• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2010년도 제34회 춘계학술대회논문집
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• pp.190-193
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• 2010

고성능 액체로켓의 핵심 요소인 고압 연소기에 사용되는 분사기에 대한 혼합 및 연소 특성을 도출하기 위하여 초임계 상태에 적용되는 혼합 및 연소모델을 수치적으로 연구하였다. 난류모델은 LES(Large Eddy Simulation)를 기반으로 하였고, 난류연소모델은 혼합분율(Z)을 이용한 Laminar Flamelet Model을 사용하였다. 그리고 초임계 영역의 상태량을 계산하기위해 Soave Redlich-Kwong 상태 방정식, 점성계수와 열전도도에 대하여 Chung이 제안한 고압상태 혼합물에 대한 방정식, 확산계수에 대하여 Fuller 이론에 Takahashi가 제안한 고압상태의 특징을 고려한 식을 적용하였다. 계산결과는 선행연구자의 결과와 비교하였고, LOx post 후방에 발생되는 와류에 따른 보염영역에 대하여 연구하였다.

• 한국염색가공학회:학술대회논문집
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• 한국염색가공학회 2010년도 제3회 국제학회
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• pp.49-50
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• 2010

The near-infrared absorbing donor-acceptor chromophores have been investigated by varying the electron donating and accepting molecular moiety. A series of near-infrared absorbing chromophores were offered narrow and intense absorption band in a various organic solvents. The dyes synthesised were, however, strongly bathochromic shift which extended well into the near-infrared region. The functional uses of dyes are vast in number, and it is convenient to classify them in some way. In all cases, it is the $\Pi$-chromophore that plays a major role in the functional application. "Light absorption" is of course the most commonly used property of a dye chromophore, and it can be employed directly, e.g. in light filters and optical data recording, or it can be used to drive further functional processes, e.g. fluorescence, photochromism, photosensitization.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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• pp.428-428
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• 2002

The scientific objectives of PACRIM (Pacific Rim) are to advance the understanding of polarimetric and interferometric radar and to promote its application in environmental research designed to detect and quantify changes found in both the physical and humanly dominated ecosystems on the earth's surface. The information derived is used to more readily identify environments at risk; improve environmental decision making and the management of resources and thereby lead to the implementation of more effective and sustainable land use practices. PACRIM is a collaborative research project was organized by NASA's Mission to Planet Earth, Airborne Sciences Program; the Jet Propulsion Laboratory; CSIRO-COSSA and the Centre for Remote Sensing and GIS at the University of New South Wales. A decade of working with AIRSAR data (1993-2003) in the Australia-Asian-Pacific region has provided the opportunity for more than 400 investigators from 20 countries to collect, analyse, interpret and apply state-of-the-art radar data to earth-science studies. This has been achieved by scientists working within seven broad research themes; o Forestry and vegetation o Geology and tectonic processes o Interferometry o Disaster management o Coastal analysis o Agriculture o Urban and regional development. This paper presents an overview of the three data acquisition missions (1993,1996 and 2000) and the science research outcomes achieved from analyzing high quality radar data.

• 한국정보통신학회논문지
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• 제11권12호
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• pp.2382-2390
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• 2007

본 논문에서는 비선형 앰프를 선형화 하는 다항식에 기반한 사전왜곡 알고리즘을 제안한다. 제안된 방식은 기존의 다항식 기반 방식과는 다르게 사후왜곡기의 도움 없이 직접 학습 방식으로 사전왜곡 계수를 추정한다. 먼저 앰프의 특성이 부분 선형으로 가정하여 알고리즘이 유도되고, 다음에 이 알고리즘을 앰프에 대한 어떠한 가정이 필요없는 구조로 변경한다. 제안된 사전왜곡기는 복소 계수를 가지는 다항식으로 구성되며 다항식의 계수는 RLS(recursive least squares)에 기반하여 찾게 된다. 컴퓨터 모의실험에 의하면 제안된 직접방식의 알고리즘이 기존의 간접 학습 방식에 비해 앰프의 초기 계수나 포화 영역에서 강인한 특성을 보인다.

• BMB Reports
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• 제54권8호
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• pp.413-418
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• 2021

ErbB3-binding protein 1 (EBP1) is a multifunctional protein associated with neural development. Loss of Ebp1 leads to upregulation of the gene silencing unit suppressor of variegation 3-9 homolog 1 (Suv39H1)/DNA (cytosine 5)-methyltransferase (DNMT1). EBP1 directly binds to the promoter region of DNMT1, repressing DNA methylation, and hence, promoting neural development. In the current study, we showed that EBP1 suppresses histone methyltransferase activity of Suv39H1 by promoting ubiquitin-proteasome system (UPS)-dependent degradation of Suv39H1. In addition, we showed that EBP1 directly interacts with Suv39H1, and this interaction is required for recruiting the E3 ligase MDM2 for Suv39H1 degradation. Thus, our findings suggest that EBP1 regulates UPS-dependent degradation of Suv39H1 to govern proper heterochromatin assembly during neural development.

• The Korean Journal of Physiology and Pharmacology
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• 제26권1호
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• pp.59-65
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• 2022

Phosphorylation levels of glycogen synthase kinase 3β (GSK3β) negatively correlated with psychomotor stimulant-induced locomotor activity. Locomotor sensitization induced by psychomotor stimulants was previously shown to selectively accompany the decrease of GSK3β phosphorylation in the nucleus accumbens (NAcc) core, suggesting that intact GSK3β activity in this region is necessary for psychomotor stimulants to produce locomotor sensitization. Similarly, GSK3β in the NAcc was also implicated in mediating the conditioned effects formed by the associations of psychomotor stimulants. However, it remains undetermined whether GSK3β plays a differential role in the two sub-regions (core and shell) of the NAcc in the expression of drug-conditioned behaviors. In the present study, we found that GSK3β phosphorylation was significantly lower in the NAcc shell obtained from rats expressing amphetamine (AMPH)-induced conditioned locomotor activity. Further, we demonstrated that these effects were normalized by treatment with lithium chloride, a GSK3β inhibitor. These results suggest that the behavior produced by AMPH itself and a conditioned behavior formed by associations with AMPH are differentially mediated by the two sub-regions of the NAcc.

• 대한정형외과학회지
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• 제56권4호
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• pp.341-345
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• 2021

슬개골하 지방괴는 슬관절 전방 부위에 위치한 세 가지의 지방괴 중 하나로 슬개골하 지방괴의 손상이 비교적 흔하며, 원인은 주로 수술에 인한 의인성 손상 및 충돌 등에 의한 반복적인 미세 외상 등으로 알려져 있다. 저자들은 국내 및 국외에 보고된 적이 없는 슬관절의 과굴곡 상태로 전면부에 좌상을 입은 후 발생한 슬개골하 지방괴의 급성 분리 손상을 자기공명영상을 통해 확인하였고, 이를 보존적으로 치료하여 완치된 1예를 경험하였기에 보고하는 바이다.

• 한국진공학회지
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• 제20권4호
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• pp.266-270
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• 2011

본 연구에서는 W (Tungsten)를 주 구성 물질로 불순물 C (Carbon)과 N (Nitrogen)을 첨가한 W-C-N 확산방지막 시편을 제조하였고, $N_2$가스의 유량을 변화시키면서 확산방지막을 제조하여 각각의 시료에 대하여 $600^{\circ}C$열처리를 하였다. 실험 결과 질소유량의 변화에 따라 시편의 탄소성 구간층의 물성 변화율이 시편의 탄성구간보다 큰 것을 알아냈다. 이는 질소 가스의 유량 변화가 시편의 탄소성 구간에 더욱 직접적으로 연관이 되었다는 것을 알 수 있었다. 각 시료는 16회 연속 압입 실험을 실시하여 Stress-strain curve를 통하여 질소 가스의 유량이 2 sccm인 박막의 분산이 적음을 알아냈고, 연속압입을 통하여 얻어진 상항복점의 표준 편차 역시 질소 가스의 유량이 2 sccm인 박막이 가장 적다는 것을 알 수 있었다. Stress-strain curve 분산과 상항복점의 Stress 값의 표준 편차의 크기로 부터 박막의 안정도를 예상할 수 있었으며, 이 결과로부터 W-C-N 박막은 질소 유량에 따라 박막의 안정도가 변화하는 것을 알았다.

• 한국수자원학회논문집
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• 제46권6호
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• pp.613-627
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• 2013

본 연구에서는 지속기간별(1-, 3-, 6-, 12-, 24개월)로 가장 가뭄이 심한 해의 5월 건조현상을 지역별로 분석하기 위해 1973년부터 2006년까지 우리나라 53개 기후관측지점에서 관측된 월별 기후자료를 이용하여 FAO Penman-Monteith 기준잠재증발산량(RET)을 산정하였다. 그리고 강수량(P)에 대한 RET의 비(P/RET)를 이용하여 건조지수(aridity index)와 P/RET의 변동지수(variation index, VI)를 산정하고, 표준강수지수(standard precipitation index, SPI)와 비교하였다. 우리나라 지역별 건조현상을 파악하기 위해 53개 기후관측지점을 20개 연구지역으로 구분하여 분석하였다. 또한 지역별 건조지수의 추세분석을 위해 Mann-Kendall 추세분석, Spearman rank test 그리고 Sen's slope을 적용하였다. 분석 결과에 의하면 각 지속기간별로 P/RET의 변동지수(VI)와 표준강수지수사이에 양호한 상관관계를 보였다. 또한 우리나라 전역에 걸쳐서 지속기간이 단기화 될수록 5월 기후가 더욱 건조한 것으로 나타났다. 3개월이나 6개월 지속기간의 경우 대부분 지역에서 유의하거나 혹은 유의하지 않은 수준에서 건조지수의 감소추세를 보였다. 반면에 12개월 및 24개월 지속기간의 경우 유의한 건조지수의 감소추세를 보이는 지역은 없는 것으로 나타났다.

• 대한치과교정학회지
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• 제24권2호
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• pp.275-294
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• 1994

The occlusal interference during adolescent period makes some effects on growth and development and morphological changes. And so, if we could predict the the timing and results of orthodontic treatment who have occlusal interference during adolescent period, it may be helpful for diagnosis and treatment planning of orthodontic treatment. For about those, the purpose of this study was to evaluate the effects of the posterolateral displacement by the metal casting crown with inclined pathway on the mandibular condyle and morphologic changes of mandible in the rat. The experimental animals were thirty six Sprague-Dawley male rats of 8 weeks old. Eight of them was used as control group, and experimental group 1 ( continuous appliance wearing group ) was composed of sixteen and experimental group 2 ( appliance removal group after worn the appliances during 3 months ) was composed of remaining twelve. The animals of experimental grouop 1 were sacrificed after 1, 2, 3, 6 months from beginning of the experiment and experimental group 2 were sacrificed 1, 2, 3 months after removal of the appliance from worn the appliance during 3 months. Both of mandible and temporomandibular joint were observed histologically and radiologically. The results were as follows : 1. In experimental group 1, the mandibular length and lower posterior height were decreased with experimental period, while the lower anterior height was increased, and the curvature of lower incisors and lingual inclination of anterior alveolar bone were profound as compared with control group. 2. In experimental group 1, both of the thickness of the condylar cartilage were thinned in the posterosuperior region, and this phenomenon was more prominent on right than left in 3-Mo experimental period and both sides were marked thinned in 6-Mo experimental period. 3. In experimental group 2, the lower anterior height was low and lower posterior height was high as compared with experimental group 1, and the curvature of lower incisors and lingual inclination of anterior alveolar bone were recovered to control group. 4. In experimental group 2, both of the thickness of the condylar cartilage were thickened in the posterosuperior region, and this phenomenon was more prominent with experimental period. 5. In experimental group 2, the mandibular length was short, lower anterior height was hight, the curvature of lower incisors were profound, and in histologically, both of the thickness of the condylar cartilage were thickened in the posterosuperior region as compared with control group. As shown above, the occlusal interfemce affected the condylar cartilage, curvature of lower incisor, inclination of anterior alveolar bone, mandibular length, and anterior and posterior height. When the interference was removed, significant recover was found in condylar cartilage, mandibular length, and posterior height. Although no significance was found, other items of measurement showed trends for recovery.