• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2012.11a
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• pp.31-32
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• 2012

본 논문에서는 수렴형 양안식 카메라 배열에서 효율적으로 깊이 지도를 생성하는 방법을 제안한다. 기존의 양안식 영상에서의 깊이 지도 추출 방법은 영상 정렬화 과정이 필수적이었다. 이는 평행형 배열에서는 효과가 있지만, 수렴형 배열에서는 영상을 왜곡시키는 문제를 발생시킨다. 본 논문에서 제안하는 방법은 영상 정렬화 과정을 생략하고, 에피폴라 조건에 따라서 직접적으로 깊이 값을 추출한다. 깊이 예측을 위한 Markov Random Field 에너지는 계층적 구조를 사용하여 복잡도를 낮춘 상수 공간 신뢰 확산 방식에 의해서 최적화한다. 이어서 좀 더 정확한 깊이 지도를 구하기 위해서 후처리 기술을 최종적으로 적용한다. 실험을 통해 본 논문에서 제안한 방법이 기존의 방법에 비해서 적은 제약으로 깊이 지도를 좀 더 안정적으로 추출할 수 있음을 보였다.

• Journal of Korea Water Resources Association
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• v.41 no.10
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• pp.995-1007
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• 2008

Studies on modeling the rainfall-runoff relationship which shows nonlinear trend strongly use artificial neural networks theory not only for the prediction but also for the characteristics analysis of the data used by pattern classification. For the pattern classification, the results from Self-Organizing Map (SOM) mention that the map size and array for the SOM training have significantly influenced on the SOM performance. Since there is no deterministic method or theoretical equation to determine the number of rows and columns for the map size, hexagonal array is generally used for the map array. Therefore, this study present a determination of the optimized map structure for the rainfall-runoff analysis in Naju station considering the map size and array simultaneously which can represent the classified characterization of rainfall-runoff relationship. The result showed that the map size of 20$\times$16 hexagonal array with 8-clustered patterns was selected as an appropriate map structure for rainfall-runoff analysis in Naju station.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.6A
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• pp.458-463
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• 2012

In this paper, we propose a direct depth map acquisition method for the convergence camera array as well as the parallel camera array. The conventional methods perform image rectification to reduce complexity and improve accuarcy. However, image rectification may lead to unwanted consequences for the convergence camera array. Thus, the proposed method excludes image rectification and directly extracts depth values using the epipolar constraint. In order to acquire a more accurate depth map, occlusion detection and handling processes are added. Reasonable depth values are assigned to the obtained occlusion region by the distance and color differences from neighboring pixels. Experimental results show that the proposed method has fewer limitations than the conventional methods and generates more accurate depth maps stably.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.11
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• pp.2902-2912
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• 1994

The ultrasonic array sensor system, consisting of one transmitter and fourreceivers instead of the traditional combination of a transmitter and a receiver is proposed in order to identify the location of objects. From the theoretical analysis and the experimental results, it is found that this new array sensor system could derive the information on the position of objects accurately, while the traditional sensor system could provide only the informatioin on the distance to objects. This sensor system is used to develop a sonar-based local mapping algorithm. The local map is used to find the existence of possible gates, through which the mobile robots can pass, and to select the suitable one in order for the robots to reach the goal safely in the presence of obstacles. The performance of the proposed local map algorithm is demonstrated experimentally in a small working area with several obstacles. It is found that the quality of the resulting local map is sufficient for the avoidance of collisions between the robots and obstacles and for the selection of the suitable gate leading to the goal. It is also shown that the global map of the working area could be obtained by integrating several local maps constructed from different locations and that it matches the actual layout of the working area well.

• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.12
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• pp.105-110
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• 2016

To reduce the cost and volume of a digital camera, a subsampled color filter array(CFA) image is used and demosaicking is applied to estimate the missing color values. However, aliasing, the overlaps of signals in the frequency domain, occurs when signals are subsampled. This causes aliasing artifacts such as false colors and zipper effects in demosaicking processes. In this paper, the algorithm estimating high-quality color images by removing aliasing artifacts in them is proposed. The aliasing region map is estimated using the sub-sampled signals of the CFA image. By using the aliasing region map and the estimated luminance image, the least squares problem of the observation models is designed and aliasing artifacts are eliminated. The experiments demonstrate that the proposed algorithm restores color images without aliasing artifacts.

• School Mathematics
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• v.15 no.4
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• pp.889-920
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• 2013

The aim of this study is to look into the didactical background for introducing the concept of multiplication and teaching multiplication facts in elementary school mathematics and offer suggestions to improve teaching multiplication in the future. In order to attain these purposes, this study deduced and examined concepts of multiplication, situations involving multiplication, didactical models for multiplication and multiplication strategies based on key ideas with respect to the didactical background on teaching multiplication through a theoretical consideration regarding various studies on multiplication. Based on such examination, this study compared and analyzed textbooks used in the United States, Finland, the Netherlands, Germany and South Korea. In the light of such theoretical consideration and analytical results, this study provided implication for improving teaching multiplication in elementary schools in Korea as follows: diversifying equal groups situations, emphasizing multiplicative comparison situations, reconsidering Cartesian product situations for providing situations involving multiplication, balancing among the group model, array model and line model and transposing from material models to structured and formal ones in using didactical models for multiplication, emphasizing multiplication strategies and properties of multiplication and connecting learned facts and new facts with one another for teaching multiplication facts.

• School Mathematics
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• v.18 no.1
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• pp.175-191
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• 2016

In the elementary school mathematics textbook that has been revised in 2013, the instructional sequence for teaching addition and subtraction, which had remained unchanged for three decades since 1982, was finally changed in 2013. Particularly, the addition and subtraction of two-digit numbers without regrouping, such as 72+25=97 or 85-24=61, are taught earlier than the composing and decomposing of the number 10 using other numbers. This study examines the appropriacy and validity of these changes. However, the reason for these changes in the national curriculum or teacher's guide could not be determined. Further, several references emphasize the addition of two single-digit numbers, such as 7+8=15, and the subtraction of a single-digit number from a number between 11 and 19, such as 16-9=7, as basic facts. In other countries' textbooks, the teaching of addition and subtraction up to the number 20 is prioritized before teaching the addition and subtraction of two-digit numbers without regrouping. The results of this study indicate that these changes in the instructional sequence in the textbook that was revised in 2013 need to be reconsidered.

• The Science & Technology
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• v.33 no.5 s.372
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• pp.68-73
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• 2000

10여년간에 걸쳐 30억달러의 자금이 투입된 인간게놈계획사업(genome project)은 유전자의 배열상태를 우선 밝히는 역사적인 작업을 마무리했다. 2000년 3월 14일에는 클린턴 미국대통령과 블레어 영국수상이 그동안의 인간게놈계획의 연구결과를 전 세계 과학자들에게 무료로 공개한다고 발표하여 세계과학자들의 기대를 부풀게 했다. 그러나 30억 이상의 유전정보를 해독하는 사업은 이제 겨우 시작에 지나지 않다는 것도 사실이다. 인간게놈의 배열을 가려내는 것은 사전으로 비유할 때 모든 낱말의 알람표를 만들었을 뿐이며 그 낱말들(배열)이 무슨 뜻을 갖고 있는 것인지 밝히는 일은 지금부터 풀어야 할 과제이다. 세계 주요 의약계는 먼저 인간게놈에 내포된 10만개 이상의 유전자가 어떤 기능을 갖고 있는가 해독하는데 필요한 툴(연장)을 고안하여 유전자에서 얻는 지식을 이용하여 신약을 개발하는 불꽃튀는 경쟁에 뛰어 들었다. 그러나 이것은 간단한 일이 아니다. 신약개발에는 평균 15년이란 오랜 세월이 걸리고 당초의 유효성분의 발견이 약으로써 상품화되는 비율은 5% 이하다. 잠재적인 신약후보는 독성부작용을 알아보기 위해 동물을 이용한 생물학적 검사와 수년간에 걸친 인간에 대한 임상실험을 거쳐야 한다. 아무리 게놈기술이 탁월하다고 해도 이 과정을 단축시킬 방법이 없다. 그러나 게놈프로젝트의 열매가 우리의 의학 및 약학발전사에 중대한 이정표를 세울 것만은 틀림없다. 세계의 대표적인 연구기관을 통해 2050년까지의 의약발전상을 미리 내다본다.

• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.1380-1384
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• 2010

현재 환경부에서는 수질오염총량관리제를 위하여 각 단위유역의 말단지점에서 8일 간격으로 수질 및 유량을 측정하고 있으며, 이 자료들을 공개하고 있다. 이러한 양질의 자료의 활용성을 제고하기 위해서는 무엇보다도 자료의 분석을 위한 다양한 기법이 개발되고 제안되어야 한다. 따라서 본 연구에서는 수질 및 유량자료를 동시에 적용하여 두 자료 사이의 관계를 조사하고 특성을 파악하기 위하여 자기조직화 특성지도(Self-Organizing Feature Map: SOFM) 이론을 적용하였다. 시행착오법에 의해 적정한 SOFM 구조를 결정하였으며, 그 결과 $4{\times}4$ 구조의 육각형 배열을 갖는 구조를 이용하였다. SOFM에 의해 분류된 3개의 패턴 중 패턴-1은 유량자료의 크기에 의해 분류되었고, 패턴-2와 패턴-3은 BOD 농도의 크기에 따라 분류된 것으로 파악되었다. 따라서 SOFM의 적용에 의한 자료의 분류를 수행하고, 그 분류기준을 파악할 경우 SOFM의 자료 분석 도구로서의 활용성이 더욱 높아질 것으로 판단된다.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10a
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• pp.119-124
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• 1993

This paper describes a method of producing maps of an indoor environment with an autonomous mobile robot equipped with sonar array. This method uses the certainty grid suitable for accommodation of inaccurate sensor data and real-time navigation. Each grid contains a certainty vale that indicates the measure of confidence that an obstacle exists within th grid area. The scheduled firing method is used to eliminate the crosstalk between ultrasonic sensors. The effectiveness of the method is verified by a series of experiments.