Uma arquitetura baseada em SCTP e SIP para suporte a aplicações VoIP móveis e a especificação formal do seu módulo de controle

New versions of SCTP protocol allow the implementation of handover procedures in the transport layer, as well as the supply of a partially reliable communication service. A communication architecture is proposed herein, integrating SCTP with the session initiation protocol, SIP, besides additional protocols. This architecture is intended to handle voice applications over IP networks with mobility requirements. User localization procedures are specified in the application layer as well, using SIP, as an alternative mean to the mechanisms used by traditional protocols, that support mobility in the network layer. The SDL formal specification language is used to specify the operation of a control module, which coordinates the operation of the system component protocols. This formal specification is intended to prevent ambiguities and inconsistencies in the definition of this module, assisting in the correct implementation of the elements of this architecture

Controlador adaptativo por posicionamento de pólos e estrutura variável aplicado ao controle de geradores eólicos baseados em máquina de indução duplamente alimentada

In the last decade, the renewable energy sources have present a major propulsion in the world due to several factors: political, environmental, financial and others. Within this context, we have in particular the energy obtained through wind, wind energy - that has highlighted with rapid growth in recent years, including in Brazil, mostly in the Northeast, due to it s benefit-cost between the clean energies. In this context, we propose to compare the variable structure adaptive pole placement control (VS-APPC) with a traditional control technique proportional integral controller (PI), applied to set the control of machine side in a conversion system using a wind generator based on Double-Fed Induction Generator (DFIG). Robustness and performance tests were carried out to the uncertainties of the internal parameters of the machine and variations of speed reference.

Percolação convencional, percolação correlacionada e percolação por invasão num suporte multifractal

In this work we have studied the problem of percolation in a multifractal geometric support, in its different versions, and we have analysed the conection between this problem and the standard percolation and also the connection with the critical phenomena formalism. The projection of the multifractal structure into the subjacent regular lattice allows to map the problem of random percolation in the multifractal lattice into the problem of correlated percolation in the regular lattice. Also we have investigated the critical behavior of the invasion percolation model in this type of environment. We have discussed get the finite size effects

Efeitos do treino em esteira com suporte parcial de peso e do método de facilitação neuromuscular proprioceptiva na marcha hemiparética: estudo comparativo

Objective: To compare the effects of the treadmill training with partial body-weight support (TPBWS) and Proprioceptive Neuromuscular Facilitation (PNF) method on gait of subjects with chronic stroke. Design: Quasi-experimental study. Setting: Laboratorial research. Participants: Twenty-three subjects (13 men and 10 women), with a mean age of 56,7 ± 8,0 years and a mean time since the onset of the stroke of 27,7 ± 20,3 months, and able to walk with personal assistance or assistive devices. Interventions: Two experimental groups underwent gait training based on PNF method (PNF group, n=11) or using the TPBWS - Gait Trainer System 2, Biodex, USA (TPBWS group, n=12), for three weekly sessions, during four weeks. Measures: Evaluation of motor function - using the Stroke Rehabilitation Assessment of Movement (STREAM) and the motor subscale of the Functional Independence Measure (motor FIM) -, and kinematic gait analyze with the Qualisys System (Qualisys Medical AB, Gothenburg, Sweden) were carried out before and after the interventions. Results: Increases in the STREAM scores (F=49.189, P<0.001) and in motor FIM scores (F=7.093, P=0.016), as well as improvement in symmetry ratio (F=7.729, P=0.012) were observed for both groups. Speed, stride length and double-support time showed no change after training. Differences between groups were observed only for the maximum ankle dorsiflexion over the swing phase (F=6.046, P=0.024), which showed an increase for the PNF group. Other angular parameters remain unchanged. Conclusion: Improvement in motor function and in gait symmetry was observed for both groups, suggesting similarity of interventions. The cost-effectiveness of each treatment should be considered for your choice

Os Centros de Especialidades Odontológicas como suporte da atenção básica: uma avaliação na perspectiva da integralidade

The public dental services in Brazil were limited, practically, to the basic care, so that the specialized services acted, up to 2002, no more than 3,5% of the total of clinical procedures. That lower offer reveals the difficulty of continuity of the attention, that is, the comprehensiveness in the assistance, particulary, the reference and counter-reference system. Brasil Sorridente search to supply those needs when proposing Speciality Dental's Centers(CEOs Centros de Especialidades Odontológicas, Brazil) to compose the services of average complexity. In 2005, Ministry of Health enabled the three CEOs of Natal, located in the North II, East and West Sanitary Districts. This investigation evaluated the implantation of these CEOs, as support of the family health care teams, in the perspective of organization of the services in assistencial nets in Natal/RN. It was a study of evaluation, with qualitative approach and some quantitative data as contribution. Dentists, users and managers were interviewed to identify and to understand their perceptions, relationships and experiences in the daily of the services. The conceptual base that orientated the investigation was the principle of comprehensiveness, in its operational sense of the hierarchization in health attention levels. The collection of data was done with documental research, direct observation and semi-structured interview. The analysis was accomplished by triangulation of the extracted content from the used techniques and sources of interviewed groups depositions, looking for theoretical-conceptual support in specific bibliography. The results pointed aspects that go away from the comprehensiveness like: low resolution of problems in the basic net; little valorization of the space in the health units; traditional models of access to health services, insufficient offer for some specialties, compromising the reference and counter-reference system; practices centered in procedures in the CEO; bureaucratic directions from basic care to the specialized service; disintegrated and disjointed system among levels of attention; disrespect to the municipal protocol. On the other hand, there is an approach of compreensiveness in situations like: increase of the access and covering in the Family Health Strategy (ESF Estratégia Saúde da Família, Brazil); larger approach between professional and user; tendency to the quantitative and qualitative growth of specialized actions; punctual initiatives of relationships among levels; existence of protocol to guide professionals

Adolescentes e jovens e suas bases de apoio :relações de amizade como suporte social no enfrentamento à violência

The purpose of this work is to map the family and community social supports for adolescents and young students from Bom Pastor Distric, West Zone of Natal/RN, as well as to describe how such resources are used by these individuaIs in that community. Social support refers not only to formal activities or organizations, but also to spontaneous or informal forms of support - friendship and solidarity nets available in the community, affective relations that are meaningful in the lives of children and young people. Our discussion is based on a research performed with 382 adolescents and young students from Jean Mermoz Public School (students from 5th to 11th grades, aged 13 to 14). We emphasized the situations of violence derived from family or community spheres faced by these students. In relation to this specific aspect, we observed the participants more frequently look for help from the informal social supports, mostly from their friends, which indicates that the formal ones are not considered to be effective instruments for social assistance. The search for informal social supports shows the relations informally established in the streets (for instance when they look for help from friends, rei atives or neighbors) have more effect and play an important role in which there are values and affections exchange. Thinking the strengthening of these social links is of extreme importance and leads to the weakening of the hegemonic logics focused on the production of subjects as private identities, and to the amplification of an ethics committed to the disassembly of a sociability anchored to fear, impotence, intolerance, discrimination, and reduction of spaces for circulating and confronting mechanisms of social exclusion. It is crucial that we concentrate our attention to building friendship as a system of reciprocity and affective exchanges, as a space for political actions and production of forms of lives that are potent against social anesthesia

Suporte ao uso de álcool e drogas na atenção primária: um estudo com equipes de Natal/RN

National surveys indicate that 6.8 % of the brazilian population is dependent on alcohol and 1 % dependent on illicit drugs, representing a significant portion of the population affected by this issue . Primary Care becomes instrumental in expanding the coverage of this demand and in reducing unnecessary referrals for specialized care. This study aimed to investigate the responsiveness and institutional support of Primary Care Teams in relation to the demands of alcohol and drugs users. The research was conducted in a Family Health Unit in West Sanitary District of Natal City. With quantitative and qualitative nature, our study consisted of two stages. At first, we performed a mapping of alcohol and other drugs abusive use in a sample of the population assisted by Family Heath Teams, using sociodemographic questionnaire and ASSIST (Alcohol, Smoking and Substance Involvement Screening Test). 406 questionnaires were completed. Of these questionnaires, 27.8% are men and 72.2% women, of which 56% are between 20 and 39 years-old, they are housewives, have a stable relationship and are consumers of tobacco (37.6%), marijuana (13%) and especially alcohol (57%). In second stage, two Conversation Circles with Family Health Teams and the referential Family Health Support Center were formed to discuss the data of the mapping realized in the previous phase. The circles, which had participation of 20 of the 37 professional teams from Family Health and 2 from Family Health Support Center, showed a lack of professional training in the subject; inability of the healthcare network in the user embracement; belief of professionals that nothing can be done when matter is alcohol and drugs; and referencing as the only care action performed by teams. Thus we point out the need to support an approach on issues of alcohol and drugs which consider gender issues, investing in Harm Reduction Policy as a possibility of working in this context for recognizing each user in their uniqueness and strategizing with them to promote health in a broad and contextualized way

A percepção de suporte organizacional dos novos servidores da Universidade Federal do Rio Grande do Norte

This work deals with organizational support perception-OSP. This is done considering staff global beliefs, value of their contributions, care and well being related of individuals in an organization. These issues has been have been present in many researches since the 80s. It is important to analyze this matter considering all the changes that occurred nationally and internationally in the academic environment, characterized as being diversified in academic and managerial level. This occurs especially in Brazil since Federal Universities and their agents have suffered impact and restructuring. The research has emphasized the technical-managerial as well as professor staff level at Universidade Federal do Rio Grande do Norte aiming to deal with their unsatisfaction upon social political support. Thus, there was participation of 259 staff that were admitted from 2003 to 2005 in many sectors and units of the university. These subjects were submitted to a social and demographical query through an application of a scale of organizational support perception-OSP. Descriptive and multivariate analysis was done considering factors (management style of higher command), material support, wages, work overload, social support at work and ascending levels). Results show that there a hierarchy of the analyzed factors, the factor social support at work as being the first one with 3,31%, the factor management style of the higher command in second with 3,30%, then followed by the factor social support at work with 2,92%, in a sequence the factor material support, factor overload with 2,49% in the fourth position, and in the fifth place, the factor ascending with an average of 2,33% and in last the factor wages with 2,20%. It is concluded that the factors related to the more positive attributions of the OSP (social support at work), in a sequence material support opposing from the most negative factors of the OSP (wages, overload, ascending) reveal a reality that points out that the OSP is very much related to the individualized actions of the members of the organization (leader-member-group) rather than on structure and institutionalized actions carried out at UFRN

Reforma a vapor catalítica do metano: Otimização da produção e seletividade em hidrogênio por absorção in situ do CO2 produzido

Topics of research related to energy and environment have significantly grown in recent years, with the need of its own energy as hydrogen. More particularly, numerous researches have been focused on hydrogen as energy vector. The main portion of hydrogen is presently obtained by reforming of methane or light hydrocarbons (steam, oxy, dry or auto reforming). During the methane steam reforming process the formation of CO2 undesirable (the main contributor to the greenhouse effect) is observed. Thus, an oxide material (sorbent) can be used to capture the CO2 generated during the process and simultaneously shifting the equilibrium of water gas shift towards thermodynamically more favorable production of pure hydrogen. The aim of this study is to develop a material with dual function (catalyst/sorbent) in the reaction of steam reforming of methane. CaO is well known as CO2 sorbent due to its high efficiency in reactions of carbonation and easy regeneration through calcination. However the kinetic of carbonation decreases quickly with time and carbonation/calcination cycles. A calcium aluminate (Ca12Al14O33) should be used to avoid sintering and increase the stability of CaO sorbents for several cycles. Nickel, the industrial catalyst choice for steam reforming has been added to the support from different manners. These bi-functional materials (sorbent/catalyst) in different molar ratios CaO.Ca12Al14O33 (48:52, 65:35, 75:25, 90:10) were prepared by different synthesis methodologies, among them, especially the method of microwave assisted self-combustion. Synthesis, structure and catalytic performances of Ni- CaO.Ca12Al14O33 synthesized by the novel method (microwave assisted selfcombustion) proposed in this work has not being reported yet in literature. The results indicate that CO2 capture time depends both on the CaO excess and on operating conditions (eg., temperature and H2O/CH4 ratio). To be efficient for CO2 sorption, temperature of steam reforming needs to be lower than 700 °C. An optimized percentage corresponding to 75% of CaO and a ratio H2O/CH4 = 1 provides the most promising results since a smaller amount of water avoids competition between water and CO2 to form carbonate and hydroxide. If this competition is most effective (H2O/CH4 = 3) and would have a smaller amount of CaO available for absorption possibly due to the formation of Ca(OH)2. Therefore, the capture time was higher (16h) for the ratio H2O/CH4 = 1 than H2O/CH4 = 3 (7h) using as catalyst one prepared by impregnating the support obtained by microwave assisted self-combustion. Therefore, it was demonstrated that, with these catalysts, the CO2 sorption on CaO modifies the balance of the water gas-shift reaction. Consequently, steam reforming of CH4 is optimized, producing pure H2, complete conversion of methane and negligible concentration of CO2 and CO during the time of capture even at low temperature (650 °C). This validates the concept of the sorption of CO2 together with methane steam reforming

Estendendo CRefine para o suporte de táticas de refinamento

The use of increasingly complex software applications is demanding greater investment in the development of such systems to ensure applications with better quality. Therefore, new techniques are being used in Software Engineering, thus making the development process more effective. Among these new approaches, we highlight Formal Methods, which use formal languages that are strongly based on mathematics and have a well-defined semantics and syntax. One of these languages is Circus, which can be used to model concurrent systems. It was developed from the union of concepts from two other specification languages: Z, which specifies systems with complex data, and CSP, which is normally used to model concurrent systems. Circus has an associated refinement calculus, which can be used to develop software in a precise and stepwise fashion. Each step is justified by the application of a refinement law (possibly with the discharge of proof obligations). Sometimes, the same laws can be applied in the same manner in different developments or even in different parts of a single development. A strategy to optimize this calculus is to formalise these application as a refinement tactic, which can then be used as a single transformation rule. CRefine was developed to support the Circus refinement calculus. However, before the work presented here, it did not provide support for refinement tactics. The aim of this work is to provide tool support for refinement tactics. For that, we develop a new module in CRefine, which automates the process of defining and applying refinement tactics that are formalised in the tactic language ArcAngelC. Finally, we validate the extension by applying the new module in a case study, which used the refinement tactics in a refinement strategy for verification of SPARK Ada implementations of control systems. In this work, we apply our module in the first two phases of this strategy

Uma máquina de redução de grafos para serviços web

Web services are software accessible via the Internet that provide functionality to be used by applications. Today, it is natural to reuse third-party services to compose new services. This process of composition can occur in two styles, called orchestration and choreography. A choreography represents a collaboration between services which know their partners in the composition, to achieve the service s desired functionality. On the other hand, an orchestration have a central process (the orchestrator) that coordinates all application operations. Our work is placed in this latter context, by proposing an abstract model for running service orchestrations. For this purpose, a graph reduction machine will be defined for the implementation of service orchestrations specified in a variant of the PEWS composition language. Moreover, a prototype of this machine (in Java) is built as a proof of concept

Reengenharia do framework cosmos: uma solução para prover suporte e adaptações abertas.

Self-adaptive software system is able to change its structure and/or behavior at runtime due to changes in their requirements, environment or components. One way to archieve self-adaptation is the use a sequence of actions (known as adaptation plans) which are typically defined at design time. This is the approach adopted by Cosmos - a Framework to support the configuration and management of resources in distributed environments. In order to deal with the variability inherent of self-adaptive systems, such as, the appearance of new components that allow the establishment of configurations that were not envisioned at development time, this dissertation aims to give Cosmos the capability of generating adaptation plans of runtime. In this way, it was necessary to perform a reengineering of the Cosmos Framework in order to allow its integration with a mechanism for the dynamic generation of adaptation plans. In this context, our work has been focused on conducting a reengineering of Cosmos. Among the changes made to in the Cosmos, we can highlight: changes in the metamodel used to represent components and applications, which has been redefined based on an architectural description language. These changes were propagated to the implementation of a new Cosmos prototype, which was then used for developing a case study application for purpose of proof of concept. Another effort undertaken was to make Cosmos more attractive by integrating it with another platform, in the case of this dissertation, the OSGi platform, which is well-known and accepted by the industry

BTS:uma ferramenta de suporte ao desenvolvimento sistemático de sistemas confiáveis baseados em componentes

The component-based development of systems revolutionized the software development process, facilitating the maintenance, providing more confiability and reuse. Nevertheless, even with all the advantages of the development of components, their composition is an important concern. The verification through informal tests is not enough to achieve a safe composition, because they are not based on formal semantic models with which we are able to describe precisally a system s behaviour. In this context, formal methods provide ways to accurately specify systems through mathematical notations providing, among other benefits, more safety. The formal method CSP enables the specification of concurrent systems and verification of properties intrinsic to them, as well as the refinement among different models. Some approaches apply constraints using CSP, to check the behavior of composition between components, assisting in the verification of those components in advance. Hence, aiming to assist this process, considering that the software market increasingly requires more automation, reducing work and providing agility in business, this work presents a tool that automatizes the verification of composition among components, in which all complexity of formal language is kept hidden from users. Thus, through a simple interface, the tool BST (BRIC-Tool-Suport) helps to create and compose components, predicting, in advance, undesirable behaviors in the system, such as deadlocks

Sustentabilidade ambiental do cultivo intensivo de Tilápias (Oreochromis niloticus) em tanques-rede e a capacidade de suporte de quatro reservatórios em uma região semi-árida tropical

Intensive production of tilápias, in cages or net tanks, has been proposed as an alternative to increase fish production, that would generate income and offer animal protein in different tropical and subtropical countries. However, this system of production enriches the aquatic environment with nutrients, principally nitrogen and phosphor derived from the dejections of the metabolism of food and eventual food surpluses consumed by the fishes; the alimentation of the fishes in this production modality is dependent on fish food. The emission of these nutritions in levels above the limit that the system is capable metabolize can provoke a phenomenon called eutrofization, putting in risk the quality of water for public and for fish production activities. In this context the work had as a goal to evaluate the trófico state of the four reservoirs for intensive production of tilapias in net-tanks, in other words, he maximum fish production that the reservoirs are able to hold, keeping the desired quantity of nutrient concentrations in water for public use. The results of the four ecosystems in the Boqueirão de Parelhas reservoir showed that it s possible to have an intensive production of tilapias in net tanks, in this environment the annual average concentration of phosphor, was below the considered critical limits to deflagrate the process of eutrofization in semi-arid regions. The carrying capacity of the Boqueirão de Parelhas reservoir depends on the conversion of the feeding facts and phosphor content in the food but it should vary between 100 and 300 tons per year over a variation in the conversion feeding factor of 1,7 to 2,0:1 and a variation in the P in the food of 0,7 to 0,9%

Recurso de interface captcha: segurança e usabilidade na distinção entre humano e máquina

Com o intuito de impedir que computadores enviem mensagens automáticas se passando por usuários reais, desenvolvedores tem utilizado o recurso de interface CAPTCHA para distinguir o preenchimento de dados e submissões realizadas por humanos e por máquinas. Este trabalho apresenta as principais modalidades de CAPTCHAs e discute as implicações na usabilidade. Para tanto, foram aplicados questionários e realizados testes de usabilidade em três modalidades de CAPTCHA. Verificou-se que, embora os usuários tenham consciência da importância do uso do CAPTCHA como ferramenta de segurança, percebeu-se que tal recurso compromete a usabilidade, gerando insatisfação e em alguns casos, a desistência da realização da tarefa