• 한국정보통신학회논문지
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• 제17권5호
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• pp.1055-1063
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• 2013

전자파 내성 및 전자파 장해 측정을 위한 표준 전자파 발생 장치 중 하나인 CTL cell에서 두 개의 입력 단자에 동일 신호와 역위상 신호 입력에 따른 다양한 전계와 자계 발생에 대해 살펴보았다. 기본 공진주파수 TE011이 2.20GHz인 CTL cell을 이용하여 우세 전계장과 우세 자계장 조건에서 입력 전력의 변화에 따른 전계 특성, 측정 위치에 따른 전계 특성, 주파수 변화에 따른 전계 특성을 측정하였고, 이를 이용하여 CTL cell의 측정 영역에서의 동작 특성과 공진주파수의 영향을 받지 않고 사용 가능한 주파수 대역을 살펴보았다.

• 천문학회보
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• 제40권1호
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• pp.58.2-58.2
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• 2015

We investigate the decaying incompressible MHD turbulence by including the effect of the expansion and contraction of background medium. In such an environment, incompressible MHD turbulence has two kinds of time scale. One is the eddy turn-over time (teddy), the other is the expansion/contraction time (texp-cntr). The turbulence is expected to behave differently according to the relationship between the two time scales. For instance, for teddy < texp-cntr, the turbulence would be decay more or less as in a static medium. On the other hand, for teddy > texp-cntr, the effects of expansion and contraction would be dominant. We examine the properties of turbulence in these two regime cases. Based on it, we derive a scaling for the time evolution of flow velocity and magnetic field. (i) In the decay effect dominant case, the velocity and magnetic field scale as $\sqrt{{\rho}v}{\sim}a^{-3}$, $b{\sim}a^{-2.5}$(expanding media) and $\sqrt{{\rho}v}{\sim}a^{-2}$, $b{\sim}a^{-1.5}$(contracting media). The total energy and residual spectra follow the $E^T_k{\sim}k^{-5/3}$, $E^R_k{\sim}k^{-7.3}$ in the inertial range. (ii) In the expanding and contracting dominant case, the velocity and magnetic field scale as $\sqrt{{\rho}v}{\sim}a^{-2.5}$, $b{\sim}a^{-2}$ (expanding/contracting media). The Kinetic and magnetic energy spectra follow the $E^K_k{\sim}a^{-5}$, $E^M_k{\sim}a^{-4}$. We have confirmed that scaling of velocity and magnetic filed is almost the same from the analytic estimates and computational models

• 대한전자공학회논문지
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• 제26권8호
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• pp.1145-1151
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• 1989

New method to calculate the characteristics of the dominant and higher order modes of waveguide latching phase shifters are presented. Due to the tensor permeability, E and H fields inside the ferrite are expanded in terms of the LSE and LSM eigenmodes of the dielectric-slab-loaded waveguide. The equivalent coupled transmission line equations on the transverse plane are derived to obtain the dispersion characteristics and the E and H field distributions. Numerical results at X-band are compared with those published previously. The derived field distributions can be used to suppress the higher order modes of the latching phase shifters, so that the phase shift from the dominant mode only contributes the performance of the phase shifters.

• 자원환경지질
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• 제32권1호
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• pp.19-31
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• 1999

In this study, we have estimated lineaments in the Euiseong area, Kyungbuk Province, from Landsat TM by applying the algorithm developed by Kim and Won et al. which can effectively reduce the look direction bias associated with the Sun's azimuth angle. Fratures over the study area were also mapped in the field at 57 selected sites to compare them with the results from the satellite image. The trends of lineaments estimated from the Landsat TM images are characterized as $N50^{\circ}$~70W, NS~$N10^{\circ}$W, and $N10^{\circ}$~$60^{\circ}$E trends. The spatial distribution of lineaments is also studied using a circular grid, and the results show that the area can be divided into two domains : domain A in which NS~$N20^{\circ}$E direction is dominant, and domain B in which west-north-west direction is prominent. The trends of lineaments can also be classified into seven groups. Among them, only C, D and G trends are found to be dominant based upon Donnelly's nearest neighbor analysis and correlations of lineament desities. In the color composite image produced by overlaying the lineament density map of these C-, D-, and G-trends, G-trend is shown to be developed in the whole study area while the eastern part of the area is dominated by D-trend. C-trend develops extensively over the whole are except the southeastern part. The orientation of fractures measured at 35 points in the field shows major trends of NS~$N30^{\circ}$E, $N50^{\circ}$~$80^{\circ}$W, and N80$^{\circ}$E~EW, which agree relatively well with the lineaments estimated form the satellite image. The rose diagram analysis fo field data shows that WNW-ESE trending discontinuities are developed in the whole area while discontinuities of NS~$N20^{\circ}$E are develped only in the estern part, which also coincide with the result from the satellite image. The combined results of lineaments from the satellite image and fracture orientation of field data at 22 points including 18 minor faults in Sindong Group imply that the WNW-ESE trend is so prominent that Gumchun and Gaum faults are possibly extended up to the lower Sindong Group in the study area.

• 환경위생공학
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• 제5권1호
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• pp.54-62
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• 1990

충청북도 일원에서 1976년부터 1981년사이에 산불이 발생한 산화적지와 그에 인접한 비산화지의 식생과 토양성분을 조사하여, 산화 후의 식생회복과 토양성분과의 관계를 분석한 결과는 다음과 같다. 1. 79-B의 우점종 순위가 억새-산거울-싸리의 순으로 비산화지와 같게 나타나 산화 후 2년째 회복되었고, 그 후 산화적지에서 싸리가 점차 우점종으로 발달하여 산화 후 5년이 지난 76-B의 우점종 순위가 싸리-산거울-억새의 순이었다. 2. 생활형 조성은 산화 후 2년째부터 조사지소에 따라 H-e-$D_1-R_5$ 또는 Ph-e-$D_1-R_5$로 산화적지와 비산화지가 같게 되어, 산화 후 2년째에 산화적지의 생활형이 회복되었다. 3. 천이도는 81-B의 DS=423, 81-U의 DS=524로 산화적지가 낮았으나, 산화 후 2년째인 79-B의 DS=510, 79-U의 DS=520으로 거의 같았고, 산화 후 3년째부터는 산화적지가 비산화지보다 점차 높게 나타나 산화적지는 비산화지보다 천이가 빠르게 진행됨을 알 수 있다. 4. Shannon-Wiener function, Morishita's index 및 Simpson's index 등 종 다양성의 분석 결과에 의하면, 산화 당년에는 복잡한 군집이었으나 산화 후 2~3년째에 비산화지와 같은 단순한 군집으로 회복되었다. 또한 Evenness index의 분석 결과, 산화 당년에 식물종수가 비산화지보다 많았으나 산화 후 2년째부터 비산화지와 같은 종수가 되었다. 6. 산화적지의 식생은 산화 후 2~3년째에 비산화지의 식생과 거의 같게 회복되었고, 토양성분도 2~3년째에 회복되었다. 따라서, 산화 후 식생회복 과정과 토양성분의 변화사이에는 밀접한 관련이 있었다.

• 한국잡초학회지
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• 제17권1호
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• pp.1-9
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• 1997

효과적(效果的) 잡초방제(雜草防除) 체계확립(體系確立)을 위한 기초자료(基礎資料)로서 1995년 경기도(京幾道) 벼 식부면적(植付面積) 131,130ha를 대상(對象)으로 약 400ha당 1점씩 기준(基準)하여 340개 지점(地點)에서 답류형(畓類型), 이앙기(移秧期) 및 농업지대별(農業地帶別)로 구분(區分)하여 실시(實施)한 잡초분포(雜草分布) 조사결과(調査結果)와 '81년, '91년, '95년의 시기별(時期別) 잡초군락(雜草群落) 변화(變化)를 요약(要約)하면 다음과 같다. 1. 잡초방제(雜草防除)는 1회(回) 처리(處理)와 2회(回) 이상(以上) 체계처리(體系處理) 농가(農家) 비율(比率)이 34 : 66으로 '91년에 비하며 체계처리(體系處理) 농가(農家) 비율(比率)이 11% 증가(增加)하였으며, 1회(回) 처리(處理) 농가(農家) 중 Butachlor G. 처리농가(處理農家) 비율(比率)은 25%로 가장 높았다. 2. Butachlor G. 처리답(處理畓)에서는 일년생(一年生)보다 다년생잡초(多年生雜草) 분포비율(分布比率)이 높았으며, '91년에 비해 일년생잡초(一年生雜草) 분포비율(分布比率)이 감소(減少)하였다. 3. 잡초분포(雜草分布)는 화본과(禾本科) 3종(種), 방동산이과(科) 5종(種), 광엽(廣葉) 및 기타(其他) 14종(種) 등(等) 총(總) 22종(種)이였으며, $m^2$당(當) 잡초본수(雜草本數)는 20.4개(個)였고, 잡초건물중(雜草乾物重)은 5.9g으로 초종분포(草種分布)가 '91년의 25종(種)보다 적었으며 잡초발생량(雜草發生量)도 감소(減少)하였다. 4. 일년생(一年生)가 다년생잡초(多年生雜草) 분포(分布) 비율(比率)은 38 : 62로 다년생잡초(多年生雜草)가 많아 '81년 분포(分布)와 비슷하였으나 '95년에 비하여 다년생잡초(多年生雜草) 분포비율(分布比率)이 낮았다. 5. 주요(主要) 우고초종(優古草種)은 벗풀>올방개>피>가막살이>물달개비 순(順)으로 '81년의 물달개비>가래>너도방동산이>올미 및 '91년의 올방개>벗풀>피>너도방동산이>물달개비 순과는 다르게 나타났으며, '91년에 비하여 일년생잡초(一年生雜草) 피의 우점비율(優占比率)이 높아졌다. 6. 답유형별(畓類型別) 잡초발생량(雜草發生量)은 보통답(普通畓)>습답(濕畓)>염해답(鹽害畓) 순(順)이었다. 보통답(普通畓)에서는 벗풀>올방개 >피>가막살이, 습답(濕畓)에서는 벗풀>올방개>피>여뀌 순(順), 염해답(鹽害畓)에서는 새섬매자기>벗풀>올방개 순으로 나다났다. 7. 이앙기별(移秧期別) 잡초분포상태(雜草分布狀態)는 이앙기(移秧期)가 늦을수록 잡초발생량(雜草發生量)이 증가(增加)하였으며 5월 이앙답(移秧畓)에서는 벗풀>올방개>피>물달개비 6월 이앙답(移秧畓)에서는 올방개>벗풀>너도방농산이 순(順)으로 우점초종분포(優占草種分布)가 다르게 나다났다. 8. 경운방법별(耕耘方法別) 잡초발생량(雜草發生量)은 무경운이앙(無耕耘移秧)>추경(秋耕)>춘경(春景) 순(順)이었으며, 추경답(秋耕畓)에서는 벗풀>올방개>피>물달개비, 춘경답(春景畓)에서는 벗풀>올방개>피>가막살이, 무경운(無耕耘) 이앙답(移秧畓)에서는 피>올챙이고랭이>벗풀 순(順)으로 우점(優占)하였다. 9. 농업지대별(農業地帶別) 우점초종(優占草種)은 남부평야지대(南部平野地帶)는 피>올방개>벗풀>새섬매자기, 서부해안지대(西部海岸地帶)에서는 피>벗풀>올방개, 동부내륙지대(東部內陸地帶)에 벗풀>올방개>사마귀풀 순(順)으로 다르게 나타났다.

• 한국제4기학회지
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• 제17권2호
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• pp.123-128
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• 2003

This study was conducted to examine the water use efficiency (WUE) in five species of one-year-old seedlings grown in a field nursery in Mongolia. Larix sibirica and Pinus sylvestris are the most dominant coniferous species while Ulmus pumila is an important deciduous species known well-adapted in harsh conditions such as in semi-arid forests and Gobi desert regions. Caragana arborescens (Siberian pea shrub) and Hippophae rhamnoides are N-fixing shrubs in Mongolia. Thirty one-year-old seedlings were sampled from each of the five species (a total of 150 samples) and measured for net photosynthetic rate (Pn) and transpiration rate (E). The Pn and E were used to calculate and compare the WUE of each species. Pn differed significantly among the five species (p < 0.05). However, there was no significant difference in Pn between L. sibirica and H. rhamnoides (p > 0.05). C. arborescens showed the highest Pn whereas U. pumila did the poorest. E differed significantly among the five species (p < 0.05). L. sibirica and U. pumila showed considerably lower E than other species. Thus, WUE values of coniferous species such as L. sibirica and P. sylvestris were significantly greater than deciduous or shrub species such as U. pumila, C. arborescens and H. rhamnoides (p < 0.01). It may result that conifers showed relatively high water use efficiency than deciduous or shrub trees due to their lower transpiration rates, which resulted in morphological and physiological characteristics of their leaves. This may indicate that L. sibirica and P. sylvestris can be widely used for rehabilitation works in Mongolia attributed to their dominant distributions but also their high drought-resistance properties.

• E2M - 전기 전자와 첨단 소재
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• 제10권5호
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• pp.453-460
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• 1997

In order to investigate the electrical conduction properties of polyethylene thin film for power cable with manufacturing methods, the thickness of specimen was the 30, 100[${\mu}{\textrm}{m}$] of LDPE and 200[${\mu}{\textrm}{m}$] of XLPE were manufactured. The experimental condition for conduction properties was measured until the breakdown occurs at temperature ranges from 30 to 110[$^{\circ}C$] and the electric field from 1$\times$10$^3$to 5$\times$10$^{6}$ [V/cm]. As for increase of temperature, the current density of LDPE was increased with constant ratio in low field, but changes with exponential function in high electric field. The tunnel current of pre-breakdown region is shifted toward low field as much as thermal excitation energy. At low electric field, the XLPE showed dominant electrical conduction properties by thermal excitation, and transformation of the electron was resisted by the crystal at high electric field.

• JSTS:Journal of Semiconductor Technology and Science
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• 제8권2호
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• pp.164-169
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• 2008

The effects of the antisite related defects on the electronic structure of silica and the gate leakage current have been investigated using first-principles calculations. Energy levels related to the antisite defects in silicon dioxide have been introduced into the bandgap, which are nearly 2.0 eV from the top of the valence band. Combining with the electronic structures calculated from first-principles simulations, tunneling currents through the silica layer with antisite defects have been calculated. The tunneling current calculations show that the hole tunneling currents assisted by the antisite defects will be dominant at low oxide field whereas the electron direct tunneling current will be dominant at high oxide field. With increased thickness of the defect layer, the threshold point where the hole tunneling current assisted by antisite defects in silica is equal to the electron direct tunneling current extends to higher oxide field.

• Clinical and Experimental Pediatrics
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• 제57권1호
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• pp.1-18
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• 2014

Channelopathies are a heterogeneous group of disorders resulting from the dysfunction of ion channels located in the membranes of all cells and many cellular organelles. These include diseases of the nervous system (e.g., generalized epilepsy with febrile seizures plus, familial hemiplegic migraine, episodic ataxia, and hyperkalemic and hypokalemic periodic paralysis), the cardiovascular system (e.g., long QT syndrome, short QT syndrome, Brugada syndrome, and catecholaminergic polymorphic ventricular tachycardia), the respiratory system (e.g., cystic fibrosis), the endocrine system (e.g., neonatal diabetes mellitus, familial hyperinsulinemic hypoglycemia, thyrotoxic hypokalemic periodic paralysis, and familial hyperaldosteronism), the urinary system (e.g., Bartter syndrome, nephrogenic diabetes insipidus, autosomal-dominant polycystic kidney disease, and hypomagnesemia with secondary hypocalcemia), and the immune system (e.g., myasthenia gravis, neuromyelitis optica, Isaac syndrome, and anti-NMDA [N-methyl-D-aspartate] receptor encephalitis). The field of channelopathies is expanding rapidly, as is the utility of molecular-genetic and electrophysiological studies. This review provides a brief overview and update of channelopathies, with a focus on recent advances in the pathophysiological mechanisms that may help clinicians better understand, diagnose, and develop treatments for these diseases.