• Proceedings of the KSRS Conference
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• 2005.10a
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• pp.169-172
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• 2005

Modem SAR interferometry (IFSAR) sensors delivering intensity images and corresponding digital terrain model (DTM) allow for a thorough surface lineament interpretation with the all-weather day-night applicability. In this paper, an automatic linear-feature detection algorithm for high-resolution SAR images acquired in Taiwan is proposed. Methodologies to extract linear features consist of several stages. First, the image denoising techniques are used to remove the speckle noise on the raw image. In this stage, the Lee filter has been chosen because of its superior performance. After denoising, the Coefficient of Variation Detector is performed on the result images for edge enhancements and detection. Dilation and erosion techniques are used to reconnect the fragmented lines. The Hough transform, which is a special case of a more general transform known as Radon transform, is a suitable method for line detection in our analysis. Finally, linear features are extracted from the binary edge image. The last stage contains many substeps such as edge thinning and curve pruning.

• Journal of Biosystems Engineering
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• v.23 no.4
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• pp.381-390
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• 1998

An algorithm to extract the 3-D geometric information of a static object was developed using a set of 2-D computer vision system and a laser structured lighting device. As a structured light pattern, multi-parallel lines were used in the study. The proposed algorithm was composed of three stages. The camera calibration, which determined a coordinate transformation between the image plane and the real 3-D world, was performed using known 6 pairs of points at the first stage. Then, utilizing the shifting phenomena of the projected laser beam on an object, the height of the object was computed at the second stage. Finally, using the height information of the 2-D image point, the corresponding 3-D information was computed using results of the camera calibration. For arbitrary geometric objects, the maximum error of the extracted 3-D feature using the proposed algorithm was less than 1~2mm. The results showed that the proposed algorithm was accurate for 3-D geometric feature detection of an object.

• Proceedings of the KIEE Conference
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• 1993.11a
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• pp.314-316
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• 1993

In this paper, a method to detect and diagnose faults in Automated Manufacturing Systems(AMS) is proposed. In AMS, it is necessary to monitor the process-status. The detection and diagnosis of faults are often difficult in monitoring level with given passive data. We propose the model-based monitoring system for faults detection and diagnosis using Petri Nets to model AMS efficiently and easily. Simulation results show the validity of proposed method with example of Reverse Mill Process in Automated Mill Lines.

• Journal of Korea Spatial Information System Society
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• v.1 no.1 s.1
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• pp.49-55
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• 1999

Extracting information of maps is necessary to establish the GIS. In this paper, a house recognition method on the scanned topographic map is described. A contour detection method is used to extract houses from the scanned maps and RLE (run-length encoding) method is used for manipulating houses touching grid lines. To handle houses touched to roads and borderlines, morphological operation is used. To remove misrecognition occurred by morphological operation, the legions which contain characters on the map are also automatically eliminated.

• Journal of the Korean Society of Safety
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• v.20 no.1 s.69
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• pp.30-35
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• 2005

This study proposes construction of through transmission for weld defects detection of rail weld zone from ultrasonic signals. For these purposes, the ultrasonic signals for defects(porosity and crack) of weld zone in rails are acquired in the type of time series data and echo strength. 6 lines in the distance amplitude characteristics curve(DACC) indicated damage evaluation standard of weld zone in rails. The acquired ultrasonic signals agree flirty well with the mesured results of reference block and sensitivity block(defect location beam propagation distance, echo strength, etc). The proposed construction of through transmission in this study can be used for weld defects detection of rail weld zone.

• ETRI Journal
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• v.9 no.3
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• pp.74-85
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• 1987

In this paper, a new kind of dual tone multifrequency receiver(DTMFR) is proposed, in which detection is made in terms of the partial correlation(PARCOR) coefficients for efficient DTMF signal detection against both temporary decoding errors by crosstalks possibly coming from adjoint telephone lines during transmission and so-called digit simulation by background voice or noise signals during interdigit period. A simulation study on the behaviour of PARCOR coefficients for tone signals and non-signals has been performed in order to provide the rationale on the feasibility of the proposed DTMFR algorithm. Based upon simulation results, a more refined detection strategy as an example is presented and explained together with the corresponding decision logic.

• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.335-337
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• 2003

The protection against transient instability and consequent out-of-step condition is a major concern for the utility. The unstable system may cause serious damage to system elements such as generators and transmission lines. Therefore, out-of-step detection is essential to operate a system safely. This paper presents the Out-of-Step detection algorithm using voltage frequency variation. The digital filters based on Discrete Fourier Transforms (DFT) to calculate the frequency of a sinusoid voltage are used, and the generator angle is estimated using the variation of the calculated voltage frequency. The proposed out-of-step algorithm is based on the assessment of a transient stability using equal area criterion. The proposed out-of-step algorithm is verified and tested by using EMTP MODELS.

• BMB Reports
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• v.33 no.6
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• pp.537-540
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• 2000

A simplified but reliable method was developed for the polymerase chain reaction (PCR)-based detection of genetically modified (GM) plants. The modified CTAB (mCTAB) method enabled us to prepare a high quality of genomic DNA from several hundred plant leaf samples in one day. Using DNA samples prepared from seven dicots and two monocots, approximately 1.75-kb regions spanning 17 S to 25 S ribosomal RNA genes were successfully amplified in a 2X PCR pre-mix containing BLOTTO. Further fidelity assessment of the mCTAB method by PCR analysis with Roundup Ready soybean (RRS) and non-RRS plants showed that the DNA samples prepared alternately from each of two lines were evidently free of cross-contamination. These results demonstrate that the mCTAB method is highly recommended for the rapid detection of transgenes in large numbers of leaf samples from diverse transgenic plants.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.62 no.4
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• pp.198-203
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• 2013

There are conditions that can be unbalanced three phase currents in a large generator by untransposed lines, unbalanced loads, unsymmetrical faults, and open phases. The unbalanced conditions can producing negative sequence components of current that induce two times frequence current in the surface of the rotor, the retaining rings, the slot wedges in the field windings. These rotor currents make the rotor rapidly overheat, so the rotor can cause substantial damage in a very short time. This paper presents the digital negative sequence relay algorithm for unbalanced protection in a generator. The proposed algorithm was tested by using collected current signals on PSCAD/EMTDC considering a hydro turbine based generator control system. It can be seen that the proposed relaying by negative sequence current is useful for detection of unbalanced state of large generator.

• IEMEK Journal of Embedded Systems and Applications
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• v.16 no.6
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• pp.277-283
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• 2021

This paper addresses the problem of vision-based mask filter inspection for mask production systems. Machine learning-based approaches can be considered to solve the problem, but they may not be applicable to mask filter inspection if normal and anomaly mask filter data are not sufficient. In such cases, handcrafted image processing methods have to be considered to solve the problem. In this paper, we propose a hierarchical correlation-based approach that combines handcrafted image processing methods to detect anomaly mask filters. The proposed approach combines image rotation, cropping and resizing, edge detection of mask filter parts, average blurring, and correlation-based decision. The proposed approach was tested and analyzed with real mask filters. The results showed that the proposed approach was able to successfully detect anomalies in mask filters.