• Journal of the Society of Naval Architects of Korea
• /
• v.38 no.1
• /
• pp.72-85
• /
• 2001

A study for the structural strength evaluation on the doubler plate subjected to the biaxial in-plane compression has been performed through the systematic evaluation process. In order to estimate the proper static strength of doubler plate, elasto-plastic large deflection analysis is introduced including the contact effect between main plate and doubler. The characteristics of stiffness and strength variation are discussed based on their results. A1so, in order to compare the doubler structure with the original strength of main plate without doubler, a simple formula for the evaluation of the equivalent flat plate thickness is derived based on the additional series analysis of flat plate structure. Using this derived equation, the thickness change of a equivalent flat plate is analyzed according to the variation of various design parameters of doubler plate and some design guides are suggested in order to maintain the original strength of main plate without doubler reinforcement. Finally, correlation between derived equivalent flat plate formula and the developed buckling strength formulas by author et a1. is discovered and these relations are formulated for the future development of simple strength evaluation formula of doubler plate structure.

• Journal of the Society of Naval Architects of Korea
• /
• v.37 no.4
• /
• pp.92-105
• /
• 2000

A study for the structural strength evaluation on the slender doubler plate has been performed through the systematic evaluation process. In order to estimate the proper static strength of doubler plate subjected to the longitudinal in-plane compression, elasto-plastic large deflection analysis is introduced including the contact effect between main plate and doubler. The characteristics of stiffness and strength variation are discussed based on their results. Also, in order to compare the doubler structure with the original strength of main plate without doubler, a simple formula for the evaluation of the equivalent flat plate thickness is derived based on the additional series analysis of flat plate structure. Using this derived equation, the thickness change of a equivalent flat plate is analyzed according to the variation of various design parameters of doubler plate and some design guides are suggested in order to maintain the original strength of main plate without doubler reinforcement. Finally, correlation between derived equivalent flat plate formula and the developed buckling strength formulas by author et al. is discovered and these relations are formulated for the future development of simple strength evaluation formula of doubler plate structure.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2002.11a
• /
• pp.751-754
• /
• 2002

본 논문에서는 획득한 차량 영상에서, 차량 번호판의 후보영역을 동적으로 할당하여 번호판을 추출하고, 이중 템플릿 매칭을 이용하여 인식하는 방법을 제안하였다. 차량 번호판 영역은 다른 영역에 비해 영상의 밀도값이 높다는 것을 근거로, 후보영역을 투영하여 추출된 영상의 밀도값과 기준밀도값을 비교하여 차이가 임계값 이하를 만족한 때 차량 번호판 영역으로 추출하고 만족하지 않을 때는 다음 후보영역을 투영하여 차량 번호판 영역을 추출하였다. 추출된 번호판 영역에서 문자와 숫자영역으로 분할된 입럭패턴과 표준패턴을 흑화소로 1차 매칭하고, 이 중 유사도가 높은 표준패턴과 다시 백화소로 2차 매칭하는 이중 템플릿 매칭으로 인식하였다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2011.11a
• /
• pp.666-669
• /
• 2011

The rupture disc shapes of bulkhead type pulse separation device(PSD) are designed for new dual pulse rocket motor. Before final design PSD, that three different rupture disc are tested and confirmed the performance of the discs. Through analyzing the test results the PSD decides, two rupture disc shapes with flow holes of eight circles and eight trapezoids.

• The Journal of the Acoustical Society of Korea
• /
• v.35 no.4
• /
• pp.253-260
• /
• 2016

In this paper, derivation of the STL (Sound Transmission Loss) of the double plates installed in an impedance tube is discussed using an analytic method, where an air cavity exists between the plates. Vibration of the plates and sound pressure field inside the tube are expressed in terms of infinite series of modal functions. Under the plane wave assumption, it is shown that consideration of the first few modes yields sufficiently accurate results, and locations of peaks and dips are investigated. It is determined that the peak frequencies of the double plates coincide with those of each single plate. When the two plates are identical, the STL of the double plates as well as that of the single plate become zero at the natural frequencies of the single plate. The location and amplitude of the dips are investigated using an approximation solution when the cavity depth is very small.

• Journal of the Society of Naval Architects of Korea
• /
• v.55 no.6
• /
• pp.521-526
• /
• 2018

The doubler plate design system for the reinforcement of the ship plate members was developed considering various loads that subjected to the in-plane biaxial load, the in-plane shear load and out-of-plane load. The author summarized the accuracy of the development formula and equations through the equivalent plate thickness concept and finally introduced the new design system of doubler plate reinforcement. Through this study, it can be considered as an initial design guideline based on ship doubler plate reinforcement strength at areas without repeated load, or an initial structure analysis model for final structural design.

• Journal of KSNVE
• /
• v.7 no.6
• /
• pp.945-952
• /
• 1997

This paper shows the feasibility of the suggestion that the angle distribution of incident sound to panels might be gaussian, instead of the conventional uniform distribution in the analysis of transmission loss of panels. To prove the suggestion, the problems with the diffuse sound field in a reverberation room are examined by case studies and the comparision of the prediction with the measurement of sound transmission loss of walls are performed. The results of the comparision show good agreement between the two values.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.14 no.5
• /
• pp.101-110
• /
• 2010

Dual pulse rocket motor is a solid motor with two grains separated by a bulkhead and rupture disc. The elasto-plastic explicit dynamic analysis for the rupture disc was conducted by finite element method. The effect of the slit geometry of a rupture disc was parametrically analyzed in terms of rupture time and shape. The results can be used to control the rupture pressure by changing the slit geometry of rupture disc.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2010.05a
• /
• pp.105-112
• /
• 2010

Dual Pulse Rocket Motor is a solid rocket motor with two grains separated by a bulkhead and rupture disc. The elasto-plastic explicit dynamic analysis of rupture disc was conducted by finite element method. The effect of the slit geometry of a rupture disc was analyzed for rupture time and shape by the parametric study. The results can be used to control the rupture pressure by the change the slit geometry of a rupture disc.

• Geophysics and Geophysical Exploration
• /
• v.27 no.1
• /
• pp.51-56
• /
• 2024

In this paper, the vector gravity and gravity gradient tensor of an elliptical disk are derived. The vector gravity of an elliptical disk is defined by differentiating the gravitational potential due to the elliptical disk expressed by a double integral with respect to each axial direction. The vector gravity defined by the double integral is then transformed into a line integral of a closed curve along the elliptical disk boundary using the complex Green's theorem. Finally, vector gravity due to the elliptical disk is derived by 1D parametric numerical integration along the elliptical disk boundary. The xz, yz, zz components of the gravity gradient tensor due to the elliptical disk are obtained by differentiating the vector gravity with respect to vertical direction. The xx, yy, xy components are derived by differentiating the horizontal components of the vector gravity in the form of a double integral with respect to horizontal directions and then using the complex Green's theorem.