• Nuclear Engineering and Technology
• /
• 제47권1호
• /
• pp.74-84
• /
• 2015

If a transient occurs in a nuclear power plant (NPP), operators will try to protect the NPP by estimating the kind of abnormality and mitigating it based on recommended procedures. Similarly, operators take actions based on severe accident management guidelines when there is the possibility of a severe accident occurrence in an NPP. In any such situation, information about the occurrence time of severe accident-related events can be very important to operators to set up severe accident management strategies. Therefore, support systems that can quickly provide this kind of information will be very useful when operators try to manage severe accidents. In this research, the occurrence times of several events that could happen during a severe accident were predicted using support vector machines with short time variations of plant status variables inputs. For the preliminary step, the break location and size of a loss of coolant accident (LOCA) were identified. Training and testing data sets were obtained using the MAAP5 code. The results show that the proposed algorithm can correctly classify the break location of the LOCA and can estimate the break size of the LOCA very accurately. In addition, the occurrence times of severe accident major events were predicted under various severe accident paths, with reasonable error. With these results, it is expected that it will be possible to apply the proposed algorithm to real NPPs because the algorithm uses only the early phase data after the reactor SCRAM, which can be obtained accurately for accident simulations.

• 정신신체의학
• /
• 제12권1호
• /
• pp.66-75
• /
• 2004

연구목적: 교통사고 후 외상의 심각도와 정신과적인 증상들과의 관계를 알아보고자 하였다. 방 법: 교통사고 후 장해평가나 감정의 목적으로 1994년부터 2003년까지 입원한 134명의 환자를 대상으로 하였다. 입원 시 기록과, 정신과적인 증상들, 심리검사로는 MMPI, BAI, BDI, K-WAIS을 평가하였다. 초진기록에 의한 외상심각도를 측정하고 맥브라이드 기준법에 의한 노동능력 상실률도 구하였다. 통계학적으로는 SPSS-10을 이용한 t-test와 Pearson correlation analysis를 시행하였다. 결 과: 외상의 심각도가 심하지 않을 경우에 오히려 자살시도가 더 많았다. 또 우울, 히스테리, 강박증, 및 반사회성척도의 점수가 높았다. 외상이 심하지 않은 경우에 집중력의 장애, 지남력의 장애, 지능의 저하가 더 심했다. 외상의 심각도와 증상을 가장하는 척도간의 관계는 없었다. 결 론: 교통사고 후 사고당시의 외상의 심각도가 정신과적 증상을 심하게 일으키는데 일치하는 것은 아니었다. 오히려 신체적 외상이 심하지 않았던 환자들이 정신의학적 증상이 심각한 경우가 많아서 신체적 손상의 정도에 기준을 두고 정신과적 증상의 평가를 섣불리 예측하는 것을 주의해야 할 것으로 생각된다.

• 한국도로학회논문집
• /
• 제19권6호
• /
• pp.201-212
• /
• 2017

PURPOSES : The objective of this study is to identify the characteristics affecting traffic accidents that have occurred in 564 industrial complexes nationwide from 2011 to 2015. METHODS : The traffic accidents were specified using various factors such as industrial complex type (national VS. general), industrial complex degradation (old VS. non-old), location of complex (capital VS. non-capital), and traffic law violation (speeding, signal violation, and median invasion). The average number of crashes and accident ratio (fatal, severe, and both) in terms of characteristics of industrial complexes were calculated. With a sample of crashes of the industrial complexes for 5 years, statistical significances were tested to analyze and compare the differences based on industrial complex and traffic law characteristics using parametric and non-parametric methods. RESULTS : From statistical results, it is observed that the crash frequency occurring in old industrial complexes is three times higher than that in non-old industrial complexes. Old industrial complexes located in a capital area, old national industrial complexes, and old general industrial complexes are considerably related to higher crash frequency, but the fatal accident ratio appeared to have no statistical difference across industrial complex characteristics. Severe crashes are more likely to occur in non-old industrial complexes on an average. CONCLUSIONS : It is necessary to eliminate potential threats to roads and traffic in the same manner as illegal parking in industrial complexes through the restoration of old industrial complexes. To improve the efficiency of road infrastructure, efforts should be made to improve traffic safety in accordance with industrial characteristics such as planning and operation of relevant local government programs.

• Journal of Trauma and Injury
• /
• 제34권3호
• /
• pp.147-154
• /
• 2021

Purpose: We analyzed the characteristics and outcomes of patients with bicycle-related injuries at a regional trauma center in northern Gyeonggi Province as a first step toward the development of improved prevention measures and treatments. Methods: The records of 239 patients who were injured in different types of bicycle-related accidents and transported to a single regional trauma center between January 2017 and December 2018 were examined. This retrospective single-center study used data from the Korea Trauma Database. Results: In total, 239 patients experienced bicycle-related accidents, most of whom were males (204, 85.4%), and 46.9% of the accidents were on roads for automobiles. Forty patients (16.7%) had an Injury Severity Score (ISS) of 16 or more. There were 125 patients (52.3%) with head/neck/face injuries, 97 patients (40.6%) with injuries to the extremities, 59 patients (24.7%) with chest injuries, and 21 patients (8.8%) with abdominal injuries. Patients who had head/neck/face injuries and an Abbreviated Injury Score (AIS) ≥3 were more likely to experience severe trauma (ISS ≥16). In addition, only 13 of 125 patients (10.4%) with head/neck/face injuries were wearing helmets, and patients with injuries in this region who were not wearing helmets had a 3.9-fold increased odds ratio of severe injury (AIS ≥2). Conclusions: We suggest that comprehensive accident prevention measures, including safety training and expansion of safety facilities, should be implemented at the governmental level, and that helmet wearing should be more strictly enforced to prevent injuries to the head, neck, and face.

• Safety and Health at Work
• /
• 제13권3호
• /
• pp.279-285
• /
• 2022

Background; In the event of an industrial accident, the appropriate choice of hospital is important for worker health and prognosis. This study investigates whether the choice of hospital by the employer in the case of industrial accidents affects the prognosis of injured employees. Methods; Data from the 2018 Panel Study of Workers' Compensation Insurance in Korea were used in an unmatched case-controlled study. The exposure variable is "hospital selection by an employer," and the outcome variable is 'worker's disability." Odds ratios (ORs) were estimated by modified Poisson regression and adjusted for age, gender, underlying disease, injury severity, and workplace size and stratified by industrial classification. The group at increased risk was analyzed and stratified by age, gender, and area. Results; In the construction industry, hospital selection by the employer was significantly associated with increased risk of disability (adjusted OR 1.26; 95% confidence interval [CI]; 1.20-1.32) and severe disability (adjusted OR 1.38; 95% CI; 1.08-1.76) among the injured. Female and younger workers not living in the Seoul capital area were more at risk of disability and severe disability than those living in the Seoul capital area. Conclusions; Hospital selection by employers affects the prognosis of workers injured in an industrial accident. For protecting workers' health and safety, workplace emergency medical systems should be improved, and the selection of appropriate hospitals to supply treatment should be reviewed.

• 문화기술의 융합
• /
• 제9권3호
• /
• pp.625-632
• /
• 2023

최근 안전에 대한 사회적 관심의 증가로 인해 정부는 중대재해처벌법 시행, 중대재해 저감 로드맵 구축 등의 다양한 노력을 하고 있다. 특히, 50인 미만 사업장, 공사금액 1억 미만 공사현장 등의 소규모 사업장에서는 업무상 사고 재해의 80%이상 발생하고 있으며 이를 저감하기 위한 실질적인 노력이 필요한 실정이다. 소규모 사업장에서는 안전보건관리자 선임, 안전보건 관리 규정 등이 전부 또는 부분적으로 제외된 상태로 이를 보완하고자 재해예방전문기관의 기술지도를 의무적으로 받고 있다. 본 연구에서는 소규모 사업장 안전보건기술지원사업의 안전, 화학, 보건, 건설 등의 분야별 문제점을 설문조사를 통해 파악하고 개선방안을 제시하고자 하였다.

• Fisheries and Aquatic Sciences
• /
• 제27권1호
• /
• pp.7-16
• /
• 2024

Fishing is considered one of the most dangerous industries alongside mining that needs further efforts to improve safety. In this study, we have investigated safety management of the gillnet fishing industry in South Korea through identifying safety level and classifying common accident types from the statements of accident com-pensation insurance payments for the last 5 years (2016-2020). There were in total 3,895 accidents and 159 fatalities with an average accident frequency of 5.34 × 10^-2 per year per fisher and an average fatality of 2.18 × 10^-3 fishers per year. We have also identified that 62.4% of the accidents occurred during Fishing (FS), and the most common and the most severe accident type is Slips and Trips (ST) and Other (OT) marine accidents such as collision and capsizing, respectively. The hand was most frequently injured. Finally, the risk assessment indicated that most of the accident types of gillnet fishing in South Korea have unacceptable levels of risks, and it is urgent to implement improved safety measures to reduce accidents during gillnet fishing operation. The findings of this study are expected to provide valuable data to create a safer working environment for fishers working on gillnet fishing vessels.

• Journal of Korean Neurosurgical Society
• /
• 제29권2호
• /
• pp.196-202
• /
• 2000

Objective : This study was designed to evaluate the relationship between the initial neurosurgical or psychosocial factors and the psychosocial outcome. Patients and Methods : We analyzed 123 head-injured patients who were referred to the department of psychiatry for the evaluation of psychosocial function. We analyzed initial neurosurgical variables such as Glasgow Coma scale(GCS) score, skull fracture, CT finding, and psychosocial outcomes with regards to psychosis, personality change, depression, anxiety and IQ on Intelligence Scale. Results : Patients with mild head injury(GCS score 13-15, N＝94, 76.4%) had better recovery rate on Glasgow Outcome Scale(GOS), less personality change than those with moderate or severe head injury. However, depression, anxiety and intelligence were not significantly different between two groups. The skull fracture(N＝37, 30.1%) did not influence on the psychosocial outcome with reference to personality change, depression, anxiety and intelligence. The patients with abnormal CT findings(N＝64, 52%) had lower recovery rate on GOS, more frequent tendency in psychosis, personality change and severe depression, less frequent in anxiety and mild depression, than patients with normal CT finding. However, levels of intelligence were not different between two groups. The patients with industrial accidents(IA) had lower educational level, milder head injury, more delay for the psychiatric evaluation (longer treatment period) than those with motor vehicular accidents(MVA). The psychosocial outcome with reference to personality change, depression, anxiety, intelligence were not different between two groups. Conclusion : These findings indicate that the more severe initial trauma, the poorer psychosocial outcome. However, it was frequently observed that patients with mild head injury suffered from mild anxiety and depression. Therefore mild head injury appeared to be more complicated by psychosocial stressors. The patients with IA, despite the fact that initial head injury was mild, required longer treatment period than MVA.

• 한국입자에어로졸학회지
• /
• 제10권4호
• /
• pp.137-154
• /
• 2014

문헌조사를 통해 그동안 선행연구로부터 밝혀진 방사성 에어로졸의 특성을 종합하고 정리하였다. 가상사고 실험 중 각재계통 및 원자로건물에서 측정한 에어로졸의 특성, 냉각재계통 및 원자로건물에서의 방사성 에어로졸 거동 해석을 위해 사용된 모델 에어로졸의 특성, 공학적 안전설비 성능평가를 위한 실험에 사용된 모델 에어로졸의 특성 등과 관련한 선행연구 내용을 종합해 볼 때, 원전사고 시 발생하는 에어로졸의 MMD는 $0.1{\sim}5{\mu}m$, GSD는 1.33~2.9, 에어로졸 농도는 $0.06{\sim}132g/m^3$의 범위를 보였다. 향후 공학적 안전설비의 설계를 위한 MMD와 GSD의 대표값은 대략 $1.5{\mu}m$와 1.8 내외라고 할 수 있으며, 에어로졸 농도는 대략 $10g/m^3$을 대표값으로 볼 수 있다.

• Nuclear Engineering and Technology
• /
• 제48권1호
• /
• pp.16-25
• /
• 2016

In severe loss of coolant accidents (LOCA), similar to those experienced at Fukushima Daiichi and Three Mile Island Unit 1, the zirconiumalloy fuel claddingmaterials are rapidlyheateddue to nuclear decay heating and rapid exothermic oxidation of zirconium with steam. This heating causes the cladding to rapidly react with steam, lose strength, burst or collapse, and generate large quantities of hydrogen gas. Although maintaining core cooling remains the highest priority in accident management, an accident tolerant fuel (ATF) design may extend coping and recovery time for operators to restore emergency power, and cooling, and achieve safe shutdown. An ATF is required to possess high resistance to steam oxidation to reduce hydrogen generation and sufficient mechanical strength to maintain fuel rod integrity and core coolability. The initiative undertaken by Electric Power Research Institute (EPRI) is to demonstrate the feasibility of developing an ATF cladding with capability to maintain its integrity in $1,200-1,500^{\circ}C$ steam for at least 24 hours. This ATF cladding utilizes thin-walled Mo-alloys coated with oxidation-resistant surface layers. The basic design consists of a thin-walled Mo alloy structural tube with a metallurgically bonded, oxidation-resistant outer layer. Two options are being investigated: a commercially available iron, chromium, and aluminum alloy with excellent high temperature oxidation resistance, and a Zr alloy with demonstratedcorrosionresistance.Asthese composite claddings will incorporate either no Zr, or thin Zr outer layers, hydrogen generation under severe LOCA conditions will be greatly reduced. Key technical challenges and uncertainties specific to Moalloy fuel cladding include: economic core design, industrial scale fabricability, radiation embrittlement, and corrosion and oxidation resistance during normal operation, transients, and severe accidents. Progress in each aspect has been made and key results are discussed in this document. In addition to assisting plants in meeting Light Water Reactor (LWR) challenges, accident-tolerant Mo-based cladding technologies are expected to be applicable for use in high-temperature helium and molten salt reactor designs, as well as nonnuclear high temperature applications.