• Aerospace Engineering and Technology
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• v.13 no.1
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• pp.55-62
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• 2014

FTSR(Flight Termination System Receiver) is a device that receives a ground command signal to abort a flight mission when abnormal conditions occur in the space launch vehicle. The secure tone command message shall consist of a series of 11 character tone pattern. Each character consists of the sum of two tones which taken from a set of 7 tones defined by IRIG(Inter-Range Instrumentation Group) in the audio frequency range. The MHA(Modified High alphabet) command adds a security feature to the secure tone command by using the predefined difference code. In order to check the function and performance of MHA FTSR, which is under development, for KSLV-II, the testbed should have functions of RF signal generation, receiver's output port monitoring, RS-422 communication and test data management. In this paper, we first briefly introduce MHA command and FTSR interface, and then show the LavVIEW based testbed include its H/W configuration, S/W implementation and test results.

• Journal of the Korean Institute of Telematics and Electronics T
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• v.36T no.1
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• pp.41-50
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• 1999

The brushless DC motor is widely being used in unmanned factories for its easy maintenance and characteristics of controllability. In this paper, we designed a speed control servo system of a sinusoidal type bmshless DC motor which has high efficiency and usefulness in the industrial fields. This servo system is realized by a controller which is required for driving motors and a new auto-tuning PI control algorithm. The DSP(Digita1 Signal Processor) is adopted as a main controller and a sensor signal processor owing to its fast computational capability and suitable architecture. Also, the hardware PWnl(Pulse Width Modulation) current controller is implemented to pursue a speed command exactly. By experimental results, it is verified that the speed response is pursued fast after command value and the steady-state response is well converged for command value variation without overshoots.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.7A
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• pp.807-813
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• 2004

This paper corresponded to Smart-UAV(Smart Unmanned Aerial Vehicle) technology development, a part of “The 21th Century New-Frontier Development Project” being propelled in accordance with enlarging the necessity of concentration development by selecting our strong technique being able to compete in the international society of knowledge based economy in the 21th century. Also, we designed Ku-band airborne video transceiver system performing to receive the TC(Tele-Command) signal needed to be applicable of Smart-UAV, and send the video and TM(Tele-Metry) signal at the same time. Moreover, we analyzed it in order to satisfy the system request of designed whole communication system, and established the validity on this paper going through by module simulation and manufacture of the whole system.

• Journal of the Korea Institute of Military Science and Technology
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• v.18 no.1
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• pp.37-45
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• 2015

These days many systems use the gps signal to get their own position. Because it's cheap and accurate and convenient. But, the strength of gps signal is very weak and can be easily interrupted by GPS jamming and GPS spoofing. Normally, fighter can use DME, TACAN, etc to correct their position error when GPS is not working. But, many aircraft which does not have those kinds of hardware need to pay additional cost to get it. In this paper, we propose how to overcome GPS jamming and GPS spoofing by only using data link system. The main purpose of this paper is to make the data link protocol to get an exact position information of own unit at gps error environment.

• 전기의세계
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• v.18 no.6
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• pp.33-45
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• 1969

The purpose of this paper is design the most important part of sequential control systems, that is, command-treatment part, from the signal-transformation point of view. An orderly procedure is developed by which for sequential control systems the experimental design method can be reduced to the rational design method. Important in this procedure are: 1. To make total block diagram of sequential control systems by determining input and output signals of command-treatment part. 2. To partition over-all block diagram by observing each output signal. 3. To design concretely minimum block diagram by using the operational block diagram. By applying the method for partitioning the circuit to the design, the design method for sequential control systems is organized and done rationally without the aid of experiece.

• The Transactions of the Korean Institute of Power Electronics
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• v.17 no.3
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• pp.259-265
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• 2012

This paper introduces a method for design and implementation of a current controller for boost converter operating in continuous conduction mode (CCM) using a digital signal processor (DSP). A Proportional-Integral (PI) type current controller outputs an average voltage command for inductor, used in the input side of the boost converter, and the duty-ratio of PWM (pulse width modulation) signal for switching device is directly calculated from the average voltage command. The gains of the PI current controller are selected such that the current response characteristics are the same as those of a first-order low-pass filter. The proposed current control scheme is implemented using a DSP based on fixed-point math operations and an experimental study has been performed to validate the proposed method.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.4 s.181
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• pp.83-90
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• 2006

A robot manipulator is usually operated in two modes: free and constrained motion modes, depending on whether the robot is in contact with an environment or not. At the moment of contact, an impact occurs and can exert harmful effects to the robot or the object. In case of teleoperation, since a user may give an inadequately excessive velocity command to the slave due to insufficient visual information, the robot nay collide the object with an excessive speed and it possibly deteriorates the robot's performance causing vibrations and at worst, shortens its lifetime by its fracture. In this article, a new algorithm is proposed by introducing a command signal modification method on the basis of impedance control and validity of the proposed algorithm is demonstrated by performing simulations and experiments.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.274-274
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• 2000

In the future, the convenient speech command system will become an widely-using interface in automation systems. But the previous research in speech recognition didn't give satisfactory recognition results for the practical realization in the noise environment. The purpose of this research is the development of a practical system, which reliably recognizes the speech command of the registered users, by complementing an existing research which used the image information with the speech signal. For the lip-reading feature extraction from a image, we used the DWT(Discrete Wavelet Transform), which reduces the size and gives useful characteristics of the original image. And to enhance the robustness to the environmental changes of speakers, we acquired the speech signal by stereo method. We designed an economic stand-alone system, which adopted a Bt829 and an AD1819B with a TMS320C31 DSP based add-on board.

• Journal of Sensor Science and Technology
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• v.9 no.6
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• pp.448-454
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• 2000

This paper describes the implementation of a multi-subject, multi-channel optical telemetry system for the short range measurement of electrocardiograms (EKGs) a system which receives command signals and transmits physiological signals to the external system using LED (Light Emitting Diode) and PD (Photodiode). This system decreases the dependency of power supply voltage to the CMOS IC chips and a new enforced synchronization technique using infrared bi-directional communication has also been proposed. The telemetry IC with the size of $5.1{\times}5.1mm^2$ has the following functions: receiving of command signal, initialization of internal state of all functional blocks, decoding of subject selection signal, time division multiplexing of 4-channel modulated physiological signals, transmission of modulated signals to external system, and auto power down control.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.929-933
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• 2004

A robot manipulator is usually operated in two modes: free motion and constraint motion according to the fact whether the robot comes into contact with the environment or not. At the moment of contact, impact occurs, and sometimes, it can possibly degrade the robot's performance such as vibration and at worst, shortens its lifetime. In this article, a new proposed algorithm is described by introducing a command signal modification method on the basis of impedance control and a validity of the proposed algorithm is demonstrated by showing the simulation study.