간 경화도 측정을 위한 3.0T 자기공명 탄성계수 영상의 유용성에 대한 고찰 : 확산계수 영상 및 T2 강조 영상과의 비교

김상우,강충환,김성호,김경수,김순배,Kim, Sang-Woo,Kang, Chung-Hwan,Kim, Sung-Ho,Kim, Kyung-Soo,Kim, Soon-Bae 대한디지털의료영상학회 2012 대한디지털의료영상학회논문지 Vol.14 No.1

The purpose of this study is to evaluate the mutual relations by measuring SNR from T2 weighted image and ADC values on the basis of the stiffness values from liver tissues. This study was conducted that total 37 people(23 of males and 11 of females) were taken the liver MRI examination and average age was $54.5{\pm}12.7$ years old. The equipment was MAGNETOM Skyra 3.0T (SIEMENS, Erlangen, Germany) and 32 channel body-array coil. The examination were conducted with HASTE T2 weighted image by axial plane, Spin-echo EPI (echo planner image) DWI (b-value = 800) and Magnetic resonance elastography. The ROIs (region of interest: 200-300 $mm^2$) were established on the basis of the first axial stiffness image corresponded 95% confidence interval from axial stiffness image and then were measured values. After drawing the grid lines, signals were measured SNR from T2 weighted image and ADC values on the same locations that were analysed other 3 planes respectively. The results were showed correlation (0.057) that were increased to SNR from T2 weighted image by increasing stiffness value that no significant difference statistically p = 0.003. Other results were showed correlations (-0.301) that were decreased to ADC values by increasing stiffness values that no significant difference statistically p = 0.088. In the 3.0T equipment, the results may be error in much the same fashion as the 1.5T from ADC values by evaluation of fibrosis stage. However, Magnetic resonance elastography would be useful method that is used to diagnose exactly liver fibrosis stages in the 3.0T.

RF대역 노이즈 저감용 연자성 필름의 전자기파 차폐효과

김상우,윤용운,김광윤,윤여춘,이경섭,Kim Sang-Woo,Yun Yong-Woon,Kim Gwang-Yoon,Lee Yo-Chun,Lee Kyung-Sup 한국마이크로전자및패키징학회 2004 마이크로전자 및 패키징학회지 Vol.11 No.3

연자성 차폐필름에 대하여 ASTM 방법 및 2-port flanged coaxial line 방법으로 RF (radio-frequency) 영역에서 전자기파 차폐특성을 측정하여 원역장에서의 차폐요인을 정량적으로 분석하였다. 4-13.5 GHz의 고주파 영역에서 연자성 차폐필름의 차폐효과는 반사손실에 의한 효과가 아니라 주로 흡수손실에 의한 차폐효과를 가졌다. We charaterized electromagnetic shielding properties of a soft magnetic film using by a ASTM method and 2-port flanged coaxial line method in a RF range and quantitatively analyzed factors for the shielding effectiveness of the soft magnetic film in far field. The shielding effectiveness of the soft magnetic film was dominantly affected by absorption loss not reflection loss in high frequency range of 4-13.5 GHz.

Hertz 접촉하중하에서의 복수표면균열의 상호간섭

김상우,김석삼,Kim, Sang-Woo,Kim, Seock-Sam 대한기계학회 1996 大韓機械學會論文集A Vol.20 No.10

Analysis model containing two inclined surface cracks on semi-infinite elastic body is established and analyzed on the basis of linear fracture mechanics to examine mutual interference of two surface cracks. Muskhelishvili's complex stress functions are introduced and a set of singular integral equations is obtained for a dislocation density function. The stress intensity factors at crack tip are obtained by using the Gerasoulis'method. When two surface cracks are parallel and have the same length, the values of $K_1$and $\Delta K_11$(variation of $K_11$) for crack 1 and crack 2 decrease by the mutual interference of two surface cracks as the distance between the two surface cracks shortens. The effect of mutual interference is remarkable in high friction coefficient. In case that two surface cracks are parallel, the values of $K_1$and $\Delta K_11$for crack 2 decrease as the length ratio ot crack 2 to crack 1 becomes small. As the crack inclination angle rises, the value of $K_1$ and the mutual interference of $K_1$for crack 2 increase and the value of$\Delta K_11$ for crack 1 becomes smaller than that for crack 2.

동결 전 단계적 노출처리방법이 유리화동결 및 초급속동결-융해 후 생쥐 성숙난자의 생존력에 미치는 영향에 관한 연구

김상우,이재익,김미경,이영아,이규섭,윤만수,Kim, Sang-Woo,Lee, Jae-Ik,Kim, Mi-Kyung,Lee, Young-Ah,Lee, Kyu-Sup,Yoon, Man-Soo 대한생식의학회 2000 Clinical and Experimental Reproductive Medicine Vol.27 No.2

Objective: This study was carried out to compare the effects of the stepwise exposure treatments on the morphological normality, fertilization and blastocyst formation rate of the frozen-thawed mouse mature oocytes by vitrification or ultra-rapid freezing and to use as a fundamental data for the cryopreservation of human oocytes. Materials and Methods: The morphological normality and fertilization rates of the vitrified and ultra-rapid frozen mouse mature oocytes after three-stepwise exposure treatments (1step, 3step and 5step) were observed. After choosing the 3step exposure treatment groups, we observed the morphological normality and fertilization, blastocyst formation rate of the vitrified and ultra-rapid frozen mouse mature oocytes. Results: The morphological normality and fertilization rates of the vitrified mouse mature oocytes after three-stepwise exposure treatments (1step, 3step and 5step) were 75%, 85%, 88% and 58%, 61 %, 54% respectively. There were no significant differences among treatments(p>0.05). The morphological normality and fertilization rate of the control was 92% and 65%. There were no significant differences in fertilization rate among control and treatments (p>0.05). The morphological normality and fertilization rates of the ultra-rapid frozen mouse mature oocytes after three-stepwise exposure treatments (1step, 3step and 5step) were 83%, 83%, 84% and 75%, 63%, 56% respectively. There were no significant differences among treatments (p>0.05). The morphological normality and fertilization rate of the control was 95% and 67%. There were no significant differences among control and treatments (p>0.05). The morphological normality and fertilization rate of the vitrified or ultra-rapid frozen mouse mature oocytes after 3step exposure treatment were 69% and 75%, respectively. The blastocyst formation rate was 60% and 57%. The results did not differ significantly between vitrification and ultra-rapid freezing (p>0.05). Conclusion: As known in the above results, there were no significant differences in the fertilization and blastocyst formation rate of the frozen-thawed mouse mature oocytes by vitrification or ultra-rapid freezing among the control and treatments. It is suggested that vitrification and ultra-rapid freezing method were effective for the cryopreservation of mouse mature oocytes.

뇌졸중(腦卒中) 환자(患者)에서 강압혈(降壓穴) 자침(刺針)과 대추혈(大推穴) 사혈(瀉血)의 강압효과(降壓效果)

김상우,박인범,김철홍,서정철,윤현민,장경전,송춘호,안창범,Kim, Sang-woo,Pak, In-bum,Kim, Cheol-hong,Seo, Jung-chul,Youn, Hyoun-min,Jan, Kyung-jeon,Song, Choon-ho,Ahn, Chang-bum 대한침구의학회 2002 대한침구의학회지 Vol.19 No.5

Objective : The aim of this research was to investigate the depressive effect of acupuncture on Gangap-point and depletion on Taech'u-point in stroke patients. Methods : We measured the blood pressure of the patients who were admitted in the Oriental Medical hopital of Dongeui medical center from 21. Oct. 2001. to 20. Jan. 2002. 19 stroke patients were devided into two groups. 12 patients were treated by acupunctured on Gangap-point. The other 7 patients were treated by depletion on Taech'u-point. The activity of daily living was measured. If systolic blood pressure was over 160 mmHg or diastolic blood pressure was over 90 mmHg, acupunctured on Gangap-point and depletion on Taech'u-point were performed. Then 30minutes and 60minutes later, systolic, diastolic blood pressure and pulse rates were measured Results : After 30 minute treatment. both acupuncture on Gnagap-point and depletion on Taech'u-point significantly depressed the systolic blood pressure. After 60 minute treatment. only depletion on Taech'u-point were statistically significant in depressing the systolic blood pressure. Pulse rates were not significantly changed. Conclusion : These results suggest that depletion on Taech'u-point is more effective in depressing the systolic blood pressure than acupuncture on Gnagap-point.

무독성 호안블록의 수리학적 안정성에 관한 실험적 연구

김상우,구영민,김영도,박재현,Kim, Sang Woo,Koo, Young Min,Kim, Young Do,Park, Jae Hyeon 대한토목학회 2013 대한토목학회논문집 Vol.33 No.3

본 연구의 목적은 국내 하천 복원의 자연친화적인 설계를 위한 무독성 호안공법의 수리적 안정성을 검토하는 것이다. 최근 들어 공학적 효율 위주의 치수 기능만을 위한 하천관리 정책에서 벗어나 하천의 환경적 기능의 개선을 위한 생태하천 복원사업이 이루어지고 있다. 그러나 신규 호안공법에 대한 부적절한 수리학적 설계기준이 자주 홍수기 경제적 손실을 유발하고 있다. 사석 및 블록의 안정성에 관한 연구는 크게 하천에서 제방, 하상보호, 세굴방지 등의 목적과 바다에서 호안 또는 방조제의 축조에 따라 투하하는 사석의 안정성에 기초를 둔 연구가 대부분이며 경험식으로 이루어져 있다. 본 연구에서는 최고 유속 3.5 m/s인 고속수로를 제작하여 수리실험을 수행하였으며, 무독성 접착제를 이용한 블록공법에 대한 다양한 조건의 수리실험을 통해서 수리적 안정성을 위한 호안블록의 한계유속을 구하였다. The purpose of this study is to examine the hydraulic stability of non-toxic revetment technique for eco-friendly design of the domestic river restoration. Recently, instead of the flood control function-oriented river management policy for the engineering efficiency, the improvement of the environmental performance for the ecological river restoration project is implemented. However, the inappropriate hydraulic design criteria of the new revetment technique happen to the economic losses at flood season frequently. The hydraulic stability of the riprap and the block include the banks of rivers, riverbed protection, scour protection and so on. In this study, the high speed experimental channel was developed, which has the maximum velocity of 3.5 m/s, to perform the hydraulic experiments of the block method with non-toxic glue with various conditions to find the critical velocity of the revetment block for the hydraulic stability.

조구등이 MCAO 모델 흰쥐에서 gliosis 억제에 미치는 영향

김상우,김선애,송봉근,Kim, Sang-Woo,Kim, Sun-Ae,Song, Bong-Keun 대한한방내과학회 2010 大韓韓方內科學會誌 Vol.31 No.4

Objectives : In condition of brain infarction, irreversible axon damage occurs in central nerve system(CNS), because gliosis becomes physical and mechanical barrier to axonal regeneration. Reactive gliosis induced by ischemic injury such as middle cerebral artery occlusion is involved with up-regulation of GFAP and CD81. The current study is to examine the effect of the Uncariae Ramulus et Uncus on CD81 and GFAP expression in the rat brain following middle cerebral artery occlusion. Methods : In order to study ischemic injuries on brain, infarction was induced by middle cerebral artery occlusion(MCAO) using insertion of a single nylon thread, through the internal carotid artery, into a middle cerebral artery. Cresyl violet staining, cerebral infarction size measurement, immunohistochemistry and microscopic examination were used to detect the expression of CD81 and GFAP and the effect on the infarct size and pyramidal cell death in the brain of the rat with cerebral infarction induced by MCAO. Results : The following results were obtained 1. Measuring the size of cerebral infartion induced by MCAO in the rat after injection of Uncariae Ramulus et Uncus showed the size was decreased. 2. Intravenous injection of Uncariae Ramulus et Uncus showed pyramidal cell death protection in the hippocampus in the MCAO rat. 3. Water extract injection of Uncariae Ramulus et Uncus decreased GFAP expression significantly in the MCAO rat. 4. Uncariae Ramulus et Uncus water extract decreased CD81 expression in the MCAO rat. 5. The administration of water extract of Uncariae Ramulus et Uncus induced up-regulation of c-Fos expression significantly compared with MCAO. 6. The admistration of water extract of Uncariae Ramulus et Uncus increased ERK expression significantly compared with MCAO. Conclusion : We observed that Uncariae Ramulus et Uncus could suppress the reactive gliosis, which disturbs the axonal regeneration in the brain of the rat with cerebral infaction after MCAO by controlling the expression of CD81 and GFAP. The effect may be modulated by the up-regulation of c-Fos and ERK. These results suggest that Uncariae Ramulus et Uncus can be a candidate to regenerate CNS injury.

다중위성 및 현장관측을 이용한 동해남부 연안용승 발생 전후의 해양환경 특성

김상우,고우진,김성수,정희동,야마다게이꼬,Kim, Sang-Woo,Go, Woo-Jin,Kim, Seong-Soo,Jeong, Hee-Dong,Yamada, Keiko 해양환경안전학회 2010 해양환경안전학회지 Vol.16 No.4

본 연구에서는 하계 냉수대 발생과 관련하여 2007년 6월과 8월의 현장 및 위성에서 관측한 NOAA 해양표면수온과 SeaWiFS 해색 영상 및 QuikScat 자료를 이용하여 동해 남부해역의 수온과 클로로필 a 농도의 단기 변동과 바람을 살펴보았다. 특히, 동한난류 해역의 수온과 Chl-a의 공간적인 분포에 주목하였다. 현장관측 자료의 분석 결과, 울산 부근의 연안용승이 발생 이전인 6월의 클로로필 a 농도의 피크는 전체 조사 정점에서 50m 층에 보였고, 8월의 그 피크는 육지에 근접한 정점 4와 5에서는 10m 그리고 그 외 정점은 30m 층에 나타났지만 정점 5를 제외하고 그 농도는 6월보다 낮게 나타났다. 결과적으로, 클로로필 a 농도의 피크는 농도 차이는 있지만 8월이 6월보다 20-40m 얕은 층에 형성되었고, 이것은 남풍계열의 바람에 의한 연안용승으로 하부층의 영양염 공급 등과 관계하는 것 같다. 위성관측 수온과 클로로필 a 농도는 음의 상관관계를 보였고, 냉수가 발생한 곳에서 클로로필 a 농도는 고농도를 나타내었다. 또한, 남풍계열의 바람에 의한 영향과 동한난류의 이안은 연안에서 발생한 냉수와 Chl-a 등을 외해로 이동시키는 역할을 하였다. The objective of this paper is to explore the short-term variability of water temperature and chlorophyll a (Chl-a) derived from in-situ and satellite data (NOAA, Sea WiFS and QuikScat) in the upwelling region of the southeastern part of Korean Peninsula in June and August, 2007. Particularly we focused on the spatial variability of sea surface temperature(SST) and Chl-a in the East Korean Warm Current region. In the results of the in-situ data, the peaks of Chl-a in june was shown at a depth of 50m The peaks of Chl-a in August was shown at a depth of 10m at the stations 4 and 5 near the land, and a depth of 30m at the other stations. The Chl-a concentrations in August were also lower than those in june except for station 5. As a result, the peaks of Chl-a in August occurred at a depth of 20~40 m shallower than those of Chl-a in june. This indicates that the nutrient-rich water within the mixed layer depth may be immediately supplied by the coastal upwelling, which is due to the southerly component of wind. The relationship between SST and Chl-a showed a negative correlation, and the high concentration of Chl-a occurred in the cold water area. The southerly wind and the East Korean Warm Current influenced a remarkable offshore movement of the cold water and Chl-a near the coastal area.

청보리 사일리지 및 목건초 급여가 엘크 사슴의 생산성 및 경제성에 미치는 영향

김상우,서상원,김동훈,김재환,김영신,김관우,윤세형,Kim, Sang Woo,Suh, Sang Won,Kim, Dong Hoon,Kim, Jae Hwan,Kim, Young Sin,Kim, Kwan Woo,Yoon, Sei Hyung 한국초지조사료학회 2013 한국초지조사료학회지 Vol.33 No.1

본 연구는 사슴의 조사료 원으로 엘크사슴에 대한 청보리 사일리지 급여가 사슴의 사료섭취량, 체중변화 및 경제성에 미치는 영향을 구명하기 위하여 실시하였다. 엘크사슴 21두를 공시하여 건초구, 청보리 사일리지구 및 건초+청보리 사일리지구로 나누어 농후사료를 3.7 kg 정량급여 하고 조사료는 자유채식 시켰으며, 그 결과는 다음과 같다. 엘크사슴의 일당증체량은 건초구, 청보리 사일리지구 및 건초+청보리 사일리지구 혼합구가 각각 0.26, 0.36 및 0.44 kg으로 건초+청보리 혼합구가 가장 높았고, 엘크사슴의 청보리 사일리지 일일섭취량은 6.25~9.00 kg (풍건) 범위였으며, DM 섭취량은 건초구, 건초+청보리 사일리지 혼합구 및 청보리 사일리지 순으로 높은 경향을 보였다. 녹용 생산량은 건초구, 청보리 사일리지구 및 건초+청보리 사일리지구가 각각 8,037, 7,713 및 8,585 g으로 건초+청보리 사일리지 혼합구가 가장 많았다. 3개 처리구간 일당증체량, 녹용생산량 및 사료섭취량은 사슴의 개체차가 심하여 통계적으로 유의성은 인정되지 않았지만(p>0.05) 증체량 및 녹용산량은 증가하는 경향을 보였다. 경제성 분석에서는 건초+청보리 사일리지 혼합구가 건초 및 청보리 사일리지 단독급여구보다 소득지수가 29~43% 높게 나타났다. 이상의 결과를 종합적으로 고려할 때 사슴의 조사료 원으로 청보리 사일리지는 기호성에서 건초를 대체할 만큼의 섭취량을 가지므로 이용가능성이 있었으며, 조사료 원으로 연중 공급이 가능하고, 경제적인 측면에서도 건초보다 유리하여 농가에서 사슴의 조사료 원으로 사용이 가능할 것으로 사료된다. 또한 청보리 사일리지 급여 시에는 청보리 사일리지 단독 급여보다는 청보리와 건초를 각각 50%씩 혼합 급여하는 것이 일당증체량, 증체, 녹용생산량 및 경제성에서 가장 바람직한 것으로 사료된다. This study was conducted to determine the effect of dietary whole-crop barley silage on the daily feed intake, daily weight gain, velvet antler yield and economic efficacy in elk during growth. A total of 21 elk (average BW 303 kg, 5 years old) were allotted randomly to three treatments. The three treatments were T1 (hay diet), T2 (whole-crop barley silage), and T3 (50% hay + 50% whole-crop barley silage). The average daily weight gain of T3 was higher than the others throughout the entire experimental period. The average daily feed intake of elk in decreasing order was as follows; T1>T3>T2. The velvet antler yield was higher in T3 group (8,585 g) compared with T1 (8,037 g) and T2 (7,713 g). However, there were no significant differences in the average daily feed intake, average daily weight gain, or velvet antler yield (p>0.05). In economic efficacy, T3 was gained about 29~43% more value than T1 or T2. In conclusion, the mixed feeding of 50% hay and 50% whole-crop barley silage was more effective than feeding hay of barley alone, in terms of average daily weight gain, velvet antler yield, and economic efficacy in elk.

MODIS 이미지를 이용한 지표특성에 따른 토양수분의 시·공간적 분포 특성

김상우,신용철,이태화,이상호,최경숙,박윤식,임경재,김종건,Kim, Sangwoo,Shin, Yongchul,Lee, Taehwa,Lee, Sang-Ho,Choi, Kyung-Sook,Park, Younshik,Lim, Kyoungjae,Kim, Jonggun 한국농공학회 2017 한국농공학회논문집 Vol.59 No.6

In this study, we analyzed the impacts of land surface characteristics on spatially and temporally distributed soil moisture values at the Yongdam and Soyang-river dam watersheds in 2014 and 2015. The soil moisture, NDVI (Normalized Difference Vegetation Index) and temperature values at the spatio-temporal scales were estimated using satellite-based MODIS (MODerate Resolution Imaging Spectroradiometer) products. Then the Pearson correlations between soil moisture and land surface characteristics (NDVI, temperature and DEM-digital elevation model) were estimated and analyzed, respectively. Overall, the monthly soil moisture values at the time step were highly influenced by the precipitation amounts. Also, the results showed that the soil moisture has the strong correlation with DEM while the temperature was inversely correlated with the soil moisture. However the monthly correlations between NDVI and soil moisture were highly varied along the time step. These findings indicated that water loss near the land surface are highly occurred by soil and plant activities as evapotranspiration and infiltration during the no/less precipitation period. But the high precipitation amounts reduce the impacts of land surface characteristics because of saturated condition of land surface. Thus these results demonstrated that soil moisture values are highly correlated with land surface characteristics. Our findings can be useful for water resources/environmental management, agricultural drought, etc.