• Korean Journal of Soil Science and Fertilizer
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• v.30 no.3
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• pp.248-256
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• 1997

In order to establish a optimum level and proper method of fly ash application for soybean cultivation, the successive three years experiment was conducted in the field applied with four application levels of fly ash, 0, 30, 60, 90 MT/ha during the 1991 to 1993. Influence of successive application and residue of fly ash in soil on soybean growth and yield was discussed. Fly ash application had a favorable effect on soybean growth, however over application such as 90 MT/ha caused to turn the color into the brown of young leaf edge and eventually to have necrosis on the leaf. This symptom was prominent under the application of bituminous coal fly ash. In the 1st year cultivation of soybean, the highest yield was obtained at application level of 30 MT/ha. In the 2nd year, application of anthracite fly ash showed the highest yield at 60 MT/ha for successive application and at 90 MT/ha for the 1st year application followed by the 2nd year residue. Application of bituminous coal fly ash showed the highest yield at 60 MT/ha for the both successive application and residue. In the 3rd year, successive application of the both fly ash was given the highest yield at 30 MT/ha, respectively indicating the decrease of yield with increasing level of application. In case of residue plot, the highest yield by the application of anthracite fly ash was made at 90 MT/ha for the 1st year application followed by 2 years residue and at 60 MT/ha for the 1st and 2nd year application followed by the 3rd year residue. But in the residue plot of bituminous coal fly ash, yield was highest at 30 MT/ha showing the decrease of yield with increasing level of residue. Enhancement in growth and yield of soybean by application of fly ash was due to the fact that fly ash contained some plant nutrients such as phosphorus, silicon, and boron etc. and reformed soil pH that caused to increase availability of nutrients in soil.

• Journal of Korea Water Resources Association
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• v.41 no.7
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• pp.681-692
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• 2008

This study investigated the application of the successive correction method(SCM), a simple data assimilation method, for synthesizing the radar and rain gauge data. First, the number of iteration and influence radius for the SCM application were decided based on their sensitivity analysis. Also, for the evaluation of synthetic rainfall, the distributed rainfall field using the dense rainfall gauge network was assumed to be the true one. The synthetic rainfall field based on the SCM was also compared quantitatively with the one based on the co-Kriging frequently used nowadays. As the results, the SCM, a simple and economical data assimilation method, was found to secure the accuracy and statistical characteristics of the co-Kriging application.

• Structural Engineering and Mechanics
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• v.53 no.6
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• pp.1167-1182
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• 2015

In this study, the stresses and electric potential redistributions of a cylinder made from functionally graded piezoelectric material (FGPM) are investigated. All the mechanical, thermal and piezoelectric properties are modeled as power-law distribution of volume fraction. Using the coupled electro-thermo-mechanical relations, strain-displacement relations, Maxwell and equilibrium equations are obtained including the time dependent creep strains. Creep strains are time, temperature and stress dependent, the closed form solution cannot be found for this constitutive differential equation. A semi-analytical method in conjunction with the Mendelson method of successive approximation is therefore proposed for this analysis. Similar to the radial stress histories, electric potentials increase with time, because the latter is induced by the former during creep deformation of the cylinder, justifying industrial application of such a material as efficient actuators and sensors.

• Korean Journal of Materials Research
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• v.34 no.2
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• pp.79-84
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• 2024

Thin films of yttria-stabilized zirconia (YSZ) nanoparticles were prepared using a low-temperature deposition and crystallization process involving successive ionic layer adsorption and reaction (SILAR) or SILAR-Air spray Plus (SILAR-A+) methods, coupled with hydrothermal (175 ℃) and furnace (500 ℃) post-annealing. The annealed YSZ films resulted in crystalline products, and their phases of monoclinic, tetragonal, and cubic were categorized through X-ray diffraction analysis. The morphologies of the as-prepared films, fabricated by SILAR and SILAR-A+ processes, including hydrothermal dehydration and annealing, were characterized by the degree of surface cracking using scanning electron microscopy images. Additionally, the thicknesses of the YSZ thin films were compared by removing diffusion layers such as spectator anions and water accumulated during the air spray plus process. Crack-free YSZ thin films were successfully fabricated on glass substrates using the SILAR-A+ method, followed by hydrothermal and furnace annealing, making them suitable for application in solid oxide fuel cells.

• Journal of the korean academy of Pediatric Dentistry
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• v.8 no.1
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• pp.55-63
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• 1981

The purpose of this study is to observe the effect of formocresol and glutaraldehyde to tooth germs and periapical tissues after perforation of interradicular portion of pulpal floor and application of physiological saline solution in control groups, formocresol and glutaraldehyde in experimental groups. The following results were obtained 1. In control groups, normal healing processes were seen, and, on the sixteenth day, the epithelization of injured areas was completed. Inflammatory reactions were limited to the injured surface, and the underlying alveolar bone were normal and successive tooth germs were normal. 2. In both formocresol groups and glutaraldehyde groups, tissue reactions were identical. Inflammatory reactions were slightly compared with control groups, but the surface epithelizations were delayed compared with control group. 3. In both formocresol and glutaraldehyde groups, necrosis was seen in superficial tissue of bone marrow, and, at 24th day, center area of bone marrow on the successive tooth germs were losed and replaced with connective tissue, and superficial soft tissue of the injured area was connected with soft tissue on the successive tooth germ. In remaining alveolar bone, osteoclastic reaction was remarkable. 4. In both formocresol and glutaraldehyde groups, there is no injury to the successive tooth germs. 5. In both formocresol and glutaraldehyde groups, periodontal membrane was normal, but the partial resorption of cementum and dentin near the injured area were seen.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.20 no.6
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• pp.553-563
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• 2008

If an arbitrary topography is approximated to a number of vertical steps, both variational approximation and eigenfunction expansion method can be used to compute linear wave transformation over the bottom. In this study a scatterer method associated with variational approximation is proposed to calculate reflection and transmission coefficients. Present method may be shown to be more simple and direct than the successive-application-matrix method by O'Hare and Davies. And Several numerical examples are given which are in good agreement with existing results.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.4
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• pp.431-438
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• 1983

Experiments were conducted to know the effects of 15 years successive application of fertilizers and organic matters on the soil properties, plant growth and yield of rice. Application of fertilizers and organic matters for 15 years in same plots were increased soil pH, OM, and CEC, but decreased $SiO_2$ and Ca content in paddy soil. Organic matter application for 15 years was increased OM about 0.5% compare to non-applied plot. Particulary lime application was increased soil pH, $SiO_2$, Ca and CEC in paddy soil. NPK+compost and NPK+straw application were increased number of panicles and number of spikelets per unit area, but decreased ripening ratio compare to NPK applied plot. Average grain yield for 15 years in the non-fertilized, -N, -P, -K, NPK+compost, NPK+straw and NPK+lime applied plot was 47, 51, 88, 95, 113, 117, and 106% of yield conpare to NPK applied plot, respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.4
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• pp.287-292
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• 1981

The field studies were carried out in paddy field over a four year period in order to find out the effects of butachlor, nitrofen, oxadiazon or CG 102, benthiocarb-S, and bentazon applied successively to the same paddy field for four years on weed succession and rice yields under different fertilized conditions including compost, chemical fertilizer and straw application. Total dry weight of weeds was steadily increased yearly over 4 year period regardless of fertilized conditions, and significantly higher increase of weed dry weight was observed on non-fertilized and compost plots. The most dominant weed species was Scirpus hotarui, and Potamogeton distinctus, Eleocharis kuroguwai and Cyperus serotinus were predominated on compost plot, E. kuroguwai and E. aclularis on non-fertilized plot, E. kuroguwai, C. serotinus, and Monochoria vaginalis on chemical fertifizer plot, and C. serotinus on straw plot. When the same herbicides were used continuously on the same plots, weed control effect was decreased and thus weed population was greatly increased particularly on butachlor and nitrofen treated plots. P. distinctus, E. kuroguwai, and C. serotinus were predominated on butachlor treated plot, P. distinctus and C. serotinus on nitrofen treated plot, C. serotinus on benthiocarb-S treated plot, C. serotinus and P. distinctus on oxadiazon or CG 102 treated plot and P. distinctus on bentazon treated plot. Annual weeds were slightly increased by repeated annual application of oxadiazon or CG 102 and benthiocarb-S, whereas perennial weeds were predominated by successive application of butachlor, nitrofen. and bentazon for 4 years. Yield reduction of rice became prominent by successive application of same herbicides. particularly butachlor and nitrafen. This results suggested that successive annual application of same herbicides should be limited and herbicide combination or herbicide rotation should be applied to control the remaining weed species.

• Korean Journal of Soil Science and Fertilizer
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• v.27 no.2
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• pp.72-77
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• 1994

This study was conducted to investigate the influence of treatment of fly ash on heavy metal contents of the arable soil. Rice was cultivated on the two types of paddy field clay loam and sandy loam with 0, 12ton/10a of anthracite fly ash and bituminous coal fly ash application. And soybean was cultivated at the same type of upland fields with those ashes of 0, 9ton/10a, yearly for three years. At the harvest time, the heavy metal contents in the different layer were investigated. The results were summarized as follows : 1. The contents of some heavy metal were increased in the surface soils but didn't show the tendency in the deeper layer or soil texture. 2. In the paddy fields, the contents of Cd, Cu, Zn, Cr were increased. Meanwhile and the upland fields, the contents of Cd and Cr were increased with the successive application of Anthracite fly ash, but the others didn't show those tendency. 3. The contents of Cd, Cu and Zn in the paddy field, were increased but the upland field, the contents of Cd, Cr and Ni were increased by the successive application of bituminous coal fly ash.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.4
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• pp.545-550
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• 2011

Urea intercalated into montmorillonite (MT) exhibits remarkably enhanced N use efficiency, maintaining its fast effectiveness. This study dealt with the release property of urea from metal-urea-clay hybrid with MT (MUCH) under continuous-flow conditions and the cumulative impacts of its successive application on physicochemical properties of soils. Releases of urea were completed within 4 hrs under continuous-flow condition regardless of the types and the leaching solutions. However, urea release property was significantly affected by both the form of fertilizer and the presence of electrolytes in solution. The fast release property of urea from MUCH in continuous-flow condition was not significantly affected by soil properties such as soil pH and soil texture. In addition, its successive application did not lead to any noticeable change in soil physicochemical properties, water stable aggregate rate, water holding capacity and cation exchange capacity in both sandy loam and clay loam soils. Therefore, this study strongly supported that urea intercalated into MT could be applied as fast-effective N fertilizer, in particular for additional N supply.