• Journal of the Korea Institute of Military Science and Technology
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• v.18 no.6
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• pp.789-796
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• 2015

Fighter pilot's ability to maintain both mental and physical capabilities in highly stressful situations is important for aviation safety as well as mission performance because pilot may confront frequently unexpected physical and psychological stimulation. Cumulative psychological stress and physical fatigue can be causes of mood distortion, declined alertness, and can lead to reduction of combat capability. We have investigated bio-signals and performance tests to monitor stress and fatigue levels, and developed a system to evaluate aviation mission suitability before flight. This study elucidated that stress and fatigue level of pilot can be monitored by psychomotor cognitive test(PCT) and heart rate variability(HRV), and that the best of reference for aviation mission suitability was confidential interval obtained from cumulative data of individuals. The system to evaluate aviation mission suitability was constructed with measuring part with PCT and HRV and control part with DB and algorithm.

• Journal of Physiology & Pathology in Korean Medicine
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• v.27 no.5
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• pp.587-593
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• 2013

Exhaustion syndrome(虛勞) became broadly experienced symptoms in Korean population. In this work, we carried out a systematic literature review on exhaustion syndrome(ES) and chronic fatigue. We searched through the databases Koreanstudies Information Service System, Oriental Medicine Advanced Searching Integrated System, DataBase Periodical Information Academic for the articles published between 1994 and 2013, with the keywords 'exhaustion syndrome(虛勞)', 'consumption(虛損)', 'overexertion syndrome(勞倦)', 'fatigue', 'chronic fatigue' and 'degree of fatigue'. Among the first-run rough-searched 602 articles, we narrowed down the scope within the field of Oriental medicine (126 articles), and finally selected 28 articles appropriate to the intended research field; the selected articles were categorized by literature study(7 papers), clinical treatment (7), clinical diagnosis (5), treatment effects of herbal medicine (2), diagnosis in Sasang medicine and treatment effect of dry cupping therapy (2), and questionnaire-based diagnosis (5). We found that the overall research level on ES remained in the preliminary stages, and more efforts are needed in the field of terminology definition and standardization of diagnosis, and treatment efficacy validation beyond muscle fatigue. Finally, to develop reliable diagnostic devices on ES, we proposed a study design that included the development of objective ES diagnostic indicators and a clinical validation procedure.

• Journal of Physiology & Pathology in Korean Medicine
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• v.29 no.5
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• pp.409-415
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• 2015

This study compared the heart rate variability tests of healthy college students and chronic fatigue patients for 2 years. Study subjects were idiopathic chronic fatigue patients who carried out the HRV tests and students conducted HRV test when health screening test. Study subjects were 250 people, 104 people and men (41.6%), women were 146 patients (58.4%). In patient group, the autonomic nervous system activity was decreased, the activity of the sympathetic nerve and the parasympathetic nerve were significantly reduced compared to the control group(Patient:84.17±16.27, Control:98.33±17.28). Regardless of gender, patient group's autonomic nervous system activity was decreased, the activity of the sympathetic nerve and the parasympathetic nerve were significantly reduced, compared to the control group(Patient Female:84.17±16.27, Patient Male:84.07±14.96/Control Female:98.33±17.28, Control Male:96.45±16.92). Even though same ages, patient group's autonomic nervous activity was reduced compared to control group(Patient:89.36±12.43, Control:97.39±16.91). Fatigue patients' activity of the sympathetic nerve and the parasympathetic nerve were significantly reduced, regardless of the fact that activity of the sympathetic nerve is increased and the parasympathetic nerve is decreased in stress state like an impassioned injury(七情傷). Therefore HRV test is useful to diagnose Fatigue from this study.

• Journal of Physiology & Pathology in Korean Medicine
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• v.32 no.2
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• pp.126-133
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• 2018

The aim of this survey is to investigate the current state of pattern identification, treatment and management on chronic fatigue in the Korean medicine. From May 25, 2017 to June 7, we distributed contents of questionnaires to 17,992 Korean medical doctors via e-mail, and then received answers from 329 people. The surveys were conducted by a specialized research organizations. Researchers were blinded to the participant's personally identifiable information or whether they participated in the investigation. In Korea, almost Korean medicine doctors (94.5%) used pattern identification in the treatment of chronic fatigue patients. The main diagnostic methods were visceral (38.5%), qi-blood-fluid-humor (32.3%), and sasang constitutional pattern identification (14.3%). The high-frequent therapy were herbal medicine (37.0%), acupuncture (27.9%), moxibustion (11.7%), and cupping (8.6%). The primary goals of treatment were Improvement and relaxation of stress condition (18.1%), improvement of quality of life (13.1%), increase of functional vitality (34.0%), and fatigue management (23.3%). The key factors affecting treatment outcomes were the patient's aggressiveness in treatment (23.5%) and his/her lifestyle and environment(22.7%). This study was a pioneering research for chronic fatigue on the aspect of medical service provider in the Korean medicine. We hope that this study can be used as a basis for developing a more appropriate and reasonable practice guidelines for chronic fatigue.

• Fashion & Textile Research Journal
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• v.13 no.5
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• pp.752-758
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• 2011

In this paper, experiments to develop working clothes and evaluated, including the current and material-improved working clothes in relation to physiological functionality measurement. Experiments were conducted on subjects after wearing working clothes in an climate chamber, and the thermo-physiological response, such as human body temperature, micro-climate within the clothes, blood pressure, heart rate were measured. In this manner, the physiological functionality of improved working clothes was compared with that of current working clothes and evaluated. The summary of obtained results is as follows: For physiological functionality evaluation through material-improved working clothes, P working clothes showed significantly lower rectal temperature than C working clothes. For mean skin temperature, P's skin temperature was significantly higher than C's in the second half of the experiment. P working clothes's temperature around the thighs in Micro climate was significantly lower than that of the C working clothes. Also, humidity within the clothes showed similar trends. During the exercise period, C working clothes showed higher blood pressure than P, but P showed higher heart rates than C. Also, the oxygen uptake amount was higher in C than P during the exercise period, it explains that the energy consumption amount of P working clothes was smaller than that of C working clothes. Of the subjective evaluation, for temperature sensation, workers wearing P working clothes felt cooler. For humidity, C working clothes showed more humidity. For comfort, P working clothes were better, and for sense of fatigue, workers felt less tired wearing P working clothes. From results above, we can see that physiological functionality improved in the material-improved working clothes in the working clothes for construction site workers. The improvement of working clothes through functionality improvements not only will provide personal pleasantness to constriction site workers, but will also generate efficiency and productivity improvements at construction sites. All in all, the continuous study of functionality improvements in working clothes taking into consideration the human body's physiological responses is required.

• Journal of Korean Academy of Nursing
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• v.36 no.2
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• pp.310-320
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• 2006

Purpose: The purpose of this study was to investigate the effects of a rehabilitation program on physical health, physiological indicators and quality of life in breast cancer mastectomy patients. Methods: The subjects included thirty-one patients with breast cancer(17 in the experimental group and 14 in the control group). The subjects in the experimental group participated in a rehabilitation program for 10 weeks, which was composed of an exercise program, teaching, counseling and support for 2 sessions per week. Results: There was a significant increase in flexion, internal rotation and external rotation but no significant increase in extension in the experimental group compared to the control group. The total cholesterol, triglyceride, HDL, LDL, and CD56 in the experimental group compared to the control group was not significantly decreased after the rehabilitation program. Compared to the control group, quality of life in the experimental group was significantly improved and fatigue in that group was significantly decreased after the rehabilitation program. Conclusion: The 10-week rehabilitation program showed a large affirmative effect on physical health, physiological indicators and quality of life in breast cancer mastectomy patients.

• Journal of Ginseng Research
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• v.35 no.3
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• pp.331-338
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• 2011

Red ginseng (RG, the extract of Panax ginseng Meyer) has various biological and psychological activities and may also alleviate fatigue-related disorders. The present study was undertaken to evaluate what kind of fatigue red ginseng alleviate. Animals were orally administered with 50, 100, 200, 400 mg/kg of RG for 7 days. Before experiments were performed. Physiological stress (swimming, rotarod, and wire test) are behavioral parameters used to represent physical fatigue. Restraint stress and electric field test to a certain degree, induce psychological fatigue in animals. Plasma concentration of lactate and corticosterone (CORT) were also measured after these behavioral assays. RG supplementation (100 mg/kg) increased movement duration and rearing frequency of restrainted mice in comparison with control. 100 and 200 mg/kg of RG increased swimming time in cold water ($8{\pm}4^{\circ}C$) while at 100 mg/kg, RG increased electric field crossing over frequencies. 50, 100 and 200 mg/kg RG prolonged running time on the rotarod and at 100 mg/kg, it increased balancing time on the wire. RG at those doses also reduced falling frequencies. RG supplementation decreased plasma CORT levels, which was increased by stress. Lactate levels were not significantly altered. These results suggest that RG supplementation can alleviate more the damages induced by psychological than physical fatigue.

• Journal of the Ergonomics Society of Korea
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• v.33 no.2
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• pp.143-153
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• 2014

Objective: The aim of this study is to investigate the effects of trunk-forearm supported sitting on trunk flexion angle, trunk extensor fatigue and seat contact pressure. Background: The relationship between sitting posture and musculoskeletal disorders of the trunk extensor fatigue and seat contact pressure has been documented. The trunk-forearm support type ergonomic chair was devised from the fact that trunk-forearm support has been reported to reduce trunk extensor activity and discomfort. Method: Using three different sitting postures, upright ($P_1$), trunk-forearm supported ($P_2$) and normal sitting ($P_3$), six healthy subjects participated in the study. Motion capture system was used to collect head and trunk flexion angle, and surface electromyography (sEMG) was used to collect myoelectric signal of upper trapezius, lower trapezius, erector spinae, multifidus, and pressure mat system was used to measure seat contact pressure. Results: When trunk and forearm were supported by the ergonomic chair, higher head flexion angle showed upright > trunk-forearm supported > normal in order, and muscle fatigue showed less than upright and normal sitting. Mean seat contact pressure decreased 19% than upright sitting. But muscle fatigue was not affected by each condition. Conclusion: Trunk-forearm supported sitting of the ergonomic chair showed positive effect in respect of trunk and head flexion angle, trunk extensor fatigue, seat contact pressure. To acquire comprehensive understanding of the effectiveness of the ergonomic chair, further studies such as anatomical effects from measurement of external applied loading effect to the body from interface pressure analysis are required. Application: The results of the publishing trend analysis might help physiological effects of trunk-forearm support type chair.

• Journal of Physiology & Pathology in Korean Medicine
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• v.34 no.3
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• pp.117-125
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• 2020

The purpose of this review is to confirm whether Soyo-san (Xiaoyao-san) and its modifications is effective on alleviating clinical symptoms in chronic fatigue syndrome (CFS) patients. We collected clinical trials (randomized controlled trial, quasi-randomized controlled trial, controlled clinical trial) to investigate the effects of Soyo-san and its modifications on general symptoms, fatigue, depression and anxiety in CFS patients. The databases used for data retrieval were Pubmed, Central Cochrane, Embase, CNKI, CQVIP, Wanfang, CiNii, OASIS, RISS, and Koreamed. We performed selection/exclusion process from the found studies to conform with prespecified criteria, and assessed the final included trials according to the Cochrane risk of bias tool. The included studies were classified based on the interventions in experimental and control group. Eight randomized controlled trials and one controlled clinical trial (total 921 participants) were eligible and their results were synthesized in the meta analysis. The synthesis showed a considerable effect of Soyo-san and its modifications on improvement of general symptoms (relative risk 0.27 [95% CI 0.19 to 0.39], Z=7.03, P<0.00001; I2=0%) and fatigue severity (SMD -1.20 [95% CI -1.46 to -0.93], Z=8.78, P<0.00001; I2=52%) in CFS patients, while Effect on depression and anxiety were inconclusive. We found that Soyo-san and its modifications were effective for improvement of general symptoms and fatigue severity in CFS post-treatment.

• The Journal of Advanced Prosthodontics
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• v.13 no.5
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• pp.269-280
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• 2021

PURPOSE. The objective of this study was to evaluate the effect of thickness reduction and fatigue on the failure load of monolithic zirconia crowns. MATERIALS AND METHODS. 140 CAD-CAM fabricated crowns (3Y-TZP, inCorisTZI, Dentsply-Sirona) with different ceramic thicknesses (2.0, 1.5, 1.0, 0.8, 0.5 mm, respectively, named G2, G1.5, G1, G0.8, and G0.5) were investigated. Dies of a mandibular first molar were made of composite resin. The zirconia crowns were luted with a resin composite cement (RelyX Unicem 2 Automix, 3M ESPE). Half of the specimens (n = 14 per group) were mouth-motion-fatigued (1.2 million cycles, 1.6 Hz, 200 N/ 5 - 55℃, groups named G2-F, G1.5-F, G1-F, G0.8-F, and G0.5-F). Single-load to failure was performed using a universal testing-machine. Fracture modes were analyzed. Data were statistically analyzed using a Weibull 2-parameter distribution (90% CI) to determine the characteristic strength and Weibull modulus differences among the groups. RESULTS. Three crowns (21%) of G0.8 and five crowns (36%) of G0.5 showed cracks after fatigue. Characteristic strength was the highest for G2, followed by G1.5. Intermediate values were observed for G1 and G1-F, followed by significantly lower values for G0.8, G0.8-F, and G0.5, and the lowest for G0.5-F. Weibull modulus was the lowest for G0.8, intermediate for G0.8-F and G0.5, and significantly higher for the remaining groups. Fatigue only affected G0.5-F. CONCLUSION. Reduced crown thickness lead to reduced characteristic strength, even under failure loads that exceed physiological chewing forces. Fatigue significantly reduced the failure load of 0.5 mm monolithic 3Y-TZP crowns.