• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.533-536
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• 1998

The electrical characteristics of NMOSFETs with asymmetrical source/drain regions have been expermentally investigated using test devices fabricated by $0.35\mu\textrm{m}$ CMOS technology. The performance degradation for asymmetric transistor and its causes are analyzed. The parasitic resistances, such as series resistance of active regions and silicide junction contact resistance, are distributed in parallel along the channel. Depending on source/drain geometry, the array of those resistances is changed, that results the various electrical properties.

• Proceedings of the IEEK Conference
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• 2002.07b
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• pp.1346-1349
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• 2002

This paper presents the design and implementation of 16-QAM modem that can be applied to fixed broadband wireless access systenm. It is implemented in the hardware prototype that consist of FPGA(Field Programmable Gate Array) for digital signal processing and analog front end module for analog signal processing. We provide 20.48Mbps data rate using implemented modem and test the modem in KOREA 26㎓ broadband wireless local loop system including IFU(Intermediate Frequency Unit) and RFU(Radio Frequency Unit) via air interface.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.05a
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• pp.984-984
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• 2001

위성체의 태양전지판과 안테나와 같은 구조물은 발사시 체적을 최소화하기 위하여 설정궤도에 도달하기 전까지 접혀진 상태로 운반되며, 설정궤도에 도달 후 고유의 임무를 수행하기 위하여 안테나, 태양전지판 및 로보트 팔과 같은 이차 부착물의 전개 작업을 수행한다. 이러한 작업은 위성체 및 발사체의 고유임무를 수행하는데 매우 중요한 작업이며, 이 작업의 성공 유무가 우주비행체 임무의 성패를 좌우한다.

• Proceedings of the IEEK Conference
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• 1999.11a
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• pp.139-142
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• 1999

In this paper, a method of Radome design is considered. The shape is similar to tangent-ogive, and the antenna is a waveguide broad-wall slot array antenna. The characteristic of the Radome material is obtained by measuring test samples. By analyzing the transmission efficiency of the flat plate, Radome wall thickness is determined firstly. And then, the detailed characteristics of the Radome are analyzed by using GO-PO approximation technique. Several simple parameters of the designed Radome are tested and compared with the simulation results.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2011.10a
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• pp.705-706
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• 2011

• Proceedings of the Optical Society of Korea Conference
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• 2006.02a
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• pp.371-372
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• 2006

A 10Mbps optical wireless link using LED array has been demonstrated. The modulation bandwidth of the LED has been measured, and the transmission test according to modulation frequency has been also carried out. The good communication performance has been obtained at about 30cm distance at 10Mbps data rate.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.806-809
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• 2007

SRAM cell array and peripheral circuits on display panel are designed using LTPS process. To overcome low yield of SOP, high speed parallel fault detection circuitry for memory cells is designed at local I/O lines with minimal overhead for efficient memory cell redundancy replacement. Normal read/write and parallel test read/write are simulated and verified.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.2
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• pp.341-345
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• 2006

The GPS is widely used in various parts, therefore it is required higher integrity and continuity. These integrity and continuity are threatened by outer jamming signals which are intended or not. And various anti-jamming ways have been studied to remove these jamming signals. In this paper, we are going to test the efficiency of the anti-jamming algorithm in space and time-space domain, and analyze

• Journal of Power Electronics
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• v.5 no.4
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• pp.257-263
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• 2005

This paper describes the development and testing results of a high density High Voltage Power Supply (HVPS) that drives microwave Traveling Wave Tubes (TWTs) of phased array transmitters for airborne EW systems. The HVPS is designed to consist of a number of modules connected in series. Among them, especially, the high-density pulse transformer module including the resonant circuit is newly designed to make the HVPS much more reliable. In addition, this paper describes the development of high voltage solid-state modulation using fast switching devices (FETs) and also represents the test results of a modulator module.

• Journal of the Korean Society for Nondestructive Testing
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• v.36 no.4
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• pp.288-294
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• 2016

This paper aims to compare the ability to detect notch defects existing in the plate and welded area using a flexible ECA (eddy current array) probe with OmniScan MX and MS-5800E. The characteristics of signals with various frequencies and lift-offs were also compared. As a result, when signals of frequencies 500, 1000, and 1500 kHz were used, the amplitude of the signal increased, as the depth of the notch increased, but reduced linearly in accordance with the lift-off variation. In addition, the detection sensitivity of the weld defect was found to be closely related to the contact surface of the probe and specimen. In this paper, it was demonstrated that the detection sensitivity was excellent when the contact surface of the probe and the specimen was sufficient, but it was poor when the contact surface was insufficient.