• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 학술대회 논문집 정보 및 제어부문
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• pp.35-37
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• 2005

In this study, a P- and T-wave detection algorithm in ECG, obtained by minimized filtering to prevent waveform distortion, has been realized. The algorithm uses two slope tracing waves, the descending slope tracing wave and the ascending slope tracing wave, developed for efficient determination of slope inverting points and sudden slope changing points. The algorithm generates the slope tracing waves which trace the original ECG wave, and subtracts one tracing wave from the other to detect P- and T-waves. The algorithm has been applied to MIT/BIH database in order to verify its efficacy and validity in practical applications.

• Journal of the Korean Wood Science and Technology
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• 제31권3호
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• pp.35-41
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• 2003

The mechanical and physical properties of wood are strongly dependent upon the slope of grain. Specially, tensile strength is more severely affected by the slope of grain. Therefore, tension tests were performed on small thin wood samples made from Pinus radiata with varying the slope of grain. Determining the tensile strength for clear thin wood samples the other variabilities associated with material, size, drying, defects, etc were discarded. Slope of grain was measured by the slope of grain indicator and actual slope of grain was also determined by a protractor. Correlation coefficients between machine measured and actual slope of grain for 40 pieces of 2×20 mm, 300 mm long Pinus radiata were 0.84 for wide face measurement. Results also showed that tensile strength and MOE from stress wave tests decreased with increasing the slope of grain. This study did not establish a relationships for tensile strength and MOE from stress wave with slope of grain. However, the trends of MOEs from stress wave test with both slope of grain are agreed well with Hankinson's equation. Predicted tension strength curve by Hankinson's equation was also agreed well with the experimental data over the range from 0 to 13 degrees for slope of grain.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2006년도 Asia Navigation Conference
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• pp.95-104
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• 2006

A floating-type wave power pump is a device which sends air into water by using wave power. The floating-type wave power pump has the new configuration composed of a curved surface reflection board, a slope, and phase plates. As a result of a water-tank experiment it turned out that the floating-type wave power pump with a curved surface reflection board and a slope raised power and efficiency in the wide wavelength waves. The result of a marine experiment was also preferable. The floating-type wave power pump sends air into the sea by using wave power, so it can be used for the improvement of marine environment. In addition, the floating body constituted of a curved surface reflection board, a slope, and phase plates, is effective as a device to utilize the energy of a wave. Therefore, it can be widely used for a wave power generation, pumping up deep seawater.

• 한국정보전자통신기술학회논문지
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• 제4권1호
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• pp.17-22
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• 2011

본 연구에서는 부정맥 판독을 위해 심전도 신호로부터 P파의 강조 및 검출 방법을 제안하였다. 이 방법에서는 고전적인 필터나 이동평균필터를 사용하지 않고 하강 기울기의 변곡점을 검출하기에 효과적인 하강 기울기 추적파를 이용하여 고주파 잡음을 무시해 주는 필터 용도로 사용함과 동시에 진폭이 낮고 불명확한 P파와 T파를 강조해 줌으로써 이들의 검출을 용이하게 하였다. 이 강조 및 검출 방법을 MIT/BIH 데이터에 적용하여 구현하였으며 그 실용성을 확인하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 심포지엄 논문집 정보 및 제어부문
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• pp.48-50
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• 2006

In this paper, we propose a method to minimize the baseline wandering that make hard to detect R wave in ECG. This method uses a different signal between ECG and ascending slope tracing waves to minimize the baseline wandering. When the slope of ECG signal maintains the value or falls, the ascending slope tracing wave fellows ECG signal directly, and this wave holds that value of ECG signal when the slope begins to rises in a certain time(=hold time). After this hold time, this wave traces ECG signal again. To evaluate this minimizing method for baseline wandering, the experiments are carried out with 5 ECG data in the database of MIT/BIH. R waves in the proposed different signal are detected by using descending slope trace waves and compared with the annotation file. The results show that the proposed method Is sure to minimize the baseline wandering in ECG.

• 한국해양공학회지
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• 제18권4호
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• pp.40-45
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• 2004

An efficient numerical model of the modified mild slope equation, based on the robust iterative method is presented. The model developed is verified against other numerical experimental results, related to wave reflection from an arc-shaped bar and wave transformation over a circular shoal. The results show that the modified mild slope equation model is capable of producing accurate results for wave propagation in a region where water depth varies substantially, while the conventional mild slope equation model yeilds large errors, as the mild slope assumption is violated.

• 한국연안방재학회지
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• 제1권1호
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• pp.1-9
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• 2014

In order to examine the characteristics of tsunami run-up heights on impermeable/permeable slope, a numerical wave tank by upgrading LES-WASS-3D was used in this study. Then, the model were compared with existing hydraulic model test for its verification. The numerical results well reproduced experimental results of solitary wave deformation, propagation and run-up height under various conditions. Also, the numerical simulation with a slope boundary condition has been carried out to understand solitary wave run-up on impermeable/permeable slope. It is shown that the run-up heights on permeable slope is 52.64-63.2% smaller than those on the impermeable slope because of wave energy dissipation inside the porous media. In addition, it is revealed that the numerical results with slope boundary condition agreed well with experimental results in comparison with the results by using stair type boundary condition.

• 한국해양공학회지
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• 제38권5호
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• pp.218-231
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• 2024

In harsh environments, an floating production storage and offloading (FPSO) is occasionally damaged by impact loads, such as bow flare slamming and green water. This study conducted an impact load measurement experiment on a model of an FPSO bow in a 2D wave tank. Three types of frequency-focused waves (steep, spilling, and plunging) were generated, and the speed and slope of the waves were measured. Seven wave probes were placed in a row, and the wave elevation was measured to determine the speed and slope of the waves. In addition, the side of the 2D wave tank was photographed with a high-speed camera. The speed and slope of the waves obtained from the wave probe array agreed well with those obtained from the photographs taken using a high-speed camera. In the case of a steep wave, wave runup occurred at the bow before the wave reached the bow of the FPSO, so no impact load was generated, and only hydrostatic pressure was measured. Impact loads were generated in the spilling and plunging waves, and the magnitude of impact loads using the Von Karman's estimation formula and the impact loads measured in model tests showed similar values.

• 한국산업융합학회 논문집
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• 제24권6_2호
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• pp.841-848
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• 2021

This study investigated the acceleration characteristics of rock slopes when earthquakes, which have not been studied much in Korea, occur. The rock slope was modeled with a similar raw of 1/20 in consideration of the height(10m), roughness, strength, and the joint dips(20°). After the completion of the model, a shaking table tests was conducted according to the magnitude of the acceleration and the type of seismic wave. The maximum acceleration was greater in the short-period seismic wave than in the long-period seismic wave, and the maximum acceleration was larger in the small acceleration. The rock slope was close to a rigid block and a structure more vulnerable to the long period wave than to the short period wave. In the event of an earthquake smaller than the domestic earthquake-resistant maximum design acceleration(0.154g), safety management of the rock slope was required.

• 한국산업융합학회 논문집
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• 제23권2_2호
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• pp.245-254
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• 2020

This study investigated the so far little-researched characteristics of the behaviors of rock slopes at the time of an earthquake. For the selection of the rock block, a proper model was formed by applying the similarity in consideration of the roughness and strength of the rock slope(10m) on the site, and shaking table tests were carried out according to seismic excitement acceleration, and seismic waves. In the case of the inclination angle of the joint plane of 20°, the long period wave at 0.3g or more at the time of the seismic excitement surpassed the length of 100mm, the permissible displacement (0.01H, H:slope height), which brought about the collapse of the rock; the short period wave surpassed the permissible displacement at 0.1g, which caused the collapse of the slope. The rock slope was close to a rigid block and a structure more vulnerable to the long period wave than to the short period wave. It collapsed in the short period wave even at the seismic amplitude smaller than the maximum design acceleration in Korea.