• Journal of the Korean Institute of Gas
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• v.7 no.4 s.21
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• pp.30-35
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• 2003

Product liability(PL) law imposes the liability on manufacturer or wholesaler when the product defects cause harm to consumers of the products or any other parties in their lives, bodies, or properties. In Korea, the law of product liability was enforced in July 2002. In this study the Product Liability Response System of chemical products was developed by using Failure Mode and Effect Analysis(FMEA). For a case study peformed for N,N-Dimethylethylamine. First, product information was gathered through Material Safety Data Sheet(MSDS)and which considered as an instruction manual of chemical product. And an effect caused by product defects is analyzed by FMEA to get Risk Priority Number(RPN) which is calculated by multiplying of severity, occurrence, and detection of the defects. Then hazard was estimated quantitatively by RPN.

• Journal of Radiation Protection and Research
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• v.26 no.3
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• pp.203-206
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• 2001

The mathematical processing (unfolding) of pulse height spectra from a scintillation detector helps to calculate the photon fluence rate energy distribution in a measured photon field. The data processing is based on the knowledge of detection system response function and directional dependence respectively. The experimental results of the photon fields measurements in the vicinity of the spent fuel temporary storage and inside the storage hall are presented. The containers Castor 440 are used for temporary storing of the burnt up fuel assemblies in the Czech nuclear power plant Dukovany. A set of periodical measurements was performed in order to get basic information on the time dependence of the photon fields spatial distributions and spectral characteristics in the temporary storage hall and its vicinity. The photon fields were measured by the scintillation system. The obtained photon fields spatial distributions and spectral characteristics present the information on the radiation hazard in the storage.

• Journal of the Korean Association of Geographic Information Studies
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• v.21 no.4
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• pp.191-201
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• 2018

Recently, the frequency of heavy rainfall is increasing due to the effects of climate change, and heavy rainfall in urban areas has an unexpected and local characteristic. Floods caused by localized heavy rains in urban areas occur rapidly and frequently, so that life and property damage is also increasing. It is crucial how fast and precise observations can be made on successful flood management in urban areas. Local heavy rainfall is predominant in low-level storms, and the present large-scale radars are vulnerable to low-level rainfall detection and observations. Therefore, it is necessary to introduce a new urban flood forecasting system to minimize urban flood damage by upgrading the urban flood response system and improving observation and forecasting accuracy by quickly observing and predicting the local storm in urban areas. Currently, the WHAP (Water Hazard Information Platform) Project is promoting the goal of securing new concept water disaster response technology by linking high resolution hydrological information with rainfall prediction and urban flood model. In the WHAP Project, local rainfall detection and prediction, urban flood prediction and operation technology are being developed based on high-resolution small radar for observing the local rainfall. This study is expected to provide more accurate and detailed urban flood warning system by enabling high-resolution observation of urban areas.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.18 no.6
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• pp.251-261
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• 2019

The importance of autonomous driving systems that utilize V2X services such as V2V(Vehicle to Vehicle) and V2I(Vehicle to Infrastructure) for safer and more comfortable driving is increasing with the recent development of autonomous vehicles. Partly autonomous vehicles based on environmental sensors have limitations for predicting and determining areas beyond the recognition distance of the mounted sensors and in response to atypical objects that are difficult to detect. Therefore, it is important to utilize the V2X service to improve the limit of sensor detection performance and to make driving safer and more comfortable. However, there may be an accident risk of autonomous vehicles due to incorrect information provided by V2X. Thus, the application of technology to prevent this needs to be considered. In this pater, we used the ISO-26262 Part3 Process and performed HARA (Hazard Analysis and Risk Assessment) to derive the risk sources of autonomous vehicles due to V2I malfunctions by using the communication between vehicles and infrastructure among V2X. We also developed ASIL ratings based on the simulations and real vehicle tests of the malfunctions of major cases of usnig V2I.

• Transactions of the Korean hydrogen and new energy society
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• v.20 no.5
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• pp.378-383
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• 2009

Hydrogen is the primary fuel in fuel cell systems. Because of high inflammation and explosion possibility of hydrogen, fuel cell systems require safety measures to prevent hydrogen hazard upon leakage. In this study, a model enclosure was made by referring to a commercial residential fuel cell system and hydrogen leakage experiments and computational simulations were conducted therein. Hydrogen was injected into the cavity through leakage holes located at the bottom while its flow rate was precisely controlled using MFC. The transient sensor signals from hydrogen sensors installed inside the enclosure were recorded and analyzed. The hydrogen sensor signals showed different delay times depending on their position relative to a leakage point, which indicated that hydrogen generally moves upward and accumulates at the upper region of a closed cavity. The inflammable regions with hydrogen concentration over 4% LEL were observed to locate near the leakage hole initially, and broaden towards the upper cavity region afterward. The simulation result showed that detection time at the hydrogen sensor was similar to the pattern of experimental results. However, the maximum concentration of hydrogen had a gap between experiment and simulation at detect point due to measurement errors and reaction rate.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.7
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• pp.4261-4265
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• 2013

Increasing scientific evidence suggests that ribonucleotide reductase M1 (RRM1) may be a powerful predictor of survival in patients with pancreatic cancer treated with adjuvant gemcitabine-based chemotherapy after operative resection, but many existing studies have yielded inconclusive results. This meta-analysis aimed to assess the prognostic role of RRM1 in predicting survival in patients with pancreatic cancer treated with gemcitabine. An extensive literature search for relevant studies was conducted on PubMed, Embase, Web of Science, Cochrane Library, and CBM databases from their inception through May 1st, 2013. This meta-analysis was performed using the STATA 12.0 software and crude hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated. Eight clinical studies were included in this meta-analysis with a total of 665 pancreatic cancer patients treated with adjuvant gemcitabine-based chemotherapy, including 373 patients in the high RRM1 expression group and 292 patients in the low RRM1 expression group. Our meta-analysis revealed that high RRM1 expression was associated with improved overall survival (OS) of pancreatic cancer patients (HR=1.56, 95%CI=0.95-2.17, P<0.001). High RRM1 expression also was linked to longer disease-free survival (DFS) than low RRM1 expression (HR=1.37, 95%CI=0.25-2.48, P=0.016). In conclusion, our meta-analysis suggests that high RRM1 expression may be associated with improved OS and DFS of pancreatic cancer patients treated with adjuvant gemcitabine-based chemotherapy. Detection of RRM1 expression may be a promising biomarker for gemcitabine response and prognosis in pancreatic cancer patients.

• Transactions of the Korean Society of Automotive Engineers
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• v.24 no.1
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• pp.112-121
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• 2016

AFLS (Adaptive front lighting system) is being applied to improve safety in driving automotive at night. Safe embedded system design for controlling head-lamps is required to improve noise robust ECU hardware and software simultaneously by considering safety requirement of hardware-dependent software under severe environmental noise. In this paper, we propose an adaptive headlight controller with a newly-designed symmetric angle sensor compensator, especially based on the proposed steering-swivel angle lookup table to determine whether the current controlling target is safe. The proposed system includes an additional backup hardware to compare the system status and provides safe swivel-angle management using a controlling algorithm based on the pre-defined lookup table (LUT), which is a symmetric mapping relationship between the requested steering angle and expected swivel angle target. The implemented system model shows that the proposed architecture effectively detects abnormal situations and restores safe status of controlling the light-angle in AFLS operations under severe noisy environment.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.6
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• pp.1017-1023
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• 2017

Duration induced by freeway crashes has a critical influence on traffic congestion. In general, crash duration composes detection and verification, response, and clearance time. Of these, the crash clearance time determined by a crash clearance team has attracted considerable attention in the freeway congestion management since the interest of the first two time stages faded away with increasing ubiquitous mobile phone users. The objective of this study is to identify the critical factors that affect freeway crash clearance time using a Cox's proportional hazard model. In total, 6,870 crash duration data collected from 30 major Korean freeways in 2013 were used. As a result, it was found that crashes during the night, with trailer or larger size truck, and in tunnel section contribute to increasing clearance time. Crashes associated with fatality, completed damage of crashed vehicle (s), and vehicles' fire or rollover after crash also lead to increasing clearance time. Additionally, an increase in the number of vehicles involved resulted in longer clearance time. On the other hand, crashes in the vicinity of tollgate, by passenger car, during spring, on flat section, and of car-facility type had longer clearance time. On the basis of the results, this paper suggested some strategic plans and mitigation measures to reduce crash clearance time on Korean freeway systems.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.14
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• pp.5685-5689
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• 2014

Background: It is well known that smoking is a preventable factor for all-cause mortality; however, it is still questionable how many years after smoking cessation that people will have reduced risk for mortality, in particular in those with a high interest in their own health. We aimed to examine the association between time since quitting smoking and total mortality among past-smokers relative to current smokers. Materials and Methods: We enrolled 36,446 health examinees that voluntarily taken with diverse health check-up packages of high cost burden in 1995-2003 and followed them till death by 2004. The history of cigarette smoking consumption was collected using a self-administrative questionnaire at the first visit time. Mortality risk by smoking cessation years was analyzed using Cox's proportional hazard model. Results: Compared to non-smokers, male smokers over 15 pack-years had higher risk for total mortality (HR=1.60, 95%CI 1.23-2.14). The mortality risk in female smokers with same pack-years was more pronounced than that in male smokers (HR=2.83, 95%CI 1.17-7.04) despite a small number of cases. Compared to current smokers, a decrease of total mortality was observed among those who ceased smoking, and inverse dose-response was found with years after cessation: RR 0.98 (95%CI, 0.64-1.41) (<2 yrs), 0.60 (95%CI, 0.43-0.83) (3-9 yrs), and 0.58 (95%CI, 0.43-0.79) (${\geq}10$ yrs). Conclusions: A reduced risk of total mortality was observed after 3 years of smoking cessation. Our findings suggest that at least 3 years of smoking cessation may contribute to reduce premature mortality among Asian men.