• Science of Emotion and Sensibility
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• v.6 no.3
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• pp.1-11
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• 2003

The purpose of the present driving simulation study was to examine the effect of cellular-phone use on driving performance when required driving speeds were systematically varied(60, 80, 100, or 120km/h) while either using cellular-phones(experimental condition; Hands-Free or Hands-Held) or not(control condition). Driving performance was measured both by longitudinal vehicle control(i.e., variabilities in driving speed and headway) and lateral vehicle control(variabilities in lane position). The results can be summarized as followings: (1) The significant difference in driving speed variation between the two cellular-phone usage conditions was found only at relatively higher driving speed conditions(i.e., over 80km/h). (2) Only in the experimental condition where cellular-phone was required to be used while driving, the magnitudes of variation in driving speed, headway and lane position were gradually increased as the required driving speeds were increased(this tendency was not found in control condition). And. (3) the dependent measures of this study appeared to suggest that cellular-phone usage itself (rather than the types of cellular-phone) had significant impact on driving performance. Finally, implication and issues related to this study were discussed.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.1
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• pp.175-183
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• 2014

This study investigates the response of structures to tunnelling-induced ground movements in clay ground, varying tunnel excavation condition (tunnel depth and diameter), tunnel construction condition (ground loss), and tunnel ground condition (soft clay and stiff clay). Four-story block-bearing structures have been used because the structures can easily be characterized of the extent of damages with crack size and distribution. Numerical parametric studies have been used to investigate of the response of structures to varying tunnelling conditions. Numerical analysis has been conducted using Discrete Element Method (DEM) to have real cracks when the shear and tensile stress exceed the maximum shear and tensile strength. The results of structure responses from various parametric studies have been integrated to consider tunnel excavation condition, tunnel construction condition, and tunnel ground condition and provide a relationship chart among them. Using the chart, the response of structures to tunnelling can easily be evaluated in practice in clay ground.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.2
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• pp.681-687
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• 2013

This study examined whether the combination of the indoor temperature on the learning environment and the colors of the learning materials affect the learning performance. To do this, the condition of indoor temperature was divided into three conditions: the neutral condition which is the appropriate temperature condition of the learning activities ($22.5{\sim}24^{\circ}C$), the high-temperature condition (> $24^{\circ}C$), and the low-temperature condition (< $22.5^{\circ}C$). In addition, colors of red, blue, black, and green were used as the warm, cold, and neutral colors, and the verbal-working memory task was used as the learning task. As a result, it was not significant differences in the response time of the learning task, whereas, in the accuracy rate of the learning task, the performance was more accurate in red- and black-color conditions. These results could be interpreted as the saliency and color-temperature of the red color, and the familiarity and specificity of the black color.

• The Journal of Engineering Research
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• v.6 no.1
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• pp.5-14
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• 2004

Finding a solution to a constraint satisfaction problem requires choosing values for variables so as to satisfy the constraints of the problem. A constraint is simply a logical relation among several unknowns (or variables), each taking a value in a given domain. Conventional constraint-based scheduling systems are not enough to satisfy the all constraints because there are conflicts between them. In this paper, we propose a method for interactive scheduling, which have two major problems: first, it is hard to satisfy concretely all various kinds of constraints, and second, the search space is extremely large and requires a long execution time. To solve the above problems, we introduce the Interactive Scheduling System (ISS) that interacts with the user to exchange suggestions each other. Our system is performed in two steps: knowledge base generation of an initial assignment and iterative improvement with the user(host or internet client) to satisfy the constraints. Applying our system, we actually constructed timetables for our university, where the scheduling time is considerably reduced.

• 한국HCI학회:학술대회논문집
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• 2007.02b
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• pp.497-503
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• 2007

학습의 깊이의 단계를 Bloom은 지식, 이해, 적용, 분석, 종합, 평가라는 6가지의 단계로 나누면서 피상적인 학습과 감이 있는 학습으로 구분하였다. 최근 학습은 면대면 학습에서 뿐 아니라, 웹기반의 학습에서도 피상적인 학습 위주로 이루어진다는 비판을 받고 있고, 웹기반 학습에서는 자기조절 흑은 자기규제의 문제가 가장 큰 문제로 지적 받고 있다. 본 연구에서는 이를 해결하기 위한 방안으로서 감이 있는 학습을 촉진하고, 자기 조절을 촉진하는 메타인지를 웹기반학습에의 인터페이스 디자인에 적용하는 문제를 살펴보았다. 이를 알아보기 위해 메타인지 전략의 가장 핵심 요소인 '자기 점검'의 요소 중 학습 내용들 간의 위계 관계를 보여주는 지도 (MAP) 와 계획세우기를 도와주는 요소 (PLAN)를 기존 연구를 토대로 웹기반의 학습의 인터페이스로 구현하고, 이러한 요소들이 학습, 특히 Bloom이 말한 김이 있는 학습을 촉진하는지를 실험을 통해 살펴보았다. 메타인지를 활용한 웹기반 학습의 효과는 배운 내용의 사후 테스트 점수로 측정되었다. 일반적으로 웹상에서 이루어지는 학습의 일반적인 형태인 학습 중에 확인문제를 푸는 조건 (OX조건)과 확인문제와 학습 내용들 간의 위계 관계를 보여주는 지도를 제시하는 조건 (MAP조건), 이에 덧붙여 사전 계획세우기까지 모두 하는 조건 (PLAN조건)으로 나누어 실험이 진행되었다. 그 결과 첫째, 집단 간 참가자들의 전체적인 학습 점수는 MAP조건이 가장 낮고, OX조건이 중간, PLAN조건이 가장 높은 모습을 보였다. 그러나 이 차이가 통계적으로 유의미하지는 않았다. 또한 모든 조건의 집단에서 행해졌던 학습 중간의 OX점수는 집단별 점수의 차이가 통계적으로 유의미하지는 않았으나, 평균의 차이를 보여주었다. 둘째, 조건별 참가자의 학습 효과는 피상적인 학습수준(암기)에서는 통계적으로 집단 간 유의미한 차이를 보였다. 그러나 감이 있는 수준의 학습(문제해결)에서는 집단 간에 통계적으로 유의미한 학습의 차이를 보이지 않았다. 따라서 깊이있는 학습을 촉진하는 웹기반 학습의 인터페이스 디자인에 대해서는 추후 연구가 필요하다.

• Journal of Korea Water Resources Association
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• v.38 no.11
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• pp.955-962
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• 2005

Even though the runoff volume is very sensitive to the antecedent soil moisture condition (AMC), the general rainfall-runoff analysis in Korea has accepted, without careful consideration of its applicability, the AMC classification of the Soil Conservation Service (SCS, 1972). In this study, by following the development procedure of SCS Curve Number (CN), the rainfall-runoff characteristics of the Jangpyung subbasin of the Pyungchang River Basin were analyzed to estimate the CN and evaluate the AMC classification of currently being used. As results, CN(I), CN(II), and CN(III) were estimated to be 72.1, 79.3, and 76.7, respectively. Among them CN(II) was found to be similar to the other reports but the other two were totally different from those of theoretically estimated. However, it is difficult to evaluate the AMC with CN, rather the frequency of each AMC could be a better indicator for its validity. This study developed the histogram of AMC and compared the frequency of each AMC. hs results we found that the criterion for AMC-III should be increased, Hut that for AMC-I decreased.

• Korean Journal of Logic
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• v.22 no.1
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• pp.183-209
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• 2019

In this paper, I first examine Reiss'(2005) arguments for the causal instrumental variable. Second, I argue that the conditions for causal transitivity I consider meet what the causal instrumental variables and the interveners of the manipulation theory of causation are intended to hold. Reiss shows that two conditions for instrumental variables are not sufficient for causal significance of independent variables for dependent variables. Reiss articulates and reformulates the conditions for instrumental variables in terms of the conditions on causality, while naming his instrumental variables as causal instrumental variables. Reiss argues that the causal instrumental variables are similar to the interveners of the manipulation, or intervention theory of causation. He further argues that the causal instrumental variables do a better job the interveners do. I argue that the conditions for causal transitivity I consider meet the goal the conditions for the causal instrumental variables and the conditions for the interveners both are intended to achieve.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.150-150
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• 2015

최근 하천의 수위조절 기능을 수행하는 보 건설이 증대되고 있다. 보는 원활한 용수공급을 위해 필수적인 구조물이지만, 하천 횡단 구조물의 특성상 유사퇴적에 의한 통수단면적 감소, 홍수위험도 증가, 수질악화 등의 문제를 내포하고 있다. 이를 해결하기 위해 유사시 유사배출이 가능하고 수문개도를 통한 통수단면적 조절로 홍수위험도를 감소시킬 수 있는 가동보를 고정보와 병용해서 적용하는 추세이다. 가동보는 수문 운영 방식에 따라 하류의 흐름상태가 다양하게 나타나며, 흐름 상태에 따라 하도 및 구조물에 미치는 영향도 달라진다. 그러나 기존 가동보 및 보 하류 구조물의 설계 시 일반적으로 수문 운영조건을 고려하지 않고, 홍수위 조건을 최악조건으로 고려하는 한계가 있다. 본 연구에서는 3차원 수치모델(FLOW-3D)을 활용하여 가동보의 운영에 따라 발생하는 다양한 흐름조건이 보 하류에 미치는 영향을 검토하고자 한다. 수치모델의 검증을 위해 기존 수행된 수리실험과의 비교를 수행하였고, 홍수위 조건(수문 전문개도) 및 관리수위 조건(수문 일부개도)에서 수치모의를 수행하였다. 보 상류, 직하류, 도수종점에서 발생하는 단면최대유속, 바닥전단 응력, Froude 수 등의 수리특성을 분석하였고, 상하류간 수심차와 수문개도높이의 비와 접근유속과 보 직하류에서 유출되는 유속의 비로 무차원화하여 관계를 분석하였다. 또한 홍수위 조건과 관리수위 조건에서 발생하는 수리특성을 비교함으로써, 보 하류부 구조물 설계 시 반영할 최악조건을 예측하고, 수문운영이 하류부에 미칠 수 있는 영향을 가시적으로 확인할 수 있었다. 향후 상류의 유량조건 및 상하류 수위차에 따른 가동보의 운영조건이 보 하류의 안정성 지표산정에 활용될 수 있기 위해 보다 심도있는 연구 수행이 필요하다.

• Korean Journal of Logic
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• v.21 no.3
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• pp.321-352
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• 2018

This paper is intended to examine a relationship between the Principal Principle and Conditionalization. For this purpose, I will first formulate several versions of the Principal Principle and Conditionalization in Section 2. In regard to the relationship between the two norms in question, I will show in Section 3 that the Principal Principle and Conditionalization are complementary in two particular senses. The first complementarity is that we don't have to formulate every version of the Principal Principle if the credences evolves by means of Conditionalization. The second complementarity is that we don't have to require for rational agents to update overall credal state by means of Conditionalization if the agent satisfies the Principal Principle. This result can be regarded as a result that criticizes and supplements some existing works about the relationship between the norms.

• Journal of the Korean Magnetics Society
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• v.6 no.1
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• pp.21-27
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• 1996

The effects of various manufacturing conditions on the characteristics of metal particle tape using ultra-fine metal powder were investigated. As functions of kneading conditions and milling solid contents. coating thickness, orientation, calender and curing conditions. various properties of the tapes were studied. By the consideration of physical and eletromagnetic properties of the tapes, optimum process conditions were determined. As a result of above investigations, we concluded that manufacturing processes were very important factor in addition to dispersion behavior of particles for achieving maximum properties of the metal particle tape.