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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.
211

Imagerie moléculaire d’empreintes digitales par spectrométrie de masse : potentiels et applications en science forensique

Lauzon, Nidia 04 1900 (has links)
No description available.
212

Towards an ICT artefact for financial inclusion in Ghana: a critical realist perspective

Agyepong, Stephen 02 1900 (has links)
Financial exclusion is a major developmental problem. Perception has it that financial exclusion emanates from the lack of access to banking and financial services, and the general understanding is that ICT-based access to such services is the solution. In this research, which was undertaken in Ghana, Critical Realism (CR) revealed deeper causes (generative mechanisms) that underlie financial exclusion. The research followed a mixed-method approach. The CR approach guided the research to create an initial model from which hypotheses were deduced and tested; the design science approach, guided the research to create the design theory and an instantiation of an application that uses the design theory; and the quantitative method, was used to evaluate the hypotheses. CR revealed how, in a credit economy, people have a need for credit to pursue business or education opportunities. The generative mechanisms identified have revealed how the credit market for the unbanked includes the reality that a wellfunctioning credit market is self-sustaining with two mechanisms: signalling and adoption. The signalling mechanism facilitates users’ access to credit, which they in turn are able to spend on more services. On the other hand, the adoption mechanism enables the development of more services making the market more valuable, thus attracting more users in a self-feeding loop. The key findings suggest that being banked does not necessarily lead to financial inclusion and financial wellbeing. Transactional banking only serves as an "enrichment agenda for the banks", with minimal benefit to the people. There are also other non-financial technologies such as sharing and social technologies that have an effect on the provision of credit; in addition to their main purpose of saving and/or earning income, for the unbanked, by sharing resources. In Ghana, despite having bank accounts, most of the banked do not use them, because of cost and inappropriate services. This research reveals that the unexamined notion of being banked as a fundamental requirement for financial inclusion may require further investigation. The research has found that the unbanked keeping to themselves and the use of cash creates anonymity and makes them invisible to formal financial institutions, who prefer identity over anonymity, thus contributing to their financial exclusion. The following design needs were identified: inexpensive credit and value-added services such as saving groups, financial accounting services, service to report delinquent customers and education. The research offers a conceptualization of a financial inclusion ICT artefact to draw attention to the multifaceted and complex environment financial inclusion effort is immersed. This calls for an integrated approach since the issues with financial exclusion extend beyond financials and have an effect on the broader society. The research, therefore, proposes a substantive framework for improving the design and development of financial inclusive systems, which helps build trust using obligation transactions. It offers an approach to computing an individual’s financial inclusiveness, which also helps safeguard his/her financial wellbeing. The thesis makes a contribution to Information Systems theory in proposing a framework on financial inclusion using ICT. The contribution to practice is the design of an ICT artefact. / School of Computing / Ph. D. (Computer Science)
213

Le niveau de la mer actuel : variations globales et régionales / Present day sea level : global and regional variations

Kulaiappan Palanisamy, Hindumathi 06 January 2016 (has links)
Le niveau de la mer est une des variables climatiques essentielles dont la variabilité résulte de nombreuses interactions complexes entre toutes les composantes du système climatique sur une large gamme d'échelles spatiales et temporelles. Au cours du XXème siècle, les mesures marégraphiques ont permis d'estimer la hausse du niveau de la mer global entre 1,6 mm/an et 1,8 mm/an. Depuis 1993, les observations faites par les satellites altimétriques indiquent une hausse du niveau de la mer plus rapide de 3,3 mm/an. Grâce à leur couverture quasi-globale, elles révèlent aussi une forte variabilité du niveau de la mer à l'échelle régionale, parfois plusieurs fois supérieure à la moyenne globale du niveau de la mer. Compte tenu de l'impact très négatif de l'augmentation du niveau de la mer pour la société, sa surveillance, la compréhension de ses causes ainsi que sa prévision sont désormais considérées comme des priorités scientifiques et sociétales majeures. Dans cette thèse, nous validons d'abord les variations du niveau de la mer mesurées par la nouvelle mission d'altimétrie satellitaire, SARAL-AltiKa, en comparant les mesures avec celles de Jason- 2 et des marégraphes. Un autre volet de cette première partie de thèse a consisté à estimer les parts respectives des facteurs responsables des variations du niveau de la mer depuis 2003 en utilisant des observations issues de l'altimétrie satellitaire (missions altimétrique Jason-1, Jason-2 et Envisat), de la mission GRACE, et des profils de température et salinité de l'océan par les flotteurs Argo. Une attention particulière est portée à la contribution de l'océan profond non 'vue' par Argo. Nous montrons que les incertitudes dues aux approches du traitement des données et aux erreurs systématiques des différents systèmes d'observation nous empêchent encore d'obtenir des résultats précis sur cette contribution. Dans la deuxième partie de la thèse, en utilisant les données de reconstruction du niveau de la mer dans le passé, nous étudions la variabilité régionale du niveau de la mer et estimons sa hausse totale (composante régionale plus moyenne globale) de 1950 à 2009 dans trois régions vulnérables: l'océan Indien, la mer de Chine méridionale et la mer des Caraïbes. Pour les sites où l'on dispose de mesures du mouvement de la croûte terrestre par GPS, nous évaluons la hausse locale du niveau de la mer relatif (hausse du niveau de la mer totale plus mouvement de la croûte locale) depuis 1950. En comparant les résultats de ces trois régions avec une étude précédente sur le Pacifique tropical, nous constatons que le Pacifique tropical présente la plus forte amplitude des variations du niveau de la mer sur la période d'étude. Dans la dernière partie de la thèse, nous nous concentrons par conséquent sur le Pacifique tropical. Nous analysons les rôles respectifs de la dynamique océanique, des modes de variabilité interne du climat et du forçage anthropique sur les structures de la variabilité régionale du niveau de la mer du Pacifique tropical depuis 1993. Nous montrons qu'une partie importante de la variabilité régionale du niveau de la mer du Pacifique tropical peut être expliquée par le mouvement vertical de la thermocline en réponse à l'action du vent. En tentant de séparer le signal correspondant au mode de variabilité interne du climat de celui de la hausse régionale du niveau de la mer dans le Pacifique tropical, nous montrons également que le signal résiduel restant (c'est-à-dire le signal total moins le signal de variabilité interne) ne correspond probablement pas à l'empreinte externe du forçage anthropique. / Sea level is an integrated climate parameter that involves interactions of all components of the climate system (oceans, ice sheets, glaciers, atmosphere, and land water reservoirs) on a wide range of spatial and temporal scales. Over the 20th century, tide gauge records indicate a rise in global sea level between 1.6mm/yr and 1.8 mm/yr. Since 1993, sea level variations have been measured precisely by satellite altimetry. They indicate a faster sea level rise of 3.3 mm/yr over 1993-2015. Owing to their global coverage, they also reveal a strong regional sea level variability that sometimes is several times greater than the global mean sea level rise. Considering the highly negative impact of sea level rise for society, monitoring sea level change and understanding its causes are henceforth high priorities. In this thesis, we first validate the sea level variations measured by the new satellite altimetry mission, SARAL-AltiKa by comparing the measurements with Jason-2 and tide gauge records. We then attempt to close the global mean sea level budget since 2003 and estimate the deep ocean contribution by making use of observational data from satellite altimetry, Argo profiles and GRACE mission. We show that uncertainties due to data processing approaches and systematic errors of different observing systems still prevent us from obtaining accurate results. In the second part of the thesis, by making use of past sea level reconstruction, we study the patterns of the regional sea level variability and estimate climate related (global mean plus regional component) sea level change over 1950-2009 at three vulnerable regions: Indian Ocean, South China and Caribbean Sea. For the sites where vertical crustal motion monitoring is available, we compute the total relative sea level (i.e. total sea level rise plus the local vertical crustal motion) since 1950. On comparing the results from these three regions with already existing results in tropical Pacific, we find that tropical Pacific displays the highest magnitude of sea level variations. In the last part of the thesis, we therefore focus on the tropical Pacific and analyze the respective roles of ocean dynamic processes, internal climate modes and external anthropogenic forcing on tropical Pacific sea level spatial trend patterns since 1993. Building up on the relationship between thermocline and sea level in the tropical region, we show that most of the observed sea level spatial trend pattern in the tropical Pacific can be explained by the wind driven vertical thermocline movement. By performing detection and attribution study on sea level spatial trend patterns in the tropical Pacific and attempting to eliminate signal corresponding to the main internal climate mode, we further show that the remaining residual sea level trend pattern does not correspond to externally forced anthropogenic sea level signal. In addition, we also suggest that satellite altimetry measurement may not still be accurate enough to detect the anthropogenic signal in the 20 year tropical Pacific sea level trends.
214

The admissibility and evaluation of scientific evidence in court

Faurie, Annari 11 1900 (has links)
Increasing use is being made of various types of scientific evidence in court. The general requirement for the admissibility of such evidence is relevance. Although expert evidence is considered to be opinion evidence, it is admissible if it can assist the court to decide a fact in issue; provided that it is also reliable. In South Africa, the initial wide judicial discretion to either admit or exclude unconstitutionally obtained evidence, has developed into a more narrowly defined discretion under the final Constitution. Examples of scientific evidence, namely, DNA evidence, fingerprints, psychiatric evidence, bite-mark evidence and polygraph evidence are considered and problems inherent in the presentation of such evidence in courts in various jurisdictions are highlighted. An investigation of the presentation and evaluation of evidence in both the accusatorial and inquisitorial systems seems to indicate that the adversarial procedure has a marked influence on the evaluation of evidence / Criminal and Procedural Law / LL.M. (Law)
215

Tracing and apportioning sources of dioxins using multivariate pattern recognition techniques

Assefa, Anteneh January 2015 (has links)
High levels of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) in edible fish in the Baltic Sea have raised health concerns in the Baltic region and the rest of Europe. Thus, there are urgent needs to characterize sources in order to formulate effective mitigation strategies. The aim of this thesis is to contribute to a better understanding of past and present sources of PCDD/Fs in the Baltic Sea environment by exploring chemical fingerprints in sediments, air, and biota. The spatial and temporal patterns of PCDD/F distributions in the Baltic Sea during the 20th century were studied in Swedish coastal and offshore sediment cores. The results showed that PCDD/F levels peaked in 1975 (± 7 years) in coastal and 1991 (± 5 years) in offshore areas. The time trends of PCDD/Fs in the sediment cores also showed that environmental half-lives of these pollutants have been shorter in coastal than in offshore areas (15 ± 5 and 29 ± 14 years, respectively). Consequently, there have been remarkable recoveries in coastal areas, but slower recovery in offshore areas with 81 ± 12% and 38 ± 11% reductions from peak levels, respectively. Source-to-receptor multivariate modeling by Positive Matrix Factorization (PMF) showed that six types of PCDD/F sources are and have been important for the Baltic Sea environment: PCDD/Fs related to i) atmospheric background, ii) thermal processes, iii) manufacture and use of tetra-chlorophenol (TCP) and iv) penta-chlorophenol (PCP), v) industrial use of elementary chlo- rine and the chloralkali-process (Chl), and vi) hexa-CDD sources. The results showed that diffuse sources (i and ii) have consistently contributed >80% of the total amounts in the Southern Baltic Sea. In the Northern Baltic Sea, where the biota is most heavily contaminated, impacts of local sources (TCP, PCP and Chl) have been higher, contributing ca. 50% of total amounts. Among the six sources, only Thermal and chlorophenols (ii-iv) have had major impacts on biota. The impact of thermal sources has, however, been declining as shown from source apportioned time-trend data of PCDD/Fs in Baltic herring. In contrast, impacts of chlorophenol-associated sources generally increased, remained at steady-state or slowly decreased during 1990-2010, suggesting that these sources have substantially contributed to the persistently high levels of PCDD/Fs in Baltic biota. Atmospheric sources of PCDD/Fs for the Baltic region (Northern Europe) were also investigated, and specifically whether the inclusion of parallel measurements of metals in the analysis of air would help back-tracking sources. PCDD/Fs and metals in high-volume air samples from a rural field station near the shore of the central Baltic Sea were measured. The study focused on the winter season and air from the S and E sectors, as these samples showed elevated levels of PCDD/Fs, particularly PCDFs. Several metals were found to correlate significantly with the PCDFs. The wide range of candidate metals as source markers for PCDD/F emissions, and the lack of an up-to-date extensive compilation of source characteristics for metal emission from vari- ous sources, limited the use of the metals as source markers. The study was not able to pin-point primary PCDD/F sources for Baltic air, but it demonstrated a new promising approach for source tracing of air emissions. The best leads for back-tracking primary sources of atmospheric PCDD/Fs in Baltic air were seasonal trends and PCDD/F congener patterns, pointing at non-industrial related thermal sources related to heating. The non-localized natures of the sources raise challenges for managing the emissions and thus societal efforts are required to better control atmospheric emissions of PCDD/Fs. / EcoChange / BalticPOPs
216

Bezpečnost biometrických systémů / Security of Biometric Systems

Lodrová, Dana Unknown Date (has links)
Hlavním přínosem této práce jsou dva nové přístupy pro zvýšení bezpečnosti biometrických systémů založených na rozpoznávání podle otisků prstů. První přístup je z oblasti testování živosti a znemožňuje použití různých typů falešných otisků prstů a jiných metod oklamání senzoru v průběhu procesu snímání otisků. Tento patentovaný přístup je založen na změně barvy a šířky papilárních linií vlivem přitlačení prstu na skleněný podklad. Výsledná jednotka pro testování živosti může být integrována do optických senzorů.  Druhý přístup je z oblasti standardizace a zvyšuje bezpečnost a interoperabilitu procesů extrakce markantů a porovnání. Pro tyto účely jsem vytvořila metodologii, která stanovuje míry sémantické shody pro extraktory markantů otisků prstů. Markanty nalezené testovanými extraktory jsou porovnávány oproti Ground-Truth markantům získaným pomocí shlukování dat poskytnutých daktyloskopickými experty. Tato navrhovaná metodologie je zahrnuta v navrhovaném dodatku k normě ISO/IEC 29109-2 (Amd. 2 WD4).
217

A hidden life : how EAS (Era Appropriate Science) and professional investigators are marginalised in detective and historical detective fiction

Dormer, Mia Emilie January 2017 (has links)
This by-practice project is the first to provide an extensive investigation of the marginalisation of era appropriate science (EAS) and professional investigators by detective and historical detective fiction authors. The purpose of the thesis is to analyse specific detective fiction authors from the earliest formats of the nineteenth century through to the 1990s and contemporary, selected historical detective fiction authors. Its aim is to examine the creation, development and perpetuation of the marginalisation tradition. This generic trend can be read as the authors privileging their detective’s innate skillset, metonymic connectivity and deductive abilities, while underplaying and belittling EAS and professional investigators. Chapter One establishes the project’s critique of the generic trend by considering parental authors, E. T. A Hoffmann, Edgar Allan Poe, Émile Gaboriau and Wilkie Collins. Reading how these authors instigated and purposed the downplaying demonstrates its founding within detective fiction at the earliest point. By comparing how the authors sidelined and omitted specific EAS and professional investigators, alongside science available at the time, this thesis provides a framework for examining how it continued in detective fiction. In following chapters, the framework established in Chapter One and the theoretical views of Charles Rzepka, Lee Horsley, Stephen Knight and Martin Priestman, are used to discuss how minimising EAS and professional investigators developed into a tradition; and became a generic trend in the recognised detective fiction formula that was used by Sir Arthur Conan Doyle, Freeman Wills Crofts, H. C. Bailey, R. Austin Freeman, Agatha Christie, Ruth Rendell and P. D. James. I then examine how the device transferred to historical detective fiction, using the framework to consider Ellis Peters, Umberto Eco and other selected contemporary authors of historical detective fiction. Throughout, the critical aspect considers how the trivialisation developed and perpetuated through a generic trend. The research concludes that there is a trend embedded within detective and historical detective fiction. One that was created, developed and perpetuated by authors to augment their fictional detective’s innate skillset and to help produce narratives using it is a creative process. It further concludes that the trend can be reimagined to plausibly use EAS and professional investigators in detective and historical detective fiction. The aim of the creative aspect of the project is to employ the research and demonstrate how the tradition can be successfully reinterpreted. To do so, the historical detective fiction novel A Hidden Life uses traditional features of the detective fiction formula to support and strengthen plausible EAS and professional investigators within the narrative. The end result is a historical detective fiction novel. One that proves the thesis conclusion and is fundamentally crafted by the critical research.
218

Identifikace a charakterizace škodlivého chování v grafech chování / Identification and characterization of malicious behavior in behavioral graphs

Varga, Adam January 2021 (has links)
Za posledné roky je zaznamenaný nárast prác zahrňujúcich komplexnú detekciu malvéru. Pre potreby zachytenia správania je často vhodné pouziť formát grafov. To je prípad antivírusového programu Avast, ktorého behaviorálny štít deteguje škodlivé správanie a ukladá ich vo forme grafov. Keďže sa jedná o proprietárne riešenie a Avast antivirus pracuje s vlastnou sadou charakterizovaného správania bolo nutné navrhnúť vlastnú metódu detekcie, ktorá bude postavená nad týmito grafmi správania. Táto práca analyzuje grafy správania škodlivého softvéru zachytené behavioralnym štítom antivírusového programu Avast pre proces hlbšej detekcie škodlivého softvéru. Detekcia škodlivého správania sa začína analýzou a abstrakciou vzorcov z grafu správania. Izolované vzory môžu efektívnejšie identifikovať dynamicky sa meniaci malware. Grafy správania sú uložené v databáze grafov Neo4j a každý deň sú zachytené tisíce z nich. Cieľom tejto práce bolo navrhnúť algoritmus na identifikáciu správania škodlivého softvéru s dôrazom na rýchlosť skenovania a jasnosť identifikovaných vzorcov správania. Identifikácia škodlivého správania spočíva v nájdení najdôležitejších vlastností natrénovaných klasifikátorov a následnej extrakcie podgrafu pozostávajúceho iba z týchto dôležitých vlastností uzlov a vzťahov medzi nimi. Následne je navrhnuté pravidlo pre hodnotenie extrahovaného podgrafu. Diplomová práca prebehla v spolupráci so spoločnosťou Avast Software s.r.o.

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