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Modeling and analysis of customer premise equipments registration process in IEEE 802.22 WRAN cellAfzal, Humaira, Awan, Irfan U., Mufti, Muhammad R., Sheriff, Ray E. 30 July 2014 (has links)
No / The development of the IEEE 802.22 standard is aimed at providing broadband access in rural areas by effectively utilizing the unused TV band, provided no harmful interference is caused to the incumbent operation. The motivation behind TV band selection is of having lower frequencies compared to other licensed bands, which, therefore, results in lower propagation path loss. Due to this quality, the spectral power density of the radio signal reduces slowly, which results in a high coverage area. Further, it has been observed that many TV channels largely remain unoccupied, as most households and businesses rely on cable and satellite TV services. This is the first international standard for a wireless regional area network (WRAN) based on cognitive radio technologies. This standard provides both PHY and MAC layer functionalities in an infrastructure based network for communication between customer premise equipments (CPEs) through a base station (BS). The Spectrum Manager is the central part of the BS, which plays a significant role in maintaining spectrum availability information, channel selection, channel management, scheduling quiet periods for spectrum sensing, accessing to the database and implementing IEEE 802.22 policies. A WRAN can particularly accommodate up to 512 CPEs in a cell. Contention may occur during initial ranging, periodic ranging, bandwidth request and urgent coexistence situation notification. The medium access control (MAC) incorporates several schemes to control contention between CPEs within a cell and overlapping cells sharing the same channel. A CPE has to make decision to resolve collisions in the upstream direction. In the case of initial ranging and periodic ranging, code division multiple access (CDMA) is employed to resolve collisions. For bandwidth and UCS notification, either a CDMA or exponential time backoff approach can be applied for collision resolution. This paper presents the analytical framework to evaluate the number of active CPEs in a cognitive radio network, It is important to note that when the arrival rate becomes equal to the service rate, the active CPEs curve attains a constant value. Further, the active CPEs length is highly dependent on service rate. The different special cases have been addressed and the effectiveness of the proposed framework has been validated through various evaluation results.
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Modelling and analysis of dynamic spectrum sharing in cognitive radio based wireless regional area networks : modelling and performance evaluation of initialization and network association of customer premise equipments with the base station in cognitive radio based IEEE 802.22 wireless regional area networksAfzal, Humaira January 2014 (has links)
The development of the IEEE 802.22 standard is aimed at providing broadband access in rural areas by effectively utilizing the unused TV band, provided no harmful interference is caused to the incumbent operation. This thesis presents the analytical framework to evaluate the number of active customer premise equipments (CPEs) in a wireless regional area network. Initial ranging is the primary process in IEEE 802.22 networks for CPEs to access the network and establish their connections with the base station (BS). A comprehensive analysis of initial ranging mechanism is provided in this work and initial ranging request success probability is derived based on the number of contended CPEs and the initial contention window size. Further, the average ranging success delay is derived for the maximum backoff stages. The collision probability is highly dependent on the size of the initial contention window and the number of contended CPEs. To keep it at a specific level, it is necessary for the BS to schedule the required size of the initial contention window to facilitate the maximum number of CPEs to establish their connections with reasonable delay. Therefore, the optimized initial window size is proposed that meets the collision probability constraint for a particular number of contended CPEs. An analytical model is also developed to estimate the ranging request collision probability depending upon the size of initial contention window and the number of contended CPEs. Moreover, this approximation provides the threshold size for contention window to start the initial ranging process in the IEEE 802.22 network.
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O direito concursal das sociedades cooperativas e a lei de recuperação de empresas e falência / Cooperative bankrupty system and the Brazilian bankruptcy lawMaffioletti, Emanuelle Urbano 25 May 2010 (has links)
A tese parte da análise jurídica do concurso das sociedades cooperativas para abordar as disciplinas concursais de insolvência civil, recuperação de empresas e falência, bem como as normas de liquidação aplicáveis às cooperativas no direito brasileiro e comparado. O direito concursal hodierno dispõe de mecanismos recuperativos em caso de crise financeira, e liquidatórios, com normas que primam pela eficiência dos institutos do direito concursal e pela continuação da atividade produtiva, com o fim de beneficiar o credor, devedor e a coletividade. Tende-se a adotar o princípio de unidade legal, de sistema e de disciplina, com pressuposto subjetivo unificado, abrangendo todos os devedores, inclusive as sociedades cooperativas, que quando organizadas como empresas são empresárias de economia social, com natureza jurídica e estrutura que beneficiam a coletividade. O Brasil não adota o princípio da unidade, nem reconhece as sociedades cooperativas como empresas, com a exclusão das cooperativas da lei de recuperação e falências, o que fere as orientações internacionais de incentivo e de tratamento não discriminatório às sociedades cooperativas e surge como mais um obstáculo ao seu desenvolvimento no Brasil. Este estudo teórico-descritivo subdivide-se em três capítulos: o primeiro aborda a doutrina e a normativa do direito concursal com enfoque na sociedade cooperativa, analisando a evolução do direito concursal, os pressupostos subjetivos e os institutos do direito concursal brasileiro, inclusive os aplicáveis às sociedades cooperativas; o segundo aprofunda o estudo da sociedade cooperativa como empresa de economia social para demonstrar a sua realidade econômica empresarial e as suas características estruturais, além de as orientações internacionais sobre a promoção da cooperativa; e o terceiro avalia a adequação do direito concursal das cooperativas no Brasil e formula proposições sobre a matéria. A relação teoria e prática tem como base as decisões judiciais existentes sobre a matéria. / The thesis begins with the legal analysis of the bankruptcy of cooperative societies to address the legal types of bankruptcy non-commercial entities insolvency system (insolvência civil), companies recovery system and bankruptcy and the liquidation rules applicable to cooperatives under Brazilian law and comparative law. The bankruptcy law nowadays has recovery mechanisms in cases of financial crisis and liquidation. It presents rules that aim at efficiency and at the continuity of the production, in order to benefit creditors, debtors and the community. There is a tendency to adopt the legal unit principle, the system principle and the discipline principle, with a unified subjective premise that covers all debtors, including cooperative societies. When organized as companies, these societies are social economy entrepreneurs, whose juridical nature and structure benefit the community. Brazil does not adopt the legal unit principle and does not recognize cooperative societies as companies, with the exception of the cooperatives covered by the recovery and bankruptcy law. This fact constitutes a disagreement in relation to international orientations of promotion and non-discriminatory treatment to cooperative societies and arises as an obstacle to the development of these societies in the country. The theoretical-descriptive study is divided into three chapters: the first one presents the doctrine and the rules related to bankruptcy law focusing the aspects of cooperative societies and analyzing the evolution, the subjective premises and the institutes of bankruptcy law, including those applicable to cooperative societies; the second chapter analyses the cooperative society as a social economy company and demonstrates its entrepreneurs economic reality, its structural characteristics and adds international orientations on the promotion of cooperatives; the third chapter evaluates the appropriateness of bankruptcy law related to cooperatives in Brazil and formulates propositions on the issue. The relation between theory and practice is demonstrated with judicial decisions on the matter.
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O direito concursal das sociedades cooperativas e a lei de recuperação de empresas e falência / Cooperative bankrupty system and the Brazilian bankruptcy lawEmanuelle Urbano Maffioletti 25 May 2010 (has links)
A tese parte da análise jurídica do concurso das sociedades cooperativas para abordar as disciplinas concursais de insolvência civil, recuperação de empresas e falência, bem como as normas de liquidação aplicáveis às cooperativas no direito brasileiro e comparado. O direito concursal hodierno dispõe de mecanismos recuperativos em caso de crise financeira, e liquidatórios, com normas que primam pela eficiência dos institutos do direito concursal e pela continuação da atividade produtiva, com o fim de beneficiar o credor, devedor e a coletividade. Tende-se a adotar o princípio de unidade legal, de sistema e de disciplina, com pressuposto subjetivo unificado, abrangendo todos os devedores, inclusive as sociedades cooperativas, que quando organizadas como empresas são empresárias de economia social, com natureza jurídica e estrutura que beneficiam a coletividade. O Brasil não adota o princípio da unidade, nem reconhece as sociedades cooperativas como empresas, com a exclusão das cooperativas da lei de recuperação e falências, o que fere as orientações internacionais de incentivo e de tratamento não discriminatório às sociedades cooperativas e surge como mais um obstáculo ao seu desenvolvimento no Brasil. Este estudo teórico-descritivo subdivide-se em três capítulos: o primeiro aborda a doutrina e a normativa do direito concursal com enfoque na sociedade cooperativa, analisando a evolução do direito concursal, os pressupostos subjetivos e os institutos do direito concursal brasileiro, inclusive os aplicáveis às sociedades cooperativas; o segundo aprofunda o estudo da sociedade cooperativa como empresa de economia social para demonstrar a sua realidade econômica empresarial e as suas características estruturais, além de as orientações internacionais sobre a promoção da cooperativa; e o terceiro avalia a adequação do direito concursal das cooperativas no Brasil e formula proposições sobre a matéria. A relação teoria e prática tem como base as decisões judiciais existentes sobre a matéria. / The thesis begins with the legal analysis of the bankruptcy of cooperative societies to address the legal types of bankruptcy non-commercial entities insolvency system (insolvência civil), companies recovery system and bankruptcy and the liquidation rules applicable to cooperatives under Brazilian law and comparative law. The bankruptcy law nowadays has recovery mechanisms in cases of financial crisis and liquidation. It presents rules that aim at efficiency and at the continuity of the production, in order to benefit creditors, debtors and the community. There is a tendency to adopt the legal unit principle, the system principle and the discipline principle, with a unified subjective premise that covers all debtors, including cooperative societies. When organized as companies, these societies are social economy entrepreneurs, whose juridical nature and structure benefit the community. Brazil does not adopt the legal unit principle and does not recognize cooperative societies as companies, with the exception of the cooperatives covered by the recovery and bankruptcy law. This fact constitutes a disagreement in relation to international orientations of promotion and non-discriminatory treatment to cooperative societies and arises as an obstacle to the development of these societies in the country. The theoretical-descriptive study is divided into three chapters: the first one presents the doctrine and the rules related to bankruptcy law focusing the aspects of cooperative societies and analyzing the evolution, the subjective premises and the institutes of bankruptcy law, including those applicable to cooperative societies; the second chapter analyses the cooperative society as a social economy company and demonstrates its entrepreneurs economic reality, its structural characteristics and adds international orientations on the promotion of cooperatives; the third chapter evaluates the appropriateness of bankruptcy law related to cooperatives in Brazil and formulates propositions on the issue. The relation between theory and practice is demonstrated with judicial decisions on the matter.
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My media favorites on any device : A study about the development and evaluation of a partly cloud-based and partly on-premise solution based on Microsoft PlatformDanielsson, Jennifer, Danielsson, Oliver January 2021 (has links)
Background Using Microsoft Platforms as a base for creating a software solution with a web front-end, the motives and research behind the technology was explored. This study identified functionalities that are split across existing media-related applications where neither has all to develop and evaluate a novel solution with useful features for sorting and indexing media. Aim Produce a solution for the development of an application with available technology, provide research and motives for chosen implementation strategies, and an evaluation of the solution. Method Design and creation was used as a strategy for the purpose of developing and evaluating a software solution. A literature review was used as data collection method, serving as motive and research behind the development of a software solution. An evaluation on accessibility, functionality and performance was chosen to estimate the worth of the proposed solution, and to be compared with Kodi and Squeezebox. Results The proposed solution suffered in performance and accessibility. In terms of functionality, it has the edge by being cloud-hosted,having offline support and supporting multiple media types. Kodi excelled in supporting more media types and formats, with an accessibility score close to Zavorite. Squeezebox excelled in performance. Both Squeezebox and Kodi has the edge in being able to playback media, a feature Zavorite does not offer. Conclusions Zavorite is a prototype evaluated alongside product-ready applications. The areas where Zavorite is lacking compared to Kodi or Squeezebox, such as performance is made up for due to being a PWA. For accessibility, the evaluation showed what should be improved for subsequent prototypes. For functionality, despite the prototype only showcasing two media types, there is the possibility of adding more with an additional row in a database table. Zavorite can be considered a combination of Kodi and Squeezebox, with user experience improvements as a PWA, limited to sorting and indexing media.
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Forecasting in the Unseeable: A Mixed Methods Model of Planktonic and Biofilm-Bound Legionella pneumophila in Building Water SystemsMraz, Alexis Layman January 2018 (has links)
No description available.
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Modelling and analysis of dynamic spectrum sharing in cognitive radio based wireless regional area networks :|bmodelling and performance evaluation of initialization and network association of customer premise equipments with the base station in cognitive radio based IEEE 802.22 wireless regional area networks.Afzal, Humaira January 2014 (has links)
The development of the IEEE 802.22 standard is aimed at providing broadband access in rural areas by effectively utilizing the unused TV band, provided no harmful interference is caused to the incumbent operation. This thesis presents the analytical framework to evaluate the number of active customer premise equipments (CPEs) in a wireless regional area network.
Initial ranging is the primary process in IEEE 802.22 networks for CPEs to access the network and establish their connections with the base station (BS). A comprehensive analysis of initial ranging mechanism is provided in this work and initial ranging request success probability is derived based on the number of contended CPEs and the initial contention window size. Further, the average ranging success delay is derived for the maximum backoff stages. The collision probability is highly dependent on the size of the initial contention window and the number of contended CPEs. To keep it at a specific level, it is necessary for the BS to schedule the required size of the initial contention window to facilitate the maximum number of CPEs to establish their connections with reasonable delay. Therefore, the optimized initial window size is proposed that meets the collision probability constraint for a particular number of contended CPEs.
An analytical model is also developed to estimate the ranging request collision probability depending upon the size of initial contention window and the number of contended CPEs. Moreover, this approximation provides the threshold size for contention window to start the initial ranging process in the IEEE 802.22 network. / Bahauddin Zakariya University Multan, Pakistan.
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CRM jako softwarová služba v cloudu / CRM as a Cloud software serviceDufek, Jaroslav January 2011 (has links)
This diploma thesis deals with information systems for Customer Relationship Management (CRM) and its combination with one of the main recent information technology trends -- Cloud Computing. CRM systems represent fundamental company software. Thanks to Cloud Computing ideas CRM is available now via communication networks as a service with all its relevant benefits and risks. The goal of this thesis is to evaluate CRM provided as a software service, to compare a traditional deployment of CRM as on-premise software with Software-as-a-Service (SaaS), to identify its advantages and disadvantages and finally to offer answers and evaluation of the main Cloud CRM risks. The first part describes CRM background and Cloud Computing principles. The second part compares on-premise and SaaS deployments and evaluates its benefits and risks including a detail cost analysis. The last part deals with Cloud CRM integration possibilities and practical implementation experience including a case study. This thesis offers the answers to bridge the gap between the theoretical and the practical Cloud CRM experience as the main benefit.
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Přehled nástrojů pro řízení webových projektů / Overview of project management tools for managing web based projectsHost, Daniel January 2013 (has links)
The thesis focuses on analysis and the selection of an appropriate project management tool for web based projects. The theoretical part characterizes project management, level of project management in IT environment and web based projects with their specifics. Within the web based projects, it characterizes the possibilities of development and delivery of the Web applications and the methodology used in the development -- rigorous and agile methodologies. The work focuses on the description of agile methodologies in managing software development and their usage in the management of web based projects. Procedures and ways of managing agile methodologies are reflected in the definition of requirements for functionality analyzed among the project management tools in the practical part. The practical part focuses on the description and characteristics of a sample of project management tools used in web based projects and analyzes the selection of the most appropriate one. Evaluation of project management tools is based on the level of compliance with the pre-defined functionalities and comparison of the cost of acquisition and operation for a 3 years period. The functionality of the selected project management tools is evaluated on the basis of meeting the level 8 defined areas. The cost for the project tools are evaluated in the methods of acquisition, which offers their suppliers - On-Premise, On-Demand with proprietary tools and Open Source Software tools under the GNU General Public License.
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Hybrid Cloud Migration Challenges. A case study at KingBoronin, Mikhail January 2020 (has links)
Migration to the cloud has been a popular topic in industry and academia in recent years. Despite many benefits that the cloud presents, such as high availability and scalability, most of the on-premise application architectures are not ready to fully exploit the benefits of this environment, and adapting them to this environment is a non-trivial task.Therefore, many organizations consider a gradual process of moving to the cloud with Hybrid Cloud architecture. In this paper, the author is making an effort of analyzing particular enterprise case in cloud migration topics like cloud deployment, cloud architecture and cloud management.This paper aims to identify, classify, and compare existing challenges in cloud migration, illustrate approaches to resolve these challenges and discover the best practices in cloud adoption and process of conversion teams to the cloud.
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