• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2008년도 정기 학술대회
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• pp.166-171
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• 2008

LNG carrier is a special-purpose vessel to transport natural gas (NG) from the place of origin to each consuming country. To increase the capacity of canying LNG carrier, the natural gas is conveyed as a state of liquid called LNG (Liquefied Natural Gas) during a voyage because the total volume of NG is surprisingly reduced when it is cooled down to $-162^{\circ}C$. That is why the design of insulation of the carriers is important to protect LNG from the external heat invasion, and it has been a great challenging subject for several decades in the shipbuilding industry. For this ultimate goal, the boil-off rate (BOR) needs to be accurately estimated during a voyage. Therefore, the goal of this study is to propose a numerical method for estimating the BOR of LNG for given insulation containment subject to external temperature conditions during voyage.

• 대한기계학회논문집
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• 제18권4호
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• pp.986-996
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• 1994

Insulation system of LNG carrier has made important roles such as maintaining a proper Boil off Ratio(BOR) for the cargo and avoiding the excessive low temperature of the adjacent inner hull beyond the permissible limit. At the same time, safety and economy of the LNG transportation by the ship are connected with the performance of the insulation system. Also, thermal insulation system of LNG carrier is one of the most advanced technique with the structure analysis of tank, welding and assembling. In this study a computer program is developed to calculate the hull temperature distribution and BOR, which are important factors in thermal design for the Moss Rosenberg Verft spherical tank type LNG carrier. Detailed results for hhull temperature distribution close to LNG tank, BOR and the thickness effect of insulation material are reported in this paper in the range of standare design sea condition.

• Journal of Advanced Marine Engineering and Technology
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• 제32권8호
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• pp.1192-1200
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• 2008

This paper is concerned with the thermal design of the $138,000m^3$ class membrane type LNGC. To predict the temperature distribution, BOG and BOR, 3-dimensional numerical calculation was carried-out for the quarter of No.3 LNG tank. These sequence analyses were performed under the standard conditions of IMO ship design condition, USCG ship design condition and the Korean flag LNGC's route condition according to the 6-voyage modes. As the results, temperature behavior, heat flux, total penetrating heat, BOG and BOR were obtained, and those were compared with the maneuvering results considering the real temperature variation of air and sea water temperature at noon time. For securing the safety of LNGC during the ballast voyage, optimum control patterns of pressure and temperature in LNG tank is suggested in this paper.

• 한국통신학회논문지
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• 제19권2호
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• pp.225-230
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• 1994

전자장 해석을 위한 많은 수식들이 전계형 적분방정식으로 수식화되어 여러 가지 수치적인 방법으로 해석되어진다. 일반적으로 이 식은 특이점을 갖는 Kernel로 표현되어지며, 주어진 문제에 따라 식이 간략화 되어지지 않으면 해석시 수직과 프로그램이 복잡하여진다. 본 논문에서는 BOR구조의 도체에 적용할 수 있는 새로운 적분방정식을유도하였으며, 이 식은 직선형 wire도체의 경우에 더욱 간략화 되어진다. 동축선로로 급전되어지는 monopole안테나와 임의의 각도로 입사하는 평면파에 의한 도체의 산란문제를 응용예로서 다루었다.

• 대한조선학회논문집
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• 제34권4호
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• pp.108-118
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• 1997

LNG운반선은 일반 상선과는 달리 경제성 관점에서의 적정 Boil-Off Rate(BOR)과 안전성 관점에서의 Steel Grade 결정을 위한 Cargo tank 온도분포 해석이 필수적이다. Membrane형 LNG선의 경우 이미 여러가지 해석이 수행된 바 있지만 대부분이 상당히 영향을 주는 부재들의 영향을 무시하였다. 본 연구에서는 이전의 연구에 더하여 온도 분포 해석에 가장 중요한 대류 열전달 계수의 산정에 더욱 정확한 상관식을 적용하였고 Longitudinal과 Floor등 주요 부재의 영향을 충분히 고려한 3차원 온도분포 해석과 BOR을 산정하는 program을 개발하였다. 또한 여러 가지 경우에 대해 타당성을 검토한 후 그 결과를 설계에 반영하였다.

• Journal of Dental Anesthesia and Pain Medicine
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• 제17권3호
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• pp.215-217
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• 2017

Branchio-oto-renal syndrome (BOR) is a rare autosomal dominant disorder. The features include branchial cysts, hearing loss, ear malformation, preauricular pits, retrognathia, congenital heart disease, and renal abnormalities. However, anesthetic management of these patients has seldom been reported. We report a case in which general anesthesia was performed for dental treatment in a patient with BOR. Airway management, renal function, and hemodynamic changes can be of critical concern during anesthetic management. A 13-year-old girl diagnosed with BOR had severe right hearing loss, right external ear malformation, renal abnormalities, and postoperative patent ductus arteriosus (PDA). Dental extraction under general anesthesia was scheduled for a supernumerary tooth. The procedure was completed with sufficient urine volume, adequate airway management, and stable hemodynamics.

• 생명과학회지
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• 제13권5호
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• pp.692-698
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• 2003

뇌 세포막 유동성의 촉진 및 LPO생성의 억제효과는 중풍 등 뇌혈관질환을 억제할 수 있을 뿐만 아니라 혈관성치매의 예방에도 크게 기여할 것으로 기대된다[26,18]. 따라서 솔잎 EtOAc획분을 하루 25, 50, 100 mg/kg BW로써 SD계 랫트에 45일동안 투여하여 뇌조직중의 세포막 유동성 (membrane fluidity : MF), 기초 및 유도활성산소(BOR 및 IOR), 산화적 스트레스로서 과산화지질(lipid peroxide : LPO) 및 산화단백질(oxidized protein : OP), 그리고 리포푸신(lipofuscin : LF)의 축적에 미치는 영향을 평가하여 보았다. 솔잎 EtOAc획분의 투여에 의하여 뇌조직의 mitochondria 및 microsome획분에서 용량의존적으로 MF가 증가효과가 나타났지만, EtOAc-100 투여그룹의 mitochondria 획분에서만 약 10%의 유의적인 MF의 증가효과가 인정되었다. 뇌조직의 mitochondria에서 기초 및 유도활성산소로서 BOR 및 IOR의 생성은 EtOAc-50 및 EtOAc-100투여그룹에서 각각 9.2∼10.2% 및 17.1∼24.0%의 유의적인 억제효과가 인정되었고, microsomes에서 BOR 및 IOR의 생성은 EtOAc-50및 EtOAc-100투여그룹에서 각각 11.6∼16.6% 및 12.1∼16.1%의 유의적인 억제효과가 인정되었다. 산화적 스트레스에 미치는 영향은 mitochondria 및 microsomes획분에서 EtOAc-50 및 EtOAc-100투여그룹에서 각각 8.5∼12.0% 및 11.6∼18.5%의 유의적인 LPO의 생성 억제효과가 인정되었지만, 뇌조직의 두 획분에서 OP의 생성은 EtOAc획분의 용량의존적으로 억제되었지만, 유의성은 인정할 수 없었다. 또한 뇌조직에서 LF의 축적도 EtOAc획분의 용량 의존적으로 억제효과가 나타났지만, 유의성은 인정할 수 없었다. 이상의 결과에서 평가하여 볼 때 솔잎 EtOAc획분의 투여는 뇌조직의 유동성을 촉진하고 LPO의 생성을 효과적으로 억제할 수 있지만, 현재의 투여농도에서는 OP 및 LF의 생성을 방지할 수 없을 것으로 생각된다.

• 대한조선학회논문집
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• 제60권4호
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• pp.222-230
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• 2023

In the present work, the scale effect on the Boil-Off Rate (BOR) was investigated based on an analytical method to systematically evaluate the thermal performance of a Liquefied Natural Gas (LNG) Cargo Containment System (CCS). A two-dimensional thermal resistance network model was developed to accurately estimate the heat ingress into the CCS from the outside. The analysis was performed for the KC-1 LNG membrane tank under the IGC and USCG design conditions. The ballast compartment of both the LNG tank and cofferdam was divided into six sections and a thermal resistance network model was made for each section. To check the validity of the developed model, the analysis results were compared with those from existing literature. It was shown that the BOR values under the IGC and USCG design conditions were agreed well with previous numerical results with a maximum error of 1.03% and 0.60%, respectively. A SDR, the scale factor of the LNG CCS was introduced and the BOR, air temperature of the ballast compartment, and the surface temperature of the inner hull were obtained to examine the influence of the SDR on the thermal performance. Finally, a correlation for the BOR was proposed, which could be expressed as a simple formula inversely proportional to the SDR. The proposed correlation could be utilized for predicting the BOR of a full-scale LNG tank based on the BOR measurement data of lab-scale model tanks.

• 한국약용작물학회:학술대회논문집
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• 한국약용작물학회 2007년도 춘계학술발표회
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• pp.115-116
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• 2007

• 한국약용작물학회:학술대회논문집
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• 한국약용작물학회 2007년도 춘계학술발표회
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• pp.117-118
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• 2007