• 한국정보통신학회논문지
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• 제14권9호
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• pp.1972-1978
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• 2010

AAM(Active Appearance Model)은 변형 가능한 형태의 검출에 가장 효과 적인 방법의 하나이며, 수학적으로 최적화 문제이다. 비용함수는 최소자승 함수이어서 볼록 함수이나, 탐색 공간이 볼록공간이 아니므로 국소 최소값이 전역 최소값인 것으로 보장 되지 않는다. 즉 초기값이 전역 최소값 근방에서 출발하지 않으면, 지역 최소값에 수렴하여 정확한 얼굴 윤곽 검출이 어려워진다. 본 논문에서는 연속적인 입력영상에 SIFT(Scale Invariant Feature Transform)와 유전자 알고리즘을 사용하여 눈동자를 검출하고 AAM 모델의 초기화 정보로 사용함으로써 조명과 배경에 강인한 AAM 기반의 얼굴 정합 방법을 제안한다. 실험을 통하여 제안한 AAM 기반 얼굴 정합 방법이 자세, 얼굴 배경 등에 대해 기존의 AAM 기반 얼굴 정합 방법보다 더 강인한 것으로 확인 되었다.

• 전자공학회논문지CI
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• 제46권1호
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• pp.128-135
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• 2009

동영상에서 시공간상 일정한 위상을 갖는 윤곽선을 정합시켜 물리적 공간에서의 동일한 위치를 추적하는 방법은 명암이 일정한 윤곽선을 정합시키거나 일정한 명암을 전제로 추적하는 방법에 비해 정확성이 높고 조명조건에 대해 안정된 특성이 있다. 본 논문에서는 이러한 성질을 이용하여 조명변화와 노이즈에 강인하게 카메라의 움직임을 추정하는 기법을 소개한다. 우선, 가버 필터뱅크를 사용하여 공간적으로 여과된 연속영상으로부터 계산된 위상의 크기를 기반으로 필터의 방향과 수직인 곳의 광류를 구한 후, 최소제곱법을 적용하여 어파인 모델에 상응하는 카메라의 움직임 파라미터를 구한다. 실험을 통하여 이러한 방법은 조명조건의 변화를 야기하는 디스플레이 기기를 피사체로 하여 카메라의 위치변화를 추정하는 방식의 영상기반 포인팅 디바이스에도 적용될 수 있음을 보인다.

• 센서학회지
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• 제19권2호
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• pp.99-111
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• 2010

This paper proposes an efficient hardware architecture to estimate disparities between 2D images for generating 3D depth images in a stereo vision system. Stereo matching methods are classified into global and local methods. The local matching method uses the cost functions based on pixel windows such as SAD(sum of absolute difference), SSD(sum of squared difference) and NCC(normalized cross correlation). The NCC-based cost function is less susceptible to differences in noise and lighting condition between left and right images than the subtraction-based functions such as SAD and SSD, and for this reason, the NCC is preferred to the other functions. However, software-based implementations are not adequate for the NCC-based real-time stereo matching, due to its numerous complex operations. Therefore, we propose a fast pipelined hardware architecture suitable for real-time operations of the NCC function. By adopting a block-based box-filtering scheme to perform NCC operations in parallel, the proposed architecture improves processing speed compared with the previous researches. In this architecture, it takes almost the same number of cycles to process all the pixels, irrespective of the window size. Also, the simulation results show that its disparity estimation has low error rate.

• 제어로봇시스템학회논문지
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• 제3권2호
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• pp.179-186
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• 1997

In this paper we suggest a development of surface defect inspection algorithms for cold mill strip. The defects which exist in a surface of cold mill strip have a scattering or singular distribution. This paper consists of preprocessing, feature extraction and defect classification. By preprocessing, the binarized defect image is achieved. In this procedure, Top-hit transform, adaptive thresholding, thinning and noise rejection are used. Especially, Top-hit transform using local min/max operation diminishes the effect of bad lighting. In feature extraction, geometric, moment and co-occurrence matrix features are calculated. For the defect classification, multilayer neural network is used. The proposed algorithm showed 15% error rate.

• 대기
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• 제29권4호
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• pp.463-480
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• 2019

This study classified heavy rain types from K-means clustering for the hourly relationship between rainfall intensity and cloud top height over the Korean peninsula, and then examined their statistical characteristics for the period of June~August 2013~2018. Total rainfall amount of warm-type events was 2.65 times larger than that of the cold-type, whereas the lightning frequency divided by total rainfall for the warm-type was only 46% of the cold-type. Typical cold-type cases exhibited high cloud top height around 16 km, large reflectivity in the upper layer, and frequent lightning flashes under convectively unstable condition. Phenomenally, the cold-type cases corresponded to cloud cluster or multi-cell thunderstorms. However, two warm-type cases related to Changma and typhoon were characterized by heavy rainfall due to long duration, relatively low cloud top height and upper-level reflectivity, and the absence of lightning under the convectively neutral and extremely humid conditions. This study further confirmed that the forecast skill of rainfall could be improved by applying correction factor with the overestimation for cold-type and underestimation for warm-type cases in the Local Data Assimilation and Prediction System (LDAPS) operational model (e.g., BIAS score was improved by 5%).

• 한국농촌건축학회논문집
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• 제11권3호
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• pp.11-18
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• 2009

The purpose of this paper is to find out the investigation of overseas case in Street Furnitures of Public Design. Thus this research regions select among the waterfront cities; Tokyo/Yokohama(Japan), Nies/Cannes(France), Shanghai(China), Vancouver(Canada), in addition to the city of art and romance; Paris. Above all, it is necessary to study concept of public design and definition of street furnitures. The survey data collected from forenamed cities and the items of street furnitures are various installments such as kiosk, bench, bollard, litter-bin, sign board, toilet, bus/taxi station, fence, shelter, lighting column, fountain, telephone-booth, clock-tower, automaton, bicycle stand, playing object etc. In this study street spaces are analysed that is related to regional surroundings and pedestrian's culture. Consequently, design trend of street furniture in foreign case analysis are going into thoroughly modern image as well as checking of form, color, material and maintenance system. According to the above findings, this paper will provide basic data for establishing of the street furniture and improving of public design to the regional citizen, local government officials and regional experts.

• 한국전기전자재료학회논문지
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• 제19권9호
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• pp.862-867
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• 2006

Bi-based nano-varistors and micro-varistors fabricated with each ZnO nano-powder and micro-powder were studied about characteristics on the surge capability in this study. ZnO nano-varistors were sintered in air at $1050^{\circ}C$ for 2 hr. The voltage-current and residual voltage properties of ZnO nano-varistor were compared with their of ZnO micrio-varistor. As a result of these properties, our ZnO nano-varistor has about 3 times at operating voltage as compared with conventional ZnO varistor fabricated with micro-powder and the residual voltage was 8.06 kV at nominal discharge current 101kA in the lighting impulse current test. And then the residual voltage rate 1.72 of our nano-varistor has had better performance than the 1.79 of micro-varistor because ZnO nano-varistor has shown much quick response property because of increasing effective cross-section area. Also, to analysis surge capability took thermal images for pyrexia temperature distribution with each of the varistors after operating varistors. Nano-varistor doesn't have shown local overheating and can confirm accurate temperature grade on the surface of its.

• 한국지능시스템학회논문지
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• 제20권5호
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• pp.688-693
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• 2010

주행 로봇 환경에서 비전 기반의 물체 인식은 물체의 주변 요소와 동적인 환경에 대한 다양한 영상처리 문제를 포함한다. SURF(Speeded Up Robust Features)는 영상의 크기와 회전변화에 강인하게 물체를 인식하는 알고리즘으로 많은 연구자에 의해 사용되고 있다. 하지만 SURF 기반의 영상처리 방법은 고차원의 벡터 성분을 사용하기 때문에 연산 과정에서 많은 시간을 소비하며, 그로 인해 실시간 시스템에서 수행의 어려움을 가지고 있다. 본 연구에서는 이러한 문제점을 해결하기 위해서, 연산량이 많은 SURF 처리 과정을 GPU(Graphics Processing Unit)에서 수행하도록 하여, 보다 빠른 영상 인식을 구현하고자 한다. NVIDIA의 CUDA 라이브러리를 이용하여 GPU 상의 수행 프로그램을 구현하고, 실험을 통해 이동 로봇의 속도와 영상의 크기변화에 따른 표식의 인식률 및 수행시간에 대해서 CPU와 성능을 비교한다.

• 한국실내디자인학회논문집
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• 제17권4호
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• pp.23-31
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• 2008

Rapid change of the era has caused change to consumption. New concept of consumer means not consumer who is simply provided a product, but a consumer who lays emphasis on value. That is to say, it indicates a consumer who values both on service and information as well as a product itself when they purchase. Therefore, the purpose of this research is to analyze the changes of POPs and objets at domestic and foreign fashion lingerie shops in different periods, and to encourage the effective introduction of POPs and objets for display at fashion lingerie shops in the future. I have used 100 pictures of 6 domestic brands and 80 of 6 foreign brands to analyze, and the periods were divided into 2000-2003, 2004-2007, and after 2008. The result of analyzing is as follows. First, give much information and great satisfaction to customers through the various types of POP, which convey the image and the concept of the products. If current POP was used only for sales, there ! should be various kinds and types of POPs to present not only basic information of products but also the value beyond it. Second, advance the products value by the presentation of diverse object. Furniture, fixtures, Lighting, Gift Box, Poster and mannequins should be used not to show simple props and presentation of product in the past, but to show brand images and Design concept of products.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제15권11호
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• pp.4043-4064
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• 2021

Night-time image quality evaluation is an urgent requirement in visual inspection. The lighting environment of night-time results in low brightness, low contrast, loss of detailed information, and colour dissonance of image, which remains a daunting task of delicately evaluating the image quality at night. A new blind quality assessment metric is presented for realistic night-time scenario through a comprehensive consideration of contrast, texture, and colour in this article. To be specific, image blocks' color-gray-difference (CGD) histogram that represents contrast features is computed at first. Next, texture features that are measured by the mean subtracted contrast normalized (MSCN)-weighted local binary pattern (LBP) histogram are calculated. Then statistical features in Lαβ colour space are detected. Finally, the quality prediction model is conducted by the support vector regression (SVR) based on extracted contrast, texture, and colour features. Experiments conducted on NNID, CCRIQ, LIVE-CH, and CID2013 databases indicate that the proposed metric is superior to the compared BIQA metrics.