• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.794-799
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• 2005

Robust DC-DC converter which can cover extensive load changes and also input voltage changes with one controller is needed. In this paper, we propose a method for determining the parameters of 2DOF digital controller which makes the control bandwidth wider, and at the same time makes a variation of the output voltage very small at sudden changes of resistive load and the input voltage. The 2DOF digital controller whose parameters are determined by the proposed method is actually implemented on a DSP and is connected to a DC-DC converter. Experimental studies demonstrate that this type of digital controller can satisfy given specifications.

• Korean Journal of Ichthyology
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• v.21 no.sup1
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• pp.63-72
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• 2009

The taxonomic research based on extensive investigations and specimen collections throughout all varieties of freshwater and marine habitats of Chinese waters, including mainland China, Hong Kong and Taiwan, which involved accounting the vast number of collected specimens, data and literature (both within and outside China) were carried out over the last 40 years. There are totally 361 recorded species of gobioid fishes belonging to 113 genera, 5 subfamilies, and 9 families. This gobioid fauna of China comprises 16.2% of 2211 known living gobioid species of the world. This report represents a summary of previous researches on the suborder Gobioidei. A recently diagnosed subfamily, Polyspondylogobiinae, were assigned from the type genus and type species: Polyspondylogobius sinensis Kimura & Wu, 1994 which collected around the Pearl River Delta with high extremity of vertebral count up to 52-54. The undated comprehensive checklist of gobioid fishes in China will be provided in this paper.

• Structural Engineering and Mechanics
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• v.9 no.2
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• pp.195-208
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• 2000

To confirm the theory and static defect energy (SDE) equations proposed in the first part, extensive numerical simulation studies are performed in this portion. Stiffness method is applied to calculate the components of the stresses and strains from which the energy components and finally, the SDE are obtained. Examples are designed to cover almost all kinds of possibilities. Variables include structural type, material, cross-section, support constraint, loading type, magnitude and position. The SDE diagram is unique in the way of presenting damage information: two different energy constants are separated by a sharp vertical drop right at the damage location. Simulation results are successfully implemented for both methods in all the cases.

• Proceedings of the KIPE Conference
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• 2003.11a
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• pp.226-229
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• 2003

Increasing of the use nonlinear power electronics equipments, power conditioning systems have been researched and developed for many years to compensate the harmonic disturbances and the reactive power. The main function of power conditioning systems is to reduce harmonic distortions, since extensive surveys quantify the problems associated with electric networks having non-linear loads. The main function of power conditioner compensates the current instead of the voltage. Therefore the inverter used in power conditioner is mostly current controlled type. In this paper, the proposed current control algorithm is analysed and discussed about how to design the controller which can apply power conditioning operation for grid-connective PV power system. And also proposed control system. To verify the proposed current control algorithm, a comprehensive evaluation with theoretical analysis, simulation, experiment results is presented.

• Journal of the Korean Operations Research and Management Science Society
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• v.30 no.1
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• pp.27-41
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• 2005

This paper considers identical parallel machine scheduling problem. Each job has a processing time. due date. weight and family type. If a different type of job is followed by prior job. a family setup is incurred. A two phased heuristic is presented for minimizing the sum of weighted tardiness. In the first phase. using roiling horizon technique. group each job into same family and schedule each family. In the second phase. assign each job to machines using schedule obtained in the first phase. Extensive computational experiments and comparisons among other algorithms are carried out to show the efficiency of the proposed algorithm.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.26 no.2
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• pp.199-204
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• 2017

In this study, analytical methods for designing a torque arm pin and elastomeric bushings of a conventional-type three-point-suspension gearbox of a wind turbine are investigated. The design loads for the torque arm were derived by considering the effects of the transmitted torque and self-weight of the gearbox. Based on the design loads, design methods for the torque arm pin and elastomeric bushings were introduced in the terms of material and size selection. Finally, a small-scale conventional-type gearbox was designed by applying the derived design methods. This study is an elementary and analytical study for the design of the torque arm pin and elastomeric bushings. It is necessary to verify and supplement the results further through extensive experimentation.

• Animal Systematics, Evolution and Diversity
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• no.nspc3
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• pp.93-100
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• 1992

Seven geographical variation types of G.sobaegensis in South Korea were reported by Kim and Lee(1977) and Lee and Kim (1980). After extensive reexamination, we considered type 4, one of the variation types collectd from various localities of Kyongsangbuk-do Pongwha-gun, as a new species This new species is named as Gammarus longisaeta and fully described and illustrated. Adding this new species, total 9 species of freshwater Gammarus are Known to Korea.

• International Journal of Aeronautical and Space Sciences
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• v.6 no.2
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• pp.33-45
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• 2005

The 1/9-scale model of a fighter-type configuration was tested in the Micro-Craft 8ft ${\times}$ 12ft wind tunnel facility. An abrupt lift dump was found at a certain range of angle of attack under the pre-scheduled approach configuration. To avoid a probable unsatisfactory flight behavior due to the lift dump, various aerodynamic devices were suggested. Extensive tests applying the cutoff leading edge flaps, boundary layer fences, saw tooth and vortex generators were performed with flow visualization as well as force and moment measurements. Test results showed that the origin of the lift dump was caused by the secondary boundary layer flow separation generated from the strong interaction between wing and flap. Various solutions for avoiding the unfavorable feature were suggested with the merits and demerits.

• Journal of Applied Biological Chemistry
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• v.49 no.2
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• pp.48-50
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• 2006

Four ursane-type triterpenoids, ursolic acid (1), 23-hydroxyursolic acid (2), corosolic acid (3), and tormentic acid (4), and a phytosterol, ${\beta}-sitosterol-3-O-{\beta}-D-glucoside$, were isolated from an EtOAcsoluble extract of the aerial parts of Potentilla discolor. The structures of 1-4 were identified by spectroscopic methods, particularly by extensive NMR studies. This is the first report on the isolation of compounds 1-4 from this plant.

• Journal of the Korea Society for Simulation
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• v.6 no.1
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• pp.85-96
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• 1997

Designing and constructing a proper simulator for real power plants requires extensive research in human engineering and computer science and integration of different fields of technologies such as system analysis, operational knowledge for nuclear plant, etc. A full scope replica type simulator for nuclear power plant is developed. The simulator has the same feature and operational functions as one in the main control room (MCR) of a reference power plant. The simulator provides the necessary training to recover or reduce damages from accidents that usually are unpredictable. This paper describes the configurations and characteristics for the simulator that is developed for Younggwang Nuclear Power Plant #3,4 which is the basic model of the Korean Nuclear Power Plant. The paper also describes technical aspects of Auto Code Generator that is used for developing the simulator. The successful development of the simulator will contribute to improve safety in operation of nuclear power plants.