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The purpose of this study was to identify the suitable Friction Stir Welding (FSW) parameters that would be used for welding scrapped Al alloy plates. On the experimental side, the study used four Factor Three-Level Full Factorial Design of Experiments (DoE) approach. Some of the input parameters incorporated in the analysis were the applied load, the sliding speed, displacement and weight percentage of Al2O3 reinforcement, and some of the output parameters were the specific wear rate and the coefficient of friction. The above said optimum parameters were established using the Minitab software while the above said experimental results was estimated using multilayer perceptron of the feed forward 4–10–1 network. For the actual test data set in the given experiment, the overall performance of the MLP predictions resulted to an R2. This results to a coefficient of determination (R R2 of 0.98474 and a mean squared error (MSE) of 0. 025075. Therefore the high R values, which are near to 1, show that the actual values mean and the predicted values mean are closely matched.

Thermal energy storage (TES) using phase change materials (PCMs) has been extensively utilized to improve the efficiency of photovoltaic thermal (PVT) systems. High-conductive nanofillers have been an effective method to improve PCM's energy efficiency and thermal management systems. This research modifies high-capacity paraffin using graphene nanosheets (GNS) in small weight fractions of 0.2% and 0.6%. Tween 60 and gum Arabic are added to improve the GNS nanofiller's suspension ability. A higher GNS nanofiller of 0.6 wt% contributes to lower transmittance with higher solar energy absorption. However, GNS/paraffin with Tween 60 results in better thermal stability than gum Arabic surfactant. The improved thermal properties show promising results for TES systems in PVT applications.

Most information in an enterprise is in the form of unstructured data which is usually managed using a document database. One of the key challenges is to define a generalized data model for this unstructured data and any information extracted from it using content enrichment algorithms. It is more challenging to incorporate provenance and temporal capabilities to such data models. Semantic databases use ontologies such as PROV-O to represent their provenance information expressively, and relational databases use for example Slowly Changing Dimensions (SCDs) concepts to represent temporal information. In this paper, we present a document model which has features inspired from Dublin core, PROV-O and temporal methodologies to generalize information extracted from unstructured data using content enrichment algorithms. Provenance information enables comparison of enrichment models, allows reproducibility and facilitates complex filtering on the enriched data. Temporal metadata helps in versioning the document and enables point-intime and history queries conveniently.

Background: Pediatric clinical skills teaching sessions provide an early opportunity for students to be exposed to the medical care of children. This report describes second and third year medical students’ perceptions of and attitudes towards working with children before and after the pediatric clinical skills teaching sessions, and the experiences of those students precepted by pediatricians only compared to those students working with a combination of pediatricians and family physicians. Method: A 13 question survey was voluntarily completed before and after teaching sessions. Written reflective assignments were qualitatively analyzed for key themes. Response rate averaged 68% with class sizes of 84 and 85 students. Results: Students’ perceptions of the care of children were generally very positive. Some differences were found based on gender, phase of study and prior clinical exposure to pediatric care. Pre and post responses were similar, regardless of preceptor specialty. Students with family physician preceptors identified the themes of prevention, health promotion and multidisciplinary care in their reflections. Conclusions: Students had already formed positive attitudes toward the medical care of children and intended to care for children in their future practice. Further research is needed into the effects of pre-clerkship experiences in the care of children on choice of medical specialty.