• 한국항행학회논문지
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• 제11권4호
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• pp.388-393
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• 2007

변환부호화기(Transform coders)를 설계함에 있어서 비트 할당(Bit allocation)은 중요한 설계 요인 중의 하나이다. 본 논문에서는 고해상(high-resolution) 이론에 의한 수식들을 바탕으로 각 계수 양자화기들의 비트율을 정수값으로 할당해주는 최적의 알고리즘인 최대 탐욕 알고리즘과 최소 탐욕 알고리즘을 제안하였다. 특히, 제안된 최대 탐욕 알고리즘과 최소 탐욕 알고리즘에서 쌍대성(duality) 성질을 확인할 수 있었다.

• 한국재료학회지
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• 제17권12호
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• pp.676-681
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• 2007

According to progress rapidly digitalization, networked and mobilization of electronics industry, there are demands for being smaller, thinner, more light, and more efficient complex functions of electronic devices which are wireless devices, semi-conductors, packages and mobile devices. Therefore, the solder resist on a printed circuit board have been required with the high resolution and the eco-friendly materials in the surface treatments such as high heating process and coating process with electrolysis. In this study, the photoinitiator initiator and monomers of the solder resist were prepared with their contents for reducing the occurrence of the under-cut. We investigated the sample surface by UV/VIS spectrometer, FT-IR, OM after HASL and ENIG process. From our results, it is possible to get a high adhesion of resist with optimal contents between the photoinitiator initiator and monomers after surface treatments.

• 대한의용생체공학회:의공학회지
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• 제15권3호
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• pp.281-288
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• 1994

In this paper, a new decomposition method of the interference EMG signal using MAMDF filtering and digital signal processor. The efficient software and hardware signal processing techniques are employed. The MAMDF filter is employed in order to estimate the presence and likely location of the respective templates which may include in the observed mixture, and high-resolution waveform alignment is employed in order to provide the optimal combination set and time delays of the selected templates. The TMS320C25 digital signal processor chip is employed in order to execute the intensive calculation part of the software. The method is verified through a simulation with real templates which are obtain ed from needle EMG. As a result, the proposed method provides an overall speed improvement of 32-40 times.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 학술대회 논문집 정보 및 제어부문
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• pp.195-197
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• 2005

In the scalable extension of H.264/AVC, spatial scalability is provided residual information as encoding layered spatial resolution between layers. We use the inter-layer prediction to remove this redundancy. In the inter-layer prediction, as the prediction we can use the signal that is the upsampled signal of the lower resolution layer. In this case, coding efficiency can be different from optimal prediction by kinds of interpolation filter. This paper indicates technique to choose the interpolation filter and to enhance coding efficiency for finding more correct prediction in intra macroblock.

• 대한전기학회논문지:시스템및제어부문D
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• 제51권10호
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• pp.460-467
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• 2002

This paper proposes new motion vector re-estimation techniques for transcoding of heterogenous video coders. The first case is for transcoder of coding format. The coding algorithm with B-picture like MPEG standards is transcoded into the different algorithm without B-picture like H.261 standards. The second case is for transcoder of spatial resolution reduction. It generates a downscaled video bitstream at the video source. The third case is the integrated method that previous two cases are needed simultaneously. These three transcoding algorithms are compared and verified though reconstructed image quality in PSNR, motion vector errors between optimal motion vectors of cascaded trans- coder and motion vectors estimated by proposed methods and the amount of operation.

• 응용통계연구
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• 제5권1호
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• pp.19-28
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• 1992

본 논문에서는 부분균형배열을 이용하여 $2^t$ 요인 실험계획에서 최소의 실험횟수를 가지 고 2인자 교호작용까지 분석할 수 있고, 추정량의 분산-공분산행렬이 균형을 이루고 있는 실험계획법을 기술하였다. 그리고 제안된 실험계획법의 최적성을 검토하여 트레이스 최적실 험계획을 찾아보았다. 이러한 최소균형 Resolution V $2^t$요인 부분실험법은 직교배열을 이용하여 주효과만 분석하는 기존의 다구찌방법과는 달리 2인자 교호작용까지 분석하고자 할 때 효과적으로 사용될 수 있으며 그 응용방법을 검토하였다.

• 지구물리와물리탐사
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• 제7권1호
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• pp.33-40
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• 2004

Numerical and laboratory studies have been conducted to test the ability of Electrical Resistance Tomography-a technique used to map the electrical resistivity of the subsurface-to delineate contaminant plumes. Two-dimensional numerical models were created to investigate survey design and resolution. Optimal survey design consisted of both downhole and surface electrode sites. Resolution models revealed that while the bulk fluid flow could be outlined, small-scale fingering effects could not be delineated. Laboratory experiments were conducted in a narrow glass tank to validate theoretical models. A visual comparison of fluid flow with ERT images also showed that, while the bulk fluid flow could be seen in most instances, fine-scale effects were indeterminate.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 하계학술대회 논문집 B
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• pp.823-825
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• 1995

This paper presents an efficient and robust robot path planning technique that can always find a path, if one exists, in a densely cluttered, unknown and unstructured obstacle environment. The terrain in which the robot is expected to navigate is represented as a tesselated grid of square cells. The generated path is resolution complete and also resolution optimal once the terrain is fully explored by the robot or all the information about the terrain is given. The technique enables the accurate wave propagation to the diagonally adjacent cells and facilitates the implementations of various essential features for a real-time path planner such as partial updates and parallel computations.

• Bulletin of the Korean Chemical Society
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• 제25권1호
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• pp.101-105
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• 2004

The laser ablation/ionization time-of-flight mass spectrometry is applied to the isotopic analysis of solid samples using a home-made instrument. The technique is convenient for solid sample analysis due to the onestep process of vaporization and ionization of the samples. The analyzed samples were lead, cadmium, molybdenum, and ytterbium. To optimize the analytical conditions of the technique, several parameters, such as laser energy, laser wavelength, size of the laser beam on the samples surface, and high voltages applied on the ion source electrodes were varied. Low energy of laser light was necessary to obtain the optimal mass resolution of spectra. The 532 nm light generated mass spectra with the higher signal-to-noise ratio compared with the 355 nm light. The best mass resolution obtained in the present study is ~1,500 for the ytterbium.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송∙미디어공학회 2020년도 추계학술대회
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• pp.228-229
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• 2020

최근 딥러닝 기술은 여러 컴퓨터 비전 응용 분야에서 많이 쓰이고 있다. 물체 인식, 분류 및 영상 생성 등을 예로 들 수 있다. 특히 초고해상도 변환 문제에서 최근 딥러닝을 사용하면서 큰 성능 개선을 얻고 있다. Fast super-resolution convolutional neural network (FSRCNN)은 딥러닝 기반 초고해상도 알고리즘으로 잘 알려져 있으며, 여러 개의 convolutional layer로 추출한 저 해상도의 입력 특징을 활용하여 deconvolutional layer에서 초고해상도의 영상을 출력하는 알고리즘이다. 본 논문에서는 병렬 연산 효율성을 고려한 FPGA 기반 convolutional neural networks 가속기를 제안한다. 특히 deconvolutional layer를 convolutional layer로 변환하는 방법을 통해서 에너지 효율적인 가속기를 설계했다. 또한 제안한 방법은 FPGA 리소스를 고려하여 FSRCNN의 구조를 변형한 Optimal-FSRCNN을 제안한다. 사용하는 곱셈기의 개수를 FSRCNN 대비 2.4 배 압축하였고, 초고해상도 변환 성능을 평가하는 지표인 PSNR은 FSRCNN과 비슷한 성능을 내고 있다. 이를 통해서 FPGA 에 최적화된 네트워크를 구현하여 FHD 입력 영상을 UHD 영상으로 출력하는 실시간 영상처리 기술을 개발했다.