A primary challenge in wireless networks is to use available resources efficiently so that the Quality of Service (QoS) is satisfied while maximizing the throughput of the network. Among different resource allocation strategies, power and spectrum allocations have long been regarded as efficient tools to mitigate interference and improve the throughput of the network. Also, achieving a low transmission delay is an important QoS requirement in buffer-limited networks, particularly for users with real-time services. For these networks, too much delay results in dropping some packets. Therefore, the main challenge in networks with real-time services is to utilize an efficient power allocation scheme so that the delay is minimized while achieving a high throughput. This dissertation deals with these problems in distributed wireless networks.

FREITAS, Cley Anderson Silva De. Comportamento de três cultivares de mamona a cinco níveis de irrigação por gotejamento em Pentecoste, CE. 2009. 69 f. Dissertação (Mestrado em engenharia agrícola)- Universidade Federal do Ceará, Fortaleza-CE, 2009. / Submitted by Elineudson Ribeiro (elineudsonr@gmail.com) on 2016-06-17T17:20:15Z No. of bitstreams: 1 2009_dis_casfreitas.pdf: 1553059 bytes, checksum: 97d84b9326bf21b24b9037c5fff0106a (MD5) / Approved for entry into archive by José Jairo Viana de Sousa (jairo@ufc.br) on 2016-07-21T20:04:23Z (GMT) No. of bitstreams: 1 2009_dis_casfreitas.pdf: 1553059 bytes, checksum: 97d84b9326bf21b24b9037c5fff0106a (MD5) / Made available in DSpace on 2016-07-21T20:04:23Z (GMT). No. of bitstreams: 1 2009_dis_casfreitas.pdf: 1553059 bytes, checksum: 97d84b9326bf21b24b9037c5fff0106a (MD5) Previous issue date: 2009 / The use of the irrigation in cultivars improved has a tendency to favor the increase of the productivity of castor in the semi-arid. This work was carried out in Fazenda Experimental Vale do Curu, Pentecoste, Ceará, Brazil and the objective of the present study was to evaluate the productive characteristics of three castor cultivars of high agricultural importance (IAC Guarani, Mirante 10 e BRS Paraguaçu) under different levels of irrigation. The experimental delineation used was of the blocks at random with subdivided parcels, composed of five treatments in the parcels, with three cultivars in the sub parcels and three repetitions. The treatments was constituted in five levels of irrigation based on the evaporation of the tank Class “A” ECA (T1 = 0,25 ECA; T2 = 0,50 ECA; T3 = 0,75 ECA; T4 = 1,00 ECA; T5 = 1,25 ECA). The result, found a significant effect between cultivars. The variables length and number of fruits per racemes were higher for the IAC Guarani, while the tenor of oil and number of racemes per plant were higher for the Mirante 10. However the Paraguaçu BRS stood out of the rest of cultivars as for the mass of the raceme, mass of the fruits, mass of hundred seeds and productive potential. There was no significant effect of variable tenor of oil with the blades of irrigation. The Mirante 10 presented the largest tenor of oil (40,64 %), with the maximum blade used of 913,4 mm. The best efficiency of the use of the water was obtained by the treatment T5 (913,4 mm) in the BRS Paraguaçu, what turned the productivity of 2872,42 Kg ha -1. The secondary racemes were that more contributed with the total productivity. / O uso da irrigação em cultivares melhoradas tende a favorecer o aumento da produtividade da mamoneira no semi-árido. Assim, esta pesquisa teve como objetivo avaliar o comportamento das variáveis produtivas de três cultivares de mamoneira de importância agrícola (IAC Guarani, Mirante 10 e BRS Paraguaçu) a cinco níveis de irrigação por gotejo. O experimento foi realizado na Fazenda Experimental Vale do Curu, Pentecoste, Ceará, Brasil. O delineamento experimental foi o de blocos ao acaso com parcelas subdivididas, composto de cinco tratamentos nas parcelas, com três cultivares nas subparcelas e três repetições. Os tratamentos constituíram-se em cinco níveis de irrigação baseados na evaporação do tanque Classe “A” ECA (T1 = 0,25 ECA; T2 = 0,50 ECA; T3 = 0,75 ECA, T4 = 1,00 ECA; T5 = 1,25 ECA). Houve diferença estatística entre as cultivares, as variáveis comprimento e número de frutos por racemos foram maiores para a cultivar IAC Guarani, enquanto o teor de óleo e número de racemos por planta foram maiores para cultivar Mirante 10. Já a BRS Paraguaçu destacou-se das demais cultivares quanto a massa do racemo, massa dos frutos, massa de cem sementes e potencial produtivo. Não houve efeito significativo da variável teor de óleo com as lâminas de irrigação. Verifica-se maior teor de óleo (40,64 %), nas sementes da cv. Mirante 10, com a lâmina máxima aplicada de 913,4 mm. A melhor eficiência do uso da água foi obtida com o tratamento T5 (913,4 mm) na cultivar BRS Paraguaçu, que resultou na produtividade de 2872,42 kg ha-1. Os racemos secundários foram os que mais contribuíram com a produtividade total.

RESUMO Esta dissertaÃÃo procurou identificar os fatores que influenciaram, mais fortemente, os alunos evadidos dos cursos de nÃvel mÃdio integrados à formaÃÃo profissional na modalidade EJA, no Instituto Federal do Cearà (IFCE) - campus de Fortaleza. Na busca de aumentar as chances de encontrar respostas mais confiÃveis e consistentes, procurou-se trabalhar com todos os segmentos envolvidos no processo pedagÃgico: evadidos, alunos, professores, administradores e pedagoga. A pesquisa se caracterizou como um estudo de caso, empÃrica, do tipo explicativa, descritiva, e pretendeu analisar: a) o desenvolvimento do currÃculo, b) a dinÃmica do relacionamento professor/aluno, c) as condiÃÃes de infraestrutura do IFCE para o bom desempenho dos cursos e d) as questÃes de maior relevÃncia que motivam o abandono por parte do aluno. O procedimento metodolÃgico da investigaÃÃo decorreu no recorte temporal entre 2009 e 2011 e se realizou em trÃs tempos e formas: pesquisa bibliogrÃfica, documental e de campo, subsidiadas pelas tÃcnicas de grupo focal, de observaÃÃo participante e de entrevistas semiestruturadas, junto aos segmentos investigados. Buscando uma fundamentaÃÃo para os possÃveis achados, foi feita uma revisÃo sobre as trajetÃrias da EJA e do ensino profissional no Brasil, caracterizou-se o IFCE, e realizou-se uma rÃpida incursÃo sobre o IFCE - campus de Fortaleza, o seu PROEJA e em particular sobre o perfil de seus alunos. Considerou-se como fundamentos teÃricos, trabalhos de Makarenko (1987), Freire (2000) e (2001), Bourdieu (1992), McLaren (1992), os trabalhos de Haddad (2000), Kuenzer (1997), Frigotto (2005), Ciavatta (2008), de Oliveira (2003), de Andriola (2003), Almeida (2008), Marconatto (2009) entre outros. Obteve-se pela tÃcnica da anÃlise de conteÃdo, um total de 580 recortes das falas dos participantes, destacando-se 188 (32,41%) para as questÃes relacionadas à prÃtica pedagÃgica, 163 (28,10%) relacionados à evasÃo, 161 (27,76%) relacionados à permanÃncia e 68 (11,72%) relacionados à infraestrutura. Na anÃlise do conjunto de recortes, do perfil dos alunos e das observaÃÃes realizadas, constatou-se que os âfatores internosâ relacionados à instituiÃÃo tiveram uma prevalÃncia bastante acentuada no aumento da evasÃo naquele campus. / ABSTRACT In this work, we aimed at identifying the stronger factors that contributed to the dropping out of high school integrated to the professional education. The analyzed sample group belongs to the EJA modality at Federal Institute of Cearà (IFCE) â Fortaleza Campus. In order to improve the probabilities of finding more reliable and consistent answers, we worked with all involved segments in the pedagogical process: current ones and students that drop out, teachers, administrative staff and the pedagogue. This research was defined as an empirical case study with descriptive and explanatory features. Moreover, we intended to analyze: a) the composition of the curriculum, b) the dynamic of the relationship between teacher and student, c) the infrastructure conditions of the IFCE regarding the good performance of the course, and d) the more relevant issues which motivate the student to abandon the course. The methodological process of investigation, composed of three phases, occurred sequentially from 2009 to 2011. Summarily, these phases were: bibliographic, documental, and field researches, helped by techniques of focus group; participative observations; and semi-structured surveys along the investigated segments. With the purpose of founding our possible findings, we made a review about the history of the EJA and of the professional education in Brazil. Additionally, we defined the IFCEâs aspects, its PROEJA system, and, particularly, its students. Considered as theorical, work of Makarenko (1987), Freire (2000) and (2001), Bourdieu (1992), McLaren (1992), the work of Haddad (2000), Kuenzer (1997), Frigotto (2005), Ciavatta (2008), Oliveira (2003), of Andriola (2003), Almeida (2008) and Marconatto (2009), among others. From content analysis, we obtained speech samples of participants, distinguishing 188 (32.41%) for questions related to pedagogical practice, 163 (28.10%) related to dropping out, 161 (27.76%) related to permanence and 68 (11.72%) related to infrastructure. Based on the speech samples, studentsâ profile, and overall observations, it was found that the "internal factors" from the institution had a high contribution to dropping out of that campus.

This work deals with the qualitative requirements on services in IP networks based on technology Ethernet. We describe basic methods for imposing quality control mechanisms on services within networks. We elaborate on the ways, in which packets can be handled, overload controlled and transfer speed in network elements limited. Attention is given also to the Network Layer and Link Layer. Based on concrete specifications of network devices in UTKO laboratory an experimental network was designed and constructed. Network consisting of routers and switches linked several servers with client stations. Various types of data transfers (VoIP, HTTP, FTP, video) were generated. Several techniques for handling packets with different priorities were verified and compared. We observed that, in situations when connections are under full load, implementation of QoS support in the network becomes very important. This observation was confirmed by measurements. We also measured the parameters of the system during simulations of various situations, such as overload of a connection due to unsolicited operations or failure of a connection between routers. In order to guarantee the quality of services it is necessary to create a domain, in which rules are consistently observed in all network elements.

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No / This paper proposes a novel call admission control (CAC) algorithm and develops a two-dimensional markov chain processes (MCP) analytical model to evaluate its performance for heterogeneous wireless network. Within the context of this paper, a hybrid UMTS-WLAN network is investigated. The designed threshold-based CAC algorithm is launched basing on the user’s classification and channel allocation policy. In this approach, channels are assigned dynamically in accordance with user class differentiation. The two-dimensional MCP mathematical analytic method reflects the system performance by appraising the dropping likelihood of handover traffics. The results show that the new CAC algorithm increases the admission probability of handover traffics, while guarantees the system quality of service (QoS) requirement.

A sociedade atual está vivendo uma revolução baseada na informação. A recente explosão da popularidade da internet e desregulamentação dos setores públicos de telefonia em muitos países foram os principais responsáveis pelo aumento da demanda por largura de banda. Adicionalmente, houve um aumento no volume de tráfego em função do oferecimento de serviços multimídia de banda larga. Este cresimento rápido e global por demanda de largura de banda está acelerando o desenvolvimento e a implantação de redes de comunicações ópticas empregnando sistemas multiplexados em comprimento de onda (WDM). O emprego de fibras na transmissão de informações em alta velocidade a grandes distâncias já está consolidado, e sua utilização em redes metropolitanas MAN (Metropolitan Area Network) e redes de acesso está aumentando. Verifica-se que a tendência de evolução das redes ópticas é a aproximação das fibras até o usuário final. A forma mais viável economicamente de aproximar o usuário dos benefícios das redes ópticas com grande capacidade é o emprego de redes ópticas passivas PON (Passive Optical Network) empregando o sistema WDM. Este tipo de rede apresenta a flexibilidade de suportar tanto broadcast, onde o mesmo sinal é distribuído a todos os usuários, como serviços ponto-a-ponto. Um dos requisitos mais importantes para o aumento da capacidade destes sistemas ópticos é o aumento do número de canais (comprimentos de onda). Para viabilizar este aumento do número de canais é necessária a utilização de dispositivos com alta seletividade em comprimento de onda proposto neste trabalho. Este filtro é composto pela combinação de três estruturas distintas formando um único dispositivo: fibra tipo D, duplo refletor de Bragg (DBR), e guia multicamada em configuração ARROW ( Antiresonant Reflecting Optical Waveguide). O DBR é previamente definido na fibra tipo D e esta é então colada sobre a estrutura multicamada. ) A estrutura multicamada, por sua vez, possui a configuração ARROW em virtude de suas características de seletividade em comprimento de onda. A utilização de um fibra tipo D no dispositivo proposto permite que as perdas de inserção deste dispositivo no enlace óptico sejam drasticamente reduzidas. Este trabalho realiza um projeto criterioso de um filtro em questão, buscando valores ótimos para cada um dos parâmetros que compõem este dispositivo, tais como: espessuras de camadas, índices de refração, perda de inserção, isolação entre canais, etc. Os resultados obtidos com as simulações são discutidos e uma configuração ótima para o dispositivo é proposta. / The progress in lightwave propagation based on optical fibers has provided our society with an unprecedented communication capability. The deregulation of public telephone companies together with the increasingly popularity of the internet can be pointed out as the major contributors for this huge bandwidth demand we experience today. Additionally, there was a corresponding growth in traffic volume due to wideband multimedia services. As a consequence of this fast growing demand for bandwidth in a global scale, telecom companies have accelerated the development and implementation of optical communication networks based on wavelength division multiplexing (WDM) technology. The tendency in terms of network evolution is to approximate the optical fibers as close as possible to the end user. The most economically viable way of doing so is by way of the so called Passive Optical Networks (PON) based on WDM systems. This type of network is flexible enough to support broadcast, where the same signal is distributed to all users, and point-to-point services. If more capacity is required for these systems, this can be achieved just by adding new channels (wavelengths) to it. Another important issue regarding WDM systems consists in the extraction of channels from the optical network, which can be achieved by using highly selective dropping filters such as the one proposed in this work. This filter is defined by the combination of three distinct structures defining one single device: a d-type fiber, a double Bragg reflector (DBR), and a multilayer ARROW type waveguide (Antiresonant Reflecting Optical Waveguide). The DBR is defined beforehand on the d-fiber, and then the d-fiber is literally glued on top of the multilayer waveguide. This multilayer waveguide is fabricated directly atop of a p-i-n photodetector in such a way that the three structures (d-fiber, multilayer waveguide and photodetector) now form a rigid structure. The ARROW type configuration for the multilayer waveguide and the DBR structure are chosen by virtue of their wavelength selectivity characteristics, helping to improve the device performance. The d-fiber structure, by its tum, has the great advantage of reducing drastically the insertion loss when compared to rectangular waveguide filters. In the analysis provided in this work parameters such as layer thicknesses, refractive indices, insertion loss, channel isolation, etc, and their influence on the device performance, are extensively investigated for optimization purposes. The simulated results are discussed thoroughly and an optimal structure configuration is proposed.

Wildlife management deals with problems concerning sustainable harvest, conservation of threatened species and adjustment of wildlife populations to levels acceptable to for instance forestry, agriculture, traffic and conservation interests. A detailed knowledge of the population is then required. It is therefore important to develop reliable and cost-efficient survey methods. The purpose of this study was to test the distance sampling method where objects are observed while walking along a line, as a way of counting deer pellet groups and to compare the results with ordinary plot surveys. The inventory speed for distance sampling increases with increasing amount of droppings/km2. The amount of droppings seems to have little or no effect on the inventory speed of the plot survey method. Therefore the plot survey method could be a better alternative than the distance sampling method when the densities of droppings are high and vice versa. When comparing the two methods estimates of animal densities with data (orally) from game managers based on other surveys and flying observations and estimations in the different areas, both methods showed too low density for red deer in Valinge. This indicates that the supplementary feeding seem to have an effect on the results of red deer density for both methods.

Over the past few years, manufacturing companies have had to deal with an increasing demand for feature-rich products at low costs. The pressures exerted on their existing manufacturing processes have lead manufacturers to investigate internet-based solutions, in order to cope with growing competition. Today, the availability of powerful and low cost 3D tools, along with web-based technologies, provides interesting opportunities to the manufacturing community, with solutions directly implementable at the core of their businesses and organizations. The wooden sign is custom i.e. each sign is completely different from each other. Mass Customization is a paradigm that produces custom products in masses. A wooden sign is custom in nature, and each sign must be completely different from another. Although process planning for mass customized products is same, the tool path required to CNC machine the custom feature varies from part to part. If the tool path is created manually the economics of mass production are challenged. The only viable option is to generate the tool path automatically; furthermore, any time savings in the tool path lead to better profit margins. This thesis presents the automatic web-based tool path planning method for machining sculptured wooden sign on 3 axis Computer Numerical Controlling (CNC) Machines using optimal and cost-effective milling cutters. The web-based tool path planning strategy is integrate with web-based CAD system to automatically generate tool paths for the CAD model using optimal cutter within desired tolerances. The tool path planning method is divided into two parts: foot print (path along which cutter moves) and cutter positioning. The tool path foot print is developed during design stage from the CAD model based on the type of surface to be machined. The foot print varies from part to part which facilitates the mass customization of wooden sign. After designing foot print, the foot print is discretized into points and the gouge-free cutter position at each of these points is found using "Dropping Method". The Dropping Method where cutter is dropped over the work piece surface, and the highest depth at which cutter can go without gouging the surface is calculated. This is repeated for all the position along the foot print. This tool path planning strategy is developed for ball nose, flat-end and radiused end milling cutter for machining wooden sign. The tool path generated using this method is optimized for machining time, tool path generation time and final surface finish. The bucketing technique is developed to optimize tool path generation time, by isolating the triangles which has possibility of intersection at particular position. The bucketing Technique reduced the tool path computation by 75 %, and made tool path generation faster. The optimal cutter selection algorithm is developed which selects best cutter for machining the surface based on the scallop height and volume removal results. The radiused end milling cutter results in highest volume removal which results in lower machining time compared to ball nose end milling cutters, but the scallop heights is higher. However, the scallop height in the radiused end milling cutter is higher only in few regions which reduces the final surface finish. For a sign, it was found around the boundary of logo, outline of lettering, interface of border and background. Thus, in order to achieve higher surface finish and lower machining time, a separate tool path is developed using "Pencil Milling Technique" which will remove the scallops from the regions that was inaccessible by radiused end mills. This tool path with the smaller cutter will move around the boundary of logo and lettering, and clean-up all the scallops left on the surface. The designed tool path for all the three cutters were tested on maple wood and verified against the actual Computer Aided Design model for scallop height and surface finish. The numerical testing of tool path was carried out on a Custom Simulator, ToolSim and was later confirmed by actually machining on a 3 axis CNC machine. The same sign was machined with variety of milling cutters and the best cutter was selected based on the minimum scallop and maximum volume removal. The results of the experimental verification show the method to be accurate for machining sculptured sign. The average scallop height in a machined using 1/8 th inch radiused end milling cuter and using Pencil tool path on the machined surface is found to be 0.03989 mm (1.5708 thou).