• Proceedings of the KIEE Conference
• /
• 1998.07d
• /
• pp.1498-1499
• /
• 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.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1997.10a
• /
• pp.245-248
• /
• 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.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.20 no.3
• /
• pp.697-700
• /
• 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.

• Proceedings of the KIEE Conference
• /
• 1997.07d
• /
• pp.1522-1524
• /
• 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
• /
• 2007.06a
• /
• pp.244-244
• /
• 2007

• Proceedings of the Korean Vacuum Society Conference
• /
• 2004.02a
• /
• pp.144-144
• /
• 2004

• Analytical Science and Technology
• /
• v.11 no.5
• /
• pp.360-365
• /
• 1998

We have studied structural characterization, electrical charge and discharge, and impedence properties for the $LiMn_2O_4$ synthesized by solid state reaction. From the X-ray diffraction results, diffraction patterns for compounds of the four kinds of $LiMn_2O_4$ compounds were observed to peaks of (111), (311), (004) and (400). Also, Small similar peaks (110), (222) and (313) were observed for sample C1 and C2. Concerning to new peaks of (113) and (331) for the sample C4, we can found that structural transitions were accompanied from C1 and C2 to C4 via C3 structure. A electrical charge and discharge data showed that efficiency of C1 was very poor state and efficiencies of C2 and C3 were about 60-70% of theoretical capacity. But, the C4 showed good charge and discharge properties of more than 70% of theoretical capacity. From the impedence properties for finding the effect of ions and electrons transfer of battery, C2 and C3 of high frequency of real number showed good electrical impedence properties.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2009.10a
• /
• pp.165-166
• /
• 2009

• Journal of the Korean Magnetics Society
• /
• v.7 no.3
• /
• pp.134-139
• /
• 1997

Magneto-impedence (MI) were measured in amorphous $Co_{66}Fe_4NiB_{14} Si_{15}$ ribbons at 100 kHz as a function of the angle from ribbon axis. The samples were prepared using etching method, with the angle deviated from ribbon axis, 0$^{\circ}$, 30$^{\circ}$, 45$^{\circ}$, 60$^{\circ}$ and 90$^{\circ}$. The MI measured in 60$^{\circ}$ sample increased with the increasing magnetic fields. The dip in profile appears at H = 0 above the angle of 30$^{\circ}$. The maximum values of MI and their dips are increased with the cutting angle, but the maximum value of MI decreased at 90$^{\circ}$. The increase of MI with the angle was analyzed in terms of the transverse magnetic permeability.

• Restorative Dentistry and Endodontics
• /
• v.15 no.2
• /
• pp.127-133
• /
• 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.