• 한국과학교육학회지
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• 제28권6호
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• pp.633-640
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• 2008

이 연구에서는 불일치 사례에 대한 학생들의 생각을 확인하기 위한 방안으로서 과학 실험 보고서의 활용가능성에 대해 조사했다. 과학 실험 보고서는 이 연구에서 개발되었으며, 불일치 사례에 대한 학생들의 반응과 관련된 정보를 수집하는 데 사용되었다. 분석은 기체의 용해도와 연소, 전기전도도에 대한 총 839개의 실험 보고서를 대상으로 했다. 실험 보고서에 나타난 학생들의 반응은 거부, 재해석, 배제, 판단불가, 주변이론 변화, 이론 변화, 과학적 개념 유지, 퇴행적 이론변화의 8가지 유형으로 분류되었다. 또한, 재해석과 이론 변화는 몇 개의 하위 유형으로 세분화되었다. 이 연구에서 나타난 학생들의 반응 특징들을 선행연구에서와 비교하여 논의했다.

• 대한교통학회지
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• 제27권4호
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• pp.103-113
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• 2009

교통사고 발생시 119구급대의 신속한 사고현장 도착이 사고심도 감소에 가장 중요한 역할을 한다. 교통사고가 발생하여 부상자가 심정지후 4분이 경과하면 뇌손상이 시작되고 10분이 경과하면 사망할 가능성이 높은 것으로 조사되고 있다. 이에 따라 119구급대의 설치 고려시 교통사고 발생지역까지 통행시간을 고려하여 위치를 결정할 필요가 있다. 본 논문에서는 119구급대의 위치를 결정하는 방안에 대해서 기존 location theory를 검토하여 SCLM과 minisum location theory를 상호활용하는 방안을 모색하였다. 또한 기존 minisum location theory를 적용할 경우 최대통행시간($\lambda$)보다 통행 시간이 증가하는 경우가 발생할수 있는 문제점을 개선한 수정 minisum location theory를 제안한다. 수정 minisum location theory를 적용할 경우 모든 수요를 최대거리($\lambda$)내에 도착하면서 수요량과 통행시간에 대해서 최적화된 119구급대의 위치를 알 수 있다.

• 제어로봇시스템학회논문지
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• 제19권2호
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• pp.107-112
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• 2013

In this paper, we discuss a 3-dimensional localization sensor node using EM waves (Electromagnetic waves) with RSSI (Received Signal Strength Indicator). Generally EM waves cannot be used in underwater environment, because the signal is highly attenuated by the water medium according to the distance. Although the signal quickly reduces in underwater, the reducing tendency is very clear and uniform. Hence EM waves have possibility as underwater distance sensors. The authors have verified the possibility by theory and several experiments, and developed calibration methods in case of linear and planer environment. For 3-dimensional localization in underwater, it must be known antenna's radiation pattern property in electric plane(called E-plane). In this paper, we proceed experiments to verify attenuation tendency with z axis movement, PLF (Polarization Loss Factor) and ILF (Inclination Loss Factor) with its theoretical approach.

• 한국수학교육학회지시리즈A:수학교육
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• 제37권1호
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• pp.115-138
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• 1998

We seek the possibility of introduction of Fractals to the high school math. curriculum through identifying Fractals teaching programs appropriate for the scopes and sequences in math. education for the high school students. We presented the contents of Fractal theory suitable for the high school students. The following subjects were chosen to be introduced; self-similarity, Fractal dimension, Cantor set, Sierpinsky triangle, Sierpinsky carpel Koch curve, Koch island, perimeter estimate of rugged profiles drawn on paper, and chaos game. We developed the working papers and the criteria for appraisal. Each working paper focuses on the activities in which students can solve the given problems, understanding the characteristics and ideas of Fractals. The working papers were given to the second year students who take science course, and the degree of achievements were analyzed based on the appraisal criteria. The results show that it is possible to introduce Fractals to the high school students.

• 수산해양기술연구
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• 제35권1호
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• pp.50-53
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• 1999

In this paper, the mechanical movement of lip seal-ring which plays the most important function in stern-tube sealing system and the possibility of leakage caused by pressure fluctuation are studied by theory and experiment. By the finite element method for axial symmetry object which receives the torsional bending load, the displacement and stress analysis of the seal-rings are executed for products of several representative manufacturers of seal-rings, and also the possibility of crack occurance are checked by theoretical analysis. A sample seal-ring id designed and manufactured using the program of displacement and stress analysis developed in this study and made an experimental apparatus to test the sampling seal-ring. The sampling seal-ring functioned excellently, but it had its durability and this problem may be solved by using the Viton instead of NBR.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1998년도 가을 학술발표회 논문집
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• pp.61-68
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• 1998

It has become important to evaluate the qualitive reliability and condition assessment of existing structural systems in order to establish a rational program for repair and maintenance. Since most of if existing structural system may suffer from defect corrosion and damage, it is necessary to account for their effects in fuzzy reliability analysis, In this paper, an attempt is made to develope a reliability analysis for damaged structural systems using failure possibility theory. Damage state is specified in terms of linguistic valiables using natural language information and numerical information, which are defined by fuzzy sets. Using a subjective condition index of failure possibility and information of the damage state is introduced into the calculation of failure probability. The subjective condition index of quantitative and qualitative analysis method is newly proposed based on the fuzzy set operations, namely logical product, drastic product, logical sum and drastic sum

• 한국실내디자인학회:학술대회논문집
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• 한국실내디자인학회 2001년도 춘계학술발표대회 논문집
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• pp.64-68
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• 2001

As Dutch structuralism discovered a possibility that can improve the problem of modem architecture through study on non-western area. Dutch structuralism had tremendous impact on Philosophy, psychology, art history and the style of a dress and many other cultural trend. In architecture, Aldo van Eyck embodied that theory and succeeded to Herman Hertzberger and Piet Blom. As result Structuralism related with architecture has dealt with the participation and domain of residents, namely public domain and private domain, the approach property of public space, middle domain which shows the harmony between public domain and private one, and the structuralism discovered that each element of public space and private space has been developed as an architectural type that makes a group by repetitive arrangement and it found out a possibility that can make up problems overlooked in modem architecture through development and change.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 하계학술대회 논문집 B
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• pp.720-725
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• 1995

The most important problems which should be considered in designing servo controllers are resonance effects and nonlinear friction. These problems exist in almost all the servo systems, especially for the robotic maniplators and numerical control systems and cause difficulties in designing controllers. In this paper, controller design procedure which employs $H_{\infty}$ control theory is proposed for the servo systems with these problems. Sometimes, for these systems, there is a possibility of limit cycles due to the interation between the nonlinear friction and integrator. To check the possibility of limit cycles, describing fuction method is used.

• 제어로봇시스템학회논문지
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• 제3권3호
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• pp.227-237
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• 1997

Autonomous Underwater Vehicles(AUVs) have become an important tool for various purposes in subsea: inspection, recovery, construction, etc., and the development of autonomous control system is luglay desirable- thete zffe many problems associated with designing the control system for AUV due to unknown underwater envimn-Tnent, the possibility of subsystem failures, and unpredictable changes in the dynamics of the vehicle. In this paper, an autonomous control system based on the intelligent control theory to enhance operation efficiency of the ALTV is presented. The control system has a hierarchical structure which consists of mission planning level, mission control level, navigation level, and execution level. The performance of the control system is investigated by computer simulation. The results show that the proposed control system can be applied successfully to the AUV in spite of the possibility of failures in the vehicle and the collision hazard in the sea environment.

• Journal of Information Technology Applications and Management
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• 제29권2호
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• pp.17-25
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• 2022

Although the two types of currencies compete, the possibility of a virtual currency price bubble is diagnosed by assuming an economic model with currencies (won, virtual currency) that are intrinsically worthless. The won is supplied by the central bank to achieve the price stability target, while the supply of virtual currency increases by a fixed number. According to the basic price theory equation, as a simple proposition, cryptocurrency prices form a Martin Gale process [Schilling and Uhlig, 2019, p.20]. Based on the existing theoretical proposition, we applied the variance ratio verification method [Linton and Smetanina, 2016] and a simple technical chart method for empirical analysis. For the purpose of this study, the possibility of a bubble was empirically analyzed by analyzing the price volatility formed in the Korean virtual currency market over the past year, and brief policy implications for this were presented.