Modeling and control of a piezoelectric actuator driven system with asymmetric hysteresis

This study describes the high-precision positioning control of a system with asymmetric hysteresis. A switching system concept is adopted to describe the Preisach-type hysteresis, and a systematic modeling procedure is established to obtain the parameters of the system. A piezoelectric actuator system driven by a voltage amplifier is used to verify the modeling accuracy. A control structure, comprising a feedforward controller and a PD-type feedback controller, is used to realize the high-precision positioning control of the piezoelectric actuator driven stage. To enhance tracking control, a high-frequency modified term is incorporated into the hysteresis model. The experimental results confirm that the addition of this modified term reduces the tracking error and prevents the controlling energy from being saturated.     

Reconsidering human performance technology

This article discusses three perceived challenges in the field of human performance technology: a missing link from training to performance, limitations in gap analysis and cause analysis, and a lack of attention to business and organization performance. It then provides possible alternatives for each issue, such as instructional system development frameworks for organizational learning, a soft performance technology framework, and a proposed framework for four levels of performance.     

Satisfying psychological needs on the high seas: explaining increases self-esteem following an Adventure Education Programme

A number of recent studies have revealed that taking part in a sail-training-based Adventure Education Programme elevates youths’ self-esteem. Across two studies, we sought to examine the extent to which youths’ sense of belonging contributed to this increase in self-esteem. Study 1 revealed that participants who completed the voyage showed an increase in self-esteem from the first to the last day of the voyage. Partial correlation revealed that group belonging made a unique contribution to this change. Study 2 replicated Study 1 and, further, demonstrated that the relationship between group belonging and self-esteem was not a function of self-efficacy or group esteem. Such findings suggest that an important contributing factor to the benefits of sail-training interventions is their potential to satisfy psychological needs, in this case the need to belong.     

A critical look into the discourse of educational neutrality: the crisis of democratic education in South Korea

Asia Pacific Education Review - This paper presents an analysis of the ways in which the concept of educational neutrality is used in South Korea. It focuses in particular on the discursive use of...     

Two‐dimensional sectioned images and three‐dimensional surface models for learning the anatomy of the female pelvis

In the Visible Korean project, serially sectioned images of the pelvis were made from a female cadaver. Outlines of significant structures in the sectioned images were drawn and stacked to build surface models. To improve the accessibility and informational content of these data, a five‐step process was designed and implemented. First, 154 pelvic structures were outlined with additional surface reconstruction to prepare the image data. Second, the sectioned and outlined images (in a browsing software) as well as the surface models (in a PDF file) were placed on the Visible Korean homepage in a readily‐accessible format. Third, all image data were visualized with interactive elements to stimulate creative learning. Fourth, two‐dimensional (2D) images and three‐dimensional (3D) models were superimposed on one another to provide context and spatial information for students viewing these data. Fifth, images were designed such that structure names would be shown when the mouse pointer hovered over the 2D images or the 3D models. The state‐of‐the‐art sectioned images, outlined images, and surface models, arranged and systematized as described in this study, will aid students in understanding the anatomy of female pelvis. The graphic data accompanied by corresponding magnetic resonance images and computed tomographs are expected to promote the production of 3D simulators for clinical practice. Anat Sci Educ 6: 316–323. © 2013 American Association of Anatomists.     

Correction to: LGB identity and career decision-making self-efficacy among sexual minority college students

International Journal for Educational and Vocational Guidance - In the original article published, the first author’s affiliation is incorrect. The correct affiliation of the author Hansori...     

Development of PCK for novice and experienced university physics instructors: a case study

The current study assessed and compared university students' perceptions' of a novice and an experienced physics instructor's Pedagogical Content Knowledge (PCK). Two college physics instructors and 116 students voluntarily participated in this study. The research model comprised three workshops, mid-term and final evaluations and instructor interviews. The results showed that each instructor's PCK performance in four categories was slightly improved, though the difference was not statistically significant and only the category of Instructional Representation and Strategies (IRS) was found to be statistically different by students' evaluations of their instructor's PCK. The experienced instructor emphasized life examples and experiments, whereas, the novice instructor emphasized explanations and quizzes. Furthermore, the PCK questionnaire provided university instructors with adequate information so the instructors could receive students' feedback as available sources to reflect on their teaching to improve their quality of teaching. Research implications of this study are provided along with suggestions for future research.     

Exploratory analysis of decentralized governance and its implications for the equity of early childhood education services in four countries of Europe and Central Asia

We conducted a qualitative study in four countries of the Europe and Central Asia (ECA) region and explored the Early Childhood Education (ECE) policy landscape with an emphasis on the challenges and opportunities decentralization has presented for the provision of services. We content-analyzed ECE policies and documents to map national approaches to ECE. Key informant interviews were conducted to assess the implementation of decentralized ECE governance. An analytical framework that combined core constructs of ECE systems and key domains of decentralization (autonomy, institutional capacity and accountability) was developed and applied. Our analysis points to four overarching processes that contribute to the perpetuation and possible increase of inequitable ECE including (1) sparse mechanisms for participatory and autonomous policy formulation, with few systematic efforts to strengthen local institutional capacities; (2) fragmented policy approaches to promote the assessment and strengthening of quality at scale; (3) funding frameworks and financing schemes that tend to benefit enrolment in contexts of higher levels of economic development; and (4) few mechanisms for coordination to ensure operational coherence across the ECE sector.