• 방송공학회논문지
• /
• 제9권2호
• /
• pp.110-118
• /
• 2004

This paper shows that blind deconvolution has only finite solutions when an original image and a point spread function are nonzero over a restricted domain, in other words, an observed image has a compact support. The key of the proof is to use z-transformations and factorizations of polynomials. Then, we propose an algorithm to find all finite solutions under the boundary condition. Finally, we confirm that we can extract all sets of an original image and a point spread function from a degraded image by using our algorithm in numerical examples.

• 대한의용생체공학회:학술대회논문집
• /
• 대한의용생체공학회 1994년도 추계학술대회
• /
• pp.117-120
• /
• 1994

수술 전 간 기능이 저하되어 있는 간암환자의 경우 너무 많은 간 조직을 절제하면 남아있는 조직의 기능만으로는 생존하기 어려울 때가 있다 그러므로 수술전 간 기능의 평가를 정확히 할 수 있고 간절제 후에 잔여세포의 기능을 정확히 측정하는 것은 매우 중요한 의미를 갖게 된다. 현재의 일반적인 간 기능 검사나 Indocyanine 등을 이용하는 방법으로는 수술 후 잔여 간세포의 기능을 예측할 수 없다. 그리하여 본 연구에서는 수학적 deconvolution 방법을 이용하여 Hepatic extraction fraction(HEF)를 구하여 수술 후 잔여 간세포의 기능을 정량적으로 예측할 수 있는 software를 개발하고자 한다. 그리하여 간암 환자의 수술여부 및 절제부위의 크기를 결정할 수 있으며 또한 HEF로 신생아 황달의 원인인 간염과 간담도 폐쇄를 식별할 수 있다.

• 한국멀티미디어학회논문지
• /
• 제17권7호
• /
• pp.838-848
• /
• 2014

In this paper, we conducted a cause analysis on boundary artifacts in image deconvolution. Results of the cause analysis show that boundary artifacts are caused not only by a misuse of boundary conditions but also by no use of the normalized backprojection. Results also showed that the correct use of boundary conditions does not necessarily remove boundary artifacts. Based on these observations, we suggest not to use any specific boundary conditions and to use the normalized backprojector for boundary artifact-free image deconvolution.

• Journal of applied mathematics & informatics
• /
• 제19권1_2호
• /
• pp.151-164
• /
• 2005

The regularized structured total least norm (RSTLN) method finds an approximate solution x and error matrix E to the overdetermined linear system (H + E)x $\approx$ b, preserving structure of H. A new separation scheme by parts of variables for the regularized structured total least norm on blind deconvolution problem is suggested. A method combining the regularized structured total least norm method with a separation by parts of variables can be obtain a better approximated solution and a smaller residual. Computational results for the practical problem with Block Toeplitz with Toeplitz Block structure show the new method ensures more efficiency on image restoration.

• Communications for Statistical Applications and Methods
• /
• 제4권3호
• /
• pp.833-845
• /
• 1997

Fourier expansion is considered for the deconvolution problem of estimating a probability density function when the sample observations are contaminated with random noise. In the log-Fourier method of density estimation for data without noise, the logarithm of the unknown density function is approximated by a trigonometric function, the unknown parameters of which are estimated by maximum likelihood. The log-Fourier density estimation method, which has been considered theoretically by Koo and Chung (1997), is studied for the finite-sample case with noise. Numerical examples using simulated data are given to show the performance of the log-Fourier deconvolution.

• 한국산학기술학회:학술대회논문집
• /
• 한국산학기술학회 2006년도 춘계학술발표논문집
• /
• pp.209-213
• /
• 2006

In this paper describes image enhancement technique using deconvolution processing for ultrasonic nondestructive testing. . When flaws are detected for B-scan or C-scan, blurring effect which is caused by the moving intervals of transducer degrades the quality of images. In addition, acquisited images suffer form speckle noise which is caused by the ultrasonic components reflected from the grain boundary of material [1,2]. The deconvolution technique can restore sharp peak value or clean image from blurring signal or image. This processing is applied to C-scan image obtained from known specimen. Experimental results show that the deconvolution processing contributes to get improved the quality of C-scan images.

• Structural Engineering and Mechanics
• /
• 제21권3호
• /
• pp.237-254
• /
• 2005

This article deals with the reconstruction of an impact force. This requires to take measurements from the impacted structures and then to deconvolve those signals from the impulse response function. More precisely, the purpose of the work described here is to analyse the method of deconvolution and the problems that it implies. Thus, it is highlighted that the associated deconvolution problem depends on the location of the measurement points: it is possible or not to reconstruct the force of impact in function of the location of this point. Then, the role of the antiresonances is linked up with this problem. The singular value decomposition is used to understand these difficulties. Numerical predictions are compared and validated with experiments.

• 한국해양공학회:학술대회논문집
• /
• 한국해양공학회 2001년도 춘계학술대회 논문집
• /
• pp.166-171
• /
• 2001

A digital seismic data acquisition and processing system using a PC has been developed in order to replace the analog data acquisition system of shallow marine seismic survey. An A/D converter that has 12bits of resolution and 225KHz of conversion rate was ued to acquire data, and a data acquisition software was developed as a Windows program which provides convenience of use. Raw data acquired at field has been saved to the hard-disk simultaneously. The signal to noise ratio, vertical and horizontal resolution could be improved by a digital data processing of the raw data. The digital processing of the raw data includss gain recovery, filtering, deconvolution, and muting. With the prediction deconvolution algorithm multiple reflections appearing on the shallow marine seismic section could be removed successfully.

• 한국전자통신학회논문지
• /
• 제7권6호
• /
• pp.1403-1411
• /
• 2012

본 논문에서는 최근 DC 전력케이블에서 큰 이슈가 되고 있는 공간전하(space charge) 문제와 관련하여 공간전하의 비파괴 측정법 중 하나인 펄스정전응력법(PEA method)에 대한 이론적 고찰을 수행하였으며, 이를 바탕으로 직류전압 하에서 고분자 유전체 내에서 공간전하분포를 측정할 수 있는 시스템을 개발하였다. 또한, 보정(deconvolution) 처리를 통해 왜곡된 공간전하 신호에 대한 개선을 실시함으로써 신호의 정확도를 개선하였다.

• Bulletin of the Korean Chemical Society
• /
• 제10권4호
• /
• pp.368-371
• /
• 1989

The constrained, iterative Fourier deconvolution procedure was applied to quantitatively analyze the overlapped bands in the Raman spectra of biomolecules. When applied to Raman spectra of lysozyme and ${\alpha}$-amylase, this procedure resolved the amide Ⅰ band into five component peaks. The relative intensities of the resolved peaks can possibly provide the composition of secondary structure elements in proteins. The deconvolution procedure was also useful in monitoring the small changes in relative intensities of C-S stretching modes due to different conformers of L-methionine in aqueous solutions at different pH values. The implemented procedure is generally applicable to the problem of resolution enhancement of spectroscopic, chromatographic, and electrophoretic data.