Coupled deformation-flow analysis for methane hydrate production by depressurized wells

A formulation for coupled flow-deformation analysis of methane-hydrate extraction problems is presented. By assuming that the hydrate does not flow, a two phase flow formulation is considered, based on Darcy's law and capillary pressure relation. The formulation is implemented in the finite difference code FLAC. The code was used to investigate the stability of a methane extraction well by depressurizing the well. © 2005 Taylor & Francis Group, London.

Cost-Saving production technologies and strategic delegation

This work analyzes a managerial delegation model in which firms that produce a differentiated good can choose between two production technologies: a low marginal cost technology and a high marginal cost technology. For the former to be adopted more investment is needed than for the latter. By giving managers of firms an incentive scheme based on a linear combination of profit and sales revenue, we find that Bertrand competition provides a stronger incentive to adopt the cost-saving technology than the strict profit maximization case. However, the results may be reversed under Cournot competition. We show that if the degree of product substitutability is sufficiently low (high), the incentive to adopt the cost-saving technology is larger under strict profit maximization (strategic delegation).

Carne e bits : reflexões sobre a indiscernibilidade das fronteiras entre mentes e máquinas e os sistemas cognitivos híbridos

Faz reflexões sobre as várias formas de relação entre sujeitos e objetos-técnicos, com ênfase para a utilização dos computadores digitais e, particularmente, os softwares chamados agentes inteligentes. Analisa o espaço e suas mudanças qualitativas na atualidade, a partir do conceito do espaço como produção humana, analisando como as transformações em curso no ambiente afetam nossas subjetividades e, reciprocamente, como afetamos nossos ambientes. Discutidas as possibilidades de sobrevivência do homem nu nesses novos espaços, sem que esteja devidamente atualizado com as últimas novidades tecnológicas - próteses sensoriais e motoras. Perpassa a discussão sobre o pensamento que se utiliza do espaço como elemento constituinte do próprio pensamento e reflete sobre o espaço abstrato por excelência, os mundos virtuais. Discute o padrão de apropriação de artefatos pelo homem e seus efeitos na subjetividade, a manutenção do padrão de apropriação dos objetos-técnicos materiais em relação às formas de apropriação dos objetos-técnicos intangíveis (softwares). Traz reflexões sobre a possibilidade de autonomização completa dos agentes inteligentes e a sua instituição, ipso facto, como agentes - a chamada Inteligência Artificial.

Innovative reaction systems for acetal (1,1 diethoxy butane) production from renewable sources

370 p.: il., graf.

Overcoming hurdles to sustainable industrial fisheries production

(PDF has 25 pages.)

Breed effect on quality veal production in mountain areas: Emphasis on meat

This study was designed to compare the quality of veal produced from ‘Tudanca x Charolais’ cross (n=6) and Limousin (n=6) breeds when allowed to feed freely on mountain pastures and suckle naturally from birth to 7 months of age. After 80 days of age calves also had access to concentrate (maximum of 3 Kg/day), while mothers did not. At slaughter, Limousin calves were heavier (P<0.01) and provided better carcass yield (P<0.05) and conformation (P<0.001) than Tudanca calves. Tudanca beef provided higher fat content (P<0.05) was less tough (P<0.05), and was scored as more tender and juicy (P<0.1) with higher acceptability than Limousin beef (P<0.1). In general, Tudanca had a better fatty acid profile than Limousin beef, especially in terms of the content of polyunsaturated (P<0.05), long-chain polyunsaturated fatty acids (P<0.05) and their n-6/n-3 ratios (P<0.1), as well as vaccenic acid (P<0.1) and the overall trans-18:1 isomer profile.

Spawn production in hapas

(4 pp.)

Spawn production in hatcheries

(4 p.)

Spawn production of common carp

(4 p.)

Fry production: nursing spawn

(4 p.)