풍차형 초음파 전동기의 제작과 토크 및 정$\cdot$역회전특성

김영균,김진수,Kim, Young-Gyun,Kim, Jin-Soo 대한전기학회 2001 전기학회논문지C Vol.50 No.3

In this paper, the windmill type ultrasonic motors with 11.35 mm diameter, 2.87 mm thickness of metal endcap and 1.47 g weight were fabricated. Effects of slots and thickness on torque characteristic in the windmill type ultrasonic motor were investigated, when stator's slots were changed from 4, 6, 8 and thickness 0.15 mm, respectively. Specially designed metal endcaps with windmill shaped cutting can provide longitudinal and torsional displacements simultaneously as the ceramic disk vibrates radically. The windmill type ultrasonic motor has only three components: a stator element with windmill shape slotted metal endcap, a rotor and bearing. Ultrasonic motor stimulated to ultrasonic oscillations by piezoelectrics to drive a rotor via friction contact. The ultrasonic motor fabricated here was the windmill type ultrasonic motor operated by single-phase AC source. Bidirectional revolution using single-phase high frequency for driving the ultrasonic motor was presented.

갑상선암으로 진단되어 수술을 시행한 예에서, 하시모토 갑상선염의 동반여부를 진단: 초음파, Positron Emission Tomography/CT, 조영증강 CT, 그리고 갑상선 자가항체 검사의 정확성 비교

김영균,이태현,박동희,남상빈 대한영상의학회 2012 대한영상의학회지 Vol.67 No.6

Purpose: To compare the diagnostic accuracy of ultrasonography (US), F18-fluorodeoxyglucose positron emission tomography/CT (PET/CT), contrast enhanced CT (CECT), serum anti-thyroid antibody for detecting Hashimoto’s thyroiditis in thyroid cancer patients who underwent neck surgery. Materials and Methods: A total of 150 patients with suspicious for thyroid cancer, who had previously undergone US guided needle aspiration of thyroid, were evaluated with the use of US, PET/CT, CECT and serum anti-thyroid antibody. The four studies were performed within two months before neck surgery. Hashimoto’s thyroiditis was confirmed by histopathological results. The diagnostic accuracy of US, PET/CT, CECT and serum anti-thyroid antibody were calculated statistically. Results: Hashimoto’s thyroiditis was diagnosed in 51 out of the 150 patients, following neck surgery. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of US were 76.5%, 92.9%, 84.8%, 88.5%, and 87.3%, respectively. The corresponding values of PET/CT were 37.3%, 96.0%, 82.6%, 74.8%, and 76.0%, and CECT were 62.7%, 89.9%, 76.2%, 82.4%, and 80.7%, and serum anti-thyroid antibody level were 90.2%, 93.9%, 88.5%, 94.9%, and 92.7%, respectively. McNemar test revealed significant difference among PET/CT and others, but no significant differences among US, CECT and serum anti-thyroid antibody. Overall, serum anti-thyroid antibody showed most accurate diagnostic performance. Conclusion: In detecting Hashimoto’s thyroiditis, serum anti-thyroid antibody showed higher diagnostic accuracy than others. US also showed relatively high diagnostic accuracy. 목적: 갑상선암으로 진단되어 수술을 시행한 예에서, 하시모토 갑상선염의 동반여부를 진단하는 데 초음파 검사, F18-fluorodeoxyglucose positron emission tomography/CT (PET/CT), contrast enhanced CT (CECT), 갑상선 자가항체 검사의 진단적 정확성을 비교하고자 한다. 대상과 방법: 초음파 유도 미세침흡인생검에서 갑상선암이 확진 또는 의심되어 갑상선의 초음파 검사와 함께 PET/CT, CECT 및 갑상선 자가항체 검사를 시행 후, 2개월 이내에 수술한 150명의 환자를 후향적으로 분석하였다. 하시모토 갑상선염은 수술 후 조직병리학적으로 확진되었으며 각 검사 방법의 진단적 정확성을 비교하였다. 결과: 150명의 환자 중 51명이 수술을 통해 하시모토 갑상선염으로 진단되었다. 하시모토 갑상선염을 진단하는 데 초음파의 민감도, 특이도, 양성예측도, 음성예측도, 그리고 정확도는 76.5%, 92.9%, 84.8%, 88.5%, 87.3%였으며 PET/CT는 37.3%, 96.0%, 82.6%, 74.8%, 76.0%, CECT는 62.7%, 89.9%, 76.2%, 82.4%, 80.7%, 갑상선 자가항체 검사는 90.2%, 93.9%, 88.5%, 94.9%, 92.7%였다. 각각의 진단적 정확성을 비교한 결과 PET/CT가 다른 세 검사법과 통계적으로 유의한 차이를 보였고, 나머지 세 검사법은 갑상선 자가항체 검사, 초음파 검사, CECT 순서로 높은 진단적 정확성을 보였지만 통계적으로 유의한 차이는 없었다. 결론: 하시모토 갑상선염을 진단하는 데 가장 정확한 검사법은 갑상선 자가항체 검사로 92.7%의 정확도를 보였으며, 초음파 또한 정확도 87.3%의 비교적 높은 정확도을 보였다.

Growth dynamics of the seagrass, Zostera marina in Jindong Bay on the southern coast of Korea

김영균,김종협,김승현,김재우,박상률,이근섭 한국조류학회I 2012 ALGAE Vol.27 No.3

Growth dynamics of the seagrass, Zostera marina were examined at the two stations (Myungju and Dagu) in Jindong Bay on the southern coast of Korea. Eelgrass leaf productivities, underwater irradiance, water temperature, dissolved inorganic nitrogen (DIN) in water column and sediments, and tissue carbon (C) and nitrogen (N) content were monitored monthly from March 2002 to January 2004. Underwater irradiance fluctuated highly without a clear seasonal trend,whereas water temperature showed a distinct seasonal trend at both study stations. Water column DIN concentrations were usually less than 5 μM at both study sites. Sediment pore water NH4+ and NO3- + NO2- concentrations were higher at the Myungju site than at the Dagu site. Eelgrass leaf productivity at both study sites exhibited a distinct seasonality,increasing during spring and decreasing during summer. Seasonal variation of eelgrass productivity was not consistent with seasonal patterns of underwater irradiance, or water temperature. Eelgrass tissue C and N content at both study sites also showed significant seasonal variations. Relationships between tissue C and N content and leaf productivities exhibited usually negative correlations at both study sites. These negative correlations implied that the growth of Z. marina at the study sites was probably limited by C and N supplies during the high growth periods.

Effect of Pre-Precipitation on Microstructure and Mechanical Properties of Extruded Mg-Sn-Zn Alloys

김영균,조태희,정석훤,김원태,김도향 대한금속·재료학회 2015 METALS AND MATERIALS International Vol.21 No.4

Effect of pre-precipitation on the microstructure and mechanical properties of extruded Mg-1.1Sn-2Zn alloy (at%) has been investigated in this study. The result shows that the presence of a high density of precipitates before extrusion is very effective in obtaining a fine dynamic recrystallized grain structure. The extrusion of the alloy without precipitates results in a bimodal grain structure with fine grains: ~5 μm-size fine grains and ~15 μm-size coarse grains. On the contrary, the extrusion of the alloy with a high density of precipitates results in a ~2 μm-sized, fully dynamic recrystallized grain structure exhibiting a better combination of mechanical properties. The fine precipitates sheared during extrusion act as nucleation sites for DRX and prevent grain growth because of the pinning effect. This study shows that the aging treatment before extrusion is very effective in obtaining a homogeneous and fine grain structure exhibiting a better combination of mechanical properties.

[2010 신춘단막극제 공연평] 인간, 그 수수께끼를 풀기 위한 고단한 여정

김영균 공연과이론을위한모임 2010 공연과 이론 Vol.- No.37

[발제] 한국적 소극의 소재 발굴과 형식의 탐구 : 극단 76의 ‘수인담 외 4편’, 극단 앙상블의 ‘정씨여자’

김영균 공연과이론을위한모임 2006 공연과 이론 Vol.- No.24

망막분지정맥폐쇄와 관련된 황반부종에서 베바시주맙 안내주입술의 조기치료와 지연치료

김영균,김응석,김무상,유승영,곽형우 대한안과학회 2009 대한안과학회지 Vol.50 No.10

Purpose: To compare the effects of early and late intravitreal injection of bevacizumab in patients with macular edema (ME) due to branch retinal vein occlusion (BRVO). Methods: The study sample included 56 eyes of 56 patients who received intravitreal bevacizumab injection for ME due to BRVO and were followed up with at least six months of observation. We retrospectively divided eyes into two classes that included 36 eyes with a disease duration of ≤ 3 months (early treatment group) and 20 eyes with a disease duration of > 3 months (late treatment group). We assessed the effects of injection on the best corrected visual acuity (BCVA), central retinal thickness and IOP at one, three, and six months after treatment. Results: There was no statistically significant differences in terms of sex, age, number of injections, ischemia, pre-injection visual acuity and central retinal thickness between the two treatment groups. Improvements in central retinal thickness were observed in both groups but were not significantly different between the groups. Visual acuity improved in both groups after treatment; the improvement was significantly better in the early treatment group observed three and six months after treatment. IOP did not change after treatment in either group. Conclusions: In cases of ME due to BRVO, early intravitreal bevacizumab injection is more effective than late injection for maintaining and improving visual acuity. 목적: 망막분지정맥폐쇄와 관련된 황반부종에서 bevacizumab 안내주입술의 조기치료와 지연치료의 효과를 비교하고자 하였다. 대상과 방법: 망막분지정맥폐쇄와 관련된 황반부종으로 bevacizumab 안내주입술을 받은 환자 중 6개월 이상 추적관찰이 가능했던 56안 을 대상으로 이환기간이 3개월 이하를 조기치료군(36안), 3개월 초과를 지연치료군(20안)으로 분류하여 후향적으로 관찰하였다. 1, 3, 6개 월 시점에 최대교정시력, 중심황반두께 및 안압의 변화를 비교 분석하였다. 결과: 두 군에서 성별, 나이, 주사횟수, 허혈유무, 술 전 시력 및 술 전 중심황반두께는 통계적 차이를 보이지 않았다. 중심황반두께는 두 군 모두 치료 전에 비해 호전되었지만 두 군 간에 의미 있는 차이는 보이지 않았으며, 시력에서도 두 군 모두 치료 전에 비해 호전되 었지만 치료 3개월, 6개월에는 조기치료군에서 더 의미 있는 시력호전을 보였다. 안압의 변화는 치료 전후와 두 군 간에 차이가 없었다. 결론: 망막분지정맥폐쇄와 관련된 황반부종의 치료로 시행하는 bevacizumab 안내주입술은 조기치료가 지연치료에 비해 시력호전 및 유지에 더 효과적일 것으로 생각된다.

[아시테지 겨울 축제] 아시테지가 변해야 한국 아동ㆍ청소년 연극이 변한다

김영균 공연과이론을위한모임 2011 공연과 이론 Vol.- No.41

캐스케이드 시스템 (Cascade System, 소용량 온열원의 멀티 제어 방식)

김영균,김성진 대한설비공학회 2013 설비저널 Vol.42 No.10

Water Uptakes in Polymer electrolyte Membranes in Fuel Cell

김영균,배영찬 한국고분자학회 2008 한국고분자학회 학술대회 연구논문 초록집 Vol.33 No.1