• Journal of Korean Society of Forest Science
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• v.98 no.6
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• pp.676-680
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• 2009

The study was conducted to investigate the characteristics of growth and fruiting in chestnut trees by SCB (Slurry Compostion and Biofilteration) liquid fertilizer instead of Chemical fertilizer. The experiment was done between April, 2008 and September, 2009, using seven years old grafting trees 'Tsukuba'. Fertilizer treatment was designed as follows; SCB liquid fertilizer, chemical fertilizer, organic fertilizers and no fertilized. Results were as follows; In the 2nd year, height and basal diameter gain of 8.04% and 25.90% over than the 1st year by SCB liquid fertilizer. The number of burrs per bearing mother branch showed no significant increment by SCB liquid fertilizer but fruiting rate was higher than other treatments. These results indicated that the SCB liquid fertilizer has a value of new eco-friendly fertilizer.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.29 no.6
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• pp.513-519
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• 2016

In this study, dynamic vertical displacement of liquid in the tuned liquid column damper(TLCD) is measured by a laser Doppler vibrometer(LDV) to overcome limitations of existing sensors and to leverage noncontact sensing. Addressing advantages of noncontact measurements, operational principles of the LDV to measure velocity and displacement of a target object in motion is explained. The feasibility of application of the LDV to measurement of liquid motion in the TLCD is experimentally explored. A series of shake table tests with the TLCD are performed to determine requirements of application of the LDV. Based on the experimental results, it is proved that the LDV works under the condition of adding dye to the liquid by increasing the intensity of reflected laser and thus validity is verified by comparison with a conventional wave height meter.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.6
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• pp.945-953
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• 2010

This study was conducted to evaluate the effect of swine liquid manure (SLM) on rice grown in Yeonggwang-gun in 2008. The treatments consisted of SLM and chemical fertilizer (CF) based on the recommended amount of nitrogen (11 kg N $10a^{-1}$). The Total N content of the SLM used was 2,881 mg $L^{-1}$. Plant height at the early stage of growth and tiller number were not significantly different between plots applied with swine liquid manure and those with chemical fertilizer in all areas. Plant height at the later stage of growth, lodging and yield were not significantly different between plots applied with swine liquid manure and those with chemical fertilizer in three areas (Baeksu, Gunnam, Beopseong). Plant height at the later stage of growth, as well as lodging were higher in SLM plots than in chemically fertilized plots in Yeonggwang and Yeomsan. However, grain yield was lower in SLM plots than in chemically fertilized plots in these areas. Soil organic matter content and exchangeable cations increased in the swine liquid manure applied plots. Moreover, heavy metal content did not increase in the plots treated with swine liquid manure. Further research to determine the suitable rate of swine liquid manure is needed to reduce lodging damage and to increase the yield and quality of rice.

• Korean Chemical Engineering Research
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• v.58 no.4
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• pp.665-674
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• 2020

Low-frequency pressure fluctuations in an external-loop airlift reactor were investigated. Low-frequency pressure fluctuations could be measured by shooting videos about liquid levels in the four piezometric tubes which were installed at the lower and upper parts of the riser and downcomer using a cellular phone. The periodic characteristics of pressure fluctuations were proved by the calculation of their auto-correlation function and cross-correlation function. Even if the riser superficial gas velocity was constant, the riser and downcomer gas holdups as well as wall pressures were periodically changed due to the inertia of circulating liquid. In general, the intensity of pressure fluctuations increased with an increase in the gas velocity. When the unaerated liquid height was 0.04 m, the maximum period of pressure fluctuations was found at the specific gas velocity (0.14 ms^-1). It was because the maximum inertia of circulating liquid resulted from a reduction in the increasing rate of the liquid circulation velocity and a decrease in the volume of the effectively circulating liquid with an increase in the gas velocity.

• Korean Chemical Engineering Research
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• v.54 no.4
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• pp.543-547
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• 2016

Bubble properties such as size (chord length) and rising velocity were investigated in a bubble column with electrolyte solutions, of which diameter was 0.152m and 2.5m in height, respectively. The size and rising velocity of bubbles were measured by using the dual electrical resistivity probe method. Effects of gas and liquid velocities and ionic strength of liquid phase on the size and rising velocity of bubbles were determined. The bubble size increased with increasing gas velocity but decreased with increasing liquid velocity or ionic strength of liquid phase. The rising velocity of bubbles increased with increasing gas velocity and decreased with increasing ionic strength of liquid phase, however, it showed a slight maximum value with varying liquid velocity. The size and rising velocity of bubbles were well correlated with operating variables.

• Applied Chemistry for Engineering
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• v.8 no.5
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• pp.816-821
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• 1997

The hydrodynamics and the liquid flow characteristics were investigated in an internal circulation airlift reactor with a single nozzle as a gas distributor. In an air-water system, the gas holdup in the individual flow zone and the impulse-response curve of tracer were measured at various gas velocities and reactor heights. Experimental results showed that for the higher gas velocity(>about 8 cm/s), the flow behavior of bubbles in the riser was turbulent flow due to strong bubble coalescences and the axial height of dispersion zone of large bubbles having uniform sizes in the downcomer was decreased with increasing gas velocity. And mean gas holdups in the individual flow zone and the reactor were increased with increasing gas velocities and were decreased with increasing heights of the top section of the reactor and it was decreased with increasing the height of the top section and gas velocity. Flow characteristics of liquid in the riser and the downcomer was tend to access to plug flow and the overall flow behavior of liquid was mainly varied with the size of the top section which it was assumed to be perfect mixing zone. In these conditions, liquid circulation velocities were increased with increasing gas velocities and they were higher than those by using other gas distributors.

• Nuclear Engineering and Technology
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• v.52 no.6
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• pp.1172-1179
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• 2020

As a Lagrangian particle method, Moving Particle Semi-implicit (MPS) method has great capability to capture interface/surface. In recent years, the multiphase flow simulation using MPS method has become one of the important directions of its developments. In this study, some key methods for multiphase flow have been introduced. The interface tension model in multiphase flow is modified to maintain the smooth of the interface and suitable for the three-phase flow. The mass transfer at immiscible liquid interface entrained by single bubble which could occur in Molten Core-Concrete Interaction (MCCI) has been investigated using this particle method. With the increase of bubble size, the height of entrainment column also increases, but the time of film rupture is slightly different. With the increase of density ratio between the two liquids, the height of entrained column decreases significantly due to the decreasing buoyancy of the denser liquid in the lighter liquid. In addition, the larger the interface tension coefficient is, the more rapidly the entrained denser liquid falls. This study validates that the MPS method has shown great performance for multiphase flow simulation. Besides, the influence of physical parameters on the mass transfer at immiscible interface has also been investigated in this study.

• Korean Journal of Organic Agriculture
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• v.22 no.2
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• pp.293-302
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• 2014

As part of the agricultural natural circulation, the present study was performed. Recently, there has been the movement toward reusing the Liquid Pig Manure as an alternative fertilizer sources for agricultural lands. For instance, LPM (Liquid Pig Manure) liquid fertilizer has been developed and widely used in Korea. However, the impacts of LPM on both agricultural environment and crop triticale yield have not been investigated yet. The experiments were studied on paddy field after treatment of LPM on plant height, root length, plant length, dry matter yield and soil chemical properties. The effect of LPM by application on triticale was more increased plant height, root length and plant length than the Control. Chemical soil characteristics were not significantly different between on Control and LPM. Soil pH, OM, TN, $P_2O_5$ and exchangeable cation of triticale (X Triticosecale wittmack) appeared to be lower than before the treatment. Dry matter yield were produced 834.3kg $10a^{-1}$ of in LPM plot and 684.4kg $10a^{-1}$ in Control plot. In these results show abbreviated as the application of LPM increases the yield index of triticale. However, the properties of paddy soil were not affected by the LPM application.

• Journal of Animal Environmental Science
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• v.13 no.1
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• pp.53-58
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• 2007

This study was carried out to determine the effect of continuous application of animal liquid slurry on the growth and yield of rice in 2005. Field experiment was conducted under variable continuous application years of animal liquid slurry; 1, 3, 5 application years of slurry and chemical fertilizer as control plot. The effects of different application years of slurry on the growth characteristics and yield of rice were determined. The plant height and tiller's number of 1 year application of liquid slurry were lower than those of the chemical fertilizer plot. But in the plot of 5 years continuous application of animal slurry, the height and tillers of rice were higher than those of 1 year application. And the color of leaf 5 years application years plot was darker than that of the chemical fertilizer. Yield of the 5 years continuous application of slurry was 4% higher than that chemical fertilizer, but that of 1 year application was decreased 6% compared with chemical fertilizer. The long time application of animal slurry was increased content of organic matter, $P_2O_5$ and exchangeable caution(K) in soil.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.5
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• pp.805-809
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• 2012

To evaluate the effects of liquid pig manure (LPM) on green manure crop yields, plant height and biomass of green manure crops were investigated in single and companion cropping. Green manure crops used for this experiment were Hordeum vulgare L. (green barley) and Vicia villosa roth (hairy vetch). Field experiment was designed with LPM 1.65 (LPM of $1.65ton\;10a^{-1}$ + single and companion green crops), LPM 3.3 (LPM of $3.3ton\;10a^{-1}$ + single and companion green crops) and LPM 6.6 (LPM of 6.6$6.6ton\;10a^{-1}$ + single and companion green crops). In single cropping, plant height were high in LPM 3.3. In companion cropping, plant height were high in LPM 6.6. Thus, we found that application of LPM is general enough to reduce use of chemical fertilizer. Also, optimum application level in single cropping would be LPM 3.3 and in companion cropping would be higher than LPM 3.3.