Neste trabalho estudam-se problemas de dimensionamento de lotes em que as decisões clássicas do dimensionamento dos lotes de produção são tomadas considerando também os custos do transporte dos produtos fabricados. Estes custos estão associados ao número de paletes ou caminhões necessários para empacotar e/ou transportar os produtos produzidos desde a fábrica até o depósito. São consideradas três extensões de um modelo de programação inteira mista, apresentado na literatura, representando casos mais gerais que ocorrem na prática. Estes modelos são testados e avaliados usando um pacote de otimização. Também é apresentado um método heurístico de resolução, baseado em relaxação Lagrangiana, para uma das extensões propostas.

In this paper, capacitated lot sizing problems in which the classical lot sizing decisions are made considering the transportation costs of the manufactured products were studied. These costs are related to the necessary number of pallets or trucks to pack and/or transport the products from the factory to the warehouse. Three extensions of a mixed integer linear programming model from the literature are considered, representing general cases that are commonly found in companies. These models are tested and evaluated using an optimization package, and a Lagrangian heuristic was developed for one of the extensions proposed.

Nesse estudo foi avaliada a capacidade de biossorção de íons chumbo em solução aquosa pela bactéria Rhodococcus opacus. Avaliou-se em batelada o efeito do pH da solução, concentração da biomassa, tempo de contato e concentração inicial do metal. A cinética adequou-se melhor ao modelo de pseudo-segunda ordem. Empregaram-se as isotermas de Langmuir e Freundlich para representar o processo de sorção no equilíbrio. O valor da capacidade máxima de captação (q max) obtida pelo modelo de Langmuir foi de 94,34 mg g-1. No ensaio de biossorção competitiva a remoção do chumbo foi afetada pela presença de outros metais na solução.

The biosorption of lead ions from aqueous solution by Rhodococcus opacus bacteria was evaluated in this study. The effects of the solution's pH, biomass concentration, contact time and initial metal concentration were studied in batch experiments. The results of the kinetics studies revealed that the biosorption of lead on R. opacus cells followed pseudo-second order kinetics. The equilibrium data was analyzed using Freundlich and Langmuir models. The maximum uptake capacity (q max) obtained by the Langmuir adsorption model was 94.34 mg.g-1. In the competitive biosorption experiments, the lead removal was affected by the presence of other metal ions in the solution.

Neste trabalho estuda-se um problema de dimensionamento de lotes e distribuição que envolve além de custos de estoques, produção e preparação, custos de transportes para o armazém da empresa. Os custos logísticos estão associados aos contêineres necessários para empacotar os produtos produzidos. A empresa negocia um contrato de longo prazo onde um custo fixo por período é associado ao transporte dos itens, em contrapartida um limite de contêineres é disponibilizado com custo mais baixo que o custo padrão. Caso ocorra um aumento ocasional de demanda, novos contêineres podem ser utilizados, no entanto, seu custo é mais elevado. Um modelo matemático foi proposto na literatura e resolvido utilizando uma heurística Lagrangiana. No presente trabalho a resolução do problema por uma heurística Lagrangiana/surrogate é avaliada. Além disso, é considerada uma extensão do modelo da literatura adicionando restrições de capacidade e permitindo atraso no atendimento a demanda. Testes computacionais mostraram que a heurística Lagrangiana/surrogate é competitiva especialmente quando se têm restrições de capacidade apertada.

The aim of this work was to study a distribution and lot-sizing problem that considers costs with transportation to a company warehouse as well as, inventory, production and setup costs. The logistic costs are associated with necessary containers to pack produced items. The company negotiates a long-term contract in which a fixed cost per period is associated with the transportation of the items. On the other hand, a limited number of containers are available with a lower cost than the average cost. If an occasional demand increase occurs, other containers can be utilized; however, their costs are higher. A mathematical model was proposed in the literature and solved using the Lagrangian heuristic. Here, the use of the Lagrangian/surrogate heuristic to solve the problem is evaluated. Moreover, an extension of the literature model is considered adding capacity constraints and allowing backlogging. Computational tests show that Lagrangian/surrogate heuristics are competitive, especially when the capacity constraints are tight.

The feeding behavior and the food preference was studied in P. expansa (Schweigger, 1812) P. unifilis (Troschel, 1848) and P. sextuberculata (Cornalia, 1849). The method used for feeding behavior and food preference was the sampling of all occurrences. The Students' t test was applied on the food items, to compare differences during the development of each species. The main conclusions are: feeding behavior for food, except alive animals, is divided in foraging, approach, olfactory recognition, capture, laceration and ingestion; the persecution behavior was observed for prey activity; cleptoparasitism occurs in the three species and neustophagia mechanism was detected in P. unifilis; P. sextuberculata shows to be almost only carnivorous and P. expansa and P. unifilis show to be omnivorous; P. expansa can be considered more herbivorous in captivity than P. unifilis during the age between one and five years old and more than five years old; P. expansa is more sensitive than P. unifilis concerning the alteration of the food place, mainly the meat, decreasing its consumption, if it is put on a dry place.

Since 1985 the biology and behavior of Phrynops hilarii (Duméril & Bibron, 1835) at São Paulo Zoo is being studied. Feeding behavior is divided in five phases (foraging, approach, capture, dilaceration and ingestion), but not necessarily all of them happen. During phase 1 the food or prey seems to be visually located. During phase 2 the food itens and stationaty preys are approached and examined by olfaction. Moving preys are pursued and there is no olfactory examination. During phase 3 the food is captured by suction. When food is bigger than turtle mouth it is dilacerated by one or both forefeet used alternately (phase 4). Ingestion is accomplished by gradual suction (phase 5). Intra and inter-specific cleptoparasitism was observed. Success in capture and ingestion of food seems not be dependent on species or size of the turtle. Adults, young, and hatchlings of P. hilarii are primarily carnivorous and vegetables were rarely eaten.

Artificial incubation of 558 eggs from 70 clutches of Trachemys dorbignyi (Duméril & Bibron, 1835) were performed at São Paulo Zoo during 1992 and 1993. Hatching occurred when eggs were incubated between 25 and 31.5oC. Incubation time varied from 54 (at 31.5oC) to 120 days (at 25oC), similarly to Trachemys scripla sspp. Hatchling used the caruncle to made small incisions in the egg shell, latter enlarged by movements of the head and forefeet. Hatching usually lasted from one to two days. Newborn's carapace and plastron showed their natural form few hours after the emergence from the egg shell. During the third or fourth week, caruncle usually disappeared, and yolk sac was completely absorbed. Average (x±sd) measures of newborn were 3.55±0.18cm of carapace length, 3.35±0.17cm of plastron length, and 10.73±1.36g of weight.

Phrynops geofroanus is a carnivorous side-necked turtle. Its feeding behavior is divided in foraging, approach, capture, dilaceration and ingestion, but not necessary all these phases happen. Location of food seems to be visual and recognition olfactory. When food is an agile prey approach is done by pursuing and there is no olfactory recognition.