• Journal of the Korean Statistical Society
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• v.24 no.2
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• pp.419-437
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• 1995

Given the specific mean shift outlier model, several standard approaches to obtaining test statistic for outliers are discussed. Each of these is developed in detail for the nonlinear regression model, and each leads to an equivalent distribution. The geometric interpretations of the statistics and accuracy of linear approximation are also presented.

• Journal of the Korean Society for Railway
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• v.13 no.4
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• pp.404-411
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• 2010

Authors conducted a deduction and characteristic calculation of the some parameters using a magnetic equivalent circuit method to verify a basic design result of a rotary-typed small-scaled linear induction motor for a railway transit. In a LIM, it is possible to express the parameters of the magnetic equivalent circuit into a function of the shape of the secondary aluminium plate and the airgap between the LIM primary core and the secondary aluminium plate. It means that the LIM properties can be changed considerably by the shape of the secondary aluminium plate and the airgap between the LIM primary core and the secondary aluminium plate. So, authors analyzed a tendency of changes of the magnetic equivalent circuit parameters and the LIM characteristics by changing of the airgap, the thickness of the secondary aluminium plate and the overhang length and shape of a rotary-typed small-scaled LIM, and accomplished a basic research to develop a real-scaled LIM for a railway transit.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2005.03a
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• pp.437-444
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• 2005

An equivalent linearization technique based on Rayleigh peak distribution for friction damper and brace system (FDBS) under stochastic excitation is proposed. For verification, shaking table test of a small scale 3-story building model with the FDBS is conducted for various slip moment levels. Using experimental result, equivalent linearization of the FDBS is conducted based on Rayleigh peak distribution, which is compared with measured peak distribution. For comparative study, model updating technique is applied based on identified modal properties. Finally, complex modal analysis and time history analysis for the obtained equivalent linear systems are conducted and compared with experimental result.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.06a
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• pp.743-750
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• 2000

This paper presents an equivalent linearization method and application to the equations of motion of a 6 degree-of-freedom PRRS HexaSlide type parallel manipulators which are characterized as the architecture with constant link lengths that are attached to moving sliders on the ground and to a mobile platform. Since dynamic equations of parallel manipulators are complicated and highly nonlinear, control bandwidth, adjustable control gain as well as vibration characteristics cannot be easily found. The proposed equivalent linearization method can be applied over specified workspace as well as on a path of mobile platform. Through an equivalent linearization method, one can easily get a simple linear dynamic model. This linearized dynamic model may be utilized in a simplified computed torque control strategy.

• Proceedings of the KIEE Conference
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• 1997.11a
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• pp.22-24
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• 1997

The 4-pole LHSM was composed of the figure-of-eight shaped 3-phase armature windings. DC field windings, and the segmented secondary with the transverse bar track. The motor was designed on the base of the performance characteristic equations and the equivalent circuit model, with the coefficients of the magnetic shape. These coefficients were computed from the analytical expressions and examined from FEM analysis. The magnetic equivalent circuit of 3-D model of LHSM was obtained. and this concept provided the equivalent models for 2-D FEM analysis. Therefore, the airgap field, the lift and thrust force were calculated and compared with the results of magnetic equivalent circuit method.

• Proceedings of the KIEE Conference
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• 2000.07b
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• pp.981-983
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• 2000

Linear induction motors have static and dynamic end effects due to its finite core length, so that per-phase impedances are asymmetric and the air gap flux distribution is distorted. Because of these points the d-q equivalent circuit model considering both end effects has not been exactly completed. So this paper proposes a characteristic analysis method considering both static and dynamic end effect of the LIM. This method is to utilize asymmetric d-q equivalent circuit model with dynamic end effect coefficient. As a result, it is shown that the simulation results have a good agreement with experimental ones.

• Proceedings of the KIEE Conference
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• 2000.11b
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• pp.268-270
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• 2000

This paper deals with the design of transverse flux linear actuator based on the proposed design procedure. To satisfy requirement specifications, the initial model is designed by the equivalent magnet circuit and then the detailed design is achieved by Finite Element Method(FEM) using the equivalent reluctance 2D model. The effects of the design parameter on the static characteristics are investigated to increase the thrust.

• Proceedings of the KIEE Conference
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• 1995.07a
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• pp.337-339
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• 1995

A Linear Induction Machine(LIM) is the motor which is developed from an rotary induction machine. Usually, the electromagnetic field of an LIM is analyzed by Maxwell's equations. The structure of an LIM is different from a conventional rotary machine, an LIM has some particular characteristics such as the end effects. Hence, the mathematical analysis of an LIM is very complicated and the implementation of the equivalent model is difficult. In this paper, the dynamic equations and the equivalent model of a Double-sided short primary LIM(DLIM) is obtained by the winding function and a d-q theory. The validity of the proposed methodology is verified by numerical analysis.

• Geomechanics and Engineering
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• v.29 no.3
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• pp.219-228
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• 2022

The most widely used parameter to represent rock abrasiveness is the Cerchar abrasivity index (CAI). The CAI value can be applied to predict wear in TBM cutters. It has been extensively demonstrated that the CAI is affected significantly by cementation degree, strength, and amount of abrasive minerals, i.e., the quartz content or equivalent quartz content in rocks. The relationship between the properties of rocks and the CAI is investigated in this study. A database comprising 223 observations that includes rock types, uniaxial compressive strengths, Brazilian tensile strengths, equivalent quartz contents, quartz contents, brittleness indices, and CAIs is constructed. A linear model is developed by selecting independent variables while considering multicollinearity after performing multiple regression analyses. Machine learning-based regression methods including support vector regression, regression tree regression, k-nearest neighbors regression, random forest regression, and artificial neural network regression are used in addition to multiple linear regression. The results of the random forest regression model show that it yields the best prediction performance.

• Journal of Korean Association for Spatial Structures
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• v.6 no.2 s.20
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• pp.115-121
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• 2006

In recent years vibration control damper made of low yield point steel is expected to play an important role in controlling structural vibration induced earthquake and wind. But their dynamic characteristics and energy dissipation effects on the whole structure model are not clarified. In this paper, firstly, we presents the results of cyclic tests on low yield steel dampers. Secondly, forced vibration tests on existence three stories steel structure model with low yield point steel dampers are presented. Lastly, it is estimated energy amount which is dissipated through the hysteresis dampers by using two types of analytical models, hysteresis model and equivalent linear model.