• 한국조경학회지
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• 제35권1호
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• pp.28-35
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• 2007

The purpose of this study is to evaluate the visual preference factors for river scenery, which can vary according to changes in water levels, to estimate the optimal ratio of water surface/river width. Five locations on the Youngsan and Sumjin Rivers were selected as representative samples and field survey data such as channel geometry with water levels were prepared to develop the slide of river scenery, To estimate the level of satisfaction in river scenery, slides of 4 different water levels at each of the representative locations were developed through questionnaire. To analyse the correlation between the visual preference for river scenery and preference factors, a multi regression analysis method was adopted in this study. According to the results of the multi regression analysis, Factor B(Aesthetic factors) have the greatest affect on visual preferences and Factor A(A Feeling of Open space and Physical factors) affect significantly to visual preferences for river scenery. The results of analysis shows that the most preferred W/B ratio varies from 0.5 to 0.7 and this result indicates that many people prefer high levels river flow to maintain a natural and harmonious view of rivers. The results of this study will contribute to the field of river landscape design and river restoration projects in order to maximize the human being's satisfaction as a part of nature.

• 한국수학교육학회지시리즈C:초등수학교육
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• 제26권3호
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• pp.125-140
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• 2023

초등학교 수학에서 분수의 연산은 매우 중요하지만 학생들이 어려워하는 개념이다. 분수 연산의 기초가 되는 동분모 분수의 덧셈과 뺄셈에 대하여 현행 2015 개정 교육과정에 따른 국정 교과서 1종, 검정 교과서 10종을 분석하여 단원의 차시 흐름과 시각적 표현을 분석하였다. 분석결과, 각각의 교과서마다 나름의 순서와 차시 주제를 고민하여 단원을 구성하고 있었으며 비교적 충실하게 교육과정을 반영하였다. 또한, 각각의 교과서마다 사용하는 시각적 표현의 종류와 개수가 다르게 나타났으며 이는 분수의 연산 학습을 돕기 위하여 시각적 표현의 일관성 또는 다양성을 의도한 것으로 보인다. 각 교과서의 차시 구성 및 시각적 표현의 특성을 파악한다면 더욱 효과적으로 분수의 연산을 지도할 수 있을 것이다.

• 한국전산유체공학회지
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• 제8권1호
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• pp.30-37
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• 2003

The post-processor for two-dimensional flow visualization has been developed by using OOP(object-oriented programming) of Visual C++. User-friendly GUI(graphic user interface) has been built on the base of MFC(Microsoft Foundation Class). The number and order of variables can be specified by user because the input style is the free-format. The new variable can be defined and added to the variable list by using the various operators and functions.

• 한국지하수토양환경학회지:지하수토양환경
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• 제17권3호
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• pp.39-48
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• 2012

Visual MODFLOW, a three dimensional groundwater flow model, was used to analyze effects of a weir construction in an alluvial stream on the nearby groundwater flow system. A hypothetical conceptual model was developed to investigate how the groundwater level and the water budget could change after a weir construction depending on the location of tributary streams. A site example, dealing with the Juksan weir installed in the Yeongsan River, was also demonstrated to predict the effects of the weir construction. Model results show that impacts of a weir construction on the groundwater flow system greatly vary depending on how far a tributary is located and whether it is located downstream or upstream from the weir. Therefore, consideration of the location of tributaries in planning the location of a weir could effectively minimize the impacts of a weir construction on the groundwater flow system. It is also demonstrated that model results are highly dependent upon how the model is dealing with small tributaries and agricultural drainage channels, which can be easily found nearby the main streams, acting as major water bodies for groundwater discharge. The model for the Juksan area shows that the weir construction will change the direction of groundwater flow in some areas, leading to changes of groundwater quality and interaction of the Yeongsan River to the aquifer from a gaining to a losing stream. The model also predicted the areas where rise of groundwater level caused by the Juksan weir could adversely affect plant growth, and thereby suggested installing new drainage channels as a countermeasure to drawdown the groundwater level.

• Ocean Systems Engineering
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• 제7권1호
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• pp.39-51
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• 2017

Fishes detect various sensory stimuli, which may be used to direct their behavior. Especially, the visual and water flow detection information are critical for locating prey, predators, and school formation. In this study, we examined the specific role of these two different type of stimulation (vision and vibration) during the obstacle avoidance behavior of carp, Cyprinus carpio. When a visual obstacle was presented, the carp efficiently turned and swam away in the opposite direction. In contrast, vibration stimulation of the left or right side with a vibrator did not induce strong turning behavior. The vibrator only regulated the direction of turning when presented in combination with the visual obstacle. Our results provide first evidence on the innate capacity that dynamically coordinates visual and vibration signals in fish and give insights on the novel modulation method of fish behavior without training.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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• pp.53-53
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• 2002

According to glowing computing capacity, software in remote sensing has supported diverse processing interfaces from batch interface to high-end user interactive interface. In this paper, component based visual modeler is developed to process batch jobs for high-end users as well as novices. Visual modeler arranges several node groups which are categorized according to their purposes. These nodes carry out elemental unit processes and can be grouped to model. The model represents user specified job which is composed diverse nodes. User can organize models by connecting diverse nodes according to data flow model specification which rules node's connectivity and direction, etc. Furthermore, user defined models can be together to organize much more complex and large model.

• 전자공학회논문지
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• 제52권8호
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• pp.132-139
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• 2015

카메라를 이용하는 시각(visual) SLAM(Simultaneous Localization And Mapping)은 로봇의 위치 등을 파악하는데 널리 이용되고 있다. 일반적으로 시각 SLAM은 움직임이 없는 고정된 특징점을 대상으로 연속적인 시퀀스 상에서 카메라의 움직임을 추정한다. 따라서 이동하는 객체가 많이 존재하는 상황에서는 안정적인 결과를 기대하기 어렵다. 본 논문에서는 이동 객체가 많은 상황에서 스테레오 카메라를 이용한 SLAM을 안정화하는 방법을 제안한다. 먼저, 스테레오 카메라를 이용하여 깊이영상을 추출하고 옵티컬 플로우를 계산한다. 그리고 좌우 영상의 옵티컬 플로우를 이용하여 시차변화(disparity change)를 계산한다. 그리고 깊이 영상에서 사람과 같이 움직이는 객체에 대한 ROI(Region Of Interest)를 구한다. 실내 상황에서는 벽과 같은 정적인 평면들이 움직이는 영역으로 잘못 판단되는 경우가 자주 발생한다. 이런 문제점을 해결하기 위해 깊이 영상을 X-Z 평면으로 사영하고 허프(hough) 변환하여 장면을 구성하는 평면을 결정한다. 앞의 과정에서 판단된 이동 객체 중에서 벽과 같은 장면 요소를 제외한다. 제안된 방법을 통해 정적인 특징점이 요구되는 SLAM의 성능을 보다 안정화할 수 있음을 확인하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년 학술대회 논문집 정보 및 제어부문
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• pp.434-436
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• 2006

In a visual driver-assistance system, separating moving objects from fixed objects are an important problem to maintain multiple hypothesis for the state. Color and edge-based tracker can often be "distracted" causing them to track the wrong object. Many researchers have dealt with this problem by using multiple features, as it is unlikely that all will be distracted at the same time. In this paper, we improve the accuracy and robustness of real-time tracking by combining a color histogram feature with a brightness of Optical Flow-based feature under a Sequential Monte Carlo framework. And it is also excepted from Tracking as time goes on, reducing density by Adaptive Particles Number in case of the fixed object. This new framework makes two main contributions. The one is about the prediction framework which separating moving objects from fixed objects and the other is about measurement framework to get a information from the visual data under a partial occlusion.

• International Journal of Fluid Machinery and Systems
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• 제4권1호
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• pp.140-149
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• 2011

For a certain operating point of a horizontal shaft bulb turbine (i.e. volume flow, net head, blade angle, guide vane angle) the efficiency for different pressure levels (i.e. different Thoma-coefficient ${\sigma}$) is calculated using a commercial Computational Fluid Dynamics (CFD-)-code including two-phase flow and a cavitation model. The results are compared with experimental results achieved at a closed loop test rig for model turbines. The comparison of the experimentally and numerically obtained efficiency and the visual impression of the cavitation show a good agreement. Especially the drop in efficiency is calculated with satisfying accuracy. This drop in efficiency in combination with the visual impression is of high practical importance since it contributes to determine the admissible cavitation in a bulb-turbine. It is seen that the incipient cavitation in Kaplan type turbines has no major importance in determing this admissible amount of cavitation.

• 태양에너지
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• 제15권2호
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• pp.39-46
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• 1995

본 논문은 가는 철사를 삽입한 이상의 초소형 열사이폰에서의 작동유체의 유동과 그 열전달 특성 및 가시화에 대한 연구 결과를 소개하고자 한다. 가시화 실험은 열사이폰 내의 작동유체의 이상유동 현상을 확실히 보여주었으며, 또한 삽입한 철사의 직경, 증발과 냉각부분의 길이의 비, 그리고 증발부에 가해진 열량이 열사이폰의 열성능에 미치는 영향에 대하여 정량적으로 그 결과를 분석하였다.