• Journal of the Korean Data and Information Science Society
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• v.17 no.3
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• pp.861-869
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• 2006

Burn-in is a widely used method to improve the quality of products or systems after they have been produced. In this paper, the problem of determining optimal burn-in time for a system which performs given mission is considered. It is assumed that the given mission time is not a fixed constant but a random variable which follows an exponential distribution. Assuming that the underlying lifetime distribution of a system has an eventually increasing failure rate function, an upper bound for the optimal burn-in time which maximizes the probability of performing given mission is derived. The obtained result is also applied to an illustrative example.

• Archives of Plastic Surgery
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• v.50 no.1
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• pp.121-124
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• 2023

With the continuous incorporation of new technologies and advancements in surgical technique, microsurgical procedures around the world have generated a higher success rate and innovative procedures are now possible. In this setting, limitations regarding accessibility and acquisition of medical resources and equipment for these types of operations may be difficult in developing countries. We believe the dexterities of surgeons go beyond the surgical technique, meaning that we are able to use everyday materials to re-create affordable solutions that can be used during surgery in a safe way. This manuscript presents our experience with different surgical instruments and gadgets, developed out of necessity, to improve microsurgical interventions in developing countries.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.5
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• pp.433-442
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• 2020

This study established the relationship between job stress and burn-out syndrome of firefighters. The research targets were 582 firefighters who worked at five fire stations in the D metropolitan city. The survey was conducted using a self-administered questionnaire during the period from July 1st 2019 to September 30, 2019. On the correlation analysis, burn-out showed a significant positive correlation with job stress. On the results of the logistic regression anaylsis, the risk ratio of high levels of burn-out was significantly higher in the very high stress groups than that in the groups with low job stress. According to the multiple regression analysis, the factors having an influence on burn-out were gender, age, the specific level of job career, shift work, the physical burden of work, the sense of satisfaction with the work, consideration for quitting the job and job stress. These findings suggest that the job stress of firefighters is closely related to burn-out. This demands the development and implementation of programs that can properly control and curb the factors of job-stress.

• Archives of Plastic Surgery
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• v.32 no.4
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• pp.408-415
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• 2005

Following a transverse rectus abdominis musculocutaneous(TRAM) flap breast reconstruction, denervated state of the flap causes the flap skin prone to thermal injury, calling for special attention. During the last 5 years, 69 breast reconstruction with 72 free TRAM flaps, were performed. Four out of thesse 69 patients sustained burn injury. Heat sources were a warm bag(n=2), heating pad(n=1) and warming light (n=1). The thermal injuries occured from 2 days to 3 months following the reconstruction. Three patients healed with conservative treatment, but one patient required debridement and skin graft. Initially 3 out of 4 patients with the burn had shown superficial 2nd degree burn with small blebs or bullae. However all 4 patients healed with scars. Mechanism of burn injuries of the denervated flap are known to be resulting from; 1) loss of behavioral protection due to denervation of flap with flap elevation and transfer, 2) loss of autonomic thermoregulatory control with heat dissipation on skin flap vasculature contributing to susceptibility of burn injury. 3) changes of immunologic and normal inflammatory response increasing thromboxane, and a fall in substance P & NGF (nerve growth factor). Including the abdominal flap donor site, sensory recovery of the reconstructed breast varies individually from 6 month even to 5 years postoperatively. During this period, wound healing is delayed, resulting in easier scarring compared to that observed in the sensate skin. Patients should be carefully informed and warned of possible burn injuries and taught to avoid exposure to heat source at least until 3 years postoperatively.

• Archives of Plastic Surgery
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• v.32 no.4
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• pp.403-407
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• 2005

Following a transverse rectus abdominis musculocutaneous(TRAM) flap breast reconstruction, denervated state of the flap causes the flap skin prone to thermal injury, calling for special attention. During the last 5 years, 69 breast reconstruction with 72 free TRAM flaps, were performed. Four out of thesse 69 patients sustained burn injury. Heat sources were a warm bag(n=2), heating pad(n=1) and warming light (n=1). The thermal injuries occured from 2 days to 3 months following the reconstruction. Three patients healed with conservative treatment, but one patient required debridement and skin graft. Initially 3 out of 4 patients with the burn had shown superficial 2nd degree burn with small blebs or bullae. However all 4 patients healed with scars. Mechanism of burn injuries of the denervated flap are known to be resulting from; 1) loss of behavioral protection due to denervation of flap with flap elevation and transfer, 2) loss of autonomic thermoregulatory control with heat dissipation on skin flap vasculature contributing to susceptibility of burn injury. 3) changes of immunologic and normal inflammatory response increasing thromboxane, and a fall in substance P & NGF (nerve growth factor). Including the abdominal flap donor site, sensory recovery of the reconstructed breast varies individually from 6 month even to 5 years postoperatively. During this period, wound healing is delayed, resulting in easier scarring compared to that observed in the sensate skin. Patients should be carefully informed and warned of possible burn injuries and taught to avoid exposure to heat source at least until 3 years postoperatively.

• Proceedings of the Korean Ceranic Society Conference
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• 2003.10a
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• pp.165.1-165
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• 2003

• The Korean Journal of Health Service Management
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• v.13 no.4
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• pp.109-119
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• 2019

Objectives: The purpose of this study was to find out the relationship between academic burn out and the quality of life of college students of health and medical science, and to examine the mediating effects of self-efficacy on the relationship between them. Methods: The data of 379 college students of health and medical science in the Department of Korean Medicine and Nursing located in A and D cities were collected from March to July 2018, and were analyzed using SPSS 24.0 Statistics Program. Results: There was no mediating effect of self-efficacy on the Physical Component Score(PCS), which indicates the physical health index of quality of life in relation to academic exhaustion and quality of life of university students. However, the Mental Component Score(MCS), which indicates the mental health index, had a significant effect on the parameter of self-efficacy (β = .382, p <.001). Although the β value for the school exhaustion and MCS decreased from -.382 to -.209, the effect remains significant (β=-.209, p<.001). Conclusions: It is considered that the development and the application of a self-efficacy enhancement program is necessary to improve of self-efficacy and reduce academic burn out of college students of health and medical science.

• Journal of the Korean Burn Society
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• v.23 no.2
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• pp.42-53
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• 2020

Purpose: It is important to consider both clinical factors and epidemiological factors in treating burn patients in emergency rooms. However, many emergency medical staffs happen to miss their chances of treating burns based on these considerations. This study is designed to find a better treatment for burn patients in emergency rooms along this approach. Methods: This study was conducted based on the data of the burn patients visiting the emergency room of a single general hospital from January 2015 to December 2019. The epidemiological and clinical factors were extracted out of the data, then the relationship between the prognosis and these factors were analyzed. Results: Most of burn accidents occurred at home, and were caused by hot water, soup, drinks, oil, etc. Especially, flame burns showed high hospitalization rate, surgical rate and mortality. In addition, their prognosis was poor when the affected area included facial, limb and perineal areas etc., or any inhalation burn co-existed. Also, the hospitalization rate and period increased when the treatment time was delayed or the pre-treatment was taken. There was a strong relationship between prognosis and the period of follow-up when patients were admitted during the period. Conclusion: It is difficult for medical staffs to evaluate prognosis of burns in emergency rooms due to progressive damages. Precise treatment and disposition are essential for patients' good prognosis. Therefore, medical staffs should establish treatment plans by identifying the patient's epidemiological and clinical factors, rather than giving prescriptions based on fragmentary and superficial symptoms.

• Aerospace Engineering and Technology
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• v.6 no.1
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• pp.165-172
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• 2007

A space launch vehicle is a very complex system composed of many kinds of components. It is necessary for even a small piece of components in it to be free of defects, malfunctions and to operate normally for the sake of the mission success. For these reasous, a variety of tests are carried out. Burn-in test is to detect latent material and workmanship defects which occurs early in the components use. Developed countries for the space technology have considered the burn-in test for flight vehicles in the standard test documents and performed it. Referred to the documents, application methods of burn-in test will be considered for the components of domestic space launch vehicles such as KSLV-I in this document.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.6 no.1
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• pp.18-26
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• 1997

Grinding burn formed on the ground surface is related to the maximum temperature of workpiece surface and wheel tempertaure in the grinding process. The thermal characteristics of workpiece and grinding conditions on the surface tempertaure of the oxidation growing layer after get out of contact with the grinding wheel. The assumption used in grinding power signatures leads to the local temperature distribution between grinding wheel and workpiece, i.e., a single curve determines temperatures anywhere within the grinding wheel at anytime. This information is useful in the study of the grinding burn penetration into the wheel and thus provides an presentation of grinding trouble monitoring for the burning. On the basis of grinding power signatures in the wheel, thermally optimum grinding conditions are defined and controlled. To cope with grinding burn, the use of grinding power signatures is an effective monitoring systems when occurring the grinding process. In this paper, the identified parameters suggested in this study which are derived from the grinding power signatures are presented, and prediction model by grinding power utilized a linear regression algorithm is applied.