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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.
11

A Study of the Turkmen Dialects of Afghanistan

Rasekh, Muhammad Salih 10 July 2017 (has links)
Mit dieser Studie wird der erstmalige Versuch unternommen, die turkmenischen Dialekte Afghanistans durch die Erhebung von umfangreichem Primärmaterial zu dokumentieren und ihre phonologischen, morphologischen und lexikalischen Merkmale kontrastiv zu beschreiben. Durch die Erfassung und Beschreibung soziolinguistischer Gegebenheiten wird darüber hinaus die Einbettung dieser Idiome in die sprachliche Landschaft Afghanistans zu erklären versucht. Die turkmenischen Dialekte Afghanistans zerfallen in zwei Großgruppen, die xāliṣ- und nāxāliṣ-Dialekte. Die Binnendifferenzierung koinzidiert, wie die Studie erbracht hat, weitestgehend, wenn auch nicht ausnahmslos, mit ethnischer Differenzierung (und nicht etwa mit geographischer Distribution). Das wichtigste Differenzierungsmerkmal der turkmenischen Dialekte ist die Phonologie; entsprechend viel Aufmerksamkeit widmet die Studie den phonologischen Merkmalen. Morphologisch sind die Dialekte dagegen weitgehend einheitlich, nur die nāxāliṣ-Dialekte zeigen gewisse signifikante Abweichungen; die Verbalmorphologie, auf deren Bearbeitung aus Kapazitätsgründen verzichtet werden musste, verspricht diesbezüglich allerdings weitere interessante Erkenntnisse. Bezüglich der Lexik wurden beispielhafte semantische Felder (z.B. Verwandtschaftsterminologie) bearbeitet, die nur wenige, aber aussagekräftige und teilweise unerwartete Abweichungen aufweisen. Die turkmenischen Dialekte Afghanistans zeigen soziolinguistisch betrachtet auffällige Verschiedenheiten entlang Gender-, Alters-, Standes- und geographischen Trennlinien. Die Studie erläutert außerdem die Position des Turkmenischen gegenüber dem generell dominanten Dari, dem in der Verbreitungsregion omnipräsenten Usbekischen, dem lokal bedeutenden Pašto und dem Türkeitürkischen, das durch seine mediale Präsenz und infolge von Migration angesichts der großen linguistischen Nähe zunehmend an Bedeutung gewinnt. Indem die Arbeit für alle thematisierten Phänomene umfangreiches Belegmaterial aus der Feldforschung vorlegt, ermöglicht sie nicht nur die Überprüfung der eigenen Befunde, sondern eröffnet vor allem auch für die derzeit kaum zugängliche Region Nordafghanistan weitere Arbeitsfelder für sprachwissenschaftliche Studien. / The Turkmen dialects of Afghanistan have for the first time been made the object of a special comprehensive study which, on the basis of rich primary materials collected from the field, is investigating their phonological, morphological and lexical features. The study is supplemented with sociolinguistic observations which help positioning the Turkmen dialects within the linguistic universe of Afghanistan today. The Turkmen dialects of Afghanistan basically fall into two major groups which in this study, following the emic denominations, are being called xāliṣ und nāxāliṣ dialects. As the study demonstrates, the dialects are almost without exceptions deliminated not along geographical or regional lines but along the major ethnic delimitations. Phonology is the prime marker of dialect delimitation. Consequently, this study pays particular attention to phonological markers. On the other hand there is only little variation in morphology; only the nāxāliṣ dialects do not completely share these paradigms. Verbal morphology, which appears to depict more variation, has for reasons of feasibility not been included in this study. In the lexicology chapter several exemplary subfields of the Turkmen dialect lexicon (such as kinship terminology) are investigated in depth; this part of the study yields interesting, partly unexpected results. The sociolinguistic chapters, which for capacity reasons are again dealing with selected aspects only, focus on the role of gender, age, social status and regional attribution of the speakers as markers of distinction. The position of the Turkmen dialects within the wide and complex spectrum of high and low prestige idioms present in North Afghanistan is measured against the supreme language of interethnic communication, education and the media (Dari) as well as the omnipresent language of regional communication (Uzbek), and neighboring Pashto; due to migration, educational and business contacts and the media, and favored by its linguistic closeness to Turkmen, the Turkish language of Turkey has recently become an important contact language as well. All phenomena investigated in this study are derived from a wealth of field materials. By presenting many of these while illustrating the features discussed in the chapters, this study provides fresh material from an almost inaccessible area for linguistic investigations beyond the scope of this book.
12

A Scheduling Scheme for Efficient Wireless Charging of Sensor Nodes in WBAN

Rabby, Md Khurram M., Alam, Mohammad Shah, Shawkat, Shamim Ara, Hoque, Mohammad A. 14 August 2017 (has links)
This paper presents a scheduling algorithm for point to point wireless power transfer system (WPTS) to sensor nodes of wireless body area networks (WBAN). Since the sensors of wireless body area networks are continuously monitoring and sending data to remote central unit, power crisis for these sensor nodes degrades the data transfer of patient monitoring system. Although energy harvesting from ambient sources using electromagnetic induction enhances the longevity of sensor performance, continuous operation in the primary side decreases the overall efficiency. With such paradigm in sight, a framework is proposed for increasing the primary battery longevity and reducing the transmission loss, inductive power is transmitted from primary to secondary unit using medium access control (MAC) protocols for underlying the centralized scheduling opportunity in a collision free scheme for channel access of rare yet critical emergency situation. In a preliminary study, the proposed scheduling for charging sensor nodes in a wireless body area network (WBAN) is evaluated in a case consideration.
13

Associated Sulfide Minerals in Thiosulfate Leaching of Gold: Problems and Solutions

Xia, Chen 01 April 2010 (has links)
The effects of some associated minerals on thiosulfate gold leaching were studied through thermodynamic analysis and leaching experiments on composite ore samples containing various minerals and a reference silicate gold ore. In the leaching test on the reference gold ore, about 93% of gold was extracted within 3.0 hours. The presence of various amount of pyrite, pyrrhotite, chalcopyrite, arsenopyrite, chalcocite, bornite, and some lead species, has significant detrimental effects. Under reduced oxygen conditions, the thiosulfate consumptions could be significantly reduced. High gold extractions (i.e. >= 90%) were observed in the leaching tests with reduced dissolved oxygen (i.e., 0.7% oxygen in the supplied gas) in the absence or in the presence of sulfide minerals such as pyrite, pyrrhotite, arsenopyrite and chalcopyrite. High copper concentration and a pre-aeration step was also found to largely increase the gold extractions under such conditions. Thiosulfate-copper-ethylenediamine system was found effective in the leaching of gold. The leaching kinetics was significantly slower than that of the conventional thiosulfate-copper-ammonia leaching. The consumption of thiosulfate, however, was largely reduced. This leaching system worked effectively on the reference gold ore within a wider pH range (e.g., 6-11), with or without ammonia. The presence of ammonia in a low concentration improved the leaching rate but also increase the consumption of thiosulfate. Comparable gold extractions were observed in the leaching of the composite ores containing various sulfide minerals, such as pyrite, pyrrhotite, chalcocite, galena and chalcopyrite. The leaching of gold in the presence of iron sulfides was also improved by applying chemical additives, such as, carbonate, calcium, galena, phosphate, and additional hydroxide anion. It is proposed that these additives either passivated the harmful surface of sulfide minerals or masked some detrimental aqueous species. Finally, some improved leaching methods concluded in this study were applied on a few industrial ore samples in order to demonstrate the effectiveness of these methods. It was found that by comprehensively applying these improved thiosulfate leaching strategies, satisfactory gold extractions and thiosulfate consumption results were archived on these ores. / Thesis (Ph.D, Mining Engineering) -- Queen's University, 2008-09-18 11:48:38.672
14

Energy And Channel-Aware Power And Discrete Rate Adaptation And Access In Energy Harvesting Wireless Networks

Khairnar, Parag S 05 1900 (has links) (PDF)
Energy harvesting (EH) nodes, which harvest energy from the environment in order to communicate over a wireless link, promise perpetual operation of wireless networks. The primary focus of the communication system design shifts from being as energy conservative as possible to judiciously handling the randomness in the energy harvesting process in order to enhance the system performance. This engenders a significant redesign of the physical and multiple access layers of communication. In this thesis, we address the problem of maximizing the throughput of a system that consists of rate-adaptive EH nodes that transmit data to a common sink node. We consider the practical case of discrete rate adaptation in which a node selects its transmission power from a set of finitely many rates and adjusts its transmit power to meet a bit error rate (BER) constraint. When there is only one EH node in the network, the problem involves determining the rate and power at which the node should transmit as a function of its channel gain and battery state. For the system with multiple EH nodes, which node should be selected also needs to be determined. We first prove that the energy neutrality constraint, which governs the operation of an EH node, is tighter than the average power constraint. We then propose a simple rate and power adaptation scheme for a system with a single EH node and prove that its throughput approaches the optimal throughput arbitrarily closely. We then arrive at the optimal selection and rate adaptation rules for a multi-EH node system that opportunistically selects at most one node to transmit at any time. The optimal scheme is shown to significantly outperform other ad hoc selection and transmission schemes. The effect of energy overheads, such as battery storage inefficiencies and the energy required for sensing and processing, on the transmission scheme and its overall throughput is also analytically characterized. Further, we show how the time and energy overheads incurred by the opportunistic selection process itself affect the adaptation and selection rules and the overall system throughput. Insights into the scaling behavior of the average system throughput in the asymptotic regime, in which the number of nodes tend to infinity, are also obtained. We also optimize the maximum time allotted for selection, so as to maximize the overall system throughput. For systems with EH nodes or non-EH nodes, which are subject to an average power constraint, the optimal rate and power adaptation depends on a power control parameter, which hitherto has been calculated numerically. We derive novel asymptotically tight bounds and approximations for the same, when the average rate of energy harvesting is large. These new expressions are analytically insightful, computationally useful, and are also quite accurate even in the non-asymptotic regime when average rate of energy harvesting is relatively small. In summary, this work develops several useful insights into the design of selection and transmission schemes for a wireless network with rate-adaptive EH nodes.
15

Poets on the Hill: A Contemporary Exploration of Canadian Political Poetry in English

DesRoches, Nicolas N. 10 1900 (has links)
<p>In this thesis, I investigate Canadian poetry that is explicitly about the political (politicians, political parties, or political policies) written in English. I begin by defining political poetry and its aims in Canada and then progress through an examination of three collections of poetry and one poem: <em>The Blasted Pine</em>; <em>Howl Too, Eh?</em>; and <em>Rogue Stimulus</em>. This allows for a comprehensive look at how political poetry has evolved in Canada from a pointed and critical genre that aims to mock and argue to a more subtle, playful genre that utilizes parody and wit. It also demonstrates the evolution and complication of voice in political poetry, given that each poem contains the voice of the poet, the speaker, the public, and the political.</p> <p>I argue that political poetry in Canada is not poetry as dissent, protest, or witness, but rather poetry as inquiry/commission (in the political sense). This definition relies on the fact that Canadian political poetry seeks to ascribe accountability for political actions and decisions and utilizes the poet as spokesperson, speaking for the public to the political (and the public in turn). Canadian political poetry hence arises out of a demand from the public, much like political inquiries do, and through the satirical use of politically correct language and explicit political references calls for action from the political sphere and the public. I further argue that poetry as inquiry also comments on the public itself (including the author/speaker as a member of that public) and that political poetry is transideological.</p> / Master of Arts (MA)
16

Diversité microbienne et multifonctionnalité des écosystèmes forestiers boréaux du Québec

Giguère-Tremblay, Roxanne January 2020 (has links) (PDF)
No description available.
17

Photoionisationsmassenspektroskopie primärer Photolyseprodukte / Photoionization mass spectrometry of primary photofragments

Schürmann, Max Christian 29 June 2001 (has links)
A new experimental approach is reported that focuses on photoionization mass spectrometry of primary photofragments. Photodissociation of molecules and radicals is carried out by using a tunable, pulsed dye laser. Nascent photofragments are subsequently photoionized by time-correlated vacuum-ultraviolet (VUV) radiation, so that only single-photon ionization occurs. Several experimental approaches are used in order to optimize pulsed radiation sources in the VUV that are suitable for pump-probe experiments. Laser systems that rely on frequency tripling in suitable non-linear media are used as an intense VUV radiation source of narrow bandwidth and limited tuning range. Monochromatized laser-produced plasma radiation is also used, which provides tunable VUV radiation throughout the entire VUV energy regime (8-25 eV). Ionized photofragments are finally detected by time-of-flight mass spectrometry. This experimental approach is used in order to investigate the following issues: * Absolute photoionization cross sections of atomic and molecular photofragments are derived from photoionization mass spectrometry. This is shown for the photolysis of chlorine dioxide (OClO), chlorine monoxide (ClO) and ozone (O3). The latter species generates O(1D), so that photoionization and autoionization of this excited species was studied for the first time. * Quantum states and quantum state distributions are derived from photoion yields of primary photofragments in order to characterize photodissociation processes. This is shown for the predissociation of OClO, which yields vibrationally excited ClO in its electronic ground state. * Branching ratios and quantum yields of competing photochemical pathways are determined from photoionization mass spectrometry. The accuracy of this approach is superior to other techniques. These investigations allowed us to investigate photolysis processes of molecules and radicals that are of significant importance with respect to recent issues of atmospherical photoprocesses, such as polar ozone depletion.
18

Primäre Photoprozesse atmosphärischer Spurengase / Primary photoprocesses of atmospheric trace gases

Plenge, Jürgen 09 January 2003 (has links)
Halogenhaltigen atmosphärischen Spurengasen wird eine Schlüsselrolle bei lokalen, regionalen und globalen Veränderungen der Erdatmosphäre zugesprochen. Die Photolyse dieser Stoffe durch ultraviolette Strahlung der Sonne führt zum Eintrag reaktiver Atome und Radikale in die Atmosphäre. Dies betrifft vor allem den stratosphärischen Ozonabbau, der nach heutigem Kenntnisstand durch Reaktionszyklen katalysiert wird und bei dem die Photolyse halogenhaltiger Spurengase an zentraler Stelle beteiligt ist. Im Rahmen dieser Arbeit wurden primäre Photoprozesse halogenhaltiger atmosphärischer Spurengase in Laborexperimenten charakterisiert. Dabei bestand das Ziel in der Bestimmung von primären Quantenausbeuten und Verzweigungsverhältnissen konkurrierender Photolysekanäle. Hierfür wurde ein neuartiger experimenteller Ansatz genutzt, der die folgenden Komponenten beinhaltet: (a) Photolyse der Spurengase durch gepulste ultraviolette Laserstrahlung unter stoßfreien Bedingungen, (b) Ein-Photon-Ionisation der neutralen Photolyseprodukte mittels durchstimmbarer Vakuum-UV-Strahlung und (c) Identifizierung der gebildeten Photoprodukt-Ionen durch Flugzeit-Massenspektrometrie. Dieser Ansatz ermöglicht die Identifizierung aller gebildeten Photolyseprodukte, die Bestimmung des Anregungszustandes der Photoprodukte durch Ausnutzung von Autoionisationsprozessen und die Bestimmung von Verzweigungsverhältnissen und Quantenausbeuten konkurrierender Photoprozesse.Im einzelnen wurden die atmosphärischen Spurengase Chlormonoxid (ClO) und sein Dimer (Cl2O2), Nitrylchlorid (ClNO2), Brommonoxid (BrO) und Bromnitrat (BrONO2) untersucht. Die Resultate können zur Verfeinerung atmosphärischer Modelle und deren Prognosefähigkeit beitragen. Insbesondere können die Ergebnisse auch einen Beitrag zur zuverlässigen Interpretation von Ergebnissen aus Feldstudien leisten.
19

Network layer reliability and security in energy harvesting wireless sensor networks

Yang, Jing 08 December 2023 (has links) (PDF)
Wireless sensor networks (WSNs) have become pivotal in precision agriculture, environmental monitoring, and smart healthcare applications. However, the challenges of energy consumption and security, particularly concerning the reliance on large battery-operated nodes, pose significant hurdles for these networks. Energy-harvesting wireless sensor networks (EH-WSNs) emerged as a solution, enabling nodes to replenish energy from the environment remotely. Yet, the transition to EH-WSNs brought forth new obstacles in ensuring reliable and secure data transmission. In our initial study, we tackled the intermittent connectivity issue prevalent in EH-WSNs due to the dynamic behavior of energy harvesting nodes. Rapid shifts between ON and OFF states led to frequent changes in network topology, causing reduced link stability. To counter this, we introduced the hybrid routing method (HRM), amalgamating grid-based and opportunistic-based routing. HRM incorporated a packet fragmentation mechanism and cooperative localization for both static and mobile networks. Simulation results demonstrated HRM's superior performance, enhancing key metrics such as throughput, packet delivery ratio, and energy consumption in comparison to existing energy-aware adaptive opportunistic routing approaches. Our second research focused on countering emerging threats, particularly the malicious energy attack (MEA), which remotely powers specific nodes to manipulate routing paths. We developed intelligent energy attack methods utilizing Q-learning and Policy Gradient techniques. These methods enhanced attacking capabilities across diverse network settings without requiring internal network information. Simulation results showcased the efficacy of our intelligent methods in diverting traffic loads through compromised nodes, highlighting their superiority over traditional approaches. In our third study, we developed a deep learning-based two-stage framework to detect MEAs. Utilizing a stacked residual network (SR-Net) for global classification and a stacked LSTM network (SL-Net) to pinpoint specific compromised nodes, our approach demonstrated high detection accuracy. By deploying trained models as defenses, our method outperformed traditional threshold filtering techniques, emphasizing its accuracy in detecting MEAs and securing EH-WSNs. In summary, our research significantly advances the reliability and security of EH-WSN, particularly focusing on enhancing the network layer. These findings offer promising avenues for securing the future of wireless sensor technologies.
20

Requisitos de segurança no trabalho e sua influência na formação de preços de serviços de construção civil: estudo de caso em uma empresa petroquímica

Assunção, Ana Maria Farhá January 2006 (has links)
p. 1-137 / Submitted by Santiago Fabio (fabio.ssantiago@hotmail.com) on 2013-03-07T18:21:48Z No. of bitstreams: 1 5555.pdf: 13354600 bytes, checksum: a877fa17734885ff9617d782a7473128 (MD5) / Approved for entry into archive by Tatiana Lima(tatianasl@ufba.br) on 2013-03-14T19:17:54Z (GMT) No. of bitstreams: 1 5555.pdf: 13354600 bytes, checksum: a877fa17734885ff9617d782a7473128 (MD5) / Made available in DSpace on 2013-03-14T19:17:54Z (GMT). No. of bitstreams: 1 5555.pdf: 13354600 bytes, checksum: a877fa17734885ff9617d782a7473128 (MD5) Previous issue date: 2006 / A transformação nas organizações na busca da excelência de gestão fez evoluir a gestão dos Sistemas de Saúde, Higiene e Segurança no Trabalho - SSHMA que passaram a atuar de forma sistêmica nas empresas envolvendo também os fornecedores de serviços contratados. A análise do que ocorre nos custos dos serviços contratados após a introdução dos requisitos de Saúde, Higiene e Segurança do Trabalho, e em paralelo à verificação dos benefícios e avanços obtidos nos níveis de redução de acidentes, torna-se relevante para as empresas contratantes na consolidação dos seus sistemas de SSHMA. Da mesma forma torna-se relevante para as empresas de construção civil contratadas, verificar em que medida um padrão de atuação em SSHMA, diferenciado em relação seu setor usual de atuação, influencia a competitividades destas empresas para atuar como fornecedoras no mercado do Pólo Petroquímico de Camaçari. Esta pesquisa verifica, no período de 2000 a 2004, numa empresa petroquímica situada no Pólo de Camaçari, ganhadora do Prêmio Pólo de Segurança por duas vezes neste período, o reflexo na ocorrência de acidentes e nos preços dos serviços de Construção Civil realizados, com a introdução de requisitos de segurança nos contratos. / Salvador

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