• 한국물환경학회지
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• 제34권2호
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• pp.149-156
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• 2018

Oxidation of Ciprofloxacin, Trimethoprim, and Enrofloxacin by ozone was experimentally investigated to observe the effects of background water quality (such as ultrapure water, humic acid, and biologically treated wastewater) and water temperature on the removal rate of these antibiotics, and, thereby, to be able to provide design information when the ozone treatment process is adopted. Initial concentrations of the antibiotics spiked to $10{\mu}g/L$, and the ozone dose was 1, 2, 3, 5, and 8 mg/L. While the removal rate of Ciprofloxacin under ultrapure water background by ozone oxidation was over 99%, the removal rate under humic acid and biologically treated wastewater background was markedly lower, in the range of 49.3% ~ 99% and 19.8 % ~ 99 %, respectively. When water temperature is decreased from $20^{\circ}C$ to $4^{\circ}C$, the removal rate is reduced from the range of 19.8% ~ 99 % to the range of 7.5 % ~ 99 % under a biologically treated wastewater background. The effects of background and temperature on the removal rate of Trimethoprim and Enrofloxacin were similar to that of Ciprofloxacin, but the degree was different. Therefore, it is concluded that the background of water to be treated, as well as water temperature, should be taken into consideration when the design factor, such as ozone dose, is determined, so that the treatment objective of the ozone treatment process can be most effectively met.

• 전자공학회논문지
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• 제50권9호
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• pp.164-171
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• 2013

X-선 스펙트럼 데이터는 물질의 성분과 관련이 없는 많은 양의 백그라운드 신호를 포함하고 있다. XRF는 스펙트럼에서 가우시안 형태의 피크 정보의 위치와 크기를 이용하여 시료의 성분과 함유량을 분석하며, 시료의 성분과 함유량을 정확히 분석하기 위해서는 백그라운드를 정확하게 제거하여야 한다. 백그라운드를 제거하기 위한 방법으로는 모폴로지, SNIP, 임계값 방법들이 적용되고 있으며, 구간별 임계값 방법에 대한 연구가 활발히 진행되었다. 본 논문에서 제안하는 백그라운드 제거 방법은 구간별 임계값 방법을 개선한 방법으로 구간분할과 영역분류, 백그라운드추정으로 구성된다. 제안된 방법이 백그라운드 제거에서 기존의 모폴로지 기반 방법이나 SNIP 방법에 비해 좋은 성능을 보임을 실험을 통해 검증하였다.

• 상하수도학회지
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• 제31권4호
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• pp.347-356
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• 2017

Oxidation of erythromycin, sulfamethazine and sulfathiazole by ozone was experimentally investigated to see the effects of background water quality such as ultrapure water, humic acid and biologically treated wastewater and water temperature on the removal rate, consequently to provide design information when the ozone treatment process is adopted. Initial concentration of the antibiotics was spiked to $10{\mu}g/l$ and ozone dose was 1, 2, 3, 5, 8 mg/l. While the removal rate of erythromycin under ultrapure water background by ozone oxidation was over 99%, that under humic acid and biologically treated wastewater background was markedly reduced to the range of 59.8%~99% and 17.0%~99%, respectively. When water temperature is decreased from $20^{\circ}C$ to $4^{\circ}C$, the removal rate is reduced from the range of 17.0%~99% to the range of 9.4%~97.4% under biologically treated wastewater background. The effects of background and temperature on the removal rate of sulfamethazine and sulfathiazole were similar to erythromycin, but the degree was different. Therefore, it is concluded that the background of water to be treated as well as water temperature should be taken into consideration when the design factor such as ozone dose is determined to meet the treatment objective in the ozone treatment process.

• Journal of Electrical Engineering and Technology
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• 제9권6호
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• pp.2126-2133
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• 2014

We present a scalable object tracking framework, which is capable of removing shadows and tracking the people. The framework consists of background subtraction, fuzzy based shadow removal and boundary tracking algorithm. This work proposes a general-purpose method that combines statistical assumptions with the object-level knowledge of moving objects, apparent objects, and shadows acquired in the processing of the previous frames. Pixels belonging to moving objects and shadows are processed differently in order to supply an object-based selective update. Experimental results demonstrate that the proposed method is able to track the object boundaries under significant shadows with noise and background clutter.

• 한국군사과학기술학회지
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• 제17권1호
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• pp.115-121
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• 2014

In this paper, we propose a robust background removal integral projection(BRIP) method which can detect close surface targets in coastal environment for IRST. Row pixels of background region from coastal infrared image show similar response. Thus, the proposed BRIP is calculated after horizontal and vertical background estimations and removals are performed sequentially. Finally, surface large targets can be detected using the results of the BRIP. Experimental results on a set of real infrared image sequence show that the proposed method could fully detect ships in every frame.

• 한국멀티미디어학회논문지
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• 제17권4호
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• pp.420-432
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• 2014

In detection of moving objects from video sequences, an essential process for intelligent visual surveillance, the cast shadows accompanying moving objects are different from background so that they may be easily extracted as foreground object blobs, which causes errors in localization, segmentation, tracking and classification of objects. Most of the previous research results about moving cast shadow detection and removal usually utilize color information about objects and scenes. In this paper, we proposes a novel cast shadow removal method of moving objects in gray level video data for visual surveillance application. The proposed method utilizes observations about edge patterns in the shadow region in the current frame and the corresponding region in the background scene, and applies Laplacian edge detector to the blob regions in the current frame and the corresponding regions in the background scene. Then, the product of the outcomes of application determines moving object blob pixels from the blob pixels in the foreground mask. The minimal rectangle regions containing all blob pixles classified as moving object pixels are extracted. The proposed method is simple but turns out practically very effective for Adative Gaussian Mixture Model-based object detection of intelligent visual surveillance applications, which is verified through experiments.

• International Journal of Knowledge Content Development & Technology
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• 제5권2호
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• pp.11-24
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• 2015

It is common for archive libraries to provide public access to historical and ancient document image collections. It is common for such document images to require specialized processing in order to remove background noise and become more legible. Document images may be contaminated with noise during transmission, scanning or conversion to digital form. We can categorize noises by identifying their features and can search for similar patterns in a document image to choose appropriate methods for their removal. In this paper, we propose a hybrid binarization approach for improving the quality of old documents using a combination of global and local thresholding. This article also reviews noises that might appear in scanned document images and discusses some noise removal methods.

• 전자공학회논문지
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• 제54권8호
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• pp.67-80
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• 2017

본 논문에서는 추정된 시공간 배경 정보를 이용하여 자유 시점에서 합성영상을 생성하기 위한 홀채움 방식을 제안한다. 시간적 배경 정보를 추정하기 위해 비겹침 패치 기반의 배경 코드북을 이용한 새로운 시간적 배경 모델을 소개한다. 더불어, 공간적 배경 후보의 하한 및 상한 값의 제약 조건을 설정하는 깊이영상 기반 공간적 국부 배경 예측 방식에 대해 제안한다. 추정된 시간적 배경 정보와 공간적 배경 정보의 유사도를 비교하여 가려짐 배경 영역의 홀채움 과정을 수행한다. 또한 3-D 워핑 후 발생하는 컬러영상과 깊이영상간의 불일치 문제를 해결하기 위해 깊이영상 기반의 고스트 제거 필터를 기술한다. 마지막으로 잔여 홀을 채우기 위해 새로운 깊이 항을 포함한 우선순위 함수를 이용하여 인페인팅 방식이 적용된다. 실험 결과를 통해 기존의 홀채움 방식들과 비교하여 제안하는 방식의 객관적, 주관적 성능의 우수성을 확인할 수 있었다.

• 전자공학회논문지S
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• 제34S권10호
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• pp.104-111
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• 1997

It is known as a difficult problem to recognize text-background mixed documents. In this paper a new string extraction algorithm, using mathematical morphology for the document consisting of text and overlapped periodic background pattern, is proposed. The algorithm consists of pattern periodicity feature extraction and background removal. The extracted pattern periodicity feature is used to determine the shape of structuring elements for morphological pre- and post-processing to remove background. The effectiveness of the proposed algorithm over the existing one is also verified through the experiments with various test documents.

• 한국전자통신학회논문지
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• 제4권3호
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• pp.204-210
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• 2009

영상 감시 분야 중 침입자를 자동으로 인식해 내는 기술의 전처리 과정인 배경 분리 방법과 이동하는 객체의 주변에 있는 그림자를 제거하는 방법에 대한 많은 연구가 있어 왔다. 이동하는 객체와 그림자의 분리가 정확하지 않을 경우 이동 객체의 정확한 형태 분석이 어려우며, 위치 추적 또한 어렵다. 본 논문에서는 그림자를 제거하는 방법으로 명도 값을 활용하는 방법을 제안한다. 그림자 영역이 배경 영역과 비교하여 색상의 변화는 발생하지 않고, 명도 차이만 발생한다는 점에 착안한 방법으로, 이전 프레임에서 그림자 제거에 사용했던 임계값을 다음 프레임에서 갱신하여 사용하는 방법이다.