• 한국해양학회지:바다
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• 제19권4호
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• pp.256-264
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• 2014

가로림만 저서다모류군집의 특성을 파악하기 위하여 2006년 4월부터 2007년 4월까지 5회에 걸쳐 현장조사를 실시하였다. 가로림만은 반폐쇄성 매만으로 2분지형의 수로를 통해 해수의 유출입이 일어나며 수로 주변으로 넓은 갯벌이 형성되어 있다. 저서다모류는 전체 대형저서동물군집중 개체수에 있어서 65.1%를 차지하는 우점 동물군이었다. 출현종수는 내만역이 만입구나 외해역에 비해, 그리고 갯벌 지역이 수로 지역에 비해 많은 편이었다. 서식밀도 역시 수로 지역보다 갯벌 지역에서 높았다. 주요 우점다모류는 기회주의종으로 잘 알려진 Prionospio sp., Heteromastus filiformis, Lumbrineris longifolia 등이었다. Prionospio sp.와 H. filiformis는 주로 내만역의 갯벌에 주로 서식하였고, 반면 L. longifolia는 수로지역과 만 입구역에 서식하였다. 집괴분석과 nMDS 분석 결과 정점군들은 내만역에서 외해쪽으로의 분포 경향을 보였으며, 이는 각 정점군의 종조성이 순차적으로 차이가 남을 의미한다. AMBI와 BPI를 이용하여 가로림만의 저서 환경 건강도를 평가한 결과 만 입구역에서는 약간 오염(slightly polluted)된 정도이었으나, 내만역으로 들어갈수록 중간정도의 오염(moderately polluted) 상태를 보여주었다. 우점종의 종조성과 저서건강도 상태를 고려해볼 때, 가로림만의 저서환경은 약간 불안정하고 교란이 진행되고 있는 상태이며, 대규모 양식장들로 인한 유기물오염이 현재 진행되고 있는 것으로 판단된다.

• 한국토양비료학회지
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• 제34권2호
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• pp.77-84
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• 2001

정밀토양조사(精密土壤調査)의 결과 활용도 증진을 위하여, 분포지형(分布地形), 토성(土性), 배수등급(排水等級) 등을 종합한 논 토양의 형태형(形態型)을 구분하였다. 우리 나라 논 토양의 형태형은 37형(型)으로 구분되었고, 분포면적이 많은 형태형은 곡간지 식양질반습답(埴壤質半濕畓)(Lfi : 약 224천ha), 곡간지 식양질 건답(乾畓)(Lfd : 약160천ha), 곡간지 사양질(砂壤質) 반습답(半濕畓)(Lmi : 약112천ha), 곡간지 역질건답(礫質乾畓)(Lkd : 약 93천ha)등의 순으로 곡간(谷間) 및 선상지(扇狀地) 토양의 비중이 높았다. 논 토양의 답리작, 비닐하우스, 또는 녹비배재 가능성등을 형태형별로 추천하였고, 아울러 생고나 퇴비, 심경, 객토 또는 배수 대상지, 침식위험성, 벼의 중간낙수 필요성, 환원장해 우려정도 등을 구분하여 관리기술로 추천하였다. 각종 시험연구가 진전(進展)될수록 더욱 정밀(精密)한 토양관리(土壤管理) 기술의 추천이 가능해질 것으로 본다.

• Journal of the korean society of oceanography
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• 제33권3호
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• pp.71-79
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• 1998

Silty tidal rhythmites were found from the upper Pleistocene sequence unconformably overlain by the Holocene tidal deposits within the macrotidal coastal zone of Youngjong Island, western coast of Korea. The rhythmites occur as vertically accreted, parallel and planar laminae that are 0.1-2.5 mm in thickness. Each lamina grades from coarse silt (mean grain size: 5-6.5 ${\phi}$) at the lower part into fine silt to mud (mean grain size: 6-7.5 ${\phi}$) at the upper part. The rhythmites can be classified into two types based on the patterns in laminar thickness variation. Type I is a bundle of 12-20 laminae in which laminar thickness varies sinusoidally. Type ll is an alternation of thick and thin laminae as a couplet. Type I is inferred as a product of varying tidal energy during a semimonthly (neap-spring) tidal cycle, in which thicker laminae were deposited during spring tides and thinner laminae were formed during neap tides. Type ll is interpreted to have been formed by asymmetric semidiurnal tidal currents in association with diurnal inequality, whereby thick lamina of each couplet represents dominant tidal current and the thin lamina reflects subordinate tidal current.

• 한국대기환경학회지
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• 제26권3호
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• pp.265-275
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• 2010

Mass and ion concentrations of $PM_{10}$ and $PM_{2.5}$ were measured in Yongin, downwind of the Seoul metropolitan area. Twenty-four hour average samples were collected daily for a month or so in spring and fall of both 2007 and 2008. Asian dust occurred twice in each period except in the fall of 2007. During the Asian dust period, nitrate in fine particles decreased since large amount of cations in coarse particles of Asian dust absorbed it. In spring 2008, sulfate as well as ammonium also increased in coarse particles. In spite of occasional Asian dust events, the influence of secondary formation was dominant over the period. Excessive ammonium over sulfate was enough to neutralize nitrate as well. High correlation coefficients between $K^+$ and sulfate, nitrate, and ammonium indicate a close relationship between secondary formation and biomass burning. Biomass burning and open burning are considered to be important sources of chloride.

• 환경영향평가
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• 제16권6호
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• pp.421-432
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• 2007

To investigate temporal and spatial variations of hydrodynamics and environmental conditions in Gyeonggi Bay, including Han River estuary, numerical experiments were performed using 3-dimensional fine grid numerical ocean model. The model successfully reproduced the physical phenomena already known in Gyeonggi Bay where tide and fresh water discharge are dominant forcings. The calculated harmonic constants of tide and tidal current agreed well with those of observations at nine tide stations and two tidal current stations. Tidal asymmetries along the Yeomha Waterway, mainly caused by non-linear effect, were well reproduced and agreed well with observations. Time series of salinity at four stations(A, B, C and D) and horizontal distributions of monthly averaged salinity show that Gyodong and Seokmo Waterways play an important role in fresh water discharge into the Gyeonggi Bay rather than Yeomha Waterway.

• 한국산학기술학회논문지
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• 제12권6호
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• pp.2872-2878
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• 2011

2010년 여름철 만리포의 수질은 COD(화학적산소요구량)가 개장전부터 폐장 이후까지 지속적으로 2.0 mg/l 이하로 측정되어 양호한 상태였고 SS(부유물질)의 량이 7월 조사에서 30mg/l를 초과하였으나 해수욕에는 무리가 없었을 것으로 판단된다. 식물플랑크톤은 대발생이나 적조 등의 현상이 나타나지 않았다. 대천의 수질은 8월 조사에서 COD값이 평균 2.0mg/l를 초과하기도 하였으나 전체적으로는 2.0mg/l 이하로 나타나 역시 해수욕장 수질로서는 양호하다. 다만 SS가 전체적으로 다소 높은 값을 보이기는 하나 이는 대천해수욕장의 저질특성에 기인한 머드(뻘)의 영향인 것으로 보이며 해당 해수욕장의 특징으로 설명될 수 있다. 식물플랑크톤 역시 규조류가 우점하는 보편적인 해수의 특징을 보였다.

• ETRI Journal
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• 제28권1호
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• pp.59-66
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• 2006

Learning behaviors of a radial basis function network (RBFN) using a singular value decomposition (SVD) and stochastic gradient (SG) algorithm, together named RBF-SVD-SG, for odor sensing systems are analyzed, and a fast training method is proposed. RBF input data is from a conducting polymer sensor array. It is revealed in this paper that the SG algorithm for the fine-tuning of centers and widths still shows ill-behaving learning results when a sufficiently small convergence coefficient is not used. Since the tuning of centers in RBFN plays a dominant role in the performance of RBFN odor sensing systems, our analysis is focused on the center-gradient variance of the RBFN-SVD-SG algorithm. We found analytically that the steadystate weight fluctuation and large values of a convergence coefficient can lead to an increase in variance of the center-gradient estimate. Based on this analysis, we propose to use the least mean square algorithm instead of SVD in adjusting the weight for stable steady-state weight behavior. Experimental results of the proposed algorithm have shown faster learning speed and better classification performance.

• Journal of Genetic Medicine
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• 제10권2호
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• pp.81-87
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• 2013

Pseudohypoaldosteronism (PHA), a rare syndrome of systemic or renal mineralocorticoid resistance, is clinically characterized by hyperkalemia, metabolic acidosis, and elevated plasma aldosterone levels with either renal salt wasting or hypertension. PHA is a heterogeneous disorder both clinically and genetically and can be divided into three subgroups; PHA type 1 (PHA1), type 2 (PHA2) and type 3 (PHA3). PHA1 and PHA2 are genetic disorders, and PHA3 is a secondary disease of transient mineralocorticoid resistance mostly associated with urinary tract infections and obstructive uropathies. PHA1 includes two different forms with different severity of the disease and phenotype: a systemic type of disease with autosomal recessive inheritance (caused by mutations of the amiloride-sensitive epithelial sodium channel, ENaC) and a renal form with autosomal dominant inheritance (caused by mutations of the mineralocorticoid receptor, MR). In the kidneys, the distal nephron takes charge of the fine regulation of water absorption and ion handling under the control of aldosterone. Two major intracellular actors necessary for the action of aldosterone are the MR and the ENaC. Impairment of the intracellular aldosterone signal transduction pathway results in resistance to the action of mineralocorticoids, which leads to PHA. Herein, ion handling the distal nephron and the clinico-genetic findings of PHA are reviewed with special emphasis on PHA type 1.

• 자원환경지질
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• 제14권1호
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• pp.35-49
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• 1981

The studied area is largely occupied by thick piles of the late Cretaceous volcanic rocks of the Yucheon group, which is northeastern border part of the vast volcanic region in the Yucheon basin. The Yucheon group overlies the Geoncheonri Formation and is intruded by granitic and dioritic stocks and dykes. The group can be devided into two parts; the lower is Jusasan andesitic rocks which was called as Jusasan Porphyrite Formation by Tadeiwa in 1929, and the upper is Unmunsa rhyolitic rocks. The volcanic pile consists mainly of various tuffs such as tuff breccia, lapilli tuff, coarse to fine tuff and tuffaceous sediments, and interlayered flows, which range from basaltic andesite to rhyolite in their lithology. The results of petrochemical and volcanostratigraphic studies on the Jusasan andesitic socks suggest that the volcanic rocks were derived from two cyclic evolutions of magmatic fractionation. Systematic study of 5226 joints from the area reveals two sets of steep joints striking $N20^{\circ}-40^{\circ}E$ and $N40^{\circ}-70^{\circ}W$, are dominant and coincide with the fault pattern developed in the area. Three defferent maximum principal stress axes were recognized from conjugate shear joints, which are trending east-west, north-northwest, and north-northeast.

• Applied Microscopy
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• 제24권2호
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• pp.1-11
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• 1994

The book lung in the wolf spider, Pardosa astrigera was consisted of a series of flattened triangular-shaped air sacs, stacked with about 70 sheets, and was located in the ventrolateral region of opisthosoma. Each hemolymph spaces (average $8{\mu}m$ in thickness) surrounded by the air sacs (average $6{\mu}m$ in thickness). The air sacs was supported by cylindrical cuticular spikes of microfibril bundles. Epithelial cell processes surrounded the hemolymph spaces. The nuclei of the epithelial cells were concentrated near the atrium. In the middle portion of air sac, the epithelial cells formed pillars across the hemolymph spaces and spot desmosome and zonula adherens were seen between the plasma membranes. In the hemolymph space of this spider, granular hemocytes (average diameter $8{\mu}m$) were the most dominant type of hemocytes. In the medial sinus, the hemolymph flow between the air sacs of a paired book lungs and then flow out of the lung vein. The air comes in the atrium through the ventral lung slit and makes a tidal wave in and out of the air sacs.