• Journal of the Korean Magnetics Society
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• v.18 no.6
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• pp.221-224
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• 2008

This paper describes the equivalent dipole modeling method utilizing a singular value decomposition technique from analysis data by the FNREMUS Detailled Modeller software based on BEM which can predict the underwater electric field signal due to a galvanic corrosion phenomenon on a naval vessel. The proposed dipole modeling method was successfully verified in good agreement with predicted BEM data at 30 m depths through the comparison of average differences. The proposed dipole modelling method can be effectively used in the prediction and analysis of static electric field signature distributions generated from a naval vessel at any different depths.

• The Journal of Engineering Geology
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• v.31 no.4
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• pp.533-540
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• 2021

Gravity field analysis and density modeling were performed to evaluate the internal state of the rock mass, which is the cause of cut slope collapse. The shape of the weathered zone and the depth of basement could be confirmed from the complete Bouguer anomaly and density model. The basement depth at the center of the cut slope calculated using the Euler deconvolution inverse method is 30 m, which is about 10 m deeper than the surrounding area. In addition, the depth of basement and the thickness of the weathered zone are similar to the boundary between low resistivity and high resistivity in dipole-dipole survey. From the study results, gravity field analysis and density modeling recognizes the internal state of the rock slope and can be used for slope safety analysis, and is particularly suitable as a method to determine the shape of weathered zones in interpreting the safety of cut slopes

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1082-1087
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• 2003

In this paper, we address the development of magnetic levitation positioning system. This planar magnetic levitator employs four permanent magnet liner motors. Each motor generates vertical force for suspension against gravity, as well as horizontal force for drive levitation object called a platen This stage can generate six degrees of freedom motion by the vertical and horizontal force. We derived the mechanical dynamics equation using lagrangian method and used coenergy to express an electromagnetic force. We proposed control algorithm for the position and posture control from its initial value to its desired value using sliding mode control. Some simulation result is provided to verify the effectiveness of the proposed control scheme.

• Journal of Korean Society for Quality Management
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• v.33 no.3
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• pp.59-70
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• 2005

The purpose of this research is to identify the impact of trust on user acceptance of mobile banking and to identify if causalities among these factors are different between Internet and mobile banking. To test this model, this research applies the technology acceptance model(TAM) that incorporates trust. Additionally, this research use structural equation modeling to test the model and examine cross-group differences using a multi-group comparison method. The empirical results indicate that all path is significant expect the path from trust to intention to use. The results of a multi-group comparison test indicated that the path from trust to attitude, from trust to intention to use, from perceived usefulness to attitude and from perceived to intention to use are different between Internet and mobile banking.

• Structural Engineering and Mechanics
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• v.6 no.5
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• pp.473-484
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• 1998

The first and second moments of response variables for SDOF systems with hysteretic nonlinearity are obtained by a direct linearization procedure. This adaptation in the implementation of well-known statistical linearization methods, provides concise, model-independent linearization coefficients that are well-suited for numerical solution. The method may be applied to systems which incorporate any hysteresis model governed by a differential constitutive equation, and may be used for zero or non-zero mean random vibration. The implementation eliminates the effort of analytically deriving specific linearization coefficients for new hysteresis models. In doing so, the procedure of stochastic analysis is made independent from the task of physical modeling of hysteretic systems. In this study, systems with three different hysteresis models are analyzed under various zero and non-zero mean Gaussian White noise inputs. Results are shown to be in agreement with previous linearization studies and Monte Carlo Simulation.

• ETRI Journal
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• v.34 no.4
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• pp.536-541
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• 2012

This paper aims to extend the transmission line matrix method with a hybrid symmetrical condensed node (HSCN) to model ferrite media in the time domain. To take into account the anisotropy and dispersive properties of ferrite media, equivalent current sources are incorporated into supplementary stubs of the original HSCN. The scattering matrix of the proposed HSCN is provided, and the validity of this approach is demonstrated for both transversely and longitudinally magnetized ferrites. Agreement is achieved between the results of this approach and those of the theoretical and the finite-difference time-domain method.

• Proceedings of the Korean Geotechical Society Conference
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• 2001.03a
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• pp.363-370
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• 2001

A computationally efficient algorithm to analyze a group pile behavior is proposed by consideration of both soil-pile and pile-cap interactions. Using toad transfer method the nonlinear characteristics of the soil-pile interaction for a single pile is modeled by piecewise linear soil springs (p-y, t-z, and q-z curves). Beam-column method, one of the most practical approaches, is used for numerical modeling of the soil-pile system. In addition to the group effect resulting from the soil-pile-soil interaction, for a more realistic analysis it is essential to consider the effect of pile-cap interaction including geometric configuration of the piles in a group and conectivity conditions between piles and the cap. This paper mainly focuses on the pile-cap interaction and the development of a rational numerical procedure of its incorporation with the beam-column method.

• Proceedings of the KIPE Conference
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• 2003.07b
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• pp.602-605
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• 2003

분산전원용 계통연계 인버터가 효율적인 분산전원으로 사용되기 위해서는 기존 계통과 협조 운전이 필요하다. 따라서 전류제어 외에 무효전력의 제어, 계통과 연계시의 PLL 제어, 단독운전 방지 제어 등의 다양한 기능이 필요하다. 그러나 단상 시스템의 경우, 3상 시스템과 달리 교류전력을 다뤄야 하므로, 제어 시 위상 지연이 발생하게 되고 무효전력을 제어하기 어려운 문제점등이 발생된다 따라서 본 논문에서는 이러한 문제점을 해결하기 위해 dq 모델을 단상시스템에 적용하여 단상 제어의 문제점을 보완하였다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.11
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• pp.4556-4572
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• 2015

Dynamic texture (DT) recognition is a challenging problem in numerous applications. In this study, we propose a new algorithm for DT recognition based on group sparsity structure in conjunction with chaotic feature vector. Bag-of-words model is used to represent each video as a histogram of the chaotic feature vector, which is proposed to capture self-similarity property of the pixel intensity series. The recognition problem is then cast to a group sparsity model, which can be efficiently optimized through alternating direction method of multiplier algorithm. Experimental results show that the proposed method exhibited the best performance among several well-known DT modeling techniques.

• Journal of Hydrospace Technology
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• v.2 no.1
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• pp.18-26
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• 1996

It is normal practice to consider bending wave modes only, when one applies SEA (Statistical Energy Analysis) to ship structures because of complexities in SEA modeling and evaluation of coupling loss factors for inplane modes. According to the result of Tratch[1], the inplane wave modes becomes important for the analysis of a foundation structure as the distance from the source and receiver increases. In this paper, the effect of inplane wave modes on structure-borne noise propagation in ship structures is presented. It is shown that the inplane wave could increase the noise level more than 10 dB compared with the results without inplane wave modes at high frequency bands for compartments far from the source location.