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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

Newspaper and News Magazine Coverage of the USA PATRIOT Act Before It Was Passed Into Law, September 11, 2001—October 26, 2001

Ravimandalam, Seethalakshmi January 2004 (has links)
No description available.
12

Outdoor to Indoor Coverage in 5G Networks

Rydén, Vilhelm January 2016 (has links)
Outdoor to indoor mobile coverage is evaluated for differentfrequencies in two scenarios, a single building scenario and a cityenvironment. A new model for outdoor to indoor propagation issuggested, connecting existing, highly detailed indoor and outdoorray-tracing propagation models. The model is compared to previous,site specific as well as statistical, propagation models. Resultsconclude that the new model gives higher path gain for edge users inthe single building scenario, whereas results from the city scenarioare inconclusive. Furthermore, results from the single buildingscenario suggest that indoor coverage is possible at 5 GHz and belowfor most buildings, whereas for the city scenario indoor coverage at5 GHz will be possible only for buildings without metally coatedwindows. Achieving indoor coverage at 30 GHz is highly problematicfor all cases, and it is concluded that indoor base stations arenecessary if frequencies of 10 GHz and above are to be used infuture mobile networks. In addition, an indoor analysis is made to verify existing lossper meter indoor models. It is concluded that such models are oftenoptimistic, although their assumption of log-normal shadowing remainvalid, at least for closed offices. Furthermore, the assumption ofloss as a linear function of distance might be unfeasible for higherfrequencies, where a breakpoint in the linear model was observed ata distance of roughly 10 meters.
13

Sites of power, journeys of discovery : place and politics within the hierarchy of the media frame

Couldry, Nicholas Ian January 1998 (has links)
No description available.
14

Coverage-awareness Scheduling Protocols for Wireless Sensor Networks

Fei, Xin 19 September 2012 (has links)
The coverage and energy issues are the fundamental problems which prevent the development of wireless sensor networks. In order to accurately evaluate the monitoring quality (coverage), one needs to model the interactive of sensors, phenomenons and the environment. Furthermore, in collaborative with scheduling algorithm and computer optimization, protocols can improve the overall monitoring quality and prolong the lifetime of network. This thesis is an investigation of coverage problem and its relative applications in the wireless sensor networks. We first discuss the realistic of current boolean sensing model and propose an irregular sensing model used to determine the coverage in the area with obstacles. We then investigate a joint problem of maintaining the monitoring quality and extending the lifetime of network by using scheduling schemes. Since the scheduling problem is NP hard, genetic algorithm and Markov decision process are used to determine an achievable optimal result for the joint problem of coverage-preserving and lifetime-prolong. In order to avoid the cost of centralized or distributed scheduling algorithms, a localized coverage-preserving scheduling algorithm is proposed by exploring the construction process of Voronoi diagram. Besides exploring the coverage characteristic in a static wireless sensor network, we investigate the coverage problem when the mobile elements are introduced into network. We consider the single-hop mobile data gathering problem with the energy efficiency and data freshness concerns in a wireless sensor network where the connectivity cannot be maintained. We first investigate the upper/lower bound of the covering time for a single collector to cover the monitoring area. Through our investigation we show that for a bounded rectangle area a hexagon walk could explore the area more efficiently than a random walk when the edges of area are known. We then propose a virtual force mobile model (VFM) in which the energy consumption for data transmission is modeled as a virtual elastic force and used to guide of mobile collectors to move to optimal positions for energy saving.
15

Value at Risk: GARCH vs. modely stochastické volatility: empirická studie / Value at Risk: GARCH vs. Stochastic Volatility Models: Empirical Study

Tesárová, Viktória January 2012 (has links)
The thesis compares GARCH volatility models and Stochastic Volatility (SV) models with Student's t distributed errors and its empirical forecasting per- formance of Value at Risk on five stock price indices: S&P, NASDAQ Com- posite, CAC, DAX and FTSE. It introduces in details the problem of SV models Maximum Likelihood examinations and suggests the newly devel- oped approach of Efficient Importance Sampling (EIS). EIS is a procedure that provides an accurate Monte Carlo evaluation of likelihood function which depends upon high-dimensional numerical integrals. Comparison analysis is divided into in-sample and out-of-sample forecast- ing performance and evaluated using standard statistical probability back- testig methods as conditional and unconditional coverage. Based on empirical analysis thesis shows that SV models can perform at least as good as GARCH models if not superior in forecasting volatility and parametric VaR. 1
16

Distributed Coverage Control of Multi-Agent System in Convective–Diffusive Time Evolving Environments

Mei, Jian 11 September 2019 (has links)
Using multi-agent systems to execute a variety of missions such as environmental monitoring and target tracking has been made possible by the advances in control techniques and computational capabilities. Communication abilities between agents allow them to coact and execute several coordinated missions, among which there is optimal coverage. The optimal coverage problem has several applications in engineering theory and practice, as for example in environmental monitoring, which belongs to the broad class of resource allocation problems, in which a finite number of mobile agents have to be deployed in a given spatial region with the assignment of a sub-region to each agents with respect to a suitable coverage metric. The coverage metric encodes the sensing performance of individual agent with respect to points inside the domain of interest, and a distribution of risk density. Usually the risk density function measures the relative importance assigned to inner regions. The optimal coverage problem in which the risk density is time-invariant has been widely studied in previous research. The solution to this class of problems is centroidal Voronoi tessellation, in which each agent is located on the centroid of the related Voronoi cell. However, there are many scenarios that require to be modelled by time-varying risk density rather than time-invariant one, as for example in area coverage problems where the environment evolves independently of the evolution for the robotic agents deployed to cover the area. In this work, the changing environment is modeled by a time-varying density function which is governed by a convection-diffusion equation. Mixed boundary conditions are considered to model a scenario in which a diffusive substance (e.g., oil from a leaking event or radioactive material from a nuclear accident) enters the area with convective component from the boundary. A non-autonomous feed- back law is employed whose generated trajectories maximize the coverage metric. The asymptotic stability of the multi-agent system is proven by using Barbalat’s lemma, and then theoretical predictions are illustrated by several simulations that represent idealized scenarios.
17

Making news at Pakaitore: a multi-sighted ethnography

Tait, Sue, n/a January 2000 (has links)
As a public medium and a vehicle of "culture", which frames and comprehends social priorities, relations and identities, news has received scant anthropological attention (Spitulnik 1993). Whanganui Iwi�s occupation of Moutoa Gardens in 1995 was made available to a public as "news". My project reveals a range of exclusions around these mediations, which conjure wider issues regarding the production of representations within (post) colonial contexts. As a contribution to anthropology, my ethnography responds to the limitations of traditional ethnographic praxis, providing a productive response to criticisms of the discipline and revealing the public value of ethnographic sensibilities. Whanganui Iwi believed the Gardens to be the historical site of Pakaitore pa. The area was reclaimed as a marae, shelters were built, the perimeter fenced, and Iwi lived on site for 80 days. The initiative constituted an expression of Iwi�s experiences of exteriority within Wanganui and their frustration with the delay of the Crown�s response to their claims alleging breaches of Treaty of Waitangi. Iwi temporarily inverted their relationship to the Pakeha community by establishing a literal boundary to the marae, which rendered those who were not supportive of Iwi aspirations "outsiders". While access to the marae was controlled, and restrictions were placed on news workers, the only group banned from the marae were the employees of the city�s newspaper, the Wanganui Chronicle. My project details the production of news about Pakaitore, and the attempts of Iwi to control their representation; specifying the role of "location" (both spatial and ideological) in the production of written and photographic accounts (Haraway 1991). I examine how the structures of news production are deployed and contested by news workers, and the manner in which news texts may or may not be "inhabited" by their subjects and public. I compare the journalistic practices of Chronicle workers, prior to and following their ban, with those of out of town newsworkers from press and television. The mechanisms, codes, and values of what makes "good" news structure particular locations for news workers, and this largely precluded conveying the intention and experience of nga Iwi at Pakaitore. This extended to the reports gathered by the reporter for TVNZ (the state owned broadcaster), who, as Iwi whānau, was allowed unfettered access to the marae. Being "the news" interfered with agendas inside the marae. From this location, Pakaitore was about building relationships between hapu and strengthening a sense of community. Hui addressed the status of Iwi within Wanganui, and rangatahi and visitors were educated in tribal history and tikanga. These priorities contest the "outside" perspective that Pakaitore was simply an attempt to antagonise Pakeha authorities. Throughout the course of my fieldwork visual aspects of media representations of Pakaitore were cited by a range of my informants as conveying particular authority. In some contexts this was by way of revealing the "truth" about the threat of protest to social cohesion, while in others it provided evidence for the media�s inability to represent the initiative in a manner that was sympathetic to, or representative of, Iwi whanau. I argue that the privileging of the disembodied visual reproduces myths of "otherness", covering over experiences of embodied "difference" and the history which renders activism intelligible. My project reveals that in Aotearoa/New Zealand, those contesting the Pakeha imaginary of a "post-racist" culture are cast as producing racial disharmony.
18

Coverage-awareness Scheduling Protocols for Wireless Sensor Networks

Fei, Xin 19 September 2012 (has links)
The coverage and energy issues are the fundamental problems which prevent the development of wireless sensor networks. In order to accurately evaluate the monitoring quality (coverage), one needs to model the interactive of sensors, phenomenons and the environment. Furthermore, in collaborative with scheduling algorithm and computer optimization, protocols can improve the overall monitoring quality and prolong the lifetime of network. This thesis is an investigation of coverage problem and its relative applications in the wireless sensor networks. We first discuss the realistic of current boolean sensing model and propose an irregular sensing model used to determine the coverage in the area with obstacles. We then investigate a joint problem of maintaining the monitoring quality and extending the lifetime of network by using scheduling schemes. Since the scheduling problem is NP hard, genetic algorithm and Markov decision process are used to determine an achievable optimal result for the joint problem of coverage-preserving and lifetime-prolong. In order to avoid the cost of centralized or distributed scheduling algorithms, a localized coverage-preserving scheduling algorithm is proposed by exploring the construction process of Voronoi diagram. Besides exploring the coverage characteristic in a static wireless sensor network, we investigate the coverage problem when the mobile elements are introduced into network. We consider the single-hop mobile data gathering problem with the energy efficiency and data freshness concerns in a wireless sensor network where the connectivity cannot be maintained. We first investigate the upper/lower bound of the covering time for a single collector to cover the monitoring area. Through our investigation we show that for a bounded rectangle area a hexagon walk could explore the area more efficiently than a random walk when the edges of area are known. We then propose a virtual force mobile model (VFM) in which the energy consumption for data transmission is modeled as a virtual elastic force and used to guide of mobile collectors to move to optimal positions for energy saving.
19

Information Theoretic Aspects of Wireless Networks with Coverage Constraint

Mirghaderi, Seyed Reza January 2007 (has links)
A wireless multicast network with a stringent decoding delay constraint and a minimum coverage requirement is characterized when the fading channel state information is available only at the receiver side. In the first part, the optimal expected rate achievable by a random user in the network is derived in a single antenna system in terms of the minimum multicast requirement in two scenarios: hard coverage constraint and soft coverage constraint. In the first case, the minimum multicast requirement is expressed by multicast outage capacity while in the second case, the expected multicast rate should satisfy the minimum requirements. Also, the optimum power allocation in an infinite layer superposition code, achieving the highest expected typical rate, is derived. For the MISO case, a suboptimal coding scheme is proposed, which is shown to be asymptotically optimal, when the number of transmit antennas grows at least logarithmically with the number of users in the network. In the second part, a joint source-channel coding scheme is motivated, where a multi-resolution Gaussian source code is mapped to a multi-level channel code. In this part, the hard and soft coverage constraints are defined as maximum outage multicast distortion and maximum expected multicast distortion, respectively. In each scenario, the minimum expected distortion of a typical user is derived in terms of the corresponding coverage constraint. The minimization is first performed for the finite state fading channels and then is extended to the continuous fading channels.
20

Evaluation Integrated Mass Drug Administrations (MDA) for Neglected Tropical Diseases, in Koza District, Cameroon

Conrardy, Christina B 20 December 2012 (has links)
Health education and preventive chemotherapy are main strategies to control or eliminate neglected tropical diseases (NTDs) such as lymphatic filariasis (LF), trachoma, onchocerciasis, schistosomiasis (SCH), and soil-transmitted helminthiasis (STH). Integrated MDA for LF, onchocerciasis, SCH, STH, and trachoma were organized in the Koza district of Cameroon from July to August 2011. Ivermectin (IVM) and albendazole (ALB) were distributed for LF to the entire population except pregnant or lactating women, children <90 cm in height, and the severely ill. Azithromycin was distributed at least one week after the LF MDA to all persons older than 6 months of age. Praziquantel (PZQ), targeting school age children (SAC), was only distributed in schools. In order to validate reported coverage and assess the knowledge and attitude of the population towards NTDs and MDAs, an independent coverage and Knowledge, Attitudes, and Practice (KAP) survey was administered. The WHO recommended population based 30-cluster coverage survey was implemented. Clusters were selected by Probability Proportional to Estimated Size and in each cluster, 10 houses were selected using the improved expanded program on immunization random walk. Coverage questions were administered by trained interviewers to each person living in selected houses and KAP questions were asked to a randomly selected adult in the house. A total of 1301 persons participated in the coverage survey and 149 adults answered the KAP questions. The survey coverage estimates for IVM /ALB and azithromycin are 76.9% (95% CI 72.0-81.9), 86.8% (95% CI 80.9-92.7), respectively, while the reported coverage is 80.3% and 93%, respectively. The survey coverage estimated for PZQ among SAC is 39.9% (95% CI 30.7-49.1), reported coverage is unknown. There was no significant association between participation in the MDA and age, gender, or knowing the disease. SAC who attended school were 269 times as likely to have taken PZQ and 3 times as likely to have taken LF drugs as SAC not attending school. Less than 50% of respondents had heard of LF and only 31.8% could mention at least one LF symptom. More than 70% of respondents had heard of STH, SCH, and trachoma, but only 52.3%, 40%, 30%, respectively, knew at least one way to prevent or treat STH, SCH, and trachoma. Despite low or incorrect knowledge of LF, SCH, STH, and trachoma, overall, MDA coverage was good except for the PZQ which was only distributed in school.

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