• Asian Pacific Journal of Cancer Prevention
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• v.14 no.5
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• pp.2983-2986
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• 2013

MicroRNAs (miRNAs) are small, non-coding RNAs (18-25 nucleotides) that post-transcriptionally modulate gene expression by negatively regulating the stability or translational efficiency of their target mRNAs. In this context, the present study aimed to evaluate the in vitro effects of miR-153 inhibition in the breast carcinoma cell line MDA-MB-231. Forty-eight hours after MDA-MB-231 cells were transfected with the miR-153 inhibitor, an MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay was utilized to determine the effects of miR-153 on cell viability. Flow cytometry analysis and assessment of caspase 3/7 activity were adopted to determine whether miR-153 affects the proliferation rates and apoptosis levels of MDA-MB-231 cells. Our results showed that silencing of miR-153 significantly inhibited growth when compared to controls at 48 hours, reducing proliferation by 37.6%, and inducing apoptosis. Further studies are necessary to corroborate our findings and examine the potential use of this microRNA in future diagnostic and therapeutic interventions.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.487-488
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• 2006

Picosecond (ps) laser micro-machining has emerged as an attractive method of fabricating high-precision microstructures, especially in metals. In this paper, a metallic mold for diffraction gratings is fabricated with a mode-locked 12 Ps $Nd:YVO_4$ laser. Laser pulses with a wavelength of 355nm are irradiated on the surface of NOK 80, a mold material, to generate line patterns. In order to minimize the line width, laser power is set just above the ablation threshold of NOK 80. Results show that the spectrum from the fabricated mold is good enough for some industrial application.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.33 no.10
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• pp.789-796
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• 2009

Microdroplet deposition in a micro-groove is studied numerically. The droplet shape is determined by a level-set method which is improved by incorporating a sharp-interface modeling technique for accurately enforcing the matching conditions at the liquid-gas interface and the no-slip and contact angle conditions at an immersed solid surface. The computations are carried out to investigate the droplet behavior derived by the interfacial characteristics between the liquid-gas-solid phases. The effects of contact angle, impact velocity and groove geometry on droplet deposition in a micro-groove are quantified.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.24 no.1
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• pp.103-119
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• 2020

In this work, the hydromagnetic and thermal characteristics of natural convection flow in a vertical parallel plate micro-porous-channel with suction/injection is analytically studied in the presence of Hall current by taking the temperature jump and the velocity slip at the wall into account. The governing equations, exhibiting the physics of the flow formation are displayed and the exact analytical solutions have been obtained for momentum and energy equations under relevant boundary conditions. The impact of distinct admissible parameters such as Hartmann number, Hall current parameter, permeability parameter, suction/injection parameter, fluid wall interaction parameter, Knudsen number and wall-ambient temperature ratio on the flow formation is discussed with the aid of line graphs. In particular, as rarefaction parameter on the micro-porous-channel surfaces increases, the fluid velocity increases and the volume flow rate decreases for injection/suction.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.1
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• pp.265-270
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• 2006

Recently, inertial sensors like gyros and accelerometers have been quite miniaturized by Micro Electro-Mechanical Systems (MEMS) technology. JAXA is developing a MEM-based GPS/INS hybrid navigation system named Micro-GAIA. The navigation performance of Micro-GAIA was evaluated through off-line analysis by using flight test data. The estimation errors of the roll, pitch, and azimuth were $0.03^{\circ}$, $0.05^{\circ}$, $0.05^{\circ}$ $(1{\sigma})$, respectively. he horizontal position errors after 60-second GPS outages were reduced to 25 m CEP. The attitude errors and position errors are nearly half of ones reported previously[2]. Furthermore, using the adaptive Kalman filters, the robustness against the uncertainty of the measurement noise was improved. Comparing the innovation-based and residual-based adaptive Kalman filters, it was confirmed that the latter is robuster than the former.

• 한국전산유체공학회:학술대회논문집
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• 2009.11a
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• pp.103-108
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• 2009

The droplet impact and merging process on a flat substrate with contact angle hysteresis is numerically studied. The droplet deformation is determined by an improved level-set method employing a sharp-interface technique for the stress condition at the liquid-gas interface and the contact angle condition at the liquid-gas-solid interline. Based on the computations, the droplet impact and merging pattern is investigated to find the optimal condition in manufacturing a micro-line. The effects of dynamic contact angles and droplet spacing on droplet motion are quantified.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.465-468
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• 2001

An aerostatic stage has frictionless behavior, so it has a advantage of investigation into positioning characteristics. A one-dimensional aerostatic ceramic stage with ballscrew driven and laser scale feedback system is manufactured, aiming at investigating positioning characteristic of ultra-precision stage. We confirm, this ceramic aerostatic stage has a 10nm micro resolution, and can be reduced mean of position error by compensation of numeric control command. By means of analyzing relationship of position error and change of temperature, we build a on-line compensation algorithm of position error from the measured temperature data. So we can improve repeatability of ultra-precision stage up to 34%($0.095{\mu}$) of the normal condition.

• 한국전산유체공학회:학술대회논문집
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• 2010.05a
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• pp.548-550
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• 2010

The droplet motion on a flat substrate with contact angle hysteresis is studied by solving the equations governing the conservation of mass and momentum. The liquid- gas interface is determined by an level-set method which is based on a sharp-interface representation for accurately imposing the matching or coupling conditions at the interface. The method is modified to treat the dynamic contact angle at the liquid-gas-solid interface. The computations are performed to investigate a droplet impact and merging pattern on a flat substrate to find a optimal condition in a micro-line patterning process. The effects of dynamic contact angles on droplet motion are quantified.

• Proceedings of the KIEE Conference
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• 2000.07a
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• pp.165-168
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• 2000

This paper describes the guideline of design and tuning of practical Micro 5KVA machine's digital AVR/PSS control parameters by using the computer models and testing on-line AVR step test of laboratory simulator under the no-load or load conditions. The suggested procedures can be also applied to the large scaled machine's AVR/PSS control parameter tuning in KEPCO system.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.1293-1296
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• 2008

As Flat Panel Display become large in format, the data and gate lines turn into longer, parasitic capacitance and resistance increase, and the display signal is delayed. Three dimensional architecture of multiplexing data registration integrated circuit method is used that divides the data line into several blocks and provides the advantages of high accuracy, rapid selection, and reasonable switching speed.