• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회
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• pp.1103-1109
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• 2010

In this paper in order to analyze the mechanical properties, the permeability and the freezing properties of SB-2 materials which are mainly used with the subbase materials on the rod. For this ends, a series of the physical test, the permeability test and the freezing test were carried out the samples mixed the small aggregate and the big aggregate from which was re-classified the SB-2. From the test results, it was analyzed the characteristics of permeability and the characteristics of freezing of the samples.

• 한국해양공학회지
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• 제28권6호
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• pp.493-499
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• 2014

The resistance performances were studied for two 50-ft-class power yachts made of carbon fiber reinforced plastic (CFRP) with different hull form characteristics using model tests. The tests were carried out at a high-speed circulating water channel (CWC) for the 16–38 knot range. The total resistance, trim, and sinkage were measured, and the results were compared with wave patterns. The results showed that a chine position at the draft line had a strong effect on the planning performance and resistance performance in a certain velocity range.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 지반공학 공동 학술발표회
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• pp.231-238
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• 2005

Incompetent sediments and competent volcanics are consisted of the Cenozoic geology in Korea. Although the Cenozoic area is small, it is necessary to special interesting for ground of these geological material. The Cenozoic geology shows heterogeneous characteristics. We can look at the weak Cenozoic sedimentary rocks under the hard Cenozoic basalt in the area. Some Cenozoic un(or half)-consolidated soft sediments have large, heavy and hard boulders. Some volcanics and tuffaceous sediments have swelling clays. These characteristics give very difficult problems to engineering geologists and civil engineers.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 B
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• pp.924-926
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• 2001

This paper presents the characteristics of current harmonics and torque ripple of Brushless DC motor, which is developed the fan blower of vehicles, according to permanent magnet shape input voltage wave form. To investigate the torque ripple and the phase current harmonics, these characteristics is analysed and compared the experimental results. In the process of analysis, FEM is introduced and computed a transient state torque of BLDC with a sinusoidal and a PWM wave voltage.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 B
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• pp.849-851
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• 2001

This paper presents experimental method of parameter measurement and starting characteristics of 3 phase induction motor. Equivalent circuit parameters measured by DC test, the blocked rotor test, and no load test were used as the input data for computer simulation. Starting characteristics, such as starting current and torque were analyzed through computer simulation by Matlab, and the simulation results were compared with experiment using strain gauge attached on motor shaft. We conform that experimental results are very similar to that of simulation.

• Journal of information and communication convergence engineering
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• 제5권4호
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• pp.320-323
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• 2007

This paper presents the resonance characteristics of the ZnO-based FBAR devices with multilayered Bragg reflectors with Cr adhesion layer inserted between $SiO_2$ and W layers. Due to the post- annealing, the return loss ($S_{11}$) and series/parallel quality factor are significantly improved when compared with the non-post annealing. This post-annealing method seems to be a very efficient way to improve the resonance characteristics of FBAR devices.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2004년도 춘계학술발표회
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• pp.327-333
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• 2004

Corestone ground mass has complicated characteristics as it is made up of hard and stiff corestone in a relatively weak and soft matrix. Model corestone ground mass which is physically identical with the stiff corestone in weak matrix were tested in uniaxial compression. The tests show that the increase of the corestone proportion brought the gradual increase of the elastic modulus as well. The ground mass was weaker when the corestone proportion was low while it was stronger in higher corestone proportion. The size of the corestone had no influence on the strength and elastic modulus as long as the proportion of the corestone remains same.

• 한국세라믹학회지
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• 제53권2호
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• pp.167-170
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• 2016

Various piezoelectric nanostructures have been extensively studied for competitive energy harvesting applications. Here, GaN nanowires grown by a nonconventional magnetic field-assisted chemical vapor deposition process were investigated to characterize the piezoelectric energy harvesting characteristics. As a controlling parameter, only the growth time was changed from 15 min to 90 min to obtain different crystallinity and morphology of the nanowires. Energy harvesting characteristics were found to depend largely on the growth time. A longer growth time tended to lead to an increased output current, which is reasonable when considering the enhanced charge potentials and crystallinity. A maximum output current of ~14.1 nA was obtained for the 90 min-processed nanowires.

• 한국정밀공학회지
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• 제18권9호
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• pp.96-100
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• 2001

As the track density of hard disk drives increases, there is a need for more precise actuation of the head. This can be accomplished by using a high band width micro-actuator. In this work, the flying characteristics of sliders with micro-actuators are investigated with the aim to optimize the head/disk interface performance of such sliders. Contact-start-stop, sweep, and flying height tests are performed and analyzed. The results show that the MEMS based micro-actuator mounted on a slider possess acceptable flying characteristics.

• Advances in nano research
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• 제1권1호
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• pp.13-27
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• 2013

Carbon nanotube characterized by additional inductive effect as compared with the traditional conductors like copper wires of the same size. Consequently, carbon nanotubes have high characteristic impedance and slow wave propagation in comparison with traditional conductors. Due to these characteristics, carbon nanotubes can be used as antenna. In view of this, we describe and review the present research progress on carbon nanotube antennas. We present different analysis models and results which are developed to investigate the characteristics of CNT antennas. Then we conclude by summarizing the characteristics of CNT antennas and specifying the operating frequency limit.