An��lise morfom��trica e simulação das ��reas de preserva����o permanente de uma bacia hidrogr��fica

The morphometric characterization of watersheds is of great importance in assisting the planning of these areas to preserve the environment and maintain the quantity and quality of water production. The aim of this study was to characterize the morphology and simulate the areas of permanent preservation according to the Brazilian Forest Code of watershed of the ��gua-Fria stream. The studied area is located in the municipality of Bofete-SP, between the geographic coordinates: 48�� 09' 30" to 48�� 18' 30" longitude (WGr) and 22�� 58' 30" to 23�� 04' 30" latitude S. The results showed a 5th order micro watershed with an area of 152.43 km2 and low drainage density of 1.04 km/km2. Circularity was 0.51 and form factor was 0.41, which is considered low, and therefore with an oblong/oval shape. The sinuosity index of 1.29 revealed a tendency of rectilinear channels with compactness coefficient value of 1.38 and distance of runoff flow of 520m. Simulation of areas of permanent preservation shows an ideal model as the way springs and watercourses should be protected according to the Brazilian Forest Code, amounting to an area of 10.02 km2.

Hist��ria e natureza da ci��ncia no ensino de biologia: perfil e concep����es de professores em servi��o e de materiais did��ticos

Coordena����o de Aperfei��oamento de Pessoal de N��vel Superior (CAPES)

Detec����o e quantifica����o eletroqu��mica de subst��ncias de interesse cl��nico, ambiental e forense utilizando eletrodo de pasta de grafite modificado com trisilanol poss ligado a suportes porosos e eletrodos impressos obtidos via screen-printed

Coordena����o de Aperfei��oamento de Pessoal de N��vel Superior (CAPES)

Testes convencionais e empregando Micro-CT na avalia����o de propriedades f��sico-qu��micas de materiais retrobturadores e cimentos endod��nticos

Funda����o de Amparo �� Pesquisa do Estado de S��o Paulo (FAPESP)

Benef��cios na execu����o de uma obra sustent��vel em contrapartida aos métodos tradicionais da constru����o civil

The civil construction sector in Brazil is, simultaneously, a necessity that drives the economy and an evil that degrades the environment. Simple choices adopted in an enterprise can make big difference in harm caused by constructive practices, minimizing its harmful to the environment and making it sustainable. These choices, however, involve the use of materials and techniques often unknown by the builders, since the construction industry is very traditional. Even worse, the eco-friendly materials and sustainable techniques also face another obstacle to its use: the prejudice. Builders and customers prefer traditional methods to sustain belief that they present lower quality and higher price. This work raises awareness of the urgency with traditional methods must be overridden, showing practical and simple ways for this replacement, as well as confirm the quality equal to or even higher in the use of alternative materials and techniques, without addition in cost. Thus, the benefits are generated for all parties involved, from builders to residents

Modelagem e simulação de ciclos a g��s com resfriamento de ar na entrada

The optimization of energy generation systems has become a key issue for technological and social development, mainly in developing countries, where the electricity consumption rises sharply. Gas turbine cycle is an electricity generating system, which studies have demonstrated that inlet air cooling increases net power and thermal efficiency. Thus, this study intends to quantify these parameters for environments with different ambient temperature and relative humidity. Two types of air cooling were used: evaporative and absorption systems. The configuration parameters only with the gas turbine cycle were compared to those whose configuration allowed cooling. First, it was analyzed only evaporative cooling. Next, the absorption system was used for analysis. The last configuration mixed these two methods, dividing equally its flow. The results showed that thermal efficiency and net power increase in any case of cooling, with absorption system more advantageous in terms of generated energy, where an increase between 1 and 2 MW was observed, depending on the ambient conditions . When the two methods were working together at low relative humidity, it showed a thermal efficiency increase compared to absorption system, up to 2.4%. Evaporative cooling was less effective, but it is a good and cheap possibility to increase the cycle parameters at high temperature and low relative humidity

Simulação da suspens��o tipo duplo A de um ve��culo off-road atrav��s do hist��rico de excita����o do solo

The search for mechanical components validation methods, employed in product development sector, becomes more avid for less expensive solutions. As a result, programs that can simulate forces acting on a given part through finite element method are gaining more space in the market, once this process consumes less capital when compared to currently-employed empirical validation. This article shows the simulation of an off-road prototype suspension through such technique, using ground excitation history coming from field measurements and also by making use of a specific tool for obtaining dynamic loads from the model in question. The results shown at the end is key for future enhancements aiming mass reduction, for example, that may be executed on the prototype suspension system discussed here

Métodos de sele����o de pessoal: discuss��es preliminares sob o enfoque do behaviorismo radical

A sele����o de pessoal visa a introduzir na organiza����o os candidatos mais apropriados as suas necessidades. Existe uma car��ncia de literatura behaviorista radical acerca desse tema, sendo necess��rio o desenvolvimento de trabalhos que orientem atua����es coerentes com essa teoria. O objetivo deste estudo �� discutir os métodos utilizados na sele����o �� luz dos pressupostos conceituais do behaviorismo radical. Os métodos de sele����o existentes s��o analisados e discutidos em termos de aumento do controle das vari��veis presentes no contexto da sele����o a fim de proceder �� identifica����o dos repert��rios comportamentais dos candidatos. Prop��e-se uma an��lise de cargo baseada nos conceitos behavioristas, discute-se a possibilidade de condu����o de entrevistas de sele����o focadas no comportamento bem como o uso de t��cnicas de simulação que permitam a identifica����o de repert��rios comportamentais. Conclui-se que �� necess��rio desenvolver discuss��es te��ricas e instrumentos operacionais facilitadores de uma pr��tica psicol��gica vinculada aos pressupostos behavioristas radicais.

Benef��cios na execu����o de uma obra sustent��vel em contrapartida aos métodos tradicionais da constru����o civil

The civil construction sector in Brazil is, simultaneously, a necessity that drives the economy and an evil that degrades the environment. Simple choices adopted in an enterprise can make big difference in harm caused by constructive practices, minimizing its harmful to the environment and making it sustainable. These choices, however, involve the use of materials and techniques often unknown by the builders, since the construction industry is very traditional. Even worse, the eco-friendly materials and sustainable techniques also face another obstacle to its use: the prejudice. Builders and customers prefer traditional methods to sustain belief that they present lower quality and higher price. This work raises awareness of the urgency with traditional methods must be overridden, showing practical and simple ways for this replacement, as well as confirm the quality equal to or even higher in the use of alternative materials and techniques, without addition in cost. Thus, the benefits are generated for all parties involved, from builders to residents

Modelagem e simulação de ciclos a g��s com resfriamento de ar na entrada

The optimization of energy generation systems has become a key issue for technological and social development, mainly in developing countries, where the electricity consumption rises sharply. Gas turbine cycle is an electricity generating system, which studies have demonstrated that inlet air cooling increases net power and thermal efficiency. Thus, this study intends to quantify these parameters for environments with different ambient temperature and relative humidity. Two types of air cooling were used: evaporative and absorption systems. The configuration parameters only with the gas turbine cycle were compared to those whose configuration allowed cooling. First, it was analyzed only evaporative cooling. Next, the absorption system was used for analysis. The last configuration mixed these two methods, dividing equally its flow. The results showed that thermal efficiency and net power increase in any case of cooling, with absorption system more advantageous in terms of generated energy, where an increase between 1 and 2 MW was observed, depending on the ambient conditions . When the two methods were working together at low relative humidity, it showed a thermal efficiency increase compared to absorption system, up to 2.4%. Evaporative cooling was less effective, but it is a good and cheap possibility to increase the cycle parameters at high temperature and low relative humidity

Simulação da suspens��o tipo duplo A de um ve��culo off-road atrav��s do hist��rico de excita����o do solo

The search for mechanical components validation methods, employed in product development sector, becomes more avid for less expensive solutions. As a result, programs that can simulate forces acting on a given part through finite element method are gaining more space in the market, once this process consumes less capital when compared to currently-employed empirical validation. This article shows the simulation of an off-road prototype suspension through such technique, using ground excitation history coming from field measurements and also by making use of a specific tool for obtaining dynamic loads from the model in question. The results shown at the end is key for future enhancements aiming mass reduction, for example, that may be executed on the prototype suspension system discussed here

Compara����o entre os métodos de aplica����o de fluido de corte convencional e otimizado na retifica����o plana de cer��micas

Com o grande crescimento tecnol��gico e a necessidade de melhoria, um dos materiais que ganhou uma grande gama na ��rea da engenharia mec��nica �� a cer��mica, pois possui vantagens f��sico-qu��micas e propriedades mec��nicas significativas sobre o a��o. Entretanto, sua usinagem �� um processo dif��cil e delicado, que requer ainda uma grande aten����o em rela����o ao seu estudo. Assim, o processo de retifica����o �� um dos métodos que tem apresentado bons resultados, por��m um grande problema acerca de tal processo �� o uso excessivo de fluidos de corte, o que se tornou uma preocupa����o mundial, j�� que os fluidos apresentam graves problemas socioambientais, al��m disso, o fluido de corte �� respons��vel por uma grande parte do custo final do processo, provocando, desse modo, um grande interesse em pesquisas referentes a métodos alternativos de forma a reduzir o consumo e melhorar as caracter��sticas do fluido de corte utilizado. Este trabalho visa comparar duas t��cnicas de lubri-refrigera����o, o m��todo convencional e a Lubrifica����o Otimizada. O uso do m��todo otimizado �� uma alternativa �� diminui����o do volume de fluido utilizado, j�� que este tem como princ��pio a aplica����o de uma menor quantidade de fluido de corte com uma alta velocidade, localmente aplicada, ou seja, com essa redu����o benef��cios ambientais e socioecon��micas s��o obtidos. A an��lise do trabalho ser�� feita a partir da avalia����o das vari��veis de sa��da do processo de retifica����o plana tais como o comportamento rugosidade e desgaste do rebolo, j�� que por elas �� poss��vel avaliar o processo em rela����o a qualidade da pe��a versus custo. Com essas analises, pretende-se avaliar se a t��cnica otimizada �� vi��vel a substitui����o da refrigera����o convencional na retifica����o plana de cer��micas.

Simulação tridimensional adaptativa da separa����o das fases de uma mistura bif��sica usando a equa����o de Cahn-Hilliard

Simulamos a separa����o dos componentes de uma mistura bif��sica com a equa����o de Cahn-Hilliard. Esta equa����o cont��m intrincados termos n��o lineares e derivadas de alta ordem. Al��m disso, a delgada regi��o de transi����o entre os componentes da mistura requer muita resolu����o. Assim, determinar a solu����o num��rica da equa����o de Cahn-Hilliard n��o �� uma tarefa f��cil, principalmente em tr��s dimens��es. Conseguimos a resolu����o exigida no tempo usando uma discretiza����o semi-impl��cita de segunda ordem. No espa��o, obtemos a precis��o requerida utilizando malhas refinadas localmente com a estrat��gia AMR. Essas malhas se adaptam dinamicamente para recobrir a regi��o de transi����o. O sistema linear proveniente da discretiza����o �� solucionado por interm��dio de t��cnicas multin��vel-multigrid.

Métodos de adequa����o e diagn��stico em modelos de sobreviv��ncia din��micos

A an��lise de dados de sobreviv��ncia tem sido tradicionalmente baseada no modelo de regress��o de Cox (COX, 1972). No entanto, a suposi����o de taxas de falha proporcionais assumida para esse modelo pode n��o ser atendida em diversas situa����es pr��ticas. Essa restri����o do modelo de Cox tem gerado interesse em abordagens alternativas, dentre elas os modelos din��micos que permitem efeito das covari��veis variando no tempo. Neste trabalho, foram revisados os principais modelos de sobreviv��ncia din��micos com estrutura aditiva e multiplicativa nos contextos n��o param��trico e semiparam��trico. Métodos gr��ficos baseados em res��duos foram apresentados com a finalidade de avaliar a qualidade de ajuste desses modelos. Uma vers��o tempo-dependente da ��rea sob a curva ROC, denotada por AUC(t), foi proposta com a finalidade de avaliar e comparar a qualidade de predi����o entre modelos de sobreviv��ncia com estruturas aditiva e multiplicativa. O desempenho da AUC(t) foi avaliado por meio de um estudo de simulação. Dados de tr��s estudos descritos na literatura foram tamb��m analisados para ilustrar ou complementar os cen��rios que foram considerados no estudo de simulação. De modo geral, os resultados obtidos indicaram que os métodos gr��ficos apresentados para avaliar a adequa����o dos modelos em conjunto com a AUC(t) se constituem em um conjunto de ferramentas estat��sticas ��teis para o pr��posito de avaliar modelos de sobreviv��ncia din��micos nos contextos n��o param��trico e semiparam��trico. Al��m disso, a aplica����o desse conjunto de ferramentas em alguns conjuntos de dados evidenciou que se, por um lado, os modelos din��micos s��o atrativos por permitirem covari��veis tempo-dependentes, por outro lado podem n��o ser apropriados para todos os conjuntos de dados, tendo em vista que estima����o pode apresentar restri����es para alguns deles.