• 자연, 터널 그리고 지하공간
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• 제20권3호
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• pp.10-20
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• 2018

• 자연, 터널 그리고 지하공간
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• 제22권2호
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• pp.9-37
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• 2020

• 자연, 터널 그리고 지하공간
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• 제20권4호
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• pp.9-24
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• 2018

• 자연, 터널 그리고 지하공간
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• 제21권1호
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• pp.6-17
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• 2019

• 자연, 터널 그리고 지하공간
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• 제21권3호
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• pp.9-25
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• 2019

• 한국터널지하공간학회 논문집
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• 제6권4호
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• pp.357-365
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• 2004

Tunnel portals are often located in areas where the risk of rock fall and/or detachement of rock fragments from rocky slopes is high. In this case it is necessary to design the portals so as to protect the road (i.e. using an artificial tunnel) or to instal structures that are able to intercept falling blocks on the slope. This paper deals with the design problems of these structures and includes a special analysis of net fences which have undergone a remarkable technological improvement over recent years.

• 대한안전경영과학회지
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• 제18권3호
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• pp.47-54
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• 2016

A confined space means places where the risk of damage to health caused by lack of oxygen or hazardous gases in inadequate ventilation conditions and the risk of fire and explosion caused by flammable substances. Asphyxiation accidents in a confined space occured every year and also occurred more than two people at the same time. In this study, we surveyed the domestic statistical data occurred the lack of oxygen in confined space for the last 10 years(2006-2015) and, analyzed the accident by industries sector, workplace size etc. 17 fatal work accidents that occurred in confined spaces in Korea between 2013 and 2015 were investigated and analyzed using the database of the KOSHA and suggested interventions to minimize asphyxiation accidents in confined spaces. This paper is expected to be used to establish interventions planning and training as a preventive measures in workplace having confined spaces.

• Asian Pacific Journal of Cancer Prevention
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• 제16권13호
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• pp.5331-5335
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• 2015

Purpose: The aim of this study was to compare the tumor-free and overall survival rates between patients with low-risk endometrial cancer who underwent surgical staging and those who did not undergo surgical staging. Materials and Methods: Data, including demographic characteristics, grade of the tumor, myometrial invasion, cervical involvement, peritoneal washing, lymph node involvement, lymphovascular space invasion, postoperative complication, adjuvant treatment, cancer recurrence, and tumor-free and overall survival rates, for patients with low-risk endometrioid endometrial cancer who were treated surgically with and without pelvic and paraaortic lymph node dissection (LND) were analyzed retrospectively. The patients diagnosed with endometrioid endometrial cancer including the following criteria were considered low-risk: 1) a grade 1 (G1) or grade 2 (G2) endometrioid histology; 2) myometrial invasion of <50% upon magnetic resonance imaging (MRI); 3) no stromal glandular or stromal invasion upon MRI; and 4) no evidence of intra-abdominal metastasis. Then the patients at low-risk were divided into two groups; group 1 (n=117): patients treated surgically with pelvic and paraaortic LND and group 2 (n=170): patients treated surgically without pelvic and paraaortic LND. Results: There was no statistical significance when the groups were compared in terms of lymphovascular space invasion, cervical involvement, positive cytology, and recurrence, whereas the administration of an adjuvant therapy was higher in group 2 (p<0.005). The number of patients with positive pelvic nodes and the number of metastatic pelvic nodes were significantly higher in the group with positive LVI than in the group without LVI (p<0.005). No statistically significant differences were detected between the groups in terms of tumor-free survival (p=0.981) and overall survival (p=0.166). Conclusions: Total hysterectomy with bilateral salpingo-oophorectomy and stage-adapted postoperative adjuvant therapy without pelvic and/or paraaortic lymphadenectomy may be safe and efficient treatments for low-risk endometrial cancer.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제36권5호
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• pp.185-191
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• 2014

Purpose: Although there have been several studies of reduced airway space after mandibular setback surgery using the sagittal split ramus osteotomy technique, research on the risk factors for changes of the airway space is lacking. Therefore, this study was performed to examine airway changes and the position of the hyoid bone after orthognathic surgery, and to assess possible risk factors. Methods: In this retrospective study, 50 patients who underwent posterior displacement of the mandible by the bilateral sagittal split ramus osteotomy technique were included. Changes of the position of the hyoid bone and the airway space were analyzed over various follow-up periods, using cephalometric radiography taken preoperatively, immediately after surgery, eight weeks after surgery, six months after surgery, and one year after surgery. To identify risk factors, multiple regression analysis of age, gender, body mass index (BMI), posterior mandibular movement, and the presence of genioplasty was performed. Results: Inferor and posterior movement of the hyoid bone was observed postoperatively, but subsequent observations showed regression towards the anterosuperior aspect. The airway space also significantly decreased after surgery (P<0.05), and increased slightly up until six months after surgery. The airway space significantly decreased (${\beta}=0.47$, P<0.01) as the amount of mandibular setback increased. However, age, sex, BMI, and presence of genioplasty were not associated with airway reduction. Conclusion: The amount of mandibular set back was significantly associated with postoperative reduction of airway space. It is necessary to establish a treatment plan considering this factor.

• 한국항공우주학회지
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• 제42권2호
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• pp.158-164
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• 2014

IADC의 '25년 규정'에 의해 미션종료 된 저궤도 인공위성은 25년 이내에 지구로 재진입, 소각 폐기되도록 권고하고 있다. 이때 인공위성의 부품일부 또는 다수가 살아남아 지상에 충돌할 경우 인명 및 재산피해를 낼 수 있다. 우리나라의 경우 저궤도 위성으로서 아리랑 인공위성과 과학기술위성을 운용 중에 있으며 임무종료 후에는 모두 대기권 재진입을 통한 폐기처리가 필수이다. 따라서 본 논문에서는 ESA의 DRAMA내부의 SARA(Re-entry Survival and Risk Analysis)모듈을 이용하여 지상피해가 예측되는 크기인 가상위성의 추락궤적 및 생존부품을 분석하고 그에 따른 지상충돌확률, 피해확률을 분석하였다. 분석결과 198.831kg이 생존할 것으로 예상되며 추락지점이 한반도일 경우 전체 피해면적은 $15.2742m^2$, 피해확률은 5.9614E-03(2D)일 것으로 예상된다.