• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.04a
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• pp.27-27
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• 2019

본 연구는 한국 특산식물이고, IUCN Red List의 EN(위기종) 등급에 속하는 개느삼(Echinosophora koreensis)을 대상으로 자생지 분포, 식생구조 등의 생태적 특성과 현지 내외 보전 방안을 제시하기 위해 수행되었다. 개느삼의 자생지 분포 조사 결과 강원도 양구군 13곳, 인제군 3곳, 춘천시 2곳, 홍천군 1곳 총 19곳에 분포하는 것을 확인하였다. 개느삼 자생지의 해발고도는 169-711m에 분포하는 것으로 나타났고, 평균 해발고도는 375m 인 것으로 조사되었다. 개느삼 자생지의 면적 조사 결과, $8,000-734,000m^2$인 것으로 분석되었고, 평균 $202,789m^2$으로 조사되었다. 개느삼 자생지의 입지환경 분석을 수행한 결과, 자생지 내 우점종은 교목층에서 소나무가 대부분 우점하였고, 아교목층에서는 신갈나무가 우점하는 것으로 분석되었다. 관목층은 생강나무가 우점하였고, 초본층은 모든 조사구에서 개느삼이 우점하는 것으로 분석되었다. 개느삼 자생지의 식생군집분석 결과, 신갈나무, 소나무, 굴참나무 우점 군집 3개 군집으로 분류되었다. 개느삼 자생지를 대상으로 관속식물상을 조사한 결과, 총 82과 204속 289종 4아종 43변종 5품종 341분류군으로 확인되었다. 개느삼의 출현지점을 이용하여 자생지 분포역 예측 model 중 하나인 MaxEnt 분석을 통하여 잠재 분포지 분석을 수행한 결과, AUC값은 0.9762로 분석되었다. 분포예측 자생지는 강원도 양구군, 인제군, 춘천시, 화천군 지역에 집중되어 분포하는 것으로 나타났다.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.24 no.11
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• pp.1055-1063
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• 2013

Low noise amplifiers(LNAs) are an integral component of RF receivers and are frequently required to operate at wide frequency bands for various wireless systems. For wideband operation, important performance metrics such as voltage gain, return loss, noise figures and linearity have been carefully investigated and characterized for the proposed LNA. An inductive shunt feedback configuration is successfully employed in the input stage of the proposed LNA which incorporates cascaded networks with a peaking inductor in the buffer stage. Design equations for obtaining low and high input matching frequencies are easily derived, leading to a relatively simple method for circuit implementation. Careful theoretical analysis explains that poles and zeros are characterized and utilized for realizing the wideband response. Linearity is significantly improved because the inductor between gate and drain decreases the third-order harmonics at the output. Fabricated in $0.18{\mu}m$ CMOS process, the chip area of this LNA is $0.202mm^2$, including pads. Measurement results illustrate that input return loss shows less than -7 dB, voltage gain greater than 8 dB, and a little high noise figure around 7~8 dB over 1.5~13 GHz. In addition, good linearity(IIP3) of 2.5 dBm is achieved at 8 GHz and 14 mA of current is consumed from a 1.8 V supply.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.5 no.2
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• pp.169-176
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• 2000

This study was carried out to clarify the spatial and temporal patterns of macrobenthic assemblages on the subtidal area around Mokpo, southwest of Korea. A total of 238 species and 663 ind./$m^{2}$ were collected. Polychaetes were the most abundant faunal group that comprised 88 species and had a mean density of 389 ind./$m^{2}$. In the semi-enclosed Youngsan River estuarine bay and neighbouring Mokpo Port area were composed of fine sediments with high organic content, and revealed large seasonal variations in the salinity of surface water and bottom dissolved oxygen in contrast to little seasonal changes in those parameters in the outer area. The study area was classified into four station groups by the cluster analysis; the harbor area, the offshore area, and the inner and outer estuarine bay. Two estuarine bay areas showed different species composition; the dominant species of inner bay were Tharyx sp., Poecilochaetus johnsoni, Heteromastus filiformis and other opportunistic species whereas those in the outer bay were Ruditapes philippinarum, Corophium sinense. From the environmental data and species composition of benthic community, the inner bay was characterized to have unstable benthic faunal assemblages, especially under the seasonal disturbance and receiving large amount of organic matter input and intermittant discharge of fresh water. The coastal developments around Mokpo city also seem to have stressed the subtidal communities spatio-temporally.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.7
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• pp.440-447
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• 2019

The purpose of this study was to identify the relationship between leisure function, self-esteem and social role loss among golf players in the middle age. Furthermore, it was meaningful to provide basic data on leisure activities and healthy retirement preparation through golf at the present time of the aging society. The subjects of study who adults were recruited from Seoul, Gyeonggi-do. For the data processing, it conducted frequency, reliability, confirmatory factor, correlation, and structure equaling modeling analyses. The results were as follows; First, leisure function of middle age golf participant had a positive influence on self-esteem(p<.05). Second, leisure function of middle age golf participant had a positive influence on social role loss(p<.05). Third, self-esteem of middle age golf participant had a positive influence on social role loss(p<.05). Forth, self-esteem mediated the relationship between middle age golf participant leisure function and social role loss.(p<.05).

• Journal of Korean Elementary Science Education
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• v.42 no.1
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• pp.93-108
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• 2023

This study aims to analyze the types and roles of visualization materials presented in the third- and fourth-grade national and authorized science textbooks based on the 2015 revised curriculum. Using the type and role framework, 17 chapters were analyzed. The analysis revealed, first, that the national and authorized textbooks had different total amounts of visualization data and total amounts of simple illustrations. However, no difference in the amounts of simple illustrations and infographics used in the units was evident. The units that used the most infographics were Life, Earth and Universe, in that order, in both the national and the authorized textbooks. Second, simple illustrations were observed to have role differences according to the type of visualization data, but infographics had no such differences. Specifically, the motivational role in a simple illustration increased in all the authorized textbooks. Third, looking at the frequencies of the infographic subtypes, the Process, Structure, Comparative Analysis, and Timeline types accounted for 86% of the total, but the proportions of those subtypes varied in the national and authorized textbooks. Based on the results of this study, I suggest that to achieve differentiation in the types or roles of visualization materials, changes in the types, processes, and skills of inquiry must first occur, as must changes in the structure of chapters or lessons. Continuous research and discussion on the standards and methods for authorized textbooks are also needed.

• Korean Journal of Logic
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• v.20 no.1
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• pp.21-67
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• 2017

In this paper, I critically examine Sartorio's (2006) argument for disjunctive cause, and put forth disjunctive causal structure in a different way. I show that the disjunctive causal structure meets not just what Sartorio means to claim but also our understanding of causal responsibility. First, I introduce Sartorio's argument for disjunctive cause. Second, I critically discuss Sartorio's responses to the criticisms of her arguments for disjunctive cause, and propose another problem with her arguments. Finally, I explicate in a different way Sartorio's disjunctive cause in terms of disjunctive causal structure founded on moderate variables, causal interaction, and probability trajectory. I notice, regarding the disjunctive causal structure, the role of causal interaction of cause events with moderate variables. I reveal, regarding the disjunctive causal structure, the significance of indetermination of cause events and effect events for our understanding of causal responsibility. I show that the disjunctive causal structure guides us more convincingly to assign causal responsibility to an agent. I come to three conclusions. First, there is no disjunctive cause event Sartorio argues for. Second, propensities of events to be causally connected to an effect event constitute disjunctive relation. Third, we should notice indetermination of cause events and effect events while assigning causal responsibility to an agent.

• Journal of Ecology and Environment
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• v.29 no.3
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• pp.247-252
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• 2006

For the spring ephemeral and myrmecochorous perennia, Corydalis filistipes Nakai (Fumariaceae), rare and narrow endemic to Ullung Island in Korea, genetic diversity and structure of 4 subpopulations of the species were investigated with allozyme markers. Levels of genetic diversity (A=1.73, $P_{95%}$=61..2%, Ho=0.201, He=0.167) were relatively lower than those of other endemic species with widespread distribution range, but considerably higher than other endemic species with similar life history traits isolated in island. The moderate level of genetic diversity within subpopulations in C. filistipes is characteristic of the species with predominantly outcrossing, myrmecochorous seed dispersal by dual function of the elaisome and mode of sexual and asexual reproduction by the cleistogamy. The analysis of fixation indices showed an overall excess of heterozygotes (mean $F_{IS}=-0.1889,\;F_{IT}=-0.1226$) relative to H-W expectations. About 5.6% of the total genetic variation was found among subpopulations ($F_{ST}$=0.0557). The strategies of reasonable conservation and management, and the maintenance mechanism of genetic diversity of Corydalis filistipes Nakai, endemic plant species in Korea were discussed.

• Journal of the Korea institute for structural maintenance and inspection
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• v.13 no.1 s.53
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• pp.106-114
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• 2009

The steel design based on the width of transverse crack which is the major factor to affect a long-term performance of continuously reinforced concrete pavement was developed. For this study, twenty-one cities of Texas were selected and the temperature data was collected at those locations during the past ten years. From the data, zero-stress temperatures were calculated by the PavePro program and the widths of transverse crack were analyzed by the CRCP program. The variables used to this numerical analysis were slab thickness, coefficient of thermal expansion of concrete, steel ratio, and design temperature. The total of 448 factorial runs were made and the regression analysis was performed using the results. Steel ratios from the regression equations were backcalculated and a steel design table was proposed.

• Journal of Music and Human Behavior
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• v.7 no.1
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• pp.61-77
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• 2010

As a means to support maternal transition, a home-based music intervention was employed to facilitate mothers' singing to their infants. Four mothers were recruited as volunteers for this study their typically developing infants ranged in age from 2 months to 11 months. Interviews were conducted after the completion of the intervention. An educational music intervention was used to introduce the benefits of mothers' singing to their infants and to encourage four mothers to perform regular singing to their infants for the two-week period. In the interview, mothers provided valuable information regarding their personal experiences, thoughts, abilities to carry out the daily singing, and additional support needs in singing. All mothers demonstrated positive experiences and needs for future intervention development. Overall, the results showed that music-involved educational intervention is beneficial for mothers to support their maternal transition. The need emerged for future studies to develop music-involved educational intervention to support maternal transition.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.31-31
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• 2009

PECVD를 이용하여 제조된 미세결정질 p-i-n 실리콘 박막 태양전지에서, p 층은 태양전지의 윈도우 역할 및 그 위에 증착될 i ${\mu}c-Si:H$ 층의 'seed'층 역할을 수행하기 때문에, p층의 구조적 및 전기적, 광학적 특성은 태양전지의 전체 성능에 큰 영향을 미칠 수 있다. 본 연구에서는 $SiH_4$ 농도를 변화시켜 각기 다른 결정 특성을 갖는 p ${\mu}c-Si:H$층을 제조하고 그 위에 i ${\mu}c-Si:H$ 층을 증착하여 p층의 결정 특성변화와 그에 따른 i ${\mu}c-Si:H$ 층 및 'superstrate' p-i-n 미세결정질 실리콘 박막 태양전지의 특성 변화를 조사하였다. P층의 경우, $SiH_4$ 농도가 증가함에 따라 결정분율 (Xc)이 감소하여 비정질화되었으며 그에 따라 dark conductivity가 감소하는 경향을 나타내었다. 각기 다른 결정분율을 가지는 p 'seed' 층 위에 증착된 태양전지는, p 'seed' 층의 결정분율이 증가함에 따라 개방전압, 곡선인자, 변환효율이 경향적으로 감소하였다. 이는 p 층 결정분율 변화에 따른 p/i 계면특성 저하 및 그 위에 증착되는 i ${\mu}c-Si:H$ 층의 결함밀도 증가 등에 따른 태양전지 특성 감소 때문인 것으로 판단되며, 이를 분석하기 위하여 i ${\mu}c-Si:H$ 층의 전기적, 구조적 특성 분석 및 태양전지의 dark I-V 특성 등을 분석하고자 한다.