• Physical Therapy Korea
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• v.30 no.1
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• pp.8-14
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• 2023

Background: Excessive hamstring (HS) activation due to the weakness of the gluteus maximus (GM) causes pain in the hip joint. A single-leg deadlift is a hip extensor exercise, especially GM, that includes functional movements in daily life and complex multi-joint training. In single-leg deadlift, the muscle activity depends on the forward trunk lean angle, and it's necessary to study which muscles are used dominantly depending on the angle. Objects: The purpose of this study was to compare the effect on the muscle activity of the GM and HS during single-leg deadlift according to different forward trunk lean angles and the ratio of the GM vs HS (GM/HS). Methods: Twenty-one healthy female participants were recruited. The muscles activities of the GM, HS and the GM/HS ratio were measured through electromyography during single-leg deadlift according to three condition of forward trunk lean angles (30°, 60°, and 90°). Results: The GM and HS activities significantly differed among three conditions (p < 0.05). GM/HS ratio was significantly higher at 30° and 60° of forward trunk lean compared to 90°. Moreover, the GM activity was significantly higher at 60° of forward trunk lean than at 30° (p < 0.05). Conclusion: The single-leg deadlift at 60° of forward trunk lean is a proper GM muscle strengthening exercise.

• Nuclear Engineering and Technology
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• v.56 no.4
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• pp.1472-1479
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• 2024

Cyber-Physical Energy Systems (CPESs) integrate cyber and hardware components to ensure a reliable and safe physical power production and supply. Renewable Energy Sources (RESs) add uncertainty to energy demand that can be dealt with flexible operation (e.g., load-following) of CPES; at the same time, scenarios that could result in severe consequences due to both component stochastic failures and aging of the cyber system of CPES (commonly overlooked) must be accounted for Operation & Maintenance (O&M) planning. In this paper, we make use of Deep Reinforcement Learning (DRL) to search for the optimal O&M strategy that, not only considers the actual system hardware components health conditions and their Remaining Useful Life (RUL), but also the possible accident scenarios caused by the failures and the aging of the hardware and the cyber components, respectively. The novelty of the work lies in embedding the cyber aging model into the CPES model of production planning and failure process; this model is used to help the RL agent, trained with Proximal Policy Optimization (PPO) and Imitation Learning (IL), finding the proper rejuvenation timing for the cyber system accounting for the uncertainty of the cyber system aging process. An application is provided, with regards to the Advanced Lead-cooled Fast Reactor European Demonstrator (ALFRED).

• Journal of Web Engineering
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• v.19 no.2
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• pp.139-166
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• 2020

The functions, capabilities, and effects produced by the application services of cyber physical systems (CPS) are usually consumed by users performing their daily activities in a variety of environmental conditions. Thus, it is critical to ensure that those systems neither interfere with human activities nor harm the users involved. In this paper, we propose a framework for testing and verifying the safety and reliability of CPS services from the perspectives of CPS environments and users. The framework provides an environmentaware testing method by which the efficiency of testing CPS services can be improved by prioritizing CPS environments and by applying machinelearning techniques. The framework also includes a metric by which we can automate the test of the most effective services that deliver effects from physical devices to users. Additionally, the framework provides a computational model that assesses mental workloads to test whether a CPS service can cause cognitive depletion or contention problems for users. We conducted a series of experiments to show the effectiveness of the proposed approaches for ensuring the safety and reliability of CPS application services during the development and operation phases.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.29 no.1
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• pp.41-52
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• 2023

Background: Bulgarian split squat (BSS) is beneficial to improve dynamic balance ability and muscle activity of lower extremities, however its effects have not been fully investigated. Therefore, this study aimed to compare changes in dynamic balance ability and muscle properties according to various modifications of BSS exercises. Methods: Thirty healthy male volunteers participated in this study, and they were randomly divided into three different groups. The subjects performed the BSS exercise either on a stable surface with the eyes opened (n=10) or eyes closed (n=10), and on an unstable support plane with eyes opened (n=10) conditions, respectively. Dynamic balance ability was measured via Biodex balance system under the eyes-opened and closed conditions. Additionally, muscle properties of the rectus femoris (RF), vastus medialis (VM) and vastus lateralis (VL) were evaluated. Results: Dynamic balance ability did not show the significant differences among the groups that performed the BSS exercises. However, in the Unstable group, there were significant differences in the overall stability index and anterior posterior stability index under the eyes-closed condition between pre-exercise and post-exercise. In comparison of muscle properties according to the groups, RF muscle showed a significant difference in amount of change of elasticity (p=.038). Additionally, there were significant changes in post measurements of VM muscle tone (p=.016), stiffness (p=.012) and elasticity (p=.002). VL muscle, however had no significant differences in muscle properties. Conclusion: These results indicate that BSS exercises could induce the alteration of RF and VM muscle properties, in particular VM muscle which is susceptible to weakness. Thus, BSS could be applied in various ways as an effective rehabilitation exercise.

• The Journal of the Convergence on Culture Technology
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• v.4 no.4
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• pp.123-133
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• 2018

This study aimed to suggest basic data required to improve the awareness of physical therapy and examine physical therapists' awareness of the independent establishment of physical therapy clinics. To do so, 175 physical therapists in Gyeongnam areas were surveyed. Their general characteristics were statistically analyzed using SPSS 10.0, and their current workplace, working conditions and job satisfaction were analyzed using chi square distributions. The awareness of independent establishment was analyzed using the Excel program. The statistical significance (a) in this study was set at 0.05. Their interest in physical therapy was surveyed by gender, and 52.2% of males showed interest, higher than that of females. The satisfaction level of those who work in general hospitals with self-development was 32.8%, higher than that of those who work in clinics. To the question about independent establishment, 83.4% agreed to independent establishment, and 57.5% answered that the first thing to do before independent establishment is acquiring professional theoretical knowledge and clinical treatment skills. In terms of the areas of establishment, 45.2% answered physical therapy for the musculoskeletal system, and 39.7% answered that the awareness of doctors is the biggest obstacle to independent establishment. It will be necessary to ensure physical therapists acquire professional theoretical knowledge and clinical treatment skills and to improve awareness between physical therapists and doctors. In addition, it is considered that departments related to physical therapy need to be unified as a four-year course, and the independent establishment of physical therapy clinics is required to be legalized.

• Physical Therapy Korea
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• v.25 no.1
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• pp.22-30
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• 2018

Background: Improvement of lumbo-pelvic stability can reduce the compensatory action of the quadratus lumborum (QL) and selectively strengthen the gluteus medius (GM) during side-lying hip abduction (SHA). There are abdominal draw-in maneuver (ADIM) and abdominal bracing (AB) as active ways, and pelvic compression belt (PCB) as a passive way to increase of lumbo-pelvic stability. It is necessary to compare how these stabilization methods affect the selective strengthening of the GM. Objects: To investigate the effects of ADIM, AB, and PCB during SHA on the electromyography (EMG) activity of the GM, QL, external oblique (EO) and internal oblique (IO), and the GM/QL EMG activity ratio. Methods: A total of 20 healthy male adults participated in the study. The subjects performed three conditions in side-lying in random order: SHA with ADIM (SHA-ADIM), SHA with AB (SHA-AB), and SHA with PCB (SHA-PCB). To compare the differences among the three conditions, the EMG activities of the GM, QL, EO and IO, and GM/QL EMG activity ratio were analyzed using one-way repeated ANOVA. Results: The EMG activity of the QL was significantly higher in SHA-AB than in SHA-ADIM and SHA-PCB. The GM/QL activity ratio was significantly higher in SHA-PCB than in SHA-ADIM and SHA-AB. In addition, the figure for SHA-ADIM was significantly higher than that for SHA-AB. In the case of the EO, the figure for SHA-AB was significantly higher than corresponding values for the other two conditions. The figure for SHA-ADIM was significantly higher than that for SHA-PCB. The EMG activity of the IO was significantly higher in SHA-AH than in SHA-PCB. Conclusion: It can be suggested that wearing the PCB can more selectively strengthen the GM than to perform ADIM and AB during SHA. In addition, the ADIM can be recommended when there is a need to strengthen abdominal muscles during SHA.

• Journal of Digital Convergence
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• v.15 no.7
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• pp.297-306
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• 2017

The study was performed to determine the impact of the gastrocnemius taping with balance training on spasticity and balance ability of the ankle joint. A total of 25 stroke subjects were divided into two groups: a taping with balance training (n=14), a sham taping with balance training (n=11). Spasticity assesment was scored by modified ashworth scale. Balance ability assesment was performed by functional reach test (FRT), the timed up & go test (TUG). The stability index (SI), the left-right weight distribution (left-right WD), the toe-heel weight distribution (toe-heel WD) were analyzed in the eyes open conditions(EO) and eyes closed conditions(EC) conditions using by the Tetrax interactive balance system. The experimental group showed a significant improvement in SI, left-right WD and toe-heel WD in the EO and EC, MAS, FRT, TUG. In comparison between the groups, a significant improvement was detected in FRT, TUG, SI and left-right WD in the EO, and left-right WD and toe-heel WD in the EC. It was found out that a short period of balance training with taping is effective on spasticity and balance ability in stroke patients. Therefore, any stroke patient without skin damage is encouraged to use the gastrocnemius taping for balance rehabilitation.

• Journal of Environmental Health Sciences
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• v.31 no.4 s.85
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• pp.266-279
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• 2005

The present study was conducted to analyze the causes of stress on the part of Korean radiological technologists depending on their working environments. For this purpose, 890 questionnaires were distributed to and collected from radiological technologists who were working at 44 general hospitals in 16 cities and provinces of Korea during the period from the mid July to the end of August 2003. The collected data were compared between regions, divided into the capital, metropolitan, medium and small cities, whose results are as follows: 1. As factors affecting working conditions, drinking was found to exert more influence on radiological technologists in small- and medium-sized cities, while loyalty to immediate seniors and organizations was the one producing greater influence on them in metropolitan cities than other cities. Overall, position, job satisfaction and physical condition seemed to have a great effect on them (p<0.001).2. In terms of factors related to their roles, job satisfaction and physical condition played in general a greater role for radiological technologists (p<0.001). Immediate seniors and behavioral conducts were also found to have a lot influence on them (p<0.01).3. As for job conflicts, the kind of medical institutions seemed to exercise a great deal of impact on radiological technologists (p<0.05), while colleagues, immediate seniors, job satisfaction and physical conditions also produced a lot of influence on them as a whole (p<0.001).4. Regarding job autonomy, radiological technologists were found to have been less influenced by position in metropolitan cities and by immediate seniors in the capital city (p<0.01). As a whole, however, age and job satisfaction acted as decisive factors of influence on them (p<0.001). 5. Among factors related to job burden, gender played a bigger role for radiological technologists in metropolitan cities as the kind of medical institutions did in small- and medium-sized cities. Centrally, job satisfaction and behavioral conducts exercised a great impact on them (p<0.001).6. Job stability seemed to be more immensely linked to gender and physical conditions in metropolitan cities whereas position did more in the capital city. In general, how ever, job satisfaction produced a far-reaching (p<0.001).

• Journal of the Korean Society of Clothing and Textiles
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• v.11 no.1
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• pp.51-62
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• 1987

In this study, electrostatic behavior of polyester and nylon fabric treated with anti-static agents were investigated. The effects of the concentration of the agents and curing conditions on the electrostatic charge of the fabrics were studied. And washfastness, lightfastness and physicalproperties of the treated fabrics were also investigated. The results were as follows: 1) Polyethylene glycol alkylester was more effective in antistatic behavior than polyethylene laurylphosphate, and polyester is more effective in anti-static behavior than nylon. 2) Concentration of anti-static agents were suitable in concentration of $4\%$. 3) Glyoxal resin was more effective in anti-static behavior than melamine resin, and it was also good in the retaing anti-static behavior after treatments of lightfastness and washfastness. 4) As the condition of curing treatment, $190^{\circ}C$, 1min. for glyoxal resin and $130^{\circ}C$, 4min. for melamine resin is appropriate. 5) In comparison of anti-static behavior according to treating conditions, the simultaneous treatment was more effective than any other treatments. 6) Change of electrostatic charge of anti-static nylon cloths after treatments of lightfastness and washfastness increased greatly in above 10 laundering time and 20 fade-O-meter time. 7) In physical properties according to concentration of treating agents. decrease of physical properties scarcely appeared in concentration of treating agents $4\~5\%$.

• Journal of the Korean housing association
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• v.25 no.6
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• pp.49-56
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• 2014

In this study, there is a purpose of using the GIS DB built in DEM, by analyzing the physical characteristics of the building site Yangdong village, to determine the spatial structure of the village. In order to understand the targeted spatial structure of Yangdong Village, the building site was analyzed separately by type and position. Through analysis it is clear the selection of building site relates to the slope and aspect that aquires the most solar radiation in Yangdong Village. This study shows that the amount of solar radiation in the terrain is unfavorable in parts of the village because slope and elevation affect the selection of the building site. That is, this village is confirmed to be influenced by solar radiation, according to slope and elevation, based on how the Yangdong Village is configured. And, while overcoming the adverse conditions to make the most, the village is formed according to the natural environmental conditions.