• 제어로봇시스템학회논문지
• /
• 제3권6호
• /
• pp.626-631
• /
• 1997

This paper represents the design of a real-time image preprocessing system. The preprocessing system performs hardware-wise mask operations and thresholding operations at the speed of camera output single rate. The preprocessing system consists of the preprocessing board and the main processing board. The preprocessing board includes preprocessing unit that includes a $5\times5$ mask processor and LUT, and can perform mask and threshold operations in real-time. To achieve high-resolution image input data($20485\timesn$), the preprocessing board has a linescan camera interface. The main processing board includes the image processor unit and main processor unit. The image processor unit is equipped with TI's TMS320C32 DSP and can perform image processing algorithms at high speed. The main processor unit controls the operation of total system. The proposed system is faster than the conventional CPU based system.

• Journal of Welding and Joining
• /
• 제32권3호
• /
• pp.74-80
• /
• 2014

Due to environmental regulations (RoHS, WEEE and ELV) of the European Union, electronics and automotive electronics have to eliminate toxic substance from their devices and system. Especially, reliability issue of lead-free solder joint is increasing in car electronics due to ELV (End-of-Life Vehicle) banning from 2016. We have prepared engine control unit (ECU) modules soldered with Sn-40Pb and Sn-3.0Ag-0.5Cu (SAC305) solders, respectively. Degradation characteristics of solder joint strength were compared with various conditions of automobile environment such as cabin and engine room. Thermal cycle test (TC, $-40^{\circ}C$ ~ ($85^{\circ}C$ and $125^{\circ}C$), 1500 cycles) were conducted with automotive company standard. To compare shear strength degradation rate with eutectic and Pb-free solder alloy, we measured shear strength of chip components and its size from cabin and engine ECU modules. Based on the TC test results, finally, we have known the difference of degradation level with solder alloys and use environmental conditions. Solder joints degradation rate of engine room ECU is superior to cabin ECU due to large CTE (coefficient of thermal expansion) mismatch in field condition. Degradation rate of engine room ECU is 50~60% larger than cabin room electronics.

• 전력전자학회논문지
• /
• 제25권4호
• /
• pp.293-302
• /
• 2020

This study proposes a triple-loop current control method for the auxiliary power unit of fuel cell trains. The auxiliary power unit of fuel cell trains has a grid-connected function when power is supplied to the utility grid. Moreover, the auxiliary power unit of trains has a 1500 V DC link voltage; thus, PWM frequency cannot be increased to a high frequency. Owing to this low PWM frequency condition, creating a triple-loop design is difficult. In this study, a triple-loop controller is developed for a capacitor voltage controller in standalone mode that operates as an auxiliary power supply for trains and for a grid current controller in grid control mode with an inner capacitor voltage controller. The voltage controller employs an inductor current controller inner loop. To overcome low PWM frequency, a design method for the bandwidth of the capacitor voltage controller considering the bandwidth of the inner inductor current controller is described. The effectiveness of the proposed method is proven using PSIM simulation.

• 대한전자공학회논문지
• /
• 제27권5호
• /
• pp.775-783
• /
• 1990

In this paper we implemented the fast thinning unit by modifying the pipeline architecture which was proposed by Stanley R. Sternberg. The unit is useful in preprocessing such as image representation and pattern recognition etc. This unit is composed of interface part, local memory part, address generation part, thinning processing part and control part. In thinning processing part, we shortened the thinning part which performed by means of look up table using window mapping table. Thus we improved the weakness of SAP, in which the number of delay pipeline and window pipeline are equal to image column size. Two independent memorys using tri-state buffer enable the two direction flow of address generated by address generation part. This unit avoids the complexity of architecture and has flexibility of image size by means of simple modification of logic bits.

• 전자공학회논문지C
• /
• 제34C권11호
• /
• pp.20-28
• /
• 1997

In this paper, quantization and inverse quantizatio unit, a sa component of MPEG-2 moving picture compression system, ar edesigned. In the processing of quantization, this design adopted newly designed arithmetic units in which quantization matrices and scale code was expressed with SD(signed-digit) code. In the arithmetic unit of inverse quantization, quantization scale code, which has 5-bits length, is splited into two pieces; 2-bits for control code, 3-bits for quantization data, and the method to devise quantization step size is proposed. The design was coded with VHDL and synthesis results in that it consumed about 6,110 gates, and operating speed is 52MHz.

• 한국정보처리학회논문지
• /
• 제2권3호
• /
• pp.277-287
• /
• 1995

멀티미디어 통신 단말기를 이용하여 다자간 영상회의를 구현하기 위하여 단말기들 은 논리적으로 상호 연결되어 있어야 하며, 단말기 사이의 연결을 구현하는 방법에는 중앙 집중식 방식과 분산식 방식이 있다. 이중 집중식 영상회의의 구현을 위하여 다 지점 제어 장치가 필요하며, 이러한 다지점 제어장치를 설계하기 위한 방법에는 음성 및 영상처리 장치의 개발 방법에 따라 디지탈에 의한 방식과 아날로그에 의한 방식으 로 크게 나눌 수 있다. 이러한 다지점 제어장치의 의미 및 개발방법을 살펴보기 위하 여, 본 논문에서는 다지점 제어 장치에 대한 주요기능을 정리하였으며, 다지점 제어장 치의 구현을 위한 여러 방법들을 제시하였다.

• 전자공학회논문지B
• /
• 제33B권5호
• /
• pp.152-158
• /
• 1996

A novel resonant pulse control technique which generates high-quality sinusoidal output voltage from a resonant dc link inverter is presented for UPS applicatons. The proposed control technique limits resonant voltae overshoot without any passive or active clamp circuit, resulting in resonant pulses iwth uniform amplitude and high efficiency. The output voltage is controlled by the third order contorller iwth an inner loop of th efilter inductor current and the feedforward controller. Analysis and design of the proposed control technique are illustrated and verified on a 5kVA experimental unit.

• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 2004년도 학술대회지
• /
• pp.836-841
• /
• 2004

This paper describes ASIC design for brightness revision control, A LED Pixel Matrix (LPM) design and LPM in natural color LED vision. A designed chip has 256 levels of gradation correspond to each Red, Green, Blue LED pixel respectively, which have received 8bit image data. In order to maintain color uniformity by reducing the original rank error of LED, we adjusted the specific character value 'a' and brightness revision value 'b' to pixel unit, module unit and LED vision respectively by brightness characteristic function with 'Y=aX+b'. In this paper, if designed custom chip and brightness revision control method are applied to manufacturing of natural color LED vision, we can obtain good quality of image. Furthermore, it may decrease the cost for manufacturing LED vision or installing the plants.

• 한국산학기술학회논문지
• /
• 제13권6호
• /
• pp.2428-2434
• /
• 2012

본 논문은 제동 시스템에서 전자식 주행안정 제어장치(ESC)의 유압 모듈레이터의 솔레노이드 밸브 제어에 대한 것이다. ESC의 전자제어유니트(ECU)를 제어하기 위한 방법으로 고주파수 제어와 슬로프 제어를 적용하였으며, 서지 압력 및 전자파간섭(EMI) 저감 특성을 연구하였다. 고주파수에서의 전자파 방출을 줄이기 위하여 ECU 출력 단에 슬로프 제어 기능을 추가하였다. 측정결과 제동 시스템에서 고주파수 ECU의 솔레노이드 밸브제어 방법에 따라 서지 압력과 전자파 방출이 저감될 수 있음을 확인하였다. 결론적으로 고주파수 ECU 제어 연구 결과에 의해 제동 시스템 성능을 향상방안을 제시하고자 한다.

• Journal of Power Electronics
• /
• 제5권1호
• /
• pp.62-66
• /
• 2005

A simple fault correction method for rotor position detection of a brushless DC(BLDC) motor with trapezoidal back EMF(electromotive force) using a Hall effect latch unit is presented. The reason why the Hall effect latch unit does not operate properly during the startup of a BLDC motor is thoroughly explained. To solve this problem, a simple code change method and its hardware implementation issues are proposed and discussed.