• 현장농수산연구지
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• 제22권1호
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• pp.79-85
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• 2020

이 연구는 최초의 국내 말에서 수동면역부전을 다룬 것이다. 이 연구의 목적은 건강한 말과 아픈 말의 면역상태를 비교하는 것이다. 수동면역부전은 말에서 가장 흔한 면역결핍질환이다. 아픈말 22 마리와 건강한 말 18 마리를 검사키트(SNAP Foal IgG Test Kit)를 이용하여 수동면역부전을 진단하였다. 모든 성마는 정상적인 면역기능을 가지고 있었다(≥800 mg/㎗). 신생망아지는 22 마리 중 13 마리(59%; ∠800 mg/㎗)가 면역기능이 취약하였지만 치료 후 회복하여 생존하였다. 이 22 마리 중 9 마리는 면역기능이 강한 말(≥ 800 mg/㎗)로 혈중 IgG농도가 높아도 감염성 질환이 발생할 수 있다는 것을 보여준다. 폐사망아지는 모두 6 마리였고, 그중 4 마리는 감염성 질환이었다. 신생망아지 면역상태 검사를 통한 감염취약 정도의 조기진단 및 대응방안 마련으로 경주자원 활용율 제고와 보건관리 기술향상을 도모할 수 있다. 또한, 신생망아지의 감염성질환 조기 파악으로 향후 육성마의 체계적인 보건관리방안 마련에 일조할 수 있을 것으로 기대된다.

• 한국지반공학회지:지반
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• 제12권6호
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• pp.21-36
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• 1996

흙과 Geogrid사이의 응력 전달은 마찰저항 및 수동저항으로 나눌 수 있는데 Geogrid의 횡방향 요소에 작용하는 수동저항은 그 메카니즘이 복잡하여 아직까지 거동이 명확하게 파악되지 못하고 있다. 이러한 수동저항의 메카니즘을 이해하기 위하여 돌기가 있는 보강재에 대한 직접 전단시험을 유한 요소 방법으로 해석하였다. 유한 요소해석으로 돌기의 간격에 따라 수동저항의 크기, 파괴형태, 응력 및 변형 분포 등을 분석하였으며 일 결과들을 실제 계측치와 비교 분석하여 Geogrid의 횡방향 요소에 작용하는 보강재의 수동저항의 거동을 파악하도록 하였다. 또한 흙의 종류에 따라 수동저항의 메카니즘을 파악하기 위해 점성토에 작용하는 수동저항의 거동을 예측하였다.

• 한국동물위생학회지
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• 제31권4호
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• pp.533-546
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• 2008

The efficacy of bovine immune sera to correct the calves with failure of passive transfer(FPT) was evaluated. Immune sera were produced from 14 one-year-old Holstein cattle which were inoculated commercial combined viral vaccine, administered by the challenge of some main enteric or respiratory viruses, aseptically filtered and stored at $4^{\circ}C$ before used. After the treatment of bovine immune sera, Mean transfer factor($mg/d{\ell}$, of IgG administered/kg of body weight) was $5.46{\pm}2.74,\;11.17{\pm}1.27,\;1.40{\pm}0.21$ in K-IP, H-IP and K-IV group, respectively. The corrective effect of bovine immune sera to FPT calf without any clinical signs showed that intravenous route was more effective than intraperitoneal administration(P<0.01). FPT calves with severe signs were not effective response to the immunotherapy used and consequently died within 10 days after the treatment. Ten percentage of controls appeared the clinical signs including diarrhea. On the contrary, there were not any clinical signs in K-IP and H-IV group. There was significant increase of the neutralizing titer against bovine viral diarrhea virus and bovine coronavirus as well as of cell population including CD2, CD4, and monocyte in K-IP and H-IV group after the immunotherapy(P<0.05). Also, K-IP and H-IV group showed the successful correction to FPT within one week after the immunotherapy, but controls had kept the FPT two-four weeks even after the same treatment. Consequently, the results were suggesting that the bovine immune sera could be used the corrective tool to young calves with FPT.

• 한국동물위생학회지
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• 제31권4호
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• pp.505-519
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• 2008

For screening the appropriate field diagnostic techniques to failure of passive immunoglobulin transfer(FPT) in Korean-indigenous calves, 258 sera was examined by spectinophotometry for total protein(TP) and globulin(Glo), sodium sulfate precipitation test(SSPT), zinc sulfate turbidity test(ZSTT), and single radial immunodiffusion test(sRID). All calves aged within 6-week old. Morbidity and mortality to various diseases, mainly including enteric and respiratory disorders, were 18.9%(49) and 4.2%(11), respectively. FPT was 27,9%(72/258) when the cutoff point of TP was $4.5g/d{\ell}$ and among them the morbidity and mortality were 27.9% and 6.9%, respectively. FPT was 29.1%(75/258) when the cutoff point of Glo was $2.0g/d{\ell}$ and among them the morbidity and mortality were 29.0% and 6.9%, respectively. FPT was 13.1%(34/258) when the cutoff point of SSPT was 1+ and among them the morbidity and mortality were 67.6% and 23.5%, respectively. FPT was 19.7%(51/258) when the cutoff point of IgG with sRID was $1,000mg/d{\ell}$ and among them the morbidity and mortality were 41.1% and 11.7%, respectively. In addition, mean concentration of IgG with sRID tested was $2,150mg/d{\ell}$ at 3-day old but $1,100mg/d{\ell}$ at 9-days with $1,100mg/d{\ell}$. The results of the study were suggested that SSPT for FPT was the relatively reliable and convinient method for evaluating the immune status of calves(P<0.05).

• International Journal of Naval Architecture and Ocean Engineering
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• 제6권4호
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• pp.826-839
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• 2014

Fire is a continuous threat to FPSO topside modules as large amounts of oil and gas are passing through the modules. As a conventional measure to mitigate structural failure under fire, passive fire protection (PFP) coatings are widely used on main structural members. However, an excessive use of PFP coatings can cause considerable cost for material purchase, installation, inspection and maintenance. Long installation time can be a risk since the work should be done nearly at the last fabrication stage. Thus, the minimal use of PFP can be beneficial to the reduction of construction cost and the avoidance of schedule delay. This paper presents a few case studies on how different applications of PFP have influence on collapse time of a FPSO module structure. A series of heat analysis and thermal elasto-plastic FE analysis are performed for different PFP coatings and the resultant collapse time and the amount of PFP coatings are compared with each other.

• 한국전산유체공학회지
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• 제15권1호
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• pp.1-8
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• 2010

RCCS is a passive safety-related system that removes the decay heat of VHTR when normal decay heat removal systems are in failure. Understanding thermo-hydraulics of RCCS is important to design a safer VHTR. RCCS consists of 292 cooling panels, which are placed in the reactor cavity. The layout of RCCS gives an idea that, for CFD simulations, cooling panels can be assumed to be one annulus tube. This assumption can reduce significantly the computational time, especially for the unsteady simulation. To simulate RCCS in an axisymmetric manner, three models were suggested and compared. Each model has (1) the same outer radius, (2) the same cross-sectional area (3) the same pressure drop, respectively, as the RCCS cooling panels. The steady-state simulation was conducted with these three models and the DO radiation model. It is found that over 90% of the heat from the outer wall of the reactor pressure vessel is transported to the RCCS by radiative heat transfer. The simulation with the third model, which has the same pressure drop as the design, estimates the closest wall temperature profiles to a thermo-hydraulic code, GAMMA+, result.

• Nuclear Engineering and Technology
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• 제55권8호
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• pp.3017-3029
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• 2023

In the late in-vessel phase of a nuclear reactor severe accident, the internal heat transfer and crust evolution during the debris bed melting process have important effects on the thermal load distribution along the vessel wall, and further affect the reactor pressure vessel (RPV) failure mode and the state of melt during leakage. This study coupled the phase change model and large eddy simulation to investigate the variations of the temperature, melt liquid fraction, crust and heat flux distributions during the debris bed melting process in the hypothetical severe accident of HPR1000. The results indicated that the heat flow towards the vessel wall and upper surface were similar at the beginning stage of debris melting, but the upward heat flow increased significantly as the development of the molten pool. The maximum heat flux towards the vessel wall reached 0.4 MW/m². The thickness of lower crust decreased as the debris melting. It was much thicker at the bottom region with the azimuthal angle below 20° and decreased rapidly at the azimuthal angle around 20-50°. The maximum and minimum thicknesses were 2 and 90 mm, respectively. By contrast, the distribution of upper crust was uniform and reached stable state much earlier than the lower crust, with the thickness of about 10 mm. Moreover, the sensitivity analysis of initial condition indicated that as the decrease of time interval from reactor scram to debris bed dried-out, the maximum debris temperature and melt fraction became larger, the lower crust thickness became thinner, but the upper crust had no significant change. The sensitivity analysis of in-vessel retention (IVR) strategies indicated that the passive and active external reactor vessel cooling (ERVC) had little effect on the internal heat transfer and crust evolution. In the case not considering the internal reactor vessel cooling (IRVC), the upper crust was not obvious.

• 한국해양공학회지
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• 제34권2호
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• pp.110-119
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• 2020

Explosions and fires on offshore drilling units and process plants, which cause loss of life and environmental damage, have been studied extensively. However, research on drilling units increased only after the 2010 Deepwater Horizon accident in the Gulf of Mexico. A major reason for explosions and fires on a drilling unit is blowout, which is caused by a failure to control the high temperatures and pressures upstream of the offshore underwater well. The area susceptible to explosion and fire due to blowout is the drill floor, which supports the main drilling system. Structural instability and collapse of the drill floor can threaten the structural integrity of the entire unit. This study simulates the behavior of fire subsequent to blowout and assesses the thermal load. A heat transfer structure analysis of the drill floor was carried out using the assessed thermal load, and the risk was noted. In order to maintain the structural integrity of the drill floor, passive fire protection of certain areas was recommended.

• Journal of Animal Science and Technology
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• 제63권5호
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• pp.1114-1125
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• 2021

Supplying a sufficient amount of high-quality colostrum is a prevailing challenge in Hanwoo calf production systems. This study aimed to describe the efficiency of a lacteal-derived colostrum replacer versus natural bovine colostrum (from Holstein) fed to Hanwoo calves. Forty newborn Hanwoo calves (25 males and 15 females; 30.7 ± 3.15 kg body weight [mean ± standard deviation]) were blocked by sex and birth weight and fed either natural colostrum or a commercial colostrum replacer. Calves displayed a narrow difference in the evolution of body weight and structural body dimensions when they received a commercial versus natural colostrum. Minor differences existed in the starter and total dry matter consumption between calves fed natural or commercial colostrum. Although the colostrum source had no significant effects on days to first diarrhea (average of 7.6 days; p = 0.17), the duration of diarrhea was longer in natural colostrum-fed calves (3.2 vs. 4.5 days; p = 0.04). Consumption of natural colostrum resulted in greater mean serum immunoglobulin G (IgG) on day 2 (14.7 vs. 10.8 ± 0.92 mg/mL) and day 7 (8.21 vs. 5.12 ± 0.82 mg/mL) of calf life, resulting in a greater proportion of commercial colostrum-fed calves (50% vs. 15%; day 2) to experience failure of passive transfer of immunity (serum IgG < cutoff point of 10 mg/mL). Overall, growth rate, body frame development, and incidence of diarrheal disease were not different in both groups. These results suggested that the colostrum replacer product tested in this study could be an alternative to natural colostrum derived from Holstein cow in securing calf growth and health in Hanwoo calf-rearing operations.