• KSTLE International Journal
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• 제1권1호
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• pp.59-62
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• 2000

This paper deals with an experimental study on the dynamic response of an elastomeric oil seal when the interferences between shaft and lip as well as the dynamic eccentricities are present. The dynamic response of seal lip in oil seals was observed with the aid of an image processing apparatus. The temperature of the seal lip edge, friction torque and the dynamic sealing gap between shaft and lip are measured at different conditions of the initial interference and the shaft eccentricity, The data were simultaneously measured under dynamic conditions. Experimental results show that, as the shaft speed is increased, S/e$_{d}$ has nearly reached a constant asymptotic value fur a certain range of shaft speeds. The results indicate that the gap separation between shaft and lip is provided due to the shaft eccentricity because the seal lip cannot follow quickly the radial displacements with increasing shaft speed.d.

• Food Science and Biotechnology
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• 제14권1호
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• pp.28-31
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• 2005

To extract apple pectins, apple pomace (AP) was extruded under 14 different conditions of screw speed (250-350 rpm), feed rate of 30-40 kg/hr, and 20-30% moisture content using twin-screw extrusion. Response surface methodology (RSM), based on three variables by three-level factorial design, was employed to investigate effects of screw speed, feed rate, and moisture on dependent variables of extrudates, soluble dietary fiber (SDF), yield of anhydrogalacturonic acid ($Y_{AGA}$) representing pectin, and intrinsic viscosity ([${\eta}$]). Second order models were used to generate three-dimensional response surface for dependent variables, and their coefficients of determination ($R^2$) ranged from 0.96 to 0.99. Moisture content showed highest effect on solubilization of AP.

• Journal of Electrical Engineering and Technology
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• 제1권4호
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• pp.466-471
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• 2006

This raper presents a new optimization method combining the genetic algorithm with the response surface method for the optimum design of a Brushless Direct Current motor. The method utilizes a regression function approximating an objective function and the window moving and zoom-in method so as to complement disadvantages of both the genetic algorithm and response surface method. The results verify that the proposed method is powerful and effective in reducing cogging torque by optimizing only a few decisive design factors compared with the conventional stochastic methods.

• Journal of Information Technology Services
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• 제2권2호
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• pp.87-95
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• 2003

With the increasing proliferation of World Wide Web, electronic mail systems have become very widely used communication tools. Researches on e-mail classification have been very important in that e-mail classification system is a major engine for e-mail response management systems which mine unstructured e-mail messages and automatically categorize them. in this research we develop e-mail classifiers for e-mail Response Management Systems (ERMS) using naive bayesian learning and centroid-based classification. We analyze which method performs better under which conditions, comparing classification accuracies which may depend on the structure, the size of training data set and number of classes, using the different data set of an on-line shopping mall and a credit card company. The developed e-mail classifiers have been successfully implemented in practice. The experimental results show that naive bayesian learning performs better, while centroid-based classification is more robust in terms of classification accuracy.

• JSTS:Journal of Semiconductor Technology and Science
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• 제14권6호
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• pp.810-817
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• 2014

An on-chip current sensor with fast response time for the peak-current-mode buck regulator is proposed. The initial operating points of the peak current sensor are determined in advance by the valley current level, which is sensed by a valley current sensor. As a result, the proposed current sensor achieves a fast response time of less than 20 ns, and a sensing accuracy of over 90%. Applying the proposed current sensor, the peak-current-mode buck regulator for the mobile application is realized with an operating frequency of 2 MHz, an output voltage of 0.8 V, a maximum load current of 500 mA, and a peak efficiency of over 83%.

• The Journal of Society for e-Business Studies
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• 제3권1호
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• pp.175-194
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• 1998

The purpose of this study is to examine the current status of Quick Response adoption, and to recognize the implementation problems of QR system in the Korean fashion industry. We reviewed the theoretical background of QR system, analyzed the current status of QR adoption, and identified critical issues to implement the system in our fashion business environment. Previous literatures and information gained from communication service organizations were used for this study The major problems recognized are lack of inter-organizational information network, closed supply channels, non-standardization of QR implementation, and low level of information technology usage including KAN, POS, and EDI. Strong mutual partnership between streams for shared common goals and clear QR mind setting of top management with commitment to information sharing are considered needed for the successful adoption of QR system in domestic fashion industry.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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• pp.825-828
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• 2007

This paper presents a thermally adaptive driving (TAD) technology for response time compensation of LCD with integrated sensor. The TAD is comprised of analog sensor signal conditioning and a digital feedback algorithm. Utilizing with a digital feedback system, TAD reduces response time of nearly 50% over the temperature range $0^{\circ}C-60^{\circ}C$.

• Structural Engineering and Mechanics
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• 제12권3호
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• pp.341-346
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• 2001

Near source earthquakes can be characterized not only by strong horizontal but also by strong vertical ground motions with broad range of dominant frequencies. The inelastic horizontal response of thin-walled L-shaped steel bridge piers, which are popularly used as highway bridge supports, subjected to simultaneous horizontal and vertical ground excitations of near source earthquakes is investigated. A comprehensive damage index and an evolutionary-degrading hysteretic model are applied. Numerical analysis reveals that the strong vertical excitation of a near source earthquake exerts considerable influences on the damage development and horizontal response of thin-walled L-shaped steel bridge piers.

• Structural Engineering and Mechanics
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• 제53권2호
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• pp.249-260
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• 2015

Damage detection based on a reference set of measured data usually has the problem of different environmental temperature in the two sets of measurements, and the effect of temperature difference is usually ignored in the subsequent model updating. This paper attempts to identify the structural damage including the temperature difference with artificial measurement noise. Both local damages and the temperature difference are identified in a gradient-based model updating method based on dynamic response sensitivity. The sensitivities of dynamic response with respect to the system parameters and temperature difference are calculated by direct integration method. The measured dynamic responses of the structure from two different states are used directly to identify the structural local damages and the temperature difference. A single degree-of-freedom mass-spring system and a planar truss structure are studied to illustrate the effectiveness of the proposed method.

• Smart Structures and Systems
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• 제25권6호
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• pp.679-691
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• 2020

To identify the bridge information from the response of test vehicles passing on it (also known as the indirect approach) has aroused the interest of many researchers thanks to its economy, easy implementation and less disruption to traffic. The surface roughness of bridge remains an obstacle for such method as it contaminates the vehicle response severely and thereby renders many vehicle-response-based bridge identification methods ineffective. This study aims to eliminate such effect with the responses of two different test vehicles. The proposed method can estimate the surface profile of a bridge based on the acceleration data of the vehicles running on the bridge successively, and obtain the normalized contact point response, which proves to be relatively immune to surface roughness. The frequencies and mode shapes of bridge can be further extracted from the normalized contact point acceleration with spectral analysis and Hilbert transform. The effectiveness of the proposed method is verified numerically with a three-span continuous bridge. The influence of measurement noise is also examined.