• 환경생물
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• 제29권4호
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• pp.241-250
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• 2011

현대인들은 가정생활과 직업환경 속에서 다양한 종류의 전자기파에 노출되며 전자기파 노출에 따른 생체위해성은 공중보건학적으로 중요한 이슈로 대두되었다. 현재까지 많은 체외 및 체내실험 결과에서 전자기파 노출이 세포대사, 내분비, 면역, 신경, 생식, 태아발달에 영향을 미치는 것으로 보고되었다. 세포나 개체 수준에서 시행된 실험연구에서는 전자기파 노출에 의해 세포내부 자유기의 증가, DNA 손상과 암발생, 발생기형, 생식기능 저하가 나타난다. 역학조사결과 전자기파 노출은 생명을 위협하는 질병인 백혈병, 뇌암, 근위축성 측삭경화증, 우울증, 자살, 알츠하이머와 상관성이 보고되었다. 이러한 생체기능 변화는 전자기파의 주파수, 노출기간, 강도 (에너지)에 따라 다르게 나타난다. 전자기파 노출은 곤충, 어류, 양서류, 파충류, 조류 등 야생동물에서도 동물행동, 번식, 생리기능의 변화를 초래한다. 본 소고에서는 인간보건학적 측면과 생태계에서 나타난 전자기파의 위해성을 전자기파의 종류, 노출시간에 따라 세포 및 개체 수준에서 보고된 위해성 자료를 정리하였다.

• Asian Pacific Journal of Cancer Prevention
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• 제16권13호
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• pp.5573-5578
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• 2015

Background: A systematic review and meta-analysis were performed to compare the post-recurrence survival with hepatic re-resection versus transarterial chemoembolization (TACE) for recurrent hepatocellular carcinoma (HCC) after initial resection. Materials and Methods: All relevant papers were searched via PubMed, EMBASE, and Cochrane Library databases. Hazard ratios (HRs) with 95% confidence intervals (CIs) were pooled using a random-effects model. Subgroup analysis was performed according to country. Sensitivity analysis was performed in studies which clearly reported the recurrent regions, in moderate/high-quality studies, in studies published in full-text form, and in studies published after 2005. Results: In total, twelve papers were included in our study. Five and seven of them were of moderate- and poor-quality, respectively. The overall meta-analysis demonstrated a statistically significantly higher post-recurrence survival in the hepatic re-resection group than in those undergoing TACE (HR=0.64, 95%CI=0.52-0.79, P<0.0001). Heterogeneity was statistically significant and statistical significance remained in the subgroup analysis. Sensitivity analyses were also consistent with the overall analysis. Conclusions: Hepatic re-resection might provide a better post-recurrence survival than TACE for recurrent HCC after initial resection. However, considering the low quality of published studies and the potential bias of treatment selection, further randomized trials should be warranted to confirm these findings.

• 척추신경추나의학회지
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• 제17권2호
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• pp.131-139
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• 2022

Objectives This study aimed to analyze the medical utilization of low back pain (LBP) patients after back surgery and estimate the medical costs of Korean and Western medicine collaborative treatment, odds ratio, and hazard ratio between the two groups using the 2019 Health Insurance Review and Assessment Service-National Patient Sample (HIRA-NPS-2019). Methods Data management and descriptive analysis, logistic regression, and survival analysis were conducted for defining and estimating the LBP patients after back surgery in the NPS 2019 dataset. Results A total of 216,424 patients out of 991,189 were identified as having LBP. Among the patients with LBP, 1,734 were treated with surgery while 214,690 were not. Among those who had surgery, 937 were treated with conventional treatments only and 797 underwent Korean medicine treatments. The odds ratio of the logistic regression analysis was 0.7129, suggesting that Korean medical treatment experience group had a 28.7% lower risk of reoperation than the Western medical treatments only group. The hazard ratio of the survival analysis was 0.9145; thus, the risk probability of reoperation was estimated to be approximately 8.55% lower. The 50% risk of reoperation was 69 days (0.5044) for the conventional group, and 97 days (0.5008) for the Korean medical group in the survival analysis using the Kaplan-Meier graph. Conclusions These results could be utilized in future studies in conducting economic evaluation for estimating cost-effectiveness of Western medicine and Korean medicine treatment compared to Western medicine alone in LBP patients after back surgery in a South Korean perspective. mended and should be applied while taking the necessary precautions.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제10권S_1호
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• pp.23-28
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• 2001

A new numerical weather prediction and dispersion model, the Operational Multi-scale Environment model with Grid Adaptivity(OMEGA) including an embedded Atmospheric Dispersion Model(ADM), is introduced as a next generation atmospheric simulation system for real-time hazard predictions, such as severe weather or the transport of hazardous release. OMEGA is based on an unstructured grid that can facilitate a continuously varying horizontal grid resolution ranging from 100 km down to 1 km and a vertical resolution from 20 -30 meters in the boundary layer to 1 km in the free atmosphere. OMEGA is also naturally scale spanning and time. In particular, the unstructured grid cells in the horizontal dimension can increase the local resolution to better capture the topography or important physical features of the atmospheric circulation and cloud dynamics. This means the OMEGA can readily adapt its grid to a stationary surface, terrain features, or dynamic features in an evolving weather pattern. While adaptive numerical techniques have yet to be extensively applied in atmospheric models, the OMEGA model is the first to exploit the adaptive nature of an unstructured gridding technique for atmospheric simulation and real-time hazard prediction. The purpose of this paper is to provide a detailed description of the OMEGA model, the OMEGA system, and a detailed comparison of OMEGA forecast results with observed data.

• 한국화재소방학회논문지
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• 제32권5호
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• pp.22-33
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• 2018

화재에 대한 우수한 소화력, 적응성 및 잔류물이 남지 않는 등의 장점으로 최근 할로겐화합물청정소화약제의 사용량이 증가하고 있다. 하지만 유해성에 대한 검증과 안전기준이 설정되지 않은 상태로 사용되어 사망사고 등의 재해가 다발하고 있는 실정이다. 본 논문은 문헌 및 실험연구를 통해 할로겐화합물청정소화약제의 안전한 사용을 위한 법적인 노출기준과 가스 모니터링과 연계된 정량적 환기시스템, 유해성 주지 및 적정 보호구 선정을 포함한 안전기준 설정을 제안하고자 하였다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 춘계학술대회 논문집
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• pp.188-193
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• 2008

According to introduce KTX in Korea, rail-road bridge section of KTX was increased approximately 50% of the total length. Bridge is required periodic inspection and check to prevent accident and hazard because various damage which have effects on traffic and replacement of damaged parts is difficult. Specifically, the train as large-scale transportation because accidents led to great damage, preventing these accidents are critical. Well-organized management and maintenance systems are required to prevent the accidents. In the case of roadway bridge, bridge inspection vehicle is used to deploy inspectors in roadway bridge. However, this method requires a lot of time and efforts, and inspectors are exposed to potential hazard. Also, surrounding environment like poor lighting system or electric wire could harm the inspector while repairing. Due to this reason, automatic repairing and inspecting system have been introduced to replace the old methods. Management system of the railroad bridge track for trains uses various advanced equipments, but whereas roadway bridge management system is lacking these efforts. As a result of that, this study looks over the existing management method. and review the method to apply the Bridge Inspection Robot in railroad bridge. Moreover, this study suggests future management technology using inspection robot.

• East Asian Economic Review
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• 제21권1호
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• pp.3-27
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• 2017

This paper studied the effects of anti-dumping measures on the imports to investigate whether the trade restriction effect of an anti-dumping duty is dominant. Our results indicate that a 1% increase in the anti-dumping duties decreases the import of the targeted product by about 0.43~0.51%. The actual statistics, however, show that the total import of the targeted products increased by about 30 percent while an anti-dumping duty was in force. That indicates that an anti-dumping duty is just a temporary import relief. This paper also investigated whether an anti-dumping duty is terminated in the case that the injury would not be likely to continue or recur if the duty were removed. The hazards model estimates show that increase in market share, MFN tariff rate, and dumping margin decrease the hazard of termination of an anti-dumping duty, but the increase in value added increases the hazard of termination. Generally speaking, this result indicates that the WTO member countries have regulated the overuse of an anti-dumping measure. The findings of this paper show that there is a country- and industry-wise heterogeneous characteristic in the effect as well as termination of an anti-dumping duty.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2012년도 제38회 춘계학술대회논문집
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• pp.551-554
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• 2012

한국항공우주연구원에서는 현재 1.5톤급 위성 발사체인 한국형 발사체 KSLV-II를 개발중이며 시스템의 설계 리뷰를 앞두고 있다. 또한, 발사체의 개발과정에 있어서 임무 보증 업무의 일환으로 신뢰성과 안전, 품질등을 관리하고 있으며 발사체의 안전 확보를 위해서 기존에 공표된 안전 보장 계획 및 시스템 안전 프로그램 계획에 따라 관련 업무를 수행하고 있다. 본 연구에서는 상기의 계획에 의거하여 수행된 사전 안전 분석의 내용과 방법에 대하여 설명하고 실제 추진기관 시스템에 대하여 도출된 위험요소들을 소개하고자 한다. 도출된 위험 요소들은 향후 개발이 진행되면서 위험 수준을 완화하는 방향으로 관리될 계획이다.

• 지구물리
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• 제9권3호
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• pp.199-207
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• 2006

Fukuoka earthquake on March 20, 2005 showed the potential hazard of large events out of S. Korea. From the viewpoint of seismic hazard, seismic amplitude decrease Q-1 is very important. Related to the crustal cracks induced by the earthquakes, the value of Q-1- high Q-1 regions are more attenuating than low Q-1 regions - shows a correlation with seismic activity; relatively higher values of Q-1 have been observed in seismically active areas than in stable areas. For the southeastern and central S. Korea, we first simultaneously estimated QP-1 and QS-1 by applying the extended coda-normalization method to KIGAM and KNUE network data. Estimated QP-1 and QS-1 values are 0.009 f-1.05 and 0.004 f-0.70 for southeastern S. Korea and 0.003 f -0.54 and 0.003 f -0.42 for central S. Korea, respectively. These values agree with those of seismically inactive regions such as shield. The low QLg-1 value, 0.0018f -0.54 was also obtained by the coda normalization method. In addition, we studied QLg-1 by applying the source pair/receiver pair (SPRP) method to both domestic and far-regional events. The obtained QLg-1 for all Fc is less than 0.002, which is reasonable value for a seismically inactive region.

• KEPCO Journal on Electric Power and Energy
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• 제8권2호
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• pp.79-86
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• 2022

Recently, the amount of maintenance is increasing due to the aging of power facilities, but the budget is constrained. Therefore, the importance of asset management that selects replacement priorities based on the failure probability and enhances investment effects is increasing. Because the number of distribution transformers is very large, the proportion of investment cost is very high. Therefore, it is important to select the investment priority by evaluating the reliable remaining life based on the failure probability. This paper evaluates the statistical expected life using the failure data of distribution transformers for the last 11 years and the current operation data. The hazard rate of distribution transformer and MV cable was compared with each other and the adequacy of early failure removal was reviewed and the statistical expected life corresponding to the cumulative failure probability B3% was calculated.