• Convergence Security Journal
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• v.6 no.4
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• pp.75-82
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• 2006

Internet worm gives various while we paralyze the network and flow the information out damages. In this paper, I suggest the method to prevent this. This method detect internet worm in PC first. and present the method to do an automatic confrontation. This method detect a traffic foundation network scanning of internet worm which is the feature and accomplish the confrontation. This method stop the process to be infected at the internet worm and prevent that traffic is flowed out to the outside. and This method isolate the execution file to be infected at the internet worm and move at a specific location for organizing at the postmortem so that we could accomplish the investigation about internet worm. Such method is useful to the radiation detection indication and computation of unknown internet worm. therefore, Stable network operation is possible through this method.

• Structural Engineering and Mechanics
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• v.58 no.1
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• pp.163-179
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• 2016

The Cuckoo search (CS) algorithm is a simple and efficient global optimization algorithm and it has been applied to figure out large range of real-world optimization problem. In this paper, a new formula is introduced to the discovering probability process to improve the convergence rate and the Tournament Selection Strategy is adopted to enhance global search ability of the certain algorithm. Then an approach for structural damage identification based on modified Cuckoo search (MCS) is presented. Meanwhile, we take frequency residual error and the modal assurance criterion (MAC) as indexes of damage detection in view of the crack damage, and the MCS algorithm is utilized to identifying the structural damage. A simply supported beam and a 31-bar truss are studied as numerical example to illustrate the correctness and efficiency of the propose method. Besides, a laboratory work is also conducted to further verification. Studies show that, the proposed method can judge the damage location and degree of structures more accurately than its counterpart even under measurement noise, which demonstrates the MCS algorithm has a higher damage diagnosis precision.

• Journal of Sensor Science and Technology
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• v.27 no.4
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• pp.216-220
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• 2018

In this paper, we present visual sensing techniques that can be used to teach a robot using a laser pointer. The light spot of an off-the-shelf laser pointer is detected and its movement is tracked on consecutive images of a camera. The three-dimensional position of the spot is calculated using stereo cameras. The light spot on the image is detected based on its color, brightness, and shape. The detection results in a binary image, and morphological processing steps are performed on the image to refine the detection. The movement of the laser spot is measured using two methods. The first is a simple method of specifying the region of interest (ROI) centered at the current location of the light spot and finding the spot within the ROI on the next image. It is assumed that the movement of the spot is not large on two consecutive images. The second method is using a Kalman filter, which has been widely employed in trajectory estimation problems. In our simulation study of various cases, Kalman filtering shows better results mostly. However, there is a problem of fitting the system model of the filter to the pattern of the spot movement.

• Smart Structures and Systems
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• v.19 no.5
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• pp.513-521
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• 2017

The purpose of this paper is to study the capabilities of the impulse response method in length and flaw detecting for concrete piles and provide a suggested method to find small-size flaws in piles. In this work, wavelet transform is used to decompose the recorded time domain signal into a series of levels. These levels are narrowband, so the mix of different dominant bandwidths can be avoided. In this study, the impulse response method is used to analyze the signal obtained from the wavelet transform to improve the judgment of the flaw signal so as to detect the flaw location. This study provides a new way of thinking in non-destructive testing detection. The results show that the length of a pile is easy to be detected in the traditional reflection time or frequency domain method. However, the small flaws within pile are difficult to be found using these methods. The proposed approach in this paper is able to greatly improve the results of small-size flaw detection within piles by reducing the effects of any noise and clarifying the signal in the frequency domains.

• Proceedings of the Korea Contents Association Conference
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• 2005.11a
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• pp.480-484
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• 2005

In this paper, the multiwatermarking method to make it possible to the authentication, modification detection and copyright protection of the digital image was proposed. After the original image is transformed by the DWT(Discrete Wavelet Transform), the encrypted watermark information is embedded into the LSB(Least Significant Bit) of LL band on the low frequence domain for authenticating and detecting modified position in the image. And watermark information is embedded by exchanging the wavelet coefficient for the copyright protection. Thereby, we can authenticate the modification and detect the modified location by extracting the values of LSB on the low frequence domain. And we can perceive the copyright information of original image by extracting the embedded watermark on the high frequence domain.

• Journal of the Korean Institute of Intelligent Systems
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• v.20 no.1
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• pp.60-65
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• 2010

This paper describes the results of 2D mapping, feature detection and matching to create the surrounding environment in the mounted stereo camera on Mobile robot. Extract method of image's feature in real-time processing for quick operation uses the edge detection and Sum of Absolute Difference(SAD), stereo matching technique can be obtained through the correlation coefficient. To estimate the location of a mobile robot using ZigBee beacon and encoders mounted on the robot is estimated by Kalman filter. In addition, the merged gyro scope to measure compass is possible to generate map during mobile robot is moving. The Simultaneous Localization and Mapping (SLAM) of mobile robot technology with an intelligent robot can be applied efficiently in human life would be based.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.78-81
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• 2012

In this paper, we proposed the new vehicle license plates detection method which is available in a various fields, including vehicle access control, illegal parking and speeding vehicle crack down. First, we binarize an image by using difference of gaussian filter to find a sequence of numbers of plates. Second, we determine the plate region by labeling repeatedly using the morphological characteristics of the plates. Finally, we use a projective transformation for correcting the distortion that occurs because of the camera or the location of the vehicle.

• The Transactions of the Korea Information Processing Society
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• v.5 no.5
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• pp.1367-1376
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• 1998

In this paper we propose an real time marker detection algorithm for motion analysis both in 2 dimensions and 3 dimensions with CCD camera and rfame grabber only which has no image processor. The main algorithm consists of the following 3 algorithms; 1) the tracing algorithm that makes it possible to predict the expected marker location by narrowing the searching boundary, 2) the searching algorithm that detects the marker in the expected boundary using Ad-hoc previous screen search technique, tornado search method rotate diagonal search method search technique, 3) the algorithm that finds the central point of the detected marker. We try to narrow the searching boundary for real time processing. Also, it is able to find the central point of the detected marker much faster than typical contour tracing algorithm.

• The Journal of the Korea Contents Association
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• v.6 no.1
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• pp.170-178
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• 2006

In this paper, the hybrid-watermarking method to make it possible to the authentication, modification detection and copyright protection of the digital image was proposed. After the original image is transformed by the DWT(Discrete Wavelet Transform), the encrypted watermark information is embedded into the LSB(Least Significant Bit) of LL band on the low frequence domain for authenticating and detecting modified position in the image. And watermark information is embedded by exchanging the wavelet coefficient for the copyright protection. Thereby, we can authenticate the modification and detect the modified location by extracting the values of LSB on the low frequence domain. And we can perceive the copyright information of original image by extracting the embedded watermark on the high frequence domain.

• Journal of Biomedical Engineering Research
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• v.29 no.5
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• pp.384-391
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• 2008

For use in the guide system for the people who are visually impaired, an obstacle searching device using synchronous ultrasonic wave emission was proposed and developed. Generally, the conventional obstacle detection methods use the ultrasonic distance measuring device with successive scan method. However, the scan method causes a theoretical error and it couldn't estimate accurate obstacle distances. The proposed synchronous firing method use the plural number of ultrasonic sensors which emit ultrasonic wave simultaneously and estimate the distance to the closest obstacle relatively accurately. We analytically analyzed the errors of the conventional and proposed methods and compared the quantitative differences of the errors. The differences verified by obstacle search experiments. Using the proposed ultrasonic wave synchronous firing method, 3 dimensional obstacle location estimating device was designed and implemented. The results of the 3 dimensional obstacle detecting experiments showed the proposed method had good performances and it would be sufficiently use in the guide system for the people who are visually impaired.