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21.
A general input-to-state stability (ISS)-type small-gain result is presented. It specializes to a small-gain theorem for ISS operators, and it also recovers the classical statement for ISS systems in state-space form. In addition, we highlight applications to incrementally stable systems, detectable systems, and to interconnections of stable systems.  相似文献   
22.
Digital libraries of scientific articles contain collections of digital objects that are usually described by bibliographic metadata records. These records can be acquired from different sources and be represented using several metadata standards. These metadata standards may be heterogeneous in both, content and structure. All of this implies that many records may be duplicated in the repository, thus affecting the quality of services, such as searching and browsing. In this article we present an approach that identifies duplicated bibliographic metadata records in an efficient and effective way. We propose similarity functions especially designed for the digital library domain and experimentally evaluate them. Our results show that the proposed functions improve the quality of metadata deduplication up to 188% compared to four different baselines. We also show that our approach achieves statistical equivalent results when compared to a state-of-the-art method for replica identification based on genetic programming, without the burden and cost of any training process.  相似文献   
23.
The aims of this study were (a) to assess the ability of the rating of perceived exertion (RPE) to predict performance (i.e. number of vertical jumps performed to a fixed jump height) of an intermittent vertical jump exercise, and (b) to determine the ability of RPE to describe the physiological demand of such exercise. Eight healthy men performed intermittent vertical jumps with rest periods of 4, 5, and 6 s until fatigue. Heart rate and RPE were recorded every five jumps throughout the sessions. The number of vertical jumps performed was also recorded. Random coefficient growth curve analysis identified relationships between the number of vertical jumps and both RPE and heart rate for which there were similar slopes. In addition, there were no differences between individual slopes and the mean slope for either RPE or heart rate. Moreover, RPE and number of jumps were highly correlated throughout all sessions (r = 0.97-0.99; P < 0.001), as were RPE and heart rate (r = 0.93-0.97; P < 0.001). The findings suggest that RPE can both predict the performance of intermittent vertical jump exercise and describe the physiological demands of such exercise.  相似文献   
24.
The authors present the feasibility and acceptability of a parent sexuality education program led by peer educators in community settings. They also report the results of an outcome evaluation with 71 parents who were randomized to the intervention or a control group and surveyed one month prior to and six months after the four-week intervention. The program was highly feasible and acceptable to participants, and the curriculum was implemented with a high level of fidelity and facilitator quality. Pilot data show promising outcomes for increasing parental knowledge, communication, and monitoring of their adolescent children.  相似文献   
25.
Bioinformatics education can be broadly defined as the teaching and learning of the use of computer and information technology, along with mathematical and statistical analysis for gathering, storing, analyzing, interpreting, and integrating data to solve biological problems. The recent surge of genomics, proteomics, and structural biology in the potential advancement of research and development in complex biomedical systems has created a need for an educated workforce in bioinformatics. However, effectively integrating bioinformatics education through formal and informal educational settings has been a challenge due in part to its cross-disciplinary nature. In this article, we seek to provide an overview of the state of bioinformatics education. This article identifies: 1) current approaches of bioinformatics education at the undergraduate and graduate levels; 2) the most common concepts and skills being taught in bioinformatics education; 3) pedagogical approaches and methods of delivery for conveying bioinformatics concepts and skills; and 4) assessment results on the impact of these programs, approaches, and methods in students’ attitudes or learning. Based on these findings, it is our goal to describe the landscape of scholarly work in this area and, as a result, identify opportunities and challenges in bioinformatics education.  相似文献   
26.
Abstract

The modernisation of potato production in the Ecuadorian highlands is related to an intensive use of pesticides. In this context, by means of ethnographic methodologies and discourse analysis tools, this study was aimed to determine the influence of household arrangements, local institutions and social differentiation in the management of potato production and pesticide use. Potato production involves all household members and generates occupational risks, but also household-level accidents. This study has determined that children and teenagers form the group most vulnerable to intoxication with pesticides. Four social dimensions that integrate pesticides in the local social dynamics were determined: health-beliefs, gender identity, social identity, and economical progress reliance by means of potato production. Intense potato production and comoditisation of nature is contributing to a progressive social stratification, which is causing a group of peasant households to emerge as the poorest group and vulnerable to occupational risks by chronic pesticide exposure.  相似文献   
27.
Abstract

As developing countries gradually rely less upon agriculture for rural income, rural economies require new solutions to access knowledge and information systems for rural development. Non-agricultural rural knowledge and information systems can play a significant role in developing and disseminating successful strategies to escape rural poverty. This paper discusses the challenges of developing rural knowledge and information systems, practical and vital in facilitating rural development in the 21st century.  相似文献   
28.
Aunque los objetivos curriculares actuales se plantean la enseñanza del lenguaje escrito de modo que permita utilizarlo como instrumento para el aprendizaje, el hecho es que esta enseñanza de la lectoescritura como medio se contempla como un fin en sí mismo, es decir, con materiales y contenidos literarios y no de áreas disciplinares específicas en que el niño se tendrá que mover a lo largo de toda la escolaridad. En este artículo se presenta un programa experimentado con éxito en las áreas de ciencias naturales y sociales para mejorar en los alumnos estas necesarias estrategias de comprensión y estudio.  相似文献   
29.
Utilizar el ordenador en la escuela no es una garantía de éxito didáctico si no se cumplen algunos requisitos, pero constituye una ayuda no suficientemente explorada en la mayoría de las materias. En el caso de las matemáticas, el ordenador permite diseñar actividades altamente motivadoras para el niño, a la vez que facilitar la integración de diferentes tipos de códigos, objetivos ambos difíciles de conseguir en los formatos de papel y lápiz habituales en las didácticas tradicionales. El autor de este artículo pasa revista a una serie de micromundos informáticos que permiten al profesor y al alumno librarse de tareas rutinarias y dedicarse a la exploración de las posibilidades del lenguaje matemático, a la verdadera tarea de aprender.  相似文献   
30.
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