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Factors of Students' Career Choice Related to Science (초.중.고 학생들의 과학 관련 진로 선택 요인)

  • Yoon, Jin
    • Journal of The Korean Association For Science Education
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    • v.22 no.4
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    • pp.906-921
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    • 2002
  • The purpose of this study was to survey the students' career choice related to science. Important factors of career choice were identified through factor analysis. 'Perception of career related to science', 'preference for science learning' and 'participation in science-related activity' were three main factors of science-related career choice. Students' responses to the three main factors were compared according to their career choice, grade and gender using ANOVA. Regression analysis was adopted to find out the relative importance among the three main factors. The subjects were 947 grade 6, 9 and 11 students in Seoul. Numbers of boys and girls in each grade was almost same. The questionnaire was developed to know the factors of students' science-related career choice after preliminary research and literature survey. The ratio of science-related career choice was not high (26%). Students' responses to and the relative importance of the three main factors differed with the grade and gender. From the results, making students have preference for science and giving them more opportunities of science-related activity is more important than making them have positive perception of science-related career. It is required to make a material for science career education considering the differences of age and gender using this study results.

An Inverse Kinematic Analysis of a Binary Robot Manipulator using Genetic Algorithms (유전 알고리즘을 이용한 2진 로봇 머니퓰레이터의 역기구학적 해석)

  • 이인석;류길하
    • Journal of the Korean Society for Precision Engineering
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    • v.17 no.4
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    • pp.203-208
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    • 2000
  • 2진 로봇 머니퓰레이터는 기하학적 형상이 가변트러스 구조로 되어 있으며 조인트의 구동원으로 사용되는 엑츄에이터는 2가지의 변위, 즉 최대 및 최소 변위만으로 동작한다. 따라서 작업영역은 연속적으로 주어지는 일반 로봇 머니퓰레이터와는 달리 유한 개의 위치 벡터의 집합 형태로 나타난다. 기존의 역기구학적 해석방법을 적용하기 어려운 2진 로봇 머니퓰레이터의 불연속적인 특성에 대해 새로운 작업영역과 역기구학 문제를 정의하였다. 유전 알고리즘을 사용하여 새로이 정의된 문제의 역기구학적 해석을 수행하였으며 유전 알고리즘이 2진 로봇 머니퓰레이터의 역기구학적 해석에 있어서 효과적이고 강건한 방법임을 보여주었다.

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Quaternary Sequence with Maximum Autocorrelation of 3 (최대 자기 상관값이 3인 4진 수열)

  • Jang, Ji-Woong;Kim, Sang-Hyo;Lim, Dae-Woon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.2C
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    • pp.158-162
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    • 2009
  • In this paper, we propose a quaternary sequence with good autocorrelation property. New quaternary sequence is generated by using inverse Gray mapping and binary sequence with ideal autocorrelation. And the maximum magnitude of nontrivial correlation value is 3. Proposed quaternary sequence has only one 1 in one period, so called almost binary sequence. Therefore the balance property is not good, but value of its weight function is nearly 0.

Development of Straightness Measurement System for Improving Manufacturing Process Precision (ODN제조 공정 정밀도 향상을 위한 진직도 측정시스템 개발)

  • Kim, Eung Soo
    • Journal of the Microelectronics and Packaging Society
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    • v.26 no.1
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    • pp.17-21
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    • 2019
  • In this paper, a high precision straightness measurement system has been developed at low cost using a visible laser and CMOS image sensor. CMOS image sensor detected optical image and the variation of straightness was calculated by image processing. We have observed that the error of the developed straightness measurement system was 0.9% when a distance of 3m between laser and image sensor. And it can be applied to 3D printer and any other areas.

Design of Random Binary Sequence Generator using the Chaotic Map (혼돈맵을 사용한 난수성 2진 순서발생기의 설계)

  • Park, Kwang-Hyeon;Baek, Seung-Jae
    • The Journal of the Korea Contents Association
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    • v.8 no.7
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    • pp.53-57
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    • 2008
  • The discretized saw-tooth map with the 16-bit finite precision which is one of the 1-dimensional chaotic maps is designed, and the circuit of chaotic binary sequence generator using the discretized saw-tooth map is presented also in this brief. The real implementation of designed chaotic map is accomplished by connecting the input and output lines exactly according to the simplified Boolean functions of output variables obtained from truth table which is discretized. The random binary output sequences generated by mLFSR generator were used for the inputs of descretized saw-tooth map, and, by the descretized map, chaotic binary sequence which has more long period of 16 times minimally is generated as a results.

True Stress-True Strain Curves Obtained by Simulating Tensile Tests Using Finite Element Program (인장시험을 유한요소해석 시뮬레이션하여 진응력-진변형도 곡선을 결정하는 방법)

  • Chu, Seok-Jae
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.35 no.1
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    • pp.25-31
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    • 2011
  • In the tensile test necking occurs at the maximum load point and non-uniform stress state is generated in this section. The equivalent stress becomes quite different from the axial stress as necking proceeds. Methods for obtaining the true stress-true strain curves, by overcoming difficulties due to the necking phenomena, have been developed by many authors. One of the methods based on the finite element analysis simulation is a very promising method. In this paper, general-purpose finite element program is used to simulate the tensile test. A round specimen and a flat specimen prepared from the same steel block are tested and simulated. The true stress-true strain curves are determined without assuming that the material follows Hollomon's law.

On the historical investigation of p-adic invariant q-integral on $\mathbb{Z}_p$ (p-진 q-적분의 변천사에 대한 고찰)

  • Jang, Lee-Chae;Seo, Jong-Jin;Kim, Tae-Kyun
    • Journal for History of Mathematics
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    • v.22 no.4
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    • pp.145-160
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    • 2009
  • In the end of 20th century, the concept of p-adic invariant q-integral was introduced by Taekyun Kim. The p-adic invariant q-integral is the extension of Jackson's q-integral on complex space. It is also considered as the answer of the question whether the ultra non-archimedian integral exists or not. In this paper, we investigate the background of historical mathematics for the p-adic invariant q-integral on $Z_p$ and the trend of the research in this field at present.

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The Characteristics of a Career Counseling Network on Gifted Students of Science and general students (과학 영재와 일반 학생의 진로 상담 네트워크 특성)

  • Chung, Duk-Ho;Park, Seon-Ok;Yoo, Hyo-Hyun
    • Journal of Gifted/Talented Education
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    • v.25 no.1
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    • pp.21-36
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    • 2015
  • The purpose of this study is to examine social influence of the counselors on the network for a career counseling on gifted students of science and general students. This study collected data from 151 gifted students of science and 212 general students. The collected data was analyzed by the social network analysis. The results are as follows: First, we found that mother had the highest centrality indicators and teacher had the lowest centrality indicators on the career counseling network in both groups. And the max-flow indicators from mothers to teachers were the lowest on the career counseling network, on other hand; general students had lower centrality indicators than gifted students of science. Second, father was the most obvious counselor to cover for mother, on the hand, teacher was the worst counselor to cover for mother on the career counseling network. The gifted students group of science had less difficulty to cover for mother than the general students group. While teacher had the highest limits to information exchange on the career counseling network in both groups, mother had the lowest limits. As the result, we can conclude that mother played a key role on the career counseling network in gifted students of science and general students, while teachers was excluded from the career counseling network of students. Therefore, it is necessary to connect systematically parents with teachers for leading effectively students to their career; also government needs to build a career counseling system for this.

Elution Properties of Naringin from Soft Contact Lens Containing Naringin (나린진(naringin)이 함유된 소프트 콘택트렌즈에서 나린진의 용출 특성)

  • Ryu, Geun-Chang;Jun, Jin;Jin, Moon-Seok;Chae, Soo-Chul;Kim, In-Suk
    • Journal of Korean Ophthalmic Optics Society
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    • v.13 no.3
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    • pp.45-50
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    • 2008
  • Purpose: A soft contact lens was manufactured by adding naringin known as natural anti-bacterial material to resin solution. With solution eluted from manufactured contact lens, we examined its optical properties, physical and chemical states of naringin in the polymer, and elution properties. Methods: The soft contact lens with naringin was synthesized by bulk polymerization method. IR spectrum and HPLC were used to define the bonding type of naringin itself in the soft contact lens contained naringin, elution process of naringin to the saline solution, and the amount of naringin solution eluted from the lens with elapsed time. Results: Naringin was continuously eluted with constant concentration from the soft contact lens for about a month and the structure ofnaringin which is eluted was as same as before it was added to resin solution. Any change in optical properties such as transmittance couldn't be found. Bonding state and the structure of naringin in contact lens were explained with IR spectrum and HPLC results. Conclusions: In the contact lens with naringin, naringin remained in the contact lens bonding with weak hydrogen bonding and/or van der Waals force between naringin and polymer. Naringin was continuously eluted from the contact lens contained naringin during about 1 month. Even after 1 month, it showed that the concentration of the naringin eluted was approximately 10 ppm in a day. From the results, adding naringin to the soft contact lens resin is very effective method for manufacturing the soft contact lens which has anti-bacterial function for a period of time.

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Systematic Review in Regard to Career Education for Students Who Major in Physical Education (체육전공 대학생의 진로 교육 방안에 관한 체계적 문헌고찰)

  • Lee, Weon-Il;Lee, Eun-Young;Yi, KyoungJune;Jin, Yeon Kyung
    • 한국체육학회지인문사회과학편
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    • v.58 no.3
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    • pp.241-260
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    • 2019
  • The purpose of this study is to explore effective and practical career plans reflecting demand of the field, in regard to education for university students who major in physical education, as the importance and necessity of career education at a university level are increasing. Systematic literature review (PRISMA) methodology was used for this study. From 38 pieces of literature that were finally selected for this study, research results were put together from three perspectives as follows: 1. 'Factors Related to Students' Decision-Making for Career' which should be considered in career education for physical education majors; 2. Problems of Career Education in the Physical Education Curriculum, and; 3. Improvement Plans. First, it was found that students' decision-making for career is affected by individuals' personal internal factors (i.e., satisfaction with major, self-efficacy, and career barrier) and external factors (i.e., counselling history on career paths, career conditions, and the status of related jobs). Second, the state of career education for physical education majors was found to be insufficient in terms of a lack of career education in the curriculum, a lack of support from major professors, and a lack of support for field experience. Third, improvement plans were suggested from the following perspectives: development of systematic career education curriculum (i.e., fostering leadership, reorganization of curriculum focused on career specialty, and operation of systematic curriculum); provision of an adequate environment for career education (i.e., establishment of infrastructure that links the university to society and collection of information on career paths for physical education majors). Moreover, the necessity to develop career education curriculum in connection with demand of students regarding career, the lack of systematic information on career paths of physical education majors, and the lack of researches on career education for physical education majors were discussed in this study.