• 한국전산유체공학회:학술대회논문집
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• 2008.10a
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• pp.337-339
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• 2008

Abstract: As a shock impinges into a vortex of variable strength, complex shock diffraction can occur. Since a vortex has a fixed rotating direction, the shock wave travelling in one direction creates strong asymmetry in the vortex flow field. The process is that first the shock is divided into two parts by the vortex. One part is moving in the adverse direction opposite to the vortex flow which is captured by the vortex center. The other part is moving in the favorable direction, namely, in the direction same as the vortex flow; it is swung around the vortex, accelerating the vortex flow. In this paper we have investigated numerically using ENO scheme how and why the shock-vortex interaction patterns appear so different for different parametric values. Conclusion is that there are three different types of shock-vortex interaction depending on two related parameters: shock Mach number and vortex Mach number. We present a parameter map by which we can discern what type of interaction pattern appears as a shock impinges into a vortex.

• Journal of the Korean Society of Clothing and Textiles
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• v.22 no.2
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• pp.185-192
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• 1998

The methodology of applying fabric stretch ratio in the grants pattern drafting was evaluated. The experimental fabrics employed in this study were 3 different knit fabrics with various stretch ratio in vertical or horizontal direction. The firm fitting pants pattern was modified by applying the fabric stretch ratio in vertical ana horizontal direction. The computer automatic drafting method was used for pants pattenl alteration. The suitability of the altered pattern was evaluated by the 7 clothing specialists, The results showed that fit of all experimental garments was improved in general. The garment which was constructed with the fabric having large difference between horizontal stretch ratio and vertical stretch ratio showed poor fit at crotch area. This result implies that computer aided pattern alteration is not appropriate when fabric stretch ratio is vary by the fabric directions.

• Journal of the Korean Society for Precision Engineering
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• v.24 no.2 s.191
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• pp.58-63
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• 2007

This paper proposes a novel method of projecting a multiple stripe pattern whose intensity profile is sinusoidal. The sinusoidal stripe patterns are plated with chromium on a piece of glass, and the glass is placed within an optical projection system. By linearly moving the glass along the direction of the stripe pattern, the projection system generates the motion blurring effect, and as a result, produces a blurred stripe pattern whose intensity profile is sinusoidal along the perpendicular direction of the stripe pattern. The sinusoidal pattern improves the measurement accuracy of phase-shifting method. Experimental results are provided for three different types of stripe patterns: rectangle, diamond, and sinusoid.

• Journal of Positioning, Navigation, and Timing
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• v.5 no.3
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• pp.131-136
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• 2016

The present paper shows that beamforming algorithm such as Minimum Variance Distortionless Response (MVDR) based on array antenna signal processing can have not only anti-jamming but also anti-spoofing characteristics. A beam pattern due to the beamforming algorithm strengthens received signal power as it is formed in the incident direction of desired signal. During the process, the effect of unnecessary signals such as spoofing signals can be reduced because the beam pattern reduces received signal power in the incident directions excluding the beam pattern-directed direction. In order to analyze the anti-spoofing effect due to the beamforming algorithm, a software-based simulation environment was configured. An arbitrary error was applied between incident direction of Global Positioning System (GPS) satellite signal and steering vector direction of the beamforming algorithm to analyze the received signal power and required conditions were provided to see the anti-spoofing effect due to the beamforming algorithm. The used antenna was 7-element planar circular array and beam patterns were formed through the MVDR algorithm.

• The Research Journal of the Costume Culture
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• v.16 no.6
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• pp.992-1007
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• 2008

This study was meant to offer the data for predicting the product plan answering the diverse demands for consumers based on the results of analyzing the image and formative property by transforming the stripe patterns. The concrete study way is composed of the collected stimulus centering on the interval of the stripe pattern and value contrast coloration. Consequently 192 stimuli, changed by the pattern direction and pattern interval, clothing style, and contrast coloration, are selected. The experimental materials made for this study are a set of stimuli and response scale. The statistics way used in analysis was factor analysis, ANOVA, dispersion analysis, multiple classification analysis. The results of this study were summed as following. Firstly, In the value contrast, a pair of 27 adjectives were made of attractiveness, activeness, gracefulness, visibility, and tenderness dimension. Secondly, the direction of the pattern, interval, clothing style, and contrast coloration were respectively transformed according to value contrast.

• Proceedings of the KSME Conference
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• 2000.11a
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• pp.824-828
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• 2000

Prior to the downloading of the NC codes to a machining center, the NC tool-path can be verified in a computer. The Z-map is one of the tools for the verification of NC tool-path. The Z-map is a two dimensional array in which the height values of the Z-axis direction vectors are stored. The Z-axis direction vectors are arranged in a rectangular grid pattern on the XY plane. The accuracy of the simulation comes from the grid interval. In the rectangular Z-map, the distances between the grid points are different. The distance in diagonal direction is larger than those in X or Y axis directions. For the rendering of the Z-map, a rectangular grid is divided into two triangular facets. Depending on the selection of a diagonal, there are two different cases. In this paper, triangular Z-map, in which the Z-axis direction vectors are arranged in a triangular grid pattern on XY plane, is proposed. In the triangular Z-map, the distances between grid points are equal. There is no ambiguity to make triangular facets for the rendering.

• Journal of the Korea Institute of Military Science and Technology
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• v.13 no.2
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• pp.313-319
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• 2010

GNSS receiver which uses the weak satellite signal is very vulnerable to the intentional jamming or non-intentional electromagnetic interference. One of the best method to overcome this disadvantage is to use an adaptive array antenna which has the capability of beamforming or nulling to the certain direction. In this paper, the performance of spatial adaptive null pattern control algorithm of 5 element array antenna is analyzed. A control algorithm which is designed in the 5 element array antenna is OPM(Output Power Minimization) which is eliminating the correlation characteristics between a reference antenna and the others. This algorithm can be applied effectively to the satellite navigation's CRPA because the satellite direction is not considered and GNSS signal power is below the thermal noise. The feature of the OPM algorithm is analyzed and the performance is compared with other null pattern control algorithm.

• Proceedings of the KIEE Conference
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• 1992.07a
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• pp.462-464
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• 1992

In this paper, an extraction of depth intonation in pattern using neural network is presented. All the 3D images represent the depth information in grey pixels. This pixels which have analog values translated digital values. Because of the noise and distortion in pattern, we use the normalization in learning and recalling the patterns. Our method has eight direction vectors and slopes for pattern. Also, we use potential to obtain the mean slope and direction vectors of given 3D patches. The higher level of deduction finding the global depth information is also carried out by using neural network.

• Journal of the Korean Society of Costume
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• v.60 no.1
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• pp.28-42
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• 2010

A purpose of this study is to 6nd out how the casual and formal style clothes of stripe pattern giving variety by pattern direction, pattern width, and contrast coloration have an effect on image of wearers. For this, 192 stimuli were made and 1200 testee evaluated them using semantic differential scale. As a result, five image dimensions were drawn as a factor of attractiveness, gracefulness, activeness, visibility, and tenderness. Unlike the value contrast previously researched, it showed that chroma contrast coloration which was interacted with a color tone contrast coloration had an effect on all the 5 image dimensions. This result was recognized as significant clothes dues in evaluating the image of stripe wearers. Besides, clothing style, stripe pattern, and contrast coloration were made clear as an efficient parameter in image presentation of clothing wearers.

• Korean Journal of Remote Sensing
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• v.3 no.2
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• pp.81-87
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• 1987

The study was to analysis the dispersion of the cooling water of Kori atomic power station using thermal infrared data. The dispersion pattern of the cooling water analysis clearly on the LANDSAT TM band 6. It was changed due to tidal current, that is, the cooling water disperses north-eastern direction during the low tide and southweatern direction during the high tide. The relative temperature distribution was mapped through the density slicing method on the images.