하나로 핵연료 시험루프 주냉각수 계통의 유량제어에 대한 유동해석

박용철(Young-Cheol Park),이용섭(Yong-Sub Lee),지대영(Dae-Yong Chi) 한국유체기계학회 2008 유체기계 연구개발 발표회 논문집 Vol.2008 No.-

A nuclear fuel test loop (after below, FTL) is installed in the IR1 of an irradiation hole in NANARO far testing the neutron irradiation characteristics and thermo hydraulic characteristics of a fuel loaded in a light water power reactor or a heavy water power reactor. There is an in-pile section (IPS) and an out-pile section (OPS) in this test loop. When HANARO is operated normally, the fuel loaded into the IPS has a nuclear reaction heat generated by a neutron irradiation, To remove the generated heat and to maintain the operation conditions of the test fuel, a main cooling water system (MCWS) is installed in the OPS of the FTL. The MCWS is composed of a main cooler, a pressurizer, two circulation pumps. a main heater, an interconnection pipe line and instruments. The interconnection pipeline is a closed loop which is connected to an inlet and an outlet of the IPS respectively. The MCWS is under a cold function test during a start-up period. This paper describes the system flow network analysis results of the flow control of a main cooling water system in the HANARO fuel test loop. It was confirmed through the results that the flow was met the system design requirements.

하나로 비상보충수의 노심 주입유량 시험 결과에 대한 고찰

박용철(Yong-Chul Park),이용섭(Yong-Sub Lee),최영산(Young-San Choi),정환성(Hoan-Sung Jung),임인철(In-Cheol Lim) 대한기계학회 2007 대한기계학회 춘추학술대회 Vol.2007 No.10

When the water level of the reactor pool descends to an extremely low level due to a loss of reactor pool water accident in HANARO, a multi-purpose research reactor of a 30 MWth, the emergency water stored in the tank should be fed to the core by a gravity force. Last year, the reactor pool water was temporarily transferred to the emergency cooling water storage tank. And the water level came down to EL 77.5 m, 0.4 m above the extremely low level to install the in-pile section of a Fuel Test Loop in the reactor core. When the water was re-transferred into the reactor pool, an emergency water injection test was performed. This paper describes the test results and a consideration of the results. It was confirmed through the test that the injection flow rate was maintained above the design injection flow rate by setting the flow control valve at 3.5 turns to a partially open position.

카사바 당화액을 이용한 실험실용 및 산업용 효모의 에탄올 발효성능 비교

진영욱 ( Young Wook Chin ),김진우 ( Jin Woo Kim ),박용철 ( Yong Cheol Park ),서진호 ( Jin Ho Seo ) 한국미생물생명공학회(구 한국산업미생물학회) 2012 한국미생물·생명공학회지 Vol.40 No.3

In order to investigate the ethanol fermentation properties of alcohol yeasts a laboratorial strain (CEN.PK2-1D) and two industrial alcohol yeasts (JHS100 and JHS200) of Saccharomyces cerevisiae were cultured in a pure YP medium with 300 g/L glucose and cassava hydrolysate. Spot assay and cell viability tests showed that both the JHS100 and JHS200 strains exhibited higher ethanol tolerance than the CEN.PK2-1D strain. The JHS100 strain demonstrated the highest cell growth, glucose consumption and ethanol production. In particular, an anaerobic batch fermentation of the JHS100 strain using cassava hydrolysate with 250 g/L glucose resulted in a 106.1 g/L ethanol concentration, 0.42 g/g ethanol yield and 3.15 g/L-hr ethanol productivity, which were 53%, 13%, 53% higher than the corresponding values for the CEN.PK2-1D strain. By changing the pure YP medium to cassava hydrolysate, 19% and 17% decreases in ethanol yield and productivity for the CEN.PK2-1D strain were observed, whereas the cultures of the JHS100 and JHS200 stains showed similar ethanol pro-ductivities and only an 8% decrease in ethanol yield. Furthermore, the JHS100 and JHS200 stains produced lower levels of glycerol and acetate byproducts than the CEN.PK2-1D strain. Consequently, the outstanding ethanol fermentation performance of the industrial strains might be owing to rapid cell growth, high ethanol tolerance, low nitrogen requirements and the low formation of by-products.

국내 스트레이트 아스팔트의 거동 특성 연구

김남호,황성도,박용철,Kim, Nam-Ho,Hwang, Sung-Do,Park, Young-Cheol 한국도로학회 1999 한국도로포장공학회 논문집 Vol.1 No.2

본 논문은 국내 정유사에서 생산되는 도로 포장용 아스팔트에 대하여 노화에 따른 거동 특성을 파악하였다. 이를 위해 국내의 5개 정유회사에 생산되는 두가지 등급의 아스팔트 제품(침입도 85-100, 침입도 60-70)을 포함한 총 9종에 대하여 노화 단계별(노화 이전, 단기노화, 장기노화)로 국내 스트레이트 아스팔트의 침입도$(25^{\circ}C)$, 점도$(50^{\circ}C\;135^{\circ}C)$, 연화점, 및 DSR 시험$(-20^{\circ}C\sim30^{\circ}C)$을 수행하여, 아스팔트의 물성 변화 특성을 고찰하였다. 연구 결과, 국내 스트레이트 아스팔트의 거동은 고온($60^{\circ}C$근방) 및 상온$(10-30^{\circ}C)$범위에서 정유사 제품에 따라 상당한 차이를 나타내었으며, 저온의 경우에는 정유사 제품이나 등급에 관계없이 거의 유사한 거동을 나타내었다. 따라서 어느 정유사의 아스팔트를 사용하는가에 따라, 저온에서의 온도 균열에 대한 저항성은 다소 비슷한 수준일 것으로 판단되지만, 소성변형 및 피로 균열에 대한 저항성이 상이하게 나타날 것으로 판단된다. This study was based on the evaluation of 9 asphalts that were produced in five major Korean refineries. The study was concentrated to identify the problems of the current asphalt specification (KS M 2201) and to determine the ranges of visco-elastic asphalt behavior. As a conventional asphalt property. asphalt penetration, ring and ball(R&B) softening point, asphalt viscosity, and flash point of asphalt were measured. Also Dynamic Shear Rheometer (DSR) were used to evaluate visco-elastic properties of asphalts in the $-20^{\circ}C$ through $30^{\circ}C$ temperature range. These properties before and after the short-term (RTFO) and long-term (PAV) aging were compared and analyzed to achieve the research objectives. The conclusion from this study can be summarized by the followings. The low temperature rheological behavior of all the straight asphalt from five major Korean refineries is similar regardless of asphalt grade. In the mean while, the rheological behavior at high and intermediate temperature of Korean straight asphalt varies depending on asphalt grade.

남극 지진 및 빙권 신호 관측을 위한 초광대역 지진계 설치

이원상 ( Won Sang Lee ),박용철 ( Yong Cheol Park ),윤숙영 ( Suk Young Yun ),서기원 ( Ki Weon Seo ),이태규 ( Tae Gyu Yee ),최한진 ( Han Jin Choe ),윤호일 ( Ho Il Yoon ),채남이 ( Na Myi Chae ) 한국지구물리·물리탐사학회 2012 지구물리와 물리탐사 Vol.15 No.3

극지연구소는 2010 ~ 2011년 제 24차 남극하계탐사기간 동안 남극 킹조지섬에 3성분 초광대역 지진계를 성공 적으로 설치하였다. 미국 IRIS PASSCAL에서 개발한 지진관측시스템을 활용하였으며, 이는 POLENET 지진관측시스템 과 완벽히 호환된다. 지진계설치 및 운용의 목적은 크게 두가지로 나누어 지는데, 첫번째로 킹조지섬 주변의 지진 및 빙 권관련 신호를 관측하는데 있으며, 두번째로는 극한환경에서의 지진관측장비 성능검사이다. 관측이 성공적으로 수행된다 면, 다음 목표로 관측시스템의 추가확보를 통하여 남극반도 라르센 빙붕시스템과 같은 빙붕 주변으로 관측장소를 이동하 여 지권과 빙권간 상호작용을 이해하고, 빙권의 움직임등 동역학적인 해석을 위한 연구를 수행하고자 한다. 이 보고서에 서 우리는 지진파 배경잡음분석을 통하여 지진관측시스템 성능 및 특성 파악에 관한 내용과 관측시스템 운용관련 정보를 제공하고자 한다. Korea Polar Research Institute (KOPRI) has successfully installed two autonomous very broadband threecomponent seismic stations at the King George Island (KGI), Antarctica, during the 24th KOPRI Antarctic Summer Expedition (2010 ~ 2011). The seismic observation system is originally designed by the Incorporated Research Institutions for Seismology Program for Array Seismic Studies of the Continental Lithosphere Instrument Center, which is fully compatible with the Polar Earth Observing Network seismic system. The installation is to achieve the following major goals: 1. Monitoring local earthquakes and icequakes in and around the KGI, 2. Validating the robustness of seismic system operation under harsh environment. For further intensive studies, we plan to move and install them adding a couple more stations at ice shelf system, e.g., Larsen Ice Shelf System, Antarctica, in 2013 to figure out ice dynamics and physical interaction between lithosphere and cryosphere. In this article, we evaluate seismic station performance and characteristics by examining ambient noise, and provide operational system information such as frequency response and State-Of-Health information.

수신함수와 표면파 분산곡선의 복합역산 및 수신함수 H-K 중첩법을 이용한 원주 KS31 지진관측소 하부의 S파 지각 속도구조

전태현 ( Tae Hyeon Jeon ),김기영 ( Ki Young Kim ),박용철 ( Yong Cheol Park ),강익범 ( Ik Bum Kang ) 한국지구물리·물리탐사학회 2012 지구물리와 물리탐사 Vol.15 No.1

원주 KS31 광대역 지진관측소 하부의 S파 속도구조를 구명하기 위해서, 2002~2009년 사이에 기록된 규모 Mw 5.5 이상의 297개 원거리 지진 이벤트 자료로부터 구한 수신함수와 표면파 분산곡선의 복합역산 및 H-K 영역에서의 중 합법을 적용하였다. 분석 결과는 이 관측소 반경 수십 km 이내의 모호면 평균 깊이가 32.4±0.5 km로 거의 평탄하게 놓여 있음을 지시한다. 이 지역 지각의 평균 S파 속도는 3.69 km/s이고, P파와 S파 속도비, Vp/Vs가 1.72±0.04로 나타나서 전형적인 육지지각의 특성을 보인다. 수신함수 1 s에 나타난 음 위상은 KS31 관측소 하부의 상부지각 l0~18 km 깊이에 S파 저속도층이 존재함을 지시한다. To estimate the S-wave velocity structure beneath the KS3I broad-band station in Wonju, Korea, we used H-K stacking and joint inversion of receiver functions and surface-wave dispersion curves derived from 297 teleseismic events (Mw>5.5) recorded during the period between 2002 and 2009. We thereby determined that the average depth to a nearly flat Moho is 32.4 ± 0.5 km within tens of kilometer radius of the seismic station. For the crust at this location, we estimate an average shear-wave velocity of 3.69 km/s and a ratio of P-to S-wave velocities, Vp/Vs of 1.72 ± 0.04, as is typical for continental crust. A negative phase in the receiver functions at I s indicates the presence of a shear-wave low velocity layer in a depth interval of 10 to 18 km in the upper crust beneath the KS3l station.

단보 : 이동식 중력계(gPhone)를 활용한 장주기 지진 이벤트 관측

이원상 ( Won Sang Lee ),서기원 ( Ki Weon Seo ),엄주영 ( Joo Young Eom ),신동훈 ( Dong Hoon Sheen ),이춘기 ( Choon Ki Lee ),박용철 ( Yong Cheol Park ),윤숙영 ( Suk Young Yun ),유현재 ( Hyun Jae Yoo ) 한국지구물리·물리탐사학회 2015 지구물리와 물리탐사 Vol.18 No.1

중력계는 주로 지하 광물자원 탐사 및 지구조석과 같은 장주기 이벤트를 관측하는데 사용되고 있다. 최근 연구자들은 이 중력계를 이용하여 대형 원거리 지진 및 지진상시잡음 관측과 같은 몇몇 새롭고 흥미로운 사실들을 발견하였다. Micro-g LaCoste사의 gPhone에 적용된 zero-length spring suspension 기술은 초저주파 신호도 훌륭히 관측 가능하게하며, 이는 Earth’s hum이나 심지어 대형 지진해일 등을 관측하는데 큰 도움을 줄 수 있음을 시사한다. 이 연구에서는 충남 금산에서 2008년 11월 부터 2009년 7월까지 9개월간 임시로 설치/운영하였던 gPhone 자료를 분석하여 원거리 대형 지진관측 및 상시지진잡음의 계절적 변화에 관한 사전결과를 보고하고자 한다. A gravity meter has been used for exploring subsurface mineral resources and monitoring long-period events such as Earth tides. Recently, researchers found several other intriguing features that we could even detect large teleseismic earthquakes and monitor seismic ambient noise using gravimeters. The zero-length spring suspension technology gives the gPhone (Micro-g LaCoste) excellent low frequency sensitivity, which may have implications for investigating much longer-period natural events (e.g., Earth’s hum, tsunami waves, etc.). In this study, we present preliminary results through temporary operation of the gPhone at Geumsan in South Korea for 9 months (Nov. 2008- Jul. 2009). The gPhone successfully recorded large teleseismic events and showed a clear seasonal variation of the Double frequency microseisms during its operation period.