• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.4
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• pp.561-568
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• 2021

In this study, in order to observe the change in the amount of Tire and Road Wear Particles and the ratio of tire components in it according to the tire wear resistance performance, carried out the evaluation by varying the vulcanization reaction design of the tire tread rubber. In addition, in order to improve the reliability of the evaluation of Tire and Road Wear Particles, the evaluation was performed indoor laboratory test equipment that simulates the condition on real driving to exclude various environmental influences including minerals, driver's habits, road surface, weather, tire structure and pattern designs. After the evaluation in closed space, it is estimated that the amount of collected Tire and Road Wear Particles is 84% compared to 100% of the tire and road wear loss weight, of which 96.4~97.7% was around the road and 2.3~3.6% was in the air. As a result of analy sis of the collected Tire and Road Wear particles, the tire component existed 63~75% in the Tire and Road Wear Particles depending on the wear resistance performance of the tire.

• Tunnel and Underground Space
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• v.34 no.1
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• pp.15-27
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• 2024

In this case study, detailed survey of the Excavation Damaged Zone (EDZ) evaluation for the deep geological repository for high level nuclear waste was conducted. Oversea and Domestic case studies were compiled and investigated. EDZ is considered a crucial factor in the performance assessment of spent fuel disposal, leading to numerous studies worldwide aiming to understand the characteristics of the EDZ and quantitatively assessment of its extent through field and laboratory tests at Underground Research Laboratory (URL) sites. To enhance the understanding of EDZ, this study begins with defining and exploring the history of EDZ, compiling factors influencing EDZ, and summarizing the impacts caused by EDZ. Subsequently, an analysis of EDZ and rock properties is performed, followed by presenting generalized outcomes, limitations drawn from previous research, and proposing future research directions.

• Economic and Environmental Geology
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• v.39 no.6 s.181
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• pp.699-710
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• 2006

Batch scale experiments to investigate the efficiency of the solidification process for metal mine tailing treatment were performed. Portland and MSG (micro silica pouting) cements were used as solidifier and three kinds of mine tailings (located at Gishi, Daeryang, and Aujeon mine) were mixed with cements to paste solidified matrices. Single axis com-pressible strengths of solidified matrices were measured and their heavy metal extraction ratios were calculated to investigate the solidification efficiency of solidified matrices created in experiments. Solidified matrices ($5cm{\times}5cm{\times}5cm$) were molded from the paste of tailing and cements at various conditions such as different tailing/cement ratio, cement/water ratio, and different cement or tailing types. Compressible strengths of solidified matrices after 7, 14, and 28 day cementation were measured and their strengths ranged from 1 to $2kgf/mm^2$, which were higher than Korean limit of compressible strength for the inside wall of the isolated landfill facility ($0.21kgf/mm^2$). Heavy metal extractions from intact tailings and powdered matrices by using the weak acidic solution were performed. As concentration of extraction solution for the powdered solidified matrix (Portland cement + Gishi tailing at 1:1 w.t. ratio) decreased down to 9.7 mg/L, which was one fifth of As extraction concentration for intact Gishi tailings. Pb extraction concentration of the solidified matrix also decreased to lower than one fourth of intact tailing extraction concentration. Heavy metal extraction batch experiments by using various pH conditions of solution were also performed to investigate the solidification efficiency reducing heavy metal extraction rate from the solidified matrix. With pH 1 and 13 of solution, Zn and Pb concentration of solution were over the groundwater tolerance limit, but at pH $1{\sim}13$ of solution, heavy metal concentrations dramatically decreased and were lower than the groundwater tolerance limit. While the solidified matrix was immerged Into very acidic or basic solution (pH 1 and 13), pH of solution changed to $9{\sim}10$ because of the buffering effect of the matrix. It was suggested that the continuous extraction of heavy metals from the solidified matrix is limited even in the extremely high or low pH of contact water. Results of experiments suggested that the solidification process by using Portland and MSG cements has a great possibility to treat heavy metal contaminated mine tailing.

• The Korean Journal of Pesticide Science
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• v.16 no.4
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• pp.364-368
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• 2012

In vivo experiments were carried out to investigate the effect of microbial agents on tomato disease occurrences in a sustainable tomato farm in Gong-ju, Chung-nam during 2 years (2010-2011). Two kind of commercial microbial agents (EXTN-1 and Cillus suspension concentrate) and 2 kind of microbial agents (Bacillus subtilis strain 'B4' and 'B17') developing by National academy of agricultural science were used in this study. In the 1st experimental year, the microbial agents were sprayed on leaves for 2-4 times at 1-2 weeks interval from 3 weeks after transplanting, and then disease occurrence were observed. As a result, the control efficacies of commercial EXTN-1 and Cillus suspension concentrate (SC) against gray mold were 59.6% and 50.5% in the treatment of 4 times foliar application at 1 week interval from 3 weeks after transplanting, and the control efficacy of commercial EXTN-1 SC against gray mold was 55.4% in the treatment of 3 times foliar application at 1 week interval from 4 weeks after transplanting. However, the control efficacies of EXTN-1 and Cillus SC were not enough for tomato crop protection against powdery mildew. In the 2nd experimental year, the microbial agents were treated following by the planned combination schedule of transplanting stage drip-watering, early stage root irrigation and early blooming stage foliar application. The control efficacies of EXTN-1 SC and B17 treatment following by transplanting stage drip-watering, 2 times root irrigation at 2 weeks interval root irrigation and 4 times foliar application at 1 weeks interval for gray mold management were 57.0 and 55.1%, respectively. In the case of same treatment for gray mold management mentioned at above, the control efficacies of EXTN-1 SC, B4 and B17 treatment for powdery mildew management were 50.5, 51.3 and 52.5%, respectively.

• Journal of Soil and Groundwater Environment
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• v.7 no.4
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• pp.77-86
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• 2002

Surfactant enhanced in-situ soil flushing was performed to remediate the soil and groundwater at an oil contaminated site, where had been used as a military vehicle repair area for 40 years. A section from the contaminated site (4.5 m $\times$ 4.5 m $\times$ 6.0 m) was selected for the research, which was composed of heterogeneous sandy and silt-sandy soils with average $K_d$ of 2.0$\times$$10^{-4}$cm/sec. Two percent of sorbitan monooleate (POE 20) and 0.07% of iso-prophyl alcohol were mixed for the surfactant solution and 3 pore volumes of surfactant solution were injected to remove oil from the contaminated section. Four injection wells and two extraction wells were built in the section to flush surfactant solution. Water samples taken from extraction wells and the storage tank were analyzed on a gas-chromatography (GC) for TPH concentration in the effluent with different time. Five pore volumes of solution were extracted while TPH concentration in soil and groundwater at the section were below the Waste Water Discharge Limit (WWDL). The effluent TPH concentration from wells with only water flushing was below 10 ppm. However, the effluent concentration using surfactant solution flushing increased to 1751 ppm, which was more than 170 times compared with the concentration with only water flushing. Total 18.5 kg of oil (TPH) was removed from the soil and groundwater at the section. The concentration of heavy metals in the effluent solution also increased with the increase of TPH concentration, suggesting that the surfactant enhanced in-situ flushing be available to remove not only oil but heavy metals from contaminated sites. The removal efficiency of surfactant enhanced in-situ flushing was investigated at the real contaminated site in Korea. Results suggest that in-situ soil flushing could be a successful process to remediate contaminated sites distributed in Korea.

• Journal of Practical Agriculture & Fisheries Research
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• v.17 no.1
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• pp.85-92
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• 2015

The experiment was conducted to evaluate rice growth and yield as affected by different coating and covering materials such as a iron, silicate, iron and silicate mixture of rice seeds in farmer's rice growing field. The tiller number was 36.7 at iron-coated seeds, 32.8 at silicate-covered seeds, 30.3 at iron and silicate mixture coated seeds and 30.2 at untreated control in 44days after seeding. The seedling height was 38.2cm of iron and silicate mixture, 37.7cm of untreated control, 36cm of iron-coated and 35.7cm of silicate covered seeds in 43days after seeding. At 75days after seeding rice tiller number was 153 of iron-coated seeds, 152 of silicate-covered seeds, 147 of untreated seeds and 141 of iron and silicate mixture-coated seeds and also there were different plant height growth of 87.4cm in silicate-covered seeds, 85.7cm in iron and silicate mixture, 85.4cm in untreated control and 83.0cm in iron-coated seeds. The panicle length was of 21.0cm in iron and silicate mixture coated seeds, 20.8cm in silicate covered seeds, 20.7cm in untreated control seeds and 20.6cm in iron-coated seeds. The panicle number was 464 at iron-coated seeds, 404 at untreated control seeds, 427 at silicate-covered seeds and 412 at iron and silicate mixture coated seeds. The spikelet number per m² was of 32,503 in iron-coated seeds, 31,813 in silicate-covered seeds, 29,646 in untreated control, 28,896 in iron and silicate mixture coated seeds. The ripened ratio of rice grain was of 94.5% at iron-coated seeds, 93.9% at iron and silicate mixture coated seeds, 93.6% at silicate covered seeds and 93.2% at untreated control seeds. The rice yield was of 591kg/10a at iron-coated seeds, 580kg/10a at silicate-covered seeds, 571kg/10a at iron and silicate mixture-coated seeds and 539kg/10a at untreated control.

• Journal of Practical Agriculture & Fisheries Research
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• v.11 no.1
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• pp.79-94
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• 2009

The research project was conducted to develop a paper bagging machine for grape. This technology was aimed to highly reduce a labor for paper bagging in grape and bakery. In agriculture labor and farm population has rapidly decreased since 1980 in Korea so there was so limit in labor. In particular there is highly population in women and old age at rural area and thus labor cost is so high. Therefore a labor saving technology in agricultural sector might be needed to be replaced these old age with mechanical and labor saving tool in agriculture. The following was summarized of the research results for development of a paper bagging machine for grape. 1. Development of a new paper bagging machine for grape - This machine was designed by CATIA VI2/AUTO CAD2000 programme. - A paper bagging machine was mechanically binded a paper bag of grape which should be light and small size. This machine would be designed for women and old age with convenience during bagging work at the field site. - This machine was manufactured with total weight of less than 350g. - An overage bagging operation was more than 99% at the actual field process. - A paper bagging machine was designed with cartridge type which would be easily operated between rows and grape branches under field condition. - The type of cartridge pin was designed as a C-ring type with the length of 500mm which was good for bagging both grape and bakery. - In particular this machine was developed to easily operated among vines of the grape trees. 2. Field trials of a paper bagging machine in grape - There was high in grape quality as compared to the untreated control at the application of paper bagging machine. - The efficiency of paper bagging machine was 102% which was alternative tool for the conventional. - The roll pin of paper bagging machine was good with 5.3cm in terms of bagging precision. - There was no in grape quality between the paper bagging machine and the conventional method. - Disease infection and grape break was not in difference both treatments.