• Journal of Korea Game Society
• /
• v.5 no.1
• /
• pp.11-18
• /
• 2005

Recently, as one method of the game manipulation, physical interactive game is increasing, which controls the program by direct human movement. Tangible interface for physical interactive game implementation can control virtual model directly through real world object. A digital desk, one of the tangible interface, offers the interface that human can manipulate virtual object directly, by making projection screen on real world desk as computer display device. In this paper, we implement "Battle Region" game in the form of tangible interface, which can offer game users an efficient and amusing experiences by the use of physical interactive game. Traditional game cannot pursuit the diversity of game background contents but our game can do it through Map image projection. From this, game provider can supply the diversity of choice and users ran set up the difficulty of game. Therefore, our implemented game can offer users an efficient and amusing experiences by making game user's challenge and satisfaction maximum.

• Journal of the Korean Institute of Telematics and Electronics T
• /
• v.35T no.3
• /
• pp.128-133
• /
• 1998

This paper is study on performance analysis of modulator using direct digital frequency synthesizer of Initial Clock Accumulating Method. It has been generally used for PLL or digital frequency synthesizing method to be synthesizd randomly chosen frequency state. In order to improve disadvantage of two methods, we constructed modulator system using DDFS of Initial Clock Accumulating Method. We also confirmed the coherence frequency hopping state and possibility of phase control. The results obtained from the experiments are as follows; First, the synthesized output frequency is proportional to the sampling frequency, according to index, K. Second, the difference of the gain between the basic frequency and the harmonic frequencies was more than 50 [dB], that is, this means facts that is reduced the harmonic frequency factor. Third, coherence frequency hopping state is confirmed by PN code sequence. Here, we confirmed the proposed method cut switching time, this verify facts that is the best characteristic of the frequency hopping. We also verified the fact that the phase varies as the adder is operated set or reset.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2008.05a
• /
• pp.841-844
• /
• 2008

This paper describes technical method about remote control and monitoring of local system by use internet web connection system, which connect local system and system manager works in long distance office. The local system, which will be controlled remotely have constructed with analog/digital signal acquisition device, signal control board and their software. The local systems are constructed with several electronic modules need AC or DC power supply to operate the right way. We used NI labview software to control and monitoring of local system. The computer server for remote connection are constructed with Apache web server, PHP and MySQL ODBC. The experiment for the remote control are need internet web browser which load local control software. By use of web system, we have experimented control and monitoring of local electronic module.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.42 no.9
• /
• pp.789-794
• /
• 2014

The FPGA is used to the high speed digital satellite communication on the Digital Signal Process Unit of the next generation GEO communication satellite. The high capacity FPGA has the high power dissipation and it is difficult to satisfy the derating requirement of temperature. This matter is the major factor to degrade the equipment life and reliability. The thermal control at the equipment level has been worked through thermal conduction in the space environment. The FPGA of CCGA or BGA package type was mounted on printed circuit board, but the PCB has low efficient to the thermal control. For the FPGA heat dissipation, the heat sink was applied between part lid and housing of equipment and the performance of heat sink was confirmed via thermal vacuum test under the condition of space qualification level. The FPGA of high power dissipation has been difficult to apply for space application, but FPGA with heat sink could be used to space application with the derating temperature margin.

• Proceedings of the KIEE Conference
• /
• 2005.04a
• /
• pp.210-212
• /
• 2005

최근 급속도로 발전하고 있는 산업분야에서 요구되는 서보 시스템에서 빠른 응답특성, 고도의 정밀성 그리고 안전성에 대한 요구가 커지고 있는 실정이다. 본 논문에서는 이러한 요구에 따라 5상 IPM(Five-phase IPM)의 DTC(Direct torque control)에 대해 고찰하였으며, Texas Instruments사에서 전동기 제어 전용으로 개발된 DSP칩인 TMS320F2812를 이용하여 디지털적으로 제어 알고리즘을 구성하였다. 5상 전동기는 현재 산업현장에서 일반적으로 널리 사용되고 있는 삼상 전동기에 비해 안정성이 높고, 상당 전압의 변화 없이 고정자 전류를 줄일 수 있고, 토크 맥동의 주파수를 높이고 결과적으로 토크의 크기를 감소시킬 수 있다는 여러 가지 장점을 가지고 있으며, 특히 안정성을 요구하는 항공기(Aerospace applications), 전기자동차 및 하이브리드 자동차(Electric or hybrid vehicles)등의 특수한 영역에서 요구가 계속 증가되고 있다. 따라서 본 논문에서는 5상 IPM의 DTC에 대한 특성을 실험을 통하여 확인하였다.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.14 no.3
• /
• pp.285-289
• /
• 2004

Recently, due to the high development of the internet, needs for multimedia streams such as digital audio and video is increasing much more. In case of transmitting multimedia streams using the User Datagram Protocol (UDP), it may cause starvation of TCP traffic on the same transmission path, thus resulting in congestion collapse and enormous delay because UDP does not perform TCP-like congestion control. Because of this problem, diverse researches are being conducted on new transmission schemes and protocols intended to efficiently reduce the transmission delay of real-time multimedia streams and perform congestion control. The TCP-friendly congestion control schemes can be classified into the window-based congestion control, which uses the general congestion window management function, and the rate-based congestion control, which dynamically adjusts transmission rate by using TCP modeling equations and the like. In this paper, we suggest the square-root congestion avoidance algorithm with the hybrid TCP-friendly congestion control scheme which the window-based and rate-based congestion controls are dealt with in a combined way. We apply the proposed algorithm to the existing TEAR. We simulate the performance of the proposed TEAR by using NS, and the result shows that it gives better improvement in the stability needed for providing congestion control than the existing TEAR.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2008.10a
• /
• pp.797-801
• /
• 2008

This paper describes technical method about remote control and monitoring of local system by use personal mobile device in anytime and anywhere. Therefore, the user don't need to stay in operation room of local system. The PC server environment for the mobile connection are constructed with Apache web server, PHP and MySQL ODBC. The mobile internet homepage for the remote mobile connection is designed by Anybuilder software and mobile simulator, Openwave SDK 6.2 is used for the development. The mobile internet program can be applicate to all of domestic communication companies LGT, SKT and KTF. We use KTF mobile contains WAP browser for the test. We used NI Labview software to control and monitoring of local system. The local system, which will be controlled remotely have constructed with analog/digital signal acquisition device, signal control board and their software. By experiments, we confirmed remote control by mobile device are possible.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.8 no.2
• /
• pp.304-309
• /
• 2004

Recently, the needs for multimedia stream such as digital audio and video in the Internet has increased tremendously. Unlike TCP, the UDP protocol, which has been used to transmit streaming traffic thorough the Internet, does not apply any congestion control mechanism to regulate the data flow thorough the shared network And it leads to congestion collapse of the Internet and results in long-term transmission delay. To avoid any adverse effect on the current Internet functionality, a now protocol of modification or addition of some functionality to perform congestion control and to reduce huge transmission delay in transmitting of multimedia stream are in study. TCP-friendly congestion control mechanism is classified into two : one is window-based congestion control scheme using general window management functionalities, the other is rate-based congestion control scheme using TCP modeling equation. In this paper, we propose an algorithm for improving the transmitting rate on a hybrid TCP-friendly congestion control scheme combined with widow-based and late-based congestion control for multimedia stream. And we also simulate the performance of improved TEAR implementation using NS. With He simulation results, we show that the improved TEAR can provide better fairness and lower rate fluctuations than TCP.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.17 no.5
• /
• pp.141-148
• /
• 2003

In the recently, the necessity of the hybrid type linear stepping motor(HLSM) of linear motion digital actuator has been increased in the various fields of the automatic control system. The HLSM is directly performed without any converting mechanism. Therefore, the HLSM is better advantaged in the efficiency and economical view than a rotary stepping motor. In this paper, we have designed an optimum tooth shape by the 2D finite element method(FEM) to develop the HLSM with longitudinal flux machine(LFM) type, and calculated the thrust force and normal force. And we have manufactured the prototype of it, and have experimented the thrust force characteristics of it.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2003.10a
• /
• pp.837-840
• /
• 2003

Recently the multimedia streaming traffic such as digital audio and video in the Internet has increased tremendously. Unlike TCP, the UDP protocol, which has been used to transmit streaming traffic through the Internet, does not apply any congestion control mechanism to regulate the data flow through the shared network. If this trend is let go unchecked, these traffic will effect the performance of TCP, which is used to transport data traffic, and may lead to congestion collapse of the Internet. To avoid any adverse effort on the current Internet functionality, A study on a new protocol of modification or addition of some functionality to existing transport protocol for transmitting streaming traffic in the Internet is needed. TCP-frienly congestion control mechanism is classified with window-based congestion control scheme and rate-based congestion control scheme. In this paper, we propose an algorithm for improving the transmitting rate on a hybrid TCP-friendly congestion control scheme combined with widow-based and rate-based congestion control for multimedia streaming in the internet.