• Journal of the Institute of Electronics and Information Engineers
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• v.54 no.5
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• pp.65-73
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• 2017

In this paper, we propose a stereo matching method to improve the image quality at the hole and the disparity discontinuity regions. The stereo matching method extracts disparity map finding corresponding points between stereo image pair. However conventional stereo matching methods have a problem about the tradeoff between accuracy and precision with respect to the length of the baseline of the stereo image pair. In addition, there are hole and disparity discontinuity regions which are caused by textureless regions and occlusion regions of the stereo image pair. The proposed method extracts initial disparity map improved at disparity discontinuity and miss-matched regions using modified AD-Census-Gradient method and adaptive weighted cost aggregation. And then we conduct the disparity map refinement to improve at miss-matched regions, while also improving the accuracy of the image. Experimental results demonstrate that the proposed method produces high-quality disparity maps by successfully improving miss-matching regions and accuracy while maintaining matching performance compared to existing methods which produce disparity maps with high matching performance. And the matching performance is increased about 3.22(%) compared to latest stereo matching methods in case of test images which have high error ratio.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.29 no.1
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• pp.101-109
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• 2011

This paper describes the attempts to improve the performance of an image matching method for multiple image. Typically, matching between two images is performed by using correlation between a reference and corresponding images. The proposed multiple image matching algorithm performs matching in an object space, chooses the image closest to the true vertical image as a reference image, calculates the correlation based on the chosen reference image. The algorithm also detects occluded regions automatically and keep them from matching. We could find that it is possible to create high quality DEM by this method, regardless of the location of image. From the performance improvement experiments through the occlusion detection, we could confirm the possibility of a more accurate representation of 3D information.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.5
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• pp.1597-1610
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• 2022

At present, the main method of high-speed train chassis detection is using computer vision technology to extract keypoints from two related chassis images firstly, then matching these keypoints to find the pixel-level correspondence between these two images, finally, detection and other steps are performed. The quality and accuracy of image matching are very important for subsequent defect detection. Current traditional matching methods are difficult to meet the actual requirements for the generalization of complex scenes such as weather, illumination, and seasonal changes. Therefore, it is of great significance to study the high-speed train image matching method based on deep learning. This paper establishes a high-speed train chassis image matching dataset, including random perspective changes and optical distortion, to simulate the changes in the actual working environment of the high-speed rail system as much as possible. This work designs a convolutional neural network to intensively extract keypoints, so as to alleviate the problems of current methods. With multi-level features, on the one hand, the network restores low-level details, thereby improving the localization accuracy of keypoints, on the other hand, the network can generate robust keypoint descriptors. Detailed experiments show the huge improvement of the proposed network over traditional methods.

• Journal of the Korea Convergence Society
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• v.8 no.11
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• pp.85-91
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• 2017

This paper concerns the design of a matching module system enabling the RF signal to be harmonized between the new base stations (RRH) and the repeater in the same frequency band of the asynchronous transfer network. This matching system controls the RF Gain Control of the module while monitoring the quality of the quality. Additionally, the RF environment has been adapted accordingly to adjust the RF Gain Control to match the receiver characteristics of the relay. As a result of this study, we improved the quality of the interface between the new base stations and existing relays.

• The Korean Journal of Rehabilitation Nursing
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• v.6 no.1
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• pp.40-50
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• 2003

Purpose: To investigate audiometery and characteristics related to tinnitus in tinnitus patients, and to understand the relationship between the discomfort of tinnitus and the quality of life. Methods: The subjects were 110 patients with tinnitus. The data were collected using tinnitus handicap questionnaire, quality of life, and pure tone audiometry, which measured hearing level in dB and frequency in Hz matching of tinnitus. Results: Majority of tinnitus patients (75.5%~81.8%) had normal auditory sensation. but 82.7% of patients indicated that they have heard tinnitus "frequently" or "always", and the major sounds of tinnitus were "wing, wung, wang". The matching sounds of tinnitus had various range in hearing level(dB) and frequency(Hz). Tinnitus patients reported moderate levels of the discomfort of tinnitus and the quality of life, and there were negative correlation between the discomfort of tinnitus and the quality of life(r=-.314, p<.001). Conclusion: These findings suggest that special attention is needed for tinnitus patients because the physical, psychological, and social impacts of tinnitus could be decrease their quality of life. Specialized nursing intervention considering specific conditions related to tinnitus is required to solve various health problems of tinnitus patients.

• Proceedings of the Korea Contents Association Conference
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• 2005.05a
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• pp.362-368
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• 2005

This paper is related to the fast block matching algorithm, especially a method for expanding the search pattern using the second local matching point in the adaptive hexagonal search. To reduce the local minima problem in fast motion estimation, the proposed method expands the search pattern by adding new searching points selected by using the second local matching point to conventional search pattern formed by the first local matching point in the adaptive hexagonal search. According to estimating the motion vector by applying block matching algorithm based on hexagonal search to the expanded search pattern, the proposed method can effectively carry out fast motion estimation to improve the performance in terms of compensated image quality.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.5
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• pp.581-586
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• 2017

The facility modernization policy has been established to improve fruits quality and to increase fruits yield per acreage. The fruit production quantity of farms joined in the policy was increased. Therefore, many fruit farms want to participate in the policy. The government has subsidized fruit farms to modernize their facilities such as rain proof, drainage way, frost proof, etc. This study analyzes the performance of the facility modernization policy focused on apple, eastern pear, and grape cultivation sector. One hundred apple farms, one hundred eastern pear farms, and 91 grape farms were surveyed. The performance of the policy was reviewed using analytical technique such as Covariate Matching and Propensity Score Matching and several policy implications were suggested.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37C no.10
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• pp.933-939
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• 2012

In general, the three-dimensional(3D) coordinates of the manufactured ship blocks are measured using the laser measuring equipment by ship engineers. But, many deflections between the measured coordinates in manufactured step and the designed coordinates in the design step are occurred because of the measuring process of ship blocks manually. Thus, the ship engineer should conform the consistency between the measured coordinates and the designed coordinates step by step, and it largely causes the loss of manpower and time. In this paper, the automated pattern matching algorithm of 3D coordinates for quality control in ship blocks is suggested in order to solve this problem, and the performance of the algorithm is analyzed using the 3D coordinates simulation software developed by our research laboratory. The coordinates matching rate of the measured coordinates in the single/multi ship block(s) is about 90.2% under the tolerated distance error range is 20~25cm.

• Journal of KIISE:Computing Practices and Letters
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• v.16 no.2
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• pp.242-246
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• 2010

In this paper, we propose a quality assessment method of biometrics for estimating an authentication result in an user authentication system. The proposed quality assessment method is designed to compute a quality score called CIMR (Confidence Interval Matching Ratio) as a result by small-sample analysis like T-test. We use the C/MR-based quality assessment method for testing how to well draw a distinction between various biometrics in a multimodal biometric system. We also test a predictability for authentication results of obtained biometrics using the mean $\bar{X}$ and the variance $s^2$ in T-test-based CIMR. As a result, we achieved the maximum 88% accuracy for estimation of user authentication results.

• Journal of the Korean Data and Information Science Society
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• v.18 no.4
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• pp.879-890
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• 2007

Statistical matching is a method of data integration for data sources that do not share the same units. It could produce rapidly lots of new information at low cost and decrease the response burden affecting the quality of data. This paper proposes a statistical matching technique combining k-NN (k-nearest neighborhood) and regression methods. We select k records in a donor file that have similarity in value with a specific observation of the common variable in a recipient file and estimate an imputation value for the recipient file, using regression modeling in the donor file. An empirical comparison study is conducted to show the properties of the proposed method.