• Journal of Korea Multimedia Society
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• v.19 no.7
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• pp.1146-1153
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• 2016

The bioelectrical impedance (BI) at the inner forearms was measured using bioelectrical impedance measurement system (BIMS), which employs the multi-frequency and the two-electrode method. Experiments were performed as follows. First, while applying a constant alternating current of 800A to the inner region of the forearms, BI (Z) was measured at nineteen frequencies ranging from 5 to 500 kHz. The prediction marker (PM) was calculated for right and left forearm. The resistance (R) and the reactance (X_c) were simultaneously measured during impedance measurement. Second, a Cole-Cole plot (relationship between reactance and resistance) was obtained for left and right forearm, indicating the different characteristic frequencies (f_c). Third, the phase angle was obtained, indicating strong dependence on the applied frequency.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.20 no.10
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• pp.68-73
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• 2006

As in the measurement of ground resistance by using the 3 point fall-of-potential method, it is known that the distance of current electrode should be at the point of showing the plateu on the potential curve. But the problem is that it my be practically impossible to meet the condition in actual sites. For solving such a situation, this paper provides the least distance of current electrode according to the analysis for the test-field measurement showing that it is feasible to measure the ground resistance in the two in current electrode distance as the length of driven-rod type electrode and the some district length of mesh electrode.

• Transactions on Electrical and Electronic Materials
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• v.13 no.1
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• pp.35-38
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• 2012

In this study, we have attempted to characterize the photovoltaic effect in real-time measurement of photoinduced current in a poly-Si-based solar cell using photoconductive atomic force microscopy (PC-AFM). However, the high contact resistance that originates from the metal-semiconductor Schottky contact disturbs the current flow and makes it difficult to measure the photoinduced current. To solve this problem, a thin metallic film has been coated on the surface of the device, which successfully decreases the contact resistance. In the PC-AFM analysis, we used a metal-coated conducting cantilever tip as the top electrode of the solar cell and light from a halogen lamp was irradiated on the PC-AFM scanning region. As the light intensity becomes stronger, the current value increases up to $200{\mu}A$ at 80 W, as more electrons and hole carriers are generated because of the photovoltaic effect. The ratio of the conducting area at different conditions was calculated, and it showed a behavior similar to that generated by a photoinduced current. On analyzing the PC-AFM measurement results, we have verified the correlation between the light intensity and photoinduced current of the poly-Si-based solar cell in nanometer scale.

• Journal of the Korean Society of Safety
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• v.33 no.6
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• pp.22-27
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• 2018

Fire fighters are exposed to the risk of many accidents during fire suppression, especially near the high voltage circuit. In order to prevent and analyze the electric shock accidents, measurement of water resistance is crucial. However, this has been one of the overlooked research areas and it has been very difficult to measure the mixed up resistance components separately. In this paper, we measured a total resistance of apparatus and regarded it as a serial resistance of contact resistance and length dependant resistance. Measuring the resistance by varying the length of water stream, the variable resistance and fixed contact resistance appear, which are used to calculate the both components of resistances. In addition, the resistance of fire hose can be calculated from the parallel circuit which is formed by grounding the fire hose with the resistance of water stream. Results show that we can successfully measure the resistance per unit length of water stream and fire hose, thereby proving that this method is a facile way to measure water and fire hose resistance. However, many experiments are still required to obtain the precise contact resistance of ground under various condition and the resistance between the human body and fire hose.

• Proceedings of the KSR Conference
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• 2006.11b
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• pp.742-747
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• 2006

This paper describes online stator-resistance estimation of a linear induction motor(LIM) with cage-type secondary using direct thrust control(DTC), where the resistance value is derived from stator-winding temperature estimation using thermocouple. In this paper, corrected stator resistance has an error in actuality measurement resistance. So compensation coefficient $\kappa$ which is decided through comparison and verifying several times relation of calculated resistance and measured motor line-line resistance. The stator-winding temperature information can also be used for monitoring, protection, and fault-tolerant control of the machine. Also, this paper reports the LIM's responses of the flux measured by the proposed stator resistance compensation algorithm.

• Nuclear Engineering and Technology
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• v.55 no.12
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• pp.4317-4328
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• 2023

To ensure the measuring accuracy of the wall temperature, the outer wall temperature measurement values by using three kinds of thermocouple welding methods were analyzed and evaluated in the paper, including single-point flush-mounted in the wall groove method, single-point insert-mounted in the wall groove, and outer surface direct welding method, based on the application of a tube-in-tube condensing heat exchanger. And the impacts of silver, tin, and thermal resistance adhesive as filling materials on wall temperature measurement were also investigated, and the results were compared to that obtained without filling materials. The results showed that the wall temperatures measured by the three welding methods were lower than the theoretically calculated value. And the wall temperature measured by the outer surface direct welding method was lowest under the same experimental conditions. The wall temperatures measured by single-point flush-mounted and insert-mounted in the wall groove methods were also affected by different welding filling materials. It was found that the greater the thermal resistance of filling materials, the smaller the heat loss. By analyzing the reasons for the low measured value of wall temperature, a new wall temperature measurement method was developed to improve the accuracy of the current measurement method. Meanwhile, the outer wall temperature measurement experiments of vertical and horizontal heat transfer tubes were carried out to validate and calibrate the improved outer wall temperature measurement method. The results showed that the average outer wall temperature deviation measured by the improved wall temperature measurement method ranged from - 0.82% to +2.29% for vertical tubes and - 4.75% to - 1.44% for horizontal tubes, and the improved measurement method had good measurement accuracy.

• Tuberculosis and Respiratory Diseases
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• v.40 no.3
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• pp.267-273
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• 1993

Background: Panting method for airway resistance measurement has the disadvantages of departing from the normal breathing pattern and of difficult for some patients to perform. We can measure airway resistance during quiet breathing under more physiologic conditions. Airway resistance is often measured during panting but attempts have been made to facilitate resistance measurements during quiet breathing. This study was designed to compare airway resistance measurements during panting with those during quiet breathing. Method: The 24 normal persons and 29 pulmonary disease patients were included in this study. Spirometry was performed and airway resistance measurement was also done during panting and quiet breathing concomittently. Results: The results were as follows; 1) High correlations were found between airway resistance measurements during panting and quiet breathing. 2) Resistance fell during panting, 21.2% in Raw tot, and 22.1% in Raw 0.5. 3) In normal persons, airway resistance fell more during panting when comparing to those in pulmonary disease patients. 4) This was largely independent of thoracic gas volume differences, because the specific airway conductance rose significantly during panting 5) The patients in whom resistance didn't fell during panting was supposed to the patients who couldn't perform panting successively because of high resistance. Conclusions: Although airway resistance can be measured during panting or quiet breathing according to the patient's performance, we must consider resistance fell during panting, by a mean 20%. It may be concluded that quiet breathing is more likely than panting to provide a relevant measurement of airway resistance.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.8 no.5
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• pp.354-358
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• 2015

The results of between resistance and optical transparency measurement in DOT-3 brake fluid contaminated moisture and particles generated from fraction of brake system was compared. Conventional resistance measurement method was known to be effaced by it's hygroscopic characteristics. However, the particle is a significant element of the contamination sources. Proposed optical transparency measurement is linear and effective than that of contamination in brake fluid.

• Proceedings of the KIEE Conference
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• 1998.07b
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• pp.766-768
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• 1998

Optical Temperature Distribution measurement System (OTDS) is completely different from conventional electric point sensor in that it uses the optical fiber itself as the sensor. This new concept in temperature measuring system requires only one fiber to be laid. The use of optical fiber also gives the advantage of small diameter, light weight, explosion resistance, and electromagnetic noise resistance. The OTDS is a sensor which is capable of making a precise measurement over a wide range of areas using only a single optical fiber. Since current temperature sensors, such as the thermocouple, are only used to measure temperaturea of point, they are almost impractical for measuring a wider range because of the extremely high cost. In comparision with current sensors, the optical fiber distributed temperature sensor can make much quicker and more precise measurements at a comparatively low cost.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1998.06a
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• pp.87-91
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• 1998

In this paper, We analyzed the current-voltage characteristics with n-type silicon substrates concentration and temperature variations (Room temperature, 50$^{\circ}C$, 75$^{\circ}C$) in platinum silicide and silicon junction. The electrical parameters of measurement are turn-on voltage, saturation current, ideality factor, barrier height, dynamic resistance in forward bias and reverse breakdown voltage according to variations of junction concentration of substrates and measurement temperature variations. As a result, the forward turn-on voltage, reverse breakdown voltage, barrier height and dynamic resistance were decreased but saturation currents and ideality factor were increased by substrates increased concentration variations in platinum silicide and n-silicon junction. In increased measurement temperature (RT, 50$^{\circ}C$, 75$^{\circ}C$), the extracted electrical parameter values of characteristics were rises by increased temperature variations according to the forward and reverse bias.