• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.46 no.5
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• pp.427-435
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• 2018

Many countries are trying to deploy satellite surveillance systems for their national defense, and one of these system uses optical systems to observe the satellites above their territories. The optical satellite surveillance system requires the coordinates of the satellites in an acquired image and expects that those coordinates to be delivered to the tracking system. The proposed method detects the satellite sources in a high-resolution image with fast image processing for the optical surveillance system. To achieve faster detection, the proposed method reduces the size of the original image and approximates the trajectory of a satellite, so image processing methods are only applied to the nearby area of the approximated trajectory in the original image. The proposed method shows the similar detection performance faster than the previous method.

• Proceedings of the KSRS Conference
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• 2007.10a
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• pp.162-165
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• 2007

Chlorophyll concentration is an important factor for physical oceanography as well as biological oceanography. For these necessity many oceanographic researchers have been investigated it for a long time. But investigation using vessel is very inefficient, on the other hands, ocean color remote sensing is a powerful means to get fine-scale (spatial and temporal scale) measurements of chlorophyll concentration. Geostationary Ocean Color Imager (GOCI), for ocean color sensor, loaded on COMS (Communication, Ocean and Meteorological Satellite), will be launched on late 2008 in Korea. According to the necessity of algorithm for GOCI, we developed chlorophyll algorithm for GOCI in this study. There are two types of chlorophyll algorithms. One is an empirical algorithm using band ratio, and the other one is a fluorescence-based algorithms. To develop GOCI chlorophyll algorithm empirically we used bands centered at 412 nm, 443 nm and 555 nm for the DOM absorption, chlorophyll maximum absorption and for absorption of suspended solid material respectively. For the fluorescence-based algorithm we analyzed in-situ remote sensing reflectance $(R_{rs})$ data using baseline method. Fluorescence Line Height $({\Delta}Flu)$ calculated from $R_{rs}$ at bands centered on 681 nm and 688 nm, and ${\Delta}Flu_{(area)}$ are used for development of algorithm. As a result ${\Delta}Flu_{(area)}$ method leads the best fitting for squared correlation coefficient $(R^2)$.

• International Journal of Aeronautical and Space Sciences
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• v.16 no.4
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• pp.493-499
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• 2015

The aerodynamic performance of blunt trailing edge airfoils was investigated. The flow fields around the modified NACA64-418, which consists of the tip blade of the wind turbine and Mexico model of IEA wind, were analyzed. To imitate the repaired airfoil, the original NACA64-418 airfoil, a cambered airfoil, is modified by the adding thickness method, which is accomplished by adding the thickness symmetrically to both sides of the camber line. The thickness ratio of the blunt trailing edge of the modified airfoil, $t_{TE}/t_{max}$, is newly defined to analyze the effects of the blunt trailing edge. The shape functions describing the upper and lower surfaces of the modified NACA64-418 with blunt trailing edge are obtained from the curve fitting of the least square method. To verify the accuracy of the present numerical analysis, the results are first compared with the experimental data of NACA64-418 with high Reynolds number, $Re=6{\times}10^6$, measured in the Langley low-turbulence pressure tunnel. Then, the aerodynamic performance of the modified NACA64-418 is analyzed. The numerical results show that the drag increases, but the lift increases insignificantly, as the trailing edge of the airfoil is thickened. Re-circulation bubbles also develop and increase gradually in size as the thickness ratio of the trailing edge is increased. These re-circulations result in an increase in the drag of the airfoil. The pressure distributions around the modified NACA64-418 are similar, regardless of the thickness ratio of the blunt trailing edge.

• Journal of Fashion Business
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• v.3 no.4
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• pp.131-138
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• 1999

The purpose of this study is to measure Korean, Chinese and Chosunjok college women's body part sizes, and then, classify their body shapes according to the drop value(hip circumference-chest circumference) as well as their statures, and thereupon, comparatively analyze the statistical distribution of their major body part measurements and thereby, provide for some basic data useful to the development of quality fitting apparels exportable to China. The results of this study can be summarized as follows; Most of Korean and Chinese college women were found to belong to the body type of "N" body shape, while many of Chosunjok college women belonged to "H" body shape body type characterized by normal stature but small difference between hip and chest circumferences. The most prevailing body type of Korean and Chinese college women next to "N" type(65%, 51%) was "H" (23%, 35%), followed by "A" type(12%, 14%), while that of Chosunjok college women was "H" type (54%), followed by "N" (40%) and "A" type (6%). On the other hand, in terms of distribution of major body part sizes, there was found a wide difference between Chinese and Korean college women. Chosunjok college women had similar body part sizes to Korean college women's in such measurements as waist back length, shoulder-to-shoulder length, front interscye length, back interscye length, under-chest circumference and weight, while having simliar body part sizes to Chinese college women's in such measures as stature, arm length, waist front length, waist side-hip line length, crotch length, head circumference, neck-root circumference and waist circumference.

• Special Issue of the Society of Naval Architects of Korea
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• 2008.09a
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• pp.46-53
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• 2008

Recently, the synthetic material stern tube bush has been applied by ship owner's requirement because the synthetic material has a merit. That is to say, when stern tube seal is damaged and sea water comes into stern tube, it can work without problem because of water lubricating property. However, the material also has a demerit of temperature rise problem when some factors meets on synthetic material, for example, not sufficient lubrication oil supply and not proper shaft alignment and so on. As known in the world, the RAILKO bush is rampant for synthetic material by some ship owner because of the above mentioned reason. However, the bush has several accidents on large container vessel. Unfortunately or fortunately our yard has a chance to apply the RAILKO bush owing to requirement of specific ship owner. Therefore, it is much more required to approach the accurate shaft alignment analysis. In line with this reason, we had a shaft alignment calculation considering hull deformation and hull flexibility (hull stiffness). Also, in the calculation, we had considered dynamic condition which is reflected he propeller thrust forces and moments and oil film stiffness on the shaft alignment calculation. According to he shaft alignment calculation, bearing slope was applied on the tern tube bush and was measured. The RAILKO bush should be applied the running in procedure according to maker's recommendation for performing the oil film on the bush surface. Finally, the vessels were delivered successfully without any problem with AILKO bush as shown on his paper.

• The Research Journal of the Costume Culture
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• v.17 no.2
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• pp.203-215
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• 2009

The purpose of this study was to investigate current garment sizes of women's formal jackets, targeting plus-size women in online shopping malls, and to identify effective size information involved in online apparel purchase behaviors to overcome the short comings of current garment sizes from the perspectives of consumers. Basic 88 size formal jackets from the seven companies found on the 22 websites were collected and analyzed. The data were collected from March to October 2007, and analyzed using SPSS 14.0. The results were summarized as follows. First, there was no website using standard garment size labeling with 'bust-hip-height' set up by KS K 0051 among the 22 websites. Instead, all 22 websites used garment size labeling with figures such as 88, 99, 100, 110, and 120 or with letters such as L, XL, and XXL. The websites presented no body size, but listed garment size. Furthermore, the size information was presented differently, ranging from three items of bust circumference, upper arm length, and jacket length to six items of shoulder width, bust circumference, waist circumference, sleeve width, sleeve length, and jacket length. In addition, no website presented basic information for hip circumference, despite the jacket length covering the hips. Second, a total of 85.7% the websites listed bust circumferences in 88 garment sizes collected as 100cm. Shoulder widths were presented as 39cm or 37cm. Sleeve circumferences were addressed the same, 36cm, in all websites. Third, comparing the differences between guidance sizes and measurement sizes, only 28.5% of the web sites posted guidance sizes of shoulder widths the same as those of the measurement sizes. All web sites presented guidance sizes of bust circumstances as 1 to 5cm smaller than those of the measurement sizes.

• The Journal of the Korea Contents Association
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• v.4 no.3
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• pp.125-130
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• 2004

This paper proposes a method of the car license plate recognition from digital camera image. Lots of technology advancement has been accomplished for the least several years. The key issue for recognition rate improvement has been the extraction of correct area on the plate. In the previous studies, the information from an edge or an color on a plate hasn't been used but some declination also taken into account in most cases due to the difficulty of area extraction on a tilted plate The proposed method focuses on transforming a slant plate image to the normalized form to be recognized. It shows good robustness on situations defined by a variety of locations, slants and heights of the license plate, because it detects the edge of license plate by using both the color information and linear regression method. The computer simulation shows that the proposed method records 92％ detection rates of license plate and can recognize characters of slant plate with about 50 degrees.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.27 no.12
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• pp.609-619
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• 2015

A preprocessing scheme utilizing multi-division of the ROI (region of interest) in a chemiluminescence image during inversion is proposed. The resulting inverted image shows the flame's structure, which can be useful for studying combustion instability. The flame structure is often quantitatively visualized with PLIF (planar laser-induced fluorescence) images as well. The chemiluminescence image, which is a line-integral of the flame, needs to be preprocessed before inversion, mainly due to the inherent noise and the assumption of axisymmetry during the inversion. The feasibility of the multi-division preprocessing technique has been tested with experimentally-obtained OH PLIF and $OH^*$ chemiluminescence images of jet and swirl-stabilized flames burning substitute natural gas (SNG). It turns out that the technique outperforms two conventional methods, specifically, the technique without preprocessing and the one with uni-division, reconstructing the SNG flame structures much better than its two counterparts when compared using corresponding OH PLIF images. The characteristics of the optimum degree of polynomials to be applied for curve-fitting of the flame region data for the multi-division method involving two flames has also been investigated.

• Journal of the Korea Fashion and Costume Design Association
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• v.17 no.4
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• pp.55-66
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• 2015

The objective of this study is to propose a method by which movement fitness can be evaluated using a three-dimensional virtual garment simulation program. To this end, five types of jean pants for men were evaluated on the program by setting the avatars to make particular movements to examine the level of pressure on each body part. To verify whether the clothing pressure measurement produces valid and reliable results, virtual garment simulation program was utilized. The results indicated that there were significant differences in the levels of pressure on body parts depending on the type of test garment and motion. In addition, the clothing pressure measurement results were in line with the appearance evaluation results suggested by a previous study. Based on this set of results, the nomological validity of the clothing pressure measurement program used in this study was verified. Moreover, we employed an appearance evaluation along with the clothing pressure measurement to verify the reliability of the program; there was a high correlation between clothing pressure measurements and appearance evaluation measurements, indicating that measuring clothing pressures may well compensate for the limitations of appearance evaluation. We expect the results of this study to make valuable contributions in facilitating the digitalization of the fashion industry. Furthermore, this study also is significant in that it has suggested 3D virtual fitting programs as a solution to the long-criticized problem related to the evaluation of movement fitness in existing virtual garment simulation programs.

• Journal of the Society of Naval Architects of Korea
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• v.34 no.1
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• pp.50-59
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• 1997

Shipbuilder checks the status of main engine and propeller operation before sea trial. Generally these tests are carried out at a quay during fitting out of the ship. For these tests the operator has to estimate the maximum RPM with permissible torque and thrust to ensure the safety of the mooring line and ship. In this paper, the propeller characteristics according to the draft variation for a moored ship is inveatigated. From these tests, it is shown that shaft submergence is a dominant parameter in the propeller performance at shallow shaft submergence and that the propeller performance is dependent upon the propeller RPM when the shaft submergence is kept unchanged. In this study, a simple formula of the required thrust for a given propeller shaft submergence and propeller RPM is derived. 1be propeller thrust, which is calculated by another formula in case of dtep draft, is compared with results of bollard pull test for FPSO.