• 대한안전경영과학회지
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• 제8권2호
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• pp.61-70
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• 2006

The likelihood of failure by the corrosion of high temperature $H_2S/H_2$, which affect to a risk of facilities, was analyzed through the risk based-inspection using API-581 BRD. We found that the corrosion rate was increased as temperature and $H_2S$ concentration were increased. Also, the technical module subfactor(TMSF) was increased as an used you increased, material thickness decreased, inspection number decreased, and inspection effectiveness increased. In these conditions, the maximum value of TMSF was not varied, but the TMSF was sensitively varied at low temperature for high concentration of $H_2S$.

• 대한안전경영과학회지
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• 제9권1호
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• pp.65-76
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• 2007

The likelihood of failure for the stress corrosion cracking (SCC) of caustic cracking, which affect to a risk of facilities, was analyzed through the risk based-inspection using API-581 BRD. We found that SCC of the caustic cracking was occurred above 5 % NaOH concentration, and the technical module subfactor (TMSF) was maximized for above 50 % concentration. The heat traced and monitoring were not sensitive to the TMSF with NaOH concentration and temperature. But the steam out was more of less affect minimum value of the TMSF. Also, the inspection number, the inspection effectiveness, and the year since inspection were very sensitive to the TMSF with NaOH concentration and temperature. Therefore, the plan of next inspection will be established with compositively considering those at once.

• 대한안전경영과학회지
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• 제7권4호
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• pp.101-110
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• 2005

The likelihood of failure for the thinning of high temperature sulfide and naphthenic acid corrosion, which affect to a risk of facilities, was analyzed through the risk based inspection using API-581 BRD. We found that the corrosion rate was increased with increasing temperature and total acid number(TAN). And maximum value of the technical module subfactor(TMSF) was not varied with operating condition, but the TMSF was sensitively changed at the range of low temperature, low flow rate, and high TAN. Also, the TMSF was increased as an used year and inspection effectiveness increased, but it was increased as thickness, inspection number, and over design decreased.

• 대한예방의학회:학술대회논문집
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• 대한예방의학회 1994년도 교수 연수회(환경)
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• pp.426-430
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• 1994

The assessment of exposure is an important component of the risk assessment process. Exposure information is used in risk assessment in at least two ways: 1) in the identification of hazards and the epidemiologic research investigating exposure-response relationships and 2) in the development of population exposure estimates. In both of these cases, the value of a chemical risk assessment is enhanced by improvements in the quality of exposure assessments. The optimum exposure assessment is the direct measurement of population exposure; however, such measurements are rarely available. Recent developments in methods for exposure assessment allow estimates to be made that are valid representations of actual exposure. The use of these exposure estimates to classify exposures correctly enhances the likelihood that causal associations between exposure and response will be correctly identified and that population risks will be accurately assessed.

• 대한수의학회지
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• 제45권2호
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• pp.223-231
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• 2005

A quantitative risk assessment tool was used to provide estimates of the probability that foot-and-mouth (FMD) virus-contaminated, smuggled animal products are fed to susceptible swine in Korea. Sensitivity analyses were conducted to attempt to distinguish between parameter uncertainty and variability, using different assumptions on the effect of cooking at home, the effect of the fresh meat, and the effect of heat treatment at garbage processing facility. The median risk estimate was about 20.1% with a mean value of 27.4%. In a scenario regarding all beef and pork were considered as fresh meat the estimated median risk was 3.4%. The risk was greatly dependent on the survival parameters of the FMD virus during the cooking or heat treatment at garbage processing facility. Uncertainty about the proportion of garbage that is likely contaminated with FMD had a major positive influence on the risk, whereas conversion rate representing the size of a load had a major negative effect. This model was very useful in assessing the risk explored. However, the model also requires enhancements, such as the availability of more accurate data to verify the various assumptions considered such as FMD prevalence in a specific country, proportion of garbage which is recycled as feed, proportion of food discarded as garbage. Other factors including the effect of selection of animals for slaughter, ante- and post-mortem inspection, the domestic distribution of the smuggled products, and susceptible animals other than pigs, are need to be taken into account in the future model development.

• 대한방사선기술학회지:방사선기술과학
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• 제35권1호
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• pp.35-44
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• 2012

서울소재 'S'병원에서 근무중인 방사선사를 대상으로 병원 근무경력 및 CT검사실 근무 경험 유 무, 현재 사용하고 있는 방사선 선원의 종류에 따른 CT검사와 일반촬영검사의 방사선 선량과 위험성에 관한 인식도 조사를 통해 CT검사의 위험성에 대한 각성을 위한 기초자료로 활용하고자 한다. 영상의학과에 근무하는 방사선사 중 131명을 대상으로 설문지를 통해 연구가설 검정을 위한 자료를 수집하였고, 설문문항의 Cronbach @계수는0.825988과0.767161로 나타났으며, p-value의 기각률은<0.05로 하였다. 연구가설검정을 위해 SAS 9.1(SAS Institute Inc., Cary, NC, USA.)통계패키지를 이용하여 Mann-Whitney test와 Kruskai-Wallis test, Two sample T-test, Two sample T-test with Bonferroni's Correction, One-way ANOVA 통계분석방법 등을 이용하였다. CT검사와 일반촬영의 선량에 관한 가설의 각 p-value 값은 0.2291~0.9663의 범위로 나타났고, CT검사와 일반촬영검사의 위험성에 관한 가설의 각 p-value 값은 0.1924~1.0000의 범위로 나타났다. 모든 연구가설의 p-value값이 기각률(<0.05)을 상위하여 나타났으며, 현재 'S'병원에 근무중인 방사선사들은 근무경력 및 CT검사실 근무경력 유무, 현재 사용하는 방사선 선원의 종류에 관계없이 일반촬영 보다 CT검사가 선량이 많으며, 위험하다고 인식하고 있는 것으로 나타났다.

• 대한암한의학회지
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• 제24권2호
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• pp.1-11
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• 2019

Objectives : We investigated whether a single center nutrition screening tool (Kyunghee Neo Nutrition Risk Screening, KNNRS) can predict survival in patients with metastatic cancer. Methods : We retrospectively reviewed data of inpatients with metastatic cancer from April 2016 to August 2019. Data on demographic and clinical parameters were collected from electronic medical records, and overall survival was estimated using the Kaplan-Meier method. Stepwise Cox regression analysis was used to determine factors associated with survival. Patients with a KNNRS score of 0 to 3 were classified as "no-risk", 4 to 10 as "low-risk", and 11 to 20 as "high-risk". Results : Total 105 patients were included in the study. According to nutritional screening at baseline, 25 patients (23.8%, median age 57.0) were classified as ""no risk"" group; 80 patients (76.2%, median age 68.5) as "low risk" group; No patients as "high risk" group. Predictors of survival were Eastern Cooperative Oncology Group Performance Status score of 3 or 4 (hazard ratio [HR] = 1.93; 95% confidence interval [CI] = 1.21-3.10), hemoglobin less than 10 g/dL (HR = 1.97; 95% CI = 1.25-3.10) and C-reactive protein more than 1.0 mg/dL (HR = 1.95; 95% CI = 1.21-3.13). Kaplan-Meier survival analysis showed significant differences in the survival between KNNRS groups: ""no risk"" group: 6.1 ± 1.4 months (95% CI = 3.37-8.83); ""low risk"" group: 3.4 ± 0.9 months (95% CI = 1.5-5.37). Conclusions : Nutritional status according to KNNRS wasn't significant predictor of survival for patients with metastatic cancer. Improvement of KNNRS score thresholds is needed.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2008년도 정기학술발표대회 논문집
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• pp.517-520
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• 2008

최근 국내에서 대두되고 있는 도시재생 개발사업은 신도시 및 기존 시가지를 중심으로 공공기관의 주도하에 이루어지고 있다. 이러한 개발사업들은 사전 평가 단계에서의 위험요인 관리가 사업의 성공과 부가가치 창출에 중요한 요인임에도 불구하고 안전관리 수준에서 머물고 있다. 이는 위험요인들을 분석할 수 있는 다양한 위험 분석 기법들에 대한 부정확한 이해 및 그 중요도를 파악하지 못하고 있으며, 단계별 적절한 분석 기법의 적용이 미흡하기 때문이다. 따라서 본 연구에서는 개발 사업에 대한 전반적인 이해와 개발 사업 사전평가 단계에서의 구성 및 정의, 사전평가 단계에서 적용될 수 있는 위험분석기법들에 대한 정의 및 분석을 통해 사전평가 단계에서 나타날 수 있는 다양한 위험요인들을 보다 효과적으로 관리할 수 있는 위험분석기법들을 마련하고자 한다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.1
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• pp.435-440
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• 2006

The Reduced Vertical Separation Minimum (RVSM), which is the reduced minimum from 2,000 ft to 1,000 ft at flight levels (FL) between 290 and FL410 inclusive, was implemented in 30 September 2005 within the Japanese domestic airspace. Prior to the implementation, safety assessment for the airspace in assumed RVSM environments was carried out. Some model parameter values of collision risk model were estimated using flight plan (progress) data and radar data. An estimate of vertical collision risk including operational risk was calculated using these together with given parameter values. The results obtained from this analysis are as follows. (1) Contribution of the vertical collision risk for the crossing routes is about 9 percents of the total technical risk. (2) The estimate of the collision risk is $4.1{\times}10^{-9}$ [fatal accidents / flight hour] and the value is smaller than a maximum allowable level of collision risk, i.e. $5{\times}10^{-9}$ [fatal accidents / flight hour], called the Target Level of Safety.

• Wind and Structures
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• 제37권4호
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• pp.275-287
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• 2023

Subgrade differential settlement of high-speed railways was a pivotal issue that could increase the risk of trains operation. The risk will be further increased when trains in the subsidence zone are affected by crosswinds. In this paper, the computational fluid dynamics (CFD) model and finite element (FE) model were established, and the data transmission interface of the two models was established by fluid-solid interaction (FSI) method to form a systematic crosswind-train-track-subgrade dynamic model. The risk of high-speed train encountering crosswind in settlement area was analyzed. The results showed that the aerodynamic force of the trains increased significantly with the increase in crosswind speed. The aerodynamic force of the trains could reach 125.14 kN, significantly increasing the risk of derailment and overturning. Considering the influence of crosswind, the risk of train operation could be greatly increased. The safety indices and the wheel-rail force both increased with the increase of the wind speed. For the high-speed train running at 350 km/h, the warning value of wind speed was 10.2 m /s under the condition of subgrade settlement with wavelength of 20 m and amplitude of 15 mm.