• 전기의세계
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• v.29 no.8
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• pp.519-523
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• 1980

The traditional mechanical manometer is improved to develop more convenient and precise manometer in continuous measurement of the gas pressure in medium-low vacuum range (1x10$^{-1}$ -10 Torr.) Glass (solid) is used as a detector material of the improved manometer. Using the strain gauge adhered to thin glass board, mechanical strain corresponding to variation of pressure in measurement system is converted into quantity of electricity, and the quantity of electricity is amplified. Experiments have also shown that the improved manometer have more advantages in reproducibility, measured sensibility, and responsible velocity than taditional one.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1998.10a
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• pp.25-29
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• 1998

Sliding wear test and surface characterization techniques such as micro-Raman spectroscopy were employed to determine the effect of whisker content and orientation on the friction and wear behavior of SiC whisker reinforced alumina. Composites containing unidirectionally oriented whiskers were fabricated by novel technique Addition of SiC whiskers up to 20 vol.% lowered the friction and improved wear resistance. The results of this study indicated that highly disordered graphite and size of the layer behind the whiskers were responsible for variation of wear rate and friction coefficient.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.28A no.5
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• pp.398-406
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• 1991

This paper presents a graphics accelerator for fast image generation. The accelarator has three major functional blocks: linear interpolator, multipliers and Edgee Painting Tree. Linear interpolator with coupled binary tree structure interpolates functional values of two end points. Two multipliers compute input values of interpolator in parallel. Mask pattern which removes out invalid data is generated by Edge Painting Tree. The proposed architecture in this paper is responsible for 64 pixels and can process about 5,900 10x10polygons per second.

• Journal of Technology Innovation
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• v.13 no.1
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• pp.169-191
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• 2005

By analyzing a national survey of public understanding of science and technology, this paper attempts to examine public perceptions of scientists and engineers in Korea. A special attention is given to the gap in the view of scientists and engineers across generation, gender, and class fields (or major fields). This paper shows that generation has the strongest effect on public perceptions of scientists and engineers among all the socio-demographic factors examined in this study. Those over 50 are more likely to have the conventional idealized images of scientists and the stereotypical negative images of scientists simultaneously, while the 20s are less likely to accept the idealized image of scientists. The survey result thus may suggest that the younger generation began to depart from a patriotic and moral description of scientists and engineers-for the younger generation, science and engineering is losing moral respect but becomes perceived as an ordinary occupation. Contrary to the popular belief, however, gender has little effect on public perceptions of scientists and engineers. This finding questions the assertion that female students possess more negative attitudes toward scientists and engineers than male students, and thus are reluctant to develop careers related to science and engineering. By uncovering that class fields (or major areas) have no effect on the image of scientists, this study also call into question the assertion in the science wars that the inadequate appreciation of science particularly among those who do not major in science and engineering is responsible for inadequate support for science and technology.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.21 no.1
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• pp.63-78
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• 2009

This paper presents the development of dynamically combined Typhoon generated surge-tide-wave numerical model which is applicable to shallow water. The newly developed model is based on both POM (Princeton Ocean Model) for the surge and tide and WAM (WAve Model) for wind-generated waves, but is modified to be applicable to shallow water. In this paper which is the first paper of the two in a sequence, we verified the accuracy and numerical stability of the hydrodynamic part of the model which is responsible for the simulation of Typhoon generated surge and tide. In order to improve the accuracy and numerical stability of the combined model, we modified algorithms responsible for turbulent modeling as well as vertical velocity computation routine of POM. Verification of the model performance had been conducted by comparing numerical simulation results with analytic solutions as well as data obtained from field measurement. The modified POM is shown to be more accurate and numerically stable compare to the existing POM.

• Journal of the Korean Society of Propulsion Engineers
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• v.22 no.1
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• pp.45-51
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• 2018

The generation mechanism of NAR is not yet understood. In the present study, an in-depth analysis of the computational results previously obtained by the authors is conducted to investigate the flow mechanism responsible for NAR. A theoretical analysis has also been performed to understand the gas dynamic features during transition from scramjet to ramjet mode. It is known that there exists a critical value of the fuel equivalence ratio at which the flow states at the inlet of isolator remain unchanged. An increase in the equivalence ratio over the critical value leads to a sudden change in the static pressure and the Mach number at the inlet of the isolator, which is responsible for the generation of NAR.

• Communications of the Korean Institute of Information Scientists and Engineers
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• v.4 no.2
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• pp.74-80
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• 1986

Budgeting system is a managerial planning which is the object and the standard of managerial activity. But we often see a budgeting svstem which is nonscientifie and nonpractical at present in Korea. So the object of this paper is that we try to estimate of which responsible management is executed. The technique of budget planning is a simulation based on computer processing. In simulation technique we seek a relative optimal amount that affects an object profit.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.27 no.7
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• pp.443-447
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• 2014

ZnO crystals with different morphologies were synthesized through a thermal evaporation of Zn-Mn mixtures in air. The morphology was dependant on the Mn content in Zn-Mn mixture. The morphology was changed from rod to tetrapod shape with decreasing Mn content in Zn-Mn mixture. The result indicates that the concentration of Mn might be responsible for the different morphologies of ZnO crystals. XRD spectra showed that the ZnO crystals had a hexagonal wurtzite crystal strutures. For all the samples, room temperature cathodoluminescence spectra showed a ultra-violet emission at 380 nm and a green emission at around 500 nm. However, the intensity ratio of ultra-violet emission to green emission was significantly different with the Mn content in the source material.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2002.11a
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• pp.151-156
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• 2002

The output voltage of Synchronous Generator is regulated constantly by field current control in excitation system. A synchronous generator is equipped with an automatic voltage regulator(AVR), which is responsible for keeping the constant output voltage under normal operating conditions about various levels. High frequency PWM converter (Current Mode Control Buck converter) type excitation system for synchronous generator is able to sustain output voltage level properly when the fault condition happened. This paper deals with the design and evaluation of the excitation system controller for a synchronous generator to improve the steady state and transient stability. The simulation and experimental results show that the proposed excitation system is improve the respons time by the AVR(automatic voltage regulator) of 50kW synchronous generator that is applied the current mode control excitation system.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.10
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• pp.1720-1725
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• 2008

Because of the continuous increasing of energy consumption, metallic pipelines are widely used to supply services to customers such as gas, oil, water, etc. Most common metallic pipelines are underground and are now frequently being installed in nearby electric power lines. In recent years, buried gas pipeline close to power lines can be subjected to hazardous induction effects, especially during single line to ground faults. because it can cause corrosion and it poses a threat to the safety of workers responsible for maintenance. Accordingly, it is necessary to take into consideration for analysis of induced voltage on gas pipelines in transmission lines. This paper analyzed the induced voltage on the gas pipelines due to the 154kV transmission lines in normal case and in different faulty case conditions using EMTP (Electro-Magnetic Transients Program).