WorldWideScience

Sample records for tv-based image restoration

  1. Kernel TV-Based Quotient Image Employing Gabor Analysis and Its Application to Face Recognition

    Science.gov (United States)

    An, Gaoyun; Wu, Jiying; Ruan, Qiuqi

    In order to overcome the drawback of TVQI and to utilize the property of dimensionality increasing techniques, a novel model for Kernel TV-based Quotient Image employing Gabor analysis is proposed and applied to face recognition with only one sample per subject. To deal with illumination outliers, an enhanced TV-based quotient image (ETVQI) model is first adopted. Then for preprocessed images by ETVQI, a bank of Gabor filters is built to extract features at specified scales and orientations. Lastly, KPCA is introduced to extract final high-order and nonlinear features of extracted Gabor features. According to experiments on the CAS-PEAL face database, our model could outperform Gabor-based KPCA, TVQI and Gabor-based TVQI when they face most outliers (illumination, expression, masking etc.).

  2. Smoothing of Fused Spectral Consistent Satellite Images with TV-based Edge Detection

    DEFF Research Database (Denmark)

    Sveinsson, Johannes; Aanæs, Henrik; Benediktsson, Jon Atli

    2007-01-01

    Several widely used methods have been proposed for fusing high resolution panchromatic data and lower resolution multi-channel data. However, many of these methods fail to maintain the spectral consistency of the fused high resolution image, which is of high importance to many of the applications...... based on satellite data. Additionally, most conventional methods are loosely connected to the image forming physics of the satellite image, giving these methods an ad hoc feel. Vesteinsson et al. [1] proposed a method of fusion of satellite images that is based on the properties of imaging physics...... in a statistically meaningful way and was called spectral consistent panshapening (SCP). In this paper we improve this framework for satellite image fusion by introducing a better image prior, via data-dependent image smoothing. The dependency is obtained via total variation edge detection method....

  3. An Iterative Shrinkage Approach to Total-Variation Image Restoration

    CERN Document Server

    Michailovich, Oleg

    2009-01-01

    The problem of restoration of digital images from their degraded measurements plays a central role in a multitude of practically important applications. A particularly challenging instance of this problem occurs in the case when the degradation phenomenon is modeled by an ill-conditioned operator. In such a case, the presence of noise makes it impossible to recover a valuable approximation of the image of interest without using some a priori information about its properties. Such a priori information is essential for image restoration, rendering it stable and robust to noise. Particularly, if the original image is known to be a piecewise smooth function, one of the standard priors used in this case is defined by the Rudin-Osher-Fatemi model, which results in total variation (TV) based image restoration. The current arsenal of algorithms for TV-based image restoration is vast. In the present paper, a different approach to the solution of the problem is proposed based on the method of iterative shrinkage (aka i...

  4. Image restoration scale space

    Science.gov (United States)

    Alvarez, Luis; Mazorra, L.; Santana, F.

    1995-09-01

    We present a study of some image resoration techniques based on partial differential equations. We study separately the denoising problem and the restoration of discontinuities. We analyze the capabilities of the differential operators to restore images. In particular, we analyze a number of models present in the literature, and we present comparative results. Finally, we present a model based in the combination of the anisotropic diffusion of Alvarez, Lions, and Morel and the shock filters of Osher and Rudin.

  5. Adaptive wiener image restoration kernel

    Science.gov (United States)

    Yuan, Ding

    2007-06-05

    A method and device for restoration of electro-optical image data using an adaptive Wiener filter begins with constructing imaging system Optical Transfer Function, and the Fourier Transformations of the noise and the image. A spatial representation of the imaged object is restored by spatial convolution of the image using a Wiener restoration kernel.

  6. A generalized accelerated proximal gradient approach for total-variation-based image restoration.

    Science.gov (United States)

    Zuo, Wangmeng; Lin, Zhouchen

    2011-10-01

    This paper proposes a generalized accelerated proximal gradient (GAPG) approach for solving total variation (TV)-based image restoration problems. The GAPG algorithm generalizes the original APG algorithm by replacing the Lipschitz constant with an appropriate positive-definite matrix, resulting in faster convergence. For TV-based image restoration problems, we further introduce two auxiliary variables that approximate the partial derivatives. Constraints on the variables can easily be imposed without modifying the algorithm much, and the TV regularization can be either isotropic or anisotropic. As compared with the recently developed APG-based methods for TV-based image restoration, i.e., monotone version of the two-step iterative shrinkage/thresholding algorithm (MTwIST) and monotone version of the fast IST algorithm (MFISTA), our GAPG is much simpler as it does not require to solve an image denoising subproblem. Moreover, the convergence rate of O(k(-2)) is maintained by our GAPG, where k is the number of iterations; the cost of each iteration in GAPG is also lower. As a result, in our experiments, our GAPG approach can be much faster than MTwIST and MFISTA. The experiments also verify that our GAPG converges faster than the original APG and MTwIST when they solve identical problems.

  7. Image Restoration with New Technology

    DEFF Research Database (Denmark)

    Bülow-Møller, Anne Marie

    The article examines the role played by the corporate website while a company - Arla - attempted to restore an image tarnished by unethical behaviour. The company's strategy focussed on dialogue: it introduced a large number of authentic employees in their natural role as cook, dairy farmer, etc...... their image as a faceless monopoly with a humanized, personalised version. However, it should also be questioned if, in the long run, it was the image campaign rather than the visible efforts of the company to behave with consideration that brought about the desired change. Keywords: Image restoration......., and made them available to readers as experts providing inspiration and advice, or as writers blogging about the world of company, or as responsible people answering readers' frank questions about their practices in an open forum. It is argued that the electronic platform allowed the company to substitute...

  8. Bayesian image restoration, using configurations

    DEFF Research Database (Denmark)

    Thorarinsdottir, Thordis

    configurations are expressed in terms of the mean normal measure of the random set. These probabilities are used as prior probabilities in a Bayesian image restoration approach. Estimation of the remaining parameters in the model is outlined for salt and pepper noise. The inference in the model is discussed...

  9. Bayesian image restoration, using configurations

    DEFF Research Database (Denmark)

    Thorarinsdottir, Thordis Linda

    2006-01-01

    configurations are expressed in terms of the mean normal measure of the random set. These probabilities are used as prior probabilities in a Bayesian image restoration approach. Estimation of the remaining parameters in the model is outlined for the salt and pepper noise. The inference in the model is discussed...

  10. Image Restoration with New Technology

    DEFF Research Database (Denmark)

    Bülow-Møller, Anne Marie

    The article examines the role played by the corporate website while a company - Arla - attempted to restore an image tarnished by unethical behaviour. The company's strategy focussed on dialogue: it introduced a large number of authentic employees in their natural role as cook, dairy farmer, etc...

  11. Image restoration using spectrum estimation

    Science.gov (United States)

    Na, Ki-Woon; Paik, Joon-Ki

    1994-09-01

    A stochastic approach to image restoration is proposed by using various spectrum estimation techniques. In order to estimate the original image from the knowledge of observed image, the minimum mean square error filter or Wiener filter is known to be optimum in the sense of minimizing the mean square error. The optimality of Wiener filter, however, holds only when the power spectra of the original image and noise are given in addition to the transfer function of the imaging system. In practice, the information of the original image is generally not available. In the present paper additive noise is assumed to be white with known variance and the Wiener filter is implemented using various estimation techniques for the original spectrum. The proposed method shows significant improvement over the conventional methods, such as the Wiener filter using constant signal-to-noise power ratio, particularly for images with low signal-to-noise ratio.

  12. Image Enhancement and Restoration by Image Inpainting

    Directory of Open Access Journals (Sweden)

    Nishant Trivedi

    2014-12-01

    Full Text Available Inpainting is the process of reconstructing lost or deteriorated part of images based on the background information. i. e .it fills the missing or damaged region in an image utilizing spatial information of its neighboring region. Inpainting algorithm have numerous applications. It is helpfully used for restoration of old films and object removal in digital photographs. The main goal of the algorithm is to modify the damaged region in an image in such a way that the inpainted region is undetectable to the ordinary observers who are not familiar with the original image. This proposed work presents image inpainting process for image enhancement and restoration by using structural, texture and exemplar techniques. This paper presents efficient algorithm that combines the advantages of these two approaches. We first note that exemplar-based texture synthesis contains the essential process required to replicate both texture and structure; the success of structure propagation, however, is highly dependent on the order in which the filling proceeds. We propose a best-first algorithm in which the confidence in the synthesized pixel values is propagated in a manner similar to the propagation of information in inpainting. The actual color values are computed using exemplar-based synthesis. Computational efficiency is achieved by a blockbased sampling process.

  13. BAYESIAN IMAGE RESTORATION, USING CONFIGURATIONS

    Directory of Open Access Journals (Sweden)

    Thordis Linda Thorarinsdottir

    2011-05-01

    Full Text Available In this paper, we develop a Bayesian procedure for removing noise from images that can be viewed as noisy realisations of random sets in the plane. The procedure utilises recent advances in configuration theory for noise free random sets, where the probabilities of observing the different boundary configurations are expressed in terms of the mean normal measure of the random set. These probabilities are used as prior probabilities in a Bayesian image restoration approach. Estimation of the remaining parameters in the model is outlined for salt and pepper noise. The inference in the model is discussed in detail for 3 X 3 and 5 X 5 configurations and examples of the performance of the procedure are given.

  14. ℓ0TV: A new method for image restoration in the presence of impulse noise

    KAUST Repository

    Yuan, Ganzhao

    2015-06-02

    Total Variation (TV) is an effective and popular prior model in the field of regularization-based image processing. This paper focuses on TV for image restoration in the presence of impulse noise. This type of noise frequently arises in data acquisition and transmission due to many reasons, e.g. a faulty sensor or analog-to-digital converter errors. Removing this noise is an important task in image restoration. State-of-the-art methods such as Adaptive Outlier Pursuit(AOP), which is based on TV with L02-norm data fidelity, only give sub-optimal performance. In this paper, we propose a new method, called L0T V -PADMM, which solves the TV-based restoration problem with L0-norm data fidelity. To effectively deal with the resulting non-convex nonsmooth optimization problem, we first reformulate it as an equivalent MPEC (Mathematical Program with Equilibrium Constraints), and then solve it using a proximal Alternating Direction Method of Multipliers (PADMM). Our L0TV-PADMM method finds a desirable solution to the original L0-norm optimization problem and is proven to be convergent under mild conditions. We apply L0TV-PADMM to the problems of image denoising and deblurring in the presence of impulse noise. Our extensive experiments demonstrate that L0TV-PADMM outperforms state-of-the-art image restoration methods.

  15. Error image aware content restoration

    Science.gov (United States)

    Choi, Sungwoo; Lee, Moonsik; Jung, Byunghee

    2015-12-01

    As the resolution of TV significantly increased, content consumers have become increasingly sensitive to the subtlest defect in TV contents. This rising standard in quality demanded by consumers has posed a new challenge in today's context where the tape-based process has transitioned to the file-based process: the transition necessitated digitalizing old archives, a process which inevitably produces errors such as disordered pixel blocks, scattered white noise, or totally missing pixels. Unsurprisingly, detecting and fixing such errors require a substantial amount of time and human labor to meet the standard demanded by today's consumers. In this paper, we introduce a novel, automated error restoration algorithm which can be applied to different types of classic errors by utilizing adjacent images while preserving the undamaged parts of an error image as much as possible. We tested our method to error images detected from our quality check system in KBS(Korean Broadcasting System) video archive. We are also implementing the algorithm as a plugin of well-known NLE(Non-linear editing system), which is a familiar tool for quality control agent.

  16. ROV Based Underwater Blurred Image Restoration

    Institute of Scientific and Technical Information of China (English)

    LIU Zhishen; DING Tianfu; WANG Gang

    2003-01-01

    In this paper, we present a method of ROV based image processing to restore underwater blurry images from the theory of light and image transmission in the sea. Computer is used to simulate the maximum detection range of the ROV under different water body conditions. The receiving irradiance of the video camera at different detection ranges is also calculated. The ROV's detection performance under different water body conditions is given by simulation. We restore the underwater blurry images using the Wiener filter based on the simulation. The Wiener filter is shown to be a simple useful method for underwater image restoration in the ROV underwater experiments. We also present examples of restored images of an underwater standard target taken by the video camera in these experiments.

  17. Restoration of multichannel microwave radiometric images

    Science.gov (United States)

    Chin, R. T.; Yeh, C.-L.; Olson, W. S.

    1985-01-01

    A constrained iterative image restoration method is applied to multichannel diffraction-limited imagery. This method is based on the Gerchberg-Papoulis algorithm utilizing incomplete information and partial constraints. The procedure is described using the orthogonal projection operators which project onto two prescribed subspaces iteratively. Its properties and limitations are presented. The effect of noise was investigated and a better understanding of the performance of the algorithm with noisy data has been achieved. The restoration scheme with the selection of appropriate constraints was applied to a practical problem. The 6.6, 10.7, 18, and 21 GHz satellite images obtained by the scanning multichannel microwave radiometer (SMMR), each having different spatial resolution, were restored to a common, high resolution (that of the 37 GHz channels) to demonstrate the effectiveness of the method. Both simulated data and real data were used in this study. The restored multichannel images may be utilized to retrieve rainfall distributions.

  18. Restoration of multichannel microwave radiometric images

    Science.gov (United States)

    Chin, R. T.; Yeh, C.-L.; Olson, W. S.

    1985-01-01

    A constrained iterative image restoration method is applied to multichannel diffraction-limited imagery. This method is based on the Gerchberg-Papoulis algorithm utilizing incomplete information and partial constraints. The procedure is described using the orthogonal projection operators which project onto two prescribed subspaces iteratively. Its properties and limitations are presented. The effect of noise was investigated and a better understanding of the performance of the algorithm with noisy data has been achieved. The restoration scheme with the selection of appropriate constraints was applied to a practical problem. The 6.6, 10.7, 18, and 21 GHz satellite images obtained by the scanning multichannel microwave radiometer (SMMR), each having different spatial resolution, were restored to a common, high resolution (that of the 37 GHz channels) to demonstrate the effectiveness of the method. Both simulated data and real data were used in this study. The restored multichannel images may be utilized to retrieve rainfall distributions.

  19. Image Restoration After Pixel Binning in Image Sensors

    Institute of Scientific and Technical Information of China (English)

    LI Hao; ZHANG Hui; GUO Xiaolian; HU Guangshu

    2009-01-01

    A method was developed to restore degraded images to some extent after the pixel binning pro-cess in image sensors to improve the resolution. A pixel binning model was used to approximate the original un-binned image. Then, the least squares error criterion was used as a constraint to reconstruct the re-stored pixel values from the binning model. The technique achieves about a one-decibel increase in the peak signal-to-noise ratio compared with the odginal estimated image. The technique has good detail pre-servation performance as well as low computation load. Thus, this restoration technique provides valuable improvements in practical, real time image processing.

  20. Spatially Adaptive Intensity Bounds for Image Restoration

    Directory of Open Access Journals (Sweden)

    Kaaren L. May

    2003-11-01

    Full Text Available Spatially-adaptive intensity bounds on the image estimate are shown to be an effective means of regularising the ill-posed image restoration problem. For blind restoration, the local intensity constraints also help to further define the solution, thereby reducing the number of multiple solutions and local minima. The bounds are defined in terms of the local statistics of the image estimate and a control parameter which determines the scale of the bounds. Guidelines for choosing this parameter are developed in the context of classical (nonblind image restoration. The intensity bounds are applied by means of the gradient projection method, and conditions for convergence are derived when the bounds are refined using the current image estimate. Based on this method, a new alternating constrained minimisation approach is proposed for blind image restoration. On the basis of the experimental results provided, it is found that local intensity bounds offer a simple, flexible method of constraining both the nonblind and blind restoration problems.

  1. Image Restoration And Resolution Enhancement

    Science.gov (United States)

    Byrne, Charles L.; Fitzgerald, Raymond M.

    1983-09-01

    We consider mathematical algorithms for the restoration of object information from finitely many measurements of the object's spectrum, with particular emphasis on the development of linear and nonlinear non-iterative methods that can incorporate prior information about object extent and shape. The linear method presented here generalizes the minimum energy bandlimited extrapolation procedure, which is the closed form limit of Gerchberg-Papoulis iteration in this case. The nonlinear method generalizes the maximum entropy method (MEM) of Burg.

  2. Matrix Krylov subspace methods for image restoration

    Directory of Open Access Journals (Sweden)

    khalide jbilou

    2015-09-01

    Full Text Available In the present paper, we consider some matrix Krylov subspace methods for solving ill-posed linear matrix equations and in those problems coming from the restoration of blurred and noisy images. Applying the well known Tikhonov regularization procedure leads to a Sylvester matrix equation depending the Tikhonov regularized parameter. We apply the matrix versions of the well known Krylov subspace methods, namely the Least Squared (LSQR and the conjugate gradient (CG methods to get approximate solutions representing the restored images. Some numerical tests are presented to show the effectiveness of the proposed methods.

  3. Restoration for Noise Removal in Quantum Images

    Science.gov (United States)

    Liu, Kai; Zhang, Yi; Lu, Kai; Wang, Xiaoping

    2017-09-01

    Quantum computation has become increasingly attractive in the past few decades due to its extraordinary performance. As a result, some studies focusing on image representation and processing via quantum mechanics have been done. However, few of them have considered the quantum operations for images restoration. To address this problem, three noise removal algorithms are proposed in this paper based on the novel enhanced quantum representation model, oriented to two kinds of noise pollution (Salt-and-Pepper noise and Gaussian noise). For the first algorithm Q-Mean, it is designed to remove the Salt-and-Pepper noise. The noise points are extracted through comparisons with the adjacent pixel values, after which the restoration operation is finished by mean filtering. As for the second method Q-Gauss, a special mask is applied to weaken the Gaussian noise pollution. The third algorithm Q-Adapt is effective for the source image containing unknown noise. The type of noise can be judged through the quantum statistic operations for the color value of the whole image, and then different noise removal algorithms are used to conduct image restoration respectively. Performance analysis reveals that our methods can offer high restoration quality and achieve significant speedup through inherent parallelism of quantum computation.

  4. Robust Image Restoration for Motion Blur of Image Sensors.

    Science.gov (United States)

    Yang, Fasheng; Huang, Yongmei; Luo, Yihan; Li, Lixing; Li, Hongwei

    2016-06-09

    Blind image restoration algorithms for motion blur have been deeply researched in the past years. Although great progress has been made, blurred images containing large blur and rich, small details still cannot be restored perfectly. To deal with these problems, we present a robust image restoration algorithm for motion blur of general image sensors in this paper. Firstly, we propose a self-adaptive structure extraction method based on the total variation (TV) to separate the reliable structures from textures and small details of a blurred image which may damage the kernel estimation and interim latent image restoration. Secondly, we combine the reliable structures with priors of the blur kernel, such as sparsity and continuity, by a two-step method with which noise can be removed during iterations of the estimation to improve the precision of the estimated blur kernel. Finally, we use a MR-based Wiener filter as the non-blind deconvolution algorithm to restore the final latent image. Experimental results demonstrate that our algorithm can restore large blur images with rich, small details effectively.

  5. Radiopacity of restorative materials using digital images.

    Science.gov (United States)

    Salzedas, Leda Maria Pescinini; Louzada, Mário Jefferson Quirino; de Oliveira Filho, Antonio Braz

    2006-04-01

    The radiopacity of esthetic restorative materials has been established as an important requirement, improving the radiographic diagnosis. The aim of this study was to evaluate the radiopacity of six restorative materials using a direct digital image system, comparing them to the dental tissues (enamel-dentin), expressed as equivalent thickness of aluminum (millimeters of aluminum). Five specimens of each material were made. Three 2-mm thick longitudinal sections were cut from an intact extracted permanent molar tooth (including enamel and dentin). An aluminum step wedge with 9 steps was used. The samples of different materials were placed on a phosphor plate together with a tooth section, aluminum step wedge and metal code letter, and were exposed using a dental x-ray unit. Five measurements of radiographic density were obtained from each image of each item assessed (restorative material, enamel, dentin, each step of the aluminum step wedge) and the mean of these values was calculated. Radiopacity values were subsequently calculated as equivalents of aluminum thickness. Analysis of variance (ANOVA) indicated significant differences in radiopacity values among the materials (Pcomposite restorations it is important that the restorative material to be used has enough radiopacity, in order to be easily distinguished from the tooth structure in the radiographic image. Knowledge on the radiopacity of different materials helps professionals to select the most suitable material, along with other properties such as biocompatibility, adhesion and esthetic.

  6. Ghost suppression in image restoration filtering

    Science.gov (United States)

    Riemer, T. E.; Mcgillem, C. D.

    1975-01-01

    An optimum image restoration filter is described in which provision is made to constrain the spatial extent of the restoration function, the noise level of the filter output and the rate of falloff of the composite system point-spread away from the origin. Experimental results show that sidelobes on the composite system point-spread function produce ghosts in the restored image near discontinuities in intensity level. By redetermining the filter using a penalty function that is zero over the main lobe of the composite point-spread function of the optimum filter and nonzero where the point-spread function departs from a smoothly decaying function in the sidelobe region, a great reduction in sidelobe level is obtained. Almost no loss in resolving power of the composite system results from this procedure. By iteratively carrying out the same procedure even further reductions in sidelobe level are obtained. Examples of original and iterated restoration functions are shown along with their effects on a test image.

  7. A Survey on Various Image Inpainting Techniques to Restore Image

    Directory of Open Access Journals (Sweden)

    Rajul Suthar,

    2014-02-01

    Full Text Available Image Inpainting or Image Restore is technique which is used to recover the damaged image and to fill the regions which are missing in original image in visually plausible way. Inpainting, the technique of modifying an image in an invisible form, it is art which is used from the early year. Applications of this technique include rebuilding of damaged photographs& films, removal of superimposed text, removal/replacement of unwanted objects, red eye correction, image coding. The main goal of the Inpainting is to change the damaged region in an image. In this paper we provide a review of different techniques used for image Inpainting. We discuss different inpainting techniques like Exemplar based image inpainting, PDE based image inpainting, texture synthesis based image inpainting, structural inpainting and textural inpainting.

  8. A Variational Bayesian Approach to Multiframe Image Restoration.

    Science.gov (United States)

    Sonogashira, Motoharu; Funatomi, Takuya; Iiyama, Masaaki; Minoh, Michihiko

    2017-03-06

    Image restoration is a fundamental problem in the field of image processing. The key objective of image restoration is to recover clean images from images degraded by noise and blur. Recently, a family of new statistical techniques called variational Bayes (VB) has been introduced to image restoration, which enables us to automatically tune parameters that control restoration. While information from one image is often insufficient for high-quality restoration, however, current state-of-theart methods of image restoration via VB approaches use only a single degraded image to recover a clean image. In this paper, we propose a novel method of multiframe image restoration via a VB approach, which can achieve higher image quality while tuning parameters automatically. Given multiple degraded images, this method jointly estimates a clean image and other parameters, including an image warping parameter introduced for the use of multiple images, through Bayesian inference that we enable by making full use of VB techniques. Through various experiments, we demonstrate the effectiveness of our multiframe method by comparing it with single-frame one, and also show the advantages of our VB approach over non-VB approaches.

  9. IMAGE RESTORATION: DESIGN OF NON-LINEAR FILTER (LR

    Directory of Open Access Journals (Sweden)

    Shenbagarajan Anantharajan

    2012-11-01

    Full Text Available In this proposed method, various types of noise models are subjected to an image and apply the nonlinear filter to reconstruct the original image from degraded image. Image restoration is a technique to attempt of reconstructs the original image by using a degraded phenomenon. In this paper the Lucy-Richardson filter is reconstruct the degraded image which closely resembles the original image. This paper deals with the various noise models and nonlinear filter. Objective of this paper is to study the various noise models and restoration filters in depth at restoration area.

  10. Effective Image Restorations Using a Novel Spatial Adaptive Prior

    Directory of Open Access Journals (Sweden)

    Limin Luo

    2010-01-01

    Full Text Available Bayesian or Maximum a posteriori (MAP approaches can effectively overcome the ill-posed problems of image restoration or deconvolution through incorporating a priori image information. Many restoration methods, such as nonquadratic prior Bayesian restoration and total variation regularization, have been proposed with edge-preserving and noise-removing properties. However, these methods are often inefficient in restoring continuous variation region and suppressing block artifacts. To handle this, this paper proposes a Bayesian restoration approach with a novel spatial adaptive (SA prior. Through selectively and adaptively incorporating the nonlocal image information into the SA prior model, the proposed method effectively suppress the negative disturbance from irrelevant neighbor pixels, and utilizes the positive regularization from the relevant ones. A two-step restoration algorithm for the proposed approach is also given. Comparative experimentation and analysis demonstrate that, bearing high-quality edge-preserving and noise-removing properties, the proposed restoration also has good deblocking property.

  11. Efficient blind image restoration using discrete periodic radon transform.

    Science.gov (United States)

    Lun, Daniel P K; Chan, Tommy C L; Hsung, Tai-Chiu; Feng, David Dagan; Chan, Yuk-Hee

    2004-02-01

    Restoring an image from its convolution with an unknown blur function is a well-known ill-posed problem in image processing. Many approaches have been proposed to solve the problem and they have shown to have good performance in identifying the blur function and restoring the original image. However, in actual implementation, various problems incurred due to the large data size and long computational time of these approaches are undesirable even with the current computing machines. In this paper, an efficient algorithm is proposed for blind image restoration based on the discrete periodic Radon transform (DPRT). With DPRT, the original two-dimensional blind image restoration problem is converted into one-dimensional ones, which greatly reduces the memory size and computational time required. Experimental results show that the resulting approach is faster in almost an order of magnitude as compared with the traditional approach, while the quality of the restored image is similar.

  12. Constrained optimization for image restoration using nonlinear programming

    Science.gov (United States)

    Yeh, C.-L.; Chin, R. T.

    1985-01-01

    The constrained optimization problem for image restoration, utilizing incomplete information and partial constraints, is formulated using nonlinear proramming techniques. This method restores a distorted image by optimizing a chosen object function subject to available constraints. The penalty function method of nonlinear programming is used. Both linear or nonlinear object function, and linear or nonlinear constraint functions can be incorporated in the formulation. This formulation provides a generalized approach to solve constrained optimization problems for image restoration. Experiments using this scheme have been performed. The results are compared with those obtained from other restoration methods and the comparative study is presented.

  13. Image Restoration Technology Based on Discrete Neural network

    Directory of Open Access Journals (Sweden)

    Zhou Duoying

    2015-01-01

    Full Text Available With the development of computer science and technology, the development of artificial intelligence advances rapidly in the field of image restoration. Based on the MATLAB platform, this paper constructs a kind of image restoration technology of artificial intelligence based on the discrete neural network and feedforward network, and carries out simulation and contrast of the restoration process by the use of the bionic algorithm. Through the application of simulation restoration technology, this paper verifies that the discrete neural network has a good convergence and identification capability in the image restoration technology with a better effect than that of the feedforward network. The restoration technology based on the discrete neural network can provide a reliable mathematical model for this field.

  14. Joint Multi-Focus Fusion and Bayer ImageRestoration

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    In this paper, a joint multifocus image fusion and Bayer pattern image restoration algorithm for raw images of single-sensor colorimaging devices is proposed. Different from traditional fusion schemes, the raw Bayer pattern images are fused before colorrestoration. Therefore, the Bayer image restoration operation is only performed one time. Thus, the proposed algorithm is moreefficient than traditional fusion schemes. In detail, a clarity measurement of Bayer pattern image is defined for raw Bayer patternimages, and the fusion operator is performed on superpixels which provide powerful grouping cues of local image feature. Theraw images are merged with refined weight map to get the fused Bayer pattern image, which is restored by the demosaicingalgorithm to get the full resolution color image. Experimental results demonstrate that the proposed algorithm can obtain betterfused results with more natural appearance and fewer artifacts than the traditional algorithms.

  15. Restoration of motion-blurred image based on border deformation detection: a traffic sign restoration model.

    Directory of Open Access Journals (Sweden)

    Yiliang Zeng

    Full Text Available Due to the rapid development of motor vehicle Driver Assistance Systems (DAS, the safety problems associated with automatic driving have become a hot issue in Intelligent Transportation. The traffic sign is one of the most important tools used to reinforce traffic rules. However, traffic sign image degradation based on computer vision is unavoidable during the vehicle movement process. In order to quickly and accurately recognize traffic signs in motion-blurred images in DAS, a new image restoration algorithm based on border deformation detection in the spatial domain is proposed in this paper. The border of a traffic sign is extracted using color information, and then the width of the border is measured in all directions. According to the width measured and the corresponding direction, both the motion direction and scale of the image can be confirmed, and this information can be used to restore the motion-blurred image. Finally, a gray mean grads (GMG ratio is presented to evaluate the image restoration quality. Compared to the traditional restoration approach which is based on the blind deconvolution method and Lucy-Richardson method, our method can greatly restore motion blurred images and improve the correct recognition rate. Our experiments show that the proposed method is able to restore traffic sign information accurately and efficiently.

  16. Super-resolution Restoration of Remote-sensing Images

    Institute of Scientific and Technical Information of China (English)

    LIU Yang-yang; JIN Wei-qi; SU Bing-hua; CHEN Hua; ZHANG Nan

    2006-01-01

    A novel image restoration scheme, which is super-resolution image restoration algorithm Poisson-maximum-afterword-probability based on Markvo constraint (MPMAP) combined with evaluating image detail parameter D, has been proposed. The advantage of super-resolution algorithm MPMAP incorporated with parameter D lies in the fact that super-resolution algorithm MPMAP model is discrete, which is in accordance with remote-sensing imaging model, and the algorithm MPMAP is proved applicable to linear and non-linear imaging models with a unique solution when noise is not severe. According to simulation experiments for practical images, super-resolution algorithm MPMAP can retain image details better than most of traditional restoration methods; at the same time, the proposed parameter D can help to identify real point spread function (PSF) value of degradation process. Processing result of practical remote-sensing images by MPMAP combined with parameter D are given, it illustrates that MPMAP restoration scheme combined PSF estimation has a better restoration result than that of Photoshop processing, based on the same original images. It is proved that the proposed scheme is helpful to offset the lack of resolution of the original remote-sensing images and has its extensive application foreground.

  17. Effects of vibration measurement error on remote sensing image restoration

    Science.gov (United States)

    Sun, Xuan; Wei, Zhang; Zhi, Xiyang

    2016-10-01

    Satellite vibrations would lead to image motion blur. Since the vibration isolators cannot fully suppress the influence of vibrations, image restoration methods are usually adopted, and the vibration characteristics of imaging system are usually required as algorithm inputs for better restoration results, making the vibration measurement error strongly connected to the final outcome. If the measurement error surpass a certain range, the restoration may not be implemented successfully. Therefore it is important to test the applicable scope of restoration algorithms and control the vibrations within the range, on the other hand, if the algorithm is robust, then the requirements for both vibration isolator and vibration detector can be lowered and thus less financial cost is needed. In this paper, vibration-induced degradation is first analyzed, based on which the effects of measurement error on image restoration are further analyzed. The vibration-induced degradation is simulated using high resolution satellite images and then the applicable working condition of typical restoration algorithms are tested with simulation experiments accordingly. The research carried out in this paper provides a valuable reference for future satellite design which plan to implement restoration algorithms.

  18. Color Restoration of Monochrome Image Formatted by Y800

    National Research Council Canada - National Science Library

    Jun Luo; Rui Su; Ying Chen

    2013-01-01

    ...) directly, we design a Bayer mode color filter array start with specific pixels to satisfy the imaging condition and then we use bilinear interpolation algorithm to restore the color of original...

  19. Image and video restorations via nonlocal kernel regression.

    Science.gov (United States)

    Zhang, Haichao; Yang, Jianchao; Zhang, Yanning; Huang, Thomas S

    2013-06-01

    A nonlocal kernel regression (NL-KR) model is presented in this paper for various image and video restoration tasks. The proposed method exploits both the nonlocal self-similarity and local structural regularity properties in natural images. The nonlocal self-similarity is based on the observation that image patches tend to repeat themselves in natural images and videos, and the local structural regularity observes that image patches have regular structures where accurate estimation of pixel values via regression is possible. By unifying both properties explicitly, the proposed NL-KR framework is more robust in image estimation, and the algorithm is applicable to various image and video restoration tasks. In this paper, we apply the proposed model to image and video denoising, deblurring, and superresolution reconstruction. Extensive experimental results on both single images and realistic video sequences demonstrate that the proposed framework performs favorably with previous works both qualitatively and quantitatively.

  20. Adaptive Image Restoration and Segmentation Method Using Different Neighborhood Sizes

    Directory of Open Access Journals (Sweden)

    Chengcheng Li

    2003-04-01

    Full Text Available The image restoration methods based on the Bayesian's framework and Markov random fields (MRF have been widely used in the image-processing field. The basic idea of all these methods is to use calculus of variation and mathematical statistics to average or estimate a pixel value by the values of its neighbors. After applying this averaging process to the whole image a number of times, the noisy pixels, which are abnormal values, are filtered out. Based on the Tea-trade model, which states that the closer the neighbor, more contribution it makes, almost all of these methods use only the nearest four neighbors for calculation. In our previous research [1, 2], we extended the research on CLRS (image restoration and segmentation by using competitive learning algorithm to enlarge the neighborhood size. The results showed that the longer neighborhood range could improve or worsen the restoration results. We also found that the autocorrelation coefficient was an important factor to determine the proper neighborhood size. We then further realized that the computational complexity increased dramatically along with the enlargement of the neighborhood size. This paper is to further the previous research and to discuss the tradeoff between the computational complexity and the restoration improvement by using longer neighborhood range. We used a couple of methods to construct the synthetic images with the exact correlation coefficients we want and to determine the corresponding neighborhood size. We constructed an image with a range of correlation coefficients by blending some synthetic images. Then an adaptive method to find the correlation coefficients of this image was constructed. We restored the image by applying different neighborhood CLRS algorithm to different parts of the image according to its correlation coefficient. Finally, we applied this adaptive method to some real-world images to get improved restoration results than by using single

  1. Scattering removal for finger-vein image restoration.

    Science.gov (United States)

    Yang, Jinfeng; Zhang, Ben; Shi, Yihua

    2012-01-01

    Finger-vein recognition has received increased attention recently. However, the finger-vein images are always captured in poor quality. This certainly makes finger-vein feature representation unreliable, and further impairs the accuracy of finger-vein recognition. In this paper, we first give an analysis of the intrinsic factors causing finger-vein image degradation, and then propose a simple but effective image restoration method based on scattering removal. To give a proper description of finger-vein image degradation, a biological optical model (BOM) specific to finger-vein imaging is proposed according to the principle of light propagation in biological tissues. Based on BOM, the light scattering component is sensibly estimated and properly removed for finger-vein image restoration. Finally, experimental results demonstrate that the proposed method is powerful in enhancing the finger-vein image contrast and in improving the finger-vein image matching accuracy.

  2. Accelerated Edge-Preserving Image Restoration Without Boundary Artifacts

    OpenAIRE

    Matakos, Antonios; Ramani, Sathish; Fessler, Jeffrey A.

    2013-01-01

    To reduce blur in noisy images, regularized image restoration methods have been proposed that use non-quadratic regularizers (like l1 regularization or total-variation) that suppress noise while preserving edges in the image. Most of these methods assume a circulant blur (periodic convolution with a blurring kernel) that can lead to wraparound artifacts along the boundaries of the image due to the implied periodicity of the circulant model. Using a non-circulant model could prevent these arti...

  3. A Good Image Model Eases Restoration

    Science.gov (United States)

    2002-02-06

    algorithms, and various classical as well as unexpected new applications of the BV ( bounded variation ) image model, first introduced into image processing by Rudin, Osher, and Fatemi in 1992 Physica D, 60:259-268.

  4. Image restoration by minimizing zero norm of wavelet frame coefficients

    Science.gov (United States)

    Bao, Chenglong; Dong, Bin; Hou, Likun; Shen, Zuowei; Zhang, Xiaoqun; Zhang, Xue

    2016-11-01

    In this paper, we propose two algorithms, namely the extrapolated proximal iterative hard thresholding (EPIHT) algorithm and the EPIHT algorithm with line-search, for solving the {{\\ell }}0-norm regularized wavelet frame balanced approach for image restoration. Under the theoretical framework of Kurdyka-Łojasiewicz property, we show that the sequences generated by the two algorithms converge to a local minimizer with linear convergence rate. Moreover, extensive numerical experiments on sparse signal reconstruction and wavelet frame based image restoration problems including CT reconstruction, image deblur, demonstrate the improvement of {{\\ell }}0-norm based regularization models over some prevailing ones, as well as the computational efficiency of the proposed algorithms.

  5. The Restoration of Textured Images Using Fractional-Order Regularization

    Directory of Open Access Journals (Sweden)

    Ying Fu

    2014-01-01

    Full Text Available Image restoration problem is ill-posed, so most image restoration algorithms exploit sparse prior in gradient domain to regularize it to yield high-quality results, reconstructing an image with piecewise smooth characteristics. While sparse gradient prior has good performance in noise removal and edge preservation, it also tends to remove midfrequency component such as texture. In this paper, we introduce the sparse prior in fractional-order gradient domain as texture-preserving strategy to restore textured images degraded by blur and/or noise. And we solve the unknown variables in the proposed model using method based on half-quadratic splitting by minimizing the nonconvex energy functional. Numerical experiments show our algorithm's robust outperformance.

  6. Hugh Grant's Image Restoration Discourse: An Actor Apologizes.

    Science.gov (United States)

    Benoit, William L.

    1997-01-01

    Examines the strategies used by actor Hugh Grant (in his appearances on talk shows) to help restore his reputation after he was arrested for lewd behavior with a prostitute. Uses this case as a springboard to contrast entertainment image repair with political and corporate image repair, arguing that important situational differences can be…

  7. The Tonya Harding Controversy: An Analysis of Image Restoration Strategies.

    Science.gov (United States)

    Benoit, William L.; Hanczor, Robert S.

    1994-01-01

    Analyzes Tonya Harding's defense of her image in "Eye to Eye with Connie Chung," applying the theory of image restoration discourse. Finds that the principal strategies employed in her behalf were bolstering, denial, and attacking her accuser, but that these strategies were not developed very effectively in this instance. (SR)

  8. Study of Image Processing, Enhancement and Restoration

    Directory of Open Access Journals (Sweden)

    Bhausaheb Shivajirao Shinde

    2011-11-01

    Full Text Available Digital image processing is a means by which the valuable information in observed raw image data can be revealed. A web-based image processing pipeline was created under the ambitious educational program Venus Transit 2004 (VT-2004. The active participants in the VT-2004 can apply the basic processing methods to the images obtained by their amateur telescopes and/or they can process an image observed at any observatory involved in the project. The processed result image is displayed immediately on the display. Above that all participants can follow the distance Sun-Venus centers computation performed at the professional observatory in the real time. There is a possibility to submit an image from their own observation into the database. It will be used for the distance Earth-Sun computation.

  9. Sparse representation for color image restoration.

    Science.gov (United States)

    Mairal, Julien; Elad, Michael; Sapiro, Guillermo

    2008-01-01

    Sparse representations of signals have drawn considerable interest in recent years. The assumption that natural signals, such as images, admit a sparse decomposition over a redundant dictionary leads to efficient algorithms for handling such sources of data. In particular, the design of well adapted dictionaries for images has been a major challenge. The K-SVD has been recently proposed for this task and shown to perform very well for various grayscale image processing tasks. In this paper, we address the problem of learning dictionaries for color images and extend the K-SVD-based grayscale image denoising algorithm that appears in. This work puts forward ways for handling nonhomogeneous noise and missing information, paving the way to state-of-the-art results in applications such as color image denoising, demosaicing, and inpainting, as demonstrated in this paper.

  10. Full Restoration of Visual Encrypted Color Images

    CERN Document Server

    Persson, Simeon

    2011-01-01

    While strictly black and white images have been the basis for visual cryptography, there has been a lack of an easily implemented format for colour images. This paper establishes a simple, yet secure way of implementing visual cryptography with colour, assuming a binary data representation.

  11. Scattering Removal for Finger-Vein Image Restoration

    OpenAIRE

    Jinfeng Yang; Ben Zhang; Yihua Shi

    2012-01-01

    Finger-vein recognition has received increased attention recently. However, the finger-vein images are always captured in poor quality. This certainly makes finger-vein feature representation unreliable, and further impairs the accuracy of finger-vein recognition. In this paper, we first give an analysis of the intrinsic factors causing finger-vein image degradation, and then propose a simple but effective image restoration method based on scattering removal. To give a proper description of f...

  12. Nonlocal Mumford-Shah regularizers for color image restoration.

    Science.gov (United States)

    Jung, Miyoun; Bresson, Xavier; Chan, Tony F; Vese, Luminita A

    2011-06-01

    We propose here a class of restoration algorithms for color images, based upon the Mumford-Shah (MS) model and nonlocal image information. The Ambrosio-Tortorelli and Shah elliptic approximations are defined to work in a small local neighborhood, which are sufficient to denoise smooth regions with sharp boundaries. However, texture is nonlocal in nature and requires semilocal/non-local information for efficient image denoising and restoration. Inspired from recent works (nonlocal means of Buades, Coll, Morel, and nonlocal total variation of Gilboa, Osher), we extend the local Ambrosio-Tortorelli and Shah approximations to MS functional (MS) to novel nonlocal formulations, for better restoration of fine structures and texture. We present several applications of the proposed nonlocal MS regularizers in image processing such as color image denoising, color image deblurring in the presence of Gaussian or impulse noise, color image inpainting, color image super-resolution, and color filter array demosaicing. In all the applications, the proposed nonlocal regularizers produce superior results over the local ones, especially in image inpainting with large missing regions. We also prove several characterizations of minimizers based upon dual norm formulations.

  13. Alternating Krylov subspace image restoration methods

    National Research Council Canada - National Science Library

    Abad, J.O; Morigi, S; Reichel, L; Sgallari, F

    2012-01-01

    ... of the Krylov subspace used. However, our solution methods, suitably modified, also can be applied when no bound for the norm of η δ is known. We determine an approximation of the desired image u ˆ by so...

  14. Bregmanized Domain Decomposition for Image Restoration

    KAUST Repository

    Langer, Andreas

    2012-05-22

    Computational problems of large-scale data are gaining attention recently due to better hardware and hence, higher dimensionality of images and data sets acquired in applications. In the last couple of years non-smooth minimization problems such as total variation minimization became increasingly important for the solution of these tasks. While being favorable due to the improved enhancement of images compared to smooth imaging approaches, non-smooth minimization problems typically scale badly with the dimension of the data. Hence, for large imaging problems solved by total variation minimization domain decomposition algorithms have been proposed, aiming to split one large problem into N > 1 smaller problems which can be solved on parallel CPUs. The N subproblems constitute constrained minimization problems, where the constraint enforces the support of the minimizer to be the respective subdomain. In this paper we discuss a fast computational algorithm to solve domain decomposition for total variation minimization. In particular, we accelerate the computation of the subproblems by nested Bregman iterations. We propose a Bregmanized Operator Splitting-Split Bregman (BOS-SB) algorithm, which enforces the restriction onto the respective subdomain by a Bregman iteration that is subsequently solved by a Split Bregman strategy. The computational performance of this new approach is discussed for its application to image inpainting and image deblurring. It turns out that the proposed new solution technique is up to three times faster than the iterative algorithm currently used in domain decomposition methods for total variation minimization. © Springer Science+Business Media, LLC 2012.

  15. Restoration of uneven illumination in light sheet microscopy images.

    Science.gov (United States)

    Uddin, Mohammad Shorif; Lee, Hwee Kuan; Preibisch, Stephan; Tomancak, Pavel

    2011-08-01

    Light microscopy images suffer from poor contrast due to light absorption and scattering by the media. The resulting decay in contrast varies exponentially across the image along the incident light path. Classical space invariant deconvolution approaches, while very effective in deblurring, are not designed for the restoration of uneven illumination in microscopy images. In this article, we present a modified radiative transfer theory approach to solve the contrast degradation problem of light sheet microscopy (LSM) images. We confirmed the effectiveness of our approach through simulation as well as real LSM images.

  16. Digital image restoration based on pixel simultaneous detection probabilities

    CERN Document Server

    Grabskii, V

    2008-01-01

    Here an image restoration on the basis of pixel simultaneous detection probabilities (PSDP) is proposed. These probabilities can be precisely determined by means of correlations measurement [NIMA 586 (2008) 314-326]. The proposed image restoration is based on the solution of matrix equation. Non-zero elements of Toeplitz block matrix with ones on the main diagonal, is determined using PSDP. The number of non zero descending diagonals depends on the detector construction and is not always smaller than 8. To solve the matrix equation, the Gaussian elimination algorithm is used. The proposed restoration algorithm is studied by means of the simulated images (with and without additive noise using PSDP for General Electric Senographe 2000D mammography device detector) and a small area (160x160 pixels) of real images acquired by the above mentioned device. The estimation errors of PSDP and the additive noise magnitude permits to restore images with the precision better than 2% for the above mentioned detector. The a...

  17. PIZZARO: Forensic analysis and restoration of image and video data.

    Science.gov (United States)

    Kamenicky, Jan; Bartos, Michal; Flusser, Jan; Mahdian, Babak; Kotera, Jan; Novozamsky, Adam; Saic, Stanislav; Sroubek, Filip; Sorel, Michal; Zita, Ales; Zitova, Barbara; Sima, Zdenek; Svarc, Petr; Horinek, Jan

    2016-07-01

    This paper introduces a set of methods for image and video forensic analysis. They were designed to help to assess image and video credibility and origin and to restore and increase image quality by diminishing unwanted blur, noise, and other possible artifacts. The motivation came from the best practices used in the criminal investigation utilizing images and/or videos. The determination of the image source, the verification of the image content, and image restoration were identified as the most important issues of which automation can facilitate criminalists work. Novel theoretical results complemented with existing approaches (LCD re-capture detection and denoising) were implemented in the PIZZARO software tool, which consists of the image processing functionality as well as of reporting and archiving functions to ensure the repeatability of image analysis procedures and thus fulfills formal aspects of the image/video analysis work. Comparison of new proposed methods with the state of the art approaches is shown. Real use cases are presented, which illustrate the functionality of the developed methods and demonstrate their applicability in different situations. The use cases as well as the method design were solved in tight cooperation of scientists from the Institute of Criminalistics, National Drug Headquarters of the Criminal Police and Investigation Service of the Police of the Czech Republic, and image processing experts from the Czech Academy of Sciences.

  18. Restoration of images possessing a finite Fourier series.

    Science.gov (United States)

    Montgomery, W D

    1982-02-01

    A standard matrix-inversion method is applied to a problem of image restoration that commonly occurs. The relation of this method to the more powerful methods using von Neumann's alternating-projection theorem or the prolate-spheroidal wave functions is indicated.

  19. Restoration algorithms for imaging through atmospheric turbulence

    Science.gov (United States)

    2017-02-18

    imaging based super-resolution algorithm, as well as our current work on the simplification of the Fried kernel for deconvolution purposes. 22...imagemagick library2) and saved as individual PNG sequences. Since the Matlab R© software is widely used by the community, we also provide each...sequence using the GIMP3 software (this procedure is summarized in Figure 2). The dynamic sequences are also provided with their respective 1https

  20. Image Restoration Using the Damped Richardson-Lucy Iteration

    Science.gov (United States)

    White, R. L.

    The most widely used image restoration technique for optical astronomical data is the Richardson-Lucy (RL) iteration. The RL method is well-suited to optical and ultraviolet because it converges to the maximum likelihood solution for Poisson statistics in the data, which is appropriate for astronomical images taken with CCD or photon-counting detectors. Images restored using the RL iteration have good good photometric linearity and can be used for quantitative analysis, and typical RL restorations require a manageable amount of computer time. Despite its advantages, the RL method has some serious shortcomings. Noise amplification is a problem, as for all maximum likelihood techniques. If one performs many RL iterations on an image containing an extended object such as a galaxy, the extended emission develops a ``speckled'' appearance. The speckles are the result of fitting the noise in the data too closely. The only limit on the amount of noise amplification in the RL method is the requirement that the image not become negative. The usual practical approach to limiting noise amplification is simply to stop the iteration when the restored image appears to become too noisy. However, in most cases the number of iterations needed is different for different parts of the image. Hundreds of iterations may be required to get a good fit to the high signal-to-noise image of a bright star, while a smooth, extended object may be fitted well after only a few iterations. Thus, one would like to be able to slow or stop the iteration automatically in regions where a smooth model fits the data adequately, while continuing to iterate in regions where there are sharp features (edges or point sources). The need for a spatially adaptive convergence criterion is exacerbated when CCD readout noise is included in the RL algorithm (Snyder, Hammoud, & White, 1993, JOSA A , 10 , 1014), because the rate of convergence is then slower for faint stars than for bright stars. This paper will

  1. Multi-Scale Patch-Based Image Restoration.

    Science.gov (United States)

    Papyan, Vardan; Elad, Michael

    2016-01-01

    Many image restoration algorithms in recent years are based on patch processing. The core idea is to decompose the target image into fully overlapping patches, restore each of them separately, and then merge the results by a plain averaging. This concept has been demonstrated to be highly effective, leading often times to the state-of-the-art results in denoising, inpainting, deblurring, segmentation, and other applications. While the above is indeed effective, this approach has one major flaw: the prior is imposed on intermediate (patch) results, rather than on the final outcome, and this is typically manifested by visual artifacts. The expected patch log likelihood (EPLL) method by Zoran and Weiss was conceived for addressing this very problem. Their algorithm imposes the prior on the patches of the final image, which in turn leads to an iterative restoration of diminishing effect. In this paper, we propose to further extend and improve the EPLL by considering a multi-scale prior. Our algorithm imposes the very same prior on different scale patches extracted from the target image. While all the treated patches are of the same size, their footprint in the destination image varies due to subsampling. Our scheme comes to alleviate another shortcoming existing in patch-based restoration algorithms--the fact that a local (patch-based) prior is serving as a model for a global stochastic phenomenon. We motivate the use of the multi-scale EPLL by restricting ourselves to the simple Gaussian case, comparing the aforementioned algorithms and showing a clear advantage to the proposed method. We then demonstrate our algorithm in the context of image denoising, deblurring, and super-resolution, showing an improvement in performance both visually and quantitatively.

  2. Restoration of a single superresolution image from several blurred, noisy, and undersampled measured images.

    Science.gov (United States)

    Elad, M; Feuer, A

    1997-01-01

    The three main tools in the single image restoration theory are the maximum likelihood (ML) estimator, the maximum a posteriori probability (MAP) estimator, and the set theoretic approach using projection onto convex sets (POCS). This paper utilizes the above known tools to propose a unified methodology toward the more complicated problem of superresolution restoration. In the superresolution restoration problem, an improved resolution image is restored from several geometrically warped, blurred, noisy and downsampled measured images. The superresolution restoration problem is modeled and analyzed from the ML, the MAP, and POCS points of view, yielding a generalization of the known superresolution restoration methods. The proposed restoration approach is general but assumes explicit knowledge of the linear space- and time-variant blur, the (additive Gaussian) noise, the different measured resolutions, and the (smooth) motion characteristics. A hybrid method combining the simplicity of the ML and the incorporation of nonellipsoid constraints is presented, giving improved restoration performance, compared with the ML and the POCS approaches. The hybrid method is shown to converge to the unique optimal solution of a new definition of the optimization problem. Superresolution restoration from motionless measurements is also discussed. Simulations demonstrate the power of the proposed methodology.

  3. Image Restoration Phase-Filtering Lateral Superresolution Confocal Microscopy

    Institute of Scientific and Technical Information of China (English)

    ZHAO Wei-Qian; QIU Li-Rong; CHEN Shan-Shan; FENG Zheng-De

    2006-01-01

    @@ Image restoration phase-filtering lateral superresolution confocal microscopy, a new approach, is proposed to achieve lateral superresolution using a confocal microscope. This approach uses a lateral superresolution pupil filter to preliminarily improve its lateral resolution and uses a single-image superresolution restoration technique based on a maximum likelihood estimate to further improve its lateral resolution. The new approach has the advantages of a low cost and the remarkable superresolution effect without excessive system complexity. Experiments indicate that the proposed approach can improve the lateral resolution of a confocal microscope from 0.3μm to less than 0.1 μm when λ = 632.8 nm and NA =0.85.

  4. A new trust region algorithm for image restoration

    Institute of Scientific and Technical Information of China (English)

    WEN Zaiwen; WANG Yanfei

    2005-01-01

    The image restoration problems play an important role in remote sensing and astronomical image analysis. One common method for the recovery of a true image from corrupted or blurred image is the least squares error (LSE) method. But the LSE method is unstable in practical applications. A popular way to overcome instability is the Tikhonov regularization. However, difficulties will encounter when adjusting the so-called regularization parameter α. Moreover, how to truncate the iteration at appropriate steps is also challenging. In this paper we use the trust region method to deal with the image restoration problem, meanwhile, the trust region subproblem is solved by the truncated Lanczos method and the preconditioned truncated Lanczos method. We also develop a fast algorithm for evaluating the Kronecker matrix-vector product when the matrix is banded. The trust region method is very stable and robust, and it has the nice property of updating the trust region automatically. This releases us from tedious finding the regularization parameters and truncation levels. Some numerical tests on remotely sensed images are given to show that the trust region method is promising.

  5. Peplography: an image restoration technique through scattering media

    Science.gov (United States)

    Cho, Myungjin; Cho, Ki-Ok; Kim, Youngjun

    2016-06-01

    In this paper, we propose an image restoration technique through scattering media. Under natural light an imaging through scattering media is a big challenge in many applications. To overcome this challenge, many methods have been reported such as non-invasive imaging, ghost imaging, and wavefront shaping. However, their results have not been sufficient for observers. In this paper, we estimate the scattering media by statistical estimation such as maximum likelihood estimation. By removing this estimated scattering media from the original image, we can obtain the image with only ballistic photons. Then, the ballistic photons can be detected by photon counting imaging concept. In addition, since each basic color channel has its own wavelength, color photon counting process can be implemented. To enhance the visual quality of the result image, a passive three-dimensional (3D) imaging technique such as integral imaging is used. To prove our method and show the better performance, we carried out optical experiments and calculate mean square error (MSE).

  6. Group-based sparse representation for image restoration.

    Science.gov (United States)

    Zhang, Jian; Zhao, Debin; Gao, Wen

    2014-08-01

    Traditional patch-based sparse representation modeling of natural images usually suffer from two problems. First, it has to solve a large-scale optimization problem with high computational complexity in dictionary learning. Second, each patch is considered independently in dictionary learning and sparse coding, which ignores the relationship among patches, resulting in inaccurate sparse coding coefficients. In this paper, instead of using patch as the basic unit of sparse representation, we exploit the concept of group as the basic unit of sparse representation, which is composed of nonlocal patches with similar structures, and establish a novel sparse representation modeling of natural images, called group-based sparse representation (GSR). The proposed GSR is able to sparsely represent natural images in the domain of group, which enforces the intrinsic local sparsity and nonlocal self-similarity of images simultaneously in a unified framework. In addition, an effective self-adaptive dictionary learning method for each group with low complexity is designed, rather than dictionary learning from natural images. To make GSR tractable and robust, a split Bregman-based technique is developed to solve the proposed GSR-driven ℓ0 minimization problem for image restoration efficiently. Extensive experiments on image inpainting, image deblurring and image compressive sensing recovery manifest that the proposed GSR modeling outperforms many current state-of-the-art schemes in both peak signal-to-noise ratio and visual perception.

  7. Efficient cultural heritage image restoration with nonuniform illumination enhancement

    Science.gov (United States)

    Jmal, Marwa; Souidene, Wided; Attia, Rabah

    2017-01-01

    Cultural heritage digitization has been of research interest for several decades. For such, the quality of the stored images should be pleasant to see. However, as images captured by digital devices may include undesirable effects, conducting an enhancement on the image is essential. In this context, we present a framework for the purpose of cultural heritage image illumination enhancement. First, a mapping curve based on saturation feedback is created to adjust the contrast. Then illumination is enhanced by applying a modified homomorphic filter in the frequency domain. The technique employs an optimization search process based on the efficient golden section search algorithm to compute the optimal parameters to produce the enhanced image. Finally, a color restoration function is applied to overcome the problem of color violation. The resulted image represents a trade-off among local contrast improvement, detail enhancement, and preserving the naturalness of the image. Experiments are conducted on a collected dataset of cultural heritage images and compared to some of the state-of-the-art image enhancement methods using a set of quantitative assessments criteria. Results have shown that our proposed approach is able to accomplish a wide set of the performance goals.

  8. Image Restoration Using Functional and Anatomical Information Fusion with Application to SPECT-MRI Images

    Directory of Open Access Journals (Sweden)

    S. Benameur

    2009-01-01

    Full Text Available Image restoration is usually viewed as an ill-posed problem in image processing, since there is no unique solution associated with it. The quality of restored image closely depends on the constraints imposed of the characteristics of the solution. In this paper, we propose an original extension of the NAS-RIF restoration technique by using information fusion as prior information with application in SPECT medical imaging. That extension allows the restoration process to be constrained by efficiently incorporating, within the NAS-RIF method, a regularization term which stabilizes the inverse solution. Our restoration method is constrained by anatomical information extracted from a high resolution anatomical procedure such as magnetic resonance imaging (MRI. This structural anatomy-based regularization term uses the result of an unsupervised Markovian segmentation obtained after a preliminary registration step between the MRI and SPECT data volumes from each patient. This method was successfully tested on 30 pairs of brain MRI and SPECT acquisitions from different subjects and on Hoffman and Jaszczak SPECT phantoms. The experiments demonstrated that the method performs better, in terms of signal-to-noise ratio, than a classical supervised restoration approach using a Metz filter.

  9. Image restoration for indirectly far-field image using microlenses array integrated with LCD

    Science.gov (United States)

    Yang, Fugui; Wang, Anting; Lei, Dong; Zhe, Cui; Ming, Hai

    2010-10-01

    Image restoration for constructing high-spatial-resolution images in an imaging system which realizes indirectly far-filed imaging by integrating the microlenses array with LCD is reported. We have investigated the indirectly far-field imaging condition where adjacent sampling points contribute the detected signal. Experimental setup with microlens of 500 μm diameter and 8 mm focal length is built to prove this condition by studying performance of image restoration using modified point spread function (PSF). Since any one iterative method is not optimal for all image deblurring problems, some deblurring algorithms including direct deconvolution and iterative deconvolution are applied to our imaging system and we compared the effectiveness of these iterative procedures to choose right one for our use.

  10. Spatially Adaptive Image Restoration Using Fuzzy Punctual Kriging

    Institute of Scientific and Technical Information of China (English)

    Anwar M. Mirza; Asmatullah Chaudhry; Badre Munir

    2007-01-01

    We present a general formulation based on punctual kriging and fuzzy concepts for image restoration in spatial domain. Gray-level images degraded with Gaussian white noise have been considered. Based on the pixel local neighborhood, fuzzy logic has been employed intelligently to avoid unnecessary estimation of a pixel. The intensity estimation of the selected pixels is then carried out by employing punctual kriging in conjunction with the method of Lagrange multipliers and estimates of local semi-variances. Application of such a hybrid technique performing both selection and intensity estimation of a pixel demonstrates substantial improvement in the image quality as compared to the adaptive Wiener filter and existing fuzzy- kriging approaches. It has been found that these filters achieve noise reduction without loss of structural detail information, as indicated by their higher structure similarity indices, peak signal to noise ratios and the new variogram based quality measures.

  11. Image mathematical morphology and image restoration application in detecting underground bin level

    Institute of Scientific and Technical Information of China (English)

    SUN Ji-ping; WU Bing

    2004-01-01

    By using image recognition technology, the underground bin level can be detdcted. The bin image is noised by vibration, atomy, backgroun and so on. The image restoration and image mathematical morphology were used based on neural network.A modified Hopfield network was presented for image restoration. The greed algorithm with n-simultaneous updates and apartially asynchronous algorithm were combined, improving convergence and avoiding synchronization penalties. Mathematical morphology was widely applicated in digital image processing. The basic idea of mathematical morphology is to use construction element measure image morphology for solving understand problem. Presented advanced Cellular neural network that forms MMCNN equation to be suit for mathematical morphology filter. It gave the theory of MMCNN dynamic extent and stable state. It was evidenced that arrived mathematical morphology filter through steady of dynamic precess in definite condition. The results of implementation were applied in detecting undergroug bin level.

  12. Image Restoration and Denoising By Using Nonlocally Centralized Sparse Representation and Histogram Clipping

    Directory of Open Access Journals (Sweden)

    Dr. T. V. S. Prasad Gupta

    2014-10-01

    Full Text Available Due to the degradation of observed image the noisy, blurred, Distorted image can be occurred .for restoring image information we propose the sparse representations by conventional modelsmay not be accurate enough for a faithful reconstruction of the original image. To improve the performance of sparse representation-based image restoration,In this method the sparse coding noise is added for image restoration, due to this image restoration the sparse coefficients of original image can be detected. The so-called nonlocally centralized sparse representation (NCSR model is as simple as the standard sparse representation model,for denoising the image here we use the Histogram clipping method by using histogram based sparse representation effectively reduce the noise.and also implement the TMR filter for Quality image.various types of image restoration problems, including denoising, deblurring and super-resolution, validate the generality and state-of-the-art performance of the proposed algorithm.

  13. Test images for the maximum entropy image restoration method

    Science.gov (United States)

    Mackey, James E.

    1990-01-01

    One of the major activities of any experimentalist is data analysis and reduction. In solar physics, remote observations are made of the sun in a variety of wavelengths and circumstances. In no case is the data collected free from the influence of the design and operation of the data gathering instrument as well as the ever present problem of noise. The presence of significant noise invalidates the simple inversion procedure regardless of the range of known correlation functions. The Maximum Entropy Method (MEM) attempts to perform this inversion by making minimal assumptions about the data. To provide a means of testing the MEM and characterizing its sensitivity to noise, choice of point spread function, type of data, etc., one would like to have test images of known characteristics that can represent the type of data being analyzed. A means of reconstructing these images is presented.

  14. A Stochastic Approach for Blurred Image Restoration and Optical Flow Computation on Field Image Sequence

    Institute of Scientific and Technical Information of China (English)

    高文; 陈熙霖

    1997-01-01

    The blur in target images caused by camera vibration due to robot motion or hand shaking and by object(s) moving in the background scene is different to deal with in the computer vision system.In this paper,the authors study the relation model between motion and blur in the case of object motion existing in video image sequence,and work on a practical computation algorithm for both motion analysis and blut image restoration.Combining the general optical flow and stochastic process,the paper presents and approach by which the motion velocity can be calculated from blurred images.On the other hand,the blurred image can also be restored using the obtained motion information.For solving a problem with small motion limitation on the general optical flow computation,a multiresolution optical flow algoritm based on MAP estimation is proposed. For restoring the blurred image ,an iteration algorithm and the obtained motion velocity are used.The experiment shows that the proposed approach for both motion velocity computation and blurred image restoration works well.

  15. Fast approach to infrared image restoration based on shrinkage functions calibration

    Science.gov (United States)

    Zhang, Chengshuo; Shi, Zelin; Xu, Baoshu; Feng, Bin

    2016-05-01

    High-quality image restoration in real time is a challenge for infrared imaging systems. We present a fast approach to infrared image restoration based on shrinkage functions calibration. Rather than directly modeling the prior of sharp images to obtain the shrinkage functions, we calibrate them for restoration directly by using the acquirable sharp and blurred image pairs from the same infrared imaging system. The calibration method is employed to minimize the sum of squared errors between sharp images and restored images from the blurred images. Our restoration algorithm is noniterative and its shrinkage functions are stored in the look-up tables, so an architecture solution of pipeline structure can work in real time. We demonstrate the effectiveness of our approach by testing its quantitative performance from simulation experiments and its qualitative performance from a developed wavefront coding infrared imaging system.

  16. Image Restoration Based onMulti-channel Blind Restoration and Sparse Representation Method%基于多通道盲复原和改进K-SVD模型的图像恢复

    Institute of Scientific and Technical Information of China (English)

    陈杰; 尚丽; 孙站里

    2015-01-01

    图像盲复原( IBR)问题一直是图像处理中的重要研究课题。目前空间不变的多通道图像盲复原算法研究较为普遍,这种算法具有较好的盲去模糊效果,但是对噪声的抑制能力不足,特别是对含有大量噪声的低分辨率图像而言,消噪效果较差。基于K-奇异值分解( K-SVD )的模型能够有效地处理噪声方差较大的图像,但是不能自适应图像的稀疏先验性。为了解决上述问题,在全变分( TV)多通道IBR算法处理的基础上,结合一种改进的K-SVD消噪模型的优势,提出了一种新的组合图像恢复方法。改进的K-SVD模型考虑了图像特征系数的稀疏先验知识和最大化稀疏度,具有自适应的消噪鲁棒性。分别采用模拟的和真实的低分辨率图像(毫米波图像)进行测试,与采用单一的多通道盲恢复和图像消噪算法相比,实验结果表明所提出的图像恢复方法具有较好的视觉效果和较高的信噪比。%The problem of image blind restoration ( IBR) has been the important research issue in image process-ing. At present, the research of multi-channel with space invariant is very common. This algorithm behaves certain advantages in blind de-blurring, but it is limited to denoise images. Especially, to low resolution ( LR ) images, which contain much unknown noise, the restored effect is worse only using the multi-channel restoration technique. K-mean based singular value decomposition ( K-SVD) model can denoise images with large noise variance, however, it is not self-adaptive to an image’ s priors. To solve this defect, on the basis of processed results by the total variation ( TV) based multi-channel restoration algorithm, further combined a modified K-SVD model’ s advantage in denoising images, a novel combined image restoration method is discussed here. This modified K-SVD model considers the sparse priors and maximize sparsity of image feature coefficients and

  17. Image restoration based on the discrete fraction Fourier transform

    Science.gov (United States)

    Yan, Peimin; Mo, Yu L.; Liu, Hong

    2001-09-01

    The fractional Fourier transform is the powerful tool for time-variant signal analysis. For space-variant degradation and non-stationary processes the filtering in fractional Fourier domains permits reduction of the error compared with ordinary Fourier domain filtering. In this paper the concept of filtering in fractional Fourier domains is applied to the problem of estimating degraded images. Efficient digital implementation using discrete Hermite eigenvectors can provide similar results to match the continuous outputs. Expressions for the 2D optimal filter function in fractional domains will be given for transform domains characterized by the two rotation angle parameters of the 2D fractional Fourier transform. The proposed method is used to restore images that have several degradations in the experiments. The results show that the method presented in this paper is valid.

  18. Accelerated edge-preserving image restoration without boundary artifacts.

    Science.gov (United States)

    Matakos, Antonios; Ramani, Sathish; Fessler, Jeffrey A

    2013-05-01

    To reduce blur in noisy images, regularized image restoration methods have been proposed that use nonquadratic regularizers (like l1 regularization or total-variation) that suppress noise while preserving edges in the image. Most of these methods assume a circulant blur (periodic convolution with a blurring kernel) that can lead to wraparound artifacts along the boundaries of the image due to the implied periodicity of the circulant model. Using a noncirculant model could prevent these artifacts at the cost of increased computational complexity. In this paper, we propose to use a circulant blur model combined with a masking operator that prevents wraparound artifacts. The resulting model is noncirculant, so we propose an efficient algorithm using variable splitting and augmented Lagrangian (AL) strategies. Our variable splitting scheme, when combined with the AL framework and alternating minimization, leads to simple linear systems that can be solved noniteratively using fast Fourier transforms (FFTs), eliminating the need for more expensive conjugate gradient-type solvers. The proposed method can also efficiently tackle a variety of convex regularizers, including edge-preserving (e.g., total-variation) and sparsity promoting (e.g., l1-norm) regularizers. Simulation results show fast convergence of the proposed method, along with improved image quality at the boundaries where the circulant model is inaccurate.

  19. Accelerated Edge-Preserving Image Restoration Without Boundary Artifacts

    Science.gov (United States)

    Matakos, Antonios; Ramani, Sathish; Fessler, Jeffrey A.

    2013-01-01

    To reduce blur in noisy images, regularized image restoration methods have been proposed that use non-quadratic regularizers (like l1 regularization or total-variation) that suppress noise while preserving edges in the image. Most of these methods assume a circulant blur (periodic convolution with a blurring kernel) that can lead to wraparound artifacts along the boundaries of the image due to the implied periodicity of the circulant model. Using a non-circulant model could prevent these artifacts at the cost of increased computational complexity. In this work we propose to use a circulant blur model combined with a masking operator that prevents wraparound artifacts. The resulting model is non-circulant, so we propose an efficient algorithm using variable splitting and augmented Lagrangian (AL) strategies. Our variable splitting scheme, when combined with the AL framework and alternating minimization, leads to simple linear systems that can be solved non-iteratively using FFTs, eliminating the need for more expensive CG-type solvers. The proposed method can also efficiently tackle a variety of convex regularizers including edge-preserving (e.g., total-variation) and sparsity promoting (e.g., l1 norm) regularizers. Simulation results show fast convergence of the proposed method, along with improved image quality at the boundaries where the circulant model is inaccurate. PMID:23372080

  20. Fruit fly optimization based least square support vector regression for blind image restoration

    Science.gov (United States)

    Zhang, Jiao; Wang, Rui; Li, Junshan; Yang, Yawei

    2014-11-01

    The goal of image restoration is to reconstruct the original scene from a degraded observation. It is a critical and challenging task in image processing. Classical restorations require explicit knowledge of the point spread function and a description of the noise as priors. However, it is not practical for many real image processing. The recovery processing needs to be a blind image restoration scenario. Since blind deconvolution is an ill-posed problem, many blind restoration methods need to make additional assumptions to construct restrictions. Due to the differences of PSF and noise energy, blurring images can be quite different. It is difficult to achieve a good balance between proper assumption and high restoration quality in blind deconvolution. Recently, machine learning techniques have been applied to blind image restoration. The least square support vector regression (LSSVR) has been proven to offer strong potential in estimating and forecasting issues. Therefore, this paper proposes a LSSVR-based image restoration method. However, selecting the optimal parameters for support vector machine is essential to the training result. As a novel meta-heuristic algorithm, the fruit fly optimization algorithm (FOA) can be used to handle optimization problems, and has the advantages of fast convergence to the global optimal solution. In the proposed method, the training samples are created from a neighborhood in the degraded image to the central pixel in the original image. The mapping between the degraded image and the original image is learned by training LSSVR. The two parameters of LSSVR are optimized though FOA. The fitness function of FOA is calculated by the restoration error function. With the acquired mapping, the degraded image can be recovered. Experimental results show the proposed method can obtain satisfactory restoration effect. Compared with BP neural network regression, SVR method and Lucy-Richardson algorithm, it speeds up the restoration rate and

  1. Satellite image blind restoration based on surface fitting and multivariate model

    Institute of Scientific and Technical Information of China (English)

    CHEN Xin-bing; YANG Shi-zhi; WANG Xian-hua; QIAO Yan-li

    2009-01-01

    Owing to the blurring effect from atmosphere and camera system in the satellite imaging a blind image restoration algo-rithm is proposed which includes the modulation transfer function (MTF) estimation and the image restoration. In the MTF estimation stage, based on every degradation process of satellite imaging-chain, a combined parametric model of MTF is given and used to fit the surface of normalized logarithmic amplitude spectrum of degraded image. In the image restoration stage, a maximum a posteriori (MAP) based edge-preserving image restoration method is presented which introduces multivariate Laplacian model to characterize the prior distribution of wavelet coefficients of original image. During the image restoration, in order to avoid solving high nonlinear equations, optimization transfer algorithm is adopted to decom-pose the image restoration procedure into two simple steps: Landweber iteration and wavelet thresholding denoising. In the numerical experiment, the satellite image restoration results from SPOT-5 and high resolution camera (HR) of China & Brazil earth resource satellite (CBERS-02B) ane compared, and the proposed algorithm is superior in the image edge preservation and noise inhibition.

  2. Dictionary construction in sparse methods for image restoration

    Energy Technology Data Exchange (ETDEWEB)

    Wohlberg, Brendt [Los Alamos National Laboratory

    2010-01-01

    Sparsity-based methods have achieved very good performance in a wide variety of image restoration problems, including denoising, inpainting, super-resolution, and source separation. These methods are based on the assumption that the image to be reconstructed may be represented as a superposition of a few known components, and the appropriate linear combination of components is estimated by solving an optimization such as Basis Pursuit De-Noising (BPDN). Considering that the K-SVD constructs a dictionary which has been optimised for mean performance over a training set, it is not too surprising that better performance can be achieved by selecting a custom dictionary for each individual block to be reconstructed. The nearest neighbor dictionary construction can be understood geometrically as a method for estimating the local projection into the manifold of image blocks, whereas the K-SVD dictionary makes more sense within a source-coding framework (it is presented as a generalization of the k-means algorithm for constructing a VQ codebook), is therefore, it could be argued, less appropriate in principle, for reconstruction problems. One can, of course, motivate the use of the K-SVD in reconstruction application on practical grounds, avoiding the computational expense of constructing a different dictionary for each block to be denoised. Since the performance of the nearest neighbor dictionary decreases when the dictionary becomes sufficiently large, this method is also superior to the approach of utilizing the entire training set as a dictionary (and this can also be understood within the image block manifold model). In practical terms, the tradeoff is between the computational cost of a nearest neighbor search (which can be achieved very efficiently), or of increased cost at the sparse optimization.

  3. Image restoration by the method of convex projections: part 2 applications and numerical results.

    Science.gov (United States)

    Sezan, M I; Stark, H

    1982-01-01

    The image restoration theory discussed in a previous paper by Youla and Webb [1] is applied to a simulated image and the results compared with the well-known method known as the Gerchberg-Papoulis algorithm. The results show that the method of image restoration by projection onto convex sets, by providing a convenient technique for utilizing a priori information, performs significantly better than the Gerchberg-Papoulis method.

  4. Ultrasonic image restoration based on support vector machine for surfacing interface testing

    Institute of Scientific and Technical Information of China (English)

    Gao Shuangsheng; Gang Tie; Chi Dazhao

    2007-01-01

    In order to restore the degraded ultrasonic C-scan image for testing surfacing interface, a method based on support vector regression (SVR) network is proposed. By using the image of a simulating defect, the network is trained and a mapping relationship between the degraded and restored image is founded. The degraded C-scan image of Cu-Steel surfacing interface is processed by the trained network and improved image is obtained. The result shows that the method can effectively suppress the noise and deblur the defect edge in the image, and provide technique support for quality and reliability evaluation of the surfacing weld.

  5. Bayesian Image Restoration Using a Large-Scale Total Patch Variation Prior

    Directory of Open Access Journals (Sweden)

    Yang Chen

    2011-01-01

    Full Text Available Edge-preserving Bayesian restorations using nonquadratic priors are often inefficient in restoring continuous variations and tend to produce block artifacts around edges in ill-posed inverse image restorations. To overcome this, we have proposed a spatial adaptive (SA prior with improved performance. However, this SA prior restoration suffers from high computational cost and the unguaranteed convergence problem. Concerning these issues, this paper proposes a Large-scale Total Patch Variation (LS-TPV Prior model for Bayesian image restoration. In this model, the prior for each pixel is defined as a singleton conditional probability, which is in a mixture prior form of one patch similarity prior and one weight entropy prior. A joint MAP estimation is thus built to ensure the iteration monotonicity. The intensive calculation of patch distances is greatly alleviated by the parallelization of Compute Unified Device Architecture(CUDA. Experiments with both simulated and real data validate the good performance of the proposed restoration.

  6. Comparison-based Image Quality Assessment for Selecting Image Restoration Parameters.

    Science.gov (United States)

    Liang, Haoyi; Weller, Daniel

    2016-08-19

    Image quality assessment (IQA) is traditionally classified into full-reference (FR) IQA, reduced-reference (RR) IQA, and no-reference (NR) IQA according to the amount of information required from the original image. Although NRIQA and RR-IQA are widely used in practical applications, room for improvement still remains because of the lack of the reference image. Inspired by the fact that in many applications, such as parameter selection for image restoration algorithms, a series of distorted images are available, the authors propose a novel comparison-based image quality assessment (C-IQA) framework. The new comparison-based framework parallels FRIQA by requiring two input images, and resembles NR-IQA by not using the original image. As a result, the new comparisonbased approach has more application scenarios than FR-IQA does, and takes greater advantage of the accessible information than the traditional single-input NR-IQA does. Further, C-IQA is compared with other state-of-the-art NR-IQA methods and another RR-IQA method on two widely used IQA databases. Experimental results show that C-IQA outperforms the other methods for parameter selection, and the parameter trimming framework combined with C-IQA saves the computation of iterative image reconstruction up to 80%.

  7. Research on a novel restoration algorithm of turbulence-degraded images with alternant iterations

    Institute of Scientific and Technical Information of China (English)

    Liu Chunsheng; Hong Hanyu; Zhang Tianxu

    2006-01-01

    A new restoration algorithm based on double loops and alternant iterations is proposed to restore the object image effectively from a few frames of turbulence-degraded images. Based on the double loops, the iterative relations for estimating the turbulent point spread function PSF and object image alternately are derived. The restoration experiments have been made on computers, showing that the proposed algorithm can obtain the optimal estimations of the object and the point spread function, with the feasibility and practicality of the proposed algorithm being convincing.

  8. Image restoration using 2D autoregressive texture model and structure curve construction

    Science.gov (United States)

    Voronin, V. V.; Marchuk, V. I.; Petrosov, S. P.; Svirin, I.; Agaian, S.; Egiazarian, K.

    2015-05-01

    In this paper an image inpainting approach based on the construction of a composite curve for the restoration of the edges of objects in an image using the concepts of parametric and geometric continuity is presented. It is shown that this approach allows to restore the curved edges and provide more flexibility for curve design in damaged image by interpolating the boundaries of objects by cubic splines. After edge restoration stage, a texture restoration using 2D autoregressive texture model is carried out. The image intensity is locally modeled by a first spatial autoregressive model with support in a strongly causal prediction region on the plane. Model parameters are estimated by Yule-Walker method. Several examples considered in this paper show the effectiveness of the proposed approach for large objects removal as well as recovery of small regions on several test images.

  9. Multi-scale retinex with color restoration image enhancement based on Gaussian filtering and guided filtering

    Science.gov (United States)

    Ma, Jinxiang; Fan, Xinnan; Ni, Jianjun; Zhu, Xifang; Xiong, Chao

    2017-07-01

    In order to restore image color and enhance contrast of remote sensing image without suffering from color cast and insufficient detail enhancement, a novel improved multi-scale retinex with color restoration (MSRCR) image enhancement algorithm based on Gaussian filtering and guided filtering was proposed in this paper. Firstly, multi-scale Gaussian filtering functions were used to deal with the original image to obtain the rough illumination components. Secondly, accurate illumination components were acquired by using the guided filtering functions. Then, combining with four-direction Sobel edge detector, a self-adaptive weight selection nonlinear image enhancement was carried out. Finally, a series of evaluate metrics such as mean, MSE, PSNR, contrast and information entropy were used to assess the enhancement algorithm. The results showed that the proposed algorithm can suppress effectively noise interference, enhance the image quality and restore image color effectively.

  10. Restoration of Scanning Tunneling Microscope Images by means of Two-Dimensional Maximum Entropy Method

    Science.gov (United States)

    Matsumoto, Hisanori; Tokiwano, Kazuo; Hosoi, Hirotaka; Sueoka, Kazuhisa; Mukasa, Koichi

    2002-05-01

    We present a new technique for the restoration of scanning tunneling microscopy (STM) images, which is a two-dimensional extension of a recently developed statistical approach based on the one-dimensional least-squares method (LSM). An STM image is regarded as a realization of a stochastic process and assumed to be a composition of an underlying image and noise. We express the underlying image in terms of a two-dimensional generalized trigonometric polynomial suitable for representing the atomic protrusions in STM images. The optimization of the polynomial is performed by the two-dimensional LSM combined with the power spectral density function estimated by means of the maximum entropy method (MEM) iterative algorithm for two-dimensional signals. The restored images are obtained as the optimum least-squares fitting polynomial which is a continuous surface. We apply this technique to modeled and actual STM data. Results show that the present method yields a reasonable restoration of STM images.

  11. Novel recovery mechanism for the restoration of image contents in teleconsultation sessions.

    Science.gov (United States)

    Wang, Cheng-Hsiung; Ssu, Kuo-Feng; Chung, Pau-Choo; Jiau, Hewijin Christine; Shih, Wei-Te

    2012-01-01

    In teleconsultation sessions, a critical dependency exists between the image contents and the type and sequential order of the image processing commands used by the various participants. Accordingly, for re-entrant/late users, a significant challenge exists in restoring the image contents of the teleconsultation session in such a way that all the participants maintain a consistent view of the medical images. In this paper, this problem is resolved using a novel recovery mechanism comprising two major components, namely an enhanced content-recording scheme designated as three-level indexing hierarchy (TIH) and a prioritized recovery policy. TIH maintains a record of all the commands which affect the appearance of each of medical images such that when a restoration process is required, these image-affect commands can be rapidly identified and transmitted to the user. As a result, a significant reduction can be gained in both the command identification/transmission time and the image restoration time compared to traditional recovery schemes, which restore the contents by re-executing all of the commands invoked during the course of the session. The prioritized recovery policy further reduces the time required for re-entrant/late users to catch up with the on-going session by utilizing the cross-linkage design within the TIH architecture to restore the foreground image (i.e. the image under current discussion) before the background images are restored (i.e. the remaining images in the session). To resolve the problem which arises when a background image is selected as the new foreground image before the restoration process is completed, the prioritized recovery policy maintains a set of resuming pointers for each re-entrant/late user to facilitate the process of suspending the current restoration process and switching to the restoration of the new foreground image. The evaluation results confirm that the TIH architecture and prioritized recovery policy yield a

  12. Radial Basis Function Neural Network Based Super-Resolution Restoration for an Underspled Image

    Institute of Scientific and Technical Information of China (English)

    苏秉华; 金伟其; 牛丽红

    2004-01-01

    To achieve restoration of high frequency information for an underspled and degraded low-resolution image, a nonlinear and real-time processing method-the radial basis function (RBF) neural network based super-resolution method of restoration is proposed. The RBF network configuration and processing method is suitable for a high resolution restoration from an underspled low-resolution image. The soft-competition learning scheme based on the k-means algorithm is used, and can achieve higher mapping approximation accuracy without increase in the network size. Experiments showed that the proposed algorithm can achieve a super-resolution restored image from an underspled and degraded low-resolution image, and requires a shorter training time when compared with the multiplayer perception (MLP) network.

  13. High resolution retinal image restoration with wavefront sensing and self-extracted filtering

    Science.gov (United States)

    Yang, Shuyu; Erry, Gavin; Nemeth, Sheila; Mitra, Sunanda; Soliz, Peter

    2005-04-01

    Diagnosis and treatment of retinal diseases such as diabetic retinopathy commonly rely on a clear view of the retina. The challenge in obtaining high quality retinal image lies in the design of the imaging system that can reduce the strong aberrations of the human eye. Since the amplitudes of human eye aberrations decrease rapidly as the aberration order goes up, it is more cost-effective to correct low order aberrations with adaptive optical devices while process high order aberrations through image processing. A cost effective fundus imaging device that can capture high quality retinal images with 2-5 times higher resolution than conventional retinal images has been designed [1]. This imager improves image quality by attaching complementary adaptive optical components to a conventional fundus camera. However, images obtained with the high resolution camera are still blurred due to some uncorrected aberrations as well as defocusing resulting from non-isoplanatic effect. Therefore, advanced image restoration algorithms have been employed for further improvement in image quality. In this paper, we use wavefront-based and self-extracted blind deconvolution techniques to restore images captured by the high resolution fundus camera. We demonstrate that through such techniques, pathologies that are critical to retinal disease diagnosis but not clear or not observable in the original image can be observed clearly in the restored images. Image quality evaluation is also used to finalize the development of a cost-effective, fast, and automated diagnostic system that can be used clinically.

  14. Stokes imaging polarimetry using image restoration at the Swedish 1-m Solar Telescope

    CERN Document Server

    van Noort, M J

    2008-01-01

    Aims: We aim to achieve high spatial resolution as well as high polarimetric sensitivity, using an earth-based 1m-class solar telescope, for the study of magnetic fine structure on the Sun. Methods: We use a setup with 3 high-speed, low-noise cameras to construct datasets with interleaved polarimetric states, particularly suitable for Multi-Object Multi-Frame Blind Deconvolution image restorations. We discuss the polarimetric calibration routine as well as various potential sources of error in the results. Results: We obtained near diffraction limited images, with a noise level of approximately 10^(-3) I(cont). We confirm that dark-cores have a weaker magnetic field and at a lower inclination angle with respect to the solar surface than the edges of the penumbral filament. We show that the magnetic field strength in faculae-striations is significantly lower than in other nearby parts of the faculae.

  15. CT image sequence restoration based on sparse and low-rank decomposition.

    Directory of Open Access Journals (Sweden)

    Shuiping Gou

    Full Text Available Blurry organ boundaries and soft tissue structures present a major challenge in biomedical image restoration. In this paper, we propose a low-rank decomposition-based method for computed tomography (CT image sequence restoration, where the CT image sequence is decomposed into a sparse component and a low-rank component. A new point spread function of Weiner filter is employed to efficiently remove blur in the sparse component; a wiener filtering with the Gaussian PSF is used to recover the average image of the low-rank component. And then we get the recovered CT image sequence by combining the recovery low-rank image with all recovery sparse image sequence. Our method achieves restoration results with higher contrast, sharper organ boundaries and richer soft tissue structure information, compared with existing CT image restoration methods. The robustness of our method was assessed with numerical experiments using three different low-rank models: Robust Principle Component Analysis (RPCA, Linearized Alternating Direction Method with Adaptive Penalty (LADMAP and Go Decomposition (GoDec. Experimental results demonstrated that the RPCA model was the most suitable for the small noise CT images whereas the GoDec model was the best for the large noisy CT images.

  16. Box-constrained Total-variation Image Restoration with Automatic Parameter Estimation

    Institute of Scientific and Technical Information of China (English)

    HE Chuan; HU Chang-Hua; ZHANG Wei; SHI Biao

    2014-01-01

    The box constraints in image restoration have been arousing great attention, since the pixels of a digital image can attain only a finite number of values in a given dynamic range. This paper studies the box-constrained total-variation (TV) image restoration problem with automatic regularization parameter estimation. By adopting the variable splitting technique and introducing some auxiliary variables, the box-constrained TV minimization problem is decomposed into a sequence of subproblems which are easier to solve. Then the alternating direction method (ADM) is adopted to solve the related subproblems. By means of Morozov0s discrepancy principle, the regularization parameter can be updated adaptively in a closed form in each iteration. Image restoration experiments indicate that with our strategies, more accurate solutions are achieved, especially for image with high percentage of pixel values lying on the boundary of the given dynamic range.

  17. Supervised restoration of degraded medical images using multiple-point geostatistics.

    Science.gov (United States)

    Pham, Tuan D

    2012-06-01

    Reducing noise in medical images has been an important issue of research and development for medical diagnosis, patient treatment, and validation of biomedical hypotheses. Noise inherently exists in medical and biological images due to the acquisition and transmission in any imaging devices. Being different from image enhancement, the purpose of image restoration is the process of removing noise from a degraded image in order to recover as much as possible its original version. This paper presents a statistically supervised approach for medical image restoration using the concept of multiple-point geostatistics. Experimental results have shown the effectiveness of the proposed technique which has potential as a new methodology for medical and biological image processing.

  18. Point spread function modeling and images restoration for cone-beam CT

    CERN Document Server

    Zhang, Hua; Shi, Yikai; Xu, Zhe

    2014-01-01

    X-ray cone-beam computed tomography (CT) has the notable features such as high efficiency and precision, and is widely used in the fields of medical imaging and industrial non-destructive testing, but the inherent imaging degradation reduces the quality of CT images. Aimed at the problems of projection images degradation and restoration in cone-beam CT, a point spread function (PSF) modeling method is proposed firstly. The general PSF model of cone-beam CT is established, and based on it, the PSF under arbitrary scanning conditions can be calculated directly for projection images restoration without the additional measurement, which greatly improved the application convenience of cone-beam CT. Secondly, a projection images restoration algorithm based on pre-filtering and pre-segmentation is proposed, which can make the edge contours in projection images and slice images clearer after restoration, and control the noise in the equivalent level to the original images. Finally, the experiments verified the feasib...

  19. Dark channel prior based blurred image restoration method using total variation and morphology

    Institute of Scientific and Technical Information of China (English)

    Yibing Li; Qiang Fu; Fang Ye; Hayaru Shouno

    2015-01-01

    The blurred image restoration method can dramatical y highlight the image details and enhance the global contrast, which is of benefit to improvement of the visual effect during practical ap-plications. This paper is based on the dark channel prior principle and aims at the prior information absent blurred image degradation situation. A lot of improvements have been made to estimate the transmission map of blurred images. Since the dark channel prior principle can effectively restore the blurred image at the cost of a large amount of computation, the total variation (TV) and image morphology transform (specifical y top-hat transform and bottom-hat transform) have been introduced into the improved method. Compared with original transmission map estimation methods, the proposed method features both simplicity and accuracy. The es-timated transmission map together with the element can restore the image. Simulation results show that this method could inhibit the il-posed problem during image restoration, meanwhile it can greatly improve the image quality and definition.

  20. GPU-based parallel algorithm for blind image restoration using midfrequency-based methods

    Science.gov (United States)

    Xie, Lang; Luo, Yi-han; Bao, Qi-liang

    2013-08-01

    GPU-based general-purpose computing is a new branch of modern parallel computing, so the study of parallel algorithms specially designed for GPU hardware architecture is of great significance. In order to solve the problem of high computational complexity and poor real-time performance in blind image restoration, the midfrequency-based algorithm for blind image restoration was analyzed and improved in this paper. Furthermore, a midfrequency-based filtering method is also used to restore the image hardly with any recursion or iteration. Combining the algorithm with data intensiveness, data parallel computing and GPU execution model of single instruction and multiple threads, a new parallel midfrequency-based algorithm for blind image restoration is proposed in this paper, which is suitable for stream computing of GPU. In this algorithm, the GPU is utilized to accelerate the estimation of class-G point spread functions and midfrequency-based filtering. Aiming at better management of the GPU threads, the threads in a grid are scheduled according to the decomposition of the filtering data in frequency domain after the optimization of data access and the communication between the host and the device. The kernel parallelism structure is determined by the decomposition of the filtering data to ensure the transmission rate to get around the memory bandwidth limitation. The results show that, with the new algorithm, the operational speed is significantly increased and the real-time performance of image restoration is effectively improved, especially for high-resolution images.

  1. Separated Component-Based Restoration of Speckled SAR Images

    Science.gov (United States)

    2014-01-01

    other documentation. 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS (ES) U.S. Army Research Office P.O. Box 12211 Research Triangle Park, NC...and Image Processing IX, 2001. [29] J.-F. Aujol, G. Aubert, L. Blanc- Fraud , and A. Chambolle, “Image decomposition application to SAR images,” in

  2. Preconditioned Iterative Methods for Algebraic Systems from Multiplicative Half-Quadratic Regularization Image Restorations

    Institute of Scientific and Technical Information of China (English)

    Zhong-Zhi; Yu-Mei; K.

    2010-01-01

    Image restoration is often solved by minimizing an energy function consisting of a data-fidelity term and a regularization term. A regularized convex term can usually preserve the image edges well in the restored image. In this paper, we consider a class of convex and edge-preserving regularization functions, I.e., multiplicative half-quadratic regularizations, and we use the Newton method to solve the correspondingly reduced systems of nonlinear equations. At each Newton iterate, the preconditioned conjugate gradient method, incorporated with a constraint preconditioner, is employed to solve the structured Newton equation that has a symmetric positive definite coefficient matrix.The igenvalue bounds of the preconditioned matrix are deliberately derived, which can be used to estimate the convergence speed of the preconditioned conjugate gradient method. We use experimental results to demonstrate that this new approach is efficient,and the effect of image restoration is r0easonably well.

  3. Particle Swarm Optimization Based Support Vector Regression for Blind Image Restoration

    Institute of Scientific and Technical Information of China (English)

    Ratnakar Dash; Pankaj Kumar Sa; Banshidhar Majhi

    2012-01-01

    This paper presents a swarm intelligence based parameter optimization of the support vector machine (SVM)for blind image restoration.In this work,SVM is used to solve a regression problem.Support vector regression (SVR)has been utilized to obtain a true mapping of images from the observed noisy blurred images.The parameters of SVR are optimized through particle swarm optimization (PSO) technique.The restoration error function has been utilized as the fitness function for PSO.The suggested scheme tries to adapt the SVM parameters depending on the type of blur and noise strength and the experimental results validate its effectiveness.The results show that the parameter optimization of the SVR model gives better performance than conventional SVR model as well as other competent schemes for blind image restoration.

  4. Bispectral methods of signal processing applications in radar, telecommunications and digital image restoration

    CERN Document Server

    Totsky, Alexander V; Kravchenko, Victor F

    2015-01-01

    By studying applications in radar, telecommunications and digital image restoration, this monograph discusses signal processing techniques based on bispectral methods. Improved robustness against different forms of noise as well as preservation of phase information render this method a valuable alternative to common power-spectrum analysis used in radar object recognition, digital wireless communications, and jitter removal in images.

  5. Enhancement of out-of-focus images using fusion-based PSF estimation and restoration

    Science.gov (United States)

    Yoon, Joonshik; Shin, Jeong-Ho; Paik, Joon-Ki

    2000-12-01

    In this paper, we propose an enhancement algorithm of out-of- focused images using fusion-based Point-spread-function (PSF) estimation and restoration. The proposed algorithm can make in-focused image by using only digital image processing techniques, and it requires neither infrared light/ultrasound nor focusing lens assembly operated by electrically powered movement of focusing lens. In order to increase accuracy in estimating the PSF of the defocus image, the proposed algorithm finds true and linear edges by using Canny edge detector, which is optimal edge detector and has good localization, estimates the step response across the edge for each pixel, computes the one-dimensional step response by averaging the step responses, estimates the two-dimensional PSF from the averaged step response, and then provides in- focused image by image restoration filter based on the estimated PSF. Finally, we execute fusion process, which can enhance the quality of the fused image by fusing restored images. There is a limit of the amount of out-of-focus, which can be recovered by the proposed algorithm. Moreover, the proposed algorithm is operating under assumption that an input image contains at least one piece-wise linear boundary between an object and background. In spite of above-mentioned limitations, the proposed algorithm can make acceptable quality of focused image by using only digital image processing.

  6. Restoration of digital images with known space-variant blurs from conventional optical systems

    Science.gov (United States)

    Costello, Thomas P.; Mikhael, Wasfy B.

    1999-07-01

    Space-variant (SV) digital image restoration methods attempt to restore images degraded by blurs that vary over the image field. One specific source of SV blurs is that of geometrical optical aberrations, which divert light rays as they pass through the optical system away from an ideal focal point. For simple optical system, aberrations can become significant even at moderate field angles. Restoration methods have been developed for some space- variant aberrations when they are individually dominant, but such dominance is not typically characteristic of conventional optical systems. In this paper, an iterative method of restoration that is applicable to generalized, known space-variant blurs is applied to simulations of images generated with a spherical lines. The method is based on the Gauss-Seidel method of solution to systems of linear equations. The method is applied to sub-images having off- axis displacements of up to 453 pixels, and found to be superior in restoration effectiveness to Fourier methods in that range of field angles.

  7. Digital imaging for cultural heritage preservation analysis, restoration, and reconstruction of ancient artworks

    CERN Document Server

    Stanco, Filippo; Gallo, Giovanni

    2011-01-01

    Experiencing the Past: Computer Graphics in Archaeology, F. Stanco and D. TanasiThe Past and the Future: Archaeology and Computer ScienceFrom the Field to the Screen: 3D computer graphics and the Archaeological HeritageThe Archeomatica ProjectArchaeological 3D ModelingHaghia Triada, CretePolizzello Mountain, SicilyDigital RestorationDealing with Image Data in Archaeology: New PerspectivesUsing Digital 3D Models for Study and Restoration of Cultural Heritage Artifacts, M.

  8. Separated Component-Based Restoration of Speckled SAR Images

    Science.gov (United States)

    2013-01-01

    This new process is also valuable for many SAR image understanding tasks such as road detection, railway detection, ship wake detection, texture...Starck, and L. Boubchir, “Morphological diversity and sparse image denoising,” in Proc. IEEE Int. Conf. Acoust . Speech Signal Process., vol. 1. Apr

  9. DEVELOPMENT OF OPTIMAL FILTERS OBTAINED THROUGH CONVOLUTION METHODS, USED FOR FINGERPRINT IMAGE ENHANCEMENT AND RESTORATION

    OpenAIRE

    Cătălin LUPU

    2014-01-01

    This article presents the development of optimal filters through covolution methods, necessary for restoring, correcting and improving fingerprints acquired from a sensor, able to provide the most ideal image in the output. After the image was binarized and equalized, Canny filter is applied in order to: eliminate the noise (filtering the image with a Gaussian filter), non-maxima suppression, module gradient adaptive binarization and extension edge points edges by hysteresis. The resulting i...

  10. DEVELOPMENT OF OPTIMAL FILTERS OBTAINED THROUGH CONVOLUTION METHODS, USED FOR FINGERPRINT IMAGE ENHANCEMENT AND RESTORATION

    OpenAIRE

    Cătălin LUPU

    2014-01-01

    This article presents the development of optimal filters through covolution methods, necessary for restoring, correcting and improving fingerprints acquired from a sensor, able to provide the most ideal image in the output. After the image was binarized and equalized, Canny filter is applied in order to: eliminate the noise (filtering the image with a Gaussian filter), non-maxima suppression, module gradient adaptive binarization and extension edge points edges by hysteresis. The resulting i...

  11. A NEW APPROACH FOR UNSUPERVISED RESTORING IMAGES BASED ON WAVELET-DOMAIN PROJECTION PURSUIT LEARNING NETWORK

    Institute of Scientific and Technical Information of China (English)

    Lin Wei; Tian Zheng; Wen Xianbin

    2003-01-01

    The Wavelet-Domain Projection Pursuit Learning Network (WDPPLN) is proposedfor restoring degraded image. The new network combines the advantages of both projectionpursuit and wavelet shrinkage. Restoring image is very difficult when little is known about apriori knowledge for multisource degraded factors. WDPPLN successfully resolves this problemby separately processing wavelet coefficients and scale coefficients. Parameters in WDPPLN,which are used to simulate degraded factors, are estimated via WDPPLN training, using scalecoefficients. Also, WDPPLN uses soft-threshold of wavelet shrinkage technique to suppress noisein three high frequency subbands. The new method is compared with the traditional methodsand the Projection Pursuit Learning Network (PPLN) method. Experimental results demonstratethat it is an effective method for unsupervised restoring degraded image.

  12. Robust low-dose dynamic cerebral perfusion CT image restoration via coupled dictionary learning scheme.

    Science.gov (United States)

    Tian, Xiumei; Zeng, Dong; Zhang, Shanli; Huang, Jing; Zhang, Hua; He, Ji; Lu, Lijun; Xi, Weiwen; Ma, Jianhua; Bian, Zhaoying

    2016-11-22

    Dynamic cerebral perfusion x-ray computed tomography (PCT) imaging has been advocated to quantitatively and qualitatively assess hemodynamic parameters in the diagnosis of acute stroke or chronic cerebrovascular diseases. However, the associated radiation dose is a significant concern to patients due to its dynamic scan protocol. To address this issue, in this paper we propose an image restoration method by utilizing coupled dictionary learning (CDL) scheme to yield clinically acceptable PCT images with low-dose data acquisition. Specifically, in the present CDL scheme, the 2D background information from the average of the baseline time frames of low-dose unenhanced CT images and the 3D enhancement information from normal-dose sequential cerebral PCT images are exploited to train the dictionary atoms respectively. After getting the two trained dictionaries, we couple them to represent the desired PCT images as spatio-temporal prior in objective function construction. Finally, the low-dose dynamic cerebral PCT images are restored by using a general DL image processing. To get a robust solution, the objective function is solved by using a modified dictionary learning based image restoration algorithm. The experimental results on clinical data show that the present method can yield more accurate kinetic enhanced details and diagnostic hemodynamic parameter maps than the state-of-the-art methods.

  13. Color Restoration of RGBN Multispectral Filter Array Sensor Images Based on Spectral Decomposition.

    Science.gov (United States)

    Park, Chulhee; Kang, Moon Gi

    2016-05-18

    A multispectral filter array (MSFA) image sensor with red, green, blue and near-infrared (NIR) filters is useful for various imaging applications with the advantages that it obtains color information and NIR information simultaneously. Because the MSFA image sensor needs to acquire invisible band information, it is necessary to remove the IR cut-offfilter (IRCF). However, without the IRCF, the color of the image is desaturated by the interference of the additional NIR component of each RGB color channel. To overcome color degradation, a signal processing approach is required to restore natural color by removing the unwanted NIR contribution to the RGB color channels while the additional NIR information remains in the N channel. Thus, in this paper, we propose a color restoration method for an imaging system based on the MSFA image sensor with RGBN filters. To remove the unnecessary NIR component in each RGB color channel, spectral estimation and spectral decomposition are performed based on the spectral characteristics of the MSFA sensor. The proposed color restoration method estimates the spectral intensity in NIR band and recovers hue and color saturation by decomposing the visible band component and the NIR band component in each RGB color channel. The experimental results show that the proposed method effectively restores natural color and minimizes angular errors.

  14. Restoration of images from the scanning-tunneling microscope

    Science.gov (United States)

    Kokaram, A. C.; Persad, N.; Lasenby, J.; Fitzgerald, W. J.; McKinnon, A.; Welland, M.

    1995-08-01

    During the acquisition of an image from any probe microscope instrument, various noise sources cause distortion in the observed image. It is often the case that impulsive disturbances cause bright groups of pixels to replace the actual image data in these locations. Furthermore, the images from a probe microscope show some amount of blurring caused both by the instrument function and the material properties. In almost all image-processing applications it is important to remove any impulsive distortion that may be present before deblurring can be attempted. We give a technique for detecting these impulses and reconstructing the image. This technique is superior to the standard global application of median filters for the case considered. The reconstruction is limited only to the affected regions and therefore results in a much sharper and more meaningful image. With the assumption of Gaussian blur it is then possible to propose several different deblurring methodologies. We present a novel Wiener-filter deblurring implementation and compare it to both maximum-entropy and Richardson-Lucy deblurring.

  15. A variational image restoration with spatially varying noise

    Science.gov (United States)

    Bao, Zheng; Bai, Hua; Liu, Ruihua; Shen, Chaomin

    2008-10-01

    The noise in natural images sometimes changes according to imaging mechanism or local image information. This is called spatially varying noise. It is obvious that classical variational denoising algorithms such as the Rudin-Osher-Fatemi model are not suitable for this kind of noise. We propose a variational method to remove this spatially varying noise based on the estimation of local variance for a given image, such that high noise regions are smoothed meanwhile the textures and certain details in low noise regions are preserved. Moreover, we give the proof of existence of the minimizer of our proposed functional. The experimental results show visual improvement and high signal-to-noise ratio over other variational denoising models.

  16. Restoration of polarimetric SAR images using simulated annealing

    DEFF Research Database (Denmark)

    Schou, Jesper; Skriver, Henning

    2001-01-01

    approach favoring one of the objectives. An algorithm for estimating the radar cross-section (RCS) for intensity SAR images has previously been proposed in the literature based on Markov random fields and the stochastic optimization method simulated annealing. A new version of the algorithm is presented...... are obtained while at the same time preserving most of the structures in the image. The algorithm is evaluated using multilook polarimetric L-band data from the Danish airborne EMISAR system, and the impact of the algorithm on the unsupervised H-α classification is demonstrated......Filtering synthetic aperture radar (SAR) images ideally results in better estimates of the parameters characterizing the distributed targets in the images while preserving the structures of the nondistributed targets. However, these objectives are normally conflicting, often leading to a filtering...

  17. Super-resolution image restoration algorithm based on orthogonal discrete wavelet transform

    Institute of Scientific and Technical Information of China (English)

    Yangyang Liu(刘扬阳); Weiqi Jin(金伟其); Binghua Su(苏秉华)

    2004-01-01

    By using orthogonal discrete wavelet transform(ODWT)and generalized cross validation(GCV),and combining with Luck-Richardson algorithm based on Poisson-Markovmodel (MPML),several new superresolution image restoration algorithms are proposed.According to simulation experiments for practical images,all the proposed algor ithms could retain image details better than MPML,and be more suitable to low signal-to-noise ratio(SNR)images.The single operation wavelet MPML(SW-MPML)algorithm and MPML algorithm based on single operation wavelet transform(MPML-SW)avoid the iterative operation of self-adaptive parameter in MPML particularly,and improve operating speed and precision.They are instantaneous to super-resolution image restoration process and have extensive application foreground.

  18. Iterative Desensitisation of Image Restoration Filters under Wrong PSF and Noise Estimates

    Directory of Open Access Journals (Sweden)

    Bernués Emiliano

    2007-01-01

    Full Text Available The restoration achieved on the basis of a Wiener scheme is an optimum since the restoration filter is the outcome of a minimisation process. Moreover, the Wiener restoration approach requires the estimation of some parameters related to the original image and the noise, as well as knowledge about the PSF function. However, in a real restoration problem, we may not possess accurate values of these parameters, making results relatively far from the desired optimum. Indeed, a desensitisation process is required to decrease this dependency on the parameter errors of the restoration filter. In this paper, we present an iterative method to reduce the sensitivity of a general restoration scheme (but specified to the Wiener filter with regards to wrong estimates of the said parameters. Within the Fourier transform domain, a sensitivity analysis is tackled in depth with the purpose of defining a number of iterations for each frequency element, which leads to the aimed desensitisation regardless of the errors on estimates. Experimental computations using meaningful values of parameters are addressed. The proposed technique effectively achieves better results than those obtained when using the same wrong estimates in the Wiener approach, as well as verified on an SAR restoration.

  19. Image restoration using regularized inverse filtering and adaptive threshold wavelet denoising

    Directory of Open Access Journals (Sweden)

    Mr. Firas Ali

    2007-01-01

    Full Text Available Although the Wiener filtering is the optimal tradeoff of inverse filtering and noise smoothing, in the case when the blurring filter is singular, the Wiener filtering actually amplify the noise. This suggests that a denoising step is needed to remove the amplified noise .Wavelet-based denoising scheme provides a natural technique for this purpose .In this paper a new image restoration scheme is proposed, the scheme contains two separate steps : Fourier-domain inverse filtering and wavelet-domain image denoising. The first stage is Wiener filtering of the input image , the filtered image is inputted to adaptive threshold wavelet denoising stage . The choice of the threshold estimation is carried out by analyzing the statistical parameters of the wavelet sub band coefficients like standard deviation, arithmetic mean and geometrical mean . The noisy image is first decomposed into many levels to obtain different frequency bands. Then soft thresholding method is used to remove the noisy coefficients, by fixing the optimum thresholding value by this method .Experimental results on test image by using this method show that this method yields significantly superior image quality and better Peak Signal to Noise Ratio (PSNR. Here, to prove the efficiency of this method in image restoration , we have compared this with various restoration methods like Wiener filter alone and inverse filter.

  20. Radiopacity of restorative composites by conventional radiography and digital images with different resolutions

    Energy Technology Data Exchange (ETDEWEB)

    Dantas, Raquel Venancio; Samento, Hugo Ramalho [Graduate Program in Dentistry, Federal University of Pelotas, Pelotas (Brazil); Duarte, Rosangela Marques; Raso, Sonia Saeger Meireles Monte; De Andrade Ana Karina Maciel; Anjos-Pontual Maria Luiza Dos [Dept. of Operative Dentistry, Federal University of Paraiba, Pelotas (Brazil)

    2013-09-15

    This study was performed to evaluate and compare the radiopacity of dentin, enamel, and 8 restorative composites on conventional radiograph and digital images with different resolutions. Specimens were fabricated from 8 materials and human molars were longitudinally sectioned 1.0 mm thick to include both enamel and dentin. The specimens and tooth sections were imaged by conventional radiograph using 4 sized intraoral film and digital images were taken in high speed and high resolution modes using a phosphor storage plate. Densitometric evaluation of the enamel, dentin, restorative materials, a lead sheet, and an aluminum step wedge was performed on the radiographic images. For the evaluation, the Al equivalent (mm) for each material was calculated. The data were analyzed using one-way ANOVA and Tukey's test (p<0.05), considering the material factor and then the radiographic method factor, individually. The high speed mode allowed the highest radiopacity, while the high resolution mode generated the lowest values. Furthermore, the high resolution mode was the most efficient method for radiographic differentiation between restorative composites and dentin. The conventional radiograph was the most effective in enabling differentiation between enamel and composites. The high speed mode was the least effective in enabling radiographic differentiation between the dental tissues and restorative composites. The high speed mode of digital imaging was not effective for differentiation between enamel and composites. This made it less effective than the high resolution mode and conventional radiographs. All of the composites evaluated showed radiopacity values that fit the ISO 4049 recommendations.

  1. Blurred image restoration using the type of blur and blur parameter identification on the neural network

    Science.gov (United States)

    Aizenberg, Igor N.; Butakoff, Constantine; Karnaukhov, Viktor N.; Merzlyakov, Nikolay S.; Milukova, Olga

    2002-05-01

    As a rule, blur is a form of bandwidth reduction of an ideal image owing to the imperfect image formation process. It can be caused by relative motion between the camera and the original scene, or by an optical system that is out of focus. Today there are different techniques available for solving of the restoration problem including Fourier domain techniques, regularization methods, recursive and iterative filters to name a few. But without knowing at least approximate parameters of the blur, these filters show poor results. If incorrect blur model is chosen then the image will be rather distorted much more than restored. The original solution of the blur and blur parameters identification problem is presented in this paper. A neural network based on multi-valued neurons is used for the blur and blur parameters identification. It is shown that using simple single-layered neural network it is possible to identify the type of the distorting operator. Four types of blur are considered: defocus, rectangular, motion and Gaussian ones. The parameters of the corresponding operator are identified using a similar neural network. After a type of blur and its parameters identification the image can be restored using several kinds of methods. Some fundamentals of image restoration are also considered.

  2. Wavelet-Based Diffusion Approach for DTI Image Restoration

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiang-fen; CHEN Wu-fan; TIAN Wei-feng; YE Hong

    2008-01-01

    The Rician noise introduced into the diffusion tensor images (DTIs) can bring serious impacts on tensor calculation and fiber tracking. To decrease the effects of the Rician noise, we propose to consider the wavelet-based diffusion method to denoise multichannel typed diffusion weighted (DW) images. The presented smoothing strategy, which utilizes anisotropic nonlinear diffusion in wavelet domain, successfully removes noise while preserving both texture and edges. To evaluate quantitatively the efficiency of the presented method in accounting for the Rician noise introduced into the DW images, the peak-to-peak signal-to-noise ratio (PSNR) and signal-to-mean squared error ratio (SMSE) metrics are adopted. Based on the synthetic and real data, we calculated the apparent diffusion coefficient (ADC) and tracked the fibers. We made comparisons between the presented model,the wave shrinkage and regularized nonlinear diffusion smoothing method. All the experiment results prove quantitatively and visually the better performance of the presented filter.

  3. Virtual restoration of cracks in digitized image of paintings

    Energy Technology Data Exchange (ETDEWEB)

    Spagnolo, G Schirripa; Somma, F

    2010-11-01

    An integrated methodology for the detection and removal of cracks on digitized image is presented in this paper. Crack-like pattern detection have been a matter of high concern among researchers mostly for its useful contribution to a variety of applications. The results presented here regard the craquelure of old paintings, however, the same methodology can be used for a much wider set of application. Many images contain similar patterns: crack in protective coating for polymers and other surfaces; fatigue crack in MEMS/NEMS; crack in epoxies used for underfill and encapsulation microelectronics components; etc. In this paper the cracks are detected by thresholding the output of the morphological top-hat transform. Afterwards, the thin dark brush strokes which have been misidentified as cracks are removed using automatic procedure. Finally, crack filling using texture synthesis algorithms. The methodology has been shown to perform very well on digitized images suffering from cracks.

  4. Wavefront Control and Image Restoration with Less Computing

    Science.gov (United States)

    Lyon, Richard G.

    2010-01-01

    PseudoDiversity is a method of recovering the wavefront in a sparse- or segmented- aperture optical system typified by an interferometer or a telescope equipped with an adaptive primary mirror consisting of controllably slightly moveable segments. (PseudoDiversity should not be confused with a radio-antenna-arraying method called pseudodiversity.) As in the cases of other wavefront- recovery methods, the streams of wavefront data generated by means of PseudoDiversity are used as feedback signals for controlling electromechanical actuators of the various segments so as to correct wavefront errors and thereby, for example, obtain a clearer, steadier image of a distant object in the presence of atmospheric turbulence. There are numerous potential applications in astronomy, remote sensing from aircraft and spacecraft, targeting missiles, sighting military targets, and medical imaging (including microscopy) through such intervening media as cells or water. In comparison with prior wavefront-recovery methods used in adaptive optics, PseudoDiversity involves considerably simpler equipment and procedures and less computation. For PseudoDiversity, there is no need to install separate metrological equipment or to use any optomechanical components beyond those that are already parts of the optical system to which the method is applied. In Pseudo- Diversity, the actuators of a subset of the segments or subapertures are driven to make the segments dither in the piston, tilt, and tip degrees of freedom. Each aperture is dithered at a unique frequency at an amplitude of a half wavelength of light. During the dithering, images on the focal plane are detected and digitized at a rate of at least four samples per dither period. In the processing of the image samples, the use of different dither frequencies makes it possible to determine the separate effects of the various dithered segments or apertures. The digitized image-detector outputs are processed in the spatial

  5. Variational approach for restoring blurred images with cauchy noise

    DEFF Research Database (Denmark)

    Sciacchitano, Federica; Dong, Yiqiu; Zeng, Tieyong

    2015-01-01

    model, we add a quadratic penalty term, which guarantees the uniqueness of the solution. Due to the convexity of our model, the primal dual algorithm is employed to solve the minimization problem. Experimental results show the effectiveness of the proposed method for simultaneously deblurring...... and denoising images corrupted by Cauchy noise. Comparison with other existing and well-known methods is provided as well....

  6. Super-resolution image restoration algorithms based on orthogonal discrete wavelet transform

    Science.gov (United States)

    Liu, Yang-yang; Jin, Wei-qi

    2005-02-01

    Several new super-resolution image restoration algorithms based on orthogonal discrete wavelet transform are proposed, by using orthogonal discrete wavelet transform and generalized cross validation ,and combining with Luck-Richardson super-resolution image restoration algorithm (LR) and Luck-Richardson algorithm based on Poisson-Markov model (MPML). Orthogonal discrete wavelet transform analyzed in both space and frequency domain has the capability of indicating local features of a signal, and concentrating the signal power to a few coefficients in wavelet transform domain. After an original image is "Symlets" orthogonal discrete wavelet transformed, an asymptotically optimal threshold is determined by minimizing generalized cross validation, and high frequency subbands in each decomposition level are denoised with soft threshold processes to converge respectively to those with maximum signal-noise-ratio, when the method is incorporated with existed super-resolution image algorithms, details of original image, especially of those with low signal-noise-ratio, could be well recovered. Single operation wavelet LR algorithm(SWLR),single operation wavelet MPML algorithm(SW-MPML) and MPML algorithm based on single operation and wavelet transform (MPML- SW) are some operative algorithms proposed based on the method. According to the processing results to simulating and practical images , because of the only one operation, under the guarantee of rapid and effective restoration processing, in comparison with LR and MPML, all the proposed algorithms could retain image details better, and be more suitable to low signal-noise-ratio images, They could also reduce operation time for up to hundreds times of iteratives, as well as, avoid the iterative operation of self-adaptive parameters in MPML, improve operating speed and precision. They are practical and instantaneous to some extent in the field of low signal-noise-ratio image restoration.

  7. Full-field optical coherence tomography image restoration based on Hilbert transformation

    Science.gov (United States)

    Na, Jihoon; Choi, Woo June; Choi, Eun Seo; Ryu, Seon Young; Lee, Byeong Ha

    2007-02-01

    We propose the envelope detection method that is based on Hilbert transform for image restoration in full-filed optical coherence tomography (FF-OCT). The FF-OCT system presenting a high-axial resolution of 0.9 μm was implemented with a Kohler illuminator based on Linnik interferometer configuration. A 250 W customized quartz tungsten halogen lamp was used as a broadband light source and a CCD camera was used as a 2-dimentional detector array. The proposed image restoration method for FF-OCT requires only single phase-shifting. By using both the original and the phase-shifted images, we could remove the offset and the background signals from the interference fringe images. The desired coherent envelope image was obtained by applying Hilbert transform. With the proposed image restoration method, we demonstrate en-face imaging performance of the implemented FF-OCT system by presenting a tilted mirror surface, an integrated circuit chip, and a piece of onion epithelium.

  8. Compressive Sensing Image Restoration Using Adaptive Curvelet Thresholding and Nonlocal Sparse Regularization.

    Science.gov (United States)

    Eslahi, Nasser; Aghagolzadeh, Ali

    2016-07-01

    Compressive sensing (CS) is a recently emerging technique and an extensively studied problem in signal and image processing, which suggests a new framework for the simultaneous sampling and compression of sparse or compressible signals at a rate significantly below the Nyquist rate. Maybe, designing an effective regularization term reflecting the image sparse prior information plays a critical role in CS image restoration. Recently, both local smoothness and nonlocal self-similarity have led to superior sparsity prior for CS image restoration. In this paper, first, an adaptive curvelet thresholding criterion is developed, trying to adaptively remove the perturbations appeared in recovered images during CS recovery process, imposing sparsity. Furthermore, a new sparsity measure called joint adaptive sparsity regularization (JASR) is established, which enforces both local sparsity and nonlocal 3-D sparsity in transform domain, simultaneously. Then, a novel technique for high-fidelity CS image recovery via JASR is proposed-CS-JASR. To efficiently solve the proposed corresponding optimization problem, we employ the split Bregman iterations. Extensive experimental results are reported to attest the adequacy and effectiveness of the proposed method comparing with the current state-of-the-art methods in CS image restoration.

  9. ASSESSMENT OF RESTORATION METHODS OF X-RAY IMAGES WITH EMPHASIS ON MEDICAL PHOTOGRAMMETRIC USAGE

    Directory of Open Access Journals (Sweden)

    S. Hosseinian

    2016-06-01

    Full Text Available Nowadays, various medical X-ray imaging methods such as digital radiography, computed tomography and fluoroscopy are used as important tools in diagnostic and operative processes especially in the computer and robotic assisted surgeries. The procedures of extracting information from these images require appropriate deblurring and denoising processes on the pre- and intra-operative images in order to obtain more accurate information. This issue becomes more considerable when the X-ray images are planned to be employed in the photogrammetric processes for 3D reconstruction from multi-view X-ray images since, accurate data should be extracted from images for 3D modelling and the quality of X-ray images affects directly on the results of the algorithms. For restoration of X-ray images, it is essential to consider the nature and characteristics of these kinds of images. X-ray images exhibit severe quantum noise due to limited X-ray photons involved. The assumptions of Gaussian modelling are not appropriate for photon-limited images such as X-ray images, because of the nature of signal-dependant quantum noise. These images are generally modelled by Poisson distribution which is the most common model for low-intensity imaging. In this paper, existing methods are evaluated. For this purpose, after demonstrating the properties of medical X-ray images, the more efficient and recommended methods for restoration of X-ray images would be described and assessed. After explaining these approaches, they are implemented on samples from different kinds of X-ray images. By considering the results, it is concluded that using PURE-LET, provides more effective and efficient denoising than other examined methods in this research.

  10. Assessment of Restoration Methods of X-Ray Images with Emphasis on Medical Photogrammetric Usage

    Science.gov (United States)

    Hosseinian, S.; Arefi, H.

    2016-06-01

    Nowadays, various medical X-ray imaging methods such as digital radiography, computed tomography and fluoroscopy are used as important tools in diagnostic and operative processes especially in the computer and robotic assisted surgeries. The procedures of extracting information from these images require appropriate deblurring and denoising processes on the pre- and intra-operative images in order to obtain more accurate information. This issue becomes more considerable when the X-ray images are planned to be employed in the photogrammetric processes for 3D reconstruction from multi-view X-ray images since, accurate data should be extracted from images for 3D modelling and the quality of X-ray images affects directly on the results of the algorithms. For restoration of X-ray images, it is essential to consider the nature and characteristics of these kinds of images. X-ray images exhibit severe quantum noise due to limited X-ray photons involved. The assumptions of Gaussian modelling are not appropriate for photon-limited images such as X-ray images, because of the nature of signal-dependant quantum noise. These images are generally modelled by Poisson distribution which is the most common model for low-intensity imaging. In this paper, existing methods are evaluated. For this purpose, after demonstrating the properties of medical X-ray images, the more efficient and recommended methods for restoration of X-ray images would be described and assessed. After explaining these approaches, they are implemented on samples from different kinds of X-ray images. By considering the results, it is concluded that using PURE-LET, provides more effective and efficient denoising than other examined methods in this research.

  11. Projection based image restoration, super-resolution and error correction codes

    Science.gov (United States)

    Bauer, Karl Gregory

    Super-resolution is the ability of a restoration algorithm to restore meaningful spatial frequency content beyond the diffraction limit of the imaging system. The Gerchberg-Papoulis (GP) algorithm is one of the most celebrated algorithms for super-resolution. The GP algorithm is conceptually simple and demonstrates the importance of using a priori information in the formation of the object estimate. In the first part of this dissertation the continuous GP algorithm is discussed in detail and shown to be a projection on convex sets algorithm. The discrete GP algorithm is shown to converge in the exactly-, over- and under-determined cases. A direct formula for the computation of the estimate at the kth iteration and at convergence is given. This analysis of the discrete GP algorithm sets the stage to connect super-resolution to error-correction codes. Reed-Solomon codes are used for error-correction in magnetic recording devices, compact disk players and by NASA for space communications. Reed-Solomon codes have a very simple description when analyzed with the Fourier transform. This signal processing approach to error- correction codes allows the error-correction problem to be compared with the super-resolution problem. The GP algorithm for super-resolution is shown to be equivalent to the correction of errors with a Reed-Solomon code over an erasure channel. The Restoration from Magnitude (RFM) problem seeks to recover a signal from the magnitude of the spectrum. This problem has applications to imaging through a turbulent atmosphere. The turbulent atmosphere causes localized changes in the index of refraction and introduces different phase delays in the data collected. Synthetic aperture radar (SAR) and hyperspectral imaging systems are capable of simultaneously recording multiple images of different polarizations or wavelengths. Each of these images will experience the same turbulent atmosphere and have a common phase distortion. A projection based restoration

  12. Computationally efficient image restoration and super-resolution algorithns for real-time implementation

    Science.gov (United States)

    Sundareshan, Malur K.

    2002-07-01

    Computational complexity is a major impediment to the real- time implementation of image restoration and super- resolution algorithms. Although powerful restoration algorithms have been developed within the last few years utilizing sophisticated mathematical machinery (based on statistical optimization and convex set theory), these algorithms are typically iterative in nature and require enough number of iterations to be executed to achieve desired resolution gains in order to meaningfully perform detection and recognition tasks in practice. Additionally, recent technological breakthroughs have facilitated novel sensor designs (focal plane arrays, for instance) that make it possible to capture mega-pixel imagery data at video frame rates. A major challenge in the processing of these large format images is to complete the execution of the image processing steps within the frame capture times and to keep up with the output rate of the sensor so that all data captured by the sensor can be efficiently utilized. Consequently, development of novel methods that facilitate real-time implementation of image restoration and super- resolution algorithms is of significant practical interest and will be the primary focus of this paper. The key to designing computationally efficient processing schemes lies in strategically introducing appropriate pre-processing and post-processing steps together with the super-resolution iterations in order to tailor optimized overall processing sequences for imagery data of specific formats. Three distinct methods for tailoring a pre-processing filter and integrating it with the super-resolution processing steps will be outlined in this paper. These methods consist of a Region-of-Interest (ROI) extraction scheme, a background- detail separation procedure, and a scene-derived information extraction step for implementing a set-theoretic restoration of the image that is less demanding in computation compared to the super-resolution iterations. A

  13. Image preprocessing for improving computational efficiency in implementation of restoration and superresolution algorithms.

    Science.gov (United States)

    Sundareshan, Malur K; Bhattacharjee, Supratik; Inampudi, Radhika; Pang, Ho-Yuen

    2002-12-10

    Computational complexity is a major impediment to the real-time implementation of image restoration and superresolution algorithms in many applications. Although powerful restoration algorithms have been developed within the past few years utilizing sophisticated mathematical machinery (based on statistical optimization and convex set theory), these algorithms are typically iterative in nature and require a sufficient number of iterations to be executed to achieve the desired resolution improvement that may be needed to meaningfully perform postprocessing image exploitation tasks in practice. Additionally, recent technological breakthroughs have facilitated novel sensor designs (focal plane arrays, for instance) that make it possible to capture megapixel imagery data at video frame rates. A major challenge in the processing of these large-format images is to complete the execution of the image processing steps within the frame capture times and to keep up with the output rate of the sensor so that all data captured by the sensor can be efficiently utilized. Consequently, development of novel methods that facilitate real-time implementation of image restoration and superresolution algorithms is of significant practical interest and is the primary focus of this study. The key to designing computationally efficient processing schemes lies in strategically introducing appropriate preprocessing steps together with the superresolution iterations to tailor optimized overall processing sequences for imagery data of specific formats. For substantiating this assertion, three distinct methods for tailoring a preprocessing filter and integrating it with the superresolution processing steps are outlined. These methods consist of a region-of-interest extraction scheme, a background-detail separation procedure, and a scene-derived information extraction step for implementing a set-theoretic restoration of the image that is less demanding in computation compared with the

  14. Image preprocessing for improving computational efficiency in implementation of restoration and superresolution algorithms

    Science.gov (United States)

    Sundareshan, Malur K.; Bhattacharjee, Supratik; Inampudi, Radhika; Pang, Ho-Yuen

    2002-12-01

    Computational complexity is a major impediment to the real-time implementation of image restoration and superresolution algorithms in many applications. Although powerful restoration algorithms have been developed within the past few years utilizing sophisticated mathematical machinery (based on statistical optimization and convex set theory), these algorithms are typically iterative in nature and require a sufficient number of iterations to be executed to achieve the desired resolution improvement that may be needed to meaningfully perform postprocessing image exploitation tasks in practice. Additionally, recent technological breakthroughs have facilitated novel sensor designs (focal plane arrays, for instance) that make it possible to capture megapixel imagery data at video frame rates. A major challenge in the processing of these large-format images is to complete the execution of the image processing steps within the frame capture times and to keep up with the output rate of the sensor so that all data captured by the sensor can be efficiently utilized. Consequently, development of novel methods that facilitate real-time implementation of image restoration and superresolution algorithms is of significant practical interest and is the primary focus of this study. The key to designing computationally efficient processing schemes lies in strategically introducing appropriate preprocessing steps together with the superresolution iterations to tailor optimized overall processing sequences for imagery data of specific formats. For substantiating this assertion, three distinct methods for tailoring a preprocessing filter and integrating it with the superresolution processing steps are outlined. These methods consist of a region-of-interest extraction scheme, a background-detail separation procedure, and a scene-derived information extraction step for implementing a set-theoretic restoration of the image that is less demanding in computation compared with the

  15. Adaptive contourlet-wavelet iterative shrinkage/thresholding for remote sensing image restoration

    Institute of Scientific and Technical Information of China (English)

    Nu WEN; Shi-zhi YANG; Cheng-jie ZHU; Sheng-cheng CUI

    2014-01-01

    In this paper, we present an adaptive two-step contourlet-wavelet iterative shrinkage/thresholding (TcwIST) algorithm for remote sensing image restoration. This algorithm can be used to deal with various linear inverse problems (LIPs), including image deconvolution and reconstruction. This algorithm is a new version of the famous two-step iterative shrinkage/thresholding (TwIST) algorithm. First, we use the split Bregman Rudin-Osher-Fatemi (ROF) model, based on a sparse dictionary, to decom-pose the image into cartoon and texture parts, which are represented by wavelet and contourlet, respectively. Second, we use an adaptive method to estimate the regularization parameter and the shrinkage threshold. Finally, we use a linear search method to find a step length and a fast method to accelerate convergence. Results show that our method can achieve a signal-to-noise ratio improvement (ISNR) for image restoration and high convergence speed.

  16. Image restoration techniques based on fuzzy neural networks

    Institute of Scientific and Technical Information of China (English)

    刘普寅; 李洪兴

    2002-01-01

    By establishing some suitable partitions of input and output spaces, a novel fuzzy neuralnetwork (FNN) which is called selection type FNN is developed. Such a system is a multilayerfeedforward neural network, which can be a universal approximator with maximum norm. Based ona family of fuzzy inference rules that are of real senses, a simple and useful inference type FNN isconstructed. As a result, the fusion of selection type FNN and inference type FNN results in a novelfilter-FNN filter. It is simple in structure. And also it is convenient to design the learning algorithmfor structural parameters. Further, FNN filter can efficiently suppress impulse noise superimposed onimage and preserve fine image structure, simultaneously. Some examples are simulated to confirmthe advantages of FNN filter over other filters, such as median filter and adaptive weighted fuzzymean (AWFM) filter and so on, in suppression of noises and preservation of image structure.

  17. A Convex Variational Model for Restoring Blurred Images with Multiplicative Noise

    DEFF Research Database (Denmark)

    Dong, Yiqiu; Tieyong Zeng

    2013-01-01

    In this paper, a new variational model for restoring blurred images with multiplicative noise is proposed. Based on the statistical property of the noise, a quadratic penalty function technique is utilized in order to obtain a strictly convex model under a mild condition, which guarantees...... to multiplicative noise. A comparison with other methods is provided as well....

  18. Robust Image Restoration for Ground-Based Space Surveillance

    Science.gov (United States)

    2013-09-01

    the Earth’s atmosphere requires careful mitigation of the turbulence-induced aberration in the observed wave fronts. This is typically achieved...BACKGROUND As we discuss in Jefferies et al. [3], high spatial frequency aberrations of the wave-front phase become increasingly damaging to image...large values of D/r0 where chromatic radial streaking of the PSF speckles is a large part of the PSF morphology. By including temporal and spectral

  19. The trustworthy digital camera: Restoring credibility to the photographic image

    Science.gov (United States)

    Friedman, Gary L.

    1994-02-01

    The increasing sophistication of computers has made digital manipulation of photographic images, as well as other digitally-recorded artifacts such as audio and video, incredibly easy to perform and increasingly difficult to detect. Today, every picture appearing in newspapers and magazines has been digitally altered to some degree, with the severity varying from the trivial (cleaning up 'noise' and removing distracting backgrounds) to the point of deception (articles of clothing removed, heads attached to other people's bodies, and the complete rearrangement of city skylines). As the power, flexibility, and ubiquity of image-altering computers continues to increase, the well-known adage that 'the photography doesn't lie' will continue to become an anachronism. A solution to this problem comes from a concept called digital signatures, which incorporates modern cryptographic techniques to authenticate electronic mail messages. 'Authenticate' in this case means one can be sure that the message has not been altered, and that the sender's identity has not been forged. The technique can serve not only to authenticate images, but also to help the photographer retain and enforce copyright protection when the concept of 'electronic original' is no longer meaningful.

  20. Image-restoration algorithms for a fully connected architecture.

    Science.gov (United States)

    Abbiss, J B; Brames, B J; Byrne, C L; Fiddy, M A

    1990-06-15

    We describe the implementation of a technique for achieving image superresolution using a fully connected network of simple processors operating in an iterative mode. We show that an updating scheme can be specified that ensures convergence for the serial (asynchronous) updating case. With the appropriate hardware, parallel (synchronous) updating becomes of particular interest because of the potential for accelerated convergence; it is this approach that we envisage implementing in optical hardware. For this case also, we present a convergent scheme that can be related to a regularized form of the Gerchberg-Papoulis algorithm.

  1. TV-Based Caring Videophone System for the Elderly in the Smart Home Environment

    Directory of Open Access Journals (Sweden)

    Jingshuang Shen

    2013-01-01

    Full Text Available A novel videophone system for the elderly-care application is proposed. Based on the detailed analysis of the elderly’s physical and psychological characteristics, a TV-based caring videophone system for the elderly is developed: an embedded multimedia device is designed to implement the interactive video and audio processing and IP-based communication, in which TV is adopted as the display terminal to achieve a low-cost but high-quality service. Considering the user’s convenience, many personalized designs, such as photo-based address book, photo-click-dialing, and touch pad based remote controller, are developed to make the proposed videophone system more intuitive and easy to use for the elderly. Based on Support Vector Machine (SVM algorithms, an evaluation model is also developed with the data collected from the embedded multimedia device. It is useful to evaluate the physical and psychological health of the elderly.

  2. An edge-preserving algorithm of joint image restoration and volume reconstruction for rotation-scanning 4D echocardiographic images

    Institute of Scientific and Technical Information of China (English)

    GUO Qiang; YANG Xin

    2006-01-01

    A statistical algorithm for the reconstruction from time sequence echocardiographic images is proposed in this paper.The ability to jointly restore the images and reconstruct the 3D images without blurring the boundary is the main innovation of this algorithm. First, a Bayesian model based on MAP-MRF is used to reconstruct 3D volume, and extended to deal with the images acquired by rotation scanning method. Then, the spatiotemporal nature of ultrasound images is taken into account for the parameter of energy function, which makes this statistical model anisotropic. Hence not only can this method reconstruct 3D ultrasound images, but also remove the speckle noise anisotropically. Finally, we illustrate the experiments of our method on the synthetic and medical images and compare it with the isotropic reconstruction method.

  3. An improved method for polarimetric image restoration in interferometry

    CERN Document Server

    Pratley, Luke

    2016-01-01

    Interferometric radio astronomy data require the effects of limited coverage in the Fourier plane to be accounted for via a deconvolution process. For the last 40 years this process, known as `cleaning', has been performed almost exclusively on all Stokes parameters individually as if they were independent scalar images. However, here we demonstrate for the case of the linear polarisation $\\mathcal{P}$, this approach fails to properly account for the complex vector nature resulting in a process which is dependant on the axis under which the deconvolution is performed. We present here an improved method, `Generalised Complex CLEAN', which properly accounts for the complex vector nature of polarised emission and is invariant under rotations of the deconvolution axis. We use two Australia Telescope Compact Array datasets to test standard and complex CLEAN versions of the H\\"{o}gbom and SDI CLEAN algorithms. We show that in general the Complex CLEAN version of each algorithm produces more accurate clean component...

  4. An improved method for polarimetric image restoration in interferometry

    Science.gov (United States)

    Pratley, Luke; Johnston-Hollitt, Melanie

    2016-11-01

    Interferometric radio astronomy data require the effects of limited coverage in the Fourier plane to be accounted for via a deconvolution process. For the last 40 years this process, known as `cleaning', has been performed almost exclusively on all Stokes parameters individually as if they were independent scalar images. However, here we demonstrate for the case of the linear polarization P, this approach fails to properly account for the complex vector nature resulting in a process which is dependent on the axes under which the deconvolution is performed. We present here an improved method, `Generalized Complex CLEAN', which properly accounts for the complex vector nature of polarized emission and is invariant under rotations of the deconvolution axes. We use two Australia Telescope Compact Array data sets to test standard and complex CLEAN versions of the Högbom and SDI (Steer-Dwedney-Ito) CLEAN algorithms. We show that in general the complex CLEAN version of each algorithm produces more accurate clean components with fewer spurious detections and lower computation cost due to reduced iterations than the current methods. In particular, we find that the complex SDI CLEAN produces the best results for diffuse polarized sources as compared with standard CLEAN algorithms and other complex CLEAN algorithms. Given the move to wide-field, high-resolution polarimetric imaging with future telescopes such as the Square Kilometre Array, we suggest that Generalized Complex CLEAN should be adopted as the deconvolution method for all future polarimetric surveys and in particular that the complex version of an SDI CLEAN should be used.

  5. Remotely sensed image restoration using partial differential equations and watershed transformation

    Science.gov (United States)

    Nazari, Avishan; Zehtabian, Amin; Gribaudo, Marco; Ghassemian, Hassan

    2015-02-01

    This paper proposes a novel approach for remotely sensed image restoration. The main goal of this study is to mitigate two most well-known types of noises from remote sensing images while their important details such as edges are preserved. To this end, a novel method based on partial differential equations is proposed. The parameters used in the proposed algorithm are adaptively set regarding the type of noise and the texture of noisy datasets. Moreover, we propose to apply a segmentation pre-processing step based on Watershed transformation to localize the denoising process. The performance of the restoration techniques is measured using PSNR criterion. For further assessment, we also feed the original/noisy/denoised images into SVM classifier and explore the results.

  6. Improving spatial resolution of confocal Raman microscopy by super-resolution image restoration.

    Science.gov (United States)

    Cui, Han; Zhao, Weiqian; Wang, Yun; Fan, Ying; Qiu, Lirong; Zhu, Ke

    2016-05-16

    A new super-resolution image restoration confocal Raman microscopy method (SRIR-RAMAN) is proposed for improving the spatial resolution of confocal Raman microscopy. This method can recover the lost high spatial frequency of the confocal Raman microscopy by using Poisson-MAP super-resolution imaging restoration, thereby improving the spatial resolution of confocal Raman microscopy and realizing its super-resolution imaging. Simulation analyses and experimental results indicate that the spatial resolution of SRIR-RAMAN can be improved by 65% to achieve 200 nm with the same confocal Raman microscopy system. This method can provide a new tool for high spatial resolution micro-probe structure detection in physical chemistry, materials science, biomedical science and other areas.

  7. A Comparison of Solar Image Restoration Techniques for SST/CRISP Data (Summary)

    Science.gov (United States)

    Löfdahl, M.

    2016-04-01

    Solar images from high-resolution, ground-based telescopes are corrected for the blurring effects of atmospheric turbulence by use of adaptive optics and post-facto image restoration. Two classes of image restoration methods are regularly used today, those based on Multi-Frame Blind Deconvolution (MFBD; Löfdahl 2002) and those based on Speckle Interferometry (SI; von der Luhe &Dunn 1987). In a recently started project, we will compare and evaluate such methods for use with spectropolarimetric data from the CRisp Imaging SpectroPolarimeter (CRISP; Scharmer et al. 2008) of the Swedish 1-meter Solar Telescope (SST; Scharmer et al. 2003). For SST/CRISP data we routinely use the Multi-Object MFBD (MOMFBD; van Noort et al. 2005) technique to jointly restore images collected from a wideband camera and from the narrowband cameras behind the CRISP FPI and polarimetry optics. This crucial step in the data reduction pipeline of CRISP (CRISPRED; de la Cruz Rodríguez et al. 2015) is carefully integrated with the application of various procedures that are designed to reduce effects of imperfections in the instruments. In order to make the comparison as fair as possible, we have extended CRISPRED so that the Kiepenheuer-Institut Speckle Interferometry Package (KISIP; Wöger & von der Lühe 2008), together with Speckle Deconvolution (SD; Keller & von der Luehe 1992; Mikurda et al. 2006), can serve as a drop in replacement for MOMFBD. The adaption of SI and SD to CRISPRED will allow us to make fair comparisons not only of the restored images, but also of derivative data like Stokes maps and further on to evaluate the consequences of remaining errors and artifacts for the interpretation of physical quantities inferred through atmospheric model inversions.

  8. Majorization-minimization algorithms for wavelet-based image restoration.

    Science.gov (United States)

    Figueiredo, Mário A T; Bioucas-Dias, José M; Nowak, Robert D

    2007-12-01

    Standard formulations of image/signal deconvolution under wavelet-based priors/regularizers lead to very high-dimensional optimization problems involving the following difficulties: the non-Gaussian (heavy-tailed) wavelet priors lead to objective functions which are nonquadratic, usually nondifferentiable, and sometimes even nonconvex; the presence of the convolution operator destroys the separability which underlies the simplicity of wavelet-based denoising. This paper presents a unified view of several recently proposed algorithms for handling this class of optimization problems, placing them in a common majorization-minimization (MM) framework. One of the classes of algorithms considered (when using quadratic bounds on nondifferentiable log-priors) shares the infamous "singularity issue" (SI) of "iteratively reweighted least squares" (IRLS) algorithms: the possibility of having to handle infinite weights, which may cause both numerical and convergence issues. In this paper, we prove several new results which strongly support the claim that the SI does not compromise the usefulness of this class of algorithms. Exploiting the unified MM perspective, we introduce a new algorithm, resulting from using l1 bounds for nonconvex regularizers; the experiments confirm the superior performance of this method, when compared to the one based on quadratic majorization. Finally, an experimental comparison of the several algorithms, reveals their relative merits for different standard types of scenarios.

  9. Restoration of solar and star images with phase diversity-based blind deconvolution

    Institute of Scientific and Technical Information of China (English)

    Qiang Li; Sheng Liao; Honggang Wei; Mangzuo Shen

    2007-01-01

    The images recorded by a ground-based telescope are often degraded by atmospheric turbulence and the aberration of the optical system. Phase diversity-based blind deconvolution is an effective post-processing method that can be used to overcome the turbulence-induced degradation. The method uses an ensemble of short-exposure images obtained imultaneously from multiple cameras to jointly estimate the object and the wavefront distribution on pupil. Based on signal estimation theory and optimization theory, we derive the cost function and solve the large-scale optimization problem using a limited memory Broyden-Fletcher-Goldfarb-Shanno (L-BFGS) method. We apply the method to the urbulence degraded images generated with computer, the solar images acquired with the swedish vacuum solar telescope (SVST, 0.475m) in La Paima and the star images collected with 1.2-m telescope in Yunnan Observatory. In order to avoid edge effect in the restoration of the solar images, a modified Hanning apodized window is adopted.The star image till can be estored when the defocus distance is measured inaccurately. The restored results demonstrate that the method is efficient for removing the effect of turbulence and reconstructing the point-like or extended objects.

  10. Accuracy assessment of blind and semi-blind restoration methods for hyperspectral images

    Science.gov (United States)

    Zhang, Mo; Vozel, Benoit; Chehdi, Kacem; Uss, Mykhail; Abramov, Sergey; Lukin, Vladimir

    2016-10-01

    Hyperspectral images acquired by remote sensing systems are generally degraded by noise and can be sometimes more severely degraded by blur. When no knowledge is available about the degradations present or the original image, blind restoration methods must be considered. Otherwise, when a partial information is needed, semi-blind restoration methods can be considered. Numerous semi-blind and quite advanced methods are available in the literature. So to get better insights and feedback on the applicability and potential efficiency of a representative set of four semi-blind methods recently proposed, we have performed a comparative study of these methods in objective terms of blur filter and original image error estimation accuracy. In particular, we have paid special attention to the accurate recovering in the spectral dimension of original spectral signatures. We have analyzed peculiarities and factors restricting the applicability of these methods. Our tests are performed on a synthetic hyperspectral image, degraded with various synthetic blurs (out-of-focus, gaussian, motion) and with signal independent noise of typical levels such as those encountered in real hyperspectral images. This synthetic image has been built from various samples from classified areas of a real-life hyperspectral image, in order to benefit from realistic reference spectral signatures to recover after synthetic degradation. Conclusions, practical recommendations and perspectives are drawn from the results experimentally obtained.

  11. Simultaneous Tumor Segmentation, Image Restoration, and Blur Kernel Estimation in PET Using Multiple Regularizations.

    Science.gov (United States)

    Li, Laquan; Wang, Jian; Lu, Wei; Tan, Shan

    2017-02-01

    Accurate tumor segmentation from PET images is crucial in many radiation oncology applications. Among others, partial volume effect (PVE) is recognized as one of the most important factors degrading imaging quality and segmentation accuracy in PET. Taking into account that image restoration and tumor segmentation are tightly coupled and can promote each other, we proposed a variational method to solve both problems simultaneously in this study. The proposed method integrated total variation (TV) semi-blind de-convolution and Mumford-Shah segmentation with multiple regularizations. Unlike many existing energy minimization methods using either TV or L2 regularization, the proposed method employed TV regularization over tumor edges to preserve edge information, and L2 regularization inside tumor regions to preserve the smooth change of the metabolic uptake in a PET image. The blur kernel was modeled as anisotropic Gaussian to address the resolution difference in transverse and axial directions commonly seen in a clinic PET scanner. The energy functional was rephrased using the Γ-convergence approximation and was iteratively optimized using the alternating minimization (AM) algorithm. The performance of the proposed method was validated on a physical phantom and two clinic datasets with non-Hodgkin's lymphoma and esophageal cancer, respectively. Experimental results demonstrated that the proposed method had high performance for simultaneous image restoration, tumor segmentation and scanner blur kernel estimation. Particularly, the recovery coefficients (RC) of the restored images of the proposed method in the phantom study were close to 1, indicating an efficient recovery of the original blurred images; for segmentation the proposed method achieved average dice similarity indexes (DSIs) of 0.79 and 0.80 for two clinic datasets, respectively; and the relative errors of the estimated blur kernel widths were less than 19% in the transversal direction and 7% in the axial

  12. Restoration of distorted colour microscopic images from transverse chromatic aberration of imperfect lenses.

    Science.gov (United States)

    Wu, H-S; Murray, J; Morgello, S; Fiel, M I; Schiano, T; Kalir, T; Deligdisch, L; Gil, J

    2011-02-01

    An algorithm is presented for restoration of colour microscopic images with distortions from imperfect microscope lenses having transverse chromatic aberrations, resulting in a magnification that slightly varies with wavelengths or colours. The differential of each colour component image is computed as the difference between the component image and its slightly magnified version. The absolute values in the differential component images are generally higher at the edges where greater discontinuities occur. The two cross-correlation functions of the absolute differentials between red and green colours and between red and blue colours are then computed. The maximum in the two cross-correlation functions were sought, respectively, and the cross-correlation delays were then calculated. The two cross-correlation delays were used to determine dispersions and to realign the three colour components. Results of real microscopic images are provided. The restored image and the original are compared both visually and quantitatively in terms of the estimated entropies measured for the degree of concentrations using vector distributions.

  13. Image restoration with surface-based fourth-order partial differential equation

    Science.gov (United States)

    Lu, Bibo; Liu, Qiang

    2010-07-01

    This paper presents an edge-preserving fourth order partial differential equation (PDE) for image restoration derived from a new surface-based energy functional. The corresponding fourth order PDE can preserve edges and avoid the staircase effect. The proposed model contains a function of gradient norm as an edge detector, which controls the diffusion speed according to the local structure of the image and preserves more details. Denoising results are given and we have also compared our method with some related PDE models.

  14. The Analytic Hierarchy Method-Based Algorithm for Restoring Broken Pixels on the Noisy Images

    Directory of Open Access Journals (Sweden)

    S. V. Belim

    2014-01-01

    Full Text Available This article presents an algorithm for restoring broken pixels, which can appear in graphic files with statistical gaps. The suggested algorithm is based on the method of hierarchical analysis of the decision support theory. The choice of the broken pixel color depends on the nearest neighbors and their next neighbors. Three parameters inherent in each nearest neighbor are analysed. Firstly, it is the number of neighbors, which have the same color as the given nearest neighbor. Secondly, it is a deviation of the given pixel from the average value of its neighbors. Thirdly, it is a difference between the pixels being on the opposite sides of the broken pixel. Based on these three criteria, for each nearest neighbor of the broken pixel, a weight coefficient is defined. A hierarchical two-level tree for making decision is constructed. As a color of the broken pixel, its neighbor color with the maximum weight is chosen.A computer experiment to determine the effectiveness of the proposed method is conducted. The effectiveness of the proposed method was determined by comparing the similarity degree of the broken and restored images to the source image. To compare images Minkowski metric was used. To conduct experiments photographic and artificial images were used. The paper investigates a dependence of the proposed algorithm efficiency on the broken image amount. It was found out that the proposed algorithm has the advantage over the known algorithms for restoring broken pixels near the sharp edges. An image restored by our method has more sharply defined edges as compared to what the smoothing filters provide. The proposed method can be iteratively applied. As the experiments have shown, the first five iterations provide image enhancement.The proposed method together with the algorithms for detecting the broken pixels can be used to design filters of noisy images. The method efficiency enhancement can be achieved in case of taking into account the

  15. Nonlocal image restoration with bilateral variance estimation: a low-rank approach.

    Science.gov (United States)

    Dong, Weisheng; Shi, Guangming; Li, Xin

    2013-02-01

    Simultaneous sparse coding (SSC) or nonlocal image representation has shown great potential in various low-level vision tasks, leading to several state-of-the-art image restoration techniques, including BM3D and LSSC. However, it still lacks a physically plausible explanation about why SSC is a better model than conventional sparse coding for the class of natural images. Meanwhile, the problem of sparsity optimization, especially when tangled with dictionary learning, is computationally difficult to solve. In this paper, we take a low-rank approach toward SSC and provide a conceptually simple interpretation from a bilateral variance estimation perspective, namely that singular-value decomposition of similar packed patches can be viewed as pooling both local and nonlocal information for estimating signal variances. Such perspective inspires us to develop a new class of image restoration algorithms called spatially adaptive iterative singular-value thresholding (SAIST). For noise data, SAIST generalizes the celebrated BayesShrink from local to nonlocal models; for incomplete data, SAIST extends previous deterministic annealing-based solution to sparsity optimization through incorporating the idea of dictionary learning. In addition to conceptual simplicity and computational efficiency, SAIST has achieved highly competent (often better) objective performance compared to several state-of-the-art methods in image denoising and completion experiments. Our subjective quality results compare favorably with those obtained by existing techniques, especially at high noise levels and with a large amount of missing data.

  16. Wide-area image restoration using a new iterative registration method

    Science.gov (United States)

    Fraser, Donald; Lambert, Andrew J.

    2000-11-01

    Over a wide field of view (e.g., 100 arcsec in optical astronomy) the point spread function due to atmospheric effects is found to be far form position invariant, and appears as a combination of local warping and local blurring. Recently, we discussed a method in which the first step in restoration is to register all points in every frame of a movie sequence to the corresponding points in a prototype image. After registration, each frame is de- warped and summed to form an average, motion-blur corrected result. Previously, we applied a hierarchical, windowed cross correlation process to obtain local x and y registration information, similar to common methods in stereo cartography. We discuss a new approach to image registration for this purpose. Suppose two images to be registered differ mainly in varying random, but spatially coherent warping (such as occurs as one effect of a slowly varying wavefront tip-tilt over a wide field of vies). Imagine that one image, the reference image, is represented by a solid surface corresponding to its intensity distribution. Imagine that the second image is also represented by a surface, but in the form of a flexible, rubber mold. If the two images are identical, then the mold fits the solid like a glove. If one image includes local warping relative to the other, then the mold or glove must be forced to fit though local distortions.

  17. Optimal selection of regularization parameter for l1-based image restoration based on SURE

    Science.gov (United States)

    Xue, Feng; Liu, Xin; Liu, Hongyan; Liu, Jiaqi

    2016-10-01

    To exploit the sparsity in transform domain (e.g. wavelets), the image deconvolution can be typically formulated as a l1-penalized minimization problem, which, however, generally requires proper selection of regularization parameter for desired reconstruction quality. The key contribution of this paper is to develop a novel data-driven scheme to optimize regularization parameter, such that the resultant restored image achieves minimum prediction error (p-error). First, we develop Stein's unbiased risk estimate (SURE), an unbiased estimate of p-error, for image degradation model. Then, we propose a recursive evaluation of SURE for the basic iterative shrinkage/thresholding (IST), which enables us to find the optimal value of regularization parameter by exhaustive search. The numerical experiments show that the proposed SURE-based optimization leads to nearly optimal deconvolution performance in terms of peak signal-to-noise ratio (PSNR).

  18. Missing pixels restoration for remote sensing images using adaptive search window and linear regression

    Science.gov (United States)

    Tai, Shen-Chuan; Chen, Peng-Yu; Chao, Chian-Yen

    2016-07-01

    The Consultative Committee for Space Data Systems proposed an efficient image compression standard that can do lossless compression (CCSDS-ICS). CCSDS-ICS is the most widely utilized standard for satellite communications. However, the original CCSDS-ICS is weak in terms of error resilience with even a single incorrect bit possibly causing numerous missing pixels. A restoration algorithm based on the neighborhood similar pixel interpolator is proposed to fill in missing pixels. The linear regression model is used to generate the reference image from other panchromatic or multispectral images. Furthermore, an adaptive search window is utilized to sieve out similar pixels from the pixels in the search region defined in the neighborhood similar pixel interpolator. The experimental results show that the proposed methods are capable of reconstructing missing regions with good visual quality.

  19. Solving Quasi-Variational Inequalities for Image Restoration with Adaptive Constraint Sets

    KAUST Repository

    Lenzen, F.

    2014-01-01

    © 2014 Society for Industrial and Applied Mathematics. We consider a class of quasi-variational inequalities (QVIs) for adaptive image restoration, where the adaptivity is described via solution-dependent constraint sets. In previous work we studied both theoretical and numerical issues. While we were able to show the existence of solutions for a relatively broad class of problems, we encountered difficulties concerning uniqueness of the solution as well as convergence of existing algorithms for solving QVIs. In particular, it seemed that with increasing image size the growing condition number of the involved differential operator posed severe problems. In the present paper we prove uniqueness for a larger class of problems, particularly independent of the image size. Moreover, we provide a numerical algorithm with proved convergence. Experimental results support our theoretical findings.

  20. Metal Artifact Reduction from Computed Tomography (CT Images using Directional Restoration Filter

    Directory of Open Access Journals (Sweden)

    Mithun Kumar PK

    2014-05-01

    Full Text Available Computed tomography angiography (CTA is a stabilized tool for vessel imaging in the medical image processing field. High-intense structures in the contrast image can seriously hamper luminal visualization. Metal artifacts are an extensive problem in computed tomography (CT images. We proposed directional restoration filtering process with Fuzzy logic in order to reduce metal artifact from CT images. We create two sets by iteration process and these sets will be sorted in ascending order. After sorting we take two elements from two data sets and the tracking both elements will be selected from the second position of those sorting arrays. Intersection Fuzzy logic will be executed between two selected elements and Gaussian convolution operation will be performed in the entire images because of enhancement the artifact affected CT images. In this paper, we investigated a fully automated intensity-based filter and it depends on the gray level variation rating. This results in a better visualization of the vessel lumen, also of the smaller vessels, allowing a faster and more accurate inspection of the whole vascular structures.

  1. Optical coherence tomography based imaging of dental demineralisation and cavity restoration in 840 nm and 1310 nm wavelength regions

    Science.gov (United States)

    Damodaran, Vani; Rao, Suresh Ranga; Vasa, Nilesh J.

    2016-08-01

    In this paper, a study of in-house built optical coherence tomography (OCT) system with a wavelength of 840 nm for imaging of dental caries, progress in demineralisation and cavity restoration is presented. The caries when imaged with the 840 nm OCT system showed minute demineralisation in the order of 5 μm. The OCT system was also proposed to study the growth of lesion and this was demonstrated by artificially inducing caries with a demineralisation solution of pH 4.8. The progress of carious lesion to a depth of about 50-60 μm after 60 hours of demineralisation was clearly observed with the 840 nm OCT system. The tooth samples were subjected to accelerated demineralisation condition at pH of approximately 2.3 to study the adverse effects and the onset of cavity formation was clearly observed. The restoration of cavity was also studied by employing different restorative materials (filled and unfilled). In the case of restoration without filler material (unfilled), the restoration boundaries were clearly observed. Overall, results were comparable with that of the widely used 1310 nm OCT system. In the case of restoration with filler material, the 1310 nm OCT imaging displayed better imaging capacity due to lower scattering than 840 nm imaging.

  2. Determining Optimal Fluorescent Agent Concentrations in Dental Adhesive Resins for Imaging the Tooth/Restoration Interface.

    Science.gov (United States)

    Bim Júnior, Odair; Cebim, Marco A; Atta, Maria T; Machado, Camila M; Francisconi-Dos-Rios, Luciana F; Wang, Linda

    2017-02-01

    Fluorescent dyes like Rhodamine B (RB) have been used to identify the spatial distribution of adhesive restorative materials in the tooth/restoration interface. Potential effects of the addition of RB to dental adhesives were addressed in the past, but no further information is available on how to determine suitable concentrations of RB in these bonding agents for imaging in the confocal laser scanning microscope. This study provides systematical strategies for adding RB to viscous dental adhesive resins, focusing on the determination of the lowest range of dye concentrations necessary to achieve an acceptable image of the dentin/adhesive interface. It was demonstrated that optimized images of the resin distribution in dentin can be produced with 0.1-0.02 mg/mL of RB in the (tested) adhesives. Our approaches took into account aspects related to the dye concentration, photophysical parameters in different host media, specimen composition and morphology to develop a rational use of the fluorescent agent with the resin-based materials. Information gained from this work can help optimize labeling methods using dispersions of low-molecular-weight dyes in different monomer blend systems.

  3. The optical synthetic aperture image restoration based on the improved maximum-likelihood algorithm

    Science.gov (United States)

    Geng, Zexun; Xu, Qing; Zhang, Baoming; Gong, Zhihui

    2012-09-01

    Optical synthetic aperture imaging (OSAI) can be envisaged in the future for improving the image resolution from high altitude orbits. Several future projects are based on optical synthetic aperture for science or earth observation. Comparing with equivalent monolithic telescopes, however, the partly filled aperture of OSAI induces the attenuation of the modulation transfer function of the system. Consequently, images acquired by OSAI instrument have to be post-processed to restore ones equivalent in resolution to that of a single filled aperture. The maximum-likelihood (ML) algorithm proposed by Benvenuto performed better than traditional Wiener filter did, but it didn't work stably and the point spread function (PSF), was assumed to be known and unchanged in iterative restoration. In fact, the PSF is unknown in most cases, and its estimation was expected to be updated alternatively in optimization. Facing these limitations of this method, an improved ML (IML) reconstruction algorithm was proposed in this paper, which incorporated PSF estimation by means of parameter identification into ML, and updated the PSF successively during iteration. Accordingly, the IML algorithm converged stably and reached better results. Experiment results showed that the proposed algorithm performed much better than ML did in peak signal to noise ratio, mean square error and the average contrast evaluation indexes.

  4. Rigorous mathematical investigation of a nonlinear anisotropic diffusion-based image restoration model

    Directory of Open Access Journals (Sweden)

    Tudor Barbu

    2014-06-01

    Full Text Available A nonlinear diffusion based image denoising technique is introduced in this paper. The proposed PDE denoising and restoration scheme is based on a novel diffusivity function that uses an automatically detected conductance parameter. A robust mathematical treatment is also provided for our anisotropic diffusion model. We demonstrate that edge-stopping function model is properly chosen, explaining the mathematical reasons behind it. Also, we perform a rigorous mathematical investigation on of the existence and uniqueness of the solution of our nonlinear diffusion equation. This PDE-based noise removal approach outperforms most diffusion-based methods, producing considerably better smoothing results and providing a much better edge preservation.

  5. Convex half-quadratic criteria and interacting auxiliary variables for image restoration.

    Science.gov (United States)

    Idier, J

    2001-01-01

    This paper deals with convex half-quadratic criteria and associated minimization algorithms for the purpose of image restoration. It brings a number of original elements within a unified mathematical presentation based on convex duality. Firstly, the Geman and Yang's and Geman and Reynolds's constructions are revisited, with a view to establishing the convexity properties of the resulting half-quadratic augmented criteria, when the original nonquadratic criterion is already convex. Secondly, a family of convex Gibbsian energies that incorporate interacting auxiliary variables is revealed as a potentially fruitful extension of the Geman and Reynolds's construction.

  6. Restoration and enhancement of textural properties in SAR images using second-order statistics

    Science.gov (United States)

    Nezry, Edmond; Kohl, Hans-Guenther; De Groof, Hugo

    1994-12-01

    Local second order properties, describing spatial relations between pixels are introduced into the single-point speckle adaptive filtering processes, in order to account for the effects of speckle spatial correlation and to enhance scene textural properties in the restored image. To this end, texture measures originating, first from local grey level co-occurrence matrices (GLCM), and second from the local autocorrelation functions (ACF) are used. Results obtained on 3-look processed ERS-1 FDC and PRI spaceborne images illustrate the performance allowed by the introduction of these texture measures in the structure retaining speckle adaptive filters. The observable texture in remote sensing images is related to the physical spatial resolution of the sensor. For this reason, other spatial speckle decorrelation methods, more simple and easier to implement, for example post-filtering and linear image resampling, are also presented in this paper. In the particular case of spaceborne SAR imagery, all these methods lead to visually similar results. They produce filtered (radar reflectivity) images visually comparable to optical images.

  7. Semi-Huber Quadratic Function and Comparative Study of Some MRFs for Bayesian Image Restoration

    Science.gov (United States)

    De la Rosa, J. I.; Villa-Hernández, J.; González-Ramírez, E.; De la Rosa, M. E.; Gutiérrez, O.; Olvera-Olvera, C.; Castañeda-Miranda, R.; Fleury, G.

    2013-10-01

    The present work introduces an alternative method to deal with digital image restoration into a Bayesian framework, particularly, the use of a new half-quadratic function is proposed which performance is satisfactory compared with respect to some other functions in existing literature. The bayesian methodology is based on the prior knowledge of some information that allows an efficient modelling of the image acquisition process. The edge preservation of objects into the image while smoothing noise is necessary in an adequate model. Thus, we use a convexity criteria given by a semi-Huber function to obtain adequate weighting of the cost functions (half-quadratic) to be minimized. The principal objective when using Bayesian methods based on the Markov Random Fields (MRF) in the context of image processing is to eliminate those effects caused by the excessive smoothness on the reconstruction process of image which are rich in contours or edges. A comparison between the new introduced scheme and other three existing schemes, for the cases of noise filtering and image deblurring, is presented. This collection of implemented methods is inspired of course on the use of MRFs such as the semi-Huber, the generalized Gaussian, the Welch, and Tukey potential functions with granularity control. The obtained results showed a satisfactory performance and the effectiveness of the proposed estimator with respect to other three estimators.

  8. DEVELOPMENT OF OPTIMAL FILTERS OBTAINED THROUGH CONVOLUTION METHODS, USED FOR FINGERPRINT IMAGE ENHANCEMENT AND RESTORATION

    Directory of Open Access Journals (Sweden)

    Cătălin LUPU

    2014-12-01

    Full Text Available This article presents the development of optimal filters through covolution methods, necessary for restoring, correcting and improving fingerprints acquired from a sensor, able to provide the most ideal image in the output. After the image was binarized and equalized, Canny filter is applied in order to: eliminate the noise (filtering the image with a Gaussian filter, non-maxima suppression, module gradient adaptive binarization and extension edge points edges by hysteresis. The resulting image after applying Canny filter is not ideal. It is possible that the result will be an image with very fragmented edges and many pores in ridge. For the resulting image, a bank of convolution filters are applied one after another (Kirsch, Laplace, Roberts, Prewitt, Sobel, Frei-Chen, averaging convolution filter, circular convolution filter, lapacian convolution filter, gaussian convolution filter, LoG convolution filter, DoG, inverted filters, Wiener, the filter of ”equalization of the power spectrum” (intermediary filter between the Wiener filter and the inverted filter, the geometrical average filter , etc. with different features.

  9. Mammography image restoration based on a radiographic scattering model from a single projection: Experimental study

    Science.gov (United States)

    Kim, Kyuseok; Park, Soyoung; Kim, Guna; Cho, Hyosung; Je, Uikyu; Park, Chulkyu; Lim, Hyunwoo; Lee, Dongyeon; Lee, Hunwoo; Kang, Seokyoon

    2017-03-01

    In conventional mammography, contrast sensitivity remains limited due to the superimposition of breast tissue and scattered X-rays, which induces low visibility of lesions in the breast and, thus, an excessive number of false-positive findings. Several methods, including digital breast tomosynthesis as a multiplanar imaging modality, air-gap and slot techniques for the reduction of scatters, phase-contrast imaging as another image-contrast modality, etc., have been investigated in attempt to overcome these difficulties. However, those techniques typically require a higher imaging dose or special equipment. In this work, as an alternative, we propose a new image restoration method based on a radiographic scattering model in which the intensity of scattered X-rays and the direct transmission function of a given medium are estimated from a single projection by using the dark-channel prior. We implemented the proposed algorithm and performed an experiment to demonstrate its viability. Our results indicate that most of the structures in the examined breast were very discernable even with no adjustment in the display-window level, thus preserving superior image features and edge sharpening.

  10. Adaptive Subspace-based Inverse Projections via Division into Multiple Sub-problems for Missing Image Data Restoration.

    Science.gov (United States)

    Ogawa, Takahiro; Haseyama, Miki

    2016-10-10

    This paper presents adaptive subspace-based inverse projections via division into multiple sub-problems (ASIP-DIMS) for missing image data restoration. In the proposed method, a target problem for estimating missing image data is divided into multiple sub-problems, and each sub-problem is iteratively solved with constraints of other known image data. By projection into a subspace model of image patches, the solution of each subproblem is calculated, where we call this procedure "subspacebased inverse projection" for simplicity. The proposed method can use higher-dimensional subspaces for finding unique solutions in each sub-problem, and successful restoration becomes feasible since a high level of image representation performance can be preserved. This is the biggest contribution of this paper. Furthermore, the proposed method generates several subspaces from known training examples and enables derivation of a new criterion in the above framework to adaptively select the optimal subspace for each target patch. In this way, the proposed method realizes missing image data restoration using ASIP-DIMS. Since our method can estimate any kind of missing image data, its potential in two image restoration tasks, image inpainting and super-resolution, based on several methods for multivariate analysis is also shown in this paper.

  11. Evaluating the Effects of Shadow Detection on QuickBird Image Classification and Spectroradiometric Restoration

    Directory of Open Access Journals (Sweden)

    Marvin E. Bauer

    2013-09-01

    Full Text Available Shadows in high resolution imagery create significant problems for urban land cover classification and environmental application. We first investigated whether shadows were intrinsically different and hypothetically possible to separate from each other with ground spectral measurements. Both pixel-based and object-oriented methods were used to evaluate the effects of shadow detection on QuickBird image classification and spectroradiometric restoration. In each method, shadows were detected and separated either with or without histogram thresholding, and subsequently corrected with a k-nearest neighbor algorithm and a linear correlation correction. The results showed that shadows had distinct spectroradiometric characteristics, thus, could be detected with an optimal brightness threshold and further differentiated with a scene-based near infrared ratio. The pixel-based methods generally recognized more shadow areas and with statistically higher accuracy than the object-oriented methods. The effects of the prior shadow thresholding were not statistically significant. The accuracy of the final land cover classification, after accounting for the shadow detection and separation, was significantly higher for the pixel-based methods than for the object-oriented methods, although both achieved similar accuracy for the non-shadow classes. Both radiometric restoration algorithms significantly reduced shadow areas in the original satellite images.

  12. Multiscale Tikhonov-Total Variation Image Restoration Using Spatially Varying Edge Coherence Exponent.

    Science.gov (United States)

    Prasath, V B Surya; Vorotnikov, Dmitry; Pelapur, Rengarajan; Jose, Shani; Seetharaman, Guna; Palaniappan, Kannappan

    2015-12-01

    Edge preserving regularization using partial differential equation (PDE)-based methods although extensively studied and widely used for image restoration, still have limitations in adapting to local structures. We propose a spatially adaptive multiscale variable exponent-based anisotropic variational PDE method that overcomes current shortcomings, such as over smoothing and staircasing artifacts, while still retaining and enhancing edge structures across scale. Our innovative model automatically balances between Tikhonov and total variation (TV) regularization effects using scene content information by incorporating a spatially varying edge coherence exponent map constructed using the eigenvalues of the filtered structure tensor. The multiscale exponent model we develop leads to a novel restoration method that preserves edges better and provides selective denoising without generating artifacts for both additive and multiplicative noise models. Mathematical analysis of our proposed method in variable exponent space establishes the existence of a minimizer and its properties. The discretization method we use satisfies the maximum-minimum principle which guarantees that artificial edge regions are not created. Extensive experimental results using synthetic, and natural images indicate that the proposed multiscale Tikhonov-TV (MTTV) and dynamical MTTV methods perform better than many contemporary denoising algorithms in terms of several metrics, including signal-to-noise ratio improvement and structure preservation. Promising extensions to handle multiplicative noise models and multichannel imagery are also discussed.

  13. Underwater Image Processing: State of the Art of Restoration and Image Enhancement Methods

    Directory of Open Access Journals (Sweden)

    Silvia Corchs

    2010-01-01

    Full Text Available The underwater image processing area has received considerable attention within the last decades, showing important achievements. In this paper we review some of the most recent methods that have been specifically developed for the underwater environment. These techniques are capable of extending the range of underwater imaging, improving image contrast and resolution. After considering the basic physics of the light propagation in the water medium, we focus on the different algorithms available in the literature. The conditions for which each of them have been originally developed are highlighted as well as the quality assessment methods used to evaluate their performance.

  14. The use of amalgam powder and calcium hydroxide to recreate a radiopaque image of a lost dental restoration.

    Science.gov (United States)

    Shiroma, Calvin Y

    2002-05-01

    Radiographs of dental restorations are highly reliable when used to identify postmortem dental remains. A problem exists if key dental restorations are missing or defective, which results in the loss of a comparative radiographic image. This article describes a simple method allowing the odontologist to quickly recreate a temporary radiopaque restoration. This article presents a method of using amalgam powder (radiopaque material) and calcium hydroxide (radiopaque material and transport medium for the amalgam powder) to recreate a radiopaque image on a tooth that has lost a dental restoration. Amalgam powder and calcium hydroxide is easily obtained (in any dental office), fairly clean, easy to manipulate, inexpensive, inert, stable, and able to be removed without damaging the dental remains. The amalgam powder/calcium hydroxide mixture can easily be re-shaped or modified to reflect the radiopaque image of the original restoration. Radiographic comparison of the "restored" dental remains to the antemortem radiographs is now possible. The use of this technique is presented in a case report.

  15. State-space blur model for high-speed forward-moving imaging system and its recursive restoration

    Science.gov (United States)

    Cao, Fengmei; Chen, Xichun; Jin, Weiqi

    2007-01-01

    When an imaging system is approaching the object at a high speed, because of the existence of integration time, the images obtained are always blurred radially. Since the degradation process is space variant, this kind of blur is difficult to handle, traditional frequency domain techniques can't be applied here. Obviously, the radially blurred image obtained is rotation symmetrical, so the usual uniformly sampled image can be resampled with fan-shaped grids, and the gray level of these new sampling points build up a new image matrix. The new image matrix's columns and rows are never the edges of the image, but the image's radius and angle. So, the original two-dimensional problem is simplified. Even after the resampling, the blur is still space variant, and the PSF (point spread function) will change along the radius direction. So the authors come up with a state-space method, a state-space blur model is constructed, which handles the problem recursively. To restore the degraded image simply means to find the inverse of the degradation system and computer simulation result shows the restoration algorithm restored the radially blurred image approvingly.

  16. Introduction to the Restoration of Astrophysical Images by Multiscale Transforms and Bayesian Methods

    Science.gov (United States)

    Bijaoui, A.

    2013-03-01

    The image restoration is today an important part of the astrophysical data analysis. The denoising and the deblurring can be efficiently performed using multiscale transforms. The multiresolution analysis constitutes the fundamental pillar for these transforms. The discrete wavelet transform is introduced from the theory of the approximation by translated functions. The continuous wavelet transform carries out a generalization of multiscale representations from translated and dilated wavelets. The à trous algorithm furnishes its discrete redundant transform. The image denoising is first considered without any hypothesis on the signal distribution, on the basis of the a contrario detection. Different softening functions are introduced. The introduction of a regularization constraint may improve the results. The application of Bayesian methods leads to an automated adaptation of the softening function to the signal distribution. The MAP principle leads to the basis pursuit, a sparse decomposition on redundant dictionaries. Nevertheless the posterior expectation minimizes, scale per scale, the quadratic error. The proposed deconvolution algorithm is based on a coupling of the wavelet denoising with an iterative inversion algorithm. The different methods are illustrated by numerical experiments on a simulated image similar to images of the deep sky. A white Gaussian stationary noise was added with three levels. In the conclusion different important connected problems are tackled.

  17. AM Multipurpose High-Resolution Imaging Topological Radar (ITR): reverse engineering and artworks monitoring and restoration

    Science.gov (United States)

    Guarneri, Massimiliano; Bartolini, Luciano; Fornetti, Giorgio; Ferri De Collibus, Mario; De Dominicis, Luigi; Paglia, Emiliano; Poggi, Claudio; Ricci, Roberto

    2005-08-01

    A high resolution Amplitude Modulated Imaging Laser Radar (AM-LR) sensor has recently been developed, aimed to accurately reconstructing 3D digital models of real targets - either single objects or large amplitude complex scenes. The system sounding beam can be swept linearly across the object or circularly around it, by placing the object on a controlled rotating platform. Both intensity and phase shift of the back-scattered light are then collected and processed, providing respectively a shade-free photographic-like picture and accurate range data in the form of a range or depth image, with accuracy depending mainly on the laser modulation frequency. The development of software, suitable for simultaneous 3D rendering of the intensity and absolute distance data collected by the ITR, constitutes one of the main objectives of the research activity, whatever is the application pursued. In fact, high resolution AM-LR systems have a great interest for their potentials in accurate 3D imaging of valuable objects which must be preserved in digital archives. Examples range from artwork monitoring, cataloguing and restoration from sparse fragments, to medicine for non-hazardous diagnostics and fast design of bio-compatible prostheses, to microtechnology in the miniaturization of macro-components (plastic prototypes, quality control). Several meaningful results of measurements executed in various important European archaeological sites, in particular Santa Maria Antiqua church situated in Fori Imperiali area in Rome and Costanza (Romania), involving 3D color mapped representation are also presented.

  18. 2D Iterative MAP Detection: Principles and Applications in Image Restoration

    Directory of Open Access Journals (Sweden)

    D. Kekrt

    2014-06-01

    Full Text Available The paper provides a theoretical framework for the two-dimensional iterative maximum a posteriori detection. This generalization is based on the concept of detection algorithms BCJR and SOVA, i.e., the classical (one-dimensional iterative detectors used in telecommunication applications. We generalize the one-dimensional detection problem considering the spatial ISI kernel as a two-dimensional finite state machine (2D FSM representing a network of the spatially concatenated elements. The cellular structure topology defines the design of the 2D Iterative decoding network, where each cell is a general combination-marginalization statistical element (SISO module exchanging discrete probability density functions (information metrics with neighboring cells. In this paper, we statistically analyse the performance of various topologies with respect to their application in the field of image restoration. The iterative detection algorithm was applied on the task of binarization of images taken from a CCD camera. The reconstruction includes suppression of the defocus caused by the lens, CCD sensor noise suppression and interpolation (demosaicing. The simulations prove that the algorithm provides satisfactory results even in the case of an input image that is under-sampled due to the Bayer mask.

  19. Restoring Charlemagne’s chapel: historical consciousness, material culture, and transforming images of Aachen in the 1840s

    Directory of Open Access Journals (Sweden)

    Jenny H. Shaffer

    2012-12-01

    Full Text Available The 1840s offer crystallizing images of Charlemagne’s chapel at Aachen that continue to resonate. In this decade, the Carolingian building, restored in words and images by scholars, made an auspicious debut within the coalescing discipline of art history. Simultaneously, the well-known restoration of the extant medieval chapel, which began in the 1850s, found sure footing as the chapel’s columnar screen, which Napoleon had removed, was reinserted. While these co-existing, interrelated restoration movements – focused on the chapel’s dilapidated state and notions of its importance as an imperial, Christian, and German work – diverged in methods and results after mid-century, they remain central to understanding both the chapel in scholarship and the extraordinary monument in the town centre of Aachen today.

  20. Application of color image processing and low-coherent optical computer tomography in evaluation of adhesive interfaces of dental restorations

    Science.gov (United States)

    Bessudnova, Nadezda O.; Shlyapnikova, Olga A.; Venig, Sergey B.; Genina, Elina A.; Sadovnikov, Alexandr V.

    2015-03-01

    Durability of bonded interfaces between dentin and a polymer material in resin-based composite restorations remains a clinical dentistry challenge. In the present study the evolution of bonded interfaces in biological active environment is estimated in vivo. A novel in vivo method of visual diagnostics that involves digital processing of color images of composite restorations and allows the evaluation of adhesive interface quality over time, has been developed and tested on a group of volunteers. However, the application of the method is limited to the analysis of superficial adhesive interfaces. Low-coherent optical computer tomography (OCT) has been tested as a powerful non-invasive tool for in vivo, in situ clinical diagnostics of adhesive interfaces over time. In the long-term perspective adhesive interface monitoring using standard methods of clinical diagnostics along with colour image analysis and OCT could make it possible to objectivise and prognosticate the clinical longevity of composite resin-based restorations with adhesive interfaces.

  1. Region-confined restoration method for motion-blurred star image of the star sensor under dynamic conditions.

    Science.gov (United States)

    Ma, Liheng; Bernelli-Zazzera, Franco; Jiang, Guangwen; Wang, Xingshu; Huang, Zongsheng; Qin, Shiqiao

    2016-06-10

    Under dynamic conditions, the centroiding accuracy of the motion-blurred star image decreases and the number of identified stars reduces, which leads to the degradation of the attitude accuracy of the star sensor. To improve the attitude accuracy, a region-confined restoration method, which concentrates on the noise removal and signal to noise ratio (SNR) improvement of the motion-blurred star images, is proposed for the star sensor under dynamic conditions. A multi-seed-region growing technique with the kinematic recursive model for star image motion is given to find the star image regions and to remove the noise. Subsequently, a restoration strategy is employed in the extracted regions, taking the time consumption and SNR improvement into consideration simultaneously. Simulation results indicate that the region-confined restoration method is effective in removing noise and improving the centroiding accuracy. The identification rate and the average number of identified stars in the experiments verify the advantages of the region-confined restoration method.

  2. A neural learning approach for adaptive image restoration using a fuzzy model-based network architecture.

    Science.gov (United States)

    Wong, H S; Guan, L

    2001-01-01

    We address the problem of adaptive regularization in image restoration by adopting a neural-network learning approach. Instead of explicitly specifying the local regularization parameter values, they are regarded as network weights which are then modified through the supply of appropriate training examples. The desired response of the network is in the form of a gray level value estimate of the current pixel using weighted order statistic (WOS) filter. However, instead of replacing the previous value with this estimate, this is used to modify the network weights, or equivalently, the regularization parameters such that the restored gray level value produced by the network is closer to this desired response. In this way, the single WOS estimation scheme can allow appropriate parameter values to emerge under different noise conditions, rather than requiring their explicit selection in each occasion. In addition, we also consider the separate regularization of edges and textures due to their different noise masking capabilities. This in turn requires discriminating between these two feature types. Due to the inability of conventional local variance measures to distinguish these two high variance features, we propose the new edge-texture characterization (ETC) measure which performs this discrimination based on a scalar value only. This is then incorporated into a fuzzified form of the previous neural network which determines the degree of membership of each high variance pixel in two fuzzy sets, the EDGE and TEXTURE fuzzy sets, from the local ETC value, and then evaluates the appropriate regularization parameter by appropriately combining these two membership function values.

  3. New layer-based imaging and rapid prototyping techniques for computer-aided design and manufacture of custom dental restoration.

    Science.gov (United States)

    Lee, M-Y; Chang, C-C; Ku, Y C

    2008-01-01

    Fixed dental restoration by conventional methods greatly relies on the skill and experience of the dental technician. The quality and accuracy of the final product depends mostly on the technician's subjective judgment. In addition, the traditional manual operation involves many complex procedures, and is a time-consuming and labour-intensive job. Most importantly, no quantitative design and manufacturing information is preserved for future retrieval. In this paper, a new device for scanning the dental profile and reconstructing 3D digital information of a dental model based on a layer-based imaging technique, called abrasive computer tomography (ACT) was designed in-house and proposed for the design of custom dental restoration. The fixed partial dental restoration was then produced by rapid prototyping (RP) and computer numerical control (CNC) machining methods based on the ACT scanned digital information. A force feedback sculptor (FreeForm system, Sensible Technologies, Inc., Cambridge MA, USA), which comprises 3D Touch technology, was applied to modify the morphology and design of the fixed dental restoration. In addition, a comparison of conventional manual operation and digital manufacture using both RP and CNC machining technologies for fixed dental restoration production is presented. Finally, a digital custom fixed restoration manufacturing protocol integrating proposed layer-based dental profile scanning, computer-aided design, 3D force feedback feature modification and advanced fixed restoration manufacturing techniques is illustrated. The proposed method provides solid evidence that computer-aided design and manufacturing technologies may become a new avenue for custom-made fixed restoration design, analysis, and production in the 21st century.

  4. 盲复原高斯模糊图像%The blind restoration of Gaussian blurred images

    Institute of Scientific and Technical Information of China (English)

    丁左红; 郭汉明; 高秀敏; 蓝景恒; 翁晓羽; 满忠胜; 庄松林

    2011-01-01

    经典的图像恢复算法设点扩展函数(PSF)是已知的,然而在许多情况下PSF难以确定,不得不在只知道成像系统部分信息甚至没有任何信息的情况下估计真实图像和PSF,这一过程称为图像盲复原.对于高斯模糊图像,它的PSF是很难被检测出来的,因此高斯模糊图像的盲复原一直是个棘手的问题.利用高斯点扩展函数的特性,初始估计PSF并对加噪后的模糊图像进行维纳滤波,后经过中值滤波获得恢复图像.恢复的图像主观视觉效果较好,具有良好的抗噪性,复原效果明显.该方法对于提高图像质量有一定的参考价值.%Classical image restoration algorithm is based on point spread function (PSF) is known. However, it is difficult to determine PSF in many cases, we have to estimate the true image and PSF in the case of only knowing some of the information or no information of imaging systems, this process is called blind image restoration. For the Gaussian blurred image, it is very difficult to detect PSF, so blind restoration of the Gaussian blurred image has been a troublesome issue. In this paper, we suppose the initial PSF using the characteristics of Gaussian PSF, and do Wiener filtering based on Gaussian blurred image with noise, then gain the restoration image through the median filtering. Experiment shows that, restored image is better in subjective visual effect, and remarkable in recovery effect with good noise immunity. This method has some reference value to improve the image quality.

  5. Liquid crystal TV-based white light optical tracking novelty filter.

    Science.gov (United States)

    Li, Y; Kostrzewski, A; Kim, D H; Eichmann, G

    1989-11-15

    A compact white light optical tracking novelty filter is demonstrated. Based on the use of two inexpensive liquid crystal televisions, a filtered and collimated white light source, digital delay, and video recorder, this portable white light device performs two major image comparison operations, a real time image subtraction and novelty tracking operations. Some preliminary experimental results are presented.

  6. Radiopacity of restorative materials using digital images Radiopacidade de materiais restauradores utilizando imagens digitais

    Directory of Open Access Journals (Sweden)

    Leda Maria Pescinini Salzedas

    2006-04-01

    Full Text Available The radiopacity of esthetic restorative materials has been established as an important requirement, improving the radiographic diagnosis. The aim of this study was to evaluate the radiopacity of six restorative materials using a direct digital image system, comparing them to the dental tissues (enamel-dentin, expressed as equivalent thickness of aluminum (millimeters of aluminum. Five specimens of each material were made. Three 2-mm thick longitudinal sections were cut from an intact extracted permanent molar tooth (including enamel and dentin. An aluminum step wedge with 9 steps was used. The samples of different materials were placed on a phosphor plate together with a tooth section, aluminum step wedge and metal code letter, and were exposed using a dental x-ray unit. Five measurements of radiographic density were obtained from each image of each item assessed (restorative material, enamel, dentin, each step of the aluminum step wedge and the mean of these values was calculated. Radiopacity values were subsequently calculated as equivalents of aluminum thickness. Analysis of variance (ANOVA indicated significant differences in radiopacity values among the materials (PA radiopacidade dos materiais tem sido valorizada como importante requisito, incrementando o diagnóstico radiográfico. O objetivo deste estudo foi avaliar, no sistema digital Digora, as densidades radiográficas de 06 materiais restauradores comparando-os aos tecidos dentais (esmalte e dentina, expressos em milímetros de alumínio (mm Al. Foram confeccionadas 05 amostras de cada material e três cortes de um molar extraído hígido (incluindo esmalte e dentina, com 2 mm de espessura, e um penetrômetro de alumínio com 09 degraus. Sobre cada placa óptica foram colocados amostras dos diferentes materiais, um corte do dente humano, o penetrômetro e a identificação, e feita a exposição utilizando um aparelho de raios X. Foram obtidas 05 medidas de densidade radiográfica de

  7. Application of image restoration and three-dimensional visualization techniques to frog microvessels in-situ loaded with fluorescent indicators

    Science.gov (United States)

    Pagakis, Stamatis N.; Curry, Fitz-Roy E.; Lenz, Joyce F.

    1993-07-01

    In situ experiments on microvessels require image sensors of wide dynamic range due to large variations of the intensity in the scene, and 3D visualization due to the thickness of the preparation. The images require restoration because of the inherent tissue movement, out-of- focus-light contamination, and blur. To resolve the above problems, we developed an imaging system for quantitative imaging based on a 12 bits/pixel cooled CCD camera and a PC based digital imaging system. We applied the optical sectioning technique with image restoration using a modified nearest neighbor algorithm and iterative constrained deconvolution on each of the 2D optical sections. For the 3D visualization of the data, a volume rendering software was used. The data provided 3D images of the distribution of fluorescent indicators in intact microvessels. Optical cross sections were also compared with cross sections of the same microvessels examined in the electron microscope after their luminal surfaces were labeled with a tracer which was both electron dense and fluorescent. This procedure enabled precise identification of the endothelial cells in the microvessel wall as the principal site of accumulation of the fluorescent calcium indicator, fura-2, during microperfusion experiments.

  8. Blind restoration for nonuniform aerial images using nonlocal Retinex model and shearlet-based higher-order regularization

    Science.gov (United States)

    Chen, Rui; Jia, Huizhu; Xie, Xiaodong; Gao, Wen

    2017-05-01

    Aerial images are often degraded by space-varying motion blurs and simultaneous uneven illumination. To recover a high-quality aerial image from its nonuniform version, we propose a patchwise restoration approach based on a key observation that the degree of blurring is inevitably affected by the illumination conditions. A nonlocal Retinex model is developed to accurately estimate the reflectance component from the degraded aerial image. Thereafter, the uneven illumination is corrected well. Then nonuniform coupled blurring in the enhanced reflectance image is alleviated and transformed toward uniform distribution, which will facilitate the subsequent deblurring. For constructing the multiscale sparsified regularization, the discrete shearlet transform is improved to better represent anisotropic image features in terms of directional sensitivity and selectivity. In addition, a new adaptive variant of total generalized variation is proposed to act as the structure-preserving regularizer. These complementary regularizers are elegantly integrated into an objective function. The final deblurred image with uniform illumination can be obtained by applying a fast alternating direction scheme to solve the derived function. The experimental results demonstrate that our algorithm can not only effectively remove both the space-varying illumination and motion blurs in aerial images, but also recover the abundant details of aerial scenes with top-level objective and subjective quality, and outperforms other state-of-the-art restoration methods.

  9. Fast wavelet packet transform-based algorithm for numerical solution of image restoration problems in a parallel environment

    Science.gov (United States)

    Carracciuolo, Luisa; D'Amore, Luisa; Murli, Almerico

    1998-10-01

    We explore the filtering properties of wavelets functions in order to develop accurate and efficient numerical algorithms for Image Restoration problems. We propose a parallel implementation for MIMD distributed memory environments. The key insight of our approach is the use of distributed versions of Level 3 Basic Linear Algebra Subprograms as computational building blocks and the use of Basic Linear Algebra Communication Subprograms as communication building blocks for advanced architecture computers. The use of these low-level mathematical software libraries guarantees the development of efficient, portable and scalable high-level algorithms and hides many details of the parallelism from the user's point of view. Numerical experiments on a simulated image restoration applications are shown. The parallel software has been tested on a 12 nodes IBM SP2 available at the Center for Research on Parallel Computing and Supercomputers in Naples, Italy).

  10. High-resolution laser radar for 3D imaging in artwork cataloging, reproduction, and restoration

    Science.gov (United States)

    Ricci, Roberto; Fantoni, Roberta; Ferri de Collibus, Mario; Fornetti, Giorgio G.; Guarneri, Massimiliano; Poggi, Claudio

    2003-10-01

    A high resolution Amplitude Modulated Laser Radar (AM-LR) sensor has recently been developed, aimed at accurately reconstructing 3D digital models of real targets, either single objects or complex scenes. The sensor sounding beam can be swept linearly across the object or circularly around it, by placing the object on a controlled rotating platform, enabling to obtain respectively linear and cylindrical range maps. Both amplitude and phase shift of the modulating wave of back-scattered light are collected and processed, providing respectively a shade-free, high resolution, photographic-like picture and accurate range data in the form of a range image. The resolution of range measurements depends mainly on the laser modulation frequency, provided that the power of the backscattered light reaching the detector is at least a few nW (current best performances are ~100 μm). The complete object surface can be reconstructed from the sampled points by using specifically developed software tools. The system has been successfully applied to scan different types of real surfaces (stone, wood, alloys, bones), with relevant applications in different fields, ranging from industrial machining to medical diagnostics, to vision in hostile environments. Examples of artwork reconstructed models (pottery, marble statues) are presented and the relevance of this technology for reverse engineering applied to cultural heritage conservation and restoration are discussed. Final 3D models can be passed to numeric control machines for rapid-prototyping, exported in standard formats for CAD/CAM purposes and made available on the Internet by adopting a virtual museum paradigm, thus possibly enabling specialists to perform remote inspections on high resolution digital reproductions of hardly accessible masterpieces.

  11. CUDA-based acceleration and BPN-assisted automation of bilateral filtering for brain MR image restoration.

    Science.gov (United States)

    Chang, Herng-Hua; Chang, Yu-Ning

    2017-04-01

    Bilateral filters have been substantially exploited in numerous magnetic resonance (MR) image restoration applications for decades. Due to the deficiency of theoretical basis on the filter parameter setting, empirical manipulation with fixed values and noise variance-related adjustments has generally been employed. The outcome of these strategies is usually sensitive to the variation of the brain structures and not all the three parameter values are optimal. This article is in an attempt to investigate the optimal setting of the bilateral filter, from which an accelerated and automated restoration framework is developed. To reduce the computational burden of the bilateral filter, parallel computing with the graphics processing unit (GPU) architecture is first introduced. The NVIDIA Tesla K40c GPU with the compute unified device architecture (CUDA) functionality is specifically utilized to emphasize thread usages and memory resources. To correlate the filter parameters with image characteristics for automation, optimal image texture features are subsequently acquired based on the sequential forward floating selection (SFFS) scheme. Subsequently, the selected features are introduced into the back propagation network (BPN) model for filter parameter estimation. Finally, the k-fold cross validation method is adopted to evaluate the accuracy of the proposed filter parameter prediction framework. A wide variety of T1-weighted brain MR images with various scenarios of noise levels and anatomic structures were utilized to train and validate this new parameter decision system with CUDA-based bilateral filtering. For a common brain MR image volume of 256 × 256 × 256 pixels, the speed-up gain reached 284. Six optimal texture features were acquired and associated with the BPN to establish a "high accuracy" parameter prediction system, which achieved a mean absolute percentage error (MAPE) of 5.6%. Automatic restoration results on 2460 brain MR images received an average

  12. A Modern Image Quality Measurement Method for Blind Image Restoration%基于变分的盲图像复原质量评价指标

    Institute of Scientific and Technical Information of China (English)

    成孝刚; 安明伟; 阮雅端; 陈启美

    2013-01-01

    盲图像复原过程中,图像质量评价至关重要.通过分析重构图像质量与其总变分值之间的关系,提出了用于图像复原的一种基于总变分(Total bounded variation,TBV)的图像质量评估方法,并构建关系模型,证明了原始清晰图像的总变分值在所有模糊图像中具有极大值,且在所有重构图像的变分值中具有极小值.通过分析,得出结论:当总变分取极值时,基于所提度量方法,可以获得更好的盲图像重构效果.最后,比较了原始清晰图像、模糊图像和重构图像之间的变分值,计算机仿真验证了该方法的有效性和准确性.%In the process of blind image restoration, image quality assessment is of paramount importance. In this paper, A novel image quality assessment method is presented by analyzing the relation between reconstructed image quality and its total bounded variation (TBV), on this basis, the relationship model is constructed, that is, the original clear image's TBV is maximum in all the blurring image, and it is minimal in all the reconstructed image. Further, based on the metric method proposed, the better blind image reconstruction effect is obtained when the TBV is extremal. Finally, the TBV of original clear image, blurred images and blind restored images are compared, the simulation results shows the validation and veracity of the method proposed.

  13. A Hybrid Method of medical Image Restoration with Gaussian and Impulsive Noise; Un Metodo Hibrido de Restauracion de Images Medidas con Ruido Gausino e Impulsivo

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez, M. G.; Vidal, V.; Verdu, G.; Mayo, P.; Rodenas, F.

    2011-07-01

    The noise removal techniques to restore noisy images is currently an important issue, for example, medical images obtained by X-ray computed tomography in noise due to the use of a small number of projections present noise of different types. In this paper we analyze and evaluate two techniques that separately each behaves efficiently for the removal of Gaussian and impulsive noise respectively, and combined to form a hybrid approach obtains very good performance with respect to quality in most different types of noise.

  14. Iterative Lavrentiev regularization for symmetric kernel-driven operator equations: with application to digital image restoration problems

    Institute of Scientific and Technical Information of China (English)

    WANG Yanfei; GU Xingfa; YU Tao; FAN Shufang

    2005-01-01

    The symmetric kernel-driven operator equations play an important role in mathematical physics, engineering, atmospheric image processing and remote sensing sciences. Such problems are usually ill-posed in the sense that even if a unique solution exists, the solution need not depend continuously on the input data. One common technique to overcome the difficulty is applying the Tikhonov regularization to the symmetric kernel operator equations, which is more generally called the Lavrentiev regularization.It has been shown that the iterative implementation of the Tikhonov regularization can improve the rate of convergence. Therefore in this paper, we study the iterative Lavrentiev regularization method in a similar way when applying it to symmetric kernel problems which appears frequently in applications, say digital image restoration problems. We first prove the convergence property, and then under the widely used Morozov discrepancy principle(MDP), we prove the regularity of the method. Numerical performance for digital image restoration is included to confirm the theory. It seems that the iterated Lavrentiev regularization with the MDP strategy is appropriate for solving symmetric kernel problems.

  15. Reorganization characteristics of speech cortex during speech restoration following total laryngectomy A functional magnetic resonance imaging follow-up

    Institute of Scientific and Technical Information of China (English)

    Jianzhong Yin; Yonggang Xue; Peng Lin; Xuchu Weng; Ji Qi

    2011-01-01

    During speech restoration following laryngectomy, language-related cortical areas develop connections with new primary motor neurons. The present study followed up 18 patients after total resection of laryngeal carcinoma. According to an evaluation of pronunciation, patients were assigned to three groups: poor, moderate and good pronunciation. Functional magnetic resonance imaging revealed significant increases in the number of activated voxels and the intensity of activation changes in the left middle frontal gyrus, left precentral gyrus, left postcentral gyrus, left supplementary motor area, left anterior cingulate gyrus and right fusiform gyrus between the moderate pronunciation group compared with the poor and good pronunciation groups. We propose that these brain regions play an important role in the progress of speech restoration, and improvements in pronunciation learning for patients following laryngectomy. However, during the later period of speech restoration, the number of activated voxels and intensity changes in these regions decreased to the level of healthy controls, indicating that the learning and instruction effects weakened once patients had mastered pronunciation techniques.

  16. Satellite Image-based Estimates of Snow Water Equivalence in Restored Ponderosa Pine Forests in Northern Arizona

    Science.gov (United States)

    Sankey, T.; Springer, A. E.; O'Donnell, F. C.; Donald, J.; McVay, J.; Masek Lopez, S.

    2014-12-01

    The U.S. Forest Service plans to conduct forest restoration treatments through the Four Forest Restoration Initiative (4FRI) on hundreds of thousands of acres of ponderosa pine forest in northern Arizona over the next 20 years with the goals of reducing wildfire hazard and improving forest health. The 4FRI's key objective is to thin and burn the forests to create within-stand openings that "promote snowpack accumulation and retention which benefit groundwater recharge and watershed processes at the fine (1 to 10 acres) scale". However, little is known about how these openings created by restoration treatments affect snow water equivalence (SWE) and soil moisture, which are key parts of the water balance that greatly influence water availability for healthy trees and for downstream water users in the Sonoran Desert. We have examined forest canopy cover by calculating a Normalized Difference Vegetation Index (NDVI), a key indicator of green vegetation cover, using Landsat satellite data. We have then compared NDVI between treatments at our study sites in northern Arizona and have found statistically significant differences in tree canopy cover between treatments. The control units have significantly greater forest canopy cover than the treated units. The thinned units also have significantly greater tree canopy cover than the thin-and-burn units. Winter season Landsat images have also been analyzed to calculate Normalized Difference Snow Index (NDSI), a key indicator of snow water equivalence and snow accumulation at the treated and untreated forests. The NDSI values from these dates are examined to determine if snow accumulation and snow water equivalence vary between treatments at our study sites. NDSI is significantly greater at the treated units than the control units. In particular, the thinned forest units have significantly greater snow cover than the control units. Our results indicate that forest restoration treatments result in increased snow pack

  17. Spatio-temporal features of vegetation restoration and variation after the Wenchuan earthquake with satellite images

    Science.gov (United States)

    Peng, Hou; Qiao, Wang; Yipeng, Yang; Weiguo, Jiang; Bingfeng, Yang; Qiang, Chen; Lihua, Yuan; Fanming, Kong; Xi, Chen; Guanjie, Wang

    2014-01-01

    The Wenchuan earthquake was a deadly earthquake that occurred on May 12, 2008, in Sichuan province of China. With the help of classic statistic methods, including arithmetic mean, standard deviation and linear trend estimation, vegetation restoration was recognized by analyzing spatio-temporal features of normalized difference vegetation index (NDVI) before and after this earthquake. Results indicate: (1) spatial distribution of NDVI mean values remains similar from 1998 to 2011. Higher values are mainly found in north, whereas lower values are mainly distributed over southeast, which is in good correlation with elevation and landform. Vegetation damage is at different levels in different seismic intensity (SI) regions: the higher SI is, the worse vegetation damage is. (2) Over the whole region, standard deviation is bigger after earthquake than before. Both absolute and relative changes in ecosystem stability increase with increasing SI. In different counties, variation of ecosystem stability is more obvious after earthquake, increase of standard deviation is approximately 6.5 times. Relatively, vegetation regionalization is the smallest analysis unit. Consequently, changes resulting from earthquake are unobvious. (3) Linear trend estimation coefficient increases from 0.0079 before the earthquake to 0.0359 after the earthquake in this whole region. This indicates that the plant ecosystem is rapidly restored between 2009 and 2011. The biggest linear trend is for the hill region, indicating good plant restoration and increase after earthquake. Fluctuation of linear trend estimation coefficient in different counties is more obvious after earthquake. Vegetation restoration after earthquake is most obvious in the regions that suffered the greatest SI (SI10 and SI11). In contrast, fluctuation in linear trend estimation coefficient of annual NDVI mean value for different classes of vegetation is more obvious before earthquake.

  18. TU-CD-BRA-12: Coupling PET Image Restoration and Segmentation Using Variational Method with Multiple Regularizations

    Energy Technology Data Exchange (ETDEWEB)

    Li, L; Tan, S [Huazhong University of Science and Technology, Wuhan, Hubei (China); Lu, W [University of Maryland School of Medicine, Baltimore, MD (United States)

    2015-06-15

    Purpose: To propose a new variational method which couples image restoration with tumor segmentation for PET images using multiple regularizations. Methods: Partial volume effect (PVE) is a major degrading factor impacting tumor segmentation accuracy in PET imaging. The existing segmentation methods usually need to take prior calibrations to compensate PVE and they are highly system-dependent. Taking into account that image restoration and segmentation can promote each other and they are tightly coupled, we proposed a variational method to solve the two problems together. Our method integrated total variation (TV) semi-blind deconvolution and Mumford-Shah (MS) segmentation. The TV norm was used on edges to protect the edge information, and the L{sub 2} norm was used to avoid staircase effect in the no-edge area. The blur kernel was constrained to the Gaussian model parameterized by its variance and we assumed that the variances in the X-Y and Z directions are different. The energy functional was iteratively optimized by an alternate minimization algorithm. Segmentation performance was tested on eleven patients with non-Hodgkin’s lymphoma, and evaluated by Dice similarity index (DSI) and classification error (CE). For comparison, seven other widely used methods were also tested and evaluated. Results: The combination of TV and L{sub 2} regularizations effectively improved the segmentation accuracy. The average DSI increased by around 0.1 than using either the TV or the L{sub 2} norm. The proposed method was obviously superior to other tested methods. It has an average DSI and CE of 0.80 and 0.41, while the FCM method — the second best one — has only an average DSI and CE of 0.66 and 0.64. Conclusion: Coupling image restoration and segmentation can handle PVE and thus improves tumor segmentation accuracy in PET. Alternate use of TV and L2 regularizations can further improve the performance of the algorithm. This work was supported in part by National Natural

  19. The optimal code searching method with an improved criterion of coded exposure for remote sensing image restoration

    Science.gov (United States)

    He, Lirong; Cui, Guangmang; Feng, Huajun; Xu, Zhihai; Li, Qi; Chen, Yueting

    2015-03-01

    Coded exposure photography makes the motion de-blurring a well-posed problem. The integration pattern of light is modulated using the method of coded exposure by opening and closing the shutter within the exposure time, changing the traditional shutter frequency spectrum into a wider frequency band in order to preserve more image information in frequency domain. The searching method of optimal code is significant for coded exposure. In this paper, an improved criterion of the optimal code searching is proposed by analyzing relationship between code length and the number of ones in the code, considering the noise effect on code selection with the affine noise model. Then the optimal code is obtained utilizing the method of genetic searching algorithm based on the proposed selection criterion. Experimental results show that the time consuming of searching optimal code decreases with the presented method. The restoration image is obtained with better subjective experience and superior objective evaluation values.

  20. In search for the original image: Luciano Freire and the theory and practice of painting restoration in Portugal circa 1900

    Directory of Open Access Journals (Sweden)

    António João Cruz

    2007-01-01

    Full Text Available From the fragmentary statements found in several texts, especially from a report written in the 1930's that presents memoir notes, this paper intends to reconstitute, as much as possible, the restoration theory and practice of Luciano Freire (1864-1934. He treated many of the most important paintings belonging to Portuguese museums and, according to his words, those interventions were justified, above all, by the damages caused by past restorers, through repaints, which was frequent, or through cleaning, which originated the worst problems, and by the damages caused by the ambient conditions surrounding the paintings. In general, the interventions aimed at recovering the original image. Although Luciano Freire was, in theory, an adept of the complete cleaning of dirt and varnishes and complete removal of retouches and repaints, as it was done in National Gallery, London, in practice he admitted that when the retouches and repaints were well done and in good condition they were not to be removed. He considered that losses should be reintegrated and his thoughts were divided by the recovering the original image and the respect for the original work. He usually ended up considering that mimetic retouching could only be done when enough clues were present. Therefore, retouching had limits that, however, he recognizes, he crossed at times. Although did not use radiographs, he attributed great importance to treatment documentation through photography or other means.

  1. Research on the Image Restoration of Fog and Haze%雾霾图像复原技术研究

    Institute of Scientific and Technical Information of China (English)

    陈阳; 李浩; 禹凤

    2015-01-01

    The phenomenon of haze causes low visibility, image blurring and color fading, thereby affecting subsequent processing of the image. By using dark channel prior and guided filtering, the haze recovery process to enhance the visibility of a series of images is successful. On the basis of the successful implementation of haze image restoration, deals with haze video by using time-domain information. Using time line information and dark channel prior method can effectively improve the efficiency of haze video processing and enhance the unity of fog and haze recovery video.%雾霾造成视野的限制,使图像模糊以及色彩淡化,进而影响图像的后续处理。利用暗通道先验和导向滤波方法能有效地进行雾霾图像复原,增强其可视性。在处理雾霾图像复原的基础上,对雾霾视频进行雾霾复原处理,利用时间轴信息的暗通道先验方法能有效提高雾霾视频处理的效率及增强处理后的雾霾复原视频的色调统一性。

  2. A novel structured dictionary for fast processing of 3D medical images, with application to computed tomography restoration and denoising

    Science.gov (United States)

    Karimi, Davood; Ward, Rabab K.

    2016-03-01

    Sparse representation of signals in learned overcomplete dictionaries has proven to be a powerful tool with applications in denoising, restoration, compression, reconstruction, and more. Recent research has shown that learned overcomplete dictionaries can lead to better results than analytical dictionaries such as wavelets in almost all image processing applications. However, a major disadvantage of these dictionaries is that their learning and usage is very computationally intensive. In particular, finding the sparse representation of a signal in these dictionaries requires solving an optimization problem that leads to very long computational times, especially in 3D image processing. Moreover, the sparse representation found by greedy algorithms is usually sub-optimal. In this paper, we propose a novel two-level dictionary structure that improves the performance and the speed of standard greedy sparse coding methods. The first (i.e., the top) level in our dictionary is a fixed orthonormal basis, whereas the second level includes the atoms that are learned from the training data. We explain how such a dictionary can be learned from the training data and how the sparse representation of a new signal in this dictionary can be computed. As an application, we use the proposed dictionary structure for removing the noise and artifacts in 3D computed tomography (CT) images. Our experiments with real CT images show that the proposed method achieves results that are comparable with standard dictionary-based methods while substantially reducing the computational time.

  3. Assessing the quality of restored images in optical long-baseline interferometry

    CERN Document Server

    Gomes, Nuno; Thiébaut, Éric

    2016-01-01

    Assessing the quality of aperture synthesis maps is relevant for benchmarking image reconstruction algorithms, for the scientific exploitation of data from optical long-baseline interferometers, and for the design/upgrade of new/existing interferometric imaging facilities. Although metrics have been proposed in these contexts, no systematic study has been conducted on the selection of a robust metric for quality assessment. This article addresses the question: what is the best metric to assess the quality of a reconstructed image? It starts by considering several metrics, and selecting a few based on general properties. Then, a variety of image reconstruction cases is considered. The observational scenarios are phase closure and phase referencing at the Very Large Telescope Interferometer (VLTI), for a combination of two, three, four and six telescopes. End-to-end image reconstruction is accomplished with the MiRA software, and several merit functions are put to test. It is found that convolution by an effect...

  4. Latest Methods of Image Enhancement and Restoration for Computed Tomography: A Concise Review

    Directory of Open Access Journals (Sweden)

    Zohair AL-AMEEN

    2015-03-01

    Full Text Available It is known that computed tomography (CT images are corrupted by many degradations including: blurring, low contrast or noise due to different real-world limitations. Thus, it is necessary to filter these images before starting the diagnostic process. In recent years, extensive research has been carried out to reduce such undesirable degradations, in which substantial achievements have been attained from skillful researchers by providing various innovative methods. Such methods contributed significantly in improving the poor visual quality of CT images. In this article, a review about six contemporary methods for each of image enhancement, denoising and deblurring is provided due to the high-profile of CT images in the medical field. Hence, after the prevalent causes of the degradations are highlighted, adequate elucidations about the literature methods are delivered. Finally, an inclusive summary is provided.

  5. Magnetic resonance image restoration via dictionary learning under spatially adaptive constraints.

    Science.gov (United States)

    Wang, Shanshan; Xia, Yong; Dong, Pei; Feng, David Dagan; Luo, Jianhua; Huang, Qiu

    2013-01-01

    This paper proposes a spatially adaptive constrained dictionary learning (SAC-DL) algorithm for Rician noise removal in magnitude magnetic resonance (MR) images. This algorithm explores both the strength of dictionary learning to preserve image structures and the robustness of local variance estimation to remove signal-dependent Rician noise. The magnitude image is first separated into a number of partly overlapping image patches. The statistics of each patch are collected and analyzed to obtain a local noise variance. To better adapt to Rician noise, a correction factor is formulated with the local signal-to-noise ratio (SNR). Finally, the trained dictionary is used to denoise each image patch under spatially adaptive constraints. The proposed algorithm has been compared to the popular nonlocal means (NLM) filtering and unbiased NLM (UNLM) algorithm on simulated T1-weighted, T2-weighted and PD-weighted MR images. Our results suggest that the SAC-DL algorithm preserves more image structures while effectively removing the noise than NLM and it is also superior to UNLM at low noise levels.

  6. Study of a new method for three-dimensional restoration from single image

    Institute of Scientific and Technical Information of China (English)

    XIE Ming-hong

    2009-01-01

    The aim of three-dimensional recovery technology from the image is to recover the relative height of each point on the surface from the light variations in the single image and carry out the recovery. A new method that recovers three-dimensional is presented object based on radius basis function for the image from the unknown light source direction, which constructs a surface equation by the network, uses the reflectivity function as a constraint, continuonsly estimates the light source direction in the self-learning process of the network from the bright spots around the spread of the image, and eventually obtains a satisfactory surface equation. This method makes the resumption of surface good continuity and smoothness, and can recover the height value of each network point of the image and be automatically inserted in any point the among the network. It is suitable for the image of Lambert reflection model and the image of the Specular reflection model and the mixed-reflex model.

  7. Assessing the quality of restored images in optical long-baseline interferometry

    Science.gov (United States)

    Gomes, Nuno; Garcia, Paulo J. V.; Thiébaut, Éric

    2017-03-01

    Assessing the quality of aperture synthesis maps is relevant for benchmarking image reconstruction algorithms, for the scientific exploitation of data from optical long-baseline interferometers, and for the design/upgrade of new/existing interferometric imaging facilities. Although metrics have been proposed in these contexts, no systematic study has been conducted on the selection of a robust metric for quality assessment. This article addresses the question: what is the best metric to assess the quality of a reconstructed image? It starts by considering several metrics and selecting a few based on general properties. Then, a variety of image reconstruction cases are considered. The observational scenarios are phase closure and phase referencing at the Very Large Telescope Interferometer (VLTI), for a combination of two, three, four and six telescopes. End-to-end image reconstruction is accomplished with the MIRA software, and several merit functions are put to test. It is found that convolution by an effective point spread function is required for proper image quality assessment. The effective angular resolution of the images is superior to naive expectation based on the maximum frequency sampled by the array. This is due to the prior information used in the aperture synthesis algorithm and to the nature of the objects considered. The ℓ1-norm is the most robust of all considered metrics, because being linear it is less sensitive to image smoothing by high regularization levels. For the cases considered, this metric allows the implementation of automatic quality assessment of reconstructed images, with a performance similar to human selection.

  8. Parallel ProXimal Algorithm for Image Restoration Using Hybrid Regularization

    CERN Document Server

    Pustelnik, Nelly; Pesquet, Jean-Christophe

    2009-01-01

    Regularization approaches have demonstrated their effectiveness for solving ill-posed problems. However, in the context of variational restoration methods, a challenging question remains, which is how to find a good regularizer. While total variation introduces staircase effects, wavelet domain regularization brings other artefacts, e.g. ringing. However, a compromise can be found by introducing a hybrid regularization including several terms non necessarily acting in the same domain (e.g. spatial and wavelet transform domains). We adopt a convex optimization framework where the criterion to be minimized is split in the sum of more than two terms. For spatial domain regularization, isotropic or anisotropic total variation definitions using various gradient filters are considered. An accelerated version of the Parallel ProXimal Algorithm is proposed to perform the minimization. Some difficulties in the computation of the proximity operators involved in this algorithm are also addressed in this paper. Numerical...

  9. Brain Phosphorus Magnetic Resonance Spectroscopy Imaging of Sleep Homeostasis and Restoration in Drug Dependence

    Directory of Open Access Journals (Sweden)

    George H. Trksak

    2007-01-01

    Full Text Available Numerous reports have documented a high occurrence of sleep difficulties in drug-dependent populations, prompting researchers to characterize sleep profiles and physiology in drug abusing populations. This mini-review examines studies indicating that drug-dependent populations exhibit alterations in sleep homeostatic and restoration processes in response to sleep deprivation. Sleep deprivation is a principal sleep research tool that results in marked physiological challenge, which provides a means to examine sleep homeostatic processes in response to extended wakefulness. A report from our laboratory demonstrated that following recovery sleep from sleep deprivation, brain high-energy phosphates particularly beta–nucleoside triphosphate (beta-NTP are markedly increased as measured with phosphorus magnetic resonance spectroscopy (MRS. A more recent study examined the effects of sleep deprivation in opiate-dependent methadone-maintained (MM subjects. The study demonstrated increases in brain beta-NTP following recovery sleep. Interestingly, these increases were of a markedly greater magnitude in MM subjects compared to control subjects. A similar study examined sleep deprivation in cocaine-dependent subjects demonstrating that cocaine-dependent subjects exhibit greater increases in brain beta-NTP following recovery sleep when compared to control subjects. The studies suggest that sleep deprivation in both MM subjects and cocaine-dependent subjects is characterized by greater changes in brain ATP levels than control subjects. Greater enhancements in brain ATP following recovery sleep may reflect a greater disruption to or impact of sleep deprivation in drug dependent subjects, whereby sleep restoration processes may be unable to properly regulate brain ATP and maintain brain high-energy equilibrium. These studies support the notion of a greater susceptibility to sleep loss in drug dependent populations. Additional sleep studies in drug abusing

  10. Low-Rank Decomposition Based Restoration of Compressed Images via Adaptive Noise Estimation.

    Science.gov (United States)

    Zhang, Xinfeng; Lin, Weisi; Xiong, Ruiqin; Liu, Xianming; Ma, Siwei; Gao, Wen

    2016-07-07

    Images coded at low bit rates in real-world applications usually suffer from significant compression noise, which significantly degrades the visual quality. Traditional denoising methods are not suitable for the content-dependent compression noise, which usually assume that noise is independent and with identical distribution. In this paper, we propose a unified framework of content-adaptive estimation and reduction for compression noise via low-rank decomposition of similar image patches. We first formulate the framework of compression noise reduction based upon low-rank decomposition. Compression noises are removed by soft-thresholding the singular values in singular value decomposition (SVD) of every group of similar image patches. For each group of similar patches, the thresholds are adaptively determined according to compression noise levels and singular values. We analyze the relationship of image statistical characteristics in spatial and transform domains, and estimate compression noise level for every group of similar patches from statistics in both domains jointly with quantization steps. Finally, quantization constraint is applied to estimated images to avoid over-smoothing. Extensive experimental results show that the proposed method not only improves the quality of compressed images obviously for post-processing, but are also helpful for computer vision tasks as a pre-processing method.

  11. Accurate measurement of respiratory airway wall thickness in CT images using a signal restoration technique

    Science.gov (United States)

    Park, Sang Joon; Kim, Tae Jung; Kim, Kwang Gi; Lee, Sang Ho; Goo, Jin Mo; Kim, Jong Hyo

    2008-03-01

    Airway wall thickness (AWT) is an important bio-marker for evaluation of pulmonary diseases such as chronic bronchitis, bronchiectasis. While an image-based analysis of the airway tree can provide precise and valuable airway size information, quantitative measurement of AWT in Multidetector-Row Computed Tomography (MDCT) images involves various sources of error and uncertainty. So we have developed an accurate AWT measurement technique for small airways with three-dimensional (3-D) approach. To evaluate performance of these techniques, we used a set of acryl tube phantom was made to mimic small airways to have three different sizes of wall diameter (4.20, 1.79, 1.24 mm) and wall thickness (1.84, 1.22, 0.67 mm). The phantom was imaged with MDCT using standard reconstruction kernel (Sensation 16, Siemens, Erlangen). The pixel size was 0.488 mm × 0.488 mm × 0.75 mm in x, y, and z direction respectively. The images were magnified in 5 times using cubic B-spline interpolation, and line profiles were obtained for each tube. To recover faithful line profile from the blurred images, the line profiles were deconvolved with a point spread kernel of the MDCT which was estimated using the ideal tube profile and image line profile. The inner diameter, outer diameter, and wall thickness of each tube were obtained with full-width-half-maximum (FWHM) method for the line profiles before and after deconvolution processing. Results show that significant improvement was achieved over the conventional FWHM method in the measurement of AWT.

  12. FFT-Based Methods for Nonlinear Image Restoration in Confocal Microscopy

    NARCIS (Netherlands)

    Roerdink, J.B.T.M.

    1994-01-01

    Recently we developed a new method for attenuation correction in 3D imaging by a confocal scanning laser microscope (CSLM) in the (epi)fluorescence mode. The fundamental element in our approach consisted of multiplying the measured fluorescent intensity by a correction factor involving a convolution

  13. Restorative treatment thresholds for interproximal primary caries based on radiographic images: findings from the Dental Practice-Based Research Network

    DEFF Research Database (Denmark)

    Gordan, Valeria V; Garvan, Cynthia W; Heft, Marc W

    2009-01-01

    with restorative intervention in lesions that have penetrated only the enamel surface. This study surveyed dentists from the Dental Practice-Based Research Network (DPBRN) who had reported doing at least some restorative dentistry (n = 901). Dentists were asked to indicate the depth at which they would restore...

  14. Continuous evaluation of land cover restoration of tsunami struck plains in Japan by using several kinds of optical satellite image in time series

    Science.gov (United States)

    Hashiba, H.

    2015-09-01

    The Mw 9.0 earthquake that struck Japan in 2011 was followed by a large-scale tsunami in the Tohoku region. The damage in the coastal plane was extensively displayed through many satellite images. Furthermore, satellite imaging is requested for the ongoing evaluation of the restoration process. The reconstruction of the urban structure, farmlands, grassland, and coastal forest that collapsed under the large tsunami requires effective long-term monitoring. Moreover, the post-tsunami land cover dynamics can be effectively modeled using time-constrained satellite data to establish a prognosis method for the mitigation of future tsunami impact. However, the remote satellite capture of a long-term restoration process is compromised by accumulating spatial resolution effects and seasonal influences. Therefore, it is necessary to devise a method for data selection and dataset structure. In the present study, the restoration processes were investigated in four years following the disaster in a part of the Sendai plain, northeast Japan, from same-season satellite images acquired by different optical sensors. Coastal plains struck by the tsunami are evaluated through land-cover classification processing using the clustering method. The changes in land cover are analyzed from time-series optical images acquired by Landsat-5/TM, 7/ETM+, 8/OLI, EO-1/ALI, and ALOS-1/AVNIR-2. The study reveals several characteristics of the change in the inundation area and signs of artificial and natural restoration.

  15. Dynamic positron emission tomography image restoration via a kinetics-induced bilateral filter.

    Directory of Open Access Journals (Sweden)

    Zhaoying Bian

    Full Text Available Dynamic positron emission tomography (PET imaging is a powerful tool that provides useful quantitative information on physiological and biochemical processes. However, low signal-to-noise ratio in short dynamic frames makes accurate kinetic parameter estimation from noisy voxel-wise time activity curves (TAC a challenging task. To address this problem, several spatial filters have been investigated to reduce the noise of each frame with noticeable gains. These filters include the Gaussian filter, bilateral filter, and wavelet-based filter. These filters usually consider only the local properties of each frame without exploring potential kinetic information from entire frames. Thus, in this work, to improve PET parametric imaging accuracy, we present a kinetics-induced bilateral filter (KIBF to reduce the noise of dynamic image frames by incorporating the similarity between the voxel-wise TACs using the framework of bilateral filter. The aim of the proposed KIBF algorithm is to reduce the noise in homogeneous areas while preserving the distinct kinetics of regions of interest. Experimental results on digital brain phantom and in vivo rat study with typical (18F-FDG kinetics have shown that the present KIBF algorithm can achieve notable gains over other existing algorithms in terms of quantitative accuracy measures and visual inspection.

  16. Synthesis and functionalization of a triaryldiamine-base photoconductive/photorefractive composite, and its application to aberrated image restoration

    Science.gov (United States)

    Liang, Yichen

    Organic phoorefractive (PR) composites have recently emerged as an important class of materials for applications including high-density data storage, optical communication, and biomedical imaging. In an effort to further improve their performance, this study focused on the utilization of functionalized semiconductor nanocrystals to photosensitize triaryamine (TPD)-based PR composites, as well as the application of TPD-based PR composites in the restoration of aberrated optical information. A novel approach to functionalize CdSe quantum dot (QCdSe) was firstly introduced where the sulfonated triarydiamine (STPD) was used as charge-transporting ligand to passivate QCdSe. TPD-based photoconductive and PR composites were photosensitized with the STPD-passivated QCdSe (SQCdSe). Due to the charge-transporting capability of STPD, the composites photosensitized with STPD-capped QCdSe exhibited superior performance relative to composites employing more traditional photosensitizers (such as fullerene C60 and trioctylphosphine-capped QCdSe), with figures-of-merit including photoconductivities in excess of 60 pS/cm, two-beam coupling gain coefficients in excess of 110 cm-1, and PR response time of less than 30 ms. In addition, the ability of TPD-based PR composites to correct aberrations associated with a laser beam was described. Here, a severely aberrated laser beam was able to be restored to a nearly unaberrated condition through the PR process, and the potential of this technique for practical applications was well explained. Based on the current experimental geometry, a PR response time of 0.5 s was observed, which is the fastest PR response time reported for a PR composite operating under experimental conditions designed for the correction of optical aberrations.

  17. 基于模拟方法的水下图像复原%Underwater image restoration based on simulation method

    Institute of Scientific and Technical Information of China (English)

    鲁国春; 聂武; 张赫

    2011-01-01

    采用模板假设、离焦模糊和大气湍流干扰3种退化模型模拟散射过程,对水下图像进行复原.试验表明,模拟方法可行,复原图像质量有明显改善,可为水下图像散射退化机理研究提供参考.%Three degradation models such as template hypothesis,defocus blur and atmospheric turbulence interference were used to simulate scattering process, and restore underwater image.Experiments show that the simulation methods are feasible,and the restored image is improved obviously,which can give reference for scattering mechanism research of underwater image degradation.

  18. Study of frequency pattern of coherent turbulent flow over ripples using image processing with implication in river restoration

    Directory of Open Access Journals (Sweden)

    A. Keshavarzi

    2011-08-01

    Full Text Available River channel change and bed scourings are source of major environmental problem for fish and aquatic habitat. The bed form such as ripples and dunes is the result of an interaction between turbulent flow structure and sediment particles at the bed. The structure of turbulent flow over ripples is important to understand initiation of sediment entrainment and its transport. The focus of this study is the measurement and analysis of the dominant bursting events and the flow structure over ripples in the bed of a channel. Two types of ripples with sinusoidal and triangular forms were tested in this study. The velocities of flow over the ripples were measured in three dimensions using an Acoustic Doppler Velocimeter with a sampling rate of 50 Hz. These velocities were measured at different points within the flow depth from the bed and at different longitudinal positions along the flume. A CCD camera was used to capture 1500 sequential images from the bed and to monitor sediment movement at different positions along the bed. Application of image processing technique enabled us to compute the number of entrained and deposited particles over the ripples. From a quadrant decomposition of instantaneous velocity fluctuations close to the bed, it was found that bursting events downstream of the second ripple, in Quadrants 1 and 3, were dominant whereas upstream of the ripple, Quadrants 2 and 4 were dominant. More importantly consideration of these results indicates that the normalized occurrence probabilities of sweep events are in phase with the bed forms whereas those of ejection event are out of phase with the bed form. Therefore entrainment would be expected to occur upstream and deposition occurs downstream of the ripple. These expectations were confirmed by measurement of entrained and deposited sediment particles from the bed. These above information can be used in practical application for rivers where restoration is required.

  19. 被动毫米波图像恢复的偏微分方程方法%Partial Differential Equation Method for Passive Millimeter Wave Image Restoration

    Institute of Scientific and Technical Information of China (English)

    王本庆; 李兴国

    2009-01-01

    For the problem that passive millimeter wave (MMW) image is fuzzy and of low resolution,the par-tial differential equation (PDE) method is proposed for high-resolution restoration of the image and then the PDE model and the corresponsive image restoration algorithm are given. First, this method denoises the obtained blurred image by using two Gauss function of different scale parameter to get two images which are more blurred,and then obtain the high-resolution image using iteration from the two images. This PDE algorithm is of simple principle and convenient calculation. Passive MMW image restoration of an actual metal target shows that this method is effective.%针对被动毫米波图像模糊和分辨率较低,提出采用偏微分方程方法进行图像的高分辨率恢复,并给出了偏微分方程模型和相应的图像恢复算法.该方法首先把得到的带噪降晰图像进行两个不同尺度的 Gauss 去噪,获得两幅更模糊的再降晰图像,再以这两幅图像为基础,通过迭代计算得到高分辨率图像.偏微分方程方法原理简单并且计算方便,通过对实际金属目标的被动毫米波图像的恢复,显示该方法具有较好的恢复效果.

  20. Restorative treatment thresholds for interproximal primary caries based on radiographic images: findings from the Dental Practice-Based Research Network

    DEFF Research Database (Denmark)

    Gordan, Valeria V; Garvan, Cynthia W; Heft, Marc W

    2009-01-01

    with restorative intervention in lesions that have penetrated only the enamel surface. This study surveyed dentists from the Dental Practice-Based Research Network (DPBRN) who had reported doing at least some restorative dentistry (n = 901). Dentists were asked to indicate the depth at which they would restore...... that they would restore a proximal enamel lesion, while 24% would do so once the lesion had reached into the outer third of the dentin. For a low caries risk patient, 39% of respondents reported that they would restore an enamel lesion, and 54% would do so once the lesion had reached into the outer third...... of the dentin. In multivariate analyses that accounted for dentist and practice characteristics, dentists in large group practices were less likely to intervene surgically for enamel caries, regardless of patient's caries risk....

  1. Efficient restoration of variable area soundtracks:

    OpenAIRE

    Abdelâali Hassaïne; Etienne Decencière; Bernard Besserer

    2009-01-01

    The restoration of motion picture films using digital image processing has been an active research field for many years. The restoration of the soundtrack however, has mainly been performed in the sound domain, using signal processing methods, in spite of the fact that it is recorded as a continuous image between the images of the film and the perforations. In this paper a restoration method for variable area soundtrack restoration at the image level is presented. First, a novel method is pro...

  2. Efficient restoration of variable area soundtracks:

    OpenAIRE

    Abdelâali Hassaïne; Etienne Decencière; Bernard Besserer

    2009-01-01

    The restoration of motion picture films using digital image processing has been an active research field for many years. The restoration of the soundtrack however, has mainly been performed in the sound domain, using signal processing methods, in spite of the fact that it is recorded as a continuous image between the images of the film and the perforations. In this paper a restoration method for variable area soundtrack restoration at the image level is presented. First, a novel method is pro...

  3. Image Denoising Using Total Variation Model Guided by Steerable Filter

    Directory of Open Access Journals (Sweden)

    Wenxue Zhang

    2014-01-01

    Full Text Available We propose an adaptive total variation (TV model by introducing the steerable filter into the TV-based diffusion process for image filtering. The local energy measured by the steerable filter can effectively characterize the object edges and ramp regions and guide the TV-based diffusion process so that the new model behaves like the TV model at edges and leads to linear diffusion in flat and ramp regions. This way, the proposed model can provide a better image processing tool which enables noise removal, edge-preserving, and staircase suppression.

  4. Blocked-regularized Gmres method of image restoration%图像恢复的分块正则化 Gmres 方法

    Institute of Scientific and Technical Information of China (English)

    陈亚文; 闵涛

    2013-01-01

    利用分块Gmres算法在处理大规模线性方程组时具有的优势,将其同正则化技术相结合应用于图像恢复领域,提出一种新的图像恢复的方法。该方法考虑了图像恢复中的时间复杂度与空间复杂度2个方面。数值模拟时,对不同的方法进行了对比分析,结果表明所提出的方法能够明显改善图像恢复的质量。%The blocked Gmres algorithm has certain superiority in dealing with the large systems of linear equations ,a new algorithm to combine the regularization algorithm with blocked Gmres algorithm in im-age restoration filed is proposed .T he algorithm considers the time and space complexity in image restora-tion .In the numerical simulation ,different methods are compared ,the results show that the method can significantly improves the quality of image restoration .

  5. A piecewise monotone subgradient algorithm for accurate L¹-TV based registration of physical slices with discontinuities in microscopy.

    Science.gov (United States)

    Michalek, Jan; Capek, Martin

    2013-05-01

    Image registration tasks are often formulated in terms of minimization of a functional consisting of a data fidelity term penalizing the mismatch between the reference and the target image, and a term enforcing smoothness of shift between neighboring pairs of pixels (a min-sum problem). Most methods for deformable image registration use some form of interpolation between matching control points. The interpolation makes it impossible to account for isolated discontinuities in the deformation field that may appear, e.g., when a physical slice of a microscopy specimen is ruptured by the cutting tool. For registration of neighboring physical slices of microscopy specimens with discontinuities, Janácek proposed an L¹-distance data fidelity term and a total variation (TV) smoothness term, and used a graph-cut (GC) based iterative steepest descent algorithm for minimization. The L¹-TV functional is nonconvex; hence a steepest descent algorithm is not guaranteed to converge to the global minimum. Schlesinger presented transformation of max-sum problems to minimization of a dual quantity called problem power, which is--contrary to the original max-sum functional--convex. Based on Schlesinger's solution to max-sum problems we developed an algorithm for L¹-TV minimization by iterative multi-label steepest descent minimization of the convex dual problem. For Schlesinger's subgradient algorithm we proposed a novel step control heuristics that considerably enhances both speed and accuracy compared with standard step size strategies for subgradient methods. It is shown experimentally that our subgradient scheme achieves consistently better image registration than GC in terms of lower values both of the composite L¹-TV functional, and of its components, i.e., the L¹ distance of the images and the transformation smoothness TV, and yields visually acceptable results even in cases where the GC based algorithm fails. The new algorithm allows easy parallelization and can thus be

  6. Quantitative Assessment of a Novel Super-Resolution Restoration Technique Using HiRISE with Navcam Images: how much Resolution Enhancement is Possible from Repeat-Pass Observations

    Science.gov (United States)

    Tao, Y.; Muller, J.-P.

    2016-06-01

    Higher spatial resolution imaging data is always desirable to the international community of planetary scientists interested in improving understanding of surface formation processes. We have previously developed a novel Super-resolution restoration (SRR) technique (Tao & Muller, 2016) using Gotcha sub-pixel matching, orthorectification, and segmented 4th order PDE-TV, called GPT SRR, which is able to restore 5 cm-12.5 cm near rover scale images (equivalent to Navcam projected FoV at a range of ≥ 5 m) from multiple 25 cm resolution NASA MRO HiRISE images. The SRR technique has been successfully applied to the rover traverses for the MER and MSL missions within the EU FP-7 PRoViDE project. These SRR results have revealed new surface information including the imaging of individual rocks (diameter ≥ 25 cm) by comparison of the original HiRISE image and rover Navcam orthorectified image mosaics. In this work, we seek evidence from processing a very large number of stereo reconstruction results from all Navcam stereo images within PRoViDE, registration and comparison with the corresponding SRR image, in order to derive a quantitative assessment on key features including rocks (diameter < 150 cm) and rover track wheel spacing. We summarise statistics from SRR-Navcam measurements and demonstrate that our unique SRR datasets will greatly support the geological and morphological analysis and monitoring of Martian surface and can also be applied to landing site selection, in order to avoid unsuitable terrain, for any future lander/rover as well as help to define future rover paths.

  7. 大气湍流模糊图像的高分辨力复原算法%High resolution restoration algorithm of atmospheric turbulence blurred image

    Institute of Scientific and Technical Information of China (English)

    李思雯; 徐超; 刘广荣; 金伟其

    2013-01-01

    大气湍流是大气中的一种重要运动形式,它的存在使大气中的动量、热量、水气和污染物的垂直和水平交换作用明显增强,这种干扰作用极大地影响了光电成像系统对于目标的分辨能力。由于湍流影响而退化的图像中同时存在着“幸运区域”,用适当的算法可以获得高分辨力复原图像。为了获取包含“幸运区域”的大气湍流模糊图像,在实验室使用人造湍流,并结合短曝光技术拍摄了大气湍流干扰的序列图像。文中应用矩形交叠分块方法,改进了基于偏微分方程(PDE′s)的序列图像复原算法,对获取的序列短曝光图像进行处理。结果表明,经该算法处理得到的合成图像质量有明显的提升,该算法对大气湍流造成的图像质量退化有较好的复原作用。%Atmospheric turbulence is an important form of movement in the atmosphere, which makes the vertical and horizontal′s exchange interaction of momentum, heat, water vapor and pollutants significantly enhanced, and this interference has a great impact on the target resolution of optical imaging system. There also have "lucky regions" in the degraded images because of turbulence, so the appropriate algorithm can obtain high resolution restored image. To obtain the atmospheric turbulence blurred images which contains "lucky regions", the artificial turbulence was used in the laboratory and combined with the short-exposure technique to take a serial of atmospheric turbulence blurred images. The rectangle overlapped partition method was used and the image restoration algorithm was improved based on nonlinear partial-derivative equations (PDE′s), to process the obtained short exposure serial images. The results show that, the image quality of the composite image is improved obviously, this algorithm has great restoration effect on images′ quality degradation caused by atmospheric turbulence.

  8. Document Image Restoration Using Bayesian Inference Method%基于文档图像的贝叶斯重建算法仿真研究

    Institute of Scientific and Technical Information of China (English)

    郭皎; 鄢沛

    2011-01-01

    研究文档图像的分辨率提高问题,针对数字化文档图像在采集过程中遇到的低分辨率、噪声、纸张质量蜕化和形变等因素影响,提出了一种新的贝叶斯估计的最大后验概率算法对文档图像进行恢复和重构.首先利用聚类方法对文档中文字进行自动分类,然后依据每个类别中相同字符的先验知识,例如出现频率,几何特性等,利用一个能量方程来求取最终的MAP最优解,然后一个新颖的MAP迭代算法,反复利用对高分辨率图像的估计来逼近最优解,从而使得最终的高分辨率字符图像获得很高的清晰度.仿真结果表明提出的算法能稳定地提高文字的分辨率,提高文档的识别准确率,并且具有高的运算效率.在此基础上利用本文方法,可以方便的实现多文档或者书籍图像的重建和恢复.%Restoration of documents is a key step for applications in document processing, retrieval understanding as well as digital libraries, for example as in book readers. In this paper, we present a method to restore document images, by using a Maximum a Posteriori ( MAP) framework. The prior probability of the characters is learned from the training document images. The extraction of a single high-quality enhanced text image from a set of degraded images can benefit from a strong prior knowledge. The restoration process should allow for discontinuities and discourage oscillations at the same time. These properties were represented in a total variation based prior model. Results indicate that our method is appropriate for document image restoration, where resolution enhancement is an added gain.

  9. Accelerated gradient methods for total-variation-based CT image reconstruction

    DEFF Research Database (Denmark)

    Jørgensen, Jakob Heide; Jensen, Tobias Lindstrøm; Hansen, Per Christian

    2011-01-01

    Total-variation (TV)-based CT image reconstruction has shown experimentally to be capable of producing accurate reconstructions from sparse-view data. In particular TV-based reconstruction is very well suited for images with piecewise nearly constant regions. Computationally, however, TV-based....... In the present work we address the question of how to reduce the number of gradient method iterations needed to achieve a high-accuracy TV reconstruction. We consider the use of two accelerated gradient-based methods, GPBB and UPN, to solve the 3D-TV minimization problem in CT image reconstruction. The former...... incorporates several heuristics from the optimization literature such as Barzilai-Borwein (BB) step size selection and nonmonotone line search. The latter uses a cleverly chosen sequence of auxiliary points to achieve a better convergence rate. The methods are memory efficient and equipped with a stopping...

  10. Restoration of Throwing Soil Motion-Blurred Images%土粒流运动图像模糊退化的恢复

    Institute of Scientific and Technical Information of China (English)

    李伯全; 陈翠英

    2001-01-01

    It describes the motion-blurred images of back-throwing latent soil under up-cut rotary cultivation. Mathematics models of the process are set up and several methods of restoration of the motion-blurred images are discussed. According to the characteristics and causes of the motion-blurred images of back-throw soil, different restoration methods are adopted. In this paper, wienerfilter with optimal windows is used to set different areas of the images and to determine point spread function of each image. A quite satisfactory result is achieved. The study will reduce the difficulty and improve accuracy in the late image processing.%分析了潜土逆转旋耕被抛土粒流运动图像模糊退化机理,依据土粒流运动图像的特点,针对不同的退化机理分别采用了不同的恢复方法. 该文采用带最优窗的维纳滤波恢复方法,对土粒流运动模糊退化图像适当进行分区,确定了合适于各自图像区域的点扩展函数,获得了较为满意的恢复效果,为降低后续处理的难度和提高处理精度提供了可靠保证.

  11. Restoring proximal caries lesions conservatively with tunnel restorations

    Directory of Open Access Journals (Sweden)

    Chu CH

    2013-07-01

    Full Text Available Chun-Hung Chu1, May L Mei,1 Chloe Cheung,1 Romesh P Nalliah2 1Faculty of Dentistry, The University of Hong Kong, Hong Kong, People's Republic of China; 2Department of Restorative Dentistry and Biomaterials Sciences, Harvard School of Dental Medicine, Boston, MA, USA Abstract: The tunnel restoration has been suggested as a conservative alternative to the conventional box preparation for treating proximal caries. The main advantage of tunnel restoration over the conventional box or slot preparation includes being more conservative and increasing tooth integrity and strength by preserving the marginal ridge. However, tunnel restoration is technique-sensitive and can be particularly challenging for inexperienced restorative dentists. Recent advances in technology, such as the contemporary design of dental handpieces with advanced light-emitting diode (LED and handheld comfort, offer operative dentists better vision, illumination, and maneuverability. The use of magnifying loupes also enhances the visibility of the preparation. The advent of digital radiographic imaging has improved dental imaging and reduced radiation. The new generation of restorative materials has improved mechanical properties. Tunnel restoration can be an option to restore proximal caries if the dentist performs proper case selection and pays attention to the details of the restorative procedures. This paper describes the clinical technique of tunnel restoration and reviews the studies of tunnel restorations. Keywords: operative, practice, tunnel preparation, composite, amalgam, glass ionomer

  12. Signal restoration method for restraining the range walk error of Geiger-mode avalanche photodiode lidar in acquiring a merged three-dimensional image.

    Science.gov (United States)

    Xu, Lu; Zhang, Yu; Zhang, Yong; Wu, Long; Yang, Chenghua; Yang, Xu; Zhang, Zijing; Zhao, Yuan

    2017-04-10

    The fluctuation in the number of signal photoelectrons will cause a range walk error in a Geiger-mode avalanche photodiode (Gm-APD) lidar, which significantly depends on the target intensity. For a nanosecond-pulsed laser, the range walk error of traditional time-of-flight will cause deterioration. A new signal restoration method, based on the Poisson probability response model and the center-of-mass algorithm, is proposed to restrain the range walk error. We obtain a high-precision depth and intensity merged 3D image using this method. The range accuracy is 0.6 cm, and the intensity error is less than 3%.

  13. New algorithm to determine true colocalization in combination with image restoration and time-lapse confocal microscopy to MAP kinases in mitochondria.

    Directory of Open Access Journals (Sweden)

    Jorge Ignacio Villalta

    Full Text Available The subcellular localization and physiological functions of biomolecules are closely related and thus it is crucial to precisely determine the distribution of different molecules inside the intracellular structures. This is frequently accomplished by fluorescence microscopy with well-characterized markers and posterior evaluation of the signal colocalization. Rigorous study of colocalization requires statistical analysis of the data, albeit yet no single technique has been established as a standard method. Indeed, the few methods currently available are only accurate in images with particular characteristics. Here, we introduce a new algorithm to automatically obtain the true colocalization between images that is suitable for a wide variety of biological situations. To proceed, the algorithm contemplates the individual contribution of each pixel's fluorescence intensity in a pair of images to the overall Pearsońs correlation and Manders' overlap coefficients. The accuracy and reliability of the algorithm was validated on both simulated and real images that reflected the characteristics of a range of biological samples. We used this algorithm in combination with image restoration by deconvolution and time-lapse confocal microscopy to address the localization of MEK1 in the mitochondria of different cell lines. Appraising the previously described behavior of Akt1 corroborated the reliability of the combined use of these techniques. Together, the present work provides a novel statistical approach to accurately and reliably determine the colocalization in a variety of biological images.

  14. 结合局部与非局部的图像复原方法%Combining local and nonlocal method for image restoration

    Institute of Scientific and Technical Information of China (English)

    李俊英; 肖升

    2015-01-01

    In order to recover the details better, this paper proposed a new image restoration method, which combined the lo-cal total variation (LTV) and the nonlocal total variation (NLTV) models.First, it extracted the details accurately from the image.Then, the method applied the NLTV model only on the details, and applied the LTV model only on the residual image components.The proposed method, which used the advantages of both the LTV and NLTV models, could recover the image details better.A large number of experimental results indicate that the proposed method outperforms several recent image resto-ration methods, not only the subjective vision has the betterment obviously, but also the PSNR improves between 0.11 dB and 2.28 dB.%为了更好地复原图像的细节,提出了一种结合局部与非局部的图像复原方法。将图像中的细节准确地提取出来,对提取的细节进行非局部全变差约束,同时对剩下的图像成分进行局部全变差约束。提出的方法很好地结合了非局部全变差和局部全变差的优点,实现了图像细节更好的复原。实验结果表明,提出的方法与近几年的一些较好的图像复原方法相比,不仅主观的视觉效果得到了明显的改进,而且客观的峰值信噪比也增加了0.11~2.28 dB。

  15. Voice restoration

    NARCIS (Netherlands)

    Hilgers, F.J.M.; Balm, A.J.M.; van den Brekel, M.W.M.; Tan, I.B.; Remacle, M.; Eckel, H.E.

    2010-01-01

    Surgical prosthetic voice restoration is the best possible option for patients to regain oral communication after total laryngectomy. It is considered to be the present "gold standard" for voice rehabilitation of laryngectomized individuals. Surgical prosthetic voice restoration, in essence, is alwa

  16. 变分框架下的多尺度图像恢复与重建%Multiscale Image Restoration and Reconstruction in the Framework of Variation

    Institute of Scientific and Technical Information of China (English)

    唐利明; 黄大荣

    2013-01-01

    变分图像分解,通过极小化能量泛函将图像分解为不同的特征分量,可以被应用到图像的恢复和重建。提出了变分框架下的多尺度图像恢复和重建的思想。基于这种思想,首先提出了一个单参数的(BV ,G ,E )三元变分分解模型,并且理论分析了参数与不同特征分量的尺度的关系。然后将此模型的参数选为一个二进制序列,得到多尺度的(BV ,G ,E )变分分解。该多尺度变分分解可以将图像分解为一序列图像结构、纹理和噪声。证明了此多尺度分解的收敛性并且基于对偶理论和交替迭代算法给出了其数值求解方法。最后将提出的多尺度的(BV ,G ,E )变分分解应用到图像恢复和重建,实验结果证实了理论分析的正确性,显示了将此模型进行图像多尺度恢复和重建的有效性,和与一些其他分解模型相比较的优越性。%By minimizing the energy functional ,we can obtain the variational image decomposition which decomposes image into different characteristic components ,and can be used for image restoration and reconstruction .An idea of multiscale image restoration and reconstruction in the framework of variation is proposed .Based on this idea ,firstly ,a single-parameter (BV ,G ,E ) trituple decomposition model is proposed ,and the relationship between the parameter and the scale of each component is studied the-oretically .And then ,by replacing the parameter with a binary sequence ,we achieve a multiscale (BV ,G ,E) decomposition which can decompose an image into a sequence of image structure ,texture and noise .The convergence of this multiscale decomposition is proved ,and an efficient numerical method based on the duality theory and alternate iteration algorithm is introduced to solve it .At last ,the proposed multiscale (BV ,G ,E ) decomposition is applied for image restoration and reconstruction .Numerical results sup-port the

  17. The acceptability of TV-based game platforms as an instrument to support the cognitive evaluation of senior adults at home

    Science.gov (United States)

    Rivas Costa, Carlos; Anido Rifón, Luis Eulogio; Gómez Carballa, Miguel; Valladares Rodríguez, Sonia

    2017-01-01

    interest in keeping the system at home after the pilot. Besides, these perceptions are fairly stable in time as shown by the survey performed 36 months after pilot testing. Limitations Although participating users are a representative sample of the Galician population, which in turn is comparable to the population of most rural areas in Europe, a larger and more diverse user sample would be needed to obtain significant results for a wider population profile. Conclusion The study confirmed the technical acceptance, that is, the perceived usefulness and perceived ease of use, of the TV-based home technical setting introduced as a means of cognitive evaluation. This study provides initial evidence on the viability of a TV-based serious games approach for cognitive longitudinal screening at home with little intervention of clinical professionals, thus contributing to the early detection of cognitive impairments in the senior population. PMID:28070464

  18. The acceptability of TV-based game platforms as an instrument to support the cognitive evaluation of senior adults at home

    Directory of Open Access Journals (Sweden)

    Carlos Rivas Costa

    2017-01-01

    expressed their interest in keeping the system at home after the pilot. Besides, these perceptions are fairly stable in time as shown by the survey performed 36 months after pilot testing. Limitations Although participating users are a representative sample of the Galician population, which in turn is comparable to the population of most rural areas in Europe, a larger and more diverse user sample would be needed to obtain significant results for a wider population profile. Conclusion The study confirmed the technical acceptance, that is, the perceived usefulness and perceived ease of use, of the TV-based home technical setting introduced as a means of cognitive evaluation. This study provides initial evidence on the viability of a TV-based serious games approach for cognitive longitudinal screening at home with little intervention of clinical professionals, thus contributing to the early detection of cognitive impairments in the senior population.

  19. Restoring forests

    DEFF Research Database (Denmark)

    Jacobs, Douglass F.; Oliet, Juan A.; Aronson, James

    2015-01-01

    of land requiring restoration implies the need for spatial prioritization of restoration efforts according to cost-benefit analyses that include ecological risks. To design resistant and resilient ecosystems that can adapt to emerging circumstances, an adaptive management approach is needed. Global change......, in particular, imparts a high degree of uncertainty about the future ecological and societal conditions of forest ecosystems to be restored, as well as their desired goods and services. We must also reconsider the suite of species incorporated into restoration with the aim of moving toward more stress resistant...... and competitive combinations in the longer term. Non-native species may serve an important role under some circumstances, e.g., to facilitate reintroduction of native species. Propagation and field establishment techniques must promote survival through seedling stress resistance and site preparation. An improved...

  20. Restoration of dichromatic images gained from CCD/CMOS camera by iterative detection networks with fragmented marginalization at the symbol block level

    Science.gov (United States)

    Kekrt, Daniel; Klíma, Miloš; Fliegel, Karel

    2009-08-01

    Image capturing by CCD/CMOS cameras is encumbered with two fundamental perturbing influences. Time invariant blurring (image convolution with fixed kernel) and time variant noises. Both of these influences can be successfully eliminated by the iterative detection networks (IDNs), that effectively and suboptimally (iteratively) solve 2D MAP criterion through the image decomposition to the small areas. Preferably to the individual pixel level, if this allows the noise distribution (statistically independent noise). Nevertheless, this task is so extremely numerically exacting and therefore the contemporary IDNs are limited only for restorations of dichromatic images. The IDNs are composed of certain, as simple as possible, statistical devices (SISO modules) and can be separated into two basic groups with variable topology (exactly matched to the blurring kernel) and with fixed topology, same for all possible kernels. The paper deals with second group of IDNs, concretely with IDNs whose SISO modules are concatenated in three directions (horizontal, vertical and diagonal). Advantages of such ordering rests in the application flexibility (can be comfortable applied to many irregular cores) and also in the low exigencies to number of memory devices it the IDN. The mentioned IDN type will be implemented in the two different variants suppressing defocusing in the lens of CCD/CMOS sensing system and will be verified in the sphere of a dichromatic 2D barcode detection.

  1. 无源毫米波成像改进POCS超分辨率算法%Passive Millimeter-Wave Image Restoration Based on Improved POCS Algorithm

    Institute of Scientific and Technical Information of China (English)

    赵康; 王建国

    2011-01-01

    The problem of poor resolution of acquired image in the passive millimeter wave imaging stems mainly from antenna size limitations. Thus efficient post-processing is necessary to achieve resolution improvements. The algorithm combines the advantages of Wiener filter restoration algorithm and POCS algorithm based on convex set theoretic. The Wiener filter is employed to restore the pass-band spectrum, and the POCS algorithm is applied to complete spectral extrapolation as the main iterative process to ensure that low-frequency component is not destroyed as spectral extrapolating. Experimental results demonstrate the algorithm improves the convergent rate and is computationally much more efficient than POCS algorithm. The algorithm is easily implemented in real time for passive millimeter wave imaging.%在无源毫米波成像中,因为受天线孔径大小的限制而导致获取的图像分辨率低,所以必须采取有效后处理措施增强分辨率.提出了一种改进的POCS超分辨率算法,该算法结合了Wiener滤波器复原算法和凸集投影(POCS)算法的优点,使用Wiener滤波复原算法恢复图像通带内的低频分量,运用POCS算法作为主迭代过程实现频谱外推,同时保证低频分量不被破坏.实验结果表明,该算法增强了图像的分辨率,改善了收敛速度,减少了计算量,有利于无源毫米波成像超分辨率的实时实现.

  2. 自适应非局部patch正则化图像恢复%Adaptive Nonlocal Patch Regularization for Image Restoration

    Institute of Scientific and Technical Information of China (English)

    刘红毅; 韦志辉; 张峥嵘

    2012-01-01

    Nonlocal means exploits the spatial correlation in an image, and preserves the structure information effectively. Combining the nonlocal patch regularization with TV regularization, we propose a nonlocal patch regularized image restoration model.The improved structure tensor matrix can be used to achieve a data-adaptive weigh function, which can then adjust the similarity match process based on the local structure of a pixel. A more simple and effective algorithm -Split Bregman, is used to solve the model iteratively. Compared with other regularization models, our method performs better in improving the quality of restoration image and the efficiency of the algorithm.%非局部均值利用图像自相似性,有效保持了图像的几何结构信息.提出了非局部patch正则和TV正则结合的图像恢复模型,利用改进的结构张量矩阵构造自适应非局部权函数,根据像素的局部结构计算图像中patch的相似性,提高了图像结构信息的保持性能.在数值解法上,采用分裂Bregman算法迭代求解模型,得到简单快速的迭代形式.数值实验证明所提出方法在提高恢复图像质量和算法效率上都有显著改进.

  3. Restoration of Medical Images with Different Types of Noise; Restauracion de Imagenes Medicas con Diferentes Tipos de Ruido

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez, M. G.; Vidal, V.; Verdu, G.; Mayo, P.; Rodenas, F.

    2013-07-01

    In this paper, a method is proposed to reduce the Gaussian, speckle and impulsive noise. This filter, named PGMFDNL filter combines a nonlinear diffusion and fuzzy peer group. The proposed filter can effectively reduce image noise without any information about the noise present in the image. As a result, the proposed method obtains good performance in different types of noise.

  4. 使用幸运成像技术恢复地基大口径望远镜图像%Restoration of astronomical images using lucky imaging technique on ground-based large telescope

    Institute of Scientific and Technical Information of China (English)

    赵金宇; 张世学; 王斌

    2012-01-01

    开发了一套地基大口径望远镜上的幸运成像系统,以完成对空间目标图像的恢复.系统由5部分组成:预处理、帧选择、图像配准、图像重建和图像增强.对于点目标图像,系统使用斯特列尔比做为像质评价函数,配准算法使用最亮点匹配或质心匹配;对于扩展目标图像,系统采用Fisher信息值或SOBEL算子函数进行像质评价,图像配准采用基于GPU的傅里叶-梅林变换及SIFT匹配算法.用户还可以根据目标图像的特点手动选定图像,并选择合适的配准算法.该幸运成像系统已经成功地应用在1.23 m望远镜的成像探测中,并取得了较为理想的实验结果,成功地获取了月表、木星等空间目标的清晰图像.实验结果表明,该幸运成像系统可以显著地提高通过大气湍流的成像分辨率.%A lucky imaging system was developed to restore astronomical images through atmosphere turbulence on ground-based large aperture telescope. The system mainly consisted of five parts: preprocessing, frame selection, image registration, image reconstruction and image enhancement. For point objects, Strehl ratio was used instantaneous as an image quality metric, and the brightest point or centroid matching was used as the image registration method; for extended objects, a Fisher information or a Sobel operator based metric was used, and a GPU based Fourier-Mellin transform or SIFT algorithm was used to make a robust registration. To guarantee the stability of this system, it also allowed the users to select the frames manually and chose the appropriate calibration method. This lucky imaging system was successfully applied to restore the astronomical images taken by a 1.23 m telescope. The clear images of moon surface and Jupiter were got. The experimental results show that this system can be demonstrated to greatly improve the imaging resolution through atmospheric turbulence.

  5. A New Algorithm for Restoration of Fog-degraded Images%雾天降质图像的去雾复原新算法

    Institute of Scientific and Technical Information of China (English)

    张鑫; 麻金继; 吴浩

    2015-01-01

    For the fog visible images with low contrast and poor imaging conditions,we propose a new algorithm for the foggy images.The algorithm based on a priori knowledge of Dark Channel and combining with Guided Filter Function greatly solves the problem of inaccurate scene transmittance of the images due to the heavy haze.Compared to the results of Dark Channel Priori,the effect of the restoration of this algorithm is obvious,which not only restores the contour and color information of foggy scenes,but also different materials of the objects can be better performed.The results of de-hazing enhance the visibility of the image and make it closer to the real scene.Meanwhile,under heavy fog weather conditions,the ability to defog is significant.The algorithm with high computational efficiency can greatly reduce the complexity of de-hazing.%针对雾天可见光图像对比度低,成像效果差的情况,提出了一种图像去雾新算法。该算法在暗原色先验知识的基础上,结合引导滤波函数,解决了雾天图像场景透射率不精确的问题。算法结果与暗原色先验方法得到的结果相比,复原效果明显,不仅还原了雾天场景的轮廓和颜色信息,而且对不同材质的物体表现更佳,使得去雾后图像的可视性增强,更加贴近真实场景。同时,对于浓雾天气条件下获取的图像,去雾能力显著,计算效率更高,大大降低了去雾算法的复杂程度。

  6. 雾天偏振成像影响分析及复原方法研究%Analysis and restoration research of fog polarization imaging

    Institute of Scientific and Technical Information of China (English)

    汪杰君; 杨杰; 张文涛; 王新强; 叶松

    2016-01-01

    为了抑制雾天图像质量的退化,基于大气散射物理模型及偏振图像暗通道原理,提出了一种改进的雾天偏振遥感图像去雾算法.首先依据大气散射模型对雾天偏振成像机理进行分析,对大气偏振信息对去雾的影响进行了阐述.其次利用边缘检测和闭运算自动获取雾天偏振图像的天空区域,估算无穷远大气光强和大气偏振度.最后,针对图像中存在的噪声干扰等因素,修正大气偏振度及大气光强,恢复了退化图像的辐射强度信息.通过理论分析和实验验证,取得了较好的雾天图像复原结果.结果表明,该算法可以准确获取天空区域,实现更高鲁棒性的天空区域估计方法,有效提高图像的对比度和清晰度,增加图像细节,改善雾天图像的质量.该算法能够有效抑制雾天对图像造成的退化,从而提高遥感的目标探测和识别能力.%To solve the quality degradation problem of fog polarization imaging, an improved defogging method was proposed based on physical model of atmospheric scattering and dark passage principle of polarization images. Firstly, based on atmospheric scattering model, fog polarization imaging mechanism was analyzed and effect of atmospheric polarization on defogging was explained. Secondly, based on edge detection operator and closing operation, sky region of fog polarization image was obtained, and light intensity of infinity atmospheric and degree of polarization of atmospheric were estimated. At last, to solve the existing factors in the image such as noise interference, radiation intensity information of the degraded image was restored by modifying the degree of polarization and light intensity distribution of atmospheric. After theoretical analysis and experimental verification, good results of foggy image restoration were achieved. The results show that the algorithm can accurately obtain the sky region and improve the contrast and sharpness of the image, and

  7. ramic restorations

    Directory of Open Access Journals (Sweden)

    Ashish R Jain

    2013-01-01

    Full Text Available Rehabilitation of a patient with severely worn dentition after restoring the vertical dimension is a complex procedure and assessment of the vertical dimension is an important aspect in these cases. This clinical report describes the full mouth rehabilitation of a patient who was clinically monitored to evaluate the adaptation to a removable occlusal splint to restore vertical dimension for a period 1 month and provisional restorations to determine esthetic and functional outcome for a period of 3 months. It is necessary to recognizing that form follows function and that anterior teeth play a vital role in the maintenance of oral health. Confirmation of tolerance to changes in the vertical dimension of occlusion (VDO is of paramount importance. Articulated study casts and a diagnostic wax-up can provide important information for the evaluation of treatment options. Alteration of the VDO should be conservative and should not be changed without careful consideration.

  8. Sub-diffraction limit localization of proteins in volumetric space using Bayesian restoration of fluorescence images from ultrathin specimens.

    Directory of Open Access Journals (Sweden)

    Gordon Wang

    Full Text Available Photon diffraction limits the resolution of conventional light microscopy at the lateral focal plane to 0.61λ/NA (λ = wavelength of light, NA = numerical aperture of the objective and at the axial plane to 1.4nλ/NA(2 (n = refractive index of the imaging medium, 1.51 for oil immersion, which with visible wavelengths and a 1.4NA oil immersion objective is -220 nm and -600 nm in the lateral plane and axial plane respectively. This volumetric resolution is too large for the proper localization of protein clustering in subcellular structures. Here we combine the newly developed proteomic imaging technique, Array Tomography (AT, with its native 50-100 nm axial resolution achieved by physical sectioning of resin embedded tissue, and a 2D maximum likelihood deconvolution method, based on Bayes' rule, which significantly improves the resolution of protein puncta in the lateral plane to allow accurate and fast computational segmentation and analysis of labeled proteins. The physical sectioning of AT allows tissue specimens to be imaged at the physical optimum of modern high NA plan-apochormatic objectives. This translates to images that have little out of focus light, minimal aberrations and wave-front distortions. Thus, AT is able to provide images with truly invariant point spread functions (PSF, a property critical for accurate deconvolution. We show that AT with deconvolution increases the volumetric analytical fidelity of protein localization by significantly improving the modulation of high spatial frequencies up to and potentially beyond the spatial frequency cut-off of the objective. Moreover, we are able to achieve this improvement with no noticeable introduction of noise or artifacts and arrive at object segmentation and localization accuracies on par with image volumes captured using commercial implementations of super-resolution microscopes.

  9. Environmental Restoration

    Energy Technology Data Exchange (ETDEWEB)

    Zeevaert, T.; Vanmarcke, H

    1998-07-01

    The objectives of SCK-CEN's programme on environmental restoration are (1) to optimize and validate models for the impact assessment from environmental, radioactive contaminations, including waste disposal or discharge; (2) to support the policy of national authorities for public health and radioactive waste management. Progress and achievements in 1997 are reported.

  10. Site Restoration

    Energy Technology Data Exchange (ETDEWEB)

    Noynaert, L.; Bruggeman, A.; Cornelissen, R.; Massaut, V.; Rahier, A

    2001-04-01

    The objectives, the programme, and the achievements of the Site Restoration Department of SCK-CEN in 2000 are summarised. Main activities include the decommissioning of the BR3 PWR-reactor as well as other clean-up activities, projects on waste minimisation and activities related to the management of decommissioning projects. The department provides consultancy and services to external organisations.

  11. Restorative neuroscience

    DEFF Research Database (Denmark)

    Andres, Robert H; Meyer, Morten; Ducray, Angélique D

    2008-01-01

    There is increasing interest in the search for therapeutic options for diseases and injuries of the central nervous system (CNS), for which currently no effective treatment strategies are available. Replacement of damaged cells and restoration of function can be accomplished by transplantation of...

  12. Application of Retinex in Color Restoration of Image Enhancement to Night Scene Image%Retinex在夜景影像增强处理中的色彩补偿应用

    Institute of Scientific and Technical Information of China (English)

    吴静; 王子武

    2014-01-01

    Many monitoring and reconnaissance images are shot in night without auxiliary light,so those images are usually very dim and need enhancement processing which can be realized by Retinex with a good effect,but Retinex needs the color restoration. Based on the contrastive analysis of the RGB and the HSI color space,the differences,advantages and disadvantages are compared considering the transformation of Retinex algorithm from the RGB to the HSI to construct the SSRHSI algorithm to obtain the new effect on the color restoration.%很多监控和侦察影像,都是在夜晚无辅助光的条件下所拍摄的,该影像通常非常昏暗,需要做增强处理,Retinex可以对其做增强处理,并表现良好,但需要色彩补偿。对RGB和HSI色彩空间做对比分析,比较了两者之间差别和优缺点,考虑将Retinex算法从RGB转换到HSI色彩域,构建SSRHSI算法,以期在色彩补偿方面得到新的效果。

  13. 育种遗传算法及其在图像恢复中的应用%Breed Genetic Algorithm and Application of Image Restoration

    Institute of Scientific and Technical Information of China (English)

    马国强; 刘娟

    2009-01-01

    提出一种新的育种遗传算法用于模糊图像的恢复.采用在解空间产生均匀分布初始种群和最优值保留策略.每代个体依优劣按比例分成雌雄两性.随机产生一部分雌性个体直接进入下一代种群.按照育种学理论,一个雄性与多个雌性进行级进杂交,雄性进行自交.初始种群的规模和两性比例调控全局搜索能力,杂交时雌雄双方遗传比例调控收敛速度.图像恢复实验表明,本算法具有强鲁棒性,种群进化快,能快速提高图像质量.%A new breeding genetic algorithm with population uniformity in the whole solution space and elitist strategy is proposed to use for image restoration. All individuals of each generation are pro rata divided into males and females based on their values of the fitness function. During the evolution, the individuals of the next generation are generated by three kinds of ways: one way is to randomly select several females from the current population, the other way is to conform to the breeding theory to generate the children by cross several females with one male or by cross one male with another male. The global search ability is controlled by the population size and the proportion of male to female. And the convergence rate is controlled by the proportion of chromosome afforded by males and females on hybridization. The experimental results of image restoration show that the proposed algorithm is robust, and can rapidly improve the image's quality.

  14. Computationally efficient video restoration for Nyquist sampled imaging sensors combining an affine-motion-based temporal Kalman filter and adaptive Wiener filter.

    Science.gov (United States)

    Rucci, Michael; Hardie, Russell C; Barnard, Kenneth J

    2014-05-01

    In this paper, we present a computationally efficient video restoration algorithm to address both blur and noise for a Nyquist sampled imaging system. The proposed method utilizes a temporal Kalman filter followed by a correlation-model based spatial adaptive Wiener filter (AWF). The Kalman filter employs an affine background motion model and novel process-noise variance estimate. We also propose and demonstrate a new multidelay temporal Kalman filter designed to more robustly treat local motion. The AWF is a spatial operation that performs deconvolution and adapts to the spatially varying residual noise left in the Kalman filter stage. In image areas where the temporal Kalman filter is able to provide significant noise reduction, the AWF can be aggressive in its deconvolution. In other areas, where less noise reduction is achieved with the Kalman filter, the AWF balances the deconvolution with spatial noise reduction. In this way, the Kalman filter and AWF work together effectively, but without the computational burden of full joint spatiotemporal processing. We also propose a novel hybrid system that combines a temporal Kalman filter and BM3D processing. To illustrate the efficacy of the proposed methods, we test the algorithms on both simulated imagery and video collected with a visible camera.

  15. Pollination and Restoration

    National Research Council Canada - National Science Library

    Kingsley W. Dixon

    2009-01-01

    Pollination services underpin sustainability of restored ecosystems. Yet, outside of agri-environments, effective restoration of pollinator services in ecological restoration has received little attention...

  16. A dual method for maximum entropy restoration

    Science.gov (United States)

    Smith, C. B.

    1979-01-01

    A simple iterative dual algorithm for maximum entropy image restoration is presented. The dual algorithm involves fewer parameters than conventional minimization in the image space. Minicomputer test results for Fourier synthesis with inadequate phantom data are given.

  17. Bayesian methods to restore and re build images: application to gamma-graphy and to photofission tomography; Methodes bayesiennes pour la restauration et la reconstruction d`images application a la gammagraphie et a la tomographie par photofissions

    Energy Technology Data Exchange (ETDEWEB)

    Stawinski, G

    1998-10-26

    Bayesian algorithms are developed to solve inverse problems in gamma imaging and photofission tomography. The first part of this work is devoted to the modeling of our measurement systems. Two models have been found for both applications: the first one is a simple conventional model and the second one is a cascaded point process model. EM and MCMC Bayesian algorithms for image restoration and image reconstruction have been developed for these models and compared. The cascaded point process model does not improve significantly the results previously obtained by the classical model. To original approaches have been proposed, which increase the results previously obtained. The first approach uses an inhomogeneous Markov Random Field as a prior law, and makes the regularization parameter spatially vary. However, the problem of the estimation of hyper-parameters has not been solved. In the case of the deconvolution of point sources, a second approach has been proposed, which introduces a high level prior model. The picture is modeled as a list of objects, whose parameters and number are unknown. The results obtained with this method are more accurate than those obtained with the conventional Markov Random Field prior model and require less computational costs. (author)

  18. Investigation of cone-beam CT image quality trade-off for image-guided radiation therapy

    Science.gov (United States)

    Bian, Junguo; Sharp, Gregory C.; Park, Yang-Kyun; Ouyang, Jinsong; Bortfeld, Thomas; El Fakhri, Georges

    2016-05-01

    It is well-known that projections acquired over an angular range slightly over 180° (so-called short scan) are sufficient for fan-beam reconstruction. However, due to practical imaging conditions (projection data and reconstruction image discretization, physical factors, and data noise), the short-scan reconstructions may have different appearances and properties from the full-scan (scans over 360°) reconstructions. Nevertheless, short-scan configurations have been used in applications such as cone-beam CT (CBCT) for head-neck-cancer image-guided radiation therapy (IGRT) that only requires a small field of view due to the potential reduced imaging time and dose. In this work, we studied the image quality trade-off for full, short, and full/short scan configurations with both conventional filtered-backprojection (FBP) reconstruction and iterative reconstruction algorithms based on total-variation (TV) minimization for head-neck-cancer IGRT. Anthropomorphic and Catphan phantoms were scanned at different exposure levels with a clinical scanner used in IGRT. Both visualization- and numerical-metric-based evaluation studies were performed. The results indicate that the optimal exposure level and number of views are in the middle range for both FBP and TV-based iterative algorithms and the optimization is object-dependent and task-dependent. The optimal view numbers decrease with the total exposure levels for both FBP and TV-based algorithms. The results also indicate there are slight differences between FBP and TV-based iterative algorithms for the image quality trade-off: FBP seems to be more in favor of larger number of views while the TV-based algorithm is more robust to different data conditions (number of views and exposure levels) than the FBP algorithm. The studies can provide a general guideline for image-quality optimization for CBCT used in IGRT and other applications.

  19. 基于K-SVD的偏微分方程模型在毫米波图像恢复中的应用%Application of PDE model based on K-SVD in millimeter wave image restoration

    Institute of Scientific and Technical Information of China (English)

    尚丽; 苏品刚

    2012-01-01

    When an image contaminated by large noise or with lower resolution is processed by the traditional Partial Differential Equation (PDE) model, the stable solutions of PDE can generate a distinct step effect and the restored image's quality is relatively poor. Therefore, a new PDE image restoration method based on K-Singular Value Decomposition (K-SVD) was proposed and used successfully to restore MilliMeter Wave (MMW) image. K-SVD was a sparse representation method of images. An image can be denoised when it is sparsely estimated by K-SVD. Especially, for images with large noise variance, K-SVD has better denoising robustness. At first, the MMW image was denoised by /C-SVD, and then PDE method based on Total Variation (TV) was utilized to restore the denoised images obtained by K-SVD. In test, a simulated MMW image and a real MMW image were used respectively to testify the proposed algorithm, and then the results were compared with those of K-"SVD and PDE. At the same time, the Pick Signal-to-Noise Ratio (PSNR) criterion was used to measure restored images. In terms of PSNR values and the vision effect of restored images with different noise variance, the simulation results show that the proposed method can efficiently denoise MMW images.%在图像被大噪声污染或具有较低分辨率时,传统的偏微分方程(PDE)模型的稳态解会产生明显的阶梯效应,恢复图像质量较差.针对此缺点,提出了一种新的基于K-奇异值分解(K-SVD)的PDE图像恢复方法,并应用于毫米波(M MW)图像的恢复.K-SVD是一种图像稀疏表示方法,对图像进行稀疏估计的同时实现去噪,对噪声方差较大的图像具有较好的去噪鲁棒性.首先采用K-SVD对MMW图像进行去噪,对去噪图像再应用全变分(TV)模型的PDE方法进行恢复.对所提出的算法分别使用模拟的MMW图像和真实的MMW图像进行测试,并进一步和K-SVD、PDE方法比较,同时使用峰值信噪比(PSNR)对恢复图像进行评价.根

  20. EFFICIENT RESTORATION OF VARIABLE AREA SOUNDTRACKS

    Directory of Open Access Journals (Sweden)

    Abdelâali Hassaïne

    2011-05-01

    Full Text Available The restoration of motion picture films using digital image processing has been an active research field for many years. The restoration of the soundtrack however, has mainly been performed in the sound domain, using signal processing methods, in spite of the fact that it is recorded as a continuous image between the images of the film and the perforations. In this paper a restoration method for variable area soundtrack restoration at the image level is presented. First, a novel method is proposed for the detection of the symmetry axis of the scanned soundtrack. Then, a comparison between the watershed and the region growing segmentation of the soundtrack is developed. Another algorithm aiming to enforce the symmetry and to correct the edges of the segmented image is presented. A last step aiming to smooth the edges of the obtained image is performed. Finally, experimental results are reported and possible future improvements are discussed.

  1. Site Restoration

    Energy Technology Data Exchange (ETDEWEB)

    Noynaert, L.; Bruggeman, A.; Cornelissen, R.; Massaut, V.; Rahier, A

    2002-04-01

    The objectives, the programme, and the achievements of SCK-CEN's Site Restoration Department for 2001 are described. Main activities include the decommissioning of the BR3 PWR-reactor as well as other clean-up activities, projects on waste minimisation and the management of spent fuel and the flow of dismantled materials and the recycling of materials from decommissioning activities based on the smelting of metallic materials in specialised foundries. The department provides consultancy and services to external organisations and performs R and D on new techniques including processes for the treatment of various waste components including the reprocessing of spent fuel, the treatment of tritium, the treatment of liquid alkali metals into cabonates through oxidation, the treatment of radioactive organic waste and the reconditioning of bituminised waste products.

  2. 量子行为粒子群算法在图像恢复中的应用%The Application of Quantum-behaved Particle Swarm Optimization in Image Restoration

    Institute of Scientific and Technical Information of China (English)

    山艳; 陈昊

    2013-01-01

    遗传算法等智能搜索技术避免了图像恢复方法中存在的较多约束和计算量过大的问题,但遗传算法存在“过早收敛”现象。作为一种新的智能优化算法-量子行为粒子群优化算法,在全局收敛性和稳定性上有较好的表现。文章提出了一种基于量子行为粒子群算法的图像恢复方法,并与基于标准遗传算法的图像恢复进行了比较。仿真结果表明,该算法可使图像恢复结果和效率得以较大的改善和提高,具有推广应用价值。%The intelligent search technologies, such as genetic algorithms, avoid the problems of too many restrictions and complex computation in image restoration, but genetic algorithms may early convergent. Quantum-behaved Particle Swarm Optimization as a new method of optimization is better in convergence and stability of the overall. The article presents a method based on quantum-behaved particle swarm optimization in image restoration, compared with the method of genetic algorithms in image restoration. The simulation results indicate that this scheme can improve the performance and efifciency of image restoration, and that the algorithm is of great value in extension and application.

  3. Restoration of Irregular Sampled Remote Sensing Image Based on NLTV%基于NLTV的消除不规则采样遥感图像复原方法

    Institute of Scientific and Technical Information of China (English)

    徐焕宇; 孙权森; 夏德深

    2012-01-01

    This paper proposes an image restoration algorithm for remote sensing images to eliminate irregular sampling effect. The algorithm combines the ACT algorithm and the total variation to restore several degradation artifacts, and integrates the nonlocal means operator to propose a remote sensing image restoration model based on nonlocal total variation to eliminate irregular sampling effect, then uses operator splitting method and extended Chambolle’s projection algorithm to solve the model. Experimental results show that the proposed algorithm can reduce the staircase effect effectively and improve the detail information of the restored image.%提出一种消除不规则采样的遥感图像复原方法,该方法结合了 ACT 算法和总变差(TV)图像复原模型以达到同时去除多种图像退化因素的目的,并且结合非局部均值(NLM)算子给出了基于 NLTV 的消除不规则采样遥感图像复原模型,最后使用算子分裂与扩展的坎贝尔投影算法求解模型。试验结果表明,该方法能够有效减少复原图像的阶梯效应并提高复原图像的纹理细节信息。

  4. Digital non-metric image-based documentation for the preservation and restoration of mural paintings: the case of the Üzümlü Rock-hewn Church, Turkey

    OpenAIRE

    Ryo Higuchi; Tamaki Suzuki; Mina Shibata; Yoko Taniguchi; Murat Gülyaz

    2016-01-01

    Digital photography is a valuable documentation technique for the preservation of a cultural heritage site because highresolution photography presents both general and detailed views of mural paintings and mural condition in a single image. Advanced digital technology is particularly helpful for preserving and restoring mural paintings given that the painting condition is recorded on high-resolution base maps shows how mural paintings are damaged by environmental stresses, mechanical damages ...

  5. Restoration of variable density film soundtracks

    OpenAIRE

    Besserer, Bernard; Etienne, Decencière; Hassaïne, Abdelâali

    2009-01-01

    Full text available at http://www.eurasip.org/Proceedings/Eusipco/Eusipco2009/contents/papers/1569192297.pdf; International audience; The restoration of motion picture films has been an active research field for many years. The restoration of the soundtrack however has mainly been performed at the audio domain in spite of the fast that it is recorded as a continuous image on the film stock. In this paper, we propose a new restoration method for variable density soundtracks. The method first d...

  6. MMW image restoration based on the combination of NNSC shrinkage technique and modified four-order PDE model%组合NNSC收缩技术和改进四阶PDE的MMW图像恢复

    Institute of Scientific and Technical Information of China (English)

    尚丽; 苏品刚; 颜廷秦; 淮文军

    2013-01-01

    A millimeter wave (MMW) image contains much unknown noise, and the restoration quality is worse only using sole method. Combined the advantages of non - negative sparse coding (NNSC) shrinkage technique and modified four - order partial differential equation (PDE), a combination based MMW image restoration method is proposed. The NNSC shrinkage method behaves adaptive property of denoising and is irrelative to the data attribute. The modified four - order PDE can delete the stair- casing effect, generated by the two- order PDE, and avoid the un- smoothing phenomenon of flat region, and behaves the better effect on image restoration. Utilizing respectively the simulated and true MMW image to test and the relative signal noise ratio (RSNR) to measure the quality of restored results, and compared with methods of NNSC shrinkage, four- order PDE and wavelet shrinkage, experimental results show that the method proposed here is efficient in the MMW image restoration.%毫米波(MMW)图像含有大量未知噪声,仅用一种方法恢复的效果较差,因此结合非负稀疏编码(NNSC)收缩技术和改进四阶偏微分方程(PDE)模型的优点,提出了一种基于组合处理的MMW图像恢复方法.NNSC收缩法具有自适应消噪图像的特性,和数据的属性无关;而改进四阶PDE能够消除二阶PDE产生的阶梯效应,同时避免光滑区域不平整的现象,具有较好的图像恢复效果.分别采用模拟的和真实的MMW图像进行测试,并用相对信噪比(RSNR)进行评判,实验表明,与NNSC收缩、基于四阶的PDE模型以及小波收缩等方法相比,所提出的方法能够有效地用于MMW图像的恢复.

  7. 基于引导滤波器的单幅雾天图像复原算法%Novel algorithm for single haze image restoration based on guided image filtering

    Institute of Scientific and Technical Information of China (English)

    楚君; 王华彬; 陶亮; 周健

    2015-01-01

    The single image dehazing method based on median filtering neither effectively preserves edges of haze image nor truly reflects the depth of the scene information. So this paper proposes a method of atmospheric veil correction based on guided image filtering. It gets the initial atmospheric veil through median filtering. It is refined by guided image filter to obtain more accurate atmospheric veil. It removes redundant texture information and brings the depth edge information. The scene radiation is obtained by the atmosphere attenuation model, adjusting the brightness of the restored image. Com-pared with other existing typical dehazing methods, the method has a better dehazing effect at distant object where depth changes abruptly, and the time complexity of the methods is linear.%基于中值滤波的单幅图像去雾算法所获取的大气面纱图像不能有效地保留雾天图像的边缘信息,也不能真实地反映场景的深度信息,因此,提出了一种基于引导滤波器的大气面纱修正方法。由中值滤波得到初始大气面纱,使用引导图像滤波器对其进行修正得到较为准确的大气面纱,去除多余的纹理信息的同时增强了雾天图像的边缘信息,由大气散射模型得到场景辐射光即复原图像,并对其进行亮度调整。与其他现有的典型去雾算法相比较,该算法在深度剧烈变化的边缘区域有更好的去雾和增强效果,且时间复杂度为线性。

  8. TV-based conjugate gradient method and discrete L-curve for few-view CT reconstruction of X-ray in vivo data

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Xiaoli; Hofmann, Ralf; Dapp, Robin; van de Kamp, Thomas; Rolo, Tomy dos Santos; Xiao, Xianghui; Moosmann, Julian; Kashef, Jubin; Stotzka, Rainer

    2015-01-01

    High-resolution, three-dimensional (3D) imaging of soft tissues requires the solution of two inverse problems: phase retrieval and the reconstruction of the 3D image from a tomographic stack of two-dimensional (2D) projections. The number of projections per stack should be small to accommodate fast tomography of rapid processes and to constrain X-ray radiation dose to optimal levels to either increase the duration of in vivo time-lapse series at a given goal for spatial resolution and/or the conservation of structure under X-ray irradiation. In pursuing the 3D reconstruction problem in the sense of compressive sampling theory, we propose to reduce the number of projections by applying an advanced algebraic technique subject to the minimisation of the total variation (TV) in the reconstructed slice. This problem is formulated in a Lagrangian multiplier fashion with the parameter value determined by appealing to a discrete L-curve in conjunction with a conjugate gradient method. The usefulness of this reconstruction modality is demonstrated for simulated and in vivo data, the latter acquired in parallel-beam imaging experiments using synchrotron radiation. (C) 2015 Optical Society of America

  9. Prosthesis-guided implant restoration of an auricular defect using computed tomography and 3-dimensional photographic imaging technologies: a clinical report.

    Science.gov (United States)

    Wang, Shuming; Leng, Xu; Zheng, Yaqi; Zhang, Dapeng; Wu, Guofeng

    2015-02-01

    The concept of prosthesis-guided implantation has been widely accepted for intraoral implant placement, although clinicians do not fully appreciate its use for facial defect restoration. In this clinical report, multiple digital technologies were used to restore a facial defect with prosthesis-guided implantation. A simulation surgery was performed to remove the residual auricular tissue and to ensure the correct position of the mirrored contralateral ear model. The combined application of computed tomography and 3-dimensional photography preserved the position of the mirrored model and facilitated the definitive implant-retained auricular prosthesis.

  10. Digital non-metric image-based documentation for the preservation and restoration of mural paintings: the case of the Üzümlü Rock-hewn Church, Turkey

    Directory of Open Access Journals (Sweden)

    Ryo Higuchi

    2016-05-01

    Full Text Available Digital photography is a valuable documentation technique for the preservation of a cultural heritage site because highresolution photography presents both general and detailed views of mural paintings and mural condition in a single image. Advanced digital technology is particularly helpful for preserving and restoring mural paintings given that the painting condition is recorded on high-resolution base maps shows how mural paintings are damaged by environmental stresses, mechanical damages and inappropriate treatments, among others. In addition, photogrammetric software technology is rapidly advancing and being applied to the digital documentation of mural paintings or rock art. Nevertheless, human experience and investigation of mural paintings is indispensable for recording the condition of mural paintings, and this highlights that every step of documentation conducted in situ is desirable. However, images by photogrammetric software do not show sufficient resolution because most normal portable computers used on-site are not usually sufficient. Based on our experience at the Üzümlü Church in Cappadocia, Turkey, we propose a new approach to document mural conditions in situ for preservation and restoration. Our method is based on a comparison of a non-metric but approximate high-resolution image with the actual mural paintings. The method does not require special instruments and enables digital documentation of the mural condition in situ at a low cost, in a short time frame and using minimal human resources.

  11. 基于结构因子和颜色聚类的墓葬图像修复算法%Restoring Algorithm of the Tomb Image Based on Structure Factor and Color Glustering

    Institute of Scientific and Technical Information of China (English)

    刘英杰; 杨风暴; 刘冰清

    2015-01-01

    Image of the tomb mural has rich color , once destroyed it will lose a lot of structural information . Traditional algorithms restoring such image haven ’ t considered the priority of accurate restoration of strong structur-al information which results in repair area over extended and incoherent .To solve this problem , an image restora-tion algorithm based on structure factor and color clustering is proposed .Firstly, structure factor items are added in the priority calculation of repairing block .Secondly , search for similar block by color FCM clustering algorithm . Finally, depending on the size relationship between average sum of squared differences ( ASSD) and the set thresh-old, adaptively adjust the size of the repair block to achieve accurate matching of complex structure of the region . Experimental results show that a method of image restoration for the Northern Qi Dynasty tomb murals has a good re-sult.Compared with Criminisi algorithm , structural similarity ( SSIM) upgrades at least 5.68%.%墓葬壁画图像颜色丰富,一旦破损会丢失大量结构信息。传统算法修复此类图像时,没有考虑图像强结构信息的优先精确修复,造成修复区域的过延伸和不连贯。针对上述问题,提出了一种基于结构因子和颜色聚类的墓葬图像修复算法。算法首先在待修复块优先级计算中加入结构因子项;其次,通过颜色FCM聚类算法划分区域进行相似块精确搜索;最后,根据均值像素差平方和( ASSD)与设定阈值的大小关系,自适应地对修复块尺寸进行调整以实现复杂结构区域的精确匹配。实验结果表明,所提方法对北齐墓葬壁画图像大面积缺损有很好的修复效果,与Criminisi算法比较,在结构相似度( SSIM)上至少提升5.68%。

  12. 基于改进湍流模型和偏振成像技术的水下退化图像复原方法%Restoring method for underwater degraded images based on improved turbulence model and polarization imaging

    Institute of Scientific and Technical Information of China (English)

    王马华; 赵正敏; 王士湖; 季仁东

    2013-01-01

      为了满足工厂化水产养殖中过程控制的信息化要求,该文提出一种基于改进湍流模型结合偏振成像技术,具有较强鲁棒性的水下退化图像复原方法。考虑内外尺度对波结构函数影响,结合折射率谱,改进水下湍流退化模型以提高复原算法先验知识的完备性;基于改进的退化模型和水下前向散射光的偏振特性,利用偏振成像技术提取退化图像中的噪声特征;基于退化图像噪声特征,采用约束最小二乘滤波法进行退化图像复原;最后,对复原效果进行相应比较,结果表明在强湍流条件下本算法具有更为理想的复原效果。该研究可为复杂水流条件下水下退化图像复原方法研究提供参考。%Eestimating their weight and size, therefore valuing their growing steps, based on snapped their photographs, is an efficient and quick method in order to meet the information requirment for process controlling in industrial aquaculture. For this purpose, effective restoring methods to process underwater degraded images are essential for this technology. Based on polarization imaging technology and improved turbulence model, a robust model for underwater degraded images restoration was proposed in this paper. Firstly, aimed at increasing the completeness of prior knowledge required by restoring degraded images method, an improved underwater turbulence model was designed by considering the wave structure function and distribution function of scattering scale parameter to overcome the shortcoming resulting from the simplified turbulence model, which simply imitated the situation for atmospheric turbulence and graded turbulence intensity only depending on fuzzy factor. Secondly, noise characteristics in degraded images was drawn from comparison between“and“,“minus”images, which were computed from polarization images, based on polarization characteristics of underwater forward scattering light

  13. The Primal-dual Algorithm based on Tikhonov Model Application in Image Restoration%基于 Tikhonov 模型的原-对偶算法在图像恢复中的应用

    Institute of Scientific and Technical Information of China (English)

    何姣姣; 庹谦; 周震; 陈剑鸣

    2016-01-01

    图像在采集、存储、传输以及显示过程中,由于各种因素,往往会造成图像模糊,所以消除图像中的噪声、去除模糊等意义重大。在模糊图像恢复过程中,运用针对 Tikhonov 正则化问题演化来的梯度下降法与原-对偶算法,以及它们改进的算法对模糊图像进行恢复。在这一模型中,正则化参数的选择对图像恢复的效果有很大的影响,选取一个相对合适的正则化参数来平衡拟合项与正则项情况很重要。选定合适的正则化参数后,在 Armijo 准则下应用0.618优选法选择步长,进行梯度下降法以及正则化下的原-对偶算法的计算,对模糊灰度图像进行恢复。使用上述2种方法对模糊图像进行恢复,实验表明,与梯度下降法相较而言,原-对偶算法在图像恢复中效果更好。%In the process of collection,storage,transmission and display of image,it often has blurring due to various factors,so to eliminate the noise in the image and remove the fuzzy is of great significance.In the process of blur image res-toration,the gradient decent method with the primal-dual algorithm and improved algorithm evolved by Tikhonov regulariza-tion problem are used to recover the image.In this model,the choice of regularization parameter has a great influence on the effect of image restoration,and it is very important to select a relatively suitable regularization parameter to balance the fit-ting term and regularization term.After selecting the appropriate regularization parameter,the gradient descent method and the primal dual algorithm are applied in the Armijo criteria,and the fuzzy gray image is restored by using the gradient de-scent method and the normalized algorithm.Two methods are used to restore the blurred image.The experiments show that the original dual algorithm is better than the gradient descent method in image restoration.

  14. Accelerated gradient methods for total-variation-based CT image reconstruction

    CERN Document Server

    Jørgensen, Jakob Heide; Hansen, Per Christian; Jensen, Søren Holdt; Sidky, Emil Y; Pan, Xiaochuan

    2011-01-01

    Total-variation (TV)-based Computed Tomography (CT) image reconstruction has shown experimentally to be capable of producing accurate reconstructions from sparse-view data. In particular TV-based reconstruction is very well suited for images with piecewise nearly constant regions. Computationally, however, TV-based reconstruction is much more demanding, especially for 3D imaging, and the reconstruction from clinical data sets is far from being close to real-time. This is undesirable from a clinical perspective, and thus there is an incentive to accelerate the solution of the underlying optimization problem. The TV reconstruction can in principle be found by any optimization method, but in practice the large-scale systems arising in CT image reconstruction preclude the use of memory-demanding methods such as Newton's method. The simple gradient method has much lower memory requirements, but exhibits slow convergence. In the present work we consider the use of two accelerated gradient-based methods, GPBB and UP...

  15. Restorative dentistry for children.

    Science.gov (United States)

    Donly, Kevin J

    2013-01-01

    This article discusses contemporary pediatric restorative dentistry. Indications and contraindications for the choice of different restorative materials in different clinical situations, including the risk assessment of the patient, are presented. The specific use of glass ionomer cement or resin-modified glass ionomer cement, resin-based composite, and stainless steel crowns is discussed so that preparation design and restoration placement is understood.

  16. Global Ecosystem Restoration Index

    DEFF Research Database (Denmark)

    Fernandez, Miguel; Garcia, Monica; Fernandez, Nestor

    2015-01-01

    The Global ecosystem restoration index (GERI) is a composite index that integrates structural and functional aspects of the ecosystem restoration process. These elements are evaluated through a window that looks into a baseline for degraded ecosystems with the objective to assess restoration...

  17. Linking restoration ecology with coastal dune restoration

    Science.gov (United States)

    Lithgow, D.; Martínez, M. L.; Gallego-Fernández, J. B.; Hesp, P. A.; Flores, P.; Gachuz, S.; Rodríguez-Revelo, N.; Jiménez-Orocio, O.; Mendoza-González, G.; Álvarez-Molina, L. L.

    2013-10-01

    Restoration and preservation of coastal dunes is urgently needed because of the increasingly rapid loss and degradation of these ecosystems because of many human activities. These activities alter natural processes and coastal dynamics, eliminate topographic variability, fragment, degrade or eliminate habitats, reduce diversity and threaten endemic species. The actions of coastal dune restoration that are already taking place span contrasting activities that range from revegetating and stabilizing the mobile substrate, to removing plant cover and increasing substrate mobility. Our goal was to review how the relative progress of the actions of coastal dune restoration has been assessed, according to the ecosystem attributes outlined by the Society of Ecological Restoration: namely, integrity, health and sustainability and that are derived from the ecological theory of succession. We reviewed the peer reviewed literature published since 1988 that is listed in the ISI Web of Science journals as well as additional references, such as key books. We exclusively focused on large coastal dune systems (such as transgressive and parabolic dunefields) located on natural or seminatural coasts. We found 150 articles that included "coastal dune", "restoration" and "revegetation" in areas such as title, keywords and abstract. From these, 67 dealt specifically with coastal dune restoration. Most of the studies were performed in the USA, The Netherlands and South Africa, during the last two decades. Restoration success has been assessed directly and indirectly by measuring one or a few ecosystem variables. Some ecosystem attributes have been monitored more frequently (ecosystem integrity) than others (ecosystem health and sustainability). Finally, it is important to consider that ecological succession is a desirable approach in restoration actions. Natural dynamics and disturbances should be considered as part of the restored system, to improve ecosystem integrity, health and

  18. A Novel Approach of High-dimensional Image Restoration Based on Geometry Algebra%基于几何代数的散焦模糊高维图像恢复

    Institute of Scientific and Technical Information of China (English)

    户利利

    2012-01-01

    The geometry algebra can compute and analyze the high-dimensional space geometry in an easy way. Taking advantage of this property, the paper denotes the color image as one point in the geometry space by using the geometry algebra. The image transform can be treated on the language of geometry algebra as action of some transform. The image transform can be treated as the movements of the point in the high-dimensional space from the view of geometry. Beginning with the original blurred image, two further blurred images are got, then the restoral image can be obtained through the regressive curve derived from the three points in the geometry space which are mapped from the images by making use of geometry algebra. Experiments are presented to prove the availability of this method.%几何代数易于对高维空间几何进行计算和分析,应用几何代数的这一特性,将彩色图像表示为高维几何空间中的点元素,利用几何代数描述图像的变换关系,将图像的散焦变换看作是高维空间中点元素的平移运动.通过分析模糊图像以及其衍生出的相关模糊图像对应在高维几何空间中点之间的分布关系的研究,计算出空间中复原图像的点分布位置.实验结果验证了该方法的有效性.

  19. Core spatial position restoring of WFSD-1 borehole with borehole imaging logging data%汶川地震断裂带科学钻探WFSD-1孔成像测井岩心空间归位

    Institute of Scientific and Technical Information of China (English)

    聂昕; 邹长春; 肖昆; 徐晋; 牛一雄; 孔广胜

    2012-01-01

    After the Wenchuan earthquake in 2008, the government of our country rapidly implemented the Wenchuan Earthquake Fault Zone Scientific Drilling Project (WFSD). Form drilling cores can obtain the direct data of the underground. This is very important for scientific drilling researches. But the original depths and orientations of cores cannot be positive, so core spatial position restoring is needed. By being processed by imaging log-core scanning picture processing integrated software (CCSDLogCore), the spatial positions of 2055 pieces of core scanning images collected from No. 1 borehole of Wenchuan Earthquake Fault Zone Scientific Drilling (WFSD-1) are restored precisely and visually. By analyzing the results of the restoring work, it is found that the depth error of the cores increased with the depth of the hole, and that confirmed the results accord the reality. These results lay a good foundation for the following geological structure analysis; the problems during the work are summed up and suggestions are presented as follows:it' s better to do the acoustic imaging logging and the resistivity imaging logging at the same hole so that we can obtain better information about the wall of the borehole; we should also avoid the problems caused by human during the preliminary work of position restoring before we can start the accurate and efficient work of core position restoring.%2008年汶川大地震发生后,我国迅速实施了汶川地震断裂带科学钻探项目(WFSD).钻井取心是研究地下情况的直接资料,但取心时通常采用非定向取心技术,缺少准确的深度和方位信息,需要利用测井资料对其进行深度和方向的还原,即岩心空间归位.针对汶川地震断裂带科学钻探项目一号孔(WFSD-1孔),利用成像-岩心扫描图像综合处理软件(CCSDLogCore)精确和直观的完成了2055块岩心图像的空间归位.对归位成果进行了分析,发现随着钻孔深度的增加,岩心深度误差增大,说

  20. 噪声扰动下低光照蚕蛹图像恢复算法与试验%Algorithm and experiments of noisy low-illumination silkworm pupa images restoration

    Institute of Scientific and Technical Information of China (English)

    陶丹; 李光林; 王峥荣; 邱光应

    2015-01-01

    In the machine vision-based intelligent system for recognizing and sorting male or female silkworm pupa, the quality of silkworm pupa images is the key for accurate recognition. Low illumination and noise,as the main factors degrading silkworm pupa images, can give rise to the loss of images textures and structures to a great extent, which brings a challenge for intelligent system to identify silkworm pupa’s gender. State-of-the-art methods, like Shan’s work, can be ineffective when images are perturbed by noise. The main contribution of our work was the effective elimination of noise by Tikhonov regularization while restoring image contrast and preserving image textures and structures based on the Shan’s modeling. In order to improve the quality of degraded silkworm pupa images, a novel method combining tone mapping with Tikhonov regularization, which was capable of enhancing image contrast and compressing noise simultaneously, was proposed in this paper. According to Shan’s work, it was assumed that Low-illumination image is obtained via dynamically compressing a Low-illumination image. A 3×3 neighborhood of pixels in both images was defined. The linear functions mapping locally radiance in such a 3×3 window of low-illumination silkworm pupa images to that of the desired ones were formulated. The monotonicity of linear functions can preserve local structural information of image. Through integrating these linear functions, the image-level objective function was established to restore image illumination contrast. Further, Tikhonov regularization implemented by the Laplace of Gaussian (LoG) operator was used to obtain the final objective function. Tikhonov regularization could not only smooth noise and preserve structural information of image effectively but also could be beneficial to a stable solution in the iterative processes. The existence and unique of solution of the objective function was addressed via verification of convexity according to D. P

  1. Restoring the incisal edge.

    Science.gov (United States)

    Terry, Douglas A

    2005-01-01

    Restorative dentistry evolves with each development of new material and innovative technique. Selection of improved restorative materials that simulate the physical properties and other characteristics of natural teeth, in combination with restorative techniques such as the proximal adaptation and incremental layering, provide the framework that ensures the optimal development of an esthetic restoration. These advanced placement techniques offer benefits such as enhanced chromatic integration, polychromatism, ideal anatomical form and function, optimal proximal contact, improved marginal integrity and longer lasting directly placed composite restorations. The purpose of this article is to give the reader a better understanding of the complex restorative challenge in achieving true harmonization of the primary parameters in esthetics (that is, color, shape and texture) represented by the replacement of a single anterior tooth. The case presented demonstrates the restoration of a Class IV fracture integrating basic adhesive principles with these placement techniques and a recently developed nanoparticle hybrid composite resin system (Premise, Kerr/Sybron, Orange, CA). The clinical presentation describes preoperative considerations, tooth preparation, development of the body layer, internal characterization with tints, development of the artificial enamel layer, shaping and contouring, and polishing of a Class IV composite restoration. The clinical significance is that anterior tooth fractures can be predictably restored using contemporary small particle hybrid composite resin systems with the aforementioned restorative techniques. These placement techniques when used with proper attention to preparation design, adhesive protocol and finishing and polishing procedures, allow the clinician to successfully restore form, function and esthetics to the single anterior tooth replacement.

  2. Enhancement Algorithm for the Restoration of Dust Image Based on Dark-Channel Prior%基于暗原色先验的沙尘天气图像恢复算法研究

    Institute of Scientific and Technical Information of China (English)

    李海燕; 钟梦之

    2016-01-01

    Concerning the problem that image captured from dust weather has low contrast and details, based on the McCarney physical model and dark-channel piror theory ,an enhancement algorithm for the restoration of single dust image was proposed.The clear image could be recovered quickly.The experimental results show that the method can improve the quality and enhance the detail of the degraded image.%针对沙尘天气下图像质量下降的情况,在McCarney大气模型上,利用暗原色先验的规律和图像增强方法,提出一种快速、有效的单一图像恢复算法,并进行了仿真。实验结果表明,该算法能有效地恢复沙尘天气图像的清晰度,增强图像细节呈现。

  3. Restoring the worn dentition.

    Science.gov (United States)

    Ibsen, R L; Ouellet, D F

    1992-01-01

    Strong dental materials and dental porcelains are providing dentists with restorative opportunities that are more conservative because they require less destruction of healthy tooth structure and yield a more esthetic result. In cases of severe wear due to attrition, abrasion, and erosion, this process can be stopped, restoring the esthetics and function by using proper techniques and materials. The case report described in this article demonstrates the conservative restoration of severe wear due to attrition and erosion. Teeth were lengthened, wear was restored, and further wear was ceased by using a combination of bonded porcelain, a heat, light, and self-cure resin system, and a new glass-ionomer restorative material. The result was a strong, durable restoration (that required no anesthesia) with high esthetics.

  4. Watershed Restoration Project

    Energy Technology Data Exchange (ETDEWEB)

    Julie Thompson; Betsy Macfarlan

    2007-09-27

    In 2003, the U.S. Department of Energy issued the Eastern Nevada Landscape Coalition (ENLC) funding to implement ecological restoration in Gleason Creek and Smith Valley Watersheds. This project was made possible by congressionally directed funding that was provided through the US Department of Energy, Energy Efficiency and Renewable Energy, Office of the Biomass Program. The Ely District Bureau of Land Management (Ely BLM) manages these watersheds and considers them priority areas within the Ely BLM district. These three entities collaborated to address the issues and concerns of Gleason Creek and Smith Valley and prepared a restoration plan to improve the watersheds’ ecological health and resiliency. The restoration process began with watershed-scale vegetation assessments and state and transition models to focus on restoration sites. Design and implementation of restoration treatments ensued and were completed in January 2007. This report describes the restoration process ENLC undertook from planning to implementation of two watersheds in semi-arid Eastern Nevada.

  5. Kinect scanning plant depth image restoration based onK-means and K-nearest neighbor algorithms%基于K-means和近邻回归算法的Kinect植株深度图像修复

    Institute of Scientific and Technical Information of China (English)

    沈跃; 徐慧; 刘慧; 李宁

    2016-01-01

    针对Kinect传感器应用于农业植株检测产生的图像噪声问题,特别是由光线以及传感器自身局限导致的匹配图像目标植株数据的缺失,提出一种基于K-means和近邻回归算法的植株深度检测图像修复方法。首先对Kinect传感器获取的彩色RGB图像进行阈值分割预处理提取植株目标区域,再利用K-means聚类算法去除背景噪声,使得植株目标区域轮廓更加清晰;然后基于配准的彩色图像和深度图像,对获取的深度图像中可疑像素点的深度数据采取近邻回归算法进行修复,再将修复后的深度图像与目标分割后的彩色图像进行植株区域的匹配,并进行二次近邻回归算法修正错误的深度数据,最后获取目标植株深度信息的检测图像。试验结果证明,采用RGB阈值分割和K-means聚类算法植株目标区域分割误差均值为12.33%,比单一RGB阈值分割和K-means聚类分割误差降低了12.12和41.48个百分点;同时结合聚类后的彩色图像对深度数据进行两次近邻回归算法修复深度数据,能够提高深度数据边缘的清晰度,单帧深度数据空洞点进行修复数据的准确度提高。该研究结果可为农业植株检测、植株三维重构、精准对靶喷雾等提供参考。%The Kinect sensor scanning images for agricultural plants are vulnerable to field light conditions and background noise, etc. In addition, the amount of data of the color image and depth image affect the efficiency and accuracy of the plant area, which leads to the difficulty of meeting the requirement for the Kinect sensor in agricultural plant detection. For the above problems, considering the influence of the light conditions and complex background information in agricultural environment on the quality of the plant detection and the depth data acquisition, in this paper, we proposed a plant depth detection image restoration method based onK-means and

  6. Projection-Based Image Restoration via Sparse Representation and Nonlocal Regularization%基于投影的稀疏表示与非局部正则化图像复原方法

    Institute of Scientific and Technical Information of China (English)

    2014-01-01

    提出一种基于投影的稀疏表示与非局部正则化相结合的图像去模糊、去噪图像复原方法。该方法结合了自适应构造字典的稀疏表示与非局部总变差,提出的正则化模型分解为三个投影子问题进行求解以提高求解效率。实验结果表明,本文所提出的图像复原方法能够有效地保持原图像的纹理细节信息,对于不同程度的退化图像上均有较好的复原结果,在视觉效果和客观评价指标上均优于相比较的现有方法。%This paper proposes a projection based sparse representation and nonlocal regularization deblurring and denoising image restoration algorithm .The algorithm combines sparse representation via adaptive learned dictionary and nonlocal total varia -tion ,and the proposed regularization model is divided into three projection sub problems to solve to improve the efficiency .Experi-mental results show that the proposed algorithm can preserve the detail information effectively ,and have nice restoration results for images with different degree of degradation .The proposed algorithm achieves improvement on both visual appearance and objective indices compared with state-of-the-art methods .

  7. Images

    Data.gov (United States)

    National Aeronautics and Space Administration — Images for the website main pages and all configurations. The upload and access points for the other images are: Website Template RSW images BSCW Images HIRENASD...

  8. The Hip Restoration Algorithm

    Science.gov (United States)

    Stubbs, Allston Julius; Atilla, Halis Atil

    2016-01-01

    Summary Background Despite the rapid advancement of imaging and arthroscopic techniques about the hip joint, missed diagnoses are still common. As a deep joint and compared to the shoulder and knee joints, localization of hip symptoms is difficult. Hip pathology is not easily isolated and is often related to intra and extra-articular abnormalities. In light of these diagnostic challenges, we recommend an algorithmic approach to effectively diagnoses and treat hip pain. Methods In this review, hip pain is evaluated from diagnosis to treatment in a clear decision model. First we discuss emergency hip situations followed by the differentiation of intra and extra-articular causes of the hip pain. We differentiate the intra-articular hip as arthritic and non-arthritic and extra-articular pain as surrounding or remote tissue generated. Further, extra-articular hip pain is evaluated according to pain location. Finally we summarize the surgical treatment approach with an algorithmic diagram. Conclusion Diagnosis of hip pathology is difficult because the etiologies of pain may be various. An algorithmic approach to hip restoration from diagnosis to rehabilitation is crucial to successfully identify and manage hip pathologies. Level of evidence: V. PMID:28066734

  9. 基于波前探测的视网膜图像半盲解卷积复原%Retinal Image Semi-Blind Deconvolution Restoration Based on Wave-Front Detection

    Institute of Scientific and Technical Information of China (English)

    钮赛赛; 沈建新; 梁春; 张运海

    2012-01-01

    获取高分辨视网膜图像的难点在于是否能够消除成像系统中像差的影响.为了进一步改善图像质量、提高视网膜细胞组织的观察分辨率,提出了结舍自适应光学成像技术和视网膜图像后处理算法的方法.通过视网膜成像系统中的自适应光学技术实时校正人眼像差并获取初始视网膜图像,根据成像系统中的残余像差重建光学传递函数作为图像复原模型初始参数估计,最后对视网膜图像进行条件约束迭代半盲解卷积复原,进一步消除像差对成像质量的影响,从而得到高分辨率视网膜图像.实验结果表明:由这种方法处理的视网膜图像质量能得到明显提高,其图像质量客观评价参数(GMG,LS和PSV)比原始图像提高近1倍,在视网膜细胞的空间频率范围内(70~90 cyc/deg),复原后图像的功率谱平均值比原始图像提高了10倍左右,基本能满足观察分辨率要求.%The difficulty to obtain high resolution retinal image lies in eliminating the effect of aberration which exists in the imaging system. The proposed combination of adaptive optics imaging technology and retinal image post processing algorithm can improve image quality and observation resolution. The aberration of the human eye can be corrected in real time by adaptive optics technology in retinal imaging system and the original retinal image can be obtained, and the optical transfer function which is used as initial parameter estimate of image deconvolution modal can be constructed with the residual aberration of the imaging system. Finally, iterative semi-blind constraint deconvolution restoration is carried out on the retinal image, so as to eliminate the influence of residual aberration on imaging quality and obtain the high resolution retinal images. The experimental results show that the retinal image quality is improved significantly by the proposed method, the image quality objective evaluation parameters(GMG, LS

  10. Toponymic Restoration in Irkutsk

    Directory of Open Access Journals (Sweden)

    Alexander Snarsky

    2016-10-01

    Full Text Available The article analyzes the discussion on restoration of historical names of public spaces in Irkutsk. It also reviews different approaches to the problem that appeared in the historical science and publicism. The author says about the necessity of a strictly historical approach to the toponymic restoration.

  11. Guiding Restoration Principles

    Science.gov (United States)

    2004-12-01

    restoration of important ecosystem functions requires reintegrating landscapes or restorating the func- tional aspects of landscapes ( Risser 1992...51-64. Risser , P. G. 1992. Landscape ecology approach to ecosystem rehabilitation. Pages 37-46 in M. L. Wali (ed.), Ecosystem Rehabilitation

  12. Research on color restoration of color image display%彩色图像显示系统的色彩还原技术研究

    Institute of Scientific and Technical Information of China (English)

    王欢; 陈向宁; 姜明勇

    2014-01-01

    图像从输入设备到显示器观察,再到输出设备或最终的图像文件的流程中,由于不同设备的呈色机理、呈色特性、所采用的呈色空间不同,造成颜色信息在不同的设备间传递时出现了偏差,要维护原始的色彩是非常困难的。借助PCS空间,通过多项式分区回归的方法进行色彩空间转换。实验结果表明,这种方法能够实现彩色图像显示系统的色彩还原且精度较高。%In the course of image processing, an image enters the input device, experiences observation in the monitor, and arrives at the output device or the final image file. In this process, due to the different coloring mechanism, colorimetric characteristics and colorimetric space of different devices, there occurs color distortion when color information passes between different devices, so it is rather difficult to maintain the original color. With the PCS space, this paper converts color spaces by the method of polynomial zone regression. The result shows that this method can achieve color reproduc-tion for color image display system with high precision.

  13. Mammograms restoration by using Wiener filter

    Energy Technology Data Exchange (ETDEWEB)

    Dakovic, M., E-mail: mdakovic@gmail.com; Mijovic, S. [University of Montenegro, Faculty of Natural Sciences and Mathematics, Dž. Vašingtona bb, 20000 Podgorica (Montenegro); Ivanović, S. [Clinical Center of Montenegro, 20000 Podgorica (Montenegro)

    2016-03-25

    Restoration of digital mammograms, as a pre-processing tool, using deconvolution procedures, is analysed. It implies, knowing Modulation Transfer Function (MTF) of the mammography device and the estimation of the mammogram’s noise. Wiener filter is used, as the most objective in mammograms restoration by deconvolution. Using MATLAB program the deconvolution procedures are conducted in two ways with different level of approximation. The first method approximates the noise/signal power ratio by a constant and the second method uses autocorrelation functions of the noise and signals. Abilities and limitations of the methods are analysed and checked by using the raw images of the bar-pattern due to better visualisation of the obtained results. The raw images are obtained at a Computed Radiography (CR) mammography device in Clinical Centre in Podgorica. It is found that quality of the restored image highly depends of knowledge of type and magnitude of noise. In the both methods spatial resolution of the restored images are improved, but much better in a case where autocorrelation functions of the noise and signal are used. This procedure is proposed as an objective pre-processing tool to put back imperfectness of mammography devices.

  14. ABOUT THE DIGITAL RESTORATION OF HISTORICAL TEXT DOCUMENTS

    Directory of Open Access Journals (Sweden)

    V. V. Starovoitov

    2015-01-01

    Full Text Available The main problems of old text document restoration and approaches to their solution during restoration of images of these documents by methods of information technology are considered. Primary source documents are not changed, but their digital copies can be modified with orientation on different applications and according to the different levels of processing

  15. Novel Single Hazy Image Restoration Method Based on Nonlocal Total Variation Regularization Optimization%基于非局部全变分正则化优化的单幅雾天图像恢复新方法

    Institute of Scientific and Technical Information of China (English)

    何人杰; 樊养余; WANG Zhiyong; FENG David

    2016-01-01

    Based on the property that the scene radiance is of high contrast and the atmospheric veil is locally smooth, a novel single hazy image restoration method based on nonlocal total variation regularization optimization is proposed in this paper. In order to obtain the atmospheric veil of a hazy image, a constrained nonlocal total variation regularization is firstly applied. Then, the accurate atmospheric veil is estimated using a nonlocal Rudin- Osher-Fatemi model, which is solved by a modified split Bregman method. Experimental results demonstrate that the proposed approach is capable of recovering the scene radiance from a single hazy image effectively, especially for the regions with multi-texture.%该文针对无雾图像具有高灰度对比度且大气遮罩局部平滑的特性,提出一种基于非局部全变分正则化优化的单幅雾天图像恢复新方法。先构建一种基于非局部全变分正则化的有约束优化算法对大气遮罩进行估计,然后通过优化Bregman分离迭代法求解非局部Rudin-Osher-Fatemi模型获得准确的大气遮罩,进而从雾天场景图像恢复出场景图像。实验结果表明,所提新方法可以有效地对雾天降质图像进行复原,对多纹理复杂区域的恢复效果也较好。

  16. Fourier-wavelet restoration in PET/CT brain studies

    Energy Technology Data Exchange (ETDEWEB)

    Knesaurek, Karin, E-mail: karin.knesaurek@mssm.edu [Division of Nuclear Medicine, The Mount Sinai Medical Center, One Gustave L. Levy Place, New York, NY 10029 (United States)

    2012-10-11

    Our goal is to improve brain PET imaging through the application of a novel, hybrid Fourier-wavelet (WFT) restoration technique. The major limitation of PET studies is a relatively poor resolution in comparison with MRI and CT imaging and there is a need for improved PET imaging. A GE DLS PET/CT 16 slice system was used to acquire the studies. In order to create restoration filters the point source study was performed. The 6-fillable spheres and 3D Hoffman brain phantom studies were acquired and used to test and optimize the restoration approach. The patient data used in the study were acquired in a 3D PET mode, using the standard clinical protocol. Here, we have implemented Fourier-wavelet regularized restoration. In the Fourier domain, the inverse of modulation transfer function was multiplied by a Butterworth low-pass filter, order n=6 and cut-off frequency f=0.35 cycles/pixel. In addition, wavelet (Daubechies, order 2) noise suppression was applied by 'hard threshold'. Hot spheres and 3D Hoffman brain studies showed that the restoration process not only improves resolution and contrast but also improves quantification in 3D PET/CT imaging. The average contrast increase was 19% and the quantification improved in the range 8-20% depending on sphere size. In the restored images, there was no significant increase in noise when compared with the original images. The clinical studies followed brain phantom findings, i.e., the restored images had better contrast and resolution properties, when compared with the original images. The results of the study demonstrate that the quality and quantification of 3D brain {sup 18}F FDG PET images can be significantly improved by Fourier-wavelet (WFT) restoration filtering.

  17. Fourier-wavelet restoration in PET/CT brain studies

    Science.gov (United States)

    Knešaurek, Karin

    2012-10-01

    Our goal is to improve brain PET imaging through the application of a novel, hybrid Fourier-wavelet (WFT) restoration technique. The major limitation of PET studies is a relatively poor resolution in comparison with MRI and CT imaging and there is a need for improved PET imaging. A GE DLS PET/CT 16 slice system was used to acquire the studies. In order to create restoration filters the point source study was performed. The 6-fillable spheres and 3D Hoffman brain phantom studies were acquired and used to test and optimize the restoration approach. The patient data used in the study were acquired in a 3D PET mode, using the standard clinical protocol. Here, we have implemented Fourier-wavelet regularized restoration. In the Fourier domain, the inverse of modulation transfer function was multiplied by a Butterworth low-pass filter, order n=6 and cut-off frequency f=0.35 cycles/pixel. In addition, wavelet (Daubechies, order 2) noise suppression was applied by “hard threshold”. Hot spheres and 3D Hoffman brain studies showed that the restoration process not only improves resolution and contrast but also improves quantification in 3D PET/CT imaging. The average contrast increase was 19% and the quantification improved in the range 8-20% depending on sphere size. In the restored images, there was no significant increase in noise when compared with the original images. The clinical studies followed brain phantom findings, i.e., the restored images had better contrast and resolution properties, when compared with the original images. The results of the study demonstrate that the quality and quantification of 3D brain 18F FDG PET images can be significantly improved by Fourier-wavelet (WFT) restoration filtering.

  18. Challenges of ecological restoration

    DEFF Research Database (Denmark)

    Halme, Panu; Allen, Katherine A.; Aunins, Ainars

    2013-01-01

    on Biological Diversity. Several northern countries are now taking up this challenge by restoring forest biodiversity with increasing intensity. The ecology and biodiversity of boreal forests are relatively well understood making them a good model for restoration activities in many other forest ecosystems. Here......The alarming rate of ecosystem degradation has raised the need for ecological restoration throughout different biomes and continents. North European forests may appear as one of the least vulnerable ecosystems from a global perspective, since forest cover is not rapidly decreasing and many...... ecosystem services remain at high level. However, extensive areas of northern forests are heavily exploited and have lost a major part of their biodiversity value. There is a strong requirement to restore these areas towards a more natural condition in order to meet the targets of the Convention...

  19. Restoration of ailing wetlands.

    Directory of Open Access Journals (Sweden)

    Oswald J Schmitz

    2012-01-01

    Full Text Available It is widely held that humankind's destructive tendencies when exploiting natural resources leads to irreparable harm to the environment. Yet, this thinking runs counter to evidence that many ecological systems damaged by severe natural environmental disturbances (e.g., hurricanes can restore themselves via processes of natural recovery. The emerging field of restoration ecology is capitalizing on the natural restorative tendencies of ecological systems to build a science of repairing the harm inflicted by humans on natural environment. Evidence for this, for example, comes from a new meta-analysis of 124 studies that synthesizes recovery of impacted wetlands worldwide. While it may take up to two human generations to see full recovery, there is promise, given human will, to restore many damaged wetlands worldwide.

  20. Science of landscape restoration

    CSIR Research Space (South Africa)

    De Wet, Benita

    2011-11-01

    Full Text Available Over the last two decades the ecological restoration of industrial land has developed into a specialist science combined with highly sophisticated management activities. A prime example of this approach is a unique partnership between the CSIR...

  1. Restoring susceptibility induced MRI signal loss in rat brain at 9.4 T: A step towards whole brain functional connectivity imaging.

    Directory of Open Access Journals (Sweden)

    Rupeng Li

    Full Text Available The aural cavity magnetic susceptibility artifact leads to significant echo planar imaging (EPI signal dropout in rat deep brain that limits acquisition of functional connectivity fcMRI data. In this study, we provide a method that recovers much of the EPI signal in deep brain. Needle puncture introduction of a liquid-phase fluorocarbon into the middle ear allows acquisition of rat fcMRI data without signal dropout. We demonstrate that with seeds chosen from previously unavailable areas, including the amygdala and the insular cortex, we are able to acquire large scale networks, including the limbic system. This tool allows EPI-based neuroscience and pharmaceutical research in rat brain using fcMRI that was previously not feasible.

  2. Millimeter wave image restoration based on fuzzy radial basis function neural networks and sparse representation%基于模糊径向基神经网络和稀疏表示的毫米波图像恢复

    Institute of Scientific and Technical Information of China (English)

    尚丽; 苏品刚; 陈杰

    2012-01-01

    As to the problems that Millimeter Wave ( MMW) image is contaminated by much unknown noise and has lower resolution, and considering the non-linear filter property of Fuzzy Radial Basis Function Neural Network ( F-RBFNN) and the self-adaptive denoising property of Sparse Representation (SR) based on K-Singular Value Decomposition (K-SVD), a MMW restoration method was proposed by combining F-RBFNN and sparse representation. In F-RBFNN, the knowledge expression of fuzzy logic and the reasoning ability were combined with the RBFNN's capabilities of fast learning and generalization. In order to realize the non-linear filtering to the MMW image, F-RBFNN's structure and parameters were adjusted according to the real problem. Furthermore, utilizing the advantages of sparse representation method, which the sparse representation behaves the visual characteristic and can denoise effectively when maintaining features of the object, the training results of F-RBFNN were locally denoised once again, and the MMW image with high resolution was obtained. Using the Relative Single Noise Ratio (RSNR) criterion to measure the quality of denoised images, the simulation results show that, compared with other denoising methods such as F-RBFNN, K-SVD denoising, and wavelet denoising, the proposed method combining F-RBFNN and SR can better restore the quality of MMW image.%针对毫米波(MMW)图像包含大量未知噪声、图像分辨率较低的问题,考虑模糊径向基函数神经网络(F-RBFNN)的非线性滤波特性和基于K-奇异值分解(K-SVD)稀疏表示(SR)的自适应消噪特性,提出了一种级联消噪的毫米波图像恢复方法.F-RBFNN将模糊逻辑的知识表达和推理能力与RBFNN的快速学习能力和泛化能力结合起来,可根据实际问题调整网络结构参数,对MMW图像达到非线性滤波的目的.进一步利用K-SVD稀疏表示具有人眼视觉特性,在保持目标特征的同时可有效消噪的优点,对FRBFNN的训练结果再

  3. Restoring primary anterior teeth.

    Science.gov (United States)

    Waggoner, William F

    2002-01-01

    A variety of esthetic restorative materials are available for restoring primary incisors. Knowledge of the specific strengths, weakness, and properties of each material will enhance the clinician's ability to make the best choice of selection for each individual situation. Intracoronal restorations of primary teeth may utilize resin composites, glass ionomer cements, resin-modified ionomers, or polyacid-modified resins. Each has distinct advantages and disadvantages and the clinical conditions of placement may be a strong determining factor as to which material is utilized. Full coronal restoration of primary incisors may be indicated for a number of reasons. Crowns available for restoration of primary incisors include those that are directly bonded onto the tooth, which generally are a resin material, and those crowns that are luted onto the tooth and are some type of stainless steel crown. However, due to lack of supporting clinical data, none of the crowns can be said to be superior to the others under all circumstances. Though caries in the mandibular region is rare, restorative solutions for mandibular incisors are needed. Neither stainless steel crowns nor celluloid crown forms are made specifically for mandibular incisors. Many options exist to repair carious primary incisors, but there is insufficient controlled, clinical data to suggest that one type of restoration is superior to another. This does not discount the fact that dentists have been using many of these crowns for years with much success. Operator preferences, esthetic demands by parents, the child's behavior, and moisture and hemorrhage control are all variables which affect the decision and ultimate outcome of whatever restorative treatment is chosen.

  4. Restoration in South Africa

    CSIR Research Space (South Africa)

    Blignaut, J

    2010-01-01

    Full Text Available is restoration? Our human population continues to grow at an unprecedented rate, demanding ever-increasing amounts of goods and services from the natural ecosystems upon which we depend. No part of the planet has been left untouched, and many areas.... Another selection criterion was the need for historic data and a restoration history. In each of the cases the ASSET Research team collaborates with partners, that include the Working for Water programme, Flower Valley, the Ostrich Business Chamber...

  5. Iterative restoration algorithms for nonlinear constraint computing

    Science.gov (United States)

    Szu, Harold

    A general iterative-restoration principle is introduced to facilitate the implementation of nonlinear optical processors. The von Neumann convergence theorem is generalized to include nonorthogonal subspaces which can be reduced to a special orthogonal projection operator by applying an orthogonality condition. This principle is shown to permit derivation of the Jacobi algorithm, the recursive principle, the van Cittert (1931) deconvolution method, the iteration schemes of Gerchberg (1974) and Papoulis (1975), and iteration schemes using two Fourier conjugate domains (e.g., Fienup, 1981). Applications to restoring the image of a double star and division by hard and soft zeros are discussed, and sample results are presented graphically.

  6. Ecosystem Restoration: A Manager's Perspective

    Science.gov (United States)

    James G. Kenna; Gilpin R., Jr. Robinson; Bill Pell; Michael A. Thompson; Joe McNeel

    1999-01-01

    Elements of ecological restoration underlie much of what we think of as ecosystem management, and restoration projects on federal lands represent some of the most exciting, challenging, and convincing demonstrations of applied ecosystem management. The Society for Ecological Restoration defined restoration as "the process of reestablishing to the extent possible...

  7. Suppression of the PI3K pathway in vivo reduces cystitis-induced bladder hypertrophy and restores bladder capacity examined by magnetic resonance imaging.

    Science.gov (United States)

    Qiao, Zhongwei; Xia, Chunmei; Shen, Shanwei; Corwin, Frank D; Liu, Miao; Guan, Ruijuan; Grider, John R; Qiao, Li-Ya

    2014-01-01

    This study utilized magnetic resonance imaging (MRI) to monitor the real-time status of the urinary bladder in normal and diseased states following cyclophosphamide (CYP)-induced cystitis, and also examined the role of the phosphoinositide 3-kinase (PI3K) pathway in the regulation of urinary bladder hypertrophy in vivo. Our results showed that under MRI visualization the urinary bladder wall was significantly thickened at 8 h and 48 h post CYP injection. The intravesical volume of the urinary bladder was also markedly reduced. Treatment of the cystitis animals with a specific PI3K inhibitor LY294002 reduced cystitis-induced bladder wall thickening and enlarged the intravesical volumes. To confirm the MRI results, we performed H&E stain postmortem and examined the levels of type I collagen by real-time PCR and western blot. Inhibition of the PI3K in vivo reduced the levels of type I collagen mRNA and protein in the urinary bladder ultimately attenuating cystitis-induced bladder hypertrophy. The bladder mass calculated according to MRI data was consistent to the bladder weight measured ex vivo under each drug treatment. MRI results also showed that the urinary bladder from animals with cystitis demonstrated high magnetic signal intensity indicating considerable inflammation of the urinary bladder when compared to normal animals. This was confirmed by examination of the pro-inflammatory factors showing that interleukin (IL)-1α, IL-6 and tumor necrosis factor (TNF)α levels in the urinary bladder were increased with cystitis. Our results suggest that MRI can be a useful technique in tracing bladder anatomy and examining bladder hypertrophy in vivo during disease development and the PI3K pathway has a critical role in regulating bladder hypertrophy during cystitis.

  8. Historical Restoration of the Patriotic Image of Li Qingzhao%李清照爱国者形象的历史还原

    Institute of Scientific and Technical Information of China (English)

    魏青

    2015-01-01

    李清照无疑是一位爱国主义者,以宋室南渡为界,前期她对北宋新旧两党之争有相当的警觉,后期她对南宋最高统治集团的妥协投降政策极为不满。这两个方面在她的各类作品中得以充分展现。然而,她毕竟是一个生活在900多年前的闺阁弱女子,她的爱国主义自有其历史、阶级以及女性自我的局限性。我们既不能过分拔高她的爱国形象,借以提升她的历史地位,也不能低估乃至无视她的爱国思想的存在,而应当紧密结合她所处的时代、家世、遭遇等来评价其爱国主义的思想。%As a patriot beyond doubt,Li Qingzhao maintained sharp vigilance against the disputes of the two parties,i. e. the old and the new,of the Northern Song dynasty during the earlier period of her life, which is divided into the early and the later period with the crossing of the Yangtze River of Zhao Gou, the then Song Emperor,as the demarcation line;and was especially discontented with the policy of com-promise and capitulation of the highest hierarchy of the Southern Song dynasty during the later period. Both of which are fully demonstrated in her different genres of works. However,her patriotism bore its classical and historical limitations of women themselves,as she was nonetheless a weak lady from the boudoir nine hundred years ago. Therefore,the image of hers is not to be overestimated in order to elevate her position in history,her patriotic thoughts are not to be underestimated and/or even ignored either. Her ideological level of patriotism is to be evaluated in combination with her times,family background and experience. Any subjective elevation or depreciation with no history basis can hardly be convincing.

  9. A Robust Algorithm for Blind Total Variation Restoration

    Institute of Scientific and Technical Information of China (English)

    Jing Xu; Qian-shun Chang

    2008-01-01

    Image restoration is a fundamental problem in image processing. Blind image restoration has a great value in its practical application. However, it is not an easy problem to solve due to its complexity and difficulty. In this paper, we combine our robust algorithm for known blur operator with an alternating minimization implicit iterative scheme to deal with blind deconvolution problem, recover the image and identify the point spread function(PSF). The only assumption needed is satisfy the practical physical sense. Numerical experiments demonstrate that this minimization algorithm is efficient and robust over a wide range of PSF and have almost the same results compared with known PSF algorithm.

  10. SURVEY AND RESTORATION

    Directory of Open Access Journals (Sweden)

    C. Mileto

    2017-05-01

    Full Text Available In addition to the technological evolution over the last two centuries, survey has experienced two main conceptual leaps: the introduction of photography as a tool for an indiscriminate register for reality, and the shift from autographic to allographic survey, phenomena which can generate a distancing effect within the restoration process. Besides, this text presents the relationship between survey in its numerous forms and technologies (manual and semi-manual to more complex ones like scanner-laser and the restoration of the building, either for establishing a diagnosis, operating or valorizating, illustrating it with examples developed by the authors, as well as the criteria to be applied when documenting a building to be restored, irrespective of the means and technology available in each case.

  11. [New direct restorative materials].

    Science.gov (United States)

    Hickel, R; Dasch, W; Janda, R; Tyas, M; Anusavice, K

    1999-04-01

    People worldwide have become increasingly aware of the potential adverse effects on the environment, of pollution control and of toxic effects of food, drugs and biomaterials. Amalgam and its potential toxic side effects (still scientifically unproven) continue to be discussed with increasing controversy by the media in some countries. Consequently, new direct restorative materials are now being explored by dentists, materials scientists and patients who are searching for the so-called 'amalgam substitute' or 'amalgam alternative'. From a critical point of view some of the new direct restorative materials are good with respect in aesthetics, but all material characteristics must be considered, such as mechanical properties, biological effects, and longterm clinical behaviour.

  12. 基于加权小波变换及MTFC的多光谱影像融合方法%An Image Fusion Method Based on Multi-phase Wavelet Transformation and MTFC Restoration

    Institute of Scientific and Technical Information of China (English)

    张炳先; 何红艳; 李岩

    2015-01-01

    IHS(intensity-hue-saturation)变换是影像融合实际生产中使用最多的一种方法,而小波变换是近几年来影像融合中的热门研究方向。但是现有方法存在纹理畸变和光谱畸变的现象,尤其是当地物光谱特性在全色和多光谱中存在较大差异的时候,融合后光谱畸变将会十分突出。为了解决上述问题,在分析现有小波变换方法的基础上提出了一种基于加权小波变换及调制传递函数补偿(MTFC)的多光谱影像融合方法,通过引入多相位小波变换的方式来抑制小波变换产生的纹理畸变,同时通过引入MTFC的方法来恢复影像融合中丢失的纹理信息。文章选用“高分二号”卫星影像来验证算法的有效性,试验结果表明,与现有的融合方法相比,文章中提出的算法能够很好地抑制影像中的光谱畸变,同时保留更多的有效纹理信息。%AbstractImage fusion is an important tool to fuse high spectral and high spatial information into one image for image interpretation and target recognition in remote sensing application. To date, many image fusion methods have been developed, among which IHS technique is the most widely used, and the wavelet fusion is the most frequently discussed in recent publications due to its obvious advantages. However, the available methods can hardly produce a satisfactory fusion result, in which spectral and spatial distortions often take place, especially when spectral properties of the same surface features are different between natural color images and panchromatic ones. To solve the problem, we propose a new method by introducing a multi-phase approach to restrain spatial distortion caused by the shift variant attribution of wavelet transformation. With suitable rules of fusion, the method uses modulation transfer function compensation (MTFC) to restore details, so that the spectral distortion can be avoided. The performance of the method was

  13. Accelerated gradient methods for total-variation-based CT image reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Joergensen, Jakob H.; Hansen, Per Christian [Technical Univ. of Denmark, Lyngby (Denmark). Dept. of Informatics and Mathematical Modeling; Jensen, Tobias L.; Jensen, Soeren H. [Aalborg Univ. (Denmark). Dept. of Electronic Systems; Sidky, Emil Y.; Pan, Xiaochuan [Chicago Univ., Chicago, IL (United States). Dept. of Radiology

    2011-07-01

    Total-variation (TV)-based CT image reconstruction has shown experimentally to be capable of producing accurate reconstructions from sparse-view data. In particular TV-based reconstruction is well suited for images with piecewise nearly constant regions. Computationally, however, TV-based reconstruction is demanding, especially for 3D imaging, and the reconstruction from clinical data sets is far from being close to real-time. This is undesirable from a clinical perspective, and thus there is an incentive to accelerate the solution of the underlying optimization problem. The TV reconstruction can in principle be found by any optimization method, but in practice the large scale of the systems arising in CT image reconstruction preclude the use of memory-intensive methods such as Newton's method. The simple gradient method has much lower memory requirements, but exhibits prohibitively slow convergence. In the present work we address the question of how to reduce the number of gradient method iterations needed to achieve a high-accuracy TV reconstruction. We consider the use of two accelerated gradient-based methods, GPBB and UPN, to solve the 3D-TV minimization problem in CT image reconstruction. The former incorporates several heuristics from the optimization literature such as Barzilai-Borwein (BB) step size selection and nonmonotone line search. The latter uses a cleverly chosen sequence of auxiliary points to achieve a better convergence rate. The methods are memory efficient and equipped with a stopping criterion to ensure that the TV reconstruction has indeed been found. An implementation of the methods (in C with interface to Matlab) is available for download from http://www2.imm.dtu.dk/~pch/TVReg/. We compare the proposed methods with the standard gradient method, applied to a 3D test problem with synthetic few-view data. We find experimentally that for realistic parameters the proposed methods significantly outperform the standard gradient method. (orig.)

  14. Restoration of nonlinear motion-distorted composite frame

    Science.gov (United States)

    Yitzhaky, Yitzhak; Stern, Adrian; Kopeika, Norman S.

    2000-12-01

    A composite frame image is an interlaced composition of two sub-image odd and even fields. Such image type is common in many imaging systems that produce video sequences. When relative motion between the camera and the scene occurs during the imaging process, two types of distortion degrade the image: the edge 'staircase effect' due to the shifted appearances of the objects in successive fields, and blur due to the scene motion during each field exposure. This paper deals with restoration of composite frame images degraded by motion. In contrast to other previous works that dealt with only uniform velocity motion, here we consider a more general case of nonlinear motion. Since conventional motion identification techniques used in other works can not be employed in the case of nonlinear motion, a new method for identification of the motion from each field is used. Results of motion identification and image restoration for various motion types are presented.

  15. [Influence of implant restoration on traditional restoration idea].

    Science.gov (United States)

    Liu, H C

    2016-01-01

    Implant restoration affected the traditional restoration idea. Artificial implant restoration has a profound influence on the design of dental restoration. Implant supported prostheses have not only changed the method of oral rehabilitation, but also integrated revolutionary concept with the traditional treatment protocol. By using implants, posterior missing molars can be effectively restored and thus eliminating the disadvantages of traditional removable partial denture for Kennedy classification Ⅰ, Ⅱ partically edentulous dentition. Full edentulous arch can also be restored with implant fixed denture which provide much better oral health related quality of life compared with the traditional complete denture. It is useful to master the theory and skills of artificial implant restoration, and to provide a reference for the restoration of oral physiological function.

  16. Papahanaumokuakea - Laysan Island Restoration 2010

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Goal of the Laysan Island Restoration is to restore Laysan to a "Pristine" state which would require minimal monitoring and habitat for Endemic Endangered...

  17. Deblured Gaussian Blurred Images

    CERN Document Server

    Al-amri, Salem Saleh; D, Khamitkar S

    2010-01-01

    This paper attempts to undertake the study of Restored Gaussian Blurred Images. by using four types of techniques of deblurring image as Wiener filter, Regularized filter, Lucy Richardson deconvlutin algorithm and Blind deconvlution algorithm with an information of the Point Spread Function (PSF) corrupted blurred image with Different values of Size and Alfa and then corrupted by Gaussian noise. The same is applied to the remote sensing image and they are compared with one another, So as to choose the base technique for restored or deblurring image.This paper also attempts to undertake the study of restored Gaussian blurred image with no any information about the Point Spread Function (PSF) by using same four techniques after execute the guess of the PSF, the number of iterations and the weight threshold of it. To choose the base guesses for restored or deblurring image of this techniques.

  18. Relativistic Linear Restoring Force

    Science.gov (United States)

    Clark, D.; Franklin, J.; Mann, N.

    2012-01-01

    We consider two different forms for a relativistic version of a linear restoring force. The pair comes from taking Hooke's law to be the force appearing on the right-hand side of the relativistic expressions: d"p"/d"t" or d"p"/d["tau"]. Either formulation recovers Hooke's law in the non-relativistic limit. In addition to these two forces, we…

  19. Megasessions for Robotic Hair Restoration.

    Science.gov (United States)

    Pereira, Joa O Carlos; Pereira Filho, Joa O Carlos; Cabrera Pereira, Joa O Pedro

    2016-11-01

    A robotic system can select and remove individual hair follicles from the donor area with great precision and without fatigue. This report describes the use of the robotic system in a megasession for hair restoration. Patients were instructed to cut their hair to 1.0 to 1.2 mm before surgery. The robot selected and removed 600 to 800 grafts per hour so the follicular units (FU)s could be transplanted manually to recipient sites. The robot arm consists of a sharp inner punch and a blunt outer punch which together separate FUs from the sur- rounding tissue. Stereoscopic cameras controlled by image processing software allow the system to identify the angle and direction of hair growth. The physician and one assistant control the harvesting with a hand-held remote control and computer monitor while the patient is positioned in an adjustable chair. When the robot has harvested all the FUs they are removed by technicians with small forceps. Hairline design, creation of recipient sites, and graft placement are performed manually by the physician. Clinical photographs before and after surgery show that patients experience excellent outcomes with the robotic megasession. Phy- sician fatigue during graft extraction is reduced because the robot performs the repetitive movements without fatigue. Variability of graft extraction is minimized because the robot's optical system can be programmed to choose the best FUs. The transection rate is reduced because the robot's graft extraction system uses two needles, a sharp one to piece the skin and a blunt needle to dissect the root without trauma. A robotic megasession for hair restoration is minimally invasive, does not result in linear scars in the donor area, and is associated with minimal fatigue and discomfort for both patient and physician. Healing is rapid and patients experience a high level of satisfaction with the results. J Drugs Dermatol. 2016;15(11):1407-1412..

  20. 口腔金属修复材料对磁共振图像和锥形束CT图像伪影的影响%The Artifacts on MR imaging and Cone Beam CT Caused by Dental Metallic Restorative Materials

    Institute of Scientific and Technical Information of China (English)

    武婧; 李文晋

    2016-01-01

    The MR imaging and cone beam computed tomography radiographic inspection techniques have had an increasing applications in the field of oral medicine.The metallic materials commonly used in dental restoration can produce different degree of artifacts on the CBCT and MRI images,which interfere the clinical diagnosis.This article is made to have a summary for the research of the relationship between artifacts on the CBCT and MRI images and dental metallic restorative materials in recent years ,which is aimed to be convenient to be the guider in clinical work.%磁共振成像(Magnetic Resonance Imaging,MRI)与锥形束计算机体层成像(Cone Beam Computed Tomography,CBCT )影像学检查技术在口腔医学领域的应用日趋增加。金属材料在口腔修复中的应用占有不可或缺的地位,但其在CBCT与MRI图像上产生不同程度的伪影,对临床诊断造成干扰。本文就近年来针对金属修复材料在CBCT与MRI伪影的相关研究进行总结与简述,便于口腔临床工作应用提供参考。

  1. [Imaging].

    Science.gov (United States)

    Chevrot, A; Drapé, J L; Godefroy, D; Dupont, A M; Pessis, E; Sarazin, L; Minoui, A

    1997-01-01

    The panoply of imaging techniques useful in podology is essentially limited to X-rays. Standard "standing" and "lying" X-rays furnish most of the required information. Arthrography is sometimes performed, in particular for trauma or tumour of the ankle. CT scan and MRI make a decisive contribution in difficult cases, notably in fractures and in small fractures without displacement. The two latter techniques are useful in tendon, ligament and muscular disorders, where echography is also informative. Rigorous analysis of radiographies and a good knowledge of foot disorders make these imaging techniques efficacious.

  2. An Improved Total Variation Minimization Method Using Prior Images and Split-Bregman Method in CT Reconstruction

    Science.gov (United States)

    2016-01-01

    Compressive Sensing (CS) theory has great potential for reconstructing Computed Tomography (CT) images from sparse-views projection data and Total Variation- (TV-) based CT reconstruction method is very popular. However, it does not directly incorporate prior images into the reconstruction. To improve the quality of reconstructed images, this paper proposed an improved TV minimization method using prior images and Split-Bregman method in CT reconstruction, which uses prior images to obtain valuable previous information and promote the subsequent imaging process. The images obtained asynchronously were registered via Locally Linear Embedding (LLE). To validate the method, two studies were performed. Numerical simulation using an abdomen phantom has been used to demonstrate that the proposed method enables accurate reconstruction of image objects under sparse projection data. A real dataset was used to further validate the method. PMID:27689076

  3. Longevity of silicate ceramic restorations.

    Science.gov (United States)

    Beier, Ulrike Stephanie; Dumfahrt, Herbert

    2014-09-01

    The demand for esthetic restorations has resulted in an increased use of dental ceramics as a biocompatible and functionally sufficient alternative to conventional restorative materials. Silicate ceramic restorations are widely used for veneers, inlays, onlays, and crowns in dentistry. Long-term data are of crucial importance to optimize clinical practice. The purpose of the present article is to summarize data of the Innsbruck ceramic evaluation up to 261 months with the focus on longevity and failure characteristics.

  4. Evaluation of the dental structure loss produced during maintenance and replacement of occlusal amalgam restorations

    Directory of Open Access Journals (Sweden)

    Fernanda Sardenberg

    2008-09-01

    Full Text Available The aim of this in vitro study was to evaluate four different approaches to the decision of changing or not defective amalgam restorations in first primary molar teeth concerning the loss of dental structure. Ditched amalgam restorations (n = 11 were submitted to four different treatments, as follows: Control group - polishing and finishing of the restorations were carried out; Amalgam group - the ditched amalgam restorations were replaced by new amalgam restorations; Composite resin group - the initial amalgam restorations were replaced by composite resin restorations; Flowable resin group - the ditching around the amalgam restorations was filled with flowable resin. Images of the sectioned teeth were made and the area of the cavities before and after the procedures was determined by image analysis software to assess structural loss. The data were submitted to ANOVA complemented by the Student Newman Keuls test (p < 0.05. The cavities in all the groups presented significantly greater areas after the procedures. However, the amalgam group showed more substantial dental loss. The other three groups presented no statistically significant difference in dental structure loss after the re-treatments. Thus, replacing ditched amalgam restorations by other similar restorations resulted in a significant dental structure loss while maintaining them or replacing them by resin restorations did not result in significant loss.

  5. Evaluation of the dental structure loss produced during maintenance and replacement of occlusal amalgam restorations.

    Science.gov (United States)

    Sardenberg, Fernanda; Bonifácio, Clarissa Calil; Braga, Mariana Minatel; Imparato, José Carlos Pettorossi; Mendes, Fausto Medeiros

    2008-01-01

    The aim of this in vitro study was to evaluate four different approaches to the decision of changing or not defective amalgam restorations in first primary molar teeth concerning the loss of dental structure. Ditched amalgam restorations (n = 11) were submitted to four different treatments, as follows: Control group - polishing and finishing of the restorations were carried out; Amalgam group - the ditched amalgam restorations were replaced by new amalgam restorations; Composite resin group - the initial amalgam restorations were replaced by composite resin restorations; Flowable resin group - the ditching around the amalgam restorations was filled with flowable resin. Images of the sectioned teeth were made and the area of the cavities before and after the procedures was determined by image analysis software to assess structural loss. The data were submitted to ANOVA complemented by the Student Newman Keuls test (p structure loss after the re-treatments. Thus, replacing ditched amalgam restorations by other similar restorations resulted in a significant dental structure loss while maintaining them or replacing them by resin restorations did not result in significant loss.

  6. Technologies for lake restoration

    Directory of Open Access Journals (Sweden)

    Helmut KLAPPER

    2003-09-01

    Full Text Available Lakes are suffering from different stress factors and need to be restored using different approaches. The eutrophication remains as the main water quality management problem for inland waters: both lakes and reservoirs. The way to curb the degradation is to stop the nutrient sources and to accelerate the restoration with help of in-lake technologies. Especially lakes with a long retention time need (eco- technological help to decrease the nutrient content in the free water. The microbial and other organic matter from sewage and other autochthonous biomasses, causes oxygen depletion, which has many adverse effects. In less developed countries big reservoirs function as sewage treatment plants. Natural aeration solves problems only partly and many pollutants tend to accumulate in the sediments. The acidification by acid rain and by pyrite oxidation has to be controlled by acid neutralizing technologies. Addition of alkaline chemicals is useful only for soft waters, and technologies for (microbial alkalinization of very acidic hardwater mining lakes are in development. The corrective measures differ from those in use for eutrophication control. The salinization and water shortage mostly occurs if more water is used than available. L. Aral, L. Tschad, the Dead Sea or L. Nasser belong to waters with most severe environmental problems on a global scale. Their hydrologic regime needs to be evaluated. The inflow of salt water at the bottom of some mining lakes adds to stability of stratification, and thus accumulation of hydrogen sulphide in the monimolimnion of the meromictic lakes. Destratification, which is the most used technology, is only restricted applicable because of the dangerous concentrations of the byproducts of biological degradation. The contamination of lakes with hazardous substances from industry and agriculture require different restoration technologies, including subhydric isolation and storage, addition of nutrients for better self

  7. Skjern River Restoration Counterfactual

    DEFF Research Database (Denmark)

    Clemmensen, Thomas Juel

    2014-01-01

    In 2003 the Skjern River Restoration Project in Denmark was awarded the prestigious Europa Nostra Prize for ‘conserving the European cultural heritage’ (Danish Nature Agency 2005). In this case, however, it seems that the conservation of one cultural heritage came at the expense of another cultural...... of Dissonance in Nature Restoration’, Journal of Landscape Architecture 2/2014: 58-67. Danish Nature Agency (2005), Skjern Å: Ådalens historie. De store projekter. Det nye landskab og naturen. På tur i ådalen [The Skjern River: The History of the River Delta. The Big Projects. The New Landscape and Nature...... heritage. While the meanders of the Skjern River were reconstructed according to its assumed course in 1870s, the embanked canal, which was the main feature and symbol of a comprehensive cultivation project from the 1960s, was deconstructed and reduced to incomprehensible traces of the past. Not only did...

  8. Archived film analysis and restoration

    NARCIS (Netherlands)

    Rares, A.

    2004-01-01

    The progressive degradation of current film archives poses a serious threat to the preservation of our cultural and technical heritage. Digitization and digital restoration are currently the most viable solutions for the long term preservation and high quality restoration of filmed material. They

  9. SOCIAL WELFARE AND RESTORATIVE JUSTICE

    Directory of Open Access Journals (Sweden)

    Darrell Fox

    2009-09-01

    Full Text Available This paper explores the links and connections between social work and restorative justice. After a brief description of social work, restorative justice and family group conferencing, I will explore some the complementary theoretical links and practice applications, critically examining the potential implications and opportunities for social work practitioners and academics in relation to practice.

  10. Archived film analysis and restoration

    NARCIS (Netherlands)

    Rares, A.

    2004-01-01

    The progressive degradation of current film archives poses a serious threat to the preservation of our cultural and technical heritage. Digitization and digital restoration are currently the most viable solutions for the long term preservation and high quality restoration of filmed material. They al

  11. Evaluating Visual and Auditory Contributions to the Cognitive Restoration Effect

    Directory of Open Access Journals (Sweden)

    Adam G. Emfield

    2014-06-01

    Full Text Available It has been suggested that certain real-world environments can have a restorative effect on an individual, as expressed in changes in cognitive performance and mood. Much of this research builds on Attention Restoration Theory (ART, which suggests that environments that have certain characteristics induce cognitive restoration via variations in attentional demands. Specifically, natural environments that require little top-down processing have a positive effect on cognitive performance, while city-like environments show no effect. We characterized the cognitive restoration effect further by examining 1 whether natural visual stimuli, such as blue spaces, were more likely to provide a restorative effect over urban visual stimuli, 2 if increasing immersion with environment-related sound produces a similar or superior effect, 3 if this effect extends to other cognitive tasks, such as the functional field of view, and 4 if we could better understand this effect by providing controls beyond previous works. We had 202 participants complete a cognitive task battery, consisting of a reverse digit span task, the attention network task, and the functional field of view task prior to and immediately after a restoration period. In the restoration period, participants were assigned to one of seven conditions in which they listened to natural or urban sounds, watched images of natural or urban environments, or a combination of both. Additionally, some participants were in a control group with exposure to neither picture nor sound. While we found some indication of practice effects, there were no differential effects of restoration observed in any of our cognitive tasks, regardless of condition. We did, however, find evidence that our nature images and sounds were more relaxing than their urban counterparts. Overall, our findings suggest that acute exposure to relaxing pictorial and auditory stimulus is insufficient to induce improvements in cognitive

  12. Identification of Acceptable Restoration Strategies

    Directory of Open Access Journals (Sweden)

    Seung-Tae Cha

    2008-04-01

    Full Text Available In recent years, we have seen several catastrophic and cascading failures of power systems throughout the world. Power system breakup and blackouts are rare events. However, when they occur, the effects on utilities and general population can be quite severe. To prevent or reduce cascading sequences of events caused by the various reasons, KEPRI is researching ways to revolutionize innovative strategies that will significantly reduce the vulnerability of the power system and will ensure successful restoration of service to customers. This paper describes a restoration guidelines / recommendations for the KEPS simulator, which allows power system operator and planner to simulate and plan restoration events in an interactive mode. The KEPS simulator provides a list of restoration events according to the priority based on some restoration rules and list of priority loads. Further, the paper will draw on research using information from a Jeju case study.

  13. Restoration of optic neuropathy

    Directory of Open Access Journals (Sweden)

    You SW

    2017-03-01

    . Many genes, such as Bcl-2, PTEN, and mTOR, are crucial in cell proliferation, axon guidance, and growth during development, and play important roles in the regeneration and extension of RGC axons. With transgenic mice and related gene regulations, robust regeneration of RGC axons has been observed after ON injury in laboratories. Although various means of experimental treatments such as cell transplantation and gene therapy have achieved significant progress in neuronal survival, axonal regeneration, and restoration of the visual function after ON injury, many unresolved scientific problems still exist for their clinical applications. Therefore, we still need to overcome hurdles before developing effective therapy to treat optic neuropathy diseases in patients. Keywords: retinal ganglion cells, optic nerve injury, neuronal survival, axonal regeneration, vision restoration

  14. Utilizing optical coherence tomography for CAD/CAM of indirect dental restorations

    Science.gov (United States)

    Chityala, Ravishankar; Vidal, Carola; Jones, Robert

    Optical Coherence Tomography (OCT) has seen broad application in dentistry including early carious lesion detection and imaging defects in resin composite restorations. This study investigates expanding the clinical usefulness by investigating methods to use OCT for obtaining three-dimensional (3D) digital impressions, which can be integrated to CAD/CAM manufacturing of indirect restorations. 3D surface topography `before' and `after' a cavity preparation was acquired by an intraoral cross polarization swept source OCT (CP-OCT) system with a Micro-Electro-Mechanical System (MEMS) scanning mirror. Image registration and segmentation methods were used to digitally construct a replacement restoration that modeled the original surface morphology of a hydroxyapatite sample. After high resolution additive manufacturing (e.g. polymer 3D printing) of the replacement restoration, micro-CT imaging was performed to examine the marginal adaptation. This study establishes the protocol for further investigation of integrating OCT with CAD/CAM of indirect dental restorations.

  15. Restoration of GERIS Data Using the Maximum Noise Fractions Transform

    DEFF Research Database (Denmark)

    Nielsen, Allan Aasbjerg; Larsen, Rasmus

    1994-01-01

    The Maximum Noise Fractions (MNF) transformation is used as a restoration tool in a 512512 subscene of a 63 channel spectral dataset recorded over the Pyrite Belt in Southern Spain with the Geophysical Environmental Research Imaging Spectrometer (GERIS). The data obtained from such a scanning...

  16. Fernald restoration: ecologists and engineers integrate restoration and cleanup

    Energy Technology Data Exchange (ETDEWEB)

    Woods, Eric; Homer, John

    2002-07-15

    As cleanup workers excavate pits and tear down buildings at the Fernald site in southwest Ohio, site ecologists are working side-by-side to create thriving wetlands and develop the early stages of forest, prairie, and savanna ecosystems to restore natural resources that were impacted by years of site operations. In 1998, the U.S. Department of Energy-Fernald Office (DOE-FN) and its cleanup contractor, Fluor Fernald, Inc., initiated several ecological restoration projects in perimeter areas of the site (e.g., areas not used for or impacted by uranium processing or waste management). The projects are part of Fernald's final land use plan to restore natural resources over 904 acres of the 1,050-acre site. Pete Yerace, the DOE-FN Natural Resource Trustee representative is working with the Fernald Natural Resource Trustees in an oversight role to resolve the state of Ohio's 1986 claim against DOE for injuries to natural resources. Fluor Fernald, Inc., and DOE-FN developed the ''Natural Resource Restoration Plan'', which outlines 15 major restoration projects for the site and will restore injured natural resources at the site. In general, Fernald's plan includes grading to maximize the formation of wetlands or expanded floodplain, amending soil where topsoil has been removed during excavation, and establishing native vegetation throughout the site. Today, with cleanup over 35 percent complete and site closure targeted for 2006, Fernald is entering a new phase of restoration that involves heavily remediated areas. By working closely with engineers and cleanup crews, site ecologists can take advantage of remediation fieldwork (e.g., convert an excavated depression into a wetland) and avoid unnecessary costs and duplication. This collaboration has also created opportunities for relatively simple and inexpensive restoration of areas that were discovered during ongoing remediation. To ensure the survival of the plant material in heavily

  17. VT River Restoration Data in Lamoille County

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) Documented river and riparian buffer restoration projects in Lamoille County, Vermont. Restoration includes buffer plantings (trees and shrubs),...

  18. Wetland Restoration and Sediment Removal

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — In 2008, Minnesota’s Private Lands Program and Wetland Management Districts began to compare different methods of restoring prairie pothole wetlands to see if there...

  19. Papahanaumokuakea - Laysan Island Restoration 2011

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This project supports restoration activities at Laysan Island. Staff and volunteers continue efforts to eradicate alien invasive species such as Indian dropseed...

  20. Papahanaumokuakea - Laysan Island Restoration 2009

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This project will support restoration activities at Laysan Island. Staff and volunteers continue efforts to eradicate alien invasive species such as Indian dropseed...

  1. Wetlands Restoration Definitions and Distinctions

    Science.gov (United States)

    Ecological restoration is a valuable endeavor that has proven very difficult to define. The term indicates that degraded and destroyed natural wetland systems will be reestablished to sites where they once existed. But, what wetland ecosystems are we talki

  2. Basic research for environmental restoration

    Energy Technology Data Exchange (ETDEWEB)

    1990-12-01

    The Department of Energy (DOE) is in the midst of a major environmental restoration effort to reduce the health and environmental risks resulting from past waste management and disposal practices at DOE sites. This report describes research needs in environmental restoration and complements a previously published document, DOE/ER-0419, Evaluation of Mid-to-Long Term Basic Research for Environmental Restoration. Basic research needs have been grouped into five major categories patterned after those identified in DOE/ER-0419: (1) environmental transport and transformations; (2) advanced sampling, characterization, and monitoring methods; (3) new remediation technologies; (4) performance assessment; and (5) health and environmental effects. In addition to basic research, this document deals with education and training needs for environmental restoration. 2 figs., 6 tabs.

  3. [Pulp response to restorative materials].

    Science.gov (United States)

    Advokaat, J G

    1990-03-01

    Restorations may affect the pulp negatively, rather due to microleakage than to toxic properties of the materials used. Hyperalgesia occurs more frequently after restoration with composite resins than with amalgam, though the resins in contrast to amalgam may be bonded to the enamel margins. A number of recommendations are presented in order to minimize the marginal gap between cavity walls and amalgam and to prevent marginal fracture.

  4. Boosting of Image Denoising Algorithms

    OpenAIRE

    Romano, Yaniv; Elad, Michael

    2015-01-01

    In this paper we propose a generic recursive algorithm for improving image denoising methods. Given the initial denoised image, we suggest repeating the following "SOS" procedure: (i) (S)trengthen the signal by adding the previous denoised image to the degraded input image, (ii) (O)perate the denoising method on the strengthened image, and (iii) (S)ubtract the previous denoised image from the restored signal-strengthened outcome. The convergence of this process is studied for the K-SVD image ...

  5. Linear methods for input scenes restoration from signals of optical-digital pattern recognition correlator

    Science.gov (United States)

    Starikov, Sergey N.; Konnik, Mikhail V.; Manykin, Edward A.; Rodin, Vladislav G.

    2009-04-01

    Linear methods of restoration of input scene's images in optical-digital correlators are described. Relatively low signal to noise ratio of a camera's photo sensor and extensional PSF's size are special features of considered optical-digital correlator. RAW-files of real correlation signals obtained by digital photo sensor were used for input scene's images restoration. It is shown that modified evolution method, which employs regularization by Tikhonov, is better among linear deconvolution methods. As a regularization term, an inverse signal to noise ratio as a function of spatial frequencies was used. For additional improvement of restoration's quality, noise analysis of boundary areas of the image to be reconstructed was performed. Experimental results on digital restoration of input scene's images are presented.

  6. Stable Restoration and Separation of Approximately Sparse Signals

    CERN Document Server

    Studer, Christoph

    2011-01-01

    This paper develops new theory and algorithms to recover signals that are approximately sparse in some general (i.e., basis, frame, over-complete, or in-complete) dictionary but corrupted by a combination of measurement noise and interference having a sparse representation in a second general dictionary. Particular applications covered by our framework include the restoration of signals impaired by impulse noise, narrowband interference, or saturation, as well as image in-painting, super-resolution, and signal separation. We develop efficient recovery algorithms and deterministic conditions that guarantee stable restoration and separation. Two application examples demonstrate the efficacy of our approach.

  7. THE RESTORATIVE CLASSROOM: Using Restorative Approaches to Foster Effective Learning

    Directory of Open Access Journals (Sweden)

    Reviewed by Martha A. BROWN

    2012-04-01

    Full Text Available The book is divided into three sections. Part One, chapters 1-3, provides the reader with a framework for understanding relational and restorative pedagogy based on the Five Key Restorative Themes: Everyone has their own unique and equally valued perspectives Thoughts influence emotions, emotions influence actions Empathy and consideration Needs and unmet needs Collective responsibility for problem solving and decision making. (Hopkins, 2011, p.32These five themes form the basis for the rest of the book. Part Two, chapters 4-9, describes a range of restorative practices and exercises, such as mixers, circles, and community-building games, as well as the step-by-step instructions on how to implement and conduct them. Part Three, Chapter 10, succinctly discusses the whole-school approach, which is explained in greater detail in Just Schools (Hopkins, 2004. Still, Hopkins would be remiss not to emphasize the need for the whole-school adoption of restorative practices based on current school effectiveness and improvement literature, and again asserts that "developing a restorative staffroom and staff team is likely to be a pre-requisite for a successful, high-achieving school" (Hopkins, 2011, p. 225.

  8. A Systematic Study of Zerbar Lake Restoration

    Science.gov (United States)

    Hosseini, Reza; Oveis Torabi, Seyed; Forman Asgharzadeh, Deonna

    2017-04-01

    The beautiful lake of Zerbar, located near Marivan City at the west of Iran, is a freshwater lake with an area of 20 km2 and average depth of 5 meters. The lake is created by regional tectonic activities and is mainly fed with natural spring water from bottom. During the past three decades, regional development has caused much disturbance to the natural environment of the lake and its watershed. Rescuing the lake is crucial to the sustainability of the whole region. The study of Zerbar Restoration was performed with the aim to restore its health indicators. Variety of human activities in the watershed, as well as the multidisciplinary nature of lake restoration studies, made it necessary to develop a systematic approach to conduct the study. In Step I of restoration studies, satellite images were investigated to identify the historical changes of watershed during the past 30 years. Meanwhile, documents since 50 years ago were studied. Results indicate that farmland and graze land areas have been relatively constant during the past 50 years. Also, the area of lake, its riparian canes and floating plants have not changed much. In fact, the only significant land use change observed was the significant spread of Marivan City that has stretched toward the lake. The main physical variation to the lake has been elevating the southern edge of the lake by a constructing a landfill dam which was done to control the lake's overflow discharge for irrigation of downstream farmland development. Step II consists of studies performed by disciplines of water resources, hydrogeology, water quality, wetland and watershed ecology, agriculture, animal farming and fishery. Study results indicate that eutrophication (TSL>100), mainly caused by sewage from Marivan City and the surrounding rural areas has been the main reason for lake ecosystem degradation. DPSIR framework, as a novel approach in lake restoration, was applied to synthesize the study results of different disciplines in a

  9. Image Inpainting

    Directory of Open Access Journals (Sweden)

    A. A. Kondekar

    2014-09-01

    Full Text Available Inpainting refers to the art of restoring lost parts of image and reconstructing them based on the background information i.e Image inpainting is the process of reconstructing lost or deteriorated parts of images using information from surrounding areas. In fine art museums, inpainting of degraded paintings is traditionally carried out by professional artists and usually very time consuming.The purpose of inpainting is to reconstruct missing regions in a visually plausible manner so that it seems reasonable to the human eye. There have been several approaches proposed for the same. This paper gives an overview of different Techniques of Image Inpainting.The proposed work includes the overview of PDE based inpainting algorithm and Texture synthesis based inpainting algorithm. This paper presents a brief survey on comparative study of these two techniques used for Image Inpainting.

  10. Restoration of primary anterior teeth: review of the literature.

    Science.gov (United States)

    Lee, Jacob K

    2002-01-01

    This paper reviews the published data on restorations of primary anterior teeth. The discussion includes Class III restorations, Class V restorations, various forms of full coronal restorations, atraumatic restorative technique (ART) and recommendations for future research.

  11. Color Restoration Method Based on Spectral Information Using Normalized Cut

    Institute of Scientific and Technical Information of China (English)

    Tetsuro Morimoto; Tohru Mihashi; Katsushi Ikeuchi

    2008-01-01

    This paper proposes a novel method for color restoration that can effectively apply accurate color based on spectral information to a segmented image using the normalized cut technique. Using the proposed method, we can obtain a digital still camera image and spectral information in different environments. Also, it is not necessary to estimate reflectance spectra using a spectral database such as other methods. The synthesized images are accurate and high resolution. The proposed method effectively works in making digital archive contents. Some experimental results are demonstrated in this paper.

  12. 76 FR 46149 - Financial Assistance: Wildlife Restoration, Sport Fish Restoration, Hunter Education and Safety

    Science.gov (United States)

    2011-08-01

    ... Assistance: Wildlife Restoration, Sport Fish Restoration, Hunter Education and Safety; Final Rule #0;#0... Restoration, Hunter Education and Safety AGENCY: Fish and Wildlife Service, Interior. ACTION: Final rule... Restoration, Sport Fish Restoration, and Hunter Education and Safety (Enhanced Hunter Education and...

  13. A multiresolution restoration method for cardiac SPECT

    Science.gov (United States)

    Franquiz, Juan Manuel

    Single-photon emission computed tomography (SPECT) is affected by photon attenuation and image blurring due to Compton scatter and geometric detector response. Attenuation correction is important to increase diagnostic accuracy of cardiac SPECT. However, in attenuation-corrected scans, scattered photons from radioactivity in the liver could produce a spillover of counts into the inferior myocardial wall. In the clinical setting, blurring effects could be compensated by restoration with Wiener and Metz filters. Inconveniences of these procedures are that the Wiener filter depends upon the power spectra of the object image and noise, which are unknown, while Metz parameters have to be optimized by trial and error. This research develops an alternative restoration procedure based on a multiresolution denoising and regularization algorithm. It was hypothesized that this representation leads to a more straightforward and automatic restoration than conventional filters. The main objective of the research was the development and assessment of the multiresolution algorithm for compensating the liver spillover artifact. The multiresolution algorithm decomposes original SPECT projections into a set of sub-band frequency images. This allows a simple denoising and regularization procedure by discarding high frequency channels and performing inversion only in low and intermediate frequencies. The method was assessed in bull's eye polar maps and short- axis attenuation-corrected reconstructions of a realistic cardiac-chest phantom with a custom-made liver insert and different 99mTc liver-to-heart activity ratios. Inferior myocardial defects were simulated in some experiments. The cardiac phantom in free air was considered as the gold standard reference. Quantitative analysis was performed by calculating contrast of short- axis slices and the normalized chi-square measure, defect size and mean and standard deviation of polar map counts. The performance of the multiresolution

  14. Methodology for ranking restoration options

    DEFF Research Database (Denmark)

    Jensen, Per Hedemann

    1999-01-01

    The work described in this report has been performed as a part of the RESTRAT Project FI4P-CT95-0021a (PL 950128) co-funded by the Nuclear Fission Safety Programme of the European Commission. The RESTRAT project has the overall objective of developinggeneric methodologies for ranking restoration...... techniques as a function of contamination and site characteristics. The project includes analyses of existing remediation methodologies and contaminated sites, and is structured in the following steps:-characterisation of relevant contaminated sites -identication and characterisation of relevant restoration...... techniques -assessment of the radiological impact -development and application of a selection methodology for restoration options -formulation ofgeneric conclusions and development of a manual The project is intended to apply to situations in which sites with nuclear installations have been contaminated...

  15. Decision analysis in restorative dentistry.

    Science.gov (United States)

    Anusavice, K J

    1992-12-01

    Standardization of clinical decisions in restorative dentistry should be based on the tenets of the Hippocratic Oath. Although there is wide variability in preventive and operative treatment decisions, some of these decisions may lead along parallel courses to similar, clinically ethical outcomes. However, what parameters must be considered in judging the relative magnitude of positive and negative outcomes? This paper proposes several decision-making strategies for selecting optimum treatment plans for preventive and restorative situations. The caries-risk level of patients must first be identified in a systematic way and then it must be coupled with treatment options that are consistent with the potential future caries increment. A decision-tree approach and/or the treatment-index concept can then be applied to specific clinical conditions and preventive-restorative options to derive an "expected value" for each possible outcome.

  16. Visual field restorative rehabilitation after brain injury.

    Science.gov (United States)

    Matteo, Barbara Maria; Viganò, Barbara; Cerri, Cesare Giuseppe; Perin, Cecilia

    2016-07-01

    About 20%-30% of patients undergoing neurological rehabilitation report visual field defects, one of the most frequent of which is homonymous hemianopsia (loss of the same half of the visual field in both eyes). There is still no consensus as to whether homonymous hemianopsia is best treated in a restorative or compensatory manner. The aim of this review is to describe the effects of restorative rehabilitation, whose long-term efficacy is still being debated. We analyzed 56 articles describing the use of various techniques used to promote visual field recovery but concentrating on two approaches: "border training," which involves exercising vision at the edge of the damaged visual field, and "blindsight training," which is based on exercising unconscious perceptual functions in the mild of the blind hemifield where the scotoma is deep. Both techniques have been supported by functional imaging studies showing evidence of cortical rearrangement (plasticity) after rehabilitation. Although no formal meta-analysis was possible, the results of a semiquantitative evaluation suggested that the improvement in visual skills obtained is related to the type of training used: Border rehabilitation seems to improve the detection of visual stimuli, whereas blindsight rehabilitation seems to improve their processing. Finally, the addition of transcranial direct current stimulation seems to enhance the effects of visual field rehabilitation.

  17. Interactions of liposomes with dental restorative materials.

    Science.gov (United States)

    Nguyen, Sanko; Adamczak, Malgorzata; Hiorth, Marianne; Smistad, Gro; Kopperud, Hilde Molvig

    2015-12-01

    The in vitro adsorption and retention of liposomes onto four common types of dental restorative materials (conventional and silorane-based resin composites as well as conventional and resin-modified glass ionomer cements (GIC)) have been investigated due to their potential use in the oral cavity. Uncoated liposomes (positively and negatively charged) and pectin (low- and high-methoxylated) coated liposomes were prepared and characterized in terms of particle size and zeta potential. The adsorption of liposomes was performed by immersion, quantified by fluorescence detection, and visualized by fluorescence imaging and atomic force microscopy. Positive liposomes demonstrated the highest adsorption on all four types of materials likely due to their attractive surface charge. They also retained well (minimum 40% after 60 min) on both conventional resin composite and GIC even when exposed to simulated salivary flow. Although an intermediate initial level of adsorption was found for the pectin coated liposomes, at least 70% high methoxylated-pectin coated liposomes still remained on the conventional resin composite after 60 min flow exposure. This indicates significant contribution of hydrophobic interactions in the prolonged binding of liposomes to resin composites. Based on these results, the present paper suggests two new possible applications of liposomes in the preservation of dental restorations.

  18. Short-term improvement of masticatory function after implant restoration

    Science.gov (United States)

    2015-01-01

    Purpose Dental implants present several advantages over other tooth replacement options. However, there has been little research on masticatory function in relation to implant treatment. Therefore, the aim of the present study was to evaluate the improvement of masticatory function two weeks after implant restoration. Methods Masticatory ability was evaluated with the subjective food intake ability (FIA) and objective mixing ability index (MAI) methods. Fifty-four subjects with first and second missing molars completed the study. The subjects were asked to complete a self-reported questionnaire about 30 different food items, and to chew wax samples 10 times both before and two weeks after implant restoration. A total of 108 waxes were analyzed with an image analysis program. Results Dental implant restoration for lost molar teeth on one side increased the FIA score by 9.0% (P<0.0001). The MAI score also increased, by 14.3% after implant restoration (P<0.0001). Comparison between the good and poor mastication groups, which were subdivided based on the median MAI score before implant restoration, showed that the FIA score of the poor group was enhanced 1.1-fold while its MAI score was enhanced 2.0-fold two weeks after an implant surgery. Conclusions Using the FIA and MAI assessment methods, this study showed that masticatory function was improved two weeks after implant restoration. In particular, the enhancement of masticatory function by implant restoration was greater in patients with relatively poor initial mastication than in those with good initial mastication. PMID:26734490

  19. Conservative preparations for cast restorations.

    Science.gov (United States)

    Shillingburg, H T

    1976-04-01

    Partial veneer crowns still play a role in modern restorative dentistry. They must be used in the right situation with thoughtful treatment planning, and they must be done well in accordance with certain principles. Three-quarter crowns are less retentive than full crowns, but they can be used successfully as single unit restorations and retainers for short span bridges. Retention can be enhanced by the use of proximal boxes. The M.O.D. onlay, a modified inlay with occlusal coverage, minimizes the damaging effects of stress generated by occlusal forces. There is little indication for the use of M.O.D. inlays or large two surface inlays.

  20. Influence of different restorative techniques on marginal seal of class II composite restorations

    Directory of Open Access Journals (Sweden)

    Sinval Adalberto Rodrigues Junior

    2010-02-01

    Full Text Available OBJECTIVE: To evaluate the gingival marginal seal in class II composite restorations using different restorative techniques. MATERIAL AND METHODS: Class II box cavities were prepared in both proximal faces of 32 sound human third molars with gingival margins located in either enamel or dentin/cementum. Restorations were performed as follows: G1 (control: composite, conventional light curing technique; G2: composite, soft-start technique; G3: amalgam/composite association (amalcomp; and G4: resin-modified glass ionomer cement/composite, open sandwich technique. The restored specimens were thermocycled. Epoxy resin replicas were made and coated for scanning electron microscopy examination. For microleakage evaluation, teeth were coated with nail polish and immersed in dye solution. Teeth were cut in 3 slices and dye penetration was recorded (mm, digitized and analyzed with Image Tool software. Microleakage data were analyzed statistically by non-parametric Kruskal-Wallis and Mann-Whitney tests. RESULTS: Leakage in enamel was lower than in dentin (p<0.001. G2 exhibited the lowest leakage values (p<0.05 in enamel margins, with no differences between the other groups. In dentin margins, groups G1 and G2 had similar behavior and both showed less leakage (p<0.05 than groups G3 and G4. SEM micrographs revealed different marginal adaptation patterns for the different techniques and for the different substrates. CONCLUSION: The soft-start technique showed no leakage in enamel margins and produced similar values to those of the conventional (control technique for dentin margins.

  1. A Full Snow Season in Yellowstone: A Database of Restored Aqua Band 6

    Science.gov (United States)

    Gladkova, Irina; Grossberg, Michael; Bonev, George; Romanov, Peter; Riggs, George; Hall, Dorothy

    2013-01-01

    The algorithms for estimating snow extent for the Moderate Resolution Imaging Spectroradiometer (MODIS) optimally use the 1.6- m channel which is unavailable for MODIS on Aqua due to detector damage. As a test bed to demonstrate that Aqua band 6 can be restored, we chose the area surrounding Yellowstone and Grand Teton national parks. In such rugged and difficult-to-access terrain, satellite images are particularly important for providing an estimation of snow-cover extent. For the full 2010-2011 snow season covering the Yellowstone region, we have used quantitative image restoration to create a database of restored Aqua band 6. The database includes restored radiances, normalized vegetation index, normalized snow index, thermal data, and band-6-based snow-map products. The restored Aqua-band-6 data have also been regridded and combined with Terra data to produce a snow-cover map that utilizes both Terra and Aqua snow maps. Using this database, we show that the restored Aqua-band-6-based snow-cover extent has a comparable performance with respect to ground stations to the one based on Terra. The result of a restored band 6 from Aqua is that we have an additional band-6 image of the Yellowstone region each day. This image can be used to mitigate cloud occlusion, using the same algorithms used for band 6 on Terra. We show an application of this database of restored band-6 images to illustrate the value of creating a cloud gap filling using the National Aeronautics and Space Administration s operational cloud masks and data from both Aqua and Terra.

  2. Origins of the Restoration Playhouse.

    Science.gov (United States)

    Wilson, Dennis D.

    Contrary to the popular theory that the proscenium type of playhouse was imported from France by the Court of Charles II in 1660, the Restoration playhouse in fact developed from Elizabethan theatres and court masques. These Elizabethan theatres were the private theatres, and were generally small, rectangular, roofed structures where aristocratic…

  3. Zirconia-reinforced dental restorations

    NARCIS (Netherlands)

    C. Chen

    2013-01-01

    The series of studies conducted in this thesis showed that there are several ways to enhance the performance of fixed restorations regarding the application of zirconia. One possible way is to change the sintering procedure of zirconia, so that the physical properties of zirconia such BFS, density o

  4. Weed biocontrol in landscape restoration

    Science.gov (United States)

    Weed biological control programs in natural areas are often undertaken with the goal of restoring native plant communities and/or ecosystem services to a pre-invasion level. These objectives may be achieved in some areas with biological control alone; however, in other sites integration of biologica...

  5. A review on anterior teeth restorations

    Directory of Open Access Journals (Sweden)

    Gaurav Solanki

    2014-12-01

    Full Text Available Restorations of teeth have been a need of time since very long. As the time have passed, there have been different advances in the field of restorative materials and tooth restorations. Many newer restorative materials are now available to us for the purpose of tooth restorations still some of the older materials are materials of choice for a sector of society. This article focuses on few such restorative materials and also tells us about a few patents granted in such field.

  6. Research on fog-degraded image restoration based on bilateral filter of RGB channel%基于双边滤波的RGB通道去雾算法研究

    Institute of Scientific and Technical Information of China (English)

    游谦; 黎英; 李玉成; 赵虎; 王振

    2014-01-01

    因大气光的散射和入射光的衰减,大雾天气下捕获到的图像质量呈指数系数下降。为改善退化图像的视觉效果,利用暗原色先验信息获得大气光;根据单幅雾天图像RGB通道强度估计场景深度图;同时在明亮区域引入一种容差阈值,避免了这部分区域场景深度的错误估计,使用带边缘保持的双边滤波器对求得的场景深度图进一步处理;利用大气散射模型实现了图像复原。实验结果表明,改进后的算法有效提高了雾天退化图像的视觉效果。%Due to scattering of atmospheric light and attenuation of incident light, the quality of images captured under foggy conditions will be reduced exponentially to the scene depth. In order to improve the visual effect of the degraded image, this paper makes use of the dark channel to estimate the air light. According to the strength of RGB channel, then, the scene depth map is estimated from a single fog image. Moreover, this paper introduces a tolerance threshold in the bright region to avoid the error estimates of the scene depth. A bilateral filter with edge-preserving is utilized to further process the scene depth map. A clear image can be recovered based on the atmospheric scattering model. Experiment results show that the proposed improved algorithm can enhance the visibility of fog-degraded images effectively.

  7. Phonemic restoration in developmental dyslexia

    Directory of Open Access Journals (Sweden)

    Stephanie N. Del Tufo

    2014-06-01

    Full Text Available The comprehension of fluent speech in one’s native language requires that listeners integrate the detailed acoustic-phonetic information available in the sound signal with linguistic knowledge. This interplay is especially apparent in the phoneme restoration effect, a phenomenon in which a missing phoneme is ‘restored’ via the influence of top-down information from the lexicon and through bottom-up acoustic processing. Developmental dyslexia is a disorder characterized by an inability to read at the level of one’s peers without any clear failure due to environmental influences. In the current study we utilized the phonemic restoration illusion paradigm, to examine individual differences in phonemic restoration across a range of reading ability, from very good to dyslexic readers. Results demonstrate that restoration occurs less in those who have high scores on measures of phonological processing. Based on these results, we suggest that the processing or representation of acoustic detail may not be as reliable in poor and dyslexic readers, with the result that lexical information is more likely to override acoustic properties of the stimuli. This pattern of increased restoration could result from a failure of perceptual tuning, in which unstable representations of speech sounds result in the acceptance of non-speech sounds as speech. An additional or alternative theory is that degraded or impaired phonological processing at the speech sound level may reflect architecture that is overly plastic and consequently fails to stabilize appropriately for speech sound representations. Therefore the inability to separate speech and noise may result as a deficit in separating noise from the acoustic signal.

  8. Clinical cross-polarization optical coherence tomography assessment of subsurface enamel below dental resin composite restorations.

    Science.gov (United States)

    Lenton, Patricia; Rudney, Joel; Fok, Alex; Jones, Robert S

    2014-04-01

    A newly designed intraoral swept source cross-polarization optical coherence tomography (CP-OCT) imaging system was used to examine the integrity of the subsurface enamel below resin composite restorations placed in primary teeth. CP-OCT analysis was performed using images obtained from resin composite restoration in 62 ([Formula: see text]) pediatric subjects. Clinical examination was performed by a single examiner prior to CP-OCT imaging and analysis. CP-OCT images are presented using a unique combined intensity image, where a false color scale is overlaid on the grayscale intensity image. There was a clear difference in the distribution of the mean-backscattered intensity (mR) between restorations recently placed and those possessing frank cavitation (Student's t-test, [Formula: see text]). For mR above 15.49 dB, the sensitivity was 80% and specificity 86%. The Youden index J was 0.8 above 12.3 dB where sensitivity was 100% and specificity was 80%. CP-OCT imaging may be used to confirm the subsurface marginal integrity below resin composite restorations but with careful consideration of limitations of the imaging modality. CP-OCT imaging may be a useful adjunct to clinical visual investigation to confirm that a composite margin has a sound and well-adapted interface.

  9. Skeletonization methods for image and volume inpainting

    NARCIS (Netherlands)

    Sobiecki, Andre

    2016-01-01

    Image and shape restoration techniques are increasingly important in computer graphics. Many types of restoration techniques have been proposed in the 2D image-processing and according to our knowledge only one to volumetric data. Well-known examples of such techniques include digital inpainting,

  10. Skeletonization methods for image and volume inpainting

    NARCIS (Netherlands)

    Sobiecki, Andre

    2016-01-01

    Image and shape restoration techniques are increasingly important in computer graphics. Many types of restoration techniques have been proposed in the 2D image-processing and according to our knowledge only one to volumetric data. Well-known examples of such techniques include digital inpainting, de

  11. Use of interdisciplinary team approach in establishing esthetic restorative dentistry.

    Science.gov (United States)

    Almog, Dov M; Meitner, Sean W; Even-Hen, Neer; Grant, Joshua P; Soltys, James L

    2005-01-01

    Managing crown lengthening in cases of attrition (wear or loss of tooth substance) and achieving desired esthetic outcomes, especially in the esthetic zone, is challenging. This case report presents an interdisciplinary approach to case management. Concomitant use of digital imaging, along with model wax-ups and surgical guide, were used to enhance patient acceptance during treatment planning and to facilitate communication and treatment implementation among dental professionals and laboratory technicians. Resulting surgical template was used for crown lengthening to apically position the gingival zenith (margin) to a predetermined level, crown preps and final restorations, respectively, ultimately improving esthetics and patient satisfaction. Supplementing esthetic treatment planning with digital imaging, model wax-ups and a surgical template allows a dentist to carry information into the mouth and incorporate it into the surgical procedure, crown preps, temps and, ultimately, the final restoration.

  12. Technology needs for environmental restoration remedial action. Environmental Restoration Program

    Energy Technology Data Exchange (ETDEWEB)

    Watson, J.S.

    1992-11-01

    This report summarizes the current view of the most important technology needs for the US Department of Energy (DOE) facilities operated by Martin Marietta Energy Systems, Inc. These facilities are the Oak Ridge National Laboratory, the Oak Ridge K-25 Site, the Oak Ridge Y-12 Plant, the Paducah Gaseous Diffusion Plant, and the Portsmouth Gaseous Diffusion Plant. The sources of information used in this assessment were a survey of selected representatives of the Environmental Restoration (ER) programs at each facility, results from a questionnaire distributed by Geotech CWM, Inc., for DOE, and associated discussions with individuals from each facility. This is not a final assessment, but a brief look at an ongoing assessment; the needs will change as the plans for restoration change and, it is hoped, as some technical problems are solved through successful development programs.

  13. Comparative Study of Image Denoising Algorithms in Digital Image Processing

    Directory of Open Access Journals (Sweden)

    Aarti

    2014-05-01

    Full Text Available This paper proposes a basic scheme for understanding the fundamentals of digital image processing and the image denising algorithm. There are three basic operation categorized on during image processing i.e. image rectification and restoration, enhancement and information extraction. Image denoising is the basic problem in digital image processing. The main task is to make the image free from Noise. Salt & pepper (Impulse noise and the additive white Gaussian noise and blurredness are the types of noise that occur during transmission and capturing. For denoising the image there are some algorithms which denoise the image.

  14. Comparative Study of Image Denoising Algorithms in Digital Image Processing

    Directory of Open Access Journals (Sweden)

    Aarti Kumari

    2015-11-01

    Full Text Available This paper proposes a basic scheme for understanding the fundamentals of digital image processing and the image denising algorithm. There are three basic operation categorized on during image processing i.e. image rectification and restoration, enhancement and information extraction. Image denoising is the basic problem in digital image processing. The main task is to make the image free from Noise. Salt & pepper (Impulse noise and the additive white Gaussian noise and blurredness are the types of noise that occur during transmission and capturing. For denoising the image there are some algorithms which denoise the image.

  15. Segmentation and Analysis of Corpus Callosum in Alzheimer MR Images using Total Variation Based Diffusion Filter and Level Set Method.

    Science.gov (United States)

    Anandh, K R; Sujatha, C M; Ramakrishnan, S

    2015-01-01

    Alzheimer’s Disease (AD) is a common form of dementia that affects gray and white matter structures of brain. Manifestation of AD leads to cognitive deficits such as memory impairment problems, ability to think and difficulties in performing day to day activities. Although the etiology of this disease is unclear, imaging biomarkers are highly useful in the early diagnosis of AD. Magnetic resonance imaging is an indispensible non-invasive imaging modality that reflects both the geometry and pathology of the brain. Corpus Callosum (CC) is the largest white matter structure as well as the main inter-hemispheric fiber connection that undergoes regional alterations due to AD. Therefore, segmentation and feature extraction are predominantly essential to characterize the CC atrophy. In this work, an attempt has been made to segment CC using edge based level set method. Prior to segmentation, the images are pre-processed using Total Variation (TV) based diffusion filtering to enhance the edge information. Shape based geometric features are extracted from the segmented CC images to analyze the CC atrophy. Results show that the edge based level set method is able to segment CC in both the normal and AD images. TV based diffusion filtering has performed uniform region specific smoothing thereby preserving the texture and small scale details of the image. Consequently, the edge map of CC in both the normal and AD are apparently sharp and distinct with continuous boundaries. This facilitates the final contour to correctly segment CC from the nearby structures. The extracted geometric features such as area, perimeter and minor axis are found to have the percentage difference of 5.97%, 22.22% and 9.52% respectively in the demarcation of AD subjects. As callosal atrophy is significant in the diagnosis of AD, this study seems to be clinically useful.

  16. Digital color restoration of old paintings.

    Science.gov (United States)

    Pappas, M; Pitas, I

    2000-01-01

    Physical and chemical changes can degrade the visual color appearance of old paintings. Five digital color restoration techniques, which can be used to simulate the original appearance of paintings, are presented. Although a small number of color samples is employed in the restoration procedure, simulation results indicate that good restoration quality can be attained.

  17. 5 CFR 353.301 - Restoration rights.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Restoration rights. 353.301 Section 353... DUTY FROM UNIFORMED SERVICE OR COMPENSABLE INJURY Compensable Injury § 353.301 Restoration rights. (a.... Although these restoration rights are agencywide, the employee's basic entitlement is to the...

  18. Radiographic diagnosis of dental restoration misfit: a systematic review.

    Science.gov (United States)

    Liedke, G S; Spin-Neto, R; da Silveira, H E D; Wenzel, A

    2014-12-01

    The objective of this study was to perform a systematic review on the use of radiographic methods for the diagnosis of misfit in dental prostheses and restorations. The MEDLINE bibliographic database was searched from 1950 to February 2014 for reports on the radiographic diagnosis of misfits. The search strategy was limited to English-language publications using the following combined MeSH terms in the search strategy: (Dental Restoration OR Dental Prosthesis OR Crown OR Inlays OR Dental Abutments) and (Dental Leakage OR Prosthesis Fitting OR Dental Marginal Adaptation OR Surface Properties) and (Radiography, Dental OR Radiography, Dental, Digital OR Cone-Beam Computed Tomography). Twenty-eight publications were identified and read in full text, and 14 studies fulfilled criteria for inclusion. Information regarding the use of radiographic methods for the diagnosis of misfits in dental prosthesis and restorations, and in which the methodology/results comprised information regarding how the sample was collected/prepared, the method, imaging protocol, presence of a reference test and the outcomes were evaluated. QUADAS criteria was used to rate the studies in high, moderate or low quality. The evidence supporting the use of radiographic methods for the diagnosis of misfits in dental prosthesis and restorations is limited to low-/moderate-quality studies. The well-established intra-oral orthogonal projection is still under investigation and considered the most appropriate method, both when evaluating the relation between dental restoration to tooth and abutment to implant. Studies using digital radiographs have not evaluated the effect of image post-processing, and tomography has not been evaluated.

  19. Resilience and Restoration of Lakes

    Directory of Open Access Journals (Sweden)

    Kathryn L. Cottingham

    1997-06-01

    Full Text Available Lake water quality and ecosystem services are normally maintained by several feedbacks. Among these are nutrient retention and humic production by wetlands, nutrient retention and woody habitat production by riparian forests, food web structures that cha nnel phosphorus to consumers rather than phytoplankton, and biogeochemical mechanisms that inhibit phosphorus recycling from sediments. In degraded lakes, these resilience mechanisms are replaced by new ones that connect lakes to larger, regional economi c and social systems. New controls that maintain degraded lakes include runoff from agricultural and urban areas, absence of wetlands and riparian forests, and changes in lake food webs and biogeochemistry that channel phosphorus to blooms of nuisance al gae. Economic analyses show that degraded lakes are significantly less valuable than normal lakes. Because of this difference in value, the economic benefits of restoring lakes could be used to create incentives for lake restoration.

  20. UV completion without symmetry restoration

    CERN Document Server

    Endlich, Solomon; Penco, Riccardo

    2013-01-01

    We show that it is not possible to UV-complete certain low-energy effective theories with spontaneously broken space-time symmetries by embedding them into linear sigma models, that is, by adding "radial" modes and restoring the broken symmetries. When such a UV completion is not possible, one can still raise the cutoff up to arbitrarily higher energies by adding fields that transform non-linearly under the broken symmetries, that is, new Goldstone bosons. However, this (partial) UV completion does not necessarily restore any of the broken symmetries. We illustrate this point by considering a concrete example in which a combination of space-time and internal symmetries is broken down to a diagonal subgroup. Along the way, we clarify a recently proposed interpretation of inverse Higgs constraints as gauge-fixing conditions.

  1. Articulator selection for restorative dentistry.

    Science.gov (United States)

    Hobo, S; Shillingburg, H T; Whitsett, L D

    1976-07-01

    There are many types of articulators that can be used for making fixed restorations. While unquestionably the most accurate, the fully adjustable instrument is not feasible or necessary for many forms of simple occlusal treatment. The effects of tooth-hinge axis radius, intercondylar distance, and condylar inclination on occlusal morphology have been discussed. Guidelines have been proposed for matching the type of articulator with the extent of treatment anticipated. The use of small, nonadjustable hinge articulators is not recommended.

  2. Minimum thickness anterior porcelain restorations.

    Science.gov (United States)

    Radz, Gary M

    2011-04-01

    Porcelain laminate veneers (PLVs) provide the dentist and the patient with an opportunity to enhance the patient's smile in a minimally to virtually noninvasive manner. Today's PLV demonstrates excellent clinical performance and as materials and techniques have evolved, the PLV has become one of the most predictable, most esthetic, and least invasive modalities of treatment. This article explores the latest porcelain materials and their use in minimum thickness restoration.

  3. Procedures for restoring vestibular disorders

    OpenAIRE

    2005-01-01

    This paper will discuss therapeutic possibilities for disorders of the vestibular organs and the neurons involved, which confront ENT clinicians in everyday practice. Treatment of such disorders can be tackled either symptomatically or causally. The possible strategies for restoring the body's vestibular sense, visual function and co-ordination include medication, as well as physical and surgical procedures. Prophylactic or preventive measures are possible in some disorders which involve vert...

  4. Methodology for ranking restoration options

    Energy Technology Data Exchange (ETDEWEB)

    Hedemann Jensen, Per

    1999-04-01

    The work described in this report has been performed as a part of the RESTRAT Project FI4P-CT95-0021a (PL 950128) co-funded by the Nuclear Fission Safety Programme of the European Commission. The RESTRAT project has the overall objective of developing generic methodologies for ranking restoration techniques as a function of contamination and site characteristics. The project includes analyses of existing remediation methodologies and contaminated sites, and is structured in the following steps: characterisation of relevant contaminated sites; identification and characterisation of relevant restoration techniques; assessment of the radiological impact; development and application of a selection methodology for restoration options; formulation of generic conclusions and development of a manual. The project is intended to apply to situations in which sites with nuclear installations have been contaminated with radioactive materials as a result of the operation of these installations. The areas considered for remedial measures include contaminated land areas, rivers and sediments in rivers, lakes, and sea areas. Five contaminated European sites have been studied. Various remedial measures have been envisaged with respect to the optimisation of the protection of the populations being exposed to the radionuclides at the sites. Cost-benefit analysis and multi-attribute utility analysis have been applied for optimisation. Health, economic and social attributes have been included and weighting factors for the different attributes have been determined by the use of scaling constants. (au)

  5. Comparison of Composite Restoration Techniques

    Directory of Open Access Journals (Sweden)

    András Katona

    2016-01-01

    Full Text Available This article briefly presents the classification, and possible ways of application of composites. Our objective was to compare three different restoration technique in class II cavity preparations, with the aim to determine which technique is the most advantageous in practical point of view. Artificial teeth fabricated from self-curing acrylic resin were used as models. Comparison of marginal sealing was performed macroscopically via direct visual inspection and via tactile control. Two parameters were examined on esthetic evaluation, which were the anatomical shape and the optical appearance. The time required to prepare the restorations were also measured. After the evaluation of the results, the bulk-fill technique was demonstrated to require the shortest time to be performed. This was followed by the oblique (Z technique, whereas the horizontal incremental technique appeared to be the most time-consuming method. Based on the esthetic evaluation, a remarkable difference can be observed between the bulk-fill technique and the other two incremental techniques, while the mean scores for the oblique and the horizontal techniques were comparable. Based on the results of the visual inspection and instrumental examination, there were no differences in terms of marginal sealing between the three applied methods. Based on these, the use of the appropriate incremental technique can reduce the development of secondary caries and increasing the longevity of composite restorations.

  6. Materials for chairside CAD/CAM restorations.

    Science.gov (United States)

    Fasbinder, Dennis J

    2010-01-01

    Chairside computer-aided design/computer-aided manufacturing (CAD/CAM) systems have become considerably more accurate, efficient, and prevalent as the technology has evolved in the past 25 years. The initial restorative material option for chairside CAD/CAM restorations was limited to ceramic blocks. Restorative material options have multiplied and now include esthetic ceramics, high-strength ceramics, and composite materials for both definitive and temporary restoration applications. This article will review current materials available for chairside CAD/CAM restorations.

  7. A proposal of microtomography evaluation for restoration interface gaps

    Directory of Open Access Journals (Sweden)

    Deborah Meleo

    2012-01-01

    Full Text Available Nowadays, several adhesive systems are used in dental restoration and they’re evaluated by clinical research. In vitro evaluations are often made by means of traditional observation techniques (for example scanning electron microscope (SEM, while 3D cone-beam microtomography technique (3D micro-CT, that can be able to generate 3D sample images without any sample treatment during acquisition data, is going to be used a lot in the next few years. In dental cavity restored with composite, it is possible to predict the presence of gaps due to polymerization shrinkage; that is the reason this work purpose is to reveal by 3D images and measure by micro-CT analysis the voids generated applying the most used adhesive systems at the moment. By means of microtomographic analysis is proposed an aid to overcome bidimensional SEM investigation limits like random observation of sample surface, sample sectioning (to see inside it with the relative possible structural alterations induced on the same sample and the gold sputtering treatment. For this experimental work, human crown teeth have been selected, all restored with the same composite material, using five adhesive systems. After about 48 hours each tooth has been acquired by means of Skyscan 1072 micro-CT instrument and then processed by 3D reconstruction and micro-CT analyser software. Three adhesive systems have showed 3D micro-CT images with not as much voids as expected, with a very little extent. This kind of micro-CT in vitro evaluation proposal suggests a method to observe and quantify the voids generated after polymerization shrinkage during tooth restoration.

  8. The science and practice of river restoration

    Science.gov (United States)

    Wohl, Ellen; Lane, Stuart N.; Wilcox, Andrew C.

    2015-08-01

    River restoration is one of the most prominent areas of applied water-resources science. From an initial focus on enhancing fish habitat or river appearance, primarily through structural modification of channel form, restoration has expanded to incorporate a wide variety of management activities designed to enhance river process and form. Restoration is conducted on headwater streams, large lowland rivers, and entire river networks in urban, agricultural, and less intensively human-altered environments. We critically examine how contemporary practitioners approach river restoration and challenges for implementing restoration, which include clearly identified objectives, holistic understanding of rivers as ecosystems, and the role of restoration as a social process. We also examine challenges for scientific understanding in river restoration. These include: how physical complexity supports biogeochemical function, stream metabolism, and stream ecosystem productivity; characterizing response curves of different river components; understanding sediment dynamics; and increasing appreciation of the importance of incorporating climate change considerations and resiliency into restoration planning. Finally, we examine changes in river restoration within the past decade, such as increasing use of stream mitigation banking; development of new tools and technologies; different types of process-based restoration; growing recognition of the importance of biological-physical feedbacks in rivers; increasing expectations of water quality improvements from restoration; and more effective communication between practitioners and river scientists.

  9. The Assessment of Experimental Methods of Serial Number Restoration

    Science.gov (United States)

    Argo, Mackenzie

    Serial number restoration is a common and successful process of revealing obliterated serial numbers on firearms. In a crime laboratory setting, obliterated serial numbers are commonly processed in order to tie a person to a crime scene or provide an investigative lead for officers. Currently serial numbers are restored using a chemical etchant method that can eat away at the metal on the firearm even after the examination is complete. It can also take several hours to complete and only provide an examiner with a partial number. There are other nondestructive options however little to no literature is available. The purpose of this study is to discover new methods for nondestructive serial number restoration and to compare them to the traditional chemical method used. Metal bars of premeasured obliteration depths and different compositions were examined using three proposed experimental methods: near infrared imaging, cold frost, and scanning acoustic microscopy. Results did not indicate significant difference in the median number of visible digits recovered for each of the three proposed methods compared to the traditional chemical method. There were significant results in the median number of composition utilized and depth of obliteration. This indicates that different firearm compositions and depth of obliteration has an effect on serial number restoration.

  10. Fracture resistance of endodontically treated teeth restored with indirect composite inlay and onlay restorations – An in vitro study

    Directory of Open Access Journals (Sweden)

    Ibraheem F. Alshiddi

    2016-01-01

    Conclusion: Within the limitations of this study, endodontically treated teeth were successfully restored with indirect composite inlay and onlay restorations. However, the fractures that accompanied the inlay restorations were more severe and were unable to be restored.

  11. Long-term evaluation of extensive restorations in permanent teeth

    DEFF Research Database (Denmark)

    Nieuwenhuysen, J.-P. van; D'hoore, W.D.; Carvalho, J.;

    2003-01-01

    Biostatistics, cast crowns, complex restorations, composite resins, decision making, dental amalgam, metal ceramic crowns, multi-surfaced restorations, prosthodontics, restorative dentistry......Biostatistics, cast crowns, complex restorations, composite resins, decision making, dental amalgam, metal ceramic crowns, multi-surfaced restorations, prosthodontics, restorative dentistry...

  12. Factors influencing bonding fixed restorations

    Directory of Open Access Journals (Sweden)

    Medić Vesna

    2008-01-01

    Full Text Available INTRODUCTION Crown displacement often occurs because the features of tooth preparations do not counteract the forces directed against restorations. OBJECTIVE The purpose of this study was to evaluate the effect of preparation designs on retention and resistance of fixed restorations. METHOD The study was performed on 64 differently sized stainless steel dies. Also, caps which were used for evaluated retention were made of stainless steel for each die. After cementing the caps on experimental dies, measuring of necessary tensile forces to separate cemented caps from dies was done. Caps, which were made of a silver-palladium alloy with a slope of 60° to the longitudinal axis formed on the occlusal surface, were used for evaluating resistance. A sudden drop in load pressure recorded by the test machine indicated failure for that cap. RESULTS A significant difference was found between the tensile force required to remove the caps from the dies with different length (p<0.05 and different taper (p<0.01. The greatest retentive strengths (2579.2 N and 2989.8 N were noticed in experimental dies with the greatest length and smallest taper. No statistically significant (p>0.05 differences were found between tensile loads for caps cemented on dies with different diameter. Although there was an apparent slight increase in resistance values for caps on dies with smaller tapers, the increase in resistance for those preparation designs was not statistically significant. There was a significant difference among the resistance values for caps on dies with different length (p<0.01 and diameter (p<0.05. CONCLUSION In the light of the results obtained, it could be reasonably concluded that retention and resistance of the restoration is in inverse proportion to convergence angle of the prepared teeth. But, at a constant convergence angle, retention and resistance increase with rising length and diameter.

  13. A partial differential equation-based general framework adapted to Rayleigh′s, Rician′s and Gaussian′s distributed noise for restoration and enhancement of magnetic resonance image

    Directory of Open Access Journals (Sweden)

    Ram Bharos Yadav

    2016-01-01

    Full Text Available The proposed framework is obtained by casting the noise removal problem into a variational framework. This framework automatically identifies the various types of noise present in the magnetic resonance image and filters them by choosing an appropriate filter. This filter includes two terms: the first term is a data likelihood term and the second term is a prior function. The first term is obtained by minimizing the negative log likelihood of the corresponding probability density functions: Gaussian or Rayleigh or Rician. Further, due to the ill-posedness of the likelihood term, a prior function is needed. This paper examines three partial differential equation based priors which include total variation based prior, anisotropic diffusion based prior, and a complex diffusion (CD based prior. A regularization parameter is used to balance the trade-off between data fidelity term and prior. The finite difference scheme is used for discretization of the proposed method. The performance analysis and comparative study of the proposed method with other standard methods is presented for brain web dataset at varying noise levels in terms of peak signal-to-noise ratio, mean square error, structure similarity index map, and correlation parameter. From the simulation results, it is observed that the proposed framework with CD based prior is performing better in comparison to other priors in consideration.

  14. Contribution of genetics to ecological restoration.

    Science.gov (United States)

    Mijangos, Jose Luis; Pacioni, Carlo; Spencer, Peter B S; Craig, Michael D

    2015-01-01

    Ecological restoration of degraded ecosystems has emerged as a critical tool in the fight to reverse and ameliorate the current loss of biodiversity and ecosystem services. Approaches derived from different genetic disciplines are extending the theoretical and applied frameworks on which ecological restoration is based. We performed a search of scientific articles and identified 160 articles that employed a genetic approach within a restoration context to shed light on the links between genetics and restoration. These articles were then classified on whether they examined association between genetics and fitness or the application of genetics in demographic studies, and on the way the studies informed restoration practice. Although genetic research in restoration is rapidly growing, we found that studies could make better use of the extensive toolbox developed by applied fields in genetics. Overall, 41% of reviewed studies used genetic information to evaluate or monitor restoration, and 59% provided genetic information to guide prerestoration decision-making processes. Reviewed studies suggest that restoration practitioners often overlook the importance of including genetic aspects within their restoration goals. Even though there is a genetic basis influencing the provision of ecosystem services, few studies explored this relationship. We provide a view of research gaps, future directions and challenges in the genetics of restoration.

  15. Imaginative resonance training (IRT) achieves elimination of amputees' phantom pain (PLP) coupled with a spontaneous in-depth proprioception of a restored limb as a marker for permanence and supported by pre-post functional magnetic resonance imaging (fMRI).

    Science.gov (United States)

    Meyer, Paul; Matthes, Christoph; Kusche, Karl Erwin; Maurer, Konrad

    2012-05-31

    Non-pharmacological approaches such as mirror therapy and graded motor imagery often provide amelioration of amputees' phantom limb pain (PLP), but elimination has proved difficult to achieve. Proprioception of the amputated limb has been noted in studies to be defective and/or distorted in the presence of PLP, but has not, apparently, been researched for various stages of amelioration up to the absence of PLP. Previous studies using functional magnetic resonance imaging (fMRI) suggested that pathological cortical reorganisation after amputation may be the underlying neurobiological correlate of PLP. We report two cases of permanent elimination of PLP after application of imaginative resonance training. The patients, 69 years and 84 years old, reported freedom from PLP together with in-depth achievement of proprioception of a restored limb at the end of the treatment, which may thus be taken as an indication of permanence. Pre/post fMRI for the first case showed, against a group of healthy controls, analogous changes of activation in the sensorimotor cortex.

  16. Algorithm Design of Fuzzy Filter Based on Salt-and-Pepper Noise with High Probability in Image Restoration%基于高概率椒盐噪声的模糊滤波器在图像恢复中的算法设计

    Institute of Scientific and Technical Information of China (English)

    王贵君; 杨永强

    2015-01-01

    高概率椒盐噪声对数字图像的重度污染大量存在,如要消除信息少且噪点集中的噪声存在诸多困难;而低概率椒盐噪声对数字图像的轻度污染虽然可完全滤除,但在实际图像恢复中又缺少普遍意义。本文基于灰度值空间的模糊划分和描述灰度水平的模糊数,采用极值法对高概率噪声实施检测并建立恰当滤波窗口,应用广义重心去模糊化法和非噪声点对应的隶属函数设计一种新模糊滤波器。最后,通过仿真实例获得该滤波器可有效地过滤数字图像中高概率椒盐噪声,并说明它的去噪性能优于其他常见滤波器。%Severe pollution of salt-and-pepper noise with high probability in digital images is widespread ,such as to eliminate less information and noisy noise has many difficulties .Although light pollution of salt-and-pepper noise with low probability in digi-tal images can be completely removed ,it lacks of universal sense in actual image restoration .In this paper ,aimed at the fuzzy parti-tion in the gray-value spaces and fuzzy numbers describing the gray-value level ,the extreme value method is used to conduct the noise with the high probability test and establish the suitable filtering window .And then ,applying the defuzzification method of cen-ter of generalized gravity and the membership functions corresponding to the non-noise points to design a kind of new filter .Finally , we obtain that the filter can effectively filter the salt and pepper noise with high probability in digital images by simulation example , and its denoising performance is superior to other common filters .

  17. Mitochondrial DNA, restoring Beethovens music.

    Science.gov (United States)

    Merheb, Maxime; Vaiedelich, Stéphane; Maniguet, Thiérry; Hänni, Catherine

    2016-01-01

    Great ancient composers have endured many obstacles and constraints which are very difficult to understand unless we perform the restoration process of ancient music. Species identification in leather used during manufacturing is the key step to start such a restoration process in order to produce a facsimile of a museum piano. Our study reveals the species identification in the leather covering the hammer head in a piano created by Erard in 1802. This is the last existing piano similar to the piano that Beethoven used with its leather preserved in its original state. The leather sample was not present in a homogeneous piece, yet combined with glue. Using a DNA extraction method that avoids PCR inhibitors; we discovered that sheep and cattle are the origin of the combination. To identify the species in the leather, we focused on the amounts of mitochondrial DNA in both leather and glue and results have led us to the conclusion that the leather used to cover the hammer head in this piano was made of cattle hide.

  18. The material science of minimally invasive esthetic restorations.

    Science.gov (United States)

    Nový, Brian B; Fuller, Cameron E

    2008-01-01

    The term esthetic dentistry usually conjures up mental images of porcelain crowns and veneers. To some dentists, the term minimally invasive dentistry evokes thoughts of observing early lesions, and postponing treatment until lesions are closer to the pulp. (The World Congress of Minimally Invasive Dentistry defines minimally invasive dentistry as those techniques which respect health, function, and esthetics of oral tissue by preventing disease from occurring, or intercepting its progress with minimal tissue loss.) It would seem these two niches within dentistry are on opposite ends of the spectrum; however, composite resin and glass ionomer restorative materials unite these two ideologies. Understanding the limitations, benefits, and science behind each material allows clinicians to produce highly esthetic restorations that can resist future decay, internally remineralize the tooth, and help protect adjacent teeth from cariogenic attack.

  19. Biological restoration: A 4/5 crown

    Directory of Open Access Journals (Sweden)

    Monize Ferreira Figueiredo de Carvalho

    2013-01-01

    Full Text Available Dental caries is one of the most prevalent conditions in humans; the purpose of restorative dentistry is to recreate the anatomy of the affected tooth thus the use of fragments from natural teeth as an effective restorative method. A maxillary first premolar left was prepared for an inverted 4/5 crown due to involvement of the vestibular face, after prepared received an allogeneic collage with similar color and dimension. Follow-up after 12 months indicated a stable restoration. Clinically, the site was without signs of caries, migration of the fragment or marginal infiltration. Biological restoration is a viable alternative for reestablishing function and esthetics to damaged/decayed teeth and therefore, biological restoration as an alternative to other restorative options.

  20. Evaluating the process of ecological restoration

    Directory of Open Access Journals (Sweden)

    Christer Nilsson

    2016-03-01

    Full Text Available We developed a conceptual framework for evaluating the process of ecological restoration and applied it to 10 examples of restoration projects in the northern hemisphere. We identified three major phases, planning, implementation, and monitoring, in the restoration process. We found that evaluation occurred both within and between the three phases, that it included both formal and informal components, and that it often had an impact on the performance of the projects. Most evaluations were short-term and only some parts of them were properly documented. Poor or short-term evaluation of the restoration process creates a risk that inefficient methods will continue to be used, which reduces the efficiency and effectiveness of restoration. To improve the restoration process and to transfer the knowledge to future projects, we argue for more formal, sustained evaluation procedures, involving all relevant stakeholders, and increased and improved documentation and dissemination of the results.

  1. Shame and Guilt in Restorative Justice

    DEFF Research Database (Denmark)

    Rodogno, Raffaele

    2008-01-01

    in particular, having presented the aims of restorative justice, the importance of face-to-face conferences in reaching these aims, the emotional dynamics that take place within such conferences, and the relevant parts of the empirical psychology of shame and guilt, I argue that restorative justice......In this article, I examine the relevance and desirability of shame and guilt to restorative justice conferences. I argue that a careful study of the psychology of shame and guilt reveals that both emotions possess traits that can be desirable and traits that can be undesirable for restoration. More...... practitioners have to take account of a rather more complex picture than it had hitherto been thought. Restorative conferences are not simply about "shame management," though practitioners must certainly avoid shaming and humiliation. Given the nature of shame, guilt, and restorative conferences...

  2. [Odontogenic maxillary sinusitis caused by dental restoration].

    Science.gov (United States)

    Sato, Kiminori

    2014-06-01

    We report herein on 5 patients with odontogenic maxillary sinusitis caused by a dental restoration (caries cutting, cavity preparation, inlay restoration). Odontogenic maxillary sinusitis was noted following dental restoration. Even though the pulp cavity and dental pulp were intact, the odontogenic maxillary sinusitis occurred caused by an apical lesion. Infection by way of the dentinal tubules was suggested to be a cause of the pathophysiology. Endoscopic sinus surgery was indicated in patients with intractable odontogenic maxillary sinusitis caused by the dental restoration. Cone-beam x-ray CT was useful for the accurate diagnosis of odontogenic maxillary sinusitis caused by a dental restoration. Physicians should thus be aware of the possibility that a tooth, which has undergone dental restoration, may cause odontogenic maxillary sinusitis.

  3. Guidelines for Direct Adhesive Composite Restoration.

    Science.gov (United States)

    Society Of Cariology And Endodontology, Chinese Stomatological Association Csa

    2015-01-01

    Direct adhesive composite restoration, a technique to restore tooth defects by bonding composite resin materials, has been widely used in the restoration of dental caries or other tooth defects. Retention of composite resin restoration mainly relies on bonding strength between the materials and dental tissue. The clinical outcomes rely greatly on the regulated clinical practice of dentists. In 2011, the Society of Cariology and Endodontology of Chinese Stomatological Association (CSA) published the 'Practices and evaluation criteria of composite resin bonded restoration (Discussion Version)'. Since then, opinions and comments regarding the 'Discussion Version' have been widely circulated within the Society. The final version of the guideline was based on systematic reviews of scientific literature and requirements for the edit of technical guidelines, and through several rounds of discussions, revisions and supplements. The society recommends this guideline for clinicians to use in their practices, when conducting direct composite restorations.

  4. Architectural restoration: different conceptions during centuries

    Directory of Open Access Journals (Sweden)

    Salvatore Lorusso

    2002-02-01

    Full Text Available The work reassumes the fundamental phases, in reference to the historical changes, of the conceptions related to the restoration and to the maintenance of the architectural works of art. It is opportune to reassume the evolution of the methods and the techniques applied to the restoration of the aforesaid manufactured articles, also in relationship to the theoretical conceptions. The explication of the routine of restoration has concerned particularly the actual applications. Close to the theory and to the routine of the restoration it has been set in evidence the development of the concept of "maintenance", understood as preliminary and complementary to the restoration itself: such concept has been express referring to the Charters of restoration from the beginning of the last century to today. It is intended, therefore, to follow a historical-critical path conceived in the different, and also complementary, phases of historical, aesthetical and technological development.

  5. Can Viral Videos Help Beaver Restore Streams?

    Science.gov (United States)

    Castro, J. M.; Pollock, M. M.; Lewallen, G.; Jordan, C.; Woodruff, K.

    2015-12-01

    Have you watched YouTube lately? Did you notice the plethora of cute animal videos? Researchers, including members of our Beaver Restoration Research team, have been studying the restoration potential of beaver for decades, yet in the past few years, beaver have gained broad acclaim and some much deserved credit for restoration of aquatic systems in North America. Is it because people can now see these charismatic critters in action from the comfort of their laptops? While the newly released Beaver Restoration Guidebook attempts to answer many questions, sadly, this is not one of them. We do, however, address the use of beaver (Castor canadensis) in stream, wetland, and floodplain restoration and discuss the many positive effects of beaver on fluvial ecosystems. Our team, composed of researchers from NOAA National Marine Fisheries Service, US Fish and Wildlife Service, US Forest Service, and Portland State University, has developed a scientifically rigorous, yet accessible, practitioner's guide that provides a synthesis of the best available science for using beaver to improve ecosystem functions. Divided into two broad sections -- Beaver Ecology and Beaver Restoration and Management -- the guidebook focuses on the many ways in which beaver improve habitat, primarily through the construction of dams that impound water and retain sediment. In Beaver Ecology, we open with a discussion of the general effects that beaver dams have on physical and biological processes, and we close with "Frequently Asked Questions" and "Myth Busters". In Restoration and Management, we discuss common emerging restoration techniques and methods for mitigating unwanted beaver effects, followed by case studies from pioneering practitioners who have used many of these beaver restoration techniques in the field. The lessons they have learned will help guide future restoration efforts. We have also included a comprehensive beaver ecology library of over 1400 references from scientific journals

  6. Ecological feasibility studies in restoration decision making.

    Science.gov (United States)

    Hopfensperger, Kristine N; Engelhardt, Katharina A M; Seagle, Steven W

    2007-06-01

    The restoration of degraded systems is essential for maintaining the provision of valuable ecosystem services, including the maintenance of aesthetic values. However, restoration projects often fail to reach desired goals for a variety of ecologic, financial, and social reasons. Feasibility studies that evaluate whether a restoration effort should even be attempted can enhance restoration success by highlighting potential pitfalls and gaps in knowledge before the design phase of a restoration. Feasibility studies also can bring stakeholders together before a restoration project is designed to discuss potential disagreements. For these reasons, a feasibility study was conducted to evaluate the efficacy of restoring a tidal freshwater marsh in the Potomac River near Alexandria, Virginia. The study focused on science rather than engineering questions, and thus differed in approach from other feasibility studies that are mostly engineering driven. The authors report the framework they used to conduct a feasibility study to inform other potential restoration projects with similar goals. The seven steps of the framework encompass (1) initiation of a feasibility study, (2) compilation of existing data, (3) collection of current site information, (4) examination of case studies, (5) synthesis of information in a handbook, (6) meeting with selected stakeholders, and (7) evaluation of meeting outcomes. By conducting a feasibility study using the seven-step framework, the authors set the stage for conducting future compliance studies and enhancing the chance of a successful restoration.

  7. Composite veneering of complex amalgam restorations.

    Science.gov (United States)

    Demarco, Flávio Fernando; Zanchi, César Henrique; Bueno, Márcia; Piva, Evandro

    2007-01-01

    In large posterior cavities, indirect restorations could provide improved performance when compared to direct restorations, but with higher cost and removal of sound tooth structure. Improved mechanical properties have resulted in good clinical performance for amalgam in large cavities but without an esthetic appearance. Resin composites have become popular for posterior restorations, mainly because of good esthetic results. A restorative technique is presented that combines the esthetic properties of directly bonded resin composite and the wide range of indications for amalgam in stress-bearing areas.

  8. Clinical guidelines for indirect resin restorations.

    Science.gov (United States)

    Shannon, A

    1997-06-01

    Ongoing advances in adhesive dentistry have made it possible to successfully and predictably bond tooth-supporting restorations using conservative preparation techniques. Improvements in the durability and esthetic properties of tooth-colored restorative materials have also increased the range of available treatment options. However, dentists have been slow to accept both direct and indirect posterior esthetics. This article provides a step-by-step technique for practitioners who choose to treat their patients with indirect resin esthetic restorations. It will not discuss other posterior restorative treatment techniques or materials (i.e. gold, porcelain, amalgam, bonded amalgam, or direct resin).

  9. Esthetic restoration of discolored primary incisors.

    Science.gov (United States)

    Margolis, Fred S

    2005-01-01

    Restoring primary teeth can be a strenuous task for many dentists who would like to have an esthetic, easy-to-use and relatively quick restoration for children. But, the restoration of carious, fractured or discolored primary incisors gives the dentist the satisfaction of knowing that he/she has restored the smile and self-confidence of a growing child. This article describes a technique which is relatively easy and produces a beautiful outcome in a relatively short time. The author has used the technique in hundreds of children for over twenty-five years. Modifications in the technique have been made as newer materials and techniques have evolved.

  10. Governing Forest Landscape Restoration: Cases from Indonesia

    Directory of Open Access Journals (Sweden)

    Cora van Oosten

    2014-05-01

    Full Text Available Forest landscape restoration includes both the planning and implementation of measures to restore degraded forests within the perspective of the wider landscape. Governing forest landscape restoration requires fundamental considerations about the conceptualisation of forested landscapes and the types of restoration measures to be taken, and about who should be engaged in the governance process. A variety of governance approaches to forest landscape restoration exist, differing in both the nature of the object to be governed and the mode of governance. This paper analyses the nature and governance of restoration in three cases of forest landscape restoration in Indonesia. In each of these cases, both the original aim for restoration and the initiators of the process differ. The cases also differ in how deeply embedded they are in formal spatial planning mechanisms at the various political scales. Nonetheless, the cases show similar trends. All cases show a dynamic process of mobilising the landscape’s stakeholders, plus a flexible process of crafting institutional space for conflict management, negotiation and decision making at the landscape level. As a result, the landscape focus changed over time from reserved forests to forested mosaic lands. The cases illustrate that the governance of forest landscape restoration should not be based on strict design criteria, but rather on a flexible governance approach that stimulates the creation of novel public-private institutional arrangements at the landscape level.

  11. ECOLOGICAL RESTORATION:OUR HOPE FOR THE FUTURE?

    Institute of Scientific and Technical Information of China (English)

    WANG Xu-gao; LI Xiu-zhen; HE Hong S; HU Yuan-man

    2004-01-01

    Ecological restoration is widely employed from tens to millions of hectares in space, and from tens of days to thousands of years in time, which forces consideration of it thoroughly. We argue that three questions are the most important among the contents relevant of ecological restoration, including why, what and how to restore degraded systems. Why to restore determines whether or not the degraded ecological systems should be restored. What to restore is the goal of ecological restoration. The explicit goal of ecological restoration is necessary to guide ecological restoration workers in pursuit of excellence and prevent restoration from being swamped by purely technological activities. And how to restore means the methods and steps we should apply. To ensure the final success of ecological restoration, restored sites should be monitored and managed for long time to determine whether the selected methods are appropriate, and can be remedy better. Only to deal with these effectively, ecological restoration would be the hope for the future.

  12. Restoring the Pacific Northwest: the art and science of ecological restoration in Cascadia

    National Research Council Canada - National Science Library

    Apostol, D; Sinclair, M

    2006-01-01

    Restoring the Pacific Northwest is a handbook that brings together in a single volume a vast array of information on the science and practice of restoration in a broadly defined Pacific Northwest region...

  13. Dileptons and Chiral Symmetry Restoration

    CERN Document Server

    Hohler, P M

    2015-01-01

    We report on recent work relating the medium effects observed in dilepton spectra in heavy-ion collisions to potential signals of chiral symmetry restoration. The key connection remains the approach to spectral function degeneracy between the vector-isovector channel with its chiral partner, the axialvector-isovector channel. Several approaches are discussed to elaborate this connection, namely QCD and Weinberg sum rules with input for chiral order parameters from lattice QCD, and chiral hadronic theory to directly evaluate the medium effects of the axialvector channel and the pertinent pion decay constant as function of temperature. A pattern emerges where the chiral mass splitting between rho and a_1 burns off and is accompanied by a strong broadening of the spectral distributions.

  14. Anterior provisional restorations used to determine form, function, and esthetics for complex restorative situations, using all-ceramic restorative systems.

    Science.gov (United States)

    Reshad, Mamaly; Cascione, Domenico; Kim, Tae

    2010-02-01

    A technique is proposed for the restoration of a large and visible maxillary anterior defect. The importance of proper diagnosis, treatment planning, and communication is emphasized. Irreversible treatment should only be rendered once patient approval has been obtained through objective evaluation with provisional restorations. The techniques presented in this article use a combination of ceramic systems currently available to satisfy functional demands while achieving acceptable esthetics. A controlled series of steps, where the provisional restorative components are being replaced by the definitive ones is planned. The only difference between the provisional and definitive restorative components is the material used. The definitive restorations consisted of an implant-supported zirconium oxide framework. Individual pressed porcelain restorations were luted to the framework and a natural tooth. CLINICAL SIGNIFICANCE Provisional restorations allow an objective form of communication. Vertical and horizontal transitional lines can be effectively masked with appropriate treatment planning and a skilled ceramist. Many traditional dental laboratory steps may be eliminated or simplified without compromising the definitive restorations.

  15. International Documents on Landscape Restoration

    Directory of Open Access Journals (Sweden)

    Olga Pouperová

    2015-01-01

    Full Text Available In the theory and practice of cultural monuments protection, including garden art monuments and landscape protection, it has been often referred to international conventions and other international documents relating to this protection. Necessary condition for these documents to be adequately used in the practice is the precise understanding of their legal nature and a question arising therefrom, if and to what extent and to whom are those documents binding.The aim of this paper is to provide an analysis of the international documents relating to the landscape restoration. Following the analysis, the authors explore the scope and way of transposition of these documents and obligation arising therefrom into the Czech legal order. In the general part the authors analyse knowledge of the current jurisprudence on treaties and other international documents. They focus on the issue of the legal force of such documents, both on the international and national level. In the following part the authors deal with international documents on landscape restoration, explain legal nature of those documents and explicate whether the documents are formally legally binding or whether they may have other practical effects. The legally binding international treaties on the landscape protection include in particular the Convention on the Protection of the World Cultural and Natural Heritage (Paris, 1972 and the European Landscape Convention (Florence, 2000. As regard legally non-binding acts of international non-governmental organizations, the paper discusses the charters of the International Council on Monuments and Sites (ICOMOS, the Venice Charter of 1964 and the Florence Charter of 1981. Mentioned is also the Athens Charter (1933, respectively the New Athens Charter of 1998 dealing with the landscape in terms of the principles of urban planning.

  16. Optimal load shedding and restoration

    Science.gov (United States)

    Xu, Ding

    Load shedding is an emergency control action in power systems that can save systems from a wide-area blackout. Underfrequency load shedding, steady state load shedding, and voltage load shedding are widely used in power systems. These methods utilize either the steady state model or a simplified dynamic model to represent a power systems. In this dissertation, a general optimal load shedding method that considers both the dynamic process and load distribution is proposed. The unfavorable load shedding is then formulated as an optimization problem with the objective function of cost minimization. This objective function is subjected to system, security, and operation constraints. The entire problem becomes a question of optimization with differential and nonlinear equations as constraints. To solve this problem, discretization is used to change the differential equations into algebraic equations. The original problem is thus reformulated as an optimization problem and can be solved by a standard mathematical program. The general idea is then applied to traditional power systems, deregulated power systems, power systems with distributed generation, and load restoration. In the traditional power system, the method shows that governor action, generation dynamic, disturbance location, and economic factors can be taken into consideration. In the deregulated power system, two power market models are developed and incorporated into the load shedding scheme. In power systems with multiple distributed generations, the different cases of disturbances are analyzed and models of different distributed generation developed. The general idea is then applied. Finally, the load restoration problem is studied, and it is proposed that an optimization method be applied to it. This dissertation provides a comprehensive solution for load shedding problem in power systems. The models developed in this research can also be used to study other power system problems.

  17. Restored thermoluminescence in oxide crystals

    Energy Technology Data Exchange (ETDEWEB)

    Rakov, A.F., E-mail: afrakov@hotmail.co [Institute of Nuclear Physics, Uzbek Academy of Sciences, Tashkent, 700132 (Uzbekistan); Salikhbaev, U.S.; Islamov, A.K. [Institute of Nuclear Physics, Uzbek Academy of Sciences, Tashkent, 700132 (Uzbekistan); Bartram, R.H. [Department of Physics, University of Connecticut, Storrs, CT 06269-3046 (United States); Melcher, C.L. [Scintillation Materials Research Center, University of Tennessee, Knoxville, TN 37996-2000 (United States)

    2010-11-15

    In this paper, we present the results of a thermoluminescence study on several oxide crystals, including Y{sub 3}Al{sub 5}O{sub 12} (YAG), Y{sub 3}Al{sub 5}O{sub 12}:Nd (YAG:Nd), Lu{sub 2}SiO{sub 5}:Ce (LSO:Ce), Y{sub 2}SiO{sub 5}:Ce (YSO:Ce), Gd{sub 2}SiO{sub 5}:Ce (GSO:Ce), PbWO (PWO), and PbWO:La (PWO:La). A phenomenon involving restoration of thermoluminescence (TL) glow peaks is found to occur in some of the crystals investigated; crystals {gamma}-irradiated at room temperature and subsequently stored for some time in the dark at 77 K exhibit TL glow peaks in the range below room temperature. This phenomenon is caused not by a thermally or optically stimulated process, but rather as a by-product of a tunneling process. The intensity of the restored TL glow peaks measured in LSO:Ce crystals is found to be proportional both to the radiation dose and to the storage-time at low temperature. A phenomenological theoretical model is proposed, in which tunneling recombination occurs between deep electron and hole traps accompanied by the simultaneous ejection of an electron to the conduction band; some of these conduction electrons then repopulate shallow traps. An oxygen vacancy with two trapped electrons is assumed to be the deep electron trap in this model. The role of oxygen vacancies is confirmed by heating in air at 1000 {sup o}C. This model is applied specifically to LSO:Ce, and several possible candidates are suggested for shallow traps in that material.

  18. An information theory of image gathering

    Science.gov (United States)

    Fales, Carl L.; Huck, Friedrich O.

    1991-01-01

    Shannon's mathematical theory of communication is extended to image gathering. Expressions are obtained for the total information that is received with a single image-gathering channel and with parallel channels. It is concluded that the aliased signal components carry information even though these components interfere with the within-passband components in conventional image gathering and restoration, thereby degrading the fidelity and visual quality of the restored image. An examination of the expression for minimum mean-square-error, or Wiener-matrix, restoration from parallel image-gathering channels reveals a method for unscrambling the within-passband and aliased signal components to restore spatial frequencies beyond the sampling passband out to the spatial frequency response cutoff of the optical aperture.

  19. Finite element analysis of multi-piece post-crown restoration using different types of adhesives

    Institute of Scientific and Technical Information of China (English)

    Lin-Wei Lu; Guang-Wei Meng; Zhi-Hui Liu

    2013-01-01

    The multi-piece post-crown technique is more effective in restoring residual root than other restoration techniques. Various types of adhesives have different material properties that affect restoration. Therefore, the choice of adhesive is particularly important for patients. However, the effect of different kinds of adhesives was not too precise by experimental methods when concerning about individual differences of teeth. One tooth root can only be restored with one type of adhesive in experiment. After the mechanical test, this tooth root cannot be restored with other adhesives. With the help of medical imaging technology, reverse engineering and finite element analysis, a molar model can be reconstructed precisely and restored using different types of adhesives. The same occlusal and chewing loads were exerted on the same restored residual root models with different types of adhesives separately. Results of von Mises stress analysis showed that the adhesives with low Young’s modulus can protect the root canal effectively. However, a root canal concentration is apparently produced around the root canal orifice when chewing. Adhesives with large Young’s modulus can buffer the stress concentration of the root canal orifice. However, the root canal tissue may be destroyed because the adhesive is too hard to buffer the load.

  20. Biomedical image understanding methods and applications

    CERN Document Server

    Lim, Joo-Hwee; Xiong, Wei

    2015-01-01

    A comprehensive guide to understanding and interpreting digital images in medical and functional applications Biomedical Image Understanding focuses on image understanding and semantic interpretation, with clear introductions to related concepts, in-depth theoretical analysis, and detailed descriptions of important biomedical applications. It covers image processing, image filtering, enhancement, de-noising, restoration, and reconstruction; image segmentation and feature extraction; registration; clustering, pattern classification, and data fusion. With contributions from ex

  1. IMAGES, IMAGES, IMAGES

    Energy Technology Data Exchange (ETDEWEB)

    Marcus, A.

    1980-07-01

    The role of images of information (charts, diagrams, maps, and symbols) for effective presentation of facts and concepts is expanding dramatically because of advances in computer graphics technology, increasingly hetero-lingual, hetero-cultural world target populations of information providers, the urgent need to convey more efficiently vast amounts of information, the broadening population of (non-expert) computer users, the decrease of available time for reading texts and for decision making, and the general level of literacy. A coalition of visual performance experts, human engineering specialists, computer scientists, and graphic designers/artists is required to resolve human factors aspects of images of information. The need for, nature of, and benefits of interdisciplinary effort are discussed. The results of an interdisciplinary collaboration are demonstrated in a product for visualizing complex information about global energy interdependence. An invited panel will respond to the presentation.

  2. Survival of ART restorations assessed using selected FDI and modified ART restoration criteria

    NARCIS (Netherlands)

    Farag, A.; Sanden, W.J.M. van der; Abdelwahab, H.; Frencken, J.E.F.M.

    2011-01-01

    A new set of criteria for assessing the quality of restorations using modern restorative materials, named FDI criteria, was recently introduced. This study tested the null hypothesis that there is no significant difference in survival estimate percentages of ART restorations assessed using selected

  3. 75 FR 32877 - Financial Assistance: Wildlife Restoration, Sport Fish Restoration, Hunter Education and Safety

    Science.gov (United States)

    2010-06-10

    ... Wildlife and Sport Fish Restoration Programs Improvement Act of 2000. Section 80.61 What requirements apply... the Dingell-Johnson Sport Fish Restoration Act, but the current regulations apply the requirement to... Dingell-Johnson Sport Fish Restoration Act. This would help agencies comply with statutory requirements...

  4. Combination Restoration for Motion-blurred Color Videos under Limited Transmission Bandwidth

    Directory of Open Access Journals (Sweden)

    Shi Li

    2009-10-01

    Full Text Available Color video images degraded in a deterministic way by motion-blurring can be restored by the new algorithm in real-time by using color components combination to fit to the limited transmission bandwidth. The image motion PSF of each surface of YUV422 image can be obtained based on the color space conversion model. The Y, U, V planes are packed to construct a 2 dimensional complex array. Through the decomposition of frequency domain, the Y, U, V frequency can be had respectively by performing Fourier transform a time on the specific complex array. The resulting frequencies will be filtered by Wiener filter to generate the final restored images. The proposed algorithm can restore 1024x1024 24-bit motionblurred color video images at 18 ms/frame speed on GPU, and the PSNR of the restored frame is 31.45. The experiment results show that the proposed algorithm is 3X speed compared to the traditional algorithm, and it reduces the bandwidth of video data stream 1/3.

  5. Detection of Carious Lesions and Restorations Using Particle Swarm Optimization Algorithm.

    Science.gov (United States)

    Naebi, Mohammad; Saberi, Eshaghali; Risbaf Fakour, Sirous; Naebi, Ahmad; Hosseini Tabatabaei, Somayeh; Ansari Moghadam, Somayeh; Bozorgmehr, Elham; Davtalab Behnam, Nasim; Azimi, Hamidreza

    2016-01-01

    Background/Purpose. In terms of the detection of tooth diagnosis, no intelligent detection has been done up till now. Dentists just look at images and then they can detect the diagnosis position in tooth based on their experiences. Using new technologies, scientists will implement detection and repair of tooth diagnosis intelligently. In this paper, we have introduced one intelligent method for detection using particle swarm optimization (PSO) and our mathematical formulation. This method was applied to 2D special images. Using developing of our method, we can detect tooth diagnosis for all of 2D and 3D images. Materials and Methods. In recent years, it is possible to implement intelligent processing of images by high efficiency optimization algorithms in many applications especially for detection of dental caries and restoration without human intervention. In the present work, we explain PSO algorithm with our detection formula for detection of dental caries and restoration. Also image processing helped us to implement our method. And to do so, pictures taken by digital radiography systems of tooth are used. Results and Conclusion. We implement some mathematics formula for fitness of PSO. Our results show that this method can detect dental caries and restoration in digital radiography pictures with the good convergence. In fact, the error rate of this method was 8%, so that it can be implemented for detection of dental caries and restoration. Using some parameters, it is possible that the error rate can be even reduced below 0.5%.

  6. Detection of Carious Lesions and Restorations Using Particle Swarm Optimization Algorithm

    Directory of Open Access Journals (Sweden)

    Mohammad Naebi

    2016-01-01

    Full Text Available Background/Purpose. In terms of the detection of tooth diagnosis, no intelligent detection has been done up till now. Dentists just look at images and then they can detect the diagnosis position in tooth based on their experiences. Using new technologies, scientists will implement detection and repair of tooth diagnosis intelligently. In this paper, we have introduced one intelligent method for detection using particle swarm optimization (PSO and our mathematical formulation. This method was applied to 2D special images. Using developing of our method, we can detect tooth diagnosis for all of 2D and 3D images. Materials and Methods. In recent years, it is possible to implement intelligent processing of images by high efficiency optimization algorithms in many applications especially for detection of dental caries and restoration without human intervention. In the present work, we explain PSO algorithm with our detection formula for detection of dental caries and restoration. Also image processing helped us to implement our method. And to do so, pictures taken by digital radiography systems of tooth are used. Results and Conclusion. We implement some mathematics formula for fitness of PSO. Our results show that this method can detect dental caries and restoration in digital radiography pictures with the good convergence. In fact, the error rate of this method was 8%, so that it can be implemented for detection of dental caries and restoration. Using some parameters, it is possible that the error rate can be even reduced below 0.5%.

  7. In vitro evaluation of a silica whitening toothpaste containing blue covarine on the colour of teeth containing anterior restoration materials.

    Science.gov (United States)

    Philpotts, Carole J; Cariddi, Eufemia; Spradbery, Paul S; Joiner, Andrew

    2017-08-18

    To investigate the effects of a silica-based whitening toothpaste containing blue covarine on the colour of restorations in extracted human teeth. Human extracted teeth were mounted in acrylic resin. A cavity was cut into the enamel surface and the specimen restored with either glass ionomer or composite dental materials. Following 4 weeks storage in water, specimens were treated with either water, red wine or a toothpaste containing blue covarine (n=10) for 24h followed by brushing with a silica-based toothpaste. Specimens were imaged with a digital imaging system at baseline, after 24h treatment and after brushing with a silica-based toothpaste. CIELAB colour parameters were determined for the restoration and the whole specimen and overall mean colour changes calculated (ΔE). Baseline and post-brushing images were compared subjectively for overall stain and staining around the restoration margin. Red wine produced the largest ΔE values for whole specimens and for all restoration materials and the largest subjective stain scores for whole specimens and restoration margins. The red wine stain was not completely removed by brushing with a silica-based toothpaste. Comparisons of the red wine group with either the blue covarine toothpaste group or the water group were of statistical significance for all parameters (ANOVA, Tukey-Kramer, p0.05) to the water group, for all restoration material types. Exaggerated treatment with a blue covarine containing toothpaste does not significantly affect the colour of the restoration or the restoration margin of the dental materials tested versus a water alone treatment. The silica-based blue covarine containing toothpaste does not permanently stain the restorative materials tested or their margins. Copyright © 2017. Published by Elsevier Ltd.

  8. Restoration of the endodontically treated posterior tooth

    Directory of Open Access Journals (Sweden)

    Andrea Polesel

    2014-06-01

    Results and conclusions: Direct adhesive restorations, indirect bonded restorations and traditional full crown are three therapeutic options for the single posterior endodontically treated teeth. The amount of remaining sound tooth structure is the most significant factor influencing the therapeutic approach. The clinician's operative skill is a determining aspect for long-term success of adhesive inlays.

  9. Changing trends in hair restoration surgery

    Directory of Open Access Journals (Sweden)

    Venkataram Mysore

    2006-01-01

    Full Text Available Androgenetic alopecia is an important and common cause for baldness. Despite recent advances, the drug therapy of this condition remains unsatisfactory. Surgical hair restoration is the only permanent method of treating this condition. Introduction of recent techniques such as follicular unit transplantation have improved the cosmetic results and patient satisfaction. This article discusses the latest trends in hair restoration surgery.

  10. Restoration of traumatized teeth with resin composites

    DEFF Research Database (Denmark)

    Pallesen, Ulla; van Dijken, Jan WV

    2017-01-01

    For a long time, the primary choice for initial restoration of a crown-fractured front tooth has been resin composite material. The restoration can in most cases be performed immediately after injury if there is no sign of periodontal injury. The method’s adhesive character is conservative to tooth...

  11. Wetland restoration, flood pulsing, and disturbance dynamics

    Science.gov (United States)

    Middleton, Beth A.

    1999-01-01

    While it is generally accepted that flood pulsing and disturbance dynamics are critical to wetland viability, there is as yet no consensus among those responsible for wetland restoration about how best to plan for those phenomena or even whether it is really necessary to do so at all. In this groundbreaking book, Dr. Beth Middleton draws upon the latest research from around the world to build a strong case for making flood pulsing and disturbance dynamics integral to the wetland restoration planning process.While the initial chapters of the book are devoted to laying the conceptual foundations, most of the coverage is concerned with demonstrating the practical implications for wetland restoration and management of the latest ecological theory and research. It includes a fascinating case history section in which Dr. Middleton explores the restoration models used in five major North American, European, Australian, African, and Asian wetland projects, and analyzes their relative success from the perspective of flood pulsing and disturbance dynamics planning.Wetland Restoration also features a wealth of practical information useful to all those involved in wetland restoration and management, including: * A compendium of water level tolerances, seed germination, seedling recruitment, adult survival rates, and other key traits of wetland plant species * A bibliography of 1,200 articles and monographs covering all aspects of wetland restoration * A comprehensive directory of wetland restoration ftp sites worldwide * An extensive glossary of essential terms

  12. Extended Resin Composite Restorations: Techniques and Procedures

    NARCIS (Netherlands)

    Loomans, B.A.C.; Hilton, T.

    2016-01-01

    This article gives an overview of the state of the art of different restorative treatment procedures and techniques needed for placing extended posterior resin composite restorations. Clinical aspects related to the procedure are discussed and reviewed based on the current literature, such as the

  13. Restoration of missing or misplaced canines.

    Science.gov (United States)

    Bower, C F; Reinhardt, R A

    1985-06-01

    Restorative treatments for canines were discussed to correct three clinical abnormalities: (1) fully erupted permanent canine in the lateral incisor position, (2) missing permanent canines, and (3) partially exposed canines in normal arch position. The primary concerns are the development of esthetics, anterior guidance, and adequate support for fixed restorations.

  14. Restoration of a fractured primary incisor.

    Science.gov (United States)

    Romero, M; Saez, M; Cabrerizo, C

    2001-01-01

    Esthetic restoration on primary teeth has been a special challenge to pediatric dentists. Composite restorations are the most often used treatment for decay and fractures of primary teeth, however, there are other possible alternatives. We present a case in which we have used an acrylic crown to treat a fractured primary incisor in a 1.8 years old child.

  15. Restoring primary anterior teeth: updated for 2014.

    Science.gov (United States)

    Waggoner, William F

    2015-01-01

    The purpose of this paper was to review the current literature associated with the techniques and materials for the restoration of primary anterior teeth and make clinical recommendations based upon the available literature. A variety of esthetic restorative materials are available to utilize for restoring primary incisors. Awareness of the specific strengths, weakness, and properties of each material can enhance the clinician's ability to make the best choice of selection for each individual situation. Intracoronal restorations of primary teeth may utilize resin composites, glass ionomer cements, resin-modified ionomers, or polyacid-modified resins. Full coronal restoration of primary incisors may be indicated for a number of reasons. Crowns available for restoration of primary incisors include those that are directly bonded onto the tooth, which generally are a resin material, and crowns that are luted onto the tooth and are either some type of stainless steel or zirconia crown. There is insufficient controlled, clinical data to suggest that one type of restoration is superior to another. Operator preferences, esthetic demands by parents, the child's behavior, the amount of tooth structure remaining, and moisture and hemorrhage control are all variables that affect the decision and ultimate outcome of whatever restorative solution is chosen.

  16. Mechanical site preparation for forest restoration

    Science.gov (United States)

    Magnus Lof; Daniel C. Dey; Rafael M. Navarro; Douglass F. Jacobs

    2012-01-01

    Forest restoration projects have become increasingly common around the world and planting trees is almost always a key component. Low seedling survival and growth may result in restoration failures and various mechanical site preparation techniques for treatment of soils and vegetation are important tools used to help counteract this. In this article, we synthesize the...

  17. The Teacher's Guide to Restorative Classroom Discipline

    Science.gov (United States)

    Meyer, Luanna H.; Evans, Ian M.

    2012-01-01

    With restorative discipline, schools move beyond punitive approaches to shared expectations for learning and behavior. Used together with "The School Leader's Guide to Restorative Discipline," this teacher's guide shows how to create a welcoming and responsible community within your classroom, contributing to a consistent, schoolwide approach to…

  18. 76 FR 47055 - Emergency Restoration Plan (ERP)

    Science.gov (United States)

    2011-08-04

    ... 7 CFR Part 1730 RIN 0572-AC16 Emergency Restoration Plan (ERP) AGENCY: Rural Utilities Service, USDA... maintain an Emergency Response Plan (ERP) that details how the borrower will restore its system in the... ERP requirement was not entirely new to the borrowers, as RUS had recommended similar ``plans'' in...

  19. A study of composite restorations as a tool in forensic identification

    Directory of Open Access Journals (Sweden)

    Bahavathi Ananthan Hemasathya

    2013-01-01

    Full Text Available Introduction: Comparing ante-mortem and post-mortem dental data is a principal method of identification in forensic odontology. Radiographic images of amalgam have been used in dental forensics for identification due to their unique appearance. Aim: The aim of this study was to investigate whether radio-opaque composite restorations have a potential for identification in forensic odontology. Materials and Methods: Thirty typodont mandibular first molar teeth were prepared with Class-II (proximo-occlusal cavities and restored with a radio-opaque composite (Tetric N-Ceram. Two sets of standardized radiographs were taken from the 30 teeth, keeping the radiological parameters constant. One set of these 30 radiographs was named as SET 1. Ten randomly chosen radiographs from the other set and two other radiographs of Class-II composite restorations in typodont teeth constituted SET 2. Thirty dentally trained examiners were asked to match the 12 radiographic images of SET 2 with those of SET 1. Results: The results show that 15 examiners were able to correctly match all the 12 images. Statistical analysis was done using kappa statistical test. Conclusion: This study shows that, if the post-mortem radiographs are accurate duplicates of ante-mortem radiographs of composite restorations, then the shape of the composite restoration is unique and can be used for identification.

  20. G-Channel Restoration for RWB CFA with Double-Exposed W Channel

    Directory of Open Access Journals (Sweden)

    Chulhee Park

    2017-02-01

    Full Text Available In this paper, we propose a green (G-channel restoration for a red–white–blue (RWB color filter array (CFA image sensor using the dual sampling technique. By using white (W pixels instead of G pixels, the RWB CFA provides high-sensitivity imaging and an improved signal-to-noise ratio compared to the Bayer CFA. However, owing to this high sensitivity, the W pixel values become rapidly over-saturated before the red–blue (RB pixel values reach the appropriate levels. Because the missing G color information included in the W channel cannot be restored with a saturated W, multiple captures with dual sampling are necessary to solve this early W-pixel saturation problem. Each W pixel has a different exposure time when compared to those of the R and B pixels, because the W pixels are double-exposed. Therefore, a RWB-to-RGB color conversion method is required in order to restore the G color information, using a double-exposed W channel. The proposed G-channel restoration algorithm restores G color information from the W channel by considering the energy difference caused by the different exposure times. Using the proposed method, the RGB full-color image can be obtained while maintaining the high-sensitivity characteristic of the W pixels.

  1. G-Channel Restoration for RWB CFA with Double-Exposed W Channel.

    Science.gov (United States)

    Park, Chulhee; Song, Ki Sun; Kang, Moon Gi

    2017-02-05

    In this paper, we propose a green (G)-channel restoration for a red-white-blue (RWB) color filter array (CFA) image sensor using the dual sampling technique. By using white (W) pixels instead of G pixels, the RWB CFA provides high-sensitivity imaging and an improved signal-to-noise ratio compared to the Bayer CFA. However, owing to this high sensitivity, the W pixel values become rapidly over-saturated before the red-blue (RB) pixel values reach the appropriate levels. Because the missing G color information included in the W channel cannot be restored with a saturated W, multiple captures with dual sampling are necessary to solve this early W-pixel saturation problem. Each W pixel has a different exposure time when compared to those of the R and B pixels, because the W pixels are double-exposed. Therefore, a RWB-to-RGB color conversion method is required in order to restore the G color information, using a double-exposed W channel. The proposed G-channel restoration algorithm restores G color information from the W channel by considering the energy difference caused by the different exposure times. Using the proposed method, the RGB full-color image can be obtained while maintaining the high-sensitivity characteristic of the W pixels.

  2. Techniques of forest restoration in restingas

    Directory of Open Access Journals (Sweden)

    Liliane Garcia da Silva Morais Rodrigues

    2016-03-01

    Full Text Available Restinga is an ecosystem of the Atlantic Forest Biome vegetation which has ecological functions and is undergoing anthropogenic occupations that result in the disturbance and its suppression of these environments. But to be the restoration of degraded restinga is necessary to know the different formations of the ecosystem and their respective characteristics. From this diagnosis, one can choose the most appropriate techniques to apply for its restoration. Thus, this study aims to conduct a literature on restoration techniques in restinga environments. It was found that forest restoration on restinga, in most cases there is use of natural regeneration techniques nucleation, and these studies highlight the successional advances and establishments of life forms preserved features of the area, thus making the restoration in these environments.

  3. Infrastructure system restoration planning using evolutionary algorithms

    Science.gov (United States)

    Corns, Steven; Long, Suzanna K.; Shoberg, Thomas G.

    2016-01-01

    This paper presents an evolutionary algorithm to address restoration issues for supply chain interdependent critical infrastructure. Rapid restoration of infrastructure after a large-scale disaster is necessary to sustaining a nation's economy and security, but such long-term restoration has not been investigated as thoroughly as initial rescue and recovery efforts. A model of the Greater Saint Louis Missouri area was created and a disaster scenario simulated. An evolutionary algorithm is used to determine the order in which the bridges should be repaired based on indirect costs. Solutions were evaluated based on the reduction of indirect costs and the restoration of transportation capacity. When compared to a greedy algorithm, the evolutionary algorithm solution reduced indirect costs by approximately 12.4% by restoring automotive travel routes for workers and re-establishing the flow of commodities across the three rivers in the Saint Louis area.

  4. [Esthetic restorations of primary anterior teeth].

    Science.gov (United States)

    Elqadir, A Jamil; Shapira, J; Ziskind, K; Ram, D

    2013-04-01

    Esthetic treatment of primary teeth is one of the greatest challenges to pediatric dentists. A variety of restorative options using full coverage are available for anterior primary teeth. In the last half century the emphasis on treatment of severely decayed primary teeth shifted from extraction to restoration. In the past, restorations consisted of placement of stainless steel crowns on severely decayed teeth. However, they are esthetically unacceptable today. Over the last decade parents expect a higher esthetic standard for their children's primary teeth. Thus, the restoration should provide esthetic appearance and durability in addition to restoring function. The purpose of this review is to describe the types of full coverage options for anterior primary teeth currently available.

  5. Crown lengthening surgery: a restorative-driven periodontal procedure.

    Science.gov (United States)

    Levine, D F; Handelsman, M; Ravon, N A

    1999-02-01

    Improper management of the periodontal tissues during restorative procedures is a common, but often overlooked, cause of failure. When a restoration is placed, the preservation of an intact, healthy periodontium is necessary to maintain the tooth or teeth being restored. Predictable long-term restorative success requires a combination of restorative principles with the correct management of the periodontal tissues.

  6. Fracture Resistance and Failure Mode of Endodontically Treated Premolars Restored with Different Adhesive Restorations

    Directory of Open Access Journals (Sweden)

    Nasrin Sarabi

    2015-03-01

    Full Text Available Introduction: The restoration of endodontically treated teeth is a topic that has been studied extensively but it is still a challenge for dental practitioners. The aim of this study was to evaluate fracture resistance, fracture patterns and fracture location of endodontically treated human maxillary premolars restored with direct and indirect composite resin and ceramic restoration. Methods: Eighty non-carious maxillary premolars were selected and divided into four groups (n=20. Endodontic treatment and mesio-occluso-distal preparations were carried out in all the groups except for the control group (group I. Subsequently, the prepared teeth were restored as follows: group II: indirect composite restoration; group III: ceramic restoration; group IV: direct composite restoration. The specimens were subjected to compressive axial loading until fracture occurred. The mode of failure was also recorded. Results: Group I had higher fracture resistance (1196.82±241.74 than the other groups (P

  7. Restorative justice and the active victim: Exploring the concept of empowerment

    Directory of Open Access Journals (Sweden)

    Aertsen Ivo

    2011-01-01

    Full Text Available This paper departs from the observation that the victim image leading public discourse has transformed in recent years: increasingly victims reject the traditional victim label implying helplessness and dependency to adopt the image of the emancipated victim that wishes to participate in the criminal proceedings. Restorative justice at first sight provides an answer to these emancipated victims’ wishes, offering them participation in criminal proceedings. Yet, using the concept of empowerment as an example and the community psychology perspective as a theoretical reference, our analysis suggests that restorative justice uses a restricted definition of empowerment: it reduces empowerment to developing self-confidence and new understandings of the offence, neglecting the behavioural component of empowerment. This characteristic of restorative justice seems to deny victims’ capacities to promote social change and inhibit them from reaching true empowerment.

  8. Spatial Autoregressions in Digital Image Restoration: Simultaneous Models.

    Science.gov (United States)

    1980-12-01

    using the torus assumption and also by Fourier inversion of the spectral density function corresponding to some SAR models without the torus...the eigenvalues of the covariance matrix are the two-dimensional discrete spectral density function . We have also estimated the parameters of the... density function (SDF). In practice it is not known. Hence, the true SDF is replaced by an estimate. Typical estimates of the SDF can be obtained by

  9. Mixed Gaussian-Impulse Noise Image Restoration Via Total Variation

    Science.gov (United States)

    2012-05-01

    pp. 402–407. [12] L. Rudin , S. Osher, and E. Fatemi, “Nonlinear total vari- ation based noise removal algorithms.,” Physica D. Non- lin. Phenomena...variation regularization in positron emission tomography,” UCLA CAM Report 98-48, 1998, CAM Report 98-48, UCLA. [16] S. Osher, N. Paragios, L. Rudin , and P

  10. Investigation on basic methods for digital image restoration

    OpenAIRE

    BALLESTER ROMANIV, OLGA

    2015-01-01

    El siguiente documento, tras la presentación del trabajo y las motivaciones que llevan a escribirlo, va a tratar sobre el tratamiento digital de imagen y sus aplicaciones, focalizándose en la degradación y restauración de dichas imágenes. En primer lugar se explicará el filtrado espacial y frecuencial, para familiarizar al lector con dichos términos ya que serán de gran importancia en el desarrollo posterior. Una vez sentadas las bases se tratará el ruido, tanto con ruido Gauss...

  11. Nonlinear Image Restoration in Confocal Microscopy : Stability under Noise

    NARCIS (Netherlands)

    Roerdink, J.B.T.M.

    1995-01-01

    In this paper we study the noise stability of iterative algorithms developed for attenuation correction in Fluorescence Confocal Microscopy using FT methods. In each iteration the convolution of the previous estimate is computed. It turns out that the estimators are robust to noise perturbation.

  12. Nonlinear Image Restoration in Confocal Microscopy : Stability under Noise

    NARCIS (Netherlands)

    Roerdink, J.B.T.M.

    1995-01-01

    In this paper we study the noise stability of iterative algorithms developed for attenuation correction in Fluorescence Confocal Microscopy using FT methods. In each iteration the convolution of the previous estimate is computed. It turns out that the estimators are robust to noise perturbation.

  13. Biomechanical demands on posterior fusion instrumentation during lordosis restoration procedures.

    Science.gov (United States)

    Kuo, Calvin C; Martin, Audrey; Telles, Connor; Leasure, Jeremi; Iezza, Alex; Ames, Christopher; Kondrashov, Dimitriy

    2016-09-01

    OBJECTIVE The goal of this study was to investigate the forces placed on posterior fusion instrumentation by 3 commonly used intraoperative techniques to restore lumbar lordosis: 1) cantilever bending; 2) in situ bending; and 3) compression and/or distraction of screws along posterior fusion rods. METHODS Five cadaveric torsos were instrumented with pedicle screws at the L1-5 levels. Specimens underwent each of the 3 lordosis restoration procedures. The pedicle screw pullout force was monitored in real time via strain gauges that were mounted unilaterally at each level. The degree of correction was noted through fluoroscopic imaging. The peak loads experienced on the screws during surgery, total demand on instrumentation, and resting loads after corrective maneuvers were measured. RESULTS A mean overall lordotic correction of 10.9 ± 4.7° was achieved. No statistically significant difference in lordotic correction was observed between restoration procedures. In situ bending imparted the largest loads intraoperatively with an average of 1060 ± 599.9 N, followed by compression/distraction (971 ± 534.1 N) and cantilever bending (705 ± 413.0 N). In situ bending produced the largest total demand and postoperative loads at L-1 (1879 ± 1064.1 and 487 ± 118.8 N, respectively), which were statistically higher than cantilever bending and compression/distraction (786 ± 272.1 and 138 ± 99.2 N, respectively). CONCLUSIONS In situ bending resulted in the highest mechanical demand on posterior lumbar instrumentation, as well as the largest postoperative loads at L-1. These results suggest that the forces generated with in situ bending indicate a greater chance of intraoperative instrumentation failure and postoperative proximal pedicle screw pullout when compared with cantilever bending and/or compression/distraction options. The results are aimed at optimizing correction and fusion strategies in lordosis restoration cases.

  14. Hydrological classification, a practical tool for mangrove restoration

    NARCIS (Netherlands)

    Loon, van Anne F.; Brake, te Bram; Huijgevoort, Van Marjolein H.J.; Dijksma, Roel

    2016-01-01

    Mangrove restoration projects, aimed at restoring important values of mangrove forests after degradation, often fail because hydrological conditions are disregarded. We present a simple, but robust methodology to determine hydrological suitability for mangrove species, which can guide restoration

  15. RESTORATION INDUCED BY CATALASE IN IRRADIATED MICROORGANISMS

    Science.gov (United States)

    Latarjet, Raymond; Caldas, Luis Renato

    1952-01-01

    1. E. coli, strain K-12, and B. megatherium 899, irradiated in strict but still undefined physiological conditions with certain heavy doses of ultraviolet light, are efficiently restored by catalase, which acts on or fixes itself upon the bacteria in a few minutes. This restoration (C. R.), different from photorestoration, is aided by a little visible light. 2. At 37° the restorability lasts for about 2 hours after UV irradiation; the restored cells begin to divide at the same time as the normal survivors. 3. C. R. is not produced after x-irradiation. 4. B. megatherium Mox and E. coli, strain B/r show little C. R.; E. coli strain B shows none. None of these three strains is lysogenic, whereas the two preceding catalase-restorable strains are. 5. Phage production in the system "K-12 infected with T2 phage" is restored by catalase after UV irradiation, whereas phage production in the system "infected B" is not. 6. With K-12, catalase does not prevent the growth of phage and the lysis induced by UV irradiation (Lwoff's phenomenon). 7. Hypotheses are discussed concerning: (a) the chemical nature of this action of catalase; (b) a possible relation between C. R. and lysogenicity of the sensitive bacteria; (c) the consequences of such chemical restorations on the general problem of cell radiosensitivity. PMID:14898028

  16. Atraumatic restorative treatment in atypical cavities

    Directory of Open Access Journals (Sweden)

    Letícia Simino Carvalho

    2009-10-01

    Full Text Available The atraumatic restorative treatment has been widely divulged among professionals in the area of Pediatric Dentistry. This restorative technique is included in the philosophy of Minimal Intervention and is considered one of the most conservative treatments, because only the layer of infected dentin caries is removed. Moreover, the atraumatic restorative treatment has been shown to be less painful than conventional approaches, and local anesthesia is rarely required. After the removal of the infected dentin, the cavities are filled with glass ionomer cement, a material that has antimicrobial capacity, good marginal sealing and constant fluorine release and recharge. In spite of the increasing number of studies about atraumatic restorative treatment, only studies related to restorations in occlusal cavities have shown scientific evidences about the technique. The aim of this study was to evaluate the feasibility of atraumatic restorative treatment in cavities with 3 or more surfaces involved, by means of a clinical case report of a patient with extensive dstruction in primary teeth, who was submitted to atraumatic restorative treatment, and observe the result of the treatment after one year of clinical and radiographic control.

  17. Digital imaging and fabrication.

    Science.gov (United States)

    Zandparsa, Roya

    2014-01-01

    Bioceramics have been adopted in dental restorations for implants, bridges, inlays, onlays, and all-ceramic crowns. Dental bioceramics include glass ceramics, reinforced porcelains, zirconias, aluminas, fiber-reinforced ceramic composites, and multilayered ceramic structures. The process of additive manufacturing is ideally suited to dentistry. Models are designed using data from a computed tomography scan or magnetic resonance imaging. Since its development in 2001, direct ceramic machining of presintered yttria tetragonal zirconia polycrystal has become increasingly popular in dentistry. There are wide variety commercially available cements for luting all-ceramic restorations. However, resin cements have lower solubility and better aesthetic characteristics.

  18. STN-stimulation in Parkinson's disease restores striatal inhibition of thalamocortical projection

    DEFF Research Database (Denmark)

    Geday, Jacob; Østergaard, Karen; Johnsen, Erik;

    2009-01-01

    To test the hypothesis that deep brain stimulation of the subthalamic nucleus (STN) restores the inhibitory output to the striatothalamocortical loop in Parkinson's disease, we obtained functional brain images of blood flow in 10 STN-stimulated patients with Parkinson's disease. Patients were...

  19. Assessing ex vivo dental biofilms and in vivo composite restorations using cross-polarization optical coherence tomography

    Science.gov (United States)

    Jones, R.; Aparicio, C.; Chityala, R.; Chen, R.; Fok, A.; Rudney, J.

    2012-01-01

    A cross-polarization 1310-nm optical coherence tomography system (CP-OCT), using a beam splitter based design, was used to assess ex vivo growth of complex multi-species dental biofilms. These biofilm microcosms were derived from plaque samples along the interface of composite or amalgam restoration in children with a history of early childhood caries. This paper presents a method of measuring the mean biofilm height of mature biofilms using CP-OCT. For our in vivo application, the novel swept source based CP-OCT intraoral probe (Santec Co. Komaki, Japan) dimensions and system image acquisition speed (20 image frames/second) allowed imaging pediatric subjects as young as 4 years old. The subsurface enamel under the interface of composite resin restorations of pediatric subjects were imaged using CP-OCT. Cavitated secondary caries is clearly evident from sound resin composite restorations.

  20. Development of Restorative Justice in China: Theory and Practice

    OpenAIRE

    Yinzhi Shen

    2016-01-01

    Restorative justice has become a global social movement for criminal justice reform, with over eighty countries adopting some form of restorative justice program to tackle their crime problems. The theory of restorative justice was introduced to the Chinese academia in 2002. So far, various restorative justice programs have been developed in China. This paper aims to systematically review the development of restorative justice in China by analyzing academic literature on restorative justice a...

  1. Postoperative sensitivity in class I composite resin restorations in vivo

    OpenAIRE

    Casselli, DSM; Martins, LRM

    2006-01-01

    Purpose: This study evaluated the postoperative sensitivity of posterior Class I composite resin restorations, restored with a self-etching or a total-etch one-bottle adhesive system. Materials and Methods: One hundred four restorations were replaced by one clinician in 52 patients. Each patient received two restorations. After cavity preparations were completed under rubber-dam isolation, they were restored using Clearfil SE Bond or Single Bond and a resin-based restorative material (Filtek ...

  2. Maximum entropy signal restoration with linear programming

    Energy Technology Data Exchange (ETDEWEB)

    Mastin, G.A.; Hanson, R.J.

    1988-05-01

    Dantzig's bounded-variable method is used to express the maximum entropy restoration problem as a linear programming problem. This is done by approximating the nonlinear objective function with piecewise linear segments, then bounding the variables as a function of the number of segments used. The use of a linear programming approach allows equality constraints found in the traditional Lagrange multiplier method to be relaxed. A robust revised simplex algorithm is used to implement the restoration. Experimental results from 128- and 512-point signal restorations are presented.

  3. Conservation, management, and restoration of coral reefs.

    Science.gov (United States)

    Chavanich, Suchana; Soong, Keryea; Zvuloni, Assaf; Rinkevich, Baruch; Alino, Porfirio

    2015-04-01

    The 8th International Conference on Coelenterate Biology (ICCB 8) was held in Eilat, Israel from December 1st to 5th 2013. The conference included 15 sessions, one of which discussed the latest information on the conservation, management, and restoration of Coelenterata in different parts of the world. A total of 16 oral presentations and 5 posters were presented in this session. Of these 21 papers, 11 were related to conservation issues, 7 described management, and 3 discussed restoration. This session provided insights on the current conservation, management, and restoration of coelenterates in different parts of the world.

  4. Current Concepts in Restorative Implant Dentistry

    Institute of Scientific and Technical Information of China (English)

    Prof.Marchack

    2009-01-01

    Patients today are incteasingly aware of dental implants.and their expectations are for esthetically and functionally pleasingimplant restorations that mimic natural teeth.This presentation will give both the experienced and novice practitioner a better understand-ing of how restorative implant dentistry has evolved.Treatment planning and restorative options for single implants.multiple implants andfully edentulons arches will be discussed,and the use of modern materials and CADCAM technology in fabricating the most contemporaryfixed implant supported prostheses will be demonstrated.

  5. Dopamine restores reward prediction errors in old age.

    Science.gov (United States)

    Chowdhury, Rumana; Guitart-Masip, Marc; Lambert, Christian; Dayan, Peter; Huys, Quentin; Düzel, Emrah; Dolan, Raymond J

    2013-05-01

    Senescence affects the ability to utilize information about the likelihood of rewards for optimal decision-making. Using functional magnetic resonance imaging in humans, we found that healthy older adults had an abnormal signature of expected value, resulting in an incomplete reward prediction error (RPE) signal in the nucleus accumbens, a brain region that receives rich input projections from substantia nigra/ventral tegmental area (SN/VTA) dopaminergic neurons. Structural connectivity between SN/VTA and striatum, measured by diffusion tensor imaging, was tightly coupled to inter-individual differences in the expression of this expected reward value signal. The dopamine precursor levodopa (L-DOPA) increased the task-based learning rate and task performance in some older adults to the level of young adults. This drug effect was linked to restoration of a canonical neural RPE. Our results identify a neurochemical signature underlying abnormal reward processing in older adults and indicate that this can be modulated by L-DOPA.

  6. Art Painting Diagnostic Before Restoration with Terahertz and Millimeter Waves

    Science.gov (United States)

    Guillet, Jean-Paul; Roux, M.; Wang, K.; Ma, X.; Fauquet, F.; Balacey, H.; Recur, B.; Darracq, F.; Mounaix, P.

    2017-04-01

    Art painting diagnostic is commonly performed using electromagnetic waves at wavelengths from terahertz to X-ray. These former techniques are essential in conservation and art history research, but they could be also very useful for restoring artwork. While most studies use time domain imaging technique, in this study, a painting has been investigated using both time domain imaging (TDI) and frequency-modulated continuous wave (FMCW) system in the millimeter frequency range. By applying these systems to a painting of the eighteenth century, we detect and analyze the structure of some defects. This study underlines the differences between FMCW and TDI. We present the advantages and disadvantages of each technique on a real artwork.

  7. Art Painting Diagnostic Before Restoration with Terahertz and Millimeter Waves

    Science.gov (United States)

    Guillet, Jean-Paul; Roux, M.; Wang, K.; Ma, X.; Fauquet, F.; Balacey, H.; Recur, B.; Darracq, F.; Mounaix, P.

    2017-01-01

    Art painting diagnostic is commonly performed using electromagnetic waves at wavelengths from terahertz to X-ray. These former techniques are essential in conservation and art history research, but they could be also very useful for restoring artwork. While most studies use time domain imaging technique, in this study, a painting has been investigated using both time domain imaging (TDI) and frequency-modulated continuous wave (FMCW) system in the millimeter frequency range. By applying these systems to a painting of the eighteenth century, we detect and analyze the structure of some defects. This study underlines the differences between FMCW and TDI. We present the advantages and disadvantages of each technique on a real artwork.

  8. Terrorism, Forgiveness and Restorative Justice

    Directory of Open Access Journals (Sweden)

    Antony Pemberton

    2014-07-01

    Full Text Available This paper is intended to enhance understanding of the complexities of restorative justice in cases of terrorism from a victimological perspective. It does so first by analysing what separates terrorism from other forms of crime. The author argues that the main distinction concerns the peculiarly public nature of terrorism, in which the attack on the direct victims is intended to influence a (far larger group of so-called vicarious victims. This means that the public is likely to experience terrorist attacks as attacks on themselves. As a consequence the public can feel entitled to processes of forgiveness which in turn can conflict with the direct victims’ own experience. To illuminate this issue the paper proposes a novel distinction in third party forgiveness processes: between public forgiveness, i.e. forgiveness relating to the public wrongfulness inherent in crime, and vicarious forgiveness, i.e. the public’s experience of forgiveness itself. The complexities for restorative justice after terrorism can be then be viewed in terms of the tensions between the direct victims’ private and the publics’ vicarious forgiveness processes. Este artículo pretende facilitar la comprensión de las complejidades de la justicia restaurativa en casos de terrorismo desde una perspectiva victimológica. Lo hace primero mediante el análisis de lo que separa el terrorismo de otras formas de delincuencia. El autor sostiene que la distinción principal se refiere a la naturaleza pública específica del terrorismo, ya que mediante el ataque a las víctimas directas se pretende influir en el grupo (mucho más grande de las llamadas víctimas vicarias. Esto significa que es probable que el público sienta los ataques terroristas como ataques contra ellos mismos. De esta forma, el público puede sentirse con derecho sobre los procesos de perdón, lo que, a su vez, puede entrar en conflicto con la propia experiencia de las víctimas directas. Para iluminar

  9. Water Awareness Through Environmental Restoration

    Science.gov (United States)

    Davis-Caldwell, K.

    2012-04-01

    and negative effects of human presence on the local and global water supply. Student research scientifically tested ways to slow down the effects of run-off contaminants. Students also revisit water analysis and plant trees as buffers as part of their stream preservation efforts in a culminating activity. Oyster Reef Restoration Project: As a result of changes in climate, pollution and human consumption, the oyster population in the Chesapeake Bay had previously been on a rapid decline. The Oyster Reef Restoration Project allows students to understand the creatures of the bay and the cause of this decline. They explore the domino effect this has had on the quality of the water in the bay and future implications on the environment when the oyster population fluctuates significantly. Students construct concrete reefs and study the components of its contents and the reef's impact on the bay. Students are responsible for mixing, pouring and preparing the reef for its eventual drop in the bay. Wetlands Recovery: Following the elimination of a substantial amount of the natural wetlands behind the elementary and middle schools, a wetlands area was erected on the school grounds. This pond has been used to learn about habitats and the role humans, plants and organisms play in the preservation of the earth soil and water supply. This wetland is used by both the elementary and middle schools as a place for hands-on inquiry based learning. Students maintain the upkeep of the pond and teach other students at lower grades.

  10. The digital restoration of film

    Directory of Open Access Journals (Sweden)

    Catanese, Rossella

    2014-12-01

    Full Text Available Aquest article tracta sobre la conservació i la restauració de pel·lícules amb tecnologies digitals. Les pel·lícules, com a expressió de la memòria col·lectiva, formen part del patrimoni comú de la humanitat, i mereixen ser preservades i difoses. Per això, la qüestió de la preservació dels materials cinematogràfics està guanyant pes, sobretot si tenim en compte la fragilitat estructural i la curta durada de l'estoc de pel·lícules. L'estat actual del mitjà audiovisual és de transició: a poc a poc l'element analògic i fotoquímic és substituït pel sistema digital. I això influeix molt en les pràctiques de producció i distribució del cinema, i també en els debats teòrics sobre el mitjà: els criteris d'arxivament i els processos de restauració no són una excepció a aquesta lògica.Este artículo trata sobre la conservación y la restauración de películas con tecnologías digitales. Las películas, como expresión de la memoria colectiva, forman parte del patrimonio común de la humanidad, y merecen ser preservadas y difundidas. Por eso, la cuestión de la preservación de los materiales cinematográficos está ganando peso, sobre todo si tenemos en cuenta la fragilidad estructural y la corta duración del stock de películas. El estado actual del medio audiovisual es de transición: poco a poco el elemento analógico y fotoquímico es sustituido por el sistema digital. Lo cual influye mucho en las prácticas de producción y distribución del cine, y también en los debates teóricos sobre el medio: los criterios de archivo y los procesos de restauración no son una excepción a esta lógica.This article focuses on the issues of conservation and restoration of films through digital technologies. Films, as an expression of collective memory, become part of the common heritage of humankind, which deserves to be safeguarded and disseminated. As a consequence of this awareness, the issue of preserving cinematic

  11. Procedures for restoring vestibular disorders

    Directory of Open Access Journals (Sweden)

    Walther, Leif Erik

    2005-09-01

    Full Text Available This paper will discuss therapeutic possibilities for disorders of the vestibular organs and the neurons involved, which confront ENT clinicians in everyday practice. Treatment of such disorders can be tackled either symptomatically or causally. The possible strategies for restoring the body's vestibular sense, visual function and co-ordination include medication, as well as physical and surgical procedures. Prophylactic or preventive measures are possible in some disorders which involve vertigo (bilateral vestibulopathy, kinetosis, height vertigo, vestibular disorders when diving (Tables 1 and 2. Glucocorticoid and training therapy encourage the compensation of unilateral vestibular loss. In the case of a bilateral vestibular loss, it is important to treat the underlying disease (e.g. Cogan's disease. Although balance training does improve the patient's sense of balance, it will not restore it completely.In the case of Meniere's disease, there are a number of medications available to either treat bouts or to act as a prophylactic (e.g. dimenhydrinate or betahistine. In addition, there are non-ablative (sacculotomy as well as ablative surgical procedures (e.g. labyrinthectomy, neurectomy of the vestibular nerve. In everyday practice, it has become common to proceed with low risk therapies initially. The physical treatment of mild postural vertigo can be carried out quickly and easily in outpatients (repositioning or liberatory maneuvers. In very rare cases it may be necessary to carry out a semicircular canal occlusion. Isolated disturbances of the otolith function or an involvement of the otolith can be found in roughly 50% of labyrinth disturbances. A specific surgical procedure to selectively block the otolith organs is currently being studied. When an external perilymph fistula involving loss of perilymph is suspected, an exploratory tympanotomy involving also the round and oval window niches must be carried out. A traumatic rupture of the

  12. Monoenergetic computed tomography reconstructions reduce beam hardening artifacts from dental restorations.

    Science.gov (United States)

    Stolzmann, Paul; Winklhofer, Sebastian; Schwendener, Nicole; Alkadhi, Hatem; Thali, Michael J; Ruder, Thomas D

    2013-09-01

    The aim of this study was to assess the potential of monoenergetic computed tomography (CT) images to reduce beam hardening artifacts in comparison to standard CT images of dental restoration on dental post-mortem CT (PMCT). Thirty human decedents (15 male, 58 ± 22 years) with dental restorations were examined using standard single-energy CT (SECT) and dual-energy CT (DECT). DECT data were used to generate monoenergetic CT images, reflecting the X-ray attenuation at energy levels of 64, 69, 88 keV, and at an individually adjusted optimal energy level called OPTkeV. Artifact reduction and image quality of SECT and monoenergetic CT were assessed objectively and subjectively by two blinded readers. Subjectively, beam artifacts decreased visibly in 28/30 cases after monoenergetic CT reconstruction. Inter- and intra-reader agreement was good (k = 0.72, and k = 0.73 respectively). Beam hardening artifacts decreased significantly with increasing monoenergies (repeated-measures ANOVA p < 0.001). Artifact reduction was greatest on monoenergetic CT images at OPTkeV. Mean OPTkeV was 108 ± 17 keV. OPTkeV yielded the lowest difference between CT numbers of streak artifacts and reference tissues (-163 HU). Monoenergetic CT reconstructions significantly reduce beam hardening artifacts from dental restorations and improve image quality of post-mortem dental CT.

  13. Visual communication - Information and fidelity. [of images

    Science.gov (United States)

    Huck, Freidrich O.; Fales, Carl L.; Alter-Gartenberg, Rachel; Rahman, Zia-Ur; Reichenbach, Stephen E.

    1993-01-01

    This assessment of visual communication deals with image gathering, coding, and restoration as a whole rather than as separate and independent tasks. The approach focuses on two mathematical criteria, information and fidelity, and on their relationships to the entropy of the encoded data and to the visual quality of the restored image. Past applications of these criteria to the assessment of image coding and restoration have been limited to the link that connects the output of the image-gathering device to the input of the image-display device. By contrast, the approach presented in this paper explicitly includes the critical limiting factors that constrain image gathering and display. This extension leads to an end-to-end assessment theory of visual communication that combines optical design with digital processing.

  14. Inside the "Black Box" of River Restoration: Using Catchment History to Identify Disturbance and Response Mechanisms to Set Targets for Process-Based Restoration

    Directory of Open Access Journals (Sweden)

    Sarah Mika

    2010-12-01

    Full Text Available Many river restoration projects fail. Inadequate project planning underpins many of the reasons given for failure (such as setting overly ambitious goals; selecting inappropriate sites and techniques; losing stakeholder motivation; and neglecting to monitor, assess, and document projects. Another major problem is the lack of an agreed guiding image to direct the activities aimed at restoring the necessary biophysical and ecological processes within the logistic constraints of on-ground works. Despite a rich literature defining the components of restoration project planning, restoration ecology currently lacks an explicit and logical means of moving from the initial project vision through to on-ground strategies. Yet this process is fundamental because it directly links the ecological goals of the project to the on-ground strategies used to achieve them. We present a planning process that explicitly uses an interdisciplinary mechanistic model of disturbance drivers and system responses to build from the initial project vision to the implementation of on-ground works. A worked example on the Upper Hunter River in southeastern Australia shows how understanding catchment history can reveal disturbance and response mechanisms, thus facilitating process-based restoration.

  15. Geomorphic Analysis - Trinity River Restoration Potential

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The goal of the Trinity River project is to identify the potential positive effects of large-scale restoration actions in a 63 kilometer reach of the Trinity River...

  16. Habitat Analysis - Trinity River Restoration Potential

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The goal of the Trinity River project is to identify the potential positive effects of large-scale restoration actions in a 63 kilometer reach of the Trinity River...

  17. Western Lake Erie Restoration Assessment Degree Flowlines

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This represents the flowline network in Western Lale Erie Restoration Assessment (WLERA). It is attributed with the number of disconnections between the reach and...

  18. Saginaw Bay Restoration Assessment Degree Flowlines

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This represents the flowline network in Sagina Bay Restoration Assessment (SBRA). It is attributed with the number of disconnections between the reach and the...

  19. Connecting River Systems Restoration Assessment Degree Flowlines

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This represents the flowline network in Connecting River Systems Restoration Assessment (CRSRA). It is attributed with the number of disconnections between the reach...

  20. US Forest Service Integrated Resource Restoration (IRR)

    Data.gov (United States)

    US Forest Service, Department of Agriculture — A map service on the www depicting activities funded through the Integrated Resource Restoration (IRR) NFRR Budget Line Item and reported through the U.S. Forest...

  1. Stream restoration hydraulic design course: lecture notes

    National Research Council Canada - National Science Library

    Newbury, R

    2002-01-01

    Steam restoration encompasses a broad range of activities and disciplines. This lecture series is designed for practitioners who must fit habitat improvement works in the hydraulics of degraded channels...

  2. Conservation and Restoration - A Traceless Process?

    National Research Council Canada - National Science Library

    Marty, Christian

    2001-01-01

    Thanks to impulses from the humanities and the natural sciences, the profession of art conservation and restoration has emancipated itself over the past century from its origins as an artisan's craft...

  3. Commentary: Jail-based competency restoration.

    Science.gov (United States)

    Kapoor, Reena

    2011-01-01

    Many factors influence restoration of competence to stand trial: age, IQ, severity of mental illness, criminal history, treatment history, and others. This commentary poses the question of whether competency to stand trial is also influenced by the setting in which restoration treatment occurs. Jail-based competency-restoration programs, which are in their infancy and have yet to produce large-scale data demonstrating their efficacy, are examined. Several factors related to jail-based restoration are considered: choosing the right candidates for the program, impact of treatment in a punitive setting, ability to maintain separation between treaters and forensic evaluators, procedures for involuntary medication, aggregation of incompetent defendants in regional jails, effect on malingering, and cost savings.

  4. Fisheries Restoration Grant Program Projects [ds168

    Data.gov (United States)

    California Department of Resources — This shapefile (FRGP_All_020209.shp) represents the locations of all ongoing and completed salmonid restoration projects in California with existing records in the...

  5. Smooth coronal surface, resin restoration and microleakage.

    Science.gov (United States)

    Yanikoğlu, F; Türkmen, C; Kartal, N; Başaran, B

    1997-09-01

    The space between the resin and the cavity walls has always become interesting to search. The aim of this study was to evaluate any differences on leakage values of Class 5 type resin restorations prepared on surrounding surfaces of the tooth crown. Ninety human teeth were prepared as Class 5 cavities on buccal, lingual, mesial and distal surfaces and were randomly divided into groups for bevelling, groove preparation and as control. The subgroups were arranged as fluoride gel and/or sealant applications. Fluoride gel was applied following the cavity preparations. Sealant was applied over composite resin restorations. Treated teeth were thermocycled and immersed into dye solution for 96 hours. The restorations were evaluated in a stereo-microscope following the sectioning. Bevelling of the cavosurfaces and/or preparation of a groove addition to cavity procedures did not make any difference on the microleakage scores of the restorations done on either surfaces statistically.

  6. Ceramics as biomaterials for dental restoration.

    Science.gov (United States)

    Höland, Wolfram; Schweiger, Marcel; Watzke, Ronny; Peschke, Arnd; Kappert, Heinrich

    2008-11-01

    Sintered ceramics and glass-ceramics are widely used as biomaterials for dental restoration, especially as dental inlays, onlays, veneers, crowns or bridges. Biomaterials were developed either to veneer metal frameworks or to produce metal-free dental restorations. Different types of glass-ceramics and ceramics are available and necessary today to fulfill customers' needs (patients, dentists and dental technicians) regarding the properties of the biomaterials and the processing of the products. All of these different types of biomaterials already cover the entire range of indications of dental restorations. Today, patients are increasingly interested in metal-free restoration. Glass-ceramics are particularly suitable for fabricating inlays, crowns and small bridges, as these materials achieve very strong, esthetic results. High-strength ceramics are preferred in situations where the material is exposed to high masticatory forces.

  7. Connecting River Systems Restoration Assessment Composite Model

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Well-established conservation planning principles and techniques framed by geodesign were used to assess the restorability of areas that historically supported...

  8. Western Lake Erie Restoration Assessment Composite Model

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Well-established conservation planning principles and techniques framed by geodesign were used to assess the restorability of areas that historically supported...

  9. Saginaw Bay Restoration Assessment Composite Model

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Well-established conservation planning principles and techniques framed by geodesign were used to assess the restorability of areas that historically supported...

  10. The Management of Dissonance in Nature Restoration

    DEFF Research Database (Denmark)

    Clemmensen, Thomas Juel

    2016-01-01

    Nature restoration is far from a neural undertaking. Just like any other type of heritage production, it can be the source of dissonance—‘our’ nature is not necessary ‘their’ nature. Often this dissonance is managed in ways, which are not particularly sensitive to site-specificity. As exemplified...... by the Skjern River Restoration Project (1999-2003), one interpretation of the landscape sometimes suppresses other valid interpretations, neglecting its diverse history. Landscape architecture might, however, provide an alternative approach to nature restoration that is more site-specific, allowing...... for multiple interpretations to coexist. Indications can be found in the Re-naturalization of River Aire (2002-2015)—a restoration project, which reveals approaches that could be labelled landscape architecture specific....

  11. The Management of Dissonance in Nature Restoration

    DEFF Research Database (Denmark)

    Clemmensen, Thomas Juel

    2014-01-01

    Nature restoration is far from a neural undertaking. Just like any other type of heritage production, it can be the source of dissonance—‘our’ nature is not necessary ‘their’ nature. Often this dissonance is managed in ways, which are not particularly sensitive to site-specificity. As exemplified...... by the Skjern River Restoration Project (1999-2003), one interpretation of the landscape sometimes suppresses other valid interpretations, neglecting its diverse history. Landscape architecture might, however, provide an alternative approach to nature restoration that is more site-specific, allowing...... for multiple interpretations to coexist. Indications can be found in the Re-naturalization of River Aire (2002-2015)—a restoration project, which reveals approaches that could be labelled landscape architecture specific....

  12. Urban gardens: catalysts for restorative commons infrastructure

    Science.gov (United States)

    John Seitz

    2009-01-01

    One of 18 articles inspired by the Meristem 2007 Forum, "Restorative Commons for Community Health." The articles include interviews, case studies, thought pieces, and interdisciplinary theoretical works that explore the relationship between human health and the urban...

  13. Forest restoration, biodiversity and ecosystem functioning

    Directory of Open Access Journals (Sweden)

    Aerts Raf

    2011-11-01

    Full Text Available Abstract Globally, forests cover nearly one third of the land area and they contain over 80% of terrestrial biodiversity. Both the extent and quality of forest habitat continue to decrease and the associated loss of biodiversity jeopardizes forest ecosystem functioning and the ability of forests to provide ecosystem services. In the light of the increasing population pressure, it is of major importance not only to conserve, but also to restore forest ecosystems. Ecological restoration has recently started to adopt insights from the biodiversity-ecosystem functioning (BEF perspective. Central is the focus on restoring the relation between biodiversity and ecosystem functioning. Here we provide an overview of important considerations related to forest restoration that can be inferred from this BEF-perspective. Restoring multiple forest functions requires multiple species. It is highly unlikely that species-poor plantations, which may be optimal for above-ground biomass production, will outperform species diverse assemblages for a combination of functions, including overall carbon storage and control over water and nutrient flows. Restoring stable forest functions also requires multiple species. In particular in the light of global climatic change scenarios, which predict more frequent extreme disturbances and climatic events, it is important to incorporate insights from the relation between biodiversity and stability of ecosystem functioning into forest restoration projects. Rather than focussing on species per se, focussing on functional diversity of tree species assemblages seems appropriate when selecting tree species for restoration. Finally, also plant genetic diversity and above - below-ground linkages should be considered during the restoration process, as these likely have prominent but until now poorly understood effects at the level of the ecosystem. The BEF-approach provides a useful framework to evaluate forest restoration in an

  14. Alternatives to testosterone replacement: testosterone restoration.

    Science.gov (United States)

    McCullough, Andrew

    2015-01-01

    The European Male Aging Study has demonstrated that the hypogonadism of male aging is predominantly secondary. Theoretically with appropriate stimulation from the pituitary, the aging testis should be able to produce eugonadal levels of testosterone. The strategies for the treatment of late onset hypogonadism (LOH) have focused on replacement with exogenous testosterone versus restoration of endogenous production. The purpose of this article is to review existing peer-reviewed literature supporting the concept of restoration of endogenous testosterone in the treatment of LOH.

  15. Resin composites : Sandwich restorations and curing techniques

    OpenAIRE

    Lindberg, Anders

    2005-01-01

    Since the mid-1990s resin composite has been used for Class II restorations in stress-bearing areas as an alternative to amalgam. Reasons for this were the patients’ fear of mercury in dental amalgam and a growing demand for aesthetic restorations. During the last decades, the use of new resin composites with more optimized filler loading have resulted in reduced clinical wear. Improved and simplified amphiphilic bonding systems have been introduced. However, one of the main problems with res...

  16. Laser application in otology for hearing restoration

    Science.gov (United States)

    Lombardo, Igino

    1994-09-01

    Prior to the development of the stapes replacement prosthesis in the early 1950s, loss of hearing due to otosclerosis remained an untreatable disease. Today, loss of hearing due to otosclerosis can be restored in the majority of cases to near normal levels. Since 1980 the laser has played a major and important role in otosclerosis surgery. This paper explores the use of lasers for hearing restoration and compares the results of laser surgery to non-laser surgery.

  17. Restoration of the endodontically treated posterior tooth

    OpenAIRE

    Andrea Polesel

    2014-01-01

    Objectives: To analyse the key factors of the restoration in the posterior endodontically treated teeth, through a literature review and clinical cases presentation. To focus on the clinical advantages of the adhesive indirect restorations, describing the basic principles for long-term success. Materials and methods: The biomechanical changes due to the root canal therapy and the degree of healthy dental tissue lost because of pathology and iatrogenic factors are the critical points leadin...

  18. Marginal microfiltration in amalgam restorations. Review

    OpenAIRE

    Lahoud Salem, Víctor; Departamento Académico de Estomatología Rehabilitadora. Facultad de Odontología, Universidad Nacional Mayor de San Marcos, Lima. Perú.

    2014-01-01

    The present articule is review references from phenomenon of microfiltration in restorations with amalgam and yours consecuents in changes of color in the interface tooth-restorations, margin deterioted , sensitivity dentinarea postoperate, caries secondary and pulp inflamation. Besides naming the mechanicals for to reduce microfiltration, and yours effects for use of sealers dentinaries representation for the varnish cavitys and adhesive systens Conclusive indicate wath the amalgam is the ma...

  19. Hydromorphological restoration stimulates river ecosystem metabolism

    Science.gov (United States)

    Kupilas, Benjamin; Hering, Daniel; Lorenz, Armin W.; Knuth, Christoph; Gücker, Björn

    2017-04-01

    Both ecosystem structure and functioning determine ecosystem status and are important for the provision of goods and services to society. However, there is a paucity of research that couples functional measures with assessments of ecosystem structure. In mid-sized and large rivers, effects of restoration on key ecosystem processes, such as ecosystem metabolism, have rarely been addressed and remain poorly understood. We compared three reaches of the third-order, gravel-bed river Ruhr in Germany: two reaches restored with moderate (R1) and substantial effort (R2) and one upstream degraded reach (D). Hydromorphology, habitat composition, and hydrodynamics were assessed. We estimated gross primary production (GPP) and ecosystem respiration (ER) using the one-station open-channel diel dissolved oxygen change method over a 50-day period at the end of each reach. Moreover, we estimated metabolic rates of the combined restored reaches (R1 + R2) using the two-station open-channel method. Values for hydromorphological variables increased with restoration intensity (D macrophyte cover of total wetted area was highest in R2 and lowest in R1, with intermediate values in D. Station R2 had higher average GPP and ER than R1 and D. The combined restored reaches R1 + R2 also exhibited higher GPP and ER than the degraded upstream river (station D). Restoration increased river autotrophy, as indicated by elevated GPP : ER, and net ecosystem production (NEP) of restored reaches. Temporal patterns of ER closely mirrored those of GPP, pointing to the importance of autochthonous production for ecosystem functioning. In conclusion, high reach-scale restoration effort had considerable effects on river hydrodynamics and ecosystem functioning, which were mainly related to massive stands of macrophytes. High rates of metabolism and the occurrence of dense macrophyte stands may increase the assimilation of dissolved nutrients and the sedimentation of particulate nutrients, thereby positively

  20. [Dental restoration materials in pediatric dentistry].

    Science.gov (United States)

    Davidson, C L

    1997-02-01

    Restorative materials in pediatric dentistry have to fulfill special requirements. They should be easy to handle and applicable in a not always dry mouth. They should potentially be adhesive in order to avoid too much mechanical preparation. They do not have to be extremely wear resistant as the dwell time of the restorations is relatively short. Glass-ionomer cements and in particular the resin modified types possess properties which make them almost ideal for the required purpose.