• Journal of Biomedical Engineering Research
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• v.16 no.1
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• pp.101-106
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• 1995

In this paper, the patient monitor consisting of ECG/Respiration Amplification, Front end CPU, Main CPU, Main Controller, Video Amplifier, Display Controller, Waveform Generator, Bus & Power Supply, 8097 Processor was developed. This patient monitor measures the patient's states in the hospital such as elecctro-cardiography, respiration, blood pressurae and temperature. The control and processing methods based on micro-processor employ the flexibility, extensibility over other conventional system. The followings are incorporated in this system. First, ECG/RESP measures the respiration by impedence pneumography. Second, FECPU utilizes an Intel 8031 microcontroller. Third, Controller function originate from a LSI CRT controller.

• Journal of Biomedical Engineering Research
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• v.15 no.1
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• pp.1-8
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• 1994

Electrofusion of cabbage protoplasts was performed with a developed equipment which consists of a parallel wire electrode, a AC field generator, and a pulse generator. Exposure of protoplasts to an alternating current field of 450 KHz causes attraction to each other which leads to chains of protoplasts extending from the electrode. Intra-specific protoplast fusion was effectively induced within the pearl chains by the additional application of a single high-intensity DC square wave pulse of 1 KV/cm for 1-3 msec. To improve the performance, micro fusion electrode fabricated from the semiconductor technology and microcontroller based field an, d pulse generator was proposed. The viability of protoplasts after an application of electric field at optimum condition was reduced by only 5 % compared with that of pre-application. A prototype of fusion electrode, which consists of insulator-structure, was successfully fabricated by using photosensitive polyimide.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.05
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• pp.330-333
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• 1997

In this paper, we designed a low power and small-sized, light weighted intelligent ambulatory monitoring system using a flash memory card. The system's hardware specifications are as follows: 2 channels, 8bit/250Hz sampling rate, 20M byte storage capacity, a single-chip microcontroller (68HC11E9). To easily interface with PC based system, FFS(Flash File System) was used. We obtained the QRS detection rate of 99.14 through the evaluation with MIT/BIH database.

• Proceedings of the KIPE Conference
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• 2004.07b
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• pp.587-591
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• 2004

This paper proposes a novel current compensation technique that can eliminate the harmonic currents included in line currents without computation of harmonic current components. A current controller with fast dynamics for an active filter is described. Harmonic currents are directly controlled without the need for sensing and computing the harmonic current of the load current, thus simplifying the control system. Current compensation is done in the time domain, allowing a fast time response. The DC voltage control loop keeps the voltage across the DC capacitor constant. High power factor control by an active filter is described. All control functions are implemented in software using a single-chip microcontroller, thus simplifying the control circuit. Any current-controlled synchronous rectifier can be used as a shunt active filter through only the simple modification of the software and the addition of current sensors. It is shown through experimental results that the proposed controller gives good performance for the shunt active filter.

• Proceedings of the KIPE Conference
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• 2008.06a
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• pp.225-227
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• 2008

This paper deals with the implementation on a Field Programmable Gate Array (FPGA) of PWM switching patterns for a voltage multilevel inverter. The reference data in main microcontroller is transmitted to the FPGA through 16 general purpose I/O ports. Herein, three-phase reference voltage signals are addressed by the last 2-bit (bit 15-14) and their data are assigned in remaining 14-bit, respectively. The carrier signals are created by 16-bit counter in up-down counting mode inside FPGA according to desirable topology. Each reference signal is compared with all carrier signals to generate corresponding PWM switching patterns for control of the multilevel inverter. Useful advantages of this scheme are easy implementation, simple software control and flexibility in adaptation to produce many PWM signals. Some simulations and experiments are carried out to validate the proposed method.

• Proceedings of the Korea Information Processing Society Conference
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• 2003.11a
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• pp.431-434
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• 2003

과거 임베디드 시스템은 산업용 같은 특수한 경우와 여러 전자 제품에서 눈에 뛰지 않는 형태로 사용이 되어 왔지만 최근 들어 정보통신 분야가 발전하고 가격 대 성능비가 우수한 Microcontroller 와 CPU 들이 등장하면서 더욱 더 각광을 받기 시작했다. 이들의 개발환경은 C 언어와 어셈블리어가 주를 차지하고 있는데 개발상의 많은 장점 때문에 C 언어를 선택하여 사용하고 있지만 target machine 의 C 컴파일러가 전부 제공되지 않고 일부 machine 만 제공되고 있기 때문에 C 언어의 사용은 아직 제한적이다. 이에 본 논문에서는 Retargetable Compiler 인 LCC 를 이용하여 임베디드용 machine 에 대해 retargeting 이 가능하도록 LCC 를 개선시키고자 한다.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.423-426
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• 1996

The conditions to be satisfied with SOC(State-of-Charge) indicator installed on the electric vehicle were that it should be used under frequent loading conditions and that it should enable the monitor to adjust to the aging effect. But, the state-of-charge test requires a lengthy stabilization period after discharge cycles and the ampere-hour test requires the knowledge of the battery capacity in terms of amp-hours. However, a monitoring technique combining the state-of-charge test to enable the monitor to adjust to the aging effect with the ampere-hour test to use under frequent loading condition is studied and implemented on a microcontroller-based circuit in this paper. Specially, optical fiber is used to realize hydrometer which is immune to electromagnetic interference and toxic environment and makes it possible to be used in a wide temperature range.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.449-452
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• 2005

For home networking system with a function of air quality monitoring, a wireless sensor module with several air quality monitoring sensors was developed for indoor environment monitoring system in home networking. The module has various enlargements for various kinds of sensors such as humidity sensor, temperature sensor, CO2 sensor, flying dust sensor, and etc. The developed wireless module is very convenient to be installed on the wall of a room or office, and the sensors in the module can be easily replaced due to well designed module structure and RF connection method. To reduce the system cost, only one RF transmission block was used for sensors' signal transmission to 8051 microcontroller board in time sharing method. In this home networking system, various indoor environmental parameters could be monitored in real time from RF wireless sensor module. Indoor vision was transferred to client PC or PDA from surveillance camera installed indoor or desired site. Web server using Oracle DB was used for saving the visions by web-camera and various data from wireless sensor module.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.947-950
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• 2005

In this paper, we present an approach to control the locomotion of snake robot with concurrent programming model constructed using threads and semaphores. The multi-thread based concurrent programming model adds the flexibility to design and synchronize the movement of snake robots as compared with microcontroller and mechanical based approaches. We have designed a physical snake robot using LEGO sensors and actuator blocks and the wave motion of the snake robot is generated by multi-thread based concurrent programming under RT-Linux. The different robot movements in a desired direction along with different types of snake movements are achieved using angle sensors.

• Proceedings of the IEEK Conference
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• 1998.06a
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• pp.847-850
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• 1998

One of the most difficult problem of designing VLSI is a mixed-circuit design, that is to design circuit containing both analog parts and digital parts. Digital to analog converter and analog to digital converter is a typical case. Especially it can be a serious problem when mixed circuit are put into a large digital circuit like microcontroller. However nowadays this problem is settled by separating analog circuit parts outside the IC. This technique is based on converting a digital signal into a pulse sequence. Then an analog signal is obtained by averaging this pulse sequence at the external low-pass filter. An anlog to digital converter is designed using a stochastic logic instead of a traditional PWM (pulse-width modulation) signal and ins implemente dusing FPGa. Stochastic pulse sequence can be made as a simple circuits and moreover can be mathematically processed by simple circuits -AND gates. The spectral property of stochastic pulse sequence method is better than that of PWM method. So it make easy to design a external low-pass filter. This technique has important advantages, especially the reduction of the ADC cost.