• Proceedings of the KIEE Conference
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• 1993.07b
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• pp.742-745
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• 1993

In this paper, instantaneous current tracking control inverter is applied to photovoltaic system and then optimum operating area is described by state space average method for optimum design of maximum output control. Also control system is realized by DSP and excellence of system shows the effectiveness of inverter system using the instantaneous control method.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1992.12a
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• pp.19-20
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• 1992

salad, desert용으로 수요가 급속히 증가하고 있는 방울토마토를 대상으로, 국내품종과 우리나라에서 지배되고 있는 일본품종중 수경재배방식에 적합한 방울토마토 품종을 선발하고, 또한 우리나라에 적합한 수경재배방식을 개발하는 것을 실험목적으로 한다. (중략)

• 제어로봇시스템학회:학술대회논문집
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• 1989.10a
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• pp.109-112
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• 1989

Gun system operation is represented as a first-order Markov process, and an optimum linear filter is derived for closed-loop control of mean square error. Potential improvement is then estimated by contrasting the variance in performance and the auto correlation for open-loop system with that for the optimum linearly corrected process.

• Journal of Korean Association for Spatial Structures
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• v.1 no.2 s.2
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• pp.59-66
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• 2001

This paper describes three modules for development of the Space Frame Integrated Design System(SFIDS). The Control Module is implemented to control the developed system. The Model Generation Module based on PATRAN user interface enables users to generate a complicated finite element model for space frame structures. The Optimum Design Module base on a branch of combinatorial optimization techniques which can realize the optimization of a structure having a large number of members designs optimum members of a space frame after evaluating analysis results. The Control Module and the Model Generation Module Is implemented by PATRAN Command Language(PCL) while C++ language is used in the Optimum Design Module. The core of the system is PATRAN database, in which the Model Generation Module creates information of a finite element model. Then, PATRAN creates Input files needed for the analysis program from the information of the finite element model in the database, and in turn, imports output results of analysis program to the database. Finally, the Optimum Design Module processes member grouping of a space frame based on the output results, and performs optimal member selection of a space frame. This process is repeated until the desired optimum structural members are obtained.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.21 no.8
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• pp.1298-1310
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• 1997

In recent years, grinding techniques for precision machining of brittle materials used in electric, optical and magnetic parts have been improved by using superabrasive wheel and precision grinding machine. The completion of optimum dressing of superabrasive wheel makes possible the effective precision grinding of brittle materials. However, the present dressing system cannot have control of optimum dressing of the superabrasive wheel. In this study, a new system and the grinding mechanism of optimum in-process electrolytic dressing were proposed. This system can carry out optimum in-process dressing of superabrasive wheel, and give very effective control according to unstable current and gap increase. Therefore, the optimum in-process electrolytic dressing is a good method to obtain the efficiency and mirror-like grinding of brittle materials.

• Journal of computational fluids engineering
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• v.2 no.1
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• pp.66-72
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• 1997

Optimum nozzle design exploiting the method of characteristic(M.O.C) has been in application as an efficient design methodology targeting a less weighted and short expansion nozzle. This paper treats the optimum nozzle design and the analysis of the inviscid compressible flow inside. Based on traditional Rao's method, the optimum nozzle design is coded with minor modifications for the identification of the control surface across which the mass flux should be conserved. Internal flow field is simulated numerically by M.O.C and implicit/explicit Taylor-Galerkin finite element method(F.E.M) with the aid of adaptive remeshing to capture the shock wave, hence improve the accuracy. Designed and calculated flow fields due to the separate analyses show that the mass flux predicted by optimum nozzle design with M.O.C is not conserved across the control surface and the sonic line should be located upstream of the nozzle throat. Rao's optimum nozzle design methodology exaggerates the momentum thrust and tends to overemphasize the engine performance loss.

• Journal of Institute of Control, Robotics and Systems
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• v.10 no.2
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• pp.164-170
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• 2004

Recently, the demand for micro hard disk drive that provides high-capacity removable storage for handhold electronic devices is growing very rapidly Reducing power consumption is one of the primary control objectives in micro disk drives. The input power delivered to the seek servo system is consumed as heat by the transistors of power amplifier and motor coil resistance. In this paper, we present a new seek servo controller for minimizing the power consumption. We use a Fourier decomposition and nonlinear programming to determine the optimum seek profile that minimizes the power consumption. Also, the trajectory tracking controller is developed for exact tracking of the optimum seek profile. Finally, we present some experimental results using a commercially available micro disk drive in order to demonstrate the superior performance of the proposed controller.

• Wind and Structures
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• v.35 no.2
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• pp.121-130
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• 2022

In this paper, the issue of pitch control in a vertical axis wind turbine was tackled. Programming the Actuator Cylinder model in MATLAB, a theoretical optimum pitch solution was found and then a classic four-bar mechanism was adapted to that theoretical solution to achieve a simple and elegant control of the pitch in the turbine. A simulation using the mechanism worked to find the optimum pitch cycles, where it was found that the mechanism would, in fact, increase the efficiency of the VAWT, by at least 11% and in the best case, over 35%. Another aspect that is studied is the possibility of self-start of the turbine by only changing the pitch on the blades. This analysis, however, proved that a further individual pitch control must be used to surpass the cogging torque. All analyses conducted were done for a specific wind turbine that is 2 m² in the swept area.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.94.1-94
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• 2003

Control of bacterial blossom blight of kiwifruit (Actinidia deliciosa) has been mainly depended on chemical control. Recently cultural practices such as trunk girdling of kiwifruit trees and rainproof installation over kiwifruit trees also were conducted as the alternative control practices. Each of the control methods was evaluated for the best practicing conditions for the control of bacterial blossom blight of kiwifruit. Among the various combinations of spray times and spray periods, optimum spray program of antibiotics was turned out to be 3 times with intervals of 10 days from early May during the flowering season of kiwifruits. Optimum periods of trunk girdling of kiwifruit trees were from late March to late April. Trunk girdling with 20-30 mm wide showed best control efficacies on bacterial blossom blight, irrespective of the heights of girdling on trunks of kiwifruit trees. Optimum period of rainproof installation over kiwifruit trees was from March till late April, irrespective of installation methods.

• Plant Disease and Agriculture
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• v.5 no.2
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• pp.95-99
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• 1999

Chemical control of bacterial canker of kiwifruit caused by Pseudomonas syringae pv. actinidiae was attempted by spraying of streptomycin sulfate ·oxytetracycline WP streptomycin WP streptomycin ·copper hydroxide WP kasugamycin SL kasugamycin·copper oxychloride WP and copper hydroxide WP. The control efficacies of the bactericides were variable depending upon the spraying schedule,. Application of streptomycin WP and streptomycin sulfate·oxytetracycline WP from middle April to early May was found to be the most effective in controlling the bacterial canker. For copper hydroxide WP the spraying from middle January to early February showed the highest control efficacy. Kasugamycin SL was the most effective in controlling the disease by spraying from middle April to early May but it was still relatibvely effective during other spray periods. Foliar application of copper hydroxide WP and copper-antibiotic formulaions after middle April caused severe phytotoxicity. Kasgamycil SL streptomycin WP streptomycin·copper hydroxide WP and copper hydroxide WP were potential bactericides which could substitute streptomycin sulfate·oxytetracycline WP. Selective applications of the bactericides according to their optimum spray time can enhance the control efficacies against bacterial canker of kiwifruit and retard the emergency of resistant strains of P. syringae pv. actinidiae to the bactericides. The optimum spray number of streptomycin sulfate·oxytetracycline WP was 3 times with 15-day-intervals or 4 times with 10-day-intervals. The result suggested that the potential bactericides to bacterial canker of kiwifruit should be also used according to their optimum spray schedules in order to get their highest control efficacies.