• Fire Science and Engineering
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• v.14 no.4
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• pp.7-16
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• 2000

In the study, three criteria(toxicity, fire & explosion, environment) and damage prediction method for each case was set up, and all these criteria were applied to the subject substance that was selected as hazardous level by integrating all criteria through Algorithm. Particularly, the environment criterion is a comprehensive concept, environment index modeling by combining USCG(United State Coast Guard) & MSDS(Material Safety Data Sheet) environment criteria classifications and the environment part of MFPA's health hazardousnes(Nh). And for damage prediction method of each criterion were adopted and they were applied to hazardous chemical substances in use or stored by chemical substance related enterprises located in each region that made possible to set up total hazard level of used substances(inflammability, poisonousness and counteraction on a unit substance, and hazard level & display modeling on environment) & damage prediction in case of accident & solidity setup(CPQRA: Chemical Process Quantitative Risk Assessment, IAEA: International Atomic Energy Agency, VZ eq: Vulnerable Zone) risk counter. Thus it is deemed that it can be applied to toxic substance leakage that can happen during any chemical processing & storage, application as a tool for prior safety evaluation through potential dangerousness computation of fire & explosion.

• Applied Chemistry for Engineering
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• v.28 no.1
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• pp.35-41
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• 2017

Materials exposed to outside will deteriorate due to various weathering factors such as sunlight, heat, temperature, humidity and so on. Therefore, predicting speed of degradation and life time is a very important issue. This research uses retro-reflective sheets with white and green which are most commonly used colors to conduct the outdoor exposure test and acceleration test of xenon arc in Arizona state in the United States, Chennai in India, Sanary in France and Seosan in Korea to measure the reflective performance of retro-reflection. The accelerated factor was obtained by using regression analysis through reflective values obtained from the acceleration test of xenon arc from Seosan area. Also, by using solar uv program, the accelerated factor of various climate regions were obtained and it was confirmed that the accelerated factor of Senary was 1.04, Arizona 1.82, Chennai 1.92 times higher than that of Seosan.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2003.05a
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• pp.139-142
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• 2003

Traditionally, the thickness of fire protection materials of structural elements such as beam and column have been decided by fire test using the predominant steel section of $H-300{\times}300{\times}10{\times}15$ for column and $H-400{\times}200{\times}8{\times}13$ for beam in Korea. But this way of determination of fire protection thickness yields very unduly results. Because the temperature-increment rate of structural steel elements depends mainly on magnitude of their cross-areas. In general, the thicker size of cross-areas for structural elements, the lower temperature shows up. It had already proved that the fire protection thickness only depends on the size of cross-areas and the fire protection method for three-fide or four-side exposed conditions in European countries, the United State of America and so on. To demonstrate there would be differences among various cross-areas for structural elements, we conducted several fire tests with full-scale specimens of beams and columns. For the determination of critical temperature for steel section when the fire resistant performance is needed to be decided, we conducted with a loaded fire test for beam and column, respectively. The small column in 1.0 meter length and beam in 1.5 meter length were used in order to deprive the rational fire protection thickness of structural elements such as beam and column, respectively. After test, we could obtain there were significant temperature lass between higher cross-areas and lower cross-areas. The critical temperature of steel as a criterion is used 538$^{\circ}C$ for column and 593$^{\circ}C$ for beam which is from ASTM E 119 because we don't make provisions as critical temperature by elements. We could consider that the best way of determination of fire protection thickness is using the following multi-regression equation which was deprived from several fire tests using the concept of section factor, FR(column) = 0.17 +5191.49t A/Hp + 40.77t, FR(beam) = 0.25 +6899.31t A/Hp + 32.60t(where, FR means fire resistant time, t means thickness, A means cross-area and Hp means heated parameter).

• 수도
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• v.24 no.5 s.86
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• pp.29-44
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• 1997

Sewage sludge produced in Korea was 1,275,800 tons (dewatered sludge cake) per year in 1996, which is 3,495 tons per day, 0.303% of 11,526,100 tons per day of sewage treated in 79 sewage treatment plants. Sludge production has been and will be increasing in accordance with construction of new facilities for sewage treatment. Most of the sludge is currently disposed by landfill and ocean dumping, but it is becoming difficult to find suitable sites for landfill, particularly in big cities such as Seoul. In addition, rapid increase of landfill cost is anticipated in a near future. Current trend for sludge disposal in advanced countries is land application. Over the past 10 to 20 years in the United States, sludge management practices have changed significantly, moving from disposal to beneficial use. They use biosolid for utilization instead of sludge for disposal. Under the Clean Water Act of 1972, amended in 1987 by Congress, the U.S. EPA was required to develop regulations for the use and disposal of sewage sludge. The EPA assessed the potential for pollutants in sewage sludge to affect public health and the environment through a number of different routes of exposure. The Agency also assessed the potential risk to human health through contamination of drinking water sources or surface water when sludge is disposed on land. The Final Rules were signed by the EPA Administrator and were published (Federal Register, 1993). These rules state that sewage sludge shall not be applied to land if the concentration of any pollutant in the sludge exceeds the ceiling concentration. In addition, the cumulative loading rate for each pollutant shall not exceed the cumulative pollutant loading rate nor should the concentration of each pollutant in the sludge exceed the monthly average concentration for the pollutant. The annual pollutant loading rate generally applies to applications of sewage sludge on agricultural lands. The most popular beneficial use of sewage sludge is land application. The sludge has to be stabilized for appling to land. One of the stabilization process for sewage sludge is lime stabilization process. The stabilization process is consisted of the stabilizing process and the drying process. Stabilization reactor can be a drum type reactor in which a crossed mixer is equipped. The additive agents are a very reactive mixture of calcium oxide and others. The stabilized sludge is dried in sun drier or rotary kiln.

• Journal of Korean Library and Information Science Society
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• v.51 no.3
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• pp.1-25
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• 2020

The World Health Organization estimated that more than a billion people (or 15% of the world's population) lives with disabilities. They have the same information needs as non-disabled people. Nevertheless, as the World Blind Union estimated, less than 10% of published books are ever made into accessible formats in developed countries. The role of the national library should be very important to improve the information accessibility for the disabled. Based on this perspective, this study analyzed and compared the history and development, legal basis and organization, main functions and tasks, and service features for the disabled for the Library of Congress of the United States, MTM(Myndigheten för Tillgängliga Medier) of Sweden, National Diet Library of Japan, and SALB (South African Library for the Blind) of Republic of South Africa representing the nationwide disability services by continent. And based on the results of the analysis, this study suggested ways to strengthen the capacity of the National Library for the Disabled of Korea.

• Journal of Microbiology and Biotechnology
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• v.21 no.9
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• pp.954-959
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• 2011

There have been a number of studies conducted in order to compare the efficiencies of recovery rates, utilizing different protocols, for the isolation of L. monocytogenes. However, the severity of multiple cell injury has not been included in these studies. In the current study, L. monocytogenes ATCC 19112 was injured by exposure to extreme temperatures ($60^{\circ}C$ and $-20^{\circ}C$) for a one-step injury, and for a two-step injury the cells were transferred directly from a heat treatment to frozen state to induce a severe cell injury (up to 100% injury). The injured cells were then subjected to the US Food and Drug Administration (FDA), the ISO-11290, and the modified United States Department of Agriculture (mUSDA) protocols, and plated on TSAyeast (0.6% yeast), PALCAM agar, and CHROMAgar Listeria for 24 h or 48 h. The evaluation of the total recovery of injured cells was also calculated based on the costs involved in the preparation of media for each protocol. Results indicate that the mUSDA method is best able to aid the recovery of heat-injured, freeze-injured, and heat-freeze-injured cells and was shown to be the most cost effective for heat-freeze-injured cells.

• Journal of Radiation Protection and Research
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• v.41 no.4
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• pp.424-435
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• 2016

Background: The International Commission on Radiological Protection (ICRP) recommendations and the Federal Guidance Report (FGR) published by the U.S. Environmental Protection Agency (EPA) have been widely applied worldwide in the fields of radiation protection and dose assessment. The dose conversion coefficients of the ICRP and FGR are widely used for assessing exposure doses. However, before the coefficients are used, the user must thoroughly understand the derivation process of the coefficients to ensure that they are used appropriately in the evaluation. Materials and Methods: The ICRP provides recommendations to regulatory and advisory agencies, mainly in the form of guidance on the fundamental principles on which appropriate radiological protection can be based. The FGR provides federal and state agencies with technical information to assist their implementation of radiation protection programs for the U.S. population. The system of radiation dose assessment and dose conversion coefficients in the ICRP and FGR is reviewed in this study. Results and Discussion: A thorough understanding of their background is essential for the proper use of dose conversion coefficients. The FGR dose assessment system was strongly influenced by the ICRP and the U.S. National Council on Radiation Protection and Measurements (NCRP), and is hence consistent with those recommendations. Moreover, the ICRP and FGR both used the scientific data reported by Biological Effects of Ionizing Radiation (BEIR) and United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) as their primary source of information. The difference between the ICRP and FGR lies in the fact that the ICRP utilized information regarding a population of diverse races, whereas the FGR utilized data on the American population, as its goal was to provide guidelines for radiological protection in the US. Conclusion: The contents of this study are expected to be utilized as basic research material in the areas of radiation protection and dose assessment.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.30 no.1
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• pp.123-139
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• 2020

In 1987, Computer Security Act was enacted, requiring computer security awareness and practical training for federal workforce. This is the beginning of US development of federal cybersecurity workforce. It has been strengthening the development of federal cybersecurity workforce policy by establishing OPM regulations and OMB circulation in cases where it is difficult to define by law. Through GISRA 2000 and FISMA 2002, which has been improved, it played a central role for development of federal cybersecurity workforce for more than 10 years. Since then, FISMA 2014 has been enacted as a necessity for supplementing technology and policy. In 2014, the importance of cyber security personnel in US federal agencies has been increased even more, by enacting a single law on cybersecurity workforce twice. We will review the current state of Korea's development of cybersecurity workforce by reviewing and analyzing the development and federal cybersecurity workforce in the United States.

• Journal of Environmental Health Sciences
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• v.40 no.5
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• pp.397-406
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• 2014

Objectives: Perchloroethylene (PCE) is a volatile chemical widely used as a solvent in the dry-cleaning and textile processing industries. It was evaluated as Group 2 "probably carcinogenic to humans" by the Integrated Risk Information System (IRIS) of the United State Environmental Protection Agency (U.S. EPA) in 2012. In order to provide a scientific basis for establishing risk management measures for chemicals on the national priority substances list, aggregate risk assessment was conducted for PCE, included in the top-10 substances. Methods: We conducted the investigation and monitoring of PCE exposure (e.g., exposure scenario, detection levels, and exposure factors, etc.) and assessed its multi-media (e.g., outdoor air, indoor air, and ground water) exposure risk with a deterministic and probabilistic approach. Results: In human risk assessment (HRA), the level of human exposure was higher in the younger age group. The exposure level through inhalation at home was the highest among the exposure routes. Outdoor air or uptake of drinking water represented less than 1% of total contributions to PCE exposure. These findings suggested that the level of risk was negligible since the Hazard Index (HI) induced by HRA was below one among all age groups, with a maximum HI value of 0.17 when reasonable maximum exposure was applied. Conclusion: In conclusion, it was suggested that despite low exposure risk, further studies are needed considering main sources, including occupational exposure.

• Korean Journal of Agricultural Science
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• v.44 no.1
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• pp.123-132
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• 2017

Nowadays, many people suffer from stress because of their jobs, studies, traffic, etc. Daily stress may cause many diseases (Garrett, 1991). One of the methods for reducing stress is experiencing a natural environment (Frumkin, 2001). Cibodas botanical garden (CBG) is one of the most famous travel destinations in Bogor, Indonesia. CBG has the potential for tourism activities. However, an economic assessment is required to verify their sustainability. The research objectives of this study were to identify the characteristics of tourism utilization in CBG, to analyze the economic tourism value of CBG, and to measure the effectiveness of traveling to a natural environment for reducing stress. The research method used was the survey. This study used three data analysis methods: (1) descriptive analysis which was used to identify the characteristics of tourists, (2) travel cost method (TCM), and (3) contingent valuation method (CVM). Results showed some differences in the characteristics of foreign and domestic tourists respondents in age, educational background, income level, number of dependents, and the frequency of their visits. CBG has a high economic value, amounting to IDR (Indonesian Rupiah) 5,508,932,605,405 or approximately USD (United State Dollar) 413,000,000. WTP (Willingness to Pay) of domestic tourist respondents was IDR 29,702 or USD 2.2 per visit, while the value of foreign tourist respondents reached IDR 39,700 or USD 2.9 per visit. Respondents found it preferable to pay more for tickets (WTP value) than to buy medication to reduce their stress.