• The Korean Journal of Pesticide Science
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• v.9 no.3
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• pp.231-236
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• 2005

This study was conducted to determine the amounts of pesticide residues after treatment of criterion dose with 4 pesticides(tolclofos-m, folpet, procymidone, and triflumizole) under cultivated period and to compare the biological half-life of pesticides with 6 kinetic models(first, zero and second order kinetics, power function, elovich and parabolic model) and to establish proposed field tolerance using biological half-lives. Recovery of 4 pesticides form strawberry was ranged from 85.1 to 105.5%. For all of 4 pesticides, dissipation rate was over 73% at 5 days after application. Among 6 kinetic models, first order kinetic model (FO) was best fit to describe the relationship between residual pattern of pesticides and time. Therefore, half-lives were calculated by FO for establishing the field tolerance. These results showed that half-life should be calculated by comparative best fit kinetic model and field tolerance can help to prevent unacceptable agricultural products from marketing. It is good for both consumers and farmers having safe agricultural products and financial benefits, respectively.

• Journal of the Korea institute for structural maintenance and inspection
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• v.16 no.5
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• pp.19-28
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• 2012

In this study, cause of longitudinal crack which is found on duct slab of road tunnel is studied. In-depth investigation, such as visual inspection, non-destructive testing and geometrical surveying of duct slab, is carried out. In order to perform cause analysis, the investigated results are compared to the results of numerical analysis. Many factors, which cause longitudinal crack, are classified as constrained condition of the duct slab, location of the rebar, temperature, shrinkage and so on. According to the classified causes of longitudinal crack, numerical analysis is performed considering construction stage of the tunnel lining. Especially, in order to predict shrinkage stain due to discrepancy of curing date, ACI-209 model, KCI structural design code and other researcher's shrinkage test results are compared. The results show that shrinkage strain is one of the main factors causing longitudinal crack. Other investigated tunnels are classified along with the construction method of duct slab and patterns of cracks. As a result, improving ways to construct duct slab are suggested.

• Restorative Dentistry and Endodontics
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• v.23 no.1
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• pp.357-365
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• 1998

목적: 치과용 수복재료의 방사선 불투과성은 매우 다양하다. 따라서 다양한 수복재료의 방사선 불투과성을 인지하여 치질과 비교하면 이차우식의 진단에 도움이 될 수 있다. 도재의 방사선 불투과성에 따라 적절한 luting cement의 선택이 가농해진다. 수복재료의 방사선 불투과성은 알루미늄 step wedge 의 후경과 방사선 불투과성과의 상관관계 의해 측정된다. 본 연구의 목적은 CAD/CAM용 도재와 이틀의 접착에 쓰이는 접착재료의 방사선 불투과성을 조사해 적절한 재료의 선택과 이차우식 진단의 효율결정에 도움이 되게 하는데 있다. 방법: 본 실험에서는 CAD/CAM용 도재인 Vita MarkII, Dicor MGC와 이의 접착에 사용되는 Z-100, 그리고 luting cement인 Duo cement, Scotchbond resin cement를 사용해 방사선 불투과성을 측정하였다. 시편 제작을 위해 도재를 저속절단기로 두께 2mm, 3mm로 절단하였으며 Z-100과 cement시편은 두께 2mm와 3mm, 직경 7.0mm의 금속 주형을 제작한 후 재료를 양쪽 면에 유리판을 대고 조임쇠로 압접하였으며 광조사기를 사용하여 각 재료마다 두 가지 두께로 10개씩 100개의 시편을 제작하였다. 치질의 시편을 얻기 위해 교정 목적으로 최근에 발거된 정상적인 상악 소구치를 저속 절단기를 사용하여 협설측 교두정을 기준 삼아 2mm, 3mm 두께로 절단하였으며 방사선 불투과성의 기준을 위해 12개의 step으로 구성된 12mm두께의 aluminum step wedge를 사용하였다. Kodak E-Speed occlusal film에 aluminum step wedge와 시편들을 위치시킨 후 70kVp, 7mA, 2.16mm aluminum filtration으로 고정된 dental X-ray unit을 사용하여 target과 film 사이의 거리는 25cm, 노출시간은 0.2초로 하여 방사선 촬영을 한 다음, 현상된 방사선 사진상에 나타난 방사선 불투과성을 X-rite 301 densitometer를 이용하여 측정한 값들의 평균을 냈다. 얻어진 결과는 one-way ANOVA Duncan test(P<0.01)로 검증하였다. 결론: 1. Dicor MGC의 방사선 불투과성은 법랑질보다 약간 높게 나타났다.(P<0.01) 2. Vita Mark Il는 상아질보다 낮은 방사선 불투과성을 보였다.(P<0.01) 3. Z-100과 Luting cement들의 방사선 불투과성은 법랑질보다 높았다. Duo cement가 방사선 불투과성이 가장 높았고 그 다음이 Z-100, 그리고 Scotchbond resin cement 순이었다. 4. Z-100과 2종류의 방사선 불투과성 luting cement들은 Vita Mark II 와 같이 사용하면 2차우식 진단에 도움이 된다.

• Journal of Platform Technology
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• v.11 no.2
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• pp.54-65
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• 2023

Due to the nature of electric vehicles, the batteries used for electric vehicles have a very large rated capacity. If an electric vehicle runs for a long time or an electric vehicle is abandoned due to a traffic accident, the electric vehicle battery becomes a waste battery. Even in vehicles that are being abandoned, the remaining capacity of waste batteries for electric vehicles is sufficient for other purposes. Waste batteries for automobiles are very expensive, so they need to be recycled and reused, but there was a problem that the standards for measuring the performance grade of waste batteries for recycling and reuse were insufficient. As a method for measuring the remaining capacity of waste battery, the most stable and reliable method is to measure the remaining capacity of battery using full charge and discharge. However, the inspection method by the full charging and discharging method varies depending on the capacity of the battery, but it takes more than a day to inspect, and many people are making great efforts to solve this problem. In this paper, an electric vehicle battery residual capacity analysis technique using voltage deviation between cells was studied and analyzed as a method to reduce inspection time for electric vehicle batteries. To this end, a full charging and discharging-based capacity measurement system was constructed, experimental data were collected using a nose or waste battery, and the correlation between the voltage deviation and the remaining capacity of the battery pack was analyzed to verify whether it can be used for battery inspection.

• The Korean Journal of Nuclear Medicine Technology
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• v.17 no.1
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• pp.53-61
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• 2013

Objectives: It is certain that Radioactive iodine thyroid uptake(RAIU) rate should be measured with the standard counts considering the thyroid gland depth in enlarged thyroid patients for the variation from geometric factors. The purpose of this paper is to consider the effects of geometric factors according to detector to source distance and the effective thyroid depth on RAIU rate with experiment test. Materials and Methods: I-131 370 kBq ($10{\mu}Ci$) point source was measured by Captus-3000 thyroid uptake system (Capintec, NJ, USA) with a change Detector-Source Distance from 20 cm to 30 cm at an interval of 1 cm. And we changed the Neck phantom surface-Source Depth in the phantom with 1 cm, 2 cm, 5 cm using the neck phantom in order to reproduce the effective thyroid depth. Results: Every experimental group follows power curve as inverse square curve ($$R2{\geq_-}0.915$$). The average count rates in the case not using a phantom and the every case applied the effective thyroid depth using a phantom was not identical each other. There was significant fluctuations upon the effective thyroid depths applied the effective thyroid depth above 1 cm in $364.4 keV{\pm}10%$ energy ROI (p<0.01). There was not significant difference between the count rates of 1 cm and 2 cm in $364.4keV{\pm}20%$ and $637.1keV{\pm}6.2%$ (p=0.354, p=0.397). In assumed RAIU rate from regression equation, $364.4keV{\pm}20%$ was lower difference than $364.4keV{\pm}10%$ as 6.42% and 5.09% per 1 cm. Every change of count rate upon depth appears decreased line on Linear Regression, but the case of $284.3keV{\pm}10%$ increased only. And also, The graphs of coefficient of variation upon depth increased as straight line on every experimental group. Conclusion: The result appears that application of $364.4keV{\pm}20%$ energy ROI is more suitable for reducing error from the effective thyroid depth. And also, we can estimate the error of 20 cm should be highly reduced than 30 cm for Inverse Square Law. Therefore, If there is not information of the thyroid depth, it is considered that the error from thyroid depth can reduce through set up energy ROIs for $364.4keV{\pm}20%$, and increase Detector-Source Distances.

• Journal of Life Science
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• v.25 no.3
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• pp.329-335
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• 2015

This study was performed to determine the optimal ratio of Petasites japonicus, Luffa cylindrica, and Houttuynia cordata, all of which are supposed to have anti-respiratory disease effects, such as against rhinitis. The experiment incorporated a mixture design and included 12 experimental points with center replicates for three different independent variables (Petasites japonicus 30~70%; Luffa cylindrica 10~30%; and Houttuynia cordata 10~30%). Based on this design, the mixture was extracted in hot water at 121℃ for 45 min and anti-allergy and anti-microbial activities were observed. The response surface and trace plot described for the anti-allergy activity showed Petasites japonicas was a relatively important factor. The correlation coefficient (R²) value 82.10% for the inhibition effect of degranulation was analyzed by the regression equation. The analysis of variance showed the model fit was statistically significant (p<0.05). The optimal ratio of the mixture was Petasites japonicus 0.75%, Luffa cylindrica 0.11%, and Houttuynia cordata 0.14%. The anti-microbial activity for each extraction of the mixture was valid on gram-positive, such as Staphylococcus aureus (KCCM 40881) and Staphylococcus epidermidis (KCCM 35494), while it was less effective on gram-negative, such as Escherichia coli (KCCM 11234) and Pseudomonas aeruginosa (KCCM 11328).

• Korean Journal of Environment and Ecology
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• v.21 no.3
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• pp.213-222
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• 2007

The goal of the study is to provide basic information that can be used to come up with environmental interpretation methods that are appropriate to the conditions of urban parks. For this matter, research was conducted to find out whether the environmental interpretation that was provided to the visitors of the World Cup Park Visitor Center encouraged them to become interested in the environment and to understand how such environmental interest was related to the level of satisfaction that the visitors were experiencing from their visits to the park. At the same time, the research was designed to find out whether the park's visitors were affected differently in terms of their environmental interests and their experience depending on the two different types of environmental interpretations; Interpreter's Interpretation and Self-guiding Interpretation. Experimental result showed no statistically meaningful correlation between environmental interpretation and environmental knowledge, though the experimental group subjected to environmental interpretation was found to have higher environmental knowledge than that of the control group, which was not subjected to environmental interpretation. As for the correlation between environmental knowledge, which was acquired through environmental interpretation, and environmental interest, the group, which showed big changes in terms of the volume of environmental knowledge, was found to have higher environmental interest than that of the group, which recorded a low level of changes in the volume of environmental knowledge. Also, the difference in their level of environmental interest was big enough to be acknowledged statistically. Also environmental interest, which was created thanks to environmental interpretation, was found to affect the level of satisfaction visitors feel when visiting the park. Even though the study was intended to find out how environmental interpretation affects park visitors by means of analysis that can be proved based on facts, it was difficult to control some of the variables due to the circumstances under which the experiments were conducted. Despite this, the study can be considered meaningful in the fact that the researches and experiments were conducted at a park that is actually visited by people. It is also believed that as one of the first studies done on the World Cup Park, it could serve as a basis upon which future studies could be carried out.

• Korean Journal of Agricultural Science
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• v.10 no.2
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• pp.354-364
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• 1983

Confonmation of (Z)-cinnamonitrile have been studied by molecular orbital theoretically using extended Huckel theory(EHT) and CNDO/2 molecular orbital calculation methods. The results indicate that the stability of conformation is(Z)-gauch>(Z)-planar. The rate constants for alkalie hydrolysis of cinnamonitrile at pH 7.0-14.0 range have been determined by ultra-violet spectrophotometry in 50% methanol at $25^{\circ}C$ and the following rate equation which can be applied over wide pH range was obtained; $${\therefore}k=({\frac{1.41{\times}10^{-14}+1.21{\times}10^7/[H_3O^+]}{2.65{\times}10^{-7}+1.64/[H_3O^+]})+9.14{\times}10^9/[H_3O^+]$$ The rate equation reveals that, at pH 7.0-10.0, the reaction is initiated by the addition of water molecule to unsaturated cabon-carhon double bond of cinnamonitrile and ${\alpha}C-{\beta}C$ bond scission follow subsequently in neutral and alkalie media. At pH 12.0-14.0, in strong alkalie solution, that so-called Michael type nucleophilic addition that the over-all rate constants is only dependent upon the concentration of hydroxide ion occurs competitively and are very complicated. Hence, the reaction mechanism of alkalie hydrolysis of cinnamonitrile which did not carefully before can be fully explained.

• Korean Journal of Soil Science and Fertilizer
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• v.8 no.2
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• pp.69-80
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• 1975

Relationships between yield and various nitrogen efficiencies, between efficiencies and between efficiency and nitrogen uptake amount of rice plant were proposed and tested using data from N.P.K simple trials about 30 to 50 locations, for three years. Established relationships are well in accordance with experimental results by showing highly significant correlations between them. The overall indications are that high yielding capacity of fields with fertilizer application, depends primarily on high fertilizer nitrogen uptake by increasing fertilizer use efficiency (Eu), secondly the efficiency (Ef) of absorbed fertilizer nitrogen (Nf) and fertilization efficiency (Fe) and also depends much on nitrogen efficiency for grain yield (E) to great extend and that the efficiency (Es) of soil nitrogen (Ns) contributes to E more than Ef does. All nitrogen efficiencies are negatively correlated with the uptake amount of corresponding nitrogen and counterpart efficiency. Es and Ef could be determined firstly by difference method and secondly E versus Cs (Cs=Ns/Ns+Nf) plotting and thirdly E-Cs plotting with labelled fertilizermethod using the equation E=Es Cs+B where B=Ef Cf but a constant under the given condition and at last Y-Ns plotting with labelled fertilizer using Eq Y=$Es{\cdot}Ns+B$ where B=$Ef{\cdot}Nf$. Es which seems not much variable from field to field is mostly greater (about 80% of tested fields) than Ef which is much variable and depends much on fertilizer form. The relationships tested and well agreed are as follows: 1. Y=$Es{\cdot}Ns+Ef{\cdot}Nf$ (Y is yield) 2. E=$Es{\cdot}Cs+Ef{\cdot}Cf$ where Cf=Nf/Nf+Ns 3. E=b-aN where E=E, Es or Ef and N=N, Ns or Nf respectively, (E=Y/N, N=Nf+Ns), b is theoretical maximum under the given system and a is tangent at N=O of the curve, Y=EN. 4. Fe=Ef Eu and Se=$Es{\cdot}Eu$ where Se is efficiency of soil available nitrogen. 5. E=$(Se{\cdot}Cs+Fe{\cdot}Cf)/Eu$ 6. Y=$Es{\cdot}Eu{\cdot}Sf+Ef{\cdot}Eu{\cdot}Fn$or Y=$Es{\cdot}Eu{\cdot}Ea{\cdot}Sn+Ef{\cdot}Eu{\cdot}Fn $where Sf=$Ea{\cdot}Sn$, Ea is soil available nitrogen equivalent to fertilizer(Sf) divided by total soil nitrogen (Sn).

• Journal of Bio-Environment Control
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• v.28 no.4
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• pp.286-292
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• 2019

This study aimed to investigate the suitable of layer on growth of six baby leaf vegetables using existing facilities and equipment in rice seedling nursery. Three kinds of Lactuca(lettuce 'Jinppallola' and 'Romain white', and indian lettuce), two of Brassica(tatsoi and red tatsoi) and amaranth were used as the materials. After sowing, the rice seedling tray was placed in multi bench system($L120{\times}W60{\times}H195cm$, 10th floor), which were low(1st) layer above 15cm, middle(4th) layer above 115cm and high(7th) layer above 175cm apart from ground. Irrigation was sprayed 2~3 times a day using a automatic irrigation system. The growth characteristics and leaf color were investigated when leaf vegetables were reached the optimum size(within 10cm of plant height). During the culture periods(29th Jun.~31th Jul. 2017), daytime average temperature was $27.4{\sim}28.3^{\circ}C$ regardless of layers but solar irradiance was higher in the high-layer than low and middle-layer of 37% and 22%, respectively. The leaf length, leaf width and number of leaves in middle and high-layer have a tendency to increase but, fresh weight was different according to the layer. When the correlation between accumulation radiation and growth was analyzed, all of growth factor of Amaranth showed a high correlation and other cultivars showed correlation with each growth factors. As a result, It is suitable that amaranth and red tatsoi for high-layer, Indian lettuce and tatsoi for middle and high-layer and 'Romain white' for middle-layer. The growth of red lettuce 'Jinppallola' was good at low layer, but leaf color expression was poor. So the high layer is suitable for 'Jinppallola'.