Stability of nonlinear teleoperators using PD controllers without velocity measurements

This paper presents two Proportional-Derivative (PD) like controllers for nonlinear bilateral teleoperation systems. Compared to previous controllers of this kind, these schemes do not make use of velocity measurements. Under the assumptions that the human operator and the environment define passive maps from velocity to force, both controllers can ensure boundedness of velocities and position error. Moreover, in the case that the human and environment forces are zero, the controllers ensure velocity and position synchronization. Furthermore, the paper also presents a generalization to the case of teleoperation of networks of multiple robots. Simulations and real experiments, comparing the performance on free motion and interacting with a stiff wall, support the performance of the reported schemes. The experiments have been performed using two 3-degree-of-freedom nonlinear manipulators.     

Social Status Profiles Among First Grade Children

The focus of our study is social status among first graders. In particular, we will consider the relationship between acceptance and rejection, and how these are connected to three social behavioral traits: bullying, victimization, and social withdrawal. The data set is from peer nominations of 748 children from 49 classrooms in the southwest of Finland, collected by interviews. A Social Network Analysis technique was used to analyze the data. The results indicated a negative correlation between acceptance and rejection, bullying, and social withdrawal, but did not correlate victimization. Positive correlations, however, were observed between rejection and all social behavioral traits. Based on cluster analysis, the first graders can be divided into Liked Children (N?=?447), Popular Bullies (N?=?68), Unpopular Bullies (N?=?28), Marginalized Children (N?=?135) and High Risk Children (N?=?21). All Unpopular Bullies and almost all High Risk children were boys. Boys were also nominated more often than girls as Popular Bullies, whilst girls were more often reported as marginalized or as Liked Children.     

The level of awareness and understanding of copyright laws and policies among academic librarians in Ghana

Awareness and understanding of copyright laws are critical in the proper administration of copyright in academic libraries. Data from 38 library staff and 4 head librarians was used in a sequential explanatory mixed methods approach to assess the level of awareness and understanding of copyright laws among library staff with regards to balancing user rights with rightsholder rights in academic libraries in Ghana. The data was collected using questionnaires and qualitative interviews. Though awareness of all the copyright laws, which was not influenced by the educational status of staff was high, the level of understanding was lower. Work experience, schedule of work and current position of staff significantly influenced the level of understanding. The generally moderate level of understanding of copyright laws for library staff; particularly for fair use and creative commons licensing, is a worrying development for copyright administration in academic libraries in Ghana.     

Project DyAdd: Implicit learning in adult dyslexia and ADHD

In this study of the project DyAdd, implicit learning was investigated through two paradigms in adults (18–55 years) with dyslexia (n?=?36) or with attention deficit/hyperactivity disorder (ADHD, n?=?22) and in controls (n?=?35). In the serial reaction time (SRT) task, there were no group differences in learning. However, those with ADHD exhibited faster RTs compared to other groups. In the artificial grammar learning (AGL) task, the groups did not differ from each other in their learning (i.e., grammaticality accuracy or similarity choices). Further, all three groups were sensitive to fragment overlap between learning and test-phase items (i.e., similarity choices were above chance). Grammaticality performance of control participants was above chance, but that of participants with dyslexia and participants with ADHD failed to differ from chance, indicating impaired grammaticality learning in these groups. While the main indices of AGL performance, grammaticality accuracy and similarity choices did not correlate with the neuropsychological variables that reflected dyslexia-related (phonological processing, reading, spelling, arithmetic) or ADHD-related characteristics (executive functions, attention), or intelligence, the explicit knowledge for the AGL grammar (i.e., ability to freely generate grammatical strings) correlated positively with the variables of phonological processing and reading. Further, SRT reaction times correlated positively with full scale intelligence quotient (FIQ). We conclude that, in AGL, learning difficulties of the underlying rule structure (as measured by grammaticality) are associated with dyslexia and ADHD. However, learning in AGL is not related to the defining neuropsychological features of dyslexia or ADHD. Instead, the resulting explicit knowledge relates to characteristics of dyslexia.     

Health-Seeking Preferences of Elderly Filipinos in the Community via Conjoint Analysis

Health-seeking encompasses the activities individuals perform in order to restore wellness when they perceive themselves as ill. Alarmingly, it is apparent that there is a decrease in frequency of health-seeking as one ages. While there have been numerous studies about elderly health-seeking behavior across the globe, the need to know about their preferences remains a research imperative, hence this conjoint analysis investigation. The objective of this study is to identify the health-seeking preferences of a select group of Filipino elderly in the community. To measure preferences for health-seeking, a conjoint analysis survey of 304 Filipino elderly aged 60 years and above was conducted from June to July 2012 using the balanced incomplete block design. Results indicate that the most important attribute in terms of health-seeking behavior is the physician's experience. Elderly clients tend to seek health care from expert private practitioners who provide full information regarding illness and charge professional fees of less than 500 pesos (8–9 British pounds or 12–13 U.S. dollars). Results suggest that there are factors that may impede or promote health care seeking in elderly clients, of which physicians’ experience is deemed most important. These preferences, if integrated into the current practice, can help health care practitioners in improving the quality of care provided.     

Electronic Document Delivery: The Ibadan University Library Experience

New information communication technologies, such as the Internet and electronic publishing, not only enhance the range of publications that libraries can provide for their users but also increase the speed with which such requests can be met. This article describes the development of electronic document delivery (EDD) at the Kenneth Dike Library at the University of Ibadan, Nigeria. A successful EDD program depends upon good intranet and Internet network systems, document availability, user awareness and training, and ease of use. The major challenge to this service is inconsistent power supply, which the university is addressing with the aid of a grant from the MacArthur Foundation for backup electric generators and a university solar energy project. It is hoped that this will assure better and more reliable power service in support of EDD in future. New information delivery regulations and laws guiding adequate service will also emerge but must be properly applied for effective and positive results.     

Static and animated presentations in learning dynamic mechanical systems

In two experiments, we investigated how learners comprehend the functioning of a three-pulley system from a presentation on a computer screen. In the first experiment (N = 62) we tested the effect of static vs. animated presentations on comprehension. In the second experiment (N = 45), we tested the effect of user-control of an animated presentation on comprehension. In both experiments the participants were university students. Comprehension was measured with a test including three comprehension indicators. The first experiment indicated that an animation as well as integrated sequential static frames enhanced comprehension. The second experiment showed that a controllable animation did not have a powerful effect on comprehension, except for learners with low spatial and mechanical reasoning abilities.     

Pre-service teachers’ beliefs and knowledge about multiculturalism

The present study examined pre-service teachers’ knowledge of issues related to multiculturalism and diversity before and after taking a multicultural education course. Data from 38 degree students in an urban university in the southwest of Finland were analysed using a mixed method approach. The results indicate that pre-service teachers’ knowledge levels increased with respect to diversity and multicultural education after taking the course. In addition, pre-service teachers felt more competent and prepared to teach students with diverse backgrounds after the exposure. The implications of the findings for teacher education programmes and teacher educators are discussed.