• JOURNAL OF ELECTRICAL WORLD
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• s.263
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• pp.67-78
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• 1998

최근 파워일렉트로닉스기술의 급속한 진보로 인버터 응용기기가 폭넓은 분야에 이용되어 자에너지화에 크게 기여하고 있다. 그러나 반면에 이들 기기로 부터는 전기의 공해라고도 할 수 있는 고조파전류가 발생하고 있다. 이와 같은 배경에서 $\ulcorner$고압 또는 특별고압으로 수전하는 수용가의 고조파 억제대책 가이드라인$\lrcorner$이 제정되어 앞으로 인버터 기기류를 다수 설치하는 수용가에서는 고조파억제대책을 세워야 하는데 그 기기로서 액티브 필터(Active Filter)가 주목을 받고 있다. 액티브 필터는 $\cdot$고속응답성을 갖춘 IGBT(Insulted Gate Bipolar Transistor)소자를 사용한 인버터에 의하여 여러 가지 고조파를 한번에 억제할 수 있다. $\cdot$IGBT소자의 채용에 의한 소형화로 자스페이스$\cdot$저소음화를 실현할 수 있다. $\cdot$액티브 필터는 전원계통을 변경하더라도 설비특성을 변경할 필요가 없다. $\cdot$액티브 필터는 고조파전류가 증가하여도 과부하가 되는 일이 없다. 등 기존의 L-C필터(패시브 필터)에는 없는 우수한 특징을 갖추고 있어, 일반제조업 이외에도 테넌트(임대) 빌딩이나 극장(홀)에도 적용시킬 수 있는 고조파대책의 유효한 수단이 되고 있다.

• The Journal of Society for e-Business Studies
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• v.12 no.4
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• pp.165-184
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• 2007

Recently, blogging has been regarded as a promising media for information sharing and relationship building. However, it is not quite sure if the technology acceptance model could be completely adopted also in relationship-based system such as blog. Hence, the purpose of this paper is to identify the factors affecting the usage of blogs. To do so, content analysis methodology is applied to extract meaningful factors affecting the usage of blogs in the opinions of the bloggers in a Korean portal site : Naver. We investigates the causal relationship among three factors ; perceived usefulness, perceived encouragement, and actual use in blogging. Moreover, public self-consciousness, self disclosure and telepresence are also considered as the determinants. The results show that public self-consciousness and self disclosure are significant elements affecting perceived usefulness and perceived encouragement, while perceived usefulness and perceived encouragement both affecting the actual use of blogs.

• Information Systems Review
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• v.18 no.4
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• pp.89-106
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• 2016

The latest movement in live video streaming service is mobile personal broadcasting (MPB), which refers to consumers accessing the service through social media with mobile devices, such as smartphones and tablet PCs. This service is possible through the advancements in mobile video technology and platforms. Features such as enhanced user interaction, personalization, and real-time broadcasting, combined with a greater variety of content, have led to the development of MPB. The increase in MPB users calls for research, including that on the hedonic motivational angle. This study aims to assess MPB users' intrinsic motives through the hedonic-motivation system adoption model (HMSAM) using seven factors: joy, temporal dissociation, escapism, focused immersion, perceived ease of use, perceived usefulness and intention to watch. Survey data collected from 154 samples were analyzed with statistical techniques, such as structural equation modeling. Results showed that time dissociation, escapism, and perceived ease of use have a positive relationship with heightened enjoyment. Joy significantly affects focused immersion and intention to watch. Escapism also had a statistically significant influence on focused immersion. This study contributes to the advancement of the MPB study under the HMSAM theoretical framework and offers practical suggestions to managers to enhance MPB content viewership.

• Journal of the Korean Wood Science and Technology
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• v.25 no.2
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• pp.45-51
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• 1997

주목 잎을 채취하여 건조하고 아세톤-물 (7 : 3, v/v) 의 혼합액으로 추출한 후 에틸아세테이트 및 수용성 부분으로 분리하고 Sephadex-LH 20으로 충진한 칼럼을 이용하여 2개의 flavan 단량체와 2개의 후라보노이드 배당체를 단리하였다. 에틸아세테이트용성 추출물은 대부분 (+)-catechin 과 (-)-epicatechin으로 구성되어 있었으며 수용성 부분에서는 quercetin-3-0-arabinopyranosyl-($1"'{\rightarrow}6"$)-${\beta}$-D-glucoside와 quercetin-3-O-rutinoside 인 두 개의 탄수화물로 구성된 배당체를 분리하였으며 주목에서는 이들 화합물은 아직 보고된 바가 없다. 이들의 구조결정을 위하여 박층크로마토그래피를 실시하고 $^1H$-NMR과 $^{13}C$-NMR 스펙트럼을 기존의 스펙트럼과 비교, 분석하여 정확한 구조를 규명하였다.

• Korea journal of population studies
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• v.27 no.1
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• pp.91-119
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• 2004

독일에서 가족은 전후의 산업화과정 속에서 다면적인 사회변동을 경험하면서 형태적 측면과 내용적 측면에서 다양화와 탈제도화 그리고 개인화의 경향이 강해지는 현상을 보이게 되었다. 이러한 변화과정 속에서 가족은 저출산문제, 보육문제, 역할분담을 둘러싼 갈등, 빈곤과 실업, 노인부양문제 등과 같은 다양한 문제와 직접적으로 당면하게 되었다. 특히 1980년대 후반부터는 통일을 전후로 하여 약 10년간에 걸쳐 저출산문제가 심화되면서 가족문제는 중요한 사회정책이 슈로 부각되기 시작하였다. 이러한 현상은 근대적 가족주의에 기반한 가족의 복지정책의 개선에 대한 사회적 요구를 증대시켰고 그로 인해 독일 가족복지정책은 인구변화로 인해 발생되는 가족의 복지욕구를 수용해야 한다는 과제를 떠안게 되었다. 본 연구는 1950년대 이후부터 현재에 이르기까지 독일에서 시대별로 각 집권정당들은 다양한 가족쟁점들을 어떠한 관점에서 수용하여 정책의제화하고, 이에 대한 대응전략으로써 어떠한 정책방안들을 발전시켜 왔는가 하는 과정적 전개양상을 문헌연구방법을 통해 분석함을 목적으로 하였다. 연구를 통해 획득된 결과는 다음과 같다: 독일의 가족복지정책은 가족쟁점의 변화에 따라 1인 부양자모델의 확립기, 취업모 지원과 가족의 다양성에 대한 정책적 수용기, 보육정책의 확대기로 구분될 수 있으며, 그 과정에서 체계화된 정책 프로그램은 소득지원, 양육 및 교육지원 그리고 노인부양가족지원 프로그램이 핵심을 형성하게 되었다. 이러한 프로그램들의 발전은 정책이 1인 부양자모델에서 2인 부양자모델로 연속적으로 변화되는 양상을 반영하고 있다는 점에서 가족문제의 해결책을 모색 중인 우리나라에도 시사하는 바가 많다.

• Korean Journal of Poultry Science
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• v.31 no.4
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• pp.221-228
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• 2004

This study was conducted to determine the effects of two chemical additives on nitrogen (N) and soluble reactive phosphorus (SRP) contents in litter (rice hull) after broiler chicks were raised for 42 days. Two different additives were applied as a top dressing to the litter at a rate of 200 g ferrous sulfate $(FeSO_4)$ or 200 g aluminum sulfate [$Al_2(SO_4)_3$ $\cdot$ $14H_2O$, Alum] per kg litter, while the control group did not have the two chemicals added to the litter. A total of 64 broiler chicks (4 treatments$\times$4 replicates$\times$4 birds) were fed the experimental diets for 6 weeks. There was no difference in pH between the two chemical treatments and control group, but SRP content was significantly affected on it (P<0.01). SRP contents from ferrous sulfate and alum treated litter at 6 weeks were reduced by $79\%$ and $60\%$, respectively, as the two chemical treatments decreased the pH compared to the control group. In the ferrous sulfate treated litter, EC, TC, $NH_4-N$, $NO_3$-N, and IN contents did not show any difference between $FeSO_4$ treatment and control. However, the differences between $FeSO_4$ treatment and control were found in moisture, TN, ON, AN, PAN, C:N, and C:ON contents (P<0.01). As seen in the alum treated litter, there were differences in moisture, TC, TN, $NH_4-N$, IN, AN, PAN, and C:N contents between alum treatment and control (P<0.05 and 0.01) but no differences in EC, $NO_3-N$, ON, and C:ON. In conclusion, the results of this research show that ferrous sulfate and alum-treatment of poultry litter has the potential to increase N and reduce SRP content by lowering litter pH and moisture content.

• Journal of Music and Human Behavior
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• v.19 no.1
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• pp.21-41
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• 2022

The purpose of this research was to develop and verify applicability of a musical play program aimed at promoting interaction between immigrant preschoolers and Korean preschoolers. A daycare center serving the preschool-age children of Korean nationals and immigrant families were the site for this research. Utilizing the elements of a musical play (e.g., role playing, narration, and joint music activity), the program was developed for improving interaction among preschoolers, while promoting intercultural acceptance by providing the opportunity to be exposed to music from different cultures and engage in the joint activity using such music. For the purpose of investigate the applicability of the developed program, the program was implemented with two groups of preschoolers and each group received the musical play program for 30 minutes twice a week for a total of 6 sessions. The results of this preliminary study indicate that the musical play program promoted interaction between peers from different cultural background. Based on the results of this study, musical play programs may be helpful in promoting interactions between preschoolers from different cultural backgrounds and increase of acceptance of immigrant students in Korean daycares and schools.

• Electric Engineers Magazine
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• v.196 no.12
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• pp.14-20
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• 1998

병원 전기설비는 일반 업무용 건축물과는 달리 순간 정전도 허용하지 않는 대형컴퓨터, 의료용 전기기기, 사무자동화기기 등을 사용하고 있어 특히 전원설비의 고신뢰성, 안전성이 요구되는 비, 본지에서는 병원 전기설비의 안전기준을 살펴보고 조사대사 병원의 수변전설비 구성 현황, 변전시설밀도, 수용률, 최대수요전력의 발생 실태를 검토하고자 한다.

• Analytical Science and Technology
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• v.12 no.1
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• pp.13-21
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• 1999

Silicate used as laundry detergent builder was good for pH buffering capacity and solubility but calcium-ion binding capacity and surfactant adsorption ability were lower. As $SiO_2/Na_2O$ molar ratio became higher, pH buffering capacity and ion exchange ability were lower and surfactant adsorption ability was little higher. Anionic surfactant LAS (linear alkylbenzene sulphonate), nonionic surfactant LA-9 (lauryl alcohol EO-9) were used to investigate the detergency performance. Zeolite was better than sodium silicate in detergency performance. In case of LAS, detergency performance was good when $SiO_2/Na_2O$ molar ratio was lower. In case of LA-9, detergency performance was similar without discrimination of molar ratio of $SiO_2/Na_2O$.

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.3
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• pp.163-172
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• 2006

Pot experiments were conducted from 1999 to 2001 to compare the different methods of available phosphorus (P) for estimation of biomass and P uptake by tomato and cucumber grown on different soils (25 soils for tomato and 8 soils for cucumber cultivation) collected from plastic film house of Chungbuk area. Supplementary experiment was conducted to estimate the relationship among several extraction methods of available P such as P adsorption, water extractable-P, Lancaster-P, Olsen-P, Bray No 1 and No 2-P, and Mehlich 1 and 3-P for a total of 71 soils that included 33 soils collected for tomato and cucumber cultivation and 38 soils taken from other sites of plastic film house. All the extraction methods of available phosphorus except P adsorption were mutually positive correlated with r ranging from 0.81 to 0.96 while the correlation coefficient between P adsorption and other methods ranged from -0.57 to -0.80. Phosphorus uptake by tomato plant applied with no fertilizer was significantly correlated with the available P extracted by different methods except P adsorption in all the experiments showing positive correlation coefficients from 0.49 to 0.76 in April, 1999, 0.53 to 0.71 in April, 2000, and 0.59 to 0.68 in October, 2000. Consequently relative amount of P uptake by tomato plant for all the experiments also significantly correlated with available P in soils showing correlation coefficients of r=0.64~0.73 (P<0.0000001) in the order of Mehlich 1-P > Mehlich 3-P > Lancaster-P. For tomato, critical concentrations of available P in soils estimated by Cate and Nelson split method were $1700mg\;kg^{-1}$ for Mehlich 3-P, $1,050mg\;kg^{-1}$ for Mehlich 1-P, and $95mg\;kg^{-1}$ for water extractable P. Also P uptake by cucumber plant was significantly correlated with Olsen-P, water extractable P, and Bray No 2-P with r value of 0.62, 0.59, and 0.51, respectively, in soils of no fertilization.