• Journal of Astronomy and Space Sciences
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• 제12권2호
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• pp.234-243
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• 1995

1997년 10월에 발사 예정인 과학 로켓 3호는 고도 160km까지 도달할 것이 예상되므로 한반도 상공의 전리층 E 영역에 존재하는 플라즈마를 직접 측정할 수 있는 좋은 기회를 제공한다. 한펀 플라즈마 측정에 있어서 가장 기본이 되는 검출기인 Langmuir 탑침을 실험실에서 사용하는 방법 그대로 우주 실험에 적용하면 탐침의 오염으로 인해 정확한 플라즈마 실험이 불가능해 진다. 본 논문에서는 로켓용 탑침 제작에 앞서 실험실용 탐침을 제작하여 진공 용기에서 플라즈마 실험을 수행함으로써 탐침의 오염 문제를 연구하였다. 그 결과, 플라즈마의 밀도가 낮을수록 오염에 의한 효과는 적었으며 탐침에 제공되는 쓸기전압의 주파수가 증가할수록 오염에 의한 효과를 줄일 수 있었다. 이러한 연구 결과를 바탕으로 로켓 실험에 적당한 변형된 형태의 Langmuir 탐침을 제안하였다.

• 대한수의학회지
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• 제10권2호
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• pp.1-5
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• 1970

In these studies the efficracy of plate, tube agglutination and agar-gel precipitin test were compared for the detection of pullorum infected chickens. From all the chickens showing positive reaction in agar-gel precipitin test, Salmonella pullorum organisms were isolated.

• Nuclear Engineering and Technology
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• 제54권10호
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• pp.3909-3918
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• 2022

In the event of a severe accident, the reactor core may melt due to insufficient cooling. the high-temperature core melt will have a strong interaction (FCI) with the coolant, which may lead to steam explosion. Steam explosion would pose a serious threat to the safety of the reactors. Therefore, the study of steam explosion is of great significance to the assessment of severe accidents in nuclear reactors. This research focuses on the development of a two-dimensional steam explosion integrated analysis code called SEINA. Based on the semi-implicit Euler scheme, the three-phase field was considered in this code. Besides, the influence of evaporation drag of melt and the influence of solidified shell during the process of melt droplet fragmentation were also considered. The code was simulated and validated by FARO L-14 and KROTOS KS-2 experiments. The calculation results of SEINA code are in good agreement with the experimental results, and the results show that if the effects of evaporation drag and melt solidification shell are considered, the FCI process can be described more accurately. Therefore, it is proved that SEINA has the potential to be a powerful and effective tool for the analysis of steam explosions in nuclear reactors.

• Nuclear Engineering and Technology
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• 제54권11호
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• pp.4329-4337
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• 2022

Jet impinging device is designed for decay heat removal on horizontal fuel rods in a low temperature heating reactor. An experimental system with a fuel rod simulator is established and experiments are performed to evaluate water film covering capacity, within 0.0287-0.0444 kg/ms mass flow rate, 0-164.1 kW/m² heating flux and 13.8-91.4℃ feeding water temperature. An effective method to obtain the film coverage rate by infrared equipment is proposed. Water film flowing patterns are recoded and the film coverage rates at different circumference angles are measured. It is found the film coverage rate decreases with heating flux during single-phase convection, while increases after onset of nucleate boiling. Besides, film coverage rate is found affected by Marangoni effect and film accelerating effect, and surface wetting is significantly facilitated by bubble behavior. Based on the observed phenomenon and physical mechanism, dry-out depth and initial dry-out rate are proposed to evaluate film covering potential on a heating surface. A model to predict film coverage rate is proposed based on the data. The findings would have reliable guide and important implications for further evaluation and design of decay heat removal system of new reactors, and could be helpful for passive containment cooling research.

• 한국과학교육학회지
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• 제25권3호
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• pp.346-352
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• 2005

이 연구에서는 문제 해결을 강조한 탐구적 일반화학 실험을 개발하여 그 적용 효과와 학생들의 실험에 참여하는 태도에 미치는 영향을 알아보는데 목적을 두고 있다. 문제 해결을 강조한 일반화학 실험이 실험에 참여하는 태도 변화에 효과가 있었는데, 맹목적 참여자에서 비판적 참여자로 변화한 수가 실험집단에서 3배 가까이 많았다. 또한, 차별성 인식, 탐구 정도, 토론의 유용성 부분에서 유의미한 차이를 보였다.

• 한국식품저장유통학회:학술대회논문집
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• 한국식품저장유통학회 2003년도 제23차 추계총회 및 국제학술심포지움
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• pp.46-50
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• 2003

In order to develop a new variety of rice that adapts to the climate of Aomori prefecture and possesses characteristics suitable for production of high quality Japanese sake, artificial cross experiments were executed between Yamadanishiki, which is widely used nationwide as an authentic variety of rice for sake production, and Hanafubuki, which was peviously developed by Aomori prefecture. An excellent hybrid, named Hanaomoi, was selected and fixed by a series of selection experiments and systematic cultivation. Unpolished Hanaomoi rice contained less amount of protein than Yamadanishiki and Hanafubuki. Unpolished rice of Hanaomoi was harder than Yamadanishiri and Hanafubuki, therefore polishing treatment was done in high yield and one could obtain a high degree of polish on the rice(namely 40% polishing). These features are advantageous to production of high quality of sake.Test brewing using 40% polished Hanaomoi gave rise to a characteristic sake that contained a slightly higher amount of alcohol and flavor components than Yamadanishiki and Hanafubuki. Sensory tests concluded that sake from Hanaomoi was as superior as the one from authentic Yamadanishiki. Hanaomoi is a promising variety of rice suitable for production of a high quality sake exclusive to Aomori prefecture.

• The Korean Journal of Ecology
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• 제9권1호
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• pp.33-40
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• 1986

The distribution of giant duckweed (Spirodela polyrrhiza) and small duckweed (Lemna aequinoctialis) was investigated at lead-zinc mine area and the limiting factors for their distribution were studied by laboratory experiments. The metal investigated of water affected on the growth of giant duckweed and small duckweed. Under filed conditions, both giant duckweed and small duckweed did not persist at more acidic conditions than pH 4.8 or at conditions more than 0.30 ppm of Cd concentration. Giant duckweeds were intolerable, under conditiions with less than 0.30 ppm of Cd and above than 0.07ppm of Zn, but small duckweeds were tolerable under conditions of more than 0.07 ppm of Zn concentration. However, neither can live above 7.50ppm of Zn concentration. These field observations corresponded with the results of the laboratory experiments.

• BMB Reports
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• 제42권10호
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• pp.667-672
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• 2009

Plasma concentrations of adiponectin have been shown to be decreased in patients with obesity, cardiovascular diseases, hypertension and metabolic syndrome. Recent studies have found that adiponectin reduces lipid accumulation in macrophage foam cells which may impact the development of atherosclerosis. However, it remains unclear whether adiponectin is involved in the process of lipid accumulation during myogenesis. Using C2C12 myoblasts, we investigated the effect of adiponectin on intramyocellular lipid accumulation during myogenesis. The results showed that intracellular lipid accumulation is significantly decreased during C2C12 differentiation, apparently due to increased fatty acid oxidation and decreased fatty acid synthesis during this process. C2C12 cells transiently transfected with adiponectin gene showed reduced lipid accumulation as compared to controls. Further experiments demonstrated that adiponectin can suppress lipid accumulation by increasing fatty acid oxidation during C2C12 myogenesis.

• BMB Reports
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• 제37권4호
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• pp.402-407
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• 2004

A human gene T-complex protein 10 like (TCP10L) was cloned in our lab. A previous study showed that it expressed specifically in the liver and testis. A transcription experiment revealed that TCP10L was a transcription factor with transcription inhibition activity. In this study, the human MAD4 was identified to interact with TCP10L by a yeast two-hybrid screen. This finding was confirmed by immunoprecipitation and subcellular localization experiments. As MAD4 is a member of the MAD family, which antagonizes the functions of MYC and promotes cell differentiation, the biological function of the interaction between TCP10L and MAD4 may be to maintain the differentiation state in liver cells. Also, we propose that the up-regulation of Myc is caused by the down-regulation of TCP10L in human hepatocarcinomas.

• Smart Structures and Systems
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• 제32권4호
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• pp.207-218
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• 2023

Real-time monitoring of the behavior of reinforced soil retaining wall (RSW) is required for safety checks. In this study, a targetless displacement measurement technology (TDMT) consisting of an image registration module and a displacement calculation module was proposed to monitor the behavior of RSW, in which facing displacement and settlement typically occur. Laboratory and field experiments were conducted to compare the measuring performance of natural target (NT) with the performance of artificial target (AT). Feature count- and location-based performance metrics and displacement calculation performance were analyzed to determine their correlations. The results of laboratory and field experiments showed that the feature location-based performance metric was more relevant to the displacement calculation performance than the feature count-based performance metric. The mean relative errors of the TDMT were less than 1.69 % and 5.50 % for the laboratory and field experiments, respectively. The proposed TDMT can accurately monitor the behavior of RSW for real-time safety checks.