• Steel and Composite Structures
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• v.48 no.2
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• pp.191-206
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• 2023

The present research investigates how micromechanical models affect the behavior of Functionally Graded (FG) plates under different boundary conditions. The study employs diverse micromechanical models to assess the effective material properties of a two-phase particle composite featuring a volume fraction of particles that continuously varies throughout the thickness of the plate. Specifically, the research examines the vibrational response of the plate on a Winkler-Pasternak elastic foundation, considering different boundary conditions. To achieve this, the governing differential equations and boundary conditions are derived using Hamilton's principle, which is based on a four-variable shear deformation refined plate theory. Additionally, the Galerkin method is utilized to compute the plate's natural frequencies. The study explores how the plate's natural frequencies are influenced by various micromechanical models, such as Voigt, Reuss, Hashin-Shtrikman bounds, and Tamura, as well as factors such as boundary conditions, elastic foundation parameters, length-to-thickness ratio, and aspect ratio. The research results can provide valuable insights for future analyses of FG plates with different boundaries, utilizing different micromechanical models.

• Proceedings of the Korea Information Processing Society Conference
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• 2022.11a
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• pp.359-361
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• 2022

최근 현대인의 영양불균형이 점점 심화됨에 따라 영양결핍과 비만의 위험도가 점점 증가하고 있다. 이에 따라 건강기능식품에 대한 관심이 증가하여 일반인들의 건강기능식품 소비가 증가하고 있지만, 적정섭취량에 비해 영양소를 과도하게 섭취 중이거나 영양제를 먹지만 정작 필요한 영양소를 섭취하지 못하는 경우가 빈번히 나타나고 있다. 이러한 문제를 해소하고자 본 논문에서는 7 일간 사용자가 섭취한 식단을 기반으로 부족한 영양소를 수치상으로 계산하여 개인 맞춤 영양제를 추천하는 시스템을 제안한다.

• Educational Technology International
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• v.10 no.1
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• pp.1-23
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• 2009

Learners are often posited in a paradoxical situation where they are not fully involved in decision making processes on how to learn, in designing their tools. Cognitive artifacts in e-learning are supposed to effectively support learner-centered e-learning. The purpose of the study is to analyze cases of cognitive artifacts and to inquire those design principles for facilitating the learner-centered e-learning. Four research questions are suggested: First, it will be analyzed the characteristics of learners with respect to design of cognitive artifacts for supporting the learner-centered e-learning. Second, characteristics of four cases to design cognitive artifacts in learner-centered e-learning environment are analyzed. Third, it will be suggested the appropriate design principles of cognitive artifacts to facilitating learner-centered learning in e-learning environment. Four cases of cognitive artifacts design in learner-centered e-learning was identified as follows: Wiki software as cognitive artifacts in computer-supported collaborative learning; 'Play Around Network (PAN)' as cognitive artifact to monitor learning activities in knowledge community; Knowledge Forum System (KFS) as a cognitive artifact in knowledge building; cognitive artifacts in Courses-as-seeds applied meta-design. Five design principles are concluded as follows: Promoting externalization of cognitive artifacts to private media; Helping learners to initiate their learning processes; Encouraging learners to make connections with other learners' knowledge building and their cognitive artifacts; Promoting monitoring of participants' contributions in collaborative knowledge building; Supporting learners to design their cognitive artifacts.

• Journal of Digital Contents Society
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• v.13 no.3
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• pp.393-399
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• 2012

New and creative skills must be developed, and adapted into a lesson, to motivate learners to acquire a second language easily and enjoyment, Multimedia tools which are of interest to learners, such as; smart phones, computers, and notebooks with wireless internet compatability, will provide learners opportunities to study, and do their work practically anywhere and anytime. Recently, podcasts, which are a type of digital media, consisting of a series of audio episodes or video files, subscribed to and downloaded through web syndication, or streamed online to a computer or mobile device, are used to facilitate ESL (English as a Second Language) learning. Development of a variety of teaching methods, using multimedia tools, is needed. There are advantages and disadvantages to using a variety of multimedia tools. The current research aims to study its characteristics and application, in order to maximize their effective use, in English education. The current study suggests a ubiquitous learning environment using multimedia content tools, internet media, video teleconferencing, cyber-learning, and one-to-one videos used in conjunction with, or as a digital textbook for the English lesson. This study also investigates future educational changes, using state-of-the-art equipment for the self-learning experience, and will present a new direction in English education, through a variety of instructional devices and a marginalized class system model.

• Journal of Internet Computing and Services
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• v.13 no.6
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• pp.41-53
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• 2012

Open educational resources(OER) enable the spread of mutual information exchange and provide advantages to both their users and institutions, such as reducing costs, improving content quality, and establishing relationships. The recent research on OER was about their connection to formal education, copyright trends, and corporate e-learning. There have been very few studies, however, on the utilization of OER and on the problems related to their practical use. Thus, this study was conducted for the purposes of analyzing the status of OER usage in education-related institutions and of providing suggestions for institution operation based on the analysis results, to promote the use of OER. A survey was conducted among more than 200 institutions in Asia, and the survey results showed that 'images and visual materials' are the most commonly used materials in Asia, and that the factors barring OER usage in the said region are 'lack of awareness', 'lack of skills', 'the absence of a reward system', and poor cooperation in participation. To promote OER usage, each institution should provide training courses about awareness, utilization skills, and copyrights. There is also a need to provide support for the establishment of reward systems and environments for OER usage. Finally, more active participation is required for inter-agency cooperation in OER sharing.

• Korean Journal of Health Education and Promotion
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• v.19 no.3
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• pp.97-105
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• 2002

This study attempts to develop a program for obesity prevention and management for students in primary, middle, and high school and was carried based on the program development process as suggested by Ewles and Simnett. Data were collected from September 1st to September 30th, 2000. The study method is as follows: 1) Reviewing the present obesity control programs practiced in primary, middle, and high school (196 schools total) in metropolitan, medium-sized, and small cities, 2) Surveying obesity students'(682 students total) perception of the obesity management in their school. 3) Reviewing the annual plan for obesity in primary, middle, and high schools 4) Analyzing the educational data (CD, VIDEO) for obesity The results are as below: I. The media researched related to obesity were mainly CD and video, aimed primarily primary school students and are biased in nature. 2. The results of how to manage obesity in students: the difficulty of obesity education in the primary school, is the arousal of a sense of shame among obese students and the lack of various educational data are the most. In the middle and high schools, a lack of various educational data, and no time or lack of time were prevailing concerns. Paramount in managing obesity is weight control, as answered by majority of primary, middle, and high school students. The major problem of obesity management is the non-cooperation of children. 3. Asked whether the weight controlling aspect of health care class was helpful or not, 51.4% of primary school students, and 71.6% of middle and high school students answered not. The most popular educational method used in health care class is the computer, with a 56.4% approval rating. Most 43.5% of respondents answered that they wanted the content of obesity management program to focus on how to lose weight. Therefore, based on the results, the obesity management program is constructed to the steps of assessment, planning, implementation, and evaluation. Assessment includes administering surveys on health needs among students and their parents and physique tests. Planning includes the set-up of long term and short term educational goal and the establishment of an operation system. Implementation includes education, exercise, behavior modification, and health service programs. Evaluation includes step-by-step evaluations for obesity reduction. After this study is conducted, the following should be further researched: More practical and systematic obesity management programs should be developed for the evaluation results. In addition, it is important to develop an appropriate media for obesity management the primary, middle and high school students.

• Research in Community and Public Health Nursing
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• v.11 no.2
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• pp.577-590
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• 2000

This study is basic research for developing health promotion programs in elementary school and is looking at the effect factor of School nurses perception and school health promotion. This study was conducted with the ACCESS model for school health promotion from WHO. The subjects of this study were 28 elementary school nurses located in the west side of Kung-Nam from the 7th of June to the 30th of June by direct interview. The results of this study are summarized as follows: 1. the score from obesity, dental caries, health counselling, scoliosis, hepatitis B, immunization BCG items are higher in the low grade but showed significant difference in visual disturbance items. 2. the average score of school health promotion perception is 5.04. The list of school health promotion is composed of school health policies(5.39), physical environments (5.38), school health services(5.34), social environments (5.22), personal health skills (4.92), and community relationships(4.64). 3. after an analysis of the perception of school health promotion from school nurses, the relationship between the school health budget and the school health policy and school health service was shown to be significant. 4. after analysis of the effect factor of perception of school health promotion from school nurses, school health policy, school social environment, personal health skills, and school health service were shown to be significant. 5. The factors in school health promotion are the number of classes and students, school budgets, school nurses' final education and age, health education classes per week, and teaching experience. Particularly the school health budget and school nurses of the classes per week are statistically significant. The suggestions of this study are as follows: 1, as a related factor of school health promotion. the generally characteristics of schools and school nurses should be considered for improving the perception of school health promotion. 2, the period of health education for effective school health management and health education should be an on-going program. 3. the scope of school health promotion and perception should be considered for developing health promotion programs. 4. elementary school health promotion programs should be developed and applied to research. 5. computer system programs should be developed for effective school health projects.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.3
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• pp.619-623
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• 2018

This paper aimed to design a computer course teaching-learning strategy for (m-learning?) to be used in a Problem Based Learning (PBL) environment. The research findings were as follows. Firstly, learning contents were provided as educational tools for mobile device usage. The educational contents provided were designed for effective usage on mobile devices, such as smartphones, thereby making mobile devices suitable for use as learning tools. Secondly, learning contents for PBL were provided. PBL problems (for computer engineering courses) were made with the principles of teaching plans. The learning objectives were achieved through the problem-solving progress of the learners and their self-directed and cooperative learnings. Thirdly, learning resources were provided that were easily accessible through smartphones, laptops and PDAs. This study is about the PBL instructional design of creative engineering design subjects, which aims to foster talent. The PBL model developed in this study consists of Analysis, Design, Development, Implementation, and Evaluation. We made a plan for creative engineering design subjects based on PBL, and focused on the process of PBL. This research was able to establish the basis for PBL usage in Engineering Schools and help achieve its ultimate goal of endowing professional intellectuals with creative problem-solving abilities.

• Journal of the Korea Computer Graphics Society
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• v.15 no.3
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• pp.1-9
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• 2009

Traditional computer simulation uses only traditional input and output devices. With the recent emergence of haptic techniques, which can give users kinetic and tactile feedback, the field of computer simulation is diversifying. In particular, as the virtual-reality-based surgical simulation has been recognized as an effective training tool in medical education, the practical virtual simulation of surgery becomes a stimulating new research area. The surgical simulation framework should represent the realistic properties of human organ for the high immersion of a user interaction with a virtual object. The framework should make proper both haptic and visual feedback for high immersed virtual environment. However, one model may not be suitable to simulate both haptic and visual feedback because the perceptive channels of two feedbacks are different from each other and the system requirements are also different. Therefore, we separated two models to simulate haptic and visual feedback independently but at the same time. We propose an adaptive mass-spring method as a multi-modal simulation technique to synchronize those two separated models and present a framework for a dual model of simulation that can realistically simulate the behavior of the soft, pliable human body, along with haptic feedback from the user's interaction.

• Journal of the Microelectronics and Packaging Society
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• v.14 no.3
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• pp.1-6
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• 2007

In this study, the pentacene thin films were prepared by the soluble process, and characterized fur the application of the organic thin film transistor(OTFT) device. To dissolve the pentacene material, two kinds of solvents such as toluene and chloroform were used, and the effects of these solvents on the properties of pentacene thin films coated on ITO/Glass substrate were investigated. Pentacene thin films were prepared by using spin-coating methode and characterized the surface morphology, crystalline and electrical properties. From the AFM measurement, the surface morphology of the pentacene film dissolved with chloroform was improved compared with the one dissolved with toluene solvent. XRD measurement showed that all prepared pentacene film samples were amorphous crystal phases without crystallization of the films. The electrical properties of the pentacene film dissolved with chloroform showed better results than the ones using toluene solvent by hall measurement system. The carrier concentration and the mobility values of pentacene films using chloroform solvent were found to be $-3.225{\times}10^{14}\;cm^{-3}$ and $3.5{\times}10^{-1}\;cm^2{\cdot}V^{-1}{\cdot}S^[-1}$, respectively. The resistivity was about $2.5{\times}10^2\;{\Omega}{\cdot}cm$.