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Sample records for blind source separation

  1. Convolutive Blind Source Separation Methods

    DEFF Research Database (Denmark)

    Pedersen, Michael Syskind; Larsen, Jan; Kjems, Ulrik;

    2008-01-01

    During the past decades, much attention has been given to the separation of mixed sources, in particular for the blind case where both the sources and the mixing process are unknown and only recordings of the mixtures are available. In several situations it is desirable to recover all sources fro...

  2. Blind source separation dependent component analysis

    CERN Document Server

    Xiang, Yong; Yang, Zuyuan

    2015-01-01

    This book provides readers a complete and self-contained set of knowledge about dependent source separation, including the latest development in this field. The book gives an overview on blind source separation where three promising blind separation techniques that can tackle mutually correlated sources are presented. The book further focuses on the non-negativity based methods, the time-frequency analysis based methods, and the pre-coding based methods, respectively.

  3. Transform domain steganography with blind source separation

    Science.gov (United States)

    Jouny, Ismail

    2015-05-01

    This paper applies blind source separation or independent component analysis for images that may contain mixtures of text, audio, or other images for steganography purposes. The paper focuses on separating mixtures in the transform domain such as Fourier domain or the Wavelet domain. The study addresses the effectiveness of steganography when using linear mixtures of multimedia components and the ability of standard blind sources separation techniques to discern hidden multimedia messages. Mixing in the space, frequency, and wavelet (scale) domains is compared. Effectiveness is measured using mean square error rate between original and recovered images.

  4. Blind source separation theory and applications

    CERN Document Server

    Yu, Xianchuan; Xu, Jindong

    2013-01-01

    A systematic exploration of both classic and contemporary algorithms in blind source separation with practical case studies    The book presents an overview of Blind Source Separation, a relatively new signal processing method.  Due to the multidisciplinary nature of the subject, the book has been written so as to appeal to an audience from very different backgrounds. Basic mathematical skills (e.g. on matrix algebra and foundations of probability theory) are essential in order to understand the algorithms, although the book is written in an introductory, accessible style. This book offers

  5. Blind Source Separation: the Sparsity Revolution

    OpenAIRE

    Bobin, J.; Starck, Jean-Luc; Moudden, Y.; Fadili, Jalal M.

    2008-01-01

    Over the last few years, the development of multi-channel sensors motivated interest in methods for the coherent processing of multivariate data. Some specific issues have already been addressed as testified by the wide literature on the so-called blind source separation (BSS) problem. In this context, as clearly emphasized by previous work, it is fundamental that the sources to be retrieved present some quantitatively measurable diversity. Recently, sparsity and morphological diversity have ...

  6. Grading learning for blind source separation

    Institute of Scientific and Technical Information of China (English)

    张贤达; 朱孝龙; 保铮

    2003-01-01

    By generalizing the learning rate parameter to a learning rate matrix, this paper proposes agrading learning algorithm for blind source separation. The whole learning process is divided into threestages: initial stage, capturing stage and tracking stage. In different stages, different learning rates areused for each output component, which is determined by its dependency on other output components. Itis shown that the grading learning algorithm is equivariant and can keep the separating matrix from be-coming singular. Simulations show that the proposed algorithm can achieve faster convergence, bettersteady-state performance and higher numerical robustness, as compared with the existing algorithmsusing fixed, time-descending and adaptive learning rates.

  7. Multistage decomposition algorithm for blind source separation

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A new algorithm for blind source separation is proposed, which only extracts the single independent component at each stage. The single independent component is acquired by an iterative algorithm for searching for the optimal solution of the defined cost function. Moreover, all the independent components are obtained by systematic multistage decomposition and multistage reconstruction. When there is spatially colored noise, the performance of this algorithm is advantageous over jointly approximated diagonalization of eigen-matrices (JADE). Simulated results show that if the number of source signals is more than 25, its computational complexity is lower than that of JADE.

  8. Blind Source Separation For Ion Mobility Spectra

    International Nuclear Information System (INIS)

    Miniaturization is a powerful trend for smart chemical instrumentation in a diversity of applications. It is know that miniaturization in IMS leads to a degradation of the system characteristics. For the present work, we are interested in signal processing solutions to mitigate limitations introduced by limited drift tube length that basically involve a loss of chemical selectivity. While blind source separation techniques (BSS) are popular in other domains, their application for smart chemical instrumentation is limited. However, in some conditions, basically linearity, BSS may fully recover the concentration time evolution and the pure spectra with few underlying hypothesis. This is extremely helpful in conditions where non-expected chemical interferents may appear, or unwanted perturbations may pollute the spectra. SIMPLISMA has been advocated by Harrington et al. in several papers. However, more modern methods of BSS for bilinear decomposition with the restriction of positiveness have appeared in the last decade. In order to explore and compare the performances of those methods a series of experiments were performed.

  9. Bayesian Blind Source Separation of Positive Non Stationary Sources

    Science.gov (United States)

    Ichir, Mahieddine M.; Mohammad-Djafari, Ali

    2004-11-01

    In this contribution, we address the problem of blind non negative source separation. This problem finds its application in many fields of data analysis. We propose herein a novel approach based on Gamma mixture probability priors: Gamma densities to constraint the unobserved sources to lie on the positive half plane; a mixture density with a first order Markov model on the associated hidden variables to account for eventual non stationarity on the sources. Posterior mean estimates are obtained via appropriate Monte Carlo Markov Chain sampling.

  10. Novel blind source separation algorithm using Gaussian mixture density function

    Institute of Scientific and Technical Information of China (English)

    孔薇; 杨杰; 周越

    2004-01-01

    The blind source separation (BSS) is an important task for numerous applications in signal processing, communications and array processing. But for many complex sources blind separation algorithms are not efficient because the probability distribution of the sources cannot be estimated accurately. So in this paper, to justify the ME(maximum enteropy) approach, the relation between the ME and the MMI(minimum mutual information) is elucidated first. Then a novel algorithm that uses Gaussian mixture density to approximate the probability distribution of the sources is presented based on the ME approach. The experiment of the BSS of ship-radiated noise demonstrates that the proposed algorithm is valid and efficient.

  11. Gradient Flow Convolutive Blind Source Separation

    DEFF Research Database (Denmark)

    Pedersen, Michael Syskind; Nielsen, Chinton Møller

    2004-01-01

    Experiments have shown that the performance of instantaneous gradient flow beamforming by Cauwenberghs et al. is reduced significantly in reverberant conditions. By expanding the gradient flow principle to convolutive mixtures, separation in a reverberant environment is possible. By use of a circ......Experiments have shown that the performance of instantaneous gradient flow beamforming by Cauwenberghs et al. is reduced significantly in reverberant conditions. By expanding the gradient flow principle to convolutive mixtures, separation in a reverberant environment is possible. By use...

  12. Single channel blind source separation based on ICA feature extraction

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A new technique is proposed to solve the blind source separation (BSS) given only a single channel observation. The basis functions and the density of the coefficients of source signals learned by ICA are used as the prior knowledge. Based on the learned prior information the learning rules of single channel BSS are presented by maximizing the joint log likelihood of the mixed sources to obtain source signals from single observation,in which the posterior density of the given measurements is maximized. The experimental results exhibit a successful separation performance for mixtures of speech and music signals.

  13. Sparsity and Morphological Diversity in Blind Source Separation

    OpenAIRE

    Bobin, Jérome; Starck, Jean-Luc; Fadili, Jalal M.; Moudden, Yassir

    2007-01-01

    Over the last few years, the development of multichannel sensors motivated interest in methods for the coherent processing of multivariate data. Some specific issues have already been addressed as testified by the wide literature on the so-caIled blind source separation (BSS) problem. In this context, as clearly emphasized by previous work, it is fundamental that the sources to be retrieved present some quantitatively measurable diversity. Recently, sparsity and morphological diversity have e...

  14. Blind source separation based on generalized gaussian model

    Institute of Scientific and Technical Information of China (English)

    YANG Bin; KONG Wei; ZHOU Yue

    2007-01-01

    Since in most blind source separation (BSS) algorithms the estimations of probability density function (pdf) of sources are fixed or can only switch between one sup-Gaussian and other sub-Gaussian model,they may not be efficient to separate sources with different distributions. So to solve the problem of pdf mismatch and the separation of hybrid mixture in BSS, the generalized Gaussian model (GGM) is introduced to model the pdf of the sources since it can provide a general structure of univariate distributions. Its great advantage is that only one parameter needs to be determined in modeling the pdf of different sources, so it is less complex than Gaussian mixture model. By using maximum likelihood (ML) approach, the convergence of the proposed algorithm is improved. The computer simulations show that it is more efficient and valid than conventional methods with fixed pdf estimation.

  15. Blind source separation advances in theory, algorithms and applications

    CERN Document Server

    Wang, Wenwu

    2014-01-01

    Blind Source Separation intends to report the new results of the efforts on the study of Blind Source Separation (BSS). The book collects novel research ideas and some training in BSS, independent component analysis (ICA), artificial intelligence and signal processing applications. Furthermore, the research results previously scattered in many journals and conferences worldwide are methodically edited and presented in a unified form. The book is likely to be of interest to university researchers, R&D engineers and graduate students in computer science and electronics who wish to learn the core principles, methods, algorithms, and applications of BSS. Dr. Ganesh R. Naik works at University of Technology, Sydney, Australia; Dr. Wenwu Wang works at University of Surrey, UK.

  16. FREQUENCY OVERLAPPED SIGNAL IDENTIFICATION USING BLIND SOURCE SEPARATION

    Institute of Scientific and Technical Information of China (English)

    WANG Junfeng; SHI Tielin; HE Lingsong; YANG Shuzi

    2006-01-01

    The concepts, principles and usages of principal component analysis (PCA) and independent component analysis (ICA) are interpreted. Then the algorithm and methodology of ICA-based blind source separation (BSS), in which the pre-whitened based on PCA for observed signals is used, are researched. Aiming at the mixture signals, whose frequency components are overlapped by each other, a simulation of BSS to separate this type of mixture signals by using theory and approach of BSS has been done. The result shows that the BSS has some advantages what the traditional methodology of frequency analysis has not.

  17. Underdetermined Blind Audio Source Separation Using Modal Decomposition

    Directory of Open Access Journals (Sweden)

    Aïssa-El-Bey Abdeldjalil

    2007-01-01

    Full Text Available This paper introduces new algorithms for the blind separation of audio sources using modal decomposition. Indeed, audio signals and, in particular, musical signals can be well approximated by a sum of damped sinusoidal (modal components. Based on this representation, we propose a two-step approach consisting of a signal analysis (extraction of the modal components followed by a signal synthesis (grouping of the components belonging to the same source using vector clustering. For the signal analysis, two existing algorithms are considered and compared: namely the EMD (empirical mode decomposition algorithm and a parametric estimation algorithm using ESPRIT technique. A major advantage of the proposed method resides in its validity for both instantaneous and convolutive mixtures and its ability to separate more sources than sensors. Simulation results are given to compare and assess the performance of the proposed algorithms.

  18. Underdetermined Blind Audio Source Separation Using Modal Decomposition

    Directory of Open Access Journals (Sweden)

    Abdeldjalil Aïssa-El-Bey

    2007-03-01

    Full Text Available This paper introduces new algorithms for the blind separation of audio sources using modal decomposition. Indeed, audio signals and, in particular, musical signals can be well approximated by a sum of damped sinusoidal (modal components. Based on this representation, we propose a two-step approach consisting of a signal analysis (extraction of the modal components followed by a signal synthesis (grouping of the components belonging to the same source using vector clustering. For the signal analysis, two existing algorithms are considered and compared: namely the EMD (empirical mode decomposition algorithm and a parametric estimation algorithm using ESPRIT technique. A major advantage of the proposed method resides in its validity for both instantaneous and convolutive mixtures and its ability to separate more sources than sensors. Simulation results are given to compare and assess the performance of the proposed algorithms.

  19. An autonomous surveillance system for blind sources localization and separation

    Science.gov (United States)

    Wu, Sean; Kulkarni, Raghavendra; Duraiswamy, Srikanth

    2013-05-01

    This paper aims at developing a new technology that will enable one to conduct an autonomous and silent surveillance to monitor sound sources stationary or moving in 3D space and a blind separation of target acoustic signals. The underlying principle of this technology is a hybrid approach that uses: 1) passive sonic detection and ranging method that consists of iterative triangulation and redundant checking to locate the Cartesian coordinates of arbitrary sound sources in 3D space, 2) advanced signal processing to sanitizing the measured data and enhance signal to noise ratio, and 3) short-time source localization and separation to extract the target acoustic signals from the directly measured mixed ones. A prototype based on this technology has been developed and its hardware includes six B and K 1/4-in condenser microphones, Type 4935, two 4-channel data acquisition units, Type NI-9234, with a maximum sampling rate of 51.2kS/s per channel, one NI-cDAQ 9174 chassis, a thermometer to measure the air temperature, a camera to view the relative positions of located sources, and a laptop to control data acquisition and post processing. Test results for locating arbitrary sound sources emitting continuous, random, impulsive, and transient signals, and blind separation of signals in various non-ideal environments is presented. This system is invisible to any anti-surveillance device since it uses the acoustic signal emitted by a target source. It can be mounted on a robot or an unmanned vehicle to perform various covert operations, including intelligence gathering in an open or a confined field, or to carry out the rescue mission to search people trapped inside ruins or buried under wreckages.

  20. Blind Source Separation with Compressively Sensed Linear Mixtures

    CERN Document Server

    Kleinsteuber, Martin

    2011-01-01

    This work studies the problem of simultaneously separating and reconstructing signals from compressively sensed linear mixtures. We assume that all source signals share a common sparse representation basis. The approach combines classical Compressive Sensing (CS) theory with a linear mixing model. It allows the mixtures to be sampled independently of each other. If samples are acquired in the time domain, this means that the sensors need not be synchronized. Since Blind Source Separation (BSS) from a linear mixture is only possible up to permutation and scaling, factoring out these ambiguities leads to a minimization problem on the so-called oblique manifold. We develop a geometric conjugate subgradient method that scales to large systems for solving the problem. Numerical results demonstrate the promising performance of the proposed algorithm compared to several state of the art methods.

  1. Exploiting Narrowband Efficiency for Broadband Convolutive Blind Source Separation

    Directory of Open Access Journals (Sweden)

    Aichner Robert

    2007-01-01

    Full Text Available Based on a recently presented generic broadband blind source separation (BSS algorithm for convolutive mixtures, we propose in this paper a novel algorithm combining advantages of broadband algorithms with the computational efficiency of narrowband techniques. By selective application of the Szegö theorem which relates properties of Toeplitz and circulant matrices, a new normalization is derived as a special case of the generic broadband algorithm. This results in a computationally efficient and fast converging algorithm without introducing typical narrowband problems such as the internal permutation problem or circularity effects. Moreover, a novel regularization method for the generic broadband algorithm is proposed and subsequently also derived for the proposed algorithm. Experimental results in realistic acoustic environments show improved performance of the novel algorithm compared to previous approximations.

  2. Blind source separation problem in GPS time series

    Science.gov (United States)

    Gualandi, A.; Serpelloni, E.; Belardinelli, M. E.

    2016-04-01

    A critical point in the analysis of ground displacement time series, as those recorded by space geodetic techniques, is the development of data-driven methods that allow the different sources of deformation to be discerned and characterized in the space and time domains. Multivariate statistic includes several approaches that can be considered as a part of data-driven methods. A widely used technique is the principal component analysis (PCA), which allows us to reduce the dimensionality of the data space while maintaining most of the variance of the dataset explained. However, PCA does not perform well in finding the solution to the so-called blind source separation (BSS) problem, i.e., in recovering and separating the original sources that generate the observed data. This is mainly due to the fact that PCA minimizes the misfit calculated using an L2 norm (χ 2), looking for a new Euclidean space where the projected data are uncorrelated. The independent component analysis (ICA) is a popular technique adopted to approach the BSS problem. However, the independence condition is not easy to impose, and it is often necessary to introduce some approximations. To work around this problem, we test the use of a modified variational Bayesian ICA (vbICA) method to recover the multiple sources of ground deformation even in the presence of missing data. The vbICA method models the probability density function (pdf) of each source signal using a mix of Gaussian distributions, allowing for more flexibility in the description of the pdf of the sources with respect to standard ICA, and giving a more reliable estimate of them. Here we present its application to synthetic global positioning system (GPS) position time series, generated by simulating deformation near an active fault, including inter-seismic, co-seismic, and post-seismic signals, plus seasonal signals and noise, and an additional time-dependent volcanic source. We evaluate the ability of the PCA and ICA decomposition

  3. Convergent Bayesian formulations of blind source separation and electromagnetic source estimation

    OpenAIRE

    Knuth, Kevin H.; Vaughan Jr, Herbert G.

    2015-01-01

    We consider two areas of research that have been developing in parallel over the last decade: blind source separation (BSS) and electromagnetic source estimation (ESE). BSS deals with the recovery of source signals when only mixtures of signals can be obtained from an array of detectors and the only prior knowledge consists of some information about the nature of the source signals. On the other hand, ESE utilizes knowledge of the electromagnetic forward problem to assign source signals to th...

  4. Decentralized modal identification using sparse blind source separation

    International Nuclear Information System (INIS)

    Popular ambient vibration-based system identification methods process information collected from a dense array of sensors centrally to yield the modal properties. In such methods, the need for a centralized processing unit capable of satisfying large memory and processing demands is unavoidable. With the advent of wireless smart sensor networks, it is now possible to process information locally at the sensor level, instead. The information at the individual sensor level can then be concatenated to obtain the global structure characteristics. A novel decentralized algorithm based on wavelet transforms to infer global structure mode information using measurements obtained using a small group of sensors at a time is proposed in this paper. The focus of the paper is on algorithmic development, while the actual hardware and software implementation is not pursued here. The problem of identification is cast within the framework of under-determined blind source separation invoking transformations of measurements to the time–frequency domain resulting in a sparse representation. The partial mode shape coefficients so identified are then combined to yield complete modal information. The transformations are undertaken using stationary wavelet packet transform (SWPT), yielding a sparse representation in the wavelet domain. Principal component analysis (PCA) is then performed on the resulting wavelet coefficients, yielding the partial mixing matrix coefficients from a few measurement channels at a time. This process is repeated using measurements obtained from multiple sensor groups, and the results so obtained from each group are concatenated to obtain the global modal characteristics of the structure

  5. A DIGITAL COLOR IMAGE WATERMARKING SYSTEM USING BLIND SOURCE SEPARATION

    Directory of Open Access Journals (Sweden)

    Sangeeta D. Jadhav

    2013-12-01

    Full Text Available An attempt is made to implement a digital color image-adaptive watermarking scheme in spatial domain and hybrid domain i.e host image in wavelet domain and watermark in spatial domain. Blind Source Separation (BSS is used to extract the watermark The novelty of the presented scheme lies in determining the mixing matrix for BSS model using BFGS (Broyden– Fletcher–Goldfarb–Shanno optimization technique. This method is based on the smooth and textured portions of the image. Texture analysis is carried based on energy content of the image (using GLCM which makes the method image adaptive to embed color watermark. The performance evaluation is carried for hybrid domain of various color spaces like YIQ, HSI and YCbCr and the feasibility of optimization algorithm for finding mixing matrix is also checked for these color spaces. Three ICA (Independent Component Analysis/BSS algorithms are used in extraction procedure ,through which the watermark can be retrieved efficiently . An effort is taken to find out the best suited color space to embed the watermark which satisfies the condition of imperceptibility and robustness against various attacks.

  6. Combining Superdirective Beamforming and Frequency-Domain Blind Source Separation for Highly Reverberant Signals

    Directory of Open Access Journals (Sweden)

    Lin Wang

    2010-01-01

    Full Text Available Frequency-domain blind source separation (BSS performs poorly in high reverberation because the independence assumption collapses at each frequency bins when the number of bins increases. To improve the separation result, this paper proposes a method which combines two techniques by using beamforming as a preprocessor of blind source separation. With the sound source locations supposed to be known, the mixed signals are dereverberated and enhanced by beamforming; then the beamformed signals are further separated by blind source separation. To implement the proposed method, a superdirective fixed beamformer is designed for beamforming, and an interfrequency dependence-based permutation alignment scheme is presented for frequency-domain blind source separation. With beamforming shortening mixing filters and reducing noise before blind source separation, the combined method works better in reverberation. The performance of the proposed method is investigated by separating up to 4 sources in different environments with reverberation time from 100 ms to 700 ms. Simulation results verify the outperformance of the proposed method over using beamforming or blind source separation alone. Analysis demonstrates that the proposed method is computationally efficient and appropriate for real-time processing.

  7. Convergent Bayesian formulations of blind source separation and electromagnetic source estimation

    CERN Document Server

    Knuth, Kevin H

    2015-01-01

    We consider two areas of research that have been developing in parallel over the last decade: blind source separation (BSS) and electromagnetic source estimation (ESE). BSS deals with the recovery of source signals when only mixtures of signals can be obtained from an array of detectors and the only prior knowledge consists of some information about the nature of the source signals. On the other hand, ESE utilizes knowledge of the electromagnetic forward problem to assign source signals to their respective generators, while information about the signals themselves is typically ignored. We demonstrate that these two techniques can be derived from the same starting point using the Bayesian formalism. This suggests a means by which new algorithms can be developed that utilize as much relevant information as possible. We also briefly mention some preliminary work that supports the value of integrating information used by these two techniques and review the kinds of information that may be useful in addressing the...

  8. Blind source separation of internal combustion engine piston slap from other measured vibration signals

    Science.gov (United States)

    Liu, Xianhua; Randall, R. B.

    2005-11-01

    Internal combustion engines have several vibration sources, such as combustion, fuel injection, piston slap and valve operation. For machine condition monitoring or design improvement purposes, it is necessary to separate the vibration signals caused by different sources and then analyse each of them individually. However, traditional frequency analysis techniques are not very useful due to overlap of the different sources over a wide frequency range. This paper attempts to separate the vibration sources, especially piston slap, by using blind source separation techniques with the intention of revealing the potential of the new technique for solving mechanical vibration problems. The BSS method and the Blind least mean square algorithm using Gray's variable norm as a measure of non-Gaussianity of the sources is briefly described and separation results for both simulated and measured data are presented and discussed.

  9. Blind Source Separation Based on Covariance Ratio and Artificial Bee Colony Algorithm

    Directory of Open Access Journals (Sweden)

    Lei Chen

    2014-01-01

    Full Text Available The computation amount in blind source separation based on bioinspired intelligence optimization is high. In order to solve this problem, we propose an effective blind source separation algorithm based on the artificial bee colony algorithm. In the proposed algorithm, the covariance ratio of the signals is utilized as the objective function and the artificial bee colony algorithm is used to solve it. The source signal component which is separated out, is then wiped off from mixtures using the deflation method. All the source signals can be recovered successfully by repeating the separation process. Simulation experiments demonstrate that significant improvement of the computation amount and the quality of signal separation is achieved by the proposed algorithm when compared to previous algorithms.

  10. Blind Source Separation with Conjugate Gradient Algorithm and Kurtosis Maximization Criterion

    Directory of Open Access Journals (Sweden)

    Sanjeev N Jain

    2016-02-01

    Full Text Available Blind source separation (BSS is a technique for estimating individual source components from their mixtures at multiple sensors. It is called blind because any additional other information will not be used besides the mixtures. Recently, blind source separation has received attention because of its potential applications in signal processing such as in speech recognition systems, telecommunications and medical signal processing. Blind source separation of super and sub-Gaussian Signal is proposed utilizing conjugate gradient algorithm and kurtosis maximization criteria. In our previous paper, ABC algorithm was utilized to blind source separation and here, we improve the technique with changes in fitness function and scout bee phase. Fitness function is improved with the use of kurtosis maximization criterion and scout bee phase is improved with use of conjugate gradient algorithm. The evaluation metrics used for performance evaluation are fitness function values and distance values. Comparative analysis is also carried out by comparing our proposed technique to other prominent techniques. The technique achieved average distance of 38.39, average fitness value of 6.94, average Gaussian distance of 58.60 and average Gaussian fitness as 5.02. The technique attained lowest average distance value among all techniques and good values for all other evaluation metrics which shows the effectiveness of the proposed technique.

  11. Blind source separation with unknown and dynamically changing number of source signals

    Institute of Scientific and Technical Information of China (English)

    YE Jimin; ZHANG Xianda; ZHU Xiaolong

    2006-01-01

    The contrast function remains to be an open problem in blind source separation (BSS) when the number of source signals is unknown and/or dynamically changed.The paper studies this problem and proves that the mutual information is still the contrast function for BSS if the mixing matrix is of full column rank. The mutual information reaches its minimum at the separation points, where the random outputs of the BSS system are the scaled and permuted source signals, while the others are zero outputs. Using the property that the transpose of the mixing matrix and a matrix composed by m observed signals have the indentical null space with probability one, a practical method, which can detect the unknown number of source signals n, ulteriorly traces the dynamical change of the sources number with a few of data, is proposed. The effectiveness of the proposed theorey and the developed novel algorithm is verified by adaptive BSS simulations with unknown and dynamically changing number of source signals.

  12. A Nonlinear Blind Source Separation Method Based On Radial Basis Function and Quantum Genetic Algorithm

    Directory of Open Access Journals (Sweden)

    Wang Pidong

    2016-01-01

    Full Text Available Blind source separation is a hot topic in signal processing. Most existing works focus on dealing with linear combined signals, while in practice we always encounter with nonlinear mixed signals. To address the problem of nonlinear source separation, in this paper we propose a novel algorithm using radial basis function neutral network, optimized by multi-universe parallel quantum genetic algorithm. Experiments show the efficiency of the proposed method.

  13. Semi-blind Source Separation Using Head-Related Transfer Functions

    DEFF Research Database (Denmark)

    Pedersen, Michael Syskind; Hansen, Lars Kai; Kjems, Ulrik;

    2004-01-01

    An online blind source separation algorithm which is a special case of the geometric algorithm by Parra and Fancourt has been implemented for the purpose of separating sounds recorded at microphones placed at each side of the head. By using the assumption that the position of the two sounds...... are known, the source separation algorithm has been geometrically constrained. Since the separation takes place in a non free-field, a head-related transfer function (HRTF) is used to simulate the response between microphones placed at the two ears. The use of a HRTF instead of assuming free-field improves...

  14. RESEARCH OF QUANTUM GENETIC ALGORITH AND ITS APPLICATION IN BLIND SOURCE SEPARATION

    Institute of Scientific and Technical Information of China (English)

    Yang Junan; Li Bin; Zhuang Zhenquan

    2003-01-01

    This letter proposes two algorithms: a novel Quantum Genetic Algorithm (QGA)based on the improvement of Han's Genetic Quantum Algorithm (GQA) and a new Blind Source Separation (BSS) method based on QGA and Independent Component Analysis (ICA). The simulation result shows that the efficiency of the new BSS method is obviously higher than that of the Conventional Genetic Algorithm (CGA).

  15. Blind source separation of fMRI data by means of factor analytic transformations

    NARCIS (Netherlands)

    Langers, Dave R. M.

    2009-01-01

    In this study, the application of factor analytic (FA) rotation methods in the context of neuroimaging data analysis was explored. Three FA algorithms (ProMax, QuartiMax, and VariMax) were employed to carry out blind source separation in a functional magnetic resonance imaging (fMRI) experiment that

  16. ICAR, a tool for Blind Source Separation using Fourth Order Statistics only

    OpenAIRE

    Albera, Laurent; Férreol, Anne; Chevalier, Pascal; Comon, Pierre

    2005-01-01

    The problem of blind separation of overdetermined mixtures of sources, that is, with fewer sources than (or as many sources as) sensors, is addressed in this paper. A new method, named ICAR (Independent Component Analysis using Redundancies in the quadricovariance), is proposed in order to process complex data. This method, without any whitening operation, only exploits some redundancies of a particular quadricovariance matrix of the data. Computer simulations demonstrate that ICAR offers in ...

  17. Blind separation of sound sources from the principle of least spatial entropy

    Science.gov (United States)

    Dong, Bin; Antoni, Jérôme; Zhang, Erliang

    2014-04-01

    The aim of the paper is to offer a method for separating incoherent and compact sound sources which may overlap in both the space and frequency domains. This is found of interest in acoustical applications involving the identification and ranking of sound sources stemming from different physical origins. The principle proceeds in two steps, the first one being reminiscent to source reconstruction (e.g. as in near-field acoustical holography) and the second one to blind source separation. Specifically, the source mixture is first expanded into a linear combination of spatial basis functions whose coefficients are set by backpropagating the pressures measured by an array of microphones to the source domain. This leads to a formulation similar, but no identical, to blind source separation. In the second step, these coefficients are blindly separated into uncorrelated latent variables, assigned to incoherent "virtual sources". These are shown to be defined up to an arbitrary rotation. A unique set of sound sources is finally recovered by searching for that rotation (by conjugate gradient descent in the Stiefel manifold of unitary matrices) which maximizes their spatial compactness, as measured either by their spatial variance or their spatial entropy. This results in the proposal of two separation criteria coined "least spatial variance" and "least spatial entropy", respectively. The same concept of spatial entropy, which is central to the paper, is also exploited in defining a new criterion, the entropic L-curve, dedicated to determining the number of active sound sources. The idea consists in considering the number of sources that achieves the best compromise between a low spatial entropy (as expected from compact sources) and a low statistical entropy (as expected from a low residual error). The proposed methodology is validated on both laboratory experiments and numerical data, and illustrated on an industrial example concerned with the ranking of sound sources on

  18. Blind source separation of ship-radiated noise based on generalized Gaussian model

    Institute of Scientific and Technical Information of China (English)

    Kong Wei; Yang Bin

    2006-01-01

    When the distribution of the sources cannot be estimated accurately, the ICA algorithms failed to separate the mixtures blindly. The generalized Gaussian model (GGM) is presented in ICA algorithm since it can model nonGaussian statistical structure of different source signals easily. By inferring only one parameter, a wide class of statistical distributions can be characterized. By using maximum likelihood (ML) approach and natural gradient descent, the learning rules of blind source separation (BSS) based on GGM are presented. The experiment of the ship-radiated noise demonstrates that the GGM can model the distributions of the ship-radiated noise and sea noise efficiently, and the learning rules based on GGM gives more successful separation results after comparing it with several conventional methods such as high order cumulants and Gaussian mixture density function.

  19. Overcomplete Blind Source Separation by Combining ICA and Binary Time-Frequency Masking

    DEFF Research Database (Denmark)

    Pedersen, Michael Syskind; Wang, DeLiang; Larsen, Jan;

    2005-01-01

    A limitation in many source separation tasks is that the number of source signals has to be known in advance. Further, in order to achieve good performance, the number of sources cannot exceed the number of sensors. In many real-world applications these limitations are too strict. We propose a...... novel method for over-complete blind source separation. Two powerful source separation techniques have been combined, independent component analysis and binary time-frequency masking. Hereby, it is possible to iteratively extract each speech signal from the mixture. By using merely two microphones we...... can separate up to six mixed speech signals under anechoic conditions. The number of source signals is not assumed to be known in advance. It is also possible to maintain the extracted signals as stereo signals...

  20. Blind separation of sources in nonlinear convolved mixture based on a novel network

    Institute of Scientific and Technical Information of China (English)

    胡英; 杨杰; 沈利

    2004-01-01

    Blind separation of independent sources from their nonlinear convoluted mixtures is a more realistic problem than from linear ones. A solution to this problem based on the Entropy Maximization principle is presented. First we propose a novel two-layer network as the de-mixing system to separate sources in nonlinear convolved mixture. In output layer of our network we use feedback network architecture to cope with convoluted mixtures. Then we derive learning algorithms for the two-layer network by maximizing the information entropy. Based on the comparison of the computer simulation results, it can be concluded that the proposed algorithm has a better nonlinear convolved blind signal separation effect than the H.H. Y' s algorithm.

  1. Cultured Cortical Neurons Can Perform Blind Source Separation According to the Free-Energy Principle.

    Directory of Open Access Journals (Sweden)

    Takuya Isomura

    2015-12-01

    Full Text Available Blind source separation is the computation underlying the cocktail party effect--a partygoer can distinguish a particular talker's voice from the ambient noise. Early studies indicated that the brain might use blind source separation as a signal processing strategy for sensory perception and numerous mathematical models have been proposed; however, it remains unclear how the neural networks extract particular sources from a complex mixture of inputs. We discovered that neurons in cultures of dissociated rat cortical cells could learn to represent particular sources while filtering out other signals. Specifically, the distinct classes of neurons in the culture learned to respond to the distinct sources after repeating training stimulation. Moreover, the neural network structures changed to reduce free energy, as predicted by the free-energy principle, a candidate unified theory of learning and memory, and by Jaynes' principle of maximum entropy. This implicit learning can only be explained by some form of Hebbian plasticity. These results are the first in vitro (as opposed to in silico demonstration of neural networks performing blind source separation, and the first formal demonstration of neuronal self-organization under the free energy principle.

  2. Blind Separation of Nonstationary Sources Based on Spatial Time-Frequency Distributions

    Directory of Open Access Journals (Sweden)

    Zhang Yimin

    2006-01-01

    Full Text Available Blind source separation (BSS based on spatial time-frequency distributions (STFDs provides improved performance over blind source separation methods based on second-order statistics, when dealing with signals that are localized in the time-frequency (t-f domain. In this paper, we propose the use of STFD matrices for both whitening and recovery of the mixing matrix, which are two stages commonly required in many BSS methods, to provide robust BSS performance to noise. In addition, a simple method is proposed to select the auto- and cross-term regions of time-frequency distribution (TFD. To further improve the BSS performance, t-f grouping techniques are introduced to reduce the number of signals under consideration, and to allow the receiver array to separate more sources than the number of array sensors, provided that the sources have disjoint t-f signatures. With the use of one or more techniques proposed in this paper, improved performance of blind separation of nonstationary signals can be achieved.

  3. Application of particle swarm optimization blind source separation technology in fault diagnosis of gearbox

    Institute of Scientific and Technical Information of China (English)

    黄晋英; 潘宏侠; 毕世华; 杨喜旺

    2008-01-01

    Blind source separation (BBS) technology was applied to vibration signal processing of gearbox for separating different fault vibration sources and enhancing fault information. An improved BSS algorithm based on particle swarm optimization (PSO) was proposed. It can change the traditional fault-enhancing thought based on de-noising. And it can also solve the practical difficult problem of fault location and low fault diagnosis rate in early stage. It was applied to the vibration signal of gearbox under three working states. The result proves that the BSS greatly enhances fault information and supplies technological method for diagnosis of weak fault.

  4. RESEARCH OF QUANTUM GENETIC ALGORITH AND ITS APPLICATION IN BLIND SOURCE SEPARATION

    Institute of Scientific and Technical Information of China (English)

    YangJunan; LiBin; 等

    2003-01-01

    This letter proposes two algorithns:a novel Quantum Genetic Algorithm(QGA)based on the improvement of Han's Genetic Quantum Algorithm(GQA)and a new Blind Source Separation(BSS)method based on QGA and Independent Component Analysis(ICA).The simulation result shows that the efficiency of the new BSS nethod is obviously higher than that of the Conventional Genetic Algorithm(CGA).

  5. On the blind source separation of human electroencephalogram by approximate joint diagonalization of second order statistics

    OpenAIRE

    Congedo, Marco; Gouy-Pailler, Cedric; Jutten, Christian

    2008-01-01

    Over the last ten years blind source separation (BSS) has become a prominent processing tool in the study of human electroencephalography (EEG). Without relying on head modeling BSS aims at estimating both the waveform and the scalp spatial pattern of the intracranial dipolar current responsible of the observed EEG. In this review we begin by placing the BSS linear instantaneous model of EEG within the framework of brain volume conduction theory. We then review the concept and current practic...

  6. Gearbox Fault Diagnosis in a Wind Turbine Using Single Sensor Based Blind Source Separation

    Directory of Open Access Journals (Sweden)

    Yuning Qian

    2016-01-01

    Full Text Available This paper presents a single sensor based blind source separation approach, namely, the wavelet-assisted stationary subspace analysis (WSSA, for gearbox fault diagnosis in a wind turbine. Continuous wavelet transform (CWT is used as a preprocessing tool to decompose a single sensor measurement data into a set of wavelet coefficients to meet the multidimensional requirement of the stationary subspace analysis (SSA. The SSA is a blind source separation technique that can separate the multidimensional signals into stationary and nonstationary source components without the need for independency and prior information of the source signals. After that, the separated nonstationary source component with the maximum kurtosis value is analyzed by the enveloping spectral analysis to identify potential fault-related characteristic frequencies. Case studies performed on a wind turbine gearbox test system verify the effectiveness of the WSSA approach and indicate that it outperforms independent component analysis (ICA and empirical mode decomposition (EMD, as well as the spectral-kurtosis-based enveloping, for wind turbine gearbox fault diagnosis.

  7. Blind source separation of multichannel electroencephalogram based on wavelet transform and ICA

    Institute of Scientific and Technical Information of China (English)

    You Rong-Yi; Chen Zhong

    2005-01-01

    Combination of the wavelet transform and independent component analysis (ICA) was employed for blind source separation (BSS) of multichannel electroencephalogram (EEG). After denoising the original signals by discrete wavelet transform, high frequency components of some noises and artifacts were removed from the original signals. The denoised signals were reconstructed again for the purpose of ICA, such that the drawback that ICA cannot distinguish noises from source signals can be overcome effectively. The practical processing results showed that this method is an effective way to BSS of multichannel EEG. The method is actually a combination of wavelet transform with adaptive neural network, so it is also useful for BBS of other complex signals.

  8. Difficulties applying recent blind source separation techniques to EEG and MEG

    CERN Document Server

    Knuth, Kevin H

    2015-01-01

    High temporal resolution measurements of human brain activity can be performed by recording the electric potentials on the scalp surface (electroencephalography, EEG), or by recording the magnetic fields near the surface of the head (magnetoencephalography, MEG). The analysis of the data is problematic due to the fact that multiple neural generators may be simultaneously active and the potentials and magnetic fields from these sources are superimposed on the detectors. It is highly desirable to un-mix the data into signals representing the behaviors of the original individual generators. This general problem is called blind source separation and several recent techniques utilizing maximum entropy, minimum mutual information, and maximum likelihood estimation have been applied. These techniques have had much success in separating signals such as natural sounds or speech, but appear to be ineffective when applied to EEG or MEG signals. Many of these techniques implicitly assume that the source distributions hav...

  9. The Effectiveness of Blind Source Separation Using Independent Component Analysis for GNSS Time Series Analysis

    Science.gov (United States)

    Yan, Jun; Dong, Danan; Chen, Wen

    2016-04-01

    Due to the development of GNSS technology and the improvement of its positioning accuracy, observational data obtained by GNSS is widely used in Earth space geodesy and geodynamics research. Whereas the GNSS time series data of observation stations contains a plenty of information. This includes geographical space changes, deformation of the Earth, the migration of subsurface material, instantaneous deformation of the Earth, weak deformation and other blind signals. In order to decompose some instantaneous deformation underground, weak deformation and other blind signals hided in GNSS time series, we apply Independent Component Analysis (ICA) to daily station coordinate time series of the Southern California Integrated GPS Network. As ICA is based on the statistical characteristics of the observed signal. It uses non-Gaussian and independence character to process time series to obtain the source signal of the basic geophysical events. In term of the post-processing procedure of precise time-series data by GNSS, this paper examines GNSS time series using the principal component analysis (PCA) module of QOCA and ICA algorithm to separate the source signal. Then we focus on taking into account of these two signal separation technologies, PCA and ICA, for separating original signal that related geophysical disturbance changes from the observed signals. After analyzing these separation process approaches, we demonstrate that in the case of multiple factors, PCA exists ambiguity in the separation of source signals, that is the result related is not clear, and ICA will be better than PCA, which means that dealing with GNSS time series that the combination of signal source is unknown is suitable to use ICA.

  10. Underdetermined Blind Source Separation with Variational Mode Decomposition for Compound Roller Bearing Fault Signals.

    Science.gov (United States)

    Tang, Gang; Luo, Ganggang; Zhang, Weihua; Yang, Caijin; Wang, Huaqing

    2016-01-01

    In the condition monitoring of roller bearings, the measured signals are often compounded due to the unknown multi-vibration sources and complex transfer paths. Moreover, the sensors are limited in particular locations and numbers. Thus, this is a problem of underdetermined blind source separation for the vibration sources estimation, which makes it difficult to extract fault features exactly by ordinary methods in running tests. To improve the effectiveness of compound fault diagnosis in roller bearings, the present paper proposes a new method to solve the underdetermined problem and to extract fault features based on variational mode decomposition. In order to surmount the shortcomings of inadequate signals collected through limited sensors, a vibration signal is firstly decomposed into a number of band-limited intrinsic mode functions by variational mode decomposition. Then, the demodulated signal with the Hilbert transform of these multi-channel functions is used as the input matrix for independent component analysis. Finally, the compound faults are separated effectively by carrying out independent component analysis, which enables the fault features to be extracted more easily and identified more clearly. Experimental results validate the effectiveness of the proposed method in compound fault separation, and a comparison experiment shows that the proposed method has higher adaptability and practicability in separating strong noise signals than the commonly-used ensemble empirical mode decomposition method. PMID:27322268

  11. Underdetermined Blind Source Separation with Variational Mode Decomposition for Compound Roller Bearing Fault Signals

    Directory of Open Access Journals (Sweden)

    Gang Tang

    2016-06-01

    Full Text Available In the condition monitoring of roller bearings, the measured signals are often compounded due to the unknown multi-vibration sources and complex transfer paths. Moreover, the sensors are limited in particular locations and numbers. Thus, this is a problem of underdetermined blind source separation for the vibration sources estimation, which makes it difficult to extract fault features exactly by ordinary methods in running tests. To improve the effectiveness of compound fault diagnosis in roller bearings, the present paper proposes a new method to solve the underdetermined problem and to extract fault features based on variational mode decomposition. In order to surmount the shortcomings of inadequate signals collected through limited sensors, a vibration signal is firstly decomposed into a number of band-limited intrinsic mode functions by variational mode decomposition. Then, the demodulated signal with the Hilbert transform of these multi-channel functions is used as the input matrix for independent component analysis. Finally, the compound faults are separated effectively by carrying out independent component analysis, which enables the fault features to be extracted more easily and identified more clearly. Experimental results validate the effectiveness of the proposed method in compound fault separation, and a comparison experiment shows that the proposed method has higher adaptability and practicability in separating strong noise signals than the commonly-used ensemble empirical mode decomposition method.

  12. AN EME BLIND SOURCE SEPARATION ALGORITHM BASED ON GENERALIZED EXPONENTIAL FUNCTION

    Institute of Scientific and Technical Information of China (English)

    Miao Hao; Li Xiaodong; Tian Jing

    2008-01-01

    This letter investigates an improved blind source separation algorithm based on Maximum Entropy (ME) criteria. The original ME algorithm chooses the fixed exponential or sigmoid function as the nonlinear mapping function which can not match the original signal very well. A parameter estimation method is employed in this letter to approach the probability of density function of any signal with parameter-steered generalized exponential function. An improved learning rule and a natural gradient update formula of unmixing matrix are also presented. The algorithm of this letter can separate the mixture of super-Gaussian signals and also the mixture of sub-Gaussian signals. The simulation experiment demonstrates the efficiency of the algorithm.

  13. Natural gradient-based recursive least-squares algorithm for adaptive blind source separation

    Institute of Scientific and Technical Information of China (English)

    ZHU Xiaolong; ZHANG Xianda; YE Jimin

    2004-01-01

    This paper focuses on the problem of adaptive blind source separation (BSS).First, a recursive least-squares (RLS) whitening algorithm is proposed. By combining it with a natural gradient-based RLS algorithm for nonlinear principle component analysis (PCA), and using reasonable approximations, a novel RLS algorithm which can achieve BSS without additional pre-whitening of the observed mixtures is obtained. Analyses of the equilibrium points show that both of the RLS whitening algorithm and the natural gradient-based RLS algorithm for BSS have the desired convergence properties. It is also proved that the combined new RLS algorithm for BSS is equivariant and has the property of keeping the separating matrix from becoming singular. Finally, the effectiveness of the proposed algorithm is verified by extensive simulation results.

  14. Generic Uniqueness of a Structured Matrix Factorization and Applications in Blind Source Separation

    Science.gov (United States)

    Domanov, Ignat; Lathauwer, Lieven De

    2016-06-01

    Algebraic geometry, although little explored in signal processing, provides tools that are very convenient for investigating generic properties in a wide range of applications. Generic properties are properties that hold "almost everywhere". We present a set of conditions that are sufficient for demonstrating the generic uniqueness of a certain structured matrix factorization. This set of conditions may be used as a checklist for generic uniqueness in different settings. We discuss two particular applications in detail. We provide a relaxed generic uniqueness condition for joint matrix diagonalization that is relevant for independent component analysis in the underdetermined case. We present generic uniqueness conditions for a recently proposed class of deterministic blind source separation methods that rely on mild source models. For the interested reader we provide some intuition on how the results are connected to their algebraic geometric roots.

  15. Detection of sudden structural damage using blind source separation and time-frequency approaches

    Science.gov (United States)

    Morovati, V.; Kazemi, M. T.

    2016-05-01

    Seismic signal processing is one of the most reliable methods of detecting the structural damage during earthquakes. In this paper, the use of the hybrid method of blind source separation (BSS) and time-frequency analysis (TFA) is explored to detect the changes in the structural response data. The combination of the BSS and TFA is applied to the seismic signals due to the non-stationary nature of them. Firstly, the second-order blind identification technique is used to decompose the response signal of structural vibration into modal coordinate signals which will be mono-components for TFA. Then each mono-component signal is analyzed to extract instantaneous frequency of structure. Numerical simulations and a real-world seismic-excited structure with time-varying frequencies show the accuracy and robustness of the developed algorithm. TFA of extracted sources shows that used method can be successfully applied to structural damage detection. The results also demonstrate that the combined method can be used to identify the time instant of structural damage occurrence more sharply and effectively than by the use of TFA alone.

  16. Temporal Unmixing of Dynamic Fluorescent Images by Blind Source Separation Method with a Convex Framework

    Directory of Open Access Journals (Sweden)

    Duofang Chen

    2015-01-01

    Full Text Available By recording a time series of tomographic images, dynamic fluorescence molecular tomography (FMT allows exploring perfusion, biodistribution, and pharmacokinetics of labeled substances in vivo. Usually, dynamic tomographic images are first reconstructed frame by frame, and then unmixing based on principle component analysis (PCA or independent component analysis (ICA is performed to detect and visualize functional structures with different kinetic patterns. PCA and ICA assume sources are statistically uncorrelated or independent and don’t perform well when correlated sources are present. In this paper, we deduce the relationship between the measured imaging data and the kinetic patterns and present a temporal unmixing approach, which is based on nonnegative blind source separation (BSS method with a convex analysis framework to separate the measured data. The presented method requires no assumption on source independence or zero correlations. Several numerical simulations and phantom experiments are conducted to investigate the performance of the proposed temporal unmixing method. The results indicate that it is feasible to unmix the measured data before the tomographic reconstruction and the BSS based method provides better unmixing quality compared with PCA and ICA.

  17. Non-Cancellation Multistage Kurtosis Maximization with Prewhitening for Blind Source Separation

    Directory of Open Access Journals (Sweden)

    Xiang Chen

    2009-01-01

    Full Text Available Chi et al. recently proposed two effective non-cancellation multistage (NCMS blind source separation algorithms, one using the turbo source extraction algorithm (TSEA, called the NCMS-TSEA, and the other using the fast kurtosis maximization algorithm (FKMA, called the NCMS-FKMA. Their computational complexity and performance heavily depend on the dimension of multisensor data, that is, number of sensors. This paper proposes the inclusion of the prewhitening processing in the NCMS-TSEA and NCMS-FKMA prior to source extraction. We come up with four improved algorithms, referred to as the PNCMS-TSEA, the PNCMS-FKMA, the PNCMS-TSEA(p, and the PNCMS-FKMA(p. Compared with the existing NCMS-TSEA and NCMS-FKMA, the former two algorithms perform with significant computational complexity reduction and some performance improvements. The latter two algorithms are generalized counterparts of the former two algorithms with the single source extraction module replaced by a bank of source extraction modules in parallel at each stage. In spite of the same performance of PNCMS-TSEA and PNCMS-TSEA(p (PNCMS-FKMA and PNCMS-FKMA(p, the merit of this parallel source extraction structure lies in much shorter processing latency making the PNCMS-TSEA(p and PNCMS-FKMA(p well suitable for software and hardware implementations. Some simulation results are presented to verify the efficacy and computational efficiency of the proposed algorithms.

  18. Time-Domain Convolutive Blind Source Separation Employing Selective-Tap Adaptive Algorithms

    Directory of Open Access Journals (Sweden)

    Pan Qiongfeng

    2007-01-01

    Full Text Available We investigate novel algorithms to improve the convergence and reduce the complexity of time-domain convolutive blind source separation (BSS algorithms. First, we propose MMax partial update time-domain convolutive BSS (MMax BSS algorithm. We demonstrate that the partial update scheme applied in the MMax LMS algorithm for single channel can be extended to multichannel time-domain convolutive BSS with little deterioration in performance and possible computational complexity saving. Next, we propose an exclusive maximum selective-tap time-domain convolutive BSS algorithm (XM BSS that reduces the interchannel coherence of the tap-input vectors and improves the conditioning of the autocorrelation matrix resulting in improved convergence rate and reduced misalignment. Moreover, the computational complexity is reduced since only half of the tap inputs are selected for updating. Simulation results have shown a significant improvement in convergence rate compared to existing techniques.

  19. Time-Domain Convolutive Blind Source Separation Employing Selective-Tap Adaptive Algorithms

    Directory of Open Access Journals (Sweden)

    Qiongfeng Pan

    2007-04-01

    Full Text Available We investigate novel algorithms to improve the convergence and reduce the complexity of time-domain convolutive blind source separation (BSS algorithms. First, we propose MMax partial update time-domain convolutive BSS (MMax BSS algorithm. We demonstrate that the partial update scheme applied in the MMax LMS algorithm for single channel can be extended to multichannel time-domain convolutive BSS with little deterioration in performance and possible computational complexity saving. Next, we propose an exclusive maximum selective-tap time-domain convolutive BSS algorithm (XM BSS that reduces the interchannel coherence of the tap-input vectors and improves the conditioning of the autocorrelation matrix resulting in improved convergence rate and reduced misalignment. Moreover, the computational complexity is reduced since only half of the tap inputs are selected for updating. Simulation results have shown a significant improvement in convergence rate compared to existing techniques.

  20. PWC-ICA: A Method for Stationary Ordered Blind Source Separation with Application to EEG

    Science.gov (United States)

    Bigdely-Shamlo, Nima; Mullen, Tim; Robbins, Kay

    2016-01-01

    Independent component analysis (ICA) is a class of algorithms widely applied to separate sources in EEG data. Most ICA approaches use optimization criteria derived from temporal statistical independence and are invariant with respect to the actual ordering of individual observations. We propose a method of mapping real signals into a complex vector space that takes into account the temporal order of signals and enforces certain mixing stationarity constraints. The resulting procedure, which we call Pairwise Complex Independent Component Analysis (PWC-ICA), performs the ICA in a complex setting and then reinterprets the results in the original observation space. We examine the performance of our candidate approach relative to several existing ICA algorithms for the blind source separation (BSS) problem on both real and simulated EEG data. On simulated data, PWC-ICA is often capable of achieving a better solution to the BSS problem than AMICA, Extended Infomax, or FastICA. On real data, the dipole interpretations of the BSS solutions discovered by PWC-ICA are physically plausible, are competitive with existing ICA approaches, and may represent sources undiscovered by other ICA methods. In conjunction with this paper, the authors have released a MATLAB toolbox that performs PWC-ICA on real, vector-valued signals. PMID:27340397

  1. Separation of combustion noise and piston-slap in diesel engine—Part II: Separation of combustion noise and piston-slap using blind source separation methods

    Science.gov (United States)

    Servière, C.; Lacoume, J.-L.; El Badaoui, M.

    2005-11-01

    This paper is devoted to blind separation of combustion noise and piston-slap in diesel engines. The two phenomena are recovered only from signals issued from accelerometers placed on one of the cylinders. A blind source separation (BSS) method is developed, based on a convolutive model of non-stationary mixtures. We introduce a new method based on the joint diagonalisation of the time varying spectral matrices of the observation records and a new technique to handle the problem of permutation ambiguity in the frequency domain. This method is then applied to real data and the estimated sources are validated by several physical arguments. So, the contribution of the piston-slap and the combustion noise can be recovered for all the sensors. The energy of the two phenomena can then be given with regards to the position of the accelerometers.

  2. Advances in blind source separation (BSS) and independent component analysis (ICA) for nonlinear mixtures.

    Science.gov (United States)

    Jutten, Christian; Karhunen, Juha

    2004-10-01

    In this paper, we review recent advances in blind source separation (BSS) and independent component analysis (ICA) for nonlinear mixing models. After a general introduction to BSS and ICA, we discuss in more detail uniqueness and separability issues, presenting some new results. A fundamental difficulty in the nonlinear BSS problem and even more so in the nonlinear ICA problem is that they provide non-unique solutions without extra constraints, which are often implemented by using a suitable regularization. In this paper, we explore two possible approaches. The first one is based on structural constraints. Especially, post-nonlinear mixtures are an important special case, where a nonlinearity is applied to linear mixtures. For such mixtures, the ambiguities are essentially the same as for the linear ICA or BSS problems. The second approach uses Bayesian inference methods for estimating the best statistical parameters, under almost unconstrained models in which priors can be easily added. In the later part of this paper, various separation techniques proposed for post-nonlinear mixtures and general nonlinear mixtures are reviewed. PMID:15593377

  3. System identification through nonstationary data using Time-Frequency Blind Source Separation

    Science.gov (United States)

    Guo, Yanlin; Kareem, Ahsan

    2016-06-01

    Classical output-only system identification (SI) methods are based on the assumption of stationarity of the system response. However, measured response of buildings and bridges is usually non-stationary due to strong winds (e.g. typhoon, and thunder storm etc.), earthquakes and time-varying vehicle motions. Accordingly, the response data may have time-varying frequency contents and/or overlapping of modal frequencies due to non-stationary colored excitation. This renders traditional methods problematic for modal separation and identification. To address these challenges, a new SI technique based on Time-Frequency Blind Source Separation (TFBSS) is proposed. By selectively utilizing "effective" information in local regions of the time-frequency plane, where only one mode contributes to energy, the proposed technique can successfully identify mode shapes and recover modal responses from the non-stationary response where the traditional SI methods often encounter difficulties. This technique can also handle response with closely spaced modes which is a well-known challenge for the identification of large-scale structures. Based on the separated modal responses, frequency and damping can be easily identified using SI methods based on a single degree of freedom (SDOF) system. In addition to the exclusive advantage of handling non-stationary data and closely spaced modes, the proposed technique also benefits from the absence of the end effects and low sensitivity to noise in modal separation. The efficacy of the proposed technique is demonstrated using several simulation based studies, and compared to the popular Second-Order Blind Identification (SOBI) scheme. It is also noted that even some non-stationary response data can be analyzed by the stationary method SOBI. This paper also delineates non-stationary cases where SOBI and the proposed scheme perform comparably and highlights cases where the proposed approach is more advantageous. Finally, the performance of the

  4. Nonnegative Matrix Factor 2-D Deconvolution for Blind Single Channel Source Separation

    DEFF Research Database (Denmark)

    Schmidt, Mikkel N.; Mørup, Morten

    2006-01-01

    We present a novel method for blind separation of instruments in polyphonic music based on a non-negative matrix factor 2-D deconvolution algorithm. Using a model which is convolutive in both time and frequency we factorize a spectrogram representation of music into components corresponding to...... individual instruments. Based on this factorization we separate the instruments using spectrogram masking. The proposed algorithm has applications in computational auditory scene analysis, music information retrieval, and automatic music transcription....

  5. Feature Selection and Blind Source Separation in an EEG-Based Brain-Computer Interface

    Directory of Open Access Journals (Sweden)

    Michael H. Thaut

    2005-11-01

    Full Text Available Most EEG-based BCI systems make use of well-studied patterns of brain activity. However, those systems involve tasks that indirectly map to simple binary commands such as “yes” or “no” or require many weeks of biofeedback training. We hypothesized that signal processing and machine learning methods can be used to discriminate EEG in a direct “yes”/“no” BCI from a single session. Blind source separation (BSS and spectral transformations of the EEG produced a 180-dimensional feature space. We used a modified genetic algorithm (GA wrapped around a support vector machine (SVM classifier to search the space of feature subsets. The GA-based search found feature subsets that outperform full feature sets and random feature subsets. Also, BSS transformations of the EEG outperformed the original time series, particularly in conjunction with a subset search of both spaces. The results suggest that BSS and feature selection can be used to improve the performance of even a “direct,” single-session BCI.

  6. Penerapan Teknik Blind Source Separation untuk Memisahkan Noise dari Sinyal Akustik yang Non Gaussian

    Directory of Open Access Journals (Sweden)

    Farkhan Rosi

    2013-09-01

    Full Text Available Pada sistem komunikasi bawah air, seringkali sinyal yang diterima oleh sensor berasal dari hasil pencampuran sumber sinyal dengan sinyal-sinyal akustik lain di lingkungan bawah air. Hal ini menjadikan sinyal yang didapatkan menjadi tidak sesuai dengan yang diinginkan. Teknik Blind Source Separation (BSS dipakai di sini untuk memisahkan sinyal-sinyal yang bercampur tersebut. Dalam tugas akhir ini, dilakukan pemisahan sinyal akustik dengan menggunakan Natural Gradient ICA berdasarkan Generalized Gaussian Model yang didapat dari karakteristik distribusi sumber sinyal akustik non-gaussian yakni ship radiated noise dan sea ambient noise. Pemisahan sinyal akustik dilakukan sebanyak tiga kali yakni dengan simulasi, toolbox ICALABS V3, dan menggunakan pemisahan sinyal akustik dari data riil pengukuran. Dari hasil simulasi menunjukkan pemisahan dengan algoritma Natural Gradien ICA berdasarkan Generalized Gaussian Model berjalan dengan baik. Hal ini ditunjukkan dengan nilai SIR shrimp.wav = 48.9946 dB dan ferry.wav = 46.9309. dB. Sedangkan rata-rata MSE shrimp.wav = 1.2605 x 10-5 dan ferry.wav = 2.0272 x 10 -5.

  7. Powerline noise elimination in biomedical signals via blind source separation and wavelet analysis

    Directory of Open Access Journals (Sweden)

    Samuel Akwei-Sekyere

    2015-07-01

    Full Text Available The distortion of biomedical signals by powerline noise from recording biomedical devices has the potential to reduce the quality and convolute the interpretations of the data. Usually, powerline noise in biomedical recordings are extinguished via band-stop filters. However, due to the instability of biomedical signals, the distribution of signals filtered out may not be centered at 50/60 Hz. As a result, self-correction methods are needed to optimize the performance of these filters. Since powerline noise is additive in nature, it is intuitive to model powerline noise in a raw recording and subtract it from the raw data in order to obtain a relatively clean signal. This paper proposes a method that utilizes this approach by decomposing the recorded signal and extracting powerline noise via blind source separation and wavelet analysis. The performance of this algorithm was compared with that of a 4th order band-stop Butterworth filter, empirical mode decomposition, independent component analysis and, a combination of empirical mode decomposition with independent component analysis. The proposed method was able to expel sinusoidal signals within powerline noise frequency range with higher fidelity in comparison with the mentioned techniques, especially at low signal-to-noise ratio.

  8. Towards damage detection using blind source separation integrated with time-varying auto-regressive modeling

    Science.gov (United States)

    Musafere, F.; Sadhu, A.; Liu, K.

    2016-01-01

    In the last few decades, structural health monitoring (SHM) has been an indispensable subject in the field of vibration engineering. With the aid of modern sensing technology, SHM has garnered significant attention towards diagnosis and risk management of large-scale civil structures and mechanical systems. In SHM, system identification is one of major building blocks through which unknown system parameters are extracted from vibration data of the structures. Such system information is then utilized to detect the damage instant, and its severity to rehabilitate and prolong the existing health of the structures. In recent years, blind source separation (BSS) algorithm has become one of the newly emerging advanced signal processing techniques for output-only system identification of civil structures. In this paper, a novel damage detection technique is proposed by integrating BSS with the time-varying auto-regressive modeling to identify the instant and severity of damage. The proposed method is validated using a suite of numerical studies and experimental models followed by a full-scale structure.

  9. A Semi-Blind Source Separation Method for Differential Optical Absorption Spectroscopy of Atmospheric Gas Mixtures

    CERN Document Server

    Sun, Y; Finlayson-Pitts, B J; Xin, J

    2011-01-01

    Differential optical absorption spectroscopy (DOAS) is a powerful tool for detecting and quantifying trace gases in atmospheric chemistry \\cite{Platt_Stutz08}. DOAS spectra consist of a linear combination of complex multi-peak multi-scale structures. Most DOAS analysis routines in use today are based on least squares techniques, for example, the approach developed in the 1970s uses polynomial fits to remove a slowly varying background, and known reference spectra to retrieve the identity and concentrations of reference gases. An open problem is to identify unknown gases in the fitting residuals for complex atmospheric mixtures. In this work, we develop a novel three step semi-blind source separation method. The first step uses a multi-resolution analysis to remove the slow-varying and fast-varying components in the DOAS spectral data matrix $X$. The second step decomposes the preprocessed data $\\hat{X}$ in the first step into a linear combination of the reference spectra plus a remainder, or $\\hat{X} = A\\,S +...

  10. Blind Source Separation of Hemodynamics from Magnetic Resonance Perfusion Brain Images Using Independent Factor Analysis

    Directory of Open Access Journals (Sweden)

    Yen-Chun Chou

    2010-01-01

    Full Text Available Perfusion magnetic resonance brain imaging induces temporal signal changes on brain tissues, manifesting distinct blood-supply patterns for the profound analysis of cerebral hemodynamics. We employed independent factor analysis to blindly separate such dynamic images into different maps, that is, artery, gray matter, white matter, vein and sinus, and choroid plexus, in conjunction with corresponding signal-time curves. The averaged signal-time curve on the segmented arterial area was further used to calculate the relative cerebral blood volume (rCBV, relative cerebral blood flow (rCBF, and mean transit time (MTT. The averaged ratios for rCBV, rCBF, and MTT between gray and white matters for normal subjects were congruent with those in the literature.

  11. Tracking Signal Subspace Invariance for Blind Separation and Classification of Nonorthogonal Sources in Correlated Noise

    Science.gov (United States)

    Oweiss, Karim G.; Anderson, David J.

    2006-12-01

    We investigate a new approach for the problem of source separation in correlated multichannel signal and noise environments. The framework targets the specific case when nonstationary correlated signal sources contaminated by additive correlated noise impinge on an array of sensors. Existing techniques targeting this problem usually assume signal sources to be independent, and the contaminating noise to be spatially and temporally white, thus enabling orthogonal signal and noise subspaces to be separated using conventional eigendecomposition. In our context, we propose a solution to the problem when the sources are nonorthogonal, and the noise is correlated with an unknown temporal and spatial covariance. The approach is based on projecting the observations onto a nested set of multiresolution spaces prior to eigendecomposition. An inherent invariance property of the signal subspace is observed in a subset of the multiresolution spaces that depends on the degree of approximation expressed by the orthogonal basis. This feature, among others revealed by the algorithm, is eventually used to separate the signal sources in the context of "best basis" selection. The technique shows robustness to source nonstationarities as well as anisotropic properties of the unknown signal propagation medium under no constraints on the array design, and with minimal assumptions about the underlying signal and noise processes. We illustrate the high performance of the technique on simulated and experimental multichannel neurophysiological data measurements.

  12. Extraction for fetal ECG using single channel blind source separation algorithm based on multi-algorithm fusion

    Directory of Open Access Journals (Sweden)

    He Peng Ju

    2016-01-01

    Full Text Available Nowadays, detecting fetal ECG using abdominal signal is a commonly used method, but fetal ECG signal will be affected by maternal ECG. Current FECG extraction algorithms are mainly aiming at multiple channels signal. They often assume there is only one fetus and did not consider multiple births. This paper proposed a single channel blind source separation (SCBSS algorithm based on source number estimation using multi-algorithm fusion to process single abdominal signal. The method decomposed collected single channel signal into multiple intrinsic mode function (IMF utilizing Empirical Mode Decomposition (EMD, mapping single channel into multiple channels. Four multiple channel source number estimation (MCSNE methods (Bootstrap, Hough, AIC and PCA were weighting fused to estimate accurate source number and the particle swarm optimization algorithm (PSO was employed to determine weighted coefficient. According to source number and IMF, nonnegative matrix was constructed and nonnegative matrix factorization (NMF was employed to separate mixed signals. Experiments used single channel signal mixed by four man-made signals and single channel ECG mixed by two to verify the proposed algorithm. Results showed that the proposed algorithm could determine number of independent signal in single acquired signal. FECG could be extracted from single channel observed signal and the algorithm can be used to solve separation of MECG and FECG.

  13. Blind source separation based on time-frequency morphological characteristics for rigid acoustic scattering by underwater objects

    Science.gov (United States)

    Yang, Yang; Li, Xiukun

    2016-06-01

    Separation of the components of rigid acoustic scattering by underwater objects is essential in obtaining the structural characteristics of such objects. To overcome the problem of rigid structures appearing to have the same spectral structure in the time domain, time-frequency Blind Source Separation (BSS) can be used in combination with image morphology to separate the rigid scattering components of different objects. Based on a highlight model, the separation of the rigid scattering structure of objects with time-frequency distribution is deduced. Using a morphological filter, different characteristics in a Wigner-Ville Distribution (WVD) observed for single auto term and cross terms can be simplified to remove any cross-term interference. By selecting time and frequency points of the auto terms signal, the accuracy of BSS can be improved. An experimental simulation has been used, with changes in the pulse width of the transmitted signal, the relative amplitude and the time delay parameter, in order to analyzing the feasibility of this new method. Simulation results show that the new method is not only able to separate rigid scattering components, but can also separate the components when elastic scattering and rigid scattering exist at the same time. Experimental results confirm that the new method can be used in separating the rigid scattering structure of underwater objects.

  14. 稀疏盲源分离快速算法%A Fast Algorithm for Blind Sparse Source Separation

    Institute of Scientific and Technical Information of China (English)

    董天宝; 杨景曙

    2012-01-01

    In this paper, a fast algorithm for blind sparse source separation is proposed. Sources are estimated by means of minimizing (0-norm which is approximated using a predefined continuous and differentiable function. The proposed algorithm is easy to implement and runs fast. Then the algorithm is compared with several fast sparse reconstruction algorithms such as fast (1-norm minimization algorithm and OMP using synthetic data. Finally, we apply the proposed algorithm to underdetermined blind source separation using real world data. It is experimentally shown that the proposed algorithm runs faster than other algorithms, while acquiring almost the same (or better) quality.%提出一种快速的稀疏信号重构算法,通过定义一个连续可微函数近似l0范数,采用最小化l0范数的方法实现对稀疏源信号的估计.该算法的特点是实现简单,速度快.采用人工生成的信号将算法与通过l1范数最小化的快速稀疏信号重构算法和OMP算法进行了比较.最后,将该算法用于实际信号的欠定盲源分离.仿真实验表明,算法在保证信号分离性能的前提下大幅度提高了算法的运行速度.

  15. Time-domain beamforming and blind source separation speech input in the car environment

    CERN Document Server

    Bourgeois, Julien

    2009-01-01

    The development of computer and telecommunication technologies led to a revolutioninthewaythatpeopleworkandcommunicatewitheachother.One of the results is that large amount of information will increasingly be held in a form that is natural for users, as speech in natural language. In the presented work, we investigate the speech signal capture problem, which includes the separation of multiple interfering speakers using microphone arrays. Adaptive beamforming is a classical approach which has been developed since the seventies. However it requires a double-talk detector (DTD) that interrupts th

  16. MAP-Based Underdetermined Blind Source Separation of Convolutive Mixtures by Hierarchical Clustering and -Norm Minimization

    Directory of Open Access Journals (Sweden)

    Kellermann Walter

    2007-01-01

    Full Text Available We address the problem of underdetermined BSS. While most previous approaches are designed for instantaneous mixtures, we propose a time-frequency-domain algorithm for convolutive mixtures. We adopt a two-step method based on a general maximum a posteriori (MAP approach. In the first step, we estimate the mixing matrix based on hierarchical clustering, assuming that the source signals are sufficiently sparse. The algorithm works directly on the complex-valued data in the time-frequency domain and shows better convergence than algorithms based on self-organizing maps. The assumption of Laplacian priors for the source signals in the second step leads to an algorithm for estimating the source signals. It involves the -norm minimization of complex numbers because of the use of the time-frequency-domain approach. We compare a combinatorial approach initially designed for real numbers with a second-order cone programming (SOCP approach designed for complex numbers. We found that although the former approach is not theoretically justified for complex numbers, its results are comparable to, or even better than, the SOCP solution. The advantage is a lower computational cost for problems with low input/output dimensions.

  17. The Application of Compressed Sensing in Blind Source Separation%压缩感知原理在盲信号分离中的应用

    Institute of Scientific and Technical Information of China (English)

    王涛文

    2012-01-01

    Compressed Sensing has been a new signal sampling theory in recent years, for it overcomes the high rate of sampling defects of traditional Nyquist signal sampling theory, It presented the basic principles of Compressed Sensing, introduced three fundamental questions of Compressed Sensing-the sparse-ness of signals 、irrelevance between sparse matrix and measurement matrix, and reconstruction of the signals, and analyzed the contact between Compressed Sensing and Blind Source Separation. Then, it offered a new way to solve the problem of Blind Source Separation. Finally, through the experiment it showed its application in Blind Source Separation.%主要阐述了压缩感知的基本原理,介绍了压缩感知的3个基本问题:信号的稀疏表示、稀疏基与测量矩阵的不相关性和信号的重构,分析了它与盲信号分离之间的联系,为解决盲信号分离问题提供了一个新的途径.最后通过具体实验说明它在盲信号分离上的应用.

  18. System approach to robust acoustic echo cancellation through semi-blind source separation based on independent component analysis

    Science.gov (United States)

    Wada, Ted S.

    In this dissertation, we build a foundation for what we refer to as the system approach to signal enhancement as we focus on the acoustic echo cancellation (AEC) problem. Such a “system” perspective aims for the integration of individual components, or algorithms, into a cohesive unit for the benefit of the system as a whole to cope with real-world enhancement problems. The standard system identification approach by minimizing the mean square error (MSE) of a linear system is sensitive to distortions that greatly affect the quality of the identification result. Therefore, we begin by examining in detail the technique of using a noise-suppressing nonlinearity in the adaptive filter error feedback-loop of the LMS algorithm when there is an interference at the near end, where the source of distortion may be linear or nonlinear. We provide a thorough derivation and analysis of the error recovery nonlinearity (ERN) that “enhances” the filter estimation error prior to the adaptation to transform the corrupted error’s distribution into a desired one, or very close to it, in order to assist the linear adaptation process. We reveal important connections of the residual echo enhancement (REE) technique to other existing AEC and signal enhancement procedures, where the technique is well-founded in the information-theoretic sense and has strong ties to independent component analysis (ICA), which is the basis for blind source separation (BSS) that permits unsupervised adaptation in the presence of multiple interfering signals. Notably, the single-channel AEC problem can be viewed as a special case of semi-blind source separation (SBSS) where one of the source signals is partially known, i.e., the far-end microphone signal that generates the near-end acoustic echo. Indeed, SBSS optimized via ICA leads to the system combination of the LMS algorithm with the ERN that allows continuous and stable adaptation even during double talk. Next, we extend the system perspective

  19. 利用盲源分离算法实现DOA估计%DOA estimation method based on blind source separation algorithm

    Institute of Scientific and Technical Information of China (English)

    徐先峰; 刘义艳; 段晨东

    2012-01-01

    A new DOA (direction-of-arrival) estimation method based on an algorithm for fast blind source separation (FBSS-DOA) is proposed in this paper. A group of correlation matrices possessing diagonal structure is generated. A cost function of joint diagonalization for blind source separation is introduced. For solving this cost function, a fast multiplied iterative algorithm in complex-valued domain is utilized. The demixing matrix was then estimated and the estimation of DOA was realized. Compared with familiar algorithms, the algorithm has more generality and better estimation performance. The simulation results illustrate its efficiency.%提出一种基于快速盲源分离算法实现波达方向(DOA)估计的方法.构造了具有对角化结构的相关矩阵组,引入解盲源分离问题的联合对角化代价函数,采用一种快速的复数域乘性迭代算法求解代价函数,得到混迭矩阵逆的估计,进而实现DOA估计.与同类算法相比,该算法具有更广的适用性和更精确的DOA估计性能.仿真实验结果验证了算法的快速收敛性和优越的估计性能.

  20. New algorithm for underdetermined blind source separation%一种欠定盲源分离新算法

    Institute of Scientific and Technical Information of China (English)

    董天宝; 杨景曙

    2012-01-01

    A new two-step algorithm for underdetermined source separation is proposed. Mixing matrix is estimated using clustering methods. Sources are estimated using a fast sparse reconstructed algorithm which defines a continuous and differential function so as to approximate ∮° -norm. The new algorithm runs fast and is easily implemented. It is experimentally shown that the proposed algorithm runs faster than other two underdetermined source separation algorithms using fast minimization ∮1 -norm and OMP methods, while acquiring almost the same quality.%提出了一种基于两步法的欠定盲源分离新算法.在混合矩阵估计阶段,采用基于势函数的聚类方法,在源信号恢复阶段,提出一种快速的稀疏信号重构算法,通过定义一个连续可微函数来近似l0范数,使得l0范数可解.该算法的特点是实现简单、速度快.仿真实验表明,与现有的采用快速l1范数最小化和OMP算法的欠定盲源分离方法相比,提出的算法在保证分离性能的前提下大幅度提高了算法的运行速度.

  1. ITERATIVE MULTICHANNEL BLIND DECONVOLUTION METHOD FOR TEMPORALLY COLORED SOURCES

    Institute of Scientific and Technical Information of China (English)

    Zhang Mingjian; Wei Gang

    2004-01-01

    An iterative separation approach, i.e. source signals are extracted and removed one by one, is proposed for multichannel blind deconvolution of colored signals. Each source signal is extracted in two stages: a filtered version of the source signal is first obtained by solving the generalized eigenvalue problem, which is then followed by a single channel blind deconvolution based on ensemble learning. Simulation demonstrates the capability of the approach to perform efficient mutichannel blind deconvolution.

  2. A Novel Blind Source Separation Algorithm and Performance Analysis of Weak Signal against Strong Interference in Passive Radar Systems

    Directory of Open Access Journals (Sweden)

    Chengjie Li

    2016-01-01

    Full Text Available In Passive Radar System, obtaining the mixed weak object signal against the super power signal (jamming is still a challenging task. In this paper, a novel framework based on Passive Radar System is designed for weak object signal separation. Firstly, we propose an Interference Cancellation algorithm (IC-algorithm to extract the mixed weak object signals from the strong jamming. Then, an improved FastICA algorithm with K-means cluster is designed to separate each weak signal from the mixed weak object signals. At last, we discuss the performance of the proposed method and verify the novel method based on several simulations. The experimental results demonstrate the effectiveness of the proposed method.

  3. A New Method of Blind Source Separation Using Single-Channel ICA Based on Higher-Order Statistics

    OpenAIRE

    Guangkuo Lu; Manlin Xiao; Ping Wei; Huaguo Zhang

    2015-01-01

    Methods of utilizing independent component analysis (ICA) give little guidance about practical considerations for separating single-channel real-world data, in which most of them are nonlinear, nonstationary, and even chaotic in many fields. To solve this problem, a three-step method is provided in this paper. In the first step, the measured signal which is assumed to be piecewise higher order stationary time series is introduced and divided into a series of higher order stationary segments b...

  4. MAP-Based Underdetermined Blind Source Separation of Convolutive Mixtures by Hierarchical Clustering and ℓ1-Norm Minimization

    Directory of Open Access Journals (Sweden)

    Hiroshi Sawada

    2007-01-01

    Full Text Available We address the problem of underdetermined BSS. While most previous approaches are designed for instantaneous mixtures, we propose a time-frequency-domain algorithm for convolutive mixtures. We adopt a two-step method based on a general maximum a posteriori (MAP approach. In the first step, we estimate the mixing matrix based on hierarchical clustering, assuming that the source signals are sufficiently sparse. The algorithm works directly on the complex-valued data in the time-frequency domain and shows better convergence than algorithms based on self-organizing maps. The assumption of Laplacian priors for the source signals in the second step leads to an algorithm for estimating the source signals. It involves the ℓ1-norm minimization of complex numbers because of the use of the time-frequency-domain approach. We compare a combinatorial approach initially designed for real numbers with a second-order cone programming (SOCP approach designed for complex numbers. We found that although the former approach is not theoretically justified for complex numbers, its results are comparable to, or even better than, the SOCP solution. The advantage is a lower computational cost for problems with low input/output dimensions.

  5. 单观测通道船舶辐射噪声盲源分离%Blind source separation of ship-radiated noise using single observing channel

    Institute of Scientific and Technical Information of China (English)

    刘佳; 杨士莪; 朴胜春; 黄益旺

    2011-01-01

    提出了一种适用于单观测通道的船舶辐射噪声盲源分离方法.该方法依据船舶辐射噪声远场的空间分布规律,通过将单观测通道延时和滤波的方法构造虚拟通道,使单通道转化为多通道,以实现单通道的盲源分离.仿真及实验数据分析的结果显示,分离后信号的相关系数在不同信噪比下有稳定的提高,说明该方法能在一定程度上利用单观测通道在海洋环境噪声背景下分离船舶辐射噪声,实验数据分析同时表明该方法对双目标船的分离也有一定效果.%A method of blind source separation for ship-radiated noise is proposed based on single observing channel.According to the spatial characteristic of ship-radiated noise in far field, a virtual channel is constructed from the observed channel by time delay and data filtering. It overcomes the limitation of channel numbers. The simulation and experimental results using this method are presented. The results show that under the sea ambient noise the shipradiated noise can be separated by this method with single observing channel, and it is effective for two object ships to be separated.

  6. A New Method of Blind Source Separation Using Single-Channel ICA Based on Higher-Order Statistics

    Directory of Open Access Journals (Sweden)

    Guangkuo Lu

    2015-01-01

    Full Text Available Methods of utilizing independent component analysis (ICA give little guidance about practical considerations for separating single-channel real-world data, in which most of them are nonlinear, nonstationary, and even chaotic in many fields. To solve this problem, a three-step method is provided in this paper. In the first step, the measured signal which is assumed to be piecewise higher order stationary time series is introduced and divided into a series of higher order stationary segments by applying a modified segmentation algorithm. Then the state space is reconstructed and the single-channel signal is transformed into a pseudo multiple input multiple output (MIMO mode using a method of nonlinear analysis based on the high order statistics (HOS. In the last step, ICA is performed on the pseudo MIMO data to decompose the single channel recording into its underlying independent components (ICs and the interested ICs are then extracted. Finally, the effectiveness and excellence of the higher order single-channel ICA (SCICA method are validated with measured data throughout experiments. Also, the proposed method in this paper is proved to be more robust under different SNR and/or embedding dimension via explicit formulae and simulations.

  7. Application of Wavelet Denoising Algorithm in Noisy Blind Source Separation%小波去噪算法在含噪盲源分离中的应用

    Institute of Scientific and Technical Information of China (English)

    吴微; 彭华; 王彬

    2015-01-01

    Blind source separation (BSS) algorithms based on the noise‐free model are not applicable when the SNR is low .To deal with this issue ,one way is to denoise the mixtures corrupted by white Gaussian noise ,firstly ,and then utilize the BSS algorithms .Therefore ,a Waveshrink algorithm is proposed based on translation invariant to denoise mixtures with strong noise .The high‐frequency coefficients sliding window method is utilized to estimate the noise variance accurately ,and BayesShrink algorithm is utilized for a more reasonable threshold .Consequently ,the scope of the translation invariant is narrowed without degrading the performance of denoising ,thus reducing the computation amount .Simulation results indi‐cate that the proposed approach perform better in denoising compared with the traditional Waveshrink al‐gorithm ,and can remarkably enhance the separation performance of BSS algorithms ,especially in the case with low signal SNRs .%无噪模型下的盲源分离算法在信噪比较低的情况下并不适用。针对该情况一种解决方案就是先对含有高斯白噪声的混合信号进行去噪预处理,然后使用盲源分离算法进行分离。为此,本文提出了一种适用于信噪比较低条件下的基于平移不变量的小波去噪算法。该算法首先使用高频系数滑动窗口法准确估计含噪混合信号的噪声方差,然后使用Bayesshrink阈值估计算法得到更加合理的阈值,最后在不降低去噪效果的同时缩小了平移不变量的范围,减少了运算量。实验仿真表明,在信噪比较低的情况下,与传统小波去噪算法相比,该算法可以更加有效地去除噪声,在很大程度上提升盲源分离算法的性能。

  8. Dynamic Blind Separation of Mechanical Fault Sources Based on Canonical Variate Analysis and Independent Component Analysis%基于CVA-ICA的机械故障源动态盲分离方法

    Institute of Scientific and Technical Information of China (English)

    李志农; 张芬; 肖尧先

    2015-01-01

    动态盲源分离问题是多故障源盲分离的一个热点。传统的机械故障源分离方法要求满足统计特征保持稳定,且混合系统保持不变等假设,而忽略了时序信息。针对此不足,结合规范变量分析(Canonical variate analysis, CVA)和独立分量分析(Independent component analysis, ICA),提出一种基于CVA-ICA的机械多故障源动态盲分离方法。该方法的基本思想是将源信号看成状态空间的状态变量,观测信号看成状态空间的输出变量,从而将动态混合盲源分离问题转化为状态空间盲源分离问题,利用规范变量分析作为降维工具来构造状态空间,再利用传统的 ICA 算法对规范的观测信号进行盲源分离。仿真研究表明,在处理动态混合的盲分离中,提出的方法明显优于静态 ICA 方法,取得了满意的分离效果。将该方法应用到滚动轴承内圈和滚动体的故障盲分离中,试验结果进一步验证了该方法的有效性。%Dynamic blind source separation is a focus in the blind source separation of multi-fault. Traditional blind source separation (BSS) is restricted to the stable statistical characteristics and static mixture system, and ignores the sequential information. Based on this deficiency, combining to canonical variate analysis (CVA) and independent component analysis (ICA), a dynamic blind source separation method based on CVA-ICA is proposed. In the proposed method, the source signal is regarded as state variable in the state space, observation signal as output variable, thus the dynamics ICA is transform into the state space ICA. The proposed method employs CVA as a reduction tool to construct a state space, then the statistically independent sources are separated by the conventional ICA algorithm. The simulation results show that the CVA-ICA method is superior to traditional blind source separation in the dynamic blind source separation, and has satisfactory

  9. Informed source separation: source coding meets source separation

    OpenAIRE

    Ozerov, Alexey; Liutkus, Antoine; Badeau, Roland; Richard, Gaël

    2011-01-01

    We consider the informed source separation (ISS) problem where, given the sources and the mixtures, any kind of side-information can be computed during a so-called encoding stage. This side-information is then used to assist source separation, given the mixtures only, at the so-called decoding stage. State of the art ISS approaches do not really consider ISS as a coding problem and rely on some purely source separation-inspired strategies, leading to performances that can at best reach those ...

  10. Probabilistic blind deconvolution of non-stationary sources

    DEFF Research Database (Denmark)

    Olsson, Rasmus Kongsgaard; Hansen, Lars Kai

    2004-01-01

    We solve a class of blind signal separation problems using a constrained linear Gaussian model. The observed signal is modelled by a convolutive mixture of colored noise signals with additive white noise. We derive a time-domain EM algorithm `KaBSS' which estimates the source signals...

  11. 基于行列式和稀疏性约束的NMF的欠定盲分离方法%Algorithm for underdetermined blind source separation based on DSNMF

    Institute of Scientific and Technical Information of China (English)

    卢宏; 赵知劲; 杨小牛

    2011-01-01

    The decomposed left matrix of Non-negative Matrix Factorization (NMF) is required to be full column rank,which limits of its application to Underdetermined Blind Source Separation (UBSS). To address this issue, an algorithm for UBSS based on determinant and sparsity constraint of NMF, named DSNMF, was proposed in this paper. On the basis of standard NMF, determinant criterion was used for constraining the left matrix of NMF, while sparsity was used for constraining the right one. In this way, the reconstruction error, the uniqueness of mixing matrix and the spasity of original sources can be equipoised, which leads to the underdetermined blind separation of mixing matrix and original sources. The simulation results show that DSNMF both works well for good and poor sparsity of sources separation.%非负矩阵分解(NMF)要求分解得到的左矩阵为列满秩,这限制了它在欠定盲分离(UBSS)中的应用.针对此问题,提出基于带行列式和稀疏性约束的NMF的欠定盲分离算法--DSNMF.该算法在基本NMF的基础上,对NMF得到的左矩阵进行行列式准则约束,对右矩阵进行稀疏性约束.平衡了重构误差、混合矩阵的唯一性以及分离信号的稀疏特性,实现了对混合矩阵和源信号的欠定盲分离.仿真结果表明,在源信号稀疏性较好和较差两种情况下,DSNMF都能取得良好的分离效果.

  12. A SELF-ADAPTIVE ALGORITHM FOR SINGLE INPUT MULTIPLE OUT BLIND SOURCE SEPARATION%一种自适应单入多出盲源分离方法

    Institute of Scientific and Technical Information of China (English)

    黄书华; 卓东风; 郭一娜

    2013-01-01

    Single input multiple out blind source separation (SIM0_BSS) is a special kind of underdetermined blind source separation.In the process of existing algorithms,too much personal experience is required in judging,and the self-adaptability is poor.To address this problem,we propose that first the ensemble empirical mode decomposition (EEMD) is used to decompose the single-channel signal which is the mixture of multi-channel signals into multi-channel intrinsic mode functions (IMSs) ; then,the principal component analysis is applied to reduce the dimensionality of multi-channel IMFs adaptively,meanwhile the independent component analysis is used to restore the mutualindependent multiple source signals.Finally,the simulation is conducted on periodic mixed signal and biological mixed signal,the simulation results indicate that the proposed algorithm has quick speed with good separation effect than the EEMD_ICA algorithm under different NSR conditions.%单入多出盲源分离SIMO_BSS(Single input multiple out blind source separation)是一种特殊的欠定盲源分离情况.目前算法过程中过多地需要根据个人经验判断,自适应差.针对此问题提出通过经验模态分解EEMD(Ensemble empirical mode decomposition)将由多路信号混合成的单路信号分解为多路本征模态函数IMFs(Intrinsic mode functions),采用主成分分析PCA(Principle cornponent analysis)对多路本征模态函数自适应降维,并利用独立成分分析ICA(Independent component analysis)恢复出相互独立的多路源信号.最后,分别对周期混合信号、生物混合信号进行仿真,仿真结果表明在不同NSR条件下,与EEMD_ICA算法相比,速度快且分离效果较好.

  13. 基于小波半软阈值消噪的盲源分离方法%Blind Source Separation Based on Wavelet Semi-soft Threshold Denoising

    Institute of Scientific and Technical Information of China (English)

    孟宗; 马钊; 刘东; 李晶

    2016-01-01

    为了有效提取含噪机械故障信号中的故障特征信息,研究了一种基于小波半软阈值消噪的盲源分离方法。利用小波半软阈值对故障信号进行消噪处理;采用联合近似对角化算法对信号进行盲源分离;考虑在噪声干扰下预消噪常常不足以消除全部噪声,因此在盲源分离后再进行适当的消噪处理,以提高其分离性能。实验验证了所提出方法的有效性和可行性。%In order to extract fault feature informations from the mechanical malfunction signals with noise,a method of blind source separation was proposed based on wavelet semi-soft threshold de-noising.First,wavelet semi-soft threshold was used to filter the failure signals.Then,joint approxi-mate diagonalization was used as blind source separation method to separate signals.Pretreatment was often not enough to eliminate all noises,therefore,it was necessary to denoise again to improve the separation performance.Finally,the feasibility and validity of this method was verified by experi-ments.

  14. Blind image separation based on exponentiated transmuted Weibull distribution

    OpenAIRE

    Adam, A. M.; Farouk, R. M.; El-aziz, M. E. Abd

    2016-01-01

    In recent years the processing of blind image separation has been investigated. As a result, a number of feature extraction algorithms for direct application of such image structures have been developed. For example, separation of mixed fingerprints found in any crime scene, in which a mixture of two or more fingerprints may be obtained, for identification, we have to separate them. In this paper, we have proposed a new technique for separating a multiple mixed images based on exponentiated t...

  15. Research and Simulation of FECG Signal Blind Separation Algorithm Based on Gradient Method

    Directory of Open Access Journals (Sweden)

    Yu Chen

    2012-08-01

    Full Text Available Independent Component Analysis (ICA is a new developed signal separation and digital analysis technology in recent years. ICA has widely used because it does not need to know the signal prior information, which has became the hot spot in signal processing field research. In this study, we firstly introduce the principle, meaning and blind source separation algorithm based on the gradient. By using the traditional natural gradient algorithm and Equi-variant Adaptive Source Separation via Independent (EASI blind separation algorithm, mixing ECG signals with noises had been separated effectively into the Maternal Electrocardiograph (MECG signal, Fetal Electrocardiograph (FECG signal and noise signal. The algorithm separation test showed that EASI algorithm can better separate the fetal ECG signal and because the gradient algorithm is a kind of online algorithm, which can be used for clinical fetal ECG signal of the real-time detection with important practical value and research significance.

  16. 基于VbMoICA的机械故障盲源分离研究%Blind separation of mechanical fault sources based on variational Bayesian mixture of independent component analysers

    Institute of Scientific and Technical Information of China (English)

    岳秀廷; 李志农; 陈金刚

    2012-01-01

    用独立分量分析(ICA)分解和表示数据时,假设整个数据分布完全可以用一个坐标系来描述.然而,当观测数据是由许多自相似的、非高斯的流形组成时,则硬是用一个单独的、全局的表示是不合适的,这样会产生一个次优的表示.针对ICA在盲源分离中的不足,在变分贝叶斯理论的基础上提出了一种基于变分贝叶斯混合独立分量分析的机械故障源盲分离方法.该方法是考虑到源信号来自于多个坐标系,然后在多个坐标系下建立独立分量分析混合模型对观测信号进行学习分离.实验结果表明,本文提出的方法是非常有效的.%Decomposing and representing data using independent component analysers(ICA)assumes that the whole data distribution is adequately described by one coordinate frame.However,if the observed data consists of various self-similar,non-Gaussian manifolds, enforcing a single, global representation is not appropriate and will produce a sub-optimal representation.In order to make up the lack of independent component analyser in blind sources separations, blind separation of mechanical fault sources based on variational Bayesian mixture of independent component analysers is presented based on variational Bayesian theory in this paper.Conside.ring the source signals coming from multiple frames, the method creats a mixture model of independent component analysers in multiple frameworks for learning the observed signals and separating thenuThe experimental results show that the method proposed in this paper is very effective.

  17. Single channel blind source separation for underwater acoustic signal under multipath condition%多途环境下的单通道水声信号盲源分离

    Institute of Scientific and Technical Information of China (English)

    刘佳; 杨士莪; 朴胜春

    2012-01-01

    A method of single channel blind source separation for underwater acoustic signal was proposed under condition of multipath transmission. Firstly, the multipath time delay was estimated with autocorrelation. Then, the successive multipath signals were added in phase, so as to increase the signal-noise ratio. At last, virtual channels were constructed with the observed data using resample method, the limitation of single channel was overcomed. The simulation results showed that the ship-radiated noise can be separated from ambient noise using this method with single observing channel under condition of multipath transmission, and the method works stably under different SNRs.%提出一种适用于多途环境下的单观测通道水声信号盲源分离方法.该方法首先利用自相关估计多途时延,使经各途径到达的多途信号同相叠加,信号能量得到增强,而噪声由于随机性能量不会增加,进而提高信噪比.然后采用间隔重采样的方法,虚拟多接收通道,解决单通道的欠定问题.仿真分析表明该方法可以有效解决多途环境下的舰船辐射噪声与环境噪声分离,而且在不同信噪比下有较稳定的分离性能.

  18. Real-time adaptive concepts in acoustics blind signal separation and multichannel echo cancellation

    CERN Document Server

    Schobben, Daniel W E

    2001-01-01

    Blind Signal Separation (BSS) deals with recovering (filtered versions of) source signals from an observed mixture thereof. The term `blind' relates to the fact that there are no reference signals for the source signals and also that the mixing system is unknown. This book presents a new method for blind signal separation, which is developed to work on microphone signals. Acoustic Echo Cancellation (AEC) is a well-known technique to suppress the echo that a microphone picks up from a loudspeaker in the same room. Such acoustic feedback occurs for example in hands-free telephony and can lead to a perceived loud tone. For an application such as a voice-controlled television, a stereo AEC is required to suppress the contribution of the stereo loudspeaker setup. A generalized AEC is presented that is suited for multi-channel operation. New algorithms for Blind Signal Separation and multi-channel Acoustic Echo Cancellation are presented. A background is given in array signal processing methods, adaptive filter the...

  19. 基于广义相关系数的后非线性盲信号分离算法%Blind source separation algorithm for post-nonlinear mixture based on generalized correlation coefficient

    Institute of Scientific and Technical Information of China (English)

    张贤彪; 黄高明; 刘德志; 陶涛

    2012-01-01

    According to the problem that the independence criterion based on the minimization of mutual information is not normalized, a blind source separation(BSS) algorithm for post-nonlinear mixture(PNL) based on general correlation coefficient is introduced in this paper. Firstly, the PNL is taken as an indraft point to summarize this algorithm, which is the more practicable approximation to realism rather than linear model, meanwhile the independence criterion based on the generalized correlation coefficient is discussed. Then score function based on a Gram-Charlier expansion of densities is proposed. Finally, combined with the steepest descent method, the computations of regular matrix and parametric nonlinear mapping are given. The simulation results show that the proposed method is effective in BSS for the PNL and for the quantitative analysis of nonlinear correlation between variables.%基于互信息最小化的独立性测度对各分离信号间的非线性相关度度量没有归一化的问题,提出一种基于广义相关系数的肓信号分离(BSS)算法.首先选取后非线性混叠模型(PNL)分析基于广义相关系数的独立性测度;然后采用Gram-Charlier扩展形式估计输出参数并获取评价几率函数,结合最陡下降法求得分离矩阵和参数化可逆非线性映射的算法迭代公式.仿真结果表明,采用所提出的算法能够定量分析各分离信号间的非线性相关程度,有效分离后非线性混叠信号.

  20. 欠定盲分离方法预报水下双层圆柱壳辐射声场%Prediction of radiated acoustic field for double cylindrical shell under water using underdetermined blind source separation

    Institute of Scientific and Technical Information of China (English)

    陶襄樊; 陈美霞; 魏建辉

    2012-01-01

    水下双层加筋圆柱壳振动和辐射声场的预估对其噪声控制具有重要意义.以此为出发点,基于双层加筋圆柱壳干模态叠加原理,运用欠定盲分离方法,实现了有限数目测点预报结构振动和辐射声场的目的,并用数值方法对预报结果的有效性进行了验证.结果表明,欠定盲分离方法可以对水下双层加筋圆柱壳辐射声场进行预报,并且该预报方法对测点的位置、选取的模态阶数没有严格的要求,所需要的测点数目也较少,有很好的适用性.%The prediction of vibration and radiated acoustic field for double ring-stiffened cylindrical shell under water is of great importance to noise control. Based on the theory of modal superposition of double ring-stiffened cylindrical shell in vacuum, this paper proposes an underdetermined blind source separation method which achieves the aim of predicting the vibration and radiated acoustic field of the double ring-stiffened cylindrical shell under water with a few measuring points. The validity of the prediction results is analyzed through numerical method. It demonstrates that the prediction is reliable. And it does not has rigorous requirements on the location of the measuring points and the number of selected modes, otherwise, the number of the measuring points needed is acceptable, consequently, this method has much better applicability.

  1. A TIME-FREQUENCY BLIND SEPARATION METHOD FOR UNDERDETERMINED SPEECH MIXTURES

    Institute of Scientific and Technical Information of China (English)

    Lv Yao; Li Shuangtian

    2008-01-01

    The proposed Blind Source Separation method (BSS),based on sparse representations,fuses time-frequency analysis and the clustering approach to separate underdetermined speech mixtures in the anechoic case regardless of the number of sources. The method remedies the insufficiency of the Degenerate Unmixing Estimation Technique (DUET) which assumes the number of sources a priori. In the proposed algorithm,the Short-Time Fourier Transform (STFT) is used to obtain the sparse rep-resentations,a clustering method called Unsupervised Robust C-Prototypes (URCP) which can accurately identify multiple clusters regardless of the number of them is adopted to replace the histo-gram-based technique in DUET,and the binary time-frequency masks are constructed to separate the mixtures. Experimental results indicate that the proposed method results in a substantial increase in the average Signal-to-Interference Ratio (SIR),and maintains good speech quality in the separation results.

  2. The Application of FastICA Combined with Related Function in Blind Signal Separation

    OpenAIRE

    Dengao Li; Junmin Zhao; Hongyan Liu; Defeng Hao

    2014-01-01

    Blind source separation (BSS) has applications in the fields of data compression, feature recognition, speech, audio, and biosignal processing. Identification of ECG signal is one of the challenges in the biosignal processing. Proposed in this paper is a new method, which is the combination of related function relevance to estimated signal and negative entropy in fast independent component analysis (FastICA) as objective function, and the iterative formula is derived without any assumptions; ...

  3. Bayesian Source Separation and Localization

    CERN Document Server

    Knuth, K H

    1998-01-01

    The problem of mixed signals occurs in many different contexts; one of the most familiar being acoustics. The forward problem in acoustics consists of finding the sound pressure levels at various detectors resulting from sound signals emanating from the active acoustic sources. The inverse problem consists of using the sound recorded by the detectors to separate the signals and recover the original source waveforms. In general, the inverse problem is unsolvable without additional information. This general problem is called source separation, and several techniques have been developed that utilize maximum entropy, minimum mutual information, and maximum likelihood. In previous work, it has been demonstrated that these techniques can be recast in a Bayesian framework. This paper demonstrates the power of the Bayesian approach, which provides a natural means for incorporating prior information into a source model. An algorithm is developed that utilizes information regarding both the statistics of the amplitudes...

  4. Blind Separation by Redundancy Reduction in a Recurrent Neural Network

    Institute of Scientific and Technical Information of China (English)

    LIU Ju; NIE Kaibao; HE Zhenya

    2001-01-01

    In this paper, a novel information the-ory criterion is proposed for blind source separationbased on a fully recurrent neural network, and a learn-ing algorithm is then developed. Stochastic naturalgradient descent algorithm is used in this algorithm.The proposed algorithm can ensure the maximizationof transferred information when a Hebb term is intro-duced to express the derivative of information missing.At the same time, the mutual information of outputs isminimized so as to make the outputs mutually statis-tically independent. The computer simulation showsthe validity and the good performance of the proposedalgorithm.

  5. 基于盲源分离的稀疏植被区土壤含盐量反演%Estimation of Soil Salt Content over Partially Vegetated Areas Based on Blind Source Separation

    Institute of Scientific and Technical Information of China (English)

    刘娅; 潘贤章; 石荣杰; 李燕丽; 王昌昆; 李志婷

    2016-01-01

    植被对土壤光谱的干扰是目前土壤盐渍化遥感监测的重要限制因素之一,探索消除稀疏植被覆盖区植被对光谱影响的方法,对提高土壤含盐量遥感反演精度具有重要意义。本文通过对189组不同植被覆盖度且不同盐渍化程度种植微区野外实测地表可见-近红外反射光谱进行分析,比较并评价了基于原始光谱和盲源分离(blind source separation,BSS)后光谱预测土壤含盐量的结果。结果表明:地表植被覆盖严重影响基于可见-近红外反射光谱的土壤含盐量反演精度。盲源分离方法,尤其是基于方程z=tanh(y)的独立分量分析(independent components analysis,ICA)算法,可有效分解植被和土壤的混合光谱,并提高植被覆盖下基于可见-近红外反射光谱的土壤含盐量反演精度。该方法为植被覆盖区大尺度土壤盐渍化遥感监测提供了方法指导。%The technology of image spectroscopy has been widely used in soil attribute mapping in the past few decades. However,vegetation cover seriously affects the acquisition of soil spectral information, leading to misestimating of soil attributes by visible and near-infrared(vis-NIR)spectroscopy. The traditional solution dealt with vegetation cover interfering soil spectra by masking out the areas with high vegetation coverage,thus resulting in absence of soil information for these areas. Some researchers also tried to use vegetation indices to estimate soil attributes,with results showing that the general applicability and transferability of these vegetation indices was limited by study areas and crop varieties. Therefore,how to remove the influence of vegetation on soil spectrum has become a crucial issue in estimating soil components, such as salt content over partially vegetated surfaces. The residual spectral unmixing method was previously used to separate different components of a mixed spectrum,however,the percentage of

  6. Blind speech separation based on undecimated wavelet packet-perceptual filterbanks and independent component analysis

    Directory of Open Access Journals (Sweden)

    Ibrahim Missaoui

    2011-05-01

    Full Text Available In this paper, we address the problem of blind separation of speech mixtures. We propose a new blind speech separation system, which integrates a perceptual filterbank and independent component analysis (ICA and using kurtosis criterion. The perceptual filterbank was designed by adjusting undecimated wavelet packet decomposition (UWPD tree in order to accord to critical band characteristics of psycho-acoustic model. Our proposed technique consists on transforming the observations signals into an adequate representation using UWPD and Kurtosis maximization criterion in a new preprocessing step in order to increase the non-Gaussianity which is a pre-requirement for ICA. Experiments were carried out with the instantaneous mixture of two speech sources using two sensors. The obtained results show that the proposed method gives a considerable improvement when compared with FastICA and other techniques.

  7. Blind Component Separation in Wavelet Space: Application to CMB Analysis

    OpenAIRE

    2005-01-01

    It is a recurrent issue in astronomical data analysis that observations are unevenly sampled or incomplete maps with missing patches or intentionaly masked parts. In addition, many astrophysical emissions are non stationary processes over the sky. Hence spectral estimation using standard Fourier transforms is no longer reliable. Spectral matching ICA (SMICA) is a source separation method based on covariance matching in Fourier space which is successfully used for the separation of diffuse ast...

  8. Blind component separation in wavelet space. Application to CMB analysis

    OpenAIRE

    Delabrouille, J.; J. -L. Starck; J.-F. Cardoso; Moudden, Y.

    2004-01-01

    It is a recurrent issue in astronomical data analysis that observations are unevenly sampled or incomplete maps with missing patches or intentionaly masked parts. In addition, many astrophysical emissions are non stationary processes over the sky. Hence spectral estimation using standard Fourier transforms is no longer reliable. Spectral matching ICA (SMICA) is a source separation method based on covariance matching in Fourier space which is successfully used for the separation of diffuse ast...

  9. Blind signal separation of underdetermined mixtures based on clustering algorithms on planes

    Institute of Scientific and Technical Information of China (English)

    Xie Shengli; Tan Beihai; Fu Yuli

    2007-01-01

    Based on clustering method on planes, blind signal separation (BSS) of underdetermined mixtures with three observed signals is discussed. The condition of sufficient sparsity of the source signals is not necessary when clustering method on planes is used. In other words, it needs not that only one source signal plays the main role among others at one time. The proposed method uses normal line clustering of planes first. Then, the mixing matrix can be identified via deciding the intersection lines of the planes. This method is an effective implement of the new theory presented by Georgiev. Simulations illustrate accuracy and restoring capability of the method to estimate the mixing matrix.

  10. Nonnegative matrix factorization: a blind spectra separation method for in vivo fluorescent optical imaging.

    Science.gov (United States)

    Montcuquet, Anne-Sophie; Hervé, Lionel; Navarro, Fabrice; Dinten, Jean-Marc; Mars, Jérôme I

    2010-01-01

    Fluorescence imaging in diffusive media is an emerging imaging modality for medical applications that uses injected fluorescent markers that bind to specific targets, e.g., carcinoma. The region of interest is illuminated with near-IR light and the emitted back fluorescence is analyzed to localize the fluorescence sources. To investigate a thick medium, as the fluorescence signal decreases with the light travel distance, any disturbing signal, such as biological tissues intrinsic fluorescence (called autofluorescence) is a limiting factor. Several specific markers may also be simultaneously injected to bind to different molecules, and one may want to isolate each specific fluorescent signal from the others. To remove the unwanted fluorescence contributions or separate different specific markers, a spectroscopic approach is explored. The nonnegative matrix factorization (NMF) is the blind positive source separation method we chose. We run an original regularized NMF algorithm we developed on experimental data, and successfully obtain separated in vivo fluorescence spectra.

  11. Jammer Suppression in DS-CDMA Communications using Parafac-based Blind Separation

    Directory of Open Access Journals (Sweden)

    Xu Lingyun

    2016-01-01

    Full Text Available In this paper we propose to apply parafac-based source separation techniques for jammer suppression in direct spread spectrum communication systems. The jammer excision is formulated as an optimization problem and a new algorithm is presented which is based on the parafac tri-iterative least square algorithm. By jointly diagonalizing the time delay correlation matrix of the observed signals and using the new proposed method, a better solution is achieved. The proposed algorithm can successfully separate communication signals and jamming signals. Simulation results reveal that our proposed algorithm has the better blind signal separation performance than joint diagonalization method. Our proposed algorithm doesn’t require whitening processing. Moreover our proposed algorithm works well in the underdetermined condition, where the number of sources exceeds than the number of antennas.

  12. Complex-wave retrieval based on blind signal separation

    Institute of Scientific and Technical Information of China (English)

    Xiaodong Chai; Chengpeng Zhou; Zhaoyan Feng; Yinhua Wang; Yansheng Zuo

    2006-01-01

    In the process of the reconstruction of digital holography, the traditional methods of diffraction and filtration are commonly adopted to recover the original complex-wave signal. Influenced by twin-image and zero-order terms, the above-mentioned methods, however, either limit the field of vision or result in the loss of the amplitude and phase. A new method for complex-wave retrieval is presented, which is based on blind signal separation. Three frames of holograms are captured by a charge coupled device (CCD)camera to form an observation signal. The term containing only amplitude and phase of complex-wave is separated, by means of independent component analysis, from the observation signal, which effectively eliminates the zero-order term. Finally, the complex-wave retrieval of pure phase wavefront is achieved.Experimental results show that this method can better recover the amplitude and phase of the original complex-wave even when there is a frequency spectrum mixture in the hologram.

  13. Blind Separation of Two Users Based on User Delays and Optimal Pulse-Shape Design

    Directory of Open Access Journals (Sweden)

    Poor HVincent

    2010-01-01

    Full Text Available A wireless network is considered, in which two spatially distributed users transmit narrow-band signals simultaneously over the same channel using the same power. User separation is achieved by oversampling the received signal and formulating a virtual multiple-input multiple-output (MIMO system based on the resulting polyphase components. Because of oversampling, high correlations can occur between the columns of the virtual MIMO system matrix which can be detrimental to user separation. A novel pulse-shape waveform design is proposed that results in low correlation between the columns of the system matrix, while it exploits all available bandwidth as dictated by a spectral mask. It is also shown that the use of successive interference cancelation in combination with blind source separation further improves the separation performance.

  14. Improved Method of Blind Speech Separation with Low Computational Complexity

    Directory of Open Access Journals (Sweden)

    Kazunobu Kondo

    2011-01-01

    a frame-wise spectral soft mask method based on an interchannel power ratio of tentative separated signals in the frequency domain. The soft mask cancels the transfer function between sources and separated signals. A theoretical analysis of selection criteria and the soft mask is given. Performance and effectiveness are evaluated via source separation simulations and a computational estimate, and experimental results show the significantly improved performance of the proposed method. The segmental signal-to-noise ratio achieves 7 [dB] and 3 [dB], and the cepstral distortion achieves 1 [dB] and 2.5 [dB], in anechoic and reverberant conditions, respectively. Moreover, computational complexity is reduced by more than 80% compared with unmodified FDICA.

  15. Blind Component Separation in Wavelet Space: Application to CMB Analysis

    Directory of Open Access Journals (Sweden)

    J. Delabrouille

    2005-09-01

    Full Text Available It is a recurrent issue in astronomical data analysis that observations are incomplete maps with missing patches or intentionally masked parts. In addition, many astrophysical emissions are nonstationary processes over the sky. All these effects impair data processing techniques which work in the Fourier domain. Spectral matching ICA (SMICA is a source separation method based on spectral matching in Fourier space designed for the separation of diffuse astrophysical emissions in cosmic microwave background observations. This paper proposes an extension of SMICA to the wavelet domain and demonstrates the effectiveness of wavelet-based statistics for dealing with gaps in the data.

  16. Blindness

    Science.gov (United States)

    ... Got Homework? Here's Help White House Lunch Recipes Blindness KidsHealth > For Kids > Blindness Print A A A ... help, are sometimes called "legally blind." What Causes Blindness? Vision problems can develop before a baby is ...

  17. Atrial fibrillatory signal estimation using blind source extraction algorithm based on high-order statistics

    Institute of Scientific and Technical Information of China (English)

    WANG Gang; RAO NiNi; ZHANG Ying

    2008-01-01

    The analysis and the characterization of atrial fibrillation (AF) requires,in a previous key step,the extraction of the atrial activity (AA) free from 12-lead electrocardiogram (ECG).This contribution proposes a novel non-invasive approach for the AA estimation in AF episodes.The method is based on blind source extraction (BSE) using high order statistics (HOS).The validity and performance of this algorithm are confirmed by extensive computer simulations and experiments on realworld data.In contrast to blind source separation (BSS) methods,BSE only extract one desired signal,and it is easy for the machine to judge whether the extracted signal is AA source by calculating its spectrum concentration,while it is hard for the machine using BSS method to judge which one of the separated twelve signals is AA source.Therefore,the proposed method is expected to have great potential in clinical monitoring.

  18. Blind Separation of Acoustic Signals Combining SIMO-Model-Based Independent Component Analysis and Binary Masking

    Directory of Open Access Journals (Sweden)

    Hiekata Takashi

    2006-01-01

    Full Text Available A new two-stage blind source separation (BSS method for convolutive mixtures of speech is proposed, in which a single-input multiple-output (SIMO-model-based independent component analysis (ICA and a new SIMO-model-based binary masking are combined. SIMO-model-based ICA enables us to separate the mixed signals, not into monaural source signals but into SIMO-model-based signals from independent sources in their original form at the microphones. Thus, the separated signals of SIMO-model-based ICA can maintain the spatial qualities of each sound source. Owing to this attractive property, our novel SIMO-model-based binary masking can be applied to efficiently remove the residual interference components after SIMO-model-based ICA. The experimental results reveal that the separation performance can be considerably improved by the proposed method compared with that achieved by conventional BSS methods. In addition, the real-time implementation of the proposed BSS is illustrated.

  19. Blind component separation in wavelet space. Application to CMB analysis

    CERN Document Server

    Moudden, Y; Starck, J L; Delabrouille, J

    2004-01-01

    It is a recurrent issue in astronomical data analysis that observations are unevenly sampled or incomplete maps with missing patches or intentionaly masked parts. In addition, many astrophysical emissions are non stationary processes over the sky. Hence spectral estimation using standard Fourier transforms is no longer reliable. Spectral matching ICA (SMICA) is a source separation method based on covariance matching in Fourier space which is successfully used for the separation of diffuse astrophysical emissions in Cosmic Microwave Background observations. We show here that wavelets, which are standard tools in processing non stationary data, can profitably be used to extend SMICA. Among possible applications, it is shown that gaps in data are dealt with more conveniently and with better results using this extension, wSMICA, in place of the original SMICA. The performances of these two methods are compared on simulated CMB data sets, demonstrating the advantageous use of wavelets.

  20. Research on Seismic Data Noise Reduction in Metallic Ore Based on Wavelet Domain Blind Source Separation JADE Algorithm%金属矿地震数据降噪研究——基于小波域盲分离JADE算法

    Institute of Scientific and Technical Information of China (English)

    王权锋; 胥德平; 詹泽东; 吴海洋

    2012-01-01

    This paper explores the method of seismic exploration data noise reduction in deep metal, and proposes wavelet domain blind separation algorithm processing procedure. The actual noise reduction process and research of the low signal-to-noise ratio (SNR) in a metal mine of Yunnan Province shows that the effect would be better than JADE blind source separation algorithm noise reduction in pure time domain when the seismic data are transformed into wavelet domain blind source separation algorithm of JADE noise reduction processing, and then the wavelet domain is transformed into time domain; and in the de-noising processing, parameter combination must be tested many times according to different parts of the seismic data so as to achieve the best effect of de-noise. It is of practical value and instruction for prospecting blind ores and deep concealed ore deposits in large areas by seismic techniques to combine blind signal theory with wavelet transformation for deep seismic exploration data noise reduction.%探索深部金属矿地震勘查中数据降噪方法,提出小波域盲分离算法处理流程,通过对我国云南地区某金属矿低信噪比资料,进行实际降噪处理研究,结果表明:①将地震数据变换到小波域的盲分离JADE算法降噪处理后,再从小波域变换到时间域,比单纯的时间域内盲分离JADE算法降噪效果要好;②在降噪处理过程中,必须根据不同地区的地震数据多次试验参数组合,以其达到最佳降噪效果.将盲信号理论与小波变换有机结合进行深部金属矿地震勘查数据降噪,对利用地震方法大面积地寻找盲矿和深部隐伏矿有一定的实用价值和指导意义.

  1. Separating More Sources Than Sensors Using Time-Frequency Distributions

    Directory of Open Access Journals (Sweden)

    Belouchrani Adel

    2005-01-01

    Full Text Available We examine the problem of blind separation of nonstationary sources in the underdetermined case, where there are more sources than sensors. Since time-frequency (TF signal processing provides effective tools for dealing with nonstationary signals, we propose a new separation method that is based on time-frequency distributions (TFDs. The underlying assumption is that the original sources are disjoint in the time-frequency (TF domain. The successful method recovers the sources by performing the following four main procedures. First, the spatial time-frequency distribution (STFD matrices are computed from the observed mixtures. Next, the auto-source TF points are separated from cross-source TF points thanks to the special structure of these mixture STFD matrices. Then, the vectors that correspond to the selected auto-source points are clustered into different classes according to the spatial directions which differ among different sources; each class, now containing the auto-source points of only one source, gives an estimation of the TFD of this source. Finally, the source waveforms are recovered from their TFD estimates using TF synthesis. Simulated experiments indicate the success of the proposed algorithm in different scenarios. We also contribute with two other modified versions of the algorithm to better deal with auto-source point selection.

  2. The Application of FastICA Combined with Related Function in Blind Signal Separation

    Directory of Open Access Journals (Sweden)

    Dengao Li

    2014-01-01

    Full Text Available Blind source separation (BSS has applications in the fields of data compression, feature recognition, speech, audio, and biosignal processing. Identification of ECG signal is one of the challenges in the biosignal processing. Proposed in this paper is a new method, which is the combination of related function relevance to estimated signal and negative entropy in fast independent component analysis (FastICA as objective function, and the iterative formula is derived without any assumptions; then the independent components are found by maximizing the objective function. The improved algorithm shorthand for R-FastICA is applied to extract random mixed signals and ventricular late potential (VLP signal from normal ECG signal; simultaneously the performance of R-FastICA algorithm is compared with traditional FastICA through simulation. Experimental results show that R-FastICA algorithm outperforms traditional FastICA with higher similarity coefficient and separation precision.

  3. Searching-and-averaging method of underdetermined blind speech signal separation in time domain

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Underdetermined blind signal separation (BSS) (with fewer observed mixtures than sources) is discussed. A novel searching-and-averaging method in time domain (SAMTD) is proposed. It can solve a kind of problems that are very hard to solve by using sparse representation in frequency domain. Bypassing the disadvantages of traditional clustering (e.g., K-means or potential-function clustering), the durative- sparsity of a speech signal in time domain is used. To recover the mixing matrix, our method deletes those samples, which are not in the same or inverse direction of the basis vectors. To recover the sources, an improved geometric approach to overcomplete ICA (Independent Component Analysis) is presented. Several speech signal experiments demonstrate the good performance of the proposed method.

  4. Blind speech separation based on undecimated wavelet packet-perceptual filterbanks and independent component analysis

    OpenAIRE

    Ibrahim Missaoui; Zied Lachiri

    2011-01-01

    In this paper, we address the problem of blind separation of speech mixtures. We propose a new blind speech separation system, which integrates a perceptual filterbank and independent component analysis (ICA) and using kurtosis criterion. The perceptual filterbank was designed by adjusting undecimated wavelet packet decomposition (UWPD) tree in order to accord to critical band characteristics of psycho-acoustic model. Our proposed technique consists on transforming the observations signals in...

  5. Informed Source Separation: A Bayesian Tutorial

    OpenAIRE

    Knuth, Kevin

    2013-01-01

    Source separation problems are ubiquitous in the physical sciences; any situation where signals are superimposed calls for source separation to estimate the original signals. In this tutorial I will discuss the Bayesian approach to the source separation problem. This approach has a specific advantage in that it requires the designer to explicitly describe the signal model in addition to any other information or assumptions that go into the problem description. This leads naturally to the idea...

  6. How Many Separable Sources? Model Selection In Independent Components Analysis

    DEFF Research Database (Denmark)

    Woods, Roger P.; Hansen, Lars Kai; Strother, Stephen

    2015-01-01

    Unlike mixtures consisting solely of non-Gaussian sources, mixtures including two or more Gaussian components cannot be separated using standard independent components analysis methods that are based on higher order statistics and independent observations. The mixed Independent Components Analysis...... computationally intensive alternative for model selection. Application of the algorithm is illustrated using Fisher’s iris data set and Howells’ craniometric data set. Mixed ICA/PCA is of potential interest in any field of scientific investigation where the authenticity of blindly separated non-Gaussian sources...... might otherwise be questionable. Failure of the Akaike Information Criterion in model selection also has relevance in traditional independent components analysis where all sources are assumed non-Gaussian....

  7. BLIND SPEECH SEPARATION FOR ROBOTS WITH INTELLIGENT HUMAN-MACHINE INTERACTION

    Institute of Scientific and Technical Information of China (English)

    Huang Yulei; Ding Zhizhong; Dai Lirong; Chen Xiaoping

    2012-01-01

    Speech recognition rate will deteriorate greatly in human-machine interaction when the speaker's speech mixes with a bystander's voice.This paper proposes a time-frequency approach for Blind Source Seperation (BSS) for intelligent Human-Machine Interaction(HMI).Main idea of the algorithm is to simultaneously diagonalize the correlation matrix of the pre-whitened signals at different time delays for every frequency bins in time-frequency domain.The prososed method has two merits:(1) fast convergence speed; (2) high signal to interference ratio of the separated signals.Numerical evaluations are used to compare the performance of the proposed algorithm with two other deconvolution algorithms.An efficient algorithm to resolve permutation ambiguity is also proposed in this paper.The algorithm proposed saves more than 10% of computational time with properly selected parameters and achieves good performances for both simulated convolutive mixtures and real room recorded speeches.

  8. A new blind fault component separation algorithm for a single-channel mechanical signal mixture

    Science.gov (United States)

    Wang, Dong; Tse, Peter W.

    2012-10-01

    A vibration signal collected from a complex machine consists of multiple vibration components, which are system responses excited by several sources. This paper reports a new blind component separation (BCS) method for extracting different mechanical fault features. By applying the proposed method, a single-channel mixed signal can be decomposed into two parts: the periodic and transient subsets. The periodic subset is related to the imbalance, misalignment and eccentricity of a machine. The transient subset refers to abnormal impulsive phenomena, such as those caused by localized bearing faults. The proposed method includes two individual strategies to deal with these different characteristics. The first extracts the sub-Gaussian periodic signal by minimizing the kurtosis of the equalized signals. The second detects the super-Gaussian transient signal by minimizing the smoothness index of the equalized signals. Here, the equalized signals are derived by an eigenvector algorithm that is a successful solution to the blind equalization problem. To reduce the computing time needed to select the equalizer length, a simple optimization method is introduced to minimize the kurtosis and smoothness index, respectively. Finally, simulated multiple-fault signals and a real multiple-fault signal collected from an industrial machine are used to validate the proposed method. The results show that the proposed method is able to effectively decompose the multiple-fault vibration mixture into periodic components and random non-stationary transient components. In addition, the equalizer length can be intelligently determined using the proposed method.

  9. Blind Separation of EEG Based on Blind Deconvolution%基于盲反卷积的脑电信号盲分离研究

    Institute of Scientific and Technical Information of China (English)

    黄璐; 王宏

    2016-01-01

    采用卷积混合模型描述观测脑电信号( electroencephalogram,EEG),提出一种基于盲反卷积的EEG盲分离方法。结合EEG源成分的独立性确定代价函数,并采用共轭梯度法进行迭代寻优。针对EEG仿真实验数据进行方法验证,采用分离信号与源信号之间的相关系数作为验证指标。实验结果表明,本文方法可以较好地实现EEG盲分离,为EEG信号处理和其他生理信号处理分析提供理论和方法借鉴。%The convolution mixture model was adopted to describe the as-observed EEG signals, and then a method for the blind separation of EEG based on blind deconvolution was put forward. The cost function was established based on the independence of EEG sources,and iteration was carried out using conjugate gradient method. The verification was implemented with simulation experiment,adopting the correlation coefficients between separated signals and source signals as the verification indexes. Experimental results show that the method proposed can achieve blind separation of EEG successfully,providing a theoretical and practical reference for the processing of EEG and other physiological signals.

  10. Low Complexity Bayesian Single Channel Source Separation

    DEFF Research Database (Denmark)

    Beierholm, Thomas; Pedersen, Brian Dam; Winther, Ole

    2004-01-01

    We propose a simple Bayesian model for performing single channel speech separation using factorized source priors in a sliding window linearly transformed domain. Using a one dimensional mixture of Gaussians to model each band source leads to fast tractable inference for the source signals...... can be estimated quite precisely using ML-II, but the estimation is quite sensitive to the accuracy of the priors as opposed to the source separation quality for known mixing coefficients, which is quite insensitive to the accuracy of the priors. Finally, we discuss how to improve our approach while...

  11. Removal of micropollutants in source separated sanitation

    NARCIS (Netherlands)

    Butkovskyi, A.

    2015-01-01

    Source separated sanitation is an innovative sanitation method designed for minimizing use of energy and clean drinking water, and maximizing reuse of water, organics and nutrients from waste water. This approach is based on separate collection and treatment of toilet wastewater (black water) and th

  12. Audio Source Separation Using a Deep Autoencoder

    OpenAIRE

    Jang, Giljin; Kim, Han-Gyu; Oh, Yung-Hwan

    2014-01-01

    This paper proposes a novel framework for unsupervised audio source separation using a deep autoencoder. The characteristics of unknown source signals mixed in the mixed input is automatically by properly configured autoencoders implemented by a network with many layers, and separated by clustering the coefficient vectors in the code layer. By investigating the weight vectors to the final target, representation layer, the primitive components of the audio signals in the frequency domain are o...

  13. Blind Separation of DS-CDMA Signals with ICA Method

    OpenAIRE

    Miao Yu; Jianzhong Chen; Lei Shen; Shiju Li

    2011-01-01

    The estimation of pseudo noise sequence and information sequence is of great importance in the security of DS-CDMA system, which remains a hot research problem in reconnaissance and supervision of wireless communication. In DS-CDMA system, the pseudo noise sequences of different users are uncorrelated and the information sequences of different users are statistical independent, thus independent component analysis (ICA) could be introduced to separate the DS-CDMA signals with little prior know...

  14. MAXIMUM LIKELIHOOD SOURCE SEPARATION FOR FINITE IMPULSE RESPONSE MULTIPLE INPUT—MULTIPLE OUTPUT CHANNELS IN THE PRESENCE OF ADDITIVE NOISE

    Institute of Scientific and Technical Information of China (English)

    AaziTakpaya; WeiGang

    2003-01-01

    Blind identification-blind equalization for finite Impulse Response(FIR)Multiple Input-Multiple Output(MIMO)channels can be reformulated as the problem of blind sources separation.It has been shown that blind identification via decorrelating sub-channels method could recover the input sources.The Blind Identification via Decorrelating Sub-channels(BIDS)algorithm first constructs a set of decorrelators,which decorrelate the output signals of subchannels,and then estimates the channel matrix using the transfer functions of the decorrelators and finally recovers the input signal using the estimated channel matrix.In this paper,a new qpproximation of the input source for FIR-MIMO channels based on the maximum likelihood source separation method is proposed.The proposed method outperforms BIDS in the presence of additive white Garssian noise.

  15. MAXIMUM LIKELIHOOD SOURCE SEPARATION FOR FINITE IMPULSE RESPONSE MULTIPLE INPUT-MULTIPLE OUTPUT CHANNELS IN THE PRESENCE OF ADDITIVE NOISE

    Institute of Scientific and Technical Information of China (English)

    Kazi Takpaya; Wei Gang

    2003-01-01

    Blind identification-blind equalization for Finite Impulse Response (FIR) Multiple Input-Multiple Output (MIMO) channels can be reformulated as the problem of blind sources separation. It has been shown that blind identification via decorrelating sub-channels method could recover the input sources. The Blind Identification via Decorrelating Sub-channels(BIDS)algorithm first constructs a set of decorrelators, which decorrelate the output signals of subchannels, and then estimates the channel matrix using the transfer functions of the decorrelators and finally recovers the input signal using the estimated channel matrix. In this paper, a new approximation of the input source for FIR-MIMO channels based on the maximum likelihood source separation method is proposed. The proposed method outperforms BIDS in the presence of additive white Gaussian noise.

  16. A source separation approach to enhancing marine mammal vocalizations.

    Science.gov (United States)

    Gur, M Berke; Niezrecki, Christopher

    2009-12-01

    A common problem in passive acoustic based marine mammal monitoring is the contamination of vocalizations by a noise source, such as a surface vessel. The conventional approach in improving the vocalization signal to noise ratio (SNR) is to suppress the unwanted noise sources by beamforming the measurements made using an array. In this paper, an alternative approach to multi-channel underwater signal enhancement is proposed. Specifically, a blind source separation algorithm that extracts the vocalization signal from two-channel noisy measurements is derived and implemented. The proposed algorithm uses a robust decorrelation criterion to separate the vocalization from background noise, and hence is suitable for low SNR measurements. To overcome the convergence limitations resulting from temporally correlated recordings, the supervised affine projection filter update rule is adapted to the unsupervised source separation framework. The proposed method is evaluated using real West Indian manatee (Trichechus manatus latirostris) vocalizations and watercraft emitted noise measurements made within a typical manatee habitat in Florida. The results suggest that the proposed algorithm can improve the detection range of a passive acoustic detector five times on average (for input SNR between -10 and 5 dB) using only two receivers. PMID:20000920

  17. Removal of micropollutants in source separated sanitation

    OpenAIRE

    Butkovskyi, A.

    2015-01-01

    Source separated sanitation is an innovative sanitation method designed for minimizing use of energy and clean drinking water, and maximizing reuse of water, organics and nutrients from waste water. This approach is based on separate collection and treatment of toilet wastewater (black water) and the rest of the domestic wastewater (grey water). Different characteristics of wastewater streams facilitate recovery of energy, nutrients and fresh water. To ensure agricultural or ecological reuse ...

  18. Phase recovery in NMF for audio source separation: an insightful benchmark

    OpenAIRE

    Magron, Paul; Badeau, Roland; David, Bertrand

    2016-01-01

    Nonnegative Matrix Factorization (NMF) is a powerful tool for decomposing mixtures of audio signals in the Time-Frequency (TF) domain. In applications such as source separation, the phase recovery for each extracted component is a major issue since it often leads to audible artifacts. In this paper, we present a methodology for evaluating various NMF-based source separation techniques involving phase reconstruction. For each model considered, a comparison between two approaches (blind separat...

  19. Non-Stationary Brain Source Separation for Multi-Class Motor Imagery

    OpenAIRE

    Gouy-Pailler, Cedric; Congedo, Marco; Brunner, Clemens; Jutten, Christian; Pfurtscheller, Gert

    2010-01-01

    International audience This article describes a method to recover taskrelated brain sources in the context of multi-class Brain- Computer Interfaces (BCIs) based on non-invasive electroencephalography (EEG). We extend the method Joint Approximate Diagonalization (JAD) for spatial filtering using a maximum likelihood framework. This generic formulation (1) bridges the gap between the Common Spatial Patterns (CSP) and Blind Source Separation (BSS) of non-stationary sources, and (2) leads to ...

  20. EEG signals processed by wavelet de-noising and blind source separation%基于小波消噪和盲源分离的脑电信号处理方法

    Institute of Scientific and Technical Information of China (English)

    罗志增; 徐斌

    2011-01-01

    针对脑电信号中噪声及夹杂的眼电、心电等伪迹,采用小波分解重构消噪和基于熵估计的RADICAL算法进行消除.对3路脑电观测信号进行小波消噪和白化处理后,通过雅可比旋转矩阵分别对其中的两两组合信号用RADICAL算法进行分离,得出最优分离矩阵完成盲源分离,并引入互相关系数、矩阵相关系数验证算法的有效性.实验结果表明:源信号未知的3路相互串扰脑电信号盲分离后各个分量之间的互相关系数近似为0,并且其矩阵相关系数每行均有大于0.95的值,优于常用的FastICA算法,说明该方法能有效去除脑电信号中噪声和伪迹.%In order to remove the noise and artifacts(VEOG (vertical ectro-oculogram), EKG (electrocardiogram)) in EEG signals, the wavelet decomposition and reconstruction denoising plus the RADICAL algorithm based on entropy estimates were adopted. After wavelet de-noing and pre-whit-ening, the optimal separation matrix was obtained by using RADICAL algorithm to process the EEG signals combined with Jacobi rotation matrix. Then, the paper introduced cross-correlation coefficient and matrix cross-correlation coefficient to prove the effectiveness of the proposed method. The experimental results indicate that the cross-correlation coefficient of each component for the three mutual crosstalk signals processed by RADICAL algorithm is approximate to 0 and each row of the matrix cross-correlation coefficient have the value larger than 0. 95 which is better than FastICA algorithm. It proves that the proposed method can effectively remove the noise and artifacts in EEG signals.

  1. On the Separability of Ill-Conditioned Convolutive Mixtures of Sources with Small Time Delay%微延迟病态卷积混叠盲源分离的可分性研究

    Institute of Scientific and Technical Information of China (English)

    刘海林; 谢胜利; 章晋龙

    2003-01-01

    The paper researches separability of blind sources of convolutive mixtures on the assumption that the num-ber of sensors is less than that of sources. When time delay is small, the necessary condition of separability of the ill-conditioned convolutive mixtures is given through transforming blind sources of convolutive mixtures into that of lin-ear mixtures.

  2. Blind source identification from the multichannel surface electromyogram

    International Nuclear Information System (INIS)

    The spinal circuitries combine the information flow from the supraspinal centers with the afferent input to generate the neural codes that drive the human skeletal muscles. The muscles transform the neural drive they receive from alpha motor neurons into motor unit action potentials (electrical activity) and force. Thus, the output of the spinal cord circuitries can be examined noninvasively by measuring the electrical activity of skeletal muscles at the surface of the skin i.e. the surface electromyogram (EMG). The recorded multi-muscle EMG activity pattern is generated by mixing processes of neural sources that need to be identified from the recorded signals themselves, with minimal or no a priori information available. Recently, multichannel source separation techniques that rely minimally on a priori knowledge of the mixing process have been developed and successfully applied to surface EMG. They act at different scales of information extraction to identify: (a) the activation signals shared by synergistic skeletal muscles, (b) the specific neural activation of individual muscles, separating it from that of nearby muscles i.e. from crosstalk, and (c) the spike trains of the active motor neurons. This review discusses the assumptions made by these methods, the challenges and limitations, as well as examples of their current applications. (topical review)

  3. Remote diffuse reflectance spectroscopy sensor for tissue engineering monitoring based on blind signal separation.

    Science.gov (United States)

    Martín-Mateos, Pedro; Crespo-Garcia, Sergio; Ruiz-Llata, Marta; Lopez-Fernandez, José Ramón; Jorcano, José Luis; Del Rio, Marcela; Larcher, Fernando; Acedo, Pablo

    2014-09-01

    In this study the first results on evaluation and assessment of grafted bioengineered skin substitutes using an optical Diffuse Reflectance Spectroscopy (DRS) system with a remote optical probe are shown. The proposed system is able to detect early vascularization of skin substitutes expressing the Vascular Endothelial Growth Factor (VEGF) protein compared to normal grafts, even though devitalized skin is used to protect the grafts. Given the particularities of the biological problem, data analysis is performed using two Blind Signal Separation (BSS) methods: Principal Component Analysis (PCA) and Independent Component Analysis (ICA). These preliminary results are the first step towards point-of-care diagnostics for skin implants early assessment. PMID:25401034

  4. Blind, high-resolution, space-time separation of multipaths in an ionospheric propagation

    Science.gov (United States)

    Chenu-Tournier, M.; Larzabal, P.; Barbot, J. P.; Grouffaud, J.; Ferreol, A.

    2000-01-01

    The ionospheric radio electrical transmissions have multiple paths due to the inhomogeneity of the propagation medium, that is, the ionospheric layers. Tactical applications such as radiolocation and radiocommunications systems need blind, high-resolution identification of multipath channels. This work concerns the separation of the ionospheric paths and is based on recent work done on blind deconvolution which can estimate the impulse responses of a propagation channel. In this way, on the basis of a parametric model of the paths, we propose a blind, spatiotemporal identification of the propagation channel. The parameters that characterize the propagation model are the directions of arrivals (DOA) θ, time delays τ, and complex gains α (also called fading). We propose an algorithm that can both estimate the multipath parameters and test them on real life data. This new method needs fewer snapshots than other methods recently proposed, and thus can monitor more quickly varying channels. Moreover, compared to recent work we have relaxed the problem of making successive estimates of the impulse responses. The proposed method can also identify more paths than the number of sensors. An extension of the algorithm will be presented by including polarization diversity and thus increases the resolution. The proposed methods are illustrated on experimental data.

  5. A method for blind separation of components information from mixed pixel

    Institute of Scientific and Technical Information of China (English)

    FAN Wenjie; XU Xiru

    2006-01-01

    In the field of remote sensing, it is important to separate the component information from mixed pixel. If the physical process of remote sensing can be expressed by a set of linear equations, the remote sensing information matrix is equal to the weight matrix multiplied by the component information matrix. Generally speaking, the precondition of retrieval of component information matrix is that the weight matrix is known. However, the blind signal separation (BSS) method can separate the matrix unconditionally, whose basic principle is that the additive information needing separation can be achieved from the statistical characteristics contained in a mass of samples in the remotely sensed information matrix. Therefore, the values of the component information matrix and the weight matrix can be estimated. The wave shape of components can be retrieved by BSS, but the amplitude cannot. In this paper, the plant-soil mixed pixels were chosen as the studying targets in this paper to quantitatively separate the component information and solve the uncertainty of BSS.Simulation and field test verify the reliability of the method. Results show that the BSS can be one of the effective methods of mixed pixel separation, and the foreground of application is very promising.

  6. Separation of Correlated Astrophysical Sources Using Multiple-Lag Data Covariance Matrices

    Directory of Open Access Journals (Sweden)

    Baccigalupi C

    2005-01-01

    Full Text Available This paper proposes a new strategy to separate astrophysical sources that are mutually correlated. This strategy is based on second-order statistics and exploits prior information about the possible structure of the mixing matrix. Unlike ICA blind separation approaches, where the sources are assumed mutually independent and no prior knowledge is assumed about the mixing matrix, our strategy allows the independence assumption to be relaxed and performs the separation of even significantly correlated sources. Besides the mixing matrix, our strategy is also capable to evaluate the source covariance functions at several lags. Moreover, once the mixing parameters have been identified, a simple deconvolution can be used to estimate the probability density functions of the source processes. To benchmark our algorithm, we used a database that simulates the one expected from the instruments that will operate onboard ESA's Planck Surveyor Satellite to measure the CMB anisotropies all over the celestial sphere.

  7. A Modified Infomax ICA Algorithm for fMRI Data Source Separation

    Directory of Open Access Journals (Sweden)

    Amir A. Khaliq

    2013-05-01

    Full Text Available This study presents a modified infomax model of Independent Component Analysis (ICA for the source separation problem of fMRI data. Functional MRI data is processed by different blind source separation techniques including Independent Component Analysis (ICA. ICA is a statistical decomposition method used for multivariate data source separation. ICA algorithm is based on independence of extracted sources for which different techniques are used like kurtosis, negentropy, information maximization etc. The infomax method of ICA extracts unknown sources from a number of mixtures by maximizing the negentropy thus ensuring independence. In this proposed modified infomax model a higher order contrast function is used which results in fast convergence and accuracy. The Proposed algorithm is applied to general simulated signals and simulated fMRI data. Comparison of correlation results of the proposed algorithm with the conventional infomax algorithm shows better performance.

  8. A blind separation method of overlapped multi-components based on time varying AR model

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    A method utilizing single channel recordings to blindly separate the multicomponents overlapped in time and frequency domains is proposed in this paper. Based on the time varying AR model, the instantaneous frequency and amplitude of each signal component are estimated respectively, thus the signal component separation is achieved. By using prolate spheroidal sequence as basis functions to expand the time varying parameters of the AR model, the method turns the problem of linear time varying parameters estimation to a linear time invariant parameter estimation problem, then the parameters are estimated by a recursive algorithm. The computation of this method is simple, and no prior knowledge of the signals is needed. Simulation results demonstrate validity and excellent performance of this method.

  9. Practically Efficient Blind Speech Separation Using Frequency Band Selection Based on Magnitude Squared Coherence and a Small Dodecahedral Microphone Array

    Directory of Open Access Journals (Sweden)

    Kazunobu Kondo

    2012-01-01

    Full Text Available Small agglomerative microphone array systems have been proposed for use with speech communication and recognition systems. Blind source separation methods based on frequency domain independent component analysis have shown significant separation performance, and the microphone arrays are small enough to make them portable. However, the level of computational complexity involved is very high because the conventional signal collection and processing method uses 60 microphones. In this paper, we propose a band selection method based on magnitude squared coherence. Frequency bands are selected based on the spatial and geometric characteristics of the microphone array device which is strongly related to the dodecahedral shape, and the selected bands are nonuniformly spaced. The estimated reduction in the computational complexity is 90% with a 68% reduction in the number of frequency bands. Separation performance achieved during our experimental evaluation was 7.45 (dB (signal-to-noise ratio and 2.30 (dB (cepstral distortion. These results show improvement in performance compared to the use of uniformly spaced frequency band.

  10. Bayesian semi-blind component separation for foreground removal in interferometric 21-cm observations

    CERN Document Server

    Zhang, Le; Karakci, Ata; Korotkov, Andrei; Sutter, P M; Timbie, Peter T; Tucker, Gregory S; Wandelt, Benjamin D

    2016-01-01

    We present in this paper a new Bayesian semi-blind approach for foreground removal in observations of the 21-cm signal with interferometers. The technique, which we call HIEMICA (HI Expectation-Maximization Independent Component Analysis), is an extension of the Independent Component Analysis (ICA) technique developed for two-dimensional (2D) CMB maps to three-dimensional (3D) 21-cm cosmological signals measured by interferometers. This technique provides a fully Bayesian inference of power spectra and maps and separates the foregrounds from signal based on the diversity of their power spectra. Only relying on the statistical independence of the components, this approach can jointly estimate the 3D power spectrum of the 21-cm signal and, the 2D angular power spectrum and the frequency dependence of each foreground component, without any prior assumptions about foregrounds. This approach has been tested extensively by applying it to mock data from interferometric 21-cm intensity mapping observations. Based on ...

  11. Blind Source Parameters for Performance Evaluation of Despeckling Filters.

    Science.gov (United States)

    Biradar, Nagashettappa; Dewal, M L; Rohit, ManojKumar; Gowre, Sanjaykumar; Gundge, Yogesh

    2016-01-01

    The speckle noise is inherent to transthoracic echocardiographic images. A standard noise-free reference echocardiographic image does not exist. The evaluation of filters based on the traditional parameters such as peak signal-to-noise ratio, mean square error, and structural similarity index may not reflect the true filter performance on echocardiographic images. Therefore, the performance of despeckling can be evaluated using blind assessment metrics like the speckle suppression index, speckle suppression and mean preservation index (SMPI), and beta metric. The need for noise-free reference image is overcome using these three parameters. This paper presents a comprehensive analysis and evaluation of eleven types of despeckling filters for echocardiographic images in terms of blind and traditional performance parameters along with clinical validation. The noise is effectively suppressed using the logarithmic neighborhood shrinkage (NeighShrink) embedded with Stein's unbiased risk estimation (SURE). The SMPI is three times more effective compared to the wavelet based generalized likelihood estimation approach. The quantitative evaluation and clinical validation reveal that the filters such as the nonlocal mean, posterior sampling based Bayesian estimation, hybrid median, and probabilistic patch based filters are acceptable whereas median, anisotropic diffusion, fuzzy, and Ripplet nonlinear approximation filters have limited applications for echocardiographic images. PMID:27298618

  12. BLUES from Music: BLind Underdetermined Extraction of Sources from Music

    DEFF Research Database (Denmark)

    Pedersen, Michael Syskind; Lehn-Schiøler, Tue; Larsen, Jan

    2006-01-01

    In this paper we propose to use an instantaneous ICA method (BLUES) to separate the instruments in a real music stereo recording. We combine two strong separation techniques to segregate instruments from a mixture: ICA and binary time-frequency masking. By combining the methods, we are able to make...

  13. Coupled Blind Signal Separation and Spectroscopic Database Fitting of the Mid Infrared PAH Features

    CERN Document Server

    Rosenberg, M J F; Boersma, C; Allamandola, L J; Tielens, A G G M

    2011-01-01

    The aromatic infrared bands (AIBs) observed in the mid infrared spectrum are attributed to Polycyclic Aromatic Hydrocarbons (PAHs). We observe the NGC 7023-North West (NW) PDR in the mid-infrared (10 - 19.5 micron) using the Infrared Spectrometer (IRS), on board Spitzer. Clear variations are observed in the spectra, most notably the ratio of the 11.0 to 11.2 micron bands, the peak position of the 11.2 and 12.0 micron bands, and the degree of asymmetry of the 11.2 micron band. The observed variations appear to change as a function of position within the PDR. We aim to explain these variations by a change in the abundances of the emitting components of the PDR. A Blind Signal Separation (BSS) method, i.e. a Non-Negative Matrix Factorization algorithm is applied to separate the observed spectrum into components. Using the NASA Ames PAH IR Spectroscopic Database, these extracted signals are fit. The observed signals alone were also fit using the database and these components are compared to the BSS components. Th...

  14. BAYESIAN SEMI-BLIND COMPONENT SEPARATION FOR FOREGROUND REMOVAL IN INTERFEROMETRIC 21 cm OBSERVATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Le; Timbie, Peter T. [Department of Physics, University of Wisconsin, Madison, WI 53706 (United States); Bunn, Emory F. [Physics Department, University of Richmond, Richmond, VA 23173 (United States); Karakci, Ata; Korotkov, Andrei; Tucker, Gregory S. [Department of Physics, Brown University, 182 Hope Street, Providence, RI 02912 (United States); Sutter, P. M. [Center for Cosmology and Astro-Particle Physics, Ohio State University, Columbus, OH 43210 (United States); Wandelt, Benjamin D., E-mail: lzhang263@wisc.edu [Department of Physics, University of Illinois at Urbana-Champaign, 1110 W Green Street, Urbana, IL 61801 (United States)

    2016-01-15

    In this paper, we present a new Bayesian semi-blind approach for foreground removal in observations of the 21 cm signal measured by interferometers. The technique, which we call H i Expectation–Maximization Independent Component Analysis (HIEMICA), is an extension of the Independent Component Analysis technique developed for two-dimensional (2D) cosmic microwave background maps to three-dimensional (3D) 21 cm cosmological signals measured by interferometers. This technique provides a fully Bayesian inference of power spectra and maps and separates the foregrounds from the signal based on the diversity of their power spectra. Relying only on the statistical independence of the components, this approach can jointly estimate the 3D power spectrum of the 21 cm signal, as well as the 2D angular power spectrum and the frequency dependence of each foreground component, without any prior assumptions about the foregrounds. This approach has been tested extensively by applying it to mock data from interferometric 21 cm intensity mapping observations under idealized assumptions of instrumental effects. We also discuss the impact when the noise properties are not known completely. As a first step toward solving the 21 cm power spectrum analysis problem, we compare the semi-blind HIEMICA technique to the commonly used Principal Component Analysis. Under the same idealized circumstances, the proposed technique provides significantly improved recovery of the power spectrum. This technique can be applied in a straightforward manner to all 21 cm interferometric observations, including epoch of reionization measurements, and can be extended to single-dish observations as well.

  15. Separating Underdetermined Convolutive Speech Mixtures

    DEFF Research Database (Denmark)

    Pedersen, Michael Syskind; Wang, DeLiang; Larsen, Jan;

    2006-01-01

    a method for underdetermined blind source separation of convolutive mixtures. The proposed framework is applicable for separation of instantaneous as well as convolutive speech mixtures. It is possible to iteratively extract each speech signal from the mixture by combining blind source separation...

  16. Semi-blind source extraction algorithm for fetal electrocardiogram based on generalized autocorrelations and reference signals

    Science.gov (United States)

    Zhang, Hongjuan; Shi, Zhenwei; Guo, Chonghui; Feng, Enmin

    2009-01-01

    Blind source extraction (BSE) has become one of the promising methods in the field of signal processing and analysis, which only desires to extract "interesting" source signals with specific stochastic property or features so as to save lots of computing time and resources. This paper addresses BSE problem, in which desired source signals have some available reference signals. Based on this prior information, we develop an objective function for extraction of temporally correlated sources. Maximizing this objective function, a semi-blind source extraction fixed-point algorithm is proposed. Simulations on artificial electrocardiograph (ECG) signals and the real-world ECG data demonstrate the better performance of the new algorithm. Moreover, comparisons with existing algorithms further indicate the validity of our new algorithm, and also show its robustness to the estimated error of time delay.

  17. Magnetic source separation in Earth's outer core.

    Science.gov (United States)

    Hoffman, Kenneth A; Singer, Brad S

    2008-09-26

    We present evidence that the source of Earth's axial dipole field is largely independent from the sources responsible for the rest of the geomagnetic field, the so-called nonaxial dipole (NAD) field. Support for this claim comes from correlations between the structure of the historic field and the behavior of the paleomagnetic field recorded in precisely dated lavas at those times when the axial dipole was especially weak or nearly absent. It is argued that a "stratification" of magnetic sources exists in the fluid core such that the axial dipole is the only observed field component that is nearly immune from the influence exerted by the lowermost mantle. It follows that subsequent work on spherical harmonic-based field descriptions may now incorporate an understanding of a dichotomy of spatial-temporal dynamo processes. PMID:18818352

  18. Measurment of gas-liquid two-phase slug flow with a Venturi meter based on blind source separation☆

    Institute of Scientific and Technical Information of China (English)

    Weiwei Wang; Xiao Liang; Mingzhu Zhang

    2015-01-01

    We propose a novel flow measurement method for gas–liquid two-phase slug flow by using the blind source sep-aration technique. The flow measurement model is established based on the fluctuation characteristics of differ-ential pressure (DP) signals measured from a Venturi meter. It is demonstrated that DP signals of two-phase flow are a linear mixture of DP signals of single phase fluids. The measurement model is a combination of throttle re-lationship and blind source separation model. In addition, we estimate the mixture matrix using the independent component analysis (ICA) technique. The mixture matrix could be described using the variances of two DP sig-nals acquired from two Venturi meters. The validity of the proposed model was tested in the gas–liquid two-phase flow loop facility. Experimental results showed that for most slug flow the relative error is within 10%. We also find that the mixture matrix is beneficial to investigate the flow mechanism of gas–liquid two-phase flow.

  19. Tungsten moderator of Venetian blinds- and honeycomb-type for the slow positron source on hard synchrotron radiation of SPring-8 storage ring

    Science.gov (United States)

    Plokhoi, V. V.; Kandiev, Ya. Z.; Samarin, S. I.; Malyshkin, G. N.; Baidin, G. V.; Litvinenko, I. A.; Nikitin, V. P.

    2001-09-01

    The paper considers designs of moderators where fast positron stopping medium consists of very fine tungsten strips separated by vacuum gaps and the strips are arranged into Venetian blinds- or honeycomb-type structures. Moderator efficiency is evaluated through Monte-Carlo simulations. According to the maximal estimate, the efficiency of conversion of fast positrons into slow ones in the Venetian blinds and honeycomb-type moderators is ˜5×10 -3 for the reasonable thickness of the tungsten foil. If such moderator is used, the intensity of slow positron source on the hard synchrotron of SPring-8 storage ring can reach the level of ˜5×10 10 e +/s.

  20. 基于新概率密度函数的ICA盲源分离%ICA Blind Signal Separation Based on a New Probability Density Function

    Institute of Scientific and Technical Information of China (English)

    张娟娟; 邸双亮

    2014-01-01

    This paper is concerned with the blind source separation (BSS) problem of super-Gaussian and sub-Gaussian mixed signal by using the maximum likelihood method, which is based on independent component analysis (ICA) method. In this paper, we construct a new type of probability density function (PDF) which is different from the already existing PDF used to separate mixed signals in the previously published papers. Applying the new constructed PDF to estimate probability density of super-Gaussian and sub-Gaussian signals (assuming the source signals are independent of each other), it is not necessary to change the parameter values artificially, and the separation work may be performed adaptively. Numerical experiments verify the feasibility of the newly constructed PDF, and the convergence time and the separation effect are improved compared with the original algorithm.%基于独立分量分析(Independent Component Analysis, ICA),利用极大似然估计法,研究了超高斯和亚高斯的混合信号的盲源分离(Blind Sources Separation, BSS)问题。文中构造了一种新的、不同于以往文章中用来分离混合信号的概率密度函数(Probability Density Function, PDF)。新构造的PDF无需改变函数中的参数值,可用来对于超高斯和亚高斯信号的概率密度进行估计(假设未知源信号是相互独立的)。数值实验验证了新构造的PDF的可行性,与原算法相比,收敛时间和分离效果都得到了较大的改善。

  1. An efficient semi-blind source extraction algorithm and its applications to biomedical signal extraction

    Institute of Scientific and Technical Information of China (English)

    YE YaLan; SHEU Phillip C-Y; ZENG JiaZhi; WANG Gang; LU Ke

    2009-01-01

    In many applications, such as biomedical engineering, it is often required to extract a desired signal instead of all source signals. This can be achieved by blind source extraction (BSE) or semi-blind source extraction, which is a powerful technique emerging from the neural network field. In this paper, we propose an efficient semi-blind source extraction algorithm to extract a desired source signal as its first output signal by using a priori information about its kurtosis range. The algorithm is robust to outliers and spiky noise because of adopting a classical robust contrast function. And it is also robust to the estimation errors of the kurtoaia range of the desired signal providing the estimation errors are not large. The algorithm has good extraction performance, even in some poor situations when the kurtosis values of some source signals are very close to each other. Its convergence stability and robustness are theoretically analyzed. Simulations and experiments on artificial generated data and real-world data have confirmed these results.

  2. Blind estimation of the number of speech source in reverberant multisource scenarios based on binaural signals

    DEFF Research Database (Denmark)

    May, Tobias; van de Par, Steven

    2012-01-01

    In this paper we present a new approach for estimating the number of active speech sources in the presence of interfering noise sources and reverberation. First, a binaural front-end is used to detect the spatial positions of all active sound sources, resulting in a binary mask for each candidate...... on a support vector machine (SVM) classifier. A systematic analysis shows that the proposed algorithm is able to blindly determine the number and the corresponding spatial positions of speech sources in multisource scenarios and generalizes well to unknown acoustic conditions...

  3. Precise Measurement of Separation Between Two Spherical Source Masses

    Institute of Scientific and Technical Information of China (English)

    陈德才; 罗俊; 胡忠坤; 赵亮

    2004-01-01

    A driving gauge method is performed to determine the separation between two spherical source masses in the measurement of Newtonian gravitational constant G. The experimental result shows that the uncertainty of determining the separation is about 0.35μm, which would contribute an uncertainty of 7.3ppm to the value of G.

  4. Source separation of household waste: A case study in China

    International Nuclear Information System (INIS)

    A pilot program concerning source separation of household waste was launched in Hangzhou, capital city of Zhejiang province, China. Detailed investigations on the composition and properties of household waste in the experimental communities revealed that high water content and high percentage of food waste are the main limiting factors in the recovery of recyclables, especially paper from household waste, and the main contributors to the high cost and low efficiency of waste disposal. On the basis of the investigation, a novel source separation method, according to which household waste was classified as food waste, dry waste and harmful waste, was proposed and performed in four selected communities. In addition, a corresponding household waste management system that involves all stakeholders, a recovery system and a mechanical dehydration system for food waste were constituted to promote source separation activity. Performances and the questionnaire survey results showed that the active support and investment of a real estate company and a community residential committee play important roles in enhancing public participation and awareness of the importance of waste source separation. In comparison with the conventional mixed collection and transportation system of household waste, the established source separation and management system is cost-effective. It could be extended to the entire city and used by other cities in China as a source of reference

  5. Separation of synchronous sources through phase locked matrix factorization.

    Science.gov (United States)

    Almeida, Miguel S B; Vigário, Ricardo; Bioucas-Dias, José

    2014-10-01

    In this paper, we study the separation of synchronous sources (SSS) problem, which deals with the separation of sources whose phases are synchronous. This problem cannot be addressed through independent component analysis methods because synchronous sources are statistically dependent. We present a two-step algorithm, called phase locked matrix factorization (PLMF), to perform SSS. We also show that SSS is identifiable under some assumptions and that any global minimum of PLMFs cost function is a desirable solution for SSS. We extensively study the algorithm on simulated data and conclude that it can perform SSS with various numbers of sources and sensors and with various phase lags between the sources, both in the ideal (i.e., perfectly synchronous and nonnoisy) case, and with various levels of additive noise in the observed signals and of phase jitter in the sources. PMID:25291741

  6. Nonnegative least-correlated component analysis for separation of dependent sources by volume maximization.

    Science.gov (United States)

    Wang, Fa-Yu; Chi, Chong-Yung; Chan, Tsung-Han; Wang, Yue

    2010-05-01

    Although significant efforts have been made in developing nonnegative blind source separation techniques, accurate separation of positive yet dependent sources remains a challenging task. In this paper, a joint correlation function of multiple signals is proposed to reveal and confirm that the observations after nonnegative mixing would have higher joint correlation than the original unknown sources. Accordingly, a new nonnegative least-correlated component analysis (n/LCA) method is proposed to design the unmixing matrix by minimizing the joint correlation function among the estimated nonnegative sources. In addition to a closed-form solution for unmixing two mixtures of two sources, the general algorithm of n/LCA for the multisource case is developed based on an iterative volume maximization (IVM) principle and linear programming. The source identifiability and required conditions are discussed and proven. The proposed n/LCA algorithm, denoted by n/LCA-IVM, is evaluated with both simulation data and real biomedical data to demonstrate its superior performance over several existing benchmark methods. PMID:20299711

  7. Common source-multiple load vs. separate source-individual load photovoltaic system

    Science.gov (United States)

    Appelbaum, Joseph

    1989-01-01

    A comparison of system performance is made for two possible system setups: (1) individual loads powered by separate solar cell sources; and (2) multiple loads powered by a common solar cell source. A proof for resistive loads is given that shows the advantage of a common source over a separate source photovoltaic system for a large range of loads. For identical loads, both systems perform the same.

  8. Extended Nonnegative Tensor Factorisation Models for Musical Sound Source Separation

    Directory of Open Access Journals (Sweden)

    Derry FitzGerald

    2008-01-01

    Full Text Available Recently, shift-invariant tensor factorisation algorithms have been proposed for the purposes of sound source separation of pitched musical instruments. However, in practice, existing algorithms require the use of log-frequency spectrograms to allow shift invariance in frequency which causes problems when attempting to resynthesise the separated sources. Further, it is difficult to impose harmonicity constraints on the recovered basis functions. This paper proposes a new additive synthesis-based approach which allows the use of linear-frequency spectrograms as well as imposing strict harmonic constraints, resulting in an improved model. Further, these additional constraints allow the addition of a source filter model to the factorisation framework, and an extended model which is capable of separating mixtures of pitched and percussive instruments simultaneously.

  9. Separation of core and crustal magnetic field sources

    Science.gov (United States)

    Shure, L.; Parker, R. L.; Langel, R. A.

    1985-01-01

    Fluid motions in the electrically conducting core and magnetized crustal rocks are the two major sources of the magnetic field observed on or slightly above the Earth's surface. The exact separation of these two contributions is not possible without imposing a priori assumptions about the internal source distribution. Nonetheless models like these were developed for hundreds of years Gauss' method, least squares analysis with a truncated spherical harmonic expansion was the method of choice for more than 100 years although he did not address separation of core and crustal sources, but rather internal versus external ones. Using some arbitrary criterion for appropriate truncation level, we now extrapolate downward core field models through the (approximately) insulating mantle. Unfortunately our view can change dramatically depending on the degree of truncation for describing core sources.

  10. Simultaneous Blind Separation and Recognition of Speech Mixtures Using Two Microphones to Control a Robot Cleaner

    Directory of Open Access Journals (Sweden)

    Heungkyu Lee

    2013-02-01

    Full Text Available This paper proposes a method for the simultaneous separation and recognition of speech mixtures in noisy environments using two‐channel based independent vector analysis (IVA on a home‐robot cleaner. The issues to be considered in our target application are speech recognition at a distance and noise removal to cope with a variety of noises, including TV sounds, air conditioners, babble, and so on, that can occur in a house, where people can utter a voice command to control a robot cleaner at any time and at any location, even while a robot cleaner is moving. Thus, the system should always be in a recognition‐ready state to promptly recognize a spoken word at any time, and the false acceptance rate should be lower. To cope with these issues, the keyword spotting technique is applied. In addition, a microphone alignment method and a model‐based real‐time IVA approach are proposed to effectively and simultaneously process the speech and noise sources, as well as to cover 360‐degree directions irrespective of distance. From the experimental evaluations, we show that the proposed method is robust in terms of speech recognition accuracy, even when the speaker location is unfixed and changes all the time. In addition, the proposed method shows good performance in severely noisy environments.

  11. Convolutive Frequency-Domain Blind Interference-Signal Separation Algorithm Based on IVA%基于IVA的卷积混合频域盲扰信分离算法研究

    Institute of Scientific and Technical Information of China (English)

    文威; 张杭

    2012-01-01

    Blind interference-signal separation technique is the application of Blind Source Separation (BSS) in anti-jamming. This paper introduced a frequency-domain convolutive blind interference-signal separation algorithm based on Independent Vector Analysis (IVA), which prevents permutation ambiguity and acquires better separation performance. Simulation results indicate that this algorithm can separate BPSK signal and a variety of interference, and has cer- tain anti-interference ability.%盲扰信分离是盲源分离算法在无线通信抗干扰中的应用。文章将独立向量分析(IVA)引入到卷积混合频域盲扰信分离算法中,克服了频域方法存在顺序不确定性和分离效果不佳的缺陷。仿真实验表明该算法的有效性,采用该算法实现了卷积混合条件下BPSK信号与多种干扰的扰信分离,具有一定的抗干扰能力。

  12. Underdetermined blind separation based on ant colony clustering%蚁群聚类的欠定盲源分离方法

    Institute of Scientific and Technical Information of China (English)

    王放; 何选森

    2013-01-01

    利用欠定盲源分离情况下稀疏源信号具有直线聚类的特点,提出了一种估计混叠矩阵的新方法。通过对混叠信号进行标准化处理,使混叠信号形成球形簇,将线性聚类转变成致密聚类;利用蚁群聚类算法对其进行搜索得到聚类中心,从而获得对混叠矩阵的精确估计。该方法能实现源信号数目未知情况下的欠定盲源分离,且能推广到三路或更多路观测信号的情况。对语音信号的仿真结果证明,该方法能精确地分离和恢复原始信号。%Taking advantage of the straight line clustering of the sparse source signals in underdetermined blind separation, a method of the mixing matrix estimation is proposed. The aliasing signals are standardized and the aliasing signals are formed spherical cluster, so the linear cluster is turned into density cluster. And then the clustering center is searched and obtained by using the ant clustering algorithm. The aliasing matrix and the source signals are accurately evaluated. The proposed algorithm can separate the source signals in which the number is unknown and it is also effective to separate three or more observed signals. The simulation results of speech signals show that this method can precisely separate and restore the original signals.

  13. Source separation and clustering of phase-locked subspaces.

    Science.gov (United States)

    Almeida, Miguel; Schleimer, Jan-Hendrik; Bioucas-Dias, José Mario; Vigário, Ricardo

    2011-09-01

    It has been proven that there are synchrony (or phase-locking) phenomena present in multiple oscillating systems such as electrical circuits, lasers, chemical reactions, and human neurons. If the measurements of these systems cannot detect the individual oscillators but rather a superposition of them, as in brain electrophysiological signals (electro- and magneoencephalogram), spurious phase locking will be detected. Current source-extraction techniques attempt to undo this superposition by assuming properties on the data, which are not valid when underlying sources are phase-locked. Statistical independence of the sources is one such invalid assumption, as phase-locked sources are dependent. In this paper, we introduce methods for source separation and clustering which make adequate assumptions for data where synchrony is present, and show with simulated data that they perform well even in cases where independent component analysis and other well-known source-separation methods fail. The results in this paper provide a proof of concept that synchrony-based techniques are useful for low-noise applications. PMID:21791409

  14. Asymmetric Joint Source-Channel Coding for Correlated Sources with Blind HMM Estimation at the Receiver

    Directory of Open Access Journals (Sweden)

    Ser Javier Del

    2005-01-01

    Full Text Available We consider the case of two correlated sources, and . The correlation between them has memory, and it is modelled by a hidden Markov chain. The paper studies the problem of reliable communication of the information sent by the source over an additive white Gaussian noise (AWGN channel when the output of the other source is available as side information at the receiver. We assume that the receiver has no a priori knowledge of the correlation statistics between the sources. In particular, we propose the use of a turbo code for joint source-channel coding of the source . The joint decoder uses an iterative scheme where the unknown parameters of the correlation model are estimated jointly within the decoding process. It is shown that reliable communication is possible at signal-to-noise ratios close to the theoretical limits set by the combination of Shannon and Slepian-Wolf theorems.

  15. Asymmetric Joint Source-Channel Coding for Correlated Sources with Blind HMM Estimation at the Receiver

    Directory of Open Access Journals (Sweden)

    Ser Javier Del

    2005-01-01

    Full Text Available We consider the case of two correlated sources, S 1 and S 2 . The correlation between them has memory, and it is modelled by a hidden Markov chain. The paper studies the problem of reliable communication of the information sent by the source S 1 over an additive white Gaussian noise (AWGN channel when the output of the other source S 2 is available as side information at the receiver. We assume that the receiver has no a priori knowledge of the correlation statistics between the sources. In particular, we propose the use of a turbo code for joint source-channel coding of the source S 1 . The joint decoder uses an iterative scheme where the unknown parameters of the correlation model are estimated jointly within the decoding process. It is shown that reliable communication is possible at signal-to-noise ratios close to the theoretical limits set by the combination of Shannon and Slepian-Wolf theorems.

  16. Waste Separation Press (WSP): a mechanical pretreatment option for organic waste from source separation.

    Science.gov (United States)

    Jank, Anna; Müller, Wolfgang; Schneider, Irene; Gerke, Frederic; Bockreis, Anke

    2015-05-01

    An efficient biological treatment of source separated organic waste from household kitchens and gardens (biowaste) requires an adequate upfront mechanical preparation which possibly includes a hand sorting for the separation of contaminants. In this work untreated biowaste from households and gardens and the screen overflow >60mm of the same waste were mechanically treated by a Waste Separation Press (WSP). The WSP separates the waste into a wet fraction for biological treatment and a fraction of dry contaminants for incineration. The results show that it is possible to replace a hand sorting of contaminants, the milling and a screening of organic waste before the biological treatment by using the WSP. A special focus was put on the contaminants separation. The separation of plastic film from the untreated biowaste was 67% and the separation rate of glass was about 92%. About 90% of the organics were transferred to the fraction for further biological treatment. When treating the screen overflow >60mm with the WSP 86% of the plastic film and 88% of the glass were transferred to the contaminants fraction. 32% of the organic was transferred to the contaminants fraction and thereby lost for a further biological treatment. Additionally it was calculated that national standards for glass contaminants in compost can be met when using the WSP to mechanically treat the total biowaste. The loss of biogas by transferring biodegradable organics to the contaminants fraction was about 11% when preparing the untreated biowaste with the WSP. PMID:25761398

  17. Source Separation with One Ear: Proposition for an Anthropomorphic Approach

    Directory of Open Access Journals (Sweden)

    Ramin Pichevar

    2005-06-01

    Full Text Available We present an example of an anthropomorphic approach, in which auditory-based cues are combined with temporal correlation to implement a source separation system. The auditory features are based on spectral amplitude modulation and energy information obtained through 256 cochlear filters. Segmentation and binding of auditory objects are performed with a two-layered spiking neural network. The first layer performs the segmentation of the auditory images into objects, while the second layer binds the auditory objects belonging to the same source. The binding is further used to generate a mask (binary gain to suppress the undesired sources from the original signal. Results are presented for a double-voiced (2 speakers speech segment and for sentences corrupted with different noise sources. Comparative results are also given using PESQ (perceptual evaluation of speech quality scores. The spiking neural network is fully adaptive and unsupervised.

  18. Tungsten moderator of Venetian blinds- and honeycomb-type for the slow positron source on hard synchrotron radiation of SPring-8 storage ring

    CERN Document Server

    Plokhoi, V V; Samarin, S I; Malyshkin, G N; Baidin, G V; Litvinenko, I A; Nikitin, V P

    2001-01-01

    The paper considers designs of moderators where fast positron stopping medium consists of very fine tungsten strips separated by vacuum gaps and the strips are arranged into Venetian blinds- or honeycomb-type structures. Moderator efficiency is evaluated through Monte-Carlo simulations. According to the maximal estimate, the efficiency of conversion of fast positrons into slow ones in the Venetian blinds and honeycomb-type moderators is approx 5x10 sup - sup 3 for the reasonable thickness of the tungsten foil. If such moderator is used, the intensity of slow positron source on the hard synchrotron of SPring-8 storage ring can reach the level of approx 5x10 sup 1 sup 0 e sup + /s.

  19. Blind noisy image separation based on a new robust independent component analysis network

    Institute of Scientific and Technical Information of China (English)

    Jian Ji; Zheng Tian

    2006-01-01

    The separation of noisy image is a very exciting area of research, especially when no prior information is available about the noisy image. In this paper, we propose a robust independent component analysis(ICA) network for separation images contaminated with high-level additive noise or outliers. We reduce the power of additive noise by adding outlier rejection rule in ICA. Extensive computer simulations confirm robustness and the excellent performance of the resulting algorithms.

  20. Underdetermined Blind Separation of Non-sparse Signals and Its Application in Speech Separation%非稀疏欠定盲分离及其在语音分离中的应用

    Institute of Scientific and Technical Information of China (English)

    陈永强; 王宏霞

    2012-01-01

    A method applicable to underdetermined blind separation of non-sparse signals is proposed, which is based on the Markov chain Monte Carlo (MCMC)Bayesian framework. The generalized Gaussian distribution (GGD) is used to model the source signals distribution, the model parameters and hidden variables are estimated by MCMC sampling to obtain the least mean square error estimation (MMSE) of source signals, by which the problem is solved that the GGD parameter estimation easily falls into a local extremum point and has poor robustness. Making use of the local stationarity of speech, a blind separation method based on non-sparse judgment criterions is proposed to enhance speech separation accuracy, which separates the speech in the non-sparse zone by MCMC sampling. Computer simulation shows that the proposed method can improve separation performance of non-sparse and speech signals, it also has better robustness.%本文提出一种基于马尔科夫链蒙特卡洛方法(MCMC)的贝叶斯非稀疏盲源分离算法.用广义高斯分布(GGD)来拟合源信号的分布,通过MCMC抽样得到GGD参数和隐变量的估计,并由此得到源信号的最小均方误差估计(MMSE),解决了GGD参数估计容易陷入局部极值点、鲁棒性差的问题.根据语音信号的局部平稳性,提出基于非稀疏度评判准则的盲分离算法,用MCMC方法分离非稀疏区的语音信号,进一步提高了语音信号分离精度.仿真实验证明,本文方法改善了非稀疏信号和语音信号的分离效果,而且具有更好的鲁棒性.

  1. Blind Separation of Twin Fetal Heartbeats in an Electrocardiogram using the Fractional Fourier Transform

    Directory of Open Access Journals (Sweden)

    Seema Sud

    2016-04-01

    Full Text Available The Fractional Fourier Transform (FrFT has been used for signal separation in numerous applications, such as speech, radar, and image processing. It is a useful signal processing tool that enables significantly greater signal separation by rotating signals in a time-frequency plane known as the Wigner Distribution (WD where they may be totally separable, when they are not separable in the time or frequency domains alone. In this paper, we apply the FrFT to the problem of separating the heartbeats of twin fetuses, as seen on an electrocardiogram (ECG, from each other. Most techniques fail here because the two heartbeat patterns are similar. The proposed algorithm takes advantage of the fact that two or more fetal heartbeats can be approximated as damped, chirp signals and may be slightly offset in time or amplitude. Thus, the WDs of the two signals will be slightly different from each other. By finding and rotating to the proper axis in the WD plane, where the chirp heartbeats become narrowband, separable signals, we can notch much of the weaker heartbeat to extract the stronger one. The estimate of the stronger signal is then subtracted from the ECG signal to obtain the weaker one. We show that the technique operates well using simulations, even when the two heartbeats are nearly equal in power. Specifically, we show that the mean-square error (MSE between the true heartbeats and the estimated ones are only on the order of 10−4 −10−3 . This method will enable identification of problems in an unborn child early in when the pregnant mother is expecting twins

  2. STUDY ON APPLICATION OF BLIND SOURCE SEPARATION AND WAVELET DE-NOISING IN RUBBING FAULT ACCOUSTIC SIGNAL ANALYSIS%盲源分离和小波消噪在碰摩声频信号分析中的应用研究

    Institute of Scientific and Technical Information of China (English)

    李熠; 何永勇; 李志农; 褚福磊

    2005-01-01

    碰摩是现代旋转机械运行中常见的一种故障,文中尝试从声频信号的角度对碰摩故障进行分析.在实际环境中,碰摩声频信号常常受到噪声的污染,文中将盲源分离和小波消噪方法相结合,使用P.S.(pre-separation de-noising, separation)和P.S.P.(pre-separation de-noising, separation, post-separation de-noising)方法对碰摩声频信号进行分析处理,大大提高了信号的信噪比,取得了比较理想的实验结果.

  3. Radio Searches of Fermi LAT Sources and Blind Search Pulsars: The Fermi Pulsar Search Consortium

    CERN Document Server

    Ray, P S; Parent, D; Bhattacharya, D; Bhattacharyya, B; Camilo, F; Cognard, I; Theureau, G; Ferrara, E C; Harding, A K; Thompson, D J; Freire, P C C; Guillemot, L; Gupta, Y; Roy, J; Hessels, J W T; Johnston, S; Keith, M; Shannon, R; Kerr, M; Michelson, P F; Romani, R W; Kramer, M; McLaughlin, M A; Ransom, S M; Roberts, M S E; Parkinson, P M Saz; Ziegler, M; Smith, D A; Stappers, B W; Weltevrede, P; Wood, K S

    2012-01-01

    We present a summary of the Fermi Pulsar Search Consortium (PSC), an international collaboration of radio astronomers and members of the Large Area Telescope (LAT) collaboration, whose goal is to organize radio follow-up observations of Fermi pulsars and pulsar candidates among the LAT gamma-ray source population. The PSC includes pulsar observers with expertise using the world's largest radio telescopes that together cover the full sky. We have performed very deep observations of all 35 pulsars discovered in blind frequency searches of the LAT data, resulting in the discovery of radio pulsations from four of them. We have also searched over 300 LAT gamma-ray sources that do not have strong associations with known gamma-ray emitting source classes and have pulsar-like spectra and variability characteristics. These searches have led to the discovery of a total of 43 new radio millisecond pulsars (MSPs) and four normal pulsars. These discoveries greatly increase the known population of MSPs in the Galactic disk...

  4. Simultaneous Blind Separation and Recognition of Speech Mixtures Using Two Microphones to Control a Robot Cleaner

    OpenAIRE

    Heungkyu Lee

    2013-01-01

    This paper proposes a method for the simultaneous separation and recognition of speech mixtures in noisy environments using two‐channel based independent vector analysis (IVA) on a home‐robot cleaner. The issues to be considered in our target application are speech recognition at a distance and noise removal to cope with a variety of noises, including TV sounds, air conditioners, babble, and so on, that can occur in a house, where people can utter a voice command to control a robot cleaner at...

  5. The Leuven isotope separator on-line laser ion source

    CERN Document Server

    Kudryavtsev, Y; Franchoo, S; Huyse, M; Gentens, J; Kruglov, K; Müller, W F; Prasad, N V S; Raabe, R; Reusen, I; Van den Bergh, P; Van Duppen, P; Van Roosbroeck, J; Vermeeren, L; Weissman, L

    2002-01-01

    An element-selective laser ion source has been used to produce beams of exotic radioactive nuclei and to study their decay properties. The operational principle of the ion source is based on selective resonant laser ionization of nuclear reaction products thermalized and neutralized in a noble gas at high pressure. The ion source has been installed at the Leuven Isotope Separator On-Line (LISOL), which is coupled on-line to the cyclotron accelerator at Louvain-la-Neuve. sup 5 sup 4 sup , sup 5 sup 5 Ni and sup 5 sup 4 sup , sup 5 sup 5 Co isotopes were produced in light-ion-induced fusion reactions. Exotic nickel, cobalt and copper nuclei were produced in proton-induced fission of sup 2 sup 3 sup 8 U. The b decay of the sup 6 sup 8 sup - sup 7 sup 4 Ni, sup 6 sup 7 sup - sup 7 sup 0 Co, sup 7 sup 0 sup - sup 7 sup 5 Cu and sup 1 sup 1 sup 0 sup - sup 1 sup 1 sup 4 Rh isotopes has been studied by means of beta-gamma and gamma-gamma spectroscopy. Recently, the laser ion source has been used to produce neutron-d...

  6. Algorithms for Blind Components Separation and Extraction from the Time-Frequency Distribution of Their Mixture

    Directory of Open Access Journals (Sweden)

    B. Barkat

    2004-10-01

    Full Text Available We propose novel algorithms to select and extract separately all the components, using the time-frequency distribution (TFD, of a given multicomponent frequency-modulated (FM signal. These algorithms do not use any a priori information about the various components. However, their performances highly depend on the cross-terms suppression ability and high time-frequency resolution of the considered TFD. To illustrate the usefulness of the proposed algorithms, we applied them for the estimation of the instantaneous frequency coefficients of a multicomponent signal and the results are compared with those of the higher-order ambiguity function (HAF algorithm. Monte Carlo simulation results show the superiority of the proposed algorithms over the HAF.

  7. A multilevel voltage-source inverter with separate dc sources for static var generation

    Energy Technology Data Exchange (ETDEWEB)

    Peng, Fang Zheng [Tennessee Univ., Knoxville, TN (United States)]|[Oak Ridge National Lab., TN (United States); Lai, Jih-Sheng; McKeever, J.; VanCoevering, J. [Oak Ridge National Lab., TN (United States)

    1995-09-01

    A new multilevel voltage-source inverter with a separate dc sources is proposed for high-voltage, high-power applications, such as flexible ac transmission systems (FACTS) including static var generation (SVG), power line conditioning, series compensation, phase shifting, voltage balancing, fuel cell and photovoltaic utility systems interfacing, etc. The new M-level inverter consists of (M-1)/2 single phase full bridges in which each bridge has its own separate dc source. This inverter can generate almost sinusoidal waveform voltage with only one time switching per cycle as the number of levels increases. It can solve the problems of conventional transformer-based multipulse inverters and the problems of the multilevel diode-clamped inverter and the multilevel flying capacitor inverter. To demonstrate the superiority of the new inverter, a SVG system using the new inverter topology is discussed through analysis, simulation and experiment.

  8. The Effects of Environmental Management Systems on Source Separation in the Work and Home Settings

    Directory of Open Access Journals (Sweden)

    Chris von Borgstede

    2012-06-01

    Full Text Available Measures that challenge the generation of waste are needed to address the global problem of the increasing volumes of waste that are generated in both private homes and workplaces. Source separation at the workplace is commonly implemented by environmental management systems (EMS. In the present study, the relationship between source separation at work and at home was investigated. A questionnaire that maps psychological and behavioural predictors of source separation was distributed to employees at different workplaces. The results show that respondents with awareness of EMS report higher levels of source separation at work, stronger environmental concern, personal and social norms, and perceive source separation to be less difficult. Furthermore, the results support the notion that after the adoption of EMS at the workplace, source separation at work spills over into source separation in the household. The potential implications for environmental management systems are discussed.

  9. Using the FASST source separation toolbox for noise robust speech recognition

    OpenAIRE

    Ozerov, Alexey; Vincent, Emmanuel

    2011-01-01

    We describe our submission to the 2011 CHiME Speech Separation and Recognition Challenge. Our speech separation algorithm was built using the Flexible Audio Source Separation Toolbox (FASST) we developed recently. This toolbox is an implementation of a general flexible framework based on a library of structured source models that enable the incorporation of prior knowledge about a source separation problem via user-specifiable constraints. We show how to use FASST to develop an efficient spee...

  10. New method for signal encryption using blind source separation based on subband decomposition

    Institute of Scientific and Technical Information of China (English)

    Zuyuan Yang; Guoxu Zhou; Zongze Wu; Jinlong Zhang

    2008-01-01

    A novel cryptosystem based on subband decomposition independent component analysis (SDICA) is proposed in this work, where no assumption of independence for the ciphers and the plaintexts is required. In the proposed cryptosystem, the encryption is asynchronous, i.e. the plaintexts are mixed mutually firstly and then mixed with the ciphers. In addition, the decryption is asynchronous, such that the decryption accuracy of the plaintexts can be enhanced. Some special information about the original mixing matrix is used for solving the indeterminacy of the permutation and scale of columns of the recovered mixing matrix in SDICA, instead of the characteristics of the plaintexts. Simulations are given to illustrate security and availability of our cryptosystem.

  11. Online Artifact Removal for Brain-Computer Interfaces Using Support Vector Machines and Blind Source Separation

    Directory of Open Access Journals (Sweden)

    Sebastian Halder

    2007-01-01

    that are designed for online usage. In order to select a suitable BSS/ICA method, three ICA algorithms (JADE, Infomax, and FastICA and one BSS algorithm (AMUSE are evaluated to determine their ability to isolate electromyographic (EMG and electrooculographic (EOG artifacts into individual components. An implementation of the selected BSS/ICA method with SVMs trained to classify EMG and EOG artifacts, which enables the usage of the method as a filter in measurements with online feedback, is described. This filter is evaluated on three BCI datasets as a proof-of-concept of the method.

  12. Blindness - resources

    Science.gov (United States)

    Resources - blindness ... The following organizations are good resources for information on blindness : American Foundation for the Blind -- www.afb.org Foundation Fighting Blindness -- www.blindness.org National Eye Institute -- ...

  13. Towards Enhanced Underwater Lidar Detection via Source Separation

    Science.gov (United States)

    Illig, David W.

    Interest in underwater optical sensors has grown as technologies enabling autonomous underwater vehicles have been developed. Propagation of light through water is complicated by the dual challenges of absorption and scattering. While absorption can be reduced by operating in the blue-green region of the visible spectrum, reducing scattering is a more significant challenge. Collection of scattered light negatively impacts underwater optical ranging, imaging, and communications applications. This thesis concentrates on the ranging application, where scattering reduces operating range as well as range accuracy. The focus of this thesis is on the problem of backscatter, which can create a "clutter" return that may obscure submerged target(s) of interest. The main contributions of this thesis are explorations of signal processing approaches to increase the separation between the target and backscatter returns. Increasing this separation allows detection of weak targets in the presence of strong scatter, increasing both operating range and range accuracy. Simulation and experimental results will be presented for a variety of approaches as functions of water clarity and target position. This work provides several novel contributions to the underwater lidar field: 1. Quantification of temporal separation approaches: While temporal separation has been studied extensively, this work provides a quantitative assessment of the extent to which both high frequency modulation and spatial filter approaches improve the separation between target and backscatter. 2. Development and assessment of frequency separation: This work includes the first frequency-based separation approach for underwater lidar, in which the channel frequency response is measured with a wideband waveform. Transforming to the time-domain gives a channel impulse response, in which target and backscatter returns may appear in unique range bins and thus be separated. 3. Development and assessment of statistical

  14. Wood ash as a magnesium source for phosphorus recovery from source-separated urine.

    Science.gov (United States)

    Sakthivel, S Ramesh; Tilley, Elizabeth; Udert, Kai M

    2012-03-01

    Struvite precipitation is a simple technology for phosphorus recovery from source-separated urine. However, production costs can be high if expensive magnesium salts are used as precipitants. Therefore, waste products can be interesting alternatives to industrially-produced magnesium salts. We investigated the technical and financial feasibility of wood ash as a magnesium source in India. In batch experiments with source-separated urine, we could precipitate 99% of the phosphate with a magnesium dosage of 2.7 mol Mg mol P(-1). The availability of the magnesium from the wood ash used in our experiment was only about 50% but this could be increased by burning the wood at temperatures well above 600 °C. Depending on the wood ash used, the precipitate can contain high concentrations of heavy metals. This could be problematic if the precipitate were used as fertilizer depending on the applicable fertilizer regulations. The financial study revealed that wood ash is considerably cheaper than industrially-produced magnesium sources and even cheaper than bittern. However, the solid precipitated with wood ash is not pure struvite. Due to the high calcite and the low phosphorus content (3%), the precipitate would be better used as a phosphorus-enhanced conditioner for acidic soils. The estimated fertilizer value of the precipitate was actually slightly lower than wood ash, because 60% of the potassium dissolved into solution during precipitation and was not present in the final product. From a financial point of view and due to the high heavy metal content, wood ash is not a very suitable precipitant for struvite production. Phosphate precipitation from urine with wood ash can be useful if (1) a strong need for a soil conditioner that also contains phosphate exists, (2) potassium is abundant in the soil and (3) no other cheap precipitant, such as bittern or magnesium oxide, is available. PMID:22297249

  15. Residents’ Household Solid Waste (HSW Source Separation Activity: A Case Study of Suzhou, China

    Directory of Open Access Journals (Sweden)

    Hua Zhang

    2014-09-01

    Full Text Available Though the Suzhou government has provided household solid waste (HSW source separation since 2000, the program remains largely ineffective. Between January and March 2014, the authors conducted an intercept survey in five different community groups in Suzhou, and 505 valid surveys were completed. Based on the survey, the authors used an ordered probit regression to study residents’ HSW source separation activities for both Suzhou and for the five community groups. Results showed that 43% of the respondents in Suzhou thought they knew how to source separate HSW, and 29% of them have source separated HSW accurately. The results also found that the current HSW source separation pilot program in Suzhou is valid, as HSW source separation facilities and residents’ separation behavior both became better and better along with the program implementation. The main determinants of residents’ HSW source separation behavior are residents’ age, HSW source separation facilities and government preferential policies. The accessibility to waste management service is particularly important. Attitudes and willingness do not have significant impacts on residents’ HSW source separation behavior.

  16. The Effects of Environmental Management Systems on Source Separation in the Work and Home Settings

    OpenAIRE

    Chris von Borgstede; Maria Andersson; Ola Eriksson

    2012-01-01

    Measures that challenge the generation of waste are needed to address the global problem of the increasing volumes of waste that are generated in both private homes and workplaces. Source separation at the workplace is commonly implemented by environmental management systems (EMS). In the present study, the relationship between source separation at work and at home was investigated. A questionnaire that maps psychological and behavioural predictors of source separation was distributed to empl...

  17. Single-channel source separation using non-negative matrix factorization

    DEFF Research Database (Denmark)

    Schmidt, Mikkel Nørgaard

    , in which a number of methods for single-channel source separation based on non-negative matrix factorization are presented. In the papers, the methods are applied to separating audio signals such as speech and musical instruments and separating different types of tissue in chemical shift imaging....

  18. 30 CFR 57.6404 - Separation of blasting circuits from power source.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Separation of blasting circuits from power... NONMETAL MINES Explosives Electric Blasting-Surface and Underground § 57.6404 Separation of blasting circuits from power source. (a) Switches used to connect the power source to a blasting circuit shall...

  19. 30 CFR 56.6404 - Separation of blasting circuits from power source.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Separation of blasting circuits from power... MINES Explosives Electric Blasting § 56.6404 Separation of blasting circuits from power source. (a) Switches used to connect the power source to a blasting circuit shall be locked in the open position...

  20. A LASER ION-SOURCE FOR ONLINE MASS SEPARATION

    NARCIS (Netherlands)

    VANDUPPEN, P; DENDOOVEN, P; HUYSE, M; VERMEEREN, L; QAMHIEH, ZN; SILVERANS, RE; VANDEWEERT, E

    1992-01-01

    A laser ion source based on resonance photo ionization in a gas cell is proposed. The gas cell, filled with helium, consists of a target chamber in which the recoil products are stopped and neutralized, and an ionization chamber where the atoms of interest are selectively ionized by the laser light.

  1. Procedure for Separating Noise Sources in Measurements of Turbofan Engine Core Noise

    Science.gov (United States)

    Miles, Jeffrey Hilton

    2006-01-01

    The study of core noise from turbofan engines has become more important as noise from other sources like the fan and jet have been reduced. A multiple microphone and acoustic source modeling method to separate correlated and uncorrelated sources has been developed. The auto and cross spectrum in the frequency range below 1000 Hz is fitted with a noise propagation model based on a source couplet consisting of a single incoherent source with a single coherent source or a source triplet consisting of a single incoherent source with two coherent point sources. Examples are presented using data from a Pratt & Whitney PW4098 turbofan engine. The method works well.

  2. Semi-Blind Cancellation of IQ-Imbalances

    OpenAIRE

    Hesse, Matthias; Mailand, Marko; Jentschel, Hans-Joachim; Deneire, Luc; Lebrun, Jerome

    2008-01-01

    The technical realization of modern wireless receivers yields significant interfering IQ-imbalances, which have to be compensated digitally. To cancel these IQ-imbalances, we propose an algorithm using iterative blind source separation (IBSS) as well as information about the modulation scheme used (hence the term semi-blind). The novelty of our approach lies in the fact that we match the nonlinearity involved in the IBSS algorithm to the probability density function of the source signals. Mor...

  3. Quantum Rate Distortion, Reverse Shannon Theorems, and Source-Channel Separation

    OpenAIRE

    Datta, Nilanjana; Hsieh, Min-Hsiu; Wilde, Mark M.

    2013-01-01

    We derive quantum counterparts of two key theorems of classical information theory, namely, the rate distortion theorem and the source-channel separation theorem. The rate-distortion theorem gives the ultimate limits on lossy data compression, and the source-channel separation theorem implies that a two-stage protocol consisting of compression and channel coding is optimal for transmitting a memoryless source over a memoryless channel. In spite of their importance in the classical domain, the...

  4. Student support and perceptions of urine source separation in a university community.

    Science.gov (United States)

    Ishii, Stephanie K L; Boyer, Treavor H

    2016-09-01

    Urine source separation, i.e., the collection and treatment of human urine as a separate waste stream, has the potential to improve many aspects of water resource management and wastewater treatment. However, social considerations must be taken into consideration for successful implementation of this alternative wastewater system. This work evaluated the perceptions of urine source separation held by students living on-campus at a major university in the Southeastern region of the United States. Perceptions were evaluated in the context of the Theory of Planned Behavior. The survey population represents one group within a community type (universities) that is expected to be an excellent testbed for urine source separation. Overall, respondents reported high levels of support for urine source separation after watching a video on expected benefits and risks, e.g., 84% indicated that they would vote in favor of urine source separation in residence halls. Support was less apparent when measured by willingness to pay, as 33% of respondents were unwilling to pay for the implementation of urine source separation and 40% were only willing to pay $1 to $10 per semester. Water conservation was largely identified as the most important benefit of urine source separation and there was little concern reported about the use of urine-based fertilizers. Statistical analyses showed that one's environmental attitude, environmental behavior, perceptions of support within the university community, and belief that student opinions have an impact on university decision makers were significantly correlated with one's support for urine source separation. This work helps identify community characteristics that lend themselves to acceptance of urine source separation, such as those related to environmental attitudes/behaviors and perceptions of behavioral control and subjective norm. Critical aspects of these alternative wastewater systems that require attention in order to foster public

  5. Empirical Study on Factors Influencing Residents' Behavior of Separating Household Wastes at Source

    Institute of Scientific and Technical Information of China (English)

    Qu Ying; Zhu Qinghua; Murray Haight

    2007-01-01

    Source separation is the basic premise for making effective use of household wastes. In eight cities of China, however, several pilot projects of source separation finally failed because of the poor participation rate of residents. In order to solve this problem, identifying those factors that influence residents' behavior of source separation becomes crucial. By means of questionnaire survey, we conducted descriptive analysis and exploratory factor analysis. The results show that trouble-feeling, moral notion, environment protection, public education, environment value and knowledge deficiency are the main factors that play an important role for residents in deciding to separate their household wastes. Also, according to the contribution percentage of the six main factors to the total behavior of source separation, their influencing power is analyzed, which will provide suggestions on household waste management for policy makers and decision makers in China.

  6. Source Separation and Higher-Order Causal Analysis of MEG and EEG

    CERN Document Server

    Zhang, Kun

    2012-01-01

    Separation of the sources and analysis of their connectivity have been an important topic in EEG/MEG analysis. To solve this problem in an automatic manner, we propose a two-layer model, in which the sources are conditionally uncorrelated from each other, but not independent; the dependence is caused by the causality in their time-varying variances (envelopes). The model is identified in two steps. We first propose a new source separation technique which takes into account the autocorrelations (which may be time-varying) and time-varying variances of the sources. The causality in the envelopes is then discovered by exploiting a special kind of multivariate GARCH (generalized autoregressive conditional heteroscedasticity) model. The resulting causal diagram gives the effective connectivity between the separated sources; in our experimental results on MEG data, sources with similar functions are grouped together, with negative influences between groups, and the groups are connected via some interesting sources.

  7. Separation of radiation from two sources from their known radiated sum field

    DEFF Research Database (Denmark)

    Laitinen, Tommi; Pivnenko, Sergey

    2011-01-01

    This paper presents a technique for complete and exact separation of the radiated fields of two sources (at the same frequency) from the knowledge of their radiated sum field. The two sources can be arbitrary but it must be possible to enclose the sources inside their own non-intersecting minimum...

  8. Monaural separation of dependent audio sources based on a generalized Wiener filter

    DEFF Research Database (Denmark)

    Ma, Guilin; Agerkvist, Finn T.; Luther, J.B.

    2007-01-01

    ) coefficients of the dependent sources is modeled by complex Gaussian mixture models in the frequency domain from samples of individual sources to capture the properties of the sources and their correlation. During the second stage, the mixture is separated through a generalized Wiener filter, which takes...

  9. An incentive-based source separation model for sustainable municipal solid waste management in China.

    Science.gov (United States)

    Xu, Wanying; Zhou, Chuanbin; Lan, Yajun; Jin, Jiasheng; Cao, Aixin

    2015-05-01

    Municipal solid waste (MSW) management (MSWM) is most important and challenging in large urban communities. Sound community-based waste management systems normally include waste reduction and material recycling elements, often entailing the separation of recyclable materials by the residents. To increase the efficiency of source separation and recycling, an incentive-based source separation model was designed and this model was tested in 76 households in Guiyang, a city of almost three million people in southwest China. This model embraced the concepts of rewarding households for sorting organic waste, government funds for waste reduction, and introducing small recycling enterprises for promoting source separation. Results show that after one year of operation, the waste reduction rate was 87.3%, and the comprehensive net benefit under the incentive-based source separation model increased by 18.3 CNY tonne(-1) (2.4 Euros tonne(-1)), compared to that under the normal model. The stakeholder analysis (SA) shows that the centralized MSW disposal enterprises had minimum interest and may oppose the start-up of a new recycling system, while small recycling enterprises had a primary interest in promoting the incentive-based source separation model, but they had the least ability to make any change to the current recycling system. The strategies for promoting this incentive-based source separation model are also discussed in this study. PMID:25819930

  10. Bayesian Source Separation Applied to Identifying Complex Organic Molecules in Space

    CERN Document Server

    Knuth, Kevin H; Choinsky, Joshua; Maunu, Haley A; Carbon, Duane F

    2014-01-01

    Emission from a class of benzene-based molecules known as Polycyclic Aromatic Hydrocarbons (PAHs) dominates the infrared spectrum of star-forming regions. The observed emission appears to arise from the combined emission of numerous PAH species, each with its unique spectrum. Linear superposition of the PAH spectra identifies this problem as a source separation problem. It is, however, of a formidable class of source separation problems given that different PAH sources potentially number in the hundreds, even thousands, and there is only one measured spectral signal for a given astrophysical site. Fortunately, the source spectra of the PAHs are known, but the signal is also contaminated by other spectral sources. We describe our ongoing work in developing Bayesian source separation techniques relying on nested sampling in conjunction with an ON/OFF mechanism enabling simultaneous estimation of the probability that a particular PAH species is present and its contribution to the spectrum.

  11. Source Separation and Clustering of Phase-Locked Subspaces: Derivations and Proofs

    OpenAIRE

    Almeida, Miguel; Schleimer, Jan-Hendrik; Bioucas-Dias, José; Vigário, Ricardo

    2011-01-01

    Due to space limitations, our submission "Source Separation and Clustering of Phase-Locked Subspaces", accepted for publication on the IEEE Transactions on Neural Networks in 2011, presented some results without proof. Those proofs are provided in this paper.

  12. Design of Smart Ion-Selective Electrode Arrays Based on Source Separation through Nonlinear Independent Component Analysis

    Directory of Open Access Journals (Sweden)

    Duarte L.T.

    2014-03-01

    Full Text Available The development of chemical sensor arrays based on Blind Source Separation (BSS provides a promising solution to overcome the interference problem associated with Ion-Selective Electrodes (ISE. The main motivation behind this new approach is to ease the time-demanding calibration stage. While the first works on this problem only considered the case in which the ions under analysis have equal valences, the present work aims at developing a BSS technique that works when the ions have different charges. In this situation, the resulting mixing model belongs to a particular class of nonlinear systems that have never been studied in the BSS literature. In order to tackle this sort of mixing process, we adopted a recurrent network as separating system. Moreover, concerning the BSS learning strategy, we develop a mutual information minimization approach based on the notion of the differential of the mutual information. The method works requires a batch operation, and, thus, can be used to perform off-line analysis. The validity of our approach is supported by experiments where the mixing model parameters were extracted from actual data.

  13. Acetaminophen Versus Liquefied Ibuprofen for Control of Pain During Separation in Orthodontic Patients: A Randomized Triple Blinded Clinical Trial.

    Science.gov (United States)

    Hosseinzadeh Nik, Tahereh; Shahsavari, Negin; Ghadirian, Hannaneh; Ostad, Seyed Nasser

    2016-07-01

    The aim of this randomized clinical study was to investigate the effectiveness of acetaminophen 650 mg or liquefied ibuprofen 400 mg in pain control of orthodontic patients during separation with an elastic separator. A total of 101 patients with specific inclusion criteria were divided randomly into three groups (acetaminophen, liquefied ibuprofen, and placebo). They were instructed to take their drugs one hour before separator placement and every six hours afterward (five doses in total). They recorded their discomfort on visual analog scales immediately after separator placement, 2 hours later, 6 hours later, at bedtime, and 24 hours after separator placement. Repeated measure analysis of variance (ANOVA) was used to compare the mean pain scores between the three groups. Data were collected from 89 patients. The pain increased with time in all groups. Pain scores were statistically lower in the analgesic groups compared with the placebo group (P.valueacetaminophen and liquefied ibuprofen) (P.value=1). Acetaminophen and liquefied ibuprofen have similar potential in pain reduction during separation. PMID:27424011

  14. Fate of pharmaceuticals in full-scale source separated sanitation system

    NARCIS (Netherlands)

    Butkovskyi, A.; Hernandez Leal, L.; Rijnaarts, H.H.M.; Zeeman, G.

    2015-01-01

    Removal of 14 pharmaceuticals and 3 of their transformation products was studied in a full-scale source separated sanitation system with separate collection and treatment of black water and grey water. Black water is treated in an up-flow anaerobic sludge blanket (UASB) reactor followed by oxygen

  15. A cost evaluation method for transferring municipalities to solid waste source-separated system.

    Science.gov (United States)

    Lavee, Doron; Nardiya, Shlomit

    2013-05-01

    Most of Israel's waste is disposed in landfills, threatening scarce land resources and posing environmental and health risks. The aim of this study is to estimate the expected costs of transferring municipalities to solid waste source separation in Israel, aimed at reducing the amount of waste directed to landfills and increasing the efficiency and amount of recycled waste. Information on the expected costs of operating a solid waste source separation system was gathered from 47 municipalities and compiled onto a database, taking into consideration various factors such as costs of equipment, construction adjustments and waste collection and disposal. This database may serve as a model for estimating the costs of entering the waste source separation system for any municipality in Israel, while taking into consideration its specific characteristics, such as size and region. The model was used in Israel for determining municipalities' eligibility to receive a governmental grant for entering an accelerated process of solid waste source separation. This study displays a user-friendly and simple operational tool for assessing municipalities' costs of entering a process of waste source separation, providing policy makers a powerful tool for diverting funds effectively in promoting solid waste source separation. PMID:23465315

  16. Prospects of Source-Separation-Based Sanitation Concepts: A Model-Based Study

    Directory of Open Access Journals (Sweden)

    Cees Buisman

    2013-07-01

    Full Text Available Separation of different domestic wastewater streams and targeted on-site treatment for resource recovery has been recognized as one of the most promising sanitation concepts to re-establish the balance in carbon, nutrient and water cycles. In this study a model was developed based on literature data to compare energy and water balance, nutrient recovery, chemical use, effluent quality and land area requirement in four different sanitation concepts: (1 centralized; (2 centralized with source-separation of urine; (3 source-separation of black water, kitchen refuse and grey water; and (4 source-separation of urine, feces, kitchen refuse and grey water. The highest primary energy consumption of 914 MJ/capita(cap/year was attained within the centralized sanitation concept, and the lowest primary energy consumption of 437 MJ/cap/year was attained within source-separation of urine, feces, kitchen refuse and grey water. Grey water bio-flocculation and subsequent grey water sludge co-digestion decreased the primary energy consumption, but was not energetically favorable to couple with grey water effluent reuse. Source-separation of urine improved the energy balance, nutrient recovery and effluent quality, but required larger land area and higher chemical use in the centralized concept.

  17. A Blind Angle? News Sources, Gender and Ethnicity in Danish TV News

    DEFF Research Database (Denmark)

    Fiig, Christina

    The paper will present and discuss a framework for grasping some of the democratic consequences of biased TV news programs. In line with Jürgen Habermas, one can ask what consequences it has for a democratic public sphere that the national TV news landscape is biased in term of source diversity...

  18. A Computational Auditory Scene Analysis-Enhanced Beamforming Approach for Sound Source Separation

    Directory of Open Access Journals (Sweden)

    L. A. Drake

    2009-01-01

    Full Text Available Hearing aid users have difficulty hearing target signals, such as speech, in the presence of competing signals or noise. Most solutions proposed to date enhance or extract target signals from background noise and interference based on either location attributes or source attributes. Location attributes typically involve arrival angles at a microphone array. Source attributes include characteristics that are specific to a signal, such as fundamental frequency, or statistical properties that differentiate signals. This paper describes a novel approach to sound source separation, called computational auditory scene analysis-enhanced beamforming (CASA-EB, that achieves increased separation performance by combining the complementary techniques of CASA (a source attribute technique with beamforming (a location attribute technique, complementary in the sense that they use independent attributes for signal separation. CASA-EB performs sound source separation by temporally and spatially filtering a multichannel input signal, and then grouping the resulting signal components into separated signals, based on source and location attributes. Experimental results show increased signal-to-interference ratio with CASA-EB over beamforming or CASA alone.

  19. What the exercise of the SPICE source inversion validation BlindTest 1 did not tell you

    Science.gov (United States)

    Shao, Guangfu; Ji, Chen

    2012-04-01

    Uncertainties of earthquake finite-fault inversions based upon strong motion data are investigated using the source inversion validation BlindTest 1 exercise of the SPICE (Seismic Wave Propagation and Imaging in Complex Media: A European Network) project, motivated by previous counterintuitive results. The distribution of slip and the shapes of asymmetric slip rate functions are simultaneously inverted by matching 10 or 33 broad-band three-component velocity waveforms within the period ranging from 0.02 to 2 Hz, using a finite-fault method that carries out the waveform inversion in the wavelet domain. The effects of subfault size, data noise and the number of stations have been explored. Our results suggest: (1) Although there are inevitable discrepancies between the inverted model and the target model because of ignoring the spatial slip variations within individual subfaults, the fault slip and rise-time distributions can be well constrained even with the data including large Gaussian noise. (2) It is crucial for source studies to develop new inversion schemes that can properly honour the frequency- and time-dependent energy distribution of seismic radiation and data noise. For instance, inversions using the variance reduction function of velocity waveforms as the objective function have low sensitivities to the total seismic moment and peak slip. (3) Although the relative value of the objective function is guided in the inversion, the absolute value of the objective function cannot be used to evaluate the quality of an inverted model. (4) Because the source inversion is based on surface observations, the spatiotemporal resolution of source inversion is affected not only by the data quality but also by the earthquake itself. For vertical strike-slip faults, the along-strike resolution is better than that along the downdip direction.

  20. Determination of optimal source-detector separation in measuring chromophores in layered tissue with diffuse reflectance

    Institute of Scientific and Technical Information of China (English)

    Yunhan Luo; Houxin Cui; Xiaoyu Gu; Rong Liu; Kexin Xu

    2005-01-01

    Based on analysis of the relation between mean penetration depth and source-detector separation in a threelayer model with the method of Monte-Carlo simulation, an optimal source-detector separation is derived from the mean penetration depth referring to monitoring the change of chromophores concentration of the sandwiched layer. In order to verify the separation, we perform Monte-Carlo simulations with varied absorption coefficient of the sandwiched layer. All these diffuse reflectances are used to construct a calibration model with the method of partial least square (PLS). High correlation coefficients and low root mean square error of prediction (RMSEP) at the optimal separation have confirmed correctness of the selection. This technique is expected to show light on noninvasive diagnosis of near-infrared spectroscopy.

  1. Subband-based Single-channel Source Separation of Instantaneous Audio Mixtures

    OpenAIRE

    Taghia, Jalil; Doostari, Mohammad Ali

    2009-01-01

    In this paper, a new algorithm is developed to separate the audio sources from a single instantaneous mixture. The algorithm is based on subband decomposition and uses a hybrid system of Empirical Mode Decomposition (EMD) and Principle Component Analysis (PCA) to construct artificial observations from the single mixture. In the separation stage of algorithm, we use Independent Component Analysis (ICA) to find independent components. At first the observed mixture is divided into a finite numbe...

  2. Blind convolution speech separation based on multi-band ordering%基于多频段能量相关排序的语音卷积混合盲源分离

    Institute of Scientific and Technical Information of China (English)

    欧旭东; 张天骐; 闫振华; 张世会

    2016-01-01

    针对语音卷积盲源分离频域法排列顺序不确定性问题,提出一种多频段能量排序算法。通过对混合信号的短时傅里叶变换(STFT),在频域上各个频点建立一个瞬时混合模型进行独立分量分析,之后结合能量相关排序法和波达方向(DOA)排序法解决排序不确定性问题,再利用分裂语谱方法解决幅度不确定性问题,进而得到每个频点正确的分离子信号,最后利用逆短时傅里叶(ISTFT)变换得到分离的源信号。仿真结果表明,与Mu-rata的排序算法对比,改进的算法在信号偏差比、信道干扰比、系统误差比上都所提高。%For the ranking uncertainty in frequency domain of speech convolutive blind source separation,this paper deve-loped a new method based on multi-band energy sorting algorithm.Firstly,through the short Fourier transform (STFT)for the mixed signals,it built an instantanneous mixing model in frequency domain of each point and then used independent compo-nent analysis to separate it.After that,it proposed a multi-band energy sorting algorithm which was based on combining ener-gy-related and the direction of arrival (DOA)sorting methods to solve the problem of ranking uncertainty.Then it used the split speech spectral method to solve the problem of the uncertainty of magnitude,and got the proper sub-signals of each fre-quency.Finally,it separated out the source singals through the inverse short Fourier tranform.The simulation experiments show that the proposed method has better source to distortion,source to interference ratio and source to artifacts ratio.

  3. Separation of beam and electrons in the spallation neutron source H- ion source

    International Nuclear Information System (INIS)

    The Spallation Neutron Source (SNS) requires an ion source producing an H- beam with a peak current of 35 mA at a 6.2% duty factor. For the design of this ion source, extracted electrons must be transported and dumped without adversely affecting the H- beam optics. Two issues are considered: (1) electron containment transport and controlled removal; and (2) first-order H- beam steering. For electron containment, various magnetic, geometric and electrode biasing configurations are analyzed. A kinetic description for the negative ions and electrons is employed with self-consistent fields obtained from a steady-state solution to Poisson's equation. Guiding center electron trajectories are used when the gyroradius is sufficiently small. The magnetic fields used to control the transport of the electrons and the asymmetric sheath produced by the gyrating electrons steer the ion beam. Scenarios for correcting this steering by split acceleration and focusing electrodes will be considered in some detail

  4. Separating Turbofan Engine Noise Sources Using Auto and Cross Spectra from Four Microphones

    Science.gov (United States)

    Miles, Jeffrey Hilton

    2008-01-01

    The study of core noise from turbofan engines has become more important as noise from other sources such as the fan and jet were reduced. A multiple-microphone and acoustic-source modeling method to separate correlated and uncorrelated sources is discussed. The auto- and cross spectra in the frequency range below 1000 Hz are fitted with a noise propagation model based on a source couplet consisting of a single incoherent monopole source with a single coherent monopole source or a source triplet consisting of a single incoherent monopole source with two coherent monopole point sources. Examples are presented using data from a Pratt& Whitney PW4098 turbofan engine. The method separates the low-frequency jet noise from the core noise at the nozzle exit. It is shown that at low power settings, the core noise is a major contributor to the noise. Even at higher power settings, it can be more important than jet noise. However, at low frequencies, uncorrelated broadband noise and jet noise become the important factors as the engine power setting is increased.

  5. A Complex Matrix Factorization approach to Joint Modeling of Magnitude and Phase for Source Separation

    OpenAIRE

    Ahuja, Chaitanya; Nathwani, Karan; Rajesh M. Hegde

    2014-01-01

    Conventional NMF methods for source separation factorize the matrix of spectral magnitudes. Spectral Phase is not included in the decomposition process of these methods. However, phase of the speech mixture is generally used in reconstructing the target speech signal. This results in undesired traces of interfering sources in the target signal. In this paper the spectral phase is incorporated in the decomposition process itself. Additionally, the complex matrix factorization problem is reduce...

  6. On-line isotope separation. Tests for targets and ion sources compatibility

    International Nuclear Information System (INIS)

    We have performed a compilation of the influence of various parameters on suitable targets (composition, structure and nuclear constraint) for fission and spallation reactions induced by charged particles. In that case, targets are generally located near or inside the ionization chamber. A survey of typical ions sources and separators particularly used with heavy ion beams is given. These sources are often feeded either by a helium jet transport system or by a catcher foil

  7. Residents’ Preferences for Household Kitchen Waste Source Separation Services in Beijing: A Choice Experiment Approach

    Science.gov (United States)

    Yuan, Yalin; Yabe, Mitsuyasu

    2014-01-01

    A source separation program for household kitchen waste has been in place in Beijing since 2010. However, the participation rate of residents is far from satisfactory. This study was carried out to identify residents’ preferences based on an improved management strategy for household kitchen waste source separation. We determine the preferences of residents in an ad hoc sample, according to their age level, for source separation services and their marginal willingness to accept compensation for the service attributes. We used a multinomial logit model to analyze the data, collected from 394 residents in Haidian and Dongcheng districts of Beijing City through a choice experiment. The results show there are differences of preferences on the services attributes between young, middle, and old age residents. Low compensation is not a major factor to promote young and middle age residents accept the proposed separation services. However, on average, most of them prefer services with frequent, evening, plastic bag attributes and without instructor. This study indicates that there is a potential for local government to improve the current separation services accordingly. PMID:25546279

  8. Residents' preferences for household kitchen waste source separation services in Beijing: a choice experiment approach.

    Science.gov (United States)

    Yuan, Yalin; Yabe, Mitsuyasu

    2014-12-23

    A source separation program for household kitchen waste has been in place in Beijing since 2010. However, the participation rate of residents is far from satisfactory. This study was carried out to identify residents' preferences based on an improved management strategy for household kitchen waste source separation. We determine the preferences of residents in an ad hoc sample, according to their age level, for source separation services and their marginal willingness to accept compensation for the service attributes. We used a multinomial logit model to analyze the data, collected from 394 residents in Haidian and Dongcheng districts of Beijing City through a choice experiment. The results show there are differences of preferences on the services attributes between young, middle, and old age residents. Low compensation is not a major factor to promote young and middle age residents accept the proposed separation services. However, on average, most of them prefer services with frequent, evening, plastic bag attributes and without instructor. This study indicates that there is a potential for local government to improve the current separation services accordingly.

  9. Residents’ Preferences for Household Kitchen Waste Source Separation Services in Beijing: A Choice Experiment Approach

    Directory of Open Access Journals (Sweden)

    Yalin Yuan

    2014-12-01

    Full Text Available A source separation program for household kitchen waste has been in place in Beijing since 2010. However, the participation rate of residents is far from satisfactory. This study was carried out to identify residents’ preferences based on an improved management strategy for household kitchen waste source separation. We determine the preferences of residents in an ad hoc sample, according to their age level, for source separation services and their marginal willingness to accept compensation for the service attributes. We used a multinomial logit model to analyze the data, collected from 394 residents in Haidian and Dongcheng districts of Beijing City through a choice experiment. The results show there are differences of preferences on the services attributes between young, middle, and old age residents. Low compensation is not a major factor to promote young and middle age residents accept the proposed separation services. However, on average, most of them prefer services with frequent, evening, plastic bag attributes and without instructor. This study indicates that there is a potential for local government to improve the current separation services accordingly.

  10. Co-Parenting: Sharing Your Child Equally. A Source Book for the Separated or Divorced Family.

    Science.gov (United States)

    Galper, Miriam

    This source book introduces perspectives and skills which can contribute to successful "co-parenting" (joint custody, joint parenting, co-custody or shared custody) of preadolescent children after parents are separated or divorced. Chapter One introduces the concept of co-parenting. Chapter Two advances an approach to developing flexible…

  11. ENVIRONMENTAL EFFICIENCY, SEPARABILITY AND ABATEMENT COSTS OF NON-POINT SOURCE POLLUTION

    OpenAIRE

    Wossink, Ada; Denaux, Zulal Sogutlu

    2002-01-01

    This paper presents a new framework for analyzing abatement costs of nonpoint-source pollution. Unlike previous studies, this framework treats production and pollution as non-separable and also recognizes that production inefficiency is a fundamental cause of pollution. The implications of this approach are illustrated using an empirical analysis for cotton producers.

  12. Micropollutant removal in an algal treatment system fed with source separated wastewater streams

    NARCIS (Netherlands)

    de Wilt, Arnoud; Butkovskyi, Andrii; Tuantet, Kanjana; Hernandez Leal, Lucia; Fernandes, T.V.; Langenhoff, Alette; Zeeman, Grietje

    2016-01-01

    Micropollutant removal in an algal treatment system fed with source separated wastewater streams was studied. Batch experiments with the microalgae Chlorella sorokiniana grown on urine, anaerobically treated black water and synthetic urine were performed to assess the removal of six spiked pharmaceu

  13. Resource recovery from source separated domestic waste(water) streams; Full scale results

    NARCIS (Netherlands)

    Zeeman, G.; Kujawa, K.

    2011-01-01

    A major fraction of nutrients emitted from households are originally present in only 1% of total wastewater volume. New sanitation concepts enable the recovery and reuse of these nutrients from feces and urine. Two possible sanitation concepts are presented, with varying degree of source separation

  14. Life Cycle Assessment of pretreatment technologies for anaerobic digestion of source-separated organic household waste

    DEFF Research Database (Denmark)

    Naroznova, Irina; Møller, Jacob; Scheutz, Charlotte

    2013-01-01

    The environmental performance of two pretreatment technologies for source-separated organic waste was compared using life cycle assessment (LCA). An innovative pulping process where source-separated organic waste is pulped with cold water forming a volatile solid rich biopulp was compared to a more...... including a number of non-toxic and toxic impact categories were assessed. No big difference in the overall performance of the two technologies was observed. The difference for the separate life cycle steps was, however, more pronounced. More efficient material transfer in the scenario with waste pulping...... resulted in a higher biogas output and nutrient recovery and, thus, the higher impact savings related to biogas production and digest utilization. Meanwhile, larger reject amount in the scenario with screw press led to more savings obtained by utilization of the reject in this scenario....

  15. Static analysis for blinding

    DEFF Research Database (Denmark)

    Nielsen, Christoffer Rosenkilde; Nielson, Hanne Riis

    2006-01-01

    operation blinding. In this paper we study the theoretical foundations for one of the successful approaches to validating cryptographic protocols and we extend it to handle the blinding primitive. Our static analysis approach is based on Flow Logic; this gives us a clean separation between the specification...... of the analysis and its realisation in an automatic tool. We concentrate on the former in the present paper and provide the semantic foundation for our analysis of protocols using blinding - also in the presence of malicious attackers....

  16. Willed blindness

    DEFF Research Database (Denmark)

    Gjerris, Mickey

    2015-01-01

    This article describes how we seem to live in a willed blindness towards the effects that our meat production and consumption have on animals, the environment and the climate. A willed blindness that cannot be explained by either lack of knowledge or scientific uncertainty. The blindness enables us...... willed blindness focusing on the development of either a new moral vision of our obligations or new visions of what a good life is....

  17. Color blindness

    Science.gov (United States)

    ... color blindness often have problems seeing reds and greens, too. The most severe form of color blindness is achromatopsia. This is a rare condition in which a person cannot see any color, only shades of gray. Most color blindness is due to ...

  18. Color Blindness

    Institute of Scientific and Technical Information of China (English)

    严双红

    2007-01-01

    About one in 12 boys is color-blind, and one in every 400 girls, so in each school class there are likely to be at least one or two people who are color-blind. Because they are color- blind from birth, most people do not know that they are color-

  19. Models for the blind

    DEFF Research Database (Denmark)

    Olsén, Jan-Eric

    2014-01-01

    background to the tactile objects of the blind. When did they appear as a specific category of pedagogical aid and how did they help determine the relation between blindness, vision, and touch? Second, I address the tactile objects from the point of view of empirical sources and historical evidence. Material......When displayed in museum cabinets, tactile objects that were once used in the education of blind and visually impaired people, appear to us, sighted visitors, as anything but tactile. We cannot touch them due to museum policies and we can hardly imagine what it would have been like for a blind...... person to touch them in their historical context. And yet these objects are all about touch, from the concrete act of touching something to the norms that assigned touch a specific pedagogical role in nineteenth-century blind schools. The aim of this article is twofold. First, I provide a historical...

  20. Does discharge time source correspond to its geographic source in hydrograph separations? Toward identification of dominant runoff processes in a 300 square kilometer watershed

    Directory of Open Access Journals (Sweden)

    Y. Yokoo

    2014-09-01

    Full Text Available This study compared a time source hydrograph separation method to a geographic source separation method, to assess if the two methods produced similar results. The time source separation of a hydrograph was performed using a numerical filter method and the geographic source separation was performed using an end-member mixing analysis employing hourly discharge, electric conductivity, and turbidity data. These data were collected in 2006 at the Kuroiwa monitoring station on the Abukuma River, Japan. The results of the methods corresponded well in terms of both surface flow components and inter-flow components. In terms of the baseflow component, the result of the time source separation method corresponded with the moving average of the baseflow calculated by the geographic source separation method. These results suggest that the time source separation method is not only able to estimate numerical values for the discharge components, but that the estimates are also reasonable from a geographical viewpoint in the 3000 km2 watershed discussed in this study. The consistent results obtained using the time source and geographic source separation methods demonstrate that it is possible to characterize dominant runoff processes using hourly discharge data, thereby enhancing our capability to interpret the dominant runoff processes of a watershed using observed discharge data alone.

  1. Estimating International Tourism Demand to Spain Separately by the Major Source Markets

    OpenAIRE

    Marcos Alvarez-Díaz; Manuel González-Gómez; Mª Soledad Otero-Giraldez

    2012-01-01

    The objective of this paper is to estimate international tourism demand to Spain separately by major source markets (Germany, United Kingdom, France, Italy and The Netherlands) that represent 67% of the international tourism to Spain. In order to investigate how the tourism demand reacts to price and income changes, we apply the bounds testing approach to cointegration and construct confidence intervals using the bootstrap technique. The results show differences in tourism behavior depending ...

  2. AN IMPROVED FAST BLIND DECONVOLUTION ALGORITHM BASED ON DECORRELATION AND BLOCK MATRIX

    Institute of Scientific and Technical Information of China (English)

    Yang Jun'an; He Xuefan; Tan Ying

    2008-01-01

    In order to alleviate the shortcomings of most blind deconvolution algorithms,this paper proposes an improved fast algorithm for blind deconvolution based on decorrelation technique and broadband block matrix. Althougth the original algorithm can overcome the shortcomings of current blind deconvolution algorithms,it has a constraint that the number of the source signals must be less than that of the channels. The improved algorithm deletes this constraint by using decorrelation technique. Besides,the improved algorithm raises the separation speed in terms of improving the computing methods of the output signal matrix. Simulation results demonstrate the validation and fast separation of the improved algorithm.

  3. Role of the source to building lateral separation distance in petroleum vapor intrusion

    Science.gov (United States)

    Verginelli, Iason; Capobianco, Oriana; Baciocchi, Renato

    2016-06-01

    The adoption of source to building separation distances to screen sites that need further field investigation is becoming a common practice for the evaluation of the vapor intrusion pathway at sites contaminated by petroleum hydrocarbons. Namely, for the source to building vertical distance, the screening criteria for petroleum vapor intrusion have been deeply investigated in the recent literature and fully addressed in the recent guidelines issued by ITRC and U.S.EPA. Conversely, due to the lack of field and modeling studies, the source to building lateral distance received relatively low attention. To address this issue, in this work we present a steady-state vapor intrusion analytical model incorporating a piecewise first-order aerobic biodegradation limited by oxygen availability that accounts for lateral source to building separation. The developed model can be used to evaluate the role and relevance of lateral vapor attenuation as well as to provide a site-specific assessment of the lateral screening distances needed to attenuate vapor concentrations to risk-based values. The simulation outcomes showed to be consistent with field data and 3-D numerical modeling results reported in previous studies and, for shallow sources, with the screening criteria recommended by U.S.EPA for the vertical separation distance. Indeed, although petroleum vapors can cover maximum lateral distances up to 25-30 m, as highlighted by the comparison of model outputs with field evidences of vapor migration in the subsurface, simulation results by this new model indicated that, regardless of the source concentration and depth, 6 m and 7 m lateral distances are sufficient to attenuate petroleum vapors below risk-based values for groundwater and soil sources, respectively. However, for deep sources (> 5 m) and for low to moderate source concentrations (benzene concentrations lower than 5 mg/L in groundwater and 0.5 mg/kg in soil) the above criteria were found extremely conservative as

  4. Sources and speciation of heavy metals in municipal solid waste (MSW) and its effect on the separation technique

    Energy Technology Data Exchange (ETDEWEB)

    Biollaz, S.; Ludwig, Ch.; Stucki, S. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1999-08-01

    A literature search was carried out to determine sources and speciation of heavy metals in MSW. A combination of thermal and mechanical separation techniques is necessary to achieve the required high degrees of metal separation. Metallic goods should be separated mechanically, chemically bound heavy metals by a thermal process. (author) 1 fig., 1 tab., 6 refs.

  5. Source-based neurofeedback methods using EEG recordings: training altered brain activity in a functional brain source derived from blind source separation

    OpenAIRE

    David James White; Marco eCongedo; Joseph eCiorciari

    2014-01-01

    International audience A developing literature explores the use of neurofeedback in the treatment of a range of clinical conditions, particularly ADHD and epilepsy, whilst neurofeedback also provides an experimental tool for studying the functional significance of endogenous brain activity. A critical component of any neurofeedback method is the underlying physiological signal which forms the basis for the feedback. While the past decade has seen the emergence of fMRI-based protocols train...

  6. Carbon Dioxide Capture and Separation Techniques for Gasification-based Power Generation Point Sources

    Energy Technology Data Exchange (ETDEWEB)

    Pennline, H.W.; Luebke, D.R.; Jones, K.L.; Morsi, B.I. (Univ. of Pittsburgh, PA); Heintz, Y.J. (Univ. of Pittsburgh, PA); Ilconich, J.B. (Parsons)

    2007-06-01

    The capture/separation step for carbon dioxide (CO2) from large-point sources is a critical one with respect to the technical feasibility and cost of the overall carbon sequestration scenario. For large-point sources, such as those found in power generation, the carbon dioxide capture techniques being investigated by the in-house research area of the National Energy Technology Laboratory possess the potential for improved efficiency and reduced costs as compared to more conventional technologies. The investigated techniques can have wide applications, but the research has focused on capture/separation of carbon dioxide from flue gas (post-combustion from fossil fuel-fired combustors) and from fuel gas (precombustion, such as integrated gasification combined cycle or IGCC). With respect to fuel gas applications, novel concepts are being developed in wet scrubbing with physical absorption; chemical absorption with solid sorbents; and separation by membranes. In one concept, a wet scrubbing technique is being investigated that uses a physical solvent process to remove CO2 from fuel gas of an IGCC system at elevated temperature and pressure. The need to define an ideal solvent has led to the study of the solubility and mass transfer properties of various solvents. Pertaining to another separation technology, fabrication techniques and mechanistic studies for membranes separating CO2 from the fuel gas produced by coal gasification are also being performed. Membranes that consist of CO2-philic ionic liquids encapsulated into a polymeric substrate have been investigated for permeability and selectivity. Finally, dry, regenerable processes based on sorbents are additional techniques for CO2 capture from fuel gas. An overview of these novel techniques is presented along with a research progress status of technologies related to membranes and physical solvents.

  7. Determination of the source time function of seismic event by blind deconvolution of regional coda wavefield: application to December 22, 2009 explosion at Kambarata, Kyrgyzstan

    Science.gov (United States)

    Sebe, O. G.; Guilbert, J.; Bard, P.

    2011-12-01

    At regional distance, recovering the source time function of a seismic event is a rather difficult task as the Green function is unknown due to large scattering of the waves by crust heterogeneities. Contrary to classical methods based on deterministic assessment of the Green function, this work proposes to exploit the stochastic nature of regional coda wavefield in order to extract the seismic source time function of a regional event. Since the work of Aki and Chouet 1975, it is well recognized that regional coda waves can provide stable and robust information on the source of seismic events. Unfortunately, all the proposed techniques are limited to the power spectral density of the seismic source function. A modified version of our two step spectral factorization algorithm [Sèbe et al. 2005] of coda waves has been proposed in order to include higher order statistic (HOS) blind deconvolution techniques. Assuming that the coda excitation time series is a non-Gaussian independent and identically distributed random signal, the higher order statistics, especially the tricorrelation, is able to remove the randomness of coda excitation and extract source properties. In addition, unlike classical second order approach which only provides the power spectral density, the tricorrelation keeps the information on the phase spectrum of the source, allowing the estimation of the source time function. This original blind deconvolution algorithm of coda waves has been applied on the regional records of the December 22, 2009 explosion in Kambara, Kyrgyzstan. Based on statistic analyses of the higher order cumulants, this method has been able to recover the main properties of the source time function of this detonation: two successive explosions have been identified with a time delay of about 1.7 sec and an amplitude ratio of about 2 in favour of second explosion. This successful blind recovering of high resolution source properties is an encouraging result toward the development

  8. Resonance ionization laser ion sources for on-line isotope separators (invited).

    Science.gov (United States)

    Marsh, B A

    2014-02-01

    A Resonance Ionization Laser Ion Source (RILIS) is today considered an essential component of the majority of Isotope Separator On Line (ISOL) facilities; there are seven laser ion sources currently operational at ISOL facilities worldwide and several more are under development. The ionization mechanism is a highly element selective multi-step resonance photo-absorption process that requires a specifically tailored laser configuration for each chemical element. For some isotopes, isomer selective ionization may even be achieved by exploiting the differences in hyperfine structures of an atomic transition for different nuclear spin states. For many radioactive ion beam experiments, laser resonance ionization is the only means of achieving an acceptable level of beam purity without compromising isotope yield. Furthermore, by performing element selection at the location of the ion source, the propagation of unwanted radioactivity downstream of the target assembly is reduced. Whilst advances in laser technology have improved the performance and reliability of laser ion sources and broadened the range of suitable commercially available laser systems, many recent developments have focused rather on the laser/atom interaction region in the quest for increased selectivity and/or improved spectral resolution. Much of the progress in this area has been achieved by decoupling the laser ionization from competing ionization processes through the use of a laser/atom interaction region that is physically separated from the target chamber. A new application of gas catcher laser ion source technology promises to expand the capabilities of projectile fragmentation facilities through the conversion of otherwise discarded reaction fragments into high-purity low-energy ion beams. A summary of recent RILIS developments and the current status of laser ion sources worldwide is presented.

  9. Resonance ionization laser ion sources for on-line isotope separators (invited)

    International Nuclear Information System (INIS)

    A Resonance Ionization Laser Ion Source (RILIS) is today considered an essential component of the majority of Isotope Separator On Line (ISOL) facilities; there are seven laser ion sources currently operational at ISOL facilities worldwide and several more are under development. The ionization mechanism is a highly element selective multi-step resonance photo-absorption process that requires a specifically tailored laser configuration for each chemical element. For some isotopes, isomer selective ionization may even be achieved by exploiting the differences in hyperfine structures of an atomic transition for different nuclear spin states. For many radioactive ion beam experiments, laser resonance ionization is the only means of achieving an acceptable level of beam purity without compromising isotope yield. Furthermore, by performing element selection at the location of the ion source, the propagation of unwanted radioactivity downstream of the target assembly is reduced. Whilst advances in laser technology have improved the performance and reliability of laser ion sources and broadened the range of suitable commercially available laser systems, many recent developments have focused rather on the laser/atom interaction region in the quest for increased selectivity and/or improved spectral resolution. Much of the progress in this area has been achieved by decoupling the laser ionization from competing ionization processes through the use of a laser/atom interaction region that is physically separated from the target chamber. A new application of gas catcher laser ion source technology promises to expand the capabilities of projectile fragmentation facilities through the conversion of otherwise discarded reaction fragments into high-purity low-energy ion beams. A summary of recent RILIS developments and the current status of laser ion sources worldwide is presented

  10. Detecting changes in respiratory patterns in high frequency chest compression therapy by single-channel blind source separation.

    Science.gov (United States)

    Zhu, Xiaoming; Parhi, Keshab K; Warwick, Warren J

    2009-01-01

    High Frequency Chest Compression (HFCC) is used as a method to remove the mucus in the airway for Cystic Fibrosis (CF) patients. As the characteristics of the tracheal sound reflect the conditions of airways, in this paper, we propose a novel method to evaluate the respiratory patterns in HFCC therapy by using single channel tracheal sounds only. The difficulty of analyzing tracheal sounds lies in that it has a wider frequency band than the air flow at the mouth, and is always corrupted by other biomedical signals and noises. During HFCC therapy, the tracheal sound is also affected by the HFCC machine noise. For this reason, it is difficult to extract respiratory patterns and other related features by traditional filtering techniques. In this paper, we demonstrate use of single-channel independent component analysis to extract respiratory patterns from the tracheal sounds before, during and after HFCC therapy, and use basis features in the tracheal sound to detect the change in respiratory patterns.

  11. Separation of image-distortion sources and magnetic-field measurement in scanning electron microscope (SEM).

    Science.gov (United States)

    Płuska, Mariusz; Czerwinski, Andrzej; Ratajczak, Jacek; Katcki, Jerzy; Oskwarek, Lukasz; Rak, Remigiusz

    2009-01-01

    The electron-microscope image distortion generated by electromagnetic interference (EMI) is an important problem for accurate imaging in scanning electron microscopy (SEM). Available commercial solutions to this problem utilize sophisticated hardware for EMI detection and compensation. Their efficiency depends on the complexity of distortions influence on SEM system. Selection of a proper method for reduction of the distortions is crucial. The current investigations allowed for a separation of the distortions impact on several components of SEM system. A sum of signals from distortion sources causes wavy deformations of specimen shapes in SEM images. The separation of various reasons of the distortion is based on measurements of the periodic deformations of the images for different electron beam energies and working distances between the microscope final aperture and the specimen. Using the SEM images, a direct influence of alternating magnetic field on the electron beam was distinguished. Distortions of electric signals in the scanning block of SEM were also separated. The presented method separates the direct magnetic field influence on the electron beam below the SEM final aperture (in the chamber) from its influence above this aperture (in the electron column). It also allows for the measurement of magnetic field present inside the SEM chamber. The current investigations gave practical guidelines for selecting the most efficient solution for reduction of the distortions.

  12. Rate-constrained source separation for speech enhancement in wireless-communicated binaural hearing aids

    Science.gov (United States)

    Ayllón, David; Gil-Pita, Roberto; Rosa-Zurera, Manuel

    2013-12-01

    A recent trend in hearing aids is the connection of the left and right devices to collaborate between them. Binaural systems can provide natural binaural hearing and support the improvement of speech intelligibility in noise, but they require data transmission between both devices, which increases the power consumption. This paper presents a novel sound source separation algorithm for binaural speech enhancement based on supervised machine learning and time-frequency masking. The system is designed considering the power restrictions in hearing aids, constraining both the computational cost of the algorithm and the transmission bit rate. The transmission schema is optimized using a tailored evolutionary algorithm that assigns a different number of bits to each frequency band. The proposed algorithm requires less than 10% of the available computational resources for signal processing and obtains good separation performance using bit rates lower than 64 kbps.

  13. Strict lower bounds with separation of sources of error in non-overlapping domain decomposition methods

    CERN Document Server

    Rey, Valentine; Rey, Christian

    2016-01-01

    This article deals with the computation of guaranteed lower bounds of the error in the framework of finite element (FE) and domain decomposition (DD) methods. In addition to a fully parallel computation, the proposed lower bounds separate the algebraic error (due to the use of a DD iterative solver) from the discretization error (due to the FE), which enables the steering of the iterative solver by the discretization error. These lower bounds are also used to improve the goal-oriented error estimation in a substructured context. Assessments on 2D static linear mechanic problems illustrate the relevance of the separation of sources of error and the lower bounds' independence from the substructuring. We also steer the iterative solver by an objective of precision on a quantity of interest. This strategy consists in a sequence of solvings and takes advantage of adaptive remeshing and recycling of search directions.

  14. CO2 emission factors for waste incineration: Influence from source separation of recyclable materials

    DEFF Research Database (Denmark)

    Larsen, Anna Warberg; Astrup, Thomas

    2011-01-01

    variations between emission factors for different incinerators, but the background for these variations has not been thoroughly examined. One important reason may be variations in collection of recyclable materials as source separation alters the composition of the residual waste incinerated. The objective...... routed to incineration. Emission factors ranged from 27 to 40kg CO2/GJ. The results appeared most sensitive towards variations in waste composition and water content. Recycling rates and lower heating values could not be used as simple indicators of the resulting emission factors for residual household...

  15. Separation of Radio-Frequency Sources and Localization of Partial Discharges in Noisy Environments

    Directory of Open Access Journals (Sweden)

    Guillermo Robles

    2015-04-01

    Full Text Available The detection of partial discharges (PD can help in early-warning detection systems to protect critical assets in power systems. The radio-frequency emission of these events can be measured with antennas even when the equipment is in service which reduces dramatically the maintenance costs and favours the implementation of condition-based monitoring systems. The drawback of these type of measurements is the difficulty of having a reference signal to study the events in a classical phase-resolved partial discharge pattern (PRPD. Therefore, in open-air substations and overhead lines where interferences from radio and TV broadcasting and mobile communications are important sources of noise and other pulsed interferences from rectifiers or inverters can be present, it is difficult to identify whether there is partial discharges activity or not. This paper proposes a robust method to separate the events captured with the antennas, identify which of them are partial discharges and localize the piece of equipment that is having problems. The separation is done with power ratio (PR maps based on the spectral characteristics of the signal and the identification of the type of event is done localizing the source with an array of four antennas. Several classical methods to calculate the time differences of arrival (TDOA of the emission to the antennas have been tested, and the localization is done using particle swarm optimization (PSO to minimize a distance function.

  16. Nonnegative signal factorization with learnt instrument models for sound source separation in close-microphone recordings

    Science.gov (United States)

    Carabias-Orti, Julio J.; Cobos, Máximo; Vera-Candeas, Pedro; Rodríguez-Serrano, Francisco J.

    2013-12-01

    Close-microphone techniques are extensively employed in many live music recordings, allowing for interference rejection and reducing the amount of reverberation in the resulting instrument tracks. However, despite the use of directional microphones, the recorded tracks are not completely free from source interference, a problem which is commonly known as microphone leakage. While source separation methods are potentially a solution to this problem, few approaches take into account the huge amount of prior information available in this scenario. In fact, besides the special properties of close-microphone tracks, the knowledge on the number and type of instruments making up the mixture can also be successfully exploited for improved separation performance. In this paper, a nonnegative matrix factorization (NMF) method making use of all the above information is proposed. To this end, a set of instrument models are learnt from a training database and incorporated into a multichannel extension of the NMF algorithm. Several options to initialize the algorithm are suggested, exploring their performance in multiple music tracks and comparing the results to other state-of-the-art approaches.

  17. BLIND ADAPTIVE XPIC BASED ON HOS

    Institute of Scientific and Technical Information of China (English)

    Fu Haiyang; Yang Longxiang; Peng Jianglong

    2001-01-01

    This paper presents a new blind XPIC and a new adaptive blind deconvolutional algorithm based on HOS processing, which separates and equalizes the signals in real time. The simulation results demonstrate that the performance of the proposed adaptive blind algorithm,compared with the conventional algorithms, is outstanding with the feature of feasibility, stability and fast convergence rate.

  18. Comparative Ethanol Productivities of Two Different Recombinant Fermenting Strains on Source-Separated Organic Waste

    Directory of Open Access Journals (Sweden)

    Valeriy Bekmuradov

    2014-10-01

    Full Text Available Production of biofuel such as ethanol from lignocellulosic biomass is a beneficial way to meet sustainability and energy security in the future. The main challenge in bioethanol conversion is the high cost of processing, in which enzymatic hydrolysis and fermentation are the major steps. Among the strategies to lower processing costs are utilizing both glucose and xylose sugars present in biomass for conversion. An approach featuring enzymatic hydrolysis and fermentation steps, identified as separate hydrolysis and fermentation (SHF was used in this work. Proposed solution is to use "pre-processing" technologies, including the thermal screw press (TSP and cellulose-organic-solvent based lignocellulose fractionation (COSLIF pretreatments. Such treatments were conducted on a widely available feedstock such as source separated organic waste (SSO to liberate all sugars to be used in the fermentation process. Enzymatic hydrolysis was featured with addition of commercial available enzyme, Accellerase 1500, to mediate enzymatic hydrolysis process. On average, the sugar yield from the TSP and COSLIF pretreatments followed by enzymatic hydrolysis was remarkable at 90%. In this work, evaluation of the SSO hydrolysate obtained from COSLIF and enzymatic hydrolysis pretreaments on ethanol yields was compared by fermentation results with two different recombinant strains: Zymomonas mobilis 8b and Saccharomyces cerevisiae DA2416. At 48 hours of fermentation, ethanol yield was equivalent to 0.48g of ethanol produced per gram of SSO biomass by Z.mobilis 8b and 0.50g of ethanol produced per gram of SSO biomass by S. cerevisiae DA2416. This study provides important insights for investigation of the source-separated organic (SSO waste on ethanol production by different strains and becomes a useful tool to facilitate future process optimization for pilot scale facilities.

  19. Fate of pharmaceuticals in full-scale source separated sanitation system.

    Science.gov (United States)

    Butkovskyi, A; Hernandez Leal, L; Rijnaarts, H H M; Zeeman, G

    2015-11-15

    Removal of 14 pharmaceuticals and 3 of their transformation products was studied in a full-scale source separated sanitation system with separate collection and treatment of black water and grey water. Black water is treated in an up-flow anaerobic sludge blanket (UASB) reactor followed by oxygen-limited autotrophic nitrification-denitrification in a rotating biological contactor and struvite precipitation. Grey water is treated in an aerobic activated sludge process. Concentration of 10 pharmaceuticals and 2 transformation products in black water ranged between low μg/l to low mg/l. Additionally, 5 pharmaceuticals were also present in grey water in low μg/l range. Pharmaceutical influent loads were distributed over two streams, i.e. diclofenac was present for 70% in grey water, while the other compounds were predominantly associated to black water. Removal in the UASB reactor fed with black water exceeded 70% for 9 pharmaceuticals out of the 12 detected, with only two pharmaceuticals removed by sorption to sludge. Ibuprofen and the transformation product of naproxen, desmethylnaproxen, were removed in the rotating biological contactor. In contrast, only paracetamol removal exceeded 90% in the grey water treatment system while removal of other 7 pharmaceuticals was below 40% or even negative. The efficiency of pharmaceutical removal in the source separated sanitation system was compared with removal in the conventional sewage treatment plants. Furthermore, effluent concentrations of black water and grey water treatment systems were compared with predicted no-effect concentrations to assess toxicity of the effluent. Concentrations of diclofenac, ibuprofen and oxazepam in both effluents were higher than predicted no-effect concentrations, indicating the necessity of post-treatment. Ciprofloxacin, metoprolol and propranolol were found in UASB sludge in μg/g range, while pharmaceutical concentrations in struvite did not exceed the detection limits. PMID:26364222

  20. Model-free data analysis for source separation based on Non-Negative Matrix Factorization and k-means clustering (NMFk)

    Science.gov (United States)

    Vesselinov, V. V.; Alexandrov, B.

    2014-12-01

    The identification of the physical sources causing spatial and temporal fluctuations of state variables such as river stage levels and aquifer hydraulic heads is challenging. The fluctuations can be caused by variations in natural and anthropogenic sources such as precipitation events, infiltration, groundwater pumping, barometric pressures, etc. The source identification and separation can be crucial for conceptualization of the hydrological conditions and characterization of system properties. If the original signals that cause the observed state-variable transients can be successfully "unmixed", decoupled physics models may then be applied to analyze the propagation of each signal independently. We propose a new model-free inverse analysis of transient data based on Non-negative Matrix Factorization (NMF) method for Blind Source Separation (BSS) coupled with k-means clustering algorithm, which we call NMFk. NMFk is capable of identifying a set of unique sources from a set of experimentally measured mixed signals, without any information about the sources, their transients, and the physical mechanisms and properties controlling the signal propagation through the system. A classical BSS conundrum is the so-called "cocktail-party" problem where several microphones are recording the sounds in a ballroom (music, conversations, noise, etc.). Each of the microphones is recording a mixture of the sounds. The goal of BSS is to "unmix'" and reconstruct the original sounds from the microphone records. Similarly to the "cocktail-party" problem, our model-freee analysis only requires information about state-variable transients at a number of observation points, m, where m > r, and r is the number of unknown unique sources causing the observed fluctuations. We apply the analysis on a dataset from the Los Alamos National Laboratory (LANL) site. We identify and estimate the impact and sources are barometric pressure and water-supply pumping effects. We also estimate the

  1. Optimization of on-site treatment systems : filtration using geo-textile filters for source separated black wastewater

    OpenAIRE

    Welesameil, Mengstab Tilahun

    2012-01-01

    Filtration performance of three different non-woven geo-textiles (i.e. polypropylene and jute wool) to highly concentrated source separated black wastewater influent was evaluated in laboratory scale, aiming to optimize treatment process as pretreatments.

  2. Separation of the atmospheric variability into non-Gaussian multidimensional sources by projection pursuit techniques

    Science.gov (United States)

    Pires, Carlos A. L.; Ribeiro, Andreia F. S.

    2016-04-01

    We develop an expansion of space-distributed time series into statistically independent uncorrelated subspaces (statistical sources) of low-dimension and exhibiting enhanced non-Gaussian probability distributions with geometrically simple chosen shapes (projection pursuit rationale). The method relies upon a generalization of the principal component analysis that is optimal for Gaussian mixed signals and of the independent component analysis (ICA), optimized to split non-Gaussian scalar sources. The proposed method, supported by information theory concepts and methods, is the independent subspace analysis (ISA) that looks for multi-dimensional, intrinsically synergetic subspaces such as dyads (2D) and triads (3D), not separable by ICA. Basically, we optimize rotated variables maximizing certain nonlinear correlations (contrast functions) coming from the non-Gaussianity of the joint distribution. As a by-product, it provides nonlinear variable changes `unfolding' the subspaces into nearly Gaussian scalars of easier post-processing. Moreover, the new variables still work as nonlinear data exploratory indices of the non-Gaussian variability of the analysed climatic and geophysical fields. The method (ISA, followed by nonlinear unfolding) is tested into three datasets. The first one comes from the Lorenz'63 three-dimensional chaotic model, showing a clear separation into a non-Gaussian dyad plus an independent scalar. The second one is a mixture of propagating waves of random correlated phases in which the emergence of triadic wave resonances imprints a statistical signature in terms of a non-Gaussian non-separable triad. Finally the method is applied to the monthly variability of a high-dimensional quasi-geostrophic (QG) atmospheric model, applied to the Northern Hemispheric winter. We find that quite enhanced non-Gaussian dyads of parabolic shape, perform much better than the unrotated variables in which concerns the separation of the four model's centroid regimes

  3. Instantaneous and Frequency-Warped Signal Processing Techniques for Auditory Source Separation.

    Science.gov (United States)

    Wang, Avery Li-Chun

    This thesis summarizes several contributions to the areas of signal processing and auditory source separation. The philosophy of Frequency-Warped Signal Processing is introduced as a means for separating the AM and FM contributions to the bandwidth of a complex-valued, frequency-varying sinusoid p (n), transforming it into a signal with slowly-varying parameters. This transformation facilitates the removal of p (n) from an additive mixture while minimizing the amount of damage done to other signal components. The average winding rate of a complex-valued phasor is explored as an estimate of the instantaneous frequency. Theorems are provided showing the robustness of this measure. To implement frequency tracking, a Frequency-Locked Loop algorithm is introduced which uses the complex winding error to update its frequency estimate. The input signal is dynamically demodulated and filtered to extract the envelope. This envelope may then be remodulated to reconstruct the target partial, which may be subtracted from the original signal mixture to yield a new, quickly-adapting form of notch filtering. Enhancements to the basic tracker are made which, under certain conditions, attain the Cramer -Rao bound for the instantaneous frequency estimate. To improve tracking, the novel idea of Harmonic -Locked Loop tracking, using N harmonically constrained trackers, is introduced for tracking signals, such as voices and certain musical instruments. The estimated fundamental frequency is computed from a maximum-likelihood weighting of the N tracking estimates, making it highly robust. The result is that harmonic signals, such as voices, can be isolated from complex mixtures in the presence of other spectrally overlapping signals. Additionally, since phase information is preserved, the resynthesized harmonic signals may be removed from the original mixtures with relatively little damage to the residual signal. Finally, a new methodology is given for designing linear-phase FIR filters

  4. Optimizing source detector separation for an implantable perfusion and oxygenation sensor

    Science.gov (United States)

    Akl, T. J.; King, T. J.; Long, R.; Baba, J. S.; McShane, M. J.; Ericson, M. N.; Wilson, M. A.; Coté, G. L.

    2011-03-01

    Each year thousands of patients are added to the waiting list for liver transplants. The first 7-10 days after transplant have proven to be the most critical in patient recovery and it is hypothesized that monitoring organ vital signals in this period can increase patient and graft survival rates. An implantable sensor to monitor the organ perfusion and oxygenation signals following surgery is being developed by our group. The sensor operates based on measuring diffuse reflection from three light emitting diodes (735, 805 and 940 nm). In this work the optimal source detector spacing to maximize oxygenation signal level is investigated for a portal vein model. Monte Carlo simulations provided signal levels and corresponding penetration depths as a function of separation between a point optical source and detector. The modeling results indicated a rapid decay in the optical signal with increasing distance. Through further analysis, it was found that there exists an optimal range of point source to detector spacing, between roughly 1 and 2 mm, in which the blood signal from the simulated portal vein was maximized. Overall, these results are being used to guide the placement and configuration of our probe for in vivo animal studies.

  5. The Doppler Effect based acoustic source separation for a wayside train bearing monitoring system

    Science.gov (United States)

    Zhang, Haibin; Zhang, Shangbin; He, Qingbo; Kong, Fanrang

    2016-01-01

    Wayside acoustic condition monitoring and fault diagnosis for train bearings depend on acquired acoustic signals, which consist of mixed signals from different train bearings with obvious Doppler distortion as well as background noises. This study proposes a novel scheme to overcome the difficulties, especially the multi-source problem in wayside acoustic diagnosis system. In the method, a time-frequency data fusion (TFDF) strategy is applied to weaken the Heisenberg's uncertainty limit for a signal's time-frequency distribution (TFD) of high resolution. Due to the Doppler Effect, the signals from different bearings have different time centers even with the same frequency. A Doppler feature matching search (DFMS) algorithm is then put forward to locate the time centers of different bearings in the TFD spectrogram. With the determined time centers, time-frequency filters (TFF) are designed with thresholds to separate the acoustic signals in the time-frequency domain. Then the inverse STFT (ISTFT) is taken and the signals are recovered and filtered aiming at each sound source. Subsequently, a dynamical resampling method is utilized to remove the Doppler Effect. Finally, accurate diagnosis for train bearing faults can be achieved by applying conventional spectrum analysis techniques to the resampled data. The performance of the proposed method is verified by both simulated and experimental cases. It shows that it is effective to detect and diagnose multiple defective bearings even though they produce multi-source acoustic signals.

  6. Models for the Blind

    Directory of Open Access Journals (Sweden)

    Jan Eric Olsén

    2014-10-01

    Full Text Available When displayed in museum cabinets, tactile objects that were once used in the education of blind and visually impaired people, appear to us, sighted visitors, as anything but tactile. We cannot touch them due to museum policies and we can hardly imagine what it would have been like for a blind person to touch them in their historical context. And yet these objects are all about touch, from the concrete act of touching something to the norms that assigned touch a specific pedagogical role in nineteenth-century blind schools. The aim of this article is twofold. First, I provide a historical background to the tactile objects of the blind. When did they appear as a specific category of pedagogical aid and how did they help determine the relation between blindness, vision, and touch? Second, I address the tactile objects from the point of view of empirical sources and historical evidence. Material objects are rarely used as historical testimonies for the simple reason that they, unlike archival material, do not present historians with written documents that can be held as evidence of the past. However, as I point out, certain historical questions of which archives remain silent could be approached by other means such as the use of material objects. Rather than delivering concrete methodological suggestions, this second part reflects upon the historical use of material objects - both their possibilities and their limits - within the context of blindness.

  7. Performance of a ruthenium beam separator used to separate soft x rays from light generated by a high-order harmonic light source.

    Science.gov (United States)

    Ichimaru, Satoshi; Hatayama, Masatoshi; Ohchi, Tadayuki; Gullikson, Eric M; Oku, Satoshi

    2016-02-10

    We describe the design and fabrication of a ruthenium beam separator used to simultaneously attenuate infrared light and reflect soft x rays. Measurements in the infrared and soft x-ray regions showed the beam separator to have a reflectivity of 50%-85% in the wavelength region from 6 to 10 nm at a grazing incidence angle of 7.5 deg and 4.3% at 800 nm and the same angle of grazing incidence, indicating that the amount of attenuation is 0.05-0.09. These results show that this beam separator could provide an effective means for separating IR light from soft x rays in light generated by high-order harmonic generation sources. PMID:26906363

  8. A system dynamics model to evaluate effects of source separation of municipal solid waste management: A case of Bangkok, Thailand.

    Science.gov (United States)

    Sukholthaman, Pitchayanin; Sharp, Alice

    2016-06-01

    Municipal solid waste has been considered as one of the most immediate and serious problems confronting urban government in most developing and transitional economies. Providing solid waste performance highly depends on the effectiveness of waste collection and transportation process. Generally, this process involves a large amount of expenditures and has very complex and dynamic operational problems. Source separation has a major impact on effectiveness of waste management system as it causes significant changes in quantity and quality of waste reaching final disposal. To evaluate the impact of effective source separation on waste collection and transportation, this study adopts a decision support tool to comprehend cause-and-effect interactions of different variables in waste management system. A system dynamics model that envisages the relationships of source separation and effectiveness of waste management in Bangkok, Thailand is presented. Influential factors that affect waste separation attitudes are addressed; and the result of change in perception on waste separation is explained. The impacts of different separation rates on effectiveness of provided collection service are compared in six scenarios. 'Scenario 5' gives the most promising opportunities as 40% of residents are willing to conduct organic and recyclable waste separation. The results show that better service of waste collection and transportation, less monthly expense, extended landfill life, and satisfactory efficiency of the provided service at 60.48% will be achieved at the end of the simulation period. Implications of how to get public involved and conducted source separation are proposed. PMID:27026497

  9. Two-microphone Separation of Speech Mixtures

    DEFF Research Database (Denmark)

    2006-01-01

    of Speech Mixtures," 2006, submited for journal publication. See also, [2] Michael Syskind Pedersen, DeLiang Wang, Jan Larsen and Ulrik Kjems: "Overcomplete Blind Source Separation by Combining ICA and Binary Time-Frequency Masking," in proceedings of IEEE International workshop on Machine Learning...

  10. Non-contact time-resolved diffuse reflectance imaging at null source-detector separation.

    Science.gov (United States)

    Mazurenka, M; Jelzow, A; Wabnitz, H; Contini, D; Spinelli, L; Pifferi, A; Cubeddu, R; Mora, A Dalla; Tosi, A; Zappa, F; Macdonald, R

    2012-01-01

    We report results of the proof-of-principle tests of a novel non-contact tissue imaging system. The system utilizes a quasi-null source-detector separation approach for time-domain near-infrared spectroscopy, taking advantage of an innovative state-of-the-art fast-gated single photon counting detector. Measurements on phantoms demonstrate the feasibility of the non-contact approach for the detection of optically absorbing perturbations buried up to a few centimeters beneath the surface of a tissue-like turbid medium. The measured depth sensitivity and spatial resolution of the new system are close to the values predicted by Monte Carlo simulations for the inhomogeneous medium and an ideal fast-gated detector, thus proving the feasibility of the non-contact approach for high density diffuse reflectance measurements on tissue. Potential applications of the system are also discussed. PMID:22274351

  11. Designing of a lead ion model source for plasma separation of spent nuclear fuel

    Science.gov (United States)

    Antonov, N. N.; Vorona, N. A.; Gavrikov, A. V.; Samokhin, A. A.; Smirnov, V. P.

    2016-02-01

    Plasma sources of model substances are required for solving problems associated with the development of a plasma separation method for spent nuclear fuel (SNF). Lead is chosen as the substance simulating the kinetics and dynamics of the heavy SNF component. We report on the results of analysis of the discharge in lead vapor with a concentration of 1012-1013 cm-3. Ionization is produced by an electron beam (with electron energy up to 500 eV) in the centimeter gap between planar electrodes. The discharge is simulated using the hydrodynamic and one-particle approximations. The current-voltage characteristics and efficiencies of single ionization depending on the vapor concentrations and thermoelectron current are obtained. The experimentally determined ion currents on the order of 100 μA for an ionization efficiency on the order of 0.1% are in conformity with the result of simulation.

  12. Saline sewage treatment and source separation of urine for more sustainable urban water management.

    Science.gov (United States)

    Ekama, G A; Wilsenach, J A; Chen, G H

    2011-01-01

    While energy consumption and its associated carbon emission should be minimized in wastewater treatment, it has a much lower priority than human and environmental health, which are both closely related to efficient water quality management. So conservation of surface water quality and quantity are more important for sustainable development than green house gas (GHG) emissions per se. In this paper, two urban water management strategies to conserve fresh water quality and quantity are considered: (1) source separation of urine for improved water quality and (2) saline (e.g. sea) water toilet flushing for reduced fresh water consumption in coastal and mining cities. The former holds promise for simpler and shorter sludge age activated sludge wastewater treatment plants (no nitrification and denitrification), nutrient (Mg, K, P) recovery and improved effluent quality (reduced endocrine disruptor and environmental oestrogen concentrations) and the latter for significantly reduced fresh water consumption, sludge production and oxygen demand (through using anaerobic bioprocesses) and hence energy consumption. Combining source separation of urine and saline water toilet flushing can reduce sewer crown corrosion and reduce effluent P concentrations. To realize the advantages of these two approaches will require significant urban water management changes in that both need dual (fresh and saline) water distribution and (yellow and grey/brown) wastewater collection systems. While considerable work is still required to evaluate these new approaches and quantify their advantages and disadvantages, it would appear that the investment for dual water distribution and wastewater collection systems may be worth making to unlock their benefits for more sustainable urban development. PMID:22214085

  13. Iterative algorithm on single-channel blind separation and decoding of co-frequency modulated signals%基于迭代的同频混合信号单通道盲分离/译码算法

    Institute of Scientific and Technical Information of China (English)

    廖灿辉; 涂世龙; 万坚

    2011-01-01

    针对采用长约束信道编码的同频调制混合信号,提出了一种利用编码的单通道盲分离/译码迭代算法.该算法通过在盲分离过程中利用译码后反馈的符号软信息来改善分离效果,重点研究了软输入软输出盲分离、最大似然概率译码以及分离译码间的软信息交互.仿真结果表明,迭代盲分离算法相比不采用迭代的算法可获得更好的性能,对于采用(2,1,6)卷积码和随机交织的BPSK混合信号,前者进行2次迭代时可获得约2dB的信噪比增益.%An algorithm was proposed to exploit the codes in iterative single-channel blind separation and decoding of two co-frequency modulated signals with long-constraint channel codes. The output log-likelihood ratio (LLR) values of the decoder were used as a prior LLR fed back to the separator to improve the separation performance. Special emphases were laid on soft input soft output blind separation, maximum a posteriori (MAP) decoding and LLR interaction between separator and decoder. Simulation results show that the proposed algorithm can make a significant improvement in performance over the algorithms without iterations. For BPSK signals with (2,1,6) convolutional codes and random interleaving, a gain of about 2dB in signal-noise ratio can be obtained after two iterations.

  14. The Crowding-Out Effects of Garbage Fees and Voluntary Source Separation Programs on Waste Reduction: Evidence from China

    Directory of Open Access Journals (Sweden)

    Hongyun Han

    2016-07-01

    Full Text Available This paper examines how and to what degree government policies of garbage fees and voluntary source separation programs, with free indoor containers and garbage bags, can affect the effectiveness of municipal solid waste (MSW management, in the sense of achieving a desirable reduction of per capita MSW generation. Based on city-level panel data for years 1998–2012 in China, our empirical analysis indicates that per capita MSW generated is increasing with per capita disposable income, average household size, education levels of households, and the lagged per capita MSW. While both garbage fees and source separation programs have separately led to reductions in per capita waste generation, the interaction of the two policies has resulted in an increase in per capita waste generation due to the following crowding-out effects: Firstly, the positive effect of income dominates the negative effect of the garbage fee. Secondly, there are crowding-out effects of mandatory charging system and the subsidized voluntary source separation on per capita MSW generation. Thirdly, small subsidies and tax punishments have reduced the intrinsic motivation for voluntary source separation of MSW. Thus, compatible fee charging system, higher levels of subsidies, and well-designed public information and education campaigns are required to promote household waste source separation and reduction.

  15. Effect of source-separated urine storage on estrogenic activity detected using bioluminescent yeast Saccharomyces cerevisiae.

    Science.gov (United States)

    Jaatinen, Sanna; Kivistö, Anniina; Palmroth, Marja R T; Karp, Matti

    2016-09-01

    The objective was to demonstrate that a microbial whole cell biosensor, bioluminescent yeast, Saccharomyces cerevisiae (BMAEREluc/ERα) can be applied to detect overall estrogenic activity from fresh and stored human urine. The use of source-separated urine in agriculture removes a human originated estrogen source from wastewater influents, subsequently enabling nutrient recycling. Estrogenic activity in urine should be diminished prior to urine usage in agriculture in order to prevent its migration to soil. A storage period of 6 months is required for hygienic reasons; therefore, estrogenic activity monitoring is of interest. The method measured cumulative female hormone-like activity. Calibration curves were prepared for estrone, 17β-estradiol, 17α- ethinylestradiol and estriol. Estrogen concentrations of 0.29-29,640 μg L(-1) were detectable while limit of detection corresponded to 0.28-35 μg L(-1) of estrogens. The yeast sensor responded well to fresh and stored urine and gave high signals corresponding to 0.38-3,804 μg L(-1) of estrogens in different urine samples. Estrogenic activity decreased during storage, but was still higher than in fresh urine implying insufficient storage length. The biosensor was suitable for monitoring hormonal activity in urine and can be used in screening anthropogenic estrogen-like compounds interacting with the receptor.

  16. Effect of source-separated urine storage on estrogenic activity detected using bioluminescent yeast Saccharomyces cerevisiae.

    Science.gov (United States)

    Jaatinen, Sanna; Kivistö, Anniina; Palmroth, Marja R T; Karp, Matti

    2016-09-01

    The objective was to demonstrate that a microbial whole cell biosensor, bioluminescent yeast, Saccharomyces cerevisiae (BMAEREluc/ERα) can be applied to detect overall estrogenic activity from fresh and stored human urine. The use of source-separated urine in agriculture removes a human originated estrogen source from wastewater influents, subsequently enabling nutrient recycling. Estrogenic activity in urine should be diminished prior to urine usage in agriculture in order to prevent its migration to soil. A storage period of 6 months is required for hygienic reasons; therefore, estrogenic activity monitoring is of interest. The method measured cumulative female hormone-like activity. Calibration curves were prepared for estrone, 17β-estradiol, 17α- ethinylestradiol and estriol. Estrogen concentrations of 0.29-29,640 μg L(-1) were detectable while limit of detection corresponded to 0.28-35 μg L(-1) of estrogens. The yeast sensor responded well to fresh and stored urine and gave high signals corresponding to 0.38-3,804 μg L(-1) of estrogens in different urine samples. Estrogenic activity decreased during storage, but was still higher than in fresh urine implying insufficient storage length. The biosensor was suitable for monitoring hormonal activity in urine and can be used in screening anthropogenic estrogen-like compounds interacting with the receptor. PMID:26804108

  17. The source regions of solar energetic particles detected by widely separated spacecraft

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jinhye; Moon, Y.-J. [School of Space Research, Kyung Hee University, Yongin 446-701 (Korea, Republic of); Innes, D. E.; Bucik, R., E-mail: jinhye@khu.ac.kr [Max Planck Institute for Solar System Research, D-37191 Katlenburg-Lindau (Germany)

    2013-12-20

    We studied the source regions of 12 solar energetic particle (SEP) events seen between 2010 August and 2012 January at STEREO-A, B, and/or Earth (Advanced Composition Explorer/Solar and Heliospheric Observatory/GOES), when the two STEREO spacecraft were separated by about 180°. All events were associated with flares (C1 to X6) and fast coronal mass ejections and, except for one, accompanied by type II radio bursts. We have determined the arrival times of the SEPs at the three positions. Extreme ultraviolet (EUV) waves, observed in the 195 Å and 193 Å channels of STEREO and the Solar Dynamics Observatory, are tracked across the Sun to determine their arrival time at the photospheric source of open field lines connecting to the spacecraft. There is a good correlation between the EUV wave arrival times at the connecting footpoints and the SEP onset times. The delay time between electron onset and the EUV wave reaching the connecting footpoint is independent of distance from the flare site. The proton delay time increases with distance from the flare site. In three of the events, secondary flare sites may have also contributed to the wide longitudinal spread of SEPs.

  18. Blind Friendly Maps

    OpenAIRE

    Červenka, Petr; Břinda, Karel; Seifert, Radek; Hofman, Petr

    2016-01-01

    Space concept of the surrounding area is one of the most important preconditions of the independent mobility and orientation of the blind people. Tactile maps are considered to be the most appropriate source of spatial information. One of the main problems of the tactile maps usage is their problematic accessibility for the blind users since they are not available in time and with up-to-date content. The map production is a matter of tedious manual work and a result of expensive and time-cons...

  19. Informed Source Separation of Atmospheric and Surface Signal Contributions in Shortwave Hyperspectral Imagery using Non-negative Matrix Factorization

    Science.gov (United States)

    Wright, L.; Coddington, O.; Pilewskie, P.

    2015-12-01

    Current challenges in Earth remote sensing require improved instrument spectral resolution, spectral coverage, and radiometric accuracy. Hyperspectral instruments, deployed on both aircraft and spacecraft, are a growing class of Earth observing sensors designed to meet these challenges. They collect large amounts of spectral data, allowing thorough characterization of both atmospheric and surface properties. The higher accuracy and increased spectral and spatial resolutions of new imagers require new numerical approaches for processing imagery and separating surface and atmospheric signals. One potential approach is source separation, which allows us to determine the underlying physical causes of observed changes. Improved signal separation will allow hyperspectral instruments to better address key science questions relevant to climate change, including land-use changes, trends in clouds and atmospheric water vapor, and aerosol characteristics. In this work, we investigate a Non-negative Matrix Factorization (NMF) method for the separation of atmospheric and land surface signal sources. NMF offers marked benefits over other commonly employed techniques, including non-negativity, which avoids physically impossible results, and adaptability, which allows the method to be tailored to hyperspectral source separation. We adapt our NMF algorithm to distinguish between contributions from different physically distinct sources by introducing constraints on spectral and spatial variability and by using library spectra to inform separation. We evaluate our NMF algorithm with simulated hyperspectral images as well as hyperspectral imagery from several instruments including, the NASA Airborne Visible/Infrared Imaging Spectrometer (AVIRIS), NASA Hyperspectral Imager for the Coastal Ocean (HICO) and National Ecological Observatory Network (NEON) Imaging Spectrometer.

  20. High acceptance of urine source separation in seven European countries: a review.

    Science.gov (United States)

    Lienert, Judit; Larsen, Tove A

    2010-01-15

    Urine source separation (NoMix-technology) is a promising innovation aiming at a resource-oriented, decentralized approach in urban water management. However, NoMix-technology has a sensitive end-point: people's bathrooms. NoMix-technology is increasingly applied in European pilot projects, but the success from a user point-of-view has rarely been systematically monitored. We aim at closing this gap. We review surveys on acceptance, including reuse of human urine as fertilizer, from 38 NoMix-projects in 7 Northern and Central European countries with 2700 respondents. Additionally, we identify explanatory variables with logistic regression of a representative Swiss library survey. NoMix-technology is well accepted; around 80% of users liked the idea, 75-85% were satisfied with design, hygiene, smell, and seating comfort of NoMix-toilets, 85% regarded urine-fertilizers as good idea (50% of farmers), and 70% would purchase such food. However, 60% of users encountered problems; NoMix-toilets need further development. We found few differences among countries, but systematic differences between public and private settings, where people seem more critical. Information was positively correlated with acceptance, and, e.g., a good mood or environmentally friendly behavior. For future success of NoMix-projects, we recommend authorities follow an integral strategy. Lay people will then find the NoMix-concept appealing and support this promising bathroom innovation. PMID:20000706

  1. Liquid digestate from anaerobic treatment of source-separated household waste as fertilizer to barley.

    Science.gov (United States)

    Haraldsen, Trond Knapp; Andersen, Uno; Krogstad, Tore; Sørheim, Roald

    2011-12-01

    This study examined the efficiency of different organic waste materials as NPK fertilizer, in addition to the risk for leaching losses related to shower precipitation in the first part of the growing season. The experiment was tested in a pot trial on a sandy soil in a greenhouse. Six organic fertilizers were evaluated: liquid anaerobic digestate (LAD) sourced from separated household waste, nitrified liquid anaerobic digestate (NLAD) of the same origin as LAD, meat and bone meal (MBM), hydrolysed salmon protein (HSP), reactor-composted catering waste (CW) and cattle manure (CM). An unfertilized control, calcium nitrate (CN) and Fullgjødsel® 21-4-10 were used as reference fertilizers. At equal amounts of mineral nitrogen both LAD and Fullgjødsel® gave equal yield of barley in addition to equal uptake of N, P, and K in barley grain. NLAD gave significantly lower barley yield than the original LAD due to leaching of nitrate-N after a simulated surplus of precipitation (28 mm) at Zadoks 14. There was significantly increased leaching of nitrate N from the treatments receiving 160 kg N ha(-1) of CN and NLAD in comparison with all the other organic fertilizers. In this study LAD performed to the same degree as Fullgjødsel® NPK fertilizer and it was concluded that LAD can be recommended as fertilizer for cereals. Nitrification of the ammonium N in the digestate caused significantly increased nitrate leaching, and cannot be recommended.

  2. Insects associated with the composting process of solid urban waste separated at the source

    Directory of Open Access Journals (Sweden)

    Gladis Estela Morales

    2010-01-01

    Full Text Available Sarcosaprophagous macroinvertebrates (earthworms, termites and a number of Diptera larvae enhance changes in the physical and chemical properties of organic matter during degradation and stabilization processes in composting, causing a decrease in the molecular weights of compounds. This activity makes these organisms excellent recyclers of organic matter. This article evaluates the succession of insects associated with the decomposition of solid urban waste separated at the source. The study was carried out in the city of Medellin, Colombia. A total of 11,732 individuals were determined, belonging to the classes Insecta and Arachnida. Species of three orders of Insecta were identified, Diptera, Coleoptera and Hymenoptera. Diptera corresponding to 98.5% of the total, was the most abundant and diverse group, with 16 families (Calliphoridae, Drosophilidae, Psychodidae, Fanniidae, Muscidae, Milichiidae, Ulidiidae, Scatopsidae, Sepsidae, Sphaeroceridae, Heleomyzidae, Stratiomyidae, Syrphidae, Phoridae, Tephritidae and Curtonotidae followed by Coleoptera with five families (Carabidae, Staphylinidae, Ptiliidae, Hydrophilidae and Phalacaridae. Three stages were observed during the composting process, allowing species associated with each stage to be identified. Other species were also present throughout the whole process. In terms of number of species, Diptera was the most important group observed, particularly Ornidia obesa, considered a highly invasive species, and Hermetia illuscens, both reported as beneficial for decomposition of organic matter.

  3. Energy and time modelling of kerbside waste collection: Changes incurred when adding source separated food waste.

    Science.gov (United States)

    Edwards, Joel; Othman, Maazuza; Burn, Stewart; Crossin, Enda

    2016-10-01

    The collection of source separated kerbside municipal FW (SSFW) is being incentivised in Australia, however such a collection is likely to increase the fuel and time a collection truck fleet requires. Therefore, waste managers need to determine whether the incentives outweigh the cost. With literature scarcely describing the magnitude of increase, and local parameters playing a crucial role in accurately modelling kerbside collection; this paper develops a new general mathematical model that predicts the energy and time requirements of a collection regime whilst incorporating the unique variables of different jurisdictions. The model, Municipal solid waste collect (MSW-Collect), is validated and shown to be more accurate at predicting fuel consumption and trucks required than other common collection models. When predicting changes incurred for five different SSFW collection scenarios, results show that SSFW scenarios require an increase in fuel ranging from 1.38% to 57.59%. There is also a need for additional trucks across most SSFW scenarios tested. All SSFW scenarios are ranked and analysed in regards to fuel consumption; sensitivity analysis is conducted to test key assumptions.

  4. The management challenge for household waste in emerging economies like Brazil: realistic source separation and activation of reverse logistics.

    Science.gov (United States)

    Fehr, M

    2014-09-01

    Business opportunities in the household waste sector in emerging economies still evolve around the activities of bulk collection and tipping with an open material balance. This research, conducted in Brazil, pursued the objective of shifting opportunities from tipping to reverse logistics in order to close the balance. To do this, it illustrated how specific knowledge of sorted waste composition and reverse logistics operations can be used to determine realistic temporal and quantitative landfill diversion targets in an emerging economy context. Experimentation constructed and confirmed the recycling trilogy that consists of source separation, collection infrastructure and reverse logistics. The study on source separation demonstrated the vital difference between raw and sorted waste compositions. Raw waste contained 70% biodegradable and 30% inert matter. Source separation produced 47% biodegradable, 20% inert and 33% mixed material. The study on collection infrastructure developed the necessary receiving facilities. The study on reverse logistics identified private operators capable of collecting and processing all separated inert items. Recycling activities for biodegradable material were scarce and erratic. Only farmers would take the material as animal feed. No composting initiatives existed. The management challenge was identified as stimulating these activities in order to complete the trilogy and divert the 47% source-separated biodegradable discards from the landfills.

  5. Two-microphone Separation of Speech Mixtures

    DEFF Research Database (Denmark)

    2006-01-01

    Matlab source code for underdetermined separation of instaneous speech mixtures. The algorithm is described in [1] Michael Syskind Pedersen, DeLiang Wang, Jan Larsen and Ulrik Kjems: ''Two-microphone Separation of Speech Mixtures,'' 2006, submitted for journal publoication. See also, [2] Michael...... Syskind Pedersen, DeLiang Wang, Jan Larsen and Ulrik Kjems: ''Overcomplete Blind Source Separation by Combining ICA and Binary Time-Frequency Masking,'' in proceedings of IEEE International workshop on Machine Learning for Signal Processing, pp. 15-20, 2005. All files should be in the same directory...

  6. Deep Transform: Cocktail Party Source Separation via Probabilistic Re-Synthesis

    OpenAIRE

    Simpson, Andrew J. R.

    2015-01-01

    In cocktail party listening scenarios, the human brain is able to separate competing speech signals. However, the signal processing implemented by the brain to perform cocktail party listening is not well understood. Here, we trained two separate convolutive autoencoder deep neural networks (DNN) to separate monaural and binaural mixtures of two concurrent speech streams. We then used these DNNs as convolutive deep transform (CDT) devices to perform probabilistic re-synthesis. The CDTs operat...

  7. A HOS-based Blind Signal Extraction Method for Chaotic MIMO Systems

    Institute of Scientific and Technical Information of China (English)

    GONG Yun-rui; HE Di; HE Chen; JIANG Ling-ge

    2008-01-01

    A novel method to extract multiple input and multiple output (MIMO) chaotic signals was pro-posed using the blind neural algorithm after transmitting in nonideal channel. The MIMO scheme with different chaotic signal generators was presented. In order to separate the chaotic source signals only by using the sensor signals at receivers, a blind neural extraction algorithm based on higher-order statistic (HOS) technique was used to recover the primary chaotic signals. Simulation results show that the proposed approach has good performance in separating the primary chaotic signals even under nonideal channel.

  8. Normalization and source separation of acoustic emission signals for condition monitoring and fault detection of multi-cylinder diesel engines

    Science.gov (United States)

    Wu, Weiliang; Lin, Tian Ran; Tan, Andy C. C.

    2015-12-01

    A signal processing technique is presented in this paper to normalize and separate the source of non-linear acoustic emission (AE) signals of a multi-cylinder diesel engine for condition monitoring applications and fault detection. The normalization technique presented in the paper overcomes the long-existing non-linearity problem of AE sensors so that responses measured by different AE sensors can be quantitatively analysed and compared. A source separation algorithm is also developed in the paper to separate the mixture of the normalized AE signals produced by a multi-cylinder diesel engine by utilising the system parameters (i.e., wave attenuation constant and the arrival time delay) of AE wave propagation determined by a standard pencil lead break test on the engine cylinder head. It is shown that the source separation algorithm is able to separate the signal interference of adjacent cylinders from the monitored cylinder once the wave attenuation constant and the arrival time delay along the propagation path are known. The algorithm is particularly useful in the application of AE technique for condition monitoring of small-size diesel engines where signal interference from the neighbouring cylinders is strong.

  9. Chemical characteristics and methane potentials of source-separated and pre-treated organic municipal solid waste

    DEFF Research Database (Denmark)

    Hansen, Trine Lund; Svärd, Å; Angelidaki, Irini;

    2003-01-01

    A research project has investigated the biogas potential of pre-screened source-separated organic waste. Wastes from five Danish cities have been pre-treated by three methods: screw press; disc screen; and shredder and magnet. This paper outlines the sampling procedure used, the chemical...... composition of the wastes and the estimated methane potentials....

  10. Anaerobic treatment as a core technology for energy, nutrients and water from source-separated domestic waste(water)

    NARCIS (Netherlands)

    Zeeman, G.; Kujawa, K.; Mes, de T.Z.D.; Graaff, de M.S.; Abu-Ghunmi, L.N.A.H.; Mels, A.R.; Meulman, B.; Temmink, B.G.; Buisman, C.J.N.; Lier, van J.B.; Lettinga, G.

    2008-01-01

    Based on results of pilot scale research with source-separated black water (BW) and grey water (GW), a new sanitation concept is proposed. BW and GW are both treated in a UASB (-septic tank) for recovery of CH4 gas. Kitchen waste is added to the anaerobic BW treatment for doubling the biogas product

  11. Blind channel identication of nonlinear folding mixing model

    Institute of Scientific and Technical Information of China (English)

    Su Yong; Xu Shangzhi; Ye Zhongfu

    2006-01-01

    Signals from multi-sensor systems are often mixtures of (statistically) independent sources by unknown mixing method. Blind source separation(BSS) and independent component analysis(ICA) are the methods to identify/recover the channels and the sources. BSS/ICA of nonlinear mixing models are difficult problems. For instance, the post-nonlinear model has been studied by several authors. It is noticed that in most cases, the proposed models are always with an invertible mixing. According to this fact there is an interesting question: how about the situation of the non-invertible non-linear mixing in BSS or ICA? A new simple non-linear mixing model is proposed with a kind of non-invertible mixing, the folding mixing, and method to identify its channel, blindly.

  12. Feedback Control and Dynamic Behaviour of Z-Source Converter Fed Separately Excited DC Motor and Centrifugal Pump Set

    Directory of Open Access Journals (Sweden)

    Saswati Swapna Dash

    2014-07-01

    Full Text Available This paper presents an overall study of Feedback Control of Z-Source Converter Fed Separately excited DC motor with centrifugal Pump Set. Z-source converter can be used for both voltage buck and boost mode using LC impedance network. In this paper the dynamic modeling of Z-source with motor load and centrifugal pump set is carried out with new findings. The compensators for speed feedback loop are designed by taking average state space analysis and small signal model of the system. The feedback loop is designed by classical control methods. The experiment is done in MATLAB work environment and the result is verified by Simulation.

  13. Feedback Control and Dynamic Behaviour of Z-Source Converter Fed Separately Excited DC Motor and Centrifugal Pump Set

    OpenAIRE

    Saswati Swapna Dash; Byamakesh Nayak; Subrat Kumar

    2014-01-01

    This paper presents an overall study of Feedback Control of Z-Source Converter Fed Separately excited DC motor with centrifugal Pump Set. Z-source converter can be used for both voltage buck and boost mode using LC impedance network. In this paper the dynamic modeling of Z-source with motor load and centrifugal pump set is carried out with new findings. The compensators for speed feedback loop are designed by taking average state space analysis and small signal model of the system. The feedba...

  14. Single channel source separation of radar fuze mixed signal based on phase difference analysis

    Institute of Scientific and Technical Information of China (English)

    Hang ZHU; Shu-ning ZHANG; Hui-chang ZHAO

    2014-01-01

    A new method based on phase difference analysis is proposed for the single-channel mixed signal separation of single-channel radar fuze. This method is used to estimate the mixing coefficients of de-noised signals through the cumulants of mixed signals, solve the candidate data set by the mixing coefficients and signal analytical form, and resolve the problem of vector ambiguity by analyzing the phase differences. The signal separation is realized by exchanging data of the solutions. The waveform similarity coefficients are calculated, and the timeefrequency dis-tributions of separated signals are analyzed. The results show that the proposed method is effective.

  15. Anaerobic treatment in decentralised and source-separation-based sanitation concepts

    NARCIS (Netherlands)

    Kujawa-Roeleveld, K.; Zeeman, G.

    2006-01-01

    Anaerobic digestion of wastewater should be a core technology employed in decentralised sanitation systems especially when their objective is also resource conservation and reuse. The most efficient system involves separate collection and anaerobic digestion of the most concentrated domestic wastewa

  16. Exploiting Acoustic Similarity of Propagating Paths for Audio Signal Separation

    Directory of Open Access Journals (Sweden)

    Yin Bin

    2003-01-01

    Full Text Available Blind signal separation can easily find its position in audio applications where mutually independent sources need to be separated from their microphone mixtures while both room acoustics and sources are unknown. However, the conventional separation algorithms can hardly be implemented in real time due to the high computational complexity. The computational load is mainly caused by either direct or indirect estimation of thousands of acoustic parameters. Aiming at the complexity reduction, in this paper, the acoustic paths are investigated through an acoustic similarity index (ASI. Then a new mixing model is proposed. With closely spaced microphones (5–10 cm apart, the model relieves the computational load of the separation algorithm by reducing the number and length of the filters to be adjusted. To cope with real situations, a blind audio signal separation algorithm (BLASS is developed on the proposed model. BLASS only uses the second-order statistics (SOS and performs efficiently in frequency domain.

  17. Late Quaternary Blind Thrust Faults along the Southern Margin of the Cul-de-Sac Plain, Haiti: A Newly Recognized Seismic Source?

    Science.gov (United States)

    Briggs, R. W.; Prentice, C. S.; Crone, A. J.; Gold, R. D.; Hudnut, K. W.; Narcisse, R.

    2012-12-01

    hypothesis. In summary, the overall geomorphic expression of the folds in the broad, gently north-sloping Cul-de-Sac Plain is suggestive of late Quaternary activity. Because the folds are similar in orientation and style to the Léogâne fault and are located in similar positions north of the EPGF, they are likely underlain by blind thrust faults, and thus may represent additional earthquake sources that should be considered in seismic-hazard assessments for Port-au-Prince.

  18. Single-antenna Blind Signal Separation Algorithm for Time-frequency Overlapped Digital Communication Signal with Distinct Carrier Frequency%单天线接收时频混叠的异频数字通信信号盲源分离算法

    Institute of Scientific and Technical Information of China (English)

    庞利会; 王军; 唐斌

    2015-01-01

    本文针对单天线接收时频混叠数字通信信号的盲源分离问题,基于源信号之间载波差异性,构建单天线接收信号虚拟多通道模型,实现了源信号分离与重构。该算法通过对单天线接收混合信号进行短时傅里叶变换,分析各个中心频率的源信号频域特性,提取各个源信号的幅度与相位信息。利用提取信息,实现源信号分离与重构。仿真结果表明,该算法可以有效的实现单天线接收时频混叠数字通信信号的盲源分离。%In this paper,based on the carrier frequency distinct feature among original sources,a blind signal separation method is proposed for the single-antenna time-frequency overlapped digital communication signal.The method changes the single-antenna recording into multi-channel model based the feature that the carrier frequency of original sources are differ-ent from each other.Then,the method analyzes spectral information obtained by the short time Fourier transform to extract amplitude and phase values at each center frequency of overlapped signals.Using those extracted information enables sig-nals from single-antenna data to be separated and reconstructed.The simulation tests demonstrate the feasible feasibility of the proposed approach for single-channel time-frequency overlapped digital communication signal separation.

  19. Separation of radiated sound field components from waves scattered by a source under non-anechoic conditions

    DEFF Research Database (Denmark)

    Fernandez Grande, Efren; Jacobsen, Finn

    2010-01-01

    A method of estimating the sound field radiated by a source under non-anechoic conditions has been examined. The method uses near field acoustic holography based on a combination of pressure and particle velocity measurements in a plane near the source for separating outgoing and ingoing wave...... components. The outgoing part of the sound field is composed of both radiated and scattered waves. The method compensates for the scattered components of the outgoing field on the basis of the boundary condition of the problem, exploiting the fact that the sound field is reconstructed very close...... to the source. Thus the radiated free-field component is estimated simultaneously with solving the inverse problem of reconstructing the sound field near the source. The method is particularly suited to cases in which the overall contribution of reflected sound in the measurement plane is significant....

  20. Evaluation of a new pulping technology for pre-treating source-separated organic household waste prior to anaerobic digestion

    DEFF Research Database (Denmark)

    Naroznova, Irina; Møller, Jacob; Larsen, Bjarne;

    2016-01-01

    A new technology for pre-treating source-separated organic household waste prior to anaerobic digestion was assessed, and its performance was compared to existing alternative pre-treatment technologies. This pre-treatment technology is based on waste pulping with water, using a specially developed...... screw mechanism. The pre-treatment technology rejects more than 95% (wet weight) of non-biodegradable impurities in waste collected from households and generates biopulp ready for anaerobic digestion. Overall, 84-99% of biodegradable material (on a dry weight basis) in the waste was recovered......) to the produced biomass. The data generated in this study could be used for the environmental assessment of the technology and thus help in selecting the best pre-treatment technology for source separated organic household waste....

  1. Prospects of Source-Separation-Based Sanitation Concepts: A Model-Based Study

    NARCIS (Netherlands)

    Tervahauta, T.H.; Trang Hoang,; Hernández, L.; Zeeman, G.; Buisman, C.J.N.

    2013-01-01

    Separation of different domestic wastewater streams and targeted on-site treatment for resource recovery has been recognized as one of the most promising sanitation concepts to re-establish the balance in carbon, nutrient and water cycles. In this study a model was developed based on literature data

  2. Design and implementation of a space domain spherical microphone array with application to source localization and separation.

    Science.gov (United States)

    Bai, Mingsian R; Yao, Yueh Hua; Lai, Chang-Sheng; Lo, Yi-Yang

    2016-03-01

    In this paper, four delay-and-sum (DAS) beamformers formulated in the modal domain and the space domain for open and solid spherical apertures are examined through numerical simulations. The resulting beampatterns reveal that the mainlobe of the solid spherical DAS array is only slightly narrower than that of the open array, whereas the sidelobes of the modal domain array are more significant than those of the space domain array due to the discrete approximation of continuous spherical Fourier transformation. To verify the theory experimentally, a three-dimensionally printed spherical array on which 32 micro-electro-mechanical system microphones are mounted is utilized for localization and separation of sound sources. To overcome the basis mismatch problem in signal separation, source localization is first carried out using minimum variance distortionless response beamformer. Next, Tikhonov regularization (TIKR) and compressive sensing (CS) are employed to extract the source signal amplitudes. Simulations and experiments are conducted to validate the proposed spherical array system. Objective perceptual evaluation of speech quality test and a subjective listening test are undertaken in performance evaluation. The experimental results demonstrate better separation quality achieved by the CS approach than by the TIKR approach at the cost of computational complexity.

  3. Design and implementation of a space domain spherical microphone array with application to source localization and separation.

    Science.gov (United States)

    Bai, Mingsian R; Yao, Yueh Hua; Lai, Chang-Sheng; Lo, Yi-Yang

    2016-03-01

    In this paper, four delay-and-sum (DAS) beamformers formulated in the modal domain and the space domain for open and solid spherical apertures are examined through numerical simulations. The resulting beampatterns reveal that the mainlobe of the solid spherical DAS array is only slightly narrower than that of the open array, whereas the sidelobes of the modal domain array are more significant than those of the space domain array due to the discrete approximation of continuous spherical Fourier transformation. To verify the theory experimentally, a three-dimensionally printed spherical array on which 32 micro-electro-mechanical system microphones are mounted is utilized for localization and separation of sound sources. To overcome the basis mismatch problem in signal separation, source localization is first carried out using minimum variance distortionless response beamformer. Next, Tikhonov regularization (TIKR) and compressive sensing (CS) are employed to extract the source signal amplitudes. Simulations and experiments are conducted to validate the proposed spherical array system. Objective perceptual evaluation of speech quality test and a subjective listening test are undertaken in performance evaluation. The experimental results demonstrate better separation quality achieved by the CS approach than by the TIKR approach at the cost of computational complexity. PMID:27036243

  4. 超大动态范围日盲紫外辐照度光源%A Solar Blind Light Source with Long Dynamic Range

    Institute of Scientific and Technical Information of China (English)

    周跃; 闫丰; 章明朝; 高松涛

    2012-01-01

    In order to realize the irradiance calibration of SBUV-ICCD (solar blind ultraviolent Intensified change-coupled device) with dynamic range reaching 120 dB, a light source with long dynamic range was designed and realized. Firstly, the irradiance dynamic range was estimated. Then using deuterium lamp, integrating sphere, precise stop and rail, an ultraviolent light source was developed, which has fixed structure of spectrum, but the irradiance can change continuously in long range. At last the light source's performance was tested. The result shows that the irradiance between 0. 278 and 2.8×10-7 μW·cm-2 was covered, and the stability was 0. 93%/3 h. So the demand of calibration of irradiance was satisfied. It will help for measuring the surface uniformity of detector and the calibration of imaging systems.%为实现对动态范围达120dB的日盲紫外增强型电荷耦合器件(SBUV-ICCD)的辐照度定标,设计并实现了超大动态范围日盲紫外辐照度光源.首先估算出SBUV-ICCD的辐照度定标所需的动态范围,其次采用氘灯、积分球、高精度光阑及平直光轨等,基于辐照度距离平方反比定律实现了光谱结构不变,而辐照度在极大动态范围内连续变化的光源,并对其进行了动态范围及稳定性测试.结果表明,该光源实际覆盖辐照度0.278~2.8× 10-7 μW·cm-2,稳定性为0.93%/3 h,能够满足SBUV-ICCD定标的需要,且可复用于紫外探测器面均匀性测试、成像系统辐亮度定标等.

  5. 基于模糊逻辑的亚高斯与超高斯源混合盲分离%Blind separation for the mixtures of sub-and super-Gaussian signals based on fuzzy logic

    Institute of Scientific and Technical Information of China (English)

    刘宁; 张伟涛; 楼顺天; 冶继民

    2011-01-01

    The problem of simultaneous blind separation of sub-and super-Gaussian signals is addressed.Firstly, a mixture density model suitable for the case where these two types signals exist simultaneously is proposed. Then the nonlinear function is computed according to this density model. A unifying algorithm for separating these two type signals is obtained in the end. On the other hand, the fuzzy inference system to determine the step length of the proposed adaptive algorithm on line is applied. Therefore, the learning algorithm has faster convergence speed and smaller steady state error. Simulation experiments of separating phonetic signals and artificial synthetical signals demonstrate the validity of the proposed algorithm, and the interference-to-signal ratio (ISR) is calculated to describe the extension of the improvement of the proposed algorithm.%对于同时存在亚高斯和超高斯源信号的盲信号分离问题,提出了适用于两类信号同时存在的合成概率模型,并以此概率模型计算非线性函数得到了分离两类信号的统一算法.同时,引入模糊推理系统在线确定自适应算法的迭代步长,因此学习算法的收敛速度更快,而且稳态误差更小.仿真实验分别通过对语音信号以及人工合成信号的分离,验证算法的有效性,并通过计算分离信号的干扰信号比(interference-to-signal ratio,ISR),证明提出的算法能够更好、更快地分离亚高斯与超高斯混合信号.

  6. A simple alkali-metal and noble gas ion source for SIMS equipments with mass separation of the primary ions

    International Nuclear Information System (INIS)

    An alkali-metal ion source working without a store of alkali-metals is described. The alkali-metal ions are produced by evaporation of alkali salts and ionization in a low-voltage arc discharge stabilized with a noble gas plasma or in the case of small alkali-metal ion currents on the base of the well known thermic ionization at a hot tungsten wire. The source is very simple in construction and produces a stable ion current of 0.3 μA for more than 100 h. It is possible to change the ion species in a short time. This source is applicable to all SIMS equipments using mass separation for primary ions. (author)

  7. Numerical study of the effect of an embedded surface-heat source on the separation bubble of supersonic flow

    Science.gov (United States)

    Degani, D.

    1983-01-01

    A numerical study of the conjugated problem of a separated supersonic flow field and a conductive solid wall with an embedded heat source is presented. Implicit finite-difference schemes were used to solve the two-dimensional time-dependent compressible Navier-Stokes equations and the time-dependent heat-conduction equation for the solid in both general coordinate systems. A detailed comparison between the thin-layer and Navier-Stokes models was made for steady and unsteady supersonic flow and showed insignificant differences. Steady-state and transient cases were computed and the results show that a temperature pulse at the solid-fluid interface can be used to detect the flow direction near the wall in the vicinity of separation without significant distortion of the flow field.

  8. Multichannel Blind Signal Adaptive Separation Algorithm Based on Polyspectra Analysis%基于聚谱分析的多通道盲信号自适应分离算法

    Institute of Scientific and Technical Information of China (English)

    张兰勇; 刘繁明; 李冰

    2014-01-01

    该文提出一种在多传感器中多种信号混叠的分离方法。该方法通过分析传感器数据的聚谱来提取未知信号,并利用线性方程基本算法估计有限脉冲响应的耦合系统,该方法对于多通道谱重叠的有色输入信号盲解卷积十分有效。作为该算法的扩展,可以应用于包括准周期信号等非平稳信号的分离。并将该算法应用于电磁辐射的测试,仿真结果证明了其有效性和快速性。%A separation method of multiple signals from their superposition recorded at several sensors is addressed. The method employs polyspectra of the sensor data to extract the unknown signals and estimate the Finite Impulse Response (FIR) coupling systems via a linear equation basic algorithm. The method is useful for multichannel blind deconvolution of colored input signals with (possibly) overlapping spectra. An extension of the main algorithm, which can be applied to non-stationary signals separation such as quasiperiodic signal, is also given. What’s more, the method is applied to electromagnetic radiation measurement. Simulation results verify the effectiveness of the algorithm.

  9. Anaerobic treatment as a core technology for energy, nutrients and water recovery from source-separated domestic waste(water).

    Science.gov (United States)

    Zeeman, Grietje; Kujawa, Katarzyna; de Mes, Titia; Hernandez, Lucia; de Graaff, Marthe; Abu-Ghunmi, Lina; Mels, Adriaan; Meulman, Brendo; Temmink, Hardy; Buisman, Cees; van Lier, Jules; Lettinga, Gatze

    2008-01-01

    Based on results of pilot scale research with source-separated black water (BW) and grey water (GW), a new sanitation concept is proposed. BW and GW are both treated in a UASB (-septic tank) for recovery of CH4 gas. Kitchen waste is added to the anaerobic BW treatment for doubling the biogas production. Post-treatment of the effluent is providing recovery of phosphorus and removal of remaining COD and nitrogen. The total energy saving of the new sanitation concept amounts to 200 MJ/year in comparison with conventional sanitation, moreover 0.14 kg P/p/year and 90 litres of potential reusable water are produced.

  10. Noise-Source Separation Using Internal and Far-Field Sensors for a Full-Scale Turbofan Engine

    Science.gov (United States)

    Hultgren, Lennart S.; Miles, Jeffrey H.

    2009-01-01

    Noise-source separation techniques for the extraction of the sub-dominant combustion noise from the total noise signatures obtained in static-engine tests are described. Three methods are applied to data from a static, full-scale engine test. Both 1/3-octave and narrow-band results are discussed. The results are used to assess the combustion-noise prediction capability of the Aircraft Noise Prediction Program (ANOPP). A new additional phase-angle-based discriminator for the three-signal method is also introduced.

  11. Operation of a high temperature ion source at the helium-jet on-line isotope separator facility HELIOS

    Energy Technology Data Exchange (ETDEWEB)

    Bruegger, M.; Hildebrand, N.; Karlewski, T.; Trautmann, N. (Mainz Univ. (Germany, F.R.). Inst. fuer Kernchemie); Mazumdar, A.K. (Marburg Univ. (Germany, F.R.). Fachbereich Physik); Herrmann, G. (Mainz Univ. (Germany, F.R.). Inst. fuer Kernchemie; Gesellschaft fuer Schwerionenforschung m.b.H., Darmstadt (Germany, F.R.))

    1985-02-01

    The performance of a high temperature ion source coupled to a helium gas-jet transport system for an efficient mass separation of neutron-rich alkaline earth and lanthanide isotopes is reported and the results of overall efficiency measurements using different cluster materials in the gas-jet are given. A fast, microprocessor controlled tape transport system for ..gamma..-spectroscopic studies on short-lived isotopes is described. Some results on the decay of 3.8sub(-s) /sup 152/Pr are presented.

  12. Hydrocyclonic separation of invasive New Zealand mudsnails from an aquaculture water source

    Science.gov (United States)

    Nielson, R. Jordan; Moffitt, Christine M.; Watten, Barnaby J.

    2012-01-01

    Invasive New Zealand mudsnails (Potamopyrgus antipodarum, NZMS) have infested freshwater aquaculture facilities in the western United States and disrupted stocking or fish transportation activities because of the risk of transporting NZMS to naive locations. We tested the efficacy of a gravity-fed, hydrocyclonicseparation system to remove NZMS from an aquaculture water source at two design flows: 367 L/min and 257 L/min. The hydrocyclone effectively filtered all sizes of snails (including newly emerged neonates) from inflows. We modeled cumulative recovery of three sizes of snails, and determined that both juvenile and adult sized snails were transported similarly through the filtration system, but the transit of neonates was faster and similar to the transport of water particles. We found that transit times through the filtration system were different between the two flows regardless of snail size, and the hydrocyclone filter operated more as a plug flow system with dispersion, especially when transporting and removing the larger sized adult and juvenile sized snails. Our study supports hydrocyclonic filtration as an important tool to provide snail free water for aquaculture operations that require uninfested water sources.

  13. Query-by-Example Music Information Retrieval by Score-Informed Source Separation and Remixing Technologies

    Directory of Open Access Journals (Sweden)

    Goto Masataka

    2010-01-01

    Full Text Available We describe a novel query-by-example (QBE approach in music information retrieval that allows a user to customize query examples by directly modifying the volume of different instrument parts. The underlying hypothesis of this approach is that the musical mood of retrieved results changes in relation to the volume balance of different instruments. On the basis of this hypothesis, we aim to clarify the relationship between the change in the volume balance of a query and the genre of the retrieved pieces, called genre classification shift. Such an understanding would allow us to instruct users in how to generate alternative queries without finding other appropriate pieces. Our QBE system first separates all instrument parts from the audio signal of a piece with the help of its musical score, and then it allows users remix these parts to change the acoustic features that represent the musical mood of the piece. Experimental results showed that the genre classification shift was actually caused by the volume change in the vocal, guitar, and drum parts.

  14. Impact of organic polyelectrolytes on coagulation of source-separated black water.

    Science.gov (United States)

    Kozminykh, Pavlo; Heistad, Arve; Ratnaweera, Harsha C; Todt, Daniel

    2016-07-01

    Household wastewater is originated from common people's activities and has a potential harmful impact on the environment if discharged directly without proper treatment. Toilet wastewater or black water (BW) contains urine, faeces, toilet paper and flushing water and it contains the majority of pollutants obtained from a single household. In this study, the focus was on BW treatment using chemical methods. The main goal of current research was to define the possibility and applicability of conventional coagulants and flocculants in direct chemical treatment of vacuum-collected BW to remove particles, organic matter and phosphorous. After the definition of dosing ranges, based on the equivalent doses in conventional municipal and industrial wastewater treatment data, aluminium and iron coagulants, organic polyelectrolytes (polymers with anionic, neutral and cationic charge with different molecular weights) and their various combinations were tested using the well-known jar-test laboratory method to study aggregation and solid-liquid separation processes in raw BW. The most important process parameter during the coagulation was pH level, dependent on the type and doses of metal salts. Some side processes were found to occur while using iron-based coagulants. Dosing of either single coagulants or single polymers did not give satisfactory results, while a combination of aluminium salts and cationic polymers showed high removal rates in total suspended solids, total chemical oxygen demand and ortho-phosphates, reaching 97.8%, 92% and 98.6%, respectively, with the optimal doses of chemicals. Cationic polymers with the lowest molecular weight and highest charge density were the most efficient in combination with aluminium coagulants. PMID:26672384

  15. An investigation of the usability of sound recognition for source separation of packaging wastes in reverse vending machines.

    Science.gov (United States)

    Korucu, M Kemal; Kaplan, Özgür; Büyük, Osman; Güllü, M Kemal

    2016-10-01

    In this study, we investigate the usability of sound recognition for source separation of packaging wastes in reverse vending machines (RVMs). For this purpose, an experimental setup equipped with a sound recording mechanism was prepared. Packaging waste sounds generated by three physical impacts such as free falling, pneumatic hitting and hydraulic crushing were separately recorded using two different microphones. To classify the waste types and sizes based on sound features of the wastes, a support vector machine (SVM) and a hidden Markov model (HMM) based sound classification systems were developed. In the basic experimental setup in which only free falling impact type was considered, SVM and HMM systems provided 100% classification accuracy for both microphones. In the expanded experimental setup which includes all three impact types, material type classification accuracies were 96.5% for dynamic microphone and 97.7% for condenser microphone. When both the material type and the size of the wastes were classified, the accuracy was 88.6% for the microphones. The modeling studies indicated that hydraulic crushing impact type recordings were very noisy for an effective sound recognition application. In the detailed analysis of the recognition errors, it was observed that most of the errors occurred in the hitting impact type. According to the experimental results, it can be said that the proposed novel approach for the separation of packaging wastes could provide a high classification performance for RVMs.

  16. An investigation of the usability of sound recognition for source separation of packaging wastes in reverse vending machines.

    Science.gov (United States)

    Korucu, M Kemal; Kaplan, Özgür; Büyük, Osman; Güllü, M Kemal

    2016-10-01

    In this study, we investigate the usability of sound recognition for source separation of packaging wastes in reverse vending machines (RVMs). For this purpose, an experimental setup equipped with a sound recording mechanism was prepared. Packaging waste sounds generated by three physical impacts such as free falling, pneumatic hitting and hydraulic crushing were separately recorded using two different microphones. To classify the waste types and sizes based on sound features of the wastes, a support vector machine (SVM) and a hidden Markov model (HMM) based sound classification systems were developed. In the basic experimental setup in which only free falling impact type was considered, SVM and HMM systems provided 100% classification accuracy for both microphones. In the expanded experimental setup which includes all three impact types, material type classification accuracies were 96.5% for dynamic microphone and 97.7% for condenser microphone. When both the material type and the size of the wastes were classified, the accuracy was 88.6% for the microphones. The modeling studies indicated that hydraulic crushing impact type recordings were very noisy for an effective sound recognition application. In the detailed analysis of the recognition errors, it was observed that most of the errors occurred in the hitting impact type. According to the experimental results, it can be said that the proposed novel approach for the separation of packaging wastes could provide a high classification performance for RVMs. PMID:27378630

  17. On-line experimental results of an argon gas cell-based laser ion source (KEK Isotope Separation System)

    Science.gov (United States)

    Hirayama, Y.; Watanabe, Y. X.; Imai, N.; Ishiyama, H.; Jeong, S. C.; Jung, H. S.; Miyatake, H.; Oyaizu, M.; Kimura, S.; Mukai, M.; Kim, Y. H.; Sonoda, T.; Wada, M.; Huyse, M.; Kudryavtsev, Yu.; Van Duppen, P.

    2016-06-01

    KEK Isotope Separation System (KISS) has been developed at RIKEN to produce neutron rich isotopes with N = 126 to study the β -decay properties for application to astrophysics. The KISS is an element-selective mass-separation system which consists of an argon gas cell-based on laser ion source for atomic number selection and an ISOL mass-separation system. The argon gas cell of KISS is a key component to stop and collect the unstable nuclei produced in a multi-nucleon transfer reaction, where the isotopes of interest will be selectively ionized using laser resonance ionization. We have performed off- and on-line experiments to study the basic properties of the gas cell as well as of the KISS. We successfully extracted the laser-ionized stable 56Fe (direct implantation of a 56Fe beam into the gas cell) atoms and 198Pt (emitted from the 198Pt target by elastic scattering with a 136Xe beam) atoms from the KISS during the commissioning on-line experiments. We furthermore extracted laser-ionized unstable 199Pt atoms and confirmed that the measured half-life was in good agreement with the reported value.

  18. Kilohertz Quasi-Periodic Oscillation Peak Separation is not Constant in the Atoll Source 4U 1608-52

    CERN Document Server

    Méndez, M; Wijnands, R; Ford, E C; Van Paradijs, J; Vaughan, B A; Méndez, Mariano; Van der Klis, Michiel; Wijnands, Rudy; Ford, Eric C.; Van Paradijs, Jan; Vaughan, Brian A.

    1998-01-01

    We present new Rossi X-ray Timing Explorer observations of the low-mass X-ray binary 4U 1608-52 during the decay of its 1998 outburst. We detect by a direct FFT method the existence of a second kilohertz quasi-periodic oscillation (kHz QPO) in its power density spectrum, previously only seen by means of the sensitivity-enhancing `shift and add' technique. This result confirms that 4U 1608-52 is a twin kHz QPO source. The frequency separation between these two QPO decreased significantly, from 325.5 +/- 3.4 Hz to 225.3 +/- 12.0 Hz, as the frequency of the lower kHz QPO increased from 470 Hz to 865 Hz, in contradiction with a simple beat-frequency interpretation. This change in the peak separation of the kHz QPOs is closely similar to that previously seen in Sco X-1, but takes place at a ten times lower average luminosity. We discuss this result within the framework of models that have been proposed for kHz QPO. Beat frequency models where the peak separation is identified with the neutron star spin rate, as we...

  19. Quantitative assessment of distance to collection point and improved sorting information on source separation of household waste.

    Science.gov (United States)

    Rousta, Kamran; Bolton, Kim; Lundin, Magnus; Dahlén, Lisa

    2015-06-01

    The present study measures the participation of households in a source separation scheme and, in particular, if the household's application of the scheme improved after two interventions: (a) shorter distance to the drop-off point and (b) easy access to correct sorting information. The effect of these interventions was quantified and, as far as possible, isolated from other factors that can influence the recycling behaviour. The study was based on households located in an urban residential area in Sweden, where waste composition studies were performed before and after the interventions by manual sorting (pick analysis). Statistical analyses of the results indicated a significant decrease (28%) of packaging and newsprint in the residual waste after establishing a property close collection system (intervention (a)), as well as significant decrease (70%) of the miss-sorted fraction in bags intended for food waste after new information stickers were introduced (intervention (b)). Providing a property close collection system to collect more waste fractions as well as finding new communication channels for information about sorting can be used as tools to increase the source separation ratio. This contribution also highlights the need to evaluate the effects of different types of information and communication concerning sorting instructions in a property close collection system. PMID:25817721

  20. Evaluation of a new pulping technology for pre-treating source-separated organic household waste prior to anaerobic digestion.

    Science.gov (United States)

    Naroznova, Irina; Møller, Jacob; Larsen, Bjarne; Scheutz, Charlotte

    2016-04-01

    A new technology for pre-treating source-separated organic household waste prior to anaerobic digestion was assessed, and its performance was compared to existing alternative pre-treatment technologies. This pre-treatment technology is based on waste pulping with water, using a specially developed screw mechanism. The pre-treatment technology rejects more than 95% (wet weight) of non-biodegradable impurities in waste collected from households and generates biopulp ready for anaerobic digestion. Overall, 84-99% of biodegradable material (on a dry weight basis) in the waste was recovered in the biopulp. The biochemical methane potential for the biopulp was 469±7mL CH4/g ash-free mass. Moreover, all Danish and European Union requirements regarding the content of hazardous substances in biomass intended for land application were fulfilled. Compared to other pre-treatment alternatives, the screw-pulping technology showed higher biodegradable material recovery, lower electricity consumption and comparable water consumption. The higher material recovery achieved with the technology was associated with greater transfer of nutrients (N and P), carbon (total and biogenic) but also heavy metals (except Pb) to the produced biomass. The data generated in this study could be used for the environmental assessment of the technology and thus help in selecting the best pre-treatment technology for source separated organic household waste. PMID:26868847

  1. Analysis of Fast- ICA Algorithm for Separation of Mixed Images

    Directory of Open Access Journals (Sweden)

    Tanmay Awasthy

    2013-10-01

    Full Text Available Independent component analysis (ICA is a newly developed method in which the aim is to find a linear representation of nongaussian statistics so that the components are statistically independent, or as independent as possible. Such techniques are actively being used in study of both statistical image processing and unsupervised neural learning application. This paper represents the Fast Independent component analysis algorithm for separation of mixed images. To solve the blind signal separation problems Independent component analysis approach used statistical independence of the source signals. This paper focuses on the theory and methods of ICA in contrast to classical transformations along with the applications of this method to blind source separation .For an illustration of the algorithm, visualized the immixing process with a set of images has been done. To express the results of our analysis simulations have been presented.

  2. Resolving Trends in Antarctic Ice Sheet Mass Loss and Glacio-isostatic Adjustment Through Spatio-temporal Source-separation

    Science.gov (United States)

    Bamber, J. L.; Schoen, N.; Zammit-Mangion, A.; Rougier, J.; Flament, T.; Luthcke, S. B.; Petrie, E. J.; Rémy, F.

    2013-12-01

    There remains considerable inconsistency between different methods and approaches for determining ice mass trends for Antarctica from satellite observations. There are three approaches that can provide near global coverage for mass trends: altimetry, gravimetry and mass budget calculations. All three approaches suffer from a source separation problem where other geophysical processes limit the capability of the method to resolve the origin and magnitude of a mass change. A fourth approach, GPS vertical motion, provides localised estimates of mass change due to elastic uplift and an indirect estimate of GIA. Each approach has different source separation issues and different spatio-temporal error characteristics. In principle, it should be possible to combine the data and process covariances to minimize the uncertainty in the solution and to produce robust, posterior errors for the trends. In practice, this is a challenging problem in statistics because of the large number of degrees of freedom, the variable spatial and temporal sampling between the different observations and the fact that some processes remain under-sampled, such as firn compaction. Here, we present a novel solution to this problem using the latest methods in statistical modelling of spatio-temporal processes. We use Bayesian hierarchical modelling and employ stochastic partial differential equations to capture our physical understanding of the key processes that influence our observations. Due to the huge number of observations involved (> 10^8) methods are required to reduce the dimensionality of the problem and care is required in treatment of the observations as they are not independent. Here, we focus mainly on the results rather than the full suite of methods and we present time evolving fields of surface mass balance, ice dynamic-driven mass loss, and firn compaction for the period 2003-2009, derived from a combination of ICESat, ENVISAT, GRACE, InSAR, GPS and regional climate model output

  3. Characterisation of the biochemical methane potential (BMP) of individual material fractions in Danish source-separated organic household waste

    DEFF Research Database (Denmark)

    Naroznova, Irina; Møller, Jacob; Scheutz, Charlotte

    2016-01-01

    This study is dedicated to characterising the chemical composition and biochemical methane potential (BMP) of individual material fractions in untreated Danish source-separated organic household waste (SSOHW). First, data on SSOHW in different countries, available in the literature, were evaluated...... and then, secondly, laboratory analyses for eight organic material fractions comprising Danish SSOHW were conducted. No data were found in the literature that fully covered the objectives of the present study. Based on laboratory analyses, all fractions were assigned according to their specific properties...... in Denmark (untreated) was calculated, and the BMP contribution of the individual material fractions was then evaluated. Material fractions of the two general waste types, defined as "food waste" and "fibre-rich waste," were found to be anaerobically degradable with considerable BMP. Material degradability...

  4. Separate norovirus outbreaks linked to one source of imported frozen raspberries by molecular analysis, Denmark, 2010–2011

    DEFF Research Database (Denmark)

    Müller, L.; Schultz, Anna Charlotte; Fonager, J.;

    2015-01-01

    Norovirus outbreaks occur frequently in Denmark and it can be difficult to establish whether apparently independent outbreaks have the same origin. Here we report on six outbreaks linked to frozen raspberries, investigated separately over a period of 3 months. Norovirus from stools were sequence...... capsid P2 region. In one outbreak at a hospital canteen, frozen raspberries was associated with illness by cohort investigation (relative risk 6·1, 95% confidence interval 3·2–11). Bags of raspberries suspected to be the source were positive for genogroup I and II noroviruses, one typable virus...... was genotype GI.6 (capsid). These molecular investigations showed that the apparently independent outbreaks were the result of one contamination event of frozen raspberries. The contaminated raspberries originated from a single producer in Serbia and were originally not considered to belong to the same batch...

  5. Separation of the low-frequency atmospheric variability into non-Gaussian multidimensional sources by Independent Subspace Analysis

    Science.gov (United States)

    Pires, Carlos; Ribeiro, Andreia

    2016-04-01

    An efficient nonlinear method of statistical source separation of space-distributed non-Gaussian distributed data is proposed. The method relies in the so called Independent Subspace Analysis (ISA), being tested on a long time-series of the stream-function field of an atmospheric quasi-geostrophic 3-level model (QG3) simulating the winter's monthly variability of the Northern Hemisphere. ISA generalizes the Independent Component Analysis (ICA) by looking for multidimensional and minimally dependent, uncorrelated and non-Gaussian distributed statistical sources among the rotated projections or subspaces of the multivariate probability distribution of the leading principal components of the working field whereas ICA restrict to scalar sources. The rationale of that technique relies upon the projection pursuit technique, looking for data projections of enhanced interest. In order to accomplish the decomposition, we maximize measures of the sources' non-Gaussianity by contrast functions which are given by squares of nonlinear, cross-cumulant-based correlations involving the variables spanning the sources. Therefore sources are sought matching certain nonlinear data structures. The maximized contrast function is built in such a way that it provides the minimization of the mean square of the residuals of certain nonlinear regressions. The issuing residuals, followed by spherization, provide a new set of nonlinear variable changes that are at once uncorrelated, quasi-independent and quasi-Gaussian, representing an advantage with respect to the Independent Components (scalar sources) obtained by ICA where the non-Gaussianity is concentrated into the non-Gaussian scalar sources. The new scalar sources obtained by the above process encompass the attractor's curvature thus providing improved nonlinear model indices of the low-frequency atmospheric variability which is useful since large circulation indices are nonlinearly correlated. The non-Gaussian tested sources (dyads and

  6. Source Separation of Urine as an Alternative Solution to Nutrient Management in Biological Nutrient Removal Treatment Plants.

    Science.gov (United States)

    Jimenez, Jose; Bott, Charles; Love, Nancy; Bratby, John

    2015-12-01

    Municipal wastewater contains a mixture of brown (feces and toilet paper), yellow (urine), and gray (kitchen, bathroom and wash) waters. Urine contributes approximately 70-80% of the nitrogen (N), 50-70% of the phosphorus (P) load and 60-70% of the pharmaceutical residues in normal domestic sewage. This study evaluated the impact of different levels of source separation of urine on an existing biological nutrient removal (BNR) process. A process model of an existing biological nutrient removal (BNR) plant was used. Increasing the amount of urine diverted from the water reclamation facilities, has little impact on effluent ammonia (NH₃-N) concentration, but effluent nitrate (NO₃-N) concentration decreases. If nitrification is necessary then no reduction in the sludge age can be realized. However, a point is reached where the remaining influent nitrogen load matches the nitrogen requirements for biomass growth, and no residual nitrogen needs to be nitrified. That allows a significant reduction in sludge age, implying reduced process volume requirements. In situations where nitrification is required, lower effluent nitrate (NO₃-N) concentrations were realized due to both the lower influent nitrogen content in the wastewater and a more favorable nitrogen-to-carbon ratio for denitrification. The external carbon requirement for denitrification decreases as the urine separation efficiency increases due to the lower influent nitrogen content in the wastewater and a more favorable nitrogen-to-carbon ratio for denitrification. The effluent phosphorus concentration decreases when the amount of urine sent to water reclamation facilities is decreased due to lower influent phosphorus concentrations. In the case of chemical phosphate removal, urine separation reduces the amount of chemicals required. PMID:26652123

  7. The effect of urine storage on antiviral and antibiotic compounds in the liquid phase of source-separated urine.

    Science.gov (United States)

    Jaatinen, Sanna T; Palmroth, Marja R T; Rintala, Jukka A; Tuhkanen, Tuula A

    2016-09-01

    The behaviour of pharmaceuticals related to the human immunodeficiency virus treatment was studied in the liquid phase of source-separated urine during six-month storage at 20°C. Six months is the recommended time for hygienization and use of urine as fertilizer. Compounds were spiked in urine as concentrations calculated to appear in urine. Assays were performed with separate compounds and as therapeutic groups of antivirals, antibiotics and anti-tuberculotics. In addition, urine was amended either with faeces or urease inhibitor. The pharmaceutical concentrations were monitored from filtered samples with solid phase extraction and liquid chromatography. The concentration reductions of the studied compounds as such or with amendments ranged from less than 1% to more than 99% after six-month storage. The reductions without amendments were 41.9-99% for anti-tuberculotics; <52% for antivirals (except with 3TC 75.6%) and <50% for antibiotics. In assays with amendments, the reductions were all <50%. Faeces amendment resulted in similar or lower reduction than without it even though bacterial activity should have increased. The urease inhibitor prevented ureolysis and pH rise but did not affect pharmaceutical removal. In conclusion, removal during storage might not be enough to reduce risks associated with the studied pharmaceuticals, in which case other feasible treatment practises or urine utilization means should be considered. PMID:26804243

  8. Vision - night blindness

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003039.htm Vision - night blindness To use the sharing features on ... page, please enable JavaScript. Night blindness is poor vision at night or in dim light. Considerations Night ...

  9. Onchocerciasis (River Blindness) FAQs

    Science.gov (United States)

    ... The CDC Parasites - Onchocerciasis (also known as River Blindness) Note: Javascript is disabled or is not supported ... infected Simulium blackfly. It is also called River Blindness because the fly that transmits infection breeds in ...

  10. Blind extraction of exoplanetary spectra

    Science.gov (United States)

    Morello, Giuseppe; Waldmann, Ingo P.; Tinetti, Giovanna

    2016-06-01

    In the last decade, remote sensing spectroscopy enabled characterization of the atmospheres of extrasolar planets. Transmission and emission spectra of tens of transiting exoplanets have been measured with multiple instruments aboard Spitzer and Hubble Space Telescopes as well as ground-based facilities, revealing the presence of atomic, ionic and molecular species in their atmospheres, and constraining their temperature and pressure profiles.Early analyses were somehow heuristic both in measuring the spectra and in their interpretation, leading to some controversies in the literature.A photometric precision of 0.01% is necessary to detect the atmospheric spectral modulations. Current observatories, except Kepler, were not designed to achieve this precision. Data reduction is necessary to minimize the effect of instrument systematics in order to achieve the target precision. In the past, parametric models have extensively been used by most teams to remove correlated noise with the aid of auxiliary information of the instrument, the so-called optical state vectors (OSVs). Such OSVs can include inter- and intra-pixel position of the star or its spectrum, instrument temperatures and inclinations, and/or other parameters. In some cases, different parameterizations led to discrepant results.We recommend the use of blind non-parametric data detrending techniques to overcome those issues. In particular, we adopt Independent Component Analysis (ICA), i.e. a blind source separation (BSS) technique to disentangle the multiple instrument systematics and astrophysical signals in transit/eclipse light curves. ICA does not require a model for the systematics, and for this reason, it can be applied to any instrument with little changes, if any. ICA-based algorithms have been applied to Spitzer/IRAC and synthetic observations in photometry (Morello et al. 2014, 2015, 2016; Morello 2015) and to Hubble/NICMOS and Spitzer/IRS in spectroscopy (Waldmann 2012, 2014, Waldmann et al. 2013

  11. 单传感器声纳浮标场的盲分离算法%Blind source separation for sonobuoy field with single sensor

    Institute of Scientific and Technical Information of China (English)

    许策; 章新华; 范永峰

    2007-01-01

    声纳浮标作为海上反潜力量的重要组成部分之一,具有隐蔽性能好,探测范围广等优点.单传感器声纳浮标作为声纳浮标的一种,因其结构简单而具有广泛的应用.文章以被动接收为背景,尝试用盲分离技术综合多个单传感器声纳浮标的输出对目标辐射信号进行恢复,仿真实验验证了盲分离技术的可行性.

  12. [The punishment of blinding and the life of the blind].

    Science.gov (United States)

    Büttner, Jan Ulrich

    2009-01-01

    The article deals with a group of people who were deprived of their eyesight by private acts of force or by executions of lawful sentences. In early medieval texts blinding is frequently mentioned in connection with popes, kings, princes or bishops. However, since the High Middle Ages these dignitaries were increasingly spared the loss of their eyes. It may be said that on the whole, from the eighth to the twelfth century, blinding was overwhelmingly used to dispose of political adversaries, but did then rapidly turn into a criminal punishment. In the earliest 'Landfriedensordnungen' of the late eleventh century, the loss of the perpetrator's eyes crops up as punishment for breach of the peace, while later it was applied to a variety of more or less serious offences. The destiny of the blinded in the early Middle Ages is only highlighted by sketches of a few individual cases; for the High and late Middle Ages--apart from a few notable exceptions--it is only possible to reflect on the general situation of blind people in society, since the sources usually do not differentiate between those having lost their sight through human violence or due to other causes. PMID:20506724

  13. Research on the charge weight and the sound source level of underwater separation of pyrotechnic separation device%火工分离装置水下分离噪声与装药量研究

    Institute of Scientific and Technical Information of China (English)

    陈霞; 田荣艳

    2012-01-01

    通过对火工分离装置水下分离噪声产生机理的分析和研究,在满足分离裕度的情况下,研究一种专用火工分离装置,探寻装药量与分离噪声声源级的关系,进行水下噪声对比测试,其研究结果对水中兵器水下分离降嗓设计提供依据.%Based on the analysis and study for the noise generation mechanism of pyrotechnically actuated separation devices which separate underwater, when meet the case of separated margin, study a special pyrotechnical separation device to explore the relationship between the charge weight and the sound source level,and develop the tests for underwater noise. The results provide the basis for noising-reducing of underwater weapons.

  14. Mothers 'don't like it; never tried it': Blind Sensory Test of a Homemade Chicken Liver Baby Food, a Source of Iron, by Infants and their Mothers.

    Science.gov (United States)

    Campos, Viviani Jaques; Morais, Tania Beninga

    2015-08-01

    A homemade chicken liver baby food (CLBF) that meets infants' nutritional requirements was developed and its acceptance by children and their mothers determined. CLBF's nutritional content was determined by chemical analyses. A blind sensory test (ST) by 50 infants 7-12 months old and their mothers of CLBF and ground beef baby food (GBBF) was applied. Mothers' preferences for liver and beef, answers of an hedonic scale and infants' acceptance were investigated. CLBF met the nutritional requirements for infants. There were no significant differences in the ST between the CLBF and GBBF, either for infants or for their mothers. There was no correlation between mothers' like or dislike of liver and the ST scores. Infants tried and liked the CLBF that match dietary recommendations and could help prevent iron deficiency. Mothers, on the other hand, demonstrated an 'I don't like it; I never tried it' attitude. PMID:26116829

  15. Isomer separation of $^{70g}Cu$ and $^{70m}Cu$ with a resonance ionization laser ion source

    CERN Document Server

    Köster, U; Mishin, V I; Weissman, L; Huyse, M; Kruglov, K; Müller, W F; Van Duppen, P; Van Roosbroeck, J; Thirolf, P G; Thomas, H C; Weisshaar, D W; Schulze, W; Borcea, R; La Commara, M; Schatz, H; Schmidt, K; Röttger, S; Huber, G; Sebastian, V; Kratz, K L; Catherall, R; Georg, U; Lettry, Jacques; Oinonen, M; Ravn, H L; Simon, H

    2000-01-01

    Radioactive copper isotopes were ionized with the resonance ionization laser ion source at the on-line isotope separator ISOLDE (CERN). Using the different hyperfine structure in the 3d/sup 10/ 4s /sup 2/S/sub 1/2/-3d/sup 10/ 4p /sup 2/P/sub 1/2//sup 0/ transition the low- and high-spin isomers of /sup 70/Cu were selectively enhanced by tuning the laser wavelength. The light was provided by a narrow-bandwidth dye laser pumped by copper vapor lasers and frequency doubled in a BBO crystal. The ground state to isomeric state intensity ratio could be varied by a factor of 30, allowing to assign gamma transitions unambiguously to the decay of the individual isomers. It is shown that the method can also be used to determine magnetic moments. In a first experiment for the 1/sup +/ ground state of /sup 70/Cu a magnetic moment of (+)1.8(3) mu /sub N/ and for the high-spin isomer of /sup 70/Cu a magnetic moment of (+or-)1.2(3) mu /sub N/ could be deduced. (20 refs).

  16. Verification of a two-layer inverse Monte Carlo absorption model using multiple source-detector separation diffuse reflectance spectroscopy.

    Science.gov (United States)

    Sharma, Manu; Hennessy, Ricky; Markey, Mia K; Tunnell, James W

    2013-12-01

    A two-layer Monte Carlo lookup table-based inverse model is validated with two-layered phantoms across physiologically relevant optical property ranges. Reflectance data for source-detector separations of 370 μm and 740 μm were collected from these two-layered phantoms and top layer thickness, reduced scattering coefficient and the top and bottom layer absorption coefficients were extracted using the inverse model and compared to the known values. The results of the phantom verification show that this method is able to accurately extract top layer thickness and scattering when the top layer thickness ranges from 0 to 550 μm. In this range, top layer thicknesses were measured with an average error of 10% and the reduced scattering coefficient was measured with an average error of 15%. The accuracy of top and bottom layer absorption coefficient measurements was found to be highly dependent on top layer thickness, which agrees with physical expectation; however, within appropriate thickness ranges, the error for absorption properties varies from 12-25%. PMID:24466475

  17. Determining the Source of Water Vapor in a Cerium Oxide Electrochemical Oxygen Separator to Achieve Aviator Grade Oxygen

    Science.gov (United States)

    Graf, John; Taylor, Dale; Martinez, James

    2014-01-01

    ]. Combined with a mechanical compressor, a Solid Electrolyte Oxygen Separator (SEOS) should be capable of producing ABO grade oxygen at pressures >2400 psia, on the space station. Feasibility tests using a SEOS integrated with a mechanical compressor identified an unexpected contaminant in the oxygen: water vapour was found in the oxygen product, sometimes at concentrations higher than 40 ppm (the ABO limit for water vapour is 7 ppm). If solid electrolyte membranes are really "infinitely selective" to oxygen as they are reported to be, where did the water come from? If water is getting into the oxygen, what other contaminants might get into the oxygen? Microscopic analyses of wafers, welds, and oxygen delivery tubes were performed in an attempt to find the source of the water vapour contamination. Hot and cold pressure decay tests were performed. Measurements of water vapour as a function of O2 delivery rate, O2 delivery pressure, and process air humidity levels were the most instructive in finding the source of water contamination (Fig 3). Water contamination was directly affected by oxygen delivery rate (doubling the oxygen production rate cut the water level in half). Water was affected by process air humidity levels and delivery pressure in a way that indicates the water was diffusing into the oxygen delivery system.

  18. [Study of the effect of heat source separation distance on plasma physical properties in laser-pulsed GMAW hybrid welding based on spectral diagnosis technique].

    Science.gov (United States)

    Liao, Wei; Hua, Xue-Ming; Zhang, Wang; Li, Fang

    2014-05-01

    In the present paper, the authors calculated the plasma's peak electron temperatures under different heat source separation distance in laser- pulse GMAW hybrid welding based on Boltzmann spectrometry. Plasma's peak electron densities under the corresponding conditions were also calculated by using the Stark width of the plasma spectrum. Combined with high-speed photography, the effect of heat source separation distance on electron temperature and electron density was studied. The results show that with the increase in heat source separation distance, the electron temperatures and electron densities of laser plasma did not changed significantly. However, the electron temperatures of are plasma decreased, and the electron densities of are plasma first increased and then decreased. PMID:25095401

  19. Convolutive Blind Separation of DSSS Based on Characteristic Function and Matrix-*algebraic%基于特征函数和矩阵代数的卷积直扩信号分离

    Institute of Scientific and Technical Information of China (English)

    汤辉; 王殊

    2012-01-01

    针对多个直接序列扩频信号在多径信道传输后的卷积盲分离问题,提出了一个基于特征函数和矩阵代数的卷积盲分离方法.首先利用多传感器的条件,构建生成信号模型,且证明此模型符合独立子空间分析的基本条件;接着通过引入独立子空间分析的定义,证明直扩信号源的特征函数的Hessian矩阵满足块对角化性质;然后利用矩阵代数中矩阵分解的方法,将多个矩阵的联合块对角化问题转化为求取某个矩阵代数的可交换代数的一般性矩阵问题.当这个一般性矩阵被对角化时,卷积盲分离问题求解简化为求取一组齐次线性方程组的一个随机解.理论分析还表明,当噪声信号为高斯白噪声且具有相同的能量时,算法对于噪声具有非常强的鲁棒性.最后通过计算机仿真和与现有算法的比较,验证了新算法的有效性和可靠性,且具有更好的分离性能和相对更少的约束条件.新算法的不足之处是所需传感器数目较多,但在大规模传感器条件下能满足要求.%A method based on characteristic function and matrxi- * algebraic is proposed to solve the convolutive blind separation of Direct sequence spread spectrum signals through the multi-path channels. First, the signals model under the condition of multiple sensors is built and proved to be consistent with the basis of the Independent subspace analysis. Then the concept of independent subspace analysis is introduced, also the Hessian of Characteristic functions of the DSSS signals are proved to be block diagonal. Finally the matrix decomposition theory of matrix- *algebraic is used to transform the joint block diagonalization of multiple matries into the problem of finding a generic matrix of the commutant algebra, which is correspond to the matrix- *algebraic formed by the Hessian of Characteristic functions of the observed signals. And the diagonalization of the generic matrix is proved to be

  20. 一种改进的基于二阶统计量的盲源抽取算法%An Improved Blind Source Extraction Algorithm Based on Second Order Statistics

    Institute of Scientific and Technical Information of China (English)

    李飞; 李国林; 谢鑫

    2016-01-01

    针对之前盲源抽取算法存在鞍点的问题,提出一种新的基于二阶统计量的盲源抽取算法。通过利用自回归模型对抽取信号向量进行估计,并利用估计值与抽取向量之差提出一种新的代价函数,证明了代价函数的有效性。通过利用最速下降法对抽取向量以及FIR滤波器权值向量的计算,求解出抽取向量最优值。最后通过仿真证明算法相对之前两种算法有更高的可靠性,且在低信噪比的环境下,算法抽取效果依然良好且保持很高的抽取正确率。%In view of saddle points in blind source extraction algorithm before , an improved blind source extraction algorithm was proposed . Firstly, target signal vector was estimated by using autoregressive model , and a new cost function was proposed by using difference between the estimated vector and the extracted signal vector , effectiveness of new cost function was proved .The optimal solution of the extracted vector was computed by using the steepest descent method to extract vector and weight vector of FIR filter .At last, computer simulation proved that the improved algorithm shows higher reliability than the other two algorithms , and with better extraction effect and keeps higher accuracy in low SNR environment .

  1. Algebraic reconstruction combined with the signal space separation method for the inverse magnetoencephalography problem with a dipole-quadrupole source

    Science.gov (United States)

    Nara, T.; Koiwa, K.; Takagi, S.; Oyama, D.; Uehara, G.

    2014-05-01

    This paper presents an algebraic reconstruction method for dipole-quadrupole sources using magnetoencephalography data. Compared to the conventional methods with the equivalent current dipoles source model, our method can more accurately reconstruct two close, oppositely directed sources. Numerical simulations show that two sources on both sides of the longitudinal fissure of cerebrum are stably estimated. The method is verified using a quadrupolar source phantom, which is composed of two isosceles-triangle-coils with parallel bases.

  2. An application of the theory of planned behaviour to study the influencing factors of participation in source separation of food waste

    Energy Technology Data Exchange (ETDEWEB)

    Karim Ghani, Wan Azlina Wan Ab., E-mail: wanaz@eng.upm.edu.my [Department of Chemical and Environmental Engineering, Faculty of Engineering, University Putra Malaysia, 43400 Serdang, Selangor Darul Ehsan (Malaysia); Rusli, Iffah Farizan, E-mail: iffahrusli@yahoo.com [Department of Chemical and Environmental Engineering, Faculty of Engineering, University Putra Malaysia, 43400 Serdang, Selangor Darul Ehsan (Malaysia); Biak, Dayang Radiah Awang, E-mail: dayang@eng.upm.edu.my [Department of Chemical and Environmental Engineering, Faculty of Engineering, University Putra Malaysia, 43400 Serdang, Selangor Darul Ehsan (Malaysia); Idris, Azni, E-mail: azni@eng.upm.edu.my [Department of Chemical and Environmental Engineering, Faculty of Engineering, University Putra Malaysia, 43400 Serdang, Selangor Darul Ehsan (Malaysia)

    2013-05-15

    Highlights: ► Theory of planned behaviour (TPB) has been conducted to identify the influencing factors for participation in source separation of food waste using self administered questionnaires. ► The findings suggested several implications for the development and implementation of waste separation at home programme. ► The analysis indicates that the attitude towards waste separation is determined as the main predictors where this in turn could be a significant predictor of the repondent’s actual food waste separation behaviour. ► To date, none of similar have been reported elsewhere and this finding will be beneficial to local Authorities as indicator in designing campaigns to promote the use of waste separation programmes to reinforce the positive attitudes. - Abstract: Tremendous increases in biodegradable (food waste) generation significantly impact the local authorities, who are responsible to manage, treat and dispose of this waste. The process of separation of food waste at its generation source is identified as effective means in reducing the amount food waste sent to landfill and can be reused as feedstock to downstream treatment processes namely composting or anaerobic digestion. However, these efforts will only succeed with positive attitudes and highly participations rate by the public towards the scheme. Thus, the social survey (using questionnaires) to analyse public’s view and influencing factors towards participation in source separation of food waste in households based on the theory of planned behaviour technique (TPB) was performed in June and July 2011 among selected staff in Universiti Putra Malaysia, Serdang, Selangor. The survey demonstrates that the public has positive intention in participating provided the opportunities, facilities and knowledge on waste separation at source are adequately prepared by the respective local authorities. Furthermore, good moral values and situational factors such as storage convenience and

  3. An application of the theory of planned behaviour to study the influencing factors of participation in source separation of food waste

    International Nuclear Information System (INIS)

    Highlights: ► Theory of planned behaviour (TPB) has been conducted to identify the influencing factors for participation in source separation of food waste using self administered questionnaires. ► The findings suggested several implications for the development and implementation of waste separation at home programme. ► The analysis indicates that the attitude towards waste separation is determined as the main predictors where this in turn could be a significant predictor of the repondent’s actual food waste separation behaviour. ► To date, none of similar have been reported elsewhere and this finding will be beneficial to local Authorities as indicator in designing campaigns to promote the use of waste separation programmes to reinforce the positive attitudes. - Abstract: Tremendous increases in biodegradable (food waste) generation significantly impact the local authorities, who are responsible to manage, treat and dispose of this waste. The process of separation of food waste at its generation source is identified as effective means in reducing the amount food waste sent to landfill and can be reused as feedstock to downstream treatment processes namely composting or anaerobic digestion. However, these efforts will only succeed with positive attitudes and highly participations rate by the public towards the scheme. Thus, the social survey (using questionnaires) to analyse public’s view and influencing factors towards participation in source separation of food waste in households based on the theory of planned behaviour technique (TPB) was performed in June and July 2011 among selected staff in Universiti Putra Malaysia, Serdang, Selangor. The survey demonstrates that the public has positive intention in participating provided the opportunities, facilities and knowledge on waste separation at source are adequately prepared by the respective local authorities. Furthermore, good moral values and situational factors such as storage convenience and

  4. Simulations of cm-wavelength Sunyaev-Zel'dovich galaxy cluster and point source blind sky surveys and predictions for the RT32/OCRA-f and the Hevelius 100-m radio telescope

    Energy Technology Data Exchange (ETDEWEB)

    Lew, Bartosz; Kus, Andrzej [Toruń Centre for Astronomy, Nicolaus Copernicus University, ul. Gagarina 11, 87-100 Toruń (Poland); Birkinshaw, Mark [HH Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Wilkinson, Peter, E-mail: blew@astro.uni.torun.pl, E-mail: Mark.Birkinshaw@bristol.ac.uk, E-mail: peter.wilkinson@manchester.ac.uk, E-mail: ajk@astro.uni.torun.pl [Jodrell Bank Centre for Astrophysics, The University of Manchester, Alan Turing Building, Manchester M13 9PL (United Kingdom)

    2015-02-01

    We investigate the effectiveness of blind surveys for radio sources and galaxy cluster thermal Sunyaev-Zel'dovich effects (TSZEs) using the four-pair, beam-switched OCRA-f radiometer on the 32-m radio telescope in Poland. The predictions are based on mock maps that include the cosmic microwave background, TSZEs from hydrodynamical simulations of large scale structure formation, and unresolved radio sources. We validate the mock maps against observational data, and examine the limitations imposed by simplified physics. We estimate the effects of source clustering towards galaxy clusters from NVSS source counts around Planck-selected cluster candidates, and include appropriate correlations in our mock maps. The study allows us to quantify the effects of halo line-of-sight alignments, source confusion, and telescope angular resolution on the detections of TSZEs. We perform a similar analysis for the planned 100-m Hevelius radio telescope (RTH) equipped with a 49-beam radio camera and operating at frequencies up to 22 GHz.We find that RT32/OCRA-f will be suitable for small-field blind radio source surveys, and will detect 33{sup +17}{sub −11} new radio sources brighter than 0.87 mJy at 30 GHz in a 1 deg{sup 2} field at > 5σ CL during a one-year, non-continuous, observing campaign, taking account of Polish weather conditions. It is unlikely that any galaxy cluster will be detected at 3σ CL in such a survey. A 60-deg{sup 2} survey, with field coverage of 2{sup 2} beams per pixel, at 15 GHz with the RTH, would find <1.5 galaxy clusters per year brighter than 60 μJy (at 3σ CL), and would detect about 3.4 × 10{sup 4} point sources brighter than 1 mJy at 5σ CL, with confusion causing flux density errors ∼< 2% (20%) in 68% (95%) of the detected sources.A primary goal of the planned RTH will be a wide-area (π sr) radio source survey at 15 GHz. This survey will detect nearly 3 × 10{sup 5} radio sources at 5σ CL down to 1.3 mJy, and tens of galaxy

  5. An application of the theory of planned behaviour to study the influencing factors of participation in source separation of food waste.

    Science.gov (United States)

    Karim Ghani, Wan Azlina Wan Ab; Rusli, Iffah Farizan; Biak, Dayang Radiah Awang; Idris, Azni

    2013-05-01

    Tremendous increases in biodegradable (food waste) generation significantly impact the local authorities, who are responsible to manage, treat and dispose of this waste. The process of separation of food waste at its generation source is identified as effective means in reducing the amount food waste sent to landfill and can be reused as feedstock to downstream treatment processes namely composting or anaerobic digestion. However, these efforts will only succeed with positive attitudes and highly participations rate by the public towards the scheme. Thus, the social survey (using questionnaires) to analyse public's view and influencing factors towards participation in source separation of food waste in households based on the theory of planned behaviour technique (TPB) was performed in June and July 2011 among selected staff in Universiti Putra Malaysia, Serdang, Selangor. The survey demonstrates that the public has positive intention in participating provided the opportunities, facilities and knowledge on waste separation at source are adequately prepared by the respective local authorities. Furthermore, good moral values and situational factors such as storage convenience and collection times are also encouraged public's involvement and consequently, the participations rate. The findings from this study may provide useful indicator to the waste management authorities in Malaysia in identifying mechanisms for future development and implementation of food waste source separation activities in household programmes and communication campaign which advocate the use of these programmes. PMID:23415709

  6. An application of the theory of planned behaviour to study the influencing factors of participation in source separation of food waste.

    Science.gov (United States)

    Karim Ghani, Wan Azlina Wan Ab; Rusli, Iffah Farizan; Biak, Dayang Radiah Awang; Idris, Azni

    2013-05-01

    Tremendous increases in biodegradable (food waste) generation significantly impact the local authorities, who are responsible to manage, treat and dispose of this waste. The process of separation of food waste at its generation source is identified as effective means in reducing the amount food waste sent to landfill and can be reused as feedstock to downstream treatment processes namely composting or anaerobic digestion. However, these efforts will only succeed with positive attitudes and highly participations rate by the public towards the scheme. Thus, the social survey (using questionnaires) to analyse public's view and influencing factors towards participation in source separation of food waste in households based on the theory of planned behaviour technique (TPB) was performed in June and July 2011 among selected staff in Universiti Putra Malaysia, Serdang, Selangor. The survey demonstrates that the public has positive intention in participating provided the opportunities, facilities and knowledge on waste separation at source are adequately prepared by the respective local authorities. Furthermore, good moral values and situational factors such as storage convenience and collection times are also encouraged public's involvement and consequently, the participations rate. The findings from this study may provide useful indicator to the waste management authorities in Malaysia in identifying mechanisms for future development and implementation of food waste source separation activities in household programmes and communication campaign which advocate the use of these programmes.

  7. Facts About Color Blindness

    Science.gov (United States)

    ... quickly diagnose specific types of color blindness. The Ishihara Color Test is the most common test for red-green ... red-green color blindness. The newer Cambridge Color Test uses a visual array similar to the Ishihara plates, except displayed on a computer monitor. The ...

  8. Blindness%失明

    Institute of Scientific and Technical Information of China (English)

    李同良

    2009-01-01

    @@ There was a blind girl who hated herself because she was blind. She hated everyone,except her loving boyfriend who was always there for her. She told her boyfriend, "If I could only see the World, I will marry you."

  9. Blindness and Yoga

    Science.gov (United States)

    Heyes, Anthony David

    1974-01-01

    Evidence is presented to support the claims that, among many blind persons, physical inactivity leads to poor physical fitness; that a state of anxiety is often a concomitant of unguided blind mobility; and that Yogic practices offer a solution to both difficulties. (GW)

  10. Change blindness images.

    Science.gov (United States)

    Ma, Li-Qian; Xu, Kun; Wong, Tien-Tsin; Jiang, Bi-Ye; Hu, Shi-Min

    2013-11-01

    Change blindness refers to human inability to recognize large visual changes between images. In this paper, we present the first computational model of change blindness to quantify the degree of blindness between an image pair. It comprises a novel context-dependent saliency model and a measure of change, the former dependent on the site of the change, and the latter describing the amount of change. This saliency model in particular addresses the influence of background complexity, which plays an important role in the phenomenon of change blindness. Using the proposed computational model, we are able to synthesize changed images with desired degrees of blindness. User studies and comparisons to state-of-the-art saliency models demonstrate the effectiveness of our model. PMID:24029902

  11. Theoretical prediction of the source-detector separation distance suited to the application of the spatially resolved spectroscopy from the near-infrared attenuation data cube of tissues

    CERN Document Server

    Ri, Yong-Wu; Im, Song-Jin

    2014-01-01

    The modified Beer-Lambert law (MBL) and the spatially resolved spectroscopy are used to measure the tissue oxidation in muscles and brains by the continuous wave near-infrared spectroscopy. The spatially resolved spectroscopy predicts the change in the concentration of the absorber by measuring the slope of attenuation data according to the separation and calculating the absorption coefficients of tissue on the basis of the slop in attenuation at the separation distance satisfying the linearity of this slop. This study analyzed the appropriate source-detector separation distance by using the diffuse approximation resolution for photon migration when predicting the absorption coefficient by the spatially resolved spectroscopy on the basis of the reflective image of the tissue. We imagine the 3 dimensional attenuation image with the absorption coefficient, reduced scattering coefficient and separation distance as its axes and obtained the attenuation data cube by calculating the attenuation on a certain interva...

  12. Blinded by Irrelevance: Pure Irrelevance Induced "Blindness"

    Science.gov (United States)

    Eitam, Baruch; Yeshurun, Yaffa; Hassan, Kinneret

    2013-01-01

    To what degree does our representation of the immediate world depend solely on its relevance to what we are currently doing? We examined whether relevance per se can cause "blindness," even when there is no resource limitation. In a novel paradigm, people looked at a colored circle surrounded by a differently colored ring--the task relevance of…

  13. Residents’ Waste Separation Behaviors at the Source: Using SEM with the Theory of Planned Behavior in Guangzhou, China

    OpenAIRE

    Dongliang Zhang; Guangqing Huang; Xiaoling Yin; Qinghua Gong

    2015-01-01

    Understanding the factors that affect residents’ waste separation behaviors helps in constructing effective environmental campaigns for a community. Using the theory of planned behavior (TPB), this study examines factors associated with waste separation behaviors by analyzing responses to questionnaires distributed in Guangzhou, China. Data drawn from 208 of 1000-field questionnaires were used to assess socio-demographic factors and the TPB constructs (i.e., attitudes, subjective norms, perc...

  14. The blind hens’ challenge

    DEFF Research Database (Denmark)

    Sandøe, Peter; Hocking, Paul M.; Forkman, Björn;

    2014-01-01

    about breeding blind hens. But we also argue that alternative views, which (for example) claim that it is important to respect the telos or rights of an animal, do not offer a more convincing solution to questions raised by the possibility of disenhancing animals for their own benefit.......Animal ethicists have recently debated the ethical questions raised by disenhancing animals to improve their welfare. Here, we focus on the particular case of breeding blind hens for commercial egg-laying systems, in order to benefit their welfare. Many people find breeding blind hens intuitively...

  15. Blind Collective Signature Protocol

    Directory of Open Access Journals (Sweden)

    Nikolay A. Moldovyan

    2011-06-01

    Full Text Available Using the digital signature (DS scheme specified by Belarusian DS standard there are designed the collective and blind collective DS protocols. Signature formation is performed simultaneously by all of the assigned signers, therefore the proposed protocols can be used also as protocols for simultaneous signing a contract. The proposed blind collective DS protocol represents a particular implementation of the blind multisignature schemes that is a novel type of the signature schemes. The proposed protocols are the first implementations of the multisignature schemes based on Belarusian signature standard.

  16. Blind loop syndrome

    Science.gov (United States)

    ... operations for extreme obesity As a complication of inflammatory bowel disease Diseases such as diabetes or scleroderma may slow down movement in a segment of the intestine, leading to blind loop syndrome.

  17. A Blind Date

    Institute of Scientific and Technical Information of China (English)

    周立

    2003-01-01

    英语对话:A: Talking about girls, I still remember my first time to meet my girlfriend. Iwas so clumsy and very nervous.B: That’s the same case with me. I had the jitters at my blind date, too.A: Did you also meet your girlfriend at a blind date?B: Yeah. I was actually very shy of speaking to girls, you know?

  18. Development of an Ionization Scheme for Gold using the Selective Laser Ion Source at the On-Line Isotope Separator ISOLDE

    CERN Document Server

    Fedosseev, V; Marsh, B A; CERN. Geneva. AB Department

    2006-01-01

    At the ISOLDE on-line isotope separation facility, the resonance ionization laser ion source (RILIS) can be used to ionize reaction products as they effuse from the target. The RILIS process of laser step-wise resonance ionization of atoms in a hot metal cavity provides a highly element selective stage in the preparation of the radioactive ion beam. As a result, the ISOLDE mass separators can provide beams of a chosen isotope with greatly reduced isobaric contamination. The number of elements available at RILIS has been extended to 26, with the addition of a new three-step ionization scheme for gold. The optimal ionization scheme was determined during an extensive study of the atomic energy levels and auto-ionizing states of gold, carried out by means of in-source resonance ionization spectroscopy. Details of the ionization scheme and a summary of the spectroscopy study are presented.

  19. Blind Analysis in Particle Physics

    OpenAIRE

    Roodman, Aaron

    2003-01-01

    A review of the blind analysis technique, as used in particle physics measurements, is presented. The history of blind analyses in physics is briefly discussed. Next the dangers of "experimenter's bias" and the advantages of a blind analysis are described. Three distinct kinds of blind analysis in particle physics are presented in detail. Finally, the BABAR collaboration's experience with the blind analysis technique is discussed.

  20. Blind DOA estimation algorithm of coherent sources for conical conformal array antenna with respect to polarization diversity%锥面共形阵列天线相干信源盲极化DOA估计算法

    Institute of Scientific and Technical Information of China (English)

    齐子森; 郭英; 王布宏; 范海宁

    2011-01-01

    In view of the polarization diversity of conformal array antennas, the array manifold model for conical conformal array is established. With the help of special element arrangement, the spatial smoothing technology in conical conformal array antenna is developed, and the parameters pairing method of estimation of signal parameters via rotational invariance techniques (ESPRIT) is given when direction of arrival (DOA) of multiple sources are estimated. On this basis, a blind DOA estimation algorithm of coherent sources for conical conformal array antenna with respect to polarization diversity is proposed, and it realizes the high resolution DOA estimation of coherent sources using the singly curved surface of conical conformal carrier and the special requirement of ESPRIT algorithm.Monte-Carlo simulation results are provided to demonstrate the effectiveness and behavior of the proposed method%针对共形天线阵列流形的多极化特点,建立了锥面共形阵列天线导向矢量的数据模型.通过合理的阵元排列结构设计,推导了锥面共形阵列天线信源解相干的空间平滑算法,解决了ESPRIT(estimation of signalparameters via rotational invariance technique)算法多信源方位估计的参数配对问题,最终给出了锥面共形阵列天线相干信源盲极化波达方向(direction of arrival,DOA)估计算法.该算法利用锥面共形载体的单曲率特性,结合ESPRIT算法参数估计的特点,在盲极化条件下实现了相干信源的高分辨DOA估计.Monte Carlo仿真实验验证了算法的有效性.

  1. A source-depth separation filter: Using the Euler method on the derivatives of total intensity magnetic anomaly data

    Science.gov (United States)

    Ravat, D.; Kirkham, K.; Hildenbrand, T.G.

    2002-01-01

    An overview is given on the benefits of applying the Euler method on derivatives of anomalies to enhance the location of shallow and deep sources. Used properly, the method is suitable for characterizing sources from all potential-field data and/or their derivative, as long as the data can be regarded mathematically as "continuous". Furthermore, the reasons why the use of the Euler method on derivatives of anomalies is particularly helpful in the analysis and interpretation of shallow features are explained.

  2. Analysis of the separation of aquifers and potential shale gas source rocks: a national-scale screening study from the UK.

    Science.gov (United States)

    Bloomfield, John; Ward, Rob; Garcia-Bajo, Marieta; Hart, Alwyn

    2014-05-01

    A number of potential pathways can be identified for the migration of methane and contaminants associated with the shale gas extraction process to aquifers. These include the possible movement of contaminants from shale gas reservoirs that have been hydraulically fractured to overlying aquifers. The risk of contamination of an overlying aquifer is a function of i.) the separation of the potential shale gas source rock and the aquifer, ii.) the hydraulic characteristics (e.g. hydraulic conductivity, storage and hydrogeochemistry) of the rocks in the intervening interval, and iii.) regional and local physio-chemical gradients. Here we report on a national-scale study from the UK to assess the former, i.e. the vertical separation between potential shale gas source rocks and major aquifers, as a contribution to more informed management of the risks associated with shale gas development if and when it takes place in the UK. Eleven aquifers are considered in the study. These are aquifers that have been designated by the environment agencies of England (Environment Agency) and Wales (Natural Resources Wales) under the EU Water Framework Directive as being nationally important (Principal Aquifers). The shale gas source rocks have been defined on best publically available evidence for potential gas productivity and include both shales and clay formations. Based on a national geological fence diagram consisting of ~80 geological sections, totalling ~12,000km in length, down to >5km in depth, and with a typical spacing of 30km, the lower surfaces of each aquifer unit and upper surfaces of each shale/clay unit have been estimated at a spatial resolution of 3x3km. These surfaces have then been used to estimate vertical separations between pairs of shale/clay and aquifer units. The modelling process will be described and the aquifer, shale and separation maps presented and discussed. The aquifers are defined by geological units and since these geological units may be found at

  3. Research on Receiving Technology Based on Blind Signal Separation for Satellite MIMO Communication System%基于盲分离的卫星MIMO系统接收技术研究

    Institute of Scientific and Technical Information of China (English)

    辛吉荣; 万坚; 陈绍贺; 程建

    2013-01-01

    针对卫星MIMO(Multi-Input Multi-Output)通信系统,提出采用盲分离的思路对各卫星信号进行接收.考虑到盲分离性能易受噪声、混合矩阵病态性的影响,分析了噪声对接收性能影响最小时信道传输矩阵(即盲分离中的混合矩阵)应满足的条件,并给出了满足此条件的等距线阵的构建方式.通过计算机仿真分析了在此方式下,等距线阵的方位角、间距以及信号频率对盲分离接收的影响,最后得出对天线阵列建设具有一定指导意义的结论,为进一步进行实验奠定基础.%Methods of using blind signal processing was proposed to receive the communication signal in Satellite MIMO (Multi-Input Multi-Output) system. Since the receiving performance was affected by noise and illness of mixing matrix, the channel transfer matrix (also called mixing matrix in blind signal processing) that minimized the noise affection was analyzed. The relationship between the transfer matrix and the uniform linear array's parameter such as azimuth angle, distance between two adjacent antennas and the frequency was also analyzed by simulation. Final, some conclusions useful in designing an antenna array in satellite communication system were given out.

  4. Investigation of source-detector separation optimization for an implantable perfusion and oxygenation sensor for liver blood vessels

    Energy Technology Data Exchange (ETDEWEB)

    Baba, Justin S [ORNL; Akl, Tony [Texas A& M University; Cote, Gerard L. [Texas A& M University; Wilson, Mark A. [University of Pittsburgh School of Medicine, Pittsburgh PA; Ericson, Milton Nance [ORNL

    2011-01-01

    An implanted system is being developed to monitor transplanted liver health during the critical 7-10 day period posttransplantation. The unit will monitor organ perfusion and oxygen consumption using optically-based probes placed on both the inflow and outflow blood vessels, and on the liver parenchymal surface. Sensing probes are based on a 3- wavelength LED source and a photodiode detector. Sample diffuse reflectance is measured at 735, 805, and 940 nm. To ascertain optimal source-to-photodetector spacing for perfusion measurement in blood vessels, an ex vivo study was conducted. In this work, a dye mixture simulating 80% blood oxygen saturation was developed and perfused through excised porcine arteries while collecting data for various preset probe source-to-photodetector spacings. The results from this study demonstrate a decrease in the optical signal with decreasing LED drive current and a reduction in perfusion index signal with increasing probe spacing. They also reveal a 2- to 4-mm optimal range for blood vessel perfusion probe source-to-photodetector spacing that allows for sufficient perfusion signal modulation depth with maximized signal to noise ratio (SNR). These findings are currently being applied to guide electronic configuration and probe placement for in vivo liver perfusion porcine model studies.

  5. A Maximum Likelihood Estimation of Vocal-Tract-Related Filter Characteristics for Single Channel Speech Separation

    Directory of Open Access Journals (Sweden)

    Mohammad H. Radfar

    2006-11-01

    Full Text Available We present a new technique for separating two speech signals from a single recording. The proposed method bridges the gap between underdetermined blind source separation techniques and those techniques that model the human auditory system, that is, computational auditory scene analysis (CASA. For this purpose, we decompose the speech signal into the excitation signal and the vocal-tract-related filter and then estimate the components from the mixed speech using a hybrid model. We first express the probability density function (PDF of the mixed speech's log spectral vectors in terms of the PDFs of the underlying speech signal's vocal-tract-related filters. Then, the mean vectors of PDFs of the vocal-tract-related filters are obtained using a maximum likelihood estimator given the mixed signal. Finally, the estimated vocal-tract-related filters along with the extracted fundamental frequencies are used to reconstruct estimates of the individual speech signals. The proposed technique effectively adds vocal-tract-related filter characteristics as a new cue to CASA models using a new grouping technique based on an underdetermined blind source separation. We compare our model with both an underdetermined blind source separation and a CASA method. The experimental results show that our model outperforms both techniques in terms of SNR improvement and the percentage of crosstalk suppression.

  6. A Maximum Likelihood Estimation of Vocal-Tract-Related Filter Characteristics for Single Channel Speech Separation

    Directory of Open Access Journals (Sweden)

    Dansereau Richard M

    2007-01-01

    Full Text Available We present a new technique for separating two speech signals from a single recording. The proposed method bridges the gap between underdetermined blind source separation techniques and those techniques that model the human auditory system, that is, computational auditory scene analysis (CASA. For this purpose, we decompose the speech signal into the excitation signal and the vocal-tract-related filter and then estimate the components from the mixed speech using a hybrid model. We first express the probability density function (PDF of the mixed speech's log spectral vectors in terms of the PDFs of the underlying speech signal's vocal-tract-related filters. Then, the mean vectors of PDFs of the vocal-tract-related filters are obtained using a maximum likelihood estimator given the mixed signal. Finally, the estimated vocal-tract-related filters along with the extracted fundamental frequencies are used to reconstruct estimates of the individual speech signals. The proposed technique effectively adds vocal-tract-related filter characteristics as a new cue to CASA models using a new grouping technique based on an underdetermined blind source separation. We compare our model with both an underdetermined blind source separation and a CASA method. The experimental results show that our model outperforms both techniques in terms of SNR improvement and the percentage of crosstalk suppression.

  7. Separation and quantification of frequency coupled noise sources of submarine cabin%舱段模型频率耦合噪声源的分离量化

    Institute of Scientific and Technical Information of China (English)

    李思纯; 宫元彬; 时胜国; 于树华; 韩闯

    2016-01-01

    Traditional methods do not effectively handle separation and quantification of coupled vibration noise sources in submarines. So a new multivariate statistical analysis method, partial least square regression ( PLS) , is presented, which can be used to separate and quantify frequency coupled noise sources. PLS has the characteristic of simultaneously extracting principal input/output components, including maximum information, correlation of in⁃put with output, and regression modeling with multiple correlations among variables. Simulation and cabin model experiments show that, when there is frequency coupling between multiple excitation sources, PLS is capable of sorting among the energy contributions of internal noise sources to submarine hull, submarine hull to underwater a⁃coustic field, and noise sources to underwater acoustic field. The feasibility of PLS for frequency coupled source separation and quantification is proven. The method provides a basis for the control of the main noise sources.%由于潜艇振动噪声源存在频率相互耦合现象,常规方法难以有效地解决耦合噪声源分离与贡献量化问题。采用一种新型多元统计分析方法-偏最小二乘回归分析方法来实现频率耦合噪声源的分离量化,该方法可同时提取反映输入/输出中最大信息且相关性最大的主成分,并能够在变量间存在多重相关性的条件下进行回归建模。仿真与舱段模型试验表明:当多激励源之间存在频率耦合时,能对噪声源进行分离和贡献量化,从而实现了噪声源对耐压壳体观测点贡献以及噪声源对辐射声场观测点贡献的排序,验证了偏最小二乘回归用于频率耦合源分离量化的可行性,为主要噪声源的控制提供了依据。

  8. Orientation-dependent phase separation of GaAsSb epilayers grown by gas-source molecular-beam epitaxy

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yi-Ren; Chou, Li-Chang; Yang, Ying-Jay [Graduate Institute of Electronics Engineering, National Taiwan University, Taipei 10617, Taiwan (China); Lin, Hao-Hsiung, E-mail: hhlin@ntu.edu.tw [Graduate Institute of Electronics Engineering, National Taiwan University, Taipei 10617, Taiwan (China); Department of Electrical Engineering and Graduate Institute of Photonics and Optoelectronics, National Taiwan University, Taipei 10617, Taiwan (China)

    2012-04-30

    This work describes a regular solution model that considers the free energy of the surface monolayer to explain the orientation-dependent phase separation in GaAsSb. In the proposed model, only the interaction between the second nearest-neighboring atoms sitting on the same monolayer contributes to the interaction parameter. Consequently, the parameter reduces to {Omega}/2 and {Omega}/3 for (111)B GaAsSb and (100) GaAsSb, where {Omega} denotes the parameter of bulk GaAsSb. By including the strain effect, the proposed model thoroughly elucidates the immiscibility behavior of (111)B GaAsSb and (100) GaAsSb. - Highlights: Black-Right-Pointing-Pointer (111)B GaAsSb exhibits severe phase separation than (100) GaAsSb. Black-Right-Pointing-Pointer We propose a model to calculate the monolayer free energy of different planes. Black-Right-Pointing-Pointer Monolayer model suggests that (111)B GaAsSb has larger interaction parameter. Black-Right-Pointing-Pointer Monolayer model including strain well explains the immiscibility of GaAsSb.

  9. Methods for estimation of the number of sources in blind source separation%盲信号分离中信号源数目估计方法研究

    Institute of Scientific and Technical Information of China (English)

    徐小红; 高隽; 范之国

    2008-01-01

    研究盲信号分离中信号源数目未知情况下信号源数目的估计问题.证明了无观测噪声时,利用观察信号数据矩阵的零空间估计法确定信号源数目的方法,等价于通过计算观察信号数据矩阵的秩来确定信号源数目;阐述了在信号源盲分离中有观测噪声时,国内外信号源数目估计的主要方法:特征值分解、Akaike信息准则(AIC)、最小描述长度(MDL)及Minka Bayesian准则,通过理论分析与实验结果对这些方法进行比较,得出各方法的适用范围以及影响估计的主要参数,为信号源数目的正确获取提供参考.

  10. Performance of Daylight Redirecting Venetian Blinds for Sidelighted Spaces at High Latitudes

    OpenAIRE

    Kolås, Tore

    2013-01-01

    The main topic of this thesis is daylight in buildings. More specifically, the thesis presents studies on the performance characteristics of venetian blinds used on the interior side of vertical windows. A particular emphasis is put on the daylighting properties of different blind types, and the performance of daylight redirecting blinds is compared to the performance of traditional white blinds.Three factors are highly important for daylight in buildings: the daylight source, the optical pro...

  11. Models for the Blind

    OpenAIRE

    Jan Eric Olsén

    2014-01-01

    When displayed in museum cabinets, tactile objects that were once used in the education of blind and visually impaired people, appear to us, sighted visitors, as anything but tactile. We cannot touch them due to museum policies and we can hardly imagine what it would have been like for a blind person to touch them in their historical context. And yet these objects are all about touch, from the concrete act of touching something to the norms that assigned touch a specific pedagogical role in n...

  12. BLIND EQUALIZATION OF MIMO SYSTEMS BASED ON ORTHOGONAL CONSTANT MODULUS ALGORITHM

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    This paper investigates adaptive blind source separation and equalization for Multiple Input Mul-tiple Output (MIMO) systems. To effectively recover input signals, remove Inter-Symbol Interference (ISI)and suppress Inter-User Interference (IUI), the array input is first transformed into the signal subspace, thenwith the derived orthogonality between weight vectors of different input signals, a new orthogonal ConstantModulus Algorithm (CMA) is proposed. Computer simulation results illustrate the promising performance ofthe proposed method. Without channel identification, the proposed method can recover all the system inputssimultaneously and can be adaptive to channel changes without prior knowledge about signals.

  13. Change blindness: eradication of gestalt strategies

    OpenAIRE

    Wilson, Steve; Goddard, Paul

    2011-01-01

    Arrays of eight, texture-defined rectangles were used as stimuli in a one-shot change blindness (CB) task where there was a 50% chance that one rectangle would change orientation between two successive presentations separated by an interval. CB was eliminated by cueing the target rectangle in the first stimulus, reduced by cueing in the interval and unaffected by cueing in the second presentation. This supports the idea that a representation was formed that persisted through the interval befo...

  14. Recent developments in production of radioactive ion beams with the selective laser ion source at the on-line isotope separator ISOLDE

    International Nuclear Information System (INIS)

    The resonance ionization laser ion source (RILIS) of the ISOLDE on-line isotope separation facility is based on the method of laser stepwise resonance ionization of atoms in a hot metal cavity. The atomic selectivity of the RILIS compliments the mass selection process of the ISOLDE separator magnets to provide beams of a chosen isotope with greatly reduced isobaric contamination. Using a system of dye lasers pumped by copper vapor lasers, ion beams of 22 elements have been generated at ISOLDE with ionization efficiencies in the range of 0.5%-30%. As part of the ongoing RILIS development, recent off-line resonance ionization spectroscopy studies have determined the optimal three-step ionization schemes for yttrium, scandium, and antimony

  15. Recent developments in production of radioactive ion beams with the selective laser ion source at the on-line isotope separator ISOLDE

    Science.gov (United States)

    Catherall, R.; Fedosseev, V. N.; Köster, U.; Lettry, J.; Suberlucq, G.; Marsh, B. A.; Tengborn, E.

    2004-05-01

    The resonance ionization laser ion source (RILIS) of the ISOLDE on-line isotope separation facility is based on the method of laser stepwise resonance ionization of atoms in a hot metal cavity. The atomic selectivity of the RILIS compliments the mass selection process of the ISOLDE separator magnets to provide beams of a chosen isotope with greatly reduced isobaric contamination. Using a system of dye lasers pumped by copper vapor lasers, ion beams of 22 elements have been generated at ISOLDE with ionization efficiencies in the range of 0.5%-30%. As part of the ongoing RILIS development, recent off-line resonance ionization spectroscopy studies have determined the optimal three-step ionization schemes for yttrium, scandium, and antimony.

  16. In Situ Electrostatic Separation of Ambient PM2.5 into Source-Specific Fractions During Collection in a FRM Sampler

    Energy Technology Data Exchange (ETDEWEB)

    Naresh Shah; Frank E. Huggins; Gerald P. Huffman

    2006-07-31

    Coal combustion is generally viewed as a major source of PM2.5 emissions into the atmosphere. For some time, toxicologists have been asking for an exposure environment enriched with the coal combustion source specific PM{sub 2.5} to conduct meaningful exposure studies to better understand the mechanisms of the adverse health effects of coal combustion specific PM2.5 in the ambient environment. There are several unique characteristics of primary PM generated from coal combustion. In this research project, an attempt has been made to exploit some of the unique properties of PM generated from coal fired power plants to preferentially separate them out from the rest of the primary and secondary PM in the ambient environment. An existing FRM sampler used for monitoring amount of PM{sub 2.5} in the ambient air is modified to incorporate an electrostatic field. A DC corona charging device is also installed at the ambient air inlet to impart positive or negative charge to the PM. Visual Basic software has been written to simulate the lateral movement of PM as it passes through the electrostatic separator under varying operating conditions. The PM samples collected on polycarbonate filters under varying operating conditions were extensively observed for clustering and/or separation of PM in the direction parallel to the electric field. No systematic PM separation was observed under any of the operating conditions. A solution to overcome this kind of turbulence caused remixing has been offered. However, due to major programmatic changes in the DOE UCR program, there are no venues available to further pursue this research.

  17. High-visibility two-photon interference at a telecom wavelength using picosecond-regime separated sources

    International Nuclear Information System (INIS)

    We report on a two-photon interference experiment in a quantum relay configuration using two picosecond regime periodically poled lithium niobate (PPLN) waveguide based sources emitting paired photons at 1550 nm. The results show that the picosecond regime associated with a guided-wave scheme should have important repercussions for quantum relay implementations in real conditions, essential for improving both the working distance and the efficiency of quantum cryptography and networking systems. In contrast to already reported regimes, namely, femtosecond and CW, it allows achieving a 99% net visibility two-photon interference while maintaining a high effective photon pair rate using only standard telecom components and detectors.

  18. Modeling of the charge-state separation at ITEP experimental facility for material science based on a Bernas ion source

    International Nuclear Information System (INIS)

    The experiment automation system is supposed to be developed for experimental facility for material science at ITEP, based on a Bernas ion source. The program CAMFT is assumed to be involved into the program of the experiment automation. CAMFT is developed to simulate the intense charged particle bunch motion in the external magnetic fields with arbitrary geometry by means of the accurate solution of the particle motion equation. Program allows the consideration of the bunch intensity up to 1010 ppb. Preliminary calculations are performed at ITEP supercomputer. The results of the simulation of the beam pre-acceleration and following turn in magnetic field are presented for different initial conditions

  19. Modeling of the charge-state separation at ITEP experimental facility for material science based on a Bernas ion source

    Energy Technology Data Exchange (ETDEWEB)

    Barminova, H. Y., E-mail: barminova@bk.ru; Saratovskyh, M. S. [National Research Nuclear University MEPhI, Kashirskoye sh. 31, Moscow 115409 (Russian Federation)

    2016-02-15

    The experiment automation system is supposed to be developed for experimental facility for material science at ITEP, based on a Bernas ion source. The program CAMFT is assumed to be involved into the program of the experiment automation. CAMFT is developed to simulate the intense charged particle bunch motion in the external magnetic fields with arbitrary geometry by means of the accurate solution of the particle motion equation. Program allows the consideration of the bunch intensity up to 10{sup 10} ppb. Preliminary calculations are performed at ITEP supercomputer. The results of the simulation of the beam pre-acceleration and following turn in magnetic field are presented for different initial conditions.

  20. Recent developments in production of radioactive ion beams with the selective laser ion source at the on-line isotope separator ISOLDE

    CERN Document Server

    Catherall, Richard; Köster, U; Lettry, Jacques; Suberlucq, Guy; Marsh, Bruce A; Tengborn, Elisabeth

    2004-01-01

    The production of radioactive ionization laser ion source (RILIS) of ISOLDE on-line isotope separation facility was investigated. The RILIS setup included three dye lasers and ionization schemes which employ three resonant transitions were also used. The RILIS efficiency could be reduced by nuclear effects such as hyperfine splitting and isotope shifts. The off-line resonance ionization spectroscopy determined optimal three-step ionization schemes for yttrium, scandium and antimony and antimony. The results show that best ionization schemes of Y provided gain factor of 15 with respect to surface ionization. (Edited abstract) 8 Refs.

  1. Radiochemical Separation and Measurement by Mass Spectrometry with Magnetic Sector with Inductively Coupled Plasma source (ICP-SFMS of Plutonium Isotopes in Soil Samples

    Directory of Open Access Journals (Sweden)

    C. O. Torres-Cortés

    2016-08-01

    Full Text Available The aim of this work is twofold: to optimize the radiochemical separation of Plutonium (Pu from soil samples, and to measure the Pu concentration. Soil samples were prepared using acid digestion assisted by microwaves; then, Pu purification was carried out with Pu AG1X8 resin. Pu isotopes were measured using Mass Spectrometry with Magnetic Sector with Inductively Coupled Plasma source (ICP-SFMS. In order to reduce the interference due to the presence of 238UH+ in the samples a desolvation system (Apex was used. The limit of detection (LOD of Pu was determined. The efficiency of Pu recovery from soil samples varies from 70 to 93%.

  2. Testing Children for Color Blindness

    Science.gov (United States)

    ... Español Eye Health / News Testing Children for Color Blindness Written by: Shirley Dang Apr. 03, 2014 New ... shows that kids can be tested for color blindness as soon as age 4, finds Caucasian boys ...

  3. Oplysningens blinde vinkler

    DEFF Research Database (Denmark)

    Hansen, Pelle Guldborg; Hendricks, Vincent Fella

    manipulation og fordrejning, til at påvirke menneskers overvejelser, beslutninger og handlinger, både individuelt og kollektivt, hvilket i sidste ende kan få betydning for de demokratiske processer. Oplysningens blinde vinkler gennemgår en række informationsfænomener, som optræder i vores dagligdag, og den...

  4. Oplysnigens blinde vinkler

    DEFF Research Database (Denmark)

    Hendricks, Vincent Fella; Hansen, Pelle Guldborg

    manipulation og fordrejning, til at påvirke menneskers overvejelser, beslutninger og handlinger, både individuelt og kollektivt, hvilket i sidste ende kan få betydning for de demokratiske processer. Oplysningens blinde vinkler gennemgår en række informationsfænomener, som optræder i vores dagligdag, og den...

  5. Magnetic Separation in Romania

    OpenAIRE

    Rezlescu, Nicolae; Bradu, Elena-Brandusa; Iacob, Gheorghe; Badescu, Vasile; Iacob, Lavinia

    1986-01-01

    The utilization of the magnetic separators of foreign and Romanian source is presented and the most important achievements in research, engineering design and manufacturing activity concerning the magnetic separation in Romania are reviewed.

  6. Corneal blindness and xenotransplantation.

    Science.gov (United States)

    Lamm, Vladimir; Hara, Hidetaka; Mammen, Alex; Dhaliwal, Deepinder; Cooper, David K C

    2014-01-01

    Approximately 39 million people are blind worldwide, with an estimated 285 million visually impaired. The developing world shoulders 90% of the world's blindness, with 80% of causative diseases being preventable or treatable. Blindness has a major detrimental impact on the patient, community, and healthcare spending. Corneal diseases are significant causes of blindness, affecting at least 4 million people worldwide. The prevalence of corneal disease varies between parts of the world. Trachoma, for instance, is the second leading cause of blindness in Africa, after cataracts, but is rarely found today in developed nations. When preventive strategies have failed, corneal transplantation is the most effective treatment for advanced corneal disease. The major surgical techniques for corneal transplantation include penetrating keratoplasty (PK), anterior lamellar keratoplasty, and endothelial keratoplasty (EK). Indications for corneal transplantation vary between countries, with Fuchs' dystrophy being the leading indication in the USA and keratoconus in Australia. With the exception of the USA, where EK will soon overtake PK as the most common surgical procedure, PK is the overwhelming procedure of choice. Success using corneal grafts in developing nations, such as Nepal, demonstrates the feasibility of corneal transplantation on a global scale. The number of suitable corneas from deceased human donors that becomes available will never be sufficient, and so research into various alternatives, for example stem cells, amniotic membrane transplantation, synthetic and biosynthetic corneas, and xenotransplantation, is progressing. While each of these has potential, we suggest that xenotransplantation holds the greatest potential for a corneal replacement. With the increasing availability of genetically engineered pigs, pig corneas may alleviate the global shortage of corneas in the near future.

  7. sources

    Directory of Open Access Journals (Sweden)

    Shu-Yin Chiang

    2002-01-01

    Full Text Available In this paper, we study the simplified models of the ATM (Asynchronous Transfer Mode multiplexer network with Bernoulli random traffic sources. Based on the model, the performance measures are analyzed by the different output service schemes.

  8. IMPROVED COVARIANCE DRIVEN BLIND SUBSPACE IDENTIFICATION METHOD

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhiyi; FAN Jiangling; HUA Hongxing

    2006-01-01

    An improved covariance driven subspace identification method is presented to identify the weakly excited modes. In this method, the traditional Hankel matrix is replaced by a reformed one to enhance the identifiability of weak characteristics. The robustness of eigenparameter estimation to noise contamination is reinforced by the improved Hankel matrix. In combination with component energy index (CEI) which indicates the vibration intensity of signal components, an alternative stabilization diagram is adopted to effectively separate spurious and physical modes. Simulation of a vibration system of multiple-degree-of-freedom and experiment of a frame structure subject to wind excitation are presented to demonstrate the improvement of the proposed blind method. The performance of this blind method is assessed in terms of its capability in extracting the weak modes as well as the accuracy of estimated parameters. The results have shown that the proposed blind method gives a better estimation of the weak modes from response signals of small signal to noise ratio (SNR)and gives a reliable separation of spurious and physical estimates.

  9. Application of independent component analysis for speech-music separation using an efficient score function estimation

    Science.gov (United States)

    Pishravian, Arash; Aghabozorgi Sahaf, Masoud Reza

    2012-12-01

    In this paper speech-music separation using Blind Source Separation is discussed. The separating algorithm is based on the mutual information minimization where the natural gradient algorithm is used for minimization. In order to do that, score function estimation from observation signals (combination of speech and music) samples is needed. The accuracy and the speed of the mentioned estimation will affect on the quality of the separated signals and the processing time of the algorithm. The score function estimation in the presented algorithm is based on Gaussian mixture based kernel density estimation method. The experimental results of the presented algorithm on the speech-music separation and comparing to the separating algorithm which is based on the Minimum Mean Square Error estimator, indicate that it can cause better performance and less processing time

  10. Sources

    OpenAIRE

    2015-01-01

    Sources Fondation Pablo Iglesias. Alcala de Henares. Sections : Archives privées de Manuel ArijaArchives extérieuresArchives FNJS de EspañaPrensa Archives Générales de l’Administration. Alcala de Henares. Sections : Opposition au franquismeSig. 653 Sig TOP 82/68.103-68.602.Índice de las cartas colectivas, Relaciones, Cartas al Ministro de Información de Marzo de 1965. c.662. Sources cinématographiques Filmothèque Nationale d’Espagne.NO.DO. N° 1157C. 08/03/1965.aguirre Javier, Blanco vertical....

  11. Stochastic Blind Motion Deblurring

    KAUST Repository

    Xiao, Lei

    2015-05-13

    Blind motion deblurring from a single image is a highly under-constrained problem with many degenerate solutions. A good approximation of the intrinsic image can therefore only be obtained with the help of prior information in the form of (often non-convex) regularization terms for both the intrinsic image and the kernel. While the best choice of image priors is still a topic of ongoing investigation, this research is made more complicated by the fact that historically each new prior requires the development of a custom optimization method. In this paper, we develop a stochastic optimization method for blind deconvolution. Since this stochastic solver does not require the explicit computation of the gradient of the objective function and uses only efficient local evaluation of the objective, new priors can be implemented and tested very quickly. We demonstrate that this framework, in combination with different image priors produces results with PSNR values that match or exceed the results obtained by much more complex state-of-the-art blind motion deblurring algorithms.

  12. Blind Stereoscopy of the Coronal Magnetic Field

    CERN Document Server

    Aschwanden, Markus J; Malanushenko, Anna

    2015-01-01

    We test the feasibility of 3D coronal-loop tracing in stereoscopic EUV image pairs, with the ultimate goal of enabling efficient 3D reconstruction of the coronal magnetic field that drives flares and coronal mass ejections (CMEs). We developed an automated code designed to perform triangulation of coronal loops in pairs (or triplets) of EUV images recorded from different perspectives. The automated (or blind) stereoscopy code includes three major tasks: (i) automated pattern recognition of coronal loops in EUV images, (ii) automated pairing of corresponding loop patterns from two different aspect angles, and (iii) stereoscopic triangulation of 3D loop coordinates. We perform tests with simulated stereoscopic EUV images and quantify the accuracy of all three procedures. In addition we test the performance of the blind stereoscopy code as a function of the spacecraft-separation angle and as a function of the spatial resolution. We also test the sensitivity to magnetic non-potentiality. The automated code develo...

  13. Performance Comparison Research of the FECG Signal Separation Based on the BSS Algorithm

    Directory of Open Access Journals (Sweden)

    Xinling Wen

    2012-08-01

    Full Text Available Fetal Electrocardiogram (FECG is a weak signal through placing the electrodes upon the maternal belly surface to indirectly monitor, which contains all the forms of jamming signal. So, how to separate the FECG from the strong background interference has important value of clinical application. Independent Component Analysis (ICA is a kind of developed new Blind Source Separation (BSS technology in recent years. This study adopted ICA method to the extraction of FECG and carried out the blind signal separation by using the Fast ICA algorithm and natural gradient algorithm in the FECG separation research. The experimental results shown that the two kind of algorithm can obtain the good separation result. But because the natural gradient algorithm can achieve FECG online separation and separation effect is better than Fast ICA algorithm, therefore, the natural gradient algorithm is a better way to used in FECG separation. And it will help to monitor the congenital heart disease, neonatal arrhythmia, intrauterine fetal retardation and other diseases, which has very important test application value.

  14. Event-related potentials reveal rapid registration of features of infrequent changes during change blindness

    OpenAIRE

    Astikainen Piia; Wikgren Jan; Lyyra Pessi

    2010-01-01

    Abstract Background Change blindness refers to a failure to detect changes between consecutively presented images separated by, for example, a brief blank screen. As an explanation of change blindness, it has been suggested that our representations of the environment are sparse outside focal attention and even that changed features may not be represented at all. In order to find electrophysiological evidence of neural representations of changed features during change blindness, we recorded ev...

  15. Three sources and three components of success in detection of ultra-rare alpha decays at the Dubna Gas-Filled Recoil separator

    CERN Document Server

    Tsyganov, Y S

    2015-01-01

    General philosophy of procedure of detecting rare events in the recent experiments with 48Ca projectile at the Dubna Gas-Filled Recoil Separator(DGFRS) aimed to the synthesis of superheavy elements (SHE) has been reviewed. Specific instruments and methods are under consideration. Some historical sources of the successful experiments for Z=112-118 are considered too. Special attention is paid to application of method of active correlations in heavy-ion induced complete fusion nuclear reactions. Example of application in Z=115 experiment is presented. Brief description of the 243Am + 48Ca -> 291-x115+xn experiment is presented too. Some attention is paid to the role of chemical experiments in discoveries of SHEs. The DGFRS detection/monitoring system is presented in full firstly.

  16. Isotope-based hydrograph separation in large rivers: assessing flow sources and water quality controls in the oil sands region, Canada

    Science.gov (United States)

    Gibson, John; Yi, Yi; Birks, Jean

    2016-04-01

    Hydrograph separation using stable isotopes of water is used to partition streamflow sources in the Athabasca River and its tributaries in the oil sands region of northern Alberta, Canada. Snow, rain, groundwater and surface water contributions to total streamflow are estimated for multi-year records and provide considerable insight into runoff generation mechanisms operating in six tributaries and at four stations along the Athabasca River. Groundwater, found to be an important flow source at all stations, is the dominant component of the hydrograph in three tributaries (Steepbank R., Muskeg R., Firebag R.), accounting for 39 to 50% of annual streamflow. Surface water, mainly drainage from peatlands, is also found to be widely important, and dominant in three tributaries (Clearwater R., Mackay R., Ells R.), accounting for 45 to 81% of annual streamflow. Direct runoff of precipitation sources including rain (7-19%) and snowmelt (3-7%) account for the remainder of sources. Fairly limited contributions from direct precipitation illustrate that most snow and rain events result in indirect displacement of pre-event water (surface water and groundwater), due in part to the prevalence of fill and spill mechanisms and limited overland flow. Systematic shifts in the groundwater:surface-water ratios, noted for the main stem of the Athabasca River and in its tributaries, is an important control on the spatial and temporal distribution of major and minor ions, trace elements, dissolved organics and contaminants, as well as for evaluating the susceptibility of the rivers to climate and development-related impacts. Runoff partitioning is likely to be a useful monitoring tool for better understanding of flow drivers and water quality controls, and for determining the underlying causes of climate or industrial impacts.

  17. MCMC joint separation and segmentation of hidden Markov fields

    CERN Document Server

    Snoussi, H; Snoussi, Hichem; Mohammad-Djafari, Ali

    2002-01-01

    In this contribution, we consider the problem of the blind separation of noisy instantaneously mixed images. The images are modelized by hidden Markov fields with unknown parameters. Given the observed images, we give a Bayesian formulation and we propose to solve the resulting data augmentation problem by implementing a Monte Carlo Markov Chain (MCMC) procedure. We separate the unknown variables into two categories: 1. The parameters of interest which are the mixing matrix, the noise covariance and the parameters of the sources distributions. 2. The hidden variables which are the unobserved sources and the unobserved pixels classification labels. The proposed algorithm provides in the stationary regime samples drawn from the posterior distributions of all the variables involved in the problem leading to a flexibility in the cost function choice. We discuss and characterize some problems of non identifiability and degeneracies of the parameters likelihood and the behavior of the MCMC algorithm in this case. F...

  18. Study of the feasibility of distributed cathodic arc as a plasma source for development of the technology for plasma separation of SNF and radioactive wastes

    Science.gov (United States)

    Amirov, R. Kh.; Vorona, N. A.; Gavrikov, A. V.; Liziakin, G. D.; Polistchook, V. P.; Samoylov, I. S.; Smirnov, V. P.; Usmanov, R. A.; Yartsev, I. M.

    2015-12-01

    One of the key problems in the development of plasma separation technology is designing a plasma source which uses condensed spent nuclear fuel (SNF) or nuclear wastes as a raw material. This paper covers the experimental study of the evaporation and ionization of model materials (gadolinium, niobium oxide, and titanium oxide). For these purposes, a vacuum arc with a heated cathode on the studied material was initiated and its parameters in different regimes were studied. During the experiment, the cathode temperature, arc current, arc voltage, and plasma radiation spectra were measured, and also probe measurements were carried out. It was found that the increase in the cathode heating power leads to the decrease in the arc voltage (to 3 V). This fact makes it possible to reduce the electron energy and achieve singly ionized plasma with a high degree of ionization to fulfill one of the requirements for plasma separation of SNF. This finding is supported by the analysis of the plasma radiation spectrum and the results of the probe diagnostics.

  19. Study of the feasibility of distributed cathodic arc as a plasma source for development of the technology for plasma separation of SNF and radioactive wastes

    Energy Technology Data Exchange (ETDEWEB)

    Amirov, R. Kh.; Vorona, N. A.; Gavrikov, A. V.; Liziakin, G. D.; Polistchook, V. P.; Samoylov, I. S.; Smirnov, V. P.; Usmanov, R. A., E-mail: ravus46@yandex.ru; Yartsev, I. M. [Russian Academy of Sciences, Joint Institute for High Temperatures (Russian Federation)

    2015-12-15

    One of the key problems in the development of plasma separation technology is designing a plasma source which uses condensed spent nuclear fuel (SNF) or nuclear wastes as a raw material. This paper covers the experimental study of the evaporation and ionization of model materials (gadolinium, niobium oxide, and titanium oxide). For these purposes, a vacuum arc with a heated cathode on the studied material was initiated and its parameters in different regimes were studied. During the experiment, the cathode temperature, arc current, arc voltage, and plasma radiation spectra were measured, and also probe measurements were carried out. It was found that the increase in the cathode heating power leads to the decrease in the arc voltage (to 3 V). This fact makes it possible to reduce the electron energy and achieve singly ionized plasma with a high degree of ionization to fulfill one of the requirements for plasma separation of SNF. This finding is supported by the analysis of the plasma radiation spectrum and the results of the probe diagnostics.

  20. Study of the feasibility of distributed cathodic arc as a plasma source for development of the technology for plasma separation of SNF and radioactive wastes

    International Nuclear Information System (INIS)

    One of the key problems in the development of plasma separation technology is designing a plasma source which uses condensed spent nuclear fuel (SNF) or nuclear wastes as a raw material. This paper covers the experimental study of the evaporation and ionization of model materials (gadolinium, niobium oxide, and titanium oxide). For these purposes, a vacuum arc with a heated cathode on the studied material was initiated and its parameters in different regimes were studied. During the experiment, the cathode temperature, arc current, arc voltage, and plasma radiation spectra were measured, and also probe measurements were carried out. It was found that the increase in the cathode heating power leads to the decrease in the arc voltage (to 3 V). This fact makes it possible to reduce the electron energy and achieve singly ionized plasma with a high degree of ionization to fulfill one of the requirements for plasma separation of SNF. This finding is supported by the analysis of the plasma radiation spectrum and the results of the probe diagnostics

  1. Fate of 17β-Estradiol as a model estrogen in source separated urine during integrated chemical P recovery and treatment using partial nitritation-anammox process.

    Science.gov (United States)

    Huang, Pei; Mukherji, Sachiyo T; Wu, Sha; Muller, James; Goel, Ramesh

    2016-10-15

    Recently, research on source separation followed by the treatment of urine and/or resource recovery from human urine has shown promise as an emerging management strategy. Despite contributing only 1% of the total volume of wastewater, human urine contributes about 80% of the nitrogen, 70% of the potassium, and up to 50% of the total phosphorus in wastewater. It is also a known fact that many of the micropollutants, especially selected estrogens, get into municipal wastewater through urine excretion. In this research, we investigated the fate of 17β-estradiol (E2) as a model estrogen during struvite precipitation from synthetic urine followed by the treatment of urine using a partial nitritation-anammox (PN/A) system. Single-stage and two-stage suspended growth PN/A configurations were used to remove the nitrogen in urine after struvite precipitation. The results showed an almost 95% phosphorous and 5% nitrogen recovery/removal from the synthetic urine due to struvite precipitation. The single and two stage PN/A processes were able to remove around 50% and 75% of ammonia and nitrogen present in the post struvite urine solution, respectively. After struvite precipitation, more than 95% of the E2 remained in solution and the transformation of E2 to E1 happened during urine storage. Most of the E2 removal that occurred during the PN/A process was due to sorption on the biomass and biodegradation (transformation of E2 to E1, and slow degradation of E1 to other metabolites). These results demonstrate that a combination of chemical and biological unit processes will be needed to recover and manage nutrients in source separated urine. PMID:27566951

  2. [Aiming for zero blindness].

    Science.gov (United States)

    Nakazawa, Toru

    2015-03-01

    Glaucoma is the leading cause of acquired blindness in Japan. One reason that it often leads to blindness is that it can continue to worsen even after effective medical reduction of intraocular pressure (IOP), the only evidence-based treatment. The limitations of current treatments make it critical to identify IOP-independent factors that can cause glaucoma and develop new drugs to target these factors. This is a challenging task, as the pathology of glaucoma is thought to be very complex, with different combinations of factors underlying its development and progression in different patients. Additionally, there is a deficiency in methods to efficiently perform clinical evaluations and reliably probe the state of the disease over relatively short periods. In addition, newly developed drugs need to be evaluated with clinical trials, for which human and financial resources are limited, before they can be widely used for treatment. Taking all these issues into consideration, it is evident that there are two urgent issues to consider: the development of methods to classify glaucoma in detail based on its pathology, and the improvement of clinical evaluation methods. In this review, we discuss some of our efforts to develop new neuroprotective agents for glaucoma, with a focus on the following three areas: 1. Clinical research and development of methods to classify glaucoma in detail based on IOP-independent factors, and the exploration of possibilities for the improvement of clinical evaluation of glaucoma. 2. Pathology-based research and development of new drugs for glaucoma, focusing on comprehensive gene expression analysis and the development of molecule-targeting drugs, using murine optic nerve crush as a disease model. 3. Development of next generation in vivo imaging modalities and the establishment of infrastructure enabling "big-data" analysis. First, we discuss our clinical research and the development of methods to classify glaucoma in detail based on IOP

  3. Noise blind test

    OpenAIRE

    H. Cadet

    2006-01-01

    In the aim of characterizing site condition for seismic risk, the microtremor or ambient noise studies have been developed. The main objective of this blind test is to check of the reliability of results, to observe the user subjectivity (array choice, parameters that are user depend) in the noise recordings analyze. Noise records were analysed on single-station with H/V method and with several sensors for array method to determine the dispersion characteristics of the surface-wave part of th...

  4. FLIPPS for the Blind

    DEFF Research Database (Denmark)

    Bothe, Hans-Heinrich; Al-Hamdani, Sermed

    2010-01-01

    The idea of FLIPPS is to design, implement, and evaluate a vibro-tactile device that is composed of a photo diode, vibro-tactile stimulator, microcontroller and power supply. The stimulator is attached to the finger tip and activated when light illumination exceeds a defined threshold. The subject...... (blind person) receives the reflected light from the objects and, based on brain plasticity principles, can interactively learn to construct a mental image of the objects and of the scenery. The FLIPPS idea is based on sensory substitution theory; here, substituting visual inputs by haptic vibrations....

  5. A Novel Constrained Topographic Independent Component Analysis for Separation of Epileptic Seizure Signals

    Directory of Open Access Journals (Sweden)

    Min Jing

    2007-01-01

    Full Text Available Blind separation of the electroencephalogram signals (EEGs using topographic independent component analysis (TICA is an effective tool to group the geometrically nearby source signals. The TICA algorithm further improves the results if the desired signal sources have particular properties which can be exploited in the separation process as constraints. Here, the spatial-frequency information of the seizure signals is used to design a constrained TICA for the separation of epileptic seizure signal sources from the multichannel EEGs. The performance is compared with those from the TICA and other conventional ICA algorithms. The superiority of the new constrained TICA has been validated in terms of signal-to-interference ratio and correlation measurement.

  6. 基于线性混合盲分离模型的电机故障诊断方法%Fault diagnosis method of motor based on linear mixing blind separation model

    Institute of Scientific and Technical Information of China (English)

    侯新国; 李彧; 向东阳; 杨忠林; 卜乐平

    2014-01-01

    基于定子电流信号的频谱分析方法诊断电机故障,其检测的精度易受到噪声干扰及频率分辨率的限制。为解决这一问题,提出了一种基于线性混合盲分离模型的电机故障诊断方法。该方法采用固定点算法从电机的定子电流信号中分离出故障特征信号,由观测信号估计出混合矩阵,据此计算故障特征信号的幅值,再根据幅值在电机正常和故障状态下的变化实现对电机故障的诊断。以电机转子故障为例进行了实验,结果表明:该方法可实现转子断条故障的可靠诊断,并且在短数据条件下,也能取得较好的诊断效果。%T he detection precision of fault diagnosis based on the frequency spectral analysis of stator current is easily restricted by noise jamming and frequency resolution .To solve this problem ,this pa-per proposes a fault diagnosis method of induction motor based on the linear mixing model .The method uses the Fast-ICA algorithm to separate the fault characteristic signal from the motor stator current . The amplitude of the signal is calculated with the mixing matrix estimated by the observed signal .The fault diagnosis can be made according to the amplitude varying in a normal state and a fault state of the motor .With the diagnosis of faults in the broken rotor bars as an example ,the experiment result shows that the algorithm can well diagnose the broken-rotor-bar fault ,and also achieve a good result in the condition of short data block .

  7. The whole story behind blind adaptive equalizers/blind deconvolution

    CERN Document Server

    Pinchas, Monika

    2012-01-01

    This e-book covers a variety of blind deconvolution/equalization methods based on both cost functions and Bayes rules where simulation results are supplied to support the theory - including Maximum Entropy density approximation technique and the Edgeworth Expansion approach used in various blind equalizers.

  8. POSTERIOR SEGMENT CAUSES OF BLINDNESS AMONG CHILDREN IN BLIND SCHOOLS

    Directory of Open Access Journals (Sweden)

    Sandhya

    2015-09-01

    Full Text Available BACKGROUND: It is estimated that there are 1.4 million irreversibly blind children in the world out of which 1 million are in Asia alone. India has the highest number of blind children than any other country. Nearly 70% of the childhood blindness is avoidable. There i s paucity of data available on the causes of childhood blindness. This study focuses on the posterior segment causes of blindness among children attending blind schools in 3 adjacent districts of Andhra Pradesh. MATERIAL & METHODS: This is a cross sectiona l study conducted among 204 blind children aged 6 - 16 years age. Detailed eye examination was done by the same investigator to avoid bias. Posterior segment examination was done using a direct and/or indirect ophthalmoscope after dilating pupil wherever nec essary. The standard WHO/PBL for blindness and low vision examination protocol was used to categorize the causes of blindness. A major anatomical site and underlying cause was selected for each child. The study was carried out during July 2014 to June 2015 . The results were analyzed using MS excel software and Epi - info 7 software version statistical software. RESULTS: Majority of the children was found to be aged 13 - 16 years (45.1% and males (63.7%. Family history of blindness was noted in 26.0% and consa nguinity was reported in 29.9% cases. A majority of them were belonged to fulfill WHO grade of blindness (73.0% and in majority of the cases, the onset of blindness was since birth (83.7%. The etiology of blindness was unknown in majority of cases (57.4% while hereditary causes constituted 25.4% cases. Posterior segment causes were responsible in 33.3% cases with retina being the most commonly involved anatomical site (19.1% followed by optic nerve (14.2%. CONCLUSIONS: There is a need for mandatory oph thalmic evaluation, refraction and assessment of low vision prior to admission into blind schools with periodic evaluation every 2 - 3 years

  9. Autobiographic narratives of congenital blind people

    Directory of Open Access Journals (Sweden)

    Maria Elisa Caputo Ferreira

    2009-12-01

    Full Text Available The research carried out in Juiz de Fora, MG, Brazil, intended at investigating, together with men and women who suffer from congenital visual impairment, how they felt about diversity, body image, self-esteem and vanity. The investigation of autobiographical accounts was the option for this study. Initially, 20 (twenty interviews were analyzed and 6 (six autobiographical accounts, selected from the peculiarities of each single interviewee – each one containing his/her single life lessons - followed suit. The conclusion reached is that the subjects had undergone an exhausting process of acceptance of their own impairment. If, on the one hand, the blindness comes with angst, uncertainties, and many difficulties, on the other hand, these circumstances lead the blind to face the ups and downs of life with courage, determination and will to live. Surprisingly, in the study the body was not approached at a source of concern or are which should be emphasized.

  10. Separation of uncompromised whole blood mixtures for single source STR profiling using fluorescently-labeled human leukocyte antigen (HLA) probes and fluorescence activated cell sorting (FACS).

    Science.gov (United States)

    Dean, Lee; Kwon, Ye Jin; Philpott, M Katherine; Stanciu, Cristina E; Seashols-Williams, Sarah J; Dawson Cruz, Tracey; Sturgill, Jamie; Ehrhardt, Christopher J

    2015-07-01

    Analysis of biological mixtures is a significant problem for forensic laboratories, particularly when the mixture contains only one cell type. Contributions from multiple individuals to biologic evidence can complicate DNA profile interpretation and often lead to a reduction in the probative value of DNA evidence or worse, its total loss. To address this, we have utilized an analytical technique that exploits the intrinsic immunological variation among individuals to physically separate cells from different sources in a mixture prior to DNA profiling. Specifically, we applied a fluorescently labeled antibody probe to selectively bind to one contributor in a mixture through allele-specific interactions with human leukocyte antigen (HLA) proteins that are expressed on the surfaces of most nucleated cells. Once the contributor's cells were bound to the probe, they were isolated from the mixture using fluorescence activated cell sorting (FACS)-a high throughput technique for separating cell populations based on their optical properties-and then subjected to STR analysis. We tested this approach on two-person and four-person whole blood mixtures where one contributor possessed an HLA allele (A*02) that was not shared by other contributors to the mixture. Results showed that hybridization of the mixture with a fluorescently-labeled antibody probe complimentary to the A*02 allele's protein product created a cell population with a distinct optical profile that could be easily differentiated from other cells in the mixture. After sorting the cells with FACS, genetic analysis showed that the STR profile of this cell population was consistent with that of the contributor who possessed the A*02 allele. Minor peaks from the A*02 negative contributor(s) were observed but could be easily distinguished from the profile generated from A*02 positive cells. Overall, this indicates that HLA antibody probes coupled to FACS may be an effective approach for generating STR profiles of

  11. Overview on Deaf-Blindness

    Science.gov (United States)

    Miles, Barbara

    2008-01-01

    It may seem that deaf-blindness refers to a total inability to see or hear. However, in reality deaf-blindness is a condition in which the combination of hearing and visual losses in children cause "such severe communication and other develop mental and educational needs that they cannot be accommodated in special education programs solely for…

  12. National Center On Deaf-Blindness

    Science.gov (United States)

    ... My Profile Logout Menu NCDB: National Center on Deaf-Blindness NCDB: National Center on Deaf-Blindness Help ... Collaborate Project Staff Service Provider Family Member State Deaf-Blind Projects Click on a state on the ...

  13. Multi-channel blind deconvolution algorithm for multiple-input multiple-output DS/CDMA system

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Direct sequence spread spectrum transmission can be realized at low SNR,and has low probability of detection.It is aly problem how to obtain the original users'signal in a non-cooperative context.In practicality,the DS/CDMA sources received are linear convolute mixing.A more complex multichannel blind deconvolution MBD algorithm is required to achieve better source separation.An improved MBD algorithm for separating linear convolved mixtures of signals in CDMA system is proposed.This algorithm is based on minimizing the average squared cross-output-channel-correlation.The mixture coefficients are totally unknown.while some knowledge about temporal model exists.Results show that the proposed algorithm Can bring about the exactness and low computational complexity.

  14. Blind Known Interference Cancellation

    CERN Document Server

    Zhang, Shengli; Wang, Hui

    2011-01-01

    This paper investigates interference-cancellation schemes at the receiver, in which the original data of the interference is known a priori. Such a priori knowledge is common in wireless relay networks. For example, a transmitting relay could be relaying data that was previously transmitted by a node, in which case the interference received by the node now is actually self information. Besides the case of self information, the node could also have overheard or received the interference data in a prior transmission by another node. Directly removing the known interference requires accurate estimate of the interference channel, which may be difficult in many situations. In this paper, we propose a novel scheme, Blind Known Interference Cancellation (BKIC), to cancel known interference without interference channel information. BKIC consists of two steps. The first step combines adjacent symbols to cancel the interference, exploiting the fact that the channel coefficients are almost the same between successive sy...

  15. Evaluation of a novel noncontact spectrally and spatially resolved reflectance setup with continuously variable source-detector separation using silicone phantoms.

    Science.gov (United States)

    Andree, Stefan; Reble, Carina; Helfmann, Jurgen; Gersonde, Ingo; Illing, Gerd

    2010-01-01

    We present a new variant of a noncontact, oblique incidence spatially resolved reflectance setup. The continuously variable source detector separation enables adaptation to high and low albedo samples. Absorption (μ(a)) and reduced scattering coefficients (μ(') (s)) are determined in the wavelength range of 400-1000 nm using a lookup table, calculated by a Monte Carlo simulation of the light transport. The method is characterized by an silicone phantom study covering a wide parameter range 0.01 mm(-1) ≤ μ(a) ≤ 2.5 mm(-1) and 0.2 mm(-1) ≤ μ(') (s) ≤ 10 mm(-1), which includes the optical parameters of tissue in the visible and near infrared. The influence of the incident angle and the detection aperture on the simulated remission was examined. Using perpendicular incidence and 90-deg detection aperture in the Monte Carlo simulation in contrast to the experimental situation with 30-deg incidence and 4.6-deg detection aperture is shown to be valid for the parameter range μ(') (s) > 1 mm(-1) and μ(a) coefficient for increasing absorption can be the consequence of real physics instead of cross talk. PMID:21198213

  16. A Completely Blind Video Integrity Oracle.

    Science.gov (United States)

    Mittal, Anish; Saad, Michele A; Bovik, Alan C

    2016-01-01

    Considerable progress has been made toward developing still picture perceptual quality analyzers that do not require any reference picture and that are not trained on human opinion scores of distorted images. However, there do not yet exist any such completely blind video quality assessment (VQA) models. Here, we attempt to bridge this gap by developing a new VQA model called the video intrinsic integrity and distortion evaluation oracle (VIIDEO). The new model does not require the use of any additional information other than the video being quality evaluated. VIIDEO embodies models of intrinsic statistical regularities that are observed in natural vidoes, which are used to quantify disturbances introduced due to distortions. An algorithm derived from the VIIDEO model is thereby able to predict the quality of distorted videos without any external knowledge about the pristine source, anticipated distortions, or human judgments of video quality. Even with such a paucity of information, we are able to show that the VIIDEO algorithm performs much better than the legacy full reference quality measure MSE on the LIVE VQA database and delivers performance comparable with a leading human judgment trained blind VQA model. We believe that the VIIDEO algorithm is a significant step toward making real-time monitoring of completely blind video quality possible. PMID:26599970

  17. The willed blindness of humans

    DEFF Research Database (Denmark)

    Gjerris, Mickey

    2012-01-01

    This paper describes how we seem to live in a willed blindness towards the effects that our meat production and consumption have on animals, the environment and the climate. It is a willed blindness that cannot be explained by either lack of knowledge or scientific uncertainty. The blindness...... enables us to see ourselves as moral beings although our lack of reaction to the effects of our actions tells another story. The consequences, especially to animal welfare are outlined and it is briefly discussed whether a solution lies in a new moral vision of our obligations or a new vision of what...

  18. The 2007 National Federation of the Blind Youth Slam: Making Astronomy Accessible to Students Who are Blind

    Science.gov (United States)

    Grice, Noreen A.

    2008-05-01

    In the summer of 2007, nearly two hundred blind and visually impaired high school students participated in a weeklong enrichment program at Johns Hopkins University called the National Federation of the Blind Youth Slam. They spent four days participating in hands-on science and engineering classes and exploring careers previously thought inaccessible to those without sight. The students were separated into "tracks” with each group focusing on a different field. Want to know what happened in the astronomy track? Come by this paper and see examples of accessible astronomy activities, including accessible star parties, from the Youth Slam!

  19. Blind Search for Variability in Planck Data

    CERN Document Server

    Rachen, Jörg P; Reinecke, Martin

    2015-01-01

    The sky is full of variable and transient sources on all time scales, from milliseconds to decades. Planck's regular scanning strategy makes it an ideal instrument to search for variable sky signals in the millimetre and submillimetre regime, on time scales from hours to several years. A precondition is that instrumental noise and systematic effects, caused in particular by non-symmetric beam shapes, are properly removed. We present a method to perform a full sky blind search for variable and transient objects at all Planck frequencies.

  20. Ultracapacitor separator

    Science.gov (United States)

    Wei, Chang; Jerabek, Elihu Calvin; LeBlanc, Jr., Oliver Harris

    2001-03-06

    An ultracapacitor includes two solid, nonporous current collectors, two porous electrodes separating the collectors, a porous separator between the electrodes and an electrolyte occupying the pores in the electrodes and separator. The electrolyte is a polar aprotic organic solvent and a salt. The porous separator comprises a wet laid cellulosic material.

  1. LOVE IS COLOR BLIND

    Institute of Scientific and Technical Information of China (English)

    陈梦扬

    2013-01-01

    <正>看完这部电影,突然想起小时候看完《辛德勒的名单》后,问过母亲一个问题:"为什么有些人要嘲笑和歧视那些与众不同的人?"母亲告诉我:"我们都是一样的,没有人应当受到责备,每个人都应当为自己而活,要始终坚信‘Love is color blind(爱无定界)’。"爱究竟有无定界?有太多故事让我们相信这句话并非纸上谈兵。《汤姆叔叔的小屋》、《美国往事》、《为黛西小姐开车》……是的,"Love"是"Listen(倾听)",是无条件无偏见地倾听对方的需求,并予以协助;是"Obligate(感恩)",需要不断地感恩,付出爱来灌

  2. Co-located monogenetic eruptions ~200 kyr apart driven by tapping vertically separated mantle source regions, Chagwido, Jeju Island, Republic of Korea

    Science.gov (United States)

    Brenna, Marco; Németh, Károly; Cronin, Shane J.; Sohn, Young Kwan; Smith, Ian E. M.; Wijbrans, Jan

    2015-05-01

    New eruptions in monogenetic volcanic fields conceptually occur independently of previous ones. In some instances, however, younger volcanic structures and vents may overlap with older edifices. The genetic links between such co-located eruptions remain unclear. We mapped and analysed the stratigraphic relationships between eruptive units on the 400 × 900-m island of Chagwido off the western coast of Jeju Island, a Pleistocene to Holocene intraplate volcanic field. Chagwido consists of an eastern, older tuff ring with a nested scoria cone and a western tuff, scoria and lava flow sequence. The two stratigraphic packages are separated by a prominent paleosol. The East-Chagwido tuff and scoria deposits were eroded and a period of intense weathering and soil development occurred, before a subsequent West-Chagwido tuff ring and scoria cone and lava complex was erupted. The two eruptions were fed by three chemically distinct magmas. The older eastern eruption consists of magma with composition transitional between high-Al alkalic basalt and low-Al alkalic basalt and has stratigraphic characteristics, composition and syn-eruptive trends akin to the neighbouring Dangsanbong tuff cone. This magma type is typical for the transitional stage from high-Al alkalic (pre 500 ka) to low-Al alkalic (post 250 ka) identified for the greater Jeju volcanic system. The East-Chagwido volcanic complex thus formed as the westernmost in a chain of three volcanoes along a fissure system, with a small volcanic remnant island Wado 1 km to the east and the large Dangsanbong tuff cone another 1 km eastward. A new Ar/Ar age of 446 ± 22 ka for Dangsanbong likely characterizes the age of the whole chain. The second, West-Chagwido eruption started with low-Al alkalic basalt forming a phreatomagmatic phase and ended with subalkalic basalt forming a scoria cone and lava flows. The occurrence of subalkalic lavas is known across Jeju to have started only at ~250 ka, and thus, the well

  3. Simplified solar optical calculations for windows with venetian blinds

    Energy Technology Data Exchange (ETDEWEB)

    Kotey, N.A.; Wright, J.L. [Waterloo Univ., ON (Canada). Dept. of Mechanical Engineering

    2006-07-01

    Solar gain through a window represents the largest and most variable heat gain imposed on an indoor space. The potential for shading devices to optimize the energy efficiency of buildings was discussed with reference to the value of modeling complex fenestration system in annual energy simulation programs. Shading devices such as venetian blinds, roller blinds and drapes are commonly used to control solar gain through windows. In this paper, three sets of calculations were presented for a window with light and dark coloured venetian blinds using simplified models and computational procedures. Hourly transmitted, reflected and absorbed fluxes were calculated for both summer and winter conditions with a venetian blind placed on the indoor-side of the window; a venetian blind placed between the glazings; and, a venetian blind placed on the outdoor-side of the window. As the first step in energy analysis of the complex fenestration systems, short-wave radiation models determine the fraction of incident solar radiation directly transmitted through the complex fenestration system and the fraction that is absorbed in each layer. The absorbed solar energy in each layer serves as a source term for the heat transfer analysis. In this study, simplified models were used to calculate the transmitted, reflected and absorbed fluxes of solar radiation for windows with venetian blinds. The study showed that a particular configuration of a window with a venetian blind can significantly influence the amount of energy transmitted to the indoor space at different times of the year. In addition, the slat angle could reduce the building energy requirements during the summer and winter seasons. The simplified calculation procedures produced results that can serve as useful input to building load and annual energy calculation tools. 9 refs., 2 tabs., 10 figs.

  4. Laboratory Techniques for the Blind

    Science.gov (United States)

    Tombaugh, Dorothy

    1972-01-01

    Describes modifications of laboratory procedures for the BSCS Green Version biology, including dissection, microbiology, animal behavior, physiology, biochemistry, and genetics that make the methods suitable for direct experimentation by blind students. Discusses models as substitutes for microscopy. (AL)

  5. Student Art for Blind Children.

    Science.gov (United States)

    Vanda, Kay

    1982-01-01

    Describes a project in which high school student volunteers designed art activities for blind children. Students incorporated the sensation of motion and texture into their designs for toys, puzzles, games, and story illustrations. (AM)

  6. American Foundation for the Blind

    Science.gov (United States)

    ... celebrate and support a workforce that is fully inclusive of people who are blind or visually impaired. 5 great ways to celebrate National Disability Employment Awareness Month College Bound? Transitioning to college and ...

  7. Blinded trials taken to the test

    DEFF Research Database (Denmark)

    Hróbjartsson, A; Forfang, E; Haahr, M T;

    2007-01-01

    Blinding can reduce bias in randomized clinical trials, but blinding procedures may be unsuccessful. Our aim was to assess how often randomized clinical trials test the success of blinding, the methods involved and how often blinding is reported as being successful....

  8. What It's Like to Be Color Blind

    Science.gov (United States)

    ... Homework? Here's Help White House Lunch Recipes What It's Like to Be Color Blind KidsHealth > For Kids > What It's Like to Be Color Blind Print A A ... blind. But some people really are color blind. It doesn't mean they can't see any ...

  9. Blinding measured: a systematic review of randomized controlled trials of acupuncture.

    Science.gov (United States)

    Moroz, Alex; Freed, Brian; Tiedemann, Laura; Bang, Heejung; Howell, Melanie; Park, Jongbae J

    2013-01-01

    Background. There is no agreement among researchers on viable controls for acupuncture treatment, and the assessment of the effectiveness of blinding and its interpretation is rare. Purpose. To systematically assess the effectiveness of blinding (EOB) in reported acupuncture trials; to explore results of RCTs using a quantitative measure of EOB. Data Sources. A systematic review of published sham RCTs that assessed blinding. Study Selection. Five hundred and ninety studies were reviewed, and 54 studies (4783 subjects) were included. Data Extraction. The number of patients who guessed their treatment identity was extracted from each study. Variables with possible influence on blinding were identified. Data Synthesis. The blinding index was calculated for each study. Based on blinding indexes, studies were congregated into one of the nine blinding scenarios. Individual study characteristics were explored for potential association with EOB. Limitations. There is a possibility of publication or reporting bias. Conclusions. The most common scenario was that the subjects believed they received verum acupuncture regardless of the actual treatment received, and overall the subject blinding in the acupuncture studies was satisfactory, with 61% of study participants maintaining ideal blinding. Objectively calculated blinding data may offer meaningful and systematic ways to further interpret the findings of RCTs.

  10. Using acoustic information to perceive room size: effects of blindness, room reverberation time, and stimulus.

    Science.gov (United States)

    Kolarik, Andrew J; Pardhan, Shahina; Cirstea, Silvia; Moore, Brian C J

    2013-01-01

    Blind participants greatly rely on sound for spatial information regarding the surrounding environment. It is not yet established whether lack of vision to calibrate audition in far space affects blind participants' internal spatial representation of acoustic room size. Furthermore, blind participants may rely more on farthest distance estimates to sound sources compared with sighted participants when perceiving room size. Here we show that judgments of apparent room size and sound distance are correlated, more so for blind than for sighted participants. Sighted participants judged a reverberant virtual room to be larger for speech than for music or noise stimuli, whereas blind participants did not. The results suggest that blindness affects the use of room reverberation for distance and room-size judgments. PMID:24386717

  11. On the blind recovery of cardiac and respiratory sounds

    DEFF Research Database (Denmark)

    Shah, Ghafoor; Koch, Peter; Papadias, Constantinos B.

    2015-01-01

    We present a method for smart auscultation by proposing a novel blind recovery of the original cardiac and respiratory sounds from a single observation mixture, in the framework of non-negative matrix factorization (NMF). The method learns the basis spectra of the mixing sources in unsupervised...

  12. Multiframe Blind Super Resolution Imaging Based on Blind Deconvolution

    Institute of Scientific and Technical Information of China (English)

    元伟; 张立毅

    2016-01-01

    As an ill-posed problem, multiframe blind super resolution imaging recovers a high resolution image from a group of low resolution images with some degradations when the information of blur kernel is limited. Note that the quality of the recovered image is influenced more by the accuracy of blur estimation than an advanced regularization. We study the traditional model of the multiframe super resolution and modify it for blind deblurring. Based on the analysis, we proposed two algorithms. The first one is based on the total variation blind deconvolution algorithm and formulated as a functional for optimization with the regularization of blur. Based on the alternating minimization and the gradient descent algorithm, the high resolution image and the unknown blur kernel are esti-mated iteratively. By using the median shift and add operator, the second algorithm is more robust to the outlier influence. The MSAA initialization simplifies the interpolation process to reconstruct the blurred high resolution image for blind deblurring and improves the accuracy of blind super resolution imaging. The experimental results demonstrate the superiority and accuracy of our novel algorithms.

  13. The global cost of eliminating avoidable blindness

    Directory of Open Access Journals (Sweden)

    Kirsten L Armstrong

    2012-01-01

    Full Text Available Aims : To complete an initial estimate of the global cost of eliminating avoidable blindness, including the investment required to build ongoing primary and secondary health care systems, as well as to eliminate the ′backlog′ of avoidable blindness. This analysis also seeks to understand and articulate where key data limitations lie. Materials and Methods : Data were collected in line with a global estimation approach, including separate costing frameworks for the primary and secondary care sectors, and the treatment of backlog. Results : The global direct health cost to eliminate avoidable blindness over a 10-year period from 2011 to 2020 is estimated at $632 billion per year (2009 US$. As countries already spend $592 billion per annum on eye health, this represents additional investment of $397.8 billion over 10 years, which is $40 billion per year or $5.80 per person for each year between 2010 and 2020. This is concentrated in high-income nations, which require 68% of the investment but comprise 16% of the world′s inhabitants. For all other regions, the additional investment required is $127 billion. Conclusions : This costing estimate has identified that low- and middle-income countries require less than half the additional investment compared with high-income nations. Low- and middle-income countries comprise the greater investment proportion in secondary care whereas high-income countries require the majority of investment into the primary sector. However, there is a need to improve sector data. Investment in better data will have positive flow-on effects for the eye health sector.

  14. 20 CFR 416.983 - How we evaluate statutory blindness.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false How we evaluate statutory blindness. 416.983... AGED, BLIND, AND DISABLED Determining Disability and Blindness Blindness § 416.983 How we evaluate statutory blindness. We will find that you are blind if you are statutorily blind within the meaning...

  15. 20 CFR 416.982 - Blindness under a State plan.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Blindness under a State plan. 416.982 Section..., BLIND, AND DISABLED Determining Disability and Blindness Blindness § 416.982 Blindness under a State... plan because of your blindness for the month of December 1973; and (c) You continue to be blind...

  16. [Aiming for zero blindness].

    Science.gov (United States)

    Nakazawa, Toru

    2015-03-01

    Glaucoma is the leading cause of acquired blindness in Japan. One reason that it often leads to blindness is that it can continue to worsen even after effective medical reduction of intraocular pressure (IOP), the only evidence-based treatment. The limitations of current treatments make it critical to identify IOP-independent factors that can cause glaucoma and develop new drugs to target these factors. This is a challenging task, as the pathology of glaucoma is thought to be very complex, with different combinations of factors underlying its development and progression in different patients. Additionally, there is a deficiency in methods to efficiently perform clinical evaluations and reliably probe the state of the disease over relatively short periods. In addition, newly developed drugs need to be evaluated with clinical trials, for which human and financial resources are limited, before they can be widely used for treatment. Taking all these issues into consideration, it is evident that there are two urgent issues to consider: the development of methods to classify glaucoma in detail based on its pathology, and the improvement of clinical evaluation methods. In this review, we discuss some of our efforts to develop new neuroprotective agents for glaucoma, with a focus on the following three areas: 1. Clinical research and development of methods to classify glaucoma in detail based on IOP-independent factors, and the exploration of possibilities for the improvement of clinical evaluation of glaucoma. 2. Pathology-based research and development of new drugs for glaucoma, focusing on comprehensive gene expression analysis and the development of molecule-targeting drugs, using murine optic nerve crush as a disease model. 3. Development of next generation in vivo imaging modalities and the establishment of infrastructure enabling "big-data" analysis. First, we discuss our clinical research and the development of methods to classify glaucoma in detail based on IOP

  17. Blind estimation of shallow water acoustic channel

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    This paper proposed a method for blind estimation of underwater channels in shallow water environment by using received data at a single hydrophone or from single beam.First, the received signal is used for source signal reconstruction by means of signal-dependent TF (Time-Frequency) distribution, in association with instantaneous frequency estimation and TF inversion. Then the shallow-water channel estimation is achieved via WRELAX technique by use of the received signal and the estimated source signal. Finally, the results of numerical simulation and experimental test from real data taken in South China Sea trial have proved satisfactory. It is shown that the proposed method is useful for underwater channel estimation.

  18. Access to Mathematics by Blind Students: A Global Problem

    OpenAIRE

    Arthur I. Karshmer; Daryoush D. Farsi

    2007-01-01

    The issue of blindness and legally blind is becoming a global issue. Based on the last statistics from American Foundation for the blind, there are approximately 10 million blind and visually impaired people in the United States alone. Over 45 million people around the world are completely blind. 180 million more people are legally blind, and approximately 7 million people are diagnosed as blind or legally blind every year. One of the greatest stumbling blocks in the ability of the blind to e...

  19. New treatments of hereditary blindness

    DEFF Research Database (Denmark)

    Bertelsen, Mette; Rosenberg, Thomas; Larsen, Michael

    2013-01-01

    Ongoing clinical trials are targeting several previously intractable hereditary causes of blindness of congenital, childhood or early adulthood onset, mainly in the optic nerve and retina. The intended stage of initiation of the new therapeutic approaches ranges from neonatal life and a structura......Ongoing clinical trials are targeting several previously intractable hereditary causes of blindness of congenital, childhood or early adulthood onset, mainly in the optic nerve and retina. The intended stage of initiation of the new therapeutic approaches ranges from neonatal life and a...... structurally intact retinal tissue to adult life with a complete loss of photoreceptors. It must be assumed that some of the trials will succeed in producing new therapies and action must be taken to refine and accelerate diagnostics and to preserve therapeutic potential in blind people....

  20. Blind spectral unmixing based on sparse component analysis for hyperspectral remote sensing imagery

    Science.gov (United States)

    Zhong, Yanfei; Wang, Xinyu; Zhao, Lin; Feng, Ruyi; Zhang, Liangpei; Xu, Yanyan

    2016-09-01

    Recently, many blind source separation (BSS)-based techniques have been applied to hyperspectral unmixing. In this paper, a new blind spectral unmixing method based on sparse component analysis (BSUSCA) is proposed to solve the problem of highly mixed data. The BSUSCA algorithm consists of an alternative scheme based on two-block alternating optimization, by which we can simultaneously obtain the endmember signatures and their corresponding fractional abundances. According to the spatial distribution of the endmembers, the sparse properties of the fractional abundances are considered in the proposed algorithm. A sparse component analysis (SCA)-based mixing matrix estimation method is applied to update the endmember signatures, and the abundance estimation problem is solved by the alternating direction method of multipliers (ADMM). SCA is utilized for the unmixing due to its various advantages, including the unique solution and robust modeling assumption. The robustness of the proposed algorithm is verified through simulated experimental study. The experimental results using both simulated data and real hyperspectral remote sensing images confirm the high efficiency and precision of the proposed algorithm.

  1. PROXY BLIND SIGNATURE BASED ON ECDLP

    Directory of Open Access Journals (Sweden)

    SATARUPA PRADHAN,

    2011-03-01

    Full Text Available Proxy blind signature combines the properties of both proxy signature and blind signature. In a proxy signature scheme, a signer delegates his signing power to a proxy, who signs a message on behalf of the original signer. In a blind signature scheme, the signer cannot link the relationship between the blind message and the signature of the chosen message. Therefore, it is very suitable for electronic commerceapplication. In this paper, a proxy blind signature scheme based on ECDLP (Elliptic Curve Discrete Logarithm Problem has been proposed, which satisfy the security properties of both the blind signature and the proxy signature. Analysis shows that our scheme is secure and efficient.

  2. Night blindness and ancient remedy

    Directory of Open Access Journals (Sweden)

    H.A. Hajar Al Binali

    2014-01-01

    Full Text Available The aim of this article is to briefly review the history of night blindness and its treatment from ancient times until the present. The old Egyptians, the Babylonians, the Greeks and the Arabs used animal liver for treatment and successfully cured the disease. The author had the opportunity to observe the application of the old remedy to a patient. Now we know what the ancients did not know, that night blindness is caused by Vitamin A deficiency and the animal liver is the store house for Vitamin A.

  3. The Role of Memory Processes in Repetition Blindness

    Science.gov (United States)

    Johnston, James C.; Hochhaus, Larry; Null, Cynthia H. (Technical Monitor)

    1995-01-01

    We investigated whether Repetition Blindness (RB) in processing RSVP strings depends critically on memory demands. When all items in the sequence had to be reported, strong RB was found. When only the 2 critical items (cued by color) had to be reported, no RB was found. Preliminary results show that imposing a separate memory load, while reporting only the critical items, also produces little RB. Implications for the processing locus of RB will be discussed.

  4. Mammalian microevolution in action: adaptive edaphic genomic divergence in blind subterranean mole-rats.

    OpenAIRE

    Polyakov, Andrei; Beharav, Alex; Avivi, Aaron; Nevo, Eviatar

    2004-01-01

    Genomic diversity of anonymous regions across the genome, most probably including coding and noncoding amplified fragment length polymorphisms (AFLPs), was examined in 20 individuals of the blind mole-rat, Spalax galili, one of four allospecies of the Spalax ehrenbergi superspecies of blind subterranean mole-rats in Israel. We compared 10 individuals from two nearby populations in Upper Galilee, separated by only a few dozen to hundreds of metres and living in two sharply contrasting ecologie...

  5. Separation of multiple evoked responses using differential amplitude and latency variability

    CERN Document Server

    Knuth, K H; Bressler, S L; Ding, M; Knuth, Kevin H.; Truccolo, Wilson A.; Bressler, Steven L.; Ding, Mingzhou

    2001-01-01

    In neuroelectrophysiology one records electric potentials or magnetic fields generated by ensembles of synchronously active neurons in response to externally presented stimuli. These evoked responses are often produced by multiple generators in the presence of ongoing background activity. While source localization techniques or current source density estimation are usually used to identify generators, application of blind source separation techniques to obtain independent components has become more popular. We approach this problem by applying the Bayesian methodology to a more physiologically-realistic source model. As it is generally accepted that single trials vary in amplitude and latency, we incorporate this variability into the model. Rather than making the unrealistic assumption that these cortical components are independent of one another, our algorithm utilizes the differential amplitude and latency variability of the evoked waveforms to identify the cortical components. The algorithm is applied to i...

  6. A multi-scale morphological characterization of extended TeV survey sources

    Science.gov (United States)

    Schwarzburg, S.; Pühlhofer, G.; Santangelo, A.

    2012-12-01

    A recurrent topic in very high energy γ-ray astronomy is the morphological characterization of extended sources, which are lacking a clear counterpart in other wavelengths. Whithout a counterpart, the shape of such a source is not known a priori. Therefore blind/unbiased approaches are required to describe such a newly detected source in terms of detached emission regions (``features'') or eventually even separate objects. Ideally, the search takes into account the observation statistic and the instrument response (e.g. the exposure and the point spread function). And finally, a detection significance for the features needs to be provided.

  7. Blinding in randomized clinical trials: imposed impartiality

    DEFF Research Database (Denmark)

    Hróbjartsson, A; Boutron, I

    2011-01-01

    Blinding, or "masking," is a crucial method for reducing bias in randomized clinical trials. In this paper, we review important methodological aspects of blinding, emphasizing terminology, reporting, bias mechanisms, empirical evidence, and the risk of unblinding. Theoretical considerations...

  8. The Concept and Operations of Blind Number

    Institute of Scientific and Technical Information of China (English)

    PANG Yan-jun; LIU Kai-di; ZHANG Bo-wen

    2001-01-01

    This paper gives the definition and operations of blind number, and discusses its operationproperties. Blind number is a mathematical tool to express and deal with complex information with severalkinds of uncertainty.

  9. Elliptic Curve Blind Digital Signature Schemes

    Institute of Scientific and Technical Information of China (English)

    YOULin; YANGYixian; WENQiaoyan

    2003-01-01

    Blind signature schemes are important cryptographic protocols in guaranteeing the privacy or anonymity of the users.Three new blind signature schemes and their corresponding generalizations are pro-posed. Moreover, their securities are simply analyzed.

  10. Blindness Biggest Fear for Many Americans

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_160254.html Blindness Biggest Fear for Many Americans Losing vision would ... 4, 2016 THURSDAY, Aug. 4, 2016 (HealthDay News) -- Blindness is what many Americans fear most, a new ...

  11. Blinding in randomized clinical trials: imposed impartiality

    DEFF Research Database (Denmark)

    Hróbjartsson, A; Boutron, I

    2011-01-01

    Blinding, or "masking," is a crucial method for reducing bias in randomized clinical trials. In this paper, we review important methodological aspects of blinding, emphasizing terminology, reporting, bias mechanisms, empirical evidence, and the risk of unblinding. Theoretical considerations and...

  12. Overview on Deaf-Blindness

    Science.gov (United States)

    ... reading lip-reading speech Along with nonverbal and verbal conversations, a child who is deaf-blind needs a reliable routine of meaningful activities, and some way or ways that this routine can be communicated to her or him. Touch cues, gestures, and use of object symbols are some ...

  13. Vesicouterine fistula and blind vagina

    International Nuclear Information System (INIS)

    A case of vesicouterine fistula with blind vagina following cesarean section for obstructed labor is presented. It was surgically treated by fistulectomy, cervicoplasty and maintenance of bladder and cervical potency by catheterization. Intrauterine synechiae formation was prevented by copper T insertion and oral contraceptive pills. The patient is making uneventful a symptomatic progress planning to conceive. (author)

  14. Tactile maze solving in congenitally blind individuals

    DEFF Research Database (Denmark)

    Gagnon, Léa; Kupers, Ron; Schneider, Fabien C;

    2010-01-01

    Vision is undoubtedly important for navigation although not essential as blind individuals outperform their blindfolded seeing counterparts in a variety of navigational tasks. It is believed that the blind's superior performance is because of their efficient use of proprioceptive signals and envi......Vision is undoubtedly important for navigation although not essential as blind individuals outperform their blindfolded seeing counterparts in a variety of navigational tasks. It is believed that the blind's superior performance is because of their efficient use of proprioceptive signals...

  15. Blind Image Seperation Using Forward Difference Method (FDM

    Directory of Open Access Journals (Sweden)

    Jyothirmayi M

    2011-12-01

    Full Text Available In this paper, blind image separation is performed, exploiting the property of sparseness to representimages. A new sparse representation called forward difference method is proposed. It is known that most ofthe independent component analysis (ICA basis functions, extracted from images are sparse and givesunreliable sparseness measure. In the proposed method, the image mixture is first transformed to sparseimages. These images are divided into blocks and for each block the sparseness measure 0 norm isapplied. The block having the most sparseness is considered to determine the separation matrix. Theefficiency of the proposed method is compared with other sparse representation functions.

  16. Resources for Visually Impaired or Blind Students.

    Science.gov (United States)

    Hart, Elizabeth

    2000-01-01

    Suggests resources for school librarians who need materials for visually impaired or blind students. Highlights include the National Library Service for the Blind and Physically Handicapped; Louis Database of Accessible Materials for People Who Are Blind or Visually Impaired; Braille books; large print books, audio books; assistive technology; and…

  17. Occupant satisfaction with two blind control strategies

    DEFF Research Database (Denmark)

    Karlsen, Line Røseth; Heiselberg, Per Kvols; Bryn, Ida

    2015-01-01

    Highlights •Occupant satisfaction with two blind control strategies has been studied. •Control based on cut-off position of slats was more popular than closed slats. •Results from the study are helpful in development of control strategies for blinds. •The results give indications of how blinds...

  18. 45 CFR 233.70 - Blindness.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 2 2010-10-01 2010-10-01 false Blindness. 233.70 Section 233.70 Public Welfare... FINANCIAL ASSISTANCE PROGRAMS § 233.70 Blindness. (a) State plan requirements. A State plan under title X or XVI of the Social Security Act must: (1) Contain a definition of blindness in terms of...

  19. Change detection and change blindness in pigeons (Columba livia).

    Science.gov (United States)

    Herbranson, Walter T; Trinh, Yvan T; Xi, Patricia M; Arand, Mark P; Barker, Michael S K; Pratt, Theodore H

    2014-05-01

    Change blindness is a phenomenon in which even obvious details in a visual scene change without being noticed. Although change blindness has been studied extensively in humans, we do not yet know if it is a phenomenon that also occurs in other animals. Thus, investigation of change blindness in a nonhuman species may prove to be valuable by beginning to provide some insight into its ultimate causes. Pigeons learned a change detection task in which pecks to the location of a change in a sequence of stimulus displays were reinforced. They were worse at detecting changes if the stimulus displays were separated by a brief interstimulus interval, during which the display was blank, and this primary result matches the general pattern seen in previous studies of change blindness in humans. A second experiment attempted to identify specific stimulus characteristics that most reliably produced a failure to detect changes. Change detection was more difficult when interstimulus intervals were longer and when the change was iterated fewer times.

  20. From" Televised Blind Date” to" Televised Half-blind Wedding”

    Institute of Scientific and Technical Information of China (English)

    倪俊

    2001-01-01

    @@ A couple of weeks ago I happened to see on TV how American young men and women go out on "blind dates” , arranged by a television station. It is interesting to see how a young man and a young woman enjoy playing, dining or chatting with each other happily and naturally before a TV camera, even though they have never known or met with each other before. Yesterday evening one of the biggest national TV stations, FOX by name, made another bold try by broadcasting live a "half-blind wedding” to the whole country. It is such an original and also absurd idea that 1 think only American television-men can have figured it out and carried it out.

  1. From "Televised Blind Date" to "Televised Half-blind Wedding"

    Institute of Scientific and Technical Information of China (English)

    倪俊

    2001-01-01

    A couple of weeks ago I happened to see on TV how American young men and women go out on "blind dates", arranged by a television station, It is interesting to see bow a young man and a young woman enjoy playing, dining or chatting with each other happily and naturally before a TV camera, even though they have never known or met with each other before. Yesterday evening one of the biggest national TV stations, FOX by name, made another bold try by broadcasting live a "half-blind wedding" to the whole country. It is such an original and also absurd idea that I think only American television-men can have figured it out and carried it out. In the beginning, the directors of FOX put ads in newspapers, openly asking the public: "Who wants to marry a multi-millionaire?" It did not cost much time or

  2. CENTRIFUGAL SEPARATORS

    Science.gov (United States)

    Skarstrom, C.

    1959-03-10

    A centrifugal separator is described for separating gaseous mixtures where the temperature gradients both longitudinally and radially of the centrifuge may be controlled effectively to produce a maximum separation of the process gases flowing through. Tbe invention provides for the balancing of increases and decreases in temperature in various zones of the centrifuge chamber as the result of compression and expansions respectively, of process gases and may be employed effectively both to neutralize harmful temperature gradients and to utilize beneficial temperaturc gradients within the centrifuge.

  3. Blindness and severe visual impairment in pupils at schools for the blind in Burundi

    OpenAIRE

    Patrick Ruhagaze; Kahaki Kimani Margaret Njuguna; Lévi Kandeke; Paul Courtright

    2013-01-01

    Purpose: To determine the causes of childhood blindness and severe visual impairment in pupils attending schools for the blind in Burundi in order to assist planning for services in the country. Materials and Methods: All pupils attending three schools for the blind in Burundi were examined. A modified WHO/PBL eye examination record form for children with blindness and low vision was used to record the findings. Data was analyzed for those who became blind or severely visually impaired be...

  4. Rapid Assessment of Avoidable Blindness in Western Rwanda: Blindness in a Postconflict Setting

    OpenAIRE

    Wanjiku Mathenge; John Nkurikiye; Hans Limburg; Hannah Kuper

    2007-01-01

    Editors' Summary Background. VISION 2020, a global initiative that aims to eliminate avoidable blindness, has estimated that 75% of blindness worldwide is treatable or preventable. The WHO estimates that in Africa, around 9% of adults aged over 50 are blind. Some data suggest that people living in regions affected by violent conflict are more likely to be blind than those living in unaffected regions. Currently no data exist on the likely prevalence of blindness in Rwanda, a central African c...

  5. Blind identification of cellular phone cameras

    Science.gov (United States)

    Çeliktutan, Oya; Avcibas, Ismail; Sankur, Bülent

    2007-02-01

    In this paper, we focus on blind source cell-phone identification problem. It is known various artifacts in the image processing pipeline, such as pixel defects or unevenness of the responses in the CCD sensor, black current noise, proprietary interpolation algorithms involved in color filter array [CFA] leave telltale footprints. These artifacts, although often imperceptible, are statistically stable and can be considered as a signature of the camera type or even of the individual device. For this purpose, we explore a set of forensic features, such as binary similarity measures, image quality measures and higher order wavelet statistics in conjunction SVM classifier to identify the originating cell-phone type. We provide identification results among 9 different brand cell-phone cameras. In addition to our initial results, we applied a set of geometrical operations to original images in order to investigate how much our proposed method is robust under these manipulations.

  6. Glycoprotein degradation in the blind loop syndrome: identification of glycosidases in jejunal contents.

    Science.gov (United States)

    Prizont, R

    1981-02-01

    Contents obtained from jejunum of normal controls, self-emptying and self-filling blind loop rats were analyzed for the presence of glycoprotein-degrading glycosidases. The blind loop syndrome was documented by the increased fat excretion and slower growth rate of self-filling blind loop rats 6 wk after surgery. With p-nitrophenylglycosides as substrate, the specific activity of alpha-N-acetylgalactosaminidase, a potential blood group A destroying glycosidase, was 0.90+/-0.40 mU/mg of protein. This level was 23-fold higher than the specific activity of normal controls. In partially purified self-filling blind loop contents, the activity of alpha-N-acetylgalactosaminidase was 9- to 70-fold higher than activities of self-emptying and normal controls. Antibiotic treatment with chloromycetin and polymyxin decreased 24-fold the glycosidase levels in self-filling blind loops. In experiments with natural substrate, the blood group A titer of a20,000g supernate from normal jejunal homogenates decreased 128-fold after 24-h incubation with blind loop contents. Normal contents failed to diminish the blood group reactivity of the natural substrate. Furthermore, blind loop contents markedly decreased the blood group A titer of isolated brush borders. Incubation between blind loop bacteria and mucosal homogenates or isolated brush borders labeled with d-[U-(14)C]glucosamine revealed increased production of labeled ether extractable organic acids. Likewise, intraperitoneal injection of d-[U-(14)C]glucosamine into self-filling blind loop rats resulted in incorporation of the label into luminal short chain fatty acids. These results suggest that glycosidases may provide a mechanism by which blind loop bacteria obtain sugars from intestinal glycoproteins. The released sugars are used and converted by bacteria into energy and organic acids. This use of the host's glycoproteins would allow blind loop bacteria to grow and survive within the lumen independent of exogenous sources.

  7. Separations chemistry

    International Nuclear Information System (INIS)

    Results of studies on the photochemistry of aqueous Pu solutions and the stability of iodine in liquid and gaseous CO2 are reported. Progress is reported in studies on: the preparation of macroporous bodies filled with oxides and sulfides to be used as adsorbents; the beneficiation of photographic wastes; the anion exchange adsorption of transition elements from thiosulfate solutions; advanced filtration applications of energy significance; high-resolution separations; and, the examination of the separation agents, octylphenylphosphoric acid (OPPA) and trihexyl phosphate (THP)

  8. Product separator

    Science.gov (United States)

    Welsh, Robert A.; Deurbrouck, Albert W.

    1976-01-20

    A secondary light sensitive photoelectric product separator for use with a primary product separator that concentrates a material so that it is visually distinguishable from adjacent materials. The concentrate separation is accomplished first by feeding the material onto a vibratory inclined surface with a liquid flow, such as a wet concentrating table. Vibrations generally perpendicular to the stream direction of flow cause the concentrate to separate from its mixture according to its color. When the concentrate and its surrounding stream reach the recovery end of the table, a detecting device notes the line of color demarcation and triggers a signal if it differs from a normal condition. If no difference is noted nothing moves on the second separator. However, if a difference is detected in the constant monitoring of the color line's location, a product splitter and recovery unit normally positioned near the color line at the recovery end, moves to a new position. In this manner the selected separated concentrate is recovered at a maximum rate regardless of variations in the flow stream or other conditions present.

  9. Simplified heat transfer analysis for windows with venetian blinds: a comparative study

    Energy Technology Data Exchange (ETDEWEB)

    Lomanowski, B.A.; Wright, J.L. [Waterloo Univ., ON (Canada). Dept. of Mechanical Engineering

    2007-07-01

    A heat transfer analysis of a window with a light- and dark-coloured venetian blind in 3 different glazing and shading configurations was presented. The contributions of total solar transmission, longwave radiant gain and convective gain to net heat gain were investigated. The glazing/shading system consisted of 2 glazing layers and 1 venetian blind layer. The Yahoda and Wright method was used to calculate the effective longwave radiative properties of the blind. Absorbed quantities of solar radiation in each layer were calculated with a simplified solar optical model. A 1-D center-glass multi-layer heat transfer analysis was then performed. Various convection models were used to characterize each blind configuration. An empirical correlation for free convection on a vertical surface was used to obtain the average Nusselt number of the inside glazing layer. Convection on the outdoor glazing and blind was modelled using a forced convection correlation. Results from the simplified solar-optical model were then combined with the heat transfer analysis. Meteorological data were used to consider the configurations in both winter and summer conditions. Hourly results for the between the panes blind configuration showed a significant reduction in net heat gain. The outdoor blind configurations showed a dramatic reduction in net heat gain. Solar transmission was higher with the light-coloured blind. The optimum blind position in the terms of energy savings was the outdoor side blind. It was concluded that the ability to quantify the contribution of separate heat gain components offers significant insight into the thermal characteristics of complex glazing and shading systems. 17 refs., 1 tab., 10 figs.

  10. Demonstration of blind quantum computing.

    Science.gov (United States)

    Barz, Stefanie; Kashefi, Elham; Broadbent, Anne; Fitzsimons, Joseph F; Zeilinger, Anton; Walther, Philip

    2012-01-20

    Quantum computers, besides offering substantial computational speedups, are also expected to preserve the privacy of a computation. We present an experimental demonstration of blind quantum computing in which the input, computation, and output all remain unknown to the computer. We exploit the conceptual framework of measurement-based quantum computation that enables a client to delegate a computation to a quantum server. Various blind delegated computations, including one- and two-qubit gates and the Deutsch and Grover quantum algorithms, are demonstrated. The client only needs to be able to prepare and transmit individual photonic qubits. Our demonstration is crucial for unconditionally secure quantum cloud computing and might become a key ingredient for real-life applications, especially when considering the challenges of making powerful quantum computers widely available.

  11. Catalog Production for the DES Blind Cosmology Challenge

    Science.gov (United States)

    Busha, Michael T.; Wechsler, R. H.; Becker, M. R.; Erickson, B.; Evrard, A. E.

    2013-01-01

    The Blind Cosmology Challenge (BCC) is an effort by the Dark Energy Survey (DES) to test analysis tools for extracting cosmological information using a set of detailed synthetic galaxy catalogs. Here, we describe the creation of these synthetic sky catalogs based on requirements of the optical (DES) and the near-IR VISTA Hemisphere Survey, producing catalogs covering a quarter of the sky to z ˜ 2, with sources complete to r ˜ 25. Starting with a nested set of lightcone outputs of large, N-body simulation, galaxies are assigned to the dark matter distribution using an empirical algorithm that is tunable to match observed evolution of low-order galaxy population properties (counts and spatial clustering) in luminosity-color-density space. Galaxies are lensed by matter along the line of sight (including magnification, shape distortion, and multiple images), using a new algorithm that calculates shear with 3.22 arcsec resolution at galaxy positions in the full catalog. The catalog is well suited to support DES+VISTA joint studies of galaxy clustering, groups and clusters of galaxies, and gravitational lensing, and we highlight their application to the ongoing DES BBCC. Catalogs include ˜320 million galaxies and ˜150 million stars, with realistic colors, shapes and photometric errors. Using the expected DES photometric errors, three independent photometric redshift codes are run on the catalog, two of which produce full probability distributions. The synthetic observable catalog includes object position, magnitudes in the DES and VISTA bands, photometric errors, photometric redshifts, size, ellipticity, for each of ˜ 500 million objects. The galaxy distribution is additionally masked appropriately for the 5000 square degree DES footprint, including the impact of bright stars. In addition, we offer separate catalogs with magnitudes for additional existing and planned surveys, including SDSS, CFHTLS, HSC, LSST, and Euclid.

  12. Outage analysis of blind cooperative diversity

    KAUST Repository

    Tourki, Kamel

    2011-06-06

    Mobile users with single antennas can still take advantage of spatial diversity through cooperative space-time-encoded transmission. In this paper, we considered a scheme in which a relay chooses to cooperate only if its source-relay channel is of an acceptable quality, and we evaluate the usefulness of relaying when the source acts blindly and ignores the decision of the relays whether they may cooperate or not. In our study, we consider the regenerative relays in which the decisions to cooperate are based on a targeted end-to-end data rate R. We derived the end-to-end outage probability for a transmission rate R and a code rate ρ and look at a power allocation strategy between the source and the relays in order to minimize the end-to-end outage probability at the destination for high signal-to-noise ratio, by using the golden section search method. Performance results show that the computer simulations-based results coincide with our analytical results. Copyright © 2011 John Wiley & Sons, Ltd.

  13. Using isotopes of dissolved inorganic carbon species and water to separate sources of recharge in a cave spring, northwestern Arkansas, USA Blowing Spring Cave

    Science.gov (United States)

    Knierim, Katherine Joy; Pollock, Erik; Hays, Phillip D.

    2013-01-01

    Blowing Spring Cave in northwestern Arkansas is representative of cave systems in the karst of the Ozark Plateaus, and stable isotopes of water (δ18O and δ2H) and inorganic carbon (δ13C) were used to quantify soil-water, bedrock-matrix water, and precipitation contributions to cave-spring flow during storm events to understand controls on cave water quality. Water samples from recharge-zone soils and the cave were collected from March to May 2012 to implement a multicomponent hydrograph separation approach using δ18O and δ2H of water and dissolved inorganic carbon (δ13C–DIC). During baseflow, median δ2H and δ18O compositions were –41.6‰ and –6.2‰ for soil water and were –37.2‰ and –5.9‰ for cave water, respectively. Median DIC concentrations for soil and cave waters were 1.8 mg/L and 25.0 mg/L, respectively, and median δ13C–DIC compositions were –19.9‰ and –14.3‰, respectively. During a March storm event, 12.2 cm of precipitation fell over 82 h and discharge increased from 0.01 to 0.59 m3/s. The isotopic composition of precipitation varied throughout the storm event because of rainout, a change of 50‰ and 10‰ for δ2H and δ18O was observed, respectively. Although, at the spring, δ2H and δ18O only changed by approximately 3‰ and 1‰, respectively. The isotopic compositions of precipitation and pre-event (i.e., soil and bedrock matrix) water were isotopically similar and the two-component hydrograph separation was inaccurate, either overestimating (>100%) or underestimating (<0%) the precipitation contribution to the spring. During the storm event, spring DIC and δ13C–DIC decreased to a minimum of 8.6 mg/L and –16.2‰, respectively. If the contribution from precipitation was assumed to be zero, soil water was found to contribute between 23 to 72% of the total volume of discharge. Although the assumption of negligible contributions from precipitation is unrealistic, especially in karst systems where rapid flow

  14. Distribution characteristics of radon and its progeny in blind roadway with forced ventilation

    International Nuclear Information System (INIS)

    The blind roadway is not only the important workplaces, but also is important site of radon and its progeny generating and gathering, it is an important guiding significance for ventilation protection design to study distribution characteristics of radon and its progeny in blind roadway. Therefore, at first, the paper expounded the mathematical relationship between radon activity concentration with alpha potential concentration of radon progeny. Then, analyzed the sources of radon and its progeny, and established mathematical calculation model of Distribution characteristics of radon and its progeny in blind roadway with forced ventilation, respectively. Finally, using mathematical calculation models to analyze the influence law of multiple factors. (authors)

  15. Multi-frame partially saturated images blind deconvolution

    Science.gov (United States)

    Ye, Pengzhao; Feng, Huajun; Xu, Zhihai; Li, Qi; Chen, Yueting

    2016-09-01

    When blurred images have saturated or over-exposed pixels, conventional blind deconvolution approaches often fail to estimate accurate point spread function (PSF) and will introduce local ringing artifacts. In this paper, we propose a method to deal with the problem under the modified multi-frame blind deconvolution framework. First, in the kernel estimation step, a light streak detection scheme using multi-frame blurred images is incorporated into the regularization constraint. Second, we deal with image regions affected by the saturated pixels separately by modeling a weighted matrix during each multi-frame deconvolution iteration process. Both synthetic and real-world examples show that more accurate PSFs can be estimated and restored images have richer details and less negative effects compared to state of art methods.

  16. An alternating minimization method for blind deconvolution from Poisson data

    International Nuclear Information System (INIS)

    Blind deconvolution is a particularly challenging inverse problem since information on both the desired target and the acquisition system have to be inferred from the measured data. When the collected data are affected by Poisson noise, this problem is typically addressed by the minimization of the Kullback-Leibler divergence, in which the unknowns are sought in particular feasible sets depending on the a priori information provided by the specific application. If these sets are separated, then the resulting constrained minimization problem can be addressed with an inexact alternating strategy. In this paper we apply this optimization tool to the problem of reconstructing astronomical images from adaptive optics systems, and we show that the proposed approach succeeds in providing very good results in the blind deconvolution of nondense stellar clusters

  17. Independent EEG sources are dipolar.

    Directory of Open Access Journals (Sweden)

    Arnaud Delorme

    Full Text Available Independent component analysis (ICA and blind source separation (BSS methods are increasingly used to separate individual brain and non-brain source signals mixed by volume conduction in electroencephalographic (EEG and other electrophysiological recordings. We compared results of decomposing thirteen 71-channel human scalp EEG datasets by 22 ICA and BSS algorithms, assessing the pairwise mutual information (PMI in scalp channel pairs, the remaining PMI in component pairs, the overall mutual information reduction (MIR effected by each decomposition, and decomposition 'dipolarity' defined as the number of component scalp maps matching the projection of a single equivalent dipole with less than a given residual variance. The least well-performing algorithm was principal component analysis (PCA; best performing were AMICA and other likelihood/mutual information based ICA methods. Though these and other commonly-used decomposition methods returned many similar components, across 18 ICA/BSS algorithms mean dipolarity varied linearly with both MIR and with PMI remaining between the resulting component time courses, a result compatible with an interpretation of many maximally independent EEG components as being volume-conducted projections of partially-synchronous local cortical field activity within single compact cortical domains. To encourage further method comparisons, the data and software used to prepare the results have been made available (http://sccn.ucsd.edu/wiki/BSSComparison.

  18. Provably secure robust threshold partial blind signature

    Institute of Scientific and Technical Information of China (English)

    CAO Zhenfu; ZHU Haojin; LU Rongxing

    2006-01-01

    Threshold digital signature and blind signature are playing important roles in cryptography as well as in practical applications such as e-cash and e-voting systems.Over the past few years, many cryptographic researchers have made considerable headway in this field. However, to our knowledge, most of existing threshold blind signature schemes are based on the discrete logarithm problem. In this paper, we propose a new robust threshold partial blind signature scheme based on improved RSA cryptosystem.This scheme is the first threshold partial blind signature scheme based on factoring, and the robustness of threshold partial blind signature is also introduced. Moreover, in practical application, the proposed scheme will be especially suitable for blind signature-based voting systems with multiple administrators and secure electronic cash systems to prevent their abuse.

  19. Blind Decoding of Multiple Description Codes over OFDM Systems via Sequential Monte Carlo

    Directory of Open Access Journals (Sweden)

    Guo Dong

    2005-01-01

    Full Text Available We consider the problem of transmitting a continuous source through an OFDM system. Multiple description scalar quantization (MDSQ is applied to the source signal, resulting in two correlated source descriptions. The two descriptions are then OFDM modulated and transmitted through two parallel frequency-selective fading channels. At the receiver, a blind turbo receiver is developed for joint OFDM demodulation and MDSQ decoding. Transformation of the extrinsic information of the two descriptions are exchanged between each other to improve system performance. A blind soft-input soft-output OFDM detector is developed, which is based on the techniques of importance sampling and resampling. Such a detector is capable of exchanging the so-called extrinsic information with the other component in the above turbo receiver, and successively improving the overall receiver performance. Finally, we also treat channel-coded systems, and a novel blind turbo receiver is developed for joint demodulation, channel decoding, and MDSQ source decoding.

  20. Sensory augmentation for the blind

    Directory of Open Access Journals (Sweden)

    Silke Manuela Kärcher

    2012-03-01

    Full Text Available Enacted theories of consciousness conjecture that perception and cognition arise from an active experience of the regular relations that are tying together the sensory stimulation of different modalities and associated motor actions. Previous experiments investigated this concept by employing the technique of sensory substitution. Building on these studies, here we test a set of hypotheses derived from this framework and investigate the utility of sensory augmentation in handicapped people. We provide a late blind subject with a new set of sensorimotor laws: A vibro-tactile belt continually signals the direction of magnetic north. The subject completed a set of behavioral tests before and after an extended training period. The tests were complemented by questionnaires and interviews. This newly supplied information improved performance on different time scales. In a pointing task we demonstrate an instant improvement of performance based on the signal provided by the device. Furthermore, the signal was helpful in relevant daily tasks, often complicated for the blind, such as keeping a direction over longer distances or taking shortcuts in familiar environments. A homing task with an additional attentional load demonstrated a significant improvement after training. The subject found the directional information highly expedient for the adjustment of his inner maps of familiar environments and describes an increase in his feeling of security when exploring unfamiliar environments with the belt. The results give evidence for a firm integration of the newly supplied signals into the behavior of this late blind subject with better navigational performance and more courageous behavior in unfamiliar environments. Most importantly, the complementary information provided by the belt lead to a positive emotional impact with enhanced feeling of security. This experimental approach demonstrates the potential of sensory augmentation devices for the help of

  1. Blindness. [prosthetic devices and sensory aids

    Science.gov (United States)

    Pudenz, R. H.

    1974-01-01

    The possibilities are considered that modern electronics and engineering have to offer the individual with a damaged or disordered nervous system, especially the blind person. Discussed are the incidence and principal causes of blindness, past research activities, and a capsule review of some of the more interesting programs designed to provide the blind with the ability to be mobile in their environment and to read printed matter.

  2. New Routes for the Production of Fission Products and Their Separation from the Source Material for the Development of Realistic Nuclear Forensic Debris

    Energy Technology Data Exchange (ETDEWEB)

    Gharibyan, N. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2015-10-14

    In order to fully characterize the NIF neutron spectrum, SAND-II-SNL software was requested/received from the Radiation Safety Information Computational Center. The software is designed to determine the neutron energy spectrum through analysis of experimental activation data. However, given that the source code was developed in Sparcstation 10, it is not compatible with current version of FORTRAN. Accounts have been established through the Lawrence Livermore National Laboratory’s High Performance Computing in order to access different compiles for FORTRAN (e.g. pgf77, pgf90). Additionally, several of the subroutines included in the SAND-II-SNL package have required debugging efforts to allow for proper compiling of the code.

  3. Physical interpretation and separation of eddy current pulsed thermography

    Science.gov (United States)

    Yin, Aijun; Gao, Bin; Yun Tian, Gui; Woo, W. L.; Li, Kongjing

    2013-02-01

    Eddy current pulsed thermography (ECPT) applies induction heating and a thermal camera for non-destructive testing and evaluation (NDT&E). Because of the variation in resultant surface heat distribution, the physical mechanism that corresponds to the general behavior of ECPT can be divided into an accumulation of Joule heating via eddy current and heat diffusion. However, throughout the literature, the heating mechanisms of ECPT are not given in detail in the above two thermal phenomena and they are difficult to be separated. Nevertheless, once these two physical parameters are separated, they can be directly used to detect anomalies and predict the variation in material properties such as electrical conductivity, magnetic permeability and microstructure. This paper reports physical interpretation of these two physical phenomena that can be found in different time responses given the ECPT image sequences. Based on the phenomenon and their behaviors, the paper proposes a statistical method based on single channel blind source separation to decompose the two physical phenomena using different stages of eddy current and thermal propagation from the ECPT images. Links between mathematical models and physical models have been discussed and verified. This fundamental understanding of transient eddy current distribution and heating propagation can be applied to the development of feature extraction and pattern recognition for the quantitative analysis of ECPT measurement images and defect characterization.

  4. CERTIFICATELESS SIGNATURE AND BLIND SIGNATURE

    Institute of Scientific and Technical Information of China (English)

    Zhang Lei; Zhang Futai

    2008-01-01

    Certificateless public key cryptography is a new paradigm introduced by AI-Riyami and Paterson. It eliminates the need of the certificates in traditional public key cryptosystems and the key escrow problem in IDentity-based Public Key Cryptography (ID-PKC). Due to the advantages of the certificateless public key cryptography,a new efficient certificateless pairing-based signature scheme is presented,which has some advantages over previous constructions in computational cost. Based on this new signature scheme,a certificateless blind signature scheme is proposed. The security of our schemes is proven based on the hardness of computational Diffie-Hellman problem.

  5. Application of Behavior Modification to Blind Children.

    Science.gov (United States)

    Hayes, Charles S.; Weinhouse, Ellen

    1978-01-01

    Research and application of principles of behavior modification with visually impaired and blind children are reviewed with particular attention to lower functioning multiply impaired children. (Author)

  6. Enhanced heat discrimination in congenital blindness

    DEFF Research Database (Denmark)

    Slimani, Hocine; Ptito, Maurice; Kupers, Ron

    2015-01-01

    of the stimulated skin surface or magnitude of the temperature shift. Increasing the size of the stimulated skin area increased the response criterion in the blind (p=0.022) but not in the sighted. Together, these findings show that congenitally blind individuals have enhanced temperature discrimination accuracy...... trials (ΔT = 0°C) were also included to test for false positive responses. We used signal detection theory model to analyze the data. Our data revealed that blind participants have a higher accuracy than the sighted (d': Blind=2.4 ± 1.0, Sighted=1.8 ± 0.7, p=0.025), regardless of the size...

  7. Blindness and Insight in King Lear

    Institute of Scientific and Technical Information of China (English)

    岳元玉

    2008-01-01

    This paper intends to explore how William Shakespeare illustrates the theme of blindness and insight in his great tragedy "King Lear".Four characters’ deeds and their fate are used as a case study to examine what blindness is,what insight is,and the relationship between the two.The writer finds that by depicting the characters’ deeds and their fate in a double plot,Shakespeare renders the folly of blindness,the transition from blindness to insight,and the use of reason and thought to understand the truth.

  8. GPS Separator

    CERN Multimedia

    2016-01-01

    Footage of the 70 degree ISOLDE GPS separator magnet MAG70 as well as the switchyard for the Central Mass and GLM (GPS Low Mass) and GHM (GPS High Mass) beamlines in the GPS separator zone. In the GPS20 vacuum sector equipment such as the long GPS scanner 482 / 483 unit, faraday cup FC 490, vacuum valves and wiregrid piston WG210 and WG475 and radiation monitors can also be seen. Also the RILIS laser guidance and trajectory can be seen, the GPS main beamgate switch box and the actual GLM, GHM and Central Beamline beamgates in the beamlines as well as the first electrostatic quadrupoles for the GPS lines. Close up of the GHM deflector plates motor and connections and the inspection glass at the GHM side of the switchyard.

  9. HRS Separator

    CERN Multimedia

    2016-01-01

    Footage of the 90 and 60 degree ISOLDE HRS separator magnets in the HRS separator zone. In the two vacuum sectors HRS20 and HRS30 equipment such as the HRS slits SL240, the HRS faraday cup FC300 and wiregrid WG210 can be spotted. Vacuum valves, turbo pumps, beamlines, quadrupoles, water and compressed air connections, DC and signal cabling can be seen throughout the video. The HRS main and user beamgate in the beamline between MAG90 and MAG60 and its switchboxes as well as all vacuum bellows and flanges are shown. Instrumentation such as the HRS scanner unit 482 / 483, the HRS WG470 wiregrid and slits piston can be seen. The different quadrupoles and supports are shown as well as the RILIS guidance tubes and installation at the magnets and the different radiation monitors.

  10. Component Separations

    OpenAIRE

    Heller, Lior; McNichols, Colton H.; Ramirez, Oscar M.

    2012-01-01

    Component separation is a technique used to provide adequate coverage for midline abdominal wall defects such as a large ventral hernia. This surgical technique is based on subcutaneous lateral dissection, fasciotomy lateral to the rectus abdominis muscle, and dissection on the plane between external and internal oblique muscles with medial advancement of the block that includes the rectus muscle and its fascia. This release allows for medial advancement of the fascia and closure of up to 20-...

  11. Component separations.

    Science.gov (United States)

    Heller, Lior; McNichols, Colton H; Ramirez, Oscar M

    2012-02-01

    Component separation is a technique used to provide adequate coverage for midline abdominal wall defects such as a large ventral hernia. This surgical technique is based on subcutaneous lateral dissection, fasciotomy lateral to the rectus abdominis muscle, and dissection on the plane between external and internal oblique muscles with medial advancement of the block that includes the rectus muscle and its fascia. This release allows for medial advancement of the fascia and closure of up to 20-cm wide defects in the midline area. Since its original description, components separation technique underwent multiple modifications with the ultimate goal to decrease the morbidity associated with the traditional procedure. The extensive subcutaneous lateral dissection had been associated with ischemia of the midline skin edges, wound dehiscence, infection, and seroma. Although the current trend is to proceed with minimally invasive component separation and to reinforce the fascia with mesh, the basic principles of the techniques as described by Ramirez et al in 1990 have not changed over the years. Surgeons who deal with the management of abdominal wall defects are highly encouraged to include this technique in their collection of treatment options. PMID:23372455

  12. WASTE PRINTED CIRCUIT BOARDS SEPARATION IN ELECTROSTATIC SEPARATOR

    OpenAIRE

    Branimir Fuk

    2012-01-01

    Printed circuit boards from electronic waste are very important source of precious metals by recycling. The biggest challenge is liberation and separation of useful components; thin film which contains copper, zinc, tin, lead and precious metals like silver, gold and palladium from non useful components; polymers, ceramics and glass fibbers. The paper presents results for separation of shredded printed circuit boards from TV sets in electrostatic separator. Testing where conducted with materi...

  13. Temporal dynamics of the Venetian blind effect.

    Science.gov (United States)

    Dobias, Joshua Jay; Stine, Wm Wren

    2012-05-01

    When square wave gratings are viewed binocularly with lower luminance or contrast in one eye, the individual bars of the grating appear to rotate around a vertical axis (Venetian blind effect). The effect has typically been thought to occur due to retinal disparities that result from irradiation and, therefore, are entirely entoptic. If so, the visual system should process disparities from a luminance or contrast disparity and a geometric disparity at the same rate. Studies of motion-in-depth using geometric disparities have shown that the visual system is unable to process depth cues when those cues are oscillated at frequencies greater than 5 Hz. By changing contrast (experiments one and two) and geometric (experiment three) disparity cues over time, the present study measured the frequency at which both the perception of motion-in-depth and the perception of depth diminish. The perception of motion-in-depth from contrast disparities decreased near 1.1 Hz (experiments one and four) and the perception of depth from contrast disparities decreased near 1.3 Hz (experiments one, two and four); both of which are lower than the frequency where depth from a geometric disparity diminished (near 4.8 Hz in experiment three). The differences between the dynamics of depth from contrast and geometric disparities suggest that the perception arises from separate neural mechanisms. PMID:22406308

  14. 42 CFR 436.531 - Determination of blindness.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Determination of blindness. 436.531 Section 436.531... Requirements for Medicaid Eligibility Blindness § 436.531 Determination of blindness. In determining blindness... determine on behalf of the agency— (1) Whether the individual meets the definition of blindness; and...

  15. ESTIMATION OF THE NUMBER OF CORRELATED SOURCES WITH COMMON FREQUENCIES BASED ON POWER SPECTRAL DENSITY

    Institute of Scientific and Technical Information of China (English)

    LI Ning; SHI Tielin

    2007-01-01

    Blind source Separation and estimation of the number of sources usually demand that the number of sensors should be greater than or equal to that of the sources, which, however, is very difficult to satisfy for the complex Systems. A new estimating method based on power spectral density (PSD) is presented. When the relation between the number of sensors and that of sources is unknown, the PSD matrix is first obtained by the ratio of PSD of the observation signals, and then the bound of the number of correlated sources with common frequencies can be estimated by comparing every column vector of PSD matrix. The effectiveness of the proposed method is verified by theoretical analysis and experiments, and the influence of noise on the estimation of number of source is simulated.

  16. A blind algorithm for recovering articulator positions from acoustics

    Energy Technology Data Exchange (ETDEWEB)

    Hogden, John E [Los Alamos National Laboratory

    2009-01-01

    MIMICRI is a signal-processing algorithm that has been shown to blindly infer and invert memoryless nonlinear functions of unobservable bandlimited signals, such as the mapping from the unobservable positions of the speech articulators to observable speech sounds. We review results of using MIMICRI on toy problems and on human speech data. We note that MIMICRI requires that the user specify two parameters: the dimensionality and pass-band of the unobservable signals. We show how to use cross-validation to help estimate the passband. An unexpected consequence of this work is that it helps separate signals with overlapping frequency bands.

  17. A semiotic approach to blind wayfinding: some primary conceptual standpoints

    Directory of Open Access Journals (Sweden)

    Marcelo Santos

    2009-01-01

    Full Text Available Researchers from a wide variety of disciplines, such as philosophy, art, education or psychology, have over the years sustained the idea that blind persons are incapable or nearly incapable of formulating complex mental diagrammatic representations, which are schema based on the similarities found within internal logical relations between sign and object.Contrary to this widely accepted opinion, we will present an alternative approach in this paper: Our main idea is that blind and visually impaired people relying upon tact as a main knowledge source are capable of diagrammatic reasoning very well, but use a different method for this purpose, namely the method of inductive reasoning. Such method can effectively provide the mind with the data necessary to the elaboration of mental maps. Therefore, wayfinding as a semiotic process in which a route is planned and executed from marks or navigation indexes, is also enabled by tact.

  18. S-K Smartphone Barcode Reader for the Blind

    Science.gov (United States)

    Tekin, Ender; Vásquez, David; Coughlan, James M.

    2014-01-01

    We describe a new smartphone app called BLaDE (Barcode Localization and Decoding Engine), designed to enable a blind or visually impaired user find and read product barcodes. Developed at The Smith-Kettlewell Eye Research Institute, the BLaDE Android app has been released as open source software, which can be used for free or modified for commercial or non-commercial use. Unlike popular commercial smartphone apps, BLaDE provides real-time audio feedback to help visually impaired users locate a barcode, which is a prerequisite to being able to read it. We describe experiments performed with five blind/visually impaired volunteer participants demonstrating that BLaDE is usable and that the audio feedback is key to its usability. PMID:25602592

  19. 75 FR 47304 - Accessible Mobile Phone Options for People Who Are Blind, Deaf-Blind, or Have Low Vision

    Science.gov (United States)

    2010-08-05

    ... COMMISSION Accessible Mobile Phone Options for People Who Are Blind, Deaf- Blind, or Have Low Vision AGENCY... accessible for people who are blind, have vision loss, or are deaf-blind and the extent to which gaps in...--that are accessible to people who are blind or have vision loss; technical obstacles, if any, to...

  20. Fast Monaural Separation of Speech

    DEFF Research Database (Denmark)

    Pontoppidan, Niels Henrik; Dyrholm, Mads

    2003-01-01

    a Factorial Hidden Markov Model, with non-stationary assumptions on the source autocorrelations modelled through the Factorial Hidden Markov Model, leads to separation in the monaural case. By extending Hansens work we find that Roweis' assumptions are necessary for monaural speech separation. Furthermore we...