• 대한의생명과학회지
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• 제10권1호
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• pp.9-13
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• 2004

We have investigated the effects of hypha-water extracts (HWE), fruit body-water extracts (FWE) and cordycepin from Cordyceps militaris on serotonin release out of human platelets and human platelet aggregation. HWE and FWE inhibited the release of [$^3H$]-serotonin from human platelet stimulated by thrombin (2 U/ml) or collagen (20$\mu$g/ml) in a dose-dependent manner. Furthermore, cordycepin, a major component of Cordyceps militaris, inhibited the human platelet aggregation induced by collagen (10$\mu$g/ml) in a dose-dependent manner. These results suggest that cordycepin containing in HWE and FWE may inhibit the serotonin release by suppressing the collagen-induced human platelet aggregation. Accordingly, our data demonstrate that HWE and FWE containing much cordycepin might have antithrombotic and antimigrainous functions.

• 한국농공학회지
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• 제33권4호
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• pp.52-60
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• 1991

This study was conducted to investigate the appropriate operation method minimizing the deviation between irrigation water demand and release from the reservoirs, and the simulation technique was used in the operation model. This model was applied to the grouped reservoirs system consisted of Dongsang, Daia and Keungchun reservoirs and Eowoo-weir in Chonbuk FLIA district. The results obtained in this study are summarized as follows; 1.The area above the Eowoo weir point was divided into 6 small watersheds, and daily inflows from each watershed were calculated by Tank model. It showed that the average annual runoff ratio was 40-60% respectively. 2.Based on the Blaney-Criddle formula daily water requirement of Chonbuk FLIA irrigation area was estimated, mean water requirement for paddy field during the irrigation period was 818.lmm. 3.Using the basic data such as inflow and water demand, four different release types were selected. Through the simulated operation the difference between intake water required at Eowoo-weir point and release from the 3 reservoirs was estimated. The best result was obtained when Daia and Keungchun reservoirs are operated parallelly at fixed release ratio and the release of Dongsang reservoir was determined according to the storage of Daia reservoir.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2002년도 Proceedings of the International Welding/Joining Conference-Korea
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• pp.372-377
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• 2002

Residual stress by welding should be reduced because that decreases the reliability on strength of welded structure. The reason is that the total stiffness of structure decreases by non-linear behavior of weldment under external load. The release of residual stress by mechanical loading and unloading is often performed in the fabrication of box structure for steel bridge. The proper degree of loading and unloading is significant at release method of residual stress by mechanical loading because that degree is changed by material and geometric shape of welded structure. Therefore, the simulation model that could exactly analyze the release of residual stress by mechanical loading is to be necessary. This simulation model should be established on the based of variable and accurate measurement data. In this study, the non-linear behavior of weldments under external loading and unloading, such as the decrease and increase of structure stiffness, was investigated by monitoring of nominal stress and strain. Tensile loading and unloading test under variable load was performed and the proper degree of stress relaxation was measured by sectioning technique using strain gauge.

• International Journal of Korean Welding Society
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• 제2권1호
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• pp.40-44
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• 2002

Residual stress by welding should be reduced because that decreases the reliability on strength of welded structure. The reason is that the total stiffness of structure decreases by non-linear behavior of weldment under external load. The release of residual stress by mechanical loading and unloading is often performed in the fabrication of box structure for steel bridge. The proper degree of loading and unloading is significant at release method of residual stress by mechanical loading because that degree is changed by material and geometric shape of welded structure. Therefore, the simulation model that could exactly analyze the release of residual stress by mechanical loading is to be necessary. This simulation model should be established on the based of variable and accurate measurement data. In this study, the non-linear behavior of weldments under external loading and unloading, such as the decrease and increase of structure stiffness, was investigated by monitoring of nominal stress and strain. Tensile loading and unloading test under variable load was performed and the proper degree of stress relaxation was measured by sectioning technique using strain gauge.

• 방사성폐기물학회지
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• 제20권2호
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• pp.231-241
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• 2022

Several countries, including Korea, are considering the direct disposal of spent nuclear fuels. The radiological safety assessment results published after a geological repository closure indicate that the instant release is the main radiation source rather than the congruent release. Three Safety Case reports recently published were reviewed and the IRF values of seven long-lived radionuclides, including relevant experimental results, were compared. According to the literature review, the IRF values of both the CANDU and low burnup PWR spent fuel have been experimentally measured and used reasonably. In particular, the IRF values of volatile long-lived nuclides, such as ¹²⁹I and ¹³⁵Cs, were estimated from the FGR value. Because experimental leaching data regarding high burnup spent nuclear fuels are extremely scarce, a mathematical modelling approach proposed by Johnson and McGinnes was successfully applied to the domestic high burnup PWR spent nuclear fuel to derive the IRF values of iodine and cesium. The best estimate of the IRF was 5.5% at a discharge burnup of 55 GWd tHM^-1.

• Nuclear Engineering and Technology
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• 제55권8호
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• pp.2977-2983
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• 2023

During normal operation, some parts of the fission product in the defective fuel rods can release into the primary loops in PWR and the escape rate coefficients are widely used to assess quantitatively the release behaviors of fission products in the industry. The escape rate coefficients have been standardized and have been validated by some drilling experiments before the 1970s. In the paper, the model to determine the escape rate coefficients of fission products has been established and the typical escape rate coefficients of noble gas and iodine have been deduced based on the measured radiochemical data in one operating PWR. The result shows that the apparent escape rate coefficients vary with the release-to-birth and decay constants for different fission products of the same element. In addition, it is found that the escape rate coefficients from the defective rod with large defects are much higher than the standard escape rate coefficients, i.e., averagely 4.4 times and 1.8 times for noble gas and iodine respectively. The enhanced release of fission products from the severe secondary hydriding of several defective fuel rods in one cycle may lead to the potential risk of the temporary shutdown of the operating reactors.

• 한국컴퓨터정보학회논문지
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• 제14권7호
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• pp.1-8
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• 2009

본 연구에서는 소프트웨어 제품을 개발하여 테스팅을 거친 후 사용자에게 인도하는 시기를 결정하는 방출문제에 대하여 연구하였다. 따라서 최적 소프트웨어 방출 정책은 소프트웨어 요구 신뢰도를 만족시키고 소프트웨어 개발 및 유지 총비용을 최소화 시키는 정책을 수용해야 한다. 본 논문에서는 로그포아송 실행시간모형에 대하여 베이지안 모수 추정법(마코브체인 몬테칼로(MCMC) 기법 중에 하나인 깁스 샘플링과 메트로폴리스 알고리즘을 이용한 근사기법)이 사용되었다. 본 논문의 수치적인 예에서는 Musa의 T1 자료를 적용하여 최우수추정법과 베이지안 모수 추정과의 관계를 빅교하고 또한 최적 방출시기를 추정하였다.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2004년도 학술논문집
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• pp.368-376
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• 2004

영광부지의 추적자 확산실험결과의 자료동화를 통하여 Gaussian plume 모형의 확산인자의 수정과 추적자 방출률 평가를 수행하였다. 부지 주변의 여러 지점에서 관측한 실험결과에 선형계획법을 적용하여 확산평가에 있어선 가장 불확실성이 크다고 알려진 확산인자를 수정하였다. 원자력 비상시 초기 대응평가에 사용되는 정보 가운데 가장 큰 불확실성을 포함한 선원항 정보를 추적자 농도 분포로부터 추정하였다. 실험 당시의 추적자 방출량을 모른다고 가정하고 Gaussina plume 모형의 예측치와 확산실험의 실측치를 이용한 최소자승법을 적용하여 방출률을 추정하였다. 확산인자를 수정한 후 Gaussian plume 모형의 예측력은 방출점으로 3km 및 8km 떨어진 포집선 두 경우 모두 증가하는 것으로 나타났다. 실험당시의 방출률을 모른다고 가정하고 관측지점의 농도에 최소자승법을 적용한 결과 24%이내에서 실제 방출률을 양호하게 추정하고 있음을 확인할 수 있었다.

• The Korean Journal of Physiology and Pharmacology
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• 제18권3호
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• pp.241-247
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• 2014

To investigate the underlying mechanisms of C18 fatty acids (stearic acid, oleic acid, linoleic acid and ${\alpha}$-linolenic acid) on mast cells, we measured the effect of C18 fatty acids on intracellular $Ca^{2+}$ mobilization and histamine release in RBL-2H3 mast cells. Stearic acid rapidly increased initial peak of intracellular $Ca^{2+}$ mobilization, whereas linoleic acid and ${\alpha}$-linolenic acid gradually increased this mobilization. In the absence of extracellular $Ca^{2+}$, stearic acid ($100{\mu}M$) did not cause any increase of intracellular $Ca^{2+}$ mobilization. Both linoleic acid and ${\alpha}$-linolenic acid increased intracellular $Ca^{2+}$ mobilization, but the increase was smaller than that in the presence of extracellular $Ca^{2+}$. These results suggest that C18 fatty acid-induced intracellular $Ca^{2+}$ mobilization is mainly dependent on extracellular $Ca^{2+}$ influx. Verapamil dose-dependently inhibited stearic acid-induced intracellular $Ca^{2+}$ mobilization, but did not affect both linoleic acid- and ${\alpha}$-linolenic acid-induced intracellular $Ca^{2+}$ mobilization. These data suggest that the underlying mechanism of stearic acid, linoleic acid and ${\alpha}$-linolenic acid on intracellular $Ca^{2+}$ mobilization may differ. Linoleic acid and ${\alpha}$-linolenic acid significantly increased histamine release. Linoleic acid (C18:2: ${\omega}$-6)-induced intracellular $Ca^{2+}$ mobilization and histamine release were more prominent than ${\alpha}$-linolenic acid (C18:3: ${\omega}$-3). These data support the view that the intake of more ${\alpha}$-linolenic acid than linoleic acid is useful in preventing inflammation.

• 한국동물위생학회지
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• 제42권4호
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• pp.285-288
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• 2019

Foot-and-mouth disease (FMD) causes economic problems in livestock industry because of fast spread and inducing low productivity. FMD outbreaks occurred in South Korea over the period from 2000 to 2019. Vaccination is the most practical and effective means of controlling or preventing these outbreaks, and a national vaccination policy has been in place for all FMD-susceptible animals since 2010. To prevent and control of FMD, South Korea has been using vaccines imported from the United Kingdom, Argentina, and Russia. The Animal and Plant Quarantine Agency of South Korea oversees continuous quality control of imported FMD vaccines. FMD vaccines were evaluated characteristics, sterility, pH, inactivation, safety, potency test by Korean FMD vaccine standard assay (Test for National Lot Release). The 6 company vaccines (A~F) were used Test for National Lot Release by each method. We evaluated quality of each FMD vaccine from 2015 to 2019. All batch of vaccine showed good quality control and were passed the Test for National Lot Release. The serotypes of vaccine are increasingly changing to multiple vaccine because the FMD was outbreak by various serotype virus in South Korea. Furthermore, this data may be useful as a basis for ensuring the quality of FMD vaccines and for base data to manage them. Additional study is required to simple approach for rapid evaluation of quality and antigen content identification in vaccines.