• 한국축산시설환경학회지
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• 제13권2호
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• pp.139-146
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• 2007

본 연구는 가축액상분뇨의 비료성분 불균형을 화학비료로 조정하여 작물양분의 최적화에 의한 벼의 생육과 품질향상을 검토하기 위하여 수행되었다. 양돈분뇨발효액비와 화학비료를 혼합하여 조제한 맞춤비료(LCSC)의 시용이 벼의 생육특성, 수량, 수량구성요소, 쌀 품질에 미치는 영향을 조사하였다. 처리구는 맞춤비료(LCSC) 기비 50% + 화학비료 50% 추비구, LCSC 기비 75% + 화학비료 25% 시용구, 100% LCSC 시용구, 100% 양돈 분뇨발효액비 시용구(LM)를 두었다. 또한 대조구로 화학비료 시용구를 두었다. 1. 초장은 생육초기에 화학비료 시용구와 LCSC와 화학비료 혼합 시용구에서 가장 큰 것으로 나타났다. 생육후기의 초장은 LM 시용구가 가장 적었다. 분얼수의 경우도 화학비료 시용구와 LCSC 시용구가 LM 시용구 보다 더 많았다. 엽록소 함량은 생육초기 화학비료 및 LCSC 시용구에서 LM 시용구 보다 높았으나 생육후기에는 LM 처리구와 LCSC 100% 처리구 사이에 유의한 차이가 없었다. 2. 수량구성요소에 있어서 주당수수는 화학비료구와 LCSC 기비 + 화학비료 추비 시용구에서 가장 많은 것으로 나타났다. 수당립수는 화학비료 시용구에서 가장 많았으나 처리간에 유의한 차이를 나타내지 않았다. 천립중과 등숙률은 처리구 사이에 유의한 차이를 나타내지 않았다. 3. 벼의 정조수량은 LCSC + 화학비료 혼합 시용구에서 681 kg/10a로서 가장 높았다. LCSC 100% 기비시용구의 정조수량은 화학비료 대비 9% 감수되었으며, LM 시용구는 화학비료 시용구 대비 7% 감수되었다. 4. 현미의 미질은 LM 시용구와 LCSC 100% 기비 시용구에서 화학비료 시용구에 비하여 유의성 있게 높게 나타났다. 현미의 단백질 함량은 화학비료 시용구에서 LM 시용구와 LCSC 100% 기비 시용구보다 유의성 있게 높았다. 따라서 쌀 품질향상에 적절한 양의 LCSC와 화학비료 혼합시용이 효과가 있는 것으로 나타났다.

• 한국유기농업학회지
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• 제24권2호
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• pp.221-234
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• 2016

본 연구는 벼에 돈분액비와 화학비료를 연용하여 살포하였을 때 돈분액비가 벼의 수량과 미질 및 토양 화학성에 미치는 영향을 구명하고자 2012년부터 3년간 수행하였다. 시험은 강원도 철원군 농가 포장에서 오대벼를 공시하여 실시하였다. 시비는 돈분액비를 질소 검정시비량을 기준으로 하여 100%에 해당하는 양을 처리하였으며, 화학비료 처리구와 비교하였다. 돈분액비의 시용년수에 따른 벼의 분얼수 및 초장은 돈분액비 1년 시용구와 화학비료 사이에 유의한 차이를 나타내지 않았다. 돈분액비 3년 시용구의 분얼수는 화학비료 시용구보다 많았다. 쌀의 수량은 돈분액비 1년 시용구가 화학비료 대비 7% 감소하였다. 그러나 돈분액비 3년 연속 시용구에서 $495kg\;10a^{-1}$의 수량을 얻어 화학비료 대비 8% 증수하였다. 돈분액비로 벼를 3년 재배하였을 때 쌀의 단백질 함량은 7.01%로 대조구인 화학비료 시용구 보다 높은 수준이었다. 아밀로스 함량은 15.5~17.0%로 처리구별 유의성은 없었다. 식미치를 Toyo 식미계를 이용하여 조사한 결과 돈분액비 100% 처리구의 식미치가 65.3%로 화학비료 시용구보다 낮은 수준이었다. 쌀의 품위 특성에서 돈분액비 100% 처리구의 완전미 비율은 78.7%로 낮았으며, 불완전미의 비율을 높인 주 원인은 분상질립, 피해립의 비율이 높았기 때문이었다. 3년간 돈분 액비를 계속 사용한 결과, 화학비료 처리에 비해 토양 중 칼륨과 아연의 함량이 높았으나 다른 중금속 함량도 관행 화학비료 처리와 크게 다르지 않았다. 이상의 결과를 미루어 볼 때 돈분액비의 3년 시용시 돈분 액비의 연용이 쌀의 수량성에 나쁜 영향을 미치지는 않을 것으로 판단되지만 쌀의 단백질 함량이 증가하고 Toyo 식미치와 완전미 비율은 감소하는 결과를 얻었다. 돈분액비 3년 시용 후 토양의 칼륨 축적이 되므로 토양검정에 의한 액비 적량시용이 요구된다.

• 한국안전학회지
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• 제19권3호
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• pp.45-50
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• 2004

4-panel of 1m height and 45cm width were fixed on the $40cm{\times}40cm$ bottom plate and the opening of the panel comer was 5cm. Diameter of stainless vessel is loom and its height is 2cm and it located at the center of the bottom plate. 78mL liquid fuel was filled in the vessel and its depth was 1cm. Flame temperature was measured with K type thermocouple, and radiation heat of flame was measured with heat flux meter. Flame height and its behavior was visualized with video camera. and mass burning rate was measured by fuel combustion time. According to the development of fire, flame swirling was begin. From the experiment the mass burning rate was larger and the height of flame was higher than the usual pool fire flame. Flame temperature and heat flux also increased far more than the pool fire. Consequently the swirling air flow through the openings between the panel and thermal buoyance contribute to increase of heat release rate, flame length and mass burning rate.

• 한국지하수토양환경학회지:지하수토양환경
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• 제25권3호
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• pp.23-31
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• 2020

The performance of a downward-irradiation sonoreactor was investigated using calorimetry, KI dosimetry, luminol (Sonochemiluminescence, SCL) method, and aluminium foil erosion method as one of the basic steps for the optimal design of downward-irradiation sonoreactors. The applied frequency was 28 kHz and the input electrical power was 280 - 300 W. The liquid height, from the reactor bottom to the transducer module surface, ranged from 1λ (53.6 mm) to 2λ (107.1 mm). For various liquid heights, the magnitude of calorimetric power and the mass of cavitation-generated I₃^- ion varied significantly. It was found that the additional application of mechanical mixing resulted in higher sonochemical activity, especially in the cavitational active zone, which was induced by violent liquid flow in the reactor. In aluminium foil erosion tests, it was found that less ultrasound energy reached the bottom of the reactor due to the violent liquid flow and no significant sonophysical effect was observed for higher mixing rate conditions (100 and 200 rpm).

• 한국응용과학기술학회지
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• 제19권4호
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• pp.251-257
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• 2002

Liquid-phase methanol synthesis via methyl formate using coal-derived syngas was carried out in a bench-scale(diameter 173 mm and dispersion height 1200 mm) slurry bubble column reactor(SBCR) Under the condition of $180^{\circ}$. 61 atm, 30 L/min, $H_{2}$/CO=2 and a slurry mixture of 2 kg of copper chromite and 0.5 kg of $KOCH_{3}$ suspended in 14 L of methanol, the per pass conversions of syngas is 6 %, maximum concentration of methyl formate 3.088 mol% and maximum synthesis, rate of methanol 0.8 gmole/kg ${\cdot}$ hr. It is a significant evidence that copper chromite powder as heterogeneous catalyst didn't active for the hydrogenolysis of methyl formate to methanol, resulting copper chromite powder was not efficiently suspended in a slurry mixture. To enhance the hydrogenolysis of methyl formate in liquid-phase methanol synthesis process, the designed SBCR have need to use the higher specific gravity solvent and/or decrease the catalyst particle size.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2009년도 하계학술발표대회 논문집
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• pp.1220-1225
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• 2009

A manipulator is operated for the motion of mechanical hands or arms. When a cup including liquid inside is shifted by a manipulator, it is important to know how a free surface of the liquid moves. In this study, non dimensional parameters have been found that affect the rise of the free surface in a cup moving with constant acceleration. The non-dimensional parameters are the dimensionless time, the ratio of inertia effect to viscous effect (the Reynolds number), aspect ratio of the liquid inside the cup and the acceleration ratio (the Froude number). Through this study, the height of the free surface rise in a cup has been predicted and the detailed velocities in the liquid have been examined. Generally, the maximum rise of the free surface is dependent on the Reynolds number and Froude number strongly, but on the aspect ratio weakly. However, the influence of the aspect ratio on the maximum rise of the free surface is not negligible in the range of 10 < Re < 100.

• 한국소음진동공학회논문집
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• 제19권9호
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• pp.950-959
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• 2009

Liquid fluctuation called sloshing within liquid-storage tank gives rise to the significant effect on the dynamic stability of tank. This liquid sloshing can be effectively suppressed by installing baffles within the tank, and the suppression effect depends strongly on the design parameters of baffle like the baffle configuration. The present study is concerned with the parametric evaluation of the sloshing suppression effect for the CNG-storage tank, a next generation liquefied fuel for vehicles, to the major design parameters of baffle, such as the baffle configuration, the installation angle and height, the hole size of baffle. The coupled FEM-FVM analysis was employed to effectively reflect the interaction between the interior liquid flow and the tank elastic deformation.

• 공업화학
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• 제17권5호
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• pp.509-516
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• 2006

Rushton turbine, paddle and propeller 임펠러 등 표준적인 임펠러가 부착된 기-액-고 3상교반조에서 고-액간 물질이동계수 $k_L$를 측정하였다. 표준적인 임펠러들에 대한 부유화한계회전수 $N_{js}$는 임펠러 높이와 가스유속에 따라 변했다. 입자부유가 통기에 의존한 Rushton turbine 임펠러의 물질이동계수는 Pgv에만 상관하였다. Rushton turbine, paddle and propeller 임펠러에 대한 물질이동계수 $k_L$은 임펠러의 종류에 의하지 않고 임펠러 위치에 영향을 받았다.

• Journal of Advanced Marine Engineering and Technology
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• 제25권4호
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• pp.797-808
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• 2001

Three-dimensional trajectory of fluid particle is simulated by a particle motion, which is able to examine the influences of changes in the several parameters. To calculate the trajectory of a particle, the Runge-Kutta method was utilized. The use of a projectile of particles for the trajectory of liquid jet has been shown to be useful to estimate the influence of different operating parameters such as best particle diameter, density of liquid body, initial take-off velocity, wind velocity, cross wind velocity, take-off angle, and base angle for a released flow from the nozzle. The results give the trajectories of various types of particle of body and at different elevations, base angles, wind velocities and densities of liquid body. The trajectories in a vacuum show that air resistances decreases both the distance and the maximum height of a projectile, and also explain that the termination time is also reduced in air. In addition, the maximum distance in the x direction was obtained with take-off angles from 30 degrees to 45 degrees in still air and the projectile of particles was highly effected by wind and cross wind. Clearly, a particle has to be so positioned as to take the optimum possible advantage of the wind if the maximum distances is requested. The wind astern increased the maximum distances of x direction compared with the wind ahead. Finally, it is possible to optimize the design of pump by using these results.

• 한국연소학회지
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• 제18권2호
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• pp.17-22
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• 2013

In this study, we tested the absorption of $CO_2$ in combustion gas into an alkaline wastewater to simultaneously control $CO_2$ and wastewater. During the experiment, we investigated the effects of operating parameters on neutralization characteristics of the wastewater by using $CO_2$ in a bench-scale semi-batch jet loop reactor (0.1 m diameter and 1.0 m in height). The operating parameters investigated in the study are gas flow rate of 1.0-2.0 L/min, liquid recirculation flow rate of 4-32 L/min, and liquid temperature of $20-25^{\circ}C$. It was shown that the initial pH of wastewater rapidly decreased with increased gas flow rate for a given liquid recirculation flow rate. This was due to the increase in the gas holdup and the interfacial area at higher gas flow rate in the reactor. At constant gas flow rate, the time required to neutralize the wastewater initial pH of 10.1 decreased with liquid recirculation flow rate ($Q_L$), reached a minimum value in the range of $Q_L$ = 16-24 L/min, and then increased with further increase in $Q_L$. Further, the time required to neutralize the wastewater was shortened at higher temperatures.