• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.19 no.3
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• pp.213-232
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• 2009

This document was prepared to review and summarize the analytical methods for airborne and bulk asbestos. Basic principles, shortcomings and advantages for asbestos analytical instruments using phase contrast microscopy(PCM), polarized light microscopy(PLM), X-ray diffractometer (XRD), transmission electron microscopy(TEM), scanning electron microscopy(SEM) were reviewed. Both PCM and PLM are principal instrument for airborne and bulk asbestos analysis, respectively. If needed, analytical electron microscopy is employed to confirm asbestos identification. PCM is used originally for workplace airborne asbestos fiber and its application has been expanded to measure airborne fiber. Shortcoming of PCM is that it cannot differentiate true asbestos from non asbestos fiber form and its low resolution limit ($0.2{\sim}0.25{\mu}m$). The measurement of airborne asbestos fiber can be performed by EPA's Asbestos Hazard Emergency Response Act (AHERA) method, World Health Organization (WHO) method, International Standard Organization (ISO) 10312 method, Japan's Environmental Asbestos Monitoring method, and Standard method of Indoor Air Quality of Korea. The measurement of airborne asbestos fiber in workplace can be performed by National Institute for Occupational Safety and Health (NIOSH) 7400 method, NIOSH 7402 method, Occupational Safety and Health Administration (OSHA) ID-160 method, UK's Health and Safety Executive(HSE) Methods for the determination of hazardous substances (MDHS) 39/4 method and Korea Occupational Safety and Health Agency (KOSHA) CODE-A-1-2004 method of Korea. To analyze the bulk asbestos, stereo microscope (SM) and PLM is required by EPA -600/R-93/116 method. Most bulk asbestos can be identified by SM and PLM but one limitation of PLM is that it can not see very thin fiber (i.e., < $0.25{\mu}m$). Bulk asbestos analytical methods, including EPA-600/M4-82-020, EPA-600/R-93/116, OSHA ID-191, Laboratory approval program of New York were reviewed. Also, analytical methods for asbestos in soil, dust, water were briefly discussed. Analytical electron microscope, a transmission electron microscope equipped with selected area electron diffraction (SAED) and energy dispersive X-ray analyser(EDXA), has been known to be better to identify asbestiform than scanning electron microscope(SEM). Though there is no standard SEM procedures, SEM is known to be more suitable to analyze long, thin fiber and more cost-effective. Field emission scanning electron microscope (FE-SEM) imaging protocol was developed to identify asbestos fiber. Although many asbestos analytical methods are available, there is no method that can be applied to all type of samples. In order to detect asbestos with confidence, all advantages and disadvantages of each instrument and method for given sample should be considered.

• Journal of Chest Surgery
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• v.49 no.4
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• pp.273-279
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• 2016

Background: The use of extracorporeal life support (ECLS) in the setting of cardiopulmonary resuscitation (CPR) has shown improved outcomes compared with conventional CPR. The aim of this study was to determine factors predictive of survival in extracorporeal CPR (E-CPR). Methods: Consecutive 85 adult patients (median age, 59 years; range, 18 to 85 years; 56 males) who underwent E-CPR from May 2005 to December 2012 were evaluated. Results: Causes of arrest were cardiogenic in 62 patients (72.9%), septic in 18 patients (21.2%), and hypovolemic in 3 patients (3.5%), while the etiology was not specified in 2 patients (2.4%). The survival rate in patients with septic etiology was significantly poorer compared with those with another etiology (0% vs. 24.6%, p=0.008). Septic etiology (hazard ratio [HR], 2.84; 95% confidence interval [CI], 1.49 to 5.44; p=0.002) and the interval between arrest and ECLS initiation (HR, 1.05 by 10 minutes increment; 95% CI, 1.02 to 1.09; p=0.005) were independent risk factors for mortality. When the predictive value of the E-CPR timing for in-hospital mortality was assessed using the receiver operating characteristic curve method, the greatest accuracy was obtained at a cutoff of 60.5 minutes (area under the curve, 0.67; 95% CI, 0.54 to 0.80; p=0.032) with 47.8% sensitivity and 88.9% specificity. The survival rate was significantly different according to the cutoff of 60.5 minutes (p=0.001). Conclusion: These results indicate that efforts should be made to minimize the time between arrest and ECLS application, optimally within 60 minutes. In addition, E-CPR in patients with septic etiology showed grave outcomes, suggesting it to be of questionable benefit in these patients.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.9 no.5
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• pp.38-48
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• 2010

Adverse weather (e.g. strong winds, snow and ice) will probably appear as a more serious and frequent threat to road traffic than in clear climate. Another consequence of climate change with a natural disastrous on road traffic is respond to traffic accident more the large and high-rise bridge zone, tunnel zone, inclined plane zone and de-icing zone than any other zone, which in turn calls for continuous adaption of monitoring procedures. Accident mitigating measures against this accident category may consist of intense winter maintenance, the use of road weather information systems for data collection and early warnings, road surveillance and traffic control. While hazard from reduced road friction due to snow and ice may be eliminated by snow removal and de-icing measures, the effect of strong winds on road traffic are not easily avoided. The purpose of the study described here, was to design of amber information the relationship between traffic safety, weather, user information on road weather and driving conditions in local-scale Geographic. The most applications are the optimization of the amber information definition, improvements to road surveillance, road weather monitoring and improved accuracy of user information delivery. Also, statistics on wind gust, surface condition, vehicle category and other relevant parameters for wind induced accidents provide basis for traffic control, early warning policies and driver education for improved road safety at bad weather-exposed locations.

• 전자공학회논문지 IE
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• v.49 no.1
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• pp.12-17
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• 2012

Fast development of ubiquitous technology prompted the broadening of the related application area. Application of ubiquitous techniques and system into the construction sites may give us many benefits. There are always a lot of hazard situations in construction sites, and the falling is known to have the high accident rate. To prevent the falling, there has been a lot of efforts including safety education and use of safety gears. In this study, we designed, fabricated and tested a system that can monitor the worker's safety and location informations in real time by using the wireless technology of TOA and RSSI. We used ATmegal28 that is popular in the industrial equipments as MCU and NanoPan 5357 module from Nanotron and CC2500 chipset from TI for radio circuits. We also used 3-axis accelerometer and pressure MEMS sensors to obtain the environmental information, and therefore to aquire the informations of the worker's movement and altitude. We used Labview software from National Instrument to monitor and control the system. We developed the system to send the warning alarms to the server operator and the workers when the workers in the danger zone did not wear the safety hook.

• Journal of Environmental Health Sciences
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• v.37 no.4
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• pp.279-288
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• 2011

Objectives: This study investigated the levels and components of floor-settled dust in two elementary schools located at different sites (one near the Shihwa industrial complex and the other in a rural area) in order to evaluate the amounts of trace metal elements (As, Cd, Co, Cr, Cu, Ni, Pb and Zn) and microorganisms. Methods: Over twenty settled-dust samples were collected from the two elementary schools. Trace metal elements were extracted from the dust using hydrochloric acid and nitric acid, and the amounts were measured by ICP-OES. Microbiological analysis was performed by bacterial culturing using R2A medium and denaturing gradient gel electrophoresis (DGGE). Results: The results showed that the amounts of three metal elements (Cr, Pb, and Zn) were significantly different between the schools (${\alpha}$=0.05, p<0.04). In addition, microbial communities in each school were highly correlated with one another. Among the identified microorganisms, a number of potentially opportunistic microorganisms, including antibiotic-resistant bacteria such as Acinetobacter baumannii, were found. Conclusions: This study will provide preliminary data for assessing levels and types of chemical and microbiological agents in elementary schools and for further evaluating human health risks associated with the agents.

• Journal of Korean Society of Forest Science
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• v.63 no.1
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• pp.51-60
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• 1984

Analysing the reports of disaster-related, average annual death of lives due to the meteorological disasters amounted to be 250, of which about 90 were due to landslide. According to the last 10-year reports, the average area of landslide occurred reaches 275 hectares per year in Korea. The total cost for rehabilitation could annually require more than about 2 billion Won (about US$ 2.5 million). The basic countermeasure policy against such heavy disasters should be definitely taken on prevention rather than rehabilitation after being damaged. However, prevention countermeasures against landslide-related disasters have not been strengthened in Korea although being important. Areas of high landslide hazard must be designated with increase in number from current 10 (35 cities and counties) to 17 (68 cities and counties included : Table 3). Number of regional Erosion Control Stations taking full charge of rehabilitating works on the damaged land resulted from landslide disaster has to increase from currently 15 stations to 25. The stone buttressed terrace structures on the hillside slopes, being typical erosion control measures in Korea have been recently recognized as one of the most effective rehabilitation measures for the land damaged by landslides.

• Environmental Analysis Health and Toxicology
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• v.10 no.1_2
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• pp.1-14
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• 1995

The purpose of this research is to assess the health risk of pollutants in drinking water and recommend the guidelines and management plans for maintaining good quality of drinking water. This study has been funded as a national project for three years from 1992 to 1995. This study(the second year, 1993-1994) was conducted to monitor 32 species of carcinogenic chemicals such as volatile organic compounds(VOCs), polynuclear aromatic hydrocarbons(PAHs), pesticides and heavy metals of drinking water at some area in six cities of Korea, and evaluate health risk due to these chemicals through four main steps of risk assessment in drinking water. In hazard identification, 32 species of carcinogenic chemicals were identified by the US EPA classification system. In the step of exposure assessment, sampling of raw, treated and tap water from the public water supply system had been conducted from 1993 to 1994, and 32 chemicals were analyzed. In dose-response assessment, cancer potencies, unit risk estimates and virtually safe doses of carcinogens were obtained by TOX-RISK (Version 3.1). In risk characterization of detected chemicals, health risk due to carcinogens such as vinyl chloride, carbon tetrachloride, dichloromethane, 1, 2-dichloromethane, chloroform, benzene and arsenic of tap water in several cities exceeded 10$^{-5}$ level. We suggest that non-regulated chemicals which exceed 10$^{-5}$ excess cancer risk level, such as vinyl chloride, carbon tetrachloride and 1, 2-dichloroethane, should be monitored periodically and be regulated by the Drinking Water Management Act, and database for exposure parameter of our own situation should be established.

• Korean Journal of Food Science and Technology
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• v.41 no.3
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• pp.334-338
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• 2009

To determine the contamination status of Sushi fish and rice, seventy-nine samples of Sushi were collected from wholesale markets and Japanese restaurants within the Seoul area and subsequently analyzed for food-borne pathogens. Total aerobic counts ranged from 4 to 6 log CFU/g for the sliced raw fish, and from 3 to 5 log CFU/g for the boiled rice. Higher levels of contamination were detected in bream and shrimp Sushi versus other types. Coliform counts of 3-4 log CFU/g were detected in the sliced raw fish, whereas levels in the boiled rice were one log CFU/g lower compared to the raw fish. The raw Sushi fish had higher amounts of contamination than the boiled rice, however, E.coli was not detected. The prevalence rates of pathogens, namely Staphylococcus aureus and Bacillus cereus, in the raw fish were 17% and 10%, respectively. Similarly, the prevalence rates in the boiled rice were 11% and 8% for S. aureus and B.cereus, respectively. Salmonella and Listeria monocytogenes were also detected; however, other pathogens such as Vibrio parahaemolyticus, Clostridium perfrigens, and Yersinia enterocolitica were not detected. Among the high contaminating pathogens, B.cereus was found in 13% of samples from the wholesale markets, while S.aureus was found in 30% of samples from the Japanese restaurants. Therefore, these data suggest that the primary microbial hazard factors for Sushi are S. aureus and B. cereus, in addition to V. parahaemolyticus, and further risk assessments should focus on those pathogens.

• Journal of Soil and Groundwater Environment
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• v.12 no.1
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• pp.64-72
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• 2007

Humans are exposed by a range of pollutants in soil via exposure routes such as ingestion, inhalation, and dermal contact. Risk assessment is a process of evaluating the adverse health effects of chemicals as a result of exposure to stressors, and it is a very useful tool to establish the cleanup goals in contaminated lands. In the exposure assessment that is one of main process in risk assessment, exposure factor plays a significant role to quantify the intake of soil pollutants. However there is a very limited study about the exposure factor applicable to Korea. In this study, we compared the exposure factors applied by the developed countries including the United States and representative European countries, and suggested the exposure factor that might be suitable in our situation. The exposure factors considered in this study include average lifetime, body weight, (exposed) skin surface area, life time, skin absorption, soil-skin adherence factor, and soil ingestion rate. This information is needed to quantitatively estimate the intake of soil pollutants in contaminated lands.

• Journal of Food Hygiene and Safety
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• v.25 no.2
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• pp.143-147
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• 2010

Chronic exposure to Arsenic (As) causes significant human health effects including various cancers. Total As concentrations from 300 polished rice samples cultivated near the mining areas in Korea were analyzed to estimate a probabilistic assessment of human health risk from As-contaminated rice. The mean of total As concentrations in rice was 0.09 mg/kg and lognormal distribution model was set for total As concentrations. Human health risk for As in rice was estimated using gender-specific rice consumption data and average daily dose (ADD). While cancer risk (CR) and hazard quotient (HQ) were calculated using oral cancer slope factor (OCSF) and Reference dose (RfD) suggested by the U.S. EPA. Mean of CR posed by total As was 2.16 (for male) and 1.83 (for female) per 10,000. The HQ for general population from rice cultivated near the mining areas in Korea was below 1 as the $50^{th}$ percentile of general population. However, less than 10% of general population consuming rice cultivated near the mining areas would exceed 1.0. This result is similar with those from each gender-specific group.