• Physical Therapy Rehabilitation Science
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• v.9 no.1
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• pp.10-17
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• 2020

Objective: Hallux valgus (HV) is a common musculoskeletal deformity that is accompanied with pain and continues to decrease one's quality of life and ability to perform daily life activities by affecting gait and static stability. Therefore, this study aimed to investigate the effect of the angle of HV (HVA) and to compare the one-legged stance and gait parameters in young adults with less HV and severe HV. Design: Cross-sectional study. Methods: Forty young adults were divided into two groups, where HVA ≥15° (n=20) was defined as HV, and HVA <15° (n=20) was defined as normal. For balance ability, the center of pressure (COP) path, velocity, length of axis of the COP path, deviation of the x-axis and y-axis, and percentage of foot pressure were measured, and gait, the foot rotation angle, step length, percentage of each phase of the gait cycle, time change from the heel to forefoot, and maximum pressure of the forefoot and midfoot were measured. Results: Significant differences were found in sway length and time change from heel to forefoot during walking between the normal and HV groups (p<0.05). Most parameters were not associated with the HVA, but parameters such as length of axis and time to change from heel to forefoot were significantly associated with the HVA (p<0.05). Conclusions: These results suggest that most one-legged stance and gait parameters were not significantly affected by the HVA in young adults; therefore, future studies are needed in order to address other dynamic parameters and other methods of gait analysis for detecting clinically meaningful conditions.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.2
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• pp.285-293
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• 2017

Jump rope has two motions. It starts as hand motion and ends as jump motion. Therefore, two motions should be considered together to detect rotations accurately. But previous researches only consider one of the two motions as in push-up, sit-up, lift dumbbells etc, which results in inaccurate detection of rotations. In this paper, detection of rotation in jump rope using two motions through 6-axis accelerometer gyro sensor is proposed. Jump motion is detected using accelerometer sensor and hand motion is detected using gyro sensor. Also start point and end point of jump rope is detected using magnitude and standard deviation of accelerometer and gyro sensor values. The count of rotation is detected using y-axis of gyro sensor value. Y-axis of gyro sensor value indicate hand motion of jump rope motion. The usefulness of the proposed method is confirmed through experimental results.

• Korean Journal of Materials Research
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• v.4 no.7
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• pp.783-791
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• 1994

Piezoelectric ZnO thin films were deposited on 7059 glass substrate by rf magnetron sputtering. The effects of deposition parameter, such as rf power, gas pressure and $O_{2}$/Ar gas ratio, on the crystallinity and electrical properties of the deposited ZnO thin films were studied. It was found that the deposition rate was higher than the previously reported values. ZnO films were suitable for SAW filter since a standard deviation of XRD (002) peak rocking curve was less than $6^{\circ}$. ZnO thin films, which were deposited at $O_{2}$/Ar ratio larger than 25%, showed high resistance. SAW filter was fabricated using ZnO film, of which thickness was 0.25 of the wavelength of the propatating surface acoustic wave. The measured frequency response was consistent with the calculated one. The SAW filter had center frequency 39.08 MHz, phase velocity 2501 m/sec and insertion loss 29 dB.

• Journal of the Korean Geophysical Society
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• v.5 no.1
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• pp.29-39
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• 2002

Geophysical data sets from the Chojeong area in the Chungbok-Do are compositely studied in terms of multi-attribute interpretations for the subsurface mappings of shallow fracture zones, associated with groundwater reservoir. Utilizing a GIS software, the attribute data were implemented to a database; a lineament from the satellite image, electrical resistivities and its standard deviation, radioactivity, seismic velocity, and bedrock depth. In an attempt to interpret 1-D electrical sounding data in 3-D views, 1-D data are firstly performed horizontal and vertical inter- and extrapolation. Reconstruction of a resistivity volume is found to be an effective scheme for subsurface mapping of shallow fracture zones. Shallow fracture zones are located in the southeastern part of the study area, which are commonly correlated with the various exploration data.

• Journal of the Korean Applied Science and Technology
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• v.36 no.2
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• pp.448-455
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• 2019

This study aims to discover whether there are other factors, such as the ball position and address that will increase the percentage of holed putts from different angles of surface. In this study, we selected five male tour professional golfers that has been of 15 years or longer on the Korea Golf Association. As a research tool, after installing a video camera at an artificial site that's similar with the real green, and with the player's own putter, motion analysis was carried out using a Titleist V1x, which is commonly used by golfers. We use SPSS programs, significance level a=.05. According to the ball movement during the ball movement during the ball position putt by section, it is confirmed that the ball speed and angular velocity increase as the ball position changes from left to right. If the uphill putt, ball movement was found to be increased same change flat putt and There is no significance deviation. In this study, we investigate how the clubface and ball move during impact by varying the position of the address ball according to the slope during the ascent putt, which should increase the success rate among the various slopes. This study was conducted to present scientific data.

• Clinical and Experimental Pediatrics
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• v.62 no.7
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• pp.274-280
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• 2019

Purpose: To analyze the growth response to growth hormone (GH) therapy in prepubertal patients with Noonan syndrome (NS) harboring different genetic mutations. Methods: Twenty-three patients with prepubertal NS treated at Pusan National University Children's Hospital between March 2009 and July 2017 were enrolled. According to the disease-causing genes identified, the patients with NS were divided into 4 groups. Three groups were positive for mutations of the PTPN11, RAF1, and SOS1 genes. The five genes undetected (FGU) group was negative for PTPN11, RAF1, SOS1, KRAS, and BRAF gene mutations. The influence of genotype was retrospectively analyzed by comparing the growth parameters after GH therapy. Results: The mean chronological age at the start of GH treatment was $5.85{\pm}2.67years$. At the beginning of the GH treatment, the height standard deviation score (SDS), growth velocity (GV), and lower levels of insulin-like growth factor-1 (IGF)-1 levels were not statistically different among the groups. All the 23 NS patients had significantly increased height SDS and serum IGF-1 level during the 3 years of treatment. GV was highest during the first year of treatment. During the 3 years of GH therapy, the PTPN11, RAF1, and SOS1 groups showed less improvement in height SDS, IGF-1 SDS, and GV, and less increase in bone age-to-chronological age ratio than the FGU group. Conclusion: The 3-year GH therapy in the 23 prepubertal patients with NS was effective in improving height SDS, GV, and serum IGF-1 levels. The FGU group showed a better response to recombinant human GH therapy than the PTPN11, RAF1, and SOS1 groups.

• Journal of The Korean Society of Integrative Medicine
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• v.10 no.4
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• pp.1-9
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• 2022

Purpose : The purpose of this research is to propose a more efficient exercising method by measuring and comparing the movement of center of pressure (COP) while hemiplegic stroke patients perform kneeling squat exercise and squat exercise. Methods : 17 hemiplegic stroke patients were instructed to perform kneeling squat exercises and squat exercises, and the research was designed as a cross-over study. For data collection, a pressure distribution measurement platform (PDM) was used to measure the movement area, length, speed, and distance from the center of the X-axis of center of pressure. The data was then analyzed through a paired t-test. Results : Kneeling squat exercises have been found to have a significantly smaller center of pressure movement area compared to that of squat exercise(p<.001), and the center of pressure movement length of kneeing squat exercise has also been found to be relatively shorter (p<.001). Moreover, kneeling squat exercises have been found to have a significantly slower center of pressure movement speed than squat exercise (p<.001), and kneeing squat exercise center of pressure movement distance from the center of the X-axis has been found to be significantly small (p<.001). Conclusion : Kneeling squat exercises have significantly decreased amounts of center of pressure movement area, distance, and speed compared to squat exercises. Also, the center of pressure movement distance from the center of the X-axis was relatively closer. This result seems to derive from patients performing their motions with wide base surfaces while being refrained from using unstable ankle joints during kneeing squat exercise. Therefore, it can be concluded that kneeing squat exercises show relatively balanced center of pressure movements between the paralyzed and non-paralyzed sides because kneeling squats show smaller shakes in the center of pressure.

• Geomechanics and Engineering
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• v.34 no.6
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• pp.697-726
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• 2023

Brittleness as an important property of rock plays a crucial role both in the failure process of intact rock and rock mass response to excavation in engineering geological and geotechnical projects. Generally, rock brittleness indices are calculated from the mechanical properties of rocks such as uniaxial compressive strength, tensile strength and modulus of elasticity. These properties are generally determined from complicated, expensive and time-consuming tests in laboratory. For this reason, in the present research, an attempt has been made to predict the rock brittleness indices from simple, inexpensive, and quick laboratory test results namely dry unit weight, porosity, slake-durability index, P-wave velocity, Schmidt rebound hardness, and point load strength index using multiple linear regression, exponential regression, support vector machine (SVM) with various kernels, generating fuzzy inference system, and regression tree ensemble (RTE) with boosting framework. So, this could be considered as an innovation for the present research. For this purpose, the number of 39 rock samples including five igneous, twenty-six sedimentary, and eight metamorphic were collected from different regions of Iran. Mineralogical, physical and mechanical properties as well as five well known rock brittleness indices (i.e., B₁, B₂, B₃, B₄, and B₅) were measured for the selected rock samples before application of the above-mentioned machine learning techniques. The performance of the developed models was evaluated based on several statistical metrics such as mean square error, relative absolute error, root relative absolute error, determination coefficients, variance account for, mean absolute percentage error and standard deviation of the error. The comparison of the obtained results revealed that among the studied methods, SVM is the most suitable one for predicting B₁, B₂ and B₅, while RTE predicts B₃ and B₄ better than other methods.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.59 no.1
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• pp.44-54
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• 2023

In this study, the second-order Nomoto's nonlinear expansion model was implemented as a Tagaki-Sugeno fuzzy model based on the heading angular velocity to design the automatic steering system of a ship considering nonlinear elements. A Tagaki-Sugeno fuzzy PID controller was designed using the applied fuzzy membership functions from the Tagaki-Sugeno fuzzy model. The linear models and fuzzy membership functions of each operating point of a given nonlinear expansion model were simultaneously tuned using a genetic algorithm. It was confirmed that the implemented Tagaki-Sugeno fuzzy model could accurately describe the given nonlinear expansion model through the Zig-Zag experiment. The optimal parameters of the sub-PID controller for each operating point of the Tagaki-Sugeno fuzzy model were searched using a genetic algorithm. The evaluation function for searching the optimal parameters considered the route extension due to course deviation and the resistance component of the ship by steering. By adding a penalty function to the evaluation function, the performance of the automatic steering system of the ship could be evaluated to track the set course without overshooting when changing the course. It was confirmed that the sub-PID controller for each operating point followed the set course to minimize the evaluation function without overshoot when changing the course. The outputs of the tuned sub-PID controllers were combined in a weighted average method using the membership functions of the Tagaki-Sugeno fuzzy model. The proposed Tagaki-Sugeno fuzzy PID controller was applied to the second-order Nomoto's nonlinear expansion model. As a result of examining the transient response characteristics for the set course change, it was confirmed that the set course tracking was satisfactorily performed.

• Membrane Journal
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• v.33 no.1
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• pp.34-45
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• 2023

Two computational intelligence techniques namely artificial neural networks (ANN) and support vector machine (SVM) are employed to model the permeate flux based on seven input variables including time, transmembrane pressure, rotating velocity, the pore diameter of the membrane, dynamic viscosity, concentration and density of the feed fluid. The best-fit model was selected through the trial-error method and the two statistical parameters including the coefficient of determination (R²) and the average absolute relative deviation (AARD) between the experimental and predicted data. The obtained results reveal that the optimized ANN model can predict the permeate flux with R² = 0.999 and AARD% = 2.245 versus the SVM model with R² = 0.996 and AARD% = 4.09. Thus, the ANN model is found to predict the permeate flux with high accuracy in comparison to the SVM approach.