• Journal of Satellite, Information and Communications
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• v.8 no.3
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• pp.52-57
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• 2013

This paper describes the color comparison analysis of flame in each standard color model in order to propose the optimal color model for image processing based flame detection algorithm. Histogram intersection values were used to analyze the separation characteristics between color of flame and color of non-flame in each standard color model which are RGB, YCbCr, CIE Lab, HSV. Histogram intersection value in each color model and components is evaluated for objective comparison. The analyzed result shows that YCbCr color model is the most suitable for flame detection by average HI value of 0.0575. Among the 12 components of standard color models, each Cb, R, Cr component has respectively HI value of 0.0433, 0.0526, 0.0567 and they have shown the best flame separation characteristics.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.46 no.5
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• pp.359-367
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• 2018

The vortex ring state that occurs during the descending flight of a rotorcraft generates a circulating flow like a donut near the rotating surface, and it often causes a rotorcraft fall due to loss of thrust. In this paper, we have physically identified the flow field in the vortex ring state of the quadcopter, one of the types of unmanned aerial vehicles. The descending flight of the quadcopter was simulated in a 1m subsonic wind tunnel of the Korea Aerospace Research Institute(KARI) and the Particle Image Velocimetry(PIV) was used for the flow field measurement. The induced velocity in the hovering state is estimated by using the momentum theory and the test was carried out in the range of descent rate at which the vortex ring condition could be caused. The development and the direction of the vortex ring were confirmed by the measurement of the flow field according to not only the descent rate but also propeller separation distance. In addition, the results of the study show the vortex ring state can be predicted sufficiently by measuring the flow velocity around the quadcopter.

• Journal of Digital Convergence
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• v.14 no.12
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• pp.495-501
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• 2016

The film has always reflected the culture of the era based on reality and imagination. The visual effect in the film has mainly played a role of expressing the reality more realistically or recognizing the virtual as reality. This study examines the meaning and the effect of fantasy realism through Oasis of Lee Chang-dong. Fantastic realism has separated the reality from the imaginary space by using a dual meaning tool that affects the time and space in the film and reflects the human desire and desire to see. It was also reproduced in the real world through the medium of pigeons. In addition, it separates visualized space from non-visualized space in film narrative structure, separation of real and unreal space, segregation of consciousness and unconscious space, and separation of reality and reality space into power structure. With the development of technology, the image of the yellow image comes closer to us like reality, which will express the space of unconsciousness that we could not think of.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.41 no.2
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• pp.11-22
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• 2004

Conventional algorithms of separating overlapped objects are mostly based on template matching methods and thus their application domain is restricted to 2D objects and the processing time increases when the number of templates (object models) does. To solve these problems, this paper proposes a new approach of separating the occluding object from the stack of 3D objects using the relationship between surfaces without any information on the objects. The proposed algorithm considers an object as a combination of surfaces which are consisted with a set of boundary edges. Overlap of 3D objects appears as overlap of surfaces and thus as crossings of edges in 2D image. Based on this observation, the types of edge crossings are classified from which the types of overlap of 3D objects can be identified. The relationships between surfaces are represented by an attributed graph where the types of overlaps are represented by relation values. Using the relation values, the surfaces pertained to the same object are discerned and the overlapping object on the top of the stack can be separated. The performance of the proposed algorithm has been proved by the experiments using the overlapped images of 3D objects selected among the standard industrial parts.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.44 no.6
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• pp.35-46
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• 2007

This paper proposes a six-color separation method of reducing unnecessary usage of colorants based on the limitation of total colorant amount and dot visibility ordering. First, the CIELAB values of input RGB image are estimated through the color-mixing model and compared with pre-calculated CIELAB values corresponding to all combination of CMYKlclm colorants with a constraint of color difference, thereby selecting initial CMYKlclm candidates. Next, the limitation on total colorant amount Is imposed on initial CMYKlclm candidates to remove the excessive amounts of colorants, and then final CMYKlclm candidates are determined by minimizing the usage of light cyan and light magenta in the dark region based on the dot visibility ordering of C, M, Y, K, lc, and lm. Through the experiment, the proposed method is shown to reduce the excessive amount of colorants with preserving good image quality.

• Proceedings of the IEEK Conference
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• 2004.08c
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• pp.636-639
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• 2004

In present, there are many methods such as DCT, Wavelet Transform, or Quantization -to the image compression field, but the basic image compression method have based on DCT. The representative thing of the efficient techniques for information compression is DCT method. It is more superior than other information conversion method. It is widely applied in digital signal processing field and MPEG and JPEG which are selected as basis algorithm for an image compression by the international standardization group. It is general that DCT is consisted of using multiplier with main arithmetic blocks having many arithmetic amounts. But, the use of multiplier requires many areas when hardware is embodied, and there is fault that the processing speed is low. In this paper, we designed the hardware module that could run high-speed operation using row-column separation calculation method and Chen algorithm by distributed arithmetic method using ROM table instead of multiplier for design DCT module of high speed.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.6
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• pp.1143-1148
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• 2002

This paper analyses the transient response of a spherical elastic shell located near fee surface and impinged by spherical step-exponential acoustic shock waves. The problem is solved through extension of a method (Huang, 1969) previously formulated for the excitation in an infinite domain, which employs the classical separation of variables, series solutions, and Laplace transform technique The effect of the free surface reflection is taken into account using the image source method. The reflection of the incident wave has been treated by the same image formulation. If the reflection of the pressure field scattered and radiated by the shell is considered, the problem becomes that of multiple scattering by two spheres. However, this is in general negligible considering errors inherent from other sources and that the scattered and radiated pressure waves emanating from the shell are small. Thus, the problem is reduced to that of a structure immersed in an infinite fluid and impinged upon the origin and the image incident.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.38 no.9
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• pp.907-913
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• 2010

In this paper, we have described a development of the external instrumentation system of a fighter aircraft for flight test. The external instrumentation system consists of the instrumentation pod and the image pod. The instrumentation pod measures a flight data(attitude, velocity, altitude, etc) of the fighter aircraft by using GPS/AHRS sensor. The image pod takes high-speed images for the separation trajectory of a smart bomb with 2 high-speed cameras and video signal for it with one general camera. We have verified the performance of the external instrumentation system through the ground test, the environment test and the flight test.

• Proceedings of the KIEE Conference
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• 2005.05a
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• pp.45-47
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• 2005

Cleft lip is a congenital deformity condition with separation of the two sides of the lip and results in nose deformity. Evaluation of surgical corrections and outcome assessments in nose deformity resulting from the cleft lip depend mainly on doctor's objective judgment. Development of an objective assessment tool in evaluation of the condition and surgical outcome of cleft lip nose deformity patients will help in advancement and evaluation of surgical techniques of cleft lip. Hence, our study aimed on quantitative assessment of a cleft lip nose deformity condition by comparing following parameters gathered from a photographic image of a cleft lip patient: (1) angle difference between two nostril axis, (2) center of the nostril and distance between two centers, (3) overlapped area of two nostrils and (4) the overlapped area ratio of two nostrils. Assessment results of the nose deformity were determined by statistical analysis of evaluation results from three greatly experienced plastic surgeons. In addition, regression model was developed using correlation relationship and factor analysis of parameters from results of the image analysis.

• Journal of the Korea Society of Computer and Information
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• v.11 no.6 s.44
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• pp.1-8
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• 2006

Many researchers have been studied for the automatic chromosome karyotype classification and analysis. For the automatic classify the each chromosome which is the image in microscope, it is necessary to process the sub-procedure, ie. image pre-processing, implementing karyotype classifier. The image pre-processing proceeded the each chromosome separation, the noise exception and the feature parameter extraction. The extracted morphological feature parameter were the centromeric index(C.I.), the relative length ratio(R.L.), and the relative area ratio(R.A.). In this paper, the fuzzy classifier was implemented for the human chromosome karyotype classification. The extracted morphological feature parameter were used in the input parameter of fuzzy classifier. We studied about the selection of the membership function for the optimal fuzzy classifier in each chromosome groups.