• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2005년도 제24회 춘계학술대회논문집
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• pp.23-26
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• 2005

LOx와 Kerosene을 연료로 사용하는 LRE(Liquid Rocket Engine) Block에서 지상연소시험을 수행할 경우에 발생하는 위험도를 감소시키는 방법을 연구하였다. 추진제누출로 이어지는 위험한 상황에 대한 원인분석도와 추진제 유출시 사고로 이어지는 발전 양상 및 발전 프로세스, 사고시 손실을 줄이기 위한 기술적인 해결방법을 제시함으로써 기존의 확률적인 통계 값을 바탕으로 하는 것과는 또 다른 방법으로써 위험을 감소하기 위한 대안으로 사용하고자 한다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제46권2호
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• pp.87-98
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• 2020

The aim of this study was to determine the efficacy of oral splints in reducing the intensity of pain in patients with temporomandibular joint dysfunction in both short and long-term treatment durations. Electronic databases, Cochrane Library, MEDLINE via PubMed, Web of Science, Egyptian Knowledge Bank, and EMBASE were searched for randomized controlled trials comparing different types of splints to non-occluding splints, behavioral therapy, pharmacotherapy, counseling, and no treatment. The risk of bias was assessed by using Cochrane risk of bias recommendations. Fixed and random effects were used to summarize the outcomes. The effect estimates were expressed as standardized mean differences (SMD) or risk ratios with a 95% confidence interval (CI). Subgroup analyses were carried out according to the treatment duration. Twenty-two studies met the inclusion criteria. A meta-analysis of short-term studies up to three months revealed no significant difference between the study groups. However, long-term studies exhibited a significant difference in pain reduction in favor of the control group. Total analysis revealed that the control group resulted in significant pain reduction (SMD 0.14, 95% CI 0.05-0.23, P=0.002, I²=0%). Oral splints are not effective in reducing pain intensity or improving function in patients with temporomandibular joint dysfunction.

• Restorative Dentistry and Endodontics
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• 제46권2호
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• pp.19.1-19.12
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• 2021

Objectives: The purpose of this study was to conduct a systematic review and meta-analysis of in vitro studies regarding the effectiveness of reciprocating and rotary instrumentation on microbial reduction in root canals. Materials and Methods: PubMed, Scopus, Web of Science, the Cochrane Library, and the gray literature were searched through December 2019. Studies comparing the influence of reciprocating and rotary instrumentation on the removal of microorganisms from root canals that quantified the antimicrobial effect were included. Data extraction was completed using a systematic form for data collection. The risk of bias of the studies was evaluated. Standardized mean differences (SMDs) and confidence intervals (CIs) were calculated using a random effects meta-analysis. Results: Seventeen in vitro studies were included in this systematic review, of which 7 provided adequate data for inclusion in the meta-analysis. Both reciprocating and rotary systems were similarly effective in reducing the microbial load in infected root canals (SMD [95% CI], 0.0481 [-0.271, 0.367]). Three studies showed a low risk of bias, whereas most of the studies (82%) presented a medium risk. Conclusions: Although both techniques decrease the microbial content (with reductions of 23.32%-88.47% and 23.33%-89.86% for reciprocating and rotary instrumentation, respectively), they are not able to provide complete disinfection of root canals.

• 건축역사연구
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• 제29권3호
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• pp.7-14
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• 2020

It can be meaningful that this study attempted to analyze the use cases and forms based on the literature on the painting walls of the J oseon Dynasty, and attempted basic research to prevent disaster damage using traditional elements. This study summarizes the use of the Hwabangbyeok wall of J oseon Dynasty as follows. First, Hwabangbyeok wall was used from the early J oseon Dynasty and was adopted by palaces and other major state facilities to cope with fire and theft. Second, the Hwabangbyeok Wall was also referred to as the wall below the lower part of the wall, and was constructed with the purpose of preventing disasters from outside. Third, in an analysis of the Daeseongjeon shrine of Hyanggyo, many construction cases were identified mainly in the Gyeonggi area, which is assumed to be based on production and construction conditions along with local climatic factors. Fourth, it can be said that the Hwabangbyeok wall was basically adopted to prevent comprehensive disaster risk reduction in case of external intrusion and fire.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제32권1호
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• pp.43-48
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• 2010

The mandibular condyle fracture occurs at 15-30% frequency of whole mandibular fracture. The treatment of choice is open reduction or closed reduction. In many cases, closed reduction is preferred for treatment of condylar fracture because it is hard to approach to condyle and there is risk of surgical complications, such as nerve damage in open reduction. Open reduction, however, has some advantages like possibility of anatomical reduction, occlusal stability and rapid functional recovery. Furthermore, it is possible to retain original ramal heights and to decrease deviation during mouth opening. There are many surgical approaches for open reduction of subcondyle fracture. At present, transoral approach using trochar device is tried for effective and minimally invasive method for open reduction of subcondyle fracture. And the authors report the cases of reduction of subcondyle fracture with transoral approach using trochar device.

• Asian Pacific Journal of Cancer Prevention
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• 제13권11호
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• pp.5327-5332
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• 2012

In this review, we describe the patterns of known immunological components in breast milk and examine the relationship between breastfeeding and reduced risk of breast cancer. The top risk factors for breast cancer are a woman's age and family history, specifically having a first-degree relative with breast cancer. Women that have a history of breastfeeding have been shown to have reduced rates of breast cancer. Although the specific cause has not been elucidated, previous studies have suggested that breastfeeding reduces the risk of breast cancer primarily through two mechanisms: the differentiation of breast tissue and reduction in the lifetime number of ovulatory cycles. In this context, one of the primary components of human milk that is postulated to affect cancer risk is alpha-lactalbumin. Tumour cell death can be induced by HAMLET (a human milk complex of alpha-lactalbumin and oleic acid). HAMLET induces apoptosis only in tumour cells, while normal differentiated cells are resistant to its effects. Therefore, HAMLET may provide safe and effective protection against the development of breast cancer. Mothers should be encouraged to breastfeed their babies because the complex components of human milk secretion make it an ideal food source for babies and clinical evidence has shown that there is a lower risk of breast cancer in women who breastfed their babies.

• 한국건설관리학회논문집
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• 제6권5호
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• pp.119-127
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• 2005

최근의 건설시장 축소와 주 5일 근무제도, 공기단축형 입찰제도의 도입, 후분양제도의 도입 등의 제도적 변화에 따라 건설 수주 경쟁은 더욱 치열해지고 있다. 그러나 건설공사는 공기지 연을 유발하는 수많은 공정리스크가 존재하고 있으며 이러한 공정리스크에 대한 인식과 그에 따른 체계적인 관리가 부진한 경우 건설공사의 경쟁력을 확보하는 데 여러 어려움이 존재한다. 이러한 문제점을 해결하기 위한 기존 연구는 공정리스크의 분류, 공정 리스크의 관리, 리스크 관리를 위한 시스템 개발에 치중하였다. 이에 본 연구는 전체 공정에 영향력이 크며, 위험발생 확률이 높은 철근콘크리트공사를 대상공종으로 선정하고 기존연구를 바탕으로 수차례의 전문가 면담과 난상토론을 실시하여 현실적인 리스크 요인과 관리방안을 제시하였다.

• 한국가스학회지
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• 제13권3호
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• pp.22-27
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• 2009

이 논문은 한국가스안전공사가 도시가스 고압배관에 대한 안전성평가를 실시하고 안전관리 조치를 권고하는 경우 그 안전관리조치가 합리적으로 실행가능한 것인지를 판단하기 위한 비용.편익분석 방법으로 PF(Proportion Factor)를 사용할 것을 제시하였다. 또한, 설치 예정인 도시가스 고압배관에 대하여 정량적 위험성평가를 실시하고, 평가결과에 따라 개선 권고한 안전조치에 대하여 VPF와 PF를 이용한 비용 편익분석을 실시하여 제시한 위험감소조치가 합리적으로 실행가능한 것임을 확인할 수 있었다. 본 논문에서 제시한 비용 편익분석방법은 국내에서 안전성평가를 실시하고 위험감소조치를 제시하는 경우 그 조치가 합리적으로 실행 가능한 것인지를 입증하는데 유용하게 활용될 수 있을 것으로 판단된다.

• 대한안전경영과학회지
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• 제16권2호
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• pp.31-42
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• 2014

As weapon systems become complex in terms of the scale and functionality, the required time to complete the test and evaluation (T&E) process is inevitably getting longer. However, nowadays the reduction of T&E period becomes one of the core targets in the weapon systems acquisition programs. This is because the reduced time for T&E process can yield the reduction of defense budget and also faster deployment of the weapon systems, thereby having a competitive edge over rival countries. On the other hand, in weapon systems development the management of reliability, availability, maintainability and safety (RAMS), and risk is considered important to keep competitiveness and thus has been carried out separately. Thus, the objective of this paper is to study on improving the T&E process by integrating the RAMS and risk management process in it. To do so, the related processes are analyzed and modeled first. Then an integrated process model is developed. The resulting model is equipped with the traceability among the data and interfaces that are generated from the T&E and RAMS/risk processes. As a case study, the model developed is applied in tanks development. The effective use of the traceability is expected to reduce the time and cost required to complete T&E process.

• 대한영양사협회학술지
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• 제23권4호
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• pp.408-430
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• 2017

The purpose of this study was performed to investigate dietary and lifestyle habits, dietary behaviors, and food frequency according to the level of smartphone addiction among 408 university students in Kyungnam province. Statistical analyses were performed using the SPSS software package. Based on using the Smartphone Addiction Poneness Scale, 28.4% were potential-risk smartphone users and while 13.2% were high-risk smartphone users. The levels of depression (P<0.05) and stress (P<0.05) and frequency of snacks (P<0.01) were higher in high-risk and potential-risk groups than in the normal group, and meal frequency was highest in the high-risk group (P<0.01). Percentages of using a smartphone at meal time (P<0.01) and snacking while using a smartphone (P<0.01) were higher in potential-risk and high-risk groups than in the normal group. Percentages of skipping meals (P<0.001) and slow eating speed (P<0.01) due to using a smartphone were higher in high-risk and potential-risk groups than in the normal group, and percentages of taste change (P<0.05) were higher in the high-risk group than in the potential-risk and normal groups. Percentages of exercise reduction (P<0.01), body weight increase (P<0.05), sleep disturbance (P<0.001), and increase in stress (P<0.01) due to using a smartphone were higher in the high-risk group than in the normal group. Scores of dietary behaviors avoiding salty food (P<0.01) and excessive drinking (P<0.001) were higher in the high-risk group than in the normal group. Scores for frequency of oil or nuts (P<0.05) and fatty meats (P<0.01) were highest in the high-risk group. Our results suggest that effective nutrition education programs are needed to solve unhealthy dietary and lifestyle habits from high-risk smartphone users in university students.