• 대한수학교육학회지:학교수학
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• 제18권1호
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• pp.175-191
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• 2016

본 연구는 2009 개정 교과서에서 제시하고 있는 자연수 덧셈과 뺄셈의 지도 순서를 비판적으로 검토한 것이다. 2009 개정 교과서에서는 제4차 교육과정기부터 2007 개정 교육과정기까지의 교과서에서 제시하고 있는 자연수 덧셈과 뺄셈의 지도 순서와는 다르게, 받아올림이 없는 두 자리 수의 덧셈과 받아내림이 없는 두 자리 수의 뺄셈의 지도순서를 상당히 앞으로 당겼고, 10을 가르기와 모으기는 상대적으로 뒤로 미뤘다. 이에 본 연구에서는 이러한 덧셈과 뺄셈 지도 순서의 변화가 어떠한 근거에 의한 것인지 찾아보고자 하였다. 여러 문헌과 외국 교과서에서 제시하고 있는 덧셈과 뺄셈 지도 순서를 살펴본 결과 받아올림이나 받아내림이 없는 (몇십 몇)${\pm}$(몇십 몇)을 (몇)+(몇)=(십 몇)과 (십 몇)-(몇)=(몇)에 앞서 지도하는 경우는 찾기 어려웠다. 오히려 20 이하의 덧셈과 뺄셈을 강조하며 받아올림과 받아내림의 학습에 앞서 지도하는 경우가 많았다. 이러한 결과는 차기 교과서 집필에서 덧셈과 뺄셈 단원 및 차시 내용을 배열함에 있어, 세심한 고려가 필요함을 시사한다.

• 대한방사선기술학회지:방사선기술과학
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• 제42권5호
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• pp.351-356
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• 2019

This study aimed to determine whether there was a difference in measurements between North American Symptomatic Carotid Endarterectomy Trial(NASCET) and Warfarin-Aspirin Symptomatic Intracranial Disease(WASID) methods that measure the middle cerebral artery stenosis in Digital Subtraction Angiography (DSA) and Magnetic Resonance Angiography (MRA). It involved 24 patients who had completed both DSA and MRA among patients with Middle Cerebral Artery (MCA) stenosis. The Middle Cerebral Artery (MCA) stenosis was measured using the NASCET and WASID methods through a retrospective analysis. For the NASCET and WASID methods, they performed measurements on normal blood vessels located far from and close to the stenosis, respectively. The mean value and standard deviation of the Digital Subtraction Angiography (DSA) measured by the NASCET method were 59.23% and 13.27%. On the other hand, those of the Digital Subtraction Angiography (DSA) measured by the WASID method were 66.64% and 12.47%. And, the mean value and standard deviation of the Magnetic Resonance Angiography (MRA) measured by the NASCET method were 49.82% and 12.06%. By contrast, those of the Magnetic Resonance Angiography (MRA) measured by the WASID method were 56.63% and 10.67%. All the p-values obtained by the Pearson and Spearman correlation tests in the Digital Subtraction Angiography (DSA) and the Magnetic Resonance Angiography (MRA) were <0.01. In conclusion, this study suggests that both the NASCET and WASID methods to measure the middle cerebral artery stenosis in the Digital Subtraction Angiography (DSA) and the Magnetic Resonance Angiography (MRA) can be used if they are not used interchangeably.

• 한국디자인학회:학술대회논문집
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• 한국디자인학회 2001년도 디자인학연구 2001 봄 학술발표회 논문집
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• pp.20-21
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• 2001

• Imaging Science in Dentistry
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• 제32권3호
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• pp.147-151
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• 2002

Purpose: To compare the standard deviation of gray levels on digital subtracted images obtained by different dental subtraction programs. Materials and Methods: Paired periapical films were taken at the lower premolar and molar areas of the phantoms involving human mandible. The bite registration group used Rinn XCP equipment and bite registration material, based on polyvinyl siloxane, for standardization. The no bite registration group used only Rinn XCP equipment. The periapical film images were digitized at 1200 dpi resolution and 256 gray levels by a flat bed scanner with transparency unit. Dental digital subtraction programs used for this study were Subtractor (Biomedisys Co., Korea) and Emago (Oral Diagnostic Systems, The Netherlands). To measure the similarities between the subtracted images, the standard deviations of the gray levels were obtained using a histogram of subtracted images, which were then analyzed statistically. Results: Subtracted images obtained by using the Emago program without manual selection of corresponding points showed the lowest standard deviation of gray levels (p<0.01). And the standard deviation of gray levels was lower in subtracted images in the group of a bite registration than in the group of no use of bite registration (p < 0.01). Conclusion: Digital radiographic subtraction without manual selection of reference points was found to be a convenient and superior method.

• 한국음향학회지
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• 제18권1호
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• pp.38-44
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• 1999

본 연구에서는 단일 채널 단구간 진폭 스펙트럼 추정 기법의 하나인 Spectral Subtraction 방법과 2 채널 Griffiths-Jim Beamformer를 결합한 음성 강조기법을 제안한다. 기존의 단구간 진폭 스펙트럼 추정 기법에서는 관측된 신호의 스펙트럼에서 잡음의 평균 스펙트럼을 감산하여 잡음을 제거하고 있지만, 이 방법을 이용하여 잡음을 제거 할 경우에는 잡음 변동시 잡음 억제 능력이 미약하고, 목적 신호의 단구간 진폭 스펙트럼 추정 성능이 낮아진다는 단점을 갖고 있다. 그 이유는 실제 잡음의 스펙트럼은 평균값 주위에 분산되어 있기 때문이 다. 그러므로, 2 채널 Beamformer의 사각(Blocking Matrix)를 이용하여 분석 구간에서의 잡음의 단구간 진폭 스펙트럼을 추정하고, 이 추정된 값을 이용하여 목적 신호의 스펙트럼을 추정하는 기법을 제안하고, 컴퓨터 시뮬레이션을 통하여 그 유효성을 입증한다.

• 정보과학회 컴퓨팅의 실제 논문지
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• 제24권3호
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• pp.151-156
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• 2018

본 연구는 영상 분석에서 최근 좋은 연구 성과를 내고 있는 컨볼루션 신경망 (Convolutional Neural Network: CNN) 기법을 실외 CCTV 영상 분석에 적용하여 객체 유형을 분류하는 방법론은 제안한다. 배경 차분 (background subtraction)을 사용하여 찾고자 하는 객체 후보들을 추출해내고 이를 CNN을 이용해 분류함으로써 계산량을 줄이는 효과를 얻는 방법이다. CNN 학습용 CCTV 영상 수집을 위해 범죄 발생이 주로 일어나는 골목길, 놀이터 등에서 촬영한 CCTV 영상 DB를 구축하였으며 우선적으로 사람인 객체만 검출하는 분류기를 학습하였다. 다양한 학습 데이터 사이즈와 세팅에 맞게 실험하였으며 실험 결과 약 80%의 분류 정확도를 보였으며 새로운 CCTV 영상으로 테스트했을 때 약 67.5%의 성능을 보였다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제8권6호
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• pp.1946-1963
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• 2014

Most background subtraction methods focus on dynamic and complex scenes without considering robustness against noise. This paper proposes a background subtraction algorithm based on dictionary learning and sparse coding for handling low light conditions. The proposed method formulates background modeling as the linear and sparse combination of atoms in the dictionary. The background subtraction is considered as the difference between sparse representations of the current frame and the background model. Assuming that the projection of the noise over the dictionary is irregular and random guarantees the adaptability of the approach in large noisy scenes. Experimental results divided in simulated large noise and realistic low light conditions show the promising robustness of the proposed approach compared with other competing methods.

• 대한한의학원전학회지
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• 제28권2호
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• pp.103-114
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• 2015

Objectives : The publication year(1608) of Euilinchwalyo is very closed to the year(1610) of Dongeuibogam, so several researches indicate that Dongeuibogam was influenced by Euilimchwalyo. We, authors have recently focused on the way to quote books in Dongeuibogam and found particular aspects in the way of quotation between Euilimchwalyo and Dongeuibogam. Methods : 1. Comparing the contents of Sosokmyeongtang in quotation books between Euilimchwalyo and Dongeuibogam. 2. Tracing the origin of Sosokmyeongtang and comparing chief virtue, consist of herbal medicine, way of dose and making and the method of addition and subtraction in Sosokmyeongtang. Results : Beijiqianjiyaofang was the origin book that recorded Sosokmyeongtang but there was no methods of addition and subtraction. After Jin and Yuan dynasty, the books, which had Sosokmyeongtang, started to record the methods of addition and subtraction in Sosokmyeongtang. However, even though Euilinchwalyo also recorfed the methods of addition and subtraction in Sosokmyeongtang such as other medical books, Dongeuibogam didn't keep that way to document up. Conclusions : The fact that Dongeuibogam was influenced by Euilimchwalyo means 2 ways. The first is that Dongeuibogam was influenced by Euilimchwalyo directly. The second is that Heo Jun, who wrote Dongeuibogam, tried not to duplcate or follow Euilimchwalyo somehow.

• 한국실내디자인학회논문집
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• 제25권2호
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• pp.3-12
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• 2016

Aires Mateus Architects is one of the most well-known Portuguese architects after $\acute{A}lvaro$ Siza and Eduardo Souto de Moura. The studio shows clear design methods in which the relationship between solid mass and void space are creatively inter-connected. Subtractive transformation of form is the fundamental aspect of this relationship. Most of Aires Mateus' projects were designed based on the subtractive method. Although subtraction can be seen as architectural formal presentation, in Aires Mateus' cases, there are deeper logics, strategies, and meanings. Not only to create a form, subtractive method has been flexibly used to organize and compose different programs and spatial atmosphere. To examine this hidden dimension of Aires Mateus' unique design process, 5 case projects were selected and analyzed in detail based on program, light & visual-perception, and site's placeness. From the case study results, it is found that there are much deeper role of subtraction: relationship between solid-void are constantly changing to generate serviced and servant spaces, there are central spaces that are contrast against the complexity of exterior forms, aiming to build an archetypal form that transcends ever-changing time, ambivalent balance between universality and peculiarity in the genealogy of contemporary architecture. The study concluded that the unique characteristics of subtraction method as design organization have various possibilities that can apply on other architectural and interior projects which would have similar ideas and circumstances.

• 한국정보전자통신기술학회논문지
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• 제6권2호
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• pp.81-87
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• 2013

Motion segmentation is a fundamental technique for analysing image sequences of real scenes. A process of identifying moving objects from data is a typical task in many computer vision applications. In this paper, we propose motion segmentation that generally consists from background subtraction and foreground pixel segmentation. The Approximated Median Filter (AMF) was chosen to perform background modeling. Motion segmentation in this paper covers RGB video data.