• Proceedings of the KIEE Conference
• /
• 2005.10a
• /
• pp.122-127
• /
• 2005

This paper proposes a prototype IED hardware design and it's real-time experimental results. To evaluate performance of the IED, the study is well constructed power system model including power transformer utilizing the EMTP software and the testing is made through simulation of various cases. The relaying that is well constructed using DSP chip and RISC CPU etc. has been developed and the prototype IED has been verified through on-line testing by LabVIEW simulator. The results show that an advanced relaying based prototype IED never mis-operated.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2007.04a
• /
• pp.128-134
• /
• 2007

Combustion performance and characteristics of high-pressure subscale liquid rocket combustors were studied experimentally. Four different models of combustor were considered in this paper. The high-pressure subscale combustor is composed of the mixing head, the water cooling cylinder and the nozzle. One model of the combustors employed regenerative cooling combustor in that the kerosene used for the chamber cooling is burned. This combustor was damaged due to a high frequency combustion instability occurred during a firing test. The results of the firing tests, comparison of performance, and characteristics of static and dynamic pressures of the combustors are described.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2003.05a
• /
• pp.317-319
• /
• 2003

HILS(Hardware In-the Loop Simulation) is commonly used in the development and testing of embedded systems, when those systems cannot be tested easily, thoroughly, and repeated in their operational environments. HILS can be a useful tool to develop products more quickly and cost effectively and also reduces the possibility of serious defects being discovered after production. During the product development period, Design optimization and hardware/software debugging can be performed using HILS skill. This paper describes a HILS model for the STG(Steam-Turbine Generator) Simulator to prove the performance of the developed Digital Governor. It is developed using software technics which can confirm the responses of a real-time system.

• Journal of Broadcast Engineering
• /
• v.2 no.1
• /
• pp.24-35
• /
• 1997

Basic and transmission video quality testing was performed in real-time mode using hardware video codec based on MPEG-2 MP@ML standard including subsequent transmitting and receiving satellite simulator unit. The double-stimulus Impairment scale method and the double-stimulus continous quality scale method based on CCIR 500-5 were used as an evaluation method. The whole digital broadcasting satellite system consisting of MPEG-2 codec, system mux/demux, channel codec, channel, modem, antenna, etc. was put into the overall video quality testbed and the basic and transmission error quality assessment was performed at various bitrates and BER for an integrated system performance evaluation. In transmission error video quality testing, transmission error video quality maintained on average above 3.9 point on the 5-point scale. The low-bit rate quality such as film mode(@2Mbps) highly depended on the statitical characteristics of video source and maintained on average around 2.7 point.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.46 no.12
• /
• pp.1012-1020
• /
• 2018

In order to improve the capability of mission flight of tiltrotor UAV that has been developed by Korea Aerospace Research Institute, a simulation study on the formation flight of autonomous control 5 level has been performed. The formation flight is based on the centralized method with leader and follower airplanes. The formation flight controller was verified through numerical simulation with 3 followers and hardware-in-the loop simulation with 1 follower. This paper describes controller design methods, hardware-in-the-looped simulation test, and performance verification using simulation.

• The KIPS Transactions:PartA
• /
• v.11A no.3
• /
• pp.109-114
• /
• 2004

Increasing popularity of WLAN and advancement of WPAN allow user to connect to the Internet easily today. The increasing of number of networking mobile device such as laptop and PDA requires computing devices to share high speed Internet line or work on networks in most cases. This has stimulated the demand of access point that supports multiple network interfaces. This paper describes the process of design, implementation and test of the wired/wireless integrated access point that supports multiple network interfaces such as wired LAN, wireless LAN, Bluetooth, and Broadband network. We designed and developed the hardware system and protocol software to integrate heterogeneous network. The system has shown compatibility with standard specification and good performance through testing with various network devices.

• Journal of Energy Engineering
• /
• v.7 no.1
• /
• pp.96-102
• /
• 1998

The use of computers as part of nuclear safety systems elicits additional requirements-software verification and validation (v/v), hardware qualification-not specifically addressed in general industry fields. The computer used in nuclear power plants is a system that includes computer hardware, software, firmware, and interfaces. To develop the computer systems graded with nuclear safety class, the developing environments have to be required in advance and the developed software have to be verified and validated in accordance with nuclear code and standards. With this requirements, the test facility for Inadequate Core Cooling Monitoring System (ICCMS) as one of safety systems in the nuclear power plants was developed. The test facility consists of three(3) parts such as Input/Output (I/O) simulator, Plant Data Acqusition System (PDAS) cabinets and supervisory computer. The performance of the system was validated by manual test procedure.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.19 no.6
• /
• pp.666-673
• /
• 2013

This paper proposes the performance evaluation test of attitude heading reference system (AHRS) suitable for small high speed autonomous underwater vehicle(AUV). Although IMU can provides the detail attitude information, it is sometime not suitable for small AUV with short operation time in view of price and the electrical power consumption. One of alternative for tactical grade IMU is the AHRS based micro-machined electro mechanical system(MEMS) which can overcome many problems that have inhibited the adoption of inertial system for small AUV such as cost and power consumption. A cost effective and small size AHRS which incorporates measurements from 3-axis MEMS gyroscopes, accelerometers, and 3-axis magnetometers has been developed to provide a complete attitude solution for AUV and the attitude calculation algorithm is derived based the coordinate transform equation and Kalman filter. The developed AHRS was validated through various performance tests as like the magnetometer calibration, operating experiments using land mobile vehicle and flight motion simulator (FMS). The test of magnetometer calibration shows the developed MEMS AHRS is robust to the external magent field change and the test with land vehicle proves the leveling error of developed MEMS AHRS is below $0.5^{\circ}/hr$. The results of FMS test shows the fact that AHRS provides the measurement with $0.5^{\circ}/hr$ error during 5 minutes operation time. These results of performance evaluation tests showed that the developed AHRS provides attitude information which error of roll and pitch are below $1^{\circ}$ and the error of yaw is below $5^{\circ}$ and satisfies the required specification. It is expected that developed AHRS can provide the precise attitude measurement under sea trial with real AUV.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.33 no.3
• /
• pp.86-92
• /
• 2005

Synthetic Aperture Radar is an active sensor utilizing the microwaves in order to get the requested high resolution imageries day or night regardless of the weather conditions. In this paper, the architecture of a real-time system controller for the airborne small SAR system, KOrea Miniature SAR which was developed by Agency for Defense Development is proposed considering the embedded real-time environment. The main purpose of the system controller is to control the internal and the rest of subsystem within SAR system in real-time. The main characteristics of the proposed system controller were implemented using the real-time operating system and the distributed hardware architecture for the small, low weight and real-time operation. The system controller performance and real-time operation were verified and confirmed by the demo flight with the KT-1 airplane.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.49 no.6
• /
• pp.481-488
• /
• 2021

The satellite telecommand processing system is the only way to provide telecommands for status monitoring, control, and mission execution. Domestic satellites can be divided into science, technology, and multi-purpose satellites, and geostationary satellites. These Satellites uses CCSDS standard protocol to communicate with ground stations. However, existing domestic satellites use only software to decode telecommands which increases cost of software development and verification of the developed software. Performance of software only approach is relatively low compared to hardware. In this paper, we present ASIC processing system specifically designed to decode telecommands. The system consists of a telecommand RAM, a protocol RAM/ROM, an ASIC, an interface unit of FPGA, and a relay block. The system handles general commands and pulse commands that are used in satellites. We established a ground station equipment and test environment to verify the system functionality, The result shows that our system reduces the development cost by 1/5 and improves the performance by 10⁵ times compared to the previous systems that decode telecommands only by software.