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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Spatial Modeling of Wildlife Crossing:GIS-based Approach for Identifying High-priority Locations of Defragmentation across Transport Corridors / Rumslig Modellering av Ekodukt: GIS-baserad Modellering för att identifiera Habitat Flaskhalsar Längst en Transport Korridor.

Jonsson, Josefine January 2017 (has links)
In this report, connectivity modeling has been performed using land cover data to find habitat pinch-points for deer along the study area Norrortsleden in Stockholm. Norrortsleden was chosen because there are a high number of deer accidents in the area, and is a priority area for action according to a barrier analysis for deer made by the Swedish Transport Administration. After interviews and research, it was found that a tool named LinkageMapper using CircuitScape theory is one good way to find habitat pinch-points along transport corridors. Firstly, a habitat resistance raster map and zone data are needed. The habitat resistance layer was made using ground cover data and given resistance values specifically for deer. An edge-zone layer was also added on top using built-in ArcGIS tools. Lastly all the road and railway data was transformed into raster and added to the final resistance layer. To find the pinch-points in the natural habitat for deer, different settings for the ArcGIS tool LinkageMapper have been tested and variations of the zone layer have been used. LinkageMapper is an external free to download tool and uses CircuitScape theory to find habitat pinch points. Different settings were tested for a 2-zone version on a 2 km buffer on each side of the road. In addition, two main settings are available, all-to-one mode and pairwise mode in LinkageMapper. Input width must also be entered to limit the number of results. Corridor width was set to 50 m for all of the produced results. After preparation of the raw data, processing zones and resistance layers it was found that usually only one corridor was showing, so a version with 6 zones on each side of the road with a 4 km buffer was made and produced more continuous results. All of the pinch-points found were marked on a map and the ones not already near an existing wildlife passage are located just south of Lake Vallentuna. The research found that the GIS-based approach is effective for Identifying high-priority locations of defragmentation across transport corridors. Using CircuitScape theory can be a great compliment too regular least cost-path.
2

Proximity based association rules for spatial data mining in genomes

Saha, Surya 08 August 2009 (has links)
Our knowledge discovery algorithm employs a combination of association rule mining and graph mining to identify frequent spatial proximity relationships in genomic data where the data is viewed as a one-dimensional space. We apply mining techniques and metrics from association rule mining to identify frequently co-occurring features in genomes followed by graph mining to extract sets of co-occurring features. Using a case study of ab initio repeat finding, we have shown that our algorithm, ProxMiner, can be successfully applied to identify weakly conserved patterns among features in genomic data. The application of pairwise spatial relationships increases the sensitivity of our algorithm while the use of a confidence threshold based on false discovery rate reduces the noise in our results. Unlike available defragmentation algorithms, ProxMiner discovers associations among ab initio repeat families to identify larger more complete repeat families. ProxMiner will increase the effectiveness of repeat discovery techniques for newly sequenced genomes where ab initio repeat finders are only able to identify partial repeat families. In this dissertation, we provide two detailed examples of ProxMiner-discovered novel repeat families and one example of a known rice repeat family that has been extended by ProxMiner. These examples encompass some of the different types of repeat families that can be discovered by our algorithm. We have also discovered many other potentially interesting novel repeat families that can be further studied by biologists.
3

Redes definidas por software na flexibilização de centrais de dados para sistemas de computação em nuvem

Lopes, Robson Ferreira January 2014 (has links)
Orientadora: Profª. Drª. Christiane Marie Schweitzer / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Engenharia da Informação, 2014. / Os sistemas em nuvem representam uma nova solução para provedores de serviços de rede para empresas de pequeno e médio porte. Esses provedores possuem centrais de dados com grande quantidade de servidores, instalados sobre uma estrutura virtualizada e que permite a alocação dos espaços para diversas empresas que tem necessidade de hospedagem de serviços e dados e não possuem recursos financeiros para sua própria central de dados. Por meio das Redes Definidas por Software (Software Defined Networks - SDN) o plano de controle está separadodo plano de dados fazendo surgir uma nova solução de operação e gerenciamento das redes. Oplano de dados é composto por switches, roteadores e hosts, responsável pelo tráfego dainformação através de seus fluxos, enquanto o plano de controle é implementado emsoftwaree é responsável pelo roteamento de pacotes e arquitetura. Os controladores são responsáveispela manutenção dos fluxos. Atualmente os controladores disponíveis para utilização e decódigo aberto, são: NOX, POX, Maestro, Beacon e Floodlight. Assim, o uso de SDN emsistemas de computação em nuvem, permite uma flexibilização da operação e gerenciamentode centrais de dados. Neste sentido, este trabalho procurou avaliar a resistência de controladoresSDNs diante de ataques de negação de serviço, que possam interromper seu funcionamento,comprometendo a segurança da rede, por meio de testes constatou-se que o controlador NOXapresentou um comportamento bastante satisfatório, mantendo as conexões de rede ativas sobstress. Além disso, diante do problema que administradores de centrais de dados se defrontamquando precisam alocar ou aumentar as máquinas virtuais no conjunto de servidores da nuvem,nem sempre é possível alocar máquinas virtuais próximas umas das outras no mesmo servidor,interferindo na vazão da rede, foi investigada uma solução para permitir esta reorganização.Esta solução foi chamada de desfragmentador de redes e permite o deslocamento das máquinasvirtuais, fazendo com que sejam alocadas em um único conjunto físico de servidores. Estareorganização é feita sob demanda e em tempo real, e os resultados apresentados são bastante interessantes mostrando a viabilidade da solução. / Cloud systems represent a new solution for network service providers for small and mid-sized companies. These providers have datacenters with large amount of servers, installed on a virtualized structure and allowing the allocation of spaces for several companies that have needof hosting services and data and they do not have the financial resources to your own datacenter. In the Software Defined Networks (SDNs), the control plane is separated from the data plan making a new solution of networks operation and management. The data plan is composed of switches, routers and hosts, responsible for the traffic information through its streams, while the control plan is implemented in software and is responsible for the architecture and routing of packets. Controllers are responsible for the management of the streams. Currently, the available controllers, for use and open source, are: NOX, POX, Maestro, Beacon and Floodlight. Thus, the use of SDN, in cloud computing systems, allows a flexibility of operation and management of datacenters. In this sense, this work sought to evaluate the resistance of SDNs controllers in front of denial-of-service attacks that can disruptits operation, compromising network security, by testing it was found that the NOX controllerpresented a quite satisfying behavior, keeping active network connections under stress.Moreover, faced with the problem that datacenter administrators when they need to allocate orincrease the virtual machines in the cloud servers, it is not always possible to allocate virtualmachines near to each other on the same server, interfering with network flow, was investigateda solution to allow this reorganization. This solution was called the network defragmenter and allows the movement of virtual machines, which are allocated on a single set of physical servers. This reorganisation is made on demand and in real time, and the results are quite interesting, showing the viability of the solution.
4

Defragmenting Identity in the Life Narratives of Iraqi North American Women

Al Ethari, Lamees 29 April 2014 (has links)
This dissertation examines contemporary Iraqi North American women’s life narratives within the frame of postcolonial autobiography theory. Through narrating their experiences of oppression, war, and displacement these women reveal the fragmentation of identity that occurs under such unsettling situations. However, I argue that in the course of narrating their stories and in spite of the fragmentation they suffer, these women are able to establish selves that distinguish and recover from fragmentation and loss through a process I term defragmentation. They are able to defragment their identities by reconstructing unique selves through the act of life narration, through relational remembering, and finally by resisting patriarchal and Western influences on how they perceive themselves and their experiences. Thus they are able to defragment their sense of disjointedness and reaffirm their sense of Iraqiness, even in the diaspora. This study explores the major causes of fragmentation in the work, which are divided into trauma and displacement. Unlike the studies and statistics that political approaches and media coverage have provided, these works shed light on the disruptions caused by war, oppression, separation from loved ones, and exile in the daily lives of these narrators or the lives of their friends and relatives. Therefore, in addition to the new identity that these women create in order to cope with their new lives in the West, they also construct a hybrid identity that is capable of recollecting and narrating these traumatic experiences. Within the space of hybridity, Iraqi North American women have to deal with vast differences between Western and Middle Eastern cultures; the transformation entails not just a change of place but an acceptance or understanding of a new culture, a new religion, and a new identity. The struggle of settlement, or re-settlement, becomes that of establishing an identity that does reflect the stereotypical images of Middle Eastern women in Western perceptions and a struggle to maintain selves that can contain both the past life and the present in what can be considered a third space. Although the main topic of this dissertation is defragmentation in the life narrations of Iraqi North American women, this study also covers the cultural and political history of Arabs in general, and of Iraqis specifically. There are also references to the migrations of Arabs to North America and a brief background of the roots of Arab North American literature. These topics will be discussed in order to provide an understanding of the histories from which these women, or their families, have migrated and their positions within Western culture and scholarship. In addition, this approach provides an insight into the complexities of these women’s identities that reflect multi-layered affiliations, interests, and cultures. The works chosen for this study include written and oral life narratives by Iraqi North American women who write from Canada and the United States. These works are Zaineb Salbi’s Between Two Worlds: Escape From Tyranny: Growing Up in the Shadow of Saddam (2005), Dunya Mikhail’s A Diary of a Wave Outside the Sea (2009) and a National Film Board documentary titled Baghdad Twist (2007), by Jewish Iraqi Canadian Joe Balass. In the documentary, Joe Balass interviews his mother, Valentine Balass, as she recounts growing up in Iraq and later experiencing exile from her homeland. The final work I address is The Orange Trees of Baghdad: In Search of My Lost Family (2007) by Leilah Nadir, a Canadian born Iraqi writer. Through her memoir Nadir tries to reconnect with her father’s family in Iraq while uncovering their traumatic experiences of the Gulf War. The narrators in my research belong to different social classes, age groups, and practice different religions, but they all identify themselves as Iraqi women. These women, through their interpretations of living life between two (or more) cultures, offer important perspectives not only on their own ethnic society, but also on the role of ethnic women in North American society in general. There has been a massive increase in the migration of Iraqi women to North America in the last thirty years; their perspectives on political, social, and religious changes are an important part of understanding the experiences of this ethnic group. Through their life narratives, these women are able to display their unique selves by portraying their ability to contest the boundaries and limitations of borders and societies that try to eliminate one identity or the other.
5

Análise de desempenho em redes ópticas elásticas operando com algoritmos para alocação eficiente de espectro

Deffert, Mauricio Antonio January 2017 (has links)
Orientador: Prof. Dr. Luiz Henrique Bonani do Nascimento / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Engenharia da Informação, 2016. / As redes ópticas são fundamentais para o transporte de informação, que sofrem um rápido crescimento nos dias atuais. Com o advento de novos serviços, redes sociais, diversos equipamentos conectados, tráfego multimídia, vídeo sob demanda, entre outros, o tráfego de informações tem crescido e as Redes Ópticas têm tido um papel de transporte muito importante garantindo a qualidade dos serviços oferecidos. A tecnologia das redes ópticas elásticas (Elastic Optical Networks (EON)s), trazem novas pesquisas para uma melhor otimização de largura de banda no espectro óptico. O estudo tem a finalidade de avaliar, com o uso de simulação, três novos algoritmos de melhor ocupação espectral desenvolvidos neste trabalho, comparados com o algoritmo First Fit (FF) existente na literatura, em termos de tipos de serviços e número de rotas, utilizando duas topologias físicas distintas. Com os algoritmos de melhor ocupação espectral, será realizada a atribuição de serviços e a organização de todos os espaços (slots) da banda C de 4,4 THz, permitindo um melhor aproveitamento e flexibilidade do espectro total, pois o mesmo apresenta espaços não contíguos de largura de banda ao longo do tempo, gerando a Probabilidade de Bloqueio (Blocking Probability (PB)) e a fragmentação da rede óptica. Os algoritmos propostos apresentaram melhores resultados comparados com o algoritmo FF. / The Optical Networks are fundamental for the transport of information, which are experiencing rapid growth in the present days. With the advent of new services, social networks, several connected equipment, multimedia traffic, video on demand, among others, information traffic has grown and the Optical Networks have played a very important transport role guaranteeing the quality of services offered. The technology of elastic optical networks (EON), bring new research for a better optimization of bandwidth in the optical spectrum. The purpose of this study was to evaluate the use of simulation in three new spectral optimization algorithms developed in this work, compared to the First Fit algorithm existing in the literature, in terms of service types and number of routes, using two different physical topologies. With the algorithms of better spectral occupation, the assignment of services and the organization of all slots of the C band of 4.4 THz will be realized, allowing a better utilization and flexibility of the total spectrum, since the same presents uncontiguous bandwidth spaces over time, generating the Blocking Probability and the fragmentation of the optical network. The proposed algorithms presented better results compared to the First Fit algorithm.
6

Compara??o de estrat?gias de acomoda??o espectral e desfragmenta??o em redes ?pticas el?sticas / Accommodation strategies comparison spectral and defragmentation in elastic optical networks

Mar?al, Juliano Silva 27 June 2016 (has links)
Submitted by Fernanda Ciolfi (fernanda.ciolfi@puc-campinas.edu.br) on 2016-08-16T18:29:14Z No. of bitstreams: 1 Juliano Silva Mar?al.pdf: 14418180 bytes, checksum: e94d4d5adc61aeda0c174d60cabfa216 (MD5) / Made available in DSpace on 2016-08-16T18:29:14Z (GMT). No. of bitstreams: 1 Juliano Silva Mar?al.pdf: 14418180 bytes, checksum: e94d4d5adc61aeda0c174d60cabfa216 (MD5) Previous issue date: 2016-06-27 / Pontif?cia Universidade Cat?lica de Campinas ? PUC Campinas / In the current technological environment from the point of view of optical transmission, multiplexing technologies for wavelength division (Wavelength Oivision Multiplexing - WOM) working with fixed 50 GHz grid will not support the existing demand for the next 10 years. This scarcity occurs due to several reasons: channels with fixed width of 50 GHz, limitation of 80 optical channels per link, maximum transmission capacity of 100 Gb / s per channel. In search of viable forward solutions to this paradigm that presents technology proposal comes known as Optical Networks Elastic (Elastic Optical Network - EON), a technology that enables optical channels with bandwidths of 3,125, 6,250, 12,500, 25 and 50 GHz transmission capability of rates supported by the WOM yet rates of 200 Gb / s, 400 Gb / s and 1 Tb / s, and can be implemented on the same optical infrastructure WOM already existing thus corresponding to a highly cost less if compared to deployment of new networks. The efficiency of this proposed new technology is mainly in routing algorithms and spectral assignment (Routing and Spectrum Assignment - RSA) aimed at maximizing network availability of resources by reducing the likelihood of blocking. The use of RSAs on the EONS networks fragmentation results in the generation of reducing the availability of network resources. Within this scenario, the present work-studies the feasibility of defragmentation use based on the relocation of the link to submit further fragmentation indexo This paper studies the adoption of two indices: consecutiveness index and more FSUs index busy, both indexes allow the selection of the link to be defragmented. The results of this study were obtained from the development of version 5 of the simulator Elastic Optical Network Simulator (EONSim). To obtain the results, different transmission rates were evenly distributed for each traffic load between 45 and 100 Erlang (E), the First-Fit RSA (FF) was adopted for ali the simulations to reduce the defragmentation processing were performed from an R number of released connections (R = 10, R = 50 and R = 100). For the scenario using the consecutiveness index gain of up to 44 was measured to 55 E and average gain of 15 compared to results without defragmentation scenario for the use of higher index number of occupied FSUs, gain was observed 26 to 55 E and average gain of 10. From the results it can be concluded that the adoption of defragmentation strategies for eons networks are likely to be used since they have decreased blocking probability and increase the availability of network resources. / Na atual conjuntura tecnol?gica do ponto de vista de transmiss?es ?pticas, as tecnologias de multiplexa??o por divis?o de comprimento de onda (Wavelength Oivision Multiplexing - WOM) que trabalham com grade fixa de 50 GHz n?o ir?o comportar a demanda existente para os pr?ximos 10 anos. Esta escassez ocorre por v?rios motivos: canais com largura fixa de 50 GHz, limita??o de 80 canais ?pticos por enlace, capacidade m?xima de transmiss?o de 100 Gb/s por canal. Em busca de solu??es vi?veis frente a este paradigma que se apresenta, surge a proposta da tecnologia conhecida como Redes ?pticas El?sticas (Elastic Optical Network- EON), uma tecnologia que permite canais ?pticos com larguras de banda de 3.125, 6.250, 12.500, 25 e 50 GHz, capacidade de transmiss?o das taxas suportadas pela tecnologia WDM e ainda taxas de 200 Gb/s, 400 Gb/s e 1 Tb/s, e podem ser implantadas sobre a mesma infraestrutura ?ptica WDM j? existente correspondendo assim a um custo altamente inferior se comparado a implanta??o de novas redes. A efici?ncia desta nova proposta de tecnologia est? principalmente nos algoritmos de roteamento e atribui??o espectral (Routing and Spectrum Assignment - RSA) que visam a maximiza??o dos recursos de disponibilidade da rede atrav?s da diminui??o da probabilidade de bloqueio. O uso do RSA resulta na gera??o de fragmenta??o diminuindo a disponibilidade de recursos da rede. Dentro deste cen?rio, o presente trabalho estuda a viabilidade do uso de desfragmenta??o baseada na realoca??o sobre o enlace que apresentar maior ?ndice de fragmenta??o e analisa a ado??o de dois ?ndices: ?ndice de consecutividade e ?ndice de maior n?mero de FSUs ocupados, para a sele??o do enlace a ser desfragmentado. Os resultados deste estudo foram obtidos a partir do desenvolvimento da vers?o 5 do simulador Elastic Op tica I Network Simulator (EONSim). Para a obten??o dos resultados, diferentes taxas de transmiss?o foram distribu?das uniformemente para cada uma carga de tr?fego entre 45 e 100 erlang (E), o RSA First-Fit (FF) foi adotado para todas as simula??es, para diminuir o processamento as desfragmenta??es foram executadas a partir de um n?mero R de conex?es liberadas (R= 10, R= 50 e R= 100). Para o cen?rio utilizando o ?ndice de consecutividade, foi aferido ganho de at? 44 para 55 E e ganho m?dio de 15 quando comparado aos resultados do cen?rio sem desfragmenta??o, para o uso do ?ndice de maior n?mero de FSUs ocupados, foi observado ganho de 26 para 55 E com ganho m?dio de 10. A partir dos resultados obtidos ? poss?vel concluir que a ado??o de estrat?gias de desfragmenta??o para redes EONs s?o pass?veis de serem utilizadas pois apresentam diminui??o da probabilidade de bloqueio e aumento da disponibilidade dos recursos da rede
7

Nova estrat?gia de desfragmenta??o de canais para redes ?pticas el?sticas / A New elastic optical network defragmentation of channels strategy

F?vero, Ricardo Vicente 13 November 2015 (has links)
Made available in DSpace on 2016-04-04T18:31:45Z (GMT). No. of bitstreams: 1 RICARDO VICENTE FAVERO.pdf: 1635235 bytes, checksum: d51f441103ff9f2ad94576b0bdd11b9f (MD5) Previous issue date: 2015-11-13 / The wavelength division multiplexing (WDM) optical network accommodates traffic load in 100, 50 and 25 GHz fixed-grid channel. This fixed-grid condition limits the number of lightpath for each optical fiber (80 channels in c-band) and doesn t allow bit rates with bandwidth over 50 GHz. To improve these factors, the flexibly grid elastic optical network (EON) was proposed, aiming accommodate adequately bit rates demand by customers. This proposal allows efficiency bandwidth and also expands bit rates supported by network. The EON bandwidth efficiency is obtained by routing and spectrum assignment (RSA) algorithm which acts to maximize the bandwidth utilization. Even with RSA, EON still show fragmentation rates substantial. In this context, this work proposes a new elastic optical network defragmentation strategy. This defragmentation strategy selects the lightpaths from the most fragmented link. The defragmentation process is based on RSA (DF-RSA). The DF-RSA determines the new position to reallocate the connection selected and performs. Using computer simulation of EON operation, were submitted several bit rates demands with different modulations format and traffic load between 45 and 100 erlang. Two simulation scenarios were proposed. The first one, compare the performance of RSA algorithm first-fit (FF) with and without defragmentation. It was considered as defragmentation process beginning point (trigger), the number of release connections. This scenario had until 48% of relative gain on minimizing blocking probability. The second scenario compared the performance of the follows RSA algorithms: FF, Maximize Path Spectrum Consecutiveness (MPSC) and Fragmentation Aware (FA). The FF was evaluated with and without defragmentation process and the others just with defragmentation process. The trigger employed was eventual connection blocked. The second scenario reached over the 80% blocking probability relative gain in 50 erlang traffic load. We conclude that the new elastic optical network defragmentation offers substantial gain bandwidth utilization and consequently blocking probability reduction. / As redes ?pticas de multiplexa??o por divis?o de comprimento de onda (WDM) acomodam o tr?fego em canais fixos de 100, 50 e 25 GHz. Esta condi??o de grade fixa limita o n?mero de conex?es por fibra ?ptica (80 canais na banda C), e n?o permite taxas de transmiss?o com ocupa??o espectral acima de 50 GHz. Para melhorar estes fatores, foram propostas as redes ?pticas el?sticas (EON) com canais flex?veis, visando acomodar adequadamente as taxas de transmiss?o demandas pelos usu?rios. Esta proposta possibilita maior efici?ncia espectral e tamb?m amplia as taxas de transmiss?o suportadas pela rede. A efici?ncia espectral nas EONs ? obtida com os algoritmos de roteamento e atribui??o espectral (Routing and Spectrum Assignment, RSA), que atuam para maximizar seu uso espectral. Mesmo com o uso de RSAs, as EONs ainda apresentam ?ndices de fragmenta??o consider?veis. Neste contexto, este trabalho prop?e uma nova estrat?gia de desfragmenta??o espectral para EONs. Esta proposta de desfragmenta??o seleciona as conex?es do enlace mais fragmentado, para o processo de desfragmenta??o. A desfragmenta??o baseia seu processo de realoca??o de conex?es por RSA, denominado DF-RSA. O DF-RSA determina a nova posi??o e realiza a realoca??o das conex?es. Com o uso de simula??o computacional da opera??o de funcionamento da EON, foram submetidas v?rias demandas de taxas de transmiss?o com diferentes modula??es e cargas de tr?fego entre 45 e 100 erlang. Foram propostos dois cen?rios de simula??o. No primeiro, foi comparado o desempenho do algoritmo RSA First-Fit (FF) com e sem o processo de desfragmenta??o. Considerou-se como ponto de inicio das desfragmenta??es (gatilho), o n?mero de conex?es liberadas da rede. Neste cen?rio obteve-se at? 48% de ganho relativo na minimiza??o da probabilidade de bloqueio. No segundo cen?rio, foram comparados os desempenhos dos seguintes algoritmos RSAs: FF, Maximize Path Spectrum Consecutiveness (MPSC) e Fragmentation Aware (FA). O FF foi avaliado com e sem desfragmenta??o e os demais somente com desfragmenta??o. Empregou-se como gatilho o eventual bloqueio de conex?o. O segundo cen?rio alcan?ou mais de 80% de ganho relativo de probabilidade de bloqueio para carga de tr?fego de 50 erlang. Conclui-se que a nova estrat?gia de desfragmenta??o para EONs oferece ganhos consider?veis na utiliza??o espectral e, consequentemente, redu??o na probabilidade de bloqueio.
8

Quantification of Potential Ecological Impacts of Road Transport

Friedrich, Jan 16 June 2014 (has links)
No description available.
9

Pokročilé nástroje pro měření výkonu / Advanced Tools for Performance Measurement

Smrček, Jaromír January 2008 (has links)
This thesis presents the I/O layer of Linux kernel and shows various tools for tuning and optimization of its performance. Many tools are presented and their usage and outputs are studied. The thesis then focuses on the means of combining such tools to create more applicable methodology of system analysis and monitoring. The practical part consists of applying SystemTap scripts for blktrace subsystem and creating a fragmentation monitoring tool with graphical output.

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