• Journal of the Korean Magnetics Society
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• v.5 no.1
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• pp.38-41
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• 1995

The effects of Nb and Cu additives as will as substitutional Co into $Nd_{4}Fe_{85.5}B_{10.5}$ melt-spun alloy were studied aiming for finding a $\alpha$-Fe based Nd-Fe-B composite alloys with high energy product. The addition of Nb and Cu to $Nd_{4}Fe_{85.5}B_{10.5}$ decreased the average grain size and increased the coercivity up to 207kA/m(2.6kOe), Further-more, the substitution of Co for Fe in $Nd_{4}Fe_{82}B_{10}Nb_{3}Cu_{1}$ alloy resulted in the decrease of the average grain size (<20nm) and improved the hard magnetic properties. The remanence, coercivity and energy product of optimally annealed $Nd_{4}Fe_{74}Co_{8}B_{10}Nb_{3}Cu_{1}$ alloy were 1.345, 219kA/m(2.75kOe) and $95.5kJ/m^{3}$(12MGOe), respectively.

• Journal of the Korean Geotechnical Society
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• v.29 no.7
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• pp.5-15
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• 2013

Clogging phenomenon is one of the important problems in deteriorated tunnels, and it caused inhibition of drainage system by long-term behavior. Clogging phenomenon is mainly composed of $CaCO_3$ in the form calcite. Calcite is generally created by the reaction of $Ca(OH)_2$ with $CO_2$ emitted from vehicles. The structure of deteriorated tunnels was simulated and the setting of outflow from drainage pipe was observed in this study. The test was experienced by changing the slope of drainage system because existing drainage system was pracitced almost below $5^{\circ}$. As a result, in case of drainage system's slope is $2^{\circ}$, Quantum Stick has an effect for prohibiting scale in drainage system, but magnetic treatment was not effective. As a result, in case of drainage system's slope is $5^{\circ}$, both technologies were effective for prohibiting scale in drainage system, but Quantum Stick was especially more effective than magnetic treatment.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.05a
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• pp.602-607
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• 2002

In this paper, we proposed an approach to efficiently compress and transmit multiresoltion 3D lariat models for multimedia and very low bit rate applications. A personal facial model is obtained by a 3D laser digitizer, and further re-quantized at several resolutions according to different scope of applications, such as animation, video game, and video conference. By deforming 2D templates to match and re-quantize a 3D digitized facial model, we obtain its compressed model. In the present study, we create hierarchical 2D lariat wireframe templates are adapted according to facial feature points and the proposed piecewise chainlet affined transformation(PACT) method. The 3D digitized model after requantization are reduced significantly without perceptual loss. Moreover the proposed multiresoulation lariat models possessed of hierarchial data structure are apt to be progressively transmitted and displayed across internet.

• Journal of the Korean Magnetics Society
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• v.24 no.2
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• pp.56-59
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• 2014

The samples of $Ba_2CoZnFe_{12}O_{22}$ was synthesized by the solid-state reaction method. The toroids of $Ba_2CoZnFe_{12}O_{22}$ were sintered with various sintering temperature at 1050, 1100, 1150, and $1200^{\circ}C$, and studied by x-ray diffractometer, vibrating sample magnetometer, network analyzer, and Mssbauer spectrometer. From the XRD patterns, the density of samples increased with increasing sintering temperature. From the magnetic hysteresis curves up to 10 kOe at 295 K, the saturation magnetization ($M_s$) of $Ba_2CoZnFe_{12}O_{22}$ samples in various sintered at 1050, 1100, 1150 ,and $1200^{\circ}C$ were showed around $M_s$= 33.0 emu/g. However, With increasing sintering temperature, the coercivity ($H_c$) of samples decrease. Complex permeability and permittivity of samples in various sintering temperatures were measured between 100MHz to 4 GHz. With increasing sintering temperature, the permeability of samples increase.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.8
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• pp.2051-2056
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• 2014

This paper investigated the separation of magnetic signal from a ferro-magnetic object. The magnetic signals were ILM(induced longitudinal magnetization) and IVM(induced vertical magnetization), which were induced by earth magnetic field and PLM(permanent longitudinal magnetization) and PVM(permanent vertical magnetization), which were due to a permanent magnetization of the object, respectively. Magnetic signal separation was based on the fact that magnetization vector could be analyzed according to longitudinal and vertical directions. Also the influence of non-uniform magnetic field from a rectangular coil on the separation was examined. A military vessel with a size close to rectangular coil has more errors on the magnetic signal separation.

• Journal of the Korean Magnetics Society
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• v.21 no.5
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• pp.151-156
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• 2011

The influence of thickness on magnetic interaction and magnetic properties in electrodeposited CoPt magnetic films was investigated from the analysis of the magnetic remanence curves and the magnetic hysteresis loops. As the thickness of the CoPt film is increased, the perpendicular coercivity and the saturation magnetization are increased but the squareness is considerably decreased. The analysis results of the magnetic remanence curves and the magnetic hysteresis loops exhibited that the dipolar interaction is the main interaction mechanism for all samples, but the strength of the dipolar interaction gradually increased with increasing sample thickness.

• Journal of the Korean Society of Radiology
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• v.13 no.4
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• pp.581-588
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• 2019

MRI is superior when contrasted to help the organization generate artifacts resolution, but also affect the diagnosis and create a image that can not be read. Metal is inserted into the tooth, it is necessary to often be inhibited in imaging by causing the geometric distortion due to the majority and if the difference between the magnetic susceptibility of a ferromagnetic material or paramagnetic reducing them. The purpose of this study is to conduct a metal artefact in accordance with the analysis using a diamagnetic material. The magnetic material include a wire for the orthodontic bracket and a stainless steel was used as a diamagnetic material was used copper, zinc, bismuth. Testing equipment is sequenced using 1.5T, 3T was used was measured using a SE, TSE, GE, EPI. A self-produced phantom material was used for agarose gel (10%) to a uniform signal artifacts causing materials are stainless steel were tested by placing in the center of the phantom and cover inspection of the positive cube diamagnetic material of 10mm each length.After a measurement artefact artifact zone settings area was calculated using the Wand tool After setting the Low Threshold value of 10 in the image obtained by subtracting images, including magnetic material from a pure tool phantom images using Image J. Metal artifacts occur in stainless steel metal artifact reduction was greatest in the image with the bismuth diamagnetic materials of copper and zinc is slightly reduced, but the difference in degree will not greater. The reason for this is thought to be due to hayeotgi offset most of the susceptibility in bismuth diamagnetic susceptibility of most small ferromagnetic. Most came with less artifacts in image of bismuth in both 1.5T and 3T. Sequence-specific artifact reduction was most reduced artifacts from the TSE 1.5T 3T was reduced in the most artifacts from SE. Signal-to-noise ratio was the lowest SNR is low, appears in the implant, the 1.5T was the Implant + Bi Cu and Zn showed similar results to each other. Therefore, the results of artifacts variation of diamagnetic material, magnetic susceptibility (${\chi}$) is the most this shows the reduced aspect lower than the implant artificial metal artifacts criteria in the video using low bismuth susceptibility to low material the more metal artifacts It was found that the decrease. Therefore, based on the study on the increase, the metal artifacts reduction for the whole, as well as dental prosthesis future orthodontic materials in a way that can even reduce the artifact does not appear which has been pointed out as a disadvantage of the solutions of conventional metal artifact It is considered to be material.

• Applied Chemistry for Engineering
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• v.5 no.3
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• pp.438-442
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• 1994

A very useful cation radical, triphenylaminium hexachloroantimonate, was quantitatively incorporated into insoluble polymer framework. The polymer cation radical was found to be effective as a catalyst in the Diels-Alder type dimerization and then shown to be reusable through several cycles of use.

• Journal of Korean Library and Information Science Society
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• v.31 no.3
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• pp.23-47
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• 2000

이 연구는 전거통제를 위한 상호협력시스템으로서 발전을 거듭하고 있는 미국의 NACO의 역사와 발전과정, PCC와의 관계 등에 대해 고찰하고, 한국의 도서관에서의 활용방안에 대해 구체적으로 분석하였다. 광범위한 전거데이터의 활용이라는 면에서 NACO는 유용한 대안이 될 수 있으나, 표목 및 접근점의 선정과 형식에 관한 표준의 문제, 로마자화의 문제, 수록데이터의 유용성, 비용, 정책상의 문제 등도 충분히 고려해야 함을 지적하였다. 아울러 국내의 경우에도 이와 같은 전거통제를 위한 상호협력시스템이 필요하다는 점에서, NACO는 하나의 좋은 모델이 될 수 있을 것이다.

• VENDING MACHINE INDUSTRY
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• no.autumn
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• pp.15-19
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• 2000

협회에서는 자판산업의 수요 확대와 대외적 소비자 인식제고를 목적으로 내년도에는 산업계 전체를 총망라한 자동판매기 전시회 개최를 기획하고 있다. 20년의 넘은 자판산업의 역사에도 불구하고 지금까지 제대로 된 전시회론 개최하지 못했다는 점은 산업계의 부끄러운 자화상으로 이제는 업계의 적극적인 관심과 참여로 산업발전의 새로운 전기를 마련할 수 있는 전시회를 반드시 개최해야 하는 게 산업계의 시급한 당면과제이다. 이러한 현실에서 협회에서는 내년 전시회 개최의 올바른 방향을 모색하고 업체들의 전시회에 대한 관심도 및 바램을 파악하기 위한 설문조사를 진행했다. 과연 업체의 관심도는 어느 정도이고 성공적인 전시회 개최를 위해서는 어떠한 선결과제들이 해결되어야 하는 지에 대해 집중조명하는 시간을 마련했다.