• KSII Transactions on Internet and Information Systems (TIIS)
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• 제9권9호
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• pp.3412-3431
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• 2015

This paper considers the effect of co-channel interference on hybrid satellite-terrestrial relay network. In particular, we investigate the problem of amplify-and-forward (AF) relaying in hybrid satellite-terrestrial link, where the relay is interfered by multiple co-channel interferers. The direct link between satellite and terrestrial destination is not available due to masking by surroundings. The destination node can only receive signals from satellite with the assistance of a relay node situated at ground. The satellite-relay link is assumed to follow the shadowed Rice fading, while the channels of interferer-relay and relay-destination links experience Nakagami-m fading. For the considered AF relaying scheme, we first derive the analytical expression for the moment generating function (MGF) of the output signal-to-interference-plus-noise ratio (SINR). Then, we use the obtained MGF to derive the average symbol error rate (SER) of the considered scenario for M-ary phase shift keying (M-PSK) constellation under these generalized fading channels.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1993년도 춘계학술대회
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• pp.38-41
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• 1993

For efficient transmission and storage of digital images, the requirements of image compression is incresing. Because the medical images contain diagnostic information small distortion has been more important factor than the low rate in such images. Generally the distortion in image is the difference of pixel values. However the image is percieved by human visual systems. So it is reasonable that human visual system characteristics be used as criteria of the image compression. In this paper, the Just Noticeable Difference curve is used as criteria of determining the homogeniety of a block and acceptibility of distortions. And Block Truncation Coding using spatial masking effect of eyes is adopted to code the blocks which contain line components. And small blocks which varies slowly can be approximated to polynomial functions successfully. We proposed the hybrid block coding scheme based on the block characteristics and human visual system characteristics. Simulation to several kinds of the medical images using this method showed that medical images can be compressed 5:1 - 10:1 without noticeable distortion.

• 천문학회보
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• 제41권1호
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• pp.34.2-34.2
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• 2016

X-ray cavities are typically detected as surface brightness depression in X-ray diffuse emission from hot gas in high resolution X-ray images (i.e., Chandra and XMM-Newton). Showing the coincidence of location with radio jets, X-ray cavities imply that the radio jets interact with interstellar/intergalactic medium. It is important to understand them since they can be a clue of understanding AGN feedback to their host galaxies. To understand the physics of the AGN feedback, X-ray cavity has been actively studied while there are only a few statistical studies on X-ray cavity based on small or incomplete samples. Hence, a systematic study with a large sample is needed. With the condition of sufficient X-ray photons to detect surface brightness depression, we constructed a large sample of 133 galaxy clusters, galaxy groups, and individual galaxies to investigate X-ray cavities. We detected 201 cavities from 94 objects using two detection methods (i.e., beta-modeling and unsharp masking method), and confirmed the cavity size-distance relation over a large dynamical range. The size-distance relation does not vary for different environments (i.e., galaxy cluster, groups, and individual galaxies), suggesting that there is little environmental effect on the formation of X-ray cavity.

• 생물정신의학
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• 제3권1호
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• pp.30-36
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• 1996

Tardive dyskinesia is a syndrome of involuntary hyperkinetic abnormal movements that occurs during or shortly after the cessation of neuroleptic drug treatment. Typically, the movements are choreoatheoid. Other movements such as tics and dystonia may be present. Nonetheless, any dyskinesia seen in a neuroleptic-treated patient is not always neuroleptic-induced tardive dyskinesia. The prevalence of tardive dyskinesia varies widely, which reflects many methodological problems, such as differential diagnosis. symptom fluctuation, masking effect of neuroleptics, validated diagnostic criteria. Of suggested risk factors, only old age has been consistently found to be associated with an increased frequency of tardive dyskinesia. Many hypotheses about the pathophysiolgy of tardive kinesia are proposeed, but time-honored ones are not present. No consistently safe and effective treatments are found. Various treatment modalities signifies the general ineffectiveness of these agents for most patients. In general, reduction or cessation of neuroleptics, if possible, is recommended. Remission or improvemets of tardive dyskinesia after neuroleptics withdrawal usually occurs among most patients within three months.

• The Korean Journal of Physiology and Pharmacology
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• 제2권3호
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• pp.385-393
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• 1998

Human neutrophil elastase (HNElastase, EC 3.4.21.37), a causative factor of inflammatory diseases, was purified by Ultrogel AcA54 gel filtration and CM-Sephadex ion exchange chromatography. HNElastase was inhibited by phenylbutazone in a concentration dependent manner up to 0.4 mM, but as the concentration increased, the inhibitory effect gradually diminished. Binding of phenylbutazone to the human neutrophil elastase caused strong Raman shifts at 200, 440, and 1194 $cm^{-1}$. The peak at 1194 $cm^{-1}$ might be evidence of the presence $of\;-N=N-{\Phi}$ radical. The core area of the elastase, according to the visual molecular model of human neutrophil elastase, was structurally stable. A deeply situated active center was at the core area surrounded by hydrophobic amino acids. Directly neighboring the active site was one positively charged atom and two atoms carrying a negative charge, which enabled the enzyme and the drug to form a strong interaction. Phenylbutazone may form a binding, similar to a key & lock system to the atoms carrying opposite charges near the active site of the enzyme molecule. Furthermore, the hydrophobicity of the surrounding amino acid near the active site seemed to enhance the binding strength of phenylbutazone. Binding of phenylbutazone near the active site may cause masking of the active site, preventing the substrate from approaching the active site and inhibiting elastase activity.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권2호
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• pp.1080-1099
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• 2019

A better tradeoff between robustness and invisibility will be realized by using the just noticeable (JND) model into the quantization-based watermarking scheme. The JND model is usually used to describe the perception characteristics of human visual systems (HVS). According to the research of cognitive science, HVS can adaptively extract the structure features of an image. However, the existing JND models in the watermarking scheme do not consider the structure features. Therefore, a novel JND model is proposed, which includes three aspects: contrast sensitivity function, luminance adaptation, and contrast masking (CM). In this model, the CM effect is modeled by analyzing the direction features and texture complexity, which meets the human visual perception characteristics and matches well with the spread transform dither modulation (STDM) watermarking framework by employing a new method to measure edge intensity. Compared with the other existing JND models, the proposed JND model based on structural regularity is more efficient and applicable in the STDM watermarking scheme. In terms of the experimental results, the proposed scheme performs better than the other watermarking scheme based on the existing JND models.

• 한국수산과학회지
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• 제16권1호
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• pp.1-7
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• 1983

굴 통조림의 품질을 개선할 목적으로 자숙탈각한 원료 굴을 훈액처리하여 통조림함으로써 재래식 훈연기름담금통조림과 같은 향미를 내면서 녹변색조를 차폐할 수 있어 훈연색조가 고른 제품을 가공하는 방법을 검토하고, 아울러 제품 저장중의 품질안정성에 대하여 검토하였다. 1. 훈액처리굴기름담금통조립 제조조건은 자숙탈각한 굴을 $23.3\%$로 희석한 훈액(Smoke-EZ, Alpha Food Co.,Ltd.)에 30초간 침지한 다음 물기를 빼고, 106-2관 (각 3B관)에 충전하여, $116^{\circ}C$, 65 분간 살균한 후 냉각하는 것이었다. 2. 통조림 육의 색조변화를 보면, 대조제품(기름담금통조림)은 상온저장 20일 째부터 약간 녹변이 생기다가 저장 40일 이후에는 녹변이 확실하게 나타났다. 훈액 또는 훈연처리한 다음 기름담금한 통조림 제품은 녹변색조의 차폐효과가 있었는데, 훈액처리한 제품이 훈연처리한 제품보다 차폐효과가 더욱 좋고, 제품표면이 고른 훈연색조를 나타내었으며, 저장중 품질이 안정하게 유지되었다. 3. 제품의 경도와 toughness는 상온저장 3개월 째부터 약간 떨어졌으나, 탄성 및 응집성은 저장 4개월 째까지 거의 변화가 없었다.

• 분석과학
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• 제13권3호
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• pp.323-331
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• 2000

표면적과 다공성이 큰 Amberlite XAD-16 수지와 2-(2-thiazolylazo)-p-cresol(TAC) 및 4-(2-thiazolylazo)-orcinol(TAO)를 작용기로 하여 합성한 두가지 킬레이트수지인 XAD-16-TAC 및 XAD-16-TAO를 이용하여 Th(IV), U(VI) 및 Zr(IV)의 흡착특성을 뱃치법으로 조사하였다. 혼합 금속 이온 용액의 pH를 2-6으로 조절하고 24시간 진탕시킨 결과 최적 흡착 pH가 5-6범위이었으며, 가리움제로 NTA, CDTA 및 $NH_4F$를 택하여 혼합 금속 이온의 가리움효과를 조사한 결과 XAD-16-TAC 킬레이트 수지에서 혼합 금속 중 Zr(IV) 이온을, 그리고 XAD-16-TAO 수지로 Th(IV)이온을 분리하는데 $NH_4F$의 효과가 가장 우수한것으로 나타났다. 한편, $HNO_3$를 탈착제로 사용하여 농도를 0.1-2M로 변화시켜 금속이온의 탈착율을 조사한 결과 두가지 킬레이트 수지는 비슷한 경향을 나타내어 2 M에서는 Zr(IV)이온을 제외한 금속이온이 100% 탈착되었다. 그리고 Zr(IV), Th(IV) 및 U(VI)의 혼합금속용액에서 XAD-16-TAC 수지는 Zr(IV)을, XAD-16-TAO 수지는 Th(IV)을 선택적으로 분리할 수 있었다.

• 대한원격탐사학회지
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• 제34권2_2호
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• pp.327-338
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• 2018

본 연구는 운영레벨에서의Kompsat-5 SAR (Synthetic Aperture Radar) 영상과AIS (Automatic Identification System) 자료를 이용한 선박탐지 모니터링 가능성을 검토하였다. 분석을 위해 신진항 서측연안과 제주항 북측연안에서 수집된 Kompsat-5 SLC 영상과 연안에서 수집된 AIS 자료를 사용하였다. Kompsat-5 영상의 선박탐지를 위해 HVAS (Human Visual Attention System) 알고리즘을 적용하였다. HVAS는 CFAR (Constant False Alarm Rate)에 비해 탐지속도와 탐지율 측면에서 뛰어나다는 장점을 가지고 있다. 통합 분석결과 소형선박을 제외하고 Kompsat-5 선박탐지 결과와 AIS는 전반적으로 일치하는 것으로 분석되었다. Kompsat-5 영상에서 탐지되었으나 AIS 자료에서 탐지되지 않은 선박은 육안 판독을 통해 AIS 자료의 부재로 인한 것으로 보인다. 한편 SAR 영상에서도 선박의 기포항적, 육지 masking을 위해 사용된 DEM 파일의 오차(또는 위성궤도 오차), 그리고 고스트 현상에 의한 오탐지가 발생하였다. 향후 SAR 영상 분석 알고리즘 개선과 신뢰성 있는 AIS 자료 확보를 통한 운영레벨에서의 선박탐지 모니터링 기술 개발은 국가해양영토 광역감시망 구축에 크기 기여할 것이다.

• 한국식품과학회지
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• 제42권1호
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• pp.63-68
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• 2010

본 연구에서는 천연소취식물인 감잎, 솔잎, 회향을 세절 및 추출하여 김치에 첨가하여 냄새를 masking하는 농도의 조건을 설정하고, 천연물 첨가에 따라 김치의 숙성에 미치는 연향과 휘발성 향기 성분을 분석하였다. 감잎, 솔잎, 회향을 세절물과 추출물로 김치에 첨가하여 숙성 후 신내와 군덕내에 대해 관능평가한 결과, 김치에 천연소취식물을 첨가할 때 세절물보다 추출물을 첨가했을 경우에 김치냄새의 masking 효과가 높았으며, 솔잎추출물 0.3-0.6%를 첨가한 김치와 회향추출물 0.05-0.1%를 첨가한 김치가 관능적으로 효과가 높았다. 또한 솔잎추출물 및 회향추출물을 첨가한 김치는 일반김치와 비교했을 때 pH, 총산도 및 유산균수 등의 발효특성인자들에 유의적으로 영향을 미쳤다. 또한 GC/MS로 김치 및 소취식물 추출물의 향기 성분을 분석하여, 천연소취 식물을 첨가한 김치와 솔잎 및 회향추출물의 향기 성분과의 연관성을 검토하였다. 결과적으로 솔잎 및 회향추출물은 김치의 발효특성에 영향을 주어 김치 특유의 냄새를 저감시킬 수 있는 것으로 확인되었다.