PID stabilization of a class of time delay systems

In this paper we use the Hermite-Biehler theorem to establish results for the design of proportional plus integral plus derivative (PID) controllers concerning a class of time delay systems. Using the property of interlacing at high frequencies of the class of systems considered and linear programming we obtain the set of all stabilizing PID controllers. © 2005 IEEE.

Third-body perturbation in the case of elliptic orbits for the disturbing body

In the present work it is presented a semi-analytical and a numerical study of the perturbation caused in a spacecraft by a third body using a double averaged analytical model with the disturbing function expanded in Legendre polynomials up to the second-order. The important reason for this procedure is to eliminate the terms due to the short time periodic motion of the spacecraft and to show smooth curves for the evolution of the mean orbital elements for a long time period. The aim of this study is to calculate the effect of lunar perturbations on the orbits of spacecrafts that are traveling around the Earth. It is presented an analysis of the stability of a near-circular orbit and a study to know under which conditions this orbit remains near-circular. A study of the equatorial orbits is also performed.

A simple derivation of the Lindblad equation

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Sustainable urban energy planning: The case study of a tropical city

The urbanization of modern societies has imposed to the planners and decision-makers a more precise attention to facts not considered before. Several aspects, such as the energy availability and the deleterious effect of pollution on the populations, must be considered in the policy decisions of cities urbanization. The current paradigm presents centralized power stations supplying a city, and a combination of technologies may compose the energy mix of a country, such as thermal power plants, hydroelectric plants, wind systems and solar-based systems, with their corresponding emission pattern. A goal programming multi-objective optimization model is presented for the electric expansion analysis of a tropical city, and also a case study for the city of Guaratinguetá, Brazil, considering a particular wind and solar radiation patterns established according to actual data and modeled via the time series analysis method. Scenarios are proposed and the results of single environmental objective, single economic objective and goal programming multi-objective modeling are discussed. The consequences of each dispatch decision, which considers pollutant emission exportation to the neighborhood or the need of supplementing electricity by purchasing it from the public electric power grid, are discussed. The results revealed energetic dispatch for the alternatives studied and the optimum environmental and economic solution was obtained. © 2012 Elsevier Ltd.

A hybrid multi-population genetic algorithm applied to solve the multi-level capacitated lot sizing problem with backlogging

The present paper proposes a new hybrid multi-population genetic algorithm (HMPGA) as an approach to solve the multi-level capacitated lot sizing problem with backlogging. This method combines a multi-population based metaheuristic using fix-and-optimize heuristic and mathematical programming techniques. A total of four test sets from the MULTILSB (Multi-Item Lot-Sizing with Backlogging) library are solved and the results are compared with those reached by two other methods recently published. The results have shown that HMPGA had a better performance for most of the test sets solved, specially when longer computing time is given. © 2012 Elsevier Ltd.

Modelo de Marcus, elementos de matriz de tunelamento, efeitos de solvente e controle nuclear em reações de transferência de elétrons

This paper aims to give an initial presentation to physics students of the area of electron transfer, addressing its major aspects. The subject is then presented in an introductory way, highlighting and discussing the key points. Primarily, the problem is approached in a simplified manner through a two-state system, and aspects of calculating the matrix-element are discussed. Then, the electron transfer problem, influenced by nuclear reaction coordinates, is addressed and treated by the Marcus theory. Time scales and the concepts of adiabatic and nonadiabatic phenomena are discussed in the context of electron transfer. The classical, semi-classical and quantum formalisms of for the nuclear reactions coordinates are presented, and aspects of solvents are also discussed. Finally, we conclude by examining some recent examples of problems discussed in the literature.

Laboratório remoto de qualidade da energia elétrica

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Modelo de programação matemática para controle do crescimento da vegetação sob redes de distribuição de energia elétrica

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Ecomorfologia e uso de recursos das espécies de Chironius (Serpentes, Colubridae) na Serra do Mar

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Ação dos ésteres do ácido ricinoléico do óleo de mamona (Ricinus communis) sobre as células dos ovários de Rhipicephalus sanguineus (Acari: Ixodidae): dinâmica da vitelogênese

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Germinação de sementes de Passiflora setacea DC: temperatura, luz e reguladores vegetais

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Qualidade de sistemas de plantio em cultivares de cana-de-açúcar

Pós-graduação em Agronomia (Ciência do Solo) - FCAV

Efeito de colágeno hidrolisado sobre a qualidade tecnológica de queijo Minas frescal light

Pós-graduação em Engenharia e Ciência de Alimentos - IBILCE

Acúmulo de saberes e experiência formativa

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Métodos analíticos, numéricos e experimentais para o cálculo de ondas de impacto em meios líquidos

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)