• Proceedings of the KIPE Conference
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• 2005.07a
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• pp.189-191
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• 2005

This paper proposes an implementation of a line- voltage sensorless three-phase active power filter. The line synchronization for an active power filter does not require any additional hardware. It can be properly operated under various line-voltage variation. Current compensation is done in the time domain allowing fast time response. All control functions are implemented in software using a single-chip microcontroller, thus simplifying the control circuit. It is shown via experimental results that the proposed controller gives good performance for the line-voltage sensorless active power filter.

• Journal of The Korean Astronomical Society
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• v.2 no.1
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• pp.33-39
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• 1969

The gain of internal energy of a star cluster caused by the tidal attraction of our Galaxy is examined. Expressions are derived which include the effects of a two-body orbit and internal motions of the cluster. These formulae are compared with previous results based on (i) uniform rectilinear motion and (ii) neglect of internal motions induced by cluster gravitation(i.e., impulsive approximation), and it is found that these simplifying assumptions generally introduce significant uncertainties.

• Korean Journal of Mathematics
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• v.26 no.4
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• pp.675-681
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• 2018

In the paper, by virtue of techniques in combinatorial analysis, the authors simplify three families of nonlinear ordinary differential equations in terms of the Stirling numbers of the first kind and establish a new family of nonlinear ordinary differential equations in terms of the Stirling numbers of the second kind.

• 제어로봇시스템학회:학술대회논문집
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• 1989.10a
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• pp.606-608
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• 1989

Force/torque sensors are now providing widespread practical solutions to manufacturing problems, particularly in the area of automated assembly. The current state of the industry is discussed, including the evolution of transducer and controller design, and the trend of robot manufacturers to integrate force/torque sensors into their robot systems thereby greatly improving cycle time and simplifying the application development task for the end-user. Current and future application areas are discussed as well as the benefits of force/torque sensing.

• Asian Journal of Turfgrass Science
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• v.18 no.2
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• pp.71-76
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• 2004

Solid typed organic fertilizer from cattle manure may Increase plant root growth with the residual effect on soil fertility if it was applied directly into root system. It may also increase labour efficiency by simplifying the work process of manure application to soil. This research was carried out from May to October 1999 to study the fertility prolongation effects of bar typed organic fertilizer from poultry manure by analysing plant growth model compare with those of the chemical fertilizer or powder typed manure. The results showed that the bar typed organic fertilizer increased growth rates of shoot and root system with extending the effect of its fertility by slow releasing on pepper plant. Especially, solidifying organic manure into the bar type made possible the application of cattle manure under plastic mulching. And it also has benefits on simplifying the application process of the fertilization and effect on an extending soil fertility.

• Korean Journal of Digital Imaging in Medicine
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• v.13 no.3
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• pp.127-132
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• 2011

This is to improve the complicate process of the existing CD copy flow in Department of Radiology. It is also to improve the medical service of the hospital to secure private information of patients. Survey: The patients who ask for CD copies in the Department of Radiology of this hospital(for 6 months in 2010). Time: Comparing the total amount of time of the previous and the modified CD copy flow. Using the SPSS 12.0 program for testing significance of independent two-samples t-test. Private information: Introducing the identification-system based on the medical law to supplement the security of personal information of patients. There was manifold complaints due to receipt and issuing the prescription in Admission and Discharging office and outpatient department. The time has been approximately 50% reduced from 70 mistunes to 32 mistunes due to simplifying the routes. The security of the personal information has been supplemented by let patients submit documentary evidence based on the medical law. The service in the hospital has been improved as a result of simplifying the whole process of the routes and receipt process. Therefore, the each stage of waiting time has been decreased. In addition, the personal information of the patients has been more secured.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.21 no.3
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• pp.56-62
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• 2022

The tank engine clutch flange constitutes a tank on which the engine and transmission of the tank are mounted. The engine clutch flange is fabricated using a difficult-to-cut material that exhibits high strength and hardness. It is difficult to process and requires considerable processing expertise. In addition, the engine clutch flange for the tank requires high machining precision because it is a system in which the connection is detachable. Because it requires high processing precision, the measurement of products equally important as processing. However, productivity is low owing to the significant amount of time required to measure each product using a three-dimensional coordinate measuring machine. Hence, this study is conducted to improve the productivity of the female tank engine clutch flange. Dedicated hobs and jigs are designed and manufactured to convert the existing end-mill cutting processing into hobbing cutting processing. An engine clutch for the tanks is manufactured using the manufactured dedicated hob and jig, and the shortening time is verified by measuring the processing time. In addition, a jig for inspection is designed and manufactured to measure the precision of the product. To verify the inspected product, the product precision is measured using a contact-type three-dimensional coordinate measuring machine and a surface roughness measuring instrument. The study confirmed that the productivity of the engine clutch flange product for tanks can be improved by simplifying the process, reducing the processing time, and simplifying product inspection.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.37 no.2
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• pp.9-18
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• 2014

The purpose of this research is to initiate discussion to simplify existing tools and methods for managing projects which make project management a harder job to perform and a tougher task to handle. Additionally, summarizing the definitions of "project" that have been found from reviewing the relevant literature, it deliberates on revising the duties and responsibilities of project manager and proposes performance expectancy triangle explaining a relationship among accountability, responsibility and authority - the Tri-butes. It sheds light on several factors critical to the success of projects. Finally, we propose a function indicating that customer demands or desires greatly affect project complexity.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.5 no.4
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• pp.3-7
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• 1991

This paper proposes a simplifying model for the calculation of the radiant flux and radiation energy in an RD(Radiation Dominated) arcplasma. Defects of the previous models are that the radiant flux and radition energy must be numerically solved by the three dimensional integration, and these calculations demand enormous computing time. These attribute to the global properties of radiation transfer. This paper suggests a simple calculation technique of radiation characteristics by considering the relation between the plasma states and the radiation transfer process and by the systematic tabulation of the relation.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2009.10a
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• pp.850-854
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• 2009

Approximate analysis for a building installed with a friction damper is revisited to get insight of its dynamic behavior. Energy balance equation is used to have a closed analytical form solution of dynamic magnification factor (DMF) for the building with combined viscous and friction damping. It is found out that DMF is dependent on friction force ratio and resonance frequency. Linear transfer function from input external force to output building displacement is obtained by simplifying DMF equation. Root mean square of building displacement is derived under earthquake-like random excitation. Finally, design of friction damper is proposed by processing target control ratio, damping ratio factor, and friction force in sequence.