• Korean Journal of Logic
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• v.12 no.2
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• pp.31-58
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• 2009

This paper defends Stalnaker's theory of indicative conditionals. His theory consists of selection functions and pragmatic constraints. The selection function takes a certain possible world(W) and a proposition(A) to yield a possilble world that is similar to W and in which A is true. And the pragmatic constraints plays role to make selection functions apply just to indicative conditionals. According to Stalnaker, as indicative conditionals has strong truth-value, uncontested principle always holds but passage principle does not always hold. However, his theory can explain why passage principle sometimes holds by means of pragmatic constraints. Also, this paper argues that Stalnaker's theory is the most acceptable one among others, by replying to criticisms suggested by Adamsians and the problem raised by Gibbard and other criticisms.

• Journal of Educational Research in Mathematics
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• v.17 no.3
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• pp.253-270
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• 2007

by A.C. Clairaut was written based on the historico-genetic principle such as his . In this paper, by analyzing his we can induce six principles that Clairaut adopted to teach algebra: necessity and curiosity as a motive of studying algebra, harmony of discovery and proof, complementarity of generalization and specialization, connection of knowledge to be learned with already known facts, semantic approaches to procedural knowledge of mathematics, reversible approach. These can be considered as strategies for teaching algebra accorded with beginner's mind. Some of them correspond with characteristics of , but the others are unique in the domain of algebra. And by comparing Clairaut's approaches with school algebra, we discuss about some mathematical subjects: setting equations in relation to problem situations, operations and signs of letters, rule of signs in multiplication, solving quadratic equations, and general relationship between roots and coefficients of equations.

• The Journal of the Korea Contents Association
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• v.6 no.2
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• pp.51-58
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• 2006

The enhancement of antenna near-field measurements is obtained using a general probe compensation equation based on the Lorentz reciprocity theorem and reciprocity notation. The probe compensation is an essential process of the near-field to far-field transformations. Applying the equation proposed in this paper to a planar scanning for a rectangular horn antenna shows that our near-field radiation pattern is similar to that of a far-field and our theory is very simple to use and suitable for most practical applications.

• Resources Recycling
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• v.7 no.5
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• pp.41-45
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• 1998

A Hew way of contact angle measurement is derived based on simple geometrical calculation. Without using complicated contact angle measurement instrument. Just measuring the diameter and height of liquid lens made it possible to calculate the contact angle value with a reasonable reliability. To validate the contact angle value obtained by this method, contact angle of the same liquid lens is measured using conventional goniometer and it is verified that two values are nearly same within the limit of observational error.

• Progress in Medical Physics
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• v.6 no.1
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• pp.19-37
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• 1995

The use of lasers in medicine has opened up entirely new fields of therapy and diagnosis. The process in biotechnical applications of laser is basically different from traditional one in other technical field because of critical account to the human body. This paper surveys the principle of biomedical applications as well as possible future developments in laser medicine. In particular, the following subjects are extensively presented : 1) laser-tissue interaction, 2) therapeutic, and diagnostic technique, 3) laser op tical fiber for medicine, and 4) laser safety.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2013.05a
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• pp.37-37
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• 2013

무전해도금법 (electroless plating)은 Brenner와 Riddell이 1946년에 처음으로 환원제를 이용한 금속의 침적을 electroless plating이라고 명명한 뒤 전기를 이용하지 않고 금속막을 얻을 수 있는 방법으로 인지되어왔다. 초기에는 용액이 불안정하였으나 용액의 안정성을 향상시키면서 꾸준히 산업체에 쓰여왔다. 무전해도금의 응용이 처음에는 니켈에 국한되었으나 구리의 무전해도금이 PCB에 사용되면서 80년대부터 전자산업에서 많이 쓰이게 되었다. 최근에는 무전해도금을 이용한 전자산업뿐만 아니라 MEMS와 같이 전기도금을 위한 전기접촉이 어려우면서 정밀한 균일도를 요구하는 분야에도 많이 쓰이고 있다. 본 발표에서는 무전해도금법의 일반적인 원리와 이를 이용한 IT 산업에서의 응용에 대하여 알아본다.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.10 no.16
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• pp.113-119
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• 1987

A Multistage production-inventory model is developed for deteriorating items. The model is developed deterministic but time-varing demand pattern and instantaneous delivery. Deterioration rates are assumed to vary from period to period. Discrete version of Pontryagin's maximum principle is used to present the efficient alogrithm to solve this model easily. A numerical example is given to illustrate the derived results.

• Journal of the korean Society of Automotive Engineers
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• v.18 no.6
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• pp.40-45
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• 1996

전자제어를 이용한 자동차의 제어란 인간의 감각 기관과 같은 센싱부, 두뇌와 같은 전자제어 유니트부, 명령을 수행하는 액츄에이터로 구성되어 있다. 그 중 센서는 각가지 물리량 및 화학량을 전자제어 유니트가 이해할 수 있는 전기적인 양으로 변환하여 전달하는 부품이라고 할 수 있으며 매우 다양한 원리와 구조로 이루어져 있다. 그 중에서 자동차에서 일어나는 가장 일반적인 물리량인 가속도, 압력, 충격, 변위, 온도 등을 센싱할 수 있는 재료인 세라믹 재료는 자동차의 전자화에 따라서 그 적용범위가 크게 확대되어 왔다고 할 수 있다. 세라믹이란 단결정의 무질서 집합체이며, 가장 일반적인 것은 원료 분말을 조합해서 그 성형체를 고열로 소성함으로서 만들어진다. 세라믹은 절연성, 유연성, 압전성, 초전성, 반도체적 특성 등 센서와 관련된 많은 유용한 전자적 기능들을 보유하고 있어 세라믹이 아니고는 실현할 수 없는 기능들도 많이 생겨나게 되었다. 본 기고에서는 세라믹의 자동차 센서에의 응용에서 가장 일반적으로 사용되고 있는 압전 효과를 이용한 센서 재료와 서미스터를 이용한 온도센서 재료에 대해서 소개하고자 한다.

• Solar Energy
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• v.18 no.2
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• pp.51-67
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• 1998

In this paper, various solar systems are introduced according to usage pattern considering national weather condition and hot water comsumption pattern. First, basic principle and components of solar hot heater are presented, and then operational machanism of various solar hot water systems are presented according to the case of domestic and industrial use with network of piping.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2006.05a
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• pp.709-712
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• 2006

일반적인 침입탐지 시스템의 원리를 보면 공격자가 공격 패킷을 보내면 침입탐지서버에 IDS 프로그램으로 공격자의 패킷을 기존의 공격패턴과 비교하여 탐지한다. 공격자가 일반적인 공격 패킷이 아닌 패킷을 가짜 패킷과 공격 패킷을 겸용한 진보된 방법을 사용할 경우 IDS는 이를 탐지하지 못하고 로그 파일에 기록하지 않는다. 이는 패턴 검사에 있어 공격자가 IDS를 속였기 때문이다. 따라서 공격자는 추적 당하지 않고서 안전하게 공격을 진행할 수 있다. 본 논문에서는 이러한 탐지를 응용프로그램 단계가 아닌 커널 단계에서 탐지함으로서 침입탐지뿐만 아니라 침입 방지까지 할 수 있도록 하였다.