• 대한수학교육학회지:수학교육학연구
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• 제11권2호
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• pp.385-402
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• 2001

The purpose of this study is to conceptualize 'proof' school mathematics. We based on the assumption the following. (a) There are several different roles of 'proof' : verification, explanation, systematization, discovery, communication (b) Accepted criteria for the validity and rigor of a mathematical 'proof' is decided by negotiation of school mathematics community. (c) There are dynamic relations between mathematical proof and empirical theory. We need to rethink the nature of mathematical proof and give appropriate consideration to the different types of proof related to the cognitive development of the notion of proof. 'proof' in school mathematics should be conceptualized in the broader, psychological sense of justification rather than in the narrow sense of deductive, formal proof 'proof' has not been taught in elementary mathematics, traditionally, Most students have had little exposure to the ideas of proof before the geometry. However, 'proof' cannot simply be taught in a single unit. Rather, proof must be a consistent part of students' mathematical experience in all grades, in all mathematics.

• 대한수학교육학회지:학교수학
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• 제5권4호
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• pp.401-420
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• 2003

증명 학습에 있어서 많은 어려움이 특히, 증명이 도입되는 중학교 기하 단원의 학습에서 야기되고 있으며, 무엇보다도 많은 학생들이 증명의 의미를 이해하지 못하는 것은 간과하기 어려운 문제점이다. 본 고에서는 기하의 역사 발생적 단계에 따른 증명의 의미 지도가 증명 지도 개선을 위한 하나의 방안이 될 수 있음을 밝히고자 하였다. Branford가 제시한 바와 같이 역사-발생적 전개를 통하여 증명의 의미를 지도하는 방안을 모색해 보고자, Euclid원론이 성립하기까지의 기하의 역사적 발달 과정과 병행하여 실험적, 직관적, 과학적 단계를 거쳐 발전되어 온 증명의 발생 과정을 살펴보고 지도 과정을 분석해 보았다. 그리고 실험적, 직관적 증명 단계를 거쳐 수학적인 증명을 도입하는 지도 과정에 따라 삼각형의 내각의 합에 대한 명제의 증명 지도를 중학교 1학년 학생들을 대상으로 실시해 보았다. 본 고에서는 그러한 결과를 통하여 역사-발생적 접근이 학생들에게 증명의 의미를 이해시키는데 큰 도움이 된다는 것을 확인하였다.

• 한국수학교육학회지시리즈C:초등수학교육
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• 제4권1호
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• pp.63-73
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• 2000

The purpose of this paper is to address He possibility of the teaching of 'proof' in elementary mathematics, on the assumption that proof in school mathematics should be used in the broader, psychological sense of justification rather than in the narrow sense of deductive, formal proof. 'Proof' has not been taught in elementary mathematics, traditionally. Most students have had little exposure to the ideas of proof before the geometry. However, 'Proof' cannot simply be taught in a single unit. Rather, proof must be a consistent part of students' mathematical experience in all grades. Or educators and mathematicians need to rethink the nature of mathematical proof and give appropriate consideration to the different types of proof related to the cognitive development of a notion of proof.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2012년도 추계 학술논문 발표대회
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• pp.63-64
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• 2012

Recently, Fire-proof performance of buildings becomes important to ensure safety. As a result, fire-proof paint is required for 3 hours. However, Experiments are only performed by standard KS F 2271 for estimation of fire-proof paint. Because there is no domestic estimation standard for performance of fire-proof paint as well. So estimation standard of fire-proof paint is needed to guarantee their performance for establishing quality system and to assure same performance for safety of people in the building from unpredicted fire accident. Owing to these reasons, we studied comparative estimation for quality performance of two kinds of fire-proof paint and bond performance.

• 한국수학교육학회지시리즈D:수학교육연구
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• 제7권1호
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• pp.1-10
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• 2003

This research reviewed literatures on proof in mathematics education. Several views of proof can be classified (and identified) such as psychological approach (Platonism, empiricism), structural approach (logicism, formalism, intuitionism) and social approach (ontology, axiomatic systems). All these views of proof are valuable in mathematics education society. The concept of proof can be found in the form of analytic knowledge not of constructive knowledge. Human beings developed their knowledge in the sequence of constructive knowledge to analytic knowledge. Therefore, in mathematics education, the curriculum of mathematics should involve the process of cognitive knowledge development.

• 한국지역사회생활과학회지
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• 제17권4호
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• pp.49-56
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• 2006

The purpose of this study was to evaluate the thermal and subjective comfort of various pesticide-proof clothes made from different material. Seven male adults took part in the study, conducted in a climate-chamber controlled with an ambient temperature of $30^{\circ}C$ and a relative humidity of 60%RH. The thermal and subjective responses of subjects wearing pesticide-proof clothing made of Goretex(coating treatment), polyester (water-repellent treatment), non-woven(coating) and nylon(coating) were measured. The main results were summarized as follows: (1) Change of rectal temperature and clothing microclimate were inhibited more effectively in pesticide-proof clothing made of Goretex, polyester and non-woven than nylon materials. (2) Mean skin temperature at the end of the experiment was significantly higher in subjects who wore nylon than non-woven and Goretex, and was lowest in those with pesticide-proof clothing made of polyester. (3) Change of heart rate was significantly lower in subjects with Goretex and polyester clothiing than those with non-woven, and in those with nylon, it was highest. (4) Subjective comfort was greater in subjects with Goretex, polyester and nonwoven clothing than nylon, except for thermal sensation. Thermal sensation was greater in order of polyester, Goretex, non-woven and nylon. Thus, it was concluded that pesticide-proof clothing made of Goretex, polyester and non-woven material could reduce thermal stress during the spraying of pesticides in summer.

• 한국의류학회지
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• 제11권2호
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• pp.91-100
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• 1987

To develop the comfortable pesticid-proof clothes, wearing trials for 7 types of existing pesticide-proof clothes were done measuring skin temperature, pulse rate, humidity and temperature of inside clothing and subjective feeling such as thermal, humid and comfort sensations at $28{\pm}1^{\circ}C$, $75{\pm}5\%$ RH, 2.3 m/sec wind speed. (Experiment 1). On the base of above results, wearing trials of 6 types of new pesticide-proof clothes and 3 types of pesticide-proof clothes as control group were done with the same method as experiment 1. (Experiment 2). The results obtained were as follows 1. Heat stress was lower in newly designed pesticide-proof clothes with mesh running shirts. 2. For the body temperature regulation, it was confirmed that 6 types of new pesticide-proof clothes made of microporous fabric were better than the others.

• 한국안전학회지
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• 제35권1호
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• pp.1-11
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• 2020

Article 325 (Prevention of Fire Explosion due to Electrostatic) of the Rule for Occupational Safety and Health Standard specifies that in order to prevent the risk of disasters caused by static electricity, fire, explosion and static electricity in the production process, However, in order to do this, it is absolutely necessary to use a pre-detection technology and a detector for antistatic discharge prediction, which is a precautionary measure by static electricity in a fire / explosion hazard place, but in Korea, And there is no technical standard for the application of the technology of the explosion proof structure of the related equipment. Research methods include domestic and overseas electrostatic discharge detection technology and literature investigation of related equipment explosion proofing technology, domestic and foreign electrostatic discharge detection device production and use situation investigation, advanced foreign technology data analysis and benchmarking. In particular, we sought to verify the results of empirical experiments using electrostatic discharge detection technology through sample purchase and analysis of related major products, development of optimization technology through prototype production, evaluation, and supplementation, and expert knowledge through expert consultation. The results of this study were developed and fabricated two prototypes of electrostatic discharge detector based on the technology / standard related to electrostatic discharge detection technology in Korea and abroad through development of electrostatic discharge detection technology and development and production of detector. In addition, based on the development of electrostatic discharge detection technology, we developed an intrinsic safety explosion proof ib class explosion proof technology applicable to the process of using and handling flammable gas and flammable liquid vapor and combustible dust. In the case of the over voltage and minimum voltage are supplied to the explosion-proof structure ESD detector, check the state of the circuit and the transient and transient currents generated by the coil and capacitor elements during the input and standby of the signal pulse voltage. Explosion-proof equipment-Part 11: Intrinsically safe explosion proof structure The comparative evaluation with the reference curve in Annex A of "i" confirms that the characteristics of the intrinsically safe explosion protection structure are met.

• 시스템엔지니어링학술지
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• 제15권2호
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• pp.39-46
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• 2019

The purpose of this paper is to present the results of the study, applying Systems Engineering(SE) method, on the feasibility of developing a Melt-down Proof Modular Micro Reactor(MDP-MMR) for its future deployment in Korea. The reactor is being developed by NCSU (North Carolina State University) due to its advantage of melt-down proof nature of the reactor core. For this paper, the characteristics of the MDP-MMR has been studied in terms of fuel characteristics, inherent safety features and passive safety system. The NCSU's development process has been reviewed applying the SE method, and further research is recommended for the feasibility study on deploying such a modular micro reactor in Korea.

• 대한수학교육학회지:수학교육학연구
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• 제13권1호
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• pp.13-28
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• 2003

Practice of proof is considered in, the view of language and meta-mathematics, recognizing the role of proof that is the means of communication and development of mathematical understanding. Linguistic components in proof texts are symbol, verbal language and visual text, and contain the implicit knowledge in the meta-mathematics view. This study investigates the functions of linguistic elements according to Halliday's functional grammar and the rhetoric skills in proof texts in math textbook, teacher's note, and student's written text. We need to inquire into the aspects of language for mathematics learning process and the understanding and use of students' language.