• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.11
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• pp.4656-4663
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• 2010

In this study, the 3D computational fluid dynamics (CFD) was performed in relation to the internal fluid characteristics, flow distribution, air mean ages, and residence time for the development of the most optimal model in the complex post-disposal device. As it is expected that a channeling (drift) would be made by the semi-dry reactor due to the large difference in the flow distribution by the compartment in the bag filter, a structural improvement should be urgently made for more uniformed flow distribution in the bag filter. In addition, it showed the possibility that the velocity field and distribution characteristics of the residence time could be improved through a modification to inlet structure of the spray dryer reactor. The complex post-disposal device, modified and supplemented with this analysis, integrated the semi-dry reactor and the bag filter in a single body, so it follows that the improvement can make the device compact, the installation area, the operation fee, and management more convenient.

• Proceedings of the Korea Information Processing Society Conference
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• 2007.05a
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• pp.463-466
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• 2007

현재 웹 서비스에서 주로 사용하고 있는 키워드 기반 검색은 사용자의 의도와는 상관없는 정보까지 검색하는 경우가 많아서, 실제로 원하는 정보를 찾는데 많은 시간과 노력을 요구한다는 단점이 있다. 이러한 단점을 보완하기 위해서 최근 시맨틱 웹이라는 개념이 등장하였으며, 본 논문에서는 검색 결과의 신뢰성을 향상시키기 위해 온톨로지를 기반으로 시맨틱 검색시스템을 설계하였다. 본 논문에서 설계한 온톨로지 기반의 시맨틱 검색 시스템은 기능적으로 크게 두 부분으로 구성되어 있다. 즉, 자료 수집을 하는 로봇 에이전트와 온톨로지를 기반으로 자료를 검색하는 시맨틱 검색 엔진으로 구성된다. 로봇 에이전트는 자율적으로 웹을 순회하면서 자료를 수집하고 필터링하여 메타데이터 저장소로 가져오는 역할을 한다. 시맨틱 검색 엔진은 사용자의 검색 폼으로부터 전달된 정보 검색 요구사항을 기초로 시맨틱 질의어로 변환한 후, 온톨로지 저장소를 활용하여 검색한다. 시맨틱 검색 엔진은 사용자가 입력한 검색어를 시맨틱 질의어로 변환해 주는 질의처리 모듈과 사용자의 의도를 추론하여 보다 향상된 검색을 가능하게 해주는 추론(Inference) 모듈, 온톨로지를 보관해주는 온톨로지 저장소 등으로 구성된다. 본 논문에서 설계한 온톨로지 기반의 시맨틱 검색 시스템은 키워드 기반 검색에 비해 사용자가 원하는 정보를 찾는데 소요되는 시간과 노력을 줄여 주고, 사용자의 의도에 적합한 정보를 제공할 것으로 기대된다.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.42 no.10
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• pp.833-841
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• 2014

This paper proposes an algorithm to estimate the wind velocity by tracking free flying balloons. Balloons used in this method are expendable but inexpensive, which increases the usefulness of the method. Also we can obtain accurate 3D information by using multiple cameras and estimate the wind velocity of the local field. The proposed system consists of aerodynamic modeling of the balloon, a tracking algorithm using image processing, and the velocity estimation algorithm. We performed unit tests of each algorithm for the verification. The method is validated using a system simulation and sources of error case identified.

• Journal of the Korea Society of Computer and Information
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• v.8 no.4
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• pp.63-68
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• 2003

Almost the system are usually taken by means of shapes and positions of ridge's end-points and bifurcation in the fingerprint recognition. but we studied about recognition of polluted fingerprint by chain code ridges. the results and sequence of processing are summarized as follows. (1)Capture several kinds of polluted fingerprint image. (2)Preprocessing(median filtering for removing noises, local and global histogram equalization, dilation and erosion, thinning and remove pseudo image), (3)Rebuild ridge line after Least Square Processing, (4)Compute distribution of chain code vector, (5)The results are almost same values of each vector of preprocessed fingerprint images. From the results, we can surmised more successful fingerprints recognition system in combination with other system by singular points

• Journal of the Institute of Convergence Signal Processing
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• v.5 no.2
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• pp.119-125
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• 2004

The direction component uses mainly the sobel and FFT method. The sobel method is difficult to set representative direction when we wish to extract representative direction when we wish to extract representative direction component and the complicated processing process of sobel mask because same value appears in the low provision image or high provision image and we cannot accumulate tilt size in case of making accumulate after making unit vector to pixel. The method that uses FFT conversion for direction extraction is possible in case that ridge has correct direction specification and must use a special direction filter. After thinning the binary image to supplement above weak point in the paper, we extract direction component by pixel unit, and we extract the most direction components of pixel that exist in block of 8${\times}$8 pixels size as representative direction of ridge.

• Journal of the Korea Organic Resources Recycling Association
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• v.22 no.3
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• pp.23-32
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• 2014

Recently, it is increase in the processing of organic waste using anaerobic digestion. Therefore, the studies on the processing method for increasing the anaerobic digestion waste water. But it is very difficult to solid-liquid separation, because the characteristics of anaerobic digestion waste water. So this study evaluate solid-liquid separation efficiency of anaerobic digestion sludge using CST(Capillary Suction Time), TTF(Time to Filter). To address this problem, a membrane filter press of the lab scale was produced and the anaerobic digestion wastewater was applied to it. Polymer coagulants were found to be most suitable 7192PLUS and 1T60, It is necessary to minimum injection concentration is 7192PLUS (200 mg/L), 1T60 (100 mg/L). To evaluate dehydration efficiency, it was measured the moisture content of the dehydrated cake and suspended solids of decanted water. As a result, showed that a high removal efficiency of 97.4% when the solid-liquid separation using the membrane filter press. And the moisture content of the dehydrated cake was less than 65%.

• Journal of Broadcast Engineering
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• v.20 no.1
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• pp.153-163
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• 2015

This paper proposes a rain detection and removal algorithm that is robust against camera motion in video sequences. In detection part, the proposed algorithm initially detects possible rain streaks by using intensity properties and spatial properties. Then, the rain streak candidates are selected based on Gaussian distribution model. In removal part, a non-rain block matching algorithm is performed between adjacent frames to find similar blocks to the block that has rain pixels. If the similar blocks to the block are obtained, the rain region of the block is reconstructed by non-local means (NLM) filter using the similar neighbors. Experimental results show that the proposed algorithm outperforms the previous works in terms of subjective visual quality of de-rained video sequences.

• Korean Journal of Optics and Photonics
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• v.10 no.1
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• pp.21-26
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• 1999

The technique for calibrating standard particles larger than 1 $\mu$m by using an optical array sizing method has been established. The system consists of an optical microscope with transmission light source, a CCD camera, and a computer equipped with a frame grabber. The center distance between two spheres located at both ends of a row which consists of N spheres is measured in terms of pixel numbers, and divided by (N-1) to obtain the average pixel numbers per particle. This value is multiplied by length conversion constant, which has been determined in advance, to obtain the mean diameter of polystylene spheres. The length conversion constant is found from the microscopic image of calibrated standard stage micrometer plate. In order to reduce error in finding center positions of the scale and particles in the image, a software filter which dilates bright (or dark) object has been used. Spheres having nominal size of 1, 2, 3, 5, and 10$\mu$m were measured, and the maximum deviation of the measured mean diameter valus from their certified values was 0.7%. Standard particles which is larger than 1 $\mu$m can be calibrated by this method with measuredment uncertainy (k=2) lees than 1.53%.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2012.03a
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• pp.92-92
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• 2012

나노필라멘트 섬유는 직편물 등으로 구조/용도 다양화 가능하다. 나노필라멘트 섬유는 소재특유의 닦음성, 흡착성, 고밀도 특성 등을 활용하여 직편물의 형태로 다양한 용도 개발이 가능하며, 나노기술을 접목시킨 새로운 기능성과 고성능 섬유 소재 개발을 통한 자동차 분야의 개발 트랜드인 고급화, 경량화, 고성능화 추진을 위해 연료전지, 신슐레이터, 고성능 필터, 시트나 도어트림, 헤드라인과 같은 인테리어류와 전자 분야의 제조원가 절감, 공정 단순화를 위해 프린터 토너, 하드디스크 연마제, 다용도 No Dust Cleaner 등의 개발, 의료/바이오 분야의 혈액필터, 수술용 보호제, 창상억제제(유착 방지막), 항균마스크, 의료용 약물전달 시스템 및 환경 분야의 정수/공기 정화 시스템, 건축 토목용 보강제, 고(高)인성 콘크리트, 폐수처리용 슬러리 담체(Matrix) 등 다양한 분야로 용도 개발이 가능하다. 본 연구는 나노필라멘트의 다양한 분야로의 용도 개발 적용의 기초연구로서, 부직포 상으로 얻어지는 나노섬유 제조기술의 단점인 직경의 불균일, 물리적 특성의 한계와 필라멘트가 아닌 단섬유로 인해 발생하는 용도 및 상품 개발에의 제한성을 개선하기 위하여 연속적으로 필라멘트를 생산가능한 해도형 복합방사 방법을 도입하여 개발한 장섬유 필라멘트 형태의 해도형 나노 섬유 소재를 활용하는 것으로 방사된 SDY 형태의 나노필라멘트 섬유를 제직상에서의 작업성 용이 및 직물의 벌키성 증대와 Crimp성을 향상 시켜 터치감 및 후가공에 용이할 수 있도록 DTY를 제조함에 있어 기존 일반 POY사에서의 DTY공정과는 달리 소재의 특성 즉, 해도사의 해성분 및 도성분의 후공정을 감안하여 최적의 Crimp는 발현하되 단면의 형상을 유지할 수 있는 다양한 사가공 조건을 설정 하고 이에 따라 가공사를 생산하여 공정조건에 따른 가공사의 물성 및 수축특성을 비교 분석 하여 염색 및 후가공시 소재의 물성 및 수축특성이 미치는 영향성을 살펴보고자 하였다.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.34 no.5
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• pp.499-504
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• 2010

It is important to determine the exact soot mass in a DPF system in order to control the timing of PM regeneration. The soot mass accumulated in a filter can be estimated from the pressure drop in the filter and the exhaust gas flow rates. In this study, the soot index is defined as the pressure drop in the DPF divided by the pressure drop in a DOC. An effective signal processing method for determining the soot index is proposed; the results yielded by this method indicate good correlation between the soot index and the amount of soot loaded into the filter for both steady-state and transient-state operating conditions in a 3L diesel engine for passenger vehicles.