• 한국ITS학회 논문지
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• 제16권4호
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• pp.92-106
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• 2017

기상 악화 시 운전자의 시인성이 저하되어 교통 흐름에 영향을 미치며 이는 교통 정체나 교통사고를 유발시킨다. 특히, 안개가 발생할 경우 다른 기상 요인과는 달리 교통사고가 대형 교통사고로 이어지며 치사율도 높은 것으로 알려져 있다. 본 연구에서는 교통류에 영향을 미치는 가시거리 수준을 도출하기 위해 악천후 중 안개 발생 시 교통특성을 분석하였다. 연속류 도로를 대상으로 안개 발생 시와 미 발생 시의 교통량 및 속도 변화를 비교 분석하였으며, 가시거리 수준별 교통량-속도-밀도 관계를 분석하였다. 분석 결과, 동일시간대의 교통량 변화는 거의 없는 것으로 나타났으며 속도는 가시거리가 짧을수록 감소하는 것으로 나타났다. 또한, Q-U-K 관계에서 가시거리 200m 이하의 안개 발생 시 미 발생 시와 뚜렷한 차이를 보여 교통류에 영향을 미치는 것으로 분석되었다. 본 연구 결과를 기반으로 교통류에 영향을 미치는 가시거리 수준 판단이 가능하여 향후 안개 발생 시 제한 속도 제어, 교통량 제어 등 교통 운영 전략의 공학적 기초자료로 활용될 수 있을 것으로 기대된다.

• 한국항해항만학회지
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• 제42권6호
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• pp.415-420
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• 2018

국제해사기구의 해양환경안전위원회에 의해 도입된 에너지효율설계지수는 이산화탄소 배출량 규제를 위해 필요하나, 선박의 감속운항과 주기관 출력 저하로 황천항해 시 사고로 이어질 수 있다. 이에 해양환경안전위원회는 황천항해 시 선박의 침로유지를 위한 주기관 최소출력에 대한 지침을 제시하였으나, 이는 재화중량톤수 20,000톤 이상 선박에 대한 것으로 중소형 선박에 대한 기준은 부재하다. 본 연구는 최소출력에 대한 지침을 근거로 지침 적용대상인 선박을 평가하고, 수정된 지침을 제안하였다. 또한 지침 미적용 대상인 재화중량톤수 20,000톤 미만의 중소형 선박들에 대한 주기관 최소출력 제시를 목적으로 관련 해양사고 사례들을 조사하고, 선박의 크기에 따른 주기관 출력을 분석하여 중소형 선박에 적용될 수 있는 주기관 최소출력 기준을 제시하였다. 연구의 결과는 악천후 시 중소형 선박들의 해양사고 감소를 위해 선박 건조에 고려될 수 있는 최소출력 기준으로 이용될 수 있을 것이다.

• Wind and Structures
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• 제19권2호
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• pp.185-197
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• 2014

Ventilation and fire safety design in road tunnels are one of the most complex issues that need to be carefully considered and analysed in the designing stage of any potential upgrade of ventilation and other fire safety systems in tunnels. Placement road tunnels space has an important influence on fire safety, especially when considering the effect of adverse wind conditions that significantly influence ventilation characteristics. The appropriate analysis of fire and smoke control is almost impossible without the use of modern simulation tools (e.g., CFD) due to a large number of influential parameters and consequently extensive data. The impact of the strong wind is briefly presented in this paper in the case of a longitudinally ventilated road tunnel Kastelec, which is exposed to various severe wind conditions that significantly influence its fire safety. The possibility of using CFD simulations in the analysis of the tunnel placement in space terms negative effect of wind influence on the tunnel ventilation is clearly indicated.

• 대한수의사회지
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• 제48권9호
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• pp.540-543
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• 2012

Livestock excretes are frequently used in organic farming to produce vegetables and crops. However, zoonotic parasite eggs can be contaminated into such products and people can be infected with parasites of animal origin. Sporadic zoonotic infections with Ascaris suum have been reported even in developed countries, such as North America, Denmark, and the United Kingdom. Ascaris eggs are resistant to most adverse environmental conditions, and pigs and humans become infected by ingestion of fecally excreted eggs through contaminated food, water, or soil. This article discusses the resistant nature of ascarid eggs against harsh environment, and conditions of kimchi to be safe from consuming viable A. suum eggs.

• Journal of Microbiology
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• 제43권5호
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• pp.443-450
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• 2005

The multi-host pathogen, Pseudomonas aeruginosa, possesses an extraordinary versatility which makes it capable of surviving the adverse conditions provided by environmental, host, and, presumably, competing microbial factors in its natural habitats. Here, we investigated the P. aeruginosa-Bacillus subtilis interaction in laboratory conditions and found that some P. aeruginosa strains can outcompete B. subtilis in mixed planktonic cultures. This is accompanied by the loss of B. subtilis viability. The bactericidal activity of P. aeruginosa is measured on B. subtilis plate cultures. The bactericidal activity is attenuated in pqsA, mvfR, lasR, pilB, gacA, dsbA, rpoS, and phnAB mutants. These results suggest that P. aeruginosa utilizes a subset of conserved virulence pathways in order to survive the conditions provided by its bacterial neighbors.

• 대한음성학회:학술대회논문집
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• 대한음성학회 2006년도 춘계 학술대회 발표논문집
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• pp.45-48
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• 2006

As the speech recognition systems are used in many emerging applications, robust performance of speech recognition systems under extremely noisy conditions become more important. The voice activity detection (VAD) has been taken into account as one of the important factors for robust speech recognition. In this paper, we investigate conventional VAD algorithms and analyze the weak and the strong points of each algorithm.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1996년도 춘계학술발표회논문집(4)
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• pp.321-326
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• 1996

During the plant operation, steam generator U-tube assembly will potentially be subject to adverse environmental conditions which can cause damages to them. This report addresses the major design factors of CANDU type steam generator which are intended to minimize the potential tube damages. Such factors include U-tube material, high circulation ratio, tube-to-tubesheet joint, tube support design. Also a few suggestions are presented for the design and performance improvement of CANDU type steam generators.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.144.2-145
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• 2003

Reactive Oxygen Species (ROS) are produced during normal cellular function. ROS are very transient species due to their high chemical reactivity that leads to lipid peroxidation and oxidation of some enzyme, massive protein oxidation and degradation. Under normal conditions, antioxidant are substances that either directly or indirectly protect cells against adverse effects of ROS. Several biologically important compounds have been reported to have antioxidant functions. These incluce vitamin C, vitamin E, GSH, flavonoids. superoxidee dismutase(SOD), glutathione peroxidase(GPX) and catalase(CAT). (omitted)

• Toxicological Research
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• 제20권3호
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• pp.273-280
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• 2004

The present study was carried out to investigate the potential toxicity of dimethyl disulfide by a 2-week inhalation in F344 rats. The test article, dimethyl disulfide, was exposed by inhalation to male and female rats at dose levels of 0, 33, 100, or 300 ppm/6 hrs/day for 2 weeks. At the end of treatment period, all males and females were sacrificed. During the test period, clinical signs, mortality, body weights, food consumption, hematology, serum biochemistry, and gross findings were examined. The mean body weights of the male 300 ppm group and the female 33 ppm or higher dose groups were significantly lower than those of the control group, respectively. The mean food consumption at male 300 ppm and female 100 and 300 ppm were significantly decreased compared with the controls. Some treatment-related serum biochemical changes, including decreased alkaline phosphatase at male 300 ppm and female 100 and 300 ppm, reduced total bilirubin at male 300 ppm, and decreased alanine aminotransferase at female 300 ppm, were observed in a dose-dependent manner, but these findings were considered to be of no toxicological significance. There were no adverse effects on mortality, clinical signs, hematology, and necropsy findings in any treatment group. Based on these results, it was concluded that the 2-week repeated dose of dimethyl disulfide by inhalation resulted in suppressed body weight gain and decreased food consumption at the dose of male 300 ppm and suppressed or reduced body weight gain and decreased food consumption at the dose of female 33 ppm or higher. In the present experimental conditions, the no-observed-adverse-effect level (NOAEL) was considered to be 100 ppm/6 hrs/day for male rats and below 33 ppm/6 hrs/day for female rats.

• 대한한의학회지
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• 제28권1호통권69호
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• pp.1-10
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• 2007

Background : There has been renewed interest in complementary alternative medicine around the world far a decade. On the other hand, the issue of safety of herbal medicine in Korea has been continuously questioned. Issues raised have included not only chemical residue or heavy metals caused by pollution, but also the toxicity of herbal medicine itself. Objectives : The purpose of this study was to review some herbal medicines subject to controversy of toxicity and figure out what kind of problems they evidence. Methods : In this review, PubMed was used to search medical journals. Keywords such as 'herb, or herbal medicine', 'safety, or adverse events, or adverse effect, or toxicity, or liver injury' were applied. Journals were selected by four inclusion criteria, as objectives should be human, researchers should be medical doctors, literature written in the English language, and types of journals should be meta-analysis or practice guideline or reviews. Finally, 9 cases from 60 journals were included in this review. Results : We reviewed 13 herbal medicines for controversy of toxicity such as ephedra(Mahuang), Arisolochia fangchi, Aristolochia manshuriensis, licorice, skullcap , germander, Syo-saiko-to(Xiao-chai-hu-tang), Chelidonium majus, mistletoe, Dictamnus dasycarpus and madder. Conclusions : It suggested that 'who it is prescribed for' is one of the most important factors to identify the causes of toxicity in herbal medicine and dietary supplements, under specific conditions in Korea.