• The Transactions of the Korean Institute of Power Electronics
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• v.6 no.1
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• pp.13-20
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• 2001

In this appear, we proposed the new current mirror has large output resistance and excellent current matching characteristics. If supply voltage were lowered under the conventional CMOS operational amplifier, the wing of out put power could be restricted. So, the paper suggests a new way of differential operational amplifier circuit to solve the problem. The paper proposes that a new current mirror increases output swing and has a stable operation. We compare and verify characteristics of the proposed current mirror with the cascoded current mirror and the regulated current mirror through simulation.

• Journal of Industrial Technology
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• v.11
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• pp.43-53
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• 1991

Two kinds of simple active oscillators are proposed and analyzed assuming that operational amplifier has two-poles frequency characteristics. The first circuit is composed of one operational amplifier, one resistor and one grounded capacitor. The second oscillator is realized with one operational amplifier and three resitors. Proposed oscillators have the low sensitivity of the oscillation frequency for little variations of the passive element values. By the experimental results obtained with Op-Amp. ${\mu}A741$, the simple oscillators can be useful for the frequency range $1.25 KHz{\leq}f_{01}{\leq}40KHz$ for the active-RC type or $45.45 KHz{\leq}f_{02}{\leq}400KHz$ for the active-R oscillator, and it is shown to transform the active-R oscillator circuit into the voltage controlled type. Therefore, two kinds of oscillator circuit are attractive for the IC realization, because they have one operational amplifier, one resistor and one grounded capacitor, or three resistors.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.6
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• pp.110-117
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• 2003

The operational characteristics of the landing gear retraction/extension depend on the complexity of design variables operational/environmental conditions. In order to meet the requirements of minimum stow area and performance, the integration of the landing gear system requires operational kinematic and dynamic analysis considering an effect of its related system. This study investigates operational dynamic behaviors of the T-50 landing gear system using ADAMS. Taking into account for various operational/environmental conditions, an analysis of dynamic behavior on the landing gear operational characteristics is performed with experience derived from a wide range of proprietary designs. Analytical results are presented for discussing the effects of temperature, aerodynamic and maneuver load on normal/emergency operation of the landing gears and doors. This analysis leads us to the conclusion that the proposed program is shown to be a better quantitative one that apply to a new development and troubleshooting of the landing gear system.

• The Journal of Asian Finance, Economics and Business
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• v.6 no.3
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• pp.55-65
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• 2019

The purpose of this study is to discover the interaction between credit growth and operational self-sustainability and to examine factors that affect credit growth and operational self-sustainability of people's credit funds (PCFs). Credit growth and operational self-sustainability are factors affecting the operations and the goals of people's credit funds (PCFs) in the Mekong Delta region of Vietnam. After regression analysis on a set of panel data from 2013 to 2018 of 24 PCFs, it appears that deposit growth and loan-to-deposit ratio have positive relationships with credit growth, while capital adequacy ratio and operational self-sustainability have negative relationships with credit growth of PCFs; capital adequacy ratio, deposit growth and income have positive relationships with operational self-sustainability, while credit growth and non-performing loan ratio have negative relationships with the operational self-sustainability of PCFs. At the same time, credit growth and operational self-sustainability have a relationship to interact with each other in a contrary trend. The results of this research are accurate according to the characteristics and development history of PCFs in the Mekong Delta region of Vietnam from 2013-2018. This study helps researchers and managers to understand the key determinants for better management of PCFs.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.1425-1429
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• 2007

Consumer's product selection measures are being shifted from the units' operational performance to overall performance. Low noise, low vibration, and low power consumption rate, etc. which used to be additional quality indices, now become vital performance factors. Especially, noise and vibration characteristics are being considered as equivalent to/or even more critical than operational performance in certain products such as office machines and home entertainment systems, which share the same space with human being's daily life. Therefore, noise reduction and sound quality improvement technology becomes an inevitable design issue for those applications. Qualitative noise characteristics of rotating polygonal disk applied to digital printer systems are presented. Overall sound pressure level change and tonal noise variation with respect to the geometrical properties of polygonal disk, operational speed, and others are briefly discussed based on experimental results.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.18 no.6
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• pp.606-611
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• 2008

Consumer's product selection measures are being shifted from the units' operational performance to overall performance. Low noise, low vibration, and low power consumption rate, etc. which used to be additional quality indices, now become vital performance factors. Especially, noise and vibration characteristics are being considered as equivalent to/or even more critical than operational performance in certain products such as office machines and home entertainment systems, which share the same space with human being's daily life. Therefore, noise reduction and sound quality improvement technology becomes an inevitable design issue for those applications. Qualitative noise characteristics of rotating polygonal disk applied to digital printer systems are presented. Overall sound pressure level change and tonal noise variation with respect to the geometrical properties of polygonal disk, operational speed, and others are briefly discussed based on experimental results.

• Journal of the Korean Institute of Telematics and Electronics
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• v.13 no.3
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• pp.7-10
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• 1976

To eliminate some difficulties encountered in the operation of $LiNbO_3$ crystal as a Q-switch for generating a single pulse Nd-YAG laser, the operational characteristics of the crystal, was investigated. Also a simple method for solving the difficulties was presented.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.78-78
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• 2000

This paper provides a guideline for specifying the operational compliance characteristics considering the location of compliance center and the grasp points in assembly tasks using robot hands, To be specific, some of coupling stiffness elements cannot be planned arbitrary. Through T-type assembly task, we analyze the conditions of the achievable operational stiffness matrix with respect to the location of compliance center and the grasp points. It is concluded that the location of compliance center on the grasped object and the grasp points play important roles for successful assembly tasks and also the operational stiffness matrix should be carefully specified by considering those conditions.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.51 no.12
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• pp.704-713
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• 2002

This paper describes operational characteristics of wind turbine induction generators interconnected with distribution networks using PSCAD/EMTDC. Due to the simple and durable structure, induction generators are the most common type used in wind Power generation. Generally, induction generators are classified into two groups according to the shape of rotor, one is squirrel-cage type and the other is wound-rotor type. In this study, we simulate the start-up and the output variation of generators interconnected with distribution networks and compare the operational characteristics of squirrel -cage type and wound-rotor type induction generators located in the unfaulted distribution lines about the disturbance occurred on the associated distribution feeders emanated from the substation to which wind turbine generator is connected. In order to obtain the realistic results, we use the radial distribution network of IEEE 13-bus model.

• Structural Engineering and Mechanics
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• v.37 no.6
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• pp.593-615
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• 2011

This study determines the water length effects on the modal behavior of a prototype arch dam using Operational and Analytical Modal Analyses. Achievement of this purpose involves construction of a prototype arch dam-reservoir-foundation model under laboratory conditions. In the model, reservoir length was taken to be as much as three times the dam height. To determine the experimental dynamic characteristics of the arch dam using Operational Modal Analysis, ambient vibration tests were implemented for empty reservoir and three different reservoir water lengths. In the ambient vibration tests, the dam was vibrated by natural excitations provided from small impact effects and the response signals were measured using sensitive accelerometers. Operational Modal Analysis software process signals collected from the ambient vibration tests, and Enhanced Frequency Domain Decomposition and Stochastic Subspace Identification techniques estimated modal parameters of the dams. To validate the experimental results, 3D finite element model of the prototype arch dam was modeled by ANSYS software for empty reservoir and three different reservoir water lengths, and dynamic characteristics of each model were determined analytically. At the end of the study, experimentally and analytically identified dynamic characteristics compared to each other. Also, changes on the natural frequencies along to water length are plotted as graphs. Results suggest that reservoir water complicates the modal behavior of the arch dam significantly.