• Journal of the Korean Society for information Management
• /
• v.16 no.4
• /
• pp.53-74
• /
• 1999

This paper describes concept mapping techniques for eliciting and representing knowledge. Concept mapping techniques range from very informal to very formal. Informal concept mapping techniques are usually very easy to use and understand for humans, but not for computers. Formal concept mapping techniques are computational, but humans usually find them hard to understand and use. A knowledge acquisition and representation tools which handle both kinds, and the transition from informal to formal, would be very useful. It is proposed that concept maps be regarded as basic components of any knowledge-based system, complementing text and image with formal and informl active diagrams.

• The Journal of the Acoustical Society of Korea
• /
• v.23 no.2
• /
• pp.125-133
• /
• 2004

Most of the way shape estimation method using reference sources assume that the reference sources are in the farfield. That is, the reference sources are assumed to be far from the array. However, in applications of the array with reference sources, the reference sources are not far from the way, so that in practical ocean environments, the conventional method using farfield source model fail to estimate the positions of the hydrophones. In this paper, based on the nearfield source model, a subspace-based array shape estimation method was proposed. In the proposed method, nearfield reference source is modeled using the differential time delay at each hydrophone, and nearfield parameters are derived. Using these parameters, a subspace-based array shape estimation method that generalizes the existing farfield subspace fitting method which can work regardless of the range of the source is proposed. The Cramer-Rao lower bound for the proposed method is investigated. The results of the numerical experiments indicate that the proposed method performs well in estimating the shape of a perturbed way regardless of the ranges of the reference sources.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.26 no.6
• /
• pp.505-510
• /
• 2016

This paper presents a searching method of corresponding points robust to rotational error for scan-matching used for SLAM(Simultaneous Localization and Mapping) in mobile robot. A differential driving mechanism is one of the most popular type for mobile robot. For driving curved path, this type controls the velocities of each two wheels independently. This case increases a wheel slip of the mobile robot more than the case of straight path driving. And this is the reason of a drifting problem. To handle this problem and improves the performance of scan-matching, this paper proposes a searching method of corresponding points using extraction of a closest point based on rotational radius of the mobile robot. To verify the proposed method, the experiment was conducted using LRF(Laser Range Finder). Then the proposed method is compared with an existing method, which is an existing method based on euclidian closest point. The result of our study reflects that the proposed method can improve the performance of searching corresponding points.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.26 no.7
• /
• pp.996-1003
• /
• 2022

In this paper, we present a new method for determining the scan line and range for vision-based 1-D barcode recognition. This is a study on how to detect valid barcode representative points and directions by applying the DBSCAN clustering method based on block HOG (histogram of gradient) and determine scan lines and barcode crosslines based on this. In this paper, the minimum and maximum search techniques were applied to determine the cross-line range of barcodes based on the obtained scan lines. This can be applied regardless of the barcode size. This technique enables barcode recognition even by detecting only a partial area of the barcode, and does not require rotation to read the code after detecting the barcode area. In addition, it is possible to detect barcodes of various sizes. Various experimental results are presented to evaluate the performance of the proposed technique in this paper.

• Journal of Digital Convergence
• /
• v.12 no.1
• /
• pp.339-345
• /
• 2014

This study has a purpose that improves efficiency of energy management and adaptation followed by movement of node better than the various early studied routing techniques. The purpose of this paper is the technique that uses RSSI value and location of sensor that is received by each sensor node to routing. This sduty does not save node information of 1-hop distance. And it solves energy-inefficient traffic problem that happens during data exchange process for middle node selection in close range multi hop transmission technique. The routing protocol technique that is proposed in this study selects a node relevant to the range of transmission which is set for RSSI value that is received by each node and selects the closest node as a middle node followed by location data. Therefore, it is for not exhaustion of node's energy by managing energy efficiently and cutting data transmission consuming until the destination node.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.15 no.4
• /
• pp.957-964
• /
• 2011

The image stabilization is the procedure of stabilizing the blurred image with image processing method. Due to easy detection of global motion, PA(Projection algorithm) based on digital image stabilization has been studied by many researchers. PA has the advantage of easy implementation and low complexity, but in the case of serious rotational motion the accuracy of the algorithm will be cut down because of its fixed exploring range, and, on the other hand, if extending the exploring range, the block for detecting motion will become small, then we cannot detect correct global motion. In this paper, to overcome the drawback of conventional PA, an Iterative Projection Algorithm (IPA) is proposed, which improved the correctness of global motion by detecting global motion with detecting block which is appropriate to different extent of motion. With IPA, in the case of processing 1000 continual frames shot in automobile, compared with conventional algorithm and other detecting range, the results of PSNR is improved 6.8% at least, and 28.9% at the most.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.39 no.4
• /
• pp.354-361
• /
• 2011

In this paper, an efficient defense strategy of single naval ship using short range anti-air missiles against the threat of multiple anti-ship missiles is suggested. The defense logic is based on the estimated future trajectory of anti-ship missiles by using current radar information. The logic is designed to maximize the range of interception of anti-ship missiles so that the chance of interception can be increased although the prior tries turn out to be fail. Basically, the decision making for the allocation of a defense missile is achieved by comparing the total kill probability and the estimated intercepting point. Performance of the proposed logic is investigated by nonlinear planar numerical simulations.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.37 no.3
• /
• pp.248-254
• /
• 2009

The use of evolutionary algorithm is limited in the field of aerodynamics, mainly because the population-based search algorithm requires excessive CPU time. In this paper a coupling method with adaptive range genetic algorithm for floating point and back-propagation neural network is proposed to efficiently obtain a converged solution. As a result, it is shown that a reduction of 14% and 33% respectively in wave drag and its consumed time can be achieved by the new method.

• Journal of Satellite, Information and Communications
• /
• v.9 no.2
• /
• pp.38-44
• /
• 2014

This paper presents design of a FMCW (Frequency Modulated Continuous Wave) level meter as well as simulation result of the designed system. The system is designed to measure maximum range of 20m since FMCW radar can be used for measuring short range distance. The distance is measured by analyzing the beat signal which is generated as result of mixing transmitting signal with the reflected received signal. The Fast Fourier Transform is applied to analyze the beat signal for calculating the displacement and Zoom FFT technique is used to minimize measurement error as well as increase the resolution of the measurement. The resolution of the measurement of the designed system in this paper is 2.2mm and bandwidth of 1.024GHz is used for simulation. Thus the simulation results are analyzed and compared in various conditions in order to get a comprehensive idea of frequency resolution and displacement resolution.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.33 no.1
• /
• pp.61-70
• /
• 2013

This paper presents the response calibration method based on quality control range, which is established from the concept and method of statistical quality control for natural frequency ratio and response ratio. To this end, statistical analysis including descriptive statistics analysis, normality test, ANOVA were performed for response characteristics obtained from loading tests and structural analysis for more than hundred and thirty well-conditioned bridges. Suggested method is based on real structural integrity evaluation case studies and statistical quality control approach, in this respect it is expected to provide scientific criteria and systematic procedure for response calibration and load carrying capacity assessment.