A brief discussion about image quality and SEM methods for quantitative fractography of polymer composites

The methodology for fracture analysis of polymeric composites with scanning electron microscopes (SEM) is still under discussion. Many authors prefer to use sputter coating with a conductive material instead of applying low-voltage (LV) or variable-pressure (VP) methods, which preserves the original surfaces. The present work examines the effects of sputter coating with 25 nm of gold on the topography of carbon-epoxy composites fracture surfaces, using an atomic force microscope. Also, the influence of SEM imaging parameters on fractal measurements is evaluated for the VP-SEM and LV-SEM methods. It was observed that topographic measurements were not significantly affected by the gold coating at tested scale. Moreover, changes on SEM setup leads to nonlinear outcome on texture parameters, such as fractal dimension and entropy values. For VP-SEM or LV-SEM, fractal dimension and entropy values did not present any evident relation with image quality parameters, but the resolution must be optimized with imaging setup, accompanied by charge neutralization. © Wiley Periodicals, Inc.

Los foros intergubernamentales de la Comisión Económica para América Latina y el Caribe = Intergovernmental forums of the Economic Commission for Latin America and the Caribbean

Teniendo presente la posibilidad de que durante el vigésimo tercer período de sesiones de la CEPAL se considere el ingreso de nuevos miembros, se proporciona información y antecedentes sobre la creación y composición de la CEPAL, composición de las otras comisiones regionales de las Naciones Unidas, y lista de Estados miembros de la CEPAL.

Digital proficiency and digital inclusion: Comparison between students of computer science, public relations and engineering

New information and communication technologies may be useful for providing more in-depth knowledge to students in many ways, whether through online multimedia educational material, or through online debates with colleagues, teachers and other area professionals in a synchronous or asynchronous manner. This paper focuses on participation in online discussion in e-learning courses for promoting learning. Although an important theoretical aspect, an analysis of literature reveals there are few studies evaluating the personal and social aspects of online course users in a quantitative manner. This paper aims to introduce a method for diagnosing inclusion and digital proficiency and other personal aspects of the student through a case study comparing Information System, Public Relations and Engineering students at a public university in Brazil. Statistical analysis and analysis of variances (ANOVA) were used as the methodology for data analysis in order to understand existing relations between the components of the proposed method. The survey methodology was also used, in its online format, as a research instrument. The method is based on using online questionnaires that diagnose digital proficiency and time management, level of extroversion and social skills of the students. According to the sample studied, there is no strong correlation between digital proficiency and individual characteristics tied to the use of time, level of extroversion and social skills of students. The differences in course grades for some components are partly due to subject 'Introduction to Economics' being offered to freshmen in Public Relations, whereas subject 'Economics in Engineering' is offered in the final semesters of Engineering and Information Systems courses. Therefore, the difference could be more tied to the respondent's age than to the course. Information Systems students were observed to be older, with access to computers and Internet at the workplace, compared to the other students who access the Internet more often from home. This paper presents a pilot study aimed at conducting a diagnosis that permits proposing actions for information and communication technology to contribute towards student education. Three levels of digital inclusion are described as a scale to measure whether information technology increases personal performance and professional knowledge and skills. This study may be useful for other readers interested in themes related to education in engineering. © 2013 IEEE.

Guía para orientar los debates de los puntos del temario de la Reunión = Suggested guide for discussion of the items on the agenda of the meeting

Contiene pautas para la reunion donde se analizaran temas tales como: el desencadenamiento de la crisis y la reaccion de la politica economica, el marco conceptual para la reorientacion del desarrollo latinoamericano, la transformacion del Estado, los agentes sociales y los sistemas politicos.

Esquema para discusión: Programa de Acción para la Mujer en América Latina y el Caribe 1995-2015 = Outline for discussion of ECLAC Programme of Action for Women in Latin America and the Caribbean 1995-2015

Incluye Bibliografía

Dimensions of poverty and directions of measurement: talking point for discussion

Includes bibliography

Population, social equity and changing production patterns

Includes bibliography

Framework for implementation of the outcomes of the World Summit on Sustainable Development (WSSD) in the small island developing states of the Caribbean subregion

Includes bibliography

Survey of the needs for technical assistance and the ability to provide such: a discussion of the survey findings and of the principles and mechanism of technical co-operation among developing countries

Includes bibliography

Reconceptualizing social indicators in the Caribbean: a review and discussion

Includes bibliography

Views and thinking regarding the application of computer technology for development in the ECLA region: draft for discussion

Includes bibliography

Mecanismos internacionales para el financiamiento del desarrollo científico y tecnológico: guía de discusión para su análisis y diseño = International machinery for the financing of scientific and technological development: discussion guidelines for its analysis and design

Incluye Bibliografía

Mediação em fóruns educacionais de curso online de língua estrangeira (espanhol)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)