FDD) solution for a number of railway assets of different types is therefore desired. In this thesis, five assets, namely the pneumatic train door, point machine and train-stop, the electric point machine and the electro-hydraulic level crossing barrier, are considered as case studies. Based on their common dynamic characteristics, these assets are also known as Single Throw Mechanical Equipments (STMEs). A generic FDD method is proposed for these STMEs, which consists of sensor inputs and pre-processing, fault detection processes and fault diagnosis processes. A generic model, composed of a series of sub-models, is constructed to describe the behaviour of each asset. The results of fault detection approaches indicate that the proposed method has good performance and is generically applicable to the five assets. Two fault diagnosis methods using fault model and residual analysis are proposed and the fault model based fault diagnosis is preliminarily approached. Finally, a new three level architecture for railway condition monitoring is discussed for practical applications.
88

Development of semantic data models to support data interoperability in the rail industry

Tutcher, Jonathan January 2016 (has links)
Railways are large, complex systems that comprise many heterogeneous subsystems and parts. As the railway industry continues to enjoy increasing passenger and freight custom, ways of deriving greater value from the knowledge within these subsystems are increasingly sought. Interfaces to and between systems are rare, making data sharing and analysis difficult. Semantic data modelling provides a method of integrating data from disparate sources by encoding knowledge about a problem domain or world into machine-interpretable logic and using this knowledge to encode and infer data context and meaning. The uptake of this technique in the Semantic Web and Linked Data movements in recent years has provided a mature set of techniques and toolsets for designing and implementing ontologies and linked data applications. This thesis demonstrates ways in which semantic data models and OWL ontologies can be used to foster data exchange across the railway industry. It sets out a novel methodology for the creation of industrial semantic models, and presents a new set of railway domain ontologies to facilitate integration of infrastructure-centric railway data. Finally, the design and implementation of two prototype systems is described, each of which use the techniques and ontologies in solving a known problem.
89

Automation of railway switch and crossing inspection

Rusu, Marius Florin January 2017 (has links)
In recent years there has been an increase in railway usage which led to reduced time for rail maintenance. Railway switches and crossings (S&C) are an important asset and they typically account for 30% of the total budget spent on maintenance. The first part of this work researches the feasibility of automatically inspecting S&Cs in accordance with Network Rail inspection requirements and the likely necessary advancements. Current S&C inspection requirements, as well as current and developing inspection solutions, were analysed and categorised. This revealed the required technological advances and likely changes that the railway will have to adopt. The second part of the work researches the weakness of conventional S&C profile inspection practices used in industry. The work identified the main reasons that can lead to poor traditional inspection of the S&C profile, developed a novel, automatic method to carry out the profile measurements which eliminated human error and identified possible improvements in the area of S&C profile inspection. During this research, an inspection trolley was prototyped, field trials were carried out, and good results were obtained.
90

Metro traffic optimisation accounting for the disbenefit of halting between stations

Ueda, Naoki January 2005 (has links)
Computerised regulation for disturbed traffic in metro-type railways is proposed. Previous work has used optimisation techniques to minimise disbenefits to passengers, such as waiting time and journey time, in the objective function. The particular disbenefit of trains being halted between stations is introduced in this thesis, in combination with those already mentioned. An effective method in real operations for preventing trains being halted between stations is to hold trains already at stations and to allow running trains to reach the next station when a particular train departure is delayed. The proposed algorithm uses this ‘stop-all-trains-at-once’ philosophy combined with optimisation ideas, in a sequentially structured approach. A further consideration from real operations is the fact that it is not possible to predict precisely when the delayed train will re-start. Estimates of the re-starting time will improve as the delay increases, and the proposed scheme takes this into account. Numerous simulations were undertaken to investigate the performance of the regulation algorithm. It is shown that the proposed regulation algorithm is effective in reducing the disbenefit to passengers from disturbed traffic for various characteristic metros with different passenger flows.

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