• Proceedings of the KIPE Conference
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• 2007.07a
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• pp.92-94
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• 2007

In order to analyze voltage, current, electrical power, harmonics and so on of electrical load equipments, electrical power analysis by real measurement rather than mathematical modeling is necessary, and plan of countermeasure for efficient management, energy frugality and accident prevention of electrical equipments using it is possible. Especially, electrical power analysis by real measurement is indispensable in order to consider countermove of harmonic occurred by nonlinear load. So, in this paper, we developed DSP(Digital Signal Processor) based low price date aquisition system, and verified it's ability by performing measurement and analysis of electrical power and harmonic in the real power system.

• Structural Monitoring and Maintenance
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• v.10 no.4
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• pp.361-379
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• 2023

In cable structure maintenance, particularly for cable-stayed bridges, cable safety assessment relies on estimating cable tension. Conventionally, in Japan, cable tension is estimated from the natural frequencies of the cable using the higher-order vibration method. In recent years, dampers have been installed on cables to reduce cable vibrations. Because the higher-order vibration method is a method for damper-free cables, the damper must be removed to measure the natural frequencies of a cable without a damper. However, cables on some cable-stayed bridges have two dampers: one on the girder side and another on the tower side. Notably, removing and reinstalling the damper on the tower side are considerably more time- and labor-intensive. This paper introduces a tension estimation method for cables with two dampers, using natural frequencies. The proposed method was validated through numerical simulation and experiment. In the numerical tests, without measurement error in the natural frequencies, the maximum estimation error among 100 models was 3.3%. With measurement error of 2%, the average estimation error was within 5%, with a maximum error of 9%. The proposed method has high accuracy because the higher-order vibration method for a damper-free cable still has an estimation error of 5%. The experimental verification emphasizes the importance of accurate damper modeling, highlighting potential discrepancies between existing damper design formula and actual damper behavior. By revising the damper formula, the proposed method achieved accurate cable tension estimation, with a maximum estimation error of approximately 10%.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.67-69
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• 2006

Capacitance and loss values of pentacene MIS capacitors with different thicknesses are measured as a function of frequency for the modeling of the devices. The equivalent circuit for the ideal MIS capacitor is adopted to model the obtained admittance, so the values of $C_i,\;C_d,\;C_b$, and $R_b$ are determined for each pentacene thickness. In the loss curve, broader loss peaks are observed in measurement than the modeling results regardless of the pentacene thickness. By considering the effects of dispersive charge transport in bulk semiconductor, more accurate modeling results are obtained.

• Proceedings of the KIEE Conference
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• 2004.07c
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• pp.1876-1878
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• 2004

A systematic approach of measurement, modeling and analysis of grounding system impedance is presented. The measurement and analysis system of ground impedance is based on a computer aided technique. The ground impedances of the ground rod are considerably dependent on the frequency. The ground impedance is mainly resistive in the frequency range of 3-20 kHz. At higher frequencies, the reactive components of the ground impedances are no longer negligible and the inductance of the ground rod was found to be the core factor deciding the ground impedance. As a consequence, the equivalent circuit model based on the measured data was proposed, and the calculated results were in approximately agreement with the measured data.

• Journal of Sensor Science and Technology
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• v.13 no.5
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• pp.342-349
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• 2004

SK (SPR Kinds) index, which can categorize the complicated measurement methods of surface plasmon resonance by simple method, has been proposed and verified. SK index is composed of three digits, where each digit presents the type of immobilized ligand, the type of illumination and the kinds of varying parameter, sequentially. The measurement method of (33#) series among SK indices shows the possibility of the multi-sensing capability, by which the response of 2-dimensional array of immobilized ligands can be detected simultaneously. The proposed possibility of multi-sensing capability has been verified by the modeling that is based on Fresnel reflection model.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.12
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• pp.81-88
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• 1998

Measurement and inspection of freeform surfaces are required in reverse design processes. In the case of surface measurement using a touch probe, probe radius compensation affects measuring accuracy. But current industrial practice depends upon an operator's experience to compensate for probe radius. In this paper, an on-the-machine measuring and inspection system for freeform surfaces is studied. Probe radius compensation methodology is investigated by modeling of B-spline surfaces based on digitized data. The accuracy and reliability of the developed system is verified through various kinds of numerical simulations and on-the-machine experiments.

• Proceedings of the Korea Society for Simulation Conference
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• 2005.05a
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• pp.154-159
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• 2005

In this paper, We used the microphone unlike existing urodynamic inspection which diagnoses the LUTS(lower urinary tract symptoms) and proposed sound measurement the method which the urination happens and apply at a blockade diagnosis. To analyze the blockade degree, We made the experiment set to modeling the Lower Urinry System of the human body and made the microphone of the stethoscope form for the measurement of the urinary sound which the urination happens. We used PC for the analysis of the urinary sound to be measured and implemented the analysis program to use the MATLAB. Hereafter, An analysis result usage, The Practical use will be possible as one of new inspection methods's.

• The Journal of Information Technology
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• v.7 no.3
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• pp.1-10
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• 2004

Considerable efforts has been recently devoted to the determination of accurate channel models for the Power Line environment, both for the indoor and outdoor cases. The common denominator and limitation of the known and previously published models is the particular type of approach followed. In this paper is concerned with a power line channel modeling for the more fast and efficiently power line communication experiment. A capacitor load channel simulator is a essential equipment in the power line modem development for indoor network. We accomplished a channel modelling by the frequency response method about the total 224 capacitor load cases. On the basis of this measurement modeling it is here revealed that the PLC is a more deterministic media that commonly believed.

• Journal of the Korea Computer Industry Society
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• v.5 no.9
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• pp.993-1004
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• 2004

We propose the method for kinematic and dynamic modeling and Path-tracking of four-wheeled mobile robots with 2 d.o.f having the limited drive-torques. Controllability of wheeled-mobile robots is revealed by using the kinematic model. Instantaneously coincident coordinate system, force/torque propagation and Newton's equilibrium law are used to induce the dynamic model. When drive-torques generated by inverse dynamics exceed the limitation, we make wheeled-mobile robots follow the reference path by modifying the planned reference trajectory with time-scaling. The controller is introduced to compensate for error owing to modeling uncertainty and measurement noise. And simulation results prove that the method proposed by this paper is efficient.

• Journal of the Korean Society of Safety
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• v.32 no.2
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• pp.7-13
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• 2017

An experimental study was conducted to identify the quantitative measurement bias for the bare-bead thermocouple (TC), which was widely used for measuring temperature in fire experiments. To this end, an apparatus could be controlled individually gas flow rate, preheating temperature and incident radiative heat flux was developed to simulate the thermal environments of fire. A relative measurement bias of bare-bead TC was evaluated with the comparison of double-shield aspirated TC. As a result, the relative measurement bias of bare-bead TC was gradually increased with the increase in radiative heat flux with constant gas temperature. The relative bias was also significantly increased with the decrease in gas temperature. Quantitatively, at the gas temperature of $20^{\circ}C$, the bare-bead TC had the relative bias of approximately 400% with the radiative heat flux of $20kW/m^2$ corresponding to thermal radiation level of the flashover. The present study was intend to provide fire researchers with methodologies for the reanalyses of temperature measured using bare-bead TC, radiation corrections, and validation of fire modeling.