• 한국해양학회지:바다
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• 제21권4호
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• pp.125-133
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• 2016

본 연구는 통영연안의 오염 현황을 파악하기 위하여 표층퇴적물의 유기물 분포 특성, 미량금속의 공간적인 분포 특성과 오염도 및 생태계 위해성평가를 하였다. 총질소(Total nitrogen, TN), 총유기탄소(Total organic carbon, TOC)와 산 휘발성 황화물(Acid volatile sulfide, AVS)은 협수로에 위치한 정점 35-38에서 높은 농도를 나타내었다. Cd, Cr, Ni, Co, Hg, Zn의 공간적 분포양상은 유사하였으며, 이와 달리 Cu는 협수로에서 높은 농도를 나타내었다. 미량금속 원소의 오염도를 농축계수(Enrichment Factor, EF)로 평가한 결과, Cd이 모든 정점에서 오염되지 않은 상태(No enrichment), Pb, Cr, Ni, Co, Zn, Hg이 약간 오염상태(Minor enrichment), Cu가 약간~중간 오염상태(minor-moderate enrichment)의 오염도를 나타냈다. 미량금속에 의한 생태위해성 수준은 오비도와 미륵도 사이의 협수로 정점에서 국지적으로 생태계에 잠재적 위해성이 있는 것으로 나타났다.

• Geomechanics and Engineering
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• 제27권6호
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• pp.605-614
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• 2021

Water inrush from fault is one of the most severe hazards during tunnel excavation. However, the traditional evaluation methods are deficient in both quantitative evaluation and uncertainty handling. In this paper, a comprehensive methodology method combined intuitionistic fuzzy AHP with a Bayesian network for the risk assessment of water inrush from fault in the subsea tunnel was proposed. Through the intuitionistic fuzzy analytic hierarchy process to replace the traditional expert scoring method to determine the prior probability of the node in the Bayesian network. After the field data is normalized, it is classified according to the data range. Then, using obtained results into the Bayesian network, conduct a risk assessment with field data which have processed of water inrush disaster on the tunnel. Simultaneously, a sensitivity analysis technique was utilized to investigate each factor's contribution rate to determine the most critical factor affecting tunnel water inrush risk. Taking Qingdao Kiaochow Bay Tunnel as an example, by predictive analysis of fifteen fault zones, thirteen of them are consistent with the actual situation which shows that the IFAHP-Bayesian Network method is feasible and applicable. Through sensitivity analysis, it is shown that the Fissure development and Apparent resistivity are more critical comparing than other factor especially the Permeability coefficient and Fault dip. The method can provide planners and engineers with adequate decision-making support, which is vital to prevent and control tunnel water inrush.

• Toxicological Research
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• 제28권2호
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• pp.129-137
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• 2012

Probabilistic ecological risk assessment (PERA) for deriving ecological protective concentration (EPC) was previously suggested in USA, Australia, New Zealand, Canada, and Netherland. This study suggested the EPC of cadmium (Cd) based on the PERA to be suitable to Korean aquatic ecosystem. First, we collected reliable ecotoxicity data from reliable data without restriction and reliable data with restrictions. Next, we sorted the ecotoxicity data based on the site-specific locations, exposure duration, and water hardness. To correct toxicity by the water hardness, EU's hardness corrected algorithm was used with slope factor 0.89 and a benchmark of water hardness 100. EPC was calculated according to statistical extrapolation method (SEM), statistical extrapolation $method_{Acute\;to\;chronic\;ratio}$ ($SEM_{ACR}$), and assessment factor method (AFM). As a result, aquatic toxicity data of Cd were collected from 43 acute toxicity data (4 Actinopterygill, 29 Branchiopoda, 1 Polychaeta, 2 Bryozoa, 6 Chlorophyceae, 1 Chanophyceae) and 40 chronic toxicity data (2 Actinopterygill, 23 Branchiopoda, 9 Chlorophyceae, 6 Macrophytes). Because toxicity data of Cd belongs to 4 classes in taxonomical classification, acute and chronic EPC (11.07 ${\mu}g/l$ and 0.034 ${\mu}g/l$, respectively) was calculated according to SEM technique. These values were included in the range of international EPCs. This study would be useful to establish the ecological standard for the protection of aquatic ecosystem in Korea.

• 대한안전경영과학회지
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• 제16권2호
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• pp.63-70
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• 2014

As preventive measures have received tremendous attention to prevent any possible accident in advance, many work places have introduced safety and health management systems. However despite of this government's effort, the industrial accident rate of small-scale businesses with less than 50 employees does not decline, which is mainly because the projects are not differentiated according to the risk level of individual business. To evaluate the risk level of small-scale businesses with less than 50 employees and then establish effective safety and health management systems according to the risk level, this study has conducted the following processes. The small-scale businesses with less than 50 employees were evaluated through accident type, and potential accident risk factor was evaluated through location, business type, and business size. The results of this analysis are expected to make contribution to improving the effectiveness of the safety and health management supports to small-scale businesses with less than 50 employees.

• 한국융합학회논문지
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• 제9권6호
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• pp.271-277
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• 2018

이 연구의 목적은 우리나라 지역거주 노인의 낙상 리스크를 평가하는 문항을 선정하고 유효성을 검토하는데 있다. 낙상위험 평가는 선행연구를 참고로 '낙상잠재성', '신체기능', '질병과 신체증상', '환경', '행동과 성격'의 5가지 요인으로 구분하였으며 내용타당성 검증, 교차분석 및 요인분석 결과에 따라 총 44개 문항으로 구성하였다. 한국형 낙상위험 평가척도는 심각한 사회문제로 인식되고 있는 노인의 낙상문제를 개선하고 개인의 낙상예방에 중요한 정보를 제공하는데 유용한 도구로 사용될 수 있을 것이다.

• 한국전자통신학회논문지
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• 제11권8호
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• pp.817-826
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• 2016

생활공간에서 안전을 확보하는 것은 중요하다. 본 연구에서는 기존의 지역별 시간별 사건발생 빈도 기반의 위험 알림 서비스에서 더 확장된 위험도 산출 방안을 제안한다. 시간외에도 생활공간의 조도, 유동인구 뿐 아니라 개인의 상태까지 위험도 산출에 포함하였다. 기존의 확률기반 증거이론은 상황과 관련있는 요소의 수가 증가할 때, 계산량은 급증하는 문제가 있는데 이를 피하기 위하여 퍼지이론을 도입하여 확장성을 확보할 수 있었다. 제안한 산출 방안으로 위험도를 산출한 계산 결과가 언어적 형용 표현까지 가능함을 볼 수 있었다.

• Toxicological Research
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• 제18권1호
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• pp.23-29
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• 2002

Disodium disulphite, the HPV chemical, was assigned to Korea in order to implement OECD SIDS program in 1999. It was produced about 3,200 ton/year in 1998. This report evaluates the toxic potency of disodium disulphite based on the environmental and mammalian effects as well as human exposure. Oral $LD_{50}$ in rats is 1,540 mg/kg b.w. and effects was observed to the stomach, liver and the GI track that was filled with blood. For repeated dose toxicity, the predominant effect was the induction of stomach lesion due to local irritation. The no observed adverse effect lever for local (stomach irritation) was about 217 mg/kg bw/day. There is no evidence that disodium disulphite is genotoxic in vivo. No reproductive or developmental toxicty of disodium disulphite was observed for the period up to 2 yr and over three generation. In humans, urticaria and asthma with itching, edema, rhinitis, and nasal congestion were reported. Disodium disulphite is unlikely to induce respiratory sensitization but may enhance symptom of asthma in sensitive individuals. This chemical would be mainly transported to water compartment when released to environmental compartments since it is highly water soluble (470 g/l at 20). Low K oc (2.447) indicates disodium disulphite is so mobile in soil that it may not stay in the terrestrial compartment. The chemical has been tested in a limited number of aquatic species. hem acute toxicity test to fish, 96 hr-$LC_{50}$ was > 100 mg/1. For algae, 72 hr-$XC_{50}$ was 48.1 mg/1. For daphnid, the acute toxicity value of 48 hr-$EC_{50}$ was 88.76 mg/1, and chronic value of 21day-NOEC was > 10 mg/1. Therefore, PNEC of 0.1 mg/l for the aquatic organism was obtained from the chronic value of daphnid using the assessment factor of 100. Based on these data the disodium disulphite was recommended as low priority for further post-SIDS work in OECD.

• Toxicological Research
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• 제18권1호
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• pp.13-22
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• 2002

In Korea, 2,320 tonnes of acetanilide were mostly wed as intermediates for synthesis in phar-maceuticals or additives in synthesizing hydrogen peroxide, varnishes, polymers and rubber. Only small amount of 120 kg were wed as a stabilizer for hydrogen peroxide solution for hair colouring agents in 1998. Readily available environmental or human exposure data do not exist in Korea at the present time. However, potential human exposures from drinking water, food, ambient water and in work places are expected to be negligible because this chemical is produced in the closed system in only one company in Korea and the processing factory is equipped with local ventilation and air filtering system. Acetanilide could be distributed mainly to water based on EQC model. This substance is readily biodegradable and its bioaccumulation is low. Acute toxicity of acetanilide is low since the L $D_{50}$ of oral exposure in rats is 1,959 mg/kg bw. The chemical is not irritating to skin, but slightly irritating to the eyes of rabbits. horn repeated dose toxicity, the adverse effects in rats were red pulp hyperplasia of spleen, bone marrow hyperplasia of femur and decreased hemoglobin, hematocrit and mean corpuscular hemoglobin concentration. The LOAEL for repeated dose toxicity in rats was 22 mg/kg/day for both sexes. Acetanilide is not considered to be genotoxic. In a reproductive/developmental toxicity study, no treatment-related changes in precoital time and rate of copulation, impregnation, pregnancy were shown in all treated groups. The NOAELs for reproduction and developmental toxicity (off-spring toxicity) are considered to be 200 mg/kg bw/day and 67 mg/kg bw/day, respectively. Ecotoxicity data has been generated in a limited number of aquatic species of algae (72 hr- $E_{b}$ $C_{50}$; 13.5 mg/l), daphnid (48hr-E $C_{50}$ > 100 mg/l) and fish (Oryzias latipes, 96hr-L $C_{50}$; 100 mg/l). Form the acute toxicity values, the predicted no effect concentration (PNEC) of 0.135 mg/1 was derived win an assessment factor of 100. On the basis of these data, acetanilide was suggested as currently of low priority for further post-SIDS work in OECD.in OECD.D.

• 해양환경안전학회지
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• 제19권4호
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• pp.375-381
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• 2013

해상교통환경의 위험도를 평가하기 위해서는 위험도를 구성하고 있는 위험요소들을 명확히 식별하고, 식별된 위험요소들을 평가할 수 있는 기준을 마련하여야 한다. 한편 이러한 각 위험요소들의 위험수준의 합으로 전체 위험도를 나타낼 수 있으므로, 각 위험요소가 전체 위험도에서 차지하는 비중인 상대적 중요도가 분석되어야 한다. 본 연구는 선행연구에서 국내 외 해상교통환경 위험도 평가모델들의 검토를 통하여 제시된 국내 해상교통환경의 위험도를 구성하는 20가지 위험요소와 평가기준 및 해상교통전문가 집단에 의한 설문조사를 통하여 계층분석적 의사결정법으로 분석한 각 위험요소의 상대적 중요도를 바탕으로, 국내 목포항 및 그 진입수로에 대한 해상교통환경의 위험도를 평가하였다. 목포항 및 그 진입수로는 비교평가를 위하여 총 4개의 해역으로 구분하여 분석하였으며, 분석결과 위험요소 해수운동 복잡성 예인선 도선사 선박교통관제 등에서 위험수준이 높게 나타난 정등해 항로의 위험도가 가장 높게 평가되었다. 이러한 평가결과는 동일한 해역에서 본 연구와는 다른 정성적 혹은 정량적 위험도 분석기법을 이용한 연구들의 평가결과와 대체로 일치하였다.

• 한국수자원학회논문집
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• 제56권10호
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• pp.667-678
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• 2023

본 연구에서는 단순한 형상의 지하역사를 대상으로 준3차원 침수 흐름 시뮬레이션을 수행하였으며, 우수유입지점 수와 우수 유입량 변화에 따른 침수 흐름 특성 및 침수 위험도를 분석했다. 침수 해석 결과로부터 보행 안정성 평가를 위한 한계유속을 계산하여 미끄러짐 및 전도 사고 발생 가능 영역을 분석했다. 그 결과, 미끄러짐 사고는 침수계단에서 발생할 가능성이 있고 전도 사고는 침수계단과 지하2층 계단 주변에서 발생할 우려가 있었다. 침수 위험도에 대한 세부적 판단을 위해 4단계로 침수 위험도를 평가하는 Flood Hazard Degree (FD)와 3단계로 평가하는 Flood Intensity Factor (FIF)를 적용했다. 그 결과, FD가 FIF에 비해 더 넓은 영역에서 침수 흐름에 의한 위험이 있는 것으로 판단했다. 한계비력, 미끄러짐 및 전도 사고 발생 한계유속, FD, FIF 방법으로 평가한 침수 위험 발생 영역을 비교했을 때 한계비력은 다른 평가 방법에 비해 침수 위험 영역을 과대 산정했고, FIF는 과소산정하는 결과를 나타냈다. 또한 모든 평가 방법을 고려했을 때 우수 유입량이 우수유입지점 수보다 침수 위험도 평가 결과에 지배적 영향을 미쳤다. 또한 동일한 방향으로 침수 흐름을 일으키는 우수 유입 조건 보다 서로 충돌하는 침수 흐름을 일으키는 조건에서 침수 위험도가 증가했다.