• Journal of Korean Society of Coastal and Ocean Engineers
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• v.34 no.6
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• pp.275-289
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• 2022

New businesses such as marine leisure and floating construction have recently flourished on the coast. As a result, consideration is given to a floating structure appropriate for marine environments. In this study, we applied a damping plate to increase the stability of a hybrid floating structure that was expanded by vertical and horizontal stacking of mobile unit modules. In the numerical analysis using ANSYS AQWA, the behavioral characteristics of the floating structure were analyzed according to the length change of the damping plate. However, the wave forces acting on a floating structure are excessively calculated by the resonance of fluid surrounded by the structure in the numerical analysis using potential flow. Therefore, we used the damping zone option of the ANSYS AQWA in the frequency domain analysis.

• Journal of Korean Physical Therapy Science
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• v.29 no.4
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• pp.43-53
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• 2022

Background: It is suggested that the decline in functional level due to aging influences the increase in traffic accidents among elderly drivers. Among the functions related to the driving behavior of older drivers, physical function is related to muscle strength and motor control, and aging causes deterioration of motor control and a defect in motor output variability. Method: Data Search The online databases used for literature search are PubMed, ProQuest(PML), NDSL, and literature searches were conducted from April 19 to April 26, 2022. For the search, 'aging', 'driving', and 'braking' were used in the investigation. Results: The physical functions related to the braking ability of elderly drivers were analyzed in muscle strength, reaction ability, motor control, and other related factors. In terms of muscle strength, 3 studies analyzed the above factors. 8 studies analyzed the above factors for response ability. For motor control, two studies analyzed the above factors. In addition, related factors were analyzed in one piece. Conclusion: As a result of the analysis, physical function for reaction ability showed the highest frequency, followed by the strength item with the highest frequency. This study suggests that factors that can increase physical function must be included in the development of a rehabilitation program for the driving ability of the elderly.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.2A
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• pp.215-222
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• 2008

This paper introduces an experimental verification of a tension estimation method based on system identification approach for a double hanger system on a suspension bridge. A laboratory model of such double hanger system has been made for this study. Total nine cases of the vibration tests have been conducted with respect to three levels of applied tension and three cases of the location of clamp. For a set of the collected acceleration response data, modal analysis has been followed in order to extract the natural frequencies and mode shapes of the selected cable systems. For the extracted modal parameters, the existing tension estimation methods based on the string theory and axially loaded beam theory have been firstly applied to estimate the tensile force on the double hanger cable system. Next, the tensile force on cables has been estimated by the system identification approach. It is seen that the errors in the tension estimation using the frequency-based system identification technique are about 3% for all cases while the estimation error using the existing method is up to 53.1%.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.3B
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• pp.269-279
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• 2009

The design flood estimation in a large river basin has a lot of uncertainties in areal reduction factors, time-spatial rainfall distribution, and parameters of rainfall-runoff model. The use of historical concurrent rainfall events for estimating design flood would reduce the uncertainties. This study presents a procedure for estimating design floods using historical rainfall events and storage function model. The design rainfall and time-spatial distribution were determined through analyzing concurrent rainfall events, and the design floods were estimated using storage function model with a non-linear hydrology response. To evaluate the applicability of the procedure of this study, the estimated floods were compared to results of frequency analysis of flood data. Both floods gave very similar results. It shows the applicability of the procedure presented in this study for estimating design floods in practices.

• Korean Journal of Health Psychology
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• v.15 no.3
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• pp.483-498
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• 2010

This study is to examine the effects of emotion regulation strategies in facial expressions and emotional experiences, based on the facial expressions of groups, using antecedent- and response- focused regulation. 50 female undergraduate students were instructed to use different emotion regulation strategies during the viewing of a disgust inducing film. While watching, their facial expressions and emotional experiences were measured. As a result, participants showed the highest frequency of action units related to disgust in the EG(expression group), and they reported in the following order of DG(expressive dissonance group), CG(cognitive reappraisal group), and SG(expressive suppression group). Also, the upper region of the face reflected real emotions. In this region, the frequency of action units related to disgust were lower in the CG than in the EG or DG. The results of the PANAS indicated the largest decrease of positive emotions reported in the DG, but an increase of positive emotions reported in the CG. This study suggests that cognitive reappraisal to an event is a more functional emotion regulation strategy compared to other strategies related to facial expression and emotional experience that affect emotion regulation strategies.

• Journal of Environmental Science International
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• v.33 no.1
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• pp.9-16
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• 2024

This study analyzed a survey of residents' awareness of rivers and water spaces that reflected residents' awareness in order to establish a basic park green space plan. Through this, the perception and requirements of rivers and water spaces were analyzed and important information was provided for urban planning and environmental management. As a result of analyzing residents' neutral satisfaction with rivers and their opinions on the frequency of use, role, and purpose, it was confirmed that rivers are recognized as an important part of urban life and contain the potential for development for a better urban environment. . However, considering the dissatisfied response and the relatively low frequency of use, we came to the conclusion that better urban planning and management is needed to meet the needs of residents by improving the river environment and providing various facilities. Based on this, city managers should focus on river management and improvement by actively collecting residents' opinions. Through analysis of the causes of dissatisfied responses, measures such as improving the environment around rivers and waste management should be prepared, and a broad strategy for environmental conservation and utilization should be established by reflecting the diverse expectations and demands of residents. These ongoing efforts are expected to have a positive impact on the sustainability of the city and improvement of residents' quality of life. Additionally, the results of this study will be able to contribute to establishing policies for urban planning and environmental improvement through similar research and analysis in other regions.

• Structural Engineering and Mechanics
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• v.90 no.6
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• pp.577-590
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• 2024

Considering the Column-Supported Group Silos (CSGSs) often arranged by rows in practical applications, earthquake responses will be affected by group effect. Since group effect presenting uncertainties, establishing the analytic model and evaluating characteristics of CSGSs seems necessary. This study aimed at providing a simplified method to evaluate seismic performances of the CSGSs. Firstly, the CSGSs with different storage granule heights are used as numerical examples to derive the base shear formula for three-particle dynamic analytical model. Then, the base shear distribution coefficient is defined as the group effect index. The simplified calculation method of the group silos based on the distribution coefficients is proposed. Finally, based on the empty, half, and full granular storage conditions, the empirical design parameters for the group silos system are given by combining finite element simulation with shaking table test. The group effect of storage granule heights of group silos on its frequency and base shear are studied by comparative analysis between group silos and independent single silo. The results show that the frequency of CSGSs decreases with the increasing weight of the stored granule. The connection between the column top and silo bottom plate is vulnerable, and structural measures should be strengthened to improve its damage resistance. In case of different storage granule heights, distribution coefficients are effective to reconstruction the group effect. The complex calculations of seismic response for CSGSs can be avoided by adopting the empirical distribution coefficients obtained in this study. The proposed method provides a theoretical reference for evaluation on the seismic performances of the CSGSs.

• Journal of Environmental Science International
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• v.33 no.8
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• pp.575-581
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• 2024

Insect pests are a significant threat to stored crops and can lead to considerable economic losses and reduced crop quality. Traditional pest control methods often involve chemical treatments, which have adverse environmental and health effects. This study evaluated the effectiveness of controlling the environment using LED lighting and plant-derived odor barriers as a dual strategy for insect pest control. The storage environment was altered using LED lights that emitted specific wavelengths (580-585 nm) and by reducing other wavelengths (300-500 nm). This light environment was combined with an insect odor barrier derived from Cinnamomum verum, Illicium verum, and Artemisia annua, and their duel impact on the behavior and frequency of insect pests under real storage conditions was determined. The findings revealed significant changes in the frequencies of various insect orders, indicating differential responses to light wavelengths and odor barriers. Notably, the introduction of an anti-insect light and odor barrier environment reduced Diptera and Hemiptera frequencies, which could potentially reduce pest intrusion. The results underscore the potential use of integrated light and odor barriers as a noninvasive and environmentally friendly approach to pest management. This study identifies the specific wavelengths and odor combinations that effectively deter insect pests and contribute to the development of more efficient and sustainable pest control methods. It also highlights the importance of understanding insect behavior and frequency changes in response to novel deterrent strategies.

• Journal of the Society of Naval Architects of Korea
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• v.61 no.5
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• pp.297-311
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• 2024

In this study, a combined seakeeping performance evaluation method has been developed for the design purpose of the light aircraft carrier CVX of Korean Navy. A frequency domain analysis method was developed for evaluation of safe operating envelope up to sea state 6, while a time domain analysis method was developed for survival condition of sea state 7 and higher. The frequency-domain solver AdFLOW-Navy was developed by adding empirical formula of roll damping and fin-stabilizer to the existing AdFLOW by KRISO, which was based on the three-dimensional higher order boundary element method (HOBEM). For the estimation of the roll damping coefficient, a two-dimensional cross-section was automatically extracted from the three-dimensional panel, and the roll damping coefficient was analyzed for the two-dimensional cross-section. As for the time domain analysis method, KIMAPS-Navy was developed by improving and expanding the KIMAPS series developed by KRISO which is based on the impulse response function by utilizing the hydrodynamic coefficients obtained from the AdFLOW-Navy. In addition, a weakly nonlinear analysis approach was applied to analyze highly nonlinear motion under heavy sea states. Finally numeraical analysis results were compared with model tests, which showed practical usefulness of the present combined seakeeping analysis approach.

• Radiation Oncology Journal
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• v.9 no.1
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• pp.53-58
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• 1991

From February 1987 through July 1990, the seventeen cases of inoperable intracranial arteriovenous malformation (AVM) were treated using 6 MV linear accelerator at the Division of Therapautic Radiology, Kang Nam 51. Mary's Hospital. Of seventeen cases, fourteen were male and three were female. Ages ranged from 10 to 51 years (median age of 25 years). The main symtoms were headache, epilepsy and hemiparesis in decreasing order of frequency. The middle cerebral artery is the most common origin of the feeding vessel $(41.2\%)$. Four were treated by conventionally fractionated radiation therapy (CRT, thirteen were treated by stereotactic radiosurgery (RS). duration or follow-up in CRT and RS group were 4 to 43 months (median 33 months) and 3 to 12 months (median 13 months), respectively. When the response was assessed by radiologic follow-up study, two of four CRT group showed minimal response. Of thirteen cases of RS group, two $(15.4\%)$ showed complete response, five $(38\%)$ partial response, two $(15.4\%)$ minimal response and four $(30.7\%)$ no response by the same assessment. There was no statistical significance in terms of follow-up period (p=0.22), size of lesion (p=0.82) and treated dose (p=0.05). Further accumulation of experience is recommended with proper case selection and sufficient follow-up period.