• Journal of Welding and Joining
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• v.19 no.2
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• pp.228-234
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• 2001

A methodology is developed and used to evaluate the response sensitivity of the thermal systems to variations in their design parameters. Technique for computing the sensitivity of temperature distributions to changes in processing parameters needed to decide the more effective laser input parameters for laser surface hardening treatment is considered. In this study, a state equation governing the heat flow in laser surface treatment is analyzed using a three-dimensional finite element method and sensitivity data of the processing parameter obtained using a direct differentiation method is applied to the sensitivity analysis. The interesting processing parameters are taken as the laser scan velocity and laser beam radius ( $r_{ b}$), and the sensitivities of the temperature T versus v and $r_{b}$ are analyzed. These sensitivity results are obtained with another parameters fixed. To verify the numerical analysis results, hardened layer dimensions (width and depth) of the numerical analysis are compared with the experimental ones.nes.

• Journal of Digital Contents Society
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• v.8 no.4
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• pp.541-546
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• 2007

Traditional query processing method is not efficient for continuous queries with large continuous stream data. This paper proposes a data-driven query processing method for stream data. The structure of query plan and query execution method are presented. With the proposed method, multiple query processing and sharing among queries can be achieved. Also query execution time can be reduced by storing partial results of query execution. This paper showed an example of query processing with XML data and XQuery query.

• Proceedings of the Korea Institute of Convergence Signal Processing
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• 2003.06a
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• pp.110-113
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• 2003

In this paper, the multi-channel high speed data acquisition system is implemented. This high speed signal processing system for 3-D image display is applicable to the manipulation of a medical image processing, multimedia data and various fields of digital image processing. In order to convert the analog signal into digital one, A/D conversion circuit is designed. PCI interface method is designed and implemented, which is capable of transmission a large amount of data to computer. In order to, especially, channel extendibility of images acquisition, bus communication method is selected. By using this bus method, we can interface each module effectively. In this paper, 32-channel A/D conversion and PCI interface system for 3-dimensional and real-time display of the retina image is developed. The 32-channel image acquisition system and high speed data transmission system developed in this paper is applicable to not only medical image processing as 3-D representation of retina image but also various fields of industrial image processing in which the multi-point realtime image acquisition system is needed.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.35S no.1
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• pp.141-148
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• 1998

We propose an efficient method of de-interlacing in the post-pocessing of HDTV signal. Since the proposed method considers human visual weight, it gives the better performance in the edge information preservation than that of the median filter. The processing time of the proposed method is twice faster than median filter, therefore the proposed method is suitable for the real-time de-interlacing in the post-processing of HDTV signal.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.751-755
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• 2007

The purpose of this study is to find the optimization processing on expanded tube using Taguchi method which was generally used to analyze the effects of various control factors. Mini-Tab is a good for program that is making a selection using Taguchi method. The results of experimental test and analysis are as follows. Optimization processing on a expanded tube is dependent on lubrication condition. The slight eccentricity of expanded tube was obtained a good results on the expanded tube. When expending processing on the expanded tube was performed, the test specimens were almost unaffected by changing pressure loading. The tendencies of test results were related to lubrication condition and eccentricity in expending processing. As a result, a proper lubrication condition and eccentricity in the step of design will improve the optimization processing of expanded tube.

• The Journal of the Korea Contents Association
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• v.14 no.10
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• pp.454-462
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• 2014

With the development of location aware technologies and mobile devices, location-based services have been studied. To provide location-based services, many researchers proposed methods for processing various query types with Mapreduce(MR). One of the proposed methods, is a Reverse k-nearest neighbor(RkNN) query processing method with MR. However, the existing methods spend too much cost to process the continuous RkNN query. In this paper, we propose an efficient continuous RkNN query processing method with MR to resolve the problems of the existing methods. The proposed method uses the 60-degree-pruning method. The proposed method does not need to reprocess the query for continuous query processing because the proposed method draws and monitors the monitoring area including the candidate objects of a RkNN query. In order to show the superiority of the proposed method, we compare it with the query processing performance of the existing method.

• Proceedings of the KIEE Conference
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• 2005.10b
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• pp.367-369
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• 2005

In this paper, we present a new method for the detection of spiculation on digital mammograms. Traditional methods have defects; sensitive to noise, fixed size processing, and long processing time, however, the proposed method has merits; not sensitive to noise, adaptive size processing, and fast processing time. Experimental results show that the spiculation detection performance of the proposed method is improved much compared to the other methods.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.47 no.5
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• pp.24-32
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• 2010

In this study, we have proposed a pre-processing algorithm newly developed for improving the tracking efficiency of the optical flow method. The developed pre-processing algorithm consists of a median filter, binarization, morphology, canny edge, contour detecting and an approximation method. In order to evaluate whether the optical flow tracking capacity increases, this study applied the pre-processing algorithm to the Lucas-Kanade(LK) optical flow algorithm, and comparatively analyzed its images and tracking results with those of optical flow without the pre-processing algorithm and with the existing pre-processing algorithm(composed of median filter and histogram equalization). As a result, it was observed that the tracking performance derived from the LK optical flow algorithm with the pre-processing algorithm, shows better tracking accuracy, compared to the one without the pre-processing algorithm and the one with the existing pre-processing algorithm. It seems to have resulted by successful segmentation for characteristic areas and subdivision into inner and outer contour lines.

• Design & Manufacturing
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• v.18 no.2
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• pp.23-28
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• 2024

The automobile industry is a wide range of related industries, including parts manufacturing and vehicle assembly, press processing is an essential element in making automobiles. Press processing is a processing method for metal sheets that has relatively high dimensional and shape precision and is suitable for mass production. It refers to processing by attaching a special tool, a mold, to a press machine. Recently, the automobile industry is attempting to reduce the weight of automobiles in order to reduce carbon emissions due to global warming, and the use of high-strength steel sheets, which are lighter than general structural steel sheets, is a natural trend. Shear processing is required to use high-strength steel, and the shape of the shear surface created by shear processing has a significant impact on the quality of the automobile. Therefore, various methods are being attempted to improve the share surface during shear processing. Among them, shaving processing is a method of shearing the primary shearing area again, and it is difficult to obtain an accurate answer because complex deformation occurs in the microscopic shear area. Therefore, in this study, the effect of machining allowance on shaving processing was analyzed using the finite element method using high-strength steel plate (SPFH590), and the differences were compared and examined through actual experiments under the same conditions.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.4 no.1
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• pp.56-62
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• 2004

This research attempts to suggest a detecting method for cutting position of an object using the neural network, which is one of intellectual methods, and the digital image processing method. The extraction method of object information using the image data obtained from the CCD camera as a replacement of traditional analog sensor thanks to the development of digital image processing. Accordingly, this research determines the threshold value in binary-coding of an input image with the help of image processing method and the neural network for the real-time gray-leveled input image in substitution for lighting; as a result, a specific position is detected from the processed binary-coded image and an actual system designed is suggested as an example.