• 제목/요약/키워드: Lee Seong-Ah

검색결과 374건 처리시간 0.029초

전력품질개선기능을 갖는 계통 연계형 태양광 발전시스템 (Gird-interactive PV Generation System with Power Quality Control)

  • 이성룡;전칠환;고성훈;조아란
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 제37회 하계학술대회 논문집 B
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    • pp.994-995
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    • 2006
  • This paper presents a grid-connected photovoltaic (PV) system with direct coupled power quality control (PQC) algorithm, which uses an inner current control loop (PRT : polarized ramp time) and outer feedback control loop to improve grid power quality and maximum power point tracking (MPPT) of PV arrays. To reduce the complexity, cost and number of power conversions, which results in higher efficiency, single stage CCVSI (Current Controlled Voltage Source Inverter) is used. The proposed system operation has been divided into two modes (sunny and night). In night mode, the proposed system operates to compensate the reactive power demanded by nonlinear or variation in loads. in sunny mode, the proposed system performs PQC to reduce harmonic current and improve power factor as well as MPPT to supply active power from the PV arrays simultaneously. it is shown that the proposed system improves the system utilization factor to 100% which is generally low for PV system (20%). To verify the proposed system, a comprehensive evaluation with theoretical analysis and simulation results are presented.

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Determination of Stability Constants of the Inclusion Complexes of ${\beta}$-Blockers in Heptakis (2,3-Dimethyl-6-Sulfato)- ${\beta}$-Cyclodextrin

  • Phuong, Nuyen Thi;Lee, Kyung-Ah;Kim, Kyung-Ho;Choi, Jung-Kap;Kim, Jong-Moon;Kang , Jong-Seong
    • Archives of Pharmacal Research
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    • 제27권12호
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    • pp.1290-1294
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    • 2004
  • The ${\beta}$-blockers possess at least one chiral center and the S(-)-enantiomer shows higher affinity for binding to the ${\beta}$-adrenergic receptors than antipode. The stability constants of acebutolol, celiprolol, propranolol and terbutaline in the inclusion complexes with single-isomer heptakis (2,3-dimethyl-6-sulfato)- ${\beta}$-cyclodextrin (HDMS-${\beta}$-CD) were determined by capillary electrophoresis. The approximation and linear double reciprocal methods were adapted with comparable results. Among the ${\beta}$-blockers studied, propranolol had the lowest stability constant but the highest enantioselectivity, indicating that the magnitudes of the stability constants carried little information about enantioseparation. The magnitudes of enantioselectivities between the enantiomer pair were in the order of propranolol > celiprolol > terbutaline > acebutolol.

구강에 발생한 심상성 사마귀의 임상병리학적 특징 (A Clinicopathological Review of Verruca Vulgaris Occurring in the Oral Cavity)

  • 신의정;조영아;강경림;윤혜정;홍성두;이재일;홍삼표
    • 치위생과학회지
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    • 제13권3호
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    • pp.354-357
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    • 2013
  • 심상성 사마귀는 피부에서 매우 흔하게 관찰되는 병소중하나이다. 보통 심상성 사마귀는 인간 유두종 바이러스 중저위험군에 의해서 발생된다. 심상성 사마귀는 구강 점막에서 거의 나타나지 않지만 편평유두종으로 오진될 수 있다. 그러므로 저자들은 구강에서 발생한 심상성 사마귀 8예를 임상 병리학적 특징을 관찰하여 보고하였다.

산림교육 패러다임 분석틀의 개발과 적용 (Development and Application of the Framework for Analyzing Forest Education Paradigms)

  • 이재영;김인호;전정일;정수정;곽정난;송성아;권혜선
    • 한국환경교육학회지:환경교육
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    • 제21권1호
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    • pp.31-44
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    • 2008
  • This study was aimed at developing and providing textbook writers with information and materials required to introduce forest education ideas and paradigm into primary, middle, and high school students, responding to establishment of the new national curriculum. Research methods included interview with school teachers, literature review on forest education and policy, analysis of writings and drawings of elementary school students. As a primary result, the study produced a framework that can be applied to analyze and understand how people think of and put a value on forest, consisting of 1) Resource-Economic Perspective, 2) Environmental-Ecological Perspective, 3) Cultural-Educational Perspective, and 4) Existential-Ethical Perspective. To test its validity, the developed framework was applied to the processes of reorganizing and interpreting the outcomes of teacher interview and writings and drawings of elementary school students. The results of applications showed that current school education mostly focused on ecological-environmental (about 50%) and cultural-educational (about 30%) perspectives on forest. To improve the quality of current forest education in schools, five main directions including integration, balance, interrelatedness, identity, and systematic approaches were suggested.

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하지정맥류 증상 측정을 위한 연구 (A study for the measurement of varicose vein symptom)

  • 권진아;신성윤;이현창
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2018년도 추계학술대회
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    • pp.169-170
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    • 2018
  • 생활 수준 향상과 더불어 건강에 대한 관심도가 많이 증가하고 있다. 현대인의 생활 패턴이 편리하고 다양해짐으로써 상대적으로 움직임은 줄어들고 있다. 이러한 생활 패턴변화는 우리의 건강에도 영향을 미치고 있으며, 이를통해 나타난 건강 이상신호도 다양하고 복잡하게 나타나고 있다. 이에 본 연구에서는 하지정맥류로 인한 이상증상을 측정하기 위한 장치가 필요하며, 이와 같은 장치개발을 위해서 하지정맥류 기초연구자료에 관하여 살펴보고자한다. 이를 통해 향후 장치개발을 위한 기본 연구로 활용하고자 한다.

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도시공간모델을 이용한 3차원 소음지도의 생성 (Generation of 3D Noise Maps using a City Spatial Model)

  • 오소정;김성준;최경아;이임평
    • 한국GIS학회:학술대회논문집
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    • 한국GIS학회 2008년도 공동춘계학술대회
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    • pp.387-390
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    • 2008
  • 소음지도는 공간의 소음값을 3차원적으로 분석하여 GIS 데이터에 소음분석결과값을 RGB 값으로 표현한 것이다. 현재의 GIS는 2차원 데이터이므로 3차원 소음분석결과값을 표현하고 사용자들에게 제공하는 것에 효과적이지 못하다. 따라서 본 연구에서는 소음분석결과값을 보다 효과적으로 사용자들에게 제공하기 위하여 3차원 소음지도를 제작하고자 한다. 3차원 소음지도는 도시공간모델의 지형과 건물을 각각 소음분석결과값을 이용하여 texturing하여 가시화한 후 통합하여 완성한다. 지형의 경우, 지형의 기하학적 가시화완 지형의 texturing의 두 단계를 거쳐 완성하고 건물의 경우, 건물의 기하학적 3차원 가시화와 건물의 texturing의 두 단계를 거쳐 생성한다. 건물과 지형의 texturing의 단계에서 texture file은 소음분석결과값을 RGB코드로 변환하여 jpg파일로 생성한다. 생성된 3차원 소음지도는 영등포구 전체 영역을 대상지로 하였고 web기반의 VRML파일이다. 가시화의 효율성을 고려하여 영등포구 영역을 $200m{\times}200m$로 구역을 설정 607개의 구역으로 나누어 가시화하였다. 도시공간 모델을 이용하여 3차원 소음지도를 제작함으로써 도시공간모델을 이용하는 응용분야에서 3차원 공간분석의 가시화를 위한 방법을 제시할 수 있었다. 이를 통하여 공간 문제들의 결과를 사용자들에게 보다 효율적으로 제공할 수 있을 것이다.

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Biochemical Characterization of a Glycosyltransferase Homolog from an Oral Pathogen Fusobacterium nucleatum as a Human Glycan-Modifying Enzyme

  • Kim, Seong-Hun;Oh, Doo-Byoung;Kwon, Oh-Suk;Jung, Jae-Kap;Lee, Yun-Mi;Ko, Ki-Sung;Ko, Jeong-Heon;Kang, Hyun-Ah
    • Journal of Microbiology and Biotechnology
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    • 제18권5호
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    • pp.859-865
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    • 2008
  • Bacterial glycosyltransferases have drawn growing attention as economical enzymes for oligosaccharide synthesis, with their easy expression and relatively broad substrate specificity. Here, we characterized a glycosyltransferase homolog (Fnu_GT) from a human oral pathogen, Fusobacterium nucleatum. Bioinformatic analysis showed that Fnu_GT belongs to the glycosyltransferases family II. The recombinant Fnu_GT (rFnu_GT) expressed in Escherichia coli displayed the highest glycosylation activity when UDP-galactose (Gal) was used as a donor nucleotide-sugar with heptose or N-acetylglucosamine (GlcNAc) as an acceptor sugar. Interestingly, rFnu_GT transferred the galactose moiety of UDP-Gal to a nonreducing terminal GlcNAc attached to the trimannosyl core glycan, indicating its potential as an enzyme for human-type N-glycan synthesis.

비글개에서 인체 재조합 적혈구 조혈인자, rHu-EPO의 급성독성에 관한 연구 (Acute Toxicity of Recombinant Human Erythropoietin (rHu-EPO) in Beagle Dogs)

  • 조명행;성하정;김형식;곽승준;천선아;임소영;김원배;김병문;안병옥;이병무
    • Toxicological Research
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    • 제12권2호
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    • pp.305-308
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    • 1996
  • The acute toxicity of rHu-EPO, newly developed recombinant erythropoietin, was tested in beagle dogs. rHu-EPO, when administered intravenously at 25, 000 IU/kg, did not cause any death. Also, rHu-EPO did not induce any change of body weight, food intake and clinical signs compared to controls. There were no significant changes in hematological, urine analysis and pathological examination. These results showed that rHu-EPO did not induce any remarkable toxic response and the $LD_50$ was greater than 25, 000 IU/kg in beagle dogs.

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Do depression, anxiety, emotional intelligence, and sleep quality affect diabetes management self-efficacy in Korean women with gestational diabetes in pregnancy?: a descriptive correlational study

  • Lee, Hoon Ah;Jang, Keum Seong
    • 여성건강간호학회지
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    • 제27권4호
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    • pp.358-367
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    • 2021
  • Purpose: This study aimed to identify factors associated with diabetes management self-efficacy in pregnant women with gestational diabetes mellitus (GDM) in Korea. Methods: A total of 173 pregnant women with GDM in Korea were recruited by posting announcements at two Korean online communities focusing on pregnancy and GDM. Participants completed a structured online survey from July to September 2018. Thirteen inappropriate responses were excluded and a total of 160 questionnaires were used in the final analysis. Descriptive statistics were calculated and multiple regression with the enter method was done to identify the associations of depressive mood, anxiety, emotional intelligence, and sleep quality with diabetes management self-efficacy. Results: Respondents reported a moderately depressive mood (mean, 10.36), low to moderate anxiety (mean, 41.65), above-average emotional intelligence (mean, 78.04), moderate sleep quality (mean, 42.01), and above-average diabetes management self-efficacy (mean, 52.29). The major factor associated with diabetes management self-efficacy of pregnant women with GDM was emotional intelligence (β=.51, p<.001). Other factors, in descending order of influence, were sleep quality (β=.22, p<.001) and exercise (β=.18, p=.004). Taken together, the aforementioned factors explained 34.6% (F=39.53, p<.001) of the total variance. Conclusion: The results of this study suggest that to improve the diabetes management self-efficacy of pregnant women with GDM, it is necessary to develop an education program that can also enhance emotional intelligence, sleep quality, and exercise.

Morning Glory Syndrome associated with Autosomal Dominant Alport Syndrome with a Heterozygous COL4A4 Mutation

  • Kim, So Jeong;Lee, Jeong Eun;Kwak, Hyun Duck;Kang, Mi Seon;Yu, Seong Ah;Seo, Go Hun;Oh, Seung Hwan;Chung, Woo Yeong
    • Childhood Kidney Diseases
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    • 제25권2호
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    • pp.128-132
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    • 2021
  • Morning glory syndrome (MGS) is a rare congenital optic disc anomaly with a characteristic fundal finding with severe visual impairment. It may occur in association with various systemic manifestations, even though most of the reported cases were isolated. A 6-year-old male visited the nephrology clinic with a history of microscopic hematuria and at the age of 12 years, he was diagnosed thin glomerular basement membrane nephropathy by kidney biopsy. After the following years, the patient had progressive deterioration of visual acuity, and diagnosed as MGS. Whole Exome Sequencing of this patient and his mother revealed heterozygous COL4A4 mutations [c.81_86del (p.Ile29_Leu30del)]. It is more reasonable to consider MGS seen in this patient as a coincidental finding of autosomal dominant Alport syndrome. To our knowledge, this case represents the first case report of autosomal dominant Alport syndrome associated with MGS.