• Journal of Environmental Health Sciences
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• v.41 no.4
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• pp.268-276
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• 2015

Objectives: According to the 2007 Korea National Environmental Health Survey (KNEHS), some areas in the Gyeongsang Provinces showed very high blood mercury levels in adults. We conducted this project to investigate any related health effects in children due to mercury levels in these areas. Methods: In total, 1,097 students between grades 3 and 6 at 19 elementary schools were recruited from four areas with high mercury exposure as identified by the KNEHS. Total mercury levels in biological samples were compared with health check-ups performed on the schoolchildren. Biological monitoring, supported by questionnaires, a computerized neurobehavioral test, a posturography test and a personality test, were applied. Results: Triglycerides showed a significant relation with mercury in blood, urine and hair. Total mercury concentrations were divided into two groups: upper and lower concentration groups based on the median value. In the computerized neurobehavioral test, the upper blood mercury group showed a greater reaction time for color-word vigilance (p<0.05). In the posturography test, the intensity value of the tremor test showd high significant relations with mercury levels (p<0.01). In the personality test, self-consciousness, misdeeds and family relationships showed significant differences between the upper and lower urine mercury groups (p<0.01), and specific reactions, ego resilience and hyperactivity also showed some differences (p<0.1). Conclusion: Some items in the neurobehavioral test, posturography test and personality test showed significant relations with biological mercury levels. Therefore, monitoring and appropriate management of students showing high mercury levels are recommended in order to reduce their mercury exposure.

• Journal of Environmental Health Sciences
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• v.33 no.5
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• pp.345-352
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• 2007

As mercury absorbed into body can cross the blood-brain barrier and react with DNA and RNA. Central nervous system has been known to be affected especially in children. But it was very difficult to know the influences of chronic low-does Hg exposure on the health. Although many studies investigated the affect, most of results were still disparate. In order to investigate the health effects of mercury exposure, several test were conducted for some Korean school children. The general health effects were investigated using blood test, Posturography and computer-based neurobehavioral test was done to examine the affect of Hg into neural responses. About 400 children were chosen for blood test whose blood Hg level were upper and lower 10% of population participated in the nationwide Hg exposure survey. The concentration of calcium and creatine, the number of white and red blood cell showed statistical significance with Hg exposure in blood test. Another 36 children were selected from the same participants for the posturography and neurobehavioral test. The intensity and center frequency of hand tremor which were related to unconsciousness also showed distinct significances. Any general relations with Hg exposure were not found in all test including computer-based neurobehavioral test.

• Journal of Korean Elementary Science Education
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• v.21 no.2
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• pp.143-157
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• 2002

The aims of this study are to develop web-based learning materials for science and environmental education of elementary school. The effect of environmental education was divided into eight to measure: the awareness of using web as environmental material, the ability to use web as environmental material. the awareness of environmental problems, the satisfaction for environmental education using web, the awareness of preserving local environment, self-leading ability to learn environment, the effect of using environment homepage, and the internalization of environmental awareness. This study obtained the following results; First, as a result of post-test, the average of the test group of web-based learning was 1.29 points higher than the control group having traditional learning in the awareness of using web as environmental material, showing a statistically significant difference. Second, as a result of post-test, the average of the test group of web-based learning was 2.80 points higher than the control group in the ability to use web as environmental material, showing a statistically significant difference. Third, as a result of post-test, the average of the test group of web-based learning was 1.10 points higher than the control group in the awareness of environmental problems, showing a statistically significant difference. Fourth, as a result of post-test, the average of the test group of web-based teaming was 0.89 points higher than the control group in the satisfaction for environmental education using web, showing a statistically significant difference. Fifth, as a result of post-test, the average of the test group of web-based learning was 1.70 points higher than the control group in the self-leading ability to learn environment, showing a statistically significant difference. Sixth, as a result of post-test, the average of the test group of web-based learning was 1.21 points higher than the control group in the effect of using environment homepage, showing a statistically significant difference. Finally, as a result of post-test, the average of the test group of web-based learning was 1.39 points higher than the control group in the internalization of environmental awareness, showing a statistically significant difference. Based on these results, it is assumed that the teaching method which applied web-based teaming to science and environmental education in elementary school is a effective strategy for elementary science and on environmental education.

• Journal of Korean Society on Water Environment
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• v.31 no.1
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• pp.49-54
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• 2015

Acute toxicity test with Daphnia magna has a variety of factors such as incubation condition of test species, food quality and proficiency of laboratory workers. Therefore, proper proficiency testing samples were required for evaluating the competence of laboratory workers. This study aims to propose some appropriate proficiency testing samples for laboratory workers of acute toxicity test with Daphnia magna. Proposed four kinds of standard samples (Sample A, B, C, and D) for proficiency testing were selected from reference materials which were recommended from Canada and USA WET(Whole Effluent Toxicity) authorities. Proposed standard samples were tested by trial application of proficiency testing, homogeneity and stability checks using repeatability test. Sample A, C and D were estimated ad the suitable candidates for proficiency test standard samples except for Sample B. In addition, Sample A was proved to be the most suitable sample.

• Environmental Analysis Health and Toxicology
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• v.30 no.sup
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• pp.4.1-4.7
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• 2015

Objectives Approximately 2000 phase-in substances are subject to registration according to the Act on the Registration and Evaluation, etc. of Chemical Substances (K-REACH), and the expected testing cost is 2.06 trillion Korean won assuming all the test data required for registration are acquired. The extent to which these enormous test costs can be reduced depends on the availability of existing data that can be used to meet the requirements of the K-REACH we examined the current availability of test data that can be used for chemical substance registration. Methods We analyzed the possibility of utilizing the existing test data obtained from 16 reference databases for 369 of 518 kinds of phase-in substances subject to registration that were reported in last October 2014. Results The physical and chemical properties were available for 57.1% of substances, whereas data regarding human hazards and environmental hazards were available at considerably lower rates, 8.5% and 11.8%, respectively. Conclusions Physical and chemical properties were available for a fairly high proportion, whereas human hazards and environmental hazards were reported for considerably fewer substances.

• Journal of Environmental Science International
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• v.16 no.4
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• pp.425-432
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• 2007

The water flea has been used as a test organism of toxicity test for surface water. Toxicity test with water flea is categorized into two parts. One is acute toxicity test with observing immobility and mortality and the other is chronic toxicity test determined by survival and reproduction of water flea. Heartbeat measurement of water flea was designed as a short-term toxicity test in this study. Direct measurement of heartbeat under microscope by aid of video camera gives and early diagnosis of mortality in short time. Therefore, the effects of measuring illumination, measuring time, and non-feeding during the test on heartbeat of water flea was evaluated to establish a new test approach. Test organisms used in this study are Daphnia magna, a well standardizes toxicity test organism, and Simocephalus mixtus, a newly refined organism $IC_{50}$ values of these test organism by heartbeat measurement were compared and discussed. It was found that toxicity test by heartbeat measurement was a reproducible, easy and simple method accomplished in a few hours.

• Environmental Analysis Health and Toxicology
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• v.14 no.4
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• pp.135-144
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• 1999

Environmental toxicities of priority water pollutants were evaluated by two selected bioassays, Lettuce seed germination/elongation test and Microtox acute toxicity test. Toxic chemicals (heavy metals, polycyclic aromatic hydrocarbons, and phenolic compounds) inhibited the germination rate and root elongation of Lettuce seed, as well as the bioluminescence of Microtox bacteria. When test biota were exposed to target chemicals, the sensitivity of Lettuce bioassay was relatively lower than that of Microtox bioassay. However, Lettuce bioassay may be a good candidate for prescreening the environmental toxicities of priority water pollutants, since the testing method with Lettuce seed was relatively easier and more economic than with Microtox bacteria. Toxicity tests were conducted to compare the validity and sensitivity of both bioassays for sediment from a small stream passed through urban area as well as leachate from a municipal solid waste landfill. From experimental results, we found that Lettuce test and Microtox test are compensated each other as a battery of bioassay for evaluating the environmental toxicities of field samples obtained from a small stream contaminated by pollutants.

• Hwankyungkyoyuk
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• v.13 no.1
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• pp.44-52
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• 2000

In this study, the effects of structured controversy strategy, individual learning, and traditional learning on the learning of environmental unit in ‘General Science’ were compared. One hundred and forty-three 10th-graders had been taught about environmental issues-self purification, biological concentration, acid rain, greenhouse effect, noise, and radioactivity-for 6 class hours. Prior to the instructions, environmental attitudes test and self-esteem test were administered. After the instructions, their achievements, critical thinking, environmental attitudes. self-esteem, and views on Science-Technology-Society were examined. The results of 2-way ANCOVA and/or Kruskal-Wallis test revealed that there were no significant main effects in the scores of the achievement test and the critical thinking test. The environmental attitudes test scores tended to be highest in the structured controversy group, and lowest in the traditional learning group. Self-esteem scores of the structured controversy group and the individual learning group were higher than those of the traditional learning group. Significant differences by students' prior achievement level in students' critical thinking, environmental attitudes, and views on Science-Technology-Society were also found.

• Journal of Korean Society for Quality Management
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• v.46 no.2
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• pp.311-326
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• 2018

Purpose: Using international specifications, this study classified international standards and automobile manufacturers' test items based on the kind of test used and determined the test order for ISO 16750. Methods: The effects of international standards' environmental factors were examined, based on the major impacts of the product and the results of product failure. Automobile manufacturers' test items were compared with the test item in the ISO 16750. A generic algorithm was then used to determine the test sequence for ISO 16750. Results: International standards and automobile manufacturers' common test items were classified. The test sequence of ISO 16750 was determined for five cases. Conclusion: Although mechanical and environmental tests share many common features, there are differences in the details of the tests. There is a common sequence of tests, but weights are allocated tests differently.

• Journal of Applied Reliability
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• v.16 no.4
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• pp.287-294
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• 2016

Purpose: Environment test support is urgent for small and medium defense companies in order to improve the reliability of weapons systems. Also, to reduce the burden of test costs, the voucher system must be strengthened. Quality assurance support should be accompanied by budget support. Methods: First of all, it is necessary to expand infrastructure for test equipment that suffers shortages by considering environmental test frequency and waiting periods to reduce the time required for environmental tests. Results: In regard to the environmental test, expansion for test equipment infrastructure, security of budget for the test, establishment of test plan, education and consulting support are required to resolve some limits of small and medium defense companies. Conclusion: Along with the opening of environmental test courses for industry operators, the expansion for consulting support projects of the defense industry support system is needed.