• Proceedings of the KIEE Conference
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• 1995.11a
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• pp.555-557
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• 1995

In near field optics, optical fiber probe is smaller than the wavelength of light. This small probe makes it possible to overcome the diffraction limit due to wave property of light. In conventional optical systems, the image resolution is governed by wavelength. But in NSOM, it is determined by probe tip size and probe shape. Therefore probe tip size and shape are very important points in near field optics. In this paper, we will suggest the new fabrication methods of optical fiber probe and show that the probe tip size is sub-micrometer using SEM.

• Microbiology and Biotechnology Letters
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• v.31 no.2
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• pp.205-209
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• 2003

Recently, we introduced a new method for rapid screening of bacterial species- or subspecies-specific DNA probes, named “inverted dot blot hybridization screening method”. We then applied this method to develop species- or strain- specific DNA probes for Prevotella intermedia and Prevotella nigrescens. In those studies, among 96 candidate DNA probes which were screened by the new method, 5 probes were confirmed as being putatively strain-specific : 3 probes for P. nigrescens 9336 (ATCC 33563), one for each p. intermedia ATCC 25611 and one for P. nigrescens G8-9K-3 (ATCC 49046). In the present study, we evaluated by Southern blot analysis a DNA probe Pi29-L, one of the 96 candidate probes described above, whether it is specific for the strain ATCC 25611 off. intermedia. Our data show that the probe Pi29-L is potentially P. intermedia ATCC 25611-specific, which can be useful for the detection and identification of the strain, particularly in maintenance of the strain.

• Journal of electromagnetic engineering and science
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• v.17 no.1
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• pp.1-8
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• 2017

This paper introduces a technique to obtain the broadband characteristics of circularly polarized antennas using an L-shaped probe. A waveguide antenna is suitable for obtaining high gain and handling convenience in some applications; however, the asymmetrical structure of the L-shaped probe results in cross-polarization and frequency dependence on the field distribution of higher-order modes (HOM). In addition to the basic characteristics of a waveguide antenna with an L-shaped probe, the author discusses some techniques to reduce the HOM and cross-polarization. As a result, the 3-dB axial ratio (AR) is obtained with the fundamental mode even when the frequency is expanded to the region for HOM of TM. This reduction is mainly due to the cutoff structure to the TM mode around the short wall of the waveguide. Furthermore, some aperture modification techniques can reduce the cross-polarization in a wide range of angles in the radiation pattern. Such techniques and their mechanisms are discussed in this paper. The obtained performance shows that the proposed antennas have a wide range of angles of 3-dB AR in the radiation pattern, broadband characteristics in impedance and AR, and low variation in group velocity.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.172-177
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• 2011

In order to investigate spray characteristics of gas-centered swirl coaxial injectors, a phase detection optical probe is employed to obtain the spatial evolution of the drop size and velocity. From the study on the optical probe responses under various impact angles, it is demonstrated that the drop size and velocity can be measured with an uncertainty less than 15% when the probe axis remains within about ${\pm}15^{\circ}$ of the drop velocity direction. This typical uncertainty is in good agreement with a previous study. It is also shown that the drop sizes measured by the optical probe are in accord with those evaluated by image processing techniques. Finally, the experiments with the optical probe are performed in dense sprays, as it were, in the near field of gas-centered swirl coaxial injectors. Some experimental results are presented and discussed to be of help to understanding of spray characteristics of the injectors.

• Bulletin of the Korean Chemical Society
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• v.31 no.7
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• pp.2031-2035
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• 2010

A triple-probe channel type chemosensor based on an $NO_2S_2$-macrocycle functionalized with phenyltricyanovinyl group was synthesized and its sensing characteristics were examined. The pink-red solution of L changed selectively to pale yellow upon addition of $Hg^{2+}$. The selective fluorometric response of L to all the tested metal ions was studied. The results showed that a large enhancement of the fluorescence of L was observed only in the case of $Hg^{2+}$. In addition, L showed large anodic shift (~ 0.3 V) for the addition of excess $Hg^{2+}$. Through above three observed results by the different techniques, we confirmed that the proposed chemosensor acts as the multiple-probe channel sensing material. The crystal structure of mercury(II) nitrate complexs of L which shows a 1-D polymer network with a formula $[Hg_2(L)_2(NO_3)_2({\mu}-NO_3)_2]_n$ was also reported.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.24 no.6
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• pp.647-652
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• 2015

A probe pin is a key component of LED inspection equipment. The probe pin makes contact with the LED electrodes and supplies an electric current. Because the mechanical and electrical homogeneity of the probe surface affects the service life and reliability, its characterization is essential. For this study, the hardness was measured using a micro-Vickers hardness test. Moreover, the thicknesses of the plating at different locations and the elemental compositions were examined using an FE-SEM. The uniformity of the plating was found to be acceptable because palladium was detected consistently throughout the tested domain. In addition, the hardness of the surface was determined to be higher than that of the typical palladium range, which is attributed to the use of undercoated nickel.

• Journal of radiological science and technology
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• v.46 no.1
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• pp.15-21
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• 2023

This study was purpose to assessment of the resolution characteristics by using ATS 535H Basic quality assurance (QA) phantom for ultrasound. The ultrasound equipment was used Logiq P6 (Ultrasound, GE Healthcare System, Chicago, IL, USA). And the ultrasound transducer were used Convex 4C (4~5.5 MHz), Linear 11L (10~13 MHz), Sector 3SP (3~5.5 MHz) probe. As for the noise power spectrum (NPS) comparison results by using ATS 535H Basic QA ultrasound phantom and Convex 4C, Linear 11L, Sector 3SP probe. The NPS value of the Convex 4C probe image was 0.0049, Linear 11L probe image was 0.0049, Sector 3SP probe image was 0.1422 when the frequency is 1.0 mm^-1. The modulation transfer function (MTF) comparison results by using ATS 535H Basic QA ultrasound phantom and Linear 11L probe the MTF value of the 3 cm focus image was 0.7511 and 4 cm focus image was 0.9001 when the frequency is 1.0 mm^-1. This study was presented characteristics of spatial resolution a quantitative evaluation methods by using ultrasound medical images for QA of ultrasound medical QA phantom. The quality control (QC) for equipment maintenance can be efficiently used in the clinic due to the quantitative evaluation of the NPS and MTF as the standard methods. It is meaningful in that it is applied mutatis mutandis and presented the results of physical resolution characteristics of the ultrasound medical image.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.156.2-156.2
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• 2015

반도체 소자의 크기가 나노사이즈로 줄어들기 때문에, 건식식각의 중요성이 강조되고 있다. dual plasma source를 사용함으로써 plasma 밀도, 이온충돌에너지, 이온플럭스를 조절 가능하다. Low frequency로 이온에너지를 조절하고, high frequency로 이온플럭스를 일반적으로 조절한다. 본 연구는 inductively coupled plasma (ICP)와 capacitively coupled plasma (CCP)를 사용하는 dual plasma source이다. ICP는 AE RPS로 2.4 MHz를 사용하고, CCP는 AE RFX-600으로 13.56 MHz이다. single L-probe는 Hiden ESPion이고, quadrupole mass spectrometer (QMS)는 INFICON CPM-300이다. chuck에 CCP가 인가되고, ICP는 SUS mesh를 거쳐서 영향을 미친다. Gas는 Ar, Ar+CF4 두 조건에서 비료를 하였다. Single L-probe를 이용하여 플라즈마를 측정한 결과 CCP만 인가하였을 때, Te 2.05 eV, Ne 4.07E+10 #/cm3, Ni 5.82E+10 #/cm3의 결과를 얻을 수 있었다. ICP를 방전하고 mesh를 통해서 chuck으로 입사하는 이온을 측정한 결과 mesh에 의해 이온이 중성화되어 거의 입사하지 않음을 확인할 수 있었다. 최종적으로 이온의 영향이 상쇄되고, 라디칼의 영향이 증가하여 높은 etch rate와 선택비를 가지며, 등방성 식각의 영향이 커질 것으로 사료된다.

• Journal of the Korean Society of Visualization
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• v.18 no.3
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• pp.122-128
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• 2020

In the field of experimental fluid dynamics, the 5-hole probe is one of the most widely used tools to measure flow velocity and pressure. We hereby describe the development of an inexpensive laboratory-based flow calibration system for 5-hole probes. The system is applied to a custom L-shaped probe, and the probe performance is compared against a standard commercial probe in a custom wind tunnel. The setup allows rotation of the probe around the yaw and pitch axes. Static and total pressure values are calculated, and then calibration maps are constructed based on the yaw and pitch angles. Using these maps, errors of the custom probe are found to be ±5% for velocity magnitude and ±3° for direction, compared to the commercial probe, when both pitch and yaw angles are within 40°.

• Journal of the Korean GEO-environmental Society
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• v.19 no.3
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• pp.15-24
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• 2018

As electromagnetic waves are affected by electrical conductivity or permittivity, they are widely used to evaluate geotechnical characteristics. In this study, a probe for measuring electromagnetic waves using a time domain reflectometry is manufactured to evaluate heavy metal concentration in saline water. In the experiments, a copper is used as a heavy metal, and a probe is demonstrated with the concentration of copper. Solutions were set for 8 different copper concentration (0, 0.01, 0.05, 0.1, 0.5, 1, 5, 10 mg/L) in saline water with 3% salinity. The probe is coated by electrical insulating materials such as epoxy, top-coat, varnish, acrylic paint, heat-shrinkage tube to measure electromagnetic waves in saline water. The measured signals are compared according to coating material. As results, for probes coated with acrylic paint and heat-shrinkage tube, signal variation is not detected. For epoxy, top-coat, and varnish coated probes, the voltage decreases with an increase of copper concentration. Probes coated by epoxy at once and top coat can estimate under 5 mg/L of copper concentration and the probe coated by epoxy twice can estimate over 5 mg/L of copper concentration. This study shows that the probe using the time domain reflectometry can be used to evaluate the concentration of heavy metal in saline water by coating the probe with insulating material.