• Journal of Magnetics
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• 제13권1호
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• pp.34-36
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• 2008

For the measurement of the magnetic field distribution with high spatial resolution and high accuracy, the magnetic field sensing probe must be non-magnetic, but the MFM probe and sub-millimeter-meter size Hall probe use a ferromagnetic tip and block, respectively, to increase the sensitivity. To overcome this drawback, we developed a micro-size search coil magnetometer which consists of a single turn search coil, Terfenol-D actuator, scanning system, and control software. To reduce the noise generated by the stray ac magnetic field of the actuator driving coil, we employed an even function $\lambda$-H magnetostriction curve and lock-in technique. Using the developed magnetometer, we were able to measure the magnetic field distribution with a magnetic field resolution of 1 mT and spatial resolution of $0.1mm{\times}0.2mm$ at a coil vibration frequency of 1.8 kHz.

• Journal of Mechanical Science and Technology
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• 제15권2호
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• pp.239-247
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• 2001

Measured radiative heat fluxes on the furnace exit plane of a heavy duty power boiler of steam output 1650 T/h are discussed. A high-ash pulverized bituminous coal was used. Such measurements are necessary to improve heat fluxes inside a steam boiler furnace was manufactured. An extra small heat radiation sensor was placed in the water cooled head of the probe. The sensor had no direct contact with furnace gases and measured only the radiant energy. There was no exposure to convective heat transfer. With the radiometric probe, one can obtain a spherical indicatrix of radiation intensity as well as hemispherical radiative heat flux incident on any surface passing through a measuring point inside the furnace. Thus, the quantity of radiation energy, passing through the furnace exit plane, to the convective heating surfaces and the quantity of radiation energy going in the opposite direction were measured. A formula for relative radiative heat flux on the furnace exit plane has been proposed.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1998년도 추계종합학술대회 논문집
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• pp.613-616
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• 1998

In this paper, a model of a Eddy-current probe coil with a ferrite core in the presence of a half-space with a layer is developed. The half-space with a layer is accounted for by computing the appropriate Green's function by using Bessel transforms. Upon introducing equivalent Amperian currents within a core to explain effect to a impedance change in the coil due to a (ferrite) core, we derive a volume integral equation, The integral equation is transformed via the method of moments into a vector-matrix equation, which is then solved using a linear equation solver. Through the above processing, we computed impedance value in a Eddy-current probe coil due to a conductivity change of layer.

• 대한방사성의약품학회지
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• 제4권1호
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• pp.3-10
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• 2018

The folate receptor (FR) is a promising cell membrane-associated target for nuclear imaging of various cancers (via imaging $FR-{\alpha}$) and potentially also inflammatory diseases (via imaging $FR-{\beta}$), through the use of folic acid-based radioconjugates. However, there have been several drawbacks of previously reported radioconjugates, such as a short half-life of the radiolabel ($^{68}Ga\;t_{1/2}$ 68 min), a complex and time-consuming multistep radiosynthesis, and a high renal uptake of radiolabeled folate derivatives. The goal of this study was to develop an imaging probe by directly labeling folate with radioactive iodine without using an extra prosthetic group. The radiolabeling of folate was optimized using various labeling conditions and the labeled tracers were isolated by high-performance liquid chromatography. The in vitro stability of labeled folate was checked in phosphate-buffered saline and serum. The tumor-targeting efficacy of the probe was also evaluated by biodistribution studies using a murine 4T1 tumor model.

• 전자공학회논문지A
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• 제29A권2호
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• pp.68-76
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• 1992

Concurrent Junction process (simultaneous formation of a silicide and a junction on the implanted substrate) by Rapid Thermal Annealig has been investigated. Electrical and material properties of CoSi$_2$ films were analyzed with Alpha Step, 4-point probe, X-ray diffraction(XRD) and Scanning Electron Microscope(SEM). And CoSi$_2$ junctions were examined with Spreading Resistance probe in order to see the redistribution of electrically activated dopants and determined the junction depth. Two step annealing process, which was 80$0^{\circ}C$ for 30sec and 100$0^{\circ}C$ for 30sec in NS12T ambient was employed to form CoSi$_2$ and shallow junctions. Resistivity of CoSi$_2$ was turned out to be 11-15${\mu}$cm and shallow junctions less than 0.1$\mu$m were successfully formed by the process. It was found that the dopant concentration at CoSi$_2$/Si interface increased as decreasing the thickness of Co films in case of $p^{+}/n$ and $n^{+}/p$ junctions while the junction depth decreased as increasing CoSiS12T thickness in case of $p^{+}/n$ junction.

• 융합보안논문지
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• 제10권4호
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• pp.21-30
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• 2010

2010년 가장 중요한 보안 이슈 중 하나는 무선 네트워크이었다. 스마트폰의 보급이 본격화되면서 무선 인터넷 사용자가 급증하였고 무선 AP가 전국에 우후죽순으로 설치되었다. 그러나 대부분의 무선 AP가 보안적인 관점에서 제대로 관리되지 않고 있고 무선랜 이용자 또한 보안의 중요성을 인식하지 못하고 있다. 이러한 상황은 심각한 보안위협을 초래할 수 있다. 본 논문에서는 QR 코드를 통해 악성코드를 유포, 모바일 AP 기능 활성화를 통해 대량 과금을 유발하는 새로운 방식의 사이버 공격 기법을 설계하고 분석하였다. 제안한 새로운 취약점은 안드로이드폰의 모바일 AP 기능을 강제로 활성화시킨 후 주변에서 발생하는 모든 Probe Request에 대해서 응답하게 하여 과금 유발 및 통신 장애를 유발한다.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1998년도 춘계학술발표회논문집(2)
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• pp.216-221
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• 1998

A study on induction plasma deposition with ceramic materials, yttria-stabilized-zirconia ZrO$_2$-Y$_2$O$_3$ (m.p 264O $^{\circ}C$), was conducted with a view developing a new method for nuclear fuel fabrication Before making dense pellets more than 96％TD., the spraying condition was optimized through the process parameters, such as chamber pressure, plasma plate power powder spraying distance, sheath gas composition, probe position, particle size and powders different morphology. The results with a 5mm thick deposit on rectangular planar graphite substrates showed a 97.11％ theoretical density when the sheath gas flow rate was Ar/H$_2$120/20 l/min, probe position 8cm, particle size -75 ${\mu}{\textrm}{m}$ and spraying distance 22cm by AMDRY146 powder. The degree of influence of the main effects on density were powder morphology. particle size, sheath gas composition, plate power and spraying distance, in that order. Among the two parameter interactions, the sheath gas composition and chamber pressure affects density greatly. By using the multi-pellets mold wheel type, the pellet density did not exceed 94%T.D., owing to the spraying angle.

• Journal of Radiation Protection and Research
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• 제24권1호
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• pp.45-53
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• 1999

각 염색체에 특이한 DNA probe를 이용하는 FISH기법은 방사선에 의해 유발된 상호전좌 및 삽입 등의 염색체의 구조적 변화를 측정하는 매우 효과적인 방법으로서 그 활용성이 증가되고 있다. 본연구는 방사선 피폭시 생물학적 선량측정법으로서 FISH기법을 활용하기 위하여 사람의 1, 2, 4번 염색체에 특이한 probe를 이용하여 고선량 단일 피폭시 유발된 각종 염색체 이상빈도를 관찰하고 이를 PAINT분류체계에 의해 분석하였다. 방사선 조사에 의한 염색체 이상빈도는 상호전좌(t)와 이동원염색체(dic)의 수가 선량 증가에 따라 같이 증가하는 것을 알 수 있으며 color junction의 수도 선량에 따라 증가하는 것을 알 수 있었다. 상호전좌의 빈도는 이동원 염색체의 빈도보다 상대적으로 높게 나타났다. 삽입(ins), 무동원염색체(ace), 및 환상염색체(r)의 수도 선량 증가에 따라 같이 증가하는 것을 알 수 있었다. 기존의 염색체재배열 분석방법과 비교해 볼 때 FISH기법은 다양한 형태의 염색체재해열을 보다 쉽게 관찰할 수 있게 하며 생물학적 선량제로서 중요한 역할을 할 것이라 기대된다.

• Journal of Genetic Medicine
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• 제1권1호
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• pp.45-50
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• 1997

Neuroblastoma, a pediatric malignant neoplasm of neural crest origin, has a wide range of clinical virulence. The mechanisms contributing to the development of neuroblastomas are largely unclear, but non-random chromosomal changes identified over the past years suggest the involvement of genetic alterations. Amplification of the human N-myc proto-oncogene is frequently seen either in extrachromosomal double minutes or in homogeneously staining regions (HSRs) of aggressively growing neuroblastomas. N-myc maps to chromosome 2 band 24, but HSR have never been observed at this band, suggesting transposition of N-myc during amplification. We have constructed and analyzed the region-specific painting probe for HSR in neuroblastoma IMR-32 to determine the derivative chromosomes. Microdissection was performed on HSR using an inverted microscope with the help of microglass needles and an micromanipulator. We pretreated the microdissected fragments with Topoisomerase I which catalyzes the relaxation of supercolled DNA, and performed two initial rounds of DNA synthesis with T7 DNA polymerase followed by conventional PCR to enable the reliable preparation of Fluorescent in situ hybridization probe from a single microdissected chromosome. With this method, it was possible to construct the region-specific painting probe for HSR. The probe hybridized specifically to the HSRs of IMR-32, and to 2p24, 2p13 of normal chromosome. Our results suggest there was coamplification of N-myc together with DNA of the chromosome 2p24 and 2p13. Moreover, the fluorescent signals for the amplified chromosomal regions in IMR-32 cells were also easily recognized at a Thus this painting probe can be applied to detect the similar amplification of N-myc in neuroblastoma tissue, and the probe pool for HSR may be used to identify the cancer-relevant genes.

• 한국식품과학회지
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• 제26권1호
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• pp.1-5
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• 1994

쌀전분의 열전도도를 probe method로 측정하였다. 수분함량이 0에서 28.2%로 증가함에 따라 열전도는 약 $0.065{\sim}0.09W/mK$에서 $0.13{\sim}0.23W/mK$로 약 $2{\sim}2.5$배의 큰 증가를 보였다. 밀도가 일정할 때 온도가 $25^{\circ}C$에서 $70^{\circ}C$로 증가함에 따른 열전도는 수분함량이 증가할수록 뚜렷하게 증가하였다. DSC의 측정결과 수분함량 7.2% 이하인 경우는 endothermic peak가 전혀 보이지 않았으며, 그 이상의 수분함량$(7.2{\sim}33.6%)$에서도 매우 완만한 peak를 보여 주었다. 따라서 열전도도에 대한 수분함량-온도의 교호작용은 전분의 호화에 의한 간접적인 영향이라기 보다는 물의 열전도도의 온도의존성에 기인하는 것으로 추측된다. 쌀전분의 열전도도(Ke)는 수분함량 $(M.C.,\;0{\sim}28.2%)$, 충진밀도$(P_{b},\;650{\sim}800\;kg/m^{3})$ 및 온도$(T,\;25{\sim}70^{\circ}C)$와 Ke=-0.111+0.000203 T+0.00173 M.C.+0.000247 $P_{b}+0.000035$ M.C. T의 관계식을 얻어졌다.