• Journal of Korea Multimedia Society
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• v.13 no.5
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• pp.722-729
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• 2010

Prediction problems are widely used in medical domains. For example, computer aided diagnosis or prognosis is a key component in a CDSS (Clinical Decision Support System). SVMs with nonlinear kernels like RBF kernels, have shown superior accuracy in prediction problems. However, they are not preferred by physicians for medical prediction problems because nonlinear SVMs are difficult to visualize, thus it is hard to provide intuitive interpretation of prediction results to physicians. Nomogram was proposed to visualize SVM classification models. However, it cannot visualize nonlinear SVM models. Localized Radial Basis Function (LRBF) was proposed which shows comparable accuracy as the RBF kernel while the LRBF kernel is easier to interpret since it can be linearly decomposed. This paper presents a new tool named VRIFA, which integrates the nomogram and LRBF kernel to provide users with an interactive visualization of nonlinear SVM models, VRIFA visualizes the internal structure of nonlinear SVM models showing the effect of each feature, the magnitude of the effect, and the change at the prediction output. VRIFA also performs nomogram-based feature selection while training a model in order to remove noise or redundant features and improve the prediction accuracy. The area under the ROC curve (AUC) can be used to evaluate the prediction result when the data set is highly imbalanced. The tool can be used by biomedical researchers for computer-aided diagnosis and risk factor analysis for diseases.

• Journal of KIISE:Computing Practices and Letters
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• v.9 no.6
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• pp.646-661
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• 2003

It is not easy that we visualize the large volume data stored in the every client computers of the web environment. One solution is as follows. First we compress volume data, second store that in the database server, third transfer that to client computer, fourth visualize that with direct-volume-rendering in the client computer. In this case, we usually use wavelet transform for compressing large data. This paper reports the experiments for acquiring the wavelet bases and the compression ratios fit for the above processing paradigm. In this experiments, we compress the volume data Engine, CThead, Bentum into 50%, 10%, 5%, 1%, 0.1%, 0.03% of the total data respectively using Harr, Daubechies4, Daubechies12 and Daubechies20 wavelets, then visualize that with direct-volume-rendering, afterwards evaluate the images with eyes and image comparison metrics. When compression ratio being low the performance of Harr wavelet is better than the performance of the other wavelets, when compression ratio being high the performance of Daubechies4 and Daubechies12 is better than the performance of the other wavelets. When measuring with eyes the good compression ratio is about 1% of all the data, when measuring with image comparison metrics, the good compression ratio is about 5-10% of all the data.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2003.10a
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• pp.251-256
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• 2003

Conventional 2D GIS has many difficulties to visualize and analyze three dimensional real world. To improve those problems and implement realistic spatial analysis, Interest in 3D GIS is increasing remarkably. Currently, Some local governments are carrying out pilot projects for 3D GIS, Government also is setting up the master plan and the road map for national information construction. In this study, introducing 3D GIS to urban planning, we evaluated limits of conventional regulation and proposed effective and reasonable means lot restricting location of merrymaking place in local government.

• Journal of Ocean Engineering and Technology
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• v.9 no.2
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• pp.83-88
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• 1995

In this paper, the solid modeller suitable for PC was developed for Top-down 3-D representation and analysis of fixed offshore structures. Also solid modelling and hidden line removal were conducted in order to visualize the offshore structures based on the scan line z-buffer algorithm.

• Proceedings of the KWS Conference
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• 1999.10a
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• pp.146-149
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• 1999

To develope the high speed gas cutting tip, consists of 3 pieces, supersonic axisymmetric jets issuing from various kinds of nozzles with a throat diameter of a few milimeters were experimentally investigated. The nozzle inlet pressure was varied from 4 to 8 kgf/$\textrm{cm}^2$. The parameters in nozzle design were throat diameter, throat length, taper angle, outlet diameter. The total pressure variation was measured by the pilot tube, 0.5mm outer diameter, along the center of the free stream jet. Also color Shilieren system was used to visualize the flowfield.

• Proceedings of the Acoustical Society of Korea Conference
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• 1998.06c
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• pp.239-242
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• 1998

A new real time sound field visualization technique is introduced in this study using PIV(Particle Imaging Velocimetry) technique. Small particles of which density is small enough to follow up the air flow are used for sound visualization. When the driving frequency is in the vicinity of the resonance frequency of the simplified 2-dimensional muffler system, an acoustic streaming is shown and of which velocity distribution is obtained through PIV technique. It is experimentally proved that the present technique is able to visualize and quantify the sound field's energy flow.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.799-802
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• 2001

For imaging of concrete specimens using radar, principles of radar and signal processing are discussed. Experimental data obtained from radar measurement of two different concrete specimens at two different frequency bandwidths of 2~3.4 GHz, 3.4~5.8 GHz and these two frequencies are combined to show better imaging. A signal processing scheme has been implemented to visualize the concrete specimens. Through combined frequency, imaging results of concrete specimens were improved.

• 한국연소학회:학술대회논문집
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• 2001.06a
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• pp.17-22
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• 2001

The flow induced by a circular jet vertically impinging under a horizontal plate is investigated by visualization technique, using kerosene smoke in nitrogen gas to visualize the flow in the vortex as well as under the plate. The light source was the sheet beam of Ar-Ion laser. The vertical and 3-dimensional images of vortices were recorded by the digital video camera.

• Journal of the Korean Operations Research and Management Science Society
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• v.18 no.3
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• pp.101-111
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• 1993

The purpose of this paper is to show the graphic representation of a linear programming problem by a projection method. First, we develop a projection method which conserves the optimality in the projected space, and next we introduce an algorithm to visualize the feasible solution set and the solution process by the projection method. Finally, we give an example to represent a 4-dimensional linear programming problem graphically.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1999.10a
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• pp.371-373
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• 1999

자동차가 급증하면서 '98년도에는 1000만대를 넘어서고 있다. 대도시 대기오염의 주요 오염원으로서 이동오염원인 자동차에 의한 대기오염의 정도도 날로 증가하고 있으며, 특히 경유차량에 의한 NOx 및 PM의 저감을 위한 대책 마련이 시급한 실정이다. 대도시의 대기오염 저감대책 수립 및 저감효과에 대한 평가를 위해 차종별, 지역별 오염물질의 발생 또는 분포현황이 파악되어야 한다.(중략)