• The Transactions of the Korea Information Processing Society
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• v.6 no.1
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• pp.182-192
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• 1999

The advance of the MPEG(Moving Picture Expert Group) and DSP(Digital Signal Processing) technologies lead the energence of the information appliances which are gradually digitalized and embedded the high-speed networking function. This paper proposes a CHANCE(Cost-effective Home ATM Network for the Consumer Electronics) protocol supporting the ATM-based high-speed networking between the information appliances within the home, and designs its specific functions including the network management and signalling function. The CHANCE protocol is basically based on the tree topology, and supports the plug-and-play function by using only the header field of the ATM cells. Unlike the existing ATM Warren protocol which uses the source routed addressing scheme to control the in-home devices from the Warren controller, the CHANCE protocol can support the inter-device controls as well as the controls from the CHANCE controller by using the switch and device identifier.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.45 no.7
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• pp.17-22
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• 2008

This paper presents a low-power and small-area pulse width modulator by light intensity for photoflash. Light intensity controller is achieved by using capacitor, photodiode, and comparator. The proposed circuit designs digital circuit to reduce static power consumption except comparator. And IGBT driver has short circuit protection using delay cell. The pulse width modulator has the operating range of $V_{MS}$ from 0.5V to 2.5V and pulse width of output from 0.14ms to 1.65ms at 300Hz. The pulse width modulator fabricated in $0.35-{\mu}m$ CMOS technology occupies $0.85mm{\times}0.56mm$. This circuit consumes 3.0mW at 300Hz and 3.0V.

• 제어로봇시스템학회:학술대회논문집
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• 1992.10a
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• pp.537-540
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• 1992

This paper presents Samsung CNC (Computer Numerical Controller) system with an intel 80486/487 as the main CPU and a 32 bit floating point DSP(Digital Signal Processor) TMS320C30 as the motion control CPU. The Samsung CNC system diverse user-frienly characteristics such as multi-tasking, powerful menu system, internal PLC system, and 2/3 dimensional graphics in wire and solid mode. The main CPU executes central processing program, user interface program, interpreter, BMI, etc while the motion control CPU carries out some interpolations, acceleration/deceleration, and PID control algorithm with feedforward terms. Complex interpolations except linear and circular ones are performed on the main control CPU. The experimental results for the circular interpolation under linear acceleration/deceleration shows that the proposed CNC system can be widely used in controlling machining centers with good machining accuracy.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.12
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• pp.1678-1687
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• 2013

This paper describes a prototype of 3-phase 3.3kV/220V 6kVA modular semiconductor transformer developed in the lab for feasibility study. The developed prototype is composed of three single-phase units coupled in Y-connection. Each single-phase unit with a rating of 1.9kV/127V 2kVA consists of a high-voltage high-frequency resonant AC-DC converter, a low-voltage hybrid-switching DC-DC converter, and a low-voltage hybrid-switching DC-AC converter. Also each single-phase unit has two DSP controllers to control converter operation and to acquire monitoring data. Monitoring system was developed based on LabView by using CAN communication link between the DSP controller and PC. Through various experimental analyses it was verified that the prototype operates with proper performance under normal and sag condition. The system efficiency can be improved by adopting optimal design and replacing the IGBT switch with the SiC MOSFET switch. The developed prototype confirms a possibility to build a commercial high-voltage high-power semiconductor transformer by increasing the number of series-connected converter modules in high-voltage side and improving the performance of switching element.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.3
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• pp.467-472
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• 2006

This study has been done to design a precise system and develop position control algorithm to control a Composite Smoke Bomb Azimuth driving apparatus of a BLDC servo motor. Having to Blind the sight of opposite tank. the Smoke Bomb Rotational driving system needs instant response that is able to detect opponent appearance and blast the bomb at a short time. So a design that shows fast current response capability or $300[Hz]\sim500[Hz]$ is proposed. in the MIN-MAX PWM technology is used to increase the operational speed. in order to control the blasting position, a precision position control algorithm that utilizes the integral value of speed trajectory is suggested. Also these characteristics are monitored and assessed by the PC based monitoring program which shows the graphs of current, voltage, position, and speed parameters. The main controller is based on a TMS320VC33 high performance floating-point DSP(Digital Signal Process) and the PWM generator utilizes EPM7128 CPLD.

• Journal of Biosystems Engineering
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• v.37 no.6
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• pp.352-358
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• 2012

Purpose: The inexpensive black box system was developed to acquire and save driving information, to give the slope information, and to transmit SOS and theft signal. Method: The device consists of a main micro controller to acquire and save data, a GPS sensor module, a CDMA module, a touch LCD module, a RF (Radio Frequency) ID module, a SD (Secure Digital) card module, an emergency electric power source, a theftproof circuit, and a sensing device. The sensing device consists of a 8 bit micro controller, a accelerometer to detect impulse, two slope sensors to detect roll and pitch angle and a circuit to detect operation of 6 lighting devices. Results: Test results are as follows: 1) a tractor can be start up only with an electronic key (password or RFID card), 2) theft signal was transmitted when a tractor moved without an electronic key, 3) SOS was transmitted at conditions that rollover or crash happened. 4) 5 more than per 1s data are recorded at 5 minute intervals as new file name in SD card. Conclusions: This system can be used to save travelling record, reduce accident, prevent theft and rescue life in the accidents.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.44 no.4 s.316
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• pp.1-9
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• 2007

An embedded system is implemented in this work by removing PCMCIA dedicate controller chip from ARM processor based embedded Linux system. In this paper, we propose PCMCIA interface architecture by using Ad hoc methods for wireless network. The proposed system is developed based on S3C2410A processor and it is interfaced with PCMCIA socket by using combinational digital logic circuits. It is interesting to observe that Ad hoc interface provides $97.9%{\sim}102.49%$ performance when compared with dedicate controller systems. The results indicate that the proposed method simplifies the system without loss of performance.

• Spatial Information Research
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• v.9 no.2
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• pp.309-324
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• 2001

To apply the real-time kinematic GPS surveying technique, this research has tried to obtain the TOKYO datum first from the continuous reference stations distributed all over the country. Then, analysis of the geography of a coastal area including both of land and sea has been carried out by the post-processed continuous kinematic GPS technique and the real-time kinematic GPS surveying technique. After considering the initial conditions and measuring time zone for real-time kinematic GPS, post-processed and the real-time kinematic GPS measurements have been carried out. A new system has been proposed to store measured data by using a program developed to store GPS data in real time and to monitor the satellite condition through controller simultaneously. The accuracy of GPS data acquired in real time was as good as that acquired by post processing. It is expected that it will be useful for the analysis of coastal geographic characteristics because DTM can be also constructed for the harbor reclamation, the dredging and the variation of soil movement in a river.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.38 no.4
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• pp.18-26
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• 2001

In this paper, we propose an ATC(Automatic Transfer mode Controller) algorithm and an average-mode-change method for use in Gear shift PLL which can automatically change loop gain. The proposed ATC algorithm accurately detects proper timing or the mode change and has a very simpler structure - than the conventional lock detector algorithm often used in QPSK. And the proposed average mode change method can obtain low errors of estimated frequency offset by averaging the loop filter output of frequency component in shift register. These algorithms are also useful in designing ASIC, since these algorithms occupy small circuit area and are adaptable for high speed digital processing. We also present phase tracking performance of proposed Gear-shift PLL, which is composed of polarity decision PD, ATC and average mode change circuit, and analyze the results by examining constellation at each mode.

• IEMEK Journal of Embedded Systems and Applications
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• v.14 no.2
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• pp.87-96
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• 2019

Low power issue is one of the most critical problems in the Internet of Things (IoT), which are powered by battery. To solve this problem, various approaches have been presented so far. In this paper, we propose a method to reduce the power consumption by reducing the numbers of accesses into the flash memory consuming a large amount of power for on-chip software execution. Our approach is based on using cooperative logging structure to distribute the sampling overhead in single sensor node to adjacent nodes in case of rare-event applications. The proposed algorithm to identify event occurrence is newly introduced with negative feedback method by observing difference between past data and recent data coming from the sensor. When an event with need of flash access is determined, the proposed approach only allows access to write the sampled data in flash memory. The proposed event detection algorithm (EDA) result in 30% reduction of power consumption compared to the conventional flash write scheme for all cases of event. The sampled data from the sensor is first traced into the random access memory (RAM), and write access to the flash memory is delayed until the page buffer of the on-chip flash memory controller in the micro controller unit (MCU) is full of the numbers of the traced data, thereby reducing the frequency of accessing flash memory. This technique additionally reduces power consumption by 40% compared to flash-write all data. By sharing the sampling information via LoRa channel, the overhead in sampling data is distributed, to reduce the sampling load on each node, so that the 66% reduction of total power consumption is achieved in several IoT edge nodes by removing the sampling operation of duplicated data.