• Korean Journal of Soil Science and Fertilizer
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• v.7 no.3
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• pp.185-191
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• 1974

Incubation and pot studies were conducted with upland soils for a study on determination of the lime requirement based on exchangeable alumium content. The results obtained are as follows; 1. Results of chemical analysis of upland soils show that pH varies from 5.0 to 5.4, and exchangeable Al moves with the range of 1.3-3.0m.e/100gr. Exchangeable Al decreases with years of cultivation. 2. Incubation studies shows that on acid mineral soils almost all exchangeable Al, on average 95% was neutralized with the lime to neutralized 100% exchangeable Al. On volcanic ash soil, however, only 65.5% was neutralized with the lime estimated to neutralize the equivalent of 200% exchangeable Al. The latter has required more lime. 3. The pH of mineral soils is on the average increased from an initial 5.2 to 6.3 when 95% of exchangeable Al is neutralized, whereas that on volcanic ash soil is increased from an initial 5.3 to 5.5 only when lime is applied at rate to neutralize the equivalent of 200% exchangeable Al. 4. A high correlation coefficient (r=0.99) was obtained between exchangeable Al and exchangeable acidity. This indicates that exchangeable acidity is primarly a result of exchangeable Al. 5. In pot experiments with soybean cultivated on one of the hill land soils (Songjoong soil) the application of fused phosphate and triple superphosphate based on a 5% saturation rate ($P_2O_5$ 32.1 kg/10a) showed that the liming factor for calculation of the optimum lime requirements based on exchangeable acidity was 0.594 for fuses phosphate or 1.132 for tripple superphosphate, and optimum pH is approximately 6.0 and optimum neutralization rate of exchangeable Al is 80-90%.

• Applied Biological Chemistry
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• v.49 no.1
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• pp.30-34
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• 2006

The wastewater was quickly and fastly cleared by the peel extracts of astringent persimmon fruits. The degree of clearness increased with increasing concentrations (400-600 mg/l) of the peel extracts of astringent persimmon fruits. The removal rates of T-P and CODcr in wastewater with lime and the peel extracts of astringent persimmon fruits were lower than ferric chloride and aluminium sulfate at 100-200 mg/l concentration but higher at above 300 mg/l concentration. The removal rate of T-P increased with increasing concentration of the peel extracts of astringent persimmon fruits.

• Journal of radiological science and technology
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• v.28 no.4
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• pp.301-306
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• 2005

Purpose : The goal of this study was to survey the quality control of mammographic phantom images in some area. Methods : Between May and June, 2005, I have got a total of 47 mammographic phantom images collected from 49 hospitals and were analized about phantom score of fibrous, speck, tumor with enlargement scope. By critic level of experimental mammographic phantom case images, classified through the pass case that fibrous score 4, speck score 3, tumor score 3 over. Result : It passed 33case (70.3%), failed 14 case (29.7%) about 47 case. Passing case images showed tube voltage $23{\sim}30\;kVp$, tube current $20{\sim}60\;mAs$, photographic density $0.48{\sim}1.77$ Conclusion : It passed case about 70.3% of mammographic phantom image in some area. Optimum range of tube voltage, tube current, photographic density have to use to get fine quality of mammographic images.

• Korean journal of applied entomology
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• v.7
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• pp.77-81
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• 1969

The effects of submerged method. Zentmyer's drench method. pot test and field test with materials such as Carbamisol (ammonium methyldithiocarbamic acid $30\%$), NCS (ammonium N-methyldithiocarbamate$50\%$, Similuton(ethyl phenethynylmeroury $3.3\%$), Soill(N-ethylmercuric p-toluensulfonanilide $4\%$, Captan (N-trichloromethylthio-1, 2, 3, 6-tetra-hydrophthalimide $80\%$), Difolatan(N-tetrachloroet-hylthio 4cyelohexeno-1,2-dicarboximide $80\%$, Grand(2, 3-dibromepropionitryl $20\%$, trichloronitroethylene $20\%$) and Calcium hydroxide upon occurrence of Fusarium wilt of cucumber were studied. The results are summarized as follows. 1. According to submerged method, all the compounds tested were highly inhibitory to mycelial growth of Fusarium oxysporum f. cucumerinum except calcium hydroxide. But several compounds were no inhibitory to the causal fungus except Grand and Similuton, with Zentmyer's drench method. 2. Grand was the most effective fungicide for the control of cocumber Fusarium wilt in the pot test, and followed by Similuton and calcium hydroxide. The population of Fusarium oxysporm was markedly reduced when soil was treat with Grand compared with other chemicals. 3. Fungicidal effects upon occurrence of Fusarium wilt of cucumber under the field experiment varied with the fungicides. Of the fungicides tested. Grand gave the best control, and followed by Difolatan.

• Journal of the Korea Convergence Society
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• v.10 no.2
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• pp.29-34
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• 2019

In this study, we measure dose against various density and thickness using phantom to compare FFDM to DBT of Digital mammography equipment and evaluate usefulness of DBT through compare the image quality of FFDM and DBT. We use mammography equipment, Selenia Dimensions ; this is able to examine breast by both FFDM and DBT, The results are that when the thickness of phantom is 6cm or more and density is 70% or more and the thickness of phantom is 7cm or more and density is 50% or more, AGD of DBT is lower than that of FFDM. The evaluation results of image quality are that in the tumor and small calcification group that composed by mammary tissue and fat, FFDM is great and in fibrin, DBT is great. But in the all thicknesses of BR3D phantom that reflected overlapped tissue of breasts, DBT is great in calcification group, fibrin and tumor. DBT is greater image quality and lower dose more than FFDM in Thick and high density breast, Therefore, DBT is more useful in Korean women's breast that is characterized dense breast than FFDM.

• Economic and Environmental Geology
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• v.54 no.1
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• pp.21-33
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• 2021

The purpose of this study is to determine the order of priority for the use of amendments, matching the optimal amendment to the specific site in Korea. This decision-making process must prioritize the stabilization and economic efficiency of amendment for heavy metals and metalloid based on domestic site contamination scenarios. For this study, total 5 domestic heavy metal contaminated sites were selected based on different pollution scenarios and 13 amendments, which were previously studied as the soil stabilizer. Batch extraction experiments were performed to quantify the stabilization efficiency for 8 heavy metals (including As and Hg) for 5 soil samples, representing 5 different pollution scenarios. For each amendment, the analyses using XRD and XRF to identify their properties, the toxicity characteristics leaching procedure (TCLP) test, and the synthetic precipitation leaching procedure (SPLP) test were also conducted to evaluate the leaching safety in applied site. From results of batch experiments, the amendments showing > 20% extraction lowering efficiency for each heavy metal (metalloid) was selected and the top 5 ranked amendments were determined at different amount of amendment and on different extraction time conditions. For each amendment, the total number of times ranked in the top 5 was counted, prioritizing the feasible amendment for specific domestic contaminated sites in Korea. Mine drainage treatment sludge, iron oxide, calcium oxide, calcium hydroxide, calcite, iron sulfide, biochar showed high extraction decreasing efficiency for heavy metals in descending order. When the economic efficiency for these amendments was analyzed, mine drainage treatment sludge, limestone, steel making slag, calcium oxide, calcium hydroxide were determined as the priority amendment for the Korean field application in descending order.

• Journal of the Korean association of regional geographers
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• v.10 no.4
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• pp.851-864
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• 2004

A coastal dune field, located at Kimnyong-Wolchung beach in Jejudo, Korea, extends alongshore for about 4 km, with dunes extending inland about 6 km. Detailed geomorphological analysis of the area was carried out by using areal photography and Landsat images. Samples were collected across two transects, and physical and chemical properties are analyzed to detect the variation of both properties depending on distance form the beach. Paleosol layers found during the field trip suggest that dune emplacement is episodic. Radiocarbon dates from nearby Hyupjae beach indicate that dunes have been formed during the late Holocene by the disturbance of calcareous materials.

• Nuclear Engineering and Technology
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• v.24 no.3
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• pp.219-227
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• 1992

An experiment was conducted to determine the reaction of boric acid with lime and the drying of its product using a reactor-dryer. no characteristics of dried products were observed. The major chemical species of dried Products was calcium borate of 2CaO.B$_2$O$_3$. From the particle size distribution of the dried products, it was found that quick lime was better than slaked lime as an additive. The Ca/B mole ratio of reaction was determined to be 3/4 considering the cohesion and agglomeration properties of dried products. The flowability of dried products up to 8 wt% of water content was acceptable for transport process and to reduce drying time.

• Explosives and Blasting
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• v.25 no.2
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• pp.61-70
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• 2007

Korean large limestone mines started to employ bulk emulsion explosives to improve the productivity in early 2000s. As the application of the bulk emulsion explosives became common in the mid 2000s, the bulk emulsion application increases overall performance but it tends to decrease the moving and heaving because it lacks in gas volume and heat energy. Therefore, the chemical gassing technique was introduced to improve the blasting efficiency of the existing bulk emulsion explosives. The chemical gassing is a technique to replacing GMB(Glass Micro Balloon), which is used for a sensitizer, with gassing agent to chemically sensitize it. This paper introduces the case of successful application of chemical gassing in a Korean large limestone mine. We also compared and evaluated the blast and work efficiency between bulk emulsion GMB & gassing agent (chemical gassing). The results indicate that the replacement of GMB with gassing agent improved fragmentation in the upper part and toe of a bench as well as moving efficiency of the material.

• Journal of Radiation Protection and Research
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• v.20 no.4
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• pp.245-253
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• 1995

The effects of a simultaneous application of KCl and lime on the root uptake of $^{54}Mn,\;^{60}Co,\;^{85}Sr\;and\;^{137}Cs$ by rice, soybean, Chinese cabbage and radish were investigated through 2 years' greenhouse experiments. At their early growth stages, a mixed solution of the radionuclides was applied to the water or soil surfaces of the culture boxes filled with an acidic loamy-sandy soil for the upper 20cm and $83g/m^2$ of fertilizer KCl and $200g/m^2$ of slake lime were applied to the surfaces. Distribution of radioactivities among plant parts and change in uptake pattern with plant species were not, on the whole, significantly affected by the application. It reduced effectively soil-to-plant transfer factors of $^{85}Sr\;and\;^{137}Cs$ for rice, of all for Chinese cabbage and of $^{54}Mn,\;^{60}Co,\;and\;^{137}Cs$ for radish without their growth inhibition. In rice, $^{85}Sr$ showed the highest decrease $({\sim}60%)$ while, in Chinese cabbage and radish, $^{54}Mn$ did $({\sim}80%)$. The exprimental results can become valuable reference data to establish countermeasures against a radioactive contamination of farm-land during plant growth.