• 한국수학교육학회지시리즈D:수학교육연구
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• 제13권3호
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• pp.217-233
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• 2009

The purpose of this study is to describe how dynamic geometry systems can be useful in proof activity; teaching sequences based on the use of dynamic geometry systems and to analyze the possible roles of dynamic geometry systems in both teaching and learning of proof. And also dynamic geometry environments can generate powerful interplay between empirical explorations and formal proofs. The point of this study was to show that how using dynamic geometry software can provide an opportunity to link between empirical and deductive reasoning, and how such software can be utilized to gain insight into a deductive argument.

• 한국의류학회지
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• 제14권4호
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• pp.281-291
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• 1990

Experiment I and II had done to develop the solar heat proof hat for field work in the summer. In the experiment I physical characteristics of several fabrics was tested to determine which one Is proper to make the solar heat proof hat. On the base of above results in the experiment II three improved solar heat proof hat was deviced and tested solar heat proof effect and compared the existing summer working hat by wearing trials in the environmental chamber. The results obtained were as follows. 1. In the view of the physical characteristics of six fabrics (Blue T/C, White poplin, Vapor transfer silver coating nylon taffeta, No vapor trans(or silver coating nylon taffeta, Aluminum coating T/C, Microporous fabric), the light color T/C and no vapor transfer silver coating nylon ta(feta is proper to make improved solar heat proof working hat. 2. Three improved hats that are made of white T/C, grey T/C and no vapor transfer silver coating nylon taffeta have more solar heat proof effect than the existing summer working hat. 3. Among the three improved hats, the improved hat that is made of no vapor transfer silver coating nylon taffeta is most effective to proof the solar heat.

• 한국수학교육학회지시리즈C:초등수학교육
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• 제7권2호
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• pp.85-99
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• 2003

In this paper, firstly examined various proofs types that cover informal empirical justifications by Balacheff, Miyazaki, and Harel ＆ Sowder and Tall. Using these theoretical frameworks, justification activities by 5th graders were analyzed and several conclusions were drawn as follow: 1) Children in 5th grade could justify using various proofs types and method ranged from external proofs schemes by Harel & Sowder to thought experiment by Balacheff This implies that children in elementary school can justify various mathematical statements of ideas for themselves. To improve children's proving abilities, rich experience for justifying should be provided. 2) Activities that make conjectures from cases then justify should be given to students in order to develop a sense of necessity of formal proof. 3) Children have to understand the meaning and usage of mathematical symbol to advance to formal deductive proofs. 4) New theoretical framework is needed to be established to provide a framework for research on elementary school children's justification activities. Research on proof mainly focused on the type of proof in terms of reasoning and activities involved. But proof types are also influenced by the tasks given. In elementary school, tasks that require physical activities or examples are provided. To develop students'various proof types, tasks that require various justification methods should be provided. 5) Children's justification type were influenced not only by development level but also by the concept they had. 6) Justification activities provide useful situation that assess students'mathematical understanding. 7) Teachers understanding toward role of proof(verification, explanation, communication, discovery, systematization) should be the starting point of proof activities.

• 대한안전경영과학회지
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• 제21권3호
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• pp.17-21
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• 2019

With the development of public transportation, the use of subways as a means of transportation in the city center is increasing, so that vibrations and structural noises are emerging as a new environmental issues. This study can be used as a basis for research on subway safety and shock mitigation by applying vibration-proof mat.

• 한국의류학회지
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• 제31권11호
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• pp.1611-1620
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• 2007

The precaution to spray with agricultural chemicals is very important, in particular personal protective equipment against pesticide in order to protect farmers# pesticide poisoning. The Ministry of Agriculture and Forestry has proclaimed the announcement of pesticide proof clothing(PPC) in 1983, and revised it in 1987. The announcement had many performance items to achieve the high-quality protective clothing for pesticide including weight, density, force strength, dimensional change(in washing and drying), fastness(dyeing, washing, sweating and rubbing) and water resistance of clothes. Announcement of the PPC has better durability and penetration resistance function than former days, but the plenty of farmers didn#t wear it because of the intolerable heat. To increase wearing rates, the pesticide proof clothing must be estimated the water-vapour resistance. From the results, the developed PPC with polyester treated water-repellent showed the more excellent comfort than an existing PPC with nylon coated polyurethane. But the developed PPC appeared to have the low water-vapour resistance. Therefore, it is suggested that the property of pesticide penetration must be evaluated through the field test in the future study.

• 의료법학
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• 제9권1호
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• pp.9-56
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• 2008

The medical practice does not always get a satisfatory result since the disease progress of patients are depended on patients' physical constitution and the doctors cannot control the outcomes about patients' physiological and biological reaction after the treatment. Moreover, the medical practice may bring wrong result fatalistically because of the unpredictablility of life. To demand for compensation of the damage to the doctors about these wrong result, the patient side holds the burden of proof that is between medical practice and demage, and there is damage from doctor's malpractice according to the accepted theory about the fundamental principle of distribution of the burden of proof. This falls not only under the liability of Tort Law, but also liability of Contract Law. However, the patient may be in difficult situation to prove the malpractice of doctors since he or she cannot recognize the facts because he or she was in unconscious while the medical practice was conducted, or they cannot judge precisely even though they recognize the facts. Nevertheless, the lawsuits against medical malpractice are the field that never achieves the equality of arms since the most of the evidence belong to the doctor's side. Hence, to maintain the principle of the equality of arms under the constitution, the theory leads to alleviate the burden of proof that patients hold. However, the doctors cannot be asked for the burden of proof that they conduct medical practice without errors. Because the doctors may experience difficulty to prove their innocence as the patients because of the unique characteristic that medical practices have. Therefore, the methods of the alleviation of the patient's burden of proof should have the equality of arms and the equal opportunity between the patients and the doctors with the evaluation of the justifiable interest from both the patients and the doctors. As the methods of the alleviation of the burden of proof, the alleviation of the demands and the degree of the burden of proof or resolutely the conversion of the burden may be considered. However, Recognizing the exception from general principle with converting the burden of proof is not proper in principle because the doctors may experience difficulty of the proof as the patients may have. If the difficulty of proof can be resolved by alleviating of the demands and the degree of the burden of proof, it is more desirable resolution rather than converting the burden of proof.

• 대한수학교육학회지:학교수학
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• 제18권4호
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• pp.839-856
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• 2016

2009 개정과 2015 개정 수학과 교육과정에서는 학생들의 인지발달 수준을 고려해 '증명'을 중학교에서 고등학교로 옮기는 한편, 7차와 2007 개정 교육과정에서 공식적으로는 도입되지 않았던 '귀류법'을 고등학교 1학년 과목의 '학습내용 성취 기준'에 명시하였다. 귀류법은 어떤 명제가 참임을 보이기 위해 오히려 그 명제를 부정하는 귀류법 가정의 독특함으로 인해 인지적 갈등을 유발하는 것으로 알려져 있다. 이 논문에서는 귀류법에 대한 논리수학적 및 역사적 분석을 바탕으로 새로이 도입된 현 교과서의 귀류법 도입 및 활용에 대해 살펴보고 발견, 설명, 융합 등의 관점에서 개선 방안을 모색하였다. 발견의 과정을 먼저 서술한 후 귀류법적 사고를 도입하고, 귀류법 가정이 직접적으로 필요하지 않은 부분을 분리시켜 설명하되 유기적으로 서술하며, 대우를 이용한 증명법과의 관계를 밝혀 상호 보완적으로 다루고, 융합교육적 관점을 도입할 것 등을 제안하였다.

• 한국정밀공학회지
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• 제19권7호
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• pp.7-19
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• 2002

• 한국정밀공학회지
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• 제21권9호
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• pp.135-141
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• 2004

Anti-shock performance is one of the most important design specifications of TFT-LCD modules. Since they are adopted fur major display units of many mobile applications such as lap-top PCs, cellular phones, and palm pilots, they are able to accommodate and endure high level transient mechanical energy inputs. For the reasons, not only the LCD unit manufacturers but their customers like PC makers perform a series of strict impact/drop test on the units. Currently, designers are mostly relying on their own trial-error based experience for the anti-shock design. Thus those designs depending on only experience may result in disqualification from the drop/impact test during final product evaluation. Those shock failures of any new designs are prohibitive for both LCD and PC manufacturers. In order to avoid this problem, many designers are focusing on the development of computer-aided design tools that is directly connected to shock simulation capabilities and then shock-proof design cycle time could be significantly reduced. Development of an integrated CAE system for the shock-proof design is presented in this article. At every stages of the development of present work, practical industrial applicability and mass production feasibility are seriously considered and tested so that the system is to be used in the LCD design engineering field.

• 한국산업안전학회:학술대회논문집
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• 한국안전학회 1997년도 추계 학술논문발표회 논문집
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• pp.135-142
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• 1997

For lighting of dark and hazardous workplaces such as compartments of ships under construction, workers should use hand lamps of explosion-proof type. However, the heavy weight of such lamps has prevented most impatient workers from using such types of lamps extensively. In this paper, ire developed a light weight hand lamp of intrinsic safety type which reduced the weight a lot while maintaining or improving the lighting and explosion-proof function. We made a Prototype which consisted of lamp fixture and low/high frequency power supply. Testing results show that the hand lamp meets well all the explosion-proof testing requirements of the Korea Industrial Safety Corporation.