• Journal of the Institute of Convergence Signal Processing
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• v.19 no.4
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• pp.147-152
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• 2018

Underwater transient signals are complex, variable and nonlinear, resulting in a difficulty in accurate modeling with reference patterns. We analyze one type of underwater transient signals, in the form of whale sounds, using the MFCC(Mel-Frequency Cepstral Constant) and synthesize them from the MFCC and the weighted $L_2$-norm minimization techniques. The whales in this experiments are Humpback whales, Right whales, Blue whales, Gray whales, Minke whales. The 20th MFCC coefficients are extracted from the original signals using the MATLAB programming and reconstructed using the weighted $L_2$-norm minimization with the inverse MFCC. Finally, we could find the optimum weighted factor, 3~4 for reconstruction of whale sounds.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2009.10a
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• pp.781-786
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• 2009

The thesis shows that we gauged vibration of vehicular load regarding WPC girder bridge and researched into dynamic characteristics(natural frequency, vibration acceleration) of WPC girder bridge. By the basic of that, we researched on vibration serviceability by looking over and being compared to vibration criteria we had before. In the thesis, the gauged vibration made an analysis of vertical acceleration through FFT method and evaluated vibration serviceability about vibration sense the body feels by means of the standard of ISO assessment standard and Meister assessment standard by referring to analysis data. This research on bridge is WPC girder bridge of 90m span, width of 5.5m, and the experiment was gauged by a fluent which is right way and inverse way about dump truck of gross 270kN. Acceleration was located in the middle of 1st span, 2nd span, 3rd span. As a result of appraisal standard of Meister, the vibrations of the bridge have distributed between "Level C, Strongly Perceptible" and "Level B, Disturbing". Also the vibration can be attacked with unpleasant feeling. As a result of appraisal standard of ISO, from vibration influence didn't come to 60s, and reduced comfort boundary in part of most rigorous standard that such a case didn't happen.

• Journal of the Korean Institute of Intelligent Systems
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• v.24 no.4
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• pp.450-456
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• 2014

Humanoid robot is the most suitable robot platform for effective human and robot interaction. However, the robot's complicated body structure containing more than twenty joint actuators makes it difficult to generate stable and elaborate postures using the conventional inverse kinematic method. This paper proposes an alternative approach to generate difficult postures of touching an object placed in front of the foot by the left or right hand with its torso bent forward in single support phase using the fast computational optimization method, particle swarm optimization. The simulated postures are also applied to a commercial humanoid robot platform, which validates the feasibility of the proposed approach.

• Journal of applied mathematics & informatics
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• v.26 no.1_2
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• pp.213-222
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• 2008

Iterative methods are often suitable for solving least squares problems min$||Ax-b||_2$, where A $\epsilon\;\mathbb{R}^{m{\times}n}$ is large and sparse. The well known LSQR algorithm is among the iterative methods for solving these problems. A good preconditioner is often needed to speedup the LSQR convergence. In this paper we present the numerical experiments of applying a well known preconditioner for the LSQR algorithm. The preconditioner is based on the $A^T$ A-orthogonalization process which furnishes an incomplete upper-lower factorization of the inverse of the normal matrix $A^T$ A. The main advantage of this preconditioner is that we apply only one of the factors as a right preconditioner for the LSQR algorithm applied to the least squares problem min$||Ax-b||_2$. The preconditioner needs only the sparse matrix-vector product operations and significantly reduces the solution time compared to the unpreconditioned iteration. Finally, some numerical experiments on test matrices from Harwell-Boeing collection are presented to show the robustness and efficiency of this preconditioner.

• Korean Journal of Applied Biomechanics
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• v.22 no.3
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• pp.295-304
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• 2012

This study, through biomechanical analysis, conducts a risk assessment of injury occurrence in ballet dancers while they perform running and jumping movements. The participants were nine female collegiate students majoring in ballet(age: $20.89{\pm}1.17years$; height: $160.89{\pm}7.01cm$; mass: $48.89{\pm}3.26$). Descriptive data were expressed as $mean{\pm}standard$ deviation(SD) for all variables. An independent t-test was conducted to determine how the following variables differed: duration time, position of the center of gravity, angle of the hip, torque of the hip, and muscle activity. All comparisons were made at the p<0.05 significance level. The results show that the jump time was two times longer than the run time in the duration time. The jump length was also longer than the run. The angle of the hip and the torque at the hip were higher in the right. The vastus medialis muscle was most frequently used. These findings demonstrate that participants' jumps may require more biomechanical variables for performance of better and more correct $jet{\acute{e}}$.

• Journal of Acupuncture Research
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• v.35 no.3
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• pp.104-107
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• 2018

Background: Reduced impedance at acupuncture points (acupoints) is a well-known phenomenon; and the impedance has been found to reduce further in relation to organ stress. The author hypothesises that any changes to an organ's state or function are communicated to its related acupoints in real time. As part of a research project to demonstrate this communication, the impedance of several acupoints was studied in real time. Methods: The acupoints were located electrically, and a 40 kHz signal was used to sample the impedances. Samples were taken at each acupoint and also at a 6 mm radius. The sample rate was 1 kHz and the session lasted for 5 minutes. The results presented here were taken from a single patient. Results: The impedance at an acupoint's centre frequently changed in an inverse relationship to the impedance at a 6 mm radius (i.e. when one goes up, the other goes down) and the left and right instance of the same acupoint usually displayed different impedance features. Conclusion: When studying the fine detail of real-time impedance samples taken from the centre of an acupoint and also from a 6 mm radius, this previously unreported contrary-motion phenomenon provides a useful tool to differentiate between artefact and genuine organ-related features in an impedance trace.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.13 no.5
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• pp.191-199
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• 1993

Investigation is given to the detailed procedure of a computer assisted automatic technique for ortho-image generation from digital stereo image data of close-range photographs scanned by the CCD camera scanner. After rectification of geometric scanning errors, the bundle adjustment technique was used to determine the exterior orientation parameters of terrestrial camera. An automatic correlation matching technique was applied to search for the conjugate pixels in digital stereo pairs. And the 3-dimensional coordinates of the corresponding pixels were calculated by the space intersection method. For the generation of ortho-image from the calculated coordinates and right image data values, inverse-weighted-distance average method was used. And the accuracy of the resulting ortho-image was checked by comparing its image coordinates with there corresponding ground coordinates for the check points.

• Fashion & Textile Research Journal
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• v.4 no.6
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• pp.534-543
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• 2002

The purpose of this study was to identify the body proportions of girls in middle and high school who have been a major sales target of clothing manufacturers and thus to provide the basic information on the proportion of human body, which is essential for manufacturer to produce clothing and for individual consumers to select right apparels to wear and purchase. The subjects were 133 girls in middle school and 141 girls in high school. As measuring instruments, the Martin's anthropometer, tapelines, and belts for marking waistline were used. In order to analyze the data, t-test and factor analysis were used. The measurement of vertical distance between vertex and measuring points, showed a significant difference between the high school group and middle school group in every item. In the comparison of eight head proportion between the two groups, middle school students had 7.2 head proportion while girls in high school had 6.9 head proportion in detail. The factor analysis of major divided body parts of the two groups indicated that waist-hip and hip-crotch, constituting lower trunk together, vertex-apex nasi, and apex nasi-back neck point, constituting head together, back neck point-spina scapula and spina scapula-waist, constituting posterior of upper body together, and mentum-bust point and bust point-waist, constituting anterior of upper body together, were in inverse proportion.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.1
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• pp.107-112
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• 2018

One-dimensional numerical model is implemented to investigate temperature variations in the mixed layer depth (MLD) with the passage of typhoons. In the model, we assume a non-divergent, infinite ocean and consider wind effects only, excluding isostatic effects (inverse barometric effects) and upwelling with vertical movement of the water column. Numerical experiments investigate the effects of typhoon tracks on temperature variations, including their dependence on vertical resolutions in the MLD and these results are compared with those in a three-dimensional primitive equation model (POM). The model reproduces features of the observed temperature variations in the MLD fairly well, and implies that wind effects, rather than isostatic effects, play a predominant role in temporal and spatial temperature variations in the MLD. After the passage of typhoons, however, the model does not reproduce well the temperature variations observed in the MLD, because a limitation of the model is its inability to reproduce events such as cyclonic eddy formation (Hong et al., 2011; Masuda and Hong, 2011). The model also shows well the so called 'rightward bias' (Price, 1981) of sea surface cooling which is the most predominant in the right hand side of typhoon's track.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.20 no.4
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• pp.331-337
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• 2010

The thesis shows that we gauged vibration of vehicular load regarding WPC girder bridge and researched into dynamic characteristics(natural frequency, vibration acceleration) of WPC girder bridge. By the basic of that, we researched on vibration serviceability by looking over and being compared to vibration criteria we had before. In the thesis, the gauged vibration made an analysis of vertical acceleration through FFT method and evaluated vibration serviceability about vibration sense the body feels by means of the standard of ISO assessment standard and Meister assessment standard by referring to analysis data. This research on bridge is WPC girder bridge of 90 m span, width of 5.5 m, and the experiment was gauged by a fluent which is right way and inverse way about dump truck of gross 270 kN. Acceleration was located in the middle of 1st span, 2nd span, 3rd span. As a result of appraisal standard of Meister, the vibrations of the bridge have distributed between "level C, strongly perceptible" and "level B, disturbing". Also the vibration can be attacked with unpleasant feeling. As a result of appraisal standard of ISO, from vibration influence didn't come to 60s, and reduced comfort boundary in part of most rigorous standard that such a case didn't happen.