• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 추계학술대회 논문집
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• pp.487-488
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• 2006

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2008년도 춘계종합학술대회 A
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• pp.925-928
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• 2008

현대 사회의 정보처리 기술은 디지털 기술을 기반으로 하여 빠르게 성장하고 있다. 이러한 디지털 처리기술은 신호를-음성 및 영상처리- 전달하고 해석하는 과정에서 다양한 방법을 사용하여 신호를 획득, 저장하고 있다. 효과적인 신호처리를 위해 다양한 필터가 사용되고 있으며 대표적인 디지털 필터로써는 FIR 필터와 IIR 필터가 있다. 디지털 FIR 필터는 IIR 필터에 비해 안정적이며, 선형위상 응답특성을 갖고 있다. 하지만, 디지털 FIR 필터의 불연속 구간에서의 깁스현상이 발생하는 문제점을 가지며 이것을 극복하는 것이 주요한 관건이라 하겠다. 따라서 본 논문에서는 창함수를 이용한 FIR 필터를 제시하였으며, 기존에 사용한 창함수와 비교를 통하여 성능의 우수함을 나타내었다.

• 한국컴퓨터정보학회논문지
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• 제9권2호
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• pp.49-56
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• 2004

본 논문에서는 디지털 영상을 효과적으로 처리하기 위한 에지 클래스를 설계한다. 에지는 디지털 영상에서 물체를 검출하거나 인식하기 위한 핵심적인 형태정보를 포함하는 기초자료로 사용되는 중요한 정보이다. 그러므로 에지를 검출한 후 검출된 에지를 효과적으로 관리하고 다양한 응용이 가능하도록 하는 것은 디지털 영상 처리에 있어 매우 중요하다 기존의 디지털 영상 처리 시스템에서 사용되던 환경은 사용 편의성이나 속도 등의 측면에서 많은 한계점을 가지고 있다. 따라서 본 논문에서는 검출된 에지를 효과적으로 관리할 수 있는 에지 클래스를 설계하고, 이를 에지 검출 알고리즘을 이용하여 테스트해봄으로써 기존의 방법과 비교 분석해 본다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 신호처리소사이어티 추계학술대회 논문집
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• pp.27-30
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• 2003

In this paper a new approach of digitalized ‘Takbon’ is introduced. By image signal processing, the letters which were written on stones can be deciphered. Epigraphic letter is detected by digital image device, digital camera. The two dimensional digital image is preprocessed because of sensor noise and detective turbulence. Color image is transformed into grey level. The letter image is analyzed in time/frequency domain. By the resultant analysis data decisive functions are calculated. Signal Processing techniques, such as scaling, clipping, digital negative, high/low filter, morphology and so on, provide algorithms that can extract letter from stones.

• 치과방사선
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• 제29권2호
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• pp.387-396
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• 1999

In dentistry. RadioVisioGraphy was introduced as a first electronic dental x-ray imaging modality in 1989. Thereafter. many types of direct digital radiographic system have been produced in the last decade. They are based either on charge-coupled device(CCD) or on storage phosphor technology. In addition. new types of digital radiographic system using amorphous selenium. image intensifier etc. are under development. Advantages of digital radiographic system are elimination of chemical processing, reduction in radiation dose. image processing, computer storage. electronic transfer of images and so on. Image processing includes image enhancement. image reconstruction. digital subtraction, etc. Especially digital subtraction and reconstruction can be applied in many aspects of clinical practice and research. Electronic transfer of images enables filmless dental hospital and teleradiology/teledentistry system. Since the first image management and communications system(IMACS) for dentomaxillofacial radiology was reported in 1992. IMACS in dental hospital has been increasing. Meanwhile. researches about computer-assisted diagnosis, such as structural analysis of bone trabecular patterns of mandible. feature extraction, automated identification of normal landmarks on cephalometric radiograph and automated image analysis for caries or periodontitis. have been performed actively in the last decade. Further developments in digital radiographic imaging modalities. image transmission system. imaging processing and automated analysis software will change the traditional clinical dental practice in the 21st century.

• Journal of Information Processing Systems
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• 제10권2호
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• pp.223-239
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• 2014

New IIR digital differintegrators (differentiator and integrator) with very minor absolute relative errors are presented in this paper. The digital integrator is designed by interpolating some of the existing integrators. The optimum value of the interpolation ratio is obtained through linear programming optimization. Subsequently, by modifying the transfer function of the proposed integrator appropriately, new digital differentiator is obtained. Simulation results demonstrate that the proposed differintegrator are a more accurate approximation of ideal ones, than the existing differintegrators. Furthermore, the proposed differentiator has been tested in an image processing application. Edges characterize boundaries and are, therefore, a problem of fundamental importance in image processing. For comparison purpose Prewitt, Sobel, Roberts, Canny, Laplacian of Gaussian (LOG), Zerocross operators were used and their results are displayed. The results of edge detection by some of the existing differentiators are also provided. The simulation results have shown the superiority of the proposed approach over existing ones.

• 방송공학회논문지
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• 제9권4호
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• pp.357-370
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• 2004

본 논문에서는 ATSC 디지털 TV (DTV) 시스템의 등화형 동일 채널 중계기(Equalization Digital On-Channel Repeater)를 위한 복조, 등화, 그리고 재변조로 구성된 디지털 신호 처리(Digital Signal Processing: DSP) 기술들을 제안한다. EDOCR에서의 신호처리 과정에 의해 발생기는 시스템 지연은 기존 수신기의 수신 성능 저하를 야기할 수 있기 때문에 가능한 그 지연을 최소화 하여야 한다. 본 논문에서 제안한 DSP 기술들은 EDOCR의 성능 저하를 최소화 하면서 시간 지연을 줄일 수 있도록 하였다. 또한, 본 논문에서는 전산 실험을 통해 하드웨어 구현에 적합한 필터의 탭 수를 다양하게 제시한다.

• 천문학논총
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• 제22권3호
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• pp.63-73
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• 2007

In this paper, we introduce the performance test results of digital data processing system for KVN (Korean VLBI Network). The digital data processing system for KVN consists of DAS (Data Acquisition System) and high-speed recorder which called Mark5B system. DAS system performs the digitalization of analog radio signal through ADS-1000 gigabit sampler with 1 Gsps/2-bit and process the digital filtering of digital signal. Mark5B system records the output data of DFB (Digital Filter Bank) with about 1 Gbps. In this paper, we carried out the preliminary evaluation experiments of the KVN digital data processing system connected between DAS system and Mark5B with VSI (VLBI Standard Interface) interface which is designed for compatible in each VLBI system. We first performed all of the KVN digital data processing system connected by VSI interface in the world. In factory inspection phase, we found that the DAS system has a memory read/write error in DSM (Digital Spectrometer) by analyzing the recorded data in Mark5B system. We confirmed that the DSM memory error has been correctly solved by comparing DSM results with Mark5B results. The effectiveness of KVN digital data processing system has been verified through the preliminary experiments such as data transmission, recording with VSI interface connection and data analysis between DSM and Mark5B system. In future work, we will perform the real astronomical observation by using the KVN 21m radio telescopes so as to verify its stability and performance.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 1996년도 Proceedings International Workshop on New Video Media Technology
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• pp.50-55
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• 1996

Multimedia boom has happened worldwide these days. In multimedia, we use several kinds of media such as character, figure, voice, music, still images, moving picture etc.. Then I think image including moving picture is the most effective and important media for human being. Creating digital images using a computer has the following two main approaches, depending on how the computer is used. 1. CG Technology. Created images, produced through computer graphics. 2. Digital Image Processing. Images processed through digital image processing technologies. Approach (1) is very popular as Computer Graphics. Two-dimensional and three-dimensional computer graphics techniques are used over wide applications today. On the other hand, Approach (2), which uses digital image processing technology, has been attracting attention lately, in the filed of movies and television. In this report, I will introduce these approaches of CG and digital image processing, and show some application fields such as current movies.

• 대한임베디드공학회논문지
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• 제14권1호
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• pp.33-41
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• 2019

We propose an embedded solution to design a high-speed and high-accuracy 16bit analog-digital signal processing interface for the control systems using various external analog signals. Choosing TMS320F28377D micro controller unit (MCU) featuring high-performance processing in the 32-bit floating point operation, low power consumption, and various I/O device supports, we design and build the proposed system that supports both 16-bit analog-digital converter (ADC) interface and high precision digital-analog converter (DAC) interface. The ADC receives voltage-level differential signals from fully differential amplifiers, and the DAC communicates with MCU through 50 MHz bandwidth high-fast serial peripheral interface (SPI). We port the boot loader and device drivers to the implemented board, and construct the firmware development environment for the application programming. The performance of the entire implemented system is demonstrated by analog-digital signal processing tests, and is verified by comparing the test results with those of existing similar systems.