• Journal of the Institute of Electronics Engineers of Korea SP
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• v.48 no.6
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• pp.77-87
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• 2011

In this paper, we propose a disparity correction technique to reduce the inherent visual discomfort while watching stereoscopic videos. The visual discomfort must be solved for commercial 3D display systems to provide natural stereoscopic videos to human eyes. The proposed disparity correction technique consists of horizontal and vertical disparity corrections. The horizontal disparity correction is implemented by controlling the depth budget of stereoscopic video using the geometric relations of a stereoscopic camera system. In addition, the vertical disparity correction is implemented by using a feature-based stereo matching algorithm. Conventional vertical disparity corrections have been done by only using camera calibration parameters, which still cause systematic errors in vertical disparities. In this paper, we minimize the vertical disparity as small as possible by using a feature-based correction algorithm. Through the comparisons of conventional feature-based correction algorithms, we analyze the performance of the proposed technique.

• Women's Health Nursing
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• v.24 no.2
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• pp.163-173
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• 2018

Purpose: To identify factors influencing psychosocial adjustment in patients with surgical removal of benign breast tumor. Methods: With a survey design, data were collected using the Psychosocial Adjustment to Illness Scale-Self Report (PAIS-SR), Body Image Scale, Physical Discomfort Scale, and Family Support Scale with patients who had had surgical removal of a benign breast tumor from September to November 2017. Data were analysed with descriptive statistics, t-test, ANOVA, Pearson's correlation coefficients, and stepwise multiple regression. Results: The mean scores for physical discomfort, body image, family support, and psychosocial adjustment were $1.57{\pm}0.51$, $0.37{\pm}0.64$, $3.62{\pm}0.67$, and $4.00{\pm}0.45$, respectively. Family support, body image, physical discomfort, number of surgical removal of benign breast tumor (twice), and cancer insurance status (yes) were verified as factors influencing psychosocial adjustment. These factors accounted for 57.4% of psychosocial adjustment. Conclusion: In this study, family support, body image, and physical discomfort were identified as significant predictors of psychosocial adjustment. Therefore, this study can be used as fundamental data to develop nursing intervention strategies in order to increase psychosocial adjustment in patients with surgical removal of a benign breast tumor.

• The Korean Journal of Pain
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• v.30 no.4
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• pp.265-271
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• 2017

Background: Health care services effort to provide alternative cardiac rehabilitation (CR) models to serve patients according to their preferences and needs. So, the present study aimed to assess and compare the effects of hospital-based and hybrid CR programs on chest pain intensity and discomfort in cardiac surgery patients. Methods: In this prospective study, 110 cardiac surgery patients were invited to the CR department of a hospital in the western part of Iran between March and July 2016. Patients were divided into two groups: hospital-based and hybrid CR. The hospital-based program included 26 sessions, and the hybrid program included 10 training sessions and exercise. The Brief Pain Inventory and Pain Discomfort Scale were used as research instrument, and data were analyzed using the paired t-test and ANCOVA. Results: The results indicated that both hospital-based and hybrid CR are effective in reducing the chest pain intensity and discomfort of cardiac surgery patients (P < 0.05). In addition, the comparison of scores before and after treatment using ANCOVA shows that no significant differences were observed between the two programs (P > 0.05). Conclusions: Traditional hospital-based CR delivery is still the first choice for treatment in developing countries. However, hybrid CR is as effective as a hospital-based program in reducing pain components and it includes only 38% of the total cost in comparison to hospital-based delivery. So, we recommend using hybrid CR according with the recommendations of American Heart Association about using CR for the management of angina symptoms.

• Korean Journal of Human Ecology
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• v.19 no.4
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• pp.655-665
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• 2010

This study analyzed the effects of skinny jean on women's health by questionnaire survey and measuring the pressure experienced under the clothing and participants' subjective view of the pressure level. The average size women in their 20s' waists is 26 inches and so three pairs of jeans were prepared and worn by 4 female participants. A survey was conducted to investigate how often participants wear skinny jeans and whether they had had any feelings of discomfort as a result of this. Participants responded that they hadexperienced middle to high levels of discomfort due to the high pressure inside skinny jeans. For the maximum value of clothing pressures, jean f2 at the part of buttocks showed $48.7gf/cm^2$. The pressure inside the clothing was found to be highest around the buttocks followed by the knees and finally the belly. The mean values of 7 measuring parts are different according to the jean type; f3 $20.8gf/cm^2$ > f2 $16.4gf/cm^2$ > f1 $15.5gf/cm^2$, which is corresponding to the order of pressure sensation, but not corresponding to the order of ease amount of clothing pattern: f2 > f3 > f1. Mean pressure values were also measured according to the body posture: they were found to by highest when sitting on a chair (21.3gf/$cm^2$), second highest when sitting on the floor ($19.2gf/cm^2$) and lowest when standing ($15.0gf/cm^2$). This is not always same to the order of participants subjective perceptions of the pressure, which is, they estimated pressure to be highest when sitting on the floor followed by sitting on a chair and lowest in a standing position.

• Journal of Periodontal and Implant Science
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• v.47 no.4
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• pp.240-250
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• 2017

Purpose: The aim of this study was to analyze the prevalence and risk indicators of peri-implantitis in Korean patients with history of periodontal disease. Methods: A total of 444 patients with 1,485 implants were selected from patients who had been treated at the Department of Periodontology, Chonbuk National University Dental Hospital between July 2014 and June 2015. A group with a history of peri-implantitis (HP) (370 patients with 1,189 implants) and a group with a current peri-implantitis (CP) (318 patients with 1,004 implants) were created based on the radiographic and clinical assessments of implants. The prevalence of peri-implantitis was calculated at both the patient and implant levels. The influence of risk variables on the occurrence of peri-implantitis was analyzed using generalized estimating equations analysis. Results: The prevalence of peri-implantitis in the HP and CP groups ranged from 6.7% to 19.7%. The cumulative peri-implantitis rate in the HP group estimated with the Kaplan-Meier method was higher than that in the CP group over the follow-up period. Among the patient-related risk variables, supportive periodontal therapy (SPT) was the only significant risk indicator for the occurrence of peri-implantitis in both groups. In the analysis of implant-related variables, implants supporting fixed dental prosthesis (FDP) and implants with subjective discomfort was associated with a higher prevalence of peri-implantitis than single implants and implants without subjective discomfort in the HP group. The presence of subjective discomfort was the only significant implant-related variable predictive of peri-implantitis in the CP group. Conclusions: Within the limitations of this study, the prevalence of peri-implantitis in Korean patients with a history of periodontal disease was similar to that reported in other population samples. Regular SPT was important for preventing peri-implantitis. Single implants were found to be less susceptible to peri-implantitis than those supporting FDP. Patients' subjective discomfort was found to be a strong risk indicator for peri-implantitis.

• Safety and Health at Work
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• v.11 no.2
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• pp.207-214
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• 2020

Background: Prolonged sitting at work can lead to adverse health outcomes. The health risk of office workers is an increasing concern for the society and industry, with prolonged sitting work becoming more prevalent. Objective: This study aimed to explore the variation in muscle activities during prolonged sitting work and found out when and how to take a break to mitigate the risk of muscle symptoms. Methods: A preliminary survey was conducted to find out the prevalence of muscle discomfort in sedentary work. Firstly, a 2-h sedentary computer work was designed based on the preliminary study to investigate the variation in muscle activities. Twenty-four participants took part in the electromyography (EMG) measurement study. The EMG variations in the trapezius muscle and latissimus dorsi were investigated. Then the intervention time was determined based on the EMG measurement study. Secondly, 48 participants were divided into six groups to compare the effectiveness of every break type (passive break, active break of changing their posture, and stand and stretch their body with 5 or 10 mins). Finally, data consisting of EMG amplitudes and spectra and subjective assessment of discomfort were analyzed. Results: In the EMG experiment, results from the joint analysis of the spectral and amplitude method showed muscle fatigue after about 40 mins of sedentary work. In the intervention experiment, the results showed that standing and stretching for 5 mins was the most effective break type, and this type of break could keep the muscles' state at a recovery level for about 30-45 mins. Conclusions: This study offers the possibility of being applied to office workers and provides preliminary data support and theoretical exploration for a follow-up early muscle fatigue detection system.

• Journal of the Korean Society for Railway
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• v.19 no.5
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• pp.576-584
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• 2016

In this study, we measured the air tightness of a train using pressure variation in tunnels. To estimate the air tightness of a train is essential to comprehend the pressure variation of the cabin because air tightness is strongly related with ear discomfort. If we can determine the air tightness, we can predict the pressure variation of the cabin. Also, ear discomfort is a problem that can be caused in a high speed train, as well as in Korea's Great Train Express. In this study, we compared the various international standards for ear discomfort and estimated the air tightness of each vehicle based on experimental data obtained using the ITX, KTX and KTX-sancheon(honam) vehicles. The internal pressure variation of the trains is numerically calculated using the air tightness value. The results are good compared to the experimental results. Instead of flap type ventilation, in the future, continuous ventilation equipment will be needed for speed-up.

• Journal of the Ergonomics Society of Korea
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• v.30 no.5
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• pp.671-681
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• 2011

Objective: The purpose of this study is to compare the workload level at each lower limbs posture and suggest the ergonomic workstation guideline for working period by evaluating the imbalanced lower limbs postures from the physiological and psychophysical points of view. Background: Many workers like welders are working in various imbalanced lower limbs postures either due to the narrow working conditions or other environmental conditions. Method: Ten male subjects participated in this experiment. Subjects were asked to maintain 3 different lower limbs postures(standing, squatting and bending) with 3 different working conditions(balanced floor with no scaffold, imbalanced floor with 10cm height of scaffold, and imbalanced floor with 20cm height of scaffold). EMG data for the 4 muscle groups(Retus Femoris, Vastus Lateralis, Tibialis Anterior, Gastrocnemius) from each lower limbs posture were collected for 20 seconds every 2 minutes during the 8 minutes sustaining task. Subjects were also asked to report their discomfort ratings of body parts such as waist, upper legs, lower legs, and ankle. Results: The ANOVA results showed that the EMG root mean square(RMS) values and the discomfort ratings(CR-10 Rating Scale) were significantly affected by lower limbs postures and working time(p<0.05). The correlation was analyzed between the EMG data and the discomfort ratings. Also, prediction models for the discomfort rating for each posture were developed using physical condition, working time, and scaffold height. Conclusion: We strongly recommend that one should not work more than 6 minutes in a standing or squatting postures and should not work more than 4 minutes in a bending posture. Application: The results of this study could be used to design and assess working environments and methods. Furthermore, these results could be used to suggest ergonomic guidelines for the lower limbs postures such as squatting and bending in the working fields in order to prevent fatigue and pain in the lower limbs body.

• Journal of the Korean Society for Precision Engineering
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• v.29 no.7
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• pp.705-710
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• 2012

Research involving discomfort or pain related to haptic vibratory stimulation the for prosthesis users of myoelectrical hand is very lacking. Our objective of this study was to evaluate the displeasure and sensitivity of areas in forearm using vibration stimulation system between upper limb amputees and non-amputees. Twenty transradial amputees and forty non-amputees (20 youth, 20 elderly) were involved. We set up custom-made vibration stimulation system including eight actuators (4 medial parts and 4 lateral parts) and GUI-based acquisition system, to investigate changes of residual somatosensory sensibility and displeasure at proximal 25% of forearm. Eight vibration actuators were attached to the circumference of proximal 25% point of forearm at regular intervals. Sensitivity tests were used to stimulate the 120Hz and discomfort experiment was used to 37 ~ 223Hz. The subjective responses were evaluated by 10 point scale. The results showed that both groups were similar in sensitive areas. Response at around of radius was most sensitive than other areas in all subjects. Elderly group do not appear discomfort of vibrotactile; however, youth group and amputee presented discomfort of vibrotactile. Prosthesis with a vibrotactile feedback system should be developed considering the sensitivity. Furthermore, Future studies should investigate the scope of application of that principle.

• Journal of the Korea Convergence Society
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• v.12 no.12
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• pp.491-498
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• 2021

This study is presented as evidence for developing a health education program to prevent lower extermity circulatory system problems among nurses's health problem by identifying the effects of taping therapy on lower extermites discomfort and fatigue for nurses who stand for long periods of time. The study method is a similar experimental study using a nonequivalent control group pretest-posttest design in which taping therapy was applied to female nurses who work day shifts for 5 consecutive days in an orthopedic surgery ward. Data collection was from November 2 to December 18, 2020, and a total of 60 nurses, 30 in the experimental group and 30 in the control group, were recruited from two orthopedic surgery hospitals located in B city. The data were analyzed by chi-square test, t-test and paired t-test using the SPSS WIN 22.0 program. As a result of the study, the experimental group had lower extermities discomfort(t=-1.27, p=<.001) and fatigue score(t=-0.60, p=<.001) than the control group, and it was confirmed that there was a statistically significant effect. It has been proven that taping therapy is a very effective nursing intervention.