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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.
121

Tracing the Source of the Elephant and Hippopotamus Ivory from the 14th Century B.C. Uluburun Shipwreck: The Archaeological, Historical, and Isotopic Evidence

Lafrenz, Kathryn Anne 06 April 2004 (has links)
The aim of this study is to establish the provenance of the elephant and hippopotamus ivory recovered from the 14th century B.C. Uluburun shipwreck in order to reconstruct the trade mechanisms and associated social relationships (e.g. diplomacy) operating in the eastern Mediterranean during the Late Bronze Age (LBA). Elephant ivory came either from Northeastern Libya, Southeastern Sudan via Egypt or northwestern Syria during this period. Hippopotamus ivory likewise was obtained from Syria, Palestine, or Egypt. The Uluburun's cargo is reconstructed by the excavator, George Bass, as "royal," and primarily originates from Cyprus and Syro-Palestine. Indeed, LBA trade is largely understood as gift-exchange between ruling elites, thereby reflecting a trade system organized by and for a centralized authority. With the transition to the Iron Age, an identifiable merchant class developed and decentralized trade (relative to the preceding era) under a system of cabotage shipping. If the ivory is shown to derive from several regions instead of a single location, a revision of LBA trade must be fashioned to include ruling elites acting as "merchants" to a larger degree than previously assumed, or the web of social relationships involved in "international" diplomacy as much more intricate. Indeed, the mechanisms of the LBA trade must be established to provide a complete picture of trade, especially since the import and historical data is biased towards a simplistic, centralized trade system. The δ13C, δ15N, and δ18O reflect the climate and vegetation of the area in which a population dwells, so that areas with similar climate/vegetation will produce similar isotopic signatures, though these areas may be geographically seperated. Nevertheless, examining 87Sr/86Sr ratios will distinguish between populations because 87Sr/86Sr mirrors the isotopic signature of the underlying rock, and is sufficiently unique to each region to warrant differentiation. Isotopic ratio analysis (carbon, nitrogen, oxygen, and/or strontium) was conducted on the collagen and apatite components of the ivory using mass spectrometry to differentiate between regions and therefore provide the provenance. Ultimately a source determination utilizing HR-ICP-MS for 87Sr/86Sr was not successful. Future provenance research on ivory should employ TIMS, and consider triangulating 87Sr/86Sr against lead and neodymium isotopes.
122

Privacy-aware Use of Accountability Evidence

Reuben, Jenni January 2017 (has links)
This thesis deals with the evidence that enable accountability, the privacy risks involved in using them and a privacy-aware solution to the problem of unauthorized evidence disclosure.  Legal means to protect privacy of an individual is anchored on the data protection perspective i.e., on the responsible collection and use of personal data. Accountability plays a crucial role in such legal privacy frameworks for assuring an individual’s privacy. In the European context, accountability principle is pervasive in the measures that are mandated by the General Data Protection Regulation. In general, these measures are technically achieved through automated privacy audits. System traces that record the system activities are the essential inputs to those automated audits. Nevertheless, the traces that enable accountability are themselves subject to privacy risks, because in most cases, they inform about processing of the personal data. Therefore, ensuring the privacy of the accountability traces is equally important as ensuring the privacy of the personal data. However, by and large, research involving accountability traces is concerned with storage, interoperability and analytics challenges rather than on the privacy implications involved in processing them. This dissertation focuses on both the application of accountability evidence such as in the automated privacy audits and the privacy aware use of them. The overall aim of the thesis is to provide a conceptual understanding of the privacy compliance research domain and to contribute to the solutions that promote privacy-aware use of the traces that enable accountability. To address the first part of the objective, a systematic study of existing body of knowledge on automated privacy compliance is conducted. As a result, the state-of-the-art is conceptualized as taxonomies. The second part of the objective is accomplished through two results; first, a systematic understanding of the privacy challenges involved in processing of the system traces is obtained, second, a model for privacy aware access restrictions are proposed and formalized in order to prevent illegitimate access to the system traces. Access to accountability traces such as provenance are required for automatic fulfillment of accountability obligations, but they themselves contain personally identifiable information, hence in this thesis we provide a solution to prevent unauthorized access to the provenance traces. / This thesis deals with the evidence that enables accountability, the privacy risks involved in using it and proposes a privacy-aware solution for preventing unauthorized evidence disclosure. Accountability plays a crucial role in the legal privacy frameworks for assuring individuals’ privacy.  In the European context, accountability principle is pervasive in the measures that are mandated by the General Data Protection Regulation. In general, these measures are technically achieved through automated privacy audits. Traces that record the system activities are the essential inputs to those audits. Nevertheless, such traces that enable accountability are themselves subject to privacy risks, because in most cases, they inform about the processing of the personal data. Therefore, ensuring the privacy of the traces is equally important as ensuring the privacy of the personal data. The aim of the thesis is to provide a conceptual understanding of the automated privacy compliance research and to contribute to the solutions that promote privacy-aware use of the accountability traces. This is achieved in this dissertation through a systematic study of the existing body of knowledge in automated privacy compliance, a systematic analysis of the privacy challenges involved in processing the traces and a proposal of a privacy-aware access control model for preventing illegitimate access to the traces.
123

Detrital Zircon U-Pb Geochronology and Provenance Analysis of Sedimentary Rocks in the Paleo-Kuril Arc System (Nemuro and Tokoro Belts), Eastern Hokkaido, Northern Japan. / 北海道東部に分布する古千島弧堆積岩(根室帯および常呂帯)の砕屑性ジルコンU-Pb年代学と後背地解析

Harisma 26 September 2022 (has links)
京都大学 / 新制・課程博士 / 博士(理学) / 甲第24175号 / 理博第4866号 / 京都大学大学院理学研究科地球惑星科学専攻 / (主査)准教授 成瀬 元, 准教授 河上 哲生, 教授 田上 高広 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM
124

Caractérisation de la composition et de la structure des alliages argent-cuivre par ICP-MS avec prélèvement par ablation laser. Application au monnayage carolingien.

Sarah, Guillaume 19 December 2008 (has links) (PDF)
Les monnaies anciennes à base d'argent présentent fréquemment des variations de composition en fonction de la profondeur qui apparaissent principalement suite à leur enfouissement. Une analyse juste de ces échantillons impose de s'affranchir de cette couche superficielle perturbée pour caractériser l'alliage qui n'a pas été affecté par ces modifications. L'analyse par spectrométrie de masse couplée à un plasma inductif avec prélèvement par ablation laser (LA-ICP-MS) permet une approche en profils de concentration qui peut rendre compte des variations de teneur selon la profondeur. Un protocole analytique par LA-ICP-MS a été développé spécifiquement pour les monnaies d'argent, qui permet de visualiser la couche de surface perturbée pour caractériser l'alliage sain lors de l'analyse des éléments majeurs. Les caractéristiques intrinsèques de la méthode LA-ICP-MS ont bénéficié au dosage des éléments mineurs et traces : le nombre d'éléments dosés et les limites de détection très basses permettent de caractériser l'ensemble des constituants de ces alliages. Des méthodes d'analyse complémentaires ont été mises en œuvre pour valider le protocole analytique proposé. <br />Les monnaies d'argent des premiers souverains carolingiens sont les premières à avoir bénéficié des avancées analytiques permises par l'application de la méthode LA-ICP-MS aux échantillons de ce type. L'évolution du titre d'argent de pièces frappées entre 751 et 864 a été étudiée, et corrélée aux données numismatiques et historiques. Des spécificités régionales ou locales du point de vue de la pureté des alliages monétaires ont été observées. L'examen des teneurs en éléments mineurs et traces caractéristiques, susceptibles de témoigner de mélanges ou de mouvements de stocks de métaux précieux, a mis en évidence des particularités de l'argent frappé par certains ateliers monétaires, en particulier celui de Venise.
125

Apport des analyses chimiques multi technique à la compréhension du comportement des éléments traces dans les filières sidérurgiques anciennes. Application aux études de provenance et à la distinction des procédés. Le cas du Pays de Bray normand.

Desaulty, Anne-Marie 24 September 2008 (has links) (PDF)
Afin de déterminer la provenance et le procédé d'élaboration (procédé direct, indirect) d'objet en fer archéologiques, cette étude a cherché à préciser le comportement des éléments traces dans les filières sidérurgiques anciennes. Pour caractériser ce comportement il est nécessaire d'étudier les déchets et produits issus de l'ensemble des deux filières. Rappelons qu'à l'issue de ces procédés anciens, l'objet a la particularité de contenir une partie de scorie, le déchet de la réduction (procédé direct) ou de l'affinage (procédé indirect) sous forme d'inclusion. La taille de ces inclusions et d'une manière générale l'hétérogénéité des échantillons archéologiques ont nécessité pour déterminer leur composition en éléments majeurs et traces d'employer une approche multi échelle (analyses macroscopique, microscopique) requérant l'utilisation d'un grand nombre de techniques d'analyse (EDS, ICP-MS, INAA, LA-ICP-MS). Le corpus étudié est composé d'échantillons provenant de sites archéologiques du Pays de Bray et de réductions expérimentales effectuées à partir de minerai brayon. Celui-ci a également été complété par des spécimens provenant d'autres régions et des données de la base Palsid ont également été utilisées. L'étude de ces échantillons a montré que les scories et donc les inclusions des objets issues de la réduction directe contiennent la plupart des éléments traces présents initialement dans le minerai, alors que les inclusions et scories indirectes sont issues de l'affinage d'une fonte considérablement épurée. Ce sont donc les ordres de grandeur des teneurs de ces éléments (La, Ce, Sm, U...) dans les inclusions des objets, qui permettent de distinguer les deux procédés. Une méthodologie afin de caractériser la signature chimique d'une région géologique a également été établie. La « signature métal » permet de pister le minerai utilisé dans le métal de l'objet (Co/Ni, As/Sb). La «signature déchet » valable uniquement pour des échantillons issus du procédé direct permet de relier les scories, et les inclusions de l'objet fini aux minerais employés (teneurs absolues en éléments majeurs et traces, Si/Al, K/Ca, Mg/Al, K/Al, Sm/Th, Th/U, La/Yb, Y/Yb, Hf/Nb, Eu/Sm, Cs/Rb, Th/Sc). Les « signatures déchet et métal » du Pays de Bray ont été comparées à celles d'autres régions afin de tester leur pouvoir de discrimination. Il apparaît que l'utilisation de ces signatures permet de nettement séparer des échantillons d'origines différentes. Il est ainsi possible d'appliquer cette méthodologie à une problématique historique précise : la détermination des échanges commerciaux entre Rouen et le Pays de Bray au Moyen Âge. Dans ce but des fers de construction des églises rouennaises ont été étudiés. Les « signatures déchets » de ces objets sont très variables d'un échantillon à l'autre et différentes de celle du Pays de Bray. Ces résultats permettent de réfuter l'hypothèse d'une arrivée massive de fer brayon à Rouen au Moyen Âge et plaident pour un approvisionnement des chantiers de la ville fortement lié aux opportunités économiques et politiques, expliquant ainsi la très grande diversité des signatures.
126

A Comparison of Vistrails and Taverna, and Workflow Interoperability

Nyasulu, Jonas January 2009 (has links)
<p>In silico experiments in the field of bioinformatics generate large amounts of data since most of the tasks are done in an exploratory fashion. Workflows are one of the many tools used by scientists to model complex tasks.The interoperability of data generated from these tools plays an important role in improving the efficiency of such tools and also in verifying results from other experiments.We aim to compare workflow systems by integrating bioinformatics data in Vistrails and Taverna. We also look at how the two systems use the open provenance model that has been developed to bring provenance interoperability. We developed web services to perform similar functions of some workflows in Vistrails. With the services we were able to perform most of the tasks we planned using both systems. Differences in how lists of items are processed in the two systems results in differences in how workflows are composed in the two systems. In Taverna there is implicit iteration and Vistrails requires the use of additional modules to perform iteration.There are also differences in the execution times of workflows using web services, with workflows in Taverna taking longer than their counterparts in Vistrails. There are some similarities in the execution pattern of workflows if same workflow is invokedmultiple times, with the first invocation taking longer time than the subsequent ones.</p>
127

Supporting Scientific Collaboration through Workflows and Provenance

Ellqvist, Tommy January 2010 (has links)
<p>Science is changing. Computers, fast communication, and  new technologies have created new ways of conducting research.  For  instance, researchers from different disciplines are processing and  analyzing scientific data that is increasing at an exponential rate.  This kind of research requires that the scientists have access to  tools that can handle huge amounts of data, enable access to vast  computational resources, and support the collaboration of large  teams of scientists. This thesis focuses on tools that help support  scientific collaboration.</p><p>Workflows and provenance are two concepts that have proven useful in  supporting scientific collaboration.  Workflows provide a formal  specification of scientific experiments, and provenance offers a  model for documenting data and process dependencies.  Together, they  enable the creation of tools that can support collaboration through  the whole scientific life-cycle, from specification of experiments  to validation of results.  However, existing models for workflows  and provenance are often specific to particular tasks and tools.  This makes it hard to analyze the history of data that has been  generated over several application areas by different tools.  Moreover, workflow design is a time-consuming process and often  requires extensive knowledge of the tools involved and collaboration  with researchers with different expertise. This thesis addresses  these problems.</p><p>Our first contribution is a study of the differences between two  approaches to interoperability between provenance models: direct  data conversion, and mediation. We perform a case study where we  integrate three different provenance models using the mediation  approach, and show the advantages compared to data conversion.  Our  second contribution serves to support workflow design by allowing  multiple users to concurrently design workflows. Current workflow  tools lack the ability for users to work simultaneously on the same  workflow.  We propose a method that uses the provenance of workflow  evolution to enable real-time collaborative design of workflows.  Our third contribution considers supporting workflow design by  reusing existing workflows. Workflow collections for reuse are  available, but more efficient methods for generating summaries of  search results are still needed. We explore new summarization  strategies that considers the workflow structure.</p><p><img src="data:image/png;base64,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%3D" /></p>
128

The tectonic evolution of northwest Svalbard

Pettersson, Carl Henrik January 2010 (has links)
Svalbard represents the uplifted and exhumed northwest corner of the Barents Sea Shelf. Pre-Carboniferous rocks of Svalbard are divided into the Eastern, Northwestern and Southwestern Terranes, were amalgamated during the Caledonian Orogen and are separated by north-south-trending strike-slip faults. Even though our knowledge of Svalbard’s pre-Carboniferous history has increased dramatically during the last two decades, a major issue remains: Where did the different tectonostratigraphic terranes of Svalbard originate? The answer to this question has profound significance for the entire eastern Laurentian margin, which spans two supercontinent cycles, from the amalgamation and breakup of Rodinia to the amalgamation of Pangea. This thesis constrains the tectonothermal evolution of Svalbard’s Northwestern Terrane (NWT) using ion microprobe and LA-ICP-MS U-Pb zircon geochronology and electron microprobe thermobarometry on metasediments, clastic rocks and granitoids. Detrital zircon age populations of metasediments from the NWT suggests that they (e.g. the Krossfjorden Group) were deposited at c. 1000 Ma in a remnant ocean basin setting outboard the Eastern Grenville Province and were subsequently deformed and intruded by Late Grenvillian granitoids during the final suturing of Rodinia. Thus, a northern branch of the Grenvillian/Sveconorwegian orogeny is not present. This older history of the NWT is extensively overprinted by Late Caledonian deformation and metamorphism, with peak metamorphic conditions of 850 °C at &gt;6 kbars, and subsequent migmatization of the Krossfjorden Group at c. 420 Ma. Based on these data, together with the detrital zircon age population from overlying Late Silurian-Early Devonian clastic rocks, a unifying model is proposed involving fragments from the Grampian orogen and Avalonian crust originally accreted to the Laurentian margin, subsequently transported northwards along sinistral strike-slip faults during Scandian deformation. / At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Submitted. Paper 4: In press.
129

The “Twice-Looted” Archives: Giving Voice to the Long-Silenced Witnesses of World War II

Rosenthal, Jessica S 01 April 2013 (has links)
The “twice-looted” archives refer to a vast body of documents that were looted by Nazi agencies during, and again by Soviet Army units immediately following World War II. The archives were taken in the context of the two most intensive programs of cultural heritage looting in modern history. Their fate remained unknown until the fall of the Soviet Union in 1991. Since then, many efforts have been made to return the documents to their original owners. However, significant obstacles have hindered restitution, leaving a large body of foreign archives in Russia. By connecting the history and current status of the “twice-looted” archives to archival theory and ethical principles on cultural heritage property, this thesis provides a foundation from which to approach archival restitution. The analysis of recent additions to archival theory provides new understandings of archival meaning that may facilitate the restitution of archives displaced by war. Reviewing the details of the archives’ successive seizures leading to their extended residency in the secret “Special Archive” (TsGOA) and discussing restitution developments on national and international levels reveals how exploitation of archives during war violates archival principles. Concluding with specific case studies further illustrates the complex nature of archives and archival meaning and its significance for archival restitution. These discussions reveal the damages that result when archives become targets of war. This in turn, encourages respect for archives and brings attention to the necessity of safeguarding archival heritage.
130

Query Processing in a Traceable P2P Record Exchange Framework

ISHIKAWA, Yoshiharu, LI, Fengrong 01 June 2010 (has links)
No description available.

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