HID LAMP 驅動을 위한 類似共振形 INVERTER에 관한 硏究

金光一,裵相俊 慶一大學校 1992 論文集 Vol.8 No.1

The cricuit of QRI(Quasi-Resonant Inverter) which is able to regulate frequency in the output voltage by the ZVS(Zero Volt Switching) was investigated. We found parameters in the circuit of QRI so that they have application to the HID(High Intensity Discharge) Lamp drive. Then we simulated that by personal computer and summarized the result of simulation.

經濟法序說

朴光緖 中央大學校 法政大學 學生會 1965 法政論叢 Vol.11 No.1

Corynebacterium hofmannii에 依한 전신감염 1예

문대혁,최강원,박석건,이광호 대한감염학회 1984 감염 Vol.16 No.1

Corynebacterium of hoffmannii is a part of normal pharyngeal flora. Human infection caused by C. hofmannii is very rare. All reported cases involve prosthetic or native cardiac valve. This patient sufered from chronic alcohlism, diabetes mellitus, and acute suppurative inflammation of brain, meninges and soft tissue. And he failed to show any clinical response to various antimicrobial therapy and died after discharge.

초등교원양성대학의 교육서비스품질과 학생만족도 및 충성도의 구조적 관계

곽민석(Kwag Min Seok),곽현규(Kwag Hyun Gyu) 학습자중심교과교육학회 2017 학습자중심교과교육연구 Vol.17 No.18

본 연구는 초등교원양성대학의 교육서비스품질과 학생만족도 및 충성도의 구조적관계를 분석하는데 그 목적이 있다. 모집단으로는 현재 전국교육대학교에 재학 중인 학생들을 선정하였고, 이 중 서울과 강원도, 충청도에 소재한 A대학교, B대학교, C 대학교 학생들을 2017년 6월 5일부터 23일까지 약 3주간 표본 집단으로 설정하여 연구를 진행하였다. 연구의 수행을 위해 설문지를 측정도구로써 사용하였으며, 총 234명의 자료를 분석하여 가설을 검증하였다. 자료 처리에는 Windows용 PASW 18.0과 AMOS 20.0 프로그램을 이용하였으며, 빈도분석, 신뢰도 분석, 확인적 요인분석, 상관관계분석, 구조방정식 모형분석을 통해 자료를 분석하였다. 본 연구의 결과는 다음과 같다. 첫째, 교육서비스품질은 학생만족도에 긍정적인 영향을 미치는 것으로 나타났다. 둘째, 교육서비스품질은 학생충성도에 영향을 미치지 않는 것으로 나타났다. 셋째, 학생만족도는 학생충성도에 긍정적인 영향을 미치는 것으로 나타났다. 마지막으로 교육서비스품질과 학생충성도 사이에서 학생만족도는 매개하는 것으로 나타났다. The current study was aimed to investigate the structural relationships among educational service quality, satisfaction, and loyalty. Data were drawn from 234 students in three different universities. PASW 18.0 for windows and AMOS 20.0 program were used for data processing. Data were analyzed using frequency analysis, reliability analysis, confirmatory factor analysis, correlation analysis, and structural equation modeling techniques. The results were as follows. First, educational service quality had a positive effect on satisfaction. Second, educational service quality did not affect loyalty. Third, satisfaction had a positive effect on loyalty. Lastly, satisfaction fully mediated the relationship between educational service quality and loyalty.

Beneficial and Detrimental Effects of Soil-Structure Interaction on Probabilistic Seismic Hazard and Risk of Nuclear Power Plant

Kwag, Shinyoung,Ju, BuSeog,Jung, Wooyoung Hindawi Limited 2018 Advances in civil engineering Vol.2018 No.-

<P>The purpose of this study is to investigate the soil-structure interaction (SSI) effect on the overall risk of a PWR containment building structure with respect to two failure modes: strength and displacement. The precise quantification of the risk within the seismic probabilistic risk assessment framework depends considerably on an accurate treatment of the seismic response analysis. The SSI effect is one of the critical factors to consider when accurately predicting structural responses in the event of an earthquake. Previous studies have been conducted by focusing more on the positive side of the SSI effects and the effects mainly on the seismic fragility result. Therefore, this paper presents the results of a study of the SSI effect on the overall risk. Also, the study relies on an emphasis on revealing a beneficial and a detrimental effect of the SSI by utilizing an example of the containment structure in three soil conditions and two main failure modes. As a result, the consideration of SSI shows a complete conflicting effect on the seismic fragility and risk results depending on two failure modes considered in this study. This has a positive effect regarding the strength failure mode, but this brings a negative effect regarding the displacement failure mode. The risk fluctuation width is particularly noticeable in the site having a considerable change in seismic hazard information such as Los Angeles on the western site of the US. Such results can be expected to be utilized in a future study for investigating the pros and cons of the SSI effect associated with various failure modes in diverse conditions.</P>

Who’s the king of the world?

Kwag, Hyo Jung 한국콘텐츠학회 2022 ICCC International Digital Design Invitation Exhib Vol.2022 No.07

Facile synthesis of partially uncapped liposomes

Kwag, Dong Sup,Park, Kyeongsoon,Youn, Yu Seok,Lee, Eun Seong Elsevier 2015 Colloids and surfaces. B, Biointerfaces Vol.135 No.-

<P><B>Abstract</B></P> <P>Sophisticated control of the assembly of nano-sized structures to achieve desired properties is one of the most efficient techniques in drug carrier design. In this study, we hypothesized that under magnetic shear stress, high-density superparamagnetic Fe<SUB>3</SUB>O<SUB>4</SUB> nanoparticles dispersed in a liposome would apply a high load in a particular direction to a liposome membrane and ultimately generate open lipid bilayer holes. Indeed, the designed experimental conditions enabled the formation of one or multiple open pore sites in liposome membranes. With this evidence, open lipid bilayer holes in liposome membranes were further used as open entrances for proteins (bovine serum albumin or insulin) into the liposomes prior to the natural recovery (<I>i.e.</I>, closing) of the lipid bilayer holes. This trial will provide potential opportunities for the engineering of functional liposomes for protein drug delivery.</P> <P><B>Highlights</B></P> <P> <UL> <LI> We developed a new fabrication method for partially uncapped liposomes using Fe<SUB>3</SUB>O<SUB>4</SUB> nanoparticles. </LI> <LI> Under magnetic shear stress, Fe<SUB>3</SUB>O<SUB>4</SUB> nanoparticles dispersed in a liposome ultimately generated open lipid bilayer holes. </LI> <LI> This method is simple and safe for biomedical and cosmetic application. </LI> </UL> </P>

Hyaluronated fullerenes with photoluminescent and antitumoral activity

Kwag, Dong Sup,Park, Kyeongsoon,Oh, Kyung Taek,Lee, Eun Seong The Royal Society of Chemistry 2013 Chemical communications Vol.49 No.3

<P>Hyaluronated fullerene has strong near-infrared (NIR) fluorescence intensity without labelling with any fluorophores or isotopes. This fullerene allowed high-resolution fluorescent imaging of tumor sites <I>in vivo</I> and resulted in a significant regression of HCT-116 tumors.</P> <P>Graphic Abstract</P><P>Hyaluronated fullerene has strong near-infrared (NIR) fluorescence intensity without labelling with any fluorophores or isotopes. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c2cc36596k'> </P>

Gating of NMDA receptor-mediated hippocampal spike timing-dependent potentiation by mGluR5

Kwag, Jeehyun,Paulsen, Ole Pergamon Press 2012 NEUROPHARMACOLOGY - Vol.63 No.4

<P>Hippocampal long-term potentiation (LTP) is believed to be important for learning and memory. Experimentally, the pairing of precisely timed pre- and postsynaptic spikes within a time window of ∼10 ms can induce timing-dependent LTP (tLTP), but the requirements for induction of tLTP change with development: in young rodents single postsynaptic spikes are sufficient to induce tLTP, whereas postsynaptic burst firing appears to be required in the adult. However, hippocampal neurons <I>in vivo</I> show theta-modulated single spike activities also in older hippocampus. Here we investigated the conditions for single spike pairing to induce tLTP at older CA3–CA1 synapses. We found that the pairing of single pre- and postsynaptic spikes could induce tLTP in older hippocampus when the postsynaptic neuronal membrane was depolarized and the pairing frequency exceeded ∼4 Hz. The spike frequency requirement is postsynaptic, as tLTP could still be induced with presynaptic stimulation at 1 Hz as long as the postsynaptic spike frequency exceeded ∼4 Hz, suggesting that postsynaptic theta-frequency activity is required for the successful induction of tLTP at older CA3–CA1 synapses. The induction of tLTP was blocked by an NMDA receptor antagonist and by the selective mGluR5 blockers, MPEP and MTEP, whereas activation of mGluR1 and mGluR5 by DHPG relieved the postsynaptic spike frequency requirement for tLTP induction. These results suggest that activation of mGluR5 during single-spike pairing at older CA3–CA1 synapses gates NMDA receptor-dependent tLTP.</P>

The Relation between Electrical Resistivity and the Microstructure in the Al-Mn Alloys

Kwag, Young Jik 수원대학교 기초과학연구소 1997 基礎科學論文集 Vol.6 No.-

합금의 미세구조를 결정짓는 중요한 세 가지 요소는 고용체 속에 들어 있는 고용체 원소의 밀도, 석출물의 크기와 량, 그리고 각종 격자 결함이다. 연구에 사용된 알루미늄 망간 합금 속에는 1.25%의 망간이 들어 있는데 이 망간은 열처리 온도와 시간에 따라 고용체 속에 녹아 있기도 하고, 석출물로 석출하기도 한다. 열처리 온도와 시간을 이용하면 석출하는 알루미늄망간(Al_6Mn)상의 크기와 밀도를 조절할 수 있다. 1.27㎝ 두께로 스트립 캐스팅된 상태로 입수한 시료는 적당한 크기로 잘라 세 가지 다른 온도에서 2시간 열처리 한 후에 전기전도도와 강도를 측정하고 전자현미경(TEM)으로 미세구조를 측정하였다. 이 시료들은 다시 냉간 압연하여 격자 결함을 증가시킨 후 서로 다른 온도에서 열처리하여 전기전도도와 미세구조를 조사하였다. 이 실험의 결과 금속의 비저항은 고용체 속에 들어 있는 망간 원소의 량에 의해 결정되고 석출입자의 크기나 량, 그리고 격자결함에는 큰 영향을 받지 않는 것으로 나타났다.