Postural control of the trunk in response to lateral support surface translations during trunk movement and loading

The postural response to translation of the support surface may be influenced by the performance of an ongoing voluntary task. This study was designed to test this proposal by applying lateral perturbations while subjects handled a load in the frontal plane. Measurements were made of medio-lateral displacement of the centre of pressure, angular displacement of the trunk and thigh in the frontal plane and intra-abdominal pressure. Subjects were translated randomly to the left and right in a variety of conditions that involved standing either quietly or with a 5 kg load in their left hand, which they were required either to hold statically or to lift or lower. The results indicate that when the perturbation occurred towards the loaded left side the subjects were able to return their centre of pressure, trunk and thigh rapidly and accurately to the initial position. However, when the perturbation occurred towards the right (away from the load) this correction was delayed and associated with multiple changes in direction of movement, suggesting decreased efficiency of the postural response. This reduced efficiency can be explained by a conflict between the motor commands for the ongoing voluntary task and the postural response, and/or by the mechanical effect of the asymmetrical addition of load to the trunk.

A feature-based object-oriented expert system to model and support product design

In this paper a computer program to model and support product design is presented. The product is represented through a hierarchical structure that allows the user to navigate across the product’s components, and it aims at facilitating each step of the detail design process. A graphical interface was also developed, which shows visually to the user the contents of the product structure. Features are used as building blocks for the parts that compose the product, and object-oriented methodology was used as a means to implement the product structure. Finally, an expert system was also implemented, whose knowledge base rules help the user design a product that meets design and manufacturing requirements.

Activities of the ECLAC system to promote and support technical cooperation among developing countries and regions during the 2002-2003 biennium: note by the Secretariat

Includes bibliography

Activities of the ECLAC system to promote and support South-South cooperation during the 2004-2005 biennium. Note by the Secretariat

Includes bibliography

Activities of the ECLAC system to promote and support South-South cooperation during the 2006-2007 biennium

Includes bibliography

Activities of the ECLAC system to promote and support South-South cooperation during the 2010-2011 biennium

Versión en inglés disponible en Biblioteca

Actividades del sistema de la CEPAL para promover y apoyar la cooperación entre países y regiones en desarrollo = Activities of the ECLAC system to promote and support co-operation among developing countries and regions

Da cuenta de las principales actividades operacionales realizadas por el sistema de la CEPAL desde el 21 periodo de sesiones de la Comision, especialmente en el marco de su resolucion 486(XXI): Cooperacion tecnica y economica entre paises y regiones en desarrollo.

Actividades del sistema de la CEPAL para promover y apoyar la cooperación técnica entre países y regiones en desarrollo = Activities of the ECLAC system to promote and support technical co-operation among developing countries and regions

Incluye Bibliografía