• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.22 no.8
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• pp.96-103
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• 2008

In this paper, a new algorithm based on sensitivity method for alleviating overloads in power networks is presented to find the switching branches effectively. By applying the new sensitivity of the line flow with respect to the change of the branch impedance, both on and off switchings for alleviating overloads in power networks are performed systematically at once and an effective scheme for drawing up a plan to alleviate overloads of the lines is presented through screening a large number of line switching cases easily. The ranking of switching branches is calculated according to the new switching algorithm based on sensitivity method and the switching of the ranked branches is performed in the order of ranking until overloads are eliminated. In order to show the effects of this algorithm, it is applied to a small scale power system of IEEE 39-bus test system.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.1
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• pp.419-424
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• 2006

In recent years, the repairing work of the small boats in dock have pointed out a defects of the many FRP shipbuiling because of a term of works and working-space and man-power. In the paper, By carried out the model tests and structure analysis of the floating dock were mainly drawing on the concept design of the floating dock systems that the above defects were solved.

• Journal of the Korean Society of Physical Medicine
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• v.7 no.3
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• pp.319-327
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• 2012

Purpose : This study aimed to identify the asymmetry observed in the rehabilitative ultrasound imaging of lateral abdominal muscle thickness and performance between the affected and unaffected side during the abdominal drawing-in maneuver (ADIM), an exercise used to facilitate activation of selectively TrA to stabilize the trunk prior to limb movement. Methods : The Participants were twenty one patients with post-stroke hemiplegia in this study. Ultrasound imaging was used to measure amount of changes in thickness of the external oblique (EO), internal oblique (IO), transversus abdominis (TrA). A Paired t-test was used to compare relaxed muscle thickness to contracted muscle thickness of all 3 muscles between the affected and unaffected sides. Results : The outcome measures included side to side differences of absolute thickness, contraction ratio among the lateral abdominal muscles. There was no significantly difference in between the affected and unaffected side at rest. But, there was a significantly difference in absolute muscle thickness between the affected and unaffected side of only TrA muscle. Also contraction ratio was a significantly difference between the affected and unaffected TrA muscle. Conclusion : These findings support the asymmetrical activation of TrA muscle during abdominal muscle contraction in patients with post-stroke hemiplegia. Further studies are warranted for confirming this outcome.

• Journal of the Korean Society for Heat Treatment
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• v.21 no.4
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• pp.183-188
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• 2008

Hot press forming allows geometrically complicated parts to be formed from sheet and the rapid cooling hardens them to extremely high strength. The main purpose of this research is to characterize Al coated layer in Al coated boron steel during hot press forming. For the hot press hardening experiment, test specimens were heated up to $810{\sim}930^{\circ}C$ and held for 3, 6 and 9 minutes, respectively. And then, some specimens were press hardened and others were air-cooled without any pressing for the comparison purpose. Al coated layer shows four distinct micro-structural regions of interest; diffusion zone, Al-Fe zone(I) low-Al zone(LAZ) and Al-Fe zone(II). Band-like LAZ is clearly shown at temperature ranges of $810{\sim}870^{\circ}C$ and sparsely dispersed at temperature higher than 900oC. The micro-cracking behavior in the Al coated layer during forming were also analyzed by bending and deep drawing tests. The strain concentration in softer LAZ is found to be closely related with micro-cracking and exfoliation in coated layer during forming.

• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.2
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• pp.62-69
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• 2016

This paper proposes to select Measure of Performance(MOP) for object attainment in the counterfire operation and deduce the reasonable combination of blue force's hitting resources satisfying MOP's optimal value and regression equation for the object achievement time. Also, in the study-methodological perspective, a series of procedures for drawing the regression equation from the real world is presented. Firstly the model was made by simplifying the weapon-system information of red force and blue force, then the time for object attainment was derived from its simulation. Simulating the model for the counterfire operation was divided into three phases-detection, decision and hitting. The probability method by applying the random numbers were used for detection, fixed constant numbers for decision and hitting. The simulation was repeatedly performed to get the minimum time for the object attainment against the fixed enemy, and it was estimated as the optimal value of simulation. From this result, the optimum combination of blue force's weapon system against the red force and finally, the regression equation were obtained by using the response surface analyzing method in MINITAB. Thereafter this equation was completely verified by using 'the 2-sample t-test.' As a result, the regression equation is suitable.

• Korea Real Estate Review
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• v.27 no.3
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• pp.71-86
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• 2017

The purpose of this study was to apply the deep running method to real estate price index predicting and to compare it with the time series analysis method to test the possibility of its application to real estate market forecasting. Various real estate price indices were predicted using the DNN (deep neural networks) and LSTM (long short term memory networks) models, both of which draw on the deep learning method, and the ARIMA (autoregressive integrated moving average) model, which is based on the time seies analysis method. The results of the study showed the following. First, the predictive power of the deep learning method is superior to that of the time series analysis method. Second, among the deep learning models, the predictability of the DNN model is slightly superior to that of the LSTM model. Third, the deep learning method and the ARIMA model are the least reliable tools for predicting the housing sales prices index among the real estate price indices. Drawing on the deep learning method, it is hoped that this study will help enhance the accuracy in predicting the real estate market dynamics.

• The Journal of Korean Society for School & Community Health Education
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• v.21 no.1
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• pp.33-45
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• 2020

Objectives: The purpose of this study is to analyze the research trends on oral health literacy in South Korea and to suggest the direction of future research, Methods: The literatures were searched using KISS, RISS, KMBASE, KoreaMed, Nanet and NDSL. A total of 17,433 documents were retrieved by database searching. The final 34 literatures that satisfied the inclusion criteria were selected for analyzing. A content analysis was performed on 34 literatures on the topics of oral health literacy which had been published from 2012 to 2019. Results: Most of the 34 literatures, 23 articles and 11 thesises were descriptive-correlation studies, but there was no intervention study. The participants studied in the selected literatures were mostly adults followed by elderly and other groups including foreigner. More troubling sufficient samples and sampling methods were lacking at the population level. The validation of the used health literacy instruments was not sufficient. Conclusions: The unification of translation terminology for oral health literacy and the standardized instrument to test oral health literacy are needed. And to improve the level of oral health literacy, studies should be conducted using various variables. It is also necessary to develop the oral health education programs that can improve the level of oral health literacy. In the future, meta-analysis on the oral health literacy are needed for cumulating findings and drawing more reliable and general conclusions.

• Journal of the Korea Society for Simulation
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• v.28 no.2
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• pp.169-177
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• 2019

LVC(Live-Virtual-Constructive) training system is drawing attention due to changes in battlefield situation and the development of advanced information and communication technologies. The ROKAF(Republic of Korea Air Force) plans to construct LVC training system capable of scientific training. This paper analyzes the results of V-C interoperability test with three fighter simulators as virtual systems and a theater-level wargame model as a constructive system. The F-15K, KF-16, and FA-50 fighter simulators, which have different interoperable methods, were converted into a standard for simulation interoperability. Using the integrated field environment simulator, the fighter simulators established a mutually interoperable environment. In addition, the Changgong model, which is the representative training model of the Air Force, was converted to the standard for simulation interoperability, and the integrated model was implemented with optimized interoperability performance. Throughput experiments, It was confirmed that the fighter simulators and the war game model of the ROKAF could be interoperable with each other. The results of this study are expected to be a good reference for the future study of the ROKAF LVC training system.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.27 no.2
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• pp.45-54
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• 2021

Background: The purpose of this study was to investigate the effects of flexi-bar exercise on shoulder pain, dysfunction, quality of life, and range of motion of women with breast cancer surgery. Methods: A total of 42 female patients who had breast cancer were included in this study. By drawing lots, subjects were divided into a flexi-bar exercise group (FBG, n=21) and a general breast cancer group (GBG, n=18). The effects of flexi-bar exercise on patients were evaluated in terms of the visual analogue scale (VAS), the shoulder pain and disability index (SPADI), the European organization for the research and treatment of cancer quality of life questionnaire (EORTC QLQ-C30), the breast cancer specific EORTC quality of life questionnaire (EORTC QLQ-BR23), and range of motion (ROM), all of which were measured pre- and post- intervention followed by evaluation. Results: A significant increase was pain, functional disability level, quality of life, ROM within the two groups (p<.01). There were pain, functional disability level, quality of life, ROM post test then invention were significant between the two groups(p<.01). Conclusion: The flexi-bar exercise has a positive treatment effect on breast cancer patients.

• Structural Engineering and Mechanics
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• v.77 no.2
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• pp.179-196
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• 2021

Experimental investigations on the seismic behaviors of the PVC-FRP Confined Reinforced Concrete (PFCRC) columns under low cyclic loading are carried out and two variable parameters including CFRP strips spacing and axial compression ratio are considered. The PFCRC column finally fails by bending and is characterized by the crushing of concrete and yielding of the longitudinal reinforcement, and the column with a high axial compression ratio is also accompanied by the cracking of the PVC tube and the fracture of CFRP strips. The hysteretic curves and skeleton curves of the columns are obtained from the experimental data. With the increase of axial compression ratio, the stiffness degradation rate accelerates and the ductility decreases. With the decrease of CFRP strips spacing, the unloading sections of the skeleton curves become steep and the ductility reduces significantly. On the basis of fiber model method, a numerical analysis approach for predicting the skeleton curves of the PFCRC columns is developed. Additionally, a simplified skeleton curve including the elastic stage, strengthening stage and unloading stage is suggested depending on the geometric drawing method. Moreover, the loading and unloading rules of the PFCRC columns are revealed by analyzing the features of the skeleton curves. The quantitative expressions that are used to predict the unloading stiffness of the specimens in each stage are proposed. Eventually, an analytical model for the PFCRC columns under low cyclic loading is established and it agrees well with test data.