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With the increase in the number of Internet users, due to digital inclusion, it is necessary to find the best possible way to provide this service. Among all forms of data transmission, PLC (Power Line Communication) is the one that has stood out the most in recent years, mainly due to its infrastructure, which allows users in semi-urban or even rural regions, and by the fact of ensuring high speed rates (up to 200 Mbps), through the broadband PLC, the BPL (Broadband Power Line), which uses the HomePlug AV standard. However, because the infrastructure used is the power lines, PLC is subject to numerous problems, such as interference, noise and attenuation. Therefore, there is a need to evaluate the performance of this broadband technology with regard to its use in domestic environments, analyzing its effectiveness amidst electrical interference. This paper presents an analysis of the performance of a PLC network that uses the HomePlug AV standard, with the objective of evaluating its viability in a domestic environment, since it presents several challenges for this technology Esde

In this paper, we propose a novel hybrid strategy that combines mixed integer linear programming (MILP) formulation with different alternative routing approaches that is capable of solving, simultaneously, the routing, modulation format and spectrum assignment problem in the design of elastic optical networks. We extend our proposal to a path-link formulation that, although it is not guaranteed to find the optimal solution, it has shown reasonable solutions within inferior simulation time, allowing it to be used in not very short networks. We also compare our proposal with another MILP formulation and three adapted heuristics, all available in the literature. The results show the benefits of our proposal considering diverse simulation scenarios and different number of modulation formats over 19 realistic networks in terms of simulation run time and maximum number of used set of slots.

In spectrum-sliced elastic optical path networks (SLICE), the lightpath bandwidth is variable, and the virtual topology overlay on a physical topology shall be designed to optimize the spectrum utilization. Under static traffic, SLICE networks are typically designed through a mixed integer linear programming (MILP) with the aim of minimizing the spectrum utilization. In this paper, a new MILP formulation for protection in SLICE networks is proposed, which uses the concept of bandwidth squeezing and grooming to guarantee a minimum agreed bandwidth for each source-destination pair in the surviving bandwidth. The route for each demand on the physical topology is determined by balance equations together with physical layer constraints in the formulation, so that no pre-calculated routes are required and the modulation format of each established lightpath may be chosen with enough quality of transmission and to save network spectrum. Therefore, the proposed formulation jointly solves the virtual topology design and physical topology design problems. The first results evaluate the effectiveness of the MILP formulation for two small networks when connections are under different service-level agreement (SLA) requirements and are provisioned by an appropriate protection scheme and different modulation formats. Due to the NP-hard nature of the proposed MILP formulation, a heuristic algorithm for moderately large networks is also proposed. Case studies are carried out to analyze the basic properties of the formulation and the performance of the proposed heuristic. With the proposed formulation, it is possible to identify the configurations that ensure minimum spectrum occupation with different kinds of protection for each lightpath. Different kinds of modulation formats are considered and contrasted to the benchmark case of a single modulation format and using the same kind of protection for all lightpaths.

An elastic optical network (EON) plays an important role in transport technology for virtualization of networks. A key aspect of EONs is to establish lightpaths (virtual links) with exactly the amount of spectrum that is needed and with the possibility of grooming, the process of grouping many small traffic flows into larger units, creating a super-lightpath. Grooming eliminates the need for many guard bands between lightpaths and also saves transceivers; however, it often leads to the need to perform optical–electrical–optical conversions to multiple-data-rate optical signals at intermediate nodes. The aim of this paper is to provide a mixed-integer linear programming (MILP) formulation, as well as heuristic and meta-heuristic approaches, for the design of multiple virtual optical networks (VONs) in an elastic optical substrate network with bandwidth-variable lightpaths, modulation format constraints, and virtual elastic regenerator placement. Traffic grooming is allowed inside each VON, and a distance-adaptive modulation format technique is employed to guarantee efficiency in terms of bandwidth for a physical substrate, subject to several virtual topologies. A reduced MILP formulation without grooming capability is also proposed for comparison. The complete MILP formulation jointly solves the virtual topology design, regenerator placement, and grooming problems, as well as the routing, modulation, and spectrum assignment (RMSA) problem. The reduced MILP formulation, heuristics, and meta-heuristic, on the other hand, separate the virtual topology design problem from the RMSA problem. It is shown that the grooming approach can provide good results, since it solves the problem for a complete design when compared to the approach without grooming. Furthermore, heuristic solutions for large networks are proposed, which present good performance (in terms of saving spectrum) for the design with large instances.

In Spectrum-sliced Elastic Optical (SLICE) networks, based on Orthogonal Frequency Division Multiplexing (OFDM), several signals can be sent into the same fiber optical link, each signal modulated by tightly packed orthogonal sub-carriers that can be adjacently allocated to satisfy different bandwidth requirements. The bandwidth allocation in such fine-granularity OFDM-based optical network is more efficient than in networks based on Wavelength Division Multiplexing (WDM), but with an increased complexity. Such problem is known as the Routing and Spectrum Assignment (RSA). In this paper, we propose a RSA heuristic algorithm to minimize the maximum load and balance the traffic load on the network, while minimizing the number of hops in the established lightpaths. The proposed algorithm is compared to the shortest path allocation algorithm for incremental traffic simulations. The results show that the proposed heuristic algorithm can minimize the maximum load on the network, balance the traffic between the links, and save resources for future requests. Furthermore, the analysis of the blocking characteristics shows that the proposed heuristic can postpone traffic blocking, although the effectiveness can vary depending on the network topology and also on the maximum amount of available sub-carriers.

In Elastic Optical Networks (EON), the problem of routing and spectrum Allocation (RSA) has been solved along the years through the use of optimization techniques or heuristics, with the aim of minimizing the use of network resources or maximizing the capacity for future requests. The effects of the physical layer in the RSA problem are of fundamental importance given that there is a distance limitation with the required bit rate and modulation format used to transmit the signal. On considering the linear and non-linear noise effects, it is possible to include quality of transmission (QoT) in the optimization process. In this paper, we propose a modification to a traditional heuristic for the RSA problem in Elastic Optical networks to consider both effects of the physical layer. The proposed modification takes into account the channel input power and SNR Margin to choose all modulation formats and to assign resources. The main goal is to increase the spectral efficiency and throughput of the channels by mitigating blockages in the physical layer. Simulations were performed for various topologies, and the results suggest advantages in terms of number of blocked channels and spectrum usage of the new proposal in relation to the traditional BSR heuristics.

This work proposes a new Mixed Integer Linear Programming (MILP) formulation for traffic grooming, routing and spectrum allocation to be used in the design of Elastic Optical Networks (EON). In order to compare our method with classic Routing and Spectrum Allocation (RSA) formulation without grooming, the evaluation of the benefits of exact traffic grooming and RSA formulation are presented over three small networks. For each network, the objective function is set as minimizing the maximum slot index among all fibers. Then, the collected results show the benefits of traffic grooming in EON networks. Due to the NP characteristic of the MILP proposed, we propose a heuristic algorithm for large networks, and the benefits of the grooming using this algorithm are investigated.

Ha registro na literatura que aponta deficiencias em sistemas computacionais de gerenciamento de clinicas odontologicas, quanto aos criterios de funcionalidade, seguranca e interface. Tais imitacoes prejudicam o profissional, pois a falta de uma documentacao completa o deixa exposto a possiveis penalidades em embates judiciais. A falta de seguranca expoe o documento ao acesso e manipulacao por pessoas nao autorizadas, e a interface deficiente torna o software dificil de utilizar. Neste artigo, e apresentado um software de gestao de clinica odontologica que alem de cumprir com todos os requisitos quanto aos criterios de seguranca, funcionalidade e interface, utiliza o recurso da filmagem como parte integrante do prontuario odontologico. Inicialmente foram levantados e modelados os requisitos do sistema, e apos este processo foi desenvolvida a primeira versao contando com os modulos de Gerenciamento de Pacientes, Funcionarios e Usuarios, Agenda, Plano de Tratamento, Odontograma e Registro de Filmagem da Consulta. O software produzido atendeu aos requisitos de gestao de uma clinica odontologica, alem de integrar a filmagem legal ao prontuario odontologico. O software desenvolvido cumpriu os requisitos de funcionalidade, seguranca e interface, e apresentou melhorias em relacao aos demais softwares existentes no mercado considerando os requisitos avaliados.

The objective of this article was to investigate the perception of esthetic changes in the facial profile of bilateral Class II patients treated with the Modified Thurow Appliance for extraoral treatment. Silhouettes were traced of profiles of patients who initially presented a bilateral Class II molar relationship and who, post-treatment, presented molars in a Class I relationship. Three groups were formed: the first composed of patients with maxillary protrusion (SNA >84°), the second with maxillary retrusion (SNA

Spectrum-sliced elastic optical path networks (SLICE) enable flexible bandwidth provisioning, which allows efficient resource utilization and support to heterogeneous bandwidth demands. This makes SLICE a very promising networking architecture. In SLICE, finding a route and a slice of the spectrum is an important design problem, which is known as the Routing and Spectrum Assignment (RSA) problem. In this paper, we present a new heuristic, based on Yen's k-shortest path algorithm and capable of dealing with the traffic heterogeneity to find appropriate sets of paths for each source-destination node pairs to mitigate the bottleneck in the network. The results show that the proposed algorithm reduces the lightpath blocking probability and achieves significantly improved spectrum efficiency. We also analyse the maximum number of alternate shortest paths for minimising the blocking probability.

This paper proposes heuristics, which can maximize the number of remaining available routes and minimize the number of transceivers used in Elastic Optical Networks (EON). The aim of the proposal is to preserve the open capacity for the accommodation of future unknown dynamic demands. Case studies are carried out in order to analyze the performance of the heuristics over two networks. The results suggest that it is feasible to preserve enough open capacity to avoid blocking of future requests in EON with scarce resources.

The business world has been in constant competition and information is the main tool for the decision process in order to obtain more clients, to improve the performance, the quality of services and to increase profits. Facing this reality, Information Technology (IT) has been improving technologies and making possible many advances in this area. Objective: This article aims to perform a technical analysis about softwares designed for dental practice management by assessing their available functions. Material and methods: Softwares were assessed in the period from July to October of 2011 by using the following criteria: functions, interface, security and price. Results: The software had neither all fundamental items nor all the security items assessed. 75% responded positively to at least half of the interface heuristics proposed by Nielsen. Price is around R$ 576.96 per year and 40% of the softwares have purchase rate from R$ 50.00 to R$ 100.00. Conclusion: The research and analysis found out that most of softwares show some problems about security and functions. However, they exhibited user-friendly interface and affordable prices.

Objective: To evaluate the degree of perception of laypersons, professionals, and dental students, regarding the aesthetic appearance of the smile in cases of gingival plastic surgery of the maxilla for correction of a gingival smile, by examining alterations in photographs. Materials/Methods: Alterations were made to an extraoral front-view-photograph of a gingival smile in normal occlusion, by gingival recontouring of the maxilla, simulating a gingival plastic surgery procedure to diminish gingival exposure. For this purpose, specific image-manipulation program (Adobe-Photoshop-Software-CS3) was used. Images were printed on photographic-paper, attached to questionnaire, distributed among laypersons, professionals, and dental students to evaluate degree of aesthetics ( n = 150). To evaluate degree of aesthetics, an attractiveness scale was used, with 0 representing hardly attractive, 5 for attractive, and 10 for very attractive. Differences between examiners were examined by Mann–Whitney test. All the statistics were performed with a confidence level of 95 per cent. Results: Both dental professionals and students and laypersons were capable of identifying alterations resulting from gingival plastic surgery. In all evaluated groups, they demonstrated that large gingival extension does not always affect aesthetic appearance of the smile, and maxillary incisors not being much visualized is characterized as hardly attractive, with statistically lower scores being attributed ( P < 0.05). Conclusions: According to aesthetic parameters, the presence of the gingiva is important in the composition of the smile, however, only when exposed to small extent.

With network virtualization, the physical infrastructure can be partitioned into multiple parallel virtual networks for sharing purpose. However, different transport technologies or Quality of Service (QoS) levels may impact in both the requested amount of resources and the characteristics of different virtual instances that can be built on top of a single physical infrastructure. In this paper we propose a novel Mixed Integer Linear Programming (MILP) formulation for different schemes of protection in scenarios where multiple virtual topologies run over an elastic optical network. The proposed MILP formulation uses the concept of bandwidth squeezing to guarantee a minimum bandwidth for surviving virtual topologies. It achieves a high level of survivability for the traffic that is subject to a different committed service profile for each virtual topology. Case studies are carried out in order to analyse the basic properties of the formulation in small networks, and three heuristics are proposed for larger networks.

Neste trabalho propomos e analisamos algoritmos de alocação dinâmica de banda para rede óptica passiva (PON) de acesso padrão GPON (Gigabit PON). Estes algoritmos utilizam dados oriundos de SLA (service level agreement) para gerenciar a alocação de banda e classificar em 4 contêineres de tráfego (T-CONT) o tráfego gerado em 16 ONUs (optical network unit). Na transmissão upstream é utilizada a técnica de multiplexação por divisão de tempo (TDM) para gerenciar o acesso ao meio, evitando colisões. O primeiro algoritmo proposto aloca banda garantida para as ONUs e distribui a banda não utilizada de acordo com critério baseado em três SLAs. A taxa de bit upstream é 1,25 Gbps e o desempenho do algoritmo é analisado com base na variação do atraso de pacotes em função do tráfego gerado nas ONUs. O segundo algoritmo proposto utiliza ponderação de tráfego. Neste, analisamos o comportamento dos atrasos e a quantidade de banda solicitada e atendida por ONU quando as bandas garantida e extra são alteradas. Por fim, acrescentamos em nossa implementação um intervalo para o processamento do algoritmo de alocação dinâmica de banda (DBA) e resposta do hardware relacionado ao ciclo de interrogação. Então, analisamos o atraso de pacotes quando variamos o intervalo de processamento do DBA. Ao final, propomos uma solução preliminar para minimizar estes atrasos. Os resultados obtidos por meio de simulação computacional mostram a versatilidade dos algoritmos. In this work we propose and analyze the performance of dynamic bandwidth allocation algorithms for optical passive networks (PON) in GPON standard (Gigabit PON). These algorithms use data from SLA (service level agreement) to manage bandwidth allocation and classify in 4 traffic containers (T-CONT) the traffic generated by 16 ONUs (optical network unit). In the upstream transmission the time division multiplexing (TDM) technique is used to manage the medium access, avoiding collisions. The first proposed algorithm allocates guaranteed bandwidth for the ONUs and distributes the bandwidth not used according to the criteria based on three SLAs. The upstream bit rate is 1.25 Gbps and the algorithm performance is analyzed based on the packets delay variation versus the traffic generated by ONUs. The second proposed algorithm uses weighted traffic. In this, we analyze the delay performance and the required bandwidth for each ONU and how much it is served when the guaranteed and extra bandwidth are changed. Finally, we added in our implementation an interval for the processing of the dynamic bandwidth allocation algorithm (DBA) and response of the hardware related to the interrogation cycle. In the end, we propose a preliminary solution to minimize these delays. The results obtained by means of computational simulation show the versatility of the algorithms.

Introducao: A educacao nao precisa se limitar ao discurso de um professor em sala de aula. Existem formas de tornar o aprendizado mais facil e eficaz, e umas das principais e a linguagem audiovisual. Atraves dela, a informacao ganha um formato mais simples de se digerir e lembrar. Uma vertente importante do audiovisual e a animacao, que tem um apelo especialmente forte com o publico infantil. Pode-se aproveitar essa empatia que a animacao tem com as criancas para capturar a tao voluvel atencao delas. Objetivos: Expor o valor da animacao como forma de simplificar o aprendizado e apresentar uma animacao desenvolvida pelo Nucleo de Extensao e Pesquisa Odontologica (NEPO) em parceria com o Centro de Pesquisa e Desenvolvimento de Software (CPDS) com intuito de mostrar a importância da escovacao diaria. Materiais e metodos: Para a pesquisa, foram analisadas obras disponiveis na Biblioteca Jorge Amado, localizada no campus de Jequie da Universidade Estadual do Sudoeste da Bahia, nas bases de dados do Scielo e do Google Academico, nas bibliotecas virtuais da USP e da Unicamp. Para o desenvolvimento da animacao foram utilizados Softwares especificos da area de informatica voltados para animacao de imagens. Resultados: A pesquisa nos levou a diversos documentos relacionados ao uso da animacao ou do audiovisual em geral na educacao. Com base nestes estudos, criamos um video animado mostrando a importância da animacao no cotidiano das pessoas. Conclusao: A pesquisa mostrou a importância de encontrar formas diferentes de realizar o ensino.

The performance improvement imparted by routing and spectrum assignment on flexible grid optical networks is a subject of current extensive investigation. Proposed is an efficient spectrum-assignment algorithm based on reducing the loss of capacity of future bandwidth-variable path requests. In all scenarios analysed the proposed algorithm outperformed currently investigated slot assignment algorithms.

Current communication in optical networks presents a wide range of granularities, making it hard to use the optical spectrum efficiently under the WDM framework. In Spectrum Sliced Optical Networks, the WDM rigid frequency grid is replaced by a more flexible structure, in which the spectrum is organized in frequency slots, and each traffic flow is assigned to an appropriate set of contiguous slots. The classical Routing and Wavelength Assignment (RWA) problem is then replaced by a Routing and Spectrum assignment (RSA) problem. This paper addresses an iterativa approach to balance the network load during the routing decision in Spectrum-Elastic Optical Path Networks. We have built numerical examples to illustrate the performance of our routing approach. Comparisons to other routing techniques show that our approach mitigates the lightpath requests blocking probability.

This paper proposes a novel joint resource allocation technique for flexible-grid systems by utilizing non-dominant sort genetic algorithm (NSGA-II) in a multi-objective optimization framework. It pioneers the implementation of an evolutionary mechanism to optimize resources as means of mitigation of physical layer impairments. This investigation initially introduces a proposal in which bandwidth reduction, maximization of the minimum signal-to-noise ratio (SNR) margin, and minimization/maximization of the sum of SNR margins are studied under dual-objective Pareto analysis in the link-level scenario. Later, the technique extends existing provisioning strategies for network planning by targeting the reduction of blocking and spectral utilization of optical connections.