변위제어 조건에 따른 철도판형교 장대레일의 부가축응력 해석

채수호(Chae, Sooho),윤건우(Yoon, Keonwoo),최상현(Choi, Sanghyun) 한국강구조학회 2019 한국강구조학회 학술대회 발표집 Vol.30 No.1

레일이음매로 인한 무도상 판형교의 동적응답 분석

채수호(Sooho Chae),유용(Yong Yoo),박예진(Yejin Park),최상현(Sanghyun Choi) 한국철도학회 2018 한국철도학회논문집 Vol.21 No.11

경전철 교량의 종방향 하중 발생 특성 분석

채수호(Chae, Sooho),신정렬(Shin, Jeong-Ryol),최상현(Choi, Sanghyun) 한국강구조학회 2020 한국강구조학회 학술대회 발표집 Vol.31 No.1

고무차륜 경전철 차량의 시 · 제동으로 인한 교량의 하중 효과 분석

채수호(Chae, Sooho),신정열(Shin, Jeong-Ryol),최상현(Choi, Sanghyun) 한국강구조학회 2020 韓國鋼構造學會 論文集 Vol.32 No.2

기공형성제 크기와 함량이 다공질 지르코니아 세라믹스의 가공율과 강도에 미치는 영향

채수호,김영욱,송인혁,김해두,배지수,Chae, Su-Ho,Kim, Young-Wook,Song, In-Hyuek,Kim, Hai-Doo,Bae, Ji-Soo 한국세라믹학회 2009 한국세라믹학회지 Vol.46 No.1

Using zirconia and poly (methyl methacrylate-coethylene glycol dimethacrylate) (PMMA) microbeads, macroporous zirconia ceramics were fabricated by a simple pressing method. Effects of template size and content on microstructure, porosity, and flexural and compressive strengths were investigated in the processing of the macroporous zirconia ceramics. Three different sizes of microbeads (8, 20, and $50{\mu}m$) were used as a template for fabricating the macroporous ceramics. The porosity increased with increasing the template size at the same template content. The flexural and compressive strengths were primarily influenced by the porosity rather than the template size. However, the strengths increased with decreasing the template size at the same porosity. By controlling the template size and content, it was possible to produce macroporous zirconia ceramics with porosities ranging from 58% to 75%. Typical flexural and compressive strength values at 60% porosity were ${\sim}30\;MPa$ and ${\sim}75\;MPa$, respectively.

다공질 지르코니아 세라믹스의 기공율 제어

채수호,엄정혜,김영욱,송인혁,김해두,배지수,나상문,김승일,Chae, Su-Ho,Eom, Jung-Hye,Kim, Young-Wook,Song, In-Hyuek,Kim, Hai-Doo,Bae, Ji-Soo,Na, Sang-Moon,Kim, Seung-Il 한국세라믹학회 2008 한국세라믹학회지 Vol.45 No.1

A simple pressing process using zirconia and microbead for fabricating porous zirconia ceramics is demonstrated. Effects of microbead content and sintering temperature on microstructure, porosity, compressive and flexural strengths were investigated in the processing of porous zirconia ceramics using microbead as a pore former. By controlling the microbead content and the sintering temperature, it was possible to produce porous zirconia ceramics with porosities ranging from 43% to 70%. Typical compressive and flexural strength values at ${\sim}50%$ porosity were ${\sim}150\;MPa$ and ${\sim}35\;MPa$, respectively.

프릿을 이용한 다공질 SiC 세라믹스의 저온 제조 공정 및 물성

채수호,김영욱,송인혁,김해두,배지수,나상문,김승일,Chae, Su-Ho,Kim, Young-Wook,Song, In-Hyuck,Kim, Hai-Doo,Bae, Ji-Soo,Na, Sang-Moon,Kim, Seung-Il 한국세라믹학회 2009 한국세라믹학회지 Vol.46 No.5

Porous frit-bonded SiC ceramics were successfully prepared at a temperature as low as $800^{\circ}C$ from SiC, frit, and microbeads (glass or polymer). The effects of SiC starting particle size and microbead addition on microstructure, porosity, and flexural strength were investigated. The addition of hollow glass microbead improved the strength of frit-bonded SiC ceramics without the loss of porosity by acting additional binder phase between SiC grains. The 65 ${\mu}m$-sized SiC resulted in lower porosity and higher strength than 50 ${\mu}m$-sized SiC because of higher packing density. Typical flexural strengths of frit-bonded SiC were 23 MPa at 46% porosity and 19 MPa at 49% porosity.

주산기에 발견된 수신증의 자연 경과와 치료 방침

채수호,이지혁,진동규,박관현,백경훈,Chae Soo-Ho,Lee Ji-Hyuk,Jin Dong-Kyu,Park Kwan-Hyun,Paik Kyung-Hoon 대한소아신장학회 2006 Childhood kidney diseases Vol.10 No.1

목적 :신생아 수신증은 임신의 약 4.5-7% 정도로 흔하게 나타날 뿐 아니라 산전 초음파의 발달과 함께 조기진단이 가능한 질환이다. 그러나 그 자연 경과에 대한 이해 부족으로, 수술적 중재술의 적절한 시기에 대한 합의가 이루어지지 않은 상태이다. 저자들은 신생아 수신증의 자연경과에 대한 이해와 수술의 위험요소를 분석함으로써, 적절한 치료지침을 제시하고자 하였다. 방법 : 2001년 4월부터 2005년 4월까지 본원에서 태어난 신생아 중, 주산기에 시행한 신 초음파 검사에서 신생아 수신증으로 진단된 환아를 대상으로 하였다. 총 2회 이상의 초음파 검사를 통한 경과 관찰을 하였던 환아들 중, 6개월 이상 추적관찰된 총 69명의 환자를 대상으로 하였다. 환자군은 주산기 신장 초음파에서 신우전후경 길이를 기준으로 분류하였다 각각 환자의 신장 초음파 검사에서 신우전후경 길이 및 SFU 지수를 측정하였고, $^{99m}Tc-MAG3$ 검사 결과를 바탕으로 분석하였다. 수술은 정해진 기준에 따라 시행하였다. 결과 : 신우전후경의 길이가 10 mm 이상인 환자군에서, 10 mm 미만인 환자군에 비해 수술적 중재술을 필요한 경우가 많았다. 또한 SFU 지수가 3 이상인 경우에서, 수술의 빈도가 높아, SFU 지수 3 미만인 환자군과 유의한 차이를 두었다. MAG3 검사 중, 상대 신기능은 수술과의 연관성을 찾기 어려웠으나, 신장 폐색의 정도와 수술 여부와 상호 관계가 있는 것으로 나타났다. 결론 : 신생아 수신증에서 주산기 신장 초음파 검사 상, 신우전후경의 길이가 10 mm가 넘거나, SFU 지수가 3 이상이거나, MAG3 검사 결과 상 폐색이 의심되는 경우에는 수술적 중재술을 통한 적극적인 치료를 고려하는 것이 추천된다. 그리고 신우전후경의 길이가 10 mm 미만이거나 SFU 지수가 2 이하인 경우, 신생아 수신증의 자연 경과를 관찰할 수 있으나 정기적인 경과 관찰이 필요하다. Purpose : Neonatal hydronephrosis is diagnosed with an incidence of 4.5-7% of pregnancies. Recently, early detection of neonatal hydroneprosis with antenatal ultrasonography has be-come possible. But consensus about its management has not been reached, especially concerning surgical intervention. The purpose of this study is to analyze the natural course of neonatal hydronephrosis and to determine the guideline of surgical intervention and follow up study. Methods : Sixty nine hydronephrotic kidneys were confirmed from April 2001 to April 2005. All cases were rechecked by ultrasonography once at least and had a minimum follow-up of 6 months. We classified the patients into 4 groups according to the anterior posterior pelvic diameter(APPD) on perinatal ultrasonography. Ultrasonography to measure the APPD diameter and Society for Fetal Urology(SFU) grade, $^{99m}Tc-MAG3$ scan were done to a set protocol. Pyeloplasty was peformed according to the protocol. Results : Pyeloplasty was not needed in most cases where the APPD was below 10 mm and where the SFU grade were less than grade 3. Many cases with APPD 10 mm above or SFU grade III above had undergone pyeloplasty. We found a correlation between obstruction grade on MAG3 scan and whether surgery was performed or not. Conclusion : If APPD is above 10 mm, SFU grade is above grade 3 or urinary tract obstruction is suspected by MAG3 scan, pyeloplasty must be considered. In cases where APPD is below 10mm and SFU grade is less than grade 3, we can observe the natural course of neonatal hydronephrosis with consecutive follow-up. (J Korean Soc Pediatr Nephrol 2006;10:33-39)

농업분야 ODA 효율성 제고 방안에 관한 연구

김윤두(Yoon-Doo Kim),채수호(Sue-Ho Chae),이상덕(Sang Duk Lee) 한국산업경제학회 2016 산업경제연구 Vol.29 No.3

본 연구는 국제농업기술협의체를 통한 ODA 사업인 AFACI 사업 성과분석을 통해 향후 농업분야 ODA 사업의 효율적 추진방향을 제시하고자하였다. 이를 위해 AFACI 사업에 참여하고 있는 각 회원국 사업담당자를 대상으로 AFACI 사업의 과정적 사업성과를 도출하였으며, AFACI 사업 주관부서 담당자 및 전문가를 통한 AHP분석 결과를 바탕으로 개별 사업간 성과를 분석하였다. 분석결과 참여국가 간 네트워크 구축이 활발하게 이루어지고 관련 이해관계자간 의사소통이 원활할수록 사업의 성과가 높게 나타났으며, 농업인들에게 직 간접적으로 소득향상에 미치는 영향이 클수록, 사업 대상 범위(품목, 분야 등)가 다양 할수록 사업성과가 높게 나타났다. 이에 따라 향후 농업분야 ODA 사업은 첫째, 관련된 협의체를 구성하여 다자간 ODA 사업을 시행함으로써 효율성을 제고하고, 둘째, 수원국 간 또는 수원국과 공여국 간의 의사소통과 네트워크 중심의 ODA 사업 추진이 필요한 것으로 나타났다. 셋째, 과거와 같이 단순한 자금지원이 아닌 수원국에서 필요로 하는 농업분야의 기술 등에 대한 지원과 수원국 자력으로 지속할 수 있는 협력체계 구축기반을 지원할 필요가 있다. 마지막으로 기존에 수원국에서 접근하기 어려웠던 농업분야에 대한 사업들을 추진함으로써 수원국 농업의 질적 향상을 도울 필요가 있다고 판단된다. This study was designed to present suggestions on the promotion of the ODA projects through an analysis of the performance of the AFACI project, one of the ODA directed by the ‘International Agriculture Technical Cooperation Initiative’ of Korea. To provide the suggestions mentioned above, the performance of the processes of AFACI project was analyzed by the aid of the principal investigators of each country, the member of AFACI project. The performance of project was also examined and compared via the experts and the department of management of the AFACI project by using the analysis of AHP (Analytic Hierarchy Process). The results obtained from the analyses showed the projects of the countries constructed international network of fluent communication among stakeholders marked higher performance than other projects. In addition, the projects having greater effects on the increase of the income of people engaged in agricultural field also exhibited higher performance. Based on theresults obtained thereof, following suggestions on the promotion of ODA projects in the field of agriculture in Korea were established as in the following: Firstly, The ODA projects should be promoted through the established multilateral cooperation to raise the efficiency thereof. Secondly, The ODA projects should be promoted based on the established network of fluent communication among therecipient and donor countries. Finally, the projects in the fields where the recipient countries would have difficulties to achieve spontaneous development independently should be promoted to help the qualitative improvement of the agriculture in recipient countries.

조류인플루엔자(AI)와 육계가격 간의 관계분석

홍성규(Hong, Sung-Kyu),채수호(Chae, Sue-Ho),김윤두(Kim, Yoon-Doo) 한국농식품정책학회 2015 농업경영정책연구 Vol.42 No.4

The paper attempted to analyze the long-term and short-term impacts of avian influenza (AI) on broiler prices in each chicken distribution stage in Korea. To this end, the paper utilized the farm price, wholesale price (after slaughtering), and consumer price of the broilers and applied the AI occurrence periods as dummy variables. From the analysis, both the results of the unit root test considering structural break and the results of the unit root test without consideration of structural break were shown to be non-stationary time series so it was shown that the structural break did not affect the stationarity of the time series. However, from the cointegration test conducted considering structural break and the cointegration test conducted without consideration of structural break, changes appeared in the long run equilibrium, that is, the cointegration test when considering the structural break. In other words, occurrence of AI was shown to affect the long run equilibrium relationship of the prices in each stage of the long term distribution. From the analysis by VECM (Vector Error Correction Model), when deviations in prices occur between each distribution stage with structural changes, the wholesale price (after slaughtering) was shown to lead them to the long run equilibrium relationship. The AI has exhibited the tendency to occur every year since 2014, which is different from the other animal diseases. Considering the above points, it is considered that occurrence of AI will affect the consumption and prices insignificantly in the future. However, it is considered that measures to stabilize the wholesale price through management and supply and demand control of slaughtering broiler number will be necessary since AI occurrence was affecting the long run equilibrium price from the analyze results.