• Korean Journal of Ecology and Environment
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• v.56 no.4
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• pp.406-413
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• 2023

Captive breeding and reintroduction are crucial strategies for conserving endangered species populations. However, fish raised in predator-free environments, show a lack of recognition of predationrelated stimuli such as chemical and visual signals. It is critical to recognize chemical signals from injured conspecifics, also known as alarm signals, and the order or shape of predators to indicate the spread of predation risk in the habitat. We conducted a laboratory experiment to determine and adjust the optimal exposure period to induce appropriate anti-predator behavior response to different types of stimuli (Chemical, Visual and Chemical+Visual) for the endangered species Microphysogobio rapidus. Our results demonstrate that predator avoidance behavior varies depending on the types of stimuli and the duration of predation risk exposure. First, the results showed captive-breed M. rapidus show lack of response against conspecific alarm signal (Chemical cue) before the predation risk exposure period and tend to increase response over predation risk exposure time. Second, response to predator (visual cue) tend to peak at 48 hours cumulative exposure, but show dramatic decrease after 72 hours cumulative exposure. Finally, response to the mixed cue (Chemical+visual) tend to peak prior to the predation risk exposure period and show reduced response during subsequent exposure periods. This experiment confirms the lack of responsiveness to conspecific alarm signals in captive-bred M. rapidus and the need for an optimal nature behavior enhancement program prior to release of endangered species. Furthermore, responsiveness to predator visual signal peak at 48 hours cumulative exposure, suggest an optimal predation risk exposure period of up to 48 hours.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.1D
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• pp.65-72
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• 2011

When an expressway intersects another expressway, a unique connector needs to be designed between the two consecutive exit ramps. In such a case, it is important to design a connector such that there is enough distance for drivers to find their way safely. A current design manual in Korea prescribes the minimum length of the connector as 240 m. In this research, we have suggested a method for calculating the minimum length of a connector in order to check the feasibility of the currently prescribed length. For this purpose, we have attempted to determine the total perception-reaction time and lane-changing time required by a driver. For determining the driver's perception-reaction time, we have used the driver's decision time in addition to the conventional 2.5 s of perception-reaction time for stopping sight distances. We have considered both the design speed and the average travel speed for the calculation of the length. To evaluate the accuracy of the new method, we have chosen four sites on expressways for which relatively high accident rates were recorded. As a result, we could verify that the current limit (240 m) was sufficient for drivers to be able to change lanes in the given specific geometry. However, the prescribed limit should be revised in case the drivers' decision time is considered to be their perception-reaction time. All new approaches for calculating the ideal length of a connector have been carried out by taking into account the design speed as well as the average travel speed. Owing to the characteristics of the specific geometry for two consecutive exit ramps and the large difference between the design speed and the average travel speed in the objective areas, it is more realistic to use the proposed method by keeping the decision time equal to a driver's perception-reaction time, in order to determine the ideal distance that should be maintained between two consecutive exit ramps.

• Proceedings of the Korean Society for Cognitive Science Conference
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• 2010.05a
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• pp.18-24
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• 2010

ADHD 아동의 주의장애 원인이 반응 결정에서의 억제의 미숙인지, 전반적인 주의 기능의 미숙인지 알아보기 정상아동과 ADHD 아동을 대상으로 flanker 과제를 실시하였다. 실험 1 에서는 방해자극과 목표자극의 일치 (3: 일치, 불일치, 중립), 방해자극과 목표자극의 SO (3: -100, 0, 100 ms), 집단 (2; 정상, ADHD)의 3 요인 실험을 실시하였다. 정상아와 ADHD 아동간에 반응시간에서는 차이가 없었다. 그러나 정상아동에 비해 ADHD 아동이 부정확 반응을 더 많이 하였다. 특히 방해자극이 100 ms 먼저 제시되기 시작하는 SOA -100 ms 조건에서 두 집단의 차이가 크게 나타났다. 이 결과가 반응결정 단계에서의 억제에서 비롯되는 것인지 알아보기 위해 실험 2 에서는 목표자극의 반응 set(좌, 우)에 포함되지 않는 방해자극(상, 하로향함)을 제시하는 무관련조건을 추가하여 실험을 실시하였다. 실험 1 과 같이 불일치조건에서는 정상아동에 비해 ADHD 아동이 오반응을 더 많이 산출하였다. 그러나 무관련조건에서는 정상아와 ADHD 아동 간에 오반응에서 차이가 없었다. 즉 두 집단 모두에서 중립조건보다 무관련 조건에서 반응시간은 길었으나, 오반응에서는 차이가 없었다. 즉 정상아와 ADHD 아동 모두 전반적인 주의에서는 차이가 없다는 것을 시사하였다. 두 실험의 결과는 정상아에 비해 ADHD 아동이 반응 결정 단계에서의 억제에서 차이가 나는 것을 시사하는 것으로 해석되었다.

• Annual Conference on Human and Language Technology
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• 1990.11a
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• pp.97-103
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• 1990

읽기시간과 재인기억을 통하여 스크립트에 부합되지 않는 정보가 어떻게 처리되는지 알아보았다. 실험 1에서는 문장을 읽고 문장 재인검사틀 하였다. 스크립트 비부합 문장의 읽기시간은 길고 재인 반응시간은 빨랐다. 실험 2, 3은 스크립트에 부합하지 않는 정보가 기억이 잘되는데, 그 이유가 노력의 결과로 다른 정보와 통합되었기 때문인지 아니면 비부합정보가 두드러졌기 때문인지 알아보려고 설계되었다. 실험 2에서는 명제쌍을 만들어 즉시 재인기억을 하였고, 실험 3에서는 피험자가 비부합정보를 충분하게 처리할 수 있도록 자기 속도(self-paced)로 읽고 명제쌍으로 지연재인검사를 했다. 비스크립트 정보와 전형적인 명제로 된 명제쌍이 전형적인 명제쌍보다 반응시간이 길었다. 이 결과는 스크립트 비부합정보는 자체로는 기억이 잘되나 다른 정보와 통합은 되지 않은 것으로 해석되었다.

• Korean Journal of Cognitive Science
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• v.20 no.3
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• pp.309-333
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• 2009

Two experiments were conducted to examine the role of Kulja and morpheme in processing two-syllable Sino-Korean words. In Experiment 1, the effects of morphemic frequency were not significant at the initial and final positions of a word while Kulja frequency and Kulja-morpheme correspondence at both positions in a word had a significant impact on the processing of nonwords. Lexical decision times were longer for nonwords with high frequency Kulja and for nonwords with ambiguous Kulja-morpheme correspondence whose Kulja can go with many different morphemes. In Experiment 2 Kulja-morpheme correspondence was examined for words as well as nonwords. Lexical decisions were slower for stimuli with ambiguous Kulja-morpheme correspondence. The effect was more stable for nonwords, which replicated the result of Experiment 1. In sum, the results of this study suggest that words with ambiguous Kulja-morpheme correspondence activate many different morphemes and competition among these morphemic candidates slows down the lexical selection process. Kulja frequency, Kulja neighborhood, morphemic frequency, morphological neighborhood, and Kulja-morpheme correspondence in Korean word recognition were also discussed.

• 한국ITS학회:학술대회논문집
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• v.2007 no.10
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• pp.111-117
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• 2007

• Korean Journal of Cognitive Science
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• v.23 no.2
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• pp.269-293
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• 2012

This study aimed to investigate the interactive effects of individual's cultural disposition (individualism, collectivism, horizontal disposition and vertical disposition) and cognitive style (analytic vs. holistic thinking) combination on differences in global precedence. For this purpose, the participants were divided into 4 different cultural disposition groups based on Singelis et al.'s(1995) INDCOL scale, and 2 cognitive style groups based on Choi et al.'s(2007) AHS, and required to respond selectively to global or local property of two types of compound stimuli (compound figure and compound letter). Reaction time and error rates for both global or local property were analyzed and compared as the dependent measurement. The results can be summarized as followings. First, faster responses were observed in compound figure condition than in compound letter condition, and to global property than to local property. Second, contrasting to individualism-cognitive style or horizontal disposition-cognitive style combinations, significant interaction effects both between collectivism and cognitive style, and between vertical disposition and cognitive style on global/local processing were found. This result indicated that combinations of collectivism-holistic thinking and vertical disposition-holistic thinking can induced larger global precedence effect than other combinations of cultural disposition and cognitive style.

• Transportation Technology and Policy
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• v.8 no.6
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• pp.55-61
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• 2011

• 한국ITS학회:학술대회논문집
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• v.2006 no.10
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• pp.249-253
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• 2006

• Korean Journal of Cognitive Science
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• v.5 no.2
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• pp.25-45
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• 1994

The presnt study investigated the effect of stimulus-response compatibility (S-R compatibility) on Hangul transcription typing. In this experiment, two condition were manipulated, the first was a low S-R compatibility condition in which consonants were typed with left hand and vowels with right hand; the second was a high S-R compatibility condition in which hands for consonants and vowels were reversed. Subjects were requested to type the letter presented on the screen as accurately and immediately as possible. It was found that the compatibility interacted with the vowel shape. That is, in the high S-R compatibility condition, the response time was shorter when letters of vertically- shaped vowel were typed than when those of horizontally-shaped vowel were typed. In the low S-R compatibility codition, however, the response time was shorter for letters of horizontally-shaped vowel than for those of vertically-shaped vowel.