Wireless coverage becomes one of the most significant needs of modern society because of its importance in various applications such as health, distance education, industry, and much more. Therefore, it is essential to provide wireless coverage worldwide, including remote areas, rural areas, and poorly served locations. Recent advances in Low Earth Orbit (LEO) satellite communications provide a promising solution to address these issues in poorly served locations. The thesis studies the performance of a multi-level LEO satellite communication system. More precisely, we model the LEO satellites’ location as Binomial Point Process (BPP) on a spherical surface at n different altitudes given that the number of satellites at each altitude ak is Nk where 1 ≤ k ≤ n and study the distance distribution. The distance distribution is characterized in two categories depending on the location of the observation point: contact distance and the nearest neighbor distance. For that proposed model, we study the user coverage probability by using tools from stochastic geometry for a scenario where satellite earth stations (ESs) with two antennas are deployed on the ground where one of the antennas communicates with the user while the other communicates with LEO satellite. Additionally, we consider a practical use case where satellite communication systems are deployed to increase coverage in remote and rural areas. For that purpose, we compare the coverage probability of the satellite-based communication system in such regions with the coverage probability in case of relying on the nearest anchored base station (ABS), which is usually located at far distances from rural and remote areas.

This study examines the media coverage of the humanitarian situation in Nagorno-Karabakh during a war in the region in 2020. Drawing on the theoretical framework of humanitarian journalism, it first looks at the attention given to the issue within the daily coverage of the war, then turns to explore patterns in the narration of the past events and present situation in feature stories. Two transnational and two regional news outlets are analysed (The Guardian and Al Jazeera, Sputnik and Hürriyet), which all address a global audience through English, but represent different journalistic traditions, are based in countries with diverse involvement in the conflict and proximity to its parties, and have received different amount of attention in the research of humanitarian journalism. The results suggest that the humanitarian crisis in the region received little attention in general within the daily coverage of the war. People of the region were cited rarely in the reports on their condition and were largely absent from the news photographs too. They were depicted in feature articles mostly through their experience of fighting, limiting the diverse contexts of their lives. Although geographical, political and cultural proximity is argued to have affected the reporting by regional outlets, similarities and differences across the two groups were observed too.

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LoRaWAN is a wireless network technology based on the LoRa modulation technology. When planning such a network, it is important to estimate the network’s coverage, which can be done by calculating path loss. To do this, one can utilize empirical models of radio wave propagation. Previous research has investigated the accuracy of such empirical models for LoRa inside cities. However, as the accuracy of these models is heavily dependent on the exact characteristics of the environment, it is of interest to validate these results. In addition, the effect of base station elevation on the models’ accuracy has yet to be researched. Following the problems stated above, the purpose of this study is to investigate the accuracy of empirical models of radio wave propagation for LoRa in an urban environment. More specifically, we investigate the accuracy of the models and the effect of base station elevation on the models’ accuracy. The latter is the main contribution of this study. To perform these investigations, a quantitative experiment was conducted in the city of Jönköping, Sweden. In the experiment a base station was positioned at elevations of 30, 23, and 15m. The path loss was measured from 20 locations around the base station for each level of elevation. The measured path loss was then compared to predictions from three popular empirical models: the Okumura-Hata model, the COST 231-Walfisch-Ikegami model, and the 3GPP UMa NLOS model. Our analysis showed a clear underestimation of the path loss for all models. We conclude that for an environment and setup similar to ours, models underestimate the path loss by approximately 20dB. They can be improved by adding a constant correction value, resulting in a mean absolute error of at least 3,7-5,6dB. We also conclude that the effect of base station elevation varies greatly between different models. The 3GPP model underestimated the path loss equally for all elevations and could therefore easily be improved by a constant correction value. This resulted in a mean absolute error of approximately 4dB for all elevations.

Regression testing is performed after existing source code has been modified to verify that no new faults have been introduced by the changes. Test case selection can be used to reduce the effort of regression testing by selecting a smaller subset of the test suite for later execution. Several criteria and objectives can be used as constraints that should be satisfied by the selection process. One common criteria is function coverage, which can be represented by a coverage matrix that maps test cases to methods under test. The process of generating and evaluating these matrices can be very time consuming for large matrices since their complexity increases exponentially with the number of tests included. To the best of our knowledge, no techniques for reducing execution matrix size have been proposed. This thesis develops a matrix-reduction technique based on analysis of call stack data. It studies the effects of limiting the call stack depth in terms of coverage accuracy, matrix size, and generation costs. Further, it uses a tool that can instrument Java projects using Java’s instrumentation API to collect coverage information on open-source Java projects for varying depth limits of the call stack. Our results show that the stack depth limit can be significantly reduced while retaining high coverage and that matrix size can be decreased by up to 50%. The metric we used to indicate the difficulty of splitting up the matrix closely resembled the curve for coverage. However, we did not see any significant differences in execution time for lower depth limits.

No description available.

The subject of the thesis is to analyze the current status of insurance coverage selected municipalities, analysis and comparison of offers insurance protection of property from commercial insurance community and the proposed changes in the scope of the cover of the municipality.

The objective of the diploma thesis is to compare the actual signal quality in selected locations with the coverage maps of the mobile operator. The places of interest with reduced level of signal strength are located in Brno and its surroundings. Theoretical part of the thesis discusses the issues of geographical information systems, GNSS technologies, mechanisms of signal propagation and mobile applications useful for surveying purposes. The practical part describes the communication with mobile operators, the process of data collection and processing the project using ArcMap software.

En la investigación “La planificación estratégica y su impacto en los indicadores de gestión de calidad en el sector alimentario en Lima Metropolitana en el 2018, tiene como objetivo general establecer cómo la planificación estratégica impacta en los indicadores de gestión de calidad, para lo cual se ha empleado un tipo de estudio no experimental, con diseño descriptivo correlacional. Por ello, se ha elegido una muestra no probabilística de 36 administrativos de las empresas del rubro sector alimentario en Lima Metropolitana como condición se encuentren activos al 2018 para las encuestas realizadas. Se ha tomado en consideración el manejo del tema de la planificación estratégica en el desarrollo de sus actividades y los indicadores de Gestión de calidad. El primero abarca las dimensiones de formulación, evaluación y control de las estrategias, el segundo a las dimensiones de cobertura, eficacia, valoración de ventas, satisfacción al cliente y competitividad. En ambos casos se aplicó un cuestionario en el formato de escala de Likert, también se empleó el diseño descriptivo correlacional para el trabajo, el tipo de investigación fue no experimental de corte transversal. Por otro lado, se realizó entrevistas a expertos en el tema. Para los resultados obtenidos se hizo una prueba mediante la correlación de Spearman, la cual ha permitido señalar que existe relación significativa directamente proporcional (rho=0.0741) entre la Planificación Estratégica con los Indicadores de Gestión de Calidad. Finalmente, se encontró que existe relación significativa directamente proporcional entre la Formulación Estratégica (rho=0.811), la Evaluación de Estrategias (rho=0.606) y Control de la Estrategia (rho=0.645). / In the research “Strategic planning and its impact on quality management indicators in the food sector in Metropolitan Lima in 2018, its general objective is to establish how impactful strategic planning in quality management indicators, for which He has used a non-experimental type of study, with a descriptive correlational design. Therefore, a non-probabilistic sample of 36 administrators of the companies of the food sector in Metropolitan Lima has been chosen as a condition they are active to 2018 for the surveys carried out. The management of the topic of strategic planning in the development of its activities and the indicators of Quality Management have been taken under evaluation. The first covers the dimensions of formulation, evaluation and control of the strategies, the second to the dimensions of coverage, effectiveness, sales valuation, customer satisfaction and competitiveness. In both cases, a questionnaire was applied in the Likert scale format, the descriptive correlational design for the work was also used, the type of research was non-experimental cross-sectional. On the other hand, interviews were conducted with experts on the subject. For the results obtained, a test was carried out using Spearman's correlation, the quality allowed indicating that there is a directly proportional relationship (rho = 0.0741) between the Strategic Planning with the Quality Management Indicators. Finally, it was found that there is a significantly direct proportional relationship between the Strategic Formulation (rho = 0.811), the Evaluation of Strategies (rho = 0.606) and Control of the Strategy (rho = 0.645). / Tesis

Wireless Sensor Networks (WSN) offer a flexible low-cost solution to the problem of event monitoring, especially in places with limited accessibility or that represent danger to humans. WSNs are made of resource-constrained wireless devices, which require energy efficient mechanisms, algorithms and protocols. One of these mechanisms is Topology Control (TC) composed of two mechanisms, Topology Construction and Topology Maintenance. This dissertation expands the knowledge of TC in many ways. First, it introduces a comprehensive taxonomy for topology construction and maintenance algorithms for the first time. Second, it includes four new topology construction protocols: A3, A3Lite, A3Cov and A3LiteCov. These protocols reduce the number of active nodes by building a Connected Dominating Set (CDS) and then turning off unnecessary nodes. The A3 and A3-Lite protocols guarantee a connected reduced structure in a very energy efficient manner. The A3Cov and A3LiteCov protocols are extensions of their predecessors that increase the sensing coverage of the network. All these protocols are distributed -they do not require localization information, and present low message and computational complexity. Third, this dissertation also includes and evaluates the performance of four topology maintenance protocols: Recreation (DGTRec), Rotation (SGTRot), Rotation and Recreation (HGTRotRec), and Dynamic Local-DSR (DLDSR). Finally, an event-driven simulation tool named Atarraya was developed for teaching, researching and evaluating topology control protocols, which fills a need in the area of topology control that other simulators cannot. Atarraya was used to implement all the topology construction and maintenance cited, and to evaluate their performance. The results show that A3Lite produces a similar number of active nodes when compared to A3, while spending less energy due to its lower message complexity. A3Cov and A3CovLite show better or similar coverage than the other distributed protocols discussed here, while preserving the connectivity and energy efficiency from A3 and A3Lite. In terms of network lifetime, depending on the scenarios, it is shown that there can be a substantial increase in the network lifetime of 450% when a topology construction method is applied, and of 3200% when both topology construction and maintenance are applied, compared to the case where no topology control is used.