• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.4
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• pp.212-215
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• 2002

Tyrosinase transcript In the blood Is known as the marker of malignant melanoma and it has been often determined by using reverse transcription-polymerase chain reaction (RT-PCA) . However, after the PCR process, the quantification of amplified CDMA by the gel electrophoresis is not reliable and time-consuming. for this reason, we tried to quantify the PCR product using a cuvette-type biosensor, where the oligonucleotide probe was immobilized on the cuvette surface and the single strand CDMA, the denatured PCH product, was then hybridized onto the immobilized probe to give a response signal. The response was Immediate and takes 15 min to obtain a stable signal. The biosensor was much more sensitive comparing to the gel electrophoresis method. The quantification of PCR product using a cuvette-type biosensor was feasible and rapid.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.20 no.4
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• pp.395-400
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• 2011

Scanning Probe Lithography is a method to localized oxidation on single crystal silicon wafer surface. This study demonstrates nanometer scale non contact lithography process on (100) silicon (p-type) wafer surface using AFM(Atomic force microscope) apparatuses and pulse controlling methods. AFM-based experimental apparatuses are connected the DC pulse generator that supplies ultra short pulses between conductive tip and single crystal silicon wafer surface maintaining constant humidity during processes. Then ultra short pulse durations are controlled according to various experimental conditions. Non contact lithography of using ultra short pulse induces electrochemical reaction between micro-scale tip and silicon wafer surface. Various growths of oxides can be created by ultra short pulse non contact lithography modification according to various pulse durations and applied constant humidity environment.

• Journal of the Optical Society of Korea
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• v.5 no.2
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• pp.60-66
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• 2001

The authors discuss a prototype stylus profilometer designed to measure large optics. It consists of a low contact force type probe system, laser reference system, interferometric distance measurement system, and horizontal driving system. The probe contacts the surface ; the height and the horizontal distances of the measurement points are measured by the interferometer. The freely propagated laser beam provides the reference line during the measurement. The developed stylus profilometry shows only $\pm$60 nm of P-V error for the 157 mm diameter spherical mirror.

• Journal of the Society of Naval Architects of Korea
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• v.60 no.5
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• pp.305-319
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• 2023

This study focuses on measuring the relative wave elevation around the KSUPRAMAX-O ship and comparing it with numerical analysis results (potential and computational fluid dynamics). The relative wave elevation is a good indicator of the pressure distribution on the ship's surface, which is affected by the ship's motion, incident waves, and distributed waves. Prior to measuring the relative wave elevation, a comparative test was conducted on resistance type, capacitance type, and ultrasonic type wave probe to measure the relative wave elevation, and it was confirmed that the resistance type wave probe was suitable for measuring the relative wave elevation. A model test was performed at low speed and design speed using resistance type wave probe and compared with the results of numerical analysis result. As for the motion response, it was confirmed that the result of experiments and the result of the numerical analysis were in good agreement. The relative wave elevation showed a similar trend between the experiment and the computational fluid dynamics, but the potential analysis result showed a difference from the experiment in design speed.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.446-446
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• 2011

One dimensional (1-D) structures of ZnO nanorods are promising elements for future optoelectronic devices. However there are still many obstacles in fabricating high-quality p-type ZnO up to now. In addition, it is limited to measure the degree of the doping concentration and carrier transport of the doped 1-D ZnO with conventional methods such as Hall measurement. Here we demonstrate the measurement of the electronic properties of p- and n-doped ZnO nanorods by the Kelvin probe force microscopy (KPFM). Vertically aligned ZnO nanorods with intrinsic n-doped, As-doped p-type, and p-n junction were grown by vapor phase epitaxy (VPE). Individual nanowires were then transferred onto Au films deposited on Si substrates. The morphology and surface potentials were measured simultaneously by the KPFM. The work function of the individual nanorods was estimated by comparing with that of gold film as a reference, and the doping concentration of each ZnO nanorods was deduced. Our KPFM results show that the average work function difference between the p-type and n-type regions of p-n junction ZnO nanorod is about ~85meV. This value is in good agreement with the difference in the work function between As-doped p- and n-type ZnO nanorods (96meV) measured with the same conditions. This value is smaller than the expected values estimated from the energy band diagram. However it is explained in terms of surface state and surface band bending.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.7 no.3
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• pp.41-46
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• 2008

Generally optical components are fabricated by grinding, lapping and polishing processes. Those processes take long time to obtain optical high surface quality. In the case of large optical components, the on-machine measurement is strongly recommended because the workpiece is fragile and difficult to set up for fabricating and measuring. This paper is concerned about a swing-arm mechanism which can be used for on-machine measurement of a surface profile with a sensing probe end-effect, and also for grinding or lapping the surface with a corresponding tool. The measuring accuracy and uncertainty using a swing arm type profilometer have been studied. The experimental results show that this method is useful specially in lapping process with the accuracy of $5{\mu}m$. Those inspection data are provided for correcting the residual figuring error in next processes.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.9
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• pp.61-70
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• 2001

This paper introduces a new digitization method with sensor fusion for shape measurement in reverse engineering. Digitization can be classified into contact and non-contact type according to the measurement devices. Important thing in digitization is speed and accuracy. The former is excellent in speed and the latter is good for accuracy. Sensor fusion in digitization intends to incorporate the merits of both types so that the system can be automatized. Firstly, non-contact sensor with vision system acquires coarse 3D point data rapidly. This process is needed to identify and loco]ice the object located at unknown position on the table. Secondly, accurate 3D point data can be automatically obtained using scanning probe based on the previously measured coarse 3D point data. In the research, a great number of measuring points of equi-distance were instructed along the line acquired by the vision system. Finally, the digitized 3D point data are approximated to the rational B-spline surface equation, and the free-formed surface information can be transferred to a commercial CAD/CAM system via IGES translation in order to machine the modeled geometric shape.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.10
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• pp.1979-1989
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• 1992

An experimental study has been performed to investigate the horseshoe vortex system formed around cylindrical obstacles mounted vertically on the surface over which a boundary layer is formed. To measure the mean velocity of the flow field, a five-hole Pitot tube has been used. In addition, surface static pressure measurements and surface flow visualization were also performed. From the five-hole probe measurements, vorticity distribution was deduced numerically and the streamwise velocity distribution was also examined. To consider the effect of the leading-edge shape on the formation of the horseshoe vortex, a qualitative comparison was made between the three-dimensional flows around a circular cylinder and a wedge-type cylinder. The five-hole probe measurements showed a single primary vortex which exists immediately upstream of the obstacles, and endwall flow visualization showed the existence of a corner vortex. As the vortex passes around the obstacle, the vortex strength is reduced and the vortex core moves radially outward. Due to this horseshoe vortex, the fluid momentum is found to decrease along the streamwise direction. Since the horseshoe vortex formed around a wedge-type cylinder has weaker strength and is confined to a narrower region than that around a circular, the possibility that the secondary flow loss due to the horseshoe vortex can be reduced through a change of the leading- edge shape is proposed.

• Journal of the Korean Society for Nondestructive Testing
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• v.27 no.5
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• pp.393-397
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• 2007

Eddy current standard including an artificial slot for the calibration of absolute type surface probe was fabricated. Developed eddy current standard has the electric conductivity and dimensions, and contains artificial slot as established in ASTM E 1629. The width and depth of artificial slot are 0.1 mm and 0.5 mm respectively. This slot was only possible to measure the depth on the two side edges, and impossible for the middle part with general measurement tools. The ultrasonic test method was applied for measuring depth of the middle part of the artificial slot in the standard. Using this method the dimension could be measured successfully with uncertainty about $15\;{\mu}m$. Calibration of eddy current standard for the absolute probe can be performed by this technique.

• Journal of the Korean institute of surface engineering
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• v.32 no.4
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• pp.513-520
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• 1999

In this study, we investigated the effects of variously configured magnets on the characteristics of the plasmas to enhance plasma uniformity and density of an inductively coupled plasma source. As the magnets, Helmholtz type axial electromagnets and various multi-dipole magnets types around the chamber wall were used. To characterize the plasma as a function of the combination of the magnets and magnetic field strengths, ion density, electron temperature, and plasma potential were measured using an electrostatic probe along the chamber diameter for Ar plasmas. The measured maximum ion densities were $8$\times$10^{ 11}$$cm^{-3}$ with 600W inductive power and at 5mTorr of operational pressure and the uniformity of ion density was less than 5.9% at 2mTorr of operational pressure. The combination of an optimized multi-dipole magnet type and an axial electromagnet showed the lowest electron temperature (3eV) and plasma potential ($34V{p}$ )