• Journal of Korea Water Resources Association
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• v.43 no.11
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• pp.967-976
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• 2010

AFDA (Approximate Full Distribution Approach) model of FORM (First-Order Reliability Model) which can quantitatively calculate the probability that storm sewer reach to performance limit state was developed in this study. It was defined as a failure if amount of inflow exceed the capacity of storm sewer. Manning's equation and rational equation were used to determine the capacity and inflow of reliability function. Furthermore, statistical characteristics and distribution for the random variables were analyzed as a reliability analysis. It was found that the statistical distribution for annual maximum rainfall intensity of 10 cities in Korea is matched well with Gumbel distribution. Reliability model developed in this study was applied to Y shaped storm sewer system to calculate the probability that storm sewer may exceed the performance limit state. Probability of failure according to diameter was calculated using Manning's equation. Especially, probability of failure of storm sewer in Mungyeong and Daejeon was calculated using rainfall intensity of 50-year return period. It was found that probability of failure can be significantly increased if diameter is decreased below the original diameter. Therefore, cleaning the debris in sewer pipes to maintain the original pipe diameter should be one of the best ways to reduce the probability of failure of storm sewer. In sewer system, two sewer pipes can flow into one sewer pipe. For this case, probability of system failure was calculated using multiple failure mode. Reliability model developed in this study can be applied to design, maintenance, management, and control of storm sewer system.

• Korean Journal of Food Science and Technology
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• v.45 no.4
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• pp.409-415
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• 2013

Post-harvest fungicide residue was measured in citrus fruits. Samples were collected from local markets in Seoul and analyzed using liquid chromatography coupled with mass spectrometry (LC-MS). LC-MS results were validated for the assay of pesticides by using linearity, accuracy, precision, and limits of detection and quantification. The linearity in the concentration ranged from 0.005 to 2.0 mg/kg ($R^2$ >0.999). Sample recoveries ranged from 80.2 to 98.3% with relative standard deviations below 4.0% for spiking levels from 0.01 to 1.0 mg/kg. The limits of detection ranged between 0.002 and 0.008 mg/kg, and the limits of quantification ranged between 0.006 and 0.027 mg/kg. The highest residue levels for carbendazim, thiabendazole, imazalil, and azoxystrobin in citrus fruits were 0.541, 0.958, 0.721, and 0.052 mg/kg, respectively. The pesticide residues found in citrus fruits were blow maximum residue limits (MRLs) and are not a serious public health problem.

• Weed & Turfgrass Science
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• v.1 no.4
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• pp.13-17
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• 2012

A field experiment was conducted to investigate the effect of Acalypha australis occurrence on the growth and yield of soybean, to predict the reduction rate of soybean yield caused by competing with A. australis and to establish the economic threshold of A. australis for soybean cultivation. As the density of A. australis increase, the height and stem length of soybean were not affected by the competition with A. australis, however, the yield of soybean was decreased as 11~51% as compared with weed-free condition. The relationship between weed density and soybean yield was established as Y=415.5 / (1+0.003356X) and the reduction rate of soybean yield were predicted from this equation. Compared with the weed-free condition, the reduction rate of soybean yield were calculated as 0.3~9%, 17~29%, and 40~46% when the density of A. australis were 1~30, 60~120, and 200~250 plants $m^{-2}$, respectively. The economic threshold level of A. australis for soybean cultivation was established as 6.3 plants $m^{-2}$ from the Cousens' equation.

• Journal of the Korean Geotechnical Society
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• v.28 no.7
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• pp.55-65
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• 2012

Total reduction factor that is used when calculating allowable tensile strength of geogrids is made by multiplying the installation damage reduction factor ($RF_{ID}$), chemical degradation reduction factor ($RF_D$), and creep reduction factor ($RF_{CR}$) etc. In case of a model estimating allowable tensile strength considering reduction factor over the short-term tensile strength of geogrids, it has a limit of not considering interaction force between reduction factors. Junction strength comes to be reduced by installation damages or chemical degradation in the same way as tensile strength. Single junction test method cannot properly test damaged samples and shows large deviations as it does not consider scale effect. Besides, regarding calculating shear strength, no reasonable study on reduction factors was conducted yet. Therefore, in this study, reduction factors that may affect the long-term performance of geogrids were revaluated considering various conditions and accurate long-term allowable tensile strength was calculated considering interrelation between reduction factors. Creep results after installation damage and chemical resistance test showed lower value than calculated value according to GRI GG-4. After the installation damage test and the chemical resistance test, the reduction factor of junction strength was less than that of tensile strength. Shear strength before and after installation damage showed no change or increase.

• Korean Journal of Environmental Agriculture
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• v.34 no.2
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• pp.120-127
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• 2015

BACKGROUND: Supervised residue trials were conducted to establish pre-harvest residue limit(PHRL), a criterion to ensure the safety of the pesticide residue in the crop harvest, of amisulbrom for winter-grown cabbage in two fields. Following to application of amisulbrom on the crop, time-course study was carried out to obtain the amisulbrom dissipation of statistical significance which enabled to calculate the predicted values of PHRL. METHOD AND RESULTS: During cultivation under greenhouse condition, samples of winter-grown cabbage were collected at 0, 1, 3, 5, 7 and 10 days after amisulbrom application, and subjected to residue analysis. Analytical method was validated by recoveries ranging 93.7~100.0% as well as limit of quantitation(LOQ) of 0.04 mg/kg. Amisulbrom residues in winter-grown cabbage gradually decreased as time elapsed. The dissipation rate of the residue would be affected by intrinsic degradation along with dilution by the cabbage growth. The decay pattern was well fitted by the simple first-order kinetics. CONCLUSION: Biological half-lives of amisulbrom in winter-grown cabbage ranged 3.7~4.1 days in two field conditions. Based on the regression of amisulbrom dissipation, PHRLs of amisulbrom in winter-grown cabbage were recommended as 8.86~9.47 and 4.21~4.35 mg/kg for 10 and 5 days before harvest, respectively.

• International Commerce and Information Review
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• v.16 no.4
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• pp.79-102
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• 2014

A parallel importation is a non-counterfeit product imported from another country without the permission of the intellectual property owner. It is caused by price differences between countries. Therefore parallel importation are implication in issues of international trade and intellectual property rights(hereafter referred as IPR). This paper provides parallel importation issues of Korea and China under the IPR laws such as patent, trademarks, copyright and analyzes difference between two countries. In China, patent law regulates exhaustion rights which is based theory of a parallel import for the first time unlike trademark law and copyright law. On the other hands, Korea rules parallel importing under Korean customs regulations. In conclusion, two countries have no provisions that advocate a parallel import under IPR laws. This paper suggests some improvements to overcome the limitation of current regulation system and avoid trade friction between two countries. First of all, two countries should clearly make a rule about parallel import in IPR law such as definition of parallel importation, genuine goods, permission conditions, importing proses, penalty and remedy etc. Secondly, two countries should prohibit an abuse of a exclusive import agent's rights and manage a parallel importer not to cause consumer's complain about goods to expansion parallel imports. Finally, two countries should cooperate not to cause disputes about this issue with a communication channel.

• The Korean Journal of Pesticide Science
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• v.21 no.1
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• pp.62-67
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• 2017

In this study, the residue patterns of flubendiamide and pyriofenone registered in the strawberry were investigated to predict pre-harvest residue limit (PHRL). The samples were harvested at 0, 1, 2, 3, 5, 7, 10 days after treatment and the pesticide residues were analyzed by HPLC/UVD. The limit of quantification (LOQ) was $0.01mg\;kg^{-1}$ for flubendiamide and pyriofenone. The recovery levels of flubendiamide and pyriofenone were $90.9{\pm}2.2%$ and $81.9{\pm}0.8%$, $87.7{\pm}2.1%$ and $85.3{\pm}1.1%$ for spiked levels of 0.01 and $0.1mg\;kg^{-1}$, respectively. The values of biological half-lives for field 1 and field 2 were 8.1 and 7.2 days for flubendiamide, 7.0 and 6.9 days for pyriofenone. According to these results, we recommends the level of PHRL on strawberry for flubendiamide and pyriofenone as 1.87 and $3.76mg\;kg^{-1}$ at 10 days before harvest, respectively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.6
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• pp.375-381
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• 2018

This study was performed to investigate the residual characteristics of the insecticide dinotefuran in asparagus under greenhouse conditions from July to August and consequentially to obtain basic data for guidelines on the safe use of this pesticide in asparagus. Residues of dinotefuran in young stem of asparagus before and after growing mother stem were analyzed from samples collected at 0, 1, 3, 5, and 7 days after single application of a commercial formulation of dinotefuran (wettable powder, 10%) at the recommended dose (2,000 times dilution). The residue of dinotefuran in young stem of asparagus was analyzed by HPLC-UVD, and recovery of dinotefuran in young stem was tested at 0.5 and 1.0 mg/kg concentrations. As a result, the limit of quantitation (LOQ) of dinotefuran was 0.01 mg/kg, and the recovery of dinotefuran was in the range of 83.3-94.0% with a coefficient of variation less than 10%. Residues of dinotefuran in young stem of asparagus before and after growing the mother stem were lower than the tentative limit (0.05 mg/kg) from 5 and 3 days after single application, respectively. Based on these results, single application of dinotefuran (wettable powder, 10%) at the recommended dose at 7 days before harvest would have no deleterious effects on safety issues concerning pesticide residue. This result might provide basic information to construct guidelines for the safe use of dinotefuran in asparagus.

• Land and Housing Review
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• v.2 no.3
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• pp.287-297
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• 2011

This paper presents the results of performance verification tests of the isolated flat plate apartment building with the laminated rubber bearings. The shaking table test is carried out in CABR(China Academy of Building Research) with two 1/10 scale isolation and non-isolation models under 4 excitation waves. The shaking table test is proceeding from x axis, y axis and x+y axis with different amplitude of acceleration values. The results show that, to non-isolated model, the natural vibration period is remarkably decreased and entered non-linear condition after moderate earthquake. Its accelerations become lager with increasing storey number and completely collapsed under large earthquake. The inter-storey shifts largely exceed the limit values of regulated displacement angles. But to isolated model, the natural vibration period of isolated modal is almost the same in all conditions and still in its elastic condition. The earthquake loading is greatly reduced and the accelerations of superstructure are greatly reduced. The inter-storey drifts are very small and can be neglected. The isolated model is in translational state and can be seen as a rigid whole. The displacements of isolation layer are in the allowable range. This experiment demonstrates that the seismic isolation is very effective to mitigate the influence of earthquake on structures and it is possible to increase the serviceability due to decrease the floor acceleration. facilities from their good states that is superior to non-isolated structure.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.6C
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• pp.231-240
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• 2011

Various pile load tests were carried out at Gwangyang district for 10 different piles in order to analyze the characteristcs of steel pile using high strength steel and high driving energy. Pile drivability results showed that PHC piles needed highest total blow count even with the shortest pile length and high strength steel pipe piles showed smallest total blow count eventhough driven to a more hard ground condition with longer pile length. Pile dynamic analysis results showed that for PHC pile and general steel pipe pile the allowable pile design load was decided by the allowable material strength but for high strength steel pipe pile the design load can be decided according to the ground bearing capacity. Static load test and load transfer test results showed that the pile design efficiency could be improved over 80% allowing lesser number of piles necessary for a more economical solution. Set-up effects was analyzed and regression equation for the site ground condition was derived. Bearing capacity was checked with widely used design equation and the limitation of current design method and future technology development on this subject is dicussed in this paper.