• The Journal of the Convergence on Culture Technology
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• v.9 no.1
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• pp.525-530
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• 2023

Although double-stage hanger is used in many homes for its space utilization and ease of installation, it is inconvenient for users to take off clothes hung on the upper bar due to its high height. Therefore, this paper proposes a new type of double-stage hanger that allows users to easily hang or take out clothes hung on the upper bar while maintaining the function of the existing double-stage hanger. 4-bar link mechanism is applied so that the upper bar can come down to a convenient height with one operation. In addition, an appropriate link shape, length, and joint type are selected so that the height is adjusted three-dimensionally to prevent overlapping of clothes hanging on upper/lower bars. FEA analysis is performed to ensure that the presented hanger shape can support the load of clothes during height adjustment and the feasibility of the three-dimensional height adjustment hanger is verified through fabrication.

• Journal of Aerospace System Engineering
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• v.14 no.5
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• pp.107-121
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• 2020

The performance analysis of the small satellites launch vehicle using the electric pump cycle as the upper stage engines was performed. The first stage is the launch vehicle that uses the test launch vehicle of the Korea Space Launch Vehicle II and the second stage employs elecpump cycle engine that uses liquid methane and kerosene (RP-1) as fuel. A model for the mass estimation was presented and the analysis was conducted for the range of thrust of 20 to 40 kN and combustion pressure of 3 to 6 MPa with a nozzle expansion ratio of 60 to 100. The mixture ratio with the maximum velocity increment was calculated and the performance of the LEO and SSO payload were calculated from the stage mass estimation. In both the cases, liquid methane, and RP-1 showed maximum payload for 20 kN thrust, 3 MPa combustion pressure, and the nozzle expansion ratio of 100, with a mixture ratio of 3.49 for liquid methane and 2.75 for RP-1. In addition, the ditching points of the first stage and the fairing in the LEO mission were analyzed using ASTOS.

• Applied Microscopy
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• v.30 no.1
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• pp.89-100
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• 2000

We observed the salivary ducts of two species of snails, Achatina fulica and Incilaria fruhstoferi with an electron microscope, and obtained the following results. The intralobular and interlobular ducts of Achatina fulica assume the forms of round or ellipsoidal doughnuts. The boundaries between the endothelial cells are not clear. It is also found that the cytoplasm of the endothelial cells consists of the membrane infolded in interdigital form, and there are well -developed microvilli at the apical portion of the cytoplasm. On the other hand, the intralobular and interlobular ducts of Incilaria fruhtoferi consist of the irregular simple columnar epithelia. The high electron dense cytoplasm is filled with the irregular round granules. The microvilli at the apical portion of the cytoplasm are not so well-developed as those in Achatina fulica. In the salivary duct of Achatina fulica, the lumen has narrow and long tubular structure. The boundaries between the endothelial cells are not clear. The cytoplasm is full of many vacuoles and electron lucent granules. At the apical portion of the cytoplasm, lots of short and thin microvilli are found. The salivary duct of Incilaria fruhstorferi is wider ($65\times250{\mu}m$ in diameter) than that of Achatina fulica, and consists of endothelial cells of the same structures. At the apical portion of those endothelial cells, a lot of junction apparatus such as desmosomes are observed. The vessels in the salivary ducts of Achatina fulica and Incilaria fruhstoferi are observed mainly in the connective tissues between the salivary glands. The endothelial cell of the vessel has the irregular structure and looks dark due to the high electron density. These cells protrude their filopodia and phagocytosize foreign bodies.

• Journal of Bio-Environment Control
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• v.16 no.3
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• pp.186-193
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• 2007

Effects of deficit irrigation by different soil moisture-based water potential on the reduction of green shoulder fruits in fresh tomato were investigated. Deficit irrigation with -30 kPa treatment significantly reduced green shoulder fruit by 53.7% compared to the -15 kPa treatment. The total concentrations of potassium in levels of whole fruit was not different between normal red fruit (NRF) and green shoulder fruit (GSF). However, the concentrations of potassium in distal part of GSF lower than that of a basal part of GSF Total soluble sugar contents in NRF and GSF were increased during the maturation periods. Contents of starch in NRF and distal part of GSF were decreased during the maturation periods. However, contents of starch in basal part of GSF was not change during the maturation periods. Activity of sucrose phosphate synthase was higher in NRF than that of GSF. Activity of acid invertase in NRF and GSF decreased rapidly during the maturation periods. Activity of acid invertase was significantly different in distal and basal part of GSF. Total activities of peroxidase and alcohol dehydrogenase in NRF were higher than that of GSF.

• The Journal of Korean Academy of Prosthodontics
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• v.54 no.2
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• pp.110-119
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• 2016

Purpose: This study is aimed to assess changes of stress distribution dependent on different connection lengths and placement of the fixture top relative to the ridge crest. Materials and methods: The internal-conical connection implant which has a hexagonal anti-rotation index was used for FEM analysis on stress distribution in accordance with connection length of fixture-abutment. Different connection lengths of 2.5 mm, 3.5 mm, and 4.5 mm were designed respectively with the top of the fixture flush with residual ridge crest level, or 2 mm above. Therefore, a total of 6 models were made for the FEM analysis. The load was 170 N and 30-degree tilted. Results: In all cases, the maximum von Mises stress was located adjacent to the top portion of the fixture and ridge crest in the bone. The longer the connection length was, the lower the maximum von Mises stress was in the fixture, abutment, screw and bone. The reduction rate of the maximum von Mises stress depending on increased connection length was greater in the case of the fixture top at 2 mm above the ridge crest versus flush with the ridge crest. Conclusion: It was found that the longer the connection length, the lower the maximum von Mises stress appears. Furthermore, it will help prevent mechanical or biological complications of implants.

• Journal of Korean Society of Forest Science
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• v.94 no.6
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• pp.468-475
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• 2005

To understand spatiotemporal changes of temperature and humidity in Lentimula edodes cultivation sheds, temperature, relative humidity were measured with HOBO H8 series sensors in log cultivation sheds and sawdust cultivation sheds. The results obtained from October in 2003 to October in 2004 were as follows; 1. Horizontal temperature changes were smaller at center of cultivation shed inside than comer of cultivation shed inside, while relative humidity changes were greater about 3% at center of cultivation shed inside than corner of cultivation shed inside. 2. Vertical temperature changes showed that the temperature was higher at above than at below when the temperature rises, while the temperature was lower at above than at below when the temperature falls. Thus close to soil surface temperature showed a little fluctuation. Vertical relative humidity changes showed that the relative humidity was lower at above than at below when the temperature rises, while the relative humidity was higher at above than at below when the temperature falls. After all temperature and relative humidity was the opposite in cultivation shed. 3. It's showed in log cultivation shed that the minimum temperature was a subzero temperature until the end of April, while the minimum temperature did above zero after the beginning of the May. Besides a winter was the greatest at daily temperature range during the four season, about $30^{\circ}C$. On the other hand the minimum relative humidity was less than 20% at April, May and June but more than 40% after May.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39C no.11
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• pp.985-993
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• 2014

This paper suggested a new evaluation method for optimal HUD position through a correlation based on between biological signal as and statistical analysis which using (Electroencephalogram, EEG) and ANOVA. This experiment was conducted two kinds of method to evaluate the optimal HUD position. At first, visual stimulus suggested from six different positions(the top and the bottom of the left, the top and the bottom of the center and the top and the bottom of the right on the screen) in laboratory and an object image was shown for 30 seconds in a screen which has $235{\times}197cm2$ size. And second, HUD image was configured from three different positions and an object image was shown for 30 seconds in a screen. EEG, which used ${\alpha}$-wave and ${\beta}$-wave for evaluate an emotional stability, were measured from Fp1, Fp2, F7 and F8 channel based on ten to twenty electrode system. From the result in laboratory, F7 ${\beta}$-wave was shown statistically significant to significance probability of 0.006 and between ${\alpha}$-wave and ${\beta}$-wave were showed a negative correlation(r=-0.190). Also, Both the top of left and the bottom of center were showed lower ${\beta}$-wave than the bottom of right. From the result in railway simulator, Fp1 ${\beta}$-wave was appeared statistically significant as significance probability of 0.033 and it was showed lower ${\beta}$-wave than center. The outcome of this study will be helpful about evaluation of optimal HUD position through correlation between alpha wave and beta wave.

• Korean Journal of Remote Sensing
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• v.24 no.6
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• pp.535-549
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• 2008

Vicarious calibration for the satellite sensor relies on simulated TOA (Top-of-Atmosphere) radiances over various targets. In this study, TOA visible radiance was calculated over ocean targets which are located in five different regions over the Indian and Pacific ocean, and its possible use for the satellite sensor calibration was examined. TOA radiances are simulated with the 6S radiative transfer model for the comparison with MODIS/Terra and SeaWiFS measurements. Geometric angles and sensor characteristics of the reference satellites were taken into account for the simulation. AOT (Aerosol Optical Thickness) from MODIS/Terra, pigment concentrations from Sea WiFS, and ozone amount from OMI measurements were used as inputs to the model. Other atmospheric input parameters such as surface wind and total column water vapor were taken from NCEP/NCAR reanalysis data. The 5-day averaged radiances over all targets show that the percent differences between simulated and observed radiances are within about ${\pm}5%$ in year 2005, indicating that the calculated radiances are in good agreement with satellite measurements. It has also been shown that the algorithm can produce the SeaWiFS radiances within about ${\pm}5%$ uncertainty range. It has been suggested that the algorithm can be used as a tool for calibrating the VIS bands within about 5% uncertainty range.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2009.10a
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• pp.601-602
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• 2009

• Geotechnical Engineering
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• v.34 no.4
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• pp.12-21
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• 2018