• Journal of the Korean Society of Costume
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• v.53 no.5
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• pp.1-12
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• 2003

This paper proposes a system for measuring the 3D human bodies using the multiple 2D images. The system establishes the multiple image input circumstance from the digital camera for image measurement. The algorithm considering perspective projection leads us to estimate the 3D human bodies from the multiple 2D images such as frontal. side and rear views. The results of the image measurement is compared those of the direct measurement and the 3D scanner for the total 40 items (12 heights, 15 widths and 13 depths). Three persons measure the 40 items using the three measurement methods. In comparison of the results obtained among the measurement methods and the persons, the results between the image measurement and the 3D scanner are very similar. However, the errors for the direct measurement are relatively larger than those between the image measurement and the 3D scanner. For example, the maximum errors between the image measurement and the 3D scanner are 0.41cm in height, 0.39cm in width and 0.95cm in depth. The errors are acceptable in body measurement. Performance of the image measurement is superior to the direct. because the algorithm estimates the 3D positions using the perspective projection. In above comparison, the image measurement is expected as a new method for measuring the 3D body, since it has the various advantages of the direct measurement and 3D scanner in performance for measurement as well as in the devices, cost, Portability and man power.

• Journal of electromagnetic engineering and science
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• v.9 no.1
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• pp.7-11
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• 2009

An Ultra-WideBand(UWB) Low-Noise Amplifier(LNA) is proposed and is implemented in a $0.18-{\mu}m$ CMOS technology. The proposed UWB LNA provides excellent wideband characteristics by combining a High-Pass Filter (HPF) with a conventional resistive-loaded LNA topology. In the proposed UWB LNA, the bell-shaped gain curve of the overall amplifier is much less dependent on the frequency response of the HPF embedded in the input stage. In addition, the adoption of fewer on-chip inductors in the input matching network permits a lower noise figure and a smaller chip area. Measurement results show a power gain of + 10 dB and an input return loss of more than - 9 dB over 2.7 to 6.2 GHz, a noise figure of 3.1 dB at 3.6 GHz and 7.8 dB at 6.2 GHz, an input PldB of - 12 dBm, and an IIP3 of - 0.2 dBm, while dissipating only 4.6 mA from a 1.8-V supply.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.04a
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• pp.998-1002
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• 1997

This study has been performed to predict beam absorption with analysis of temperature field by using a FEM in co /sab 2/ laser hardening and to invesrigate into some effects of power density and travel speed of laser beam on the microstructure and hardness of ductile cast iron treated by laser surface hardening technique. Optical micrograph has shown that large martensite and small amount of retained austenite appear in inside hardened zone. Hardness measurement has revealed that the range of maximum hardness value is Hv=415 .+-. 10. The power density increases and the travel speed decreases, the depth of hardened zone increases due to increase of input power density.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.3
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• pp.228-233
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• 2001

This paper presents the optimized design, fabrication and thermal characteristics of micro-heaters for thermal MEMS (micro elelctro mechanical system) applications usign SOI (Si-on-insulator) and trench structures. The micro-heater is based on a thermal measurement principle and contains for thermal isolation regions a 10㎛ thick Si membrane with oxide-filled trenches in the SOI membrane rim. The micro-heater was fabricated with Pt-RTD (resistance thermometer device) on the same substrate by suing MgO as medium layer. The thermal characteristics of the micro-heater wit the SOI membrane is 280$\^{C}$ at input power 0.9W; for the SOI membrane with 10 trenches, it is 580$\^{C}$ due to reduction of the external thermal loss. Therefore, the micro-heater with trenches in SOI membrane rim provides a powerful and versatile alternative technology for improving the performance of micro-thermal sensors and actuators.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.29 no.3 s.234
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• pp.409-416
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• 2005

We need to develop a on-line thermal performance analysis system for nuclear power plant to determine performance status and heat rate of turbine cycle. We have developed PERUPS(PERformance Upgrade System) to aid the effective performance analysis of turbine cycle. Procedures of performance calculation are improved using several adaptations from standard calculation algorithms based on PTC(Performance Test Code). Robustness in the on-line performance analysis is increased by verification & validation scheme for measured input data. The system also provides useful web interfaces for performance analysis such as graphic heat balance of turbine cycle and components, turbine expansion lines, automatic generation of analysis report. The system was successfully applied for YongGwang nuclear plant unit #3,4.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.569-572
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• 2000

This paper presents the optimized fabrication and thermal characteristics of micro-heaters for thermal MEMS applications using a SDB SOI substrate. The micro-heater is based on a thermal measurement principle and contains for thermal isolation regions a 10$\mu\textrm{m}$ thick silicon membrane with oxide-filled trenches in the SOI membrane rim. The micro-heater was fabricated with Pt-RTD(Resistance Thermometer Device)on the same substrate by using MgO as medium layer. The thermal characteristics of the micro-heater with the SOI membrane is 280$^{\circ}C$ at input Power 0.9 W; for the SOI membrane with 10 trenches, it is 580$^{\circ}C$ due to reduction of the external thermal loss. Therefore, the micro-heater with trenches in SOI membrane rim provides a powerful and versatile alternative technology for improving the performance of micro thermal sensors and actuators.

• ETRI Journal
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• v.45 no.2
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• pp.338-345
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• 2023

A filtering power divider based on air-filled substrate-integrated waveguide (AFSIW) technology is proposed in this study. The AFSIW structure is used in the proposed filtering power divider for substantially reducing the transmission losses. This structure occupies a large area because of the use of air as a dielectric instead of typical dielectric materials. A filtering power divider provides power division and frequency selectivity simultaneously in a single device. The proposed filtering power divider comprises three AFSIW cavities. The filtering function is achieved using symmetrical inductive posts. The input and output ports of the proposed circuit are realized by directly connecting coaxial lines to the AFSIW cavities. This transition from the coaxial line to the AFSIW cavity eliminates the additional transitions, such as AFSIW-SIW and SIW-conductor-backed coplanar waveguide, applied in existing AFSIW circuits. The proposed power divider with a second-order bandpass filtering response is fabricated and measured at 5.5 GHz. The measurement results show that this circuit has a minimum insertion loss of 1 dB, 3-dB fractional bandwidth of 11.2%, and return loss exceeding 11 dB.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.27 no.1
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• pp.84-87
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• 2016

In this paper, a receiver for wireless power transfer is proposed. The receiver consists of a 100 W rectifier in 1.8 MHz frequency band, and a constant current charger. In particular, two kinds of protection circuits are installed in the rectifier. They are a over-voltage protection circuit which block the input voltages greater than 30 V and a active-dummy load which maintains the receiver input impedance by automatically consuming the remaining input power. The constant current charger is designed to charge the battery with a charging current of up to 1 A. A wireless charging system is fabricated using the proposed receiver. The system is composed of a 130 W transmitter, two magnetic resonator, and proposed receiver for charging a 48 V Li-Ion battery using the coupled magnetic resonance method. By the measurement result, the system efficiency is about 54 %.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.8 no.4
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• pp.38-44
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• 1999

This paper primarily directed toward analyzing the frequency response in hydraulic pipe lines with a small diameter. The exact solution to the frequency response is obtained by using the complicated transfer function. The discrepancy with the exact and the approximate is small so the approximation solution is adopted to compare the experimental results with the theoretical analysis. In this experiment the input frequency was generated by the frequency generator with the ball valve and speed controller. In order to compare the theoretical were forms with the experimental ones the trace obtained from the oscilloscope is photographed, The diameter the length of lines and input pressure amplitude are varied to investigate their effects,. the experiment results show that th values of dimensionless parameter are very affected to the phase delay and guide response time in the design of pressure manifold to measure the pressure of hydraulic pipelines.

• ETRI Journal
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• v.17 no.2
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• pp.11-19
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• 1995

The plasma densities generated from a semiconductor bridge (SCB) device employing a capacitor discharge firing set have been measured by a novel diagnostic technique employing a microwave resonator probe. The spatial resolution of the probe is comparable to the separation between the two wires of the transmission lines (${\approx}$3 mm). This method is superior to Langmuir probes in this application because Langmuir probe measurements are affected by sheath effects, small bridge area, and unknown fraction of multiple ions. Measured electron densities are related to the land material and input energy. Although electron densities in the plasma generated by aluminum or tungsten-land SCB devices show a general tendency to increase steadily with power, at the higher energies, the electron densities generated from tungsten-land SCB devices are found to remain constant.