• 정보보호학회논문지
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• 제21권5호
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• pp.83-94
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• 2011

RFID 요킹증명은 2004년 A. Juels에 의해 제안된 개념으로써, 한 쌍의 태그가 하나의 리더에 의해 동시에 스캔됐음을 증명하는 것이다. A. Juels가 최초로 제안한 요킹증명 프로토콜은 이 후 재생공격에 취약한 문제점이 지적되었고, 이를 개선하기 위해 여러 다른 요킹증명 프로토콜들이 제안되었다. 그러나 최초 제안된 기법이 태그의 낮은 성능을 고려해 프로토콜의 경량화를 중요한 이슈로 보았던데 비해, 현재까지 알려진 요킹증명 프로토콜들은 상대적으로 태그에 더 많은 연산량과 저장공간을 필요로 하는 단점이 있다. 우리는 요킹증명의 기본적인 조건을 모두 만족시키면서 성능이 낮은 수동형 태그를 고려한 안전한 프로토콜 두 가지를 제안한다. 제안하는 기법은 기존에 알려진 재생공격뿐만 아니라 전수공격에 있어서도 높은 안전성을 보장하며, 한 쌍 이상의 태그 그룹, 흑은 다수의 태그 그룹들을 한번의 프로토콜 수행으로 증명할 수 있도록 설계되었다.

• 한국학교수학회논문집
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• 제11권1호
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• pp.55-68
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• 2008

이 연구에서는 중학생들이 '원의 성질' 단원의 증명학습 과정에서 어떤 어려움을 겪는지를 조사하여 GSP를 활용한 증명학습이 학생들의 어려움을 어떻게 완화시키는지를 탐구하였다. 진단검사를 통해, 학생들은 가정과 결론의 이해, 기호의 사용, 추론 과정 등에서 어려움을 겪고 있음을 확인하였다. 한편, 학생들은 GSP를 활용한 증명학습을 통해 자신의 추측이나 추론에 대한 피드백을 받을 수 있고, 구체적인 사례를 일반화하거나 증명에 필요한 아이디어를 능동적으로 찾는 탐구 태도를 형성할 수 있다는 것을 확인하였다.

• 한국강구조학회 논문집
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• 제14권2호
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• pp.329-337
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• 2002

본 연구는 국내에서 차량의 안전주행을 유도하기 위하여 곡선교, 고가차도 등의 포장면에 설치하는 미끄럼방지포장이 강상자형 교량에 미치는 영향을 분석하기 위하여 강상자형 교량에서 현장재하시험과 전산구조해석을 실시, 상호 비교함으로서 강상자형 교량의 동적 응답을 분석하였다. 강상자형 교량의 현장재하시험에서는 미끄럼방지포장전후의 고유진동수와 동적처짐을 측정하였으며 전산구조해석에서는 현장재하시험 교량의 제원을 입력값으로 하여 미끄럼방지포장전후의 동적응답을 해석하여 현장재하시험과 상호 비교 분석하였다. 본 연구는 분석한 자료를 바탕으로 미끄럼방지포장과 같은 도로시설물이 교량의 동적응답에 미치는 영향에 대해 기초자료를 제시하는데 그 목적이 있다.

• 한국의류산업학회지
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• 제8권6호
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• pp.727-732
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• 2006

The purpose of this study was to investigate the effects of flame-proof clothing on physiological responses and subjective sensation. We measured rectal temperatures, local skin temperature, clothing microclimate, blood pressure, heart rate, body weight loss and subjective sensation during 90 minutes (30 min of rest, 45 min of exercise and 15 min of recovery periods). Seven male subjects wore flame-proof clothing or reformed flame-proof clothing under the environmental condition of $35{\pm}1^{\circ}C$, $45{\pm}5%$ RH and $25{\pm}1^{\circ}C$, $50{\pm}5%$ RH. The results of this study were as follows; Rectal temperature, mean skin temperature, clothing microclimate and blood pressure were significantly lower levels in reformed flame-proof clothing. Heart rate and body weight loss were also showed lower levels. Subjects replied less hot, less uncomfortable and less wet in wearing a reformed flame-proof clothing. Our present results suggest that the ventilation through of gusset in underarm seam and zipper in sideseam of slacks are qualitatively useful for physiological needs.

• 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.

• 대한수학교육학회지:수학교육학연구
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• 제9권1호
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• pp.245-261
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• 1999

Proof is an essential characteristic of mathematics and as such should be a key component in mathematics education. But, teaching proof in school mathematics have been unsuccessful for many students. The traditional approach to proofs stresses formal logic and rigorous proof. Thus, most students have difficulties of the concept of proof and students' experiences with proof do not seem meaningful to them. However, different views of proof were asserted in the reassessment of the foundations of mathematics and the nature of mathematical truth. These different views of justification need to be reflected in demonstrative geometry classes. The purpose of this study is to characterize the types of students' justification in demonstrative geometry classes taught using dynamic software. The types of justification can be organized into three categories : empirical justification, deductive justification, and authoritarian justification. Empirical justification are based on evidence from examples, whereas deductive justification are based logical reasoning. If we assume that a strong understanding of demonstrative geometry is shown when empirical justification and deductive justification coexist and benefit from each other, then students' justification should not only some empirical basis but also use chains of deductive reasoning. Thus, interaction between empirical and deductive justification is important. Dynamic geometry software can be used to design the approach to justification that can be successful in moving students toward meaningful justification of ideas. Interactive geometry software can connect visual and empirical justification to higher levels of geometric justification with logical arguments in formal proof.

• 한국재료학회지
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• 제19권7호
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• pp.382-385
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• 2009

Efforts to reduce noise in industrial application fields, such as automobiles, aircrafts, and plants have been gaining considerable attention while a sound proof wall to protect people from the noise has been intensively investigated by many researchers. In this study, our research group suggested creating a new sound proof wall composed of scrap aluminum chips and perforated plates in a commercial polyester sound proof wall, which was then successfully fabricated. This wall's sound absorption characteristics were measured by an impedance tube method. The sound absorption property was evaluated by measuring the Noise Reduction Coefficient (NRC) to the standard, ASTM C 423-90a. The noise reduction coefficient of the sound proof wall composed of 3.5 vol.% and 7.5 vol.% of scrap aluminum chips relatively increased to 5% and 8% compared to the commercial polyester sound proof wall. The scrap aluminum perforated plate also relatively increased to 13% compared to the commercial polyester sound proof wall.

• 무역학회지
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• 제44권6호
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• pp.135-150
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• 2019

Under the Manufacturing Liability Act, consumers want to be protected from manufacturers by mitigating burden of proof as an important target to be protected. However, due to the complexity of the product, it is very difficult for consumers to prove defects from the manufacturing defect. This situation has led to a major revision of the Manufacturing Liability Act, which mitigates the burden of proof of consumers by applying fruitless liability. The Manufacturing Liability Act is comparable to the U.S., which has strong consumer rights and is protected by the Manufacturing Liability Act. The burden of proof can be regarded as the most necessary content for consumers within the manufacturing product liability law when responding to manufacturing defects. The U.S. intends to provide implications for achieving consumer protection in Korea's Manufacturing Liability Act by imitating the U.S. based on the burden of proof. Case comparison regarding burden of proof can be conducted based on various criteria, including criteria for each product and key features for determining the importance of the manufacturing product liability law. The Act on the Responsibility of Korean Manufacturing Products for the Protection of Consumers was developed based on the assessment criteria, and a remedy was proposed to protect consumers who suffered from manufacturing defects.

• 한국수소및신에너지학회논문집
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• 제33권4호
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• pp.383-390
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• 2022

Appropriate explosion proof electrical equipment should be installed in hazardous areas. In areas where hydrogen is handled, explosion proof electrical equipment adjacent to the hydrogen handing facility must be reviewed for selection of gas group IIC (or IIB+H₂) equipment. When selecting explosion proof electrical equipment for the flammable substance handling facility in areas where hydrogen and flammable substance are handled, the method to avoid gas group IIC (or IIB+H₂) equipment has been suggested by using the operating pressure of the hydrogen handling facility. When the operating pressure of the outdoor hydrogen handling facility is 1.065 MPa or less, it has been confirmed that there is no need to install gas group IIC (or IIB+H₂) equipment for the flammable substance handling facility adjacent to the hydrogen handling facility. And the method of selecting explosion proof electrical equipment for the flammable substance handling facility has been suggested as a flowchart, so it will be able to be utilized when selecting appropriate explosion proof electrical equipment.

• East Asian mathematical journal
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• 제25권3호
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• pp.299-320
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• 2009

In mathematics, the education of the geometry proof has been playing an important role in promoting the ability for logical thinking by means of developing the deductive reasoning. However, despite of those importance mentioned above, considering the present condition for the education of the geometry proof in middle schools, it is still found that most of classes are led mainly by teachers, operating the cramming system of eduction, and students in those classes have many difficulties in learning the geometry proof course. Accordingly this thesis suggests the other method that is distinguished from previous proof educations. The thesis of Kai-Lin Yang and Fou-Lai Lin on 'A Model of Reading Comprehension of Geometry Proof (RCGP)', which was published in 2007, have various practical examples based on the model. After composing classes based on those examples and instructing the geometry proof, found out a problem. And then advance a new teaching model that amendment and supplementation However, it is considered to have limitation because subjects were minority and classes were operated by man-to-man method. Hopefully, the method of proof education will be more developed through performing more active researches on this in the nearest future.