• 한국정보통신설비학회:학술대회논문집
• /
• 2008.08a
• /
• pp.414-417
• /
• 2008

This paper presents the design and analysis of 2.45GHz Low-IF Mixer using CMOS 0.18um. The Mixer is implemented by using the Gilbert-type configuration, current bleeding technique, and the resonating technique for the tail capacitance. And the design of this Double Balance Mixer is based on its lineaity since it is important in the interference cancellation system. The low flicker noise mixer is implemented by incorporating a double balanced Gilber-type configuration, the RF leakage-less current bleeding technique, and Cp resonating technique. The proposed mixer has a simulated conversion gain of 16dB a simulated IIP3 of -3.3dBm and P1dB is -19dBm. A simulated noise figure of 6.9dB at l0MHz and a flicker corner frequency of 510kHz while consuming only 10.65mW od DC power. The layout of Mixer for one-chip design in a 0.18-um TSMC process has 0.474mm$\times$0.39 mm size.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2003.05a
• /
• pp.594-597
• /
• 2003

To link direct load control and economic operation considering system spinning reserve characteristics, this paper presents a new metholodogy. By formulating new constraints, considering system spinning reserve characteristics is possible. And by employing 3-D dynamic programming, linking direct load control and economic operation is possible. As a result, economical DLC and operation schedule of the power system is possible. The usefulness of the method is verified by applying to the test system.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2003.06a
• /
• pp.670-673
• /
• 2003

Fabrication of three dimensional microstructures by laser-assisted chemical vapor deposition of material is investigated. To fabricate microstructures, a thin layer of deposit in desired patterns is first written using laser direct writing technique and on top of this layer a second layer is deposited to provide the third dimension normal to the surface. By depositing many layers. a three dimensional microstructure is fabricated. Optimum deposition conditions for direct writing of initial and subsequent layers with good surface quality and profile uniformity are determined. Using an arson ion laser and ethylene as the light source and reaction gas, respectively, fabrication of three-dimensional carbon microstructures is demonstrated.

• Proceedings of the Korea Multimedia Society Conference
• /
• 2001.11a
• /
• pp.558-562
• /
• 2001

오늘날 월드 와이드 웹(WWW)의 성장과 함께 인터넷 상에서 3차원 세계를 표현해야 할 필요성이 급격히 증가하고 있다. 이러한 요구에 부응하여 VRML97이 개발되었고, 이는 인터넷에서 3차원 그래픽스 데이터의 표준으로 중요한 역할을 해왔다. 그리고 현재 VRML97로 기술된 데이터를 위한 브라우저가 많이 개발되어 왔다. 현재까지는 대부분 OpenGL이나 Direct3D와 같은 API를 주로 사용해왔으나 SUN의 Java3D가 활성화되면서 Java3D 기반의 VRML97 브라우저도 많이 개발되고 있다. 또한 SUN에서는 이미 3D 브라우저를 위한 프로토타입을 개발하여 제공하고 있다. 본 논문에서는 본 연구팀에서 수행하고 있는 서버-클라이언트 모델의 가상현실 시스템의 클라이언트로서의 X3D 브라우저 개발을 위한 기반 연구로서 수행된 Java3D 기반의 VRML97 브라우저의 이벤트 모델에 대하여 기술한다.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2013.07a
• /
• pp.45-46
• /
• 2013

대중에게 하나의 취미 생활로 자리매김한 게임은 특징이나 작동 방법에 따라 다양한 장르로 발전되었다. 그 중 액션게임 장르는 사용자가 조작하는 캐릭터의 역동적인 움직임과 움직임이 큰 동작으로 인해 사용자로 하여금 게임 플레이에 몰입할 수 있는 특징을 가지고 있다. 과거 2D 환경의 게임에서 연속되는 그림으로 표현되던 캐릭터의 애니메이션 장면은 3D 환경으로 발전하면서 새로운 애니메이션 기법을 필요로 하였으며, 현재 다양한 애니메이션 기법이 연구되고 있다. 본 논문에서는 3D 뼈대 애니메이션 통하여 DirectX에서의 캐릭터 애니메이션 적용 대해 설명한다.

• JSTS:Journal of Semiconductor Technology and Science
• /
• v.9 no.3
• /
• pp.153-159
• /
• 2009

A CMOS frequency synthesizer for $5{\sim}6$ GHz UNII-band sub-harmonic direct-conversion receiver has been developed. For quadrature down-conversion with sub-harmonic mixing, octa-phase local oscillator (LO) signals are generated by an integer-N type phase-locked loop (PLL) frequency synthesizer. The complex timing issue of feedback divider of the PLL with large division ratio is solved by using multimodulus prescaler. Phase noise of the local oscillator signal is improved by employing the ring-type LC-tank oscillator and switching its tail current source. Implemented in a $0.18{\mu}m$ CMOS technology, the phase noise of the LO signal is lower than -80 dBc/Hz and -113 dBc/Hz at 100 kHz and 1MHz offset, respect-tively. The measured reference spur is lower than -70 dBc and the power consumption is 40 m W from a 1.8 V supply voltage.

• Proceedings of the Korean Society For Composite Materials Conference
• /
• 2003.04a
• /
• pp.5-9
• /
• 2003

Stress and deflection of Active Fiber Composite(AFC) embedded and/or attached composite structures are numerically investigated at the constituent level by the Direct Numerical Simulation(DNS). The DNS approach which models and simulates the fiber and matrix directly using 3D finite elements need to be solved by efficient way. To handle this large scale problem, parallel program for solving piezoelectric behavior was developed and run on the parallel computing environment. Also, the stress result from DNS approach is compared with that from uniform field model.

• Journal of the Korea Society for Simulation
• /
• v.19 no.1
• /
• pp.63-71
• /
• 2010

In modern war, Intercept Performance of SAM(Surface to Air Missile) is gaining importance as range and precision of Missile and Guided Weapon on information warfare have been improved. An aerial defence system using Surface-to-air Radar and Guided Missile is needed to be built for prediction and defense from threatening aerial attack. When developing SAM, M&S is used to free from a time limit and a space restriction. M&S is widely applied to education, training, and design of newest Weapon System. This study was conducted to develop simulator for evaluation of Intercept Performance of SAM. In this study, architecture of Intercept Performance of SAM analysis simulator for estimation of Intercept Performance of various SAM was suggested and developed. The developed Intercept Performance of SAM analysis simulator was developed by C++ and Direct3D, and through 3D visualization using the Direct3D, it shows procedures of the simulation on a user animation window. Information about design and operation of Fighting model is entered through input window of the simulator, and simulation engine consisted of Object Manager, Operation Manager, and Integrated Manager conducts modeling and simulation automatically using the information, so the simulator gives user feedback in a short time.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.9 no.6
• /
• pp.1226-1233
• /
• 2005

The purpose of this paper is to overview the recently changed environments of developing a computer game software and propose an appropriate developemnt methodology to these environments. For the speed of playing 3-dimensional games in window-based environments of personal computer, we investigated DirectX as a game development library and suggested a guideline for developing 3-dimensional computer games which is compatible with various hardware platforms and keep up a fitting speed of game-playing.

• Proceedings of the IEEK Conference
• /
• 2003.07e
• /
• pp.2375-2378
• /
• 2003

In manufacture of printed circuit boards, one important issue is precisely to measure the three-dimensional shape of the solder paste silk-screened prior to direct surface mounting of chips. This paper presents the 3D shape reconstruction of solder paste using the optical triangulation method based on structured light or slit beam and the measurement algorithm for height, volume. area, and coplanarity on component pads from the 3D range image. Futhermore, statistical process control function is incorporated for process capability analysis.