• Computational Structural Engineering
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• v.8 no.3
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• pp.103-111
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• 1995

Evaluating nonlinear response of a MDOF system under dynamic stochastic loads such as seismic excitation usually requires excessive computational efforts. To alleviate this computational difficulty, an approximation is developed in which the MDOF inelastic system is replaced by a simple nonlinear equivalent system(ENS).Me ENS retains the most important properties of the original system such as dynamic characteristics of the first two modes and the global yielding behavior of the MDOF system. The system response is described by the maximum global(building) and local(interstory) drifts. The equivalency is achieved by two response scaling factors, a global response scaling factor R/sub G/, and a local response scaling factor R/sub L/, applied to the responses of the ENS to match those of the original MDOF system. These response scaling factors are obtained as functions of ductility and mass participation factors of the first two modes of structures by extensive regression analyses based on results of responses of the MDOF system and the ENS to actual ground accelerations recorded in past earthquakes. To develop the ENS with two response scaling factors, Special Moment Resisting Steel Frames are considered. Then, these response scaling factors are applied to the response of ENS to obtain the nonlinear response of MDOF system.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1998.06a
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• pp.51-56
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• 1998

In this paper, we analyze the effects of scaling factors on the performance of a fuzzy logic controller(FLC). The quantitative relation between input and output variables of FLC is obtained by using a qualsi-linear fuzzy model, and an approximate transfer function of FLC is dervied from the comparison of it with the conventional PID controller. Then we analyze in detail the effects of scaling factor using this approximate transfer function and root locus method. Also we suggest an on-line tuning method for scaling factors which employs an sample performance function and a variable reference for tuning index.

• Proceedings of the KIEE Conference
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• 1995.07b
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• pp.717-719
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• 1995

In this paper, we analyze the effects of scaling factors on the performance of a fuzzy controller and propose the tuning method for them. The quantitative relation between input and output variables of a fuzzy controller is obtained by using a quasi-linear fuzzy model. An approximate transfer function of a fuzzy controller is derived from the comparison a fuzzy controller with the conventional PID controller. We analyze the effects of scaling factor using this approximate transfer function and propose a fuzzy tuning method based on that of Maeda et al[4].

• Proceedings of the KIEE Conference
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• 1996.07b
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• pp.990-992
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• 1996

The design of I/O scaling factors for fuzzy controller system is proposed in this paper. The proposed method is for nonlinear input scaling factor and variable output scaling factor. The fuzzy controller is evaluated by computer simulation on the 1st order process and 2nd order process. Simulation results showed robust characteristics for variable reference signal.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.9
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• pp.1618-1623
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• 2008

In this paper, a new design method for IMC-PID that adds a phase scaling factor of system identifications to the standard IMC-PID controller as a control parameter is proposed. Based on analytically derived frequency properties such as gain and phase margins, this tuning rule is an optimal control method determining the optimum values of controlling factors to minimize the cost function, integral error criterion of the step response in time domain, in the constraints of design parameters to guarantee qualified frequency design specifications. The proposed controller improves existing single-parameter design methods of IMC-PID in the inflexibility problem to be able to consider various design specifications. Its effectiveness is examined by a simulation example, where a comparison of the performances obtained with the proposed tuning rule and with other common tuning rules is shown.

• The Journal of the Acoustical Society of Korea
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• v.3 no.1
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• pp.16-24
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• 1984

The objective data and subjective data correlated in order to rate sound quality of loudspeaker system and these data were analyzed by the Factor Analysis and Multi-Dimensioinal Scaling. The dimensions yielded Factor Analysis were interpreted as "Contrast", "Metallic", "Rich", "Present" and their relation to physical variables were explored by studying the positions of loudspeaker systems in the respective dimension. When the subjective similarity degree of loudspeaker systems was compared with the objective similarity degree of loudspeaker systems by Multi-Dimensional Scaling, the similarity degree of sound pressure response in the listening room closely coincided with the subjective similarity degree regardless of sound source. This result implies the necessity of measurements taken not only in an anechoic room but also in a listening room in order to rate sound quality of loudspeaker systems.

• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.1
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• pp.59-66
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• 2021

The earthquakes are the natural disasters that can cause the most serious damage to civil structures. Therefore, various studies are being conducted to secure the safety of structures against earthquakes. Most studies on the safety or mechanism of civil structures during earthquakes are being conducted based on lab scale test, because real structure tests are impossible when considering the scale of civil structures. The scaling factor proposed by Iai is mainly cited, but when applying the scaling factor proposed by Iai, there are many difficulties in selecting the structural members necessary for the production of the lab scale model. This is because when applying the scaling factor proposed by Iai, the scaling factor must be applied to the elastic modulus, which is the material property of the structure. Therefore, a new method based on Iai's 's similarity law for determining scale factor is applied in this study where the material property of real structure is same as that of lab-scale model. Through the results of this study, it is considered that the characteristics of the structure calculated through the lab scale model test can more accurately reflect the characteristics of the real structure.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2003.11a
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• pp.322-327
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• 2003

It is important to know the accurate radionuclide inventory of radioactive waste for the reliable management. However, estimation of radionuclide concentrations in drummed radioactive waste is difficult and unreliable because of difficulties of direct detection, high cost, and radiation exposure of sampling personnel. In order to overcome these difficulties, scaling factors (SFs) have been used to assess the activities of radionuclides that could not be directly analyzed. A radionuclide assay system has been operated at KORI site since 1996 and consolidated scaling factor method has played a dominant role in determination of radionuclides concentrations. However, some problems are still remained such as uncertainty of estimated scaling factor values, inaccuracy of analyzed sample values, and disparity between the actual and ideal correlation pairs and the others. Therefore, it needs to improve the accuracy of scaling factor values. The scope of this paper is focused on the improvement of accuracy and representativeness of calculated scaling factor values based on statistical techniques. For the selection of reliable activity determination method, the accuracy of estimated SF values for each activity determination method is compared. From the comparison of each activity determination methods, it is recommended that SF determination method should be changed from the arithmetic mean to the geometrical mean for more reliable estimation of radionuclide activity. Arithmetic mean method and geometric mean method are compared based on the data set in KORI system.

• Proceedings of the Korean Nuclear Society Conference
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• 1995.05b
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• pp.833-838
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• 1995

This study presents a method to predict plant-specific and operational history dependent scaling factors. Realistic and detailed approaches are taken to find scaling factors at reactor coolant. This approach begins with fission product release mechanisms and fundamental release properties of fuel-source nuclide such as fission product and transuranic nuclide. Scaling factors at various waste streams are derived from the predicted reactor coolant scaling factors with the use of radionuclide retention and build up model. This model makes use of radioactive material balance within the radioactive waste processing systems. According to input parameters of plant operation history, scaling factors predicted at reactor coolant and waste streams are well brought out the effects of plant operation history.

• Journal of Korean society of Dental Hygiene
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• v.17 no.3
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• pp.539-551
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• 2017

Objectives: The purpose of this study was to investigate the changes in factors on unmet dental scaling rate before and after the national health insurance. Methods: This study used the $2^{nd}$ data from the Community Health Survey. The study participants numbered 209,341 in 2011 and 219,517 in 2013.The average age was $51{\pm}17$ in 2011 and $52{\pm}17$ in 2013. Data were analyzed by descriptive statistics, chi -squared test and logistic regression using SPSS 23.0. Results: The scaling experienced rate of Korean adults has fallen by 3.5% from 66% to 69.5%. Logistic regression analysis showed that 2.7 times more 'people who were educated at elementary school level or lower' did not use dental scaling compared to higher educated children. Agriculture, forestry and fisheries workers did not use scaling at 2.0 times. Local residents with an income of less than one million won did not use 1.7times scaling. Local residents of 'no private insurance' did not use scaling at 1.5 times. In the case of the predisposing factors, the 20s had less than 1.8 times scaling compared to 50s. In the case of needs factor, local residents who experienced 'bad oral health status' and 'dental calculus' were treated scaling 1.3 times less compared to people with good oral health status and normal periodontal symptoms. Conclusions: In Korea, local residents are less frequently treated scaling due to enabling factors such as accessibility. In addition, predisposing factors such as age and sex, and oral health status and periodontal symptoms were related to not using the dental scaling. Therefore, the universality of health care services should be considered so that people who need periodontal care can use scaling.