• 한국표면공학회지
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• 제41권4호
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• pp.147-155
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• 2008

The dental orthodontic wire provides a good combination of strength, corrosion resistance and moderate cost. The purpose of this study was to investigate the effects of TiN and ZrN coating on corrosion resistance and physical property of orthodontic wire using various instruments. Wires(round type and rectangular type) were used, respectively, for experiment. Ion plating was carried out for wire using Ti and Zr coating materials with nitrogen gas. Ion plated surface of each specimen was observed with field emission scanning electron microscopy(FE-SEM), energy dispersive X-ray spectroscopy(EDS), atomic force microscopy(AFM), vickers hardness tester, and electrochemical tester. The surface of TiN and ZrN coated wire was more smooth than that of other kinds of non-coated wire. TiN and ZrN coated surface showed higher hardness than that of non-coated surface. The corrosion potential of the TiN coated wire was comparatively high. The current density of TiN coated wire was smaller than that of non-coated wire in 0.9% NaCl solution. Pit nucleated at scratch of wire. The pitting corrosion resistance $|E_{pit}-E_{rep}|$ increased in the order of ZrN coated(300 mV), TiN coated(120 mV) and non-coated wire(0 mV).

• 융합신호처리학회논문지
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• 제9권2호
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• pp.141-145
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• 2008

길이가 서로 다른 평행선로에 전류가 흐르는 경우, 커먼모드 전류(Common mode current)에 의한 전자파의 방사가 일어난다. 이러한 방사 원리를 이용하여 경량, 소형의 길이가 다른 2소자 선형 안테나가 제안되어 있다. 그러나 이 안테나의 경우 선으로 결합된 구조를 가지기 때문에 제작에 있어서 많은 제약이 따른다. 본 논문에서는 선형 안테나의 단점을 개선하고, 제작과 설계가 용이한 평면 기판에 길이가 다른 2소자 평면 안테나를 설계하고, 광대역(UWB: Ultra Wide Band)의 특성을 가지는 안테나를 설계하였다. 그리고 안테나 소자에 삼각형 패치 S, 노치, 테이퍼를 설계함으로서 방사특성은 다이 폴 안테나와 비슷하나 보다 넓은 대역에서 동작하는 안테나를 제작 할 수 있었다. 그 결과 비대역($VSWR{\le}2$)이 약 58%가 되었다.

• 대한한의학회지
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• 제23권2호
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• pp.97-107
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• 2002

Objective : Acupuncture is a method used to treat many kinds of pain in oriental cultural medicine. Especially when hetero-segmental area acu-points are stimulated, the therapeutic effects of pain control have more critical properties than other methods of acupuncture. However, the mechanism of pain control by acupuncture is contradictory so far. The present study examined the effects of electroacupuncture (EA) applied to the acu-point of the hetero-segmental area on modulation of formalin-induced pain in Sprague-Dawley rats. Methods : In order to apply EA to acu-points in the plantar area of right forepaws, a pair of Teflon-coated stainless steel wires were implanted in HT 7 (Shin-Moon) and PC 7 (Dae-Reung) 7 days before the behavioral test. A behavioral test was performed by means of video camera after injection of 5% formalin ($50{\;}\mu\textrm{l}$) into the lateral plantar region of the left hind paw. EA was delivered by a constant DC current stimulator at 4~5 mA, 2 ms, and 10 Hz for 30 min. c-Fos protein expression was measured in the lumbar spinal cord at 2 hr and 4 hr after formalin injection. Results : Behavioral responses including favoring, flinching and biting occurred in the biphasic pattern, such as the 1st phase (0~5 min) and the 2nd phase (20~45 min) after formalin injection. However, EA (4~5 mA, 2 ms, 10 Hz) significantly inhibited the behavioral responses. Injection of formalin expressed c-Fos protein on the ipsilateral dorsal horn neurons in L3 - L5 and the expression was sustained more than 4 hrs after formalin injection. However, EA decreased c-Fos protein expression at dorsal horn neurons in the lumbar spinal cord till 4hrs after formalin injection. Conclusions : These results suggest that EA modulates formalin-induced pain and this inhibitory action may be elicited by the descending inhibitory system.

• 디지털융복합연구
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• 제15권5호
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• pp.325-331
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• 2017

본 연구의 목적은 선택적 시각이라는 이론을 바탕으로 시네마그래프(Cinemagraph) 광고 사례를 통하여 멀티미디어 정량분석, 스토리 정성분석 등의 시네마그래프 분석 모델을 제시하고자 한다. 분석대상은 2016년 대중적인 인지도가 높은 광고모델이 출연한 G마켓의 시네마그래프 시리즈 영상 광고이고, 연구방법은 문헌연구, 국내외 인터넷 매체 분석, 사례연구 등이다. 분석결과 시네마그래프 동선의 비중은 10% 내외가 가장 효과적인 무빙의 형태로 나타났다. 동영상의 전체적인 움직임 보다 시네마그래프의 부분적인 동적인 음직임이 더 큰 시각적 몰입효과를 주고 있었다. 무빙의 방향성은 모델이 제품을 사용하는 동선과 대략적으로 일치하였다. 주제부와 주변부는 한가지 포인트 또는 두가지 포인트 내에서 활용되고 있었다. 스토리의 개연성은 짧은 순간에 모델과 제품의 단순 동작을 표현하고 있다. 멀티미디어의 정량적 분석을 위하여 공간의 비중, 동작의 방향성을 스토리의 정성적 분석을 위하여 주제부와 주변부, 스토리의 개연성 등의 네가지 측면을 고려대상으로 하였다.

• 대한족부족관절학회지
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• 제14권1호
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• pp.5-10
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• 2010

Purpose: This study was performed to compare the contact area between three different correcting angles after the proximal crescentic and Ludloff osteotomies of the first metatarsal. Materials and Methods: We used the two sawbone models. Proximal crescentic (PCO) and Ludloff osteotomies (LO) were performed and secured using K-wires under the correcting intermetatarsal angle (IMA) $5^{\circ}$, $10^{\circ}$, and $15^{\circ}$. Then each 6 osteotomized model was scanned five times and measured the contact area using the calculating program. We excluded the highest and lowest values. Results: The mean area of cutting surface was 189 $mm^2$ in PCO, 863 $mm^2$ in LO. The mean contact area (contact ratio; contact area $\times$100/area of cutting surface) of PCO was 149 $mm^2$ (79%) in $5^{\circ}$, 139.5 $mm^2$ (74%) in $10^{\circ}$, 107 $mm^2$ (57%) in $15^{\circ}$ IMA. The mean contact area (contact ratio) of LO was 711 $mm^2$ (82%) in $5^{\circ}$, 535.5 $mm^2$ (62%) in $10^{\circ}$, 330 $mm^2$ (38%) in $15^{\circ}$ IMA. Conclusion: A significant decrease in the contact area and contact ratio according to increase in correcting IMA was noticed in LO. We recommend the PCO rather than LO, when the IMA is needed to correct over $15^{\circ}$.

• 대한족부족관절학회지
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• 제17권1호
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• pp.45-51
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• 2013

Purpose: The purpose of this study was to compare and analyze the results of midfoot arthrodesis with locking plate fixation and the other instruments. Materials and Methods: Twenty one patients, a total of 22 feet who underwent midfoot arthrodesis at our institution were reviewed retrospectively from January 2006 to December 2011. Locking plates were used in 9 cases, and the other instruments such as K-wires, screws, staples were used in 13 cases. Radiologic union time was evaluated and compared between both groups. Preoperative & postoperative AOFAS midfoot scores were evaluated and compared as clinical results. Results: The average AOFAS score was rising from 69.7 to 89.4 in locking plate group and from 67.6 to 80.7 in the other instrument group. There was no statistically significant difference in two groups (p=0.179). The mean radiologic union time was 10.2 weeks in locking plate group, 12.6 weeks in the other instrument group with no significant difference (p=0.062). One case of peroneal nerve irritation was detected as a complication in locking plate group. One case of peroneal nerve irritation and 1 case of superficial wound infection with skin sloughing were detected in the other instrument group. Conclusion: There was no statistically significant difference for union time and clinical results in both groups. A locking plate can be one of the useful option for midfoot arthrodesis.

• 감성과학
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• 제9권4호
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• pp.377-383
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• 2006

본 연구는 섬유 소재에 IT기술을 적용하는 디지털 의류 제품 중 하나로 여성 재킷에 MP3기능을 내장시켜 상용화 할 수 있는 디자인 모형을 개발하는 것이다. 이를 위하여 선행 연구 고찰 및 5가지 MP3 기능 스마트 의류 초기 모형의 착의 평가 및 사용성 평가 결과를 반영하여, MP3 입력장치 및 모듈의 위치, 이어폰선과 신호선의 경로 등을 최적화하고 직물 기반의 신호선과 입력 장치를 이용함으로써 사용자 중심의 인터페이스와 사용성 및 동적 착용성을 갖춘 MP3 기능 스마트 재킷의 상용화 모형을 개발하였다. 이는 10대 후반부터 20대 초반까지의 여성복 시장을 겨냥한 것으로 최근의 패션 트렌드와 소비자의 감성적 만족도 그리고 디지털 의류 제품으로서의 가치를 고려해 볼 때 상품적 효용이 매우 높을 것으로 예측된다.

• Progress in Superconductivity
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• 제13권1호
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• pp.1-6
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• 2011

Measurement of magnetic signals generated from electric activity of myocardium provides useful information for the functional diagnosis of heart diseases. Key technical component of the magnetocardiography (MCG) technology is SQUID. To measure MCG signals with high signal-to-noise ratio, sensitive SQUID magnetic field sensors are needed. Present magnetic field sensors based on Nb SQUIDs have field sensitivity good enough to measure most of MCG signals. However, for accurate measurement of fine signal pattern or detection of local atrial fibrillation signals, we may need higher field sensitivity. In addition to field sensitivity, economic aspect of the SQUID system is also important. To simplify the SQUID readout electronics, the output voltage or flux-to-voltage transfer of SQUID should be large enough so that direct measurement of SQUID output can be done using room-temperature preamplifiers. Double relaxation oscillation SQUID (DROS), having about 10 times larger flux-to-voltage transfers than those of DC-SQUIDs, was shown to be a good choice to make the electronics compact. For effective cancellation of external noise inside a thin economic shielded room, first-order axial gradiometer with high balance, simple structure and long-baseline is needed. We developed a technology to make the axial gradiometer compact using direct bonding of superconductive wires between pickup coil and input coil. Conventional insert has mechanical support to hold the gradiometer array, and the dewar neck has equal diameter with the dewar bottom. Boiling of the liquid He can generate mechanical vibrations in the gradiometer array due to mechanical connection structure. Elimination of the mechanical support, and direct mounting of the gradiometer array into the dewar bottom can reduce the dewar neck diameter, resulting in the reduction of liquid He consumption.

• Journal of Welding and Joining
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• 제17권5호
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• pp.47-54
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• 1999

It is well known that solidification cracking often occurs in welds of root pass for one-side welding under the conditions of high welding currents and speeds. In this study, the solidification in 590MPa class steel for pressure vessels SPPV490 was investigated by using flux-cored arc welding(FCAW) with 4 types of welding wires and welding conditions of 200∼280A and 2.8∼ 4.2mm/sec. In order to compared the result of cracking in SPPV490, 0.2%C steel for welded structure of SWS400 and 0.45%C steel for machine structural SM45C were also used as base metals. As the results, all the cracks formed in some welding conditions were observed near the center of weld bead. The solidification cracks were generally initiated near the upper surface of bead and propagated toward the inner part. The solidification cracking generally increased with welding current and welding speed in the same base metal and welding material. In cracking susceptibility, SPPV490 showed higher cracking susceptibility than SWS400 in all welding conditions and welding materials. It was considered that cracking susceptibility could not be evaluated with the hardness of weld metals. The cracking ratio increased with decreasing of a/b(a and b; the width of the upper surface and the back surface of the bead) as shape factor of bead. The cracking tendency with shape factor of bead was extended under the condition of higher welding currents.

• 한국항공우주학회지
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• 제39권6호
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• pp.535-542
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• 2011

위성항법시스템은 다양한 분야에서 활용되고 있으며 정밀한 위성항법 위치 정보를 이용하여 자율주행차량(AGV: Autonomous Guided Vehicle)에 활용하는 연구가 진행되고 있다. 위성항법을 이용하여 AGV를 제어하는 경우 지상 시설의 설치 없이 위성항법 기반의 위치 정보를 저장하여 주행 경로를 설정하므로 기존 AGV에 비해 주행 경로 설정이 효율적이다. 특히 주행 경로 상에 장애물이 감지된 경우 기존 AGV의 경우 정해진 경로만을 주행하므로 정지해야만 한다. 그러나 위성항법 기반 AGV는 장애물을 피할 수 있는 주행 경로를 설정할 수 있으므로 연속적인 주행이 가능하다. 본 논문에서는 레이저 스캐너와 회피 벡터를 이용한 회피 경로 설정 알고리즘을 이용하여 위성항법 기반 AGV의 충돌 회피 시스템을 구성한 후 그 성능을 분석하였다.