• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 29
  • 7
  • 6
  • 4
  • 1
  • Tagged with
  • 63
  • 63
  • 10
  • 9
  • 8
  • 8
  • 8
  • 8
  • 7
  • 7
  • 7
  • 7
  • 6
  • 6
  • 6
  • 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.
41

Ethylglucuronid in Haaren

Ammann, Dominic 21 November 2017 (has links)
Obwohl EtG seit dem Jahr 2000 intensiv als Alkoholmarker in Haaren beforscht wird, bietet die Thematik weiterhin Raum für Forschung, insbesondere im Bereich der instrumentellen Analytik. Ziel der vorliegenden Arbeit ist die Beleuchtung dieser und weiterer Aspekte. Die Extraktion erfolgte überwiegend mittels der sogenannten Mikropulverisierung. Sie ermöglichte die simultane Mahlung der Haarmatrix und Extraktion des EtGs mit einem hohen Probendurchsatz. Die Selektion und anschließende Detektion erfolgte überwiegend durch HPLC-MS/MS. Die Sicherheit bei der Bestimmung des Analyten wurde durch die erfolgreiche Teilnahme an drei Ringversuchen der Society of Hair Testing (SoHT) belegt. Wiederholbedingungen wurden durch Herstellung von eigenen Haarreferenzmaterialien und die Verwendung von homogenen Fremdhaarmaterialien sichergestellt. Zur Evaluierung der Stabilität von EtG wurden zwei Haarmaterialien unter thermischen Stressbedingungen eingelagert und mit dem Gehalt von Referenzproben verglichen. Der Analyt zeigte außergewöhnliche Stabilität unter den gewählten Bedingungen. Ebenso erfolgte eine Beurteilung des Zerstörungsgrads von EtG im Haar durch oxidierende Substanzen, einhergehend mit der Entwicklung eines zerstörungsfreien Schnelltests mittels FTIR zur Detektion von oxidierten Cysteinspezies in Haaren. Das Modellsystem Barthaar wurde für zwei Experimentreihen etabliert: die Korrelation des EtG-Gehaltes im Barthaar nach Aufnahme definierter Alkoholmengen und den Nachweis von glucuronidierten Spezies im Barthaar nach Aufnahme der korrespondierenden Muttersubstanzen. Während keine eindeutige Korrelation zwischen aufgenommener Alkoholmenge und EtG-Gehalt im Barthaar hergestellt werden konnte, war es durchaus möglich, zwei glucuronidierte Metabolite von Arzneistoffen im Barthaar nach Konsum der Ausgangssubstanzen nachzuweisen. / Although EtG is subject to extended research since the year 2000, the topic still holds headroom for further experiments, especially when it comes to the field of instrumental analysis. The goal of the present thesis was the clarification of crucial analytical and further aspects. The extraction was mostly carried out using the so-called micropulverisation. It rendered the simultaneous milling of the hair matrix and extraction of EtG possible with a high sample throughput. Selection of the analyte and following detection was mainly carried out using HPLC-MS/MS. The quality of analysis was ensured by the successful participation in three interlaboratory tests carried out by the Society of Hair Testing (SoHT). Repetitive conditions were ensured by manufacturing of own hair reference materials as well as by the usage of homogeneous external hair materials. Two hair materials were treated under thermal stress conditions and the EtG values were compared to reference samples to verify the analytes stability. EtG showed extraordinary stability under the chosen conditions. Likewise, an assessment of the degree of EtG decay after oxidative treatment as well as the development of a nondestructive assay via FTIR to detect oxidized cysteine species were established. The model system beard hair was arranged for the conduction of two experimental series: the correlation of the EtG content in beard hair after defined oral consumption of ethanol and the detection of glucuronidation of the corresponding parent substances after consumption. Whilst no distinct correlation could be observed for the ethanol experiment, it was possible to provide evidence for the existence of two glucuronized metabolites of drugs after consumption of the parent compounds.
42

A trust framework for multi-organization environments

Toumi, Khalifa 01 April 2014 (has links) (PDF)
The widespread of inexpensive communication technologies, distributed data storage and web services mechanisms currently urge the collaboration among organizations. Partners are participating in this environment motivated by several advantages such as: (1) the ability to use external and professional resources, services and knowledge, (2) the reduction of time-consuming requirements and (3) the benefaction of experts experience. However, this collaboration is not perfect since several problems can arise such as the misuse of resources, disclosure of data or inadequate services. Therefore, security is an important concern of the participants. In particular trust management and access control are one of the major security issues for an organization. This thesis addresses these two areas in particular. It proposes a novel and comprehensive trust framework for Multi-Organization Environments. Our approach is organized in four parts. First, we propose a vector based model approach for defining trust vectors. These vectors evaluate a set of requirements, under conditions, and provide a degree of confidence. In our approach, we consider two different types of vectors. On the one hand, a vector that links a user to an organization and, on the other hand, a vector that links two organizations. We also show how these vectors are evaluated and shared among the different organizations, and how we combine the provided trust information in order to enhance the security. Second, the TRUST-OrBAC model was designed to add the previous trust approach to the ORBAC model. Moreover, this solution was applied with a real collaboration network between companies. Third, we present a trust ontology methodology based on access control concepts. This ontology will be used to share the trust beliefs between participants and to make equivalence between their trust objectives. How to define this trust relationship, how to understand the trust objective of a requester, and how to evaluate the recommendation value is addressed in this thesis. Fourth, we improve our work by designing a passive testing approach in order to evaluate the behavior of a user. This contribution is based on the monitoring tool MMT. Finally the entire architecture of our system is proposed
43

Development of novel analytical and interpretational protocols to facilitate the provenance establishment of glass and plastic evidence

May, Christopher David January 2009 (has links)
[Truncated abstract] The analysis and subsequent interpretation of trace evidence is of paramount importance to the forensic scientist. While a variety of methods are available to facilitate comparison between recovered and control samples, the use of a specific analytical method depends upon both the physical and chemical nature of the material itself and the material to which it is to be compared. Elemental analysis of evidentiary material is one such method of sample comparison and has been extensively applied to this purpose following the introduction of neutron activation analysis in the early 1960s. However, over the last 15 years, another instrumental technique has taken centre stage in the analytical armoury of the forensic scientist: laser ablation–inductively coupled plasma-mass spectrometry (LA-ICP-MS). The modification and adaptation of this technique, to a point where it is possible to distinguish between glass materials produced only hours apart on the same production line, is detailed in this thesis. Additional protocols have also been developed for the analysis of fibreglass and plastic crime scene debris. Finally, a method for quantification of elemental concentrations in headlamp plastics has also been developed to facilitate inter-comparison of data between both different analytical techniques and different laboratories. Glass material is one of the most common varieties of trace evidence and the forensic examination of glass traditionally involves the determination of its refractive index (RI). ... The analytical protocol involves the analysis of 46 analytes on material comprising the exterior surface of the lens. Using this data, it was found that although minor variations in elemental composition exist within a single headlamp lens, discrimination between lenses produced from a single manufacturing plant over a short period of time could still be achieved. Discrimination between all headlamp lenses, with the exception of some lenses produced on the same day, could be facilitated using the analytical protocol developed. Furthermore, an interpretational protocol has been developed that has successfully classified all unknown headlamp lens samples investigated in this study, within the discrimination limits of the analytical method. The semi-quantitative analysis of glass and plastic samples has also been examined using LA-ICP-MS. The concentrations of 16 analytes in container and float glass samples were determined. However, the levels of discrimination afforded by the semi-quantitative data were inferior to those achieved using qualitative data. Finally, a series of plastic-based standards, containing 25 analytes of known concentrations, was produced. Using these standards, relative concentrations of the study analytes were determined in polycarbonate headlamp lenses. Interpretation of the data produced made it possible to discriminate between all study samples. Consequently, the total analytical and interpretational protocol developed in this study has established the foundation for LA-ICP-MS to be adopted internationally as a recognised method for the analysis of plastic crime scene debris.
44

Aide à l'analyse de traces d'exécution dans le contexte des microcontrôleurs 32 bits / Assit to execution trace analysis in the microcontrollers 32 bits context

Amiar, Azzeddine 27 November 2013 (has links)
Souvent, dû à l'aspect cyclique des programmes embarqués, les traces de microcontrôleurs contiennent beaucoup de données. De plus, dans notre contexte de travail, pour l'analyse du comportement, une seule trace se terminant sur une défaillance est disponible. L'objectif du travail présenté dans cette thèse est d'aider à l'analyse de trace de microcontrôleurs. La première contribution de cette thèse concerne l'identification de cycles, ainsi que la génération d'une description pertinente de la trace. La détection de cycles repose sur l'identification du loop-header. La description proposée à l'ingénieur est produite en utilisant la compression basée sur la génération d'une grammaire. Cette dernière permet la détection de répétitions dans la trace. La seconde contribution concerne la localisation de faute(s). Elle est basée sur l'analogie entre les exécutions du programme et les cycles. Ainsi, pour aider dans l'analyse de la trace, nous avons adapté des techniques de localisation de faute(s) basée sur l'utilisation de spectres. Nous avons aussi défini un processus de filtrage permettant de réduire le nombre de cycles à utiliser pour la localisation de faute(s). Notre troisième contribution concerne l'aide à l'analyse des cas où les multiples cycles d'une même exécution interagissent entre eux. Ainsi, pour faire de la localisation de faute(s) pour ce type de cas, nous nous intéressons à la recherche de règles d'association. Le groupement des cycles en deux ensembles (cycles suspects et cycles corrects) pour la recherche de règles d'association, permet de définir les comportements jugés correctes et ceux jugés comme suspects. Ainsi, pour la localisation de faute(s), nous proposons à l'ingénieur un diagnostic basé sur l'analyse des règles d'association selon leurs degrés de suspicion. Cette thèse présente également les évaluations menées, permettant de mesurer l'efficacité de chacune des contributions discutées, et notre outil CoMET. Les résultats de ces évaluations montrent l'efficacité de notre travail d'aide à l'analyse de traces de microcontrôleurs. / The microcontroller traces contain a huge amount of information. This is mainly due to the cyclic aspect of embedded programs. In addition, in our context, a single trace that ends at the failure is used to analyze the behavior of the microcontroller . The work presented in this thesis aims to assit in analysis of microcontroller traces. The first contribution of this thesis concerns the identification of cycles and the generation of a relevant description of the trace. The detection of cycles is based on the identification of the loop-header. The description of the trace is generated using Grammar-Based Compression, which allows the detection of repetitions in the trace. The second contribution concerns the fault localization. Our approach is based on the analogy between executions and cycles. Thus, this contribution is an adaptation of some spectrum-based fault localization techniques. This second contribution also defines a filtering process, which aims to reduce the number of cycles used by the fault localization. The third contribution considers that the multiple cycles of a same execution can interact together. Our fault localization for this type of cases is based on the use of association rules. Grouping cycles in two sets (suspect cycles and correct cycles), and searching for association rules using those two sets, helps to define the behaviors considered as corrects and those considered as suspects. This thesis presents the experimental evaluations concerning our contributions, and our tool CoMET.
45

Determinação simultânea de Cd, Pb e Cu em amostras de chá (Camellia sinensis) por voltametria de onda quadrada e redissolução anódica

Medeiros, Cleilson Lucena de 31 August 2015 (has links)
Submitted by Maike Costa (maiksebas@gmail.com) on 2016-05-04T13:53:54Z No. of bitstreams: 1 arquivo total.pdf: 4473867 bytes, checksum: e3130e71f9f870684d06304ce755007d (MD5) / Made available in DSpace on 2016-05-04T13:53:54Z (GMT). No. of bitstreams: 1 arquivo total.pdf: 4473867 bytes, checksum: e3130e71f9f870684d06304ce755007d (MD5) Previous issue date: 2015-08-31 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This paper describes the development of a method for quantification Cd2+, Pb2+ and Cu2+ cations, in teas, performed simultaneously, using Square Wave Anodic Stripping Voltammetry carbon nanotube paste electrode modified with bismuth film. Tea is one of the most beneficial and consumed beverage through the world, being prepared from the infusion parts of the plant Camellia sinensis. Most commonly this kind of tea presents metal ions, such as Cd 2+, Pb 2+ and Cu 2+, which offers health risk, in case of being ingested above the limit. To detect these metals, it is necessary to make use of techniques with high sensitivity. The spectrometric methods are the most widely used, but they have a high cost, are laborious and expensive. The voltammetric techniques are characterized by being inexpensive and having equal sensitivity, and even greater than some spectrometric methods. The parameters of the technique used were obtained after optimization with fractional factorial design. The tea samples were prepared through digestion with heating by microwave radiation in a closed system using diluted nitric acid and hydrogen peroxide. The method was validated based on the sample certified plant tissue (forage Marandu) and applied in green and black tea samples. Recoveries of cations Cd 2+, Pb 2+ and Cu 2+ ranged from 79.3 to 107.6%, the certified sample, and 73.3 to 122.1% in the evaluated samples of teas. The detection limits obtained in the simultaneous analysis of Cd 2+, Pb 2+ and Cu 2+ were 0.16; 0.20; 0.39 ug L-1, respectively. Cu2 + was detected only in samples of tea, but the method was efficient for the simultaneous quantification of all metals in the matrix assessed after the addition and recovery. / Este trabalho descreve o desenvolvimento de um método de quantificação dos cátions Cd2+, Pb2+ e Cu2+, em chás, realizada de forma simultânea, empregando voltametria de onda quadrada por redissolução anódica com eletrodo de pasta de nanotubo de carbono modificado por filme de bismuto. O chá é uma das bebidas mais benéficas e consumidas no mundo, sendo preparado a partir da infusão de partes da planta Camellia sinensis. Normalmente são encontrados cátions metálicos, como o Cd2+, Pb2+ e Cu2+, que se ingeridos acima do limite máximo representam riscos à saúde. Para detectar esses metais é necessário fazer uso de técnicas com alta sensibilidade. Os métodos espectrométricos são os que mais amplamente tem sido utilizado, porém apresentam custo elevado, são laboriosos e dispendiosos. As técnicas voltamétrica caracterizam-se por serem baratas e possuir sensibilidade igual e até maior que alguns métodos espectrométricos. Os parâmetros da técnica utilizada foram obtidos após otimização com planejamento fatorial fracionário. As amostras de chá foram preparadas via digestão com aquecimento por radiação micro-ondas em sistema fechado empregando ácido nítrico e peróxido de hidrogênio diluídos. A validação do método foi realizada com base na amostra certificada de tecido vegetal (forrageira Marandu) e aplicada em amostras de chá verde e preto. As recuperações dos cátions Cd2+, Pb2+ e Cu2+ variaram de 79,3 a 107,6%, na amostra certificada, e de 73,3 a 122,1% nas amostras de chás avaliadas. Os limites de detecção obtidos na análise simultânea de Cd2+, Pb2+ e Cu2+, foram 0,16; 0,20; 0,39 μg L-1, respectivamente. Foi detectado apenas Cu2+ nas amostras de chá, porém o método se mostrou eficiente para quantificação simultânea de todos os metais na matriz avaliada após a adição e recuperação.
46

MODEL-BASED SIMULATION OF AUTOMOTIVE SOFTWARE SYSTEMS

Kozhakenov, Temirzhan January 2020 (has links)
The car is the most common vehicle in the world. Millions of cars are produced annually. In order for each car to find its buyer, car companies are forced to constantly improve the design of the car. Modern models are emerging, new car systems are being developed and implemented. All this is accompanied by a huge flow of information, in which it is easy to get lost. This master’s work is devoted to the trace analysis and connection of two different files. The paper proposes a developed algorithm of trace analysis for some functions of the vehicle in the C++ programming language. The files that we use to trace analysis relate to the model and the final result of its simulation.EATOP is a tool with which a model based on the EAST-ADL language was developed. Adapt is an event simulator with which our model of automotive functionality was simulated. The purpose of the study is to identify possible ways to meet timing requirements. The work is carried out in collaboration with Volvo Group Truck Technology. This company provided the LogFile, which presents results of the simulation, and model. We get an analysis of performance, one of the ways to trace data and timing. The results of our implementation are presented and discussed.
47

Traces d'utilisations et mutilations sur les armes laténiennes : l'exemple des armes du site de La Tène conservées au Laténium / Use-Wear weapons on La Tène weapons : the example of Laténium

Reich, Guillaume 29 June 2018 (has links)
La principale collection d’armes du site de La Tène (armes de poing, d’hast, de jet, boucliers) est étudiée sous l’angle de la tracéologie. Les armes du Laténium sont dans l’ensemble bien préservées du fait de l’anaérobie, parfois recouvertes d’une simple patine. L’approche de cette thèse de doctorat est basée sur un croisement disciplinaire entre l’analyse typo-chronologique, l’archéologie expérimentale, « l’ethno-archéologie » et les sciences forensiques. Est-ce possible, à compter de traces visibles sur les objets de La Tène, mais également sur d’autres sites laténiens, d’interpréter les traces de destructions sur les armes ? Ces dernières sont-elles plutôt imputables à des actes rituels volontaires ou faut-il y voir les résultats accidentels de combats ? Il ne s’agit pas ici de trancher définitivement l’épineuse question de la fonction du site de La Tène, mais d’apporter quelques pistes de réflexion sur l’interprétation de ce « gisement » énigmatique (sanctuaire, trophée militaire,…). / The weapons from the main collection from La Tène (impact and thrusting weapons, lances, projectiles/throwing spears, shields) have been analysed for use-wear. Due to the anaerobic conditions, the pieces at the Laténium are largely well preserved, with many bearing a simple patina. This PhD thesis combines chronotypology, experimental archaeology, «ethnoarchaeology» and forensics to answer the following question : is it possible by examining the traces visible on the objects from La Tène and other sites to as certain whether the weapons were put beyond use deliberately, as part of a ritual, or did it occur during combat ? The objective is not to deduce the function of the enigmatic site (sanctuary, monument to a military victory,…) but to find ways of interpreting it.
48

Interpretation von Dimensionsinkonsistenzen in Fragebögen der AIID-Studie

Zahn, Elisa 21 August 2023 (has links)
Eindimensionalität ist ein wichtiges Merkmal psychometrischer Tests und wird in der Psychologie momentan vor allem unter Anwendung der Faktorenanalyse geprüft. Da diese aber nicht das zu leisten scheint, was von ihr erwartet wird (z. B. Titz, 2022; Ziegler & Hagemann, 2015), wurde in der vorliegenden Arbeit eine Vorgehensweise mit der State-Trace-Analyse (Bamber, 1979) angewendet, um der Frage nach Eindimensionalität nachzugehen. Dazu wurden vier Persönlichkeitsfragebögen, die auf faktorenanalytischen Verfahren basieren und aus einem Datensatz der AIID-Studie stammen (Hussey & Hughes, 2020; Hussey et al., 2012), im Vorfeld der Arbeit State-Trace-Analysen unterzogen. Items, die die Bedingung der Eindimensionalität verletzten, wurden in der vorliegenden Arbeit mit Hilfe von Diagrammen näher untersucht und interpretiert. Es hat sich gezeigt, dass die State-Trace-Analyse Items identifizieren konnte, die die Eindimensionalität der Fragebögen infrage stellen und laut Faktorenanalyse unentdeckt blieben. Inhaltliche Interpretationen konnten unterstützen, dass die Items wahrscheinlich problematisch für die Eindimensionalität der untersuchten Verfahren sind und überarbeitet werden müssen. Die State-Trace-Analyse bietet hohes Potenzial für psychometrische Fragestellungen und muss in Zukunft mehr Aufmerksamkeit erhalten.
49

A Heuristic-Based Approach to Real-Time TCP State and Retransmission Analysis

Swaro, James E. January 2015 (has links)
No description available.
50

Capitalisation et partage de connaissances d’analyse de traces numériques d’activités : assister le suivi de l'activité dans les environnements de formation à base de simulateur pleine échelle / Capitalizing and sharing analysis knowledge of digital traces of activities : assist the monitoring of activity in full scale simulator-based training environments

Champalle, Olivier 04 July 2014 (has links)
Nos recherches s'inscrivent dans le domaine de l'ingénierie des connaissances et plus particulièrement dans la capitalisation et le partage de connaissances d'observation et d'analyse de traces numériques d'activités. Dans ce cadre, nous basons notre approche sur le concept de la trace modélisée (M-Trace) développée par l'équipe SILEX. Au travers de notre approche nous donnons la possibilité d'exploiter des traces numériques d'activités de bas niveaux pour faire émerger des connaissances de plus haut niveaux obtenues via des transformations à base de règles. Ces règles modélisent des connaissances d'observation et d'analyse de différents utilisateurs et sont capitalisables et partageables entre ces derniers. Nous complétons notre proposition en fournissant une visualisation synthétique des niveaux de connaissances et de leurs observés. Via un modèle générique de trace, que nous avons développé, cette synthèse visuelle est navigable afin de permettre aux utilisateurs d'explorer les différents niveaux de connaissances et de reconstituer le chemin de construction des observables entre les niveaux, facilitant ainsi l'analyse. Nos différentes propositions ont été réifiées dans un logiciel du nom de D3KODE (« Define, Discover, and Disseminate Knowledge from Observation to Develop Expertise »). Ce logiciel a été mis à l'épreuve dans le contexte de la formation professionnelle sur les simulateurs pleine échelle du groupe EDF utilisés pour la formation et le perfectionnement des agents de conduite de centrale nucléaire. Dans un tel cadre l'observation, l'analyse et le débriefing des interactions individuelles et collectives des opérateurs sont des activités critiques et particulièrement dense notamment pour les jeunes formateurs. Les données collectées sont difficilement exploitables dû à leur grande quantité et à leur très bas niveau nécessitant une expertise forte que tous les formateurs ne possèdent pas. Ce travail a donné lieu à une évaluation en contexte réel sur simulateur pleine échelle et à des résultats significatifs permettant de valider notre approche et d'encourager des perspectives de recherche nombreuses / Our research takes place in the field of knowledge engineering. In particularly we focus our study in capitalizing and sharing knowledge of observation and analysis of digital traces. In this context, we base our approach on the concept of modeled trace (M-Trace) developed by the SILEX team. Our approach give the possibility to exploit low levels digital traces in order to extract higher knowledge level through rule-based transformations. These rules modelize the knowldege of observation and analysis of different users. Rules can be capitalized and shared between users. We complete our proposal by providing a synthetic visualization of the knowledge levels with observed elements from the activity. By means of a generic trace model, that we have specified, users can explore the different abstraction level in purposes of investigation in order to better understand and analyze the activity. Our proposals have been implemented in a prototype, called D3KODE (« Define, Discover, and Disseminate Knowledge from Observation to Develop Expertise »), allowing the processing, representation and visualization of traces. D3KODE was applied in the context of professional training on the nuclear power plant full-scope simulator of the EDF group designed to maintain and enhance the knowledge and skills of Nuclear Power Plant control room staff. In such context, the observation, analysis and debriefing of individual and collective interactions of trainees’ operators is a dense activity that require attention and constant alertness of the trainers throughout the simulation, especially for the young trainers who do not have the expertise of confirmed trainers. The amount of data collected during a simulation is big and very low levels. They are difficult to analyse manually in order to extract high level information reflecting the behaviour of trainees. In such a context, understand and follow the activity requires a strong expertise that all trainers don’t have. So as to validate our approach, D3KODE was evaluated in a real context according to a comparative protocol conducted with a team of trainers from EDF Group. The evaluation gave significant results to validate our approach and encourage many research opportunities

Page generated in 0.4424 seconds