• The Journal of Korean Physical Therapy
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• v.28 no.2
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• pp.136-141
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• 2016

Purpose: In this study experiments were performed during 6 weeks with 40 adults, 20 subjects in the waist stabilization exercise with blood flow restriction group and 20 subjects in the waist stabilization exercise without blood flow restriction group, in order to determine the impact of waist stabilization exercise on White Area Index (WAI) followed by blood flow restriction. Methods: Thickness of external oblique abdominal muscle, internal oblique abdominal muscle, and transversus abdominis muscle, as well as density and WAI of external oblique abdominal muscle were measured, followed by performance of repeated ANOVA. Results: Significant difference in thickness of external oblique abdominal muscle according to periodical difference was observed between groups (p<0.05). Significant difference in thickness of internal oblique abdominal muscle and transversus abdominis muscle according to periodical difference was observed between groups (p<0.05). Significant difference in density and WAI of external oblique abdominal muscle according to periodical difference was observed between groups (p<0.05). Conclusion: In conclusion, significant difference was observed after waist stabilization exercise with blood flow restriction. These results can be used as basic data for future research on waist stabilization exercise and blood flow restriction exercise.

• Journal of Korean Physical Therapy Science
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• v.12 no.4
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• pp.57-67
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• 2005

The purpose of this study is to investigate the effect of low back pain(LBP) and pelvic displacement on foot orthosis. Before and after experiments were designed to compare the effect. 21 LBP patients who were the subjects diagnosed of applying foot orthosis for 3 weeks after, investigated about pelvic obliquity angle, displacement of ilium, lumbo-sacral angle by x-ray test which is one of pelvic displacement tests, visual analogue scale is used for LBP measurement. The result show the followings; First, Pelvic obliquity angle was significantly reduced after applying foot orthosis compared before using it(p<.05). Second, Displacement of ilium was significantly reduced after applying foot orthosis compared before using it(p<.05). Third, Lumbo-sacral angle was significantly reduced after applying foot orthosis compared before using it(p<.05). Fourth, LBP was significantly reduced after applying foot orthosis compared before using it(p<.05). This study tries to suggest new LBP treatment to reduce pelvic displacement by apply foot orthosis. In conclusion, foot orthosis reduces pelvic obliquity angle, displacement of ilium, lumbo-sacral angle and also decrease LBP. Further more, It needs of biomechanical study which can recognize relation between foot arch and pelvic displacement. This study will serve as a clinically useful data for diagnosis and treatment of LBP and biomechanical analysis of lower limb.

• Korean Journal of Cognitive Science
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• v.14 no.4
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• pp.53-63
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• 2003

We analyzed the relationships between facial impressions and physical features, and investigated the effects of impressions on facial similarity judgments. Using 79 faces extracted from a face database, we collected the ratings of impressions along four dimensions -mild-fierce, bright-dull, feminine-manly and youthful-mature- and the measures of 41 physical features. Multiple Regression Analyses showed that the ratings of impressions and the measures of features are closely connected with each other. Our experiments using facial similarity judgments confirmed the possibility that facial impressions are used in processing of facial information. We found that people tend to perceive faces as similar when they have the same impressions rather than neutral ones, although all of them are alike physically. These results imply that facial impressions are used as a psychological structure representing facial appearance, and that facial processing includes impression information.

• Journal of Korean Physical Therapy Science
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• v.19 no.4
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• pp.1-6
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• 2012

Purpose : The current research examines the muscle activity that happens during scaling practice subject to 20 dental hygienic students with musculoskeletal pain and then propose a basic data according to the working attitude of the Dental Hygienist. Method : The Nordic-style questionnaire is used to define experimental group with musculoskeletal pain and control group. During the scaling the surface EMG device is used to measure the muscle activity of experimental and control group. Study design : The surface EMG is measure RMS(root mean square) of suboccipital muscle, biceps brachii, upper trapezius, and brachioradialis muscle activity. Results : In the experimental group, the RMS of upper trapezius and brachioradialis is increased during scaling practice(p<0.05), but the control group's RMS is not changed(p>0.05). Conclusion : Musculoskeletal pain may contribute to increase muscle activity of neck & arm during scaling practice. In the future we think there is a need to raise the office efficiency by subjecting to dental hyginiest that are in the clinics and performing experiments.

• ETRI Journal
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• v.35 no.2
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• pp.245-252
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• 2013

In this work, we study the physical layer solutions for 10-gigabit-capable passive optical networks (PONs), particularly for an optical link terminal (OLT) including a 10-Gbit/s electroabsorption modulated laser (EML) and a 2.5-Gbit/s burst mode receiver (BM-Rx) in a novel bidirectional optical subassembly (BOSA). As unique features, a bidirectional mini-flat package and a 9-pin TO package are developed for a 10-gigabit-capable PON OLT BOSA composed of a 1,577-nm EML and a 1,270-nm avalanche photodiode BM-Rx, including a single-chip burst mode integrated circuit that is integrated with a transimpedance and limiting amplifier. In the developed prototype, the 10-Gbit/s transmitter and 2.5-Gbit/s receiver characteristics are evaluated and compared with the physical media dependent (PMD) specifications in ITU-T G.987.2 for XG-PON1. By conducting the 10-Gbit/s downstream and 2.5-Gbit/s upstream transmission experiments, we verify that the developed 10-gigabitcapable PON PMD prototype can operate for extended network coverage of up to a 40-km fiber reach.

• International Journal of Automotive Technology
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• v.7 no.1
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• pp.51-59
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• 2006

The high potential for injury involved in rollover accidents warrants the development of a system to protect passengers against such events. To effectively implement such a protection system, it is first necessary to determine rollover criteria (i.e., real time states which indicate the occurrence of rollover events). In this paper, several rollover criteria have been developed based on simplified physical models. Such accidents are first classified into two types, untripped and tripped, according to the main cause that initiates the rollover. Characteristics of these rollover situations are identified by applying appropriate principles of dynamics to corresponding simplified physical models. Two main rollover criteria, Rotational Kinetic Energy (RKE) and Initial Kinetic Energy (IKE), are then introduced based on these characteristics. ADAMS/View simulations have been performed to verify the feasibility of the introduced rollover criteria. ADAMS/Car simulations have also been conducted to get more realistic rollover data with a complete vehicle model. Results of these experiments reveal that our established criteria prove useful for predicting whether actual rollover occurs or not.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.11
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• pp.4643-4648
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• 2010

In this study, $CO_2$ absorption properties at high pressure condition that can apply pre-combustion $CO_2$ capture were investigated for physical sorbent such as PEG, DMSO, and Sulfone. The $CO_2$ Solubility, regeneration, and initial absorption rate with temperature and pressure were measured using batch type stirred cell contactor. The PEG showed the highest $CO_2$ solubility and initial absorption rate. It can be found that all the physical sorbents used in this experiments were almost completely regenerated at various temperature and pressure.

• The Journal of Korean Physical Therapy
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• v.31 no.5
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• pp.328-332
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• 2019

Purpose: This study examined the effects of transcranial direct current stimulation (tDCS) on the static balance ability of patients with back pain. Methods: The subjects comprised of 30 males and females in their 20s, who were divided into two groups with and without tDCS. The balance posture ratio score was calculated to determine the changes in balance ability before and after the application of tDCS using balance equipment. A paired t-test was conducted to determine the changes over time, and an independent t-test was performed to determine the changes between the groups. The significance level was set to ${\alpha}=0.05$. Results: A significant difference in the changes in the static balance ability of CTDCSG between before and after applying tDCS was observed while the subjects' eyes were open (p<0.05). A comparison between the groups after the experiments revealed significantly increased changes in CTDCSG compared to STDCSE (p<0.05). The changes in static balance ability were not significant when the subjects' eyes were closed (p>0.05). Conclusion: The application of tDCS positively changed the static balance ability of patients with back pain. The results of this study showed that tDCS could be used as an intervention to increase the static balance ability of patients with back pain in the clinical field. The study results could be used further as foundational data for future studies on tDCS.

• The Journal of Korean Physical Therapy
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• v.33 no.5
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• pp.258-263
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• 2021

Purpose: Myofascial syndrome is a chronic muscle pain caused by repetitive motions with stress-related muscle tension. This study aimed to investigate the validity and reliability of the evidence for diagnosing myofascial pain syndrome in trapezius muscle using a pressure algometer and surface electromyography. Methods: The experiments were performed using a total of 10 subjects, and the target locations were determined by means of a pressure algometer in the right upper trapezius muscle. The part with the lowest pain value as the trigger point and the part with the highest pain value as the non-pain trigger point were selected for measuring the locations. The median frequency and average frequency were measured in those locations with electromyography. To check the muscle fatigue, the upper trapezius muscle was moved up and down for 2 seconds at 5-second intervals in 30 seconds. The measured values were evaluated using the independent paired t-test and MannWhitney U-test. Results: The median frequency at the non-trigger point (13.7) was significantly higher than that at the trigger point (7.3). Furthermore, the mean frequency (14.7) at the non-trigger point was significantly higher than that at the trigger point (6.3). Conclusion: The results showed the correlations between the trigger points of the muscle pain and frequency analysis of surface electromyography. Thus, this study may be possible to use as a diagnostic tool for myofascial pain syndrome.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.31 no.6
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• pp.1279-1290
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• 2021

As vehicle technology has grown, autonomous driving that does not require driver intervention has developed. Accordingly, CAN security, an network of in-vehicles, has also become important. CAN shows vulnerabilities in hacking attacks, and machine learning-based IDS is introduced to detect these attacks. However, despite its high accuracy, machine learning showed vulnerability against adversarial examples. In this paper, we propose a adversarial CAN frame generation method to avoid IDS by adding noise to feature and proceeding with feature selection and re-packet for physical attack of the vehicle. We check how well the adversarial CAN frame avoids IDS through experiments for each case that adversarial CAN frame generated by all feature modulation, modulation after feature selection, preprocessing after re-packet.