• Toxicological Research
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• v.18 no.1
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• pp.1-11
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• 2002

3-Monochloro-1,2-propanediol(3-MCPD) is currently being a matter of concern because of its toxicity. 3-MCPD produced during the acid hydrolysis of soybean products has been reported to be mutagenic, neurotoxic, nephrotoxic and spermatotoxic. Howerer, the carcinogenicity of 3-MCPD is a controversial issue over the past several decades. 3-MCPD characteristically showed a variety of toxicities in reproductive system such as, decrease in sperm number and sperm motility, infertility, loss of sperm function, and weight decrease in ovary. Due to the toxicity of 3-MCPD, exposure to 3-MCPD has been proposed to be reduced to as low a level as technologically feasible. 3-MCPD can be detected in soy sauce or non-soy sauce products. The legal limit for 3-MCPD this year has been suggested to be 20 ppb（$\mu\textrm{g}$/kg）in the European Community. In Korea, the permissible level of 3-MCPD is expected to be 0.3 ppm. In this study, 3-MCPD was toxicologically evaluated in terms of risk assessment in humans.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2004.10a
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• pp.517-526
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• 2004

In the resent years, the early evaluation of concrete quality, construction and maintenance has been considered as all is of major concern due to the increase of loading and the degradation of structures related with time. This paper presents evaluation of structural safety performance using measured data of construction, on the basis of a field measurements for the prevention of unreliable concrete works. Measurements analyzed in this paper are early quality condition and performance assessment, serviceability performance by cracks and deflection, rating performance by loading, durability performance by chloride attack and carbonation. Thus, a quantitative assessment model of resistance capacity was developed here to meet the requirement for deteriorated concrete structures. The model focuses on damage mechanical of concrete structures deteriorated by initial damage factors for concrete quality and environment factors such as chloride and carbonation attacks. These results could provide useful information for concrete structures interested in design, construction and maintenance.

• Journal of Environmental Health Sciences
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• v.37 no.1
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• pp.73-79
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• 2011

The growing interest in nanotechnology has resulted in increasing concern and a number of published environmental and workplace measurements for assessing occupational exposure to engineered nanomaterials. However, the amount of previous exposure data remains limited. Furthermore the data available was collected with extensive variation in terms of exposure measurement strategy, which limits the ability to pool the data in the future. In response, this paper reviewed several pertinent issues related to exposure measurement strategy to suggest a harmonized measurement strategy which would make exposure data more useful in the future, e.g. correlation between exposure metrics, relationship between activity and exposure, task-based or shift-based assessment, background concentration, limitation of personal exposure monitoring and other determinants of exposure/modeling. An improved sampling strategy for nanomaterial exposure assessment should be considered in order to maximize the use of the data from various real time monitoring instruments.

• Special Issue of the Society of Naval Architects of Korea
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• 2008.09a
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• pp.76-83
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• 2008

New and more efficient propulsion systems are required for LNG carriers. One of the proposed systems is a combination of a gas turbine with a heat recovery steam generator. This system constitutes a novel approach, which needs to be analyzed by system analysis and risk assessment to compensate for the lack of field experience. Of specific concern is the high pressure fuel supply system. This paper describes the dispersion and fire analysis performed to identify for safety and design improvement of proposed system.

• Journal of Environmental Health Sciences
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• v.44 no.6
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• pp.548-555
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• 2018

Objectives: We conducted ecological risk assessment for cadmium, a heavy metal and carcinogen, to identify safety standards by environmental media and to determine its impact on ecosystems by estimating and evaluating exposure levels. Methods: Species sensitivity distributions (SSDs) were generated using ECOTOX DB. A hazardous concentration of 5% (HC5) protective of most species (95%) in the environment was estimated. Using this estimate, predicted no effect concentrations (PNECs) were calculated for aquatic organisms. Based on the calculated PNECs for aquatic organisms, PNEC values for soil and sediment were calculated using the partition coefficient. Predicted exposure concentrations (PECs) were also calculated from environmental monitoring data with hazard quotients (HQs) calculated using PNECs for environmental media. Results: Chronic toxicity data were categorized into four groups and 11 species. In species sensitivity distribution (SSD) analysis, HC5 was $0.340{\mu}g/L$. Based on this value, the PNEC value for aquatic organisms was calculated as $0.113{\mu}g/L$. PNEC values for soil and sediments using a partition coefficient were calculated as 15.02 mg/kg and 90.61 mg/kg, respectively. In an analysis of environmental monitoring data, PEC values were calculated as $0.017{\mu}g/L$ for water, 1.01 mg/kg for soil, and 0.521 mg/kg for sediment. Conclusions: HQs were 0.150, 0.067 and 0.006 for water, soil and sediment, respectively. HQs of secondary toxicity were 0.365 for birds and 0.024 for mammals. In principle, it is judged that an HQ above 1 indicates a high level of risk concern while an HQ less than 1 indicates an extremely low level of risk concern. Therefore, with HQs of cadmium in the environment being <1, its risk levels can be considered low for each media.

• Communications of Mathematical Education
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• v.22 no.2
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• pp.229-252
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• 2008

The purpose of this research was to make fair assessment methods which took into account characteristics of mathematically underachievers. The researchers devised an descriptive tests and interviews and applied them to the mathematics underachievers who could not reveal their achievements in the traditional assessment and then analyzed their cognitive and affective characteristics in the alternative assessments. After selecting three students by the normal assessment made of simple subjective and multiple choice questions, the cognitive and affective characteristics found in the general assessment were reflected to the descriptive tests and interviews. The descriptive tests and interviews are comprised of descriptive narrations and informal interview questions. After the assessment, the teacher and students gave feedbacks one another. All the assessment activities were recorded by a camcorder to analyze cognitive and affective characteristics of the children. Throughout the research, the following conclusions were made. The mathematics underachievers showed the characteristics which didn't appeared in the normal assessment. They showed normal abilities of problem solving and communication In the cognitive area. Also they brought in positive result in most parts in the affective area. However, the student B displayed considerable ability of mathematical thinking that is over the average level of mathematical underachievers. This implies that we can definite the mathematical underachievers differently when we use the detailed and relief assessment method instead of the traditional assessment. On the other hand, one student tended to depend on the teacher and another student overheard what the others talk during the study. This defect should be complemented by the further studies about assessment method for the mathematical underachievers. Also appropriate assessment methods should be made for applying to the various mathematical underachievers. Many studies have been concentrated on the learning for mathematical underachievers but there is little concern about the assessment for the mathematical underachievers. However it is the fundamental way to reduce the number of mathematics underachievers that we construct consistent learning methods and assessments for the mathematical underachievers.

• Hwankyungkyoyuk
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• v.18 no.2 s.27
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• pp.31-43
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• 2005

In this study, after establishing assessment framework and reviewing the conceptual evolution and component of EL(Environmental Literacy) through literature review, through middle school students as population, the level of EL and relationship of its related variables were examined. The investigation was consisted of second and third grades of urban and rural middle schools in Choongbook. The used measurement methods were objective evaluation and Likert-type scale. The questionnaire instrument variables were consisted of 80 items on environmental literacy variables and six items on student gender, area of residence, environmental lesson, degree of environmental concern, environmental information, environmental activity as background variables. The major findings of this study were as follows: 1. Although the broad and obscure concept of EL has been evolved until 1992, it has been developed more systematic and precise after 1992. But there is not still an agreed concept. 2. The subordinate components of EL were consisted of cognitive, affective, and behavioral aspects. Both ecological knowledge(KEOC) and environmental skill(SKILL) were determined to serve as two powerful predictors of EL. 3. The level of EL of middle school student was showed statistically significant difference to some variables by student gender, residential area, environmental lesson, environmental concern, environmental information, and environmental activity variables. And the most influential variables of EL in middle school student were environmental skill(SKILL), and locus of control (LOC). Based on the findings of this study, the following suggestions are drawn: It should be established a precise concept on EL as the ultimate aim of environmental education both interdisciplinary cooperation and experts of environmental education and also performed further longitudinal study which assessed multidimensional variables which are able to exactly measure the EL of middle school student.

• Journal of Nutrition and Health
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• v.37 no.4
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• pp.310-315
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• 2004

The purposes of this study were to: a) develop the quality assessment tool of Web-based Instruction (WBI) for nutrition education, b) evaluate the operated WBI (NutriZone) by this tool, and c) do the feasibility study about quality assessment tool for WBI by establishing the instruction and operating strategies. The developed quality assessment tool of WBI for nutrition education was divided into three categories of instruction design, contents and support ＆ operation. And a total of forty items were measured by Likert 5 point scale, computed as one point per item, and amounted to forty points in all. As a result of evaluation, NutriZone got 21.79 out of 40 points and fulfillment rate of 54.5%. The IPA (Importance-Performance Analysis) was applied to establish the instruction and operating strategies, and nine items characterized as attractiveness, multimedia, and learner-initiative were in 'Doing Great, Keep It Up', and so it was regar-ded as program designed with concern in WBI's characteristics unlike the conventional face-to-face education. But twelve items such as 'Errors on switch to other screens are few.', 'Ready correction leads to be out of systemic error.', 'Highlight marks and moving pictures were used in sign of importance.' and etc. that got high importance and low performance needed to be focused in instructional strategy.

• Journal of Environmental Impact Assessment
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• v.18 no.6
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• pp.387-392
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• 2009

As Our society's environmental awareness and concern the significant increases, the importance of the legal system for environmental conservation such as the Prior Environmental Review System, Environmental Impact Assessment is growing increasingly. but, still critical issues are present such as reliability. Though there could be various causes such as the system or procedures etc. Above all, basically the environmental data problem is the critical cause. Therefore, this study was trying to improve the environmental data accuracy using the high-resolution color aerial photography, LiDAR data and Object Oriented Classification method. And in this study, classification based on coverage percentage of a particular species was attempted through the multi-resolution segmentation and multi-level classification method. The classification result was verified by comparison with 11 points local survey data. All 11 points were classified correctly. And even though the exact coverage percentage of the particular species did not be measured, It was confirmed that the species was occupied similar portion. It is important that the environmental data which can be used for the conservation value assessment could be acquired.

• Nuclear Engineering and Technology
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• v.50 no.3
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• pp.319-326
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• 2018

Since the Fukushima Daiichi nuclear disaster, concern and worry about multiunit accidents have been increasing. Korea has a higher urgency to evaluate its site risk because its number of nuclear power plants (NPPs) and population density are higher than those in other countries. Since the 1980s, technical documents have been published on multiunit probabilistic safety assessment (PSA), but the Fukushima accident accelerated research on multiunit PSA. It is therefore necessary to summarize the present situation and draw implications for further research. This article reviews journal and conference papers on multiunit or site risk evaluation published between 2011 and 2016. The contents of the reviewed literature are classified as research status, initiators, and methodologies representing dependencies, and the insights and conclusions are consolidated. As of 2017, the regulatory authority and nuclear power utility have launched a full-scale project to assess multiunit risk in Korea. This article provides comprehensive reference materials on the necessary enabling technology for subsequent studies of multiunit or site risk assessment.