Three dimensional couette flow and heat transfer through a porous medium with variable permeability

This paper reports research on the effects of variations in injection velocity and permeability on the heat transfer and flow through a highly porous medium between two horizontal parallel plates situated at constant distance with constant suction by the upper plate. Due to this type of variation in injection velocity and in permeability the flow becomes three dimensional. The governing equations are solved by adopting complex variable notations to obtain the expressions for the velocity and temperature field. The skin-friction along the main flow direction and rate of heat transfer are discussed with the help of graphs.     

Developing Environmentally Responsible Behaviours Through the Implementation of Argumentation- and Problem-Based Learning Models

Research in Science Education - The purpose of this research is to investigate the effect of using argumentation and problem-based learning approaches on the development of environmentally...     

History Run Wild: The Alternate World of Joan Aiken’s <Emphasis Type="Italic">The Wolves of Willoughby Chase</Emphasis> Series

This article examines the historical fantasy world created by Joan Aiken in the eleven volumes of her Wolves of Willoughby Chase series. In particular it looks at her subversion of historical reality by the creation of an alternative yet recognisable representation of our own world, using a wide range of events, and the remoulding of aspects of language and geography. It also discusses her reasons for writing in this form and explores the character of Dido Twite as heroine and major raison dtre of the series.This revised version was published online in May 2005 with corrections to the article title.     

Expertise Differences in the Comprehension of Visualizations: a Meta-Analysis of Eye-Tracking Research in Professional Domains

This meta-analysis integrates 296 effect sizes reported in eye-tracking research on expertise differences in the comprehension of visualizations. Three theories were evaluated: Ericsson and Kintsch’s (Psychol Rev 102:211–245, 1995) theory of long-term working memory, Haider and Frensch’s (J Exp Psychol Learn Mem Cognit 25:172–190, 1999) information-reduction hypothesis, and the holistic model of image perception of Kundel et al. (Radiology 242:396–402, 2007). Eye movement and performance data were cumulated from 819 experts, 187 intermediates, and 893 novices. In support of the evaluated theories, experts, when compared with non-experts, had shorter fixation durations, more fixations on task-relevant areas, and fewer fixations on task-redundant areas; experts also had longer saccades and shorter times to first fixate relevant information, owing to superiority in parafoveal processing and selective attention allocation. Eye movements, reaction time, and performance accuracy were moderated by characteristics of visualization (dynamics, realism, dimensionality, modality, and text annotation), task (complexity, time-on-task, and task control), and domain (sports, medicine, transportation, other). These findings are discussed in terms of their implications for theories of visual expertise in professional domains and their significance for the design of learning environments.     

Facilitating Understanding of Movements in Dynamic Visualizations: an Embodied Perspective

Learners studying mechanical or technical processes via dynamic visualizations often fail to build an accurate mental representation of the system’s movements. Based on embodied theories of cognition assuming that action, perception, and cognition are closely intertwined, this paper proposes that the learning effectiveness of dynamic visualizations could be enhanced by grounding the movements of the presentation in people’s own bodily experiences during learning. We discuss recent research on embodied cognition and provide specific strategies for how the body can be used to ground movements during the learning process: (1) making or observing gestures, (2) manipulating and interacting with objects, (3) using body metaphors, and (4) using eye movements as retrieval cues. Implications for the design of dynamic visualizations as well as directions for future research are presented.     

Curiosity, interest and engagement in technology-pervasive learning environments: a new research agenda

This paper identifies the need for developing new ways to study curiosity in the context of today’s pervasive technologies and unprecedented information access. Curiosity is defined in this paper in a way which incorporates the concomitant constructs of interest and engagement. A theoretical model for curiosity, interest and engagement in new media technology-pervasive learning environments is advanced, taking into consideration personal, situational and contextual factors as influencing variables. While the path associated with curiosity, interest, and engagement during learning and research has remained essentially the same, how individuals tackle research and information-seeking tasks and factors which sustain such efforts have changed. Learning modalities for promoting this theoretical model are discussed leading to a series of recommendations for future research. This article offers a multi-lens perspective on curiosity and suggests a multi-method research agenda for validating such a perspective.     

Going Outside in Winter: A Qualitative Study of Preschool Dressing Routines

The exploratory study focused on describing typical routines of preparing for winter outdoor play with preschool children and their teachers. Naturalistic observations, interviews and photographs resulted in extensive examples of children’s development in cognitive understanding of winter and winter-related concepts. Observations of teachers and assistants revealed task-oriented perspectives including detailed strategies and planning. Asynchronous communication and directive language were typical of teacher/child communication. Photo analyses confirmed physical skills used by preschoolers to accomplish dressing tasks and extensive curricular changes to indoor environments.     

Mode of communication, perceived level of understanding, and perceived quality of life in youth who are deaf or hard of hearing

Given the important role of parent-youth communication in adolescent well-being and quality of life, we sought to examine the relationship between specific communication variables and youth perceived quality of life in general and as a deaf or hard-of-hearing (DHH) individual. A convenience sample of 230 youth (mean age = 14.1, standard deviation = 2.2; 24% used sign only, 40% speech only, and 36% sign + speech) was surveyed on communication-related issues, generic and DHH-specific quality of life, and depression symptoms. Higher youth perception of their ability to understand parents' communication was significantly correlated with perceived quality of life as well as lower reported depressive symptoms and lower perceived stigma. Youth who use speech as their single mode of communication were more likely to report greater stigma associated with being DHH than youth who used both speech and sign. These findings demonstrate the importance of youths' perceptions of communication with their parents on generic and DHH-specific youth quality of life.     

Effectiveness of Case-Based Learning Instruction on Epistemological Beliefs and Attitudes Toward Chemistry

The purpose of the study was to investigate the effectiveness of case-based learning instruction over traditionally designed chemistry instruction on eleventh grade students’ epistemological beliefs and their attitudes toward chemistry as a school subject. The subjects of this study consisted of 63 eleventh grade students from two intact classes of an urban high school instructed with same teacher. Each teaching method was randomly assigned to one class. The experimental group received case-based learning and the control group received traditional instruction. At the experimental group, life cases were presented with small group format; at the control group, lecturing and discussion was carried out. The results showed that there was a significant difference between the experimental and control group with respect to their epistemological beliefs and attitudes toward chemistry as a school subject in favor of case-based learning method group. Thus, case base learning is helpful for development of students’ epistemological beliefs and attitudes toward chemistry.