• Journal of the Korean Data and Information Science Society
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• 제17권3호
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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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• 제50권1호
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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.

• 한국산학기술학회논문지
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• 제21권5호
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• pp.433-442
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• 2020

본 연구는 소방공무원들의 직무스트레스와 소진 정도와의 관련성을 규명하고자 실시하였다. 연구대상은 D광역시 5개구의 5개 소방서에서 근무하고 있는 소방공무원 582명으로 하였으며, 조사는 2019년 7월 1일부터 9월 30일까지의 기간 동안에 구조화된 무기명 자기기입식 설문지를 이용한 설문조사에 의하였다. 연구결과, 조사대상자의 소진 정도는 직무스트레스 총점이 낮은 군보다 높은 군일수록 유의하게 높았으며, 소진과 직무스트레스와의 상관관계에서도 유의한 양의 상관관계를 보여 직무스트레스가 높을수록 소진정도가 심해지는 것으로 나타났다. 소진에 대한 직무스트레스의 관련성을 알아보기 위하여 로지스틱회귀분석을 실시한 결과, 「고위험 소진 군」이 나타날 위험비는 직무스트레스가 낮은 군에 비해 매우 높은 군에서 유의하게 높았다. 소진에 영향을 미치는 요인을 알아보기 위해 다중회귀분석을 실시한 결과, 소진에 영향을 미치는 요인으로는 성, 연령, 근무경력, 교대근무여부, 업무의 신체적 부담정도, 업무에 대한 만족도, 직업전환의사 및 직무스트레스가 유의한 변수로 선정되었다. 이상과 같은 연구결과는 소방공무원들의 직무스트레스는 소진 정도와 밀접한 관련성이 있음을 시사하고 있어 직무스트레스 요인을 적절하게 통제할 수 있는 프로그램의 개발 및 운영이 필요하다고 본다.

• Archives of Plastic Surgery
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• 제32권4호
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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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• 제32권4호
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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.

• 보건의료산업학회지
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• 제13권4호
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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.

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2003년도 추계총회 및 연구발표회 초록집
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• pp.165.1-165
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• 2003

• 대한화상학회지
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• 제23권2호
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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.

• 항공우주기술
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• 제6권1호
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• pp.165-172
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• 2007

우주 발사체는 수많은 부품으로 이루어져 있기 때문에 개발 성공을 위해서는 사소한 부품 하나라도 그 기능을 제대로 발휘하고 고장이 없어야 한다. 이를 위해서 우주 발사체용 부품 및 시스템 개발에는 수많은 시험을 수행하게 된다. 일반적으로 번인시험(burn-in test)은 생산된 제품이 재질이나 작업자의 미숙에 의해 초기 사용기간 중 발생될 수 있는 고장요인을 찾아내기 위한 시험을 통칭한다. 해외 선진국의 경우 번인시험에 대해 규격으로 기술하고 있으며 이에 따라 시험을 수행한다. 본 논문에서는 KSLV-I과 같이 국내에서 개발될 우주 발사체용 부품에 대한 번인시험 적용방법에 대해 고려해 보고자 한다.

• 한국생산제조학회지
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• 제6권1호
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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.