• Horticultural Science & Technology
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• v.19 no.4
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• pp.568-573
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• 2001

The effects of foliar spray and soil drench application of triazole chemicals (diniconazole, myclobutanil, difenoconazole, tebuconazole, bitertanol, hexaconazole) on growth and flowering control in zinnia were investigated. For foliar spray application of tebuconazole, diniconazole and bitertanol on 'Dream Land Rose', plant height was decreased but tebuconazole gave the best result for dwarfing. Diameter, fresh and dry weights of flower were markably decreased at high concentration of tebuconazole. However, days to flowering was not affected by chemicals tested. For 'Dream Land Scarlet', plant height was decreased with all chemical treatments. Tebuconazole severely decreased plant height, in particulas. Diniconazole hastened flowering. For soil drench of 'Dream Land Rose', plant height was decreased by diniconazole and mycrobutanil, but diniconazole was more effective for plant height decrease. Flowering was hastened by diniconazole in both 'Dream Land Rose' and 'Dream Land Scarlet'. Plant height of 'Dream Land Scarlet' was decreased by all chemicals tested. Flowering was not occurred at $300mg{\cdot}L^{-1}$ myclobutanil with severe suppression of stem growth.

• Parasites, Hosts and Diseases
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• v.54 no.1
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• pp.97-101
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• 2016

Lyme disease is a tick-borne zoonotic infectious disease caused by Borrelia burgdorferi. The present study assessed the infection status of B. burgdorferi among horses reared in Korea using ELISA and PCR. Between 2009 and 2013, blood samples were collected from 727 horses throughout Korea. Data for each animal including age, gender, breed, and region of sample collection were used for epidemiological analysis. Overall, 38 (5.2%; true prevalence: 5.5%) of 727 horses were seropositive by ELISA. There were statistically significant differences according to breed and region (P<0.001) whose differences might be attributed to the ecology of vector ticks and climate conditions. Using 2 nested PCR, none of the samples tested positive for B. burgdorferi. Thus, a positive ELISA result can indicate only that the tested horse was previously exposed to B. burgdorferi, with no certainty over the time of exposure. Since global warming is likely to increase the abundance of ticks in Korea, continuous monitoring of tick-borne diseases in Korean horses is needed.

• The Korean Journal of Elementary Counseling
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• v.10 no.2
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• pp.223-236
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• 2011

The purpose of this study is to administer the career education program connected to families of the fourth graders and to test if it would have significant impacts on their career awareness. The sixty students(30 for test, 30 for regulation) from two the fourth grade classes at S elementary school in Daejeon city were the objects of this study. After testing the test and the regulation group in advance, the career education program connected with the families was done to the test group. To find out that if career awareness of tested group students who participated in career education program connected with the families was improved than regulated group students', the grades of the advanced and afterward test were put as same condition and operated ANCOVA which compares to the scores of tested group and regulated group. The result of the study is as follows. First, the career education program connected with the families has affirmative effects on developing career awareness of elementary school students. Second, career education program connected with the families has affirmative effects on self-understanding, recognition of occupation and an attitude for career, which are low ranks of career awareness.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.11
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• pp.5025-5032
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• 2012

The purpose of this study is to compare the working memory and the phonological awareness between Children with multi-cultural families and general families. The research subjects were 15 multi-cultural and 15 general primary school students who were attending 1st-3rd grade in D city. Working memory tested K-TTFC-2 by standardized tool. Phonological awareness abilities was considering the age of the subjects, tested phoneme awareness. Data process was conducted by t -test and frequency test in SPSS program. The results were as follows. First, working memory comparison of both groups showed significant differences. Especially had significant difference in chapter 1, chapter 4. Second, comparison of phonological awareness between both groups showed significant statistic differences. Third, the Phonological awareness comparison of both groups showed that there are differences in sound matching(word medial coda), substituting middle sound in monosyllabic words, phoneme switching. This research result is considered that can be used as the fundamental data for the development of the therapy data considering the working memory and the phonological awareness of children with multi-cultural families.

• Applied Chemistry for Engineering
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• v.10 no.7
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• pp.1066-1072
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• 1999

The physical properties of polymer concrete were investigated for development of high-performance construction materials. Various specimens of polymer concrete were prepared using unsaturated polyester resin as the polymer-binder with the various dosage of calcium carbonate as microfiller (5~20 wt %) and fine aggregate(10~50 wt %). For the evaluation of the physical properties of polymer concretes, tests such as compressive strength, flexural strength, water absorption test, hot water immersion test, acid resistance test and pore size distribution analysis were conducted. As a result, it is concluded that compressive and flexural strengths of polymer concretes increased up to 4 times than those of conventional cement concrete. Whereas the compressive and flexural strengths of polymer concretes tested after hot water immersion, compared with those of polymer concretes tested before hot water immersion, decreased about 67%, 47%, respectively. By hot water immersion, total pore volume and porosity(%) of polymer concretes were remarkable increased due to decomposition of polymer binder. And also, it is showed that water absorption(%) and weight loss(%) of polymer concrete specimens by acid immersion, compared with those of ordinary portland cement concrete, decreased about 1/100, 1/27, respectively.

• Journal of Korean Society on Water Environment
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• v.16 no.4
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• pp.469-477
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• 2000

Bisphenol-A (BPA), a known endocrine disruptor, is a main building block of epoxy resin which is widely used as a coating agent in residential water storage tanks. Therefore, BPA leaching from the epoxy resin may have adverse effects on human health. The possibility of BPA leaching from three epoxy resins were tested with a modified KS D 8502 method at 20, 50, 75 and $100^{\circ}C$ in deionized water and the specified test water, respectively. BPA leached to the test water was identified using GC-MS and quantified with GC-FID after a sequential extraction and concentration. The results showed that BPA leaching has occurred in all three samples tested. The quantify of BPA leaching from unit area of epoxy resin coating was in the range of $10.677{\sim}273.120{\mu}g/m^2$ for sample A, 29.737~1734.045 for sample B and 52.857~548.778 for sample C depending on the test temperature, respectively. In general, the amount of BPA leaching increased as the water temperature increases. This result implies a higher risk of BPA leaching to drinking water during a hot summer season. In addition, microbial growth, measured by colony forming units, in epoxy coated water tanks was higher than that in a stainless steel tank suggesting that compounds leaching from epoxy resin may support the growth of microorganisms in a residential water holding tank.

• Proceedings of the KSME Conference
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• 2001.06e
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• pp.772-776
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• 2001

The flow structures of turbulent shear layer behind oil fences with different tip configurations were investigated experimentally using flow visualization and PIV velocity field measurement. An oil fence was installed in a circulating water channel and the flow structure around the fence tip was mainly analyzed in this experiment. The four tip configurations tested in this experiment are knife edge; semi-circle edge, circular edge and rectangular edge. The 300 instantaneous velocity fields were measured using the single-frame PIV system and they were ensemble averaged to give the mean velocity field and spatial distribution of turbulent statistics. Free stream velocity was fixed at 10ms/sec and the corresponding Reynolds number based on the fence height was Re=4000. As a result, for the oil fence with rectangular edge, the streamwise velocity component was decreased. On the other hand it was increased for the oil fence with circular edge. For all four fences tested in this study, general flow pattern of the lower shear layer is analogous but the upper layer shows difference depending on the tip configurations. The oil fence with circular edge has more diffusive upper shear layer than that of the others. The shear layer of the oil fence with rectangular edge has relatively thin thickness. The oil fence with circular edge was found to be proper shape for tandem fence.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.5
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• pp.1237-1245
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• 1993

In this study, a model of a flat plate solar collector using a heat pipe was manufactured and tested to investigate such operational characteristics of the present system of solar collector as start-up process, temperature distribution on the absorber plate and operation of the heat pipe. Moreover, collector efficiency was measured for 20-30 minutes of operation at various conditions of weather and the result was compared with that tested by Hill et. a. for a flat plate solar collector using direct circulation of coolant. Some results obtained in this study could be summarized as follows. (1) The required time for the initial start-up process was about 5-6 minutes, but the heat pipe began to operate as soon as the absorber plate was exposed to solar radiation. (2) On the absorber plate, the temperature distributions in axial direction maintained nearly constant, while temperature distributions in transversal direction showed smooth decrease with $3-5^{\cird}C$ along with solar radiation. (3) Thermal inertia of the collector system had a favorable effect to damp the turbulent variation of solar radiation. (4) The collector efficiency of the present system showed nearly the same tendency but a decrease of about 10% compared with that using direct circulation of coolant.

• Environmental Analysis Health and Toxicology
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• v.18 no.2
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• pp.101-109
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• 2003

Humans are exposed to toxic element arsenic (As) from air, food and water The current study was performed to investigate the levels of arsenic in the internal organs (liver, kidney cortex, lung, cerebrum. abdominal muscle and abdominal skin) and to find out correlation with age and interrelationship between tissues in Korean human bodies who had lived in Seoul or Gyeonggi Province and Honam district. The tissues from 43 Korean cadavers were digested with microwave digestion system and arsenic was determined by inductively coupled plasma mass spectrometer (ICP-MS). The mean recovery percentages of arsenic In liver were about 80％ and artenic concentrations in human tissues were almost uniform. The mean level of arsenic in internal tissues were at follow ; liver 44.556${\pm}$25.199 ppb, kidney cortex 42.652${\pm}$22.082 pub, lung 31.020 ${\pm}$ 17.504 ppb. cerebrum 35.703 ${\pm}$22.191 ppb, muscle 43.413${\pm}$26.619 ppb and skin 42.106${\pm}$25.8,11 ppb. No significant difference was found in the levels of arsenic between sexes. Meanwhile significant differences between districts where they had lived were found in all tissues tested. The levels of arsenic in the tissues of cadavers who had lived in Seoul Gyeonggi Province were higher than those of Honam district. In addition a positive correlation between As concentration and age was observed only in the cerebrum (p < 0.05). A significantly high correlations between tissues were observed in all tissues tested. This result also shows that the distribution of arsenic is uniform in internal tissues.

• Journal of Korea Water Resources Association
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• v.40 no.10
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• pp.823-832
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• 2007

In this study, the separation of short and long durations for estimation the parameters of IDF curve is suggested by using Multi-Objective Genetic Algorithm (MOGA). Objective functions are to minimize root mean squared error (RMSE) and relative RMSE between observed and computed values. The criteria for separation are two; the first one is to estimate more precisely the parameters of IDF curve and the second is to make a single IDF curve without non-continuous duration point. For this purpose 22 rainfall recording gauges operated by Korea Meteorological Administration are selected and three IDF curves that are used generally in South Korea are tested. The result shows that the IDF curve developed by Heo et al. (1999) would be the best of three tested IDF curves, and the suggested parameter estimation method using MOGA can compute more reliable parameters compared with empirical regression analysis.