• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 춘계학술대회논문집
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• pp.81-84
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• 2007

In this paper, fiber optic sound and vibration monitoring sensor which is latticed shape structure based on Sagnac interferometer is fabricated and tested in laboratory conditions. To detect external vibrations surface mounted fibers on the latticed steel wire fence with a dimension of 170cm by 180cm is used. To detect external sound frequency the tightened fiber optic itself wire netting fence with a dimension of 50cm by 50cm is used. Experiments for the detection of the excited vibration and sound signals were performed. A small vibrator induced external vibration signal and it is applied to the latticed structure in the range of 100Hz to several kHz. External sound signal applied to the fiber optic sensor net using non-directional sound speaker. The detected optical signals were compared and analyzed to the detected both accelerometer and microphone signals in the time and frequency domain. Based on the experimental results, distributed fiber optic sensor using Sagnac interferometer detected effectively external vibration and sound signal and had a good performance. This system can be expanded to the monitoring of a significant system and to the structural health monitoring system.

• Journal of Advanced Marine Engineering and Technology
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• 제35권2호
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• pp.196-203
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• 2011

유체 유동에 수직인 방향으로 반복적 리브이 설치된 사각 채널에서 열전달 계수와 마찰계수를 측정하기 위해 실험을 수행하였다. 시험부의 치수는 198 mm(폭)과 40 mm(높이) 그리고 길이가 712mm인 직사각형 채널이다. 시험부 채널의 형상비는 4.95이고 수력 직경 $D_h$은 6.66 cm이었다. 4종류의 와이어 스크린 리브(rib)과 한 개의 일체형 리브을 사용하였다. 0.1 mm 두께의 스테인레스 강판 히터와 T형 열전대를 사용하였다. 레이놀즈 수의 범위는 20,000에서 60,000이었다. 수력직경($D_h$)과 리브의 높(e)이 비($e/D_h$)는 0.075이고 리브 간격(p) 대 높이(e)으 비(p/e)는 10이다. 연구결과 일체형 리브이 누셀트수와 마찰계수 모두 가장 컸다.

• 대한두개안면성형외과학회지
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• 제12권1호
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• pp.28-32
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• 2011

Purpose: A cranioremodeling helmet for correcting plagiocephaly was recently developed. However, no discrete objective methods to evaluate how the deformity is being corrected have been developed. We have established an easy and cost-effective method that can be used not only to show the correction process, but can also be used by physicians to assess the degree of plagiocephaly two-dimensionally. Methods: For two-dimensional evaluation, a length of malleable memory wire (2 mm in diameter) resembling "Sun-Wukong's headband" was placed on the patient's head. The wire around the patient's head was positioned on a plane including points 1 cm above the eyebrow and 1 cm above the auricle. The wire was placed on a sheet of paper and the outline was marked using pens of various colors during each visit. The degree of plagiocephaly correction could then be shown to the patient's parents at every consultation. Results: The method established by the present study easily shows the horizontal cross-section transformation of the head, illustrates plagiocephaly correction by the helmet, and shows the degree of correction in a two-dimensional manner. Conclusion: A soft-shell helmet is widely used for correcting plagiocephaly. However, evaluating the effectiveness of the helmet has been determined in a subjective manner, and a more objective method is now in demanded. Our study found that a "Sun-Wukong's headband" wire can accurately measure two-dimensional changes. Future studies will be required to identify landmarks needed for assessing plagiocephaly correction.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1997년도 춘계학술대회 논문집
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• pp.222-224
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• 1997

This study is about a connective method of High Tc wire for long wire. We prepared silver-sheathed BiPbSrCaCuO wires by the powder-in-tube method. Since the superconducting wires are ceramic, it is very hard to connect each other. In this study, we used a silver sleeve to contract wires and pressed them by various preasures. Then optimum preasure was 9,000 Kgf/$\textrm{cm}^2$ to get the high critical current. The higest critical current was 10A.

• Archives of Plastic Surgery
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• 제48권4호
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• pp.392-394
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• 2021

A 33-year-old man presented to the plastic surgery department for foreign body removal 1 month after the insertion of a continuous glucose monitoring (CGM) sensor (Dexcom G5) in the left upper arm. The patient had used the CGM system for 5 years, and the insertion was done in the usual manner. The entire sensor wire was visible on simple radiography and ultrasonography. In the operating room, and the sensor wire was identified in the intermuscular septum and removed. No foreign body reaction or inflammatory signs were found around the CGM, and the extracted wire measured 2.5 cm. Thus, it was assumed that the whole sensor wire was detached from the transmitter, not fractured. No remnant foreign body was observed on follow-up simple radiography.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.632-635
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• 2001

Microcrystalline Si films have been deposited by using five W-wire filaments of 0.5 mm diameter for hot-wire chemical vapor deposition (HWCVD). We compared the HWCVD grown films with the film exposed to transformer couple plasma system for the modification of seed layer. W-wire filament temperature was maintained below 1600$^{\circ}C$ to avoid metal contamination by thermal evaporation at the filament. Deposition conditions were varied with H$_2$dilution ratio, with and without plasma treatment. From the Raman spectra analysis, we observed that the film crystallization was strongly influenced by the H$_2$dilution ratio and weakly depended on the distance between the wire and a substrate. We were able to achieve the crystalline volume fraction of about 70% with an SiH$_4$/H$_2$ratio of 1.3%, a wire temperature of 1514$^{\circ}C$, a substrate separation distance of 4cm, and a chamber pressure of 38 mTorr. We investigated the influence of ${\mu}$c-Si film properties by using a plasma treatment. This article also deals with the influence of the H$_2$dilution ratio in crystallization modification.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집
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• pp.67-73
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• 2002

The development of high performance HTS wire is a key factor for various electrical applications of coils and cables. The purpose of this paper is to review and consider the main manufacturing technologies of HTS wire and its current status. A lot of efforts have been focused on the optimization of PIT parameters for Bi-2223/Ag wire. According to this, long Bi-2223 wires having Ic of 130 A were recently produced and their mass production has been underway in US. The current status performance of Bi-2223 wire is supposed to be used in power transmission cable because of its lower self-field property. Y-123 second generation conductor is extensively being developed throughout the world and many fabrication processes are competed with each other. 30 m-long Y-123 wire with Ic of 0.8 MA/$\textrm{cm}^2$ was recently fabricated using IBAD and PLD techniques in Japan. This result offers promise of scalable processing of practical multi-layer coated conductor.

• 한국초전도ㆍ저온공학회논문지
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• 제9권1호
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• pp.43-46
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• 2007

Solenoid coil is one of the commonly used one in superconducting power machines because it can produce uniform magnetic field at the center of the coil. Most of the AC loss in a solenoid coil is magnetization loss which is generated by the perpendicular magnetic field. This paper compares the electrical characteristics of two solenoid coils made of YBCO wire and BSCCO wire. We made and tested the BSCCO solenoid coil and YBCO solenoid coil which had the same number of turns and inner diameter. Number of turns and inner diameter of both coils were 30 turns and 10cm, respectively. AC loss of both coils were calculated by using the finite element method. Result shows that AC loss of YBCO coil was about 1/7 of that of the BSCCO coil when the current was 40A.

• 한국전자파학회논문지
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• 제26권4호
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• pp.389-396
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• 2015

펄스 유도(Pulse Induction) 방식의 금속 탐지기 코일 설계에 대하여 살펴보았다. 0.3 mm, 0.5 mm, 1.0 mm의 직경을 갖는 도선과 $30cm{\times}30cm$ 및 $35cm{\times}35cm$ 크기의 유전체 탐지판을 이용하여 탐지 코일을 제작하였고, 코일 크기와 코일 감은 수 등의 파라미터 변화에 따른 코일 시정수 및 코일 전류 등의 특성을 살펴보았다. 도선의 직경, 코일 크기 및 코일 감은 수 변화에 따른 코일의 인덕턴스, 저항 및 시정수 값에 대하여 계산 결과와 측정 결과를 비교 분석하였다. 또한, 입력 펄스폭 변화에 따른 탐지 코일의 전류 변화에 대하여 계산 결과와 측정 결과를 비교 분석함으로써 펄스 유도 방식의 금속탐지기 코일 설계에 대하여 논하였다.

• 한국세라믹학회지
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• 제33권4호
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• pp.471-477
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• 1996

During Bi(Pb)-Sr-Ca-Cu-O superconductor wire fabrication the effect of the initial packing density on the final characteristics of superconductor wire was systematically studied. To increase the powder packing density with uniform distribution of superconducting core a billet insertion method processed by CIP was applied instead of the commonly used vibration and ramming method of powder insertion into silver sheath. Compared with the vibration and ramming method the billent insertion technique processed by CIP cause the 30% incre-specimen with 130${\mu}{\textrm}{m}$(core thickness : 45 ${\mu}{\textrm}{m}$)and 5.24 mm width processed at 84$0^{\circ}C$for 200hrs. shows specimen with 130${\mu}{\textrm}{m}$ (core thickness ; 45${\mu}{\textrm}{m}$)and 5.24 mm width processed at 84$0^{\circ}C$ for 200 hrs. shows maximum 34A for Ic and 16, 700 A/cm2 for Ic measured at 77K and 0T. Also the sample rolled 3 times shows maximum 7, 2A for Ic and 11, 000 A/cm2 for 77K and 0T. Based on X-ray experimental results the formation of Bi-2223 and texture were significantly well developed at the interface between the superconducting core and silver sheath as compared with those of the interior area of superconducting core.