• Proceedings of the Korean Society for Cognitive Science Conference
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• 2000.05a
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• pp.252-257
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• 2000

개념지식인 범주지식과 각본지식의 표상 차이를 검증하기 위해서 두 개의 실험을 실시하였다. 실험 1 에서는 상위 개념을 점화단어로 제시하고 하위 개념을 목표단어로한 명명과제를 실시하였다. 전형조건이 비형성조건에 비해서 명명시간이 빨랐다. 범주지식에서는 전형성의 효과가 관찰되었지만 각본지식에서는 전형성 효과가 관찰되지 않았다. 실험 2에서는 하위 개념을 점화단어로 제시하고 상위 개념을 목표단어로한 명명과제를 실시하였다. 범주지식이 각본지식에 비해서 명명시간이 빨랐으며, 범주지식에서는 전형성의 효과가 관찰되었지만 각본지식에서는 그 효과가 관찰되지 않았다. 이는 개념지식의 유형에 따라서 상위-하위 개념의 표상체계가 다르게 구성됨을 시사한다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2002.04a
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• pp.62-63
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• 2002

램젯 엔진을 장착한 미사일은 기존의 터보젯 이나 터보팬 엔진에 비해 압축기와 터빈과 같은 엔진 구성품이 없어 무게가 가볍고 초음속에서 저항도 적으며 고속의 비행영역에서 연료효율과 생존성능이 뛰어나기 때문에 차세대 미사일 추진 시스템으로서 세계 여러 국가에서 개발 및 운용이 이루어지고 있다. 하지만 램젯 엔진은 충분한 램 효과를 얻어야 초기 점화가 가능하기 때문에 현재 개발되고 있는 대부분의 시스템은 최초 발사시 로켓 부스터에 의해 가속하고 로켓연료를 모두 소모하고난 후에 흡입구가 개방되어 램젯 엔진이 점화하는 방식을 취하고 있다.

• Korean Journal of Cognitive Science
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• v.15 no.1
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• pp.35-41
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• 2004

The letter delay task using monosyllabic words has been employed in order to investigate whether Korean word is processed by the phonological route, and to investigate which stage this phonological information affects word recognition. Two main conditions were delaying a sounding letter( $\rightarrow$향), and delaying a silent letter( $\rightarrow$양). Experiment 1 was the naming task with the SOAs of 150㎳ and 250㎳ in order to investigate whether the phonological information affects the early stages, or the later stages of word recognition. The results showed that the interaction between the phonological value condition and the presence/absence of the prime was significant under the 150㎳ SOA, but not under 250㎳ SOA. Experiment 2 was conducted in order to generalize the results of Experiment 1 in the lexical decision task. The results showed the similar pattern as the Experiment 1. These experiments indicate that Korean words are processed by the phonological route, and the phonological information plays roles in the early stages of word recognition.

• Journal of Energy Engineering
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• v.18 no.3
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• pp.163-168
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• 2009

This paper describes the homogeneous charge compression ignition (HCCI) engine for a new concept. HCCI engines are being considered as a future alternative for diesel and gasoline engines. HCCI engines have the potential for high indicated thermal efficiency under part load and very low NOx emissions. The objective of this paper is to clear the effects of exhaust gas recirculation (EGR) rate on the HCCI. For this purpose, a 4-cylinder, compression ignition engine was converted into a HCCI engine This work has been run with propane and butane fuels at a constant speed.

• Journal of the Korean Society of Propulsion Engineers
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• v.12 no.3
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• pp.1-8
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• 2008

We present a model for simulating high energy laser heating of metal for ignition of energetic materials. The model considers effect of ablation of steel plate with long laser pulses and continuous lasers of several kilowatts and the thermal response of well-characterized high explosives for ignition. Since there is enough time for the thermal wave to propagate into the target and to create a region of hot spot in the high explosives, electron thermal diffusion of ultra-short (femto- and pico-second) lasing is ignored; instead, heat diffusion of absorbed laser energy in the solid target is modeled with thermal decomposition kinetic models of high explosives. Numerically simulated pulsed-laser heating of solid target and thermal explosion of RDX, TATB, and HMX are compared to experimental results. The experimental and numerical results are in good agreement.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.451-455
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• 2017

The reactive Eulerian-Lagrangian code is utilized to simulate combustion of ZPP/THPP in a closed vessel. In the paper, ignition delay of THPP is mainly studied since ZPP and THPP are isolated by a boron nitride wall. Only a numerical case study is conducted as experimental observation is inaccessible. Results showed THPP ignition delay affects initial shock strength thus not only the first peak become weak, but also the frequency of a pressure oscillation is slowed.

• Proceedings of the Korean Society for Cognitive Science Conference
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• 2002.05a
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• pp.125-130
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• 2002

우리의 언어생활을 비추어 볼 때 한자어 정보처리는 많은 연구가 이루어야 함에도 불구하고 고유어 언구에 비해 소흘해 다루어져 왔다. 본 연구는 단일 한자어를 구성하는 각 음절이 단어의 재인에 어떤 영향을 미치는지 점화과제를 통하여 알아보았다. 본 실험은 기존의 한자어 연구에 빈도특성과 고유어와 외래어의 글자특성까지 고려하여 종합적으로 살펴보았다. 먼저 실험1의 어휘판단관제에서는 고유어와 한자어의 양상이 비슷하며 외래어는 다른 처리를 하는 것으로 드러났다. 고유어와 한자어는 빈도에 따라 영향을 받지만 외래어는 빈도의 영향에 변함없이 일정하게 나타났다. 이런 결과는 한국인은 고유어와 한자어를 동일한 양상으로 처리하며 이런 이유는 외래어의 한국어와는 다른 음운규칙이나 음절규칙의 영향으로 해석할 수 있겠다. 실험 2에서는 한자어 형태소와 의미적으로 유사한 조건(강도-강력)과 철자적 유사 조건(강도-강변), 고유어 유사 조건(강도-강정)조건을 점화과제를 이용하여 어휘판단을 하게 하였다. 실험 결과 모든 조건이 통제조건에 비하여 빠르게 나왔다. 그리고 의미적 유사 조건이 촉진적 점화효과를 일으키고, 철자적 유사조건은 억제 효과를 일으켰으며 고유어는 특이하게도 판단시간이 빠르게 나와 한자어와는 다른 처리과정이 있음을 보여주고 있다. 이런 결과는 지연조건에서도 동일하게 일어나고 있다. 이런 결과는 한자어는 어휘접근 이후에도 실험의 과제 특성상 한자어 형태소는 단어 수준 아래 위치하기는 힘든 반면, 고유어는 단어 수준 아래에 존재한다고 할 수 있다. 결국 한자어와 고유어는 기본적으로 외래어와 다른 처리를 보이면 한자어와 고유어 내에서도 한자어는 단어접근 전에 의미접근의 단계를 거쳐야 하지만 고유어는 각 음절이 형태소가 아니기 때문에 바로 어휘에 접근하는 것이라고 할 수 있겠다.ulic geometry and sediment transport has been applied to: (1) gravel-bed transport measurements in a cobble-bed stream at Little Granite Creek, Wyoming; (2) sand and gravel transport by size fraction in the sharp meander bends of Fall River, Colorado; (3) changes in sand dune geometry and resistance to flow during major floods of the Rhine River in the Netherlands; (4) changes in hydraulic geometry of the Rio Grande downstream of Cochiti Dam, New Mexico; and (5) analysis of the influence of water temperature and the Coriolis force on flow velocity and sediment transport of the Lower Mississippi River in Louisiana. Recent developments also include two textbooks on "Erosion and Sedimentation" and "River Mechanics" by the author and state-of-the-art papers in the ASCE Journal of Hydraulic Engineering.rk on is diversified, the importance of skills are diversified in each field of jobs.

• Korean Journal of Cognitive Science
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• v.4 no.1
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• pp.51-86
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• 1993

The purpose of this study was to investigate on-line comprehension processing in pronoun resolution. The two important constraints investigated in this study were the gender cue of pronoun and the antecedent case. Using antecedent probe recognition task. Experiment 1 investigated the effects of gender cues and antecedent cases on probe recognition time. There were on signigicant effects of employed variable. This result suggest the possibilty of immediate antecedent assignment depending on the degree of syntactic constraints satisfaction. In Experiment 2. using antecedent probe recognition task. the primed activation level differences between antecedents and non-antecedents over time-course intervals from 0 to 250msec were measured. The effect of gender cues was obtained over 0-250msec time-course condition. This indicates that the gender cues can determine the assignment of proper antecedent for a pronoun. In Experiment 3, subect-case pronouns were used only:Unambiguous gender cues were given and the time-course intervals of 250 and 750msec were employed. A signigicant interaction effect of antecedent cases with probe conditions was obtained. All the results of this research suggest that gender cues are powerful constraints for pronoun resolution.

• Korean Journal of Cognitive Science
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• v.23 no.3
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• pp.323-348
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• 2012

Three experiments were conducted to explore the interaction of personal pronoun (e.g. 'I' and 'you') and emotional evaluation (e.g. positive and negative) using time-course (e.g. SOA 500-1000ms) and multi-task approaches (e.g. lexical decision task and primed naming task). In Experiment 1, Participants were presented personal pronoun as primes at SOA 1000ms and were asked to response emotional words which were differed in emotional attributes. The results showed that the interaction effects of personal pronoun and emotional words were found. In Experiment 2, Participants were presented personal pronoun as primes at SOA 1000ms and were asked to response emotional words which were differed in emotional attributes. The results showed that no effects were found. In Experiment 3, Participants were presented personal pronoun as primes at SOA 500ms and were asked to pronounce emotional words which were differed in emotional attributes. The results showed that the interaction of personal pronoun and emotional words were found. The results of 3 experiments were discussed from a point of view of dynamic processes of social cognition.

• Korean Journal of Cognitive Science
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• v.26 no.1
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• pp.1-26
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• 2015

The purpose of this study was to examine whether the phonological information or the orthographic information plays a major role in visual word recognition. To do so, we used a non-word lexical decision task(LDT) in Experiment 1 and masked priming tasks in Experiement 2 and 3. The results of Experiment 1 showed that reaction times and the error rates were affected by the orthographic characteristics of the non-word stimuli such that orthographically similar non-words condition showed prolonged reaction times and higher error rates than control condition. In Experiment 2 and Experiment 3, the participants performed masked priming lexical decision tasks in two SOA conditions(60ms, 150ms). The results of the both experiments showed that the orthographically identical first syllable priming facilitated lexical decision of the target words while both of the pseudo-homophone priming and the phonologically identical first syllable priming did not. The dual route hypothesis(Coltheart et al, 2001), assuming that orthographic information rather than phonological information is the major source for the visual word recognition processes, fits well with the results of the current study.