포화상태에 놓인 C-Type 액체수소 탱크의 슬로싱이 열 유속과 BOG에 미치는 변화의 수치적 분석

이진호,황세윤,이성제,이장현,Lee, Jin-Ho,Hwang, Se-Yun,Lee, Sung-Je,Lee, Jang Hyun 한국전산구조공학회 2022 한국전산구조공학회논문집 Vol.35 No.5

본 논문은 슬로싱 상태에 놓인 포화 상태 액체수소탱크에서 열 유속 및 BOG(Boil-off gas)의 경향을 다루고 있다. 특히, 액체-기체간의 침투 및 혼합에 의한 열 교환에 관심을 두었다. 먼저, VOF(Volume of fluid)와 Eulerian 기반의 다상 유동모델로 모형 슬로싱 실험을 모사하여 압력을 예측하고 계측된 값과 비교하였다. 자유 수면 및 충격 압력 실험 결과와 해석 결과를 비교하였으며, 유체의 속도 예측에서 정확할 수 있음을 간접적으로 증명하였다. 그리고 2차원의 Type-C 원통형 수소탱크를 대상으로 다상열유동해석을 수행하였다. 이때 포화상태에 놓인 액체 및 기체수소를 가정하고, 해석을 통해 각 상간의 혼합에 의한 열 교환의 수준을 확인하고자 하였다. 단, 상간의 열 교환만을 관심으로 두고 있었으므로 질량전달 및 기화모델은 해석에서 제외하였다. 최종적으로 상의 혼합으로 인해 액체수소로 유입되는 열 유속의 기여도에 대하여 정리하였다. 또한 액체수소로 유입되는 열 유속과 집중 질량 기반의 간이식을 통해 BOG 발생량 및 경향을 예측하고 분석하였다. This study was conducted to predict the tendency for heat exchange and boil-off gas (BOG) in a liquefied hydrogen tank under sloshing excitation. First, athe fluid domain excited by sloshing was modeled using a multiphase-thermal flow domain in which liquid hydrogen and hydrogen gas are in the saturated state. Both the the volume of fluid (VOF) and Eulerian-based multi-phase flow methods were applied to validate the accuracy of the pressure prediction. Second, it was indirectly shown that the fluid velocity prediction could be accurate by comparing the free surface and impact pressure from the computational fluid dynamics with those from the experimental results. Thereafter, the heat ingress from the external convective heat flux was reflected on the outer surfaces of the hydrogen tank. Eulerian-based multiphase-heat flow analysis was performed for a two-dimensional Type-C cylindrical hydrogen tank under rotational sloshing motion, and an inflation technique was applied to transform the fluid domain into a computational grid model. The heat exchange and heat flux in the hydrogen liquid-gas mixture were calculated throughout the analysis,, whereas the mass transfer and vaporization models were excluded to account for the pure heat exchange between the liquid and gas in the saturated state. In addition, forced convective heat transfer by sloshing on the inner wall of the tank was not reflected so that the heat exchange in the multiphase flow of liquid and gas could only be considered. Finally, the effect of sloshing on the amount of heat exchange between liquid and gas hydrogen was discussed. Considering the heat ingress into liquid hydrogen according to the presence/absence of a sloshing excitation, the amount of heat flux and BOG were discussed for each filling ratio.

비수직 입사 비상관 지진파에 의한 원전 시설물의 지진 응답

이진호,Lee, Jin Ho 한국지진공학회 2022 한국지진공학회논문집 Vol.26 No.6

Based on the random-vibration-theory methodology, dynamic responses of nuclear facilities subjected to obliquely incidental and incoherent earthquake ground motions are calculated. The spectral power density functions of the 6-degree-of-freedom motions of a rigid foundation due to the incoherent ground motions are obtained with the local wave scattering and wave passage effects taken into consideration. The spectral power density function for the pseudo-acceleration of equipment installed on a structural floor is derived. The spectral acceleration of the equipment or the in-structure response spectrum is then estimated using the peak factors of random vibration. The approach is applied to nuclear power plant structures installed on half-spaces, and the reduction of high-frequency earthquake responses due to obliquely incident incoherent earthquake ground motions is examined. The influences of local wave scattering and wave passage effects are investigated for three half-spaces with different shear-wave velocities. When the shear-wave velocity is sufficiently large like hard rock, the local wave scattering significantly affects the reduction of the earthquake responses. In the cases of rock or soft rock, the earthquake responses of structures are further affected by the incident angles of seismic waves or the wave passage effects.

루우버핀형 고밀도 열교환기에 대한 연구동향

이진호,전창덕,Lee, J.H.,Jeon, C.D. 대한설비공학회 1996 설비저널 Vol.25 No.2

Polydioxanone/pluronic F127 담체에 유입된 골막기원세포의 조골활성

이진호,오세행,박봉욱,하영술,김덕룡,김욱규,김종렬,변준호,Lee, Jin-Ho,Oh, Se-Heang,Park, Bong-Wook,Hah, Young-Sool,Kim, Deok-Ryong,Kim, Uk-Kyu,Kim, Jong-Ryoul,Byun, June-Ho 대한악안면성형재건외과학회 2009 Maxillofacial Plastic Reconstructive Surgery Vol.31 No.6

Three-dimensional porous scaffolds play an important role in tissue engineering strategies. They provide a void volume in which vascularization, new tissue formation, and remodeling can occur. Like any grafted materials, the ideal scaffold for bone tissue engineering should be biocompatible without causing an inflammatory response. It should also possess biodegradability, which provides a suitable three-dimensional environment for the cell function together with the capacity for gradual resorption and replacement by host bone tissue. Various scaffolds have already been developed for bone tissue engineering applications, including naturally derived materials, bioceramics, and synthetic polymers. The advantages of biodegradable synthetic polymers include the ability to tailor specific functions. The purpose of this study was to examine the osteogenic activity of periosteal-derived cells in a polydioxanone/pluronic F127 scaffold. Periosteal-derived cells were successfully differentiated into osteoblasts in the polydioxanone/pluronic F127 scaffold. ALP activity showed its peak level at 2 weeks of culture, followed by decreased activity during the culture period. Similar to biochemical data, the level of ALP mRNA in the periosteal-derived cells was also largely elevated at 2 weeks of culture. The level of osteocalcin mRNA was gradually increased during entire culture period. Calcium content was detactable at 1 week and increased in a time-dependent manner up to the entire duration of culture. Our results suggest that polydioxanone/pluronic F127 could be a suitable scaffold of periosteal-derived cells for bone tissue engineering.

싱가포르 Transmission cable tunnel contract EW2 프로젝트

이진호,정민영,최완규,Lee, Jin-Ho,Jeong, Min-Yeong,Choe, Wan-Gyu 한국터널지하공간학회 2014 자연, 터널 그리고 지하공간 Vol.16 No.5

표준.시험인증 기술 동향 - SHVC 표준 기술 동향

이진호,강정원,이하현,최진수,Lee, Jin-Ho,Gang, Jeong-Won,Lee, Ha-Hyeon,Choe, Jin-Su 한국정보통신기술협회 2014 TTA저널 Vol.152 No.-

매괴화(??花) 에탄올추출물이 α-MSH로 유도된 과색소 형성 억제와 작용기전 연구

이진호,인명희,강석훈,문연자,우원홍,임규상,Lee, Jin-Ho,In, Myung-Hee,Kang, Suk-Hoon,Mun, Yeun-Ja,Woo, Won-Hong,Lim, Kyu-Sang 대한한방안이비인후피부과학회 2015 한방안이비인후피부과학회지 Vol.28 No.1

Objective : This study investigated the inhibitory mechanism of the hypopigmentating effects on ethanol extract of Rosae rugosae Flos (ERR) that has not yet been examined. Methods : We analyzed the anti-melanogenic effects of ethanol extracts from Rosae rugosae Flos by tyrosinase activity, melanin contents. We also examined protein expression levels of tyrosinase, TRP-1, TRP-2, MITF and ERK by western blot analysis in melanoma cells. Results : In this investigation, ERR effectively reduced ${\alpha}$-MSH-stimulated melanin synthesis by suppressing expression of tyrosinase and tyrosinase-related protein-1 (TRP-1). On the other hand, the expression of tyrosinase-related protein-2 (TRP-2) were not affected by treatment with ERR. ERR inhibited the expression of microphthalmia-associated transcription factor (MITF) as a key transcription factor for tyrosinase expression regulating melanogenesis. The upstream signaling pathway including cAMP response element-binding protein (CREB) and MAPKs were also inhibited by ERR. Pretreatment with PD98059, ERK inhibitor, attenuated the inhibitory effect of ERR on ${\alpha}$-MSH-induced tyrosinase activity. Conclusions : Our study suggested that the anti-melanogenic activity of ERR is correlated with the suppression of tyrosinase gene through CREB/MITF/ERK pathway.

함정 탑재 V/UHF 안테나의 전계 특성 분석

이진호,권준혁,송기환,Lee, Jin-Ho,Kwon, Joon-Hyuck,Song, Ki-Hwan 한국군사과학기술학회 2008 한국군사과학기술학회지 Vol.11 No.6

Analysis of the electromagnetic environment on topside of a ship is needed for optimal arrangement of all kinds of antennas to be installed on the shipboard in order to minimize the probability of EMI of equipment and subsystems in real ship after construction phase. In this paper we analyze the characteristics of electric-fields such as radiation patterns and near E-fields of V/UHF antennas installed on a shipboard. We compare simulated results with measurements on the real ship for near E-fields to verify the reliability of the computed electromagnetic environment. Although there are various factors causing errors such as cable loss and impedance mismatching etc. when measuring near E-field, both data show similar trends in the range of the acceptable tolerance.

레토르트 삼계탕의 F₀값 수준에 따른 품질 차이

이진호,송기창,이근택,Lee, Jin Ho,Song, Gi Chang,Lee, Keun Taik 한국식품저장유통학회 2016 한국식품저장유통학회지 Vol.23 No.6

국내 삼계탕 제조업체에서의 스팀식 레토르트기내 위치별 $F_0$ 분포를 조사하고 이에 따라 시료를 3가지 $F_0$값(10~20, 20~30, 및 >30) 수준으로 구분하여, 처리구별 품질 차이를 확인하였다. $F_0$값의 수준이 높아질수록 삼계탕 가슴부위육의 육수에서의 무기질 함량, 육의 $L^*$과 $b^*$ 값, 죽과 육에서의 소화율 및 육수의 탁도는 증가하는 경향을 보였고, 육에서의 유리 아미노산 함량과 가슴살과 뼈의 경도는 오히려 유의적으로 낮아지는 경향을 보였다. 전자코로 측정된 육수와 가슴살의 향기 패턴은 시료에 따라 큰 차이를 나타냈다. 관능학적 평가 결과 높은 $F_0$값으로 처리할수록 색, 이취, 조직감 및 향미 등 모든 지표 값이 낮아지는 경향이 확인되었는데, 특히 T3 시료의 색과 조직감은 T1과 T2시료에서보다 확실히 열등하게 평가되었다. 따라서 삼계탕의 품질 열화를 줄이기 위해서는 가능한 한 최소한의 $F_0$값 처리가 요구되며, 이를 위해서는 레토르트기의 우수한 성능과 효율성이 보장되고 이와 관련한 각 공장에 적합한 살균기술의 표준화가 필요할 것으로 사료된다. This study was conducted to determine the $F_0$-values of a retort machine at different locations and to evaluate the effects of these $F_0$-values on various quality characteristics of retorted Samgyetang samples. Samples were divided into three groups based on $F_0$-values-T1, 10~20; T2, 20~30; T3, >30. Mineral content in Samgyetang broth and breast meat mostly increased with increasing $F_0$-values. In general, the free amino acid values, hardness, and springiness, except for bone springiness, of Samgyetang decreased significantly at higher $F_0$-values. Protein content of meat and broth of the treated samples were significantly lower than that of the control. An increase in the digestion rate of meat and porridge, as well as the turbidity of the broth was observed in most of the treated samples with increasing $F_0$-values. With increasing $F_0$-values, the $L^*$ and $b^*$ values of meat and the $b^*$ values of broth tended to increase, while the $a^*$ value of broth increased significantly. Electronic nose analysis revealed different flavor patterns for samples treated at different $F_0$-values. For sensory traits, samples treated with higher $F_0$-values tended to receive lower evaluations. Particularly, the color and texture of T3 samples were lower than those of T1 and T2 samples. In conclusion, to improve the quality of Samgyetang, the efficiency and optimization of retort machines as well as the standardization of sterilization techniques are needed.

K-7소음총의 사격음 특성에 대한 실험적 연구

이진호,Lee Jin-Ho 한국군사과학기술학회 2004 한국군사과학기술학회지 Vol.7 No.4

In 1909 Hiram P. Maxim invented one of the first metal silencers for reducing sound levels in firearms. Silenced me have been mainly applied in the hunting and military operation. In particular special force make use of silenced rifle because it is low sound level. This paper considers experimental analysis for the characteristics of shock wave caused by shooting of a silenced me. Experimental results Indicate that the sound level of K-7 silenced rifle was lower than the sound level of MP5 silenced rifle. And, Sound Power Level of K-7 silenced rifle at a distance more than 75m or loom have nearly the constant value. This results that suggested the characteristics data about K-7 rifle's impulse noise will be apply to design the silencer of a small arms.