• Journal of the Korean Society of Marine Environment & Safety
• /
• v.24 no.6
• /
• pp.803-809
• /
• 2018

Generally, the gap-and-sag method is used in the shipbuilding stage before coupling the shafts to check whether they are installed at the same position as designed and derived from shaft alignment calculation. The primary installed propeller shaft becomes a reference point, the position of the remaining shafts are sequentially determined through the gap-and-sag value derived from the deflection and deflection angle at each shaft flange by own weight. If the reference point varies against the design value, it would have a series of effects on the installation of the remaining shafts. Moreover, after coupling the shafts, even if the bearing reaction forces derived from measurement are satisfied by the allowable limit range, consequently it might have an adverse effect on the stability of the shafting system by not being able to estimate the relative slope angle between the propeller shaft and the after-stern tube bearing. In this paper, to deal with above-mentioned phenomenon, the theoretical calculations related to designing an effective support point of the aft stern tube bearing and analysis by measurement is conducted through a case of open-up inspections. Based on this, a shaft installation guideline is proposed to minimize the misalignment related to preventing wiping damage of the after-stern tube bearing.

• Journal of the Society of Naval Architects of Korea
• /
• v.38 no.1
• /
• pp.52-61
• /
• 2001

It is necessary to obtain the well-documented local flow measurement data for the validation of CFD prediction of hydrodynamic performance. In the present paper the local flow fields around the stern region of a VLCC model with drift angles of $0^{\circ},\;5^{\circ},\;and\;10^{\circ}$ are measured. Mean velocity components are documented at St. 2 and A.P. of both port and starboard side of KVLCC in KRlSO towing tank. Flow information associated with the formation of four discrete vortices in the stern region is explored. The present experimental data can provide a good test case to validate the accuracy of numerical modeling for stern flow and maneuverability prediction of modern tanker hull forms.

• Aerospace Engineering and Technology
• /
• v.1 no.1
• /
• pp.8-27
• /
• 2002

In this study, the load analysis of a composite canard aircraft is performed numerically. Excel visual basic program for PC is used to calculate aerodynamic coefficients, loads and moments etc.. The basic data required for the load analysis such as aircraft configuration and dimension, parts and its weight and coordinate etc. are obtained from Catia modeling, measurement or material density. Aircraft weight, center of gravity, inertia moment, structural design speeds, wing load distribution, forces and moments are evaluated by using these data. V-n diagram is also represented for selecting critical loads applied to the wing and fuselage. The V-n diagram is investigated to decide the flight envelope of canard aircraft for design speed VA, VC, VD and load factor +3.8G, -1.52G at maximum weight of 2,573 lbs and sea level. In the future, the results of the wing and fuselage load analysis is to represented by using selected critical loads.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.16 no.7
• /
• pp.1391-1397
• /
• 1992

Improved power law flow model was suggested for the calculation of wake flow characteristics around the three dimensional ship stern in case of the formation of bilge vortex in the direction of stern. In comparison with the power law and Coles flow model, the flow velocity calculated based on this study was delayed around the boundary of inner layer and outer layer in reverse flow. More accurate results was obtained with this improved power law flow model by the velocity calculation around ship stern. Accuracy was validated with the comparison of other calculation results and experimental datas.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.9 no.4
• /
• pp.15-23
• /
• 2006

In this paper, full-scale airframe static test of 4-seater canard airplane(the Firefly) was explained. From the results of the structural analysis, 5 design limit loads test conditions and 11 design ultimate loads test conditions were selected. Test loads analysis was performed and test fixtures and load control system(LCS) were prepared to realize the test loads. To protect the test article during the test, the overload protection system was prepared. Strain and deflection values were acquired through the data acquisition system(DAS) to verify the structural analysis results.

• Journal of the Society of Naval Architects of Korea
• /
• v.47 no.4
• /
• pp.496-507
• /
• 2010

It is well known that when a high-speed planing craft travels in following seas it experiences long-periodic motions due to low encounter frequency, and it often loses its course keeping stability. Therefore, it is necessary to study the sea-keeping performance and stability of it in the following seas. In this paper, the vertical motions of a planing craft were measured in following regular waves, and the test results were compared with the theoretical results. In the case of the same encounter frequency, non-dimensionalized motion amplitudes become larger as Froude number is higher, and non-dimensionalized motion amplitudes in head waves are larger than those in following waves. The mean values of the motions in following waves are similar to the running attitudes of a craft in calm water at the same Froude number.

• 한국약용작물학회:학술대회논문집
• /
• 2008.11a
• /
• pp.352-353
• /
• 2008

• Proceedings of the Korean Environmental Sciences Society Conference
• /
• 2008.11a
• /
• pp.193-197
• /
• 2008

까마중과 어성초의 에탄올 추출물의 기능적 특성을 검토하고, 환원력을 기준한 항산화 활성과 아질산염 소거능을 측정하였다. 추출액의 가용성 고형분은 까마중 잎>어성초>까마중뿌리>까마중 열매의 순이었으나 TFC함량은 어성초가 가장 높고 까마중의 경우 잎>열매>뿌리의 순이었다. 한편 항산화활성은 까마중 잎>어성초>까마중 열매>까마중 뿌리의 순이었다. 아질산염 소거능은 실험 pH범위에서 까마중 잎이 어성초 보다 높았으며, 모든 추출액에 대하여 낮은 pH에서의 NSA가 더 높은 값을 보였다.

• Proceedings of the Korean Society of Fisheries Technology Conference
• /
• 2002.10a
• /
• pp.98-99
• /
• 2002

Allergy라는 말은 1906년 오스트리아의 소아과 의사인 Clemens von Pirquet가 처음 명명한 이래로 현재까지 세계적으로 널리 사용되고 있는 말이며 '이물질에 대한 신체의 잘못 변화된 능력'으로 정의되고 있다(Huby et al.,2000), Allergy를 일으키는 원인 물질을 일반적으로 allergen이라 하는데 우리 주변에 존재하는 모든 물질이 allergen으로서 작용할 수 있으며 특히 식품에 의해 유발되는 allergy를 food allergy 라고 한다(Aalberse, 2000). (중략)

• Proceedings of the Korean Society of Fisheries Technology Conference
• /
• 2000.05a
• /
• pp.114-115
• /
• 2000

키토산은 자연계에 풍부하게 존재하는 천연 고분자인 키틴을 탈아세틸화하여 얻을 수 있는 biopolymer로서 고밀도의 양전하를 띤 선형의 polyelectrolyte 구조를 이루고 있으며, 식품과 관련된 기능으로는 금속, 색소 및 고분자 물질의 흡착능, 지질 및 cholesterol흡착 배설능, 항균성, 항산화성, 항돌연변이성 등이 알려져 있다. 한편, 생활수준이 향상됨에 따라 보다 신선하며 합성 방부제가 함유되어 있지 않는 식품에 대한 소비자의 선호도가 증가함으로써 최소의 방부제로 가공된 냉장식품의 유통이 증가하고 있다. (중략)