An integrated approach for analysing and assessing the performance of virtual learning groups

Collaborative distance learning involves a variety of elements and factors that have to be considered and measured in order to analyse and assess group and individual performance more effectively and objectively. This paper presents an approach that integrates qualitative, social network analysis (SNA) and quantitative techniques for evaluating online collaborative learning interactions. Integration of various different data sources, tools and techniques provides a more complete and robust framework for group modelling and guarantees a more efficient evaluation of group effectiveness and individual competence. Our research relies on the analysis of a real, long-term, complex collaborative experience, which is initially evaluated in terms of principled criteria and a basic qualitative process. At the end of the experience, the coded student interactions are further analysed through the SNA technique to assess participatory aspects, identify the most effective groups and the most prominent actors. Finally, the approach is contrasted and completed through a statistical technique which sheds more light on the results obtained that far. The proposal draws a well-founded line toward the development of a principled framework for the monitoring and analysis of group interaction and group scaffolding which can be considered a major issue towards the actual application of the CSCL proposals to real classrooms.Peer ReviewedPostprint (author's final draft

A Real-Time Ball Detection Approach Using Convolutional Neural Networks

Ball detection is one of the most important tasks in the context of soccer-playing robots. The ball is a small moving object which can be blurred and occluded in many situations. Several neural network based methods with different architectures are proposed to deal with the ball detection. However, they are either neglecting to consider the computationally low resources of humanoid robots or highly depend on manually-tuned heuristic methods to extract the ball candidates. In this paper, we propose a new ball detection method for low-cost humanoid robots that can detect most soccer balls with a high accuracy rate of up to 97.17%. The proposed method is divided into two steps. First, some coarse regions that may contain a full ball are extracted using an iterative method employing an efficient integral image based feature. Then they are fed to a light-weight convolutional neural network to finalize the bounding box of a ball. We have evaluated the proposed approach using a comprehensive dataset and the experimental results show the efficiency of our method

Analysis methods for collaborative models and activities

Abstract. A classification of analysis methods for CSCL systems is presented which uses as one dimension the distinction into summary analysis and structural analysis and as another distinction different types of raw data: either user actions or state descriptions. The Cool Modes environment for collaborative modeling enables us to explore the whole spectrum of analysis methods. Action logging is based on the MatchMaker communication server underlying Cool Modes. Example instances for several analysis methods have been implemented in the Cool Modes framework.

Action-based collaboration analysis for group learning

This book describes a piece of innovative research into analyzing the actions and interactions of co-learners in computer-supported group learning environments. So far, in computersupported collaborative learning (CSCL) the computational facilities are mainly used to mediate communication and to provide interactive tools, e.g., for joint problem solving or to externalize and represent ideas in group discussions. Although the basic information about which users ’ communications and actions are available in the machine, it is usually not used to structure and support the collaborative learning process. After the limited success of “intelligent tutoring environments ” for individual learning, the expectation is not that collaborative learning should be intelligently controlled and directed by a machine. Yet, a certain degree of “insight ” on the part of the system environment into the structure and dynamics of the group learning process should lead to new ways of supporting and scaffolding the learning group. Without globally directing the learning process, the system can, for instance, identify specific needs of one learner or learning group which could be supported by other learners or tutors, i.e., it can help to manage human resources. Structuring and interpreting group learning processes on certain levels of aggregation and abstraction can serve as a starting poin

Escherichia coli enterotoxigénica en síndrome diarreico en bovinos de dos meses de edad

Two experimental calves were challenged with an enterotoxigenic Escherichia coli strain between 2 and 5 clays old. They had been recovered of the experimental infection. At two months old both calves presented again diarrhoeic syndrome. The clinical signs were similar to those presented in the experimental inoculation. In the microbiological test, Escherichicria coli K99+, STa+ was detected. This results are not coincident with the literature. In general is established that Escherichia coli infection in calves occurs during the first days after birth.    Dos terneros provenientes de un ensayo experimental de desafío con Escherichia coli enteropatógena entre los 2 a 5 días de vida y que se habían recuperado de la infección inducida, presentaron a los 2 meses de edad el síndrome diarreico, sin mediar esta vez una inoculación experimental. Los signos clínicos fueron similares a los manifestados en la inoculación experimental. En los ensayos microbiológicos se detectó la presencia de Escherichia coli K99+, STa+. El desarrollo de este cuadro no coincide con lo expuesto en la literatura que, en general, establece que la infección por E. coli en terneros sólo se produce en los primeros días de vida, siendo posteriormente resistentes. &nbsp

Escherichia coli enterotoxigénica en síndrome diarreico en bovinos de dos meses de edad

Two experimental calves were challenged with an enterotoxigenic Escherichia coli strain between 2 and 5 clays old. They had been recovered of the experimental infection. At two months old both calves presented again diarrhoeic syndrome. The clinical signs were similar to those presented in the experimental inoculation. In the microbiological test, Escherichicria coli K99+, STa+ was detected. This results are not coincident with the literature. In general is established that Escherichia coli infection in calves occurs during the first days after birth.    Dos terneros provenientes de un ensayo experimental de desafío con Escherichia coli enteropatógena entre los 2 a 5 días de vida y que se habían recuperado de la infección inducida, presentaron a los 2 meses de edad el síndrome diarreico, sin mediar esta vez una inoculación experimental. Los signos clínicos fueron similares a los manifestados en la inoculación experimental. En los ensayos microbiológicos se detectó la presencia de Escherichia coli K99+, STa+. El desarrollo de este cuadro no coincide con lo expuesto en la literatura que, en general, establece que la infección por E. coli en terneros sólo se produce en los primeros días de vida, siendo posteriormente resistentes. &nbsp

Variaciones hemáticas post inoculación de una cepa de campo Escherichia coli K99+, en terneros

De un total de 19 terneros Holsteins Friesian, a 15 de ellos privados de calostro se les produjo experimentalmente una colibacilosis entérica, con el objeto de analizar el comportamiento de algunas variables hemáticas.Estos animales se distribuyeron aleatoriamente en dos grupos, los que fueron inoculados vía oral, con una cepa de campo de Escherichia culi K99+ (6 x 108 u.f.c.). Un grupo (10 animales) fue tratado en base a Gentamicina, suero poliiónico, glucosado entre la hora y las 6 hrs., post inóculo (P.I.). Otro grupo de cinco animales no recibió tratamiento. Los cinco animales restantes ingirieron calostro sirviendo como fuente de referencia para los componentes sanguíneos estudiados. Las inoculaciones se efectuaron entre las 39,6 ± 16,5 y las 40,8 ± 17,9 hrs. de vida, presentándose la diarrea entre las 5,0 ± 2,4 y las 6,3 ± 0,5 hrs. P.I.Sólo se observó mortalidad en el grupo no tratado. La serie roja y las proteínas totales se incrementaron en todos los animales P.I. Los leucocitos totales y neutrófilos disminuyeron entre 24 a 48 P.I y se presentó una desviación a la izquierda regular entre las 8 a 24 hrs. P.I.El sodio de 142,3 ± 11,8 mEq/L descendió a 125,7 ± 0,3 mEq/L a las 48 hrs. P.I. El potasio se incrementa desde 5,1 ± 2,5 a 7,0 ± 1,8 mEq/L a las 72 hrs. P.I. Los cloruros variaron desde 64,3 ± 25,5 a 75,3 ± 4,6 mEq/L al mismo tiempo P.I. en el grupo no tratado, a diferencia de los tratados donde los electrolitos fueron similares a los controles no inoculados. La osmolaridad presentó gran variabilidad no significativa P.I., el bicarbonato descendió desde 38,5 mmol/L en el primer día de vida hasta 31,2 y 30,5 mmol/L a las 8 y 20 hrs P.I. Se discuten las variaciones de los valores determinados en base al cuadro inducido y sus proyecciones clínicas.Palabras clave: Escherichia coli K99+; diarrea experimental; terneros.AbstractFifteen colostrum-deprived calves were given (per os) 6 x 108 cfu, E. coli native strairr. Other five calves with colostrurn not inoculated were used as control groulp. Ten inoculated animals were treated tirith GentarnicineR and poliionic fluid between one and six. hours after diarrhea presentation. The diarrhea presentation ocurred 5 ± 2.3 h. following bacterial inoculation. All five colostrum-deprived calves without treatment died.Total proteicas and erytrocytes raised in all inocrdated animals. The total leucocytes count and neutrophils decreased between 6 and 24 hrs. P.l. The sodiun 142 ± 11.8 mEgIL descended to 125.7 ± 0.3 in 48 lars. P.l., the chloremia changed fronz 64.3 ± 2.5 to 75.3 ± 4.6 mEq/L ira the sanie period. The osmorality showed no differences Bicarbonates levels diminished from 38.5 m mol/L to 31,2 in mol/L in 8 hrs. P.I.Key words: Calves diarrhea: Escherichia coli K99+; experimental diarrhea

Inoculación experimental de Escherichia Coli K99+ST+ en terneros. Estudio clínico y anátomo patológico

Se reprodujo experimentalmente la colibacilocis en terneros recién nacidos, con el objetivo de determinar la respuesta clínica y anátomo patológica. Se utilizaron 19 animales Holstein Friesian asignados aleatoriamente en 4 grupos; el grupo 1 constituido por terneros que ingirieron calostro, los 3 restantes constituidos por individuos privados de calostro. En la inoculación se empleó una cepa de Escherichia coli K99+ enterotoxigénica, en una dosis de 100 ml de inóculo vía oral, con una concentración de 6 x 108 unidades formadoras de colonias (UFC) por ml.Los grupos II y III, una vez aparecida la signología fueron tratados con gentamicina, suero poliónico y suero glucosado al 5%. Los individuos tratados respondieron favorablemente a los fármacos administrados. Las muertes atribuidas al cuadro experimental sólo se presentaron en el grupo IV, no tratados. Las lesiones macro y microscópicas son coincidentes con las establecidas en la literatura.Palabras claves: E. coli, diarrea, terneros.AbstractColibacillosis was experimentaly produced in newlyborn calves ira orden to determine the clinical and anatomical pathologic response. Nineteen Holstein Friesian calves were randomly assigned to four groups: group I consisted of calves which ingested colostrum and the other 3 groups consisted of colostrum-deprived calves. An enterotoxigenic strain of Escherichia coli K99+ was employed for the inoculation, in a doce of 100 ml of inoculum per os of an inoculum containing 6 x 108 colony-forming units per ml.Groups II and III were treated as soora as clinical signs appeared, with gentamicin, electrolytes and 5% glucose solution. Treated calves responded favorably to the drugs adrninistered. Deaths atributed to exper-mentally-induced disease were only obserbed in Group IV, untreated calves. The macro and miscroscopy lesions were similar to those described in the literature.Key Words: E. coli, calves, diarrhea