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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.
81

Software defined networking based resource management and quality of service support in wireless sensor network applications

Letswamotse, Babedi Betty January 2019 (has links)
To achieve greater performance in computing networks, a setup of critical computing aspects that ensures efficient network operation, needs to be implemented. One of these computing aspects is, Quality of Service (QoS). Its main functionality is to manage traffic queues by means of prioritizing sensitive network traffic. QoS capable networking allows efficient control of traffic especially for network critical data. However, to achieve this in Wireless Sensor Networks (WSN) is a serious challenge, since these technologies have a lot of computing limitations. It is even difficult to manage networking resources with ease in these types of technologies, due to their communication, processing and memory limitations. Even though this is the case with WSNs, they have been largely used in monitoring/detection systems, and by this proving their application importance. Realizing efficient network control requires intelligent methods of network management, especially for sensitive network data. Different network types implement diverse methods to control and administer network traffic as well as effectively manage network resources. As with WSNs, communication traffic and network resource control are mostly performed depending on independently employed mechanisms to deal with networking events occurring on different levels. It is therefore challenging to realize efficient network performance with guaranteed QoS in WSNs, given their computing limitations. Software defined networking (SDN) is advocated as a potential paradigm to improve and evolve WSNs in terms of capacity and application. A means to apply SDN strategies to these compute-limited WSNs, formulates software defined wireless sensor networks (SDWSN). In this work, a resource-aware OpenFlow-based Active Network Management (OF-ANM) QoS scheme that uses SDN strategies is proposed and implemented to apply QoS requirements for managing traffic congestion in WSNs. This scheme uses SDN programmability strategies to apply network QoS requirements and perform traffic load balancing to ensure congestion control in SDWSN. Our experimental results show that the developed scheme is able to provide congestion avoidance within the network. It also allows opportunities to implement flexible QoS requirements based on the system’s traffic state. Moreover, a QoS Path Selection and Resource-associating (Q-PSR) scheme for adaptive load balancing and intelligent resource control for optimal network performance is proposed and implemented. Our experimental results indicate better performance in terms of computation with load balancing and efficient resource alignment for different networking tasks when compared with other competing schemes. / Thesis (PhD)--University of Pretoria, 2019. / National Research Foundation / University of Pretoria / Electrical, Electronic and Computer Engineering / PhD / Unrestricted
82

Objektivní analýza dat získaných během měření kvality signálu / Objective analysis of data obtained during quality of service measurements

Dopita, Michal January 2017 (has links)
This thesis is focused on objective analysis of data obtained during quality of service measurements provided by the company O2 Czech Republic Inc. Purpose of this study is mapping of existing methods, resources and ways of measurement. The result of practical part is design of new methodology of measurement for the department RAN Management, which is responsible for measurement of quality of services.
83

Modelování řízeného využití síťových zdrojů v sítích UMTS / Modelling of UMTS network resource control

Bednárik, Ján January 2009 (has links)
The main aim of my master thesis was to get acquainted with the implementation of quality-of-service support methods in UMTS 3G mobile network and the evaluation of these methods in a simulation environment with main interest in the characteristic features of the traffic classes. The impact of the QoS methods available on different service types were verified in the OPNET Modeler simulation environment. I examined mainly the potentials of the model to support the required quality parameters for the connections. The models of typical network applications, available in real UMTS networks, together with two examples of mobile networks, operating voice and video services in combination with standard data services, were defined in this simulation environment. My work also contains the detailed description of configuration parameters fundamental for correct behavior of the simulation models. The simulation also shows the case, when the transport service is rejected due to the lack of network resources. The key parameters of the model are also described and their effect on the service quality with and without QoS control are compared in separate scenarios. Finally, I investigated the effect of mobility of the end stations on the communication process, especially on the duration of a file transmission.
84

Kvalita služby v mobilných sieťach / Quality of Service in Cellular Networks

Spiššák, Filip January 2016 (has links)
This thesis deals with the quality of service (QoS) mechanism in Evolved Packet System (EPS). The basic architecture and characteristics of the EPS are introduced. The concept of QoS is defined. Furthermore, QoS related entities, their functions and corresponding procedures are described. The methodology for measuring and evaluating of end-to-end QoS as seen from a user’s point of view is designed. This methodology is used to measure QoS of experimental cellular network at UTKO FEEC BUT. Finally, configuration change for optimizing the QoS support of experimental cellular network is designed.
85

Optimalizace síťového provozu pomocí OMNeT++ / Optimization of Network Activity by OMNET++

Rybníčková, Eva January 2016 (has links)
This diploma thesis deals with OMNeT++, a simulation tool for network traffic simulations. It describes its installation, basic functions and its use together with an extension INET framework. Further it shows construction of a simple simulation, its parts and analysis of the traffic output. Briefly it explains Quality of Service, which is further practically implemented in visual simulations. The paper further contains two laboratory exercises with model protocols.
86

Reliable Communication of Time- and Security-Sensitive Information over a Single Combat Vehicle Network

Nilsson, Håkan January 2019 (has links)
A common trend, in general as well as in the field of combat vehicles, is the rapidly increasing demand for data network capacity and even more in transferred data. To handle this increased demand, different countries with their armed forces and equipment manufacturers evaluate methods to increase the data transmission capacity in combat vehicles. The different types of transmitted data are of different criticality and have different security demands. An easy solution to this is to have separated networks for each type of traffic, but that is quite expensive and uses a lot of hardware. This thesis focuses on a different solution, with a shared network for all types of data transmissions. This is done by evaluating different types of data networks and add-on protocols and then testing the networks practically with varying transmission rates. In the thesis, all the practical testing is done with data networks according to the Ethernet standard, which is the standard evaluated with a throughput that is high enough for the use case. Ethernet as a standard is not suitable for critical data traffic and therefore add-on protocols for Ethernet to optimize the system for critical data traffic are tested. With these optimizations made, Ethernet can be considered more suitable for critical traffic, but this depends entirely on the system requirements.
87

Los ExPros y su relación con la fidelización de clientes de barberías clásicas, dirigido a hombres de 18 a 35 años residentes de Lima Metropolitana / The ExPros and their relationship with the loyalty of customers of classic barbershops, aimed at men from 18 to 35 years who live in Metropolitan Lima

Lozano Campos, César Antonio 30 November 2019 (has links)
El objetivo de este trabajo de investigación busca analizar de una manera elemental la relación entre los proveedores de experiencia (ExPros) personal y entorno espacial con la fidelización en el sector de barberías de Lima, Perú. El presente trabajo de investigación tiene carácter de una investigación no experimental y de corte transversal. Se utilizaron instrumentos cuantitativos (SPSS) y cualitativos para recolectar información y data numérica representativa. Se realizo un análisis descriptivo sobre el público objetivo que son hombres de 18 a 35 años. Se encontró que entre los dos ExPros investigados, el personal tiene mayor relación con la satisfacción, a comparación que el entorno espacial, siendo la satisfacción la variable intermedia ara llegar a la fidelización del cliente. Finalmente se mencionan las posibles futuras investigaciones que se pueden realizar teniendo en cuenta lo descubierto en el trabajo de investigación elaborado. / The objective of this research work seeks to analyze in an elementary way the relationship between personal experience providers (ExPros) and space environment with loyalty in the barbershop sector of Lima, Peru. This research work has the character of a non-experimental and cross-sectional investigation. Quantitative and qualitative instruments (SPSS) were used to collect information and representative numerical data. A descriptive analysis was carried out on the target audience that are men between 18 and 35 years old. It was found that between the two ExPros investigated, the people has a greater relationship with satisfaction, compared to the spatial environment, with satisfaction being the intermediate variable to reach customer loyalty. Finally, the possible future research that can be carried out is mentioned, taking into account what was discovered in the research work prepared. / Trabajo de investigación
88

Calidad Percibida y Satisfacción del Usuario Hospitalizado en el Servicio de Nutrición de una Clínica de Lima Norte - Perú, 2019 / Perceived Quality and Satisfaction of the Hospitalized User in the Nutrition Service of a Clinic in Lima North - Peru, 2019

Aguilar Gutierrez, Cynthia Elizabeth 18 November 2019 (has links)
Objetivo. Determinar el nivel de satisfacción global basado en la calidad percibida por los usuarios hospitalizados atendidos por el Servicio de Nutrición de una Clínica de Lima Norte, 2019. Material y método. Investigación de diseño descriptivo, observacional, transversal y prospectivo que determina el nivel de satisfacción de la calidad percibida del usuario a través del instrumento SERVPERF que está compuesto de veintidós preguntas distribuidas en sus cinco dimensiones de la calidad (elementos tangibles, fiabilidad, capacidad de respuesta, seguridad y empatía), las cuales son medidas por la escala de Likert de 7 puntos. El muestreo fue por conveniencia y la muestra fue de 75 usuarios hospitalizados, siendo el 58.7% del sexo femenino y el 41.3% del sexo masculino, además el 68.0% son pacientes continuadores y el 82.7% tienen un seguro médico. Resultados. La satisfacción de los usuarios hospitalizados en la Clínica Lima Norte basados en la calidad percibida fue de 87,4%. Respecto a las cinco dimensiones en forma independiente de la calidad percibida se observa que los elementos tangibles son los que mejor calificación reciben con un 92.8% de excelente satisfacción, seguido de las dimensiones de fiabilidad y seguridad con el 90.85% y 90.0% respectivamente de ser excelente, por otro lado la dimensión capacidad de respuesta consiguió una calificación buena con el 84.57 % y la dimensión empatía una calificación regular con el 78.85 % de satisfacción. Conclusión. El nivel de satisfacción global del servicio de nutrición fue buena con un 87.4% de aprobación por los usuarios hospitalizados. / Objective. Determine the level of global satisfaction based on the quality perceived by hospitalized users served by the Nutrition Service of a Clinic in Lima North, 2019. Material and method. Descriptive, observational, transversal and prospective design research that determines the level of satisfaction of the perceived quality of the user through the SERVPERF instrument that is composed of twenty-two questions distributed in its five dimensions of quality (tangible elements, reliability, responsiveness , security and empathy), which are measured by the 7-point Likert scale. The sampling was for convenience and the sample was 75 hospitalized users, being 58.7% female and 41.3% male, in addition 68.0% are continuing patients and 82.7% have medical insurance. Results. The satisfaction of hospitalized users in the Lima Norte Clinic based on perceived quality was 87.4%. Regarding the five dimensions independently of the perceived quality, it is observed that the tangible elements are the ones that receive the best qualification with 92.8% of excellent satisfaction, followed by the dimensions of reliability and safety with 90.85% and 90.0% respectively of being excellent, on the other hand the response capacity dimension achieved a good rating with 84.57% and the dimension empathized a regular rating with 78.85% satisfaction. Conclusion. The level of global satisfaction of the nutrition service was good with 87.4% approval by hospitalized users. / Tesis
89

Calidad en el servicio de los institutos de idiomas en adultos de Lima Metropolitana para estudiar el idioma francés en el año 2019

Cutimbo Gonzalez, Esmeralda, Apcho Tenorio, Claudio Ronald 16 July 2019 (has links)
La calidad del servicio en la actualidad es indispensable para las empresas que quieran ser exitosas, sobre todo, en tiempos donde una noticia viral puede catapultar o hundir a una compañía en cuestión de días. Dicha realidad nos motivó a estudiar este caso aplicando una herramienta de medición de calidad. La tesis propone evaluar la calidad del servicio de instituciones dedicadas a la enseñanza del idioma francés, un idioma hablado por más de 300 millones de personas en todos los continentes y que ha alcanzado un evidente desarrollo en los últimos años. Mediante la herramienta SERVQUAL se estudiarán las brechas entre las expectativas y percepciones de los alumnos activos para que a través de los resultados y conclusiones las instituciones dedicadas a la enseñanza del idioma francés puedan plantear estrategias para mejorar su servicio. Las aplicaciones de este método de medición de la calidad servirán para futuras evaluaciones de las instituciones. / The quality of service today is essential for companies that want to be successful, especially, in times where viral news can catapult or sink a company in a matter of days. This reality motivated us to study this case by applying a quality measurement tool. The thesis proposes to evaluate the quality of the service of the institutions dedicated on the teaching of French languages, a language spoken by more than 300 million people in all continents and that has had an evident development in recent years. Through the SERVQUAL tool, the gaps between the expectations and perceptions of active students will be studied so that through the results and conclusions, the institutions dedicated on teaching the French language can propose strategies to improve their service. The applications of this quality measurement method will work for future evaluations of the institutions. / Tesis
90

Provisioning end-to-end quality of service for real-time interactive video over software-defined networking

Owens II, Harold 09 November 2016 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / This thesis contains four interrelated research areas. Before presenting the four research areas, this thesis presents literature review on Software-Defined Networking (SDN), a network architecture that allows network operator to manage the network using high level abstractions. This thesis presents taxonomy for classifying SDN research. In research first area, this thesis presents Video over Software-Defined Networking (VSDN), a network architecture that selects feasible paths using the network-wide view. This thesis describes the VSDN protocol which is used for requesting service from the network. This thesis presents the results of implementing VSDN prototype and evaluates behavior of VSDN. Requesting service from the network requires developer to provide three input parameters to application programmable interface. The message complexity of VSDN is linear. In research second area, this thesis presents Explicit Routing in Software-Defined Networking (ERSDN), a routing scheme that selects transit routers at the edge of network. This thesis presents the design and implementation of ERSDN. This thesis evaluates the effect of ERSDN on the scalability of controller by measuring the control plane network events-packets. ERSDN reduces the network events in the control plane by 430%. In research third area, this thesis presents Reliable Video over Software-Defined Networking (RVSDN) which builds upon previous work of Video over Software-Defined Networking (VSDN) to address the issue of finding most reliable path. This thesis presents the design and implementation of RVSDN. This thesis presents the experience of integrating RVSDN into ns-3, a network simulator which research community uses to simulate and model computer networks. This thesis presents RVSDN results and analyzes the results. RVSDN services 31 times more requests than VSDN and Multiprotocol Label Switching (MPLS) explicit routing when the reliability constraint is 0.995 or greater. In research fourth area, this thesis presents Multi-Domain Video over Software-Defined Networking (MDVSDN), a network architecture that selects end-to-end network path or path for real-time interactive video applications across independent network domains. This thesis describes the architectural elements of MDVSDN. This thesis presents the results of implementing a prototype of MDVSDN and evaluates the behavior of MDVSDN. The message complexity of MDVSDN is linear. The contribution of this thesis lays the foundation for developing a network architecture that improves the performance of real-time interactive video applications by selecting feasible end-to-end multi-domain path among multiple paths using bandwidth, delay, jitter, and reliability.

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