• Proceedings of the SAREK Conference
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• 2004.06a
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• pp.54-54
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• 2004

• Proceedings of KOSOMES biannual meeting
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• 2017.11a
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• pp.71-71
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• 2017

• Journal of the Society of Naval Architects of Korea
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• v.53 no.4
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• pp.290-299
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• 2016

The most powerful energy resource in nature is solar energy which becomes directly converted to electric power in worldwide. Most of the photovoltaic power plants are commonly installed on sunny side of the ground. Thus the installation of photovoltaic power plant could produce an unexpected adverse effect by sacrificing the productivity from green field or forest. To avoid these adverse effect floating photovoltaic plant has been devised and installed on inland reservoir. The photovoltaic plant could utilize ignored water surface without sacrificing the productivity of the ground. Additionally the photovoltaic efficiency has been reenforced by the cooling effect induced by the circulating air flow from water surface. The floating photovoltaic plant could be furnished solar tracking ability by tilting the system operated with the aid of the ballast system. This report is provided to introduce the design of the floating structure with solar panel which furnished solar tracking ability with the aid of ballast system.

• Journal of Food Hygiene and Safety
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• v.22 no.4
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• pp.288-293
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• 2007

To evaluate effects of airborne microorganisms in fresh cut processing plant, microorganisms in air, equipments, raw material, water and final product were isolated and identified using Vitek (R)2 compact system. Airborne microorganisms were isolated from 1000L air using air sampler for floating microorganisms and plate count agar for falling microorganisms. And contaminated microorganisms of equipment, water, and product were isolated from plate count agar plate. Total plate counts for floating and falling, raw material, equipments and final product were $10^2-10^3CFU/m^3,{\sim}10^1CFU/plate,\;10^3CFU/g,{\sim}10^4CFU/cm^2\;and\;10^4CFU/g$, respectively. From the result of isolated microorganism identification from raw material to final product, airborne microorganisms could affect the flora of final product.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.5 no.3
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• pp.209-214
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• 1995

Abstract 0.2 wt % $Fe_2O_3$ doped $SrTiO_3$ single crystals were grown by floating zone method in air and Nz atmosphere, respectively. The growth rate was fixed at 5 mm/hr and rotation speed was maintained at 30 rpm. As - grown crystals were cut perpendicular to its growth direction and then, annealed at 900, 1000 and $1100^{\circ}C$ for 2 hours in Nz atmosphere. Resistivities of each samples were measured and then converted into conductivities. By using these conductivity values, the activation energies were calculated and by means of the calculated activation energies, mechanism which contribute to increasing the electrical conductivity were investigated.

• Journal of Power System Engineering
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• v.20 no.3
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• pp.5-10
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• 2016

The structure of the variable liquid column oscillator(VLCO) is analogous to that of the tuned liquid column damper used to suppress oscillatory motion in large structures like tall buildings and cargo ships. VLCO is using the technology which absorbs high potential energy made by process of accelerated motions effect of air spring by installation of inner air chamber. So, the application of VLCO can improve the efficiency of energy than that of wave energy converters made in Pelamis Company. In this research, experiments were performed for the models which have two different liquid column sizes. In order to find out the biggest motion response, two major conditions are taken into account. Two conditions are to open(or close) the valves and to differentiate the height of the liquid column.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.22 no.10
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• pp.672-678
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• 2010

The purpose of this study is to develop a stacking guidance system (SGS) of containers in the mobile harbor (MH). A mobile harbor is a floating structure especially designed for loading and unloading containers from and to a large container ship. A novel stacking guidance system was proposed for unloading the container in an effective way against possible vibrations of the floating body. The guidance system works as an aid for loading containers with a wider opening for easier stacking of a container into a moving storage cell due to waves. In order to determine the most effective inclination angle of the cell-guide, this study performed the dynamic analysis of the SGS equipped in the MH subject to fluctuations of the sea. The motions of the guidance system and a container loaded were calculated using ADAMS. The simulation results of the contact force between the two rigid bodies showed that a desirable angle of the cell-guide should be around 20 degrees from the vertical. This proposed SGS can considerably reduce the loading and unloading time, and will enhance the performance of the MH.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2013.10a
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• pp.287-288
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• 2013

Concerns on the floating architecture development has been increased on the viewpoint of ocean space due to the increases of GDP and environmental issues such as sea level rise. However, basic research on the water heat exchanger for utilizing seawater thermal energy is insufficient. So, The purpose of this research is to develop a sea water heat exchanger model and to evaluate the performance throughout the experiment for seawater heat utilization.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.5
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• pp.475-481
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• 2004

This paper presents a force model of the clean tube system, which was developed as a means of transferring air-floated wafers inside a closed tube filled with super clean air. The recovering force from the holes for floating wafers is modeled as a linear spring and thus the wafers motion is modeled as a mass-spring-damper system. The propelling forces are modeled as linear along with the wafer location. The paper also proposes a control method to emit and stop a wafer at the center of a control unit. It reveals the minimum value of the propelling force to leave from the control unit. In order to stop the wafer, it utilizes the exact time when the wafer arrives at the position to activate the propelling force. Experiments with the clean tube system built for the 12 inch wafer shows the validity of the proposed model and the algorithm.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.12
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• pp.45-56
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• 2002

A pneumatic servo system requiring a fine gap control in a photo-electric sensor which is used for a LCD array detection device is introduced. The gap controlled by the pneumatic servo system remains within around 50~80 ${\mu}{\textrm}{m}$, and the system possesses an effect to eliminate undesirable particles on the LCD plate by blowing air out. The air flow rate is initially controlled by a servo valve and expanded by a booster valve, thus the controlled air pressure contributes to maintaining an appropriate gap between the LCD plate and photo-electric sensor An air floating plate of two degrees of freedom is designed and fabricated, and a fine tilting motion control is also implemented by assigning different gap commands. The pressure control and direct gap control are proposed, and each performance is verified experimentally.