• 한국정보통신학회논문지
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• 제7권8호
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• pp.1612-1620
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• 2003

본 논문에서는 GaAsFET 전력증폭기를 다중반송 통신시스템에서 적용시키고자 설계한 PA증폭기의 측정된 전달함수를 비선형 모델링 한 결과를 제시하였으며 모델링 한 결과를 가지고 설계한 RF 증폭기의 AM­AM 및 AM­PM 비선형 특성을 추정하였다. 추정된 비선형특성 의하여 다중반송전송시스템에서의 증폭기의 근접채널간섭특성(ACPR), QPSK 및 64­QAM과 같은 디지털 변조 신호에 대하여 성상도에서의 데이터 오차벡터의 크기(EVM) 및 BER 관계를 분석하였다. 본 연구에서 제시한 RF GaAs FET의 비선형 모델링은 OFDM을 이용하는 무선 다중반송전송시스템 설계에 적용할 수 있으며 전력증폭기와 디지털 변조 신호에 따른 비선형 관계를 정확하게 추정할 수 있다.

• 한국주조공학회지
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• 제29권3호
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• pp.144-149
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• 2009

In this study, we investigated optimum condition of cooling plate method to obtain semi-solid AM100A Mg alloy with fine and globular morphology. AM100A Mg alloy were hot extruded at $380^{\circ}C$ extrusion temperature under extrusion ratio of 25 : 1 and ram speed of 2.4 mm/sec. Vickers hardness test, optical microscopy, scanning electron microscopy, and image analyzer were performed to identify the optimum conditions of cooling plate method. Optimum conditions of cooling plate method to fabricate semi-solid AM100A Mg alloy with fine and globular microstructures were achieved at a pouring temperature of $602^{\circ}C$ and the angle of cooling plate of 60 degree.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2019년도 춘계학술대회
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• pp.115-115
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• 2019

Arctium minus (AM), commonly known as lesser burdock, is a dried fruit (seed) of Aructium lappa L. that belong to Asteraceae. It has been used traditionally as herbal medicine because of its anti-inflammatory effects, and it has been applied to treat various diseases like allergies, skin aging, hyperlipidemia and urinary stone. In this study, we investigated the inhibitory effects of AM on the production of pro-inflammatory cytokines in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. Pre-treatment of the RAW 264.7 cells with AM considerably inhibited and reduced production of Nitric Oxide (NO) and pro-inflammatory cytokines, such as interleukin (IL)-6 and tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), and also shows suppression of nuclear factor-kappa B (NF-${\kappa}B$) translocation. In addition, AM treatment considerably reduced phosphorylation of mitogen-activated protein kinase (MAPK) in LPS-stimulated RAW 264.7 cells. Our results indicate that the AM has potential to inhibit inflammation through suppressing production of inflammatory mediators via both the NF-${\kappa}B$ and MAPK signaling pathway. We therefore suggest that AM might be effective therapeutics for the treatment of various inflammatory diseases.

• 한국한의학연구원논문집
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• 제13권2호통권20호
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• pp.83-90
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• 2007

The aim of the study was to analyze recent trends of experimental studies regarding to acupuncture and moxibustion (AM) through reviewing the 492 papers in the PubMed database in order to help researchers from overlapping study on the same theme and to spur them to investigate experimental studies on AM with understanding the current flow of that. For the analysis, we include papers in which abstract was written in English. First, we performed quantitative analysis of the experimental studies using whole of the first filtrated 492 papers. From this analysis, we could obtain the followings: 'Trends of study in the most frequently appeared journals and leading authors in experimental study of AM'. 'The number of papers and name of journals by leading authors in experimental study of AM'. 'Trends of Korean papers in the most frequently appeared journals and Korean leading authors in experimental study of AM", 'Classification of experimental studies related to acupuncture and moxibustion according to intervention methods or individual country' and 'Assortment of experimental studies related to acupuncture and moxibustion in terms of intervention methods on leading countries'. Second, we collected 72 papers considering impact factor of the journal and influential effect of the papers' result for qualitative analysis, and we divided the papers into pain related one or not, because the effect of AM on pain is major subject of AM study. The results showed that experimental studies regarding to AM still has several weakness such as limited usage of acupuncture points and inclined application of electroacupucture even though there are 361 acupuncture points in the human body and various kinds of stimulation methods using traditional needles and moxibustion. Therefore, we suggest that researchers should pay more attention to the study on basic AM research creatively and systematically through strengthening and enhancing the cooperation among colleges, research institutes and hospitals. Moreover, in order to promote the basic research of the AM, it is required that we need cross-disciplinary research as well as international collaboration research.

• 대한환경공학회지
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• 제31권9호
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• pp.775-782
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• 2009

PP-g-AA 부직포의 양이온교환기능성 카르복실기(-COOH)를 DETA를 사용하여 화학적 개질반응을 통해 아민기($-NH_2$)를 도입한 음이온교환성 PP-g-AA-Am 부직포를 합성하였다. PP-g-AA-Am 부직포에 대한 회분식 흡착실험을 통하여 흡착등온, 흡착평형 및 공존이온 영향을 살펴보았다. $PO_4$-P의 흡착거동은 Langmuir 흡착등온식에 일치하였으며 흡착에너지는 10.3 kJ/mol로 $PO_4$-P의 흡착과정을 이온교환 반응으로 설명할 수 있었다. 음이온이 같은 몰농도로 혼합된 용액에서 PP-g-AA-Am 부직포의 이온 경쟁력은 $SO_4\;^{2-}$>$PO_4\;^{3-}$>$NO_3\;^-$>$NO_2\;^-$ 순이었다. 또한 PP-g-AA-Am 부직포는 모든 실험에서 이온교환수지인 PA308보다 $PO_4$-P의 흡착능이 우수한 것으로 나타났다.

• Nuclear Engineering and Technology
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• 제41권3호
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• pp.319-326
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• 2009

This study was carried out to investigate the high-acidity co-separation of Am and RE from a simulated radwaste solution by a solvent extraction using a mixture of Dimethyldibutyltetradecylmalonamide (DMDBTDMA, as an extractant) and dihexyl octanamide (DHOA, as a phase modifier) diluted with n-dodecane (NDD). All the experiments were conducted as a batch type. First, the environmentally friendly DMDBTDMA and DHOA composed of only CHON atoms were self-synthesized. Then, the conditions for the prevention of a third phase, generated in the organic phase were examined. In addition, the effects of the concentration of nitric acid, DHOA, oxalic acid and $H_2O_2$ on the co-extraction of Am and RE were elucidated. Consequently, the optimum condition of (0.5M DMDBTDMA+0.5M DHOA)/NDD-0.3M $C_2H_2O_4-4.5M$ $HNO_3$ and O/A=2 was obtained through experimental work. Under this condition, the extraction yields were found to be about 80% for Am, more than 70% for RE such as La, Eu, Nd, Ce, etc., 3% for Cs and Sr, 69% for Fe and less than 11% for Mo and Ru. For the co-extraction of Am and RE, Fe should be removed in advance or prevented from a co-extraction with Am by controlling the different extraction rates of Am and Fe. About 95% of the Am and RE in the organic phase were stripped using a 0.5M $HNO_3$.

• 대한간호학회지
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• 제53권6호
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• pp.571-583
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• 2023

Purpose: This study used a self-deterministic approach to explore the relationship between emotional intelligence (EI), academic motivation (AM), and achievement among health science students. Methods: A descriptive cross-sectional study was conducted in three cities of Saudi Arabia (Dammam, Riyadh, and Jeddah). A convenience sample of 450 students was incorporated using the multistage cluster sampling technique. The online survey contained three sections: students' basic data and academic achievement level, the modified Schutte self-report inventory, and the Academic Motivation Scale lowercase. Results: This study revealed moderate overall scores for EI (57.1%), AM (55.6%), and grade point average (GPA) (57.6%). The overall EI score, its domains, and GPA had significant positive correlations with overall AM and intrinsic and extrinsic motivation (p < .01). Amotivation had an insignificant correlation with GPA (p < .05), but it was negatively correlated with EI and its domains (p < .01). Multiple regression analysis proved that EI domains predicted 5.0% of GPA variance; emotions appraisal and expression (β = .02, p = .024), regulation (β = .11, p = .032), and utilization (β = .24, p < .01). EI domains also predicted 26.0% of AM variance; emotions appraisal and expression (β = .11, p = .04), regulation (β = .33, p < .01), and utilization (β = .23, p < .01). Moreover, AM predicted 4.0% of the variance in GPA; intrinsic (β = .25, p = .004) and extrinsic (β = .11, p = .022) motivation. AM also predicted 25.0% of the variance in EI: intrinsic (β = .34, p < .01) and extrinsic motivation (β = .26, p = .026). Conclusion: EI and AM have a bidirectional influence on each other, significantly shaping the GPA of health sciences students in Saudi Arabia, where intrinsic motivation has a predominant role. Thus, promoting students' AM and EI is recommended to foster their academic achievement.

• 한국어병학회지
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• 제13권2호
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• pp.111-119
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• 2000

군산내만에서 분리한 미생물총 Vibrio spp.(44균주), Pseudomonas spp.(42균주), Aeromonas spp.(26균주), Moraxella spp.(9균주), Enterobacteria spp.(6균주), Bordetella spp.(3균주), Alkaligenesis spp.(3균주), Staphylococcus spp.(3균주), Flavobacterium spp.(2균주)를 총 123주를 대상으로 Ampicillin(AM), Penicillin-G(PM), Rifampicin(RF), Streptomycin(SM), Oxolinic acid(OA), Nalidixic acid(NA), Oxytetracycline(OT), Amikacin(AK), 및 Enorfloxacin(EF)등의 약제에 대해서 감수성검사를 실시하였다. 공시약제에 대한 감수성균주는 42균주(34.1%)이었으며, 내성균주는 81균주(65.9%)로서 약제 내성율은 AM(54균주/43.9%), PM(47균주/38.2%) 및 RF(35균주/28.4%) 등에는 고빈도의 내성을 보였으며, SM(9균주/7.3%), OA(5균주/4.06%) 및 NA(1균주/0.8%)등에는 저빈도의 내성을 보였다. 그렇지만 OT, AK 및 NF에는 내성을 보이지 않았다. 내성 유형은 총 15유형(1-4제)으로서 이중 단일약제 내성 균주는 모두 35균주(28.4%)로서 AM(20균주/16.3%), PM(10균주/16.3%)및 RF(10균주/8.1%)약제에 내성 출현율이 높았다. 한편, 다제내성은 12유형을 나타내었으며, AM-PM-RF(16균주/13.4%), AM-PM(8균주/6.5%) 및 PM-RF(7균주/5.6%)유형이 비교적 출현빈도가 높았다. 따라서 본 해역은 다양한 약제에 내성을 나타내는 미생물총이 서식하고 있어서 향후 다제내성균이 빠르게 확산 되어 어류질병의 치료에 많은 어려움이 예상된다.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1996년도 춘계학술발표회논문집(3)
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• pp.423-428
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• 1996

The feasibility study on burning Am-241, 243 and Cm-244 nuclides in a conventional PWR (Pressurized Water Reactor) was carried out by using the TRIFON code that was developed by the Institute of Theoretical and Experimental Physics in Russia in 1992. TRIFON code uses updated ABBN Russian nuclear cross section library. The reference reactor is the Korea nuclear power plant unit 8 (YGN 2). The burning effect of Am-241, 243 and Cm-244 nuclides was studied with UO$_2$(3.5 w/o)fuel assembly and MOX (4.44 w/o) fuel assembly. The loaded mass ratio of Am-241, 243 and Cm-244 nuclides was obtained from the mass ratio of Am-241, 243 and Cm-244 nuclides in 10 year cooling spent fuel with average discharge burnup of 33 GWD/MTU. The effective transmutation rates of Am-241, 243 and Cm-244 nuclides in UO$_2$ fuel assembly were found to be higher than those in MOX fuel assembly. The result from TRIFON code was compared to that from CASMO-3/NEM-3D code system. For more reliable calculation of transmutation for MA(Minor Actinides) more sophisticated decay chain scheme of MA should be investigated and nuclear cross section library of MA should be considerably improved.

• 한국통신학회논문지
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• 제22권10호
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• pp.2165-2170
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• 1997

본 논문에서는 CDMA 송신기에서 I/Q 불균형, Quadrature offset, 누설반송파와 같은 선형 왜곡 효과와 전력증폭기에서의 AM-AM, AM-PM 잡음과 같은 비선형 왜곡 효과가 시스템에 미치는 성능에 대하여 분석하였다. 이러한 왜곡효과들이 CDMA 송신기의 성능에 어떠한 영향을 미치는지 알아보기 위하여, 송신부의 특성을 나타내는 중요한 인자인 CDMA 변조지수(Modulation quality)를 왜곡 효과의 함수로 나타내었다. 본 논문의 결과로부터 IS-95 표준에서 요구되는 송신부의 성능을 만족하기 위한 각 왜곡효과들의 한계값을 선정할 수 있으며 이로부터 최적의 성능을 갖는 설계가 가능하다.