• 한국산업보건학회지
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• 제21권2호
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• pp.73-81
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• 2011

The purpose of this study was to obtain scientific information regarding classification and health hazards that may result from a 13 weeks inhalation exposure of isoprene in Sprague-Dawley (SD) rats. The testing method was conducted in accordance with OECD guidelines for the testing of chemicals No. 413. The Rats were divided into 4 groups (10 male and 10 female rats in each group) and exposed to 0, 360, 1,620, 7,300 ppm isoprene in each exposure chamber for 6 h/day, 5 days/week, for 13 weeks. As a result, there were no mortality or abnormality during the period of study and did not show any significant changes of body weight. There were no dose response changes in urinalysis, hematological and serum biochemical value examination. Relative organ weight was increased significantly the right kidney in 7,300 ppm group of male rats. In female rats, relative organ weight of the left kidney and the both lungs in 1,620 ppm group and the left lung and the both kidneys in 7,300 ppm group were increased significantly. But the histopathological findings did not reveal any exposure-related changes. According to the above results, the no observable adverse effect level (NOAEL) of isoprene was 7,300 ppm (20.3 mg/L) in both male and female rats. In conclusion, Isoprene was not classified specific target organ toxicity of the 'Standard for Classification and Labeling of Chemical Substance and Material Safety Data Sheet' (Ministry of Employment and Labor, 2009).

• Nuclear Engineering and Technology
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• 제55권7호
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• pp.2438-2446
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• 2023

To cool down a nuclear reactor core and prevent the fuel damage without a pump-driven active component during any anticipated accident, the passive emergency core cooling system (PECCS) was designed and adopted in an advanced light water reactor, i-POWER. In this study, for a validation of the cooling capability of PECCS, thermal-hydraulic integral effect tests were performed with the ATLAS facility by simulating intermediate and small break loss-of-coolant accidents (IBLOCA and SBLOCA). The test result showed that PECCS could effectively depressurize the reactor coolant system by supplying the safety injection water from the safety injection tanks (SITs). The result pointed out that the safety injection from IRWST should have been activated earlier to inhibit the excessive core heat-up. The sequence of the PECCS injection and the major thermal hydraulic transient during the SBLOCA transient was similar to the result of the IBLOCA test with the equivalent PECCS condition. The test data can be used to evaluate the capability of thermal hydraulic safety analysis codes in predicting IBLOCA and SBLOCA transients under an operation of passive safety system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.2160_2161
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• 2009

본 논문에서는 최근 신축된 건축물의 수전실에 설치된 접지단자함 내부의 보호도체와 접지선의 접속실태, 접지방식 및 접지저항 측정용 보조전극의 매설 실태 등을 분석하였다. 또한, 측정용 보조전극의 매설 실태를 토대로 접지전극을 선정하여 보조전극의 위치 변화에 따른 접지저항의 오차를 측정 및 분석하였다.

• Environmental Analysis Health and Toxicology
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• 제22권1호
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• pp.91-101
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• 2007

The new chemicals are developed and circulated without the verified toxicity data. So, the accidents and occupational diseases, such as explosion, fire, suffocation about deadly poisons etc. are frequently to workers. Classifications of chemicals suited with guideline and an offer of correct chemical information data are the molt important thing for the establishment of suitable chemical management system. The GHS (Globally Harmonized System of classification and labeling of chemicals) is based with the chemical classifications and unification plan. The warning symbol and phrases are established for improvements of chemical information data system. According to these unified and improved systematic form of data, and the chemical information data, the workplaces will be presented many chemical safety and risk data correctly. In this paper, we will present constructions and accomplishment contents-based chemical management of workplace through development of chemical information data and the nice using for new chemical investigation and risk assessment of chemicals in workplaces.

• Nuclear Engineering and Technology
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• 제48권4호
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• pp.1015-1021
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• 2016

Structures, systems, and components (SSCs) important to safety of nuclear facilities shall be designed, fabricated, erected, and tested to quality standards commensurate with the importance of the safety functions. Although SSC classification guidelines for nuclear power plants have been well established and applied, those for research reactors have been only recently established by the International Atomic Energy Agency (IAEA). Korea has operated a pool-type research reactor (the High Flux Advanced Neutron Application Reactor) and has recently exported another pool-type reactor (Jordan Research and Training Reactor), which is being built in Jordan. Korea also has a plan to build one more pool-type reactor, the Kijang Research Reactor, in Kijang, Busan. The safety classification of SSCs for pool-type research reactors is proposed in this paper based on the IAEA methodology. The proposal recommends that the SSCs of pool-type research reactors be categorized and classified on basis of their safety functions and safety significance. Because the SSCs in pool-type research reactors are not the pressure-retaining components, codes and standards for design of the SSCs following the safety classification can be selected in a graded approach.

• Nuclear Engineering and Technology
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• 제55권5호
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• pp.1814-1820
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• 2023

Safety classification of systems, structures, and components (SSC) is an essential activity for nuclear reactor design and operation. The current regulatory trend is to require risk-informed safety classification that considers first, the severity, but also the frequency of SSC failures. While safety classification for nuclear power plants is covered in many regulatory and scientific publications, research reactors received less attention. Research reactors are typically of lower power but, at the same time, are less standardized i.e., have more variability in the design, operational modes, and operating conditions. This makes them more challenging when considering safety classification. This work presents the Integrated Risk-Informed Safety Classification (IRISC) procedure which is a novel extension of the IAEA recommended process with dedicated probabilistic treatment of research reactor designs. The article provides the details of probabilistic analysis performed within safety classification process to a degree that is often missing in most literature on the topic. The article presents insight from the implementation of the procedure in the safety classification for the MARIA Research Reactor operated by the National Center for Nuclear Research in Poland.

• 한국산업보건학회지
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• 제20권4호
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• pp.263-273
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• 2010

Occupational exposure to wollastonite can occur during its mining, processing and using. Wollastonite was analyzed for its physicochemical properties by transmission electron microscope and scanning electron microscope equipped with energy dispersive X-ray spectrometer. Wollastonite fibers were 3.3${\mu}m$ in diameter(av.) and were 30.5${\mu}m$ in length(av.). The atomic composition of wollastonite was Si 56.41% and Ca 43.59%. Respiratory toxicity of wollastonite has been studied in term sequential in Sprague-Dawely rats. UICC chrysotile (average diameter 0.03${\mu}m$, average length 2.93${\mu}m$) was applied as the positive control. The effects of 2mg wollastonite on respiratory system and pathological changes were evaluated after 1, 4, 8, 12 weeks instilled into rat lungs. Inflammation response broke out from 1 week after instilled with wollastonite and the pathological examination further showed increased legions of granulomatous inflammation after 4 weeks, but decreased granulomatous inflammation after 8 weeks, whereas chrysotile induced progressive interstitial granulomatous inflammation and fibrosis as a function of time.

• 전기학회논문지
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• 제62권12호
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• pp.1784-1791
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• 2013

Electrical safety technique is a disaster prevention technology to protect the life and property of the people and it has high correlation with all electricity industry. According to the latest statistics, loss of human life and property damage due to electrical fire have increased from 2011. Therefore, technological development for guarantee safety of electrical facilities for customer will become more important. In this paper, we drew priority and weigh for the electrical safety technology using analytic hierarchy process and present progress direction of each technology through Risk-Return assessment. We expect development of the research and development policies of government about electrical safety technology in a higher state and think that policymakers and experts will be more interested in these fields based on this paper.

• Safety and Health at Work
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• 제1권1호
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• pp.98-101
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• 2010

This study explored the health hazard of those exposed to methylene chloride by assessing its atmospheric concentration when a tear gas mixture was aerially dispersed. The concentration of methylene chloride ranged from 311.1-980.3 ppm (geometric mean, 555.8 ppm), 30 seconds after the dispersion started. However, the concentration fell rapidly to below 10 ppm after dispersion was completed. The concentration during the dispersion did not surpass the National Institute for Occupational Safety and Health 'immediately dangerous to life or health' value of 2,300 ppm, but did exceed the American Conference of Governmental Industrial Hygienists excursion limit of 250 ppm. Since methylene chloride is highly volatile (vapor pressure, 349 mmHg at $20^{\circ}C$), the post-dispersion atmospheric concentration can rise instantaneously. Moreover, the o-chlorobenzylidenemalononitrile formulation of tear gas (CS gas) is an acute upper respiratory tract irritant. Therefore, tear gas mixtures should be handled with delicate care.

• 대한안전경영과학회지
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• 제16권4호
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• pp.21-29
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• 2014

In this study, we recognize that the interest about construction safety and disaster increases, and check the status of current research about construction safety. And we obtain the direction of future researches and implications for development. For this study, we analyzed the published researches in the last 11 years about construction safety, and addressed annual trends and research topics for a lot of construction safety research. And the future prospects of construction safety research were analyzed with the latest news articles.