• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 D
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• pp.1498-1499
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• 1998

Thin film inductors of 10 mm ${\times}$ 10 mm with spiral pattern of 14 turns were fabricated by sputtering, photo-masking, and etching processes. Their impedence characteristics and annealing after effects were investigated. After magnetic annealing, the impedence characteristics of the inductors were improved at comparatively low frequencies, but the tendencies of it for thr frequency changes were almost same. These improvement was caused by the annihilation of the internal stresses of films, Uniaxial field annealed thin film inductor had an inductance of 1000 nH, resistance of 6 $\Omega$, and quality factor of 1 at 2 MHz.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 추계학술대회 논문집
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• pp.245-248
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• 1997

The distilled water is used for the ultrasonic wave propagating material in the measurements of broadband ultrasonic attenuation (BUA) that is applied in industrial and medical applications, The acoustic impedance of water is significantly changed with its temperature. Therefore, the quantitative evaluation of BUA with temperature and the ultrasonic wave propagating distance is highly needed. In this study, we evaluated the variation of attenuation with change in temperature. To measure the variation of BUA in the low frequency region at the temperatures, 27$^{\circ}C$, 29$^{\circ}C$, and 31$^{\circ}C$, we tested the Plyethylene, Teflon, MC-Nylon, Urethane specimens and analyzed the center frequency, frequency bandwidth, spectral peak amplitude. The results showed that BUA value appeared to be lower with increasing temperature. This may be due to the fact that the frequency feature of ultrasonic wave is affected by not only the specific gravity, acoustic impedence, but material crystalline, porosity, the distance of ultrasonic wave propagation in water.

• 동의생리병리학회지
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• 제20권3호
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• pp.697-700
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• 2006

This study was aimed at finding out changes in body composition of obese patients, such as body weight, body fat mass and lean body mass. The subjects of this study are 33 females and 6 males who are from obesity clinic at Gunsan medical center. We measured body composition using BIA(Bioelectrical Impedence Analysis) to compare pre-treatment with post-treatment. The measured data were analyzed by paired t-test using SPSS. Differences were considered significant at P<0.05. Body weigh, body fat mass and lean body mass were reduced each by $3.76{\pm}23.41{\;}kg,{\;}2.29{\pm}1.96kg{\;}and{\;}1.59{\pm}1.38kg$ at a significant level after 4 week-treatment.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 C
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• pp.1522-1524
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• 1997

In this paper, we measured the impedence |Z| and phase angle $\theta$ using the Impedence Analyzer (Hp 4192A). When frequency is varied to produce resonance, the curves(admittance diagram) are obtained. The resonant frequency is obtained also. We analyzed the operating characteristics of quartz crystal coated with sensitive LB films. That is the size of circle in the admittance diagram is decreased as to coat sensitive LB films on the quartz crystal. The resonant frequency and resistance is changed with coating on the surface.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 춘계학술대회
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• pp.244-244
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• 2007

• 한국진공학회:학술대회논문집
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• 한국진공학회 2004년도 제26회 학술발표회 초록집
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• pp.144-144
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• 2004

• 분석과학
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• 제11권5호
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• pp.360-365
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• 1998

고상 반응법에 의하여 합성된 $LiMn_2O_4$를 구조적인 특성과 전기적인 충방전 특성과 임피던스 특성에 대하여 연구하였다. X-선 회절 분석 결과에 의하면 4가지 형태의 화합물 모두가 $LiMn_2O_4$의 주요 회절선인(111), (311), (004)와 (400)이 모두 일치하여 나타났다. C1과 C2는 유사하게 (110), (222) 및 (313)의 회절선이 미소하게 나타났음을 알 수 있었다. C4의 경우는 (113)이나 (331)과 같은 새로운 회절선이 나타난 것으로 보아 C1과 C2의 구조에서 C3의 구조를 거쳐서 C4의 구조로 구조변환이 일어나는 과정임을 알 수 있었다. 전기적인 충방전 특성으로 부터 C1의 경우는 충전 방전 특성이 아주 저하된 상태를 나타내었으며, C2와 C3의 경우는 유사하게 나타났으나, 이들은 이론용량에 60-70%의 범위에 미치는데 그쳤다. 그러나 C4의 경우는 이론 용량의 70% 이상을 나타내는 좋은 충전 방전 특성을 나타냄을 알 수 있었다. 전지의 이온이나 전자 전달의 효과를 알아보기 위하여 임피던스의 특성으로부터 실수부의 파장이 높은 부근에서 형성된 C2과 C3의 경우는 비교적 좋은 특성을 보이고 있음을 알 수 있었다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2009년도 추계학술대회 논문집
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• pp.165-166
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• 2009

• 한국자기학회지
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• 제7권3호
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• pp.134-139
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• 1997

비정질 $Co_{66}$Fe$_{4}$NiB$_{14}$Si$_{15}$에서 리본의 종방향에 대하여 여러 가지 각도를 갖는 시편을 식각법으로 제작하여 100 kHz의 교류전류에서 4 단자법으로 MI 신호를 측정하였다. H=0 근처에서 30 .deg. 시편부터 dip이 나타났으며, 그 크기는 각도에 따라 단조증가하였다. 자기장 크기에 따라 Mi 신호는 증가하였고, 일정한 자기장에서 식각각도에 따라 MI 신호는 증가하다가 90 .deg. 시편에서 감소하였다.

• Restorative Dentistry and Endodontics
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• 제15권2호
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• pp.127-133
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• 1990

Electronic working length determination is based on the electrical impedence between the root canal and the periodontal ligament Different canal irrigants with different electric conductivity may effect on the accuracy of the electronic mechanism. 0.9% Saline, 2.5% NaOCl and 3% $H_2O_2$ were evaluated either in wet or in dry condition. The results were as follows. 1. The electrical resistance mearured by Impedence Meter (Model #253, portland, USA) were 1 $K{\Omega}$ in 0.9% Saline, 0.1$K{\Omega}$ in 2.5% NaOCl and 48 $K{\Omega}$ in 3% $H_2O_2$. 2. Saline measured -0.57mm from the actual canal length and had significant difference. When dried with paper points, however, it measured -0.25mm demonstrating no statistical difference. 3. 2.5% NaOCl measured -4.07mm in wet and -2.26mm in dry condition and both showed significant difference from the actual canal length. 4. 3% $H_2O_2$ measured +0.02mm in wet and -0.09mm in dry canals and both appeared to be within acceptable range for the electronic working length mechanism.