• Journal of Korean Society for Atmospheric Environment
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• v.16 no.2
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• pp.165-178
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• 2000

In this study the effects of block distance have been investigated on the particle deposition efficiency in the collecting cell of two-stage electrostatic precipitator by numerical analysis. Particle trajectories have been changed by the electrostatic and inertial force of particle with the inlet velocity electrostatic number and particle diameter. The total deposition efficiency has a minimum value by the interaction between the effect of particle inertial force and electrostatic force in the collecting cell. The increase of block distance makes the total deposition efficiency decrease under the range of the particle size which has the minimum deposition efficiency. However beyond the range of particle size which has minimum deposition efficiency total deposition efficiency has no trend with the variation of block distance.

• Journal of the Korean Society for Heat Treatment
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• v.3 no.1
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• pp.1-7
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• 1990

To investigate the influence of r.f. power and electrode distance on the TiN deposition, TiN films were deposited onto STC3, STD11 steel and Si-wafer from gas mixtures of $TiC_4/N_2/H_2$ using the radio frequency plasma assisted chemical vapor deposition. The crystallinity of TiN film could be improved by the increase of r.f. power and the decrease of electrode distance. The TiN coated layer contains chlorine, its content were decreased with increasing r.f. power as well as decreasing electrode distance. And the thickness of deposited TiN was largely affected by r.f. power and electrode distance. The hardness of deposited TiN reached a maximum value of about Hv 2,000.

• Korean Journal of Materials Research
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• v.9 no.2
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• pp.144-148
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• 1999

We have studied the deposition characteristics of thick silicon dioxide film on Si substrate by $O_3$/TEOS APCVD(Atmospheric Pressure Chemical Vapor Deposition). The effect of deposition parameters such as the distance between showerhead and substrate, deposition temperature, TEOS flow rate and $O_3$/TEOS ratio on deposition rate, surface morphology, and properties of films as investigated. As deposition temperature increased, deposition rate decreased but the surface morphology and adhesion of film to substrate improved. As the distance between showerhead and substrate decreased, the deposition rate increased. Etching rate using the BOE increased as TEOS flow rate increased, but was independent of$ O_3$/TEOS ratio. Deposition rate of $5\mu\textrm{m}$/hour was obtained under the condition that the distance between showerhead and substrate was 5mm and the deposition temperature was $370^{\circ}C$.

• Journal of the Korean institute of surface engineering
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• v.23 no.2
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• pp.24-29
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• 1990

The TiN filmms were deposited on the stainless steel substrates by BARE techinique in order to investigate the effects of process parameters such as source-to-substate distance (15-35cm), N2 pressure(4$\times$10-10 -1$\times$10-3mb)and bias voltage(O-2000V), on the deposition rate, the concentration ratio [N/Ti] and the surface color of the films. The deposition rate was deduced from the weight measurement, the [N/ti] ratio by ESCA. The deposition rate decreased with a relationship of=40.2/D2 where D was source-to-substrate distance. The effect of the bias voltage and the N2pressure on the deposition rate, however, appeared negligble. The [N/Ti] ratio was in the narrow range of 0.7 tp 0.8 It increased slightly with the N2 partial pressure and deceased with the source-to-substrate distance. It was confired by ESCA that a significant amount of oxygen and carbon was contaminated after deposition in the top surface of TiN films. The surface color of TiN film was changed from light gold yellow to reddish gold yellow with increasing [N/Ti] ratio.

• Journal of The Korean Society of Agricultural Engineers
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• v.58 no.1
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• pp.11-17
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• 2016

Dredging and land reclamation works has actively carried out for the efficient use of land and secure of agricultural and industrial site. During the reclamation, a portion of landfills are lost from the desired location due to a variety of causes. However, these causes has been rarely studied, and water flow velocity has a great influence on the movement of landfills. For the economical and efficient reclamation, it is important to predict the movement of landfills in water. In this paper, an experimental study was carried out to investigate the deposition distance according to the flow velocity and soil grain size. We have made a large open-channel apparatus that can reproduce a laminar flow, and the deposition test was carried out on the four grain size (0.638, 1.425, 3.375, 7.125 mm) and four flow velocity (0.1, 0.3, 0.5, 0.67 m/s) with high definition video recording. As a results, average deposition distance increased with the flow velocity, and its relationship is shown linearly. For the grain size, the average deposition distance were drastically increased as the grain size becomes smaller.

• Proceedings of the IEEK Conference
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• 2003.07b
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• pp.1049-1052
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• 2003

This study shows the change of the structural characteristic of AIN thin film deposition with the change of the deposition conditions such as Ar/$N_2$ gas ratio, operating pressure in chamber, and the distance between substrate and target in RF Magnetron Sputtering. The orientation and surface roughness of AIN thin film are studied by using XRD and AFM and the thickness is measured by using STYLUS PROFILER. While we can not identify the orientation of the thin film deposited in Ar only, we can obtain the (100) orientation of the thin film with the addition of $N_2$ to Ar. Especially the thin film deposited at 10% of Ar/$N_2$ gas ratio appears to be the most (100) oriented. The (100) orientation of thin film becomes weaker as the operating pressure becomes higher. The further distance between substrate and target is stronger the (100) orientation of the thin film is. The (100) orientation becomes weaker and (002) orientation starts to appear as the distance is shorter.

• Journal of Advanced Marine Engineering and Technology
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• v.32 no.1
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• pp.57-65
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• 2008

The characteristics of soot deposition on the cold wall in laminar diffusion flames have been numerically analyzed with a two-dimension with the FDS (Fire Dynamics Simulator). In particular, the effects of surrounding air temperature and wall temperature have been discussed. The fuel for the flame is an ethylene ($C_2H_4$). The surrounding oxygen concentration is 35%. Surrounding air temperatures are 300K, 600K, 900K and 1200K. Wall temperatures are 300K, 600K and 1200K. The soot deposition length defined as the relative approach distance to the wall per a given axial distance is newly introduced as a parameter to evaluate the soot deposition tendency on the wall. The result shows that soot deposition length is increased with increasing the surrounding air temperatures and with decreasing the wall temperature. And the numerical results led to the conclusion that it is essential to consider the thermophoretic effect for understanding the soot deposition on the cold wall properly.

• Journal of the Korean Geotechnical Society
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• v.29 no.5
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• pp.19-27
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• 2013

Most of the landslides induced by rainfall in summer rainy season appear in the type of debris flow. Debris flow gives a lot of economic losses and human casualties due to high moving velocity and volume of debris flow. In order to analyze movement and deposition characteristics of debris flow, numerical analysis using FLO-2D program was conducted with various viscosities and yield stresses. As a result of numerical analysis, velocity and runout distance of debris flow decreased as its viscosity increased due to resisting force between particles of debris flow. Consequently, flow depth of debris flow increased and impact force decreased. Yield stress of debris flow affected its initiation and deposition characteristics. As yield stress increased, runout distance of debris flow decreased and its impact force increased. Based on the results of numerical analysis, it was found that velocity of debris flow mainly depended on viscosity, while deposition characteristics (runout distance, deposition width, deposition area) of debris flow depended on both viscosity and yield stress.

• JSTS:Journal of Semiconductor Technology and Science
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• v.5 no.1
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• pp.30-37
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• 2005

We present an air bridge type electrode system with tunable electrode distance for detecting electroactive biomolecules. It is known that the narrower gap between electrode fingers, the higher sensitivity in IDA (interdigitated array) electrode. In previous researches on IDA electrode, narrower patterning required much precise and expensive equipment as the gap goes down to nanometer scale. In this paper, an improved method is suggested to replace nano gap pattering with downsizing electrode distance and showed that the patterning can be replaced by thickness control using metal deposition methods, such as electroplating or metal sputtering. The air bridge type electrode was completed by the following procedures: gold patterning for lower electrode, copper electroplating, gold deposition for upper electrode, photoresist patterning for gold film support, and copper etching for space formation. The thickness of copper electroplating is the distance between upper and lower electrodes. Because the growth rate of electroplating is $0.5{\mu}m\;min^{-1}$, the distance is tunable up to hundreds of nanometers. Completed electrodes on the same wafer had $5{\mu}m$ electrode distance. The gaps between fingers are 10, 20, 30, and $40{\mu}m$ and the widths of fingers are 10, 20, 30, 40, and $50{\mu}m$. The air bridge type electrode system showed better sensitivity than planar electrode.

• Journal of the Korean GEO-environmental Society
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• v.22 no.2
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• pp.25-33
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• 2021

This study was conducted to understand the deposition characteristics of debris flow and to analyze the reduction effect of debris flow damage by installing a berm. Flume experiments were performed in consideration of various channel slope and volumetric sediment concontration. In order to analyze the reduction effect of debris flow damage by installing a berm, the cases of not installing a berm and the cases of installing a berm were compared. In this study, the runout distance, total travel distance, and mobility ratio were analyzed among the deposition characteristics of debris flow. First, the deposition characteristics of debris flow according to the change of the channel slope were analyzed, and the deposition characteristics of debris flow due to the change of volumetric sediment concentration were analyzed. In addition, the change rate of debris flow deposition characteristics when a berm was installed was calculated based on the case when a berm was not installed. As a result of the experiments, it was confirmed that the channel slope and volumetric sediment concentration had a significant effect on the deposition characteristics of debris flow. In addition, when a berm is installed on the slope, the runout distance and mobility ratio of debris flow are greatly decreased, and the total travel distance is increased. This means that installing a berm delays the movement of debris flow and reduces the potential mobility of debris flow. The results of this study will provide useful information for understanding the deposition characteristics of debris flow. Furthermore, it is expected to help in the design of a berm.