• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2000.11a
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• pp.125-128
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• 2000

In this paper, we introduce an algorithm for identification of the Advanced Mountain Methods parameter. It consists of two phases: Phase I and Phase II. In Phase I, a given data space is divided into subspaces based on the density of the given data. In Phase II, we obtain the AMMs parameter $\omega$ by selecting the minimum of variances of subspaces obtained in Phase I. Numerical examples are presented to show the validity of the proposed method.

• Journal of KIISE:Computing Practices and Letters
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• v.16 no.5
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• pp.531-540
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• 2010

In this paper, we present a two-phase shallow semantic parsing method based on a maximum entropy model. The first phase is to recognize semantic arguments, i.e., argument identification. The second phase is to assign appropriate semantic roles to the recognized arguments, i.e., argument classification. Here, the performance of the first phase is crucial for the success of the entire system, because the second phase is performed on the regions recognized at the identification stage. In order to improve performances of the argument identification, we incorporate syntactic knowledge into its pre-processing step. More precisely, boundaries of the immediate clause and the upper clauses of a predicate obtained from clause identification are utilized for reducing the search space. Further, the distance on parse trees from the parent node of a predicate to the parent node of a parse constituent is exploited. Experimental results show that incorporation of syntactic knowledge and the separation of argument identification from the entire procedure enhance performances of the shallow semantic parsing system.

• Korean Journal of Construction Engineering and Management
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• v.4 no.2 s.14
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• pp.109-117
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• 2003

The construction project is largely exposed to much more risk events over the project life cycle due to its complexity and size than the other industries. Therefore, the construction risk management process to identify and response the risk events is not only performing acutely but also proceeding systematically. The risk identification phase in the risk management process is to identify various risk events and define its characteristics. At this phase, the risk identification system is very useful tool to identify every possible risk events in the project. This study shows some problems of the existing risk identification system and proposes the modified risk identification system based on the project phases and the contract bodies, and also suggests partial but more enough detailed risk checklists to be implemented in the actual risk identification phase than any other existing risk breakdown systems to be examined at this study.

• Journal of the Korean Society for Nondestructive Testing
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• v.30 no.6
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• pp.527-538
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• 2010

This paper presents a nondestructive evaluation approach for system identification (SID) of real railway bridges using field vibration test results. First, a multi-phase SID scheme designed on the basis of eigenvalue sensitivity concept is presented. Next, the proposed multi-phase approach is evaluated from field vibration tests on a real railway bridge (Wondongcheon bridge) located in Yangsan, Korea. On the steel girder bridge, a few natural frequencies and mode shapes are experimentally measured under the ambient vibration condition. The corresponding modal parameters are numerically calculated from a three-dimensional finite element (FE) model established for the target bridge. Eigenvalue sensitivities are analyzed for potential model-updating parameters of the FE model. Then, structural subsystems are identified phase-by-phase using the proposed model-updating procedure. Based on model-updating results, a baseline model and a nondestructive evaluation of test bridge are identified.

• Proceedings of the IEEK Conference
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• 1999.06a
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• pp.958-961
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• 1999

A new image encoding and identification scheme is proposed for security verification by using CGH(computer generated hologram), random phase mask, and correlation technique. The encrypted image, which is attached to the security product, is made by multiplying QPH(quadratic phase hologram) using SA(simulated annealing) algorithm with a random phase function. The random phase function plays a role of key when the encrypted image is decrypted. The encrypted image could be optically recovered by 2-f system and automatically verified for personal identification. Simulation results show the proposed method cand be used for the reconstruction and the recognition of the encrypted. Image.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.7 no.6
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• pp.34-41
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• 1993

This paper describes an effort to develop a microcomputer-based parameter identification system for three phase and two phase brushless DC motor. Back EMF equation is derived from back EMF waveform of three phase and two phase brushless DC motor. In this paper, a new identification algorithm for the brushless DC motor parameters by Pasek's technique is de veloped. It is found that Pasek's equation is valid for the brushless DC motor, too. The results obtained clearly shows that it is possible to implement the identification system for the determination of the brushless DC motor parameters. To minimize errors due to the ripple component in the measured armature current, dlgital averaging filter is employed. The whole identification process of signal generation, measuring, parameter determination is fully automated. The use of the pmpased method in the parameter identification system shows that the averaged current curve is in excellent agreement with the estimated current curve. Therefore, this close agreement conf i i the validity of this technique.

• Journal of the Korean Society of Industry Convergence
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• v.4 no.2
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• pp.149-155
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• 2001

The use of primitive cell volume and zero order Laue (ZOLZ) pattern is proposed to identify phase in a complex microstructure. Single convergent beam electron pattern containing higher order Laue zone ring from a nanosized region is sufficient to calculate the primitive cell volume of the phase, while ZOLZ pattern is used to determine the zone axis of the crystal. A computer program is used to screen out possible phases from the value of measured cell volume from convergent beam electron diffraction (CBED) pattern. Indexing of ZOLZ pattern follows in the program to find the zone axis of the identification from a single CBED pattern. An example of the analysis is given from the rapidly solidified $Al-Al_3Ti$ system.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1812-1818
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• 2005

Even though SMA actuators have high power to volume ratio, there exist disadvantages such as hysteresis and saturation. So the model identification for SMA actuators is very difficult. For the qualitative model identification, we described the behavior of SMA actuators using a so-called diagonal model, which can readily expect the turning point of an incomplete phase transformation. For the quantitative model identification, we developed the general dynamics of SMA actuators using the modified Liang's model. Using this dynamics we can describe the hysteresis and the saturation very well. It is also very important to notice that the modified Liang's model maintains a continuous martensite fraction at the change of the phase transformation but the original model cannot.

• Journal of the Earthquake Engineering Society of Korea
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• v.22 no.3
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• pp.201-210
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• 2018

The improvement in computing systems and sensor technologies devotes to conduct data-driven structural health monitoring algorithms for existing civil infrastructures. Despite of the development of techniques, the uncertainty oriented from the measurement results in the discrepancy to the actual structural parameters and let engineers or decision makers hesitate to adopt such techniques. Many studies have shown that the modal identification results can be affected by the uncertainties due to the applied methods and the types of loading. This paper aims to compare the performance of modal identification methods using Structural Modal Identification Toolsuite (SMIT) which has been developed to facilitate multiple identification methods with a user-friendly designed platform. The data fed into SMIT processes three stages for the comprehensive identification including preprocessing, eigenvalue estimation, and post-processing. The seismic and white noise response for shear frame model was obtained from numerical simulation. The identified modal parameters is compared to the actual modal parameters. In order to improve the quality of coherence in identified modal parameters, several hurdles including modal phase collinearity and extended modal amplitude coherence were introduced. Numerical simulation conducted on the 5 dof shear frame model were used to validate the effectiveness of using these parameters.

• Korean Journal of Optics and Photonics
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• v.14 no.4
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• pp.383-391
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• 2003

A new optical security system for the protection of personal identification information is proposed. Personal identification information consisting of a pure face image and an identification number is used for verification and authentication. Image encryption is performed by a fully phase image encryption technique with two random phase masks located in the input and the Fourier plane of 4-f correlator. The personal information, however, can be leaked out in the decryption process. To cope with this possibility, the encrypted image itself is used in the identification process. An encrypted personal identification number is discriminated and recognized by using the proposed MMACE_p (multiplexed MACE_p) filter, and then authenticity of the personal information is verified by correlation of the face image using the optical wavelet matched filter (OWMF). MMACE_p filter is a synthetic filter with four MACE_p (minimum average correlation energy_phase encrypted) filters multiplexed in one filter plane to recognize 10 different encrypted-numbers at a time. OWMF can improve discrimination capability and SNR (signal to noise ratio). Computer simulations confirmed that the proposed security technique can be applied to the protection of personal identification information.