Dissertations / Theses: 'CPM network'

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Samoilyk, Ievgen. "Návrh projektu výrobní linky se vzdálenou kontrolou." Master's thesis, Vysoké učení technické v Brně. Fakulta podnikatelská, 2016. http://www.nusl.cz/ntk/nusl-241416.

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This thesis describes project design of a production line with remote monitoring. Specifies the basic concepts and methods of project management. Thesis analyses the current state of society and the environment. Thesis specializes in the design project.

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Farníková, Jana. "Studie průběhu zakázky podnikem." Master's thesis, Vysoké učení technické v Brně. Fakulta podnikatelská, 2013. http://www.nusl.cz/ntk/nusl-224179.

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This thesis focusses on how a specific order is processed in a specific company. The analysis is more specifically focussed on heat meters, which make up a substantial part of the company sales. It contains suggestions on how the company could process these orders using a program called Microsoft Project, which could benefit the company in many respects.

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Turner, Lyle Robert. "Production structure models and applications within a Statistical Activity Cost Theory (SACT) Framework." Thesis, Queensland University of Technology, 2007. https://eprints.qut.edu.au/16310/1/Lyle_Turner_Thesis.pdf.

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Statistical Activity Cost Theory (SACT) is an axiomatic and statistical theory of basic accounting measurement practice. The aim of the SACT analysis, among others, is to determine the statistical nature of both the physical production system of an accounting entity and its related costs, which can then be examined and applied to various decision-making problems. A central proposition of SACT is that the physical system of the entity, and the costs related to this system, are separate structures which can be modelled as such. To date, however, mini- mal progress has been made in describing production process structures within the SACT framework, and nor have there been any advances made in applying common statistical techniques to such an analysis. This thesis, therefore, moves to extend the basic theory that has already been developed, presenting a novel method for representing and examining the physical processes that make up an entity's production system. It also examines the costing of these physical models, such that transactional data can be examined and related back to the underlying production processes. The thesis concludes by giving an example of such an application in a case study. The analysis developed in this thesis has been applied in a larger project which aims to produce generic modelling and decision tools, based upon SACT, to support return and risk management.

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Turner, Lyle Robert. "Production structure models and applications within a Statistical Activity Cost Theory (SACT) Framework." Queensland University of Technology, 2007. http://eprints.qut.edu.au/16310/.

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Statistical Activity Cost Theory (SACT) is an axiomatic and statistical theory of basic accounting measurement practice. The aim of the SACT analysis, among others, is to determine the statistical nature of both the physical production system of an accounting entity and its related costs, which can then be examined and applied to various decision-making problems. A central proposition of SACT is that the physical system of the entity, and the costs related to this system, are separate structures which can be modelled as such. To date, however, mini- mal progress has been made in describing production process structures within the SACT framework, and nor have there been any advances made in applying common statistical techniques to such an analysis. This thesis, therefore, moves to extend the basic theory that has already been developed, presenting a novel method for representing and examining the physical processes that make up an entity's production system. It also examines the costing of these physical models, such that transactional data can be examined and related back to the underlying production processes. The thesis concludes by giving an example of such an application in a case study. The analysis developed in this thesis has been applied in a larger project which aims to produce generic modelling and decision tools, based upon SACT, to support return and risk management.

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Entlová, Radka. "Návrh projektu a aplikace metodiky projektového managementu v podniku." Master's thesis, Vysoké učení technické v Brně. Fakulta podnikatelská, 2013. http://www.nusl.cz/ntk/nusl-224155.

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The master’s thesis considers a project proposal for development of application software for customer’s needs. The thesis specifies the basic concepts and methods of project management. It contains analysis of the current state of company and its environment. The thesis focuses on the project proposal.

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Horvath, A. Elisabet. "The effects of cellulosic fiber charges on polyelectrolyte adsorption and fiber-fiber interactions." Doctoral thesis, Stockholm : Department of Fibre and Polymer Technology, Royal Institute of Technology, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4158.

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Ostovari, Pouya. "Priority-Based Data Transmission in Wireless Networks using Network Coding." Diss., Temple University Libraries, 2015. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/360800.

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Computer and Information Science Ph.D. With the rapid development of mobile devices technology, they are becoming very popular and a part of our everyday lives. These devices, which are equipped with wireless radios, such as cellular and WiFi radios, affect almost every aspect of our lives. People use smartphone and tablets to access the Internet, watch videos, chat with their friends, and etc. The wireless connections that these devices provide is more convenient than the wired connections. However, there are two main challenges in wireless networks: error-prone wireless links and network resources limitation. Network coding is widely used to provide reliable data transmission and to use the network resources efficiently. Network coding is a technique in which the original packets are mixed together using algebraic operations. In this dissertation, we study the applications of network coding in making the wireless transmissions robust against transmission errors and in efficient resource management. In many types of data, the importance of different parts of the data are different. For instance, in the case of numeric data, the importance of the data decreases from the most significant to the least significant bit. Also, in multi-layer videos, the importance of the packets in different layers of the videos are not the same. We propose novel data transmission methods in wireless networks that considers the unequal importance of the different parts of the data. In order to provide robust data transmissions and use the limited resources efficiently, we use random linear network coding technique, which is a type of network coding. In the first part of this dissertation, we study the application of network coding in resource management. In order to use the the limited storage of cache nodes efficiently, we propose to use triangular network coding for content distribution. We also design a scalable video-on-demand system, which uses helper nodes and network coding to provide users with their desired video quality. In the second part, we investigate the application of network coding in providing robust wireless transmissions. We propose symbol-level network coding, in which each packet is partitioned to symbols with different importance. We also propose a method that uses network coding to make multi-layer videos robust against transmission errors. Temple University--Theses

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Holifield, Gregory. "CHARACTERIZATION OF CRITICAL NETWORK COMPONENTS OF COUPLED OSCILLATORS." Doctoral diss., University of Central Florida, 2006. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2691.

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This dissertation analyzes the fundamental limits for the determination of the network structure of loosely coupled oscillators based on observing the behavior of the network, specifically, node synchronization. The determination of the requisite characteristics and underlying behaviors necessary for the application of a theoretical mechanism for determining the underlying network topology in a network of loosely coupled natural oscillators are the desired outcome. To that end, this effort defines an analytical framework where key components of networks of coupled oscillators are isolated in order to determine the relationships between the various components. The relationship between the number of nodes in a network, the number of connections in the network, the number of connections of a given node, the distribution of the phases of the network, and the resolution of measurement of the components of the network, and system noise is investigated. Ph.D. School of Electrical Engineering and Computer Science Engineering and Computer Science Computer Engineering

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Tarigopula, Srivamsi Mohanty Saraju. "A cam-based, high-performance classifier-scheduler for a video network processor." [Denton, Tex.] : University of North Texas, 2008. http://digital.library.unt.edu/permalink/meta-dc-6045.

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PEPPAS, NIKOLAOS. "A HYBRID ROUTING PROTOCOL FOR COMMUNICATIONS AMONG NODES WITHHIGH RELATIVE SPEED IN WIRELESS MESH NETWORKS." Master's thesis, University of Central Florida, 2007. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2345.

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Wireless mesh networks (WMN) is a new promising wireless technology which uses already available hardware and software components. This thesis proposes a routing algorithm for military applications. More specifically, a specialized scenario consisting of a network of flying Unmanned Aerial Vehicles (UAVs) executing reconnaissance missions is investigated. The proposed routing algorithm is hybrid in nature and uses both reactive and proactive routing characteristics to transmit information. Through simulations run on a specially built stand alone simulator, based on Java, packet overhead, delivery ratio and latency metrics were monitored with respect to varying number of nodes, node density and mobility. The results showed that the high overhead leads to high delivery ratio while latency tends to increase as the network grows larger. All the metrics revealed sensitivity in high mobility conditions. M.S.Cp.E. School of Electrical Engineering and Computer Science Engineering and Computer Science Computer Engineering MSCpE

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Tarigopula, Srivamsi. "A CAM-Based, High-Performance Classifier-Scheduler for a Video Network Processor." Thesis, University of North Texas, 2008. https://digital.library.unt.edu/ark:/67531/metadc6045/.

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Classification and scheduling are key functionalities of a network processor. Network processors are equipped with application specific integrated circuits (ASIC), so that as IP (Internet Protocol) packets arrive, they can be processed directly without using the central processing unit. A new network processor is proposed called the video network processor (VNP) for real time broadcasting of video streams for IP television (IPTV). This thesis explores the challenge in designing a combined classification and scheduling module for a VNP. I propose and design the classifier-scheduler module which will classify and schedule data for VNP. The proposed module discriminates between IP packets and video packets. The video packets are further processed for digital rights management (DRM). IP packets which carry regular traffic will traverse without any modification. Basic architecture of VNP and architecture of classifier-scheduler module based on content addressable memory (CAM) and random access memory (RAM) has been proposed. The module has been designed and simulated in Xilinx 9.1i; is built in ISE simulator with a throughput of 1.79 Mbps and a maximum working frequency of 111.89 MHz at a power dissipation of 33.6mW. The code has been translated and mapped for Spartan and Virtex family of devices.

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Siqueira, Marcos Antonio de 1978. "Redes ópticas de transporte definidas por software com suporte à virtualização e operação autônoma com base em políticas." [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/260678.

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Orientador: Christian Rodolfo Esteve Rothenberg Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação Made available in DSpace on 2018-08-27T08:39:20Z (GMT). No. of bitstreams: 1 Siqueira_MarcosAntoniode_D.pdf: 7263131 bytes, checksum: fad0f39a012c338503de664fbec8fe8c (MD5) Previous issue date: 2015 Resumo: Esta tese apresenta uma proposta de arquitetura para controle de redes ópticas de transporte que utiliza o paradigma de redes definidas por software, com suporte a operação autonômica com base em políticas. A arquitetura é constituída pelos seguintes pilares: (i) modelagem dos elementos de rede, incluindo suas interconexões, restrições, capacidades, entre outros, utilizando a linguagem YANG; (ii) composição dos modelos dos elementos de rede e suas relações em um modelo que representa a rede, suportando transformações para representação da rede como grafos de propriedades; e (iii) um modelo de políticas baseado em objetos associados ao grafo de propriedades da rede que viabiliza a operação autonômica do controlador. A proposta foi validada através de provas de conceito realizadas por simulações, protótipos e experimentos, incluindo casos de uso de segmentação e virtualização da rede óptica de transporte, aplicações SDN para ajuste de parâmetros operacionais da rede com base em políticas, bem como a operação autônoma do controlador SDN com auxílio de ferramentas de simulação com rotinas de planejamento automatizado Abstract: This thesis proposes an architecture for optical transport networks control, using the software defined networking paradigm, with support for policy-based autonomic operation. The architecture is composed of three pillars: (i) modeling of network elements, its interconnections, constraints and capabilities using the YANG language; (ii) composition of the network element models and its interconnections forming a network model, supporting transformations for representing the network as property graphs; and (iii) a policy model based on objects associated to the network graph designed for allowing autonomic operation of the network controller. The proposal has been validated through a set of proofs of concept performed via simulations, prototypes and experiments, including use cases for optical transport network slicing and virtualization, SDN applications for policy-based operational parameters adjustment, and autonomic operation of the SDN controller assisted by simulation tools with routines for automated planning Doutorado Engenharia de Computação Doutor em Engenharia Elétrica

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Carman, Karlie. "Effects of mechanical habitat disturbance on the diversity and network structure of plant-bee interaction networks in Central Florida." Master's thesis, University of Central Florida, 2014. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/6252.

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Ecological interactions within a community shape the structure of ecosystems and influence ecosystem function. Plant-pollinator interactions exist as mutualistic exchange networks that may collapse as habitat loss occurs, thereby threatening the overall health of an ecosystem. Understanding the impacts of human-mediated habitat disturbance on ecological interactions is therefore crucial for conservation efforts. Archbold Biological Station (ABS) in Venus, Florida contains over 2000 hectares of protected Florida scrub habitat nested within a human-dominated environment that is threatened by anthropogenic habitat disturbance. In past studies, over 113 bee species and 157 associated host plants, many endemic to the Lake Wales Ridge, have been found on ABS property, providing an understanding of this system's plant-bee network. Using those data as a baseline, this study investigated the effects of varying levels of mechanical habitat disturbance intensity on the diversity and network structure of plant-bee interaction networks. Flowering plant abundance, richness, diversity, and composition as well as bee abundance and composition were significantly different across mechanical habitat disturbance levels. Interactions between bees and flowering plants also differed with varying disturbance intensity. From these results, it is clear that plants, bees and interactions between them are impacted by mechanical habitat disturbance in this system. This project informs management efforts not only for natural systems with the threat of alteration, but also for agricultural systems, many of which heavily rely on flower visitation by bee pollinators. This research also contributes to the growing field of interaction ecology by increasing understanding of habitat alteration effects on a valuable ecological interaction and ultimately ecosystem function. M.S. Masters Biology Sciences Biology

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Tariq, Javid, and Sohail Sajid. "Robust Home Care Access Network." Thesis, Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-2616.

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Critical networks e.g. telecare services, telemonitoring, are implemented to provide the information security and reliability that the end user desires, especially during an emergency. Unlike business carrier systems that are planned for the general public’s use, critical communication systems are designed particularly for public protection and other serious communication situations. Availability and reliability of such networks is highly desirable. The following thesis works to compare and analyze a variety of communication access technologies to find out the best primary means of data transportation for health critical services and model reliable communication link by using redundancy. This study also provides an efficient failover mechanism to implement redundant links. This strategy is intended to provide the reliable communication and to protect the established communication link.

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Wegner, Douglas. "Governança, gestão e capital social em redes horizontais de empresas : uma análise de suas relações com o desempenho das empresas participantes." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2011. http://hdl.handle.net/10183/27955.

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O presente estudo foi motivado por lacunas teóricas sobre a governança e gestão de redes horizontais de empresas e suas relações com o capital social dos empresários e o desempenho das empresas participantes. Argumenta-se que, apesar do interesse acadêmico na cooperação interorganizacional, os estudos enfatizam excessivamente os motivos e benefícios das estratégias cooperativas, mas pouco os aspectos internos de organização das redes horizontais. Além disso, estima-se que no Brasil tenham sido constituídas até o presente aproximadamente 1.000 redes horizontais, formadas principalmente por micro e pequenas empresas que mantêm sua individualidade legal, mas usufruem dos benefícios que o trabalho em rede proporciona. Através de uma pesquisa com 218 empresas associadas a 34 redes horizontais no Brasil, analisou-se como a governança da rede, as práticas de gestão da rede e o capital social dos empresários estão relacionados ao desempenho empresarial. Os resultados mostram que a governança se modifica de acordo com as características da rede em termos de tempo de existência, número de associados e abrangência geográfica. Além disso, verificou-se a relação negativa da centralização das decisões nas redes tanto para o desempenho das empresas associadas quanto para o capital social dos empresários. Esse resultado aponta para um dilema que as redes brasileiras devem enfrentar à medida que crescem: desenvolver sistemas de governança que sejam suficientemente ágeis e eficientes em mercados altamente competitivos e que, ao mesmo tempo, garantam a participação dos empresários e o alinhamento das decisões com os interesses dos associados. As análises também confirmaram o papel do capital social do empresário como fonte de informações e recursos positivamente relacionados aos resultados da sua empresa, assim como o papel das práticas de gestão da rede para potencializar esse desempenho. Entre as contribuições teóricas do trabalho está a adoção de uma nova perspectiva do conceito de governança em redes horizontais de empresas, entendido aqui como as ‘regras do jogo’ da cooperação. O estudo também confirma a importância do número e diversidade dos contatos dos empresários dentro da rede, a qualidade dos relacionamentos e a semelhança cognitiva para o desempenho empresarial. Verificou-se ainda que o nível de acesso a informações atua como variável mediadora da influência do capital social sobre o desempenho empresarial. This study was motivated by the theoretical gaps that exist in the network governance, network management and social capital of entrepreneurs and their relations with the performance of network firms. It is argued that despite the academic interest in interorganizational cooperation, studies overemphasize the reasons and benefits of cooperative strategies and give little attention to the internal aspects of the network organization. Besides that, it is currently estimated that in Brazil approximately 1,000 horizontal networks have been created. Such networks consist mainly of micro and small firms, which maintain their individuality, but enjoy the benefits that networking brings. Through a survey of 218 firms associated to 34 horizontal business networks in Brazil, the study analyzed how the governance and management practices adopted by the network and social capital of entrepreneurs are related to business performance. The study highlights that the network governance changes according to the characteristics of the network on duration, number of members and geographic coverage. In addition, there was a negative influence of centralized decision-making in networks, both for the performance of member firms and for the social capital of entrepreneurs. This result points to a dilemma that the Brazilian networks must face as they grow: develop governance systems that ensure the participation and alignment of decisions with the interests of members, while being sufficiently agile and efficient in highly competitive markets. The analysis also confirmed the role of the entrepreneurs’ social capital as a source of information and resources positively related to the performance of the firm, as well as the role of network management practices to enhance this performance. One of the theoretical contributions of the study is to adopt a new perspective on the concept of governance in horizontal business networks, understood here as the 'rules of the game' of the cooperation. The study also confirms the importance of the number and diversity of contacts, the quality of relationships and cognitive similarity that entrepreneurs have with their contacts for business performance. It was also found that the level of access to information acts as a mediating variable of the influence of social capital on corporate performance.

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Nawathe, Piyush. "Neural Network Trees and Simulation Databases: New Approaches for Signalized Intersection Crash Classification and Prediction." Master's thesis, University of Central Florida, 2005. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4067.

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Intersection related crashes form a significant proportion of the crashes occurring on roadways. Many organizations such as the Federal Highway Administration (FHWA) and American Association of State Highway and Transportation Officials (AASHTO) are considering intersection safety improvement as one of their top priority areas. This study contributes to the area of safety of signalized intersections by identifying the traffic and geometric characteristics that affect the different types of crashes. The first phase of this thesis was to classify the crashes occurring at signalized intersections into rear-end, angle, turn and sideswipe crash types based on the traffic and geometric properties of the intersections and the conditions at the time of the crashes. This was achieved by using an innovative approach developed in this thesis "Neural Network Trees". The first neural network model built in the Neural Network tree classified the crashes either into rear end and sideswipe or into angle and turn crashes. The next models further classified the crashes into their individual types. Two different neural network methods (MLP and PNN) were used in classification, and the neural network with a better performance was selected for each model. For these models, the significant variables were identified using the forward sequential selection method. Then a large simulation database was built that contained all possible combinations of intersections subjected to various crash conditions. The collision type of crashes was predicted for this simulation database and the output obtained was plotted along with the input variables to obtain a relationship between the input and output variables. For example, the analysis showed that the number of rear end and sideswipe crashes increase relative to the angle and turn crashes when there is an increase in the major and minor roadways' AADT and speed limits, surface conditions, total left turning lanes, channelized right turning lanes for the major roadway and the protected left turning lanes for the minor roadway, but decrease when the light conditions are dark. The next phase in this study was to predict the frequency of different types of crashes at signalized intersections by using the geometric and traffic characteristics of the intersections. A high accuracy in predicting the crash frequencies was obtained by using another innovative method where the intersections were first classified into two different types named the "safe" and "unsafe" intersections based on the total number of lanes at the intersections and then the frequency of crashes was predicted for each type of intersections separately. This method consisted of identifying the best neural network for each step of the analysis, selecting significant variables, using a different simulation database that contained all possible combinations of intersections and then plotting each input variable with the average output to obtain the pattern in which the frequency of crashes will vary based on the changes in the geometric and traffic characteristics of the intersections. The patterns indicated that an increase in the number of lanes of the major roadway, lanes of the minor roadway and the AADT on the major roadway leads to an increased crashes of all types, whereas an increase in protected left turning lanes on the major road increases the rear end and sideswipe crashes but decreases the angle, turning and overall crash frequencies. The analyses performed in this thesis were possible due to a diligent data collection effort. Traffic and geometric characteristics were obtained from multiple sources for 1562 signalized intersections in Brevard, Hillsborough, Miami-Dade, Seminole and Orange counties and the city of Orlando in Florida. The crash database for these intersections contained 27,044 crashes. This research sheds a light on the characteristics of different types of crashes. The method used in classifying crashes into their respective collision types provides a deeper insight on the characteristics of each type of crash and can be helpful in mitigating a particular type of crash at an intersection. The second analysis carried out has a three fold advantage. First, it identifies if an intersection can be considered safe for different crash types. Second, it accurately predicts the frequencies of total, rear end, angle, sideswipe and turn crashes. Lastly, it identifies the traffic and geometric characteristics of signalized intersections that affect each of these crash types. Thus the models developed in this thesis can be used to identify the specific problems at an intersection, and identify the factors that should be changed to improve its safety M.S.C.E. Department of Civil and Environmental Engineering Engineering and Computer Science Civil Engineering

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Sandqvist, Mattias, and Robert Johansson. "Implementation av Network Admission Control." Thesis, Jönköping University, JTH, Computer and Electrical Engineering, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-901.

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This examination work is about implementation of Cisco Systems Network Admission Control (NAC) within a leading IT-company in region of Jönköping. NAC is a technique that is used for securing the internal network from the inside. NAC can verify that the client who connects to the network has the latest antivirus updates and latest operative system hotfixes. Clients who don’t meet the criteria can be placed in quarantine VLAN where they only have access to the update servers. There are also functions that handle VLAN assignment for users.The assignment where to produce a solution for an implementation of NAC in the company’s computer network. The questions that where asked are the following, if and how could NAC be implemented in the company’s computer network.An analysis where made of the company’s computer network, to see if the computer network meet the requirements for implementing NAC. The result of this analysis showed that there where a loss of functions needed for a working NAC solution. The computer network where rebuild from scratch to meet the new demands for NAC. After completion of the new computer network the NAC solution were taking shape. This was made in consultation with the company to get a clear picture of the needs. The result of the discussion lead to a so called “Out-of-band virtual gateway” solution. The solution builds on that the client is placed in an authentication VLAN when connecting to the computer network, after that an authentication process begins. During this process the client is checked to verify that the criteria’s are fulfilled, if so the client is moved to his access VLAN.These solutions increase the internal security in the computer network and reduce the risks for virus spreading within the network.

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Binette, Aja Jacqueline. "Positions of Authority And Influence In Environmental Nongovernmental Organizations' Networks: An Examination of Network Structure and Participation at UN Climate Change Summits." Diss., Temple University Libraries, 2018. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/513885.

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Political Science Ph.D. Which environmental non-governmental organizations (ENGOs) are positioned to be the most influential in climate negotiations? The structure of the environmental movement has undergone significant change over the development of the United Nations Framework Convention on Climate Change (UNFCCC). Since its inception there has been significant engagement by ENGOs with the yearly Conference of the Parties (COPs). In this tripartite project, I use an original dataset of relationship ties between ENGOs to construct a series of networks using social network analysis. Specifically, I examine network structures prior to three watershed moments in the history of the UNFCCC, the Kyoto, Copenhagen, and Paris COPs. Based on social network theory, an ENGO’s structural position can be viewed as a reflection of an ENGO’s perceived power, authority, and influence. I also study ENGO participation at COPs at these three distinct time points. In part one of this project, I describe how the structure of the environmental movement has changed over time in conjunction with the perceived success and failures of the UNFCCC process, leading to a bifurcated environmental movement. Additionally, I find that the ENGOs occupying central positions may have greater influence than other less central ENGOs, because they are more likely to serve on state delegations at the UNFCCC. In part two, I examine the role of alliance-based organizations in the larger environmental movement. Specifically, I describe how the ENGO network structure between alliance, policy and science-based organizations has changed over the history of the UNFCCC. The results suggest that alliance-based organizations occupy pivotal positions within the network, showing the potential for alliance-based organizations to help facilitate the representation of diverse viewpoints at international negotiations. In part three, I examine the relationships between ENGOs and human-centric organizations at the three distinct time points and find that despite an increased presence of ENGOs connected to human-centric organizations at the yearly COPs over time, there is still very little interconnectedness between these two movements. I also examine regions with the most ENGO/human-centric organizational connections and find Euro-centric dominance. In general, this is discussed as a missed opportunity. These findings have far reaching implications for the prospects of the UNFCCC developing, and states adopting, effective climate change policy that has the support of the environmental movement. Temple University--Theses

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Machado, Tatiane Martins. "Analisador de redes WirelessHART com capacidade de detecção de coexistência." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2014. http://hdl.handle.net/10183/97234.

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O uso de redes sem fio no ambiente industrial está crescendo cada vez mais devido às vantagens que estas redes apresentam comparadas aos sistemas cabeados. No entanto, é necessário que as redes sem fio apresentem a mesma robustez que as redes cabeadas. Para isso, é necessário garantir o enlace de rádio frequência entre os dispositivos e também é preciso que a rede atenda aos requisitos de comunicação em tempo real. O protocolo WirelessHART foi criado em 2007, sendo o primeiro padrão aberto de comunicação sem fio especialmente desenvolvido para ambientes industriais. Esse protocolo vem ganhando cada vez mais aplicabilidade na indústria devido à sua alta confiabilidade e robustez. Por se tratar de um protocolo recente, ainda existem muitas pesquisas em andamento, sendo uma das áreas relacionada a ferramentas para análise e monitoramento da rede. Tais ferramentas têm como objetivo principal capturar as mensagens que trafegam na rede, ou seja, atuam como um sniffer. No entanto, o protocolo WirelessHART apresenta algumas peculiaridades quando comparado a outras redes sem fio, como por exemplo, o uso de 15 canais diferentes. Devido a isso, muitos sniffers já propostos para redes sem fio não podem ser utilizados, pois capturam dados em apenas uma frequência. Outra questão está relacionada ao monitoramento de redes já instaladas, onde os dispositivos podem se encontrar em locais de difícil acesso. Dessa forma, é necessário que a ferramenta tenha mobilidade, ou seja, não necessite estar conectada a um computador, por exemplo. Então, uma vez que ainda não existe uma ferramenta de monitoramento ideal para redes WirelessHART, este trabalho propõe um nova ferramenta, que apresenta vantagens, tais como: captura de dados nos 15 canais utilizando apenas um receptor de rádio, armazenamento local dos dados capturados utilizando um cartão de memória e medição da energia nos canais, para obter informações a respeito de interferências na rede. Além disso, uma aplicação offline de análise dos dados apresenta estatísticas e análises a respeito dos dados capturados. Este trabalho apresenta alguns conceitos teóricos importantes a respeito do protocolo e os detalhes da implementação da ferramenta. Os resultados obtidos mostram que a ferramenta está atuando corretamente como um sniffer e está realizando a detecção de interferências na rede. Um estudo de caso mostra o comportamento da rede WirelessHART coexistindo com o padrão IEEE 802.11. The use of wireless networks in industrial environment is growing due to the advantages of these networks compared to wired systems. However, the wireless networks must have the same robustness that wired networks. It is necessary to ensure the link between devices and it is also necessary that the network meets the requirements of real-time communication. The WirelessHART protocol was created in 2007, and it is the first open wireless communication standard specifically designed for industrial environments. This protocol has been gaining increasing applicability in industry due to its high reliability and robustness. Because it is a recent protocol, there are still many ongoing researches. One of them is related to tools for analyzing and monitoring the network. Such tools have the main objective to capture the messages that travel on the network, acting as a sniffer. However, the WirelessHART protocol has some peculiarities as compared to other wireless networks, such as the use of 15 different channels. Because of this, many sniffers already proposed for wireless networks can not be applied, because they capture data on only one frequency. Another issue is related to the monitoring networks already installed, where devices can be found in places of difficult access. Thus, it is necessary that the tool has mobility, i.e., does not need to be connected to a computer, for example. So, since there is still no ideal monitoring tool for WirelessHART networks, this paper proposes a new tool, which has advantages such as: data capture in 15 channels using only one radio receiver, local storage of captured data using a memory card and measuring the energy in the channels for getting information about interference in the network. In addition, an offline application presents statistics and analysis about the captured data. This paper presents some important theoretical concepts about the protocol and implementation details of the tool. The results show that the tool is working properly as a sniffer and it’s performing the interference detection in the network . A case study shows the behavior of the WirelessHART network coexisting with IEEE 802.11 standard.

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LUO, SONG. "CREATING MODELS OF INTERNET BACKGROUND TRAFFIC SUITABLE FOR USE IN EVALUATING NETWORK INTRUSION DETECTION SYSTEMS." Doctoral diss., University of Central Florida, 2005. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2790.

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This dissertation addresses Internet background traffic generation and network intrusion detection. It is organized in two parts. Part one introduces a method to model realistic Internet background traffic and demonstrates how the models are used both in a simulation environment and in a lab environment. Part two introduces two different NID (Network Intrusion Detection) techniques and evaluates them using the modeled background traffic. To demonstrate the approach we modeled five major application layer protocols: HTTP, FTP, SSH, SMTP and POP3. The model of each protocol includes an empirical probability distribution plus estimates of application-specific parameters. Due to the complexity of the traffic, hybrid distributions (called mixture distributions) were sometimes required. The traffic models are demonstrated in two environments: NS-2 (a simulator) and HONEST (a lab environment). The simulation results are compared against the original captured data sets. Users of HONEST have the option of adding network attacks to the background. The dissertation also introduces two new template-based techniques for network intrusion detection. One is based on a template of autocorrelations of the investigated traffic, while the other uses a template of correlation integrals. Detection experiments have been performed on real traffic and attacks; the results show that the two techniques can achieve high detection probability and low false alarm in certain instances. Ph.D. Engineering and Computer Science Computer Science

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Shen, Haohong. "CIM and XML in network management." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0012/MQ53224.pdf.

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Zheng, Huanyang. "SOCIAL NETWORK ARCHITECTURES AND APPLICATIONS." Diss., Temple University Libraries, 2017. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/470889.

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Computer and Information Science Ph.D. Rather than being randomly wired together, the components of complex network systems are recently reported to represent a scale-free architecture, in which the node degree distribution follows power-law. While social networks are scale-free, it is natural to utilize their structural properties in some social network applications. As a result, this dissertation explores social network architectures, and in turn, leverages these architectures to facilitate some influence and information propagation applications. Social network architectures are analyzed in two different aspects. The first aspect focuses on the node degree snowballing effects (i.e., degree growth effects) in social networks, which is based on an age-sensitive preferential attachment model. The impact of the initial links is explored, in terms of accelerating the node degree snowballing effects. The second aspect focuses on Nested Scale-Free Architectures (NSFAs) for social networks. The scale-free architecture is a classic concept, which means that the node degree distribution follows the power-law distribution. `Nested' indicates that the scale-free architecture is preserved when low-degree nodes and their associated connections are iteratively removed. NSFA has a bounded hierarchy. Based on the social network structure, this dissertation explores two influence propagation applications for the Social Influence Maximization Problem (SIMP). The first application is a friend recommendation strategy with the perspective of social influence maximization. For the system provider, the objective is to recommend a fixed number of new friends to a given user, such that the given user can maximize his/her social influence through making new friends. This problem is proved to be NP-hard by reduction from the SIMP. A greedy friend recommendation algorithm with an approximation ratio of $1-e^{-1}$ is proposed. The second application studies the SIMP with the crowd influence, which is NP-hard, monotone, non-submodular, and inapproximable in general graphs. However, since user connections in Online Social Networks (OSNs) are not random, approximations can be obtained by leveraging the structural properties of OSNs. The modularity, denoted by $\Delta$, is proposed to measure to what degree this problem violates the submodularity. Two approximation algorithms are proposed with ratios of $\frac{1}{\Delta+2}$ and $1-e^{-1/(\Delta+1)}$, respectively. Beside the influence propagation applications, this dissertation further explores three different information propagation applications. The first application is a social network quarantine strategy, which can eliminate epidemic outbreaks with minimal isolation costs. This problem is NP-hard. An approximation algorithm with a ratio of 2 is proposed through utilizing the problem properties of feasibility and minimality. The second application is a rating prediction scheme, called DynFluid, based on the fluid dynamics. DynFluid analogizes the rating reference among the users in OSNs to the fluid flow among containers. The third application is an information cascade prediction framework: given the social current cascade and social topology, the number of propagated users at a future time slot is predicted. To reduce prediction time complexities, the spatiotemporal cascade information (a larger size of data) is decomposed to user characteristics (a smaller size of data) for subsequent predictions. All these three applications are based on the social network structure. Temple University--Theses

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Pick, Dorothy. "A RELATIONAL DIFFUSION NETWORK STUDY OF SYNCHRONOUS AND ASYNCHRONOUS INTERNET-BASED FACULTY'S PERSONAL NETWORK EXPOSURE MODELS R." Doctoral diss., University of Central Florida, 2006. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2409.

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For many faculty, teaching online represents a new instructional delivery method, requiring the development of new teaching skills. This exploratory investigation builds upon Rogers' (2003) Diffusion of Innovations theory and communication channels to describe the influence of faculty discussions on their perceptions and decisions about teaching and learning. A sequential explanatory mixed-methods research design, using both sociometric and phenomenological methodologies, guided the exploration of faculty personal network exposure models and social learning opportunities. The study utilized online survey and open-ended interview instruments for the investigation. Faculty from several colleges at the University of Central Florida voluntarily completed the survey instrument identifying with whom, how, and why they discuss teaching online, including the influence of these discussions. In-depth interviews offered internal descriptions of their personal networks. Survey results established baseline data for demographic and future comparisons and identified concerns, issues, and trends unique to synchronous and asynchronous Internet-based faculty development and support needs. Phenomenological data produced the emergent categories and themes used to investigate and explain faculty's communication channel usage and social learning experiences. Similarities between diffusion and knowledge research findings and participants reflected more conformity than anticipated. Differences in communication channel and learning style preferences and usage and faculty's 24/7 work life needs, present challenges to administrators and educators responsible for providing development and support systems. Ed.D. Department of Educational Studies Education Curriculum and Instruction

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Zhou, Mian. "Network Intrusion Detection: Monitoring, Simulation and Visualization." Doctoral diss., University of Central Florida, 2005. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4063.

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This dissertation presents our work on network intrusion detection and intrusion sim- ulation. The work in intrusion detection consists of two different network anomaly-based approaches. The work in intrusion simulation introduces a model using explicit traffic gen- eration for the packet level traffic simulation. The process of anomaly detection is to first build profiles for the normal network activity and then mark any events or activities that deviate from the normal profiles as suspicious. Based on the different schemes of creating the normal activity profiles, we introduce two approaches for intrusion detection. The first one is a frequency-based approach which creates a normal frequency profile based on the periodical patterns existed in the time-series formed by the traffic. It aims at those attacks that are conducted by running pre-written scripts, which automate the process of attempting connections to various ports or sending packets with fabricated payloads, etc. The second approach builds the normal profile based on variations of connection-based behavior of each single computer. The deviations resulted from each individual computer are carried out by a weight assignment scheme and further used to build a weighted link graph representing the overall traffic abnormalities. The functionality of this system is of a distributed personal IDS system that also provides a centralized traffic analysis by graphical visualization. It provides a finer control over the internal network by focusing on connection-based behavior of each single computer. For network intrusion simulation, we explore an alternative method for network traffic simulation using explicit traffic generation. In particular, we build a model to replay the standard DARPA traffic data or the traffic data captured from a real environment. The replayed traffic data is mixed with the attacks, such as DOS and Probe attack, which can create apparent abnormal traffic flow patterns. With the explicit traffic generation, every packet that has ever been sent by the victim and attacker is formed in the simulation model and travels around strictly following the criteria of time and path that extracted from the real scenario. Thus, the model provides a promising aid in the study of intrusion detection techniques. Ph.D. School of Computer Science Engineering and Computer Science Computer Science

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Johnson, Cynthia Lynn. "Counterpropagation neural network detection of visual primitives." Master's thesis, University of Central Florida, 1990. http://digital.library.ucf.edu/cdm/ref/collection/RTD/id/12639.

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University of Central Florida College of Engineering Thesis Psychological testing has shown that there is an early preattentive stage in the human visual system. At this level, simple features and properties of objects known as visual primitives are deteched spatially in parallel by groupings of cells in the visual cortex known as feature maps. In order to study this preattentive stage in a machine vision system, the biologically inspired, highly parallel architecture of the artificial neural network shows great promise. This paper describes how the unique architecture of the counterpropagation neural network was used to simulate the feature maps which detect visual primitives in the human visual system. The results of the research showed that artificial neural networks are able to reproduce the function of the feature maps with accuracy. The counterpropagation network was able to reproduce the feature maps as theorized, however, future research might investigate the abilities of other neural network algorithms in this area. Development of a method for combining the results of feature maps in a simulation of full scale early vision is also a topic for future research that would benefit from the results reported here. M.S.; Computer Engineering Engineering; Computer Engineering 63 p. iv, 63 leaves, bound : ill. ; 28 cm.

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Gellman, Michael. "Packet loss in the cognitive packet network." Honors in the Major Thesis, University of Central Florida, 2001. http://digital.library.ucf.edu/cdm/ref/collection/ETH/id/274.

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This item is only available in print in the UCF Libraries. If this is your Honors Thesis, you can help us make it available online for use by researchers around the world by following the instructions on the distribution consent form at http://library.ucf.edu/Systems/DigitalInitiatives/DigitalCollections/InternetDistributionConsentAgreementForm.pdf You may also contact the project coordinator, Kerri Bottorff, at kerri.bottorff@ucf.edu for more information. Bachelors Engineering Computer Science

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Zulu, Docas Dudu. "Packet aggregation for voice over internet protocol on wireless mesh networks." Thesis, University of the Western Cape, 2012. http://hdl.handle.net/11394/4403.

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>Magister Scientiae - MSc This thesis validates that packet aggregation is a viable technique to increase call capacity for Voice over Internet Protocol over wireless mesh networks. Wireless mesh networks are attractive ways to provide voice services to rural communities. Due to the ad-hoc routing nature of mesh networks, packet loss and delay can reduce voice quality. Even on non-mesh networks, voice quality is reduced by high overhead, associated with the transmission of multiple small packets. Packet aggregation techniques are proven to increase VoIP performance and thus can be deployed in wireless mesh networks. Kernel level packet aggregation was initially implemented and tested on a small mesh network of PCs running Linux, and standard baseline vs. aggregation tests were conducted with a realistic voice traffic profile in hop-to-hop mode. Modifications of the kernel were then transferred to either end of a nine node 'mesh potato' network and those tests were conducted with only the end nodes modified to perform aggregation duties. Packet aggregation increased call capacity expectedly, while quality of service was maintained in both instances, and hop-to-hop aggregation outperformed the end-to-end configuration 4:1. However, implementing hop-to-hop in a scalable fashion is prohibitive, due to the extensive kernel level debugging that must be done to achieve the call capacity increase. Therefore, end-to-end call capacity increase is an acceptable compromise for eventual scalable deployment of voice over wireless mesh networks.

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Napoli, Alessandro. "DISSOCIATED NEURONAL NETWORKS AND MICRO ELECTRODE ARRAYS FOR INVESTIGATING BRAIN FUNCTIONAL EVOLUTION AND PLASTICITY." Diss., Temple University Libraries, 2014. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/269449.

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Electrical Engineering Ph.D. For almost a century, the electrical properties of the brain and the nervous system have been investigated to gain a better understanding of their mechanisms and to find cures for pathological conditions. Despite the fact that today's advancements in surgical techniques, research, and medical imaging have improved our ability to treat brain disorders, our knowledge of the brain and its functions is still limited. Culturing dissociated cortical neurons on Micro-Electrode Array dishes is a powerful experimental tool for investigating functional and structural characteristics of in-vitro neuronal networks, such as the cellular basis of brain learning, memory and synaptic developmental plasticity. This dissertation focuses on combining MEAs with novel electrophysiology experimental paradigms and statistical data analysis to investigate the mechanisms that regulate brain development at the level of synaptic formation and growth cones. The goal is to use a mathematical approach and specifically designed experiments to investigate whether dissociated neuronal networks can dependably display long and short-term plasticity, which are thought to be the building blocks of memory formation in the brain. Quantifying the functional evolution of dissociated neuronal networks during in- vitro development, using a statistical analysis tool was the first aim of this work. The results of the False Discovery Rate analysis show an evolution in network activity with changes in both the number of statistically significant stimulus/recording pairs as well as the average length of connections and the number of connections per active node. It is therefore proposed that the FDR analysis combined with two metrics, the average connection length and the number of highly connected "supernodes" is a valuable technique for describing neuronal connectivity in MEA dishes. Furthermore, the statistical analysis indicates that cultures dissociated from the same brain tissue display trends in their temporal evolution that are more similar than those obtained with respect to different batches. The second aim of this dissertation was to investigate long and short-term plasticity responsible for memory formation in dissociated neuronal networks. In order to address this issue, a set of experiments was designed and implemented in which the MEA electrode grid was divided into four quadrants, two of which were chronically stimulated, every two days for one hour with a stimulation paradigm that varied over time. Overall network and quadrant responses were then analyzed to quantify what level of plasticity took place in the network and how this was due to the stimulation interruption. The results demonstrate that here were no spatial differences in the stimulus-evoked activity within quadrants. Furthermore, the implemented stimulation protocol induced depression effects in the neuronal networks as demonstrated by the consistently lower network activity following stimulation sessions. Finally, the analysis demonstrated that the inhibitory effects of the stimulation decreased over time, thus suggesting a habituation phenomenon. These findings are sufficient to conclude that electrical stimulation is an important tool to interact with dissociated neuronal cultures, but localized stimuli are not enough to drive spatial synaptic potentiation or depression. On the contrary, the ability to modulate synaptic temporal plasticity was a feasible task to achieve by chronic network stimulation. Temple University--Theses

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Sullivan, Diane. "DYNAMIC ENTREPRENEURIAL NETWORKS: AN INVESTIGATION OF ENTREPRENEURS, NEW VENTURES AND THEIR NETWORKS." Doctoral diss., University of Central Florida, 2006. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2928.

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Entrepreneurs need resources to organize new venture offerings into marketplace-acceptable forms. Entrepreneurs use others' assistance via networks to obtain these resources. Research indicates that firms face resource dependencies, that likely change over time, where they must respond to those controlling resources. Although some work has investigated implications of new ventures' networks at one time period, little work has investigated the dynamic nature and associated outcomes of networks as they change due to different resource requirements as the venture develops. This research examines the dynamic nature of networks, due different resource requirements over time, and how these changes impact entrepreneurial outcomes via interactions with entrepreneurs' existing networks. In order to account for the dynamic nature of entrepreneurial new ventures and their networks of resource providers, a model is presented that investigates antecedents to subsequent entrepreneurial network characteristics. The model also anticipates changes eminent to the founder as a consequence of interactions with their networks due to experiences associated with the new venture development process. This work relies on network theory integrated with resource dependence theory arguments, work that examines founder attributes as associated with entrepreneurial outcomes and research that investigates the stages of new venture development. Predictions developed from the model were tested in two studies. The first study utilized the Panel Study of Entrepreneurial Dynamics, an existing panel database containing information about nascent entrepreneurs, as its data source to test predictions examining the dynamics of entrepreneurs' networks across two time frames. The second study used a cross-sectional mass mail survey design to investigate all of the model's predictions on a random sample of newly incorporated firms in the state of Florida. The results of the studies provided support for about one third of the predictions and there were a few contrasting findings across studies. Overall, the results of the studies suggest that some conceptualizations presented in the theoretical model should be reevaluated and that the applicability of some constructs when studying firms in the organizing stages of development should be reconsidered. Ph.D. Department of Management Business Administration Business Administration: Ph.D.

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McGill, Susan. "NETWORK PERFORMANCE MANAGEMENT USING APPLICATION-CENTRIC KEY PERFORMANCE INDICATORS." Doctoral diss., University of Central Florida, 2007. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4055.

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The Internet and intranets are viewed as capable of supplying "Anything, Anywhere, Anytime" and e-commerce, e-government, e-community, and military C4I are now deploying many and varied applications to serve their needs. Network management is currently centralized in operations centers. To assure customer satisfaction with the network performance they typically plan, configure and monitor the network devices to insure an excess of bandwidth, that is overprovision. If this proves uneconomical or if complex and poorly understood interactions of equipment, protocols and application traffic degrade performance creating customer dissatisfaction, another more application-centric, way of managing the network will be needed. This research investigates a new qualitative class of network performance measures derived from the current quantitative metrics known as quality of service (QOS) parameters. The proposed class of qualitative indicators focuses on utilizing current network performance measures (QOS values) to derive abstract quality of experience (QOE) indicators by application class. These measures may provide a more user or application-centric means of assessing network performance even when some individual QOS parameters approach or exceed specified levels. The mathematics of functional analysis suggests treating QOS performance values as a vector, and, by mapping the degradation of the application performance to a characteristic lp-norm curve, a qualitative QOE value (good/poor) can be calculated for each application class. A similar procedure could calculate a QOE node value (satisfactory/unsatisfactory) to represent the service level of the switch or router for the current mix of application traffic. To demonstrate the utility of this approach a discrete event simulation (DES) test-bed, in the OPNET telecommunications simulation environment, was created modeling the topology and traffic of three semi-autonomous networks connected by a backbone. Scenarios, designed to degrade performance by under-provisioning links or nodes, are run to evaluate QOE for an access network. The application classes and traffic load are held constant. Future research would include refinement of the mathematics, many additional simulations and scenarios varying other independent variables. Finally collaboration with researchers in areas as diverse as human computer interaction (HCI), software engineering, teletraffic engineering, and network management will enhance the concepts modeled. Ph.D. Other Engineering and Computer Science Modeling and Simulation PhD

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Horine, Brent. "Bootstrapping Cognitive Radio Networks." Doctoral diss., University of Central Florida, 2012. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5306.

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Cognitive radio networks promise more efficient spectrum utilization by leveraging degrees of freedom and distributing data collection. The actual realization of these promises is challenged by distributed control, and incomplete, uncertain and possibly conflicting knowledge bases. We consider two problems in bootstrapping, evolving, and managing cognitive radio networks. The first is Link Rendezvous, or how separate radio nodes initially find each other in a spectrum band with many degrees of freedom, and little shared knowledge. The second is how radio nodes can negotiate for spectrum access with incomplete information. To address the first problem, we present our Frequency Parallel Blind Link Rendezvous algorithm. This approach, designed for recent generations of digital front-ends, implicitly shares vague information about spectrum occupancy early in the process, speeding the progress towards a solution. Furthermore, it operates in the frequency domain, facilitating a parallel channel rendezvous. Finally, it operates without a control channel and can rendezvous anywhere in the operating band. We present simulations and analysis on the false alarm rate for both a feature detector and a cross-correlation detector. We compare our results to the conventional frequency hopping sequence rendezvous techniques. To address the second problem, we model the network as a multi-agent system and negotiate by exchanging proposals, augmented with arguments. These arguments include information about priority status and the existence of other nodes. We show in a variety of network topologies that this process leads to solutions not otherwise apparent to individual nodes, and achieves superior network throughput, request satisfaction, and total number of connections, compared to our baselines. The agents independently formulate proposals based upon communication desires, evaluate these proposals based upon capacity constraints, create arguments in response to proposal rejections, and re-evaluate proposals based upon received arguments. We present our negotiation rules, messages, and protocol and demonstrate how they interoperate in a simulation environment. Ph.D. Doctorate Electrical Engineering and Computer Science Engineering and Computer Science Electrical Engineering

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Injai, Hamed Nasser Sulai Ramos. "Financiamento Interbancário na Guiné-Bissau : Análise das Relações Interbancárias Com a Análise Social de Networks." Master's thesis, Instituto Superior de Economia e Gestão, 2012. http://hdl.handle.net/10400.5/4841.

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Mestrado em Finanças Esta tese de mestrado em finanças analisa o network do crédito interbancário na Guiné-Bissau, usando métodos da análise social de networks (SNA) aplicada ao mercado interbancário. Ilustra-se a tipologia de network e caracteriza-se a difusão de informação no network de crédito interbancário. Uma caracterização estática estrutural do network de crédito interbancário é identificada usando os fluxos do crédito interbancário. Em seguida analisa-se a estrutura de relações com métricas de densidade e centralidade, concluindo que a rede de crédito interbancário da Guiné-Bissau é pequena com baixo nível de centralidade e densidade. São retiradas políticas de consolidação do mercado interbancário. This master's thesis in finance analyzes the network of interbank credit lending in Guinea-Bissau, using SNA - social networks analysis applied to interbank market. The thesis illustrates that the type of credit network and characterizes the diffusion of information in the network of interbank lending. A static structural characterization of the network of interbank lending is identified using the flows of interbank lending. Then we analyze the structure of relationships with density and centrality metrics, concluding that the network of interbank lending of Guinea-Bissau is small with low centrality and density. Consolidation policies are suggests to improve centrality and density of Guinea-Bissau interbank market.

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Szumlanski, Sean. "Automatically Acquiring a Semantic Network of Related Concepts." Doctoral diss., University of Central Florida, 2013. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5712.

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We describe the automatic acquisition of a semantic network in which over 7,500 of the most frequently occurring nouns in the English language are linked to their semantically related concepts in the WordNet noun ontology. Relatedness between nouns is discovered automatically from lexical co-occurrence in Wikipedia texts using a novel adaptation of an information theoretic inspired measure. Our algorithm then capitalizes on salient sense clustering among these semantic associates to automatically disambiguate them to their corresponding WordNet noun senses (i.e., concepts). The resultant concept-to-concept associations, stemming from 7,593 target nouns, with 17,104 distinct senses among them, constitute a large-scale semantic network with 208,832 undirected edges between related concepts. Our work can thus be conceived of as augmenting the WordNet noun ontology with RelatedTo links. The network, which we refer to as the Szumlanski-Gomez Network (SGN), has been subjected to a variety of evaluative measures, including manual inspection by human judges and quantitative comparison to gold standard data for semantic relatedness measurements. We have also evaluated the network's performance in an applied setting on a word sense disambiguation (WSD) task in which the network served as a knowledge source for established graph-based spreading activation algorithms, and have shown: a) the network is competitive with WordNet when used as a stand-alone knowledge source for WSD, b) combining our network with WordNet achieves disambiguation results that exceed the performance of either resource individually, and c) our network outperforms a similar resource, WordNet++ (Ponzetto & Navigli, 2010), that has been automatically derived from annotations in the Wikipedia corpus. Finally, we present a study on human perceptions of relatedness. In our study, we elicited quantitative evaluations of semantic relatedness from human subjects using a variation of the classical methodology that Rubenstein and Goodenough (1965) employed to investigate human perceptions of semantic similarity. Judgments from individual subjects in our study exhibit high average correlation to the elicited relatedness means using leave-one-out sampling (r = 0.77, σ = 0.09, N = 73), although not as high as average human correlation in previous studies of similarity judgments, for which Resnik (1995) established an upper bound of r = 0.90 (σ = 0.07, N = 10). These results suggest that human perceptions of relatedness are less strictly constrained than evaluations of similarity, and establish a clearer expectation for what constitutes human-like performance by a computational measure of semantic relatedness. We also contrast the performance of a variety of similarity and relatedness measures on our dataset to their performance on similarity norms and introduce our own dataset as a supplementary evaluative standard for relatedness measures. Ph.D. Doctorate Computer Science Engineering and Computer Science Computer Science

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Scully, Michael N. B. "Network and system security in an information age." Honors in the Major Thesis, University of Central Florida, 2000. http://digital.library.ucf.edu/cdm/ref/collection/ETH/id/204.

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This item is only available in print in the UCF Libraries. If this is your Honors Thesis, you can help us make it available online for use by researchers around the world by following the instructions on the distribution consent form at http://library.ucf.edu/Systems/DigitalInitiatives/DigitalCollections/InternetDistributionConsentAgreementForm.pdf You may also contact the project coordinator, Kerri Bottorff, at kerri.bottorff@ucf.edu for more information. Bachelors Business Administration Management Information Systems

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Peres, Renan Piazzon. "Controle de produção em uma indústria sucroalcooleira com CCM inteligente." Universidade de Taubaté, 2010. http://www.bdtd.unitau.br/tedesimplificado/tde_busca/arquivo.php?codArquivo=310.

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Este trabalho tem como objetivo apresentar as características e conceitos da aplicação de centros de controle de motores inteligente, demonstrando as vantagens da utilização de rede industrial no controle da produção, especificamente o protocolo DeviceNet, e reunir em um documento as informações sobre a utilização e aplicações de diferentes configurações de acionamento e comando de motores instalados em um CCM. Para isso, foram realizados estudos e simulações de acionamentos elétricos protegidos por relés de sobrecarga em diferentes configurações de ligações e tecnologias utilizadas em instalações elétricas industriais, alterando os equipamentos, montagens e sinais recebidos para comando e proteção das cargas, bem como, observando os dados referentes aos custos de engenharia, instalação e materiais. Para as quatro opções analisadas foram estimados os tempos de projeto, instalação e valores estimados dos produtos e serviços necessários, fornecendo uma tabela comparativa entre as opções estudadas, além de concluir que o uso de CCM inteligente conectado ao aplicativo de supervisão IntelliCENTER se apresentou como a melhor solução, pois agrega as melhores características técnicas dos painéis elétricos, bem como a disponibilidade de monitoramento e controle da produção, com a utilização da rede DeviceNet. Além dos valores envolvidos na aquisição e startup, também foram observados os possíveis ganhos operacionais do sistema inteligente, pois permite via sistema supervisório os diagnósticos instantâneos, alarmes e desligamentos que localizam os defeitos nos acionamentos controlados. This work aims to present the intelligent motor control center characteristics and concepts by showing the advantages of the industrial network application in the manufacturing control, more specific the DeviceNet protocol and gather in one document the information about the application and how to use different configurations of drivers and motor control installed in a MCC. In order to gather this information several studies and simulation were made by changing the equipment, assembling and signals in electric drivers protected by overload relays with different technologies and kind of connections used in industrial installations and comparing the engineering, assembling, and material costs. For the four analyzed options of drivers, the project development time, installation, product costs and necessary services were estimated showing a comparative table between options. This study will prove that the intelligent MCC connected to the IntelliCENTER software is the best solution because uses the best technical solution and also have the ability to monitor and control manufacturing, using DeviceNet network. Besides the acquisition and start up values it was also observed the operational benefits of the intelligent system, showing alarms, instantaneous diagnostics, and problems in the components of the controlled starter, by means supervisory system.

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Al-Daraiseh, Ahmad. "GENETICALLY ENGINEERED ADAPTIVE RESONANCE THEORY (ART) NEURAL NETWORK ARCHITECTURES." Doctoral diss., University of Central Florida, 2006. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3171.

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Fuzzy ARTMAP (FAM) is currently considered to be one of the premier neural network architectures in solving classification problems. One of the limitations of Fuzzy ARTMAP that has been extensively reported in the literature is the category proliferation problem. That is Fuzzy ARTMAP has the tendency of increasing its network size, as it is confronted with more and more data, especially if the data is of noisy and/or overlapping nature. To remedy this problem a number of researchers have designed modifications to the training phase of Fuzzy ARTMAP that had the beneficial effect of reducing this phenomenon. In this thesis we propose a new approach to handle the category proliferation problem in Fuzzy ARTMAP by evolving trained FAM architectures. We refer to the resulting FAM architectures as GFAM. We demonstrate through extensive experimentation that an evolved FAM (GFAM) exhibits good (sometimes optimal) generalization, small size (sometimes optimal size), and requires reasonable computational effort to produce an optimal or sub-optimal network. Furthermore, comparisons of the GFAM with other approaches, proposed in the literature, which address the FAM category proliferation problem, illustrate that the GFAM has a number of advantages (i.e. produces smaller or equal size architectures, of better or as good generalization, with reduced computational complexity). Furthermore, in this dissertation we have extended the approach used with Fuzzy ARTMAP to other ART architectures, such as Ellipsoidal ARTMAP (EAM) and Gaussian ARTMAP (GAM) that also suffer from the ART category proliferation problem. Thus, we have designed and experimented with genetically engineered EAM and GAM architectures, named GEAM and GGAM. Comparisons of GEAM and GGAM with other ART architectures that were introduced in the ART literature, addressing the category proliferation problem, illustrate similar advantages observed by GFAM (i.e, GEAM and GGAM produce smaller size ART architectures, of better or improved generalization, with reduced computational complexity). Moverover, to optimally cover the input space of a problem, we proposed a genetically engineered ART architecture that combines the category structures of two different ART networks, FAM and EAM. We named this architecture UART (Universal ART). We analyzed the order of search in UART, that is the order according to which a FAM category or an EAM category is accessed in UART. This analysis allowed us to better understand UART's functionality. Experiments were also conducted to compare UART with other ART architectures, in a similar fashion as GFAM and GEAM were compared. Similar conclusions were drawn from this comparison, as in the comparison of GFAM and GEAM with other ART architectures. Finally, we analyzed the computational complexity of the genetically engineered ART architectures and we compared it with the computational complexity of other ART architectures, introduced into the literature. This analytical comparison verified our claim that the genetically engineered ART architectures produce better generalization and smaller sizes ART structures, at reduced computational complexity, compared to other ART approaches. In review, a methodology was introduced of how to combine the answers (categories) of ART architectures, using genetic algorithms. This methodology was successfully applied to FAM, EAM and FAM and EAM ART architectures, with success, resulting in ART neural networks which outperformed other ART architectures, previously introduced into the literature, and quite often produced ART architectures that attained optimal classification results, at reduced computational complexity. Ph.D. Department of Electrical and Computer Engineering Engineering and Computer Science Computer Engineering

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Engel, Jacob. "OFF-CHIP COMMUNICATIONS ARCHITECTURES FOR HIGH THROUGHPUT NETWORK PROCESSORS." Doctoral diss., University of Central Florida, 2005. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4112.

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In this work, we present off-chip communications architectures for line cards to increase the throughput of the currently used memory system. In recent years there is a significant increase in memory bandwidth demand on line cards as a result of higher line rates, an increase in deep packet inspection operations and an unstoppable expansion in lookup tables. As line-rate data and NPU processing power increase, memory access time becomes the main system bottleneck during data store/retrieve operations. The growing demand for memory bandwidth contrasts the notion of indirect interconnect methodologies. Moreover, solutions to the memory bandwidth bottleneck are limited by physical constraints such as area and NPU I/O pins. Therefore, indirect interconnects are replaced with direct, packet-based networks such as mesh, torus or k-ary n-cubes. We investigate multiple k-ary n-cube based interconnects and propose two variations of 2-ary 3-cube interconnect called the 3D-bus and 3D-mesh. All of the k-ary n-cube interconnects include multiple, highly efficient techniques to route, switch, and control packet flows in order to minimize congestion spots and packet loss. We explore the tradeoffs between implementation constraints and performance. We also developed an event-driven, interconnect simulation framework to evaluate the performance of packet-based off-chip k-ary n-cube interconnect architectures for line cards. The simulator uses the state-of-the-art software design techniques to provide the user with a flexible yet robust tool, that can emulate multiple interconnect architectures under non-uniform traffic patterns. Moreover, the simulator offers the user with full control over network parameters, performance enhancing features and simulation time frames that make the platform as identical as possible to the real line card physical and functional properties. By using our network simulator, we reveal the best processor-memory configuration, out of multiple configurations, that achieves optimal performance. Moreover, we explore how network enhancement techniques such as virtual channels and sub-channeling improve network latency and throughput. Our performance results show that k-ary n-cube topologies, and especially our modified version of 2-ary 3-cube interconnect - the 3D-mesh, significantly outperform existing line card interconnects and are able to sustain higher traffic loads. The flow control mechanism proved to extensively reduce hot-spots, load-balance areas of high traffic rate and achieve low transmission failure rate. Moreover, it can scale to adopt more memories and/or processors and as a result to increase the line card's processing power. Ph.D. Department of Electrical and Computer Engineering Engineering and Computer Science Computer Engineering

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Srinivasan, Bharath. "PROTOTYPE OF COUPLING UNIT NETWORK FOR POWER LINE COMMUNICATIONS." Master's thesis, University of Central Florida, 2006. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4261.

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Power Line Communications has made impressive strides since its introduction. Power Line Communications (PLC) or Broadband over Power Lines (BPL) is the method of transmitting broadband signals over the power lines and making it available at the power outlet in homes. It provides last mile communication and makes use of existing power lines to transmit signals, thereby eliminating the need to lay cables all over again. PLC is fast becoming a commercial reality in the United States. The Federal Communications Commission (FCC) is working toward making PLC a standard with particular emphasis on power emission issues and interference with nearby bands. Power companies, vendors and ISPs (Internet Service Providers) have tied up to bring this new technology to market. The Power line environment is inherently unpredictable due to interference, low signaling impedance and the highly linear operating environment that PLC transmitters require. The coupling unit in the PLC system acts as a filter and eliminates the harmful AC signal from interfering with the broadband signals. A coupling unit amplifier topology that provides gain equalization and wideband mitigation to the effects of low-impedance loads on PLC in the high frequency range has been explored in detail in this study. The amplifier is verified for its performance by means of circuit simulation using industry-standard software such as Agilent's Advanced Design System (ADS). The coupling unit has also been fabricated to verify the performance. An experimental setup for verifying the performance of the coupling unit using a PLC transmitter and PLC receiver has also been proposed. M.S.E.E. School of Electrical Engineering and Computer Science Engineering and Computer Science Electrical Engineering

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Terlegård, Tim. "Design of a Secure Network Management System." Thesis, Linköping University, Department of Electrical Engineering, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-1133.

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The size and complexity of local area and wide area networks are continually growing and so do the requirements of high availability. Today we rely on the technology and it should always work. Network management is therefore getting more and more important. Network management includes: monitoring and isolating faults, measuring performance, configuring the resources, making sure the network is secured and more. Since in the early 1990s the management has typically been done with SNMPv1 or CMIP and using the client/server model. SNMPv1 is insecure, CMIP is complex and the traditional centralized paradigm is no longer sufficient to handle the management requirements of large networks. As the demands for security and flexibility increases, new ways to manage networks are needed. This research tries to find out how a network management system should function, what management protocol to use, how to enhance the flexibility and how to make the system more secure.

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Ho, Yao. "CONNECTIONLESS APPROACH – A LOCALIZED SCHEME TO MOBILE AD HOC NETWORKS." Doctoral diss., University of Central Florida, 2009. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2763.

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According to a Gartner Group (www.gartner.com) report in September 2008, the worldwide telecommunications market is on pace to reach $2 trillion in 2008. Gartner predicts that by 2012, the ratio of mobile to fixed connections will exceed 4-to-1. The North American mobile data market grew to 141.1 million connections in 2007, with a compound annual growth rate of 41.7 percent. It is believed that a large portion will be ad hoc and multi-hop connections, which will open many opportunities for Mobile Ad hoc NETwork (MANET) applications and Wireless Mesh Network (WMN) applications. A MANET is a self-organizing multi-hop wireless network where all nodes participate in the routing and data forwarding process. Such a network can be easily deployed in situations where no base station is available, and a network must be build spontaneously. In applications such as battlefield communications, national crises, disaster recovery, and sensor deployment, a wired network is not available and ad hoc networks provide the only feasible means of communications and information access. Ad hoc networks have also become commonplace for gaming, conferencing, electronic classrooms, and particularly vehicle-to-vehicle communications. A Wireless mash network (WMN) is collection of mesh clients and mesh nodes (routers), with mesh nodes forming the backbone of the network and providing connection to the Internet and other network. Their rapid deployment and ease of maintenance are suitable for on-demand network such as disaster recovery, homeland security, convention centers, hard-to-wire buildings and unfriendly terrains. One important problem with MANET is the routing protocol that needs to work well not just with a small network, but also sustain efficiency and scalability as the network gets expanded and the application transmits data in greater volume. In such an environment, mobility, channel error, and congestion are the main causes for packet loss. Due to mobility of mobile hosts, addressing frequent and unpredictable topology changes is fundamental to MANET research. Two general approaches have been considered: connection-oriented approach and connectionless-oriented approach. In the former, the emphasis is on how to reconnect quickly with low overhead when a broken link occurs. Examples of this approach includes , , , , , , , , , and . In contrast, connectionless-oriented approach focuses on minimizing the occurrence of broken links. We proposed one such scheme called Connectionless Approach (CLA) and . In CLA, the network area is divided into non-overlapping grid cells, each serving as a virtual router. Any physical router (i.e., mobile host), currently inside a virtual router, can help forward the data packet to the next virtual router along the virtual link. This process is repeated until the packet reaches its final destination. Since a virtual link is based on virtual routers which do not move, it is much more robust than physical links used in the connection-oriented techniques. Simulation results in our previous works and , based on GloMoSim , indicate that CLA performs significantly better than connection-oriented techniques (i.e., AODV, DSR, LAR, GRID, TMNR, and GPSR). The contribution of this work consists of investigating and developing new Connectionless-Oriented Approach for Mobile Ad Hoc Network. Two of the greatest impacts of this research are as follows. First, the new approach is targeted towards robustly support high mobility and large scale environment which has been adapted for vehicle-to-vehicle environment in . Second, the detailed simulations which compare eight representative routing protocols, namely AODV, DSR, LAR, GRID, TMNR, GPSR, CBF, and CLA, under high-mobility environments. As many important emergent applications of the technology involved high-mobility nodes, very little is known about the existing routing methods perform relative to each other in high-mobility environments. The simulation results provide insight into ad hoc routing protocols and offer guidelines for mobile ad hoc network applications. Next, we enhanced and extend the connectionless-oriented approach. The current connectionless-oriented approach, however, may suffer from packet drops since traffic congestion is not considered in the packet forwarding policy. We address this weakness by considering the connectionless-oriented approach with a collision avoidance routing technique. After that, we investigate techniques to enforce collaboration among mobile devices in supporting the virtual router functionality. Many works have been published to combat such problem - misbehaving nodes are detected and a routing algorithm is employed to avoid and penalize misbehaving nodes. These techniques, however, cannot be applied to the connectionless-oriented approach since any node in the general direction towards the destination node can potentially help forward the data packets. To address the security and cooperation issues for connectionless-oriented approach, we introduce a cooperation enforcement technique called 3CE (3-Counter Enforcement). In addition, wireless mesh networks have become increasingly popular in recent years. Wireless mash network (WMNs) are collection of mesh clients and mesh nodes (routers), with mesh nodes forming the backbone of the network and providing connection to the Internet and other network. We propose a paradigm that combines virtual routers and mesh nodes to create a hybrid network call VR-Mesh Network. This hybrid network can reduce number of mesh node needed without decrease the performance of the network. Ph.D. School of Electrical Engineering and Computer Science Engineering and Computer Science Computer Science PhD

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Tilley, Kevin Joseph. "Performance of computer communications for manufacturing." Thesis, University of Cambridge, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386857.

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Lent, Marino Ricardo. "On the design and performance of cognitive packets over wired networks and mobile ad hoc networks." Doctoral diss., University of Central Florida, 2003. http://digital.library.ucf.edu/cdm/ref/collection/RTD/id/3553.

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University of Central Florida College of Engineering Thesis This dissertation studied cognitive packet networks (CPN) which build networked learning systems that support adaptive, quality of service-driven routing of packets in wired networks and in wireless, mobile ad hoc networks. Ph.D. School of Electrical Engineering and Computer Science Engineering and Computer Science Electrical Engineering and Computer Science 160 p. xvii, 160 leaves, bound : ill. ; 28 cm.

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Caulkins, Bruce. "SESSION-BASED INTRUSION DETECTION SYSTEM TO MAP ANOMALOUS NETWORK TRAFFIC." Doctoral diss., University of Central Florida, 2005. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3466.

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Computer crime is a large problem (CSI, 2004; Kabay, 2001a; Kabay, 2001b). Security managers have a variety of tools at their disposal firewalls, Intrusion Detection Systems (IDSs), encryption, authentication, and other hardware and software solutions to combat computer crime. Many IDS variants exist which allow security managers and engineers to identify attack network packets primarily through the use of signature detection; i.e., the IDS recognizes attack packets due to their well-known "fingerprints" or signatures as those packets cross the network's gateway threshold. On the other hand, anomaly-based ID systems determine what is normal traffic within a network and reports abnormal traffic behavior. This paper will describe a methodology towards developing a more-robust Intrusion Detection System through the use of data-mining techniques and anomaly detection. These data-mining techniques will dynamically model what a normal network should look like and reduce the false positive and false negative alarm rates in the process. We will use classification-tree techniques to accurately predict probable attack sessions. Overall, our goal is to model network traffic into network sessions and identify those network sessions that have a high-probability of being an attack and can be labeled as a "suspect session." Subsequently, we will use these techniques inclusive of signature detection methods, as they will be used in concert with known signatures and patterns in order to present a better model for detection and protection of networks and systems. Ph.D. Other Arts and Sciences Modeling and Simulation

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Stienmetz, Jason Lee. "Foundations for a Network Model of Destination Value Creation." Diss., Temple University Libraries, 2016. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/419874.

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Tourism and Sport Ph.D. Previous research has demonstrated that a network model of destination value creation (i.e. the Destination Value System model) based on the flows of travelers within a destination can be used to estimate and predict individual attractions’ marginal contributions to total visitor expenditures. While development to date of the Destination Value System (DVS) has focused on the value created from dyadic relationships within the destination network, previous research supports the proposition that system-level network structures significantly influence the total value created within a destination. This study, therefore, builds upon previous DVS research in order to determine the relationships between system-level network structures and total value creation within a destination. To answer this question econometric analysis of panel data covering 43 Florida destinations over the period from 2007 to 2015 was conducted. The panel data was created utilizing volunteered geographic information (VGI) obtained from 4.6 million photographs shared on Flickr. Results of econometric analysis indicate that both seasonal effects and DVS network structures have statistically significant relationships with total tourism-related sales within a destination. Specifically, network density, network out-degree centralization, and network global clustering coefficient are found to have negative and statistically significant effects on destination value creation, while network in-degree centralization, network betweenness centralization, and network subcommunity count are found to have positive and statistically significant effects. Quarterly seasonality is also found to have dynamic and statistically significant effects on total tourism-related sales within a destination. Based on the network structures of destinations and total tourism related sales within destinations, this study also uses k-means cluster analysis to classify tourism destinations into a taxonomy of six different system types (Exploration, Involvement, Development I, Development II, Consolidation, and Stars). This taxonomy of DVS types is found to correspond to Butler’s (1980) conceptualization of the destination life cycle, and additional data visualization and exploration based on the DVS taxonomy finds distinct characteristics in destination structure, dynamics, evolution, and performance that may be useful for benchmarking. Additionally, this study assesses the quality of VGI data for tourism related research by comparing DVS network structures based on Flickr data and visitor intercept survey data. Support for the use of VGI data is found, provided that thousands of observations are available for analysis. When fewer observations are available, aggregation techniques are recommended in order to improve the quality of overall destination network system quantification. This research makes important contributions to both the academic literature and the practical management of destinations by demonstrating that DVS network structures significantly influence the economic value created within the destination, and thus suggests that a strategic network management approach is needed for the governance of competitive destinations. As a result, this study provides a strong foundation for the DVS model and future research in the areas of destination resiliency, “smarter” destination management, and tourism experience design. Temple University--Theses

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Dissertations / Theses on the topic 'CPM network'

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