• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.24 no.2 s.173
• /
• pp.329-337
• /
• 2000

An investigation has been performed to develop an analysis tool based on a nonlinear beam theory, which can be used to predict the long-term behavior of an artificial hip joint. The nonlinear behav ior of the femur arise from the coupled dependence of the bone density and the mechanical properties on each other. The beam theory together with its numerical algorithm is developed to take into account the nonlinear bone remodeling process of the femur that is long enough to be assumed as a beam. A piecewise linear curve for the bone remodeling rate is used in the bone remodeling theory and the surface area density of bone is modeled as the third order polynomial function of bone density. At each section of the beam, a constant curvature is assumed and the longitudinal strains are also assumed to vary linearly across the section. The Newton-Rhapson iteration method is used to solve the nonlinear equations for each cross section of the bone and a backward method is used to march along the time. The density and the remodeling signal ar, calculated along with time for the various time steps, and the developed beam theory has been verified by comparing with the results of finite element analysis of a remodeling bone with an artificial hip joint of titanium prosthesis subjected to uni-axial loads and pure bending moment. It is concluded that the developed beam theory can be used to predict the long-term behavior of the femur and thus to design the artificial hip prosthesis.

• Journal of the Korea Convergence Society
• /
• v.9 no.6
• /
• pp.209-215
• /
• 2018

The college liberal arts mathematics is opened as a required course in science and engineering field, but students with low achievement experience difficulty in learning. Therefore, flip learning, which is well known as an effective teaching method based on self-led and learner, is suggested as an alternative. However, some problems are pointed out in this pedagogy. As an alternative to flip learning, we apply flip PBL classes that apply PBL to flip learning to general math subjects to supplement the problems of existing flip learning classes and increase interest in mathematics I want to know the effectiveness of whether it can be done. In this study, we investigated the educational effectiveness of the comparison study between the experimental group applying flip PBL class and the control group applying the existing flip learning class. First, the experimental group showed higher than the control group by 22 points Second, in the reflection journal analysis, in contrast to the control group, there was a positive effect on the improvement of the interest of the mathematics in the experimental group, It is expected that it will be applied as a teaching method that can complement the learning.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.35 no.3
• /
• pp.556-561
• /
• 2008

Neurofibromatosis is an autosomal dominant disorder caused by a mutation of a tumor supressor gene on the long arm of chromosome 17. There are two types of neurofibromatosis, and development of neurofibroma is one of clinical diagnostic criteria for neurofibromatosis. The clinical signs of neurofibromatosis include as skin lesions, bone deformities, and tumors involving central nervous system. About 25% of neurofibromatosis involves oral neurofibroma. Radiographically, oral neurofibroma is well-defined unilocular radiolucency, which involves mandibular canal, mandibular foramen and mental foramen. When a lesion is small and approachable, complete resection, including 1cm of marginal connective tissue, is feasible. However, there are studies reporting that the recurrence rate after surgical resection is high and frequent recurrence may even increase the risk of malignant transformation. This case reports a patient with neurofibromatosis type I, accompanying oral neurofibroma, who shows a favorable result after surgical resection of the oral lesion.

• Journal of The Korean Association For Science Education
• /
• v.31 no.4
• /
• pp.557-566
• /
• 2011

This study investigated the effect of subject classroom system by examining students' perceptions of science discretion class, which was newly developed as Science Mathematics specialized subject classroom system. Science discretion subject proceeded through inquiry experiments in the subject classroom, applying both block scheduling and divided classes. Surveys were conducted twice in order to find out what the students thought about science discretion subject and subject classroom class. The results have shown that students considered that the teachers have prepared with enhanced enthusiasm and the classes have become more interesting. The satisfaction level for experiment centered subject was very high (84%) and significantly higher in case of science-oriented course students (p<.05) and upper level students (p<.01). In addition, most of the students thought favorably about block scheduling and divided classes.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.34 no.4C
• /
• pp.437-445
• /
• 2009

Node of USN(Ubiquitous Sensor Network) environments uses radio based communication mechanism for a delivering message. Thus the multiple hop flooding is necessary for considering limited power and communicating unknown node long-range. However if there are many unknown nodes located in users' vision, the flooding of the radio base is insufficient alternative. Thus as a flash may be used to find a key in a darkness, a more direct and short range communication system is required. This study shall resolve such question through 2 different steps. First a Two kind of code method that convert Text message to color code shall be suggested. Second a hardware module, which may deliver various LED(light-emitting diode) color signal, shall be developed. The experiment may take place by fixing the entry angle of light and distance by setting a specific element as a standard mean.

• Journal of Engineering Education Research
• /
• v.23 no.1
• /
• pp.10-25
• /
• 2020

This study was conducted to identify the causes of academic weakness and to find the ways to cope with it for the students majoring in science and engineering at the top university in Korea. For this purpose, a questionnaire was conducted for students who experienced academic warning and poor academic performance at A university, and a total of 207 students responded. The results were divided into two groups majoring in science and engineering or not and the characteristics and differences of each group were analyzed. In addition, in-depth interviews were conducted with five students who had experienced academic warning and poor academic performance. As a result, the group majoring in science and engineering had a relatively low level of difficulty in forming interpersonal relationships and relatively high degree of participation of activities in their departments. The group majoring in science and engineering have a tendency to choose careers that are connected with their majors, and therefore, their response was relatively low due to lack of career goals. However, the group majoring in science and engineering had difficulty in academic performance due to the difference in basic courses and the level of recognition about self-learning strategy needed for university study was relatively low compared with the group majoring in non-science and engineering. When they experienced academic problems, they said that their interest, support, and positive feedback from professors helped them recover their motivation and continue their studies. Through these results, it was confirmed that intervention and support are needed considering the academic situation and characteristics of the students majoring in science and engineering.

• Journal of Engineering Education Research
• /
• v.13 no.6
• /
• pp.87-98
• /
• 2010

In this research, we analyzed the effects of the independent research program on the educational experience of undergraduate students in a research-centered university setting. The independent research program was developed to provide undergraduate students with opportunities to engage in self(student)-initiated, self-regulated and self-responsible research projects. We hypothesized that outcomes of the program would be utilized as a baseline information in formulating the strategies for improvement of the undergraduate curriculum. Eighty three undergraduate students participated in the program during the period of 2003-2009. In order to evaluate results of the program, we carried out survey and in-depth interviews with the participants. According to the participant reports, the independent research program has helped them to develop self-managed research abilities and problem solving skills. They also indicate that the program has offered them the opportunities to survey the various major fields transcending different domains, so as to help them to contemplate on their future career choices. We suggest that such information may provide an essential guideline for developing an innovative undergraduate curriculum.

• Imaging Science in Dentistry
• /
• v.39 no.2
• /
• pp.81-87
• /
• 2009

Purpose: To evaluate the anteroposterior length and buccal angle of the anterior loop, and the size and location of the mental foramen using cone beam computed tomography (CBCT). Materials and Methods: 100 CBCT images from 87 adults (43 males and 44 females) ranging in age from 20 to 73 years (average 50 years) with edentulous ridge of the mandibular premolar region were obtained. Axial, sagittal, coronal images were reconstructed from Dental and Block Images of CBCT. The anteroposterior length, shape and buccal angle of the anterior loop, and the size and location of the mental foramen were calculated from reconstructed images of axial, sagittal and coronal CBCT. Results: The anteroposterior length and buccal angle of the mental canal was 4.0${\pm}$1.2mm, 37.8${\pm}$11.60$^{\circ}$respectively. The loop type with straight course was the most common shape of the mental canal. The location of the mental foramen below the apex of the lower second premolar (78%) was the most common. The maximum size of the mental foramen was 4.6${\pm}$1.0 mm in width and 3.0${\pm}$0.6 mm in height. The inner size of the mental canal was 2.6${\pm}$0.6 mm in width and 2.1 mm${\pm}$0.4 mm in height. Conclusion: CBCT is useful to evaluate the anterior loop and mental foramen of the mandibular canal. Safe guideline of 4 mm from the most anterior point of the mental foramen is recommended for implant and surgical treatment. (Korean J Oral Maxillofac Radiol 2009; 39: 81-7)

• 대학교육
• /
• s.163
• /
• pp.13-17
• /
• 2010

최근 들어 미국, 유럽, 인도 등과의 FTA체결 등을 통해서 대한민국의 경제시장이 날로 증가해가고 있으며, 이제 해외와의 협력은 우리에게 선택이 아닌 필수가 되어가고 있다. 얼마 전 한 신문에 국내기업과 일본기업의 경쟁력을 비교하는 흥미로운 기사가 소개되었다. 이 신문에서는 국내기업들이 한정된 내수시장을 극복하기 위해 해외로 적극적으로 진출하였기 때문에 우수한 경쟁력을 확보하였으며, 반면 일본기업의 경우 안정된 내수시장이 오히려 해외로 진출할 기회를 가로막아 스스로와 경쟁력을 감퇴시켰다고 분석하였다. 이러한 사례는 우리 대학들에 시사하는 바가 크다. 우리 대학들의 주요한 연구성과라 할 수 있는 논문의 경우 이공계를 보면 대다수의 논문이 이미 해외의 각종 유명 학술지에 게재되고 있다. 특히 우수한 연구성과의 산물이라 할 수 있는 SCI논문의 경우 2008년기준으로 경제규모에 걸맞은 세계 12위에 랭크되어 있다. 또한 특허의 경우 이미 세계 4위의 출원대국이다. 이러한 성과로 인하여 국제공개어에 한글이 채택되는 성과까지 거두고 있는 상황이다. 또한 MB정부가 들어서면서 매년 R&D연구비를 10%이상 증가시킬 계획에 있으며, 이러한 노력을 통해 연구성과물의 수준도 향상되어 SCIENCE, CELL, NATURE등의 저명학술지 게재가 늘고 있는 등 연구성과가 세계적인 수준으로 접근해가고 있다. 반면에 이러한 성과에도 불구하고 아직 대다수 대학들의 글로벌 산학협력은 미비한 수준이다. 교육분야에 대한 글로벌화는 최근 들어 많은 변화가 이루어지고 있지만, 산학협력부분에 대한 글로벌화는 활성화 되지 못한 것이 현실이다. 그러나 앞으로 해외와의 산학협력은 대학과 연구자에게 선택이 아닌 필수가 될 전망이다. 정부에서는 현재 국제협력 분야의 R&D연구비를 급증시키고 있으며, 우리나라의 기업이 해외로 활발하게 진출하는 상황에서 이제 연구수준도 국내가 아닌 해외에서도 인정받을 수 있는 수준을 요구 받고 있다. 이와 같이 급변하는 상황에서 이제 해외와의 산학협력은 대학과 연구자들에게 새로운 도전이며, 경쟁력을 업그레이드 할 수 있는 기회로 다가오고 있다. 이에 최근 한양대학교의 해외와 기술이전, 사업화, 공동연구, R&D센터유치와 관련된 산학협력 사례 소개를 통해 우리나라 대학의 산학협력을 업그레이드하는 방향을 모색해 보고자 한다.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.17 no.1
• /
• pp.518-525
• /
• 2016

This study examined the relationships and characteristics between generic skills and individual variables. The data from 187 students at a Korean university that participated in the Assessment of Higher Education Learning Outcomes (AHELO) feasibility study were utilized. The results indicated that there were no differences in generic skills according to gender, age, and grade point average (GPA). The field of study was the only variable showing a statistically significant difference in generic skills among the three groups. As a result of cluster analysis, four groups were formed based on the characteristics of generic skills. No differences in generic skills were observed among the four groups according to gender, age, and field of study. On the other hand, there was a statistically significant difference in generic skills among the four groups according to the GPA.