• 전자공학회논문지S
• /
• 제34S권5호
• /
• pp.35-44
• /
• 1997

In this paper, a an algorithm that detects the endocardial boundary, expanding the region from endocardial cavity using fuzzy inference, is proposed. This algorithm decides the ventricular cavity by fuzzy inference in process of searching each pixel from the inside of left ventricle in echocardial image and expands it. Uncertainty and fuzziness exists in decision of endocardial boundary. Therefore, we convert the lingustic representation of mean, standard deviation, and threshold value that are characteristic variables of endocardial boundary to fuzzy input and output variables. And, we extract proposed method is robuster to noise than radial searching method that is highly dependent on center position. To prove the similarity of detected boundary by fuzzy nference, we used the measures of SIZE, correlation coefficient, MSD, and RMSE and had acquired reasonable results.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2007년도 춘계학술대회A
• /
• pp.608-613
• /
• 2007

Fine pitch microprobe arrays are microneedle-like probes for inspecting the pixel of LCD panel. They are usually made of multilayers of metallic, nonmetallic, or combination of the two. In this study, the microprobe arrays were fabricated using the process applied for MEMS fabrication technology and they consist of BeCu, BeNi, or Si. Their contacting probing force and deflection were measured using the laser equipment. The design requirement are 5gf of a minimum contact force and $150{\mu}m$ of a maximum deflection. A lot of microprobe shape are possible satisfying the requirement. A double cantilever-type microprobe having needles on both ends were applied for this study. Several candidate were chosen using the topology and shape optimization technique subjected to the design requirements. Finite element results and experimental results were compared and both gave good correlation.

• IEIE Transactions on Smart Processing and Computing
• /
• 제5권2호
• /
• pp.143-151
• /
• 2016

This paper presents new prediction methods to improve compression performance of the so-called near-lossless RGB-domain image coder, which is designed to effectively decrease the memory bandwidth of a system-on-chip (SoC) for image processing. First, variable block size (VBS)-based intra prediction is employed to eliminate spatial redundancy for the green (G) component of an input image on a pixel-line basis. Second, inter-color prediction (ICP) using spectral correlation is performed to predict the R and B components from the previously reconstructed G-component image. Experimental results show that the proposed algorithm improves coding efficiency by up to 30% compared with an existing algorithm for natural images, and improves coding efficiency with low computational cost by about 50% for computer graphics (CG) images.

• 전자공학회논문지B
• /
• 제32B권8호
• /
• pp.1091-1098
• /
• 1995

This paper proposes an efficient noiseless encoding method of vector quantization(VQ) index using a dynamic index mapping. Using high interblock correlation, the proposed index mapper transforms an index into a new one with lower entropy. In order to achieve good performance with low computational complexity, we adopt 'the sum of differences in pixel values on the block boundaries' as the cost function for index mapping. Simulation results show that the proposed scheme reduces the average bitrate by 40 - 50 % in ordinary VQ system for image compression. In addition, it is shown that the proposed index mapping method can be also applied to mean-residual VQ system, which allows the reduction of bitrate for VQ index by 20 - 30 %(10 - 20 % reduction in total bitrate). Since the proposed scheme is one for noiseless encoding of VQ index, it provides the same quality of the reconstructed image as the conventional VQ system.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1999년도 하계학술대회 논문집 G
• /
• pp.2941-2943
• /
• 1999

The application of the aerial images are to find the 3-D elevations. Image matching techniques such as Multi-resolution techniques, WCC (Weighted Cross-Correlation), NSSR (Narrow Search Sub-pixel Registration) that we know robustly apply to images which have enough features. But the method is not adaptive in images which have not enough features due to increasing of disparity errors. In this paper, we propose Disparity Interpolation that decrease disparity errors occurring in the area where images have not enough features. By using real aerial images we compare the result from existing image matching techniques to the result from proposed method.

• 원예과학기술지
• /
• 제16권3호
• /
• pp.364-365
• /
• 1998

본 연구는 기존 원예종에 비해 관상가치가 높은 반입종식물이 나타내는 반입현상의 다양한 변화를 측정할 수 있는 보다 정확한 검정방법을 개발코자 실시되었다. Scanning을 통한 컴퓨터 분석을 이용해 Tradescantia 2품종에 대한 전체엽면적 및 반입면적을 측정한 결과 광도가 증가할수록 전체엽면적은 감소하였으며 반입면적은 증가하는 결과를 나타내었다. 음지에서는 공시된 2품종 모두의 엽면적은 증가하였으며 반입면적은 급속히 감소하였다. 또한 위에 언급한 방법과 동일한 수법으로 광도에 따른 반입색차를 측정한 결과 양지에서 가장 밝은 엽색정도를 보였으며 광도가 감소할수록 엽색정도가 짙어졌다. 위의 결과에 대해 엽면적계로 전체 엽면적 및 반입면적을 측정한 값($cm^2$)과 본 연구에서 scanning을 하여 얻은 그래픽파일을 이용한 컴퓨터 분석시의 수치(pixel)간의 상관정도를 구한 결과 매우 높은 상관관계가 있었다. 따라서 컴퓨터그래픽분석을 이용한 엽면적 및 반입면적의 측정법은 매우 정확하며 간편하게 쓰일 수 있을 것으로 추측되었다.

• 대한원격탐사학회:학술대회논문집
• /
• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
• /
• pp.542-545
• /
• 2005

Spaceborne radar interferometry has been widely used to estimate the topography and deformation of the Earth. It is difficult to obtain coherent interferometric SAR pairs especially over coastal areas mainly because of variation of surface conditions. We carried out the experiment using a cross-interferometric pair with a perpendicular baseline of about 1.4 km, a 30 minutes temporal separation and the height sensitivity of about 6 meters. The temporal decorrelation can be reduced by the cross interferometric technique with a 30 minutes temporal separation. Accurate coregistration was performed through resampling of ENVISAT ASAR data to equivalent pixel spacing to the ERS SAR data, because of the differences of the pulse repetition frequency and range sampling rate between the two sensors. Then we estimated range and azimuth offset to a sub-pixel accuracy using image intensity cross correlation. A larger window chip size than a general case was used because it was difficult to distinguish typical features. As range bin increased, the difference of Doppler centroid also increased. It resulted in lower coherence in far range than in near range. Coherences over wetland in near and far range were about 0.8 and 0.5, respectively. The coherence was improved by applying azimuth and range common band filtering, but coherence gap still existed. ERS-ENVISAT cross-interferogram usually lost information in urban area. However, high coherence over a city in this pair was shown, because of less man-made structures than other major cities. Accuracy of the DEM constructed by the ERS-ENVISAT 30-minute pair in a coastal area is to be evaluated.

• 대한한방내과학회지
• /
• 제35권1호
• /
• pp.1-11
• /
• 2014

Objectives : To investigate the effects of Sa-am acupuncture on muscle architecture and elastic properties of the spastic elbow flexor and to evaluate the correlation between clinical findings and parameters of real-time sonoelastography (RTS) in patients with chronic post-stroke hemiparesis. Materials and Methods : Seven patients (five males, two females) with chronic post-stroke hemiparesis were included. Sa-am acupuncture of Ganseunggyeok (肝勝格: LU8 LR4 補, HT8 LR2 瀉) was applied to the unaffected side 3 times a week for 4 weeks. During each acupuncture treatment period, patients were requested to exercise their affected arm, and spasticity and functional recovery outcomes of the affected arm were evaluated before and after Sa-am acupuncture treatment. Clinical outcomes were assessed using motricity index (MI), modified Ashworth scale (MAS), Fugl-Meyer assessment scale (FMA) and modified Barthel index (MBI) for elbow flexor spasticity. RTS images indicate the relative hardness of the examined muscles ranged from red (hard) to purple (soft) for color-scale, and from black (hard) to white (soft) for hue scale. Color and hue histograms of the biceps brachii and brachialis were analyzed using Image J software, and median red, blue, and hue pixel intensity were obtained. Results : MI and FMA score significantly increased and MAS score significantly decreased (p<0.05). F-wave maximal amplitude of affected abductor pollicis brevis significantly decreased (p<0.05). Muscle thickness of affected brachialis significantly increased (p<0.05). Red and green pixel intensity of affected brachialis significantly decreased (p<0.05). Conclusions : Our study revealed that Sa-am acupuncture is effective as a useful and safe treatment for spasticity in chronic post-stroke hemiparesis.

• 한국콘텐츠학회논문지
• /
• 제5권3호
• /
• pp.123-131
• /
• 2005

디지털 해프토닝 방법 중 오차 확산 해프토닝은 다른 해프토닝 방법에 비해 우수한 화질을 보이지만 에지가 흐려지는 단점이 있다. 이러한 단점을 개선하기 위해, 본 논문은 인간의 공간 지각 특성을 이용하여 에지를 강조하는 개선된 오차 확산 해프토닝 방법을 제안한다. 제안한 방법은 인간의 눈이 한 화소의 명암 값이 아니라 국부 평균을 인식한다는 것과 공간적 변화량을 인간이 인식하는 정도를 이용하여 에지 강조 정보량(IEE : information of edge enhancement)을 구한다. 이 값을 양자화기 입력에 더하여 해프톤 영상의 에지를 강조한다. 이때 컬러 성분간의 상관관계를 고려하여 오차 확산 필터의 계수가 적응적으로 변화하는 방법을 적용한다. 컴퓨터 시뮬레이션 결과는 제안한 방법이 기존의 방법에 비해 영상의 에지가 강조되어 시각적으로 선명한 영상을 생성함을 보여주며 에지를 자연스럽게 표현하고 컬러 임펄스나 거짓 등고선과 같은 단점도 줄여줌을 보여준다.

• 한국정보처리학회논문지
• /
• 제7권8호
• /
• pp.2565-2574
• /
• 2000

오차확산법은 연속계조 영상을 중간조 영상으로 생성시 우수한 재현성을 보인다. 그러나 표시오차의 전력스펙트럼 분석에서 경계정보의 재현성이 다소 떨어지는 특성을 보인다. 이를 개선하기 위해 원영상의 현재화소와 로컬 평균간의 차이정보를 이용하는 경계강조 오차확산법을 제안한다. 제안한 기법은 원영상이 현재화소와 로컬 평균과의 차이정보 및 이를 활용하는 필터의 가중치 함수로 구성된다. 첫째, 원영상의 차이정보는 현재 화소와 이의 인접화소(5x5)의 로컬 평균과의 차이이다. 둘째, 필터의 가중치 함수는 차이정보의 크기를 포함하는 함수와 이의 부호로 구성된다. 제안한 기법을 적용한 중간조 영상은 경계가 강조되어 시각적으로 선명한 결과를 보인다. 환상 평균 전력 스펙트럼 밀도를 이용한 표시오차, 경계상관도 및 로컬 평균 일치도의 평가함수로 제안한 경계강조 오차확산법과 기존의 경계강조 오차확산법의 특성을 비교한다.