• Proceedings of the KSPS conference
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• 2000.07a
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• pp.364-364
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• 2000

It has been widely discussed in phonology that syllable structure of mother tongue influences one's acquisition of foreign language. However, the topic was hardly examined experimentally. So, we investigated effects of Korean syllable structure when Korean speakers pronounce English words, especially focusing on consonant strings that are not allowed in Korean. In the experiment, all the subjects are divided into 3 groups, that is, native, experienced, and inexperienced speakers. Native group consists of 1 male English native speaker. Experienced and inexperienced are each composed of 3 male Korean speakers. These 2 groups are divided by the length of residence in the country using English as a native language. 41 mono-syllable words are prepared considering the position (onset vs. coda), characteristic (stops, affricates, fricatives), and number of consonant. Then, the length of the consonant cluster is measured. To eliminate tempo effect, the measured length is normalized using the length of the word 'say' in the carrier sentence. Measurement of consonant cluster is the relative time period between the initiation of energy (onset I coda) which is acoustically representative of noise (consonant portion) and voicing. bar (vowel portion) in a syllable. Statistical method is used to estimate the differences among 3 groups. For each word, analysis of variance (ANDY A) and Post Hoc tests are carried out.

• The Journal of Korean Physical Therapy
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• v.27 no.4
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• pp.270-274
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• 2015

Purpose: The purpose of this study was to examine the electromyographic (EMG) activity of the abdominal muscles and to compare the activity ratios of the bilateral rectus abdominis (RA) to oblique abdominal muscles during shoulder abduction in opposite directions with single leg raising (SLR) performed in the supine position on a foam roller. Methods: Fifteen healthy subjects were recruited to the study. Each subject lay on the foam roller and performed left single leg raising with right or left shoulder $90^{\circ}$ abduction (Abd); performed in a random order. Surface EMG recordings of selected abdominal muscles (i.e., the RA, external oblique abdominis [EO], internal oblique abdominis [IO], and transverse abdominis [TrA]) were normalized to maximum voluntary isometric contraction. EO/RA and IO and TrA/RA ratios were determined with surface EMG. Data were analyzed by Independent t-test. The statistical significance level was p<0.05. Results: The results were as follows: (1) the right RA, left EO, and right IO and TrA muscle activities increased significantly at the left SLR with left Abd compared to the left SLR with right Abd (p<0.05); and (2) the ratio of right EO/RA activity increased significantly at the left SLR with right Abd compared to left Abd (p<0.05). Conclusion: These findings suggest that left SLR with left Abd on a foam roller is an appropriate exercise for activation of specific oblique abdominal muscles.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.6 no.2
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• pp.71-77
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• 2003

Forest fires happened simultaneously in Go-Seong, Gang-Neung, Sam-Cheok, Dong-Hae, Ul-Chin for 9 days(7th-15th of April, 2000). The area of those fires came to 23,794ha, about 80 times of Yeoui-Do and the extent of damage was the biggest and worst in Korea. The focus of this study is to compare the rate of restoration by damage types and develop the sound restoration model and efficient woodland management after the forest fire. The study site faces East Sea and the elements such as seasons, topographical features and etc. make difficult to obtain the suitable data from satellite. This study analyzed two images;2000yr and 2001yr after the fire. MODVI was more useful to grasp the damage than NDVI and the limitation of this study was the lack of images by damage types. The study suggests that lots of images are needed to monitor and analyze the forest fire site and the image of higher resolution is required to analyze the narrow site.

• Transactions of Materials Processing
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• v.29 no.4
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• pp.218-228
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• 2020

The prediction of final mass and optimized process conditions of injection molded products using Artificial Neural Network (ANN) were demonstrated. The ANN was modeled with 10 input parameters and one output parameter (mass). The input parameters, i.e.; melt temperature, mold temperature, injection speed, packing pressure, packing time, cooling time, back pressure, plastification speed, V/P switchover, and suck back were selected. To generate training data for the ANN model, 77 experiments based on the combination of orthogonal sampling and random sampling were performed. The collected training data were normalized to eliminate scale differences between factors to improve the prediction performance of the ANN model. Grid search and random search method were used to find the optimized hyper-parameter of the ANN model. After the training of ANN model, optimized process conditions that satisfied the target mass of 41.14 g were predicted. The predicted process conditions were verified through actual injection molding experiments. Through the verification, it was found that the average deviation in the optimized conditions was 0.15±0.07 g. This value confirms that our proposed procedure can successfully predict the optimized process conditions for the target mass of injection molded products.

• Journal of the Korean Society of Industry Convergence
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• v.2 no.2
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• pp.115-124
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• 1999

The interaction of weak normal shock wave with turbulent boundary layer in a supersonic nozzle was investigated experimentally by wall static pressure measurements and by schlieren optical observations. The lime-mean flow in the interaction region was classified into four patterns according to the ratio of the pressure $p_k$ at the first kink point in the pressure distribution of the interaction region to the pressure $p_1$ just upstream of the shock. It is shown for any flow pattern that the wall static pressure rise near the shock foot can be described by the "free interaction" which is defined by Chapman et al. The ratio of the triple point height $h_t$ of the bifurcated shock to the undisturbed boundary layer thickness ${\delta}_1$ upstream of the interaction increases with the upstream Mach number $M_1$, and for a fixed $M_1$, the normalized triple point height $h_t/{\delta}_1$ decreases with increasing ${\delta}_1/h$, where h is the duct half-height.

• Journal of the Korean Society for Precision Engineering
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• v.26 no.10
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• pp.56-64
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• 2009

This paper presents a parallel typed walking robot which can walk in omni-direction and climb from a floor to a wall. We design a six D.O.F leg mechanism composed of three legs, which form a parallel mechanism with a base and a ground to generate arbitrary poses. Optimal design is conducted to maximize the walking space and the dexterity, which are normalized by the stroke of leg. Kinematic parameters are found to maximize the weighted optimal objectives. We design a triple parallel mechanism robot by inserting Stewart platform between the upper leg mechanism and the lower leg mechanism and examine the gaits when the robot walks on the ground and climbs from a floor to a wall. The analysis of walking space and dexterity for each gait shows that the triple parallel walking robot has a large walking space with a large stability region. We explore the possibility that the robot can climb from a floor to a wall. Investigating the gaits for the six steps proves that the robot can lift the foot up to the wall by combining the orientational walking space generated by three parallel mechanisms.

• Korean Journal of Remote Sensing
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• v.34 no.1
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• pp.127-139
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• 2018

The GOCI atmospheric correction overland surfaces is essential for the time-series analysis of terrestrial environments with the very high temporal resolution. We develop an operational GOCI atmospheric correction method over land surfaces, which is rather different from the one developed for ocean surface. The GOCI atmospheric correction method basically reduces gases absorption and Rayleigh and aerosol scatterings and to derive surface reflectance from at-sensor radiance. We use the 6S radiative transfer model that requires several input parameters to calculate surface reflectance. In the sensitivity analysis, aerosol optical thickness was the most influential element among other input parameters including atmospheric model, terrain elevation, and aerosol type. To account for the highly variable nature of aerosol within the GOCI target area in northeast Asia, we generate the spatio-temporal aerosol maps using AERONET data for the aerosol correction. For a fast processing, the GOCI atmospheric correction method uses the pre-calculated look up table that directly converts at-sensor radiance to surface reflectance. The atmospheric correction method was validated by comparing with in-situ spectral measurements and MODIS reflectance products. The GOCI surface reflectance showed very similar magnitude and temporal patterns with the in-situ measurements and the MODIS reflectance. The GOCI surface reflectance was slightly higher than the in-situ measurement and MODIS reflectance by 0.01 to 0.06, which might be due to the different viewing angles. Anisotropic effect in the GOCI hourly reflectance needs to be further normalized during the following cloud-free compositing.

• Journal of the Korean Institute of Intelligent Systems
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• v.15 no.3
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• pp.357-362
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• 2005

Iris recognition system is the one of the most reliable biometries recognition system. An algorithm is proposed to determine the localized iris from the iris image received from iris input camera in client. For the first step, the algorithm determines the center of pupil. For the second step, the algorithm determines the outer boundary of the iris and the pupillary boundary. The localized iris area is transformed into polar coordinates. After performing three times Wavelet transformation, normalization was done using a sigmoid function. The converting binary process performs normalized value of pixel from 0 to 255 to be binary value, and then the converting binary process is compared pairs of two adjacent pixels. The binary code of the iris is transmitted to the server by the network. In the server, the comparing process compares the binary value of presented iris to the reference value in the database. The process of recognition or rejection is dependent on the value of Hamming Distance. After matching the binary value of presented iris with the database stored in the server, the result is transmitted to the client.

• Physical Therapy Korea
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• v.16 no.2
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• pp.9-15
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• 2009

The purposes of this study were to compare abductor hallucis (AbdH) muscle activity during toe curl exercise according to position of interphalangeal joint (IPJ). Fifteen healthy subjects with neutral foot were recruit for this study. All subjects performed toe curl exercise with towel while maintaining the IPJ in flexion (condition 1) and extension (condition 2). Toe curl exercise with towel was perform three trials for five second periods in each condition. Surface electromyography (EMG) activities were recorded from three muscles (AbdH, tibialis anterior, peroneous longus) in each condition. EMG activity was normalized to the value of maximal voluntary isometric contraction (%MVIC). The EMG activities acoording to position of IPJ were compared using a paired t-test. This study showed that the EMG activity of AbdH during toe curl exercise with IPJ extension significantly increased compared to those during toe curl exercise with IPJ flexion (p<.05). However, the EMG activity of tibialis anterior and peroneus longus were not significantly different between the conditions (p>.05). These results suggest that toe curl exercise with towel must be performed with extension of IPJ in order to strengthen intrinsic muscle in subjects with overuse injuries related to excessive pronation.

• Carbon letters
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• v.4 no.4
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• pp.185-191
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• 2003

Two types of carbon fiber based high modulus- and isotropic-pitch were exposed to isothermal oxidation in air and $CO_2$ gas and the weight change was measured by TGA apparatus. The kinetic equation was introduced $f=1-{\exp}(-at^b)$ and the constant b was obtained in the range of 1.02~1.68 for the isotropic fiber and obtained 0.91~1.93 for the high modulus fiber respectively. In considering the effect of the atmosphere for isothermal oxidation, the value of the constant b obtained in the carbon dioxide was higher than that obtained in the air. Therefore, it was found that the pitch based carbon fiber shows sigmoidal characteristic when it is oxidized in the carbon dioxide. In addition, it was also found that $k_f = 0.5$, which was reaction constant at f = 0.5, was a very useful parameter for evaluation of the oxidation reactivity of pitch based carbon fibers. According to the consideration, it is suggested that the conversion-time curves of the pitch based carbon fibers are correlated by normalized equation $f=1-{\exp}(-A{\tau}^B)$, where ${\tau}=t/t_f= 0.5$.