• Transactions of the Korean Society of Mechanical Engineers A
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• v.38 no.10
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• pp.1139-1145
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• 2014

Creation of a human skeleton model and characterization of the variation in the bone shape are fundamentally important in many applications of biomechanics. In this paper, we present a parametric shape modeling method for femurs that is based on extracting the main parameter of variations of the femur shape from a 3D model database by using statistical shape analysis. For this shape analysis, principal component analysis (PCA) is used. Application of the PCA to 3D data requires bringing all the models in correspondence to each other. For this reason, anatomical landmarks are used for guiding the deformation of the template model to fit the 3D model data. After subsequent application of PCA to a set of femur models, we calculate the correlation between the dominant components of shape variability for a target population and the anatomical parameters of the femur shape. Finally, we provide tools for visualizing and creating the femur shape using the main parameter of femur shape variation.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.05
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• pp.406-409
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• 1997

In this paper, the power spectral analysis and fractral dimension analysis of heart rate variability(HRV) were performed to evaluate effects of orthostatic stress with head-up tilt on autonomic nervous system(ANS) for 24 young and healthy subjects(age: $24{\pm}5yr$.). The ECG and respiration signals were recorded at the tilt angle of $0^{\circ},\;15^{\circ},\;30^{\circ},\;45^{\circ},\;70^{\circ}$ and $90^{\circ}$ successively for 5 minutes per each stage under the condition of frequency controlled respiration (0.25Hz). Heart rate(HR) gradually increased as the angle increased. Similarly, according to the increment of angle, normalized low frequency(LF) component(0.05-0.15Hz) gradually increased, whereas normalized high frequency(HF) component (0.20-0.30Hz) was reduced. From these results it is speculated that orthostatic stress, head-up tilt, results in the prevalence of sympathetic tone in autonomic balance with the increment of sympathetic tone and the decrement of parasympathetic tone, which seems to mean that autonomic nervous system plays a major role in compensating for disturbances of cardiovascular system due to it.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.83-83
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• 2017

The National Agrobiodiversity Center (NAS, RDA, Republic of Korea) has continually collected new valuable genetic resources. In this study, we regenerated conserved kidney bean (Phaseolus vulgaris L.) germplasm which couldn't be available because of seed quantity and quality, and we also surveyed their morphological characters for the sustainable utilization. A total of 431 kidney bean accessions were regenerated and 18 morphological traits were surveyed according to the characterization guideline of RDA Genebank. Among the surveyed traits, flowering time ranged from May 23 to September 4 and 73.8% of tested accessions were mainly flowering in June. The maturity time ranged from July 1 to October 15 and main flowering time was July (91.4%). For plant type, 270 accs (62.6%) were climbing type followed by medium type of 86 accs (20.0%) and dwarf type of 65 accs (15.1%). The seed coat colors were various; yellow (34.6%), white (22.3%), brown (17.9%), red (10.7%), black (5.8%), violet (11%), pink (1.4%), navy (0.9%). Principal component analysis indicated that five principal components (PCs) with Eigen values >1 accounted for more than 65.8% variability. The first PC was more related to growth habits such as growth type, flowering time, and plant type. The second and third PCs showed higher values of the pigment characters such as seed coat color, flower color, and pod color. In fourth and fifty PCs, there were the higher positive values of the pod shapes. Our results provided insight into the characteristics kidney beans, thus the utilization basis of kidney beans might be elevated for bio-industry.

• Journal of the Korean Society of Physical Medicine
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• v.10 no.1
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• pp.9-14
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• 2015

PURPOSE: The purpose of this study was to investigate the effects of ten minutes of manual passive exercise performed by physical therapists on autonomic nervous system. METHODS: Thirty-five healthy adults, both male and female, were chosen as subjects for this study. The autonomic nervous system was measured by heart rate variability (HRV),before and after passive exercise using the following measurements: mean heart rate (mean HRT), low frequency (LF) and high frequency (HF) components, the LF/HF ratio, root mean square of the successive differences (RMSSD), and the HRV index. The exercise was performed on the subjects by a physical therapist with seven years of experience specializing in the nervous system. The exercise was conducted at the mid-range of motion on the upper and lower limbs of the subjects for two minutes and thirty seconds and for a total of ten minutes. RESULTS: There was a significant increase in the LF component. The mean HRT and the LF/HF ratio both increased, but these increases were not significant. The HF component, RMSSD, and HRV index all decreased, but these decreases were not significant. CONCLUSION: In conclusion, mid-range manual passive exercise does not induce stress on the autonomic nervous system. It can safely be performed by a physical therapist.

• Ocean and Polar Research
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• v.43 no.4
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• pp.219-227
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• 2021

Sea surface height (SSH) anomalies were estimated from data recorded by four pressure-recording inverted echo sounders (PIESs) in the Mindanao Current region over a duration of 2 years from December 2017 to November 2019. The steric components of SSH anomalies were derived from round-trip acoustic travel times from the sea floor to the sea surface, whereas mass-loading components were derived from bottom pressures. Temporal variabilities in the total (steric and mass-loading) SSH anomalies and the steric component are extremely similar; this result implies that the steric component plays a major role in SSH anomalies in this region. Comparisons of the PIES-derived SSH anomalies with satellite-measured SSH anomalies reveal that the former has less temporal variability. Correlation coefficients between the total SSH anomalies and satellite-measured SSH anomalies are less than 0.85, which is lower than the correlation coefficient between the steric components and satellite-measured SSH anomalies.

• The Korean Journal of Physiology and Pharmacology
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• v.27 no.1
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• pp.49-59
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• 2023

Metabolic syndrome (MetS) involves multi-factorial conditions linked to an elevated risk of type 2 diabetes mellitus and cardiovascular disease. Pre-metabolic syndrome (pre-MetS) possesses two MetS components but does not meet the MetS diagnostic criteria. Although cardiac autonomic derangements are evident in MetS, there is little information on their status in pre-MetS subjects. In this study, we sought to examine cardiac autonomic functions in pre-MetS and to determine which MetS component is more responsible for impaired cardiac autonomic functions. A total of 182 subjects were recruited and divided into healthy controls (n=89) and pre-MetS subjects (n=93) based on inclusion and exclusion criteria. We performed biochemical profiles on fasting blood samples to detect pre-MetS. Using standardized protocols, we evaluated anthropometric data, body composition, baroreflex sensitivity (BRS), heart rate variability (HRV), and autonomic function tests (AFTs). We further examined these parameters in pre-MetS subjects for each MetS component. Compared to healthy controls, we observed a significant cardiac autonomic dysfunction (CAD) through reduced BRS, lower overall HRV, and altered AFT parameters in pre-MetS subjects, accompanied by markedly varied anthropometric, clinical and biochemical parameters. Furthermore, all examined BRS, HRV, and AFT parameters exhibited an abnormal trend and significant correlation toward hyperglycemia. This study demonstrates CAD in pre-MetS subjects with reduced BRS, lower overall HRV, and altered AFT parameters. Hyperglycemia was considered an independent determinant of alterations in all the examined BRS, HRV, and AFT parameters. Thus, hyperglycemia may contribute to CAD in pre-MetS subjects before progressing to MetS.

• The Journal of Korean Physical Therapy
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• v.6 no.1
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• pp.133-145
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• 1994

The purpose of this study were 1) to describe the rolling movements of the twenties, 2) to identify developmental sequences of three body regions and 3) to evaluate the influence gender might have on the movement patterns used for rolling. Fifty males(mean 23.2 years of age) and fifty females(mean 21.1 years of age) performed the 10 trials of rolling from a supine to a prone position while being videotaped. Individual videotaped trials were classified using the described categories for upper extremity, lower extremity and head-trunk component. The most common combination of movement patterns described. The results of this study were as follows : 1. Only $16\%$ of males and $12\%$ of females demonstrated a same combination of movements during rolling. 2. Gender differences were found in the incidence of movement patterns of each body region. 3. This study determined if head-trunk anion might develop in advance of limb action. 4. This study determined if upper extremity action might develop in advance of lower extremity action. The variability of adults' rolling movement provides physical therapists with numeous movement combinations that might be used when teaching patterns to rolling.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.5
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• pp.561-568
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• 2003

Surface ozone concentrations are highly sensitive to meteorological variability. Therefore, in order to reveal the long-term changes in ozone due to the changes in precursor emissions, we need to remove the effects of meteorological fluctuations on the annual distribution of surface ozone. In this paper, the meteorologically adjusted trends of daily maximum surface ozone concentrations in two major Korean cities (Seoul and Busan) are investigated based on ozone data from 11 (Seoul) and 6 (Busan) sites over the period 1992 ∼ 2000. The original time series consisting of the logarithm of daily maximum ozone concentrations are splitted into long-term, seasonal and short-term component using Kolmogorov-Zurbenko (KZ) filter. Meteorological effects are removed from filtered ozone series using multiple linear regression based on meteorologcial variables. The long-term evolution of ozone forming capability due to changes in precursor emission can be obtained applying the KZ filter to the residuals of the regression. The results indicated that meteorologically adjusted long-term daily maximum ozone concentrations had a significant upward trend (Seoul: ＋ 3.02% yr$^{-1}$ , Busan: ＋ 3.45% yr$^{-1}$ ). These changes of meteorologically adjusted ozone concentrations represent the effects of changing background ozone concentrations as well as the more localized changes in emissions.

• Earthquakes and Structures
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• v.11 no.4
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• pp.701-721
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• 2016

Base isolation is a well-established passive strategy for seismic response control of buildings. In this paper, an efficient framework is proposed for reliability-based design optimization (RBDO) of isolated buildings subjected to uncertain earthquakes. The framework uses reduced function evaluations method, as an efficient tool for structural reliability analysis, and an efficient optimization algorithm for optimal structural design. The probability of failure is calculated considering excessive base displacement, superstructure inter-storey drifts, member stress ratios and absolute accelerations of floors of the isolated building as failure events. The behavior of rubber bearing isolators is modeled using nonlinear hysteretic model and the variability of future earthquakes is modeled by applying a probabilistic approach. The effects of pulse component of stochastic near-fault ground motions, fixity-factor of semi-rigid beam-to-column connections, values of isolator parameters, earthquake magnitude and epicentral distance on the performance and safety of semi-rigidly connected base-isolated steel framed buildings are studied. Suitable RBDO examples are solved to illustrate the results of investigations.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.2
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• pp.78.1-78.1
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• 2017

We present a noble method to determine BH mass of many AGNs directly through reverberation mapping using a small telescope with wide-field of view. In 2017 August we installed five medium-band filters to a 0.25m diameter $5deg^2$ FOV telescope at the McDonald observatory. The width of these filters (FWHM ~ 50nm) are matched to the broad line width of type-1 AGNs at various redshifts. From recently obtained data, about r ~ 19 magnitude AGNs can be detected in line component with 150s exposure. With this magnitude limit, about 20~30 AGNs can be studied in one field. We plan to carry out at one day cadence observation over 20~30 fields, enabling us to monitor up to ~1000 AGNs over a wide range of variability. This poster presents out plan and early results from test observation.