Group A-beta Hemolytic Streptococci에 의한 소아 인두편도염에 있어서 Cefprozil의 항균력과 임상적 및 세균학적 효과에 관한 연구

김민우,안영민,장성희,마상혁,안병문,김종덕,이종국,김미란,장진근,박진영,배종우,차성호,Kim, Min-Woo,Ahn, Young-Min,Jang, Seong-Hee,Ma, Sang-Hyuk,Ahn, Byung-Moon,Kim, Jong-Duk,Lee, Jong-Kook,Kim, Mi-Lan,Chang, Jin-Kun,Park, Jin-Young,Bae, J 대한소아감염학회 2001 Pediatric Infection and Vaccine Vol.8 No.2

최근 소아의 인두염 및 인두편도염에서 EM-resistant group A streptococci가 15~40%까지 보고가 되고 있으며, 같은 계통의 macrolide제제들의 대한 내성도 점차 증가하고 있는 양상이 나타나고 있다. 따라서 세균성 인두편도염이 의심되는 환아의 치료에 있어서 경구용 항생제를 선택할 때는 항생제에 대한 내성과 경제성 및 환아의 순응도를 고려하여 항생제를 선택하여야 하겠다. Objective : To determine the clinical and bacteriologic efficacy and safety of Cefprozil in acute pharyngitis and pharyngotonsilitis caused by Group A beta hemolytic streptococci in pediatric patients. Methods : Any patient of 3 to 14 age who visited the hospitals enrolled in this study with the signs and symptoms of pharyngitis or pharyngotonsilitis since July, 2000 to March, 2001, was taken throat culture and given Cefprozil(15 mg/kg/day, in two divided doses) for 10 days. 138 patients of whom showed positive culture results were followed up for the signs and symptoms during the treatment to determine clinical efficacy. Any undesirable effect was reported to determine the safety of the drug. Follow up cultures were done at the end of the study and bacteriologic efficacy was determined. Results : 138 of 256 patients who visited the hospitals with the signs and symptoms of pharyngitis or pharyngotonsilitis showed positive growth on throat culture. Mean age of the patients was $6.1{\pm}2.5$ and males and females were equally numbered. 129 of them complained fever on the first visit and 112(86.6%) of them were improved at the end of the study. Cervical lymphadenitis was seen in 58 patients and 44(75.9%) of them improved at the end of the study. Exudative pharyngitis was seen in 96 patients and 81(84.3%) of them improved. The overall clinical effcacy based on this results showed that 110(79.7%) of the patients were cured and 17(12.3%) of them improved. On the cultures and bacteriologic efficacy, 24.6% of them showed documented eradication after treatment and 62.3% of them showed presumptive eradication. Sensitivity test was done by agar dilution method and Cefprozil showed 100% sensitivity. Erythromycin, Clarithromycin and azithromycin showed 87%, 85.6 %, 90.6% sensitivity, respectively. Conclusion : Cefprozil is proved to be effective in controlling group A streptococcal pharyngitis and pharyngotonsilitis in children and showed good sensitivity. Cefprozil can be used as an effective oral cephalosporin in the patients showing penicillin hypersensitivity or patients who other drugs have failed.

YBCO 초전도 박막 선재용 Ni-W 및 Ni-W-Cu 합금의 격자상수 변화

김민우,정규동,전병혁,김형섭,김찬중,Kim Min-Woo,Jung Kyu-Dong,Jun Byung-Hyuk,Kim Hyoung-Seop,Kim Chan-Joong 한국초전도학회 2005 Progress in superconductivity Vol.7 No.1

We fabricated Ni-based alloy substrates for YBCO coated conductor using powder metallurgy. Tungsten and copper were selected as alloy elements due to their mutual solubility to the base element of nickel. The alloying elements were mixed with nickel using ball milling and dried in air. The powder mixtures were packed in a rubber mold, cold isostatic pressed 200 MPa and made into rods. The compacted rods were sintered at $1150^{\circ}C$ for 6 hours for densification. It was confirmed by neutron diffraction experiment that W and Cu atoms made complete solid solution with Ni. Lattice constant of nickel alloy increased by $0.004{\AA}$ for 1at. $\%$ W in Ni-W alloy, $0.0006{\AA}$ for 1 at. $\%$ Cu in Ni-W-Cu alloy.

흉통을 주소로 응급실에 내원한 환자에서 심전도 촬영 소요 시간에 대한 응급벨 제도의 효과

김민우,오상훈,박규남,이정민,이영미,김한준,김수현,강동재,Kim, Min-Woo,Oh, Sang-Hoon,Park, Kyu-Nam,Lee, Jung-Min,Lee, Young-Mee,Kim, Han-Joon,Kim, Soo-Hyun,Kang, Dong-Jae 한국의료질향상학회 2014 한국의료질향상학회지 Vol.20 No.1

Objectives: The aim of this study was to explore whether emergency bell could shorten door to electrocardiograms (ECG) time in chest pain patients presenting to emergency department (ED) by self-transport. Methods: This was a planned 6-month before-and-after interventional study design. We set up the emergency bell in walk-in patients' waiting room. Prior to the change, patients were triaged before an ECG was obtained. In new process, as soon as patient with chest pain push the emergency bell, emergency physicians examined patient and prioritized performing ECG. We analyzed door to electrocardiograms (DTE) times for patients with chest pain and ST segment elevation myocardial infarction (STEMI) patients between two periods. Results: During the enrollment period, a total of 63 patients called emergency bell. The median DTE time was 6 min (interquartile range: 3.0 - 9.0) and 82.5% received an ECG within 10 minutes, and only three patients were STEMI. DTE time in patient with chest pain was not different between two periods (p=0.980). Before intervention period, 15 walk-in patients admitted in ED for STEMI and 53.8% of STEMI patients received an ECG within 10 minutes. After intervention period, total 19 walk-in patients admitted in ED for STEMI. Of these, 89.5% met the time requirement. Conclusion: Because a small portion of patients with chest pain activated the emergency bell, new strategy for promotion of emergency bell must be needed.

분말 모합금 빌렛으로부터 제조된 Ni-W 합금테이프의 기계적 성질과 집합도

김민우,전병혁,지봉기,정규동,김찬중,Kim, Min-Woo,Jun, Byung-Hyuk,Ji, Bong-Ki,Jung, Kyu-Dong,Kim, Chan-Joong 한국분말야금학회 2007 한국분말재료학회지 (KPMI) Vol.14 No.1

The mother Ni-W (1-5 wt.%) alloy billets for coated conductor substrate were fabricated by powder metallurgy process. The tensile test results for the sintered Ni-W rods showed the increase of mechanical strength and decrease of ductility with increasing W content due to the solid solution hardening. All the fracture surfaces of the tested specimens showed the typical ductile fracture mode of dimple rupture due to the local necking. The Ni-W alloy billets were made into tape by cold rolling. After the appropriate heat treatment for recrystallization, the brass texture formed by the cold rolling was converted to the complete cube texture. The in-plane and out of plane texture of the tapes estimated by x-ray pole figure were smaller than 9 degree and 7 degree, respectively. The effect of the W addition on the texture development seems not to be significant.

과메기에서 histamine 분해능을 나타내는 세균의 분리 동정

김민우,김영만,Kim Min-Woo,Kim Young-Man 한국생명과학회 2006 생명과학회지 Vol.16 No.1

To isolate and identify histamine degrading bacteria from Kwamegi, bacteria were screened with restriction media containing histamine. Ten strains were selected through morphological and biochemical identification procedure followed by comparison with DNA sequence of 16 rRNA gene. And also, these strains were confirmed by the histamine degrading assay such as turbidity and enzymatic assay. The results of identification are as followings : Ewingella americana B791, Arthrobacter sp. R45S, Halomonas marisflava, Psychrobacter sp. 9B-7, Bacillus sp. LMC 21002, Psychrohacter cibarius BC-220, Bacillus megaterium KL-197 were identified showing homology of $99\%,\;95\%,\;98\%,\;99\%,\;99\%,\;99\%\;and\;98\%$, respectively. Three strains remain unidentified. Arthrobacter sp. R45S, H. marisflava, Bacillus sp. LMG 21002, B. megaterium KL-197 showed histamine degrading activity, whereas, Psychrobacter sp. 9B-7 only showed weak activity. Three unidentified strains also have histamine degrading activity. In contrast, E. american B791 and p. cibarius JG-220 did not show any significant activity of histamine degradation. The strains isolated from this study showed relatively fast growth rate and histamine degrading rate as compared to those from salted mackerel. 과메기에서 histamine분해능을 가진 세균을 분리 동정하기 위하여 histamine만을 첨가한 제한배지에서 균을 분리했다. 기본적인 형태 및 생화학적 동정시험을 거쳐 10종의 시험균주를 선택하여 16S rDNA 염기서열 비교에 의한 계통발생학적 분석으로 동정하였다. 동정된 세균의 histamine분해능은 탁도측정법과 효소법에 의해 재 확인하였으며 그 실험 결과는 다음과 같다. 16S rDNA 염기서열 비교에 의한 계통 발생학적 분석을 이용하여 동정한 결과, E americana B791, Arthrobacter sp. R45S, H. marisflava, P. sp. 9B-7, Bacillus sp. LMG 21002, P. cibarius JG-220, B. megaterium KL-197 7종이 동정되었고, 각각 $99\%,\;95\%,\;98\%,\;99\%,\;99\%,\;99\%,\;98\%$의 상동성을 보였으며, 3종은 미동정되었다. 동정된 세균의 histamine분해능을 탁도측정법과 효소법에 의해 재 확인한 결과, Arthrobacter sp. R45S, H. marisflava, Bacillus sp. LMG 21002, B. megaterium KL-197이 분해능을 나타내었고, Psychrobacter sp. 9B-7은 미약한 분해능을 보였으며 미동정된 3종도 분해능이 있는 것으로 나타났다. 그리고 E. americana B791과 P. cibarius JG-220은 분해능이 불확실한 것으로 확인되었다 자반고등어에서 분리한 균주보다 시험균주 모두가 생육과 histamine의 분해속도가 비교적 빨랐다.

2-Aminoindan 및 cis- ( ${\pm}$ ) -4,4a,5,9b-tetrahydroindeno[1,2-b][1,4]oxazin-3(2H)-one의 효율적 합성

김민우,마은숙,Kim, Min-Woo,Ma, Eun-Sook 대한약학회 2006 약학회지 Vol.50 No.6

1-Amino-5,6-dimethoxyindan hydrochloride was synthesized from 3- (3,4-dirnethoxyphenyl)propionic acid by intramolecular Friedel-Crafts acylation, oximation with hydroxylamine, and reduction with an overall yield of 74%. 2-Amino-5,6-dimethoxyindan hydrochloride was synthesized from 3-(3,4-dirnethoxyphenyl)propionic acid by intramolecular Friedel-Crafts acylation, oximation with isoamylnitrite, reduction in NaOH and reaction with HCI to form 5,6-dimethoxy-2-indanone, which was reacted with hydroxylamine and reduced with an overall yield of 42%. 5,6-Dimethoxyindan-1,2-dione-2-oxime, which was catalytically hydrogenated to afford cis-, and trans-1-amino-5,6-dimethoxyindan-1-ol as 3 : 1 ratio. This mixture was treated with Li and reacted with chloroacetyl chloride. Cis isomer was acylated and cyclized to synthesize rir -( ${\pm}$ )-7,8-dimethoxy-4,4a,5,9b-tetrahydroindeno[1,2-b][1,4]oxazin-3(2H)-one, but trans isomer was just acylated to form amide.

GPS 주파수간 편이 추정정확도 분석

김민우,김정래,허문범,Kim, Minwoo,Kim, Jeongrae,Heo, Moonbeom 항공우주시스템공학회 2010 항공우주시스템공학회지 Vol.4 No.1

The accuracy and integrity of global navigation satellite systems (GNSS) can be improved by using GNSS augmentation systems. Large ionospheric spatial gradient, during ionosphere storm, is a major threat for using GNSS augmentation systems by increasing the spatial decorrelation between a reference system and users. Ionosphere decorrelation behavior can be analyzed by using dual frequency GPS data. GNSS receivers have their own biases, called inter-frequency bias (IFB) between dual(P1 and P2) frequencies and they must be accurately estimated before computing ionosphere delays. GPS network data in Korea is used to compute each receiver's IFB, and their estimation accuracy and variability are analyzed. IFB estimation methodology to apply for ionosphere gradient analysis is discussed.

더욱 소형화된 와이파이 이중대역용 직사각형 2단 계단식 슬롯 안테나

김민우,이영민,이희재,이영순,Kim, Min-woo,Lee, Yeong-min,Lee, Hee-jae,Lee, Young-soon 한국인터넷방송통신학회 2021 한국인터넷방송통신학회 논문지 Vol.21 No.6

본 논문에서는 와이파이용으로 더욱 소형화된 이중대역 슬롯 안테나를 새롭게 제안하였다. 제안된 안테나는 이중 주파수 대역에서 정재파 공진을 발생시킬 수 있는 개방종단의 직사각형 2단 계단형 슬롯과 L-형 마이크로스트립 급전선으로 구성된다. 측정결과 임피던스 대역폭은 저주파수 대역에서는 58 MHz(2.412 ~ 2.470 GHz) 및 고주파수 대역에서는 452 MHz(5.451 ~ 5.903 GHz)로 각각 측정되었다. 더욱이 제안된 안테나의 크기 14 × 21 mm²는 기존의 유사소형 슬롯 안테나의 크기 20 × 21 mm²에 비해 30% 정도의 크기로 줄어든 결과이다. H-Plane 상에서 무지향성을 가지는 전형적인 다이폴 안테나의 방사패턴 특성을 가지고 있어 Wi-Fi와 같은 상용 무선 네트워크 용도로 사용하기에 매우 적합하다고 판단된다. In the present study, a more compact dual-band slot antenna is newly proposed for Wi-Fi application. The proposed antenna is composed of rectangular two stepped slot with open end which can generate standing wave resonance at dual frequency bands and L-type microstrip feed line. The measured impedance bandwidths are 50 MHz(2.412 ~ 2.470 GHz) at low frequency band and 452 MHz(5.451 ~ 5.903 GHz) at high frequency band respectiviely. Furthermore its size of 14 × 21 mm² is reduced by 30% compared to the size of 20 × 21 mm² of a conventional similar compact slot antenna. It has the omni-directional radiation pattern characteristics of a typical dipole antenna on the H-Plane, so it is suitable for commercial wireless network applications such as Wi-Fi.

고온전기분해시스템의 열교환기 후보재료에 대한 고온증기 환경에서의 부식평가 현황

김민우,김동훈,장창희,윤덕주,Kim, Minu,Kim, Dong Hoon,Jang, Changheui,Yoon, Duk-Joo 한국압력기기공학회 2009 한국압력기기공학회 논문집 Vol.5 No.1

본 논문에서는 국제적으로 개발 중인 초고온가스로와 연계하여 대량의 수소를 생산하기 위한 방안의 일환으로 국내에서 개발 중인 고온증기전기분해 시스템에 사용될 열교환기 재료의 고온증기 부식실험에 대해 소개하였다. 이를 위해 관련된 국내외 연구현황을 조사분석한 결과를 요약하여 소개하였으며 마지막으로 현재 수행중인 고온증기부식 연구의 실험조건 및 계획을 제시하였다. 실험 및 연구결과는 초고온가스로와 연계된 고온전기분해를 이용한 수소생산시스템의 개발에 활용될 예정이다. Nuclear hydrogen production using high temperature heat of a very high temperature reactor(VHTR) is one of the most attractive ways of mass hydrogen production without greenhouse gas emission. In many countries, sulfur-iodine(S-I) thermochemical process and high temperature steam electrolysis(HTSE) process are being investigated. In such processes, corrosion behavior of Intermediate heat exchanger materials are the most critical issues. Especially in a HTSE system, several heat exchangers will be facing hot steam conditions. In this paper, the status of high temperature corrosion researches in hot steam and supercritical water conditions are reviewed in view of the implication to HTSE conditions. Based on the review, test condition and plan of the hot steam corrosion of the candidate materials are formulated and described in some details along with the schematics of the test set-up. The test results and subsequent evaluation will be used in development of a interface system between the HTSE hydrogen production system and the VHTR.

전해액 첨가제를 이용한 고전계 양극산화의 자기정렬에 관한 연구

김민우,박성수,심성주,강태호,신용봉,하윤철,Kim, Min-Woo,Park, Seong-Soo,Sim, Seong-Ju,Kang, Tae-Ho,Shin, Yong-Bong,Ha, Yoon-Cheol 한국전기화학회 2011 한국전기화학회지 Vol.14 No.4

옥살산 수용액에서의 전기화학적 양극산화에 의한 자기정렬된 알루미나 나노템플레이트의 제조에 있어서 전해액 첨가제를 이용하여 기존 양극산화 법으로는 보고된 바 없는 160~200 V 범위의 자기 정렬 구간을 관찰하였다. 고전계 양극산화와 펄스분리법 및 화학적 기공확장을 거쳐 생성된 자기 정렬구조를 FE-SEM 으로 관찰한 결과 이 전압구간에서의 기공간격과 전압과의 관계는 2.2 nm/V 으로 기존 고전계 양극산화의 결과와 유사하게 나타남을 알 수 있었다. 또한 양극산화막의 성장속도는 약 60 ${\mu}m$/hr로 유사한 기공구조를 얻을 수 있는 인산 수용액에서의 연질 양극산화에 비해 약 30배로 높은 것을 알 수 있었다. 이러한 고찰을 통하여 기공간격 300 nm 이상의 나노템플레이트를 고속으로 제조할 수 있는 조건을 확립하였다. Using an electrolyte additive, we examined, for the first time, a novel self-ordering regime of 160~200 V in high-field anodization which had been used for a fast fabrication of self-ordered anodic alumina nanotemplate. FE-SEM analyses conducted after the high-field anodization, pulse detachment and chemical widening of pores showed the relationship of 2.2 nm/V in this voltage range, which was identical to the previously reported one in the literature. The growth rate of the alumina film was about 60 um/hr, which was 30 times faster than that of phosphoric acid mild anodization. This study provides a new process for the fast fabrication of nanotemplates with interpore distances larger than 300 nm.