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Sample records for based blind bernoulli-gaussian

  1. Partially Blind Signatures Based on Quantum Cryptography

    Science.gov (United States)

    Cai, Xiao-Qiu; Niu, Hui-Fang

    2012-12-01

    In a partially blind signature scheme, the signer explicitly includes pre-agreed common information in the blind signature, which can improve the availability and performance. We present a new partially blind signature scheme based on fundamental properties of quantum mechanics. In addition, we analyze the security of this scheme, and show it is not possible to forge valid partially blind signatures. Moreover, the comparisons between this scheme and those based on public-key cryptography are also discussed.

  2. 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.

  3. 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.

  4. An ECC-Based Blind Signature Scheme

    Directory of Open Access Journals (Sweden)

    Fuh-Gwo Jeng

    2010-08-01

    Full Text Available Cryptography is increasingly applied to the E-commerce world, especially to the untraceable payment system and the electronic voting system. Protocols for these systems strongly require the anonymous digital signature property, and thus a blind signature strategy is the answer to it. Chaum stated that every blind signature protocol should hold two fundamental properties, blindness and intractableness. All blind signature schemes proposed previously almost are based on the integer factorization problems, discrete logarithm problems, or the quadratic residues, which are shown by Lee et al. that none of the schemes is able to meet the two fundamental properties above. Therefore, an ECC-based blind signature scheme that possesses both the above properties is proposed in this paper.

  5. A New ID-Based Proxy Blind Signature Scheme

    Institute of Scientific and Technical Information of China (English)

    LANG Wei-min; YANG Zong-kai; CHENG Wen-qing; TAN Yun-meng

    2005-01-01

    An identity-based proxy blind signature scheme from bilinear pairings is introduced, which combines the advantages of proxy signature and blind signature. Furthermore, our scheme can prevent the original signer from generating the proxy blind signature, thus the profits of the proxy signer are guaranteed. We introduce bilinear pairings to minimize computational overhead and to improve the related performance of our scheme. In addition, the proxy blind signature presented is non-repudiable and it fulfills perfectly the security requirements of a proxy blind signature.

  6. GA based robust blind digital watermarking

    CERN Document Server

    Álvarez, Víctor; Frau, María-Dolores; Gudiel, Félix; Güemes, María-Belén; Martín, Elena; Osuna, Amparo

    2012-01-01

    A genetic algorithm based robust blind digital watermarking scheme is presented. Starting from a binary image (the original watermark), a genetic algorithm is performed searching for a permutation of this image which is as uncorrelated as possible to the original watermark. The output of the GA is used as our final watermark, so that both security and robustness in the watermarking process is improved. Now, the original cover image is partitioned into non-overlapped square blocks (depending on the size of the watermark image). Then a (possibly extended) Hadamard transform is applied to these blocks, so that one bit information from the watermark image is embedded in each block by modifying the relationship of two coefficients in the transformed matrices. The watermarked image is finally obtained by simply performing the inverse (extended) Hadamard transform on the modified matrices. The experimental results show that our scheme keeps invisibility, security and robustness more likely than other proposals in th...

  7. Blind Equalization Based on Evolution Strategies

    Institute of Scientific and Technical Information of China (English)

    SongYu; ZhangXianda; 等

    1997-01-01

    Conventional blind equalization algorithms suffer from ill convergence to local minima and slow convergence speed.This paper proposes a novel blind equalization algorithm.using random search methods-evolution strategies and existing cost functions,Simulation results verify the fast and global convergence of the proposed algorithm.

  8. A NEW EFFICIENT ID-BASED PROXY BLIND SIGNATURE SCHEME

    Institute of Scientific and Technical Information of China (English)

    Ming Yang; Wang Yumin

    2008-01-01

    In a proxy blind signature scheme, the proxy signer is allowed to generate a blind signature on behalf of the original signer. The proxy blind signature scheme is useful in several applications such as e-voting, e-payment, etc. Recently, Zheng, et al. presented an IDentity (ID)-based proxy blind signature. In this paper, a new efficient ID-based proxy blind signature scheme from bilinear pairings is proposed, which can satisfy the security properties of both the proxy signatures and the blind signature schemes. Analysis of the scheme efficiency shows that the new scheme is more efficient than Zheng, et al.'s scheme. The proposed scheme is more practical in the real world.

  9. Fuzzy-based simulation of real color blindness.

    Science.gov (United States)

    Lee, Jinmi; dos Santos, Wellington P

    2010-01-01

    About 8% of men are affected by color blindness. That population is at a disadvantage since they cannot perceive a substantial amount of the visual information. This work presents two computational tools developed to assist color blind people. The first one tests color blindness and assess its severity. The second tool is based on Fuzzy Logic, and implements a method proposed to simulate real red and green color blindness in order to generate synthetic cases of color vision disturbance in a statistically significant amount. Our purpose is to develop correction tools and obtain a deeper understanding of the accessibility problems faced by people with chromatic visual impairment.

  10. A weak blind signature scheme based on quantum cryptography

    Science.gov (United States)

    Wen, Xiaojun; Niu, Xiamu; Ji, Liping; Tian, Yuan

    2009-02-01

    In this paper, we present a weak blind signature scheme based on the correlation of EPR (Einstein-Padolsky-Rosen) pairs. Different from classical blind signature schemes and current quantum signature schemes, our quantum blind signature scheme could guarantee not only the unconditionally security but also the anonymity of the message owner. To achieve that, quantum key distribution and one-time pad are adopted in our scheme. Experimental analysis proved that our scheme have the characteristics of non-counterfeit, non-disavowal, blindness and traceability. It has a wide application to E-payment system, E-government, E-business, and etc.

  11. Blind Signature Scheme Based on Chebyshev Polynomials

    Directory of Open Access Journals (Sweden)

    Maheswara Rao Valluri

    2011-12-01

    Full Text Available A blind signature scheme is a cryptographic protocol to obtain a valid signature for a message from a signer such that signer’s view of the protocol can’t be linked to the resulting message signature pair. This paper presents blind signature scheme using Chebyshev polynomials. The security of the given scheme depends upon the intractability of the integer factorization problem and discrete logarithms ofChebyshev polynomials.

  12. Blind Signature Scheme Based on Chebyshev Polynomials

    OpenAIRE

    Maheswara Rao Valluri

    2011-01-01

    A blind signature scheme is a cryptographic protocol to obtain a valid signature for a message from a signer such that signer’s view of the protocol can’t be linked to the resulting message signature pair. This paper presents blind signature scheme using Chebyshev polynomials. The security of the given scheme depends upon the intractability of the integer factorization problem and discrete logarithms ofChebyshev polynomials.

  13. Blind guidance system based on laser triangulation

    Science.gov (United States)

    Wu, Jih-Huah; Wang, Jinner-Der; Fang, Wei; Lee, Yun-Parn; Shan, Yi-Chia; Kao, Hai-Ko; Ma, Shih-Hsin; Jiang, Joe-Air

    2012-05-01

    We propose a new guidance system for the blind. An optical triangulation method is used in the system. The main components of the proposed system comprise of a notebook computer, a camera, and two laser modules. The track image of the light beam on the ground or on the object is captured by the camera and then the image is sent to the notebook computer for further processing and analysis. Using a developed signal-processing algorithm, our system can determine the object width and the distance between the object and the blind person through the calculation of the light line positions on the image. A series of feasibility tests of the developed blind guidance system were conducted. The experimental results show that the distance between the test object and the blind can be measured with a standard deviation of less than 8.5% within the range of 40 and 130 cm, while the test object width can be measured with a standard deviation of less than 4.5% within the range of 40 and 130 cm. The application potential of the designed system to the blind guidance can be expected.

  14. A Proxy Blind Signature Scheme Based on ECDLP

    Institute of Scientific and Technical Information of China (English)

    WANGHaiyan; WANGRuchuan

    2005-01-01

    While proxy signature scheme enables an original signer to fully authorize a proxy to sign a message on his or her behalf legally and undeniably, blind signature scheme keeps the message blind from the signer so that the signer cannot make a linkage between the signature and the identity of requester (receiver). Both schemes have been widely applied in the electronic business. A new ECDLP (Elliptic curve discrete problem)-based proxy blind signature scheme is to be proposed in this paper by integrating the security properties of both schemes.

  15. Wavelet Based Semi-blind Channel Estimation For Multiband OFDM

    CERN Document Server

    Sadough, Sajad; Jaffrot, Emmanuel; Duhamel, Pierre

    2007-01-01

    This paper introduces an expectation-maximization (EM) algorithm within a wavelet domain Bayesian framework for semi-blind channel estimation of multiband OFDM based UWB communications. A prior distribution is chosen for the wavelet coefficients of the unknown channel impulse response in order to model a sparseness property of the wavelet representation. This prior yields, in maximum a posteriori estimation, a thresholding rule within the EM algorithm. We particularly focus on reducing the number of estimated parameters by iteratively discarding ``unsignificant'' wavelet coefficients from the estimation process. Simulation results using UWB channels issued from both models and measurements show that under sparsity conditions, the proposed algorithm outperforms pilot based channel estimation in terms of mean square error and bit error rate and enhances the estimation accuracy with less computational complexity than traditional semi-blind methods.

  16. Wavelet Based Semi-blind Channel Estimation For Multiband OFDM

    OpenAIRE

    Sadough, Sajad; Ichir, Mahieddine; Jaffrot, Emmanuel; Duhamel, Pierre

    2007-01-01

    This paper introduces an expectation-maximization (EM) algorithm within a wavelet domain Bayesian framework for semi-blind channel estimation of multiband OFDM based UWB communications. A prior distribution is chosen for the wavelet coefficients of the unknown channel impulse response in order to model a sparseness property of the wavelet representation. This prior yields, in maximum a posteriori estimation, a thresholding rule within the EM algorithm. We particularly focus on reducing the nu...

  17. A New Partially Blind Signature Based on Factoring and Discrete Logarithms

    Directory of Open Access Journals (Sweden)

    N. M.F. Tahat

    2008-01-01

    Full Text Available Partially blind signatures played an important role in many electronic commerce applications. Many existing partially blind signature scheme based on a single hard problem but not secure. In this study, we propose a secure partially blind signature scheme based on factoring and discrete logarithms and show that the proposed scheme satisfies the partial blindness, randomization, unlinkability and unforgeability properties. We also analyse the computation cost of the proposed scheme.

  18. Gauss-Newton based kurtosis blind deconvolution of spectroscopic data

    Institute of Scientific and Technical Information of China (English)

    Jinghe Yuan; Ziqiang Hu

    2006-01-01

    @@ The spectroscopic data recorded by dispersion spectrophotometer are usually degraded by the response function of the instrument. To improve the resolving power, double or triple cascade spectrophotometer and narrow slits have been employed, but the total flux of the radiation decreases accordingly, resulting in a lower signal-to-noise ratio (SNR) and a longer measuring time. However, the spectral resolution can be improved by mathematically removing the effect of the instrument response function. Based on the ShalviWeinstein criterion, a Gauss-Newton based kurtosis blind deconvolution algorithm for spectroscopic data is proposed. Experiments with some real measured Raman spectroscopic data show that this algorithm has excellent deconvolution capability.

  19. Fixed-point blind source separation algorithm based on ICA

    Institute of Scientific and Technical Information of China (English)

    Hongyan LI; Jianfen MA; Deng'ao LI; Huakui WANG

    2008-01-01

    This paper introduces the fixed-point learning algorithm based on independent component analysis (ICA);the model and process of this algorithm and simulation results are presented.Kurtosis was adopted as the estimation rule of independence.The results of the experiment show that compared with the traditional ICA algorithm based on random grads,this algorithm has advantages such as fast convergence and no necessity for any dynamic parameter,etc.The algorithm is a highly efficient and reliable method in blind signal separation.

  20. A Lattice-Based Identity-Based Proxy Blind Signature Scheme in the Standard Model

    Directory of Open Access Journals (Sweden)

    Lili Zhang

    2014-01-01

    Full Text Available A proxy blind signature scheme is a special form of blind signature which allowed a designated person called proxy signer to sign on behalf of original signers without knowing the content of the message. It combines the advantages of proxy signature and blind signature. Up to date, most proxy blind signature schemes rely on hard number theory problems, discrete logarithm, and bilinear pairings. Unfortunately, the above underlying number theory problems will be solvable in the postquantum era. Lattice-based cryptography is enjoying great interest these days, due to implementation simplicity and provable security reductions. Moreover, lattice-based cryptography is believed to be hard even for quantum computers. In this paper, we present a new identity-based proxy blind signature scheme from lattices without random oracles. The new scheme is proven to be strongly unforgeable under the standard hardness assumption of the short integer solution problem (SIS and the inhomogeneous small integer solution problem (ISIS. Furthermore, the secret key size and the signature length of our scheme are invariant and much shorter than those of the previous lattice-based proxy blind signature schemes. To the best of our knowledge, our construction is the first short lattice-based identity-based proxy blind signature scheme in the standard model.

  1. Navigation for the Blind through Audio-Based Virtual Environments.

    Science.gov (United States)

    Sánchez, Jaime; Sáenz, Mauricio; Pascual-Leone, Alvaro; Merabet, Lotfi

    2010-01-01

    We present the design, development and an initial study changes and adaptations related to navigation that take place in the brain, by incorporating an Audio-Based Environments Simulator (AbES) within a neuroimaging environment. This virtual environment enables a blind user to navigate through a virtual representation of a real space in order to train his/her orientation and mobility skills. Our initial results suggest that this kind of virtual environment could be highly efficient as a testing, training and rehabilitation platform for learning and navigation.

  2. 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.

  3. Blind test of physics-based prediction of protein structures.

    Science.gov (United States)

    Shell, M Scott; Ozkan, S Banu; Voelz, Vincent; Wu, Guohong Albert; Dill, Ken A

    2009-02-01

    We report here a multiprotein blind test of a computer method to predict native protein structures based solely on an all-atom physics-based force field. We use the AMBER 96 potential function with an implicit (GB/SA) model of solvation, combined with replica-exchange molecular-dynamics simulations. Coarse conformational sampling is performed using the zipping and assembly method (ZAM), an approach that is designed to mimic the putative physical routes of protein folding. ZAM was applied to the folding of six proteins, from 76 to 112 monomers in length, in CASP7, a community-wide blind test of protein structure prediction. Because these predictions have about the same level of accuracy as typical bioinformatics methods, and do not utilize information from databases of known native structures, this work opens up the possibility of predicting the structures of membrane proteins, synthetic peptides, or other foldable polymers, for which there is little prior knowledge of native structures. This approach may also be useful for predicting physical protein folding routes, non-native conformations, and other physical properties from amino acid sequences.

  4. Privacy Preserving Similarity Based Text Retrieval through Blind Storage

    Directory of Open Access Journals (Sweden)

    Pinki Kumari

    2016-09-01

    Full Text Available Cloud computing is improving rapidly due to their more advantage and more data owners give interest to outsource their data into cloud storage for centralize their data. As huge files stored in the cloud storage, there is need to implement the keyword based search process to data user. At the same time to protect the privacy of data, encryption techniques are used for sensitive data, that encryption is done before outsourcing data to cloud server. But it is critical to search results in encryption data. In this system we propose similarity text retrieval from the blind storage blocks with encryption format. This system provides more security because of blind storage system. In blind storage system data is stored randomly on cloud storage.  In Existing Data Owner cannot encrypt the document data as it was done only at server end. Everyone can access the data as there was no private key concept applied to maintained privacy of the data. But In our proposed system, Data Owner can encrypt the data himself using RSA algorithm.  RSA is a public key-cryptosystem and it is widely used for sensitive data storage over Internet. In our system we use Text mining process for identifying the index files of user documents. Before encryption we also use NLP (Nature Language Processing technique to identify the keyword synonyms of data owner document. Here text mining process examines text word by word and collect literal meaning beyond the words group that composes the sentence. Those words are examined in API of word net so that only equivalent words can be identified for index file use. Our proposed system provides more secure and authorized way of recover the text in cloud storage with access control. Finally, our experimental result shows that our system is better than existing.

  5. HOC Based Blind Identification of Hydroturbine Shaft Volterra System

    Directory of Open Access Journals (Sweden)

    Bing Bai

    2017-01-01

    Full Text Available In order to identify the quadratic Volterra system simplified from the hydroturbine shaft system, a blind identification method based on the third-order cumulants and a reversely recursive method are proposed. The input sequence of the system under consideration is an unobservable independent identically distributed (i.i.d., zero-mean and non-Gaussian stationary signal, and the observed signals are the superposition of the system output signal and Gaussian noise. To calculate the third-order moment of the output signal, a computer loop judgment method is put forward to determine the coefficient. When using optimization method to identify the time domain kernels, we combined the traditional optimization algorithm (direct search method with genetic algorithm (GA and constituted the hybrid genetic algorithm (HGA. Finally, according to the prototype observation signal and the time domain kernel parameters obtained from identification, the input signal of the system can be gained recursively. To test the proposed method, three numerical experiments and engineering application have been carried out. The results show that the method is applicable to the blind identification of the hydroturbine shaft system and has strong universality; the input signal obtained by the reversely recursive method can be approximately taken as the random excitation acted on the runner of the hydroturbine shaft system.

  6. Untraceable partially blind signature based on DLOG problem

    Institute of Scientific and Technical Information of China (English)

    黄征; 陈克非; 冠卫东

    2004-01-01

    This paper proposes a new untraceable Partially Blind Signature scheme which is a cross between the traditional signature scheme and the blind signature scheme. In this proposed scheme, the message M that the signer signed can be divided into two parts. The first part can be known to the signer (like that in the traditional signature scheme) while the other part cannot be known to the signer (like that in the blind signature scheme). After having signed M, the signer cannot determine if he has made the signature of M except through the part that he knows. We draw ideas from Brands' "Restricted Blind Signature" to solve the Untraceable Partially Blind Signature problem. Our scheme is a probabilistic signature scheme and the security of our Untraceable Partially Blind Signature scheme relies on the difficulty of computing discrete logarithm.

  7. A Smart Infrared Microcontroller-Based Blind Guidance System

    Directory of Open Access Journals (Sweden)

    Amjed S. Al-Fahoum

    2013-01-01

    Full Text Available Blindness is a state of lacking the visual perception due to physiological or neurological factors. The partial blindness represents the lack of integration in the growth of the optic nerve or visual centre of the eye, and total blindness is the full absence of the visual light perception. In this work, a simple, cheap, friendly user, smart blind guidance system is designed and implemented to improve the mobility of both blind and visually impaired people in a specific area. The proposed work includes a wearable equipment consists of head hat and mini hand stick to help the blind person to navigate alone safely and to avoid any obstacles that may be encountered, whether fixed or mobile, to prevent any possible accident. The main component of this system is the infrared sensor which is used to scan a predetermined area around blind by emitting-reflecting waves. The reflected signals received from the barrier objects are used as inputs to PIC microcontroller. The microcontroller is then used to determine the direction and distance of the objects around the blind. It also controls the peripheral components that alert the user about obstacle's shape, material, and direction. The implemented system is cheap, fast, and easy to use and an innovative affordable solution to blind and visually impaired people in third world countries.

  8. Envelope based nonlinear blind deconvolution approach for ultrasound imaging

    Directory of Open Access Journals (Sweden)

    L.T. Chira

    2012-06-01

    Full Text Available The resolution of ultrasound medical images is yet an important problem despite of the researchers efforts. In this paper we presents a nonlinear blind deconvolution to eliminate the blurring effect based on the measured radio-frequency signal envelope. This algorithm is executed in two steps. Firslty we make an estimation for Point Spread Function (PSF and, secondly we use the estimated PSF to remove, iteratively their effect. The proposed algorithm is a greedy algorithm, called also matching pursuit or CLEAN. The use of this algorithm is motivated beacause theorically it avoid the so called inverse problem, which usually needs regularization to obtain an optimal solution. The results are presented using 1D simulated signals in term of visual evaluation and nMSE in comparison with the two most kwown regularisation solution methods for least square problem, Thikonov regularization or l2-norm and Total Variation or l1 norm.

  9. A Quantum Proxy Weak Blind Signature Scheme Based on Controlled Quantum Teleportation

    Science.gov (United States)

    Cao, Hai-Jing; Yu, Yao-Feng; Song, Qin; Gao, Lan-Xiang

    2015-04-01

    Proxy blind signature is applied to the electronic paying system, electronic voting system, mobile agent system, security of internet, etc. A quantum proxy weak blind signature scheme is proposed in this paper. It is based on controlled quantum teleportation. Five-qubit entangled state functions as quantum channel. The scheme uses the physical characteristics of quantum mechanics to implement message blinding, so it could guarantee not only the unconditional security of the scheme but also the anonymity of the messages owner.

  10. 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.

  11. Euclidean Distance Distortion Based Robust and Blind Mesh Watermarking

    Directory of Open Access Journals (Sweden)

    Yesmine Ben Amar

    2016-12-01

    Full Text Available The three-dimensional (3D polygonal meshes are recently widely used in several domains, which necessitate the realistic visualization of the objects. Moreover, there is an urgent need to protect the 3D data properties for preventing unauthorized reproduction. The 3D digital watermarking technology is one of the best solutions to protect data from piracy during transmission through the internet. The current work proposed a novel robust watermarking scheme of polygonal meshes for copyright protection purposes. The proposed algorithm is based on the characteristics of the mesh geometry to embed a sequence of data bits into the object by slightly adjusting the vertex positions. Furthermore, the proposed method used a blind detection scheme. The watermarked model is perceptually indistinguishable from the original one and the embedded watermark is invariant to affine transformation. Through simulations, the quality of the watermarked object as well as the inserted watermark robustness against various types of attacks were tested and evaluated to prove the validity and the efficiency of our algorithm.

  12. Difference Energy Based Blind Image Watermarking Resisting to Geometrical Distortions

    Institute of Scientific and Technical Information of China (English)

    YU Yanwei; LU Zhengding; LING Hefei

    2006-01-01

    In this paper a blind image watermarking that can resist to rotation, scaling and translation (RST) attacks is proposed. Based on the spread spectrum, the watermark is modulated before embedding. The log-polar mapped discrete fourier transform (LPM-DFT) magnitude of a disk, a part of the origin image, constitutes the RST-invariant domain, where the origin of the LPM is the center of the disk and the sampling rates of the LPM are constant. After the middle frequency band of LPM-DFT magnitude, namely the watermark-embedding domain, is grouped according to the watermark length, the watermark is embedded by adjusting the difference between the two sub-region energy in each group. To improve the imperceptibility, the watermark-embedding domain is shuffled before embedding and the watermark is not embedded directly into the watermark-embedding domain. In watermark detection procedure, neither the original image nor any knowledge about the distortions is required. Experimental results show that the proposed scheme is very robust against RST distortion and common image processing attacks.

  13. Causes of blindness among adult Yemenis: A Hospital-based study

    Directory of Open Access Journals (Sweden)

    Al-Akily Saleh

    2008-01-01

    Full Text Available Purpose: This hospital-based retrospective study was aimed to assess the causes of blindness among adults aged 17 years and over who attended a teaching eye hospital in Yemen. Methods: The case notes of 3845 consecutive new patients over 12 months attending Ibn Al-Haitham Eye Center which is affiliated to the University of Science and Technology in Sana′a (the capital of Yemen were retrieved and analysed. Data collected included age, gender, chief complaint and complete eye examination. Results: 7.7 percent (296 were uniocularly blind and 11.2 percent (432 were binocularly blind (best corrected visual acuity < 3/60 in the better eye. The leading causes of uniocular blindness were cataract, trauma related ocular complications, corneal opacity, amblyopia and glaucoma. Binocular blindness was mainly due to cataract, glaucoma, diabetic retinopathy, age related macular degeneration and corneal opacity. Conclusions: These data imply that the preliminary results give us some insight about the magnitude of the problem of blindness in Yemen while awaiting a national survey on the prevalence and causes of blindness. Cataract was found to be the main cause of unilateral and bilateral blindness and this will require surgical relief, either in public hospitals, private hospitals and clinics, or in eye camps. Trauma related ocular complications were found to be the second most common cause of uniocular blindness. Health education, implementing work safety measures and bringing ophthalmological care to the doorstep of underprivileged rural community will improve their level of awareness.

  14. Joint ICA-Based Blind Detection and Parameter Assessment in DS-CDMA Systems

    Directory of Open Access Journals (Sweden)

    Mohammad Eslami

    2011-09-01

    Full Text Available In this study, blind code extraction of Direct Sequence Code Division Multiple Access (DS-CDMA signals is considered, based on Independent Component Analysis (ICA method. In order to distinguish between correct and incorrect extracted codes, to estimate the number of active users and also to determine the quality of detection along with the ICA based blind detection procedure, some propositions are defined. These propositions are used to improve the performance of the ICA blind detection based method. Then, in order to analyze the proposed criteria, Principle Component Analysis (PCA and Gaussian Mixture Model (GMM are employed. Experimental results illustrate that the achieved performance of the defined criteria.

  15. Blindness in a 25-Year Follow-up of a Population-Based Cohort of Danish Type 1 Diabetic Patients

    DEFF Research Database (Denmark)

    Grauslund, Jakob; Green, Anders; Sjølie, Anne Katrin

    2009-01-01

    PURPOSE: To assess the long-term incidence of blindness and to evaluate risk factors for blindness in a population-based cohort of type 1 diabetic patients. DESIGN: Retrospective cohort study. PARTICIPANTS: A population-based cohort of 573 type 1 diabetic patients, all of whom participated...... to the subsequent development of blindness. Blindness was defined as present in patients who were registered as members of the Danish Association of the Blind between baseline and January 2007. The Danish Association of the Blind is a voluntary organization open for all patients with a best-corrected visual acuity...

  16. BLIND ADAPTIVE MULTIUSER DETECTION BASED ON A CONSTRAINED MMSE CRITERION

    Institute of Scientific and Technical Information of China (English)

    Tian Libin; Chen Fangjiong; Wei Gang

    2004-01-01

    The proposed blind adaptive multiuser detector utilizes the signature waveform and time information of the desired user. With each received sample vector, the proposed algorithm updates the detector and gives the symbol estimate in the current time slot. Such property facilitates it to track time-varying channels.

  17. A Blind Equalizer Based on Unsupervised Gaussian Cluster Formation with an Adaptive Non—Linearity

    Institute of Scientific and Technical Information of China (English)

    LiuHanyu; TongWen; 等

    1997-01-01

    In this paper we present a blind equalizer algorithm based on an unsupervised Gaussian cluster formation technique with an optimized gradient adaptive step-size to update the equalizer coefficients.The novelty of this work lies in the optimization of the nonlinearity of the cluster formation used to achieve an optimal soft decision.The proposed iterative procedure combined with the variable step-size gradient-based adaptation,significantly accelerates the convergence speed of the blind equalization.The advantages of the proposed equalization techniques are illustrated by simulation.Simulation results obtained are compared with the Sato and Godard blind equalizers.

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

    Science.gov (United States)

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

    2013-08-01

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

  19. A sessional blind signature based on quantum cryptography

    Science.gov (United States)

    Khodambashi, Siavash; Zakerolhosseini, Ali

    2014-01-01

    In this paper, we present a sessional blind signature protocol whose security is guaranteed by fundamental principles of quantum physics. It allows a message owner to get his message signed by an authorized signatory. However, the signatory is not capable of reading the message contents and everyone can verify authenticity of the message. For this purpose, we took advantage of a sessional signature as well as quantum entangled pairs which are generated with respect to it in our proposed protocol. We describe our proposed blind signature through an example and briefly discuss about its unconditional security. Due to the feasibility of the protocol, it can be widely employed for e-payment, e-government, e-business and etc.

  20. Unilateral childhood blindness: a hospital-based study in Yaoundé, Cameroon

    Directory of Open Access Journals (Sweden)

    André; Omgbwa Eballe

    2009-08-01

    Full Text Available André Omgbwa Eballe1, Emilienne Epée2, Godefroy Koki2, Lucienne Bella2, Côme Ebana Mvogo21Faculty of Medicine and Pharmaceutical Sciences, University of Douala, Douala, Cameroon; 2Faculty of Medicine and Biomedical Sciences, University of Yaoundé I, Yaoundé, CameroonIntroduction: We performed an analytic and prospective study over a period of 12 months from January 2nd to December 31st, 2008, at the Gynaeco-Obstetric and Paediatric Hospital of Yaoundé, Cameroon. Our aim was to determine the prevalence and causes of unilateral blindness in school children aged 6 to 15 years.Results: Among the 1,266 children aged 6 to 15 years who were recruited, 60 presented with unilateral blindness (4.7%: 42 boys (6.96% and 18 girls (2.71%. The mean age was 10.15 ± 3.4 years. In patients with unilateral blindness, 65% was due to ocular trauma.Discussion: The hospital-based prevalence of unilateral blindness in children is relatively high and ocular trauma is the leading etiology.Conclusion: Unilateral blindness in school children is avoidable and its incidence could be markedly reduced by emphasizing an information strategy and education based on prevention of ocular trauma. Early management of nontraumatic diseases such as infantile glaucoma and some tumors could improve outcome and avoid blindness.Keywords: unilateral blindness, ocular trauma, prevalence, education

  1. Online blind source separation based on joint diagonalization

    Institute of Scientific and Technical Information of China (English)

    Li Ronghua; Zhou Guoxu; Fang Zuyuan; Xie Shengli

    2009-01-01

    A now algorithm is proposed for joint diagonalization. With a modified objective function, the now algorithm not only excludes trivial and unbalanced solutions successfully, but is also easily optimized. In addition, with the new objective function, the proposed algorithm can work well in online blind source separation (BSS) for the first time, although this family of algorithms is always thought to be valid only in batch-mode BSS by far. Simulations show that it is a very competitive joint diagonalization algorithm.

  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. CONSTRUCTION OF PROXY BLIND SIGNATURE SCHEME BASED ON MULTI-LINEAR TRANSFORM

    Institute of Scientific and Technical Information of China (English)

    Zhao Zemao; Liu Fengyu

    2004-01-01

    A general method of constructing proxy blind signature is proposed based on multilinear transform. Based on this method, the four proxy blind signature schemes are correspondently generated with four different signature equations, and each of them has four forms of variations of signs. Hence there are sixteen signatures in all, and all of them are proxy stronglyblind signature schemes. Furthermore, the two degenerated situations of multi-linear transform are discussed. Their corresponding proxy blind signature schemes are shown, too. But some schemes come from one of these degenerate situations are proxy weakly-blind signature scheme.The security for proposed scheme is analyzed in details. The results indicate that these signature schemes have many good properties such as unforgeability, distinguish-ability of proxy signature,non-repudiation and extensive value of application etc.

  4. Risk Analysis on Groundwater Resources Carrying Capacity Based on Blind Number Theory

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ji; YU Sujun

    2007-01-01

    Blind numbers of evaluation indices about groundwater resources carrying capacity are defined from the concomitancy of randomness, fuzziness, grey property and unascertainment of groundwater system.Based on fuzzy theory, a comprehensive evaluation model on groundwaterresources carrying capacity is constructed with blind information. Then arisk assessment model of surcharge about groundwater resources carryingcapacity is established on blind reliability theory. The probable value"*"'matrix of fuzzy membership degree about carrying capacity corresponding to each judgment level can be obtained with the aid of blind algorithm as well as the subjective reliability "×" matrix. And then a graph of"groundwater carrying capacity v.s. accumulative reliability" can be gained.Based on the graph, fuzzy membership degree of groundwater resourcescarrying capacity to each judgment level under different risk probabilitycan be got. Thus, a comparatively reasonable judgment to groundwaterresources carrying capacity might be obtained, with comprehensive analysis to the state of society, economy technology and ecology.

  5. A Novel Video Compression Approach Based on Underdetermined Blind Source Separation

    CERN Document Server

    Liu, Jing; Wei, Qi; Yang, Huazhong

    2012-01-01

    This paper develops a new video compression approach based on underdetermined blind source separation. Underdetermined blind source separation, which can be used to efficiently enhance the video compression ratio, is combined with various off-the-shelf codecs in this paper. Combining with MPEG-2, video compression ratio could be improved slightly more than 33%. As for combing with H.264, 4X~12X more compression ratio could be achieved with acceptable PSNR, according to different kinds of video sequences.

  6. Design and Development of a Mobile Sensor Based the Blind Assistance Wayfinding System

    Science.gov (United States)

    Barati, F.; Delavar, M. R.

    2015-12-01

    The blind and visually impaired people are facing a number of challenges in their daily life. One of the major challenges is finding their way both indoor and outdoor. For this reason, routing and navigation independently, especially in urban areas are important for the blind. Most of the blind undertake route finding and navigation with the help of a guide. In addition, other tools such as a cane, guide dog or electronic aids are used by the blind. However, in some cases these aids are not efficient enough in a wayfinding around obstacles and dangerous areas for the blind. As a result, the need to develop effective methods as decision support using a non-visual media is leading to improve quality of life for the blind through their increased mobility and independence. In this study, we designed and implemented an outdoor mobile sensor-based wayfinding system for the blind. The objectives of this study are to guide the blind for the obstacle recognition and the design and implementation of a wayfinding and navigation mobile sensor system for them. In this study an ultrasonic sensor is used to detect obstacles and GPS is employed for positioning and navigation in the wayfinding. This type of ultrasonic sensor measures the interval between sending waves and receiving the echo signals with respect to the speed of sound in the environment to estimate the distance to the obstacles. In this study the coordinates and characteristics of all the obstacles in the study area are already stored in a GIS database. All of these obstacles were labeled on the map. The ultrasonic sensor designed and constructed in this study has the ability to detect the obstacles in a distance of 2cm to 400cm. The implementation and the results obtained from the interview of a number of blind persons who employed the sensor verified that the designed mobile sensor system for wayfinding was very satisfactory.

  7. DESIGN AND DEVELOPMENT OF A MOBILE SENSOR BASED THE BLIND ASSISTANCE WAYFINDING SYSTEM

    Directory of Open Access Journals (Sweden)

    F. Barati

    2015-12-01

    Full Text Available The blind and visually impaired people are facing a number of challenges in their daily life. One of the major challenges is finding their way both indoor and outdoor. For this reason, routing and navigation independently, especially in urban areas are important for the blind. Most of the blind undertake route finding and navigation with the help of a guide. In addition, other tools such as a cane, guide dog or electronic aids are used by the blind. However, in some cases these aids are not efficient enough in a wayfinding around obstacles and dangerous areas for the blind. As a result, the need to develop effective methods as decision support using a non-visual media is leading to improve quality of life for the blind through their increased mobility and independence. In this study, we designed and implemented an outdoor mobile sensor-based wayfinding system for the blind. The objectives of this study are to guide the blind for the obstacle recognition and the design and implementation of a wayfinding and navigation mobile sensor system for them. In this study an ultrasonic sensor is used to detect obstacles and GPS is employed for positioning and navigation in the wayfinding. This type of ultrasonic sensor measures the interval between sending waves and receiving the echo signals with respect to the speed of sound in the environment to estimate the distance to the obstacles. In this study the coordinates and characteristics of all the obstacles in the study area are already stored in a GIS database. All of these obstacles were labeled on the map. The ultrasonic sensor designed and constructed in this study has the ability to detect the obstacles in a distance of 2cm to 400cm. The implementation and the results obtained from the interview of a number of blind persons who employed the sensor verified that the designed mobile sensor system for wayfinding was very satisfactory.

  8. 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.

  9. Novel Blind Robust Watermarking Based on Chaotic Mixing

    Institute of Scientific and Technical Information of China (English)

    王东建; 蒋铃鸽; 何晨; 冯国瑞

    2004-01-01

    This paper proposed a novel blind robust watermarking scheme. Multi-bits watermark is embedded in the chaotic mixed image blocks. Energy of the watermark is spread to all region of the blocks instead of some individual pixels, which entitles the watermark with imperceptibility and high robustness. A class of 1-D Markov chaotic maps is employed to perform image block mixing and watermark encryption ensures security of the system.To prove the validity of this proposed scheme, some objective comparisons with the popular spread spectrum scheme were also presented. The simulation results show that this scheme can survive processing such as high-ratio JPEG compression, Gaussian noise pollution and histogram equalization.

  10. Voice-based assessments of trustworthiness, competence, and warmth in blind and sighted adults.

    Science.gov (United States)

    Oleszkiewicz, Anna; Pisanski, Katarzyna; Lachowicz-Tabaczek, Kinga; Sorokowska, Agnieszka

    2017-06-01

    The study of voice perception in congenitally blind individuals allows researchers rare insight into how a lifetime of visual deprivation affects the development of voice perception. Previous studies have suggested that blind adults outperform their sighted counterparts in low-level auditory tasks testing spatial localization and pitch discrimination, as well as in verbal speech processing; however, blind persons generally show no advantage in nonverbal voice recognition or discrimination tasks. The present study is the first to examine whether visual experience influences the development of social stereotypes that are formed on the basis of nonverbal vocal characteristics (i.e., voice pitch). Groups of 27 congenitally or early-blind adults and 23 sighted controls assessed the trustworthiness, competence, and warmth of men and women speaking a series of vowels, whose voice pitches had been experimentally raised or lowered. Blind and sighted listeners judged both men's and women's voices with lowered pitch as being more competent and trustworthy than voices with raised pitch. In contrast, raised-pitch voices were judged as being warmer than were lowered-pitch voices, but only for women's voices. Crucially, blind and sighted persons did not differ in their voice-based assessments of competence or warmth, or in their certainty of these assessments, whereas the association between low pitch and trustworthiness in women's voices was weaker among blind than sighted participants. This latter result suggests that blind persons may rely less heavily on nonverbal cues to trustworthiness compared to sighted persons. Ultimately, our findings suggest that robust perceptual associations that systematically link voice pitch to the social and personal dimensions of a speaker can develop without visual input.

  11. Acoustic diagnosis of mechanical fault feature based on reference signal frequency domain semi-blind extraction

    Directory of Open Access Journals (Sweden)

    Zeguang YI

    2015-08-01

    Full Text Available Aiming at fault diagnosis problems caused by complex machinery parts, serious background noises and the application limitations of traditional blind signal processing algorithm to the mechanical acoustic signal processing, a failure acoustic diagnosis based on reference signal frequency domain semi-blind extraction is proposed. Key technologies are introduced: Based on frequency-domain blind deconvolution algorithm, the artificial fish swarm algorithm which is good for global optimization is used to construct improved multi-scale morphological filters which is applicable to mechanical failure in order to weaken the background noises; combining the structural parameters of parts to build a reference signal, complex components blind separation is carried out on the signals after noise reduction paragraph by paragraph by reference signal unit semi-blind extraction algorithm; then the improved KL-distance of complex independent components is employed as distance measure to resolve the permutation, and finally the mechanical fault characteristic signals are extracted and separated. The actual acoustic diagnosis of rolling bearing fault in sound field environment results proves the effectiveness of this algorithm.

  12. Improved system blind identification based on second-order cyclostationary statistics: A group delay approach

    Indian Academy of Sciences (India)

    P V S Giridhar; S V Narasimhan

    2000-04-01

    An improved system blind identification method based on second-order cyclostationary statistics and the properties of group delay, has been proposed. This is achieved by applying a correction to the estimated phase (by the spectral correlation density of the system output) for the poles, in the group delay domain. The results indicate a significant improvement in system blind identification, in terms of root mean square error. Depending upon the signal-to-noise ratio, the improvement in percentage normalized mean square error ranges between 20 and 50%.

  13. An ICA and EC based approach for blind equalization and channel parameter estimation

    Institute of Scientific and Technical Information of China (English)

    何振亚; 刘琚; 杨绿溪; 蔚承建

    2000-01-01

    A new on-line blind equalization approach is proposed. The approach combines over-sampling technique with independent component analysis (ICA) neural network and can give equalized output on-line employing only the received signal. Based on the fourth-order cumulants and the characteristic of the linear system, the parameters of original channel are also estimated using evolutionary computation (EC). Compared to traditional equalization methods, the proposed algorithm is of simple architecture, does not need learning sequences apart from the observation, and can achieve both blind equalization and system identification. Computer simulations show good performance.

  14. An ICA and EC based approach for blind equalization and channel parameter estimation

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A new on-line blind equalization approach is proposed. The approach combines over-sampling technique with independent component analysis (ICA)neural network and can give equalized output on-line employing only the received signal. Based on the fourth-order cumulants and the characteristic of the linear system, the parameters of original channel are also estimated using evolutionary computation(EC).Compared to traditional equalization methods, the proposed algorithm is of simple architecture, does not need learning sequences apart from the observation, and can achieve both blind equalization and system identification. Computer simulations show good performance.

  15. 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.

  16. A novel blinding digital watermark algorithm based on lab color space

    Science.gov (United States)

    Dong, Bing-feng; Qiu, Yun-jie; Lu, Hong-tao

    2010-02-01

    It is necessary for blinding digital image watermark algorithm to extract watermark information without any extra information except the watermarked image itself. But most of the current blinding watermark algorithms have the same disadvantage: besides the watermarked image, they also need the size and other information about the original image when extracting the watermark. This paper presents an innovative blinding color image watermark algorithm based on Lab color space, which does not have the disadvantages mentioned above. This algorithm first marks the watermark region size and position through embedding some regular blocks called anchor points in image spatial domain, and then embeds the watermark into the image. In doing so, the watermark information can be easily extracted after doing cropping and scale change to the image. Experimental results show that the algorithm is particularly robust against the color adjusting and geometry transformation. This algorithm has already been used in a copyright protecting project and works very well.

  17. Comment Fail-Stop Blind Signature Scheme Design Based on Pairings

    Institute of Scientific and Technical Information of China (English)

    HU Xiaoming; HUANG Shangteng

    2006-01-01

    Fail-stop signature schemes provide security for a signer against forgeries of an enemy with unlimited computational power by enabling the signer to provide a proof of forgery when a forgery happens. Chang et al proposed a robust fail-stop blind signature scheme based on bilinear pairings. However, in this paper, it will be found that there are several mistakes in Chang et al' fail-stop blind signature scheme. Moreover, it will be pointed out that this scheme doesn' meet the property of a fail-stop signature: unconditionally secure for a signer. In Chang et al' scheme, a forger can forge a valid signature that can' be proved by a signer using the "proof of forgery". The scheme also doesn' possess the unlinkability property of a blind signature.

  18. CONFAC Decomposition Approach to Blind Identification of Underdetermined Mixtures Based on Generating Function Derivatives

    NARCIS (Netherlands)

    de Almeida, Andre L. F.; Luciani, Xavier; Stegeman, Alwin; Comon, Pierre

    2012-01-01

    This work proposes a new tensor-based approach to solve the problem of blind identification of underdetermined mixtures of complex-valued sources exploiting the cumulant generating function (CGF) of the observations. We show that a collection of second-order derivatives of the CGF of the observation

  19. Measurement-Based and Universal Blind Quantum Computation

    Science.gov (United States)

    Broadbent, Anne; Fitzsimons, Joseph; Kashefi, Elham

    Measurement-based quantum computation (MBQC) is a novel approach to quantum computation where the notion of measurement is the main driving force of computation. This is in contrast with the more traditional circuit model which is based on unitary operation. We review here the mathematical model underlying MBQC and the first quantum cryptographic protocol designed using the unique features of MBQC.

  20. an Efficient Blind Signature Scheme based on Error Correcting Codes

    Directory of Open Access Journals (Sweden)

    Junyao Ye

    Full Text Available Cryptography based on the theory of error correcting codes and lattices has received a wide attention in the last years. Shor`s algorithm showed that in a world where quantum computers are assumed to exist, number theoretic cryptosystems are insecure. The ...

  1. Voxel-Based Morphometric Study on Chinese Blind Men's Brain Structure

    Institute of Scientific and Technical Information of China (English)

    YANG Chun-lan; PAN Wen-ju; ZHENG Lian

    2007-01-01

    Many studies have shown the functional relevance of cross-modal plasticity in blind men.In order to study the changes of their brain structure,voxel-based morphometry (VBM) methods are used.The regional gray matter (GM) and white matter (WM) concentrations of magnetic resonance (MR) images from 11 blind people and 9 sighted control subjects are compared using standard VBM.Optimized VBM is also discussed to measure the absolute local volume of GM or WM.Consistent results are achieved by statistical analysis with these methods.There are distinct differences not only in visual cortex but also the sensory area,auditory area and motor area.GM concentrations in blind men significantly decreased in Brodmann 7 and 22.While in Brodmann 18 and 19,GM concentration increased.GM volumes decreased in Brodmann 3,4,6,9 and 45.On the other hand,both WM concentration and volume increased in Brodmann 7.These results suggest that early visual deprivation can lead to changes in the brain structural anatomy which is consistent with the cortical cross-modal reorganization found by functional imaging.It may help to discover the relationship between the brain structural anatomy and the brain functional data of blind men at a macroscopic level from neuroimaging perspective.

  2. Novel Blind Recognition Algorithm of Frame Synchronization Words Based on Soft-Decision in Digital Communication Systems.

    Directory of Open Access Journals (Sweden)

    Jiangyi Qin

    Full Text Available A novel blind recognition algorithm of frame synchronization words is proposed to recognize the frame synchronization words parameters in digital communication systems. In this paper, a blind recognition method of frame synchronization words based on the hard-decision is deduced in detail. And the standards of parameter recognition are given. Comparing with the blind recognition based on the hard-decision, utilizing the soft-decision can improve the accuracy of blind recognition. Therefore, combining with the characteristics of Quadrature Phase Shift Keying (QPSK signal, an improved blind recognition algorithm based on the soft-decision is proposed. Meanwhile, the improved algorithm can be extended to other signal modulation forms. Then, the complete blind recognition steps of the hard-decision algorithm and the soft-decision algorithm are given in detail. Finally, the simulation results show that both the hard-decision algorithm and the soft-decision algorithm can recognize the parameters of frame synchronization words blindly. What's more, the improved algorithm can enhance the accuracy of blind recognition obviously.

  3. Novel Blind Recognition Algorithm of Frame Synchronization Words Based on Soft-Decision in Digital Communication Systems.

    Science.gov (United States)

    Qin, Jiangyi; Huang, Zhiping; Liu, Chunwu; Su, Shaojing; Zhou, Jing

    2015-01-01

    A novel blind recognition algorithm of frame synchronization words is proposed to recognize the frame synchronization words parameters in digital communication systems. In this paper, a blind recognition method of frame synchronization words based on the hard-decision is deduced in detail. And the standards of parameter recognition are given. Comparing with the blind recognition based on the hard-decision, utilizing the soft-decision can improve the accuracy of blind recognition. Therefore, combining with the characteristics of Quadrature Phase Shift Keying (QPSK) signal, an improved blind recognition algorithm based on the soft-decision is proposed. Meanwhile, the improved algorithm can be extended to other signal modulation forms. Then, the complete blind recognition steps of the hard-decision algorithm and the soft-decision algorithm are given in detail. Finally, the simulation results show that both the hard-decision algorithm and the soft-decision algorithm can recognize the parameters of frame synchronization words blindly. What's more, the improved algorithm can enhance the accuracy of blind recognition obviously.

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

    Science.gov (United States)

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

    2014-11-01

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

  5. A blind video watermarking scheme based on ICA and shot segmentation

    Institute of Scientific and Technical Information of China (English)

    SUN Jiande; LIU Ju

    2006-01-01

    Video watermark is the main method to protect the copyright of digital video. In this paper, a blind video watermarking scheme based on independent component analysis (ICA) and shot segmentation is presented. In this scheme, the global histogram comparison approach is used to segment the video, and ICA is performed on each obtained segment to get its independent component frames (ICFs). The copyright information is embedded into the principal independent component frames (PICFs) according to the single watermark embedding (SWE) scheme. The content-based shot segmentation for video sequences is used here to improve the robustness to temporal desynchronization. The watermark embedded in PICFs provides better robustness to intra-video collusion attack. And blind detection is achieved by using the SWE scheme. The simulations show the feasibility and validity of this scheme. It can resist most of the common frame-based and video-based attacks. The watermark can be detected blindly. And it is robust to temporal desynchronization and intra-video collusion.

  6. 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.

  7. 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.

  8. Blind adaptive MMSE equalization of underwater acoustic channels based on the linear prediction method

    Science.gov (United States)

    Zhang, Yinbing; Zhao, Junwei; Guo, Yecai; Li, Jinming

    2011-03-01

    The problem of blind adaptive equalization of underwater single-input multiple-output (SIMO) acoustic channels was analyzed by using the linear prediction method. Minimum mean square error (MMSE) blind equalizers with arbitrary delay were described on a basis of channel identification. Two methods for calculating linear MMSE equalizers were proposed. One was based on full channel identification and realized using RLS adaptive algorithms, and the other was based on the zero-delay MMSE equalizer and realized using LMS and RLS adaptive algorithms, respectively. Performance of the three proposed algorithms and comparison with two existing zero-forcing (ZF) equalization algorithms were investigated by simulations utilizing two underwater acoustic channels. The results show that the proposed algorithms are robust enough to channel order mismatch. They have almost the same performance as the corresponding ZF algorithms under a high signal-to-noise (SNR) ratio and better performance under a low SNR.

  9. Instantaneous Gradient Based Dual Mode Feed-Forward Neural Network Blind Equalization Algorithm

    Directory of Open Access Journals (Sweden)

    Ying Xiao

    2013-01-01

    Full Text Available To further improve the performance of feed-forward neural network blind equalization based on Constant Modulus Algorithm (CMA cost function, an instantaneous gradient based dual mode between Modified Constant Modulus Algorithm (MCMA and Decision Directed (DD algorithm was proposed. The neural network weights change quantity of the adjacent iterative process is defined as instantaneous gradient. After the network converges, the weights of neural network to achieve a stable energy state and the instantaneous gradient would be zero. Therefore dual mode algorithm can be realized by criterion which set according to the instantaneous gradient. Computer simulation results show that the dual mode feed-forward neural network blind equalization algorithm proposed in this study improves the convergence rate and convergence precision effectively, at the same time, has good restart and tracking ability under channel burst interference condition.

  10. 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.

  11. Blind Equalization Based on RLS Algorithm Using Adaptive Forgetting Factor for Underwater Acoustic Channel

    Institute of Scientific and Technical Information of China (English)

    肖瑛; 殷福亮

    2014-01-01

    Blind equalization based on adaptive forgetting factor, recursive least squares (RLS) with constant modulus algorithm (CMA), is investigated. The cost function of CMA is simplified to meet the second norm form to ensure the stability of RLS-CMA, and thus an improved RLS-CMA (RLS-SCMA) is established. To further improve its performance, a new adaptive forgetting factor RLS-SCMA (ARLS-SCMA) is proposed. In ARLS-SCMA, the forgetting factor varies with the output error of the blind equalizer during the iterative process, which leads to a faster convergence rate and a smaller steady-state error. The simulation results prove the effectiveness under the condition of the underwater acoustic channel.

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

    Institute of Scientific and Technical Information of China (English)

    Ratnakar Dash; Pankaj Kumar Sa; Banshidhar Majhi

    2012-01-01

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

  13. 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.

  14. Blind Identification of SIMO Wiener Systems Based on Kernel Canonical Correlation Analysis

    Science.gov (United States)

    Van Vaerenbergh, Steven; Via, Javier; Santamaria, Ignacio

    2013-05-01

    We consider the problem of blind identification and equalization of single-input multiple-output (SIMO) nonlinear channels. Specifically, the nonlinear model consists of multiple single-channel Wiener systems that are excited by a common input signal. The proposed approach is based on a well-known blind identification technique for linear SIMO systems. By transforming the output signals into a reproducing kernel Hilbert space (RKHS), a linear identification problem is obtained, which we propose to solve through an iterative procedure that alternates between canonical correlation analysis (CCA) to estimate the linear parts, and kernel canonical correlation (KCCA) to estimate the memoryless nonlinearities. The proposed algorithm is able to operate on systems with as few as two output channels, on relatively small data sets and on colored signals. Simulations are included to demonstrate the effectiveness of the proposed technique.

  15. 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.

  16. Improvement of a quantum broadcasting multiple blind signature scheme based on quantum teleportation

    Science.gov (United States)

    Zhang, Wei; Qiu, Daowen; Zou, Xiangfu

    2016-06-01

    Recently, a broadcasting multiple blind signature scheme based on quantum teleportation has been proposed for the first time. It is claimed to have unconditional security and properties of quantum multiple signature and quantum blind signature. In this paper, we analyze the security of the protocol and show that each signatory can learn the signed message by a single-particle measurement and the signed message can be modified at random by any attacker according to the scheme. Furthermore, there are some participant attacks and external attacks existing in the scheme. Finally, we present an improved scheme and show that it can resist all of the mentioned attacks. Additionally, the secret keys can be used again and again, making it more efficient and practical.

  17. A MUSIC-Based Algorithm for Blind User Identification in Multiuser DS-CDMA

    Directory of Open Access Journals (Sweden)

    M. Reza Soleymani

    2005-04-01

    Full Text Available A blind scheme based on multiple-signal classification (MUSIC algorithm for user identification in a synchronous multiuser code-division multiple-access (CDMA system is suggested. The scheme is blind in the sense that it does not require prior knowledge of the spreading codes. Spreading codes and users' power are acquired by the scheme. Eigenvalue decomposition (EVD is performed on the received signal, and then all the valid possible signature sequences are projected onto the subspaces. However, as a result of this process, some false solutions are also produced and the ambiguity seems unresolvable. Our approach is to apply a transformation derived from the results of the subspace decomposition on the received signal and then to inspect their statistics. It is shown that the second-order statistics of the transformed signal provides a reliable means for removing the false solutions.

  18. Toward a Computer Vision-based Wayfinding Aid for Blind Persons to Access Unfamiliar Indoor Environments.

    Science.gov (United States)

    Tian, Yingli; Yang, Xiaodong; Yi, Chucai; Arditi, Aries

    2013-04-01

    Independent travel is a well known challenge for blind and visually impaired persons. In this paper, we propose a proof-of-concept computer vision-based wayfinding aid for blind people to independently access unfamiliar indoor environments. In order to find different rooms (e.g. an office, a lab, or a bathroom) and other building amenities (e.g. an exit or an elevator), we incorporate object detection with text recognition. First we develop a robust and efficient algorithm to detect doors, elevators, and cabinets based on their general geometric shape, by combining edges and corners. The algorithm is general enough to handle large intra-class variations of objects with different appearances among different indoor environments, as well as small inter-class differences between different objects such as doors and door-like cabinets. Next, in order to distinguish intra-class objects (e.g. an office door from a bathroom door), we extract and recognize text information associated with the detected objects. For text recognition, we first extract text regions from signs with multiple colors and possibly complex backgrounds, and then apply character localization and topological analysis to filter out background interference. The extracted text is recognized using off-the-shelf optical character recognition (OCR) software products. The object type, orientation, location, and text information are presented to the blind traveler as speech.

  19. Blind ICA detection based on second-order cone programming for MC-CDMA systems

    Science.gov (United States)

    Jen, Chih-Wei; Jou, Shyh-Jye

    2014-12-01

    The multicarrier code division multiple access (MC-CDMA) technique has received considerable interest for its potential application to future wireless communication systems due to its high data rate. A common problem regarding the blind multiuser detectors used in MC-CDMA systems is that they are extremely sensitive to the complex channel environment. Besides, the perturbation of colored noise may negatively affect the performance of the system. In this paper, a new coherent detection method will be proposed, which utilizes the modified fast independent component analysis (FastICA) algorithm, based on approximate negentropy maximization that is subject to the second-order cone programming (SOCP) constraint. The aim of the proposed coherent detection is to provide robustness against small-to-medium channel estimation mismatch (CEM) that may arise from channel frequency response estimation error in the MC-CDMA system, which is modulated by downlink binary phase-shift keying (BPSK) under colored noise. Noncoherent demodulation schemes are preferable to coherent demodulation schemes, as the latter are difficult to implement over time-varying fading channels. Differential phase-shift keying (DPSK) is therefore the natural choice for an alternative modulation scheme. Furthermore, the new blind differential SOCP-based ICA (SOCP-ICA) detection without channel estimation and compensation will be proposed to combat Doppler spread caused by time-varying fading channels in the DPSK-modulated MC-CDMA system under colored noise. In this paper, numerical simulations are used to illustrate the robustness of the proposed blind coherent SOCP-ICA detector against small-to-medium CEM and to emphasize the advantage of the blind differential SOCP-ICA detector in overcoming Doppler spread.

  20. Adaptive blind separation of underdetermined mixtures based on sparse component analysis

    Institute of Scientific and Technical Information of China (English)

    YANG ZuYuan; HE ZhaoShui; XIE ShengLi; FU YuLi

    2008-01-01

    The independence priori is very often used in the conventional blind source sepa-ration (BSS). Naturally, independent component analysis (ICA) is also employed to perform BSS very often. However, ICA is difficult to use in some challenging cases, such as underdetermined BSS or blind separation of dependent sources. Recently, sparse component analysis (SCA) has attained much attention because it is theo-retically available for underdetermined BSS and even for blind dependent source separation sometimes. However, SCA has not been developed very sufficiently. Up to now, there are only few existing algorithms and they are also not perfect as well in practice. For example, although Lewicki-Sejnowski's natural gradient for SCA is superior to K-mean clustering, it is just an approximation without rigorously theo-retical basis. To overcome these problems, a new natural gradient formula is pro-posed in this paper. This formula is derived directly from the cost function of SCA through matrix theory. Mathematically, it is more rigorous. In addition, a new and robust adaptive BSS algorithm is developed based on the new natural gradient. Simulations illustrate that this natural gradient formula is more robust and reliable than Lewicki-Sejnowski's gradient.

  1. 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

    position. Then, each candidate position is characterized by a set of features. In addition to exploiting the overall spectral shape, a new set of mask-based features is proposed which aims at characterizing the pattern of the estimated binary mask. The decision stage for detecting a speech source is based...... 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...

  2. A Component-Based Study of the Effect of Diameter on Bond and Anchorage Characteristics of Blind-Bolted Connections.

    Directory of Open Access Journals (Sweden)

    Muhammad Nasir Amin

    Full Text Available Structural hollow sections are gaining worldwide importance due to their structural and architectural advantages over open steel sections. The only obstacle to their use is their connection with other structural members. To overcome the obstacle of tightening the bolt from one side has given birth to the concept of blind bolts. Blind bolts, being the practical solution to the connection hindrance for the use of hollow and concrete filled hollow sections play a vital role. Flowdrill, the Huck High Strength Blind Bolt and the Lindapter Hollobolt are the well-known commercially available blind bolts. Although the development of blind bolts has largely resolved this issue, the use of structural hollow sections remains limited to shear resistance. Therefore, a new modified version of the blind bolt, known as the "Extended Hollo-Bolt" (EHB due to its enhanced capacity for bonding with concrete, can overcome the issue of low moment resistance capacity associated with blind-bolted connections. The load transfer mechanism of this recently developed blind bolt remains unclear, however. This study uses a parametric approach to characterising the EHB, using diameter as the variable parameter. Stiffness and load-carrying capacity were evaluated at two different bolt sizes. To investigate the load transfer mechanism, a component-based study of the bond and anchorage characteristics was performed by breaking down the EHB into its components. The results of the study provide insight into the load transfer mechanism of the blind bolt in question. The proposed component-based model was validated by a spring model, through which the stiffness of the EHB was compared to that of its components combined. The combined stiffness of the components was found to be roughly equivalent to that of the EHB as a whole, validating the use of this component-based approach.

  3. 193 nm deep-ultraviolet solar-blind cubic boron nitride based photodetectors

    Science.gov (United States)

    Soltani, A.; Barkad, H. A.; Mattalah, M.; Benbakhti, B.; De Jaeger, J.-C.; Chong, Y. M.; Zou, Y. S.; Zhang, W. J.; Lee, S. T.; BenMoussa, A.; Giordanengo, B.; Hochedez, J.-F.

    2008-02-01

    Deep-ultraviolet (DUV) solar-blind photodetectors based on high-quality cubic boron nitride (cBN) films with a metal/semiconductor/metal configuration were fabricated. The design of interdigitated circular electrodes enables high homogeneity of electric field between pads. The DUV photodetectors present a peak responsivity at 180nm with a very sharp cutoff wavelength at 193nm and a visible rejection ratio (180 versus 250nm) of more than four orders of magnitude. The characteristics of the photodetectors present extremely low dark current, high breakdown voltage, and high responsivity, suggesting that cBN films are very promising for DUV sensing.

  4. High order statistics based blind deconvolution of bi-level images with unknown intensity values.

    Science.gov (United States)

    Kim, Jeongtae; Jang, Soohyun

    2010-06-07

    We propose a novel linear blind deconvolution method for bi-level images. The proposed method seeks an optimal point spread function and two parameters that maximize a high order statistics based objective function. Unlike existing minimum entropy deconvolution and least squares minimization methods, the proposed method requires neither unrealistic assumption that the pixel values of a bi-level image are independently identically distributed samples of a random variable nor tuning of regularization parameters.We demonstrate the effectiveness of the proposed method in simulations and experiments.

  5. BlindNav: A Smartphone Based Navigation System for the Visually Impaired

    Directory of Open Access Journals (Sweden)

    Varsha Varadarajan

    2014-04-01

    Full Text Available Navigating in an indoor building and finding path to common locations is one of the primary concerns for visually challenged people. When the blind or visually impaired find themselves in an area they are not familiar with, they feel lost and their safety is at great risk. Current systems do not function in GPS-denied indoor environments and only do identification of particular landmarks encountered by user. As an attempt to address this problem, we present an indoor navigation system based on WiFi strength calculation which is easy to use and highly efficient.

  6. 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.

  7. Blinded double reading yields a higher programme sensitivity than non-blinded double reading at digital screening mammography: a prospected population based study in the south of The Netherlands

    NARCIS (Netherlands)

    Klompenhouwer, E.G.; Voogd, A.C.; Heeten, GJ. den; Strobbe, L.J.A.; Haan, A.F.J. de; Wauters, C.A.; Broeders, M.J.; Duijm, L.E.M.

    2015-01-01

    PURPOSE: To prospectively determine the screening mammography outcome at blinded and non-blinded double reading in a biennial population based screening programme in the south of the Netherlands. METHODS: We included a consecutive series of 87,487 digital screening mammograms, obtained between July

  8. A Hospital Based Clinical Study on Corneal Blindness in a Tertiary Eye Care Centre in North Telangana

    Directory of Open Access Journals (Sweden)

    Raghu Veladanda

    2016-04-01

    Full Text Available Background: Worldwide there are nearly 2.7 million blind people due to corneal disease which is a major causes of blindness in the world today and remains second only to cataract. Aim & Objective: The present hospital based retrospective study was undertaken to estimate the prevalence of corneal blindness in patients attending tertiary eye care center in Chalmeda Anand Rao Institute of Medical Sciences, Karimnagar. Material and Methods: A hospital-based study was conducted over a period of 1 year from August 2014 to August 2015. Participants were patients attending outpatient department of Chalmeda Anand Rao Institute of Medical Sciences. Detailed history was taken and comprehensive ocular examination including Snellen E-chart for visual acuity, slit lamp bio microscopy, contact tonometry, posterior segment evaluation through B-scan and dilated retinal evaluation when indicated was performed at out patient department. Results: Overall, 33,566 patients were examined. Proportion of corneal blindness was 3.9% (CI-95% 3.6% - 4.3%. The proportion increased with age in elderly patients (5.7% and was higher among the females (5.2% compared to males (2.8%. The most common cause of corneal blindness in our study was ocular trauma which was 59.5%. Conclusion: The study ?findings demonstrate that currently ocular trauma, corneal ulceration, infectious keratitis, postsurgical bullous keratopathy, and corneal degenerations are responsible for the major burden of corneal blindness among the patients attending outpatient department.

  9. 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.

  10. Receiver-channel based adaptive blind equalization approach for GPS dynamic multipath mitigation

    Institute of Scientific and Technical Information of China (English)

    Zhao Yun; Xue Xiaonan; Zhang Tingfei

    2013-01-01

    Aiming at mitigating multipath effect in dynamic global positioning system (GPS) satellite navigation applications,an approach based on channel blind equalization and real-time recursive least square (RLS) algorithm is proposed,which is an application of the wireless communication channel equalization theory to GPS receiver tracking loops.The blind equalization mechanism builds upon the detection of the correlation distortion due to multipath channels; there-fore an increase in the number of correlator channels is required compared with conventional GPS receivers.An adaptive estimator based on the real-time RLS algorithm is designed for dynamic estimation of multipath channel response.Then,the code and carrier phase receiver tracking errors are compensated by removing the estimated multipath components from the correlators' outputs.To demonstrate the capabilities of the proposed approach,this technique is integrated into a GPS software receiver connected to a navigation satellite signal simulator,thus simulations under controlled dynamic multipath scenarios can be carried out.Simulation results show that in a dynamic and fairly severe multipath environment,the proposed approach achieves simultaneously instantaneous accurate multipath channel estimation and significant multipath tracking errors reduction in both code delay and carrier phase.

  11. Remote heartbeat signal detection from visible spectrum recordings based on blind deconvolution

    Science.gov (United States)

    Kaur, Balvinder; Moses, Sophia; Luthra, Megha; Ikonomidou, Vasiliki N.

    2016-05-01

    While recent advances have shown that it is possible to acquire a signal equivalent to the heartbeat from visual spectrum video recordings of the human skin, extracting the heartbeat's exact timing information from it, for the purpose of heart rate variability analysis, remains a challenge. In this paper, we explore two novel methods to estimate the remote cardiac signal peak positions, aiming at a close representation of the R-peaks of the ECG signal. The first method is based on curve fitting (CF) using a modified filtered least mean square (LMS) optimization and the second method is based on system estimation using blind deconvolution (BDC). To prove the efficacy of the developed algorithms, we compared results obtained with the ground truth (ECG) signal. Both methods achieved a low relative error between the peaks of the two signals. This work, performed under an IRB approved protocol, provides initial proof that blind deconvolution techniques can be used to estimate timing information of the cardiac signal closely correlated to the one obtained by traditional ECG. The results show promise for further development of a remote sensing of cardiac signals for the purpose of remote vital sign and stress detection for medical, security, military and civilian applications.

  12. The safe zone for blinded sternal interventions based on CT evaluation of midline congenital sternal foramina

    Energy Technology Data Exchange (ETDEWEB)

    Boruah, Deb K.; Dhingani, Dhaval D.; Achar, Shashidhar; Augustine, Antony; Mahanta, Kangkana [Assam Medical College and Hospital, Department of Radio-diagnosis, Dibrugarh, Assam (India); Prakash, Arjun [NIMHANS, Department of Radio-diagnosis, Bangalore, Karnataka (India); Yadav, Rajnikant R. [Sanjay Gandhi Post Graduate Institute and Medical Sciences, Department of Radio-diagnosis, Lucknow (India)

    2016-12-15

    The aim of this study was to evaluate the safe zone for performing blind sternal procedures based on computed tomography (CT) evaluation of congenital midline sternal foramina using multidetector computed tomography (MDCT). This retrospective study was carried out on 1,180 patients who underwent MDCT of the thorax from March 2015 to February 2016. The MDCT images were evaluated in axial and reformatted planes. Morphometry and prevalence of midline congenital sternal foramina (SF) and manubrio-foraminal distance (MFD) were evaluated. The safe zone was defined for a blinded intervention, based on palpable anatomical landmarks. Data were presented in terms of percentage, mean ± standard deviation and calculations were carried out using Microsoft Excel. The prevalence of SF in our study sample was 11.6 %. The majority of SF were located in a typical position in the lower sternal body at the level of fifth costo-chondral junction (CCJ) in 108 patients (78.8 %). The structure directly beneath the SF was mediastinal fat in 73 patients (53.3 %), followed by anterior pericardium in 44 patients (32.1 %) and lung parenchyma in 20 patients (14.6 %). The mean MFD in our study population was 11.90 ± 1.31 cm. Sternal interventions should be avoided at the level of fourth to sixth CCJ, which is considered the danger zone. An intervention at the fourth to sixth CCJ may lead to disastrous consequences in patients who have SF. (orig.)

  13. A blind deconvolution method for ground based telescopes and Fizeau interferometers

    CERN Document Server

    Prato, M; Bonettini, S; Rebegoldi, S; Bertero, M; Boccacci, P

    2015-01-01

    In the case of ground-based telescopes equipped with adaptive optics systems, the point spread function (PSF) is only poorly known or completely unknown. Moreover, an accurate modeling of the PSF is in general not available. Therefore in several imaging situations the so-called blind deconvolution methods, aiming at estimating both the scientific target and the PSF from the detected image, can be useful. A blind deconvolution problem is severely ill-posed and, in order to reduce the extremely large number of possible solutions, it is necessary to introduce sensible constraints on both the scientific target and the PSF. In a previous paper we proposed a sound mathematical approach based on a suitable inexact alternating minimization strategy for minimizing the generalized Kullback-Leibler divergence, assuring global convergence. In the framework of this method we showed that an important constraint on the PSF is the upper bound which can be derived from the knowledge of its Strehl ratio. The efficacy of the ap...

  14. A Novel Damage Detection Algorithm using Time-Series Analysis-Based Blind Source Separation

    Directory of Open Access Journals (Sweden)

    A. Sadhu

    2013-01-01

    Full Text Available In this paper, a novel damage detection algorithm is developed based on blind source separation in conjunction with time-series analysis. Blind source separation (BSS, is a powerful signal processing tool that is used to identify the modal responses and mode shapes of a vibrating structure using only the knowledge of responses. In the proposed method, BSS is first employed to estimate the modal response using the vibration measurements. Time-series analysis is then performed to characterize the mono-component modal responses and successively the resulting time-series models are utilized for one-step ahead prediction of the modal response. With the occurrence of newer measurements containing the signature of damaged system, a variance-based damage index is used to identify the damage instant. Once the damage instant is identified, the damaged and undamaged modal parameters of the system are estimated in an adaptive fashion. The proposed method solves classical damage detection issues including the identification of damage instant, location as well as the severity of damage. The proposed damage detection algorithm is verified using extensive numerical simulations followed by the full scale study of UCLA Factor building using the measured responses under Parkfield earthquake.

  15. 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.

  16. A blind watermarking algorithm for 3D mesh models based on vertex curvature

    Institute of Scientific and Technical Information of China (English)

    Yong-zhao ZHAN; Yan-ting LI; Xin-yu WANG; Yi QIAN

    2014-01-01

    We propose a robust blind watermarking algorithm for three-dimensional (3D) mesh models based on vertex cur-vature to maintain good robustness and improve visual masking in 3D mesh models. In the embedding process, by using the local window of vertex, the root mean square curvature is calculated for every vertex of the 3D mesh model and an ordered set of fluctuation values is obtained. According to the ordered fluctuation values, the vertices are separated into bins. In each bin the fluctuation values are normalized. Finally, the mean of the root mean square curvature fluctuation values of the vertices in each bin is modulated to embed watermark information. In watermark detection, the algorithm uses a blind watermark extraction technique to extract the watermark information. The experimental results show that the algorithm has a very good performance for visual masking of the embedded model and that it can resist a variety of common attacks such as vertex rearrangement, rotation, trans-lating, uniform scaling, noise, smoothing, quantization, and simplification.

  17. A Wireless Sensor Network Based Personnel Positioning Scheme in Coal Mines with Blind Areas

    Directory of Open Access Journals (Sweden)

    Shaobo Geng

    2010-11-01

    Full Text Available This paper proposes a novel personnel positioning scheme for a tunnel network with blind areas, which compared with most existing schemes offers both low-cost and high-precision. Based on the data models of tunnel networks, measurement networks and mobile miners, the global positioning method is divided into four steps: (1 calculate the real time personnel location in local areas using a location engine, and send it to the upper computer through the gateway; (2 correct any localization errors resulting from the underground tunnel environmental interference; (3 determine the global three-dimensional position by coordinate transformation; (4 estimate the personnel locations in the blind areas. A prototype system constructed to verify the positioning performance shows that the proposed positioning system has good reliability, scalability, and positioning performance. In particular, the static localization error of the positioning system is less than 2.4 m in the underground tunnel environment and the moving estimation error is below 4.5 m in the corridor environment. The system was operated continuously over three months without any failures.

  18. A Fair Off-Line Electronic Cash Scheme Based on Restrictive Partially Blind Signature

    Institute of Scientific and Technical Information of China (English)

    王常吉; 吴建平; 段海新

    2004-01-01

    A fair off-line electronic cash scheme was presented based on a provable secure restrictive partially blind signature.The scheme is more efficient than those of previous works as the expiry date and denomination information are embedded in the electronic cash,which alleviates the storage pressure for the bank to check double spending,and the bank need not use different public keys for different coin values,shops and users need not carry a list of bank's public keys to verify in their electronic wallet.The modular exponentiations are reduced for both the user and the bank by letting the trustee publish the public values with different structure as those of previous electronic cash schemes.The scheme security is based on the random oracle model and the decision Diffie-Hellman assumption.The scheme can be easily extended to multi-trustees and multi-banks using threshold cryptography.

  19. 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.

  20. 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.

  1. Enhancement of Twins Fetal ECG Signal Extraction Based on Hybrid Blind Extraction Techniques

    Directory of Open Access Journals (Sweden)

    Ahmed Kareem Abdullah

    2017-07-01

    Full Text Available ECG machines are noninvasive system used to measure the heartbeat signal. It’s very important to monitor the fetus ECG signals during pregnancy to check the heat activity and to detect any problem early before born, therefore the monitoring of ECG signals have clinical significance and importance. For multi-fetal pregnancy case the classical filtering algorithms are not sufficient to separate the ECG signals between mother and fetal. In this paper the mixture consists of mixing from three ECG signals, the first signal is the mother ECG (M-ECG signal, second signal the Fetal-1 ECG (F1-ECG, and third signal is the Fetal-2 ECG (F2-ECG, these signals are extracted based on modified blind source extraction (BSE techniques. The proposed work based on hybridization between two BSE techniques to ensure that the extracted signals separated well. The results demonstrate that the proposed work very efficiently to extract the useful ECG signals

  2. 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.

  3. Voice-based assessments of trustworthiness, competence, and warmth in blind and sighted adults

    OpenAIRE

    Oleszkiewicz, Anna; Pisanski, Katarzyna; Lachowicz-Tabaczek, Kinga; Sorokowska, Agnieszka

    2016-01-01

    The study of voice perception in congenitally blind individuals allows researchers rare insight into how a lifetime of visual deprivation affects the development of voice perception. Previous studies have suggested that blind adults outperform their sighted counterparts in low-level auditory tasks testing spatial localization and pitch discrimination, as well as in verbal speech processing; however, blind persons generally show no advantage in nonverbal voice recognition or discrimination tas...

  4. 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.

  5. 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.

  6. A Quantum Multi-Proxy Weak Blind Signature Scheme Based on Entanglement Swapping

    Science.gov (United States)

    Yan, LiLi; Chang, Yan; Zhang, ShiBin; Han, GuiHua; Sheng, ZhiWei

    2016-11-01

    In this paper, we present a multi-proxy weak blind signature scheme based on quantum entanglement swapping of Bell states. In the scheme, proxy signers can finish the signature instead of original singer with his/her authority. It can be applied to the electronic voting system, electronic paying system, etc. The scheme uses the physical characteristics of quantum mechanics to implement delegation, signature and verification. It could guarantee not only the unconditionally security but also the anonymity of the message owner. The security analysis shows the scheme satisfies the security features of multi-proxy weak signature, singers cannot disavowal his/her signature while the signature cannot be forged by others, and the message owner can be traced.

  7. Educational Applications for Blind and Partially Sighted Pupils Based on Speech Technologies for Serbian.

    Science.gov (United States)

    Lučić, Branko; Ostrogonac, Stevan; Vujnović Sedlar, Nataša; Sečujski, Milan

    2015-01-01

    The inclusion of persons with disabilities has always represented an important issue. Advancements within the field of computer science have enabled the development of different types of aids, which have significantly improved the quality of life of the disabled. However, for some disabilities, such as visual impairment, the purpose of these aids is to establish an alternative communication channel and thus overcome the user's disability. Speech technologies play the crucial role in this process. This paper presents the ongoing efforts to create a set of educational applications based on speech technologies for Serbian for the early stages of education of blind and partially sighted children. Two educational applications dealing with memory exercises and comprehension of geometrical shapes are presented, along with the initial tests results obtained from research including visually impaired pupils.

  8. Blind image watermarking technique based on differential embedding in DWT and DCT domains

    Science.gov (United States)

    Benoraira, Ali; Benmahammed, Khier; Boucenna, Noureddine

    2015-12-01

    This paper presents a new blind and robust image watermarking scheme based on discrete wavelet transform (DWT) and discrete cosine transform (DCT). Two DCT-transformed sub-vectors are used to embed the bits of the watermark sequence in a differential manner. The original sub-vectors are obtained by the sub-sampling of the approximation coefficients of the DWT transform of the host image. During the extraction stage, the simple difference between the corresponding sub-vectors of the watermarked image, gives directly the embedded watermark sequence. Experimental results demonstrate that the proposed technique successfully fulfills the requirement of imperceptibility and provides high robustness against a number of image-processing attacks, such as JPEG compression, noise adding, low-pass filtering, sharpening, and bit-plane removal. Our scheme exhibits also an acceptable to good performance against some geometrical attacks such as resizing and cropping.

  9. Blind multiuser detector for chaos-based CDMA using support vector machine.

    Science.gov (United States)

    Kao, Johnny Wei-Hsun; Berber, Stevan Mirko; Kecman, Vojislav

    2010-08-01

    The algorithm and the results of a blind multiuser detector using a machine learning technique called support vector machine (SVM) on a chaos-based code division multiple access system is presented in this paper. Simulation results showed that the performance achieved by using SVM is comparable to existing minimum mean square error (MMSE) detector under both additive white Gaussian noise (AWGN) and Rayleigh fading conditions. However, unlike the MMSE detector, the SVM detector does not require the knowledge of spreading codes of other users in the system or the estimate of the channel noise variance. The optimization of this algorithm is considered in this paper and its complexity is compared with the MMSE detector. This detector is much more suitable to work in the forward link than MMSE. In addition, original theoretical bit-error rate expressions for the SVM detector under both AWGN and Rayleigh fading are derived to verify the simulation results.

  10. Gene Expression-Based Survival Prediction in Lung Adenocarcinoma: A Multi-Site, Blinded Validation Study

    Science.gov (United States)

    Shedden, Kerby; Taylor, Jeremy M.G.; Enkemann, Steve A.; Tsao, Ming S.; Yeatman, Timothy J.; Gerald, William L.; Eschrich, Steve; Jurisica, Igor; Venkatraman, Seshan E.; Meyerson, Matthew; Kuick, Rork; Dobbin, Kevin K.; Lively, Tracy; Jacobson, James W.; Beer, David G.; Giordano, Thomas J.; Misek, David E.; Chang, Andrew C.; Zhu, Chang Qi; Strumpf, Dan; Hanash, Samir; Shepherd, Francis A.; Ding, Kuyue; Seymour, Lesley; Naoki, Katsuhiko; Pennell, Nathan; Weir, Barbara; Verhaak, Roel; Ladd-Acosta, Christine; Golub, Todd; Gruidl, Mike; Szoke, Janos; Zakowski, Maureen; Rusch, Valerie; Kris, Mark; Viale, Agnes; Motoi, Noriko; Travis, William; Sharma, Anupama

    2009-01-01

    Although prognostic gene expression signatures for survival in early stage lung cancer have been proposed, for clinical application it is critical to establish their performance across different subject populations and in different laboratories. Here we report a large, training-testing, multi-site blinded validation study to characterize the performance of several prognostic models based on gene expression for 442 lung adenocarcinomas. The hypotheses proposed examined whether microarray measurements of gene expression either alone or combined with basic clinical covariates (stage, age, sex) can be used to predict overall survival in lung cancer subjects. Several models examined produced risk scores that substantially correlated with actual subject outcome. Most methods performed better with clinical data, supporting the combined use of clinical and molecular information when building prognostic models for early stage lung cancer. This study also provides the largest available set of microarray data with extensive pathological and clinical annotation for lung adenocarcinomas. PMID:18641660

  11. Information Seeking Behavior in Blind People of Iran : a Survey based on Various Experiences faced by them

    Directory of Open Access Journals (Sweden)

    Hasan Siamian

    2016-12-01

    Full Text Available Access to information and its dissemination for the planning of health and social care is essential. While information is not always available as per the needs of the blind people, thus the public libraries and information centers led for meeting the information needs culture and proper knowledge. The study was based on a Descriptive-analytic method in which we included 384 blind people of both the sex selected by the multi-clustering method from 10 provinces of Iran. Health information of the subjects was collect through a researcher-based questionnaire. Results showed that religion, occupations, and access to healthy living, were the first top priority of blind people for meeting information needs in three cultural; social in addition, health forms. The blind people try to look for information on a daily basis and seeking up-to-date technologies. They are most used to audio media rather than any other media to access, utilise information, and rarely used new technologies. Unlike normal people, blind people have high expectations from the library. An attempt has also been taken to present a new model.

  12. Comparison between Conventional Blind Embryo Transfer and Embryo Transfer Based on Previously Measured Uterine Length

    Directory of Open Access Journals (Sweden)

    Nasrin Saharkhiz

    2014-11-01

    Full Text Available Background: Embryo transfer (ET is one of the most important steps in assisted reproductive technology (ART cycles and affected by many factors namely the depth of embryo deposition in uterus. In this study, the outcomes of intracytoplasmic sperm injection (ICSI cycles after blind embryo transfer and embryo transfer based on previously measured uterine length using vaginal ultrasound were compared. Materials and Methods: This prospective randomised clinical trial included one hundred and forty non-donor fresh embryo transfers during January 2010 to June 2011. In group I, ET was performed using conventional (blind method at 5-6cm from the external os, and in group II, ET was done at a depth of 1-1.5 cm from the uterine fundus based on previously measured uterine length using vaginal sonography. Appropriate statistical analysis was performed using Student’s t test and Chi-square or Fisher’s exact test. The software that we used was PASW statistics version 18. A p value <0.05 was considered statistically significant. Results: Chemical pregnancy rate was 28.7% in group I and 42.1% in group II, while the difference was not statistically significant (p=0.105. Clinical pregnancy, ongoing pregnancy and implantation rates for group I were 21.2%, 17.7%, and 12.8%, while for group II were 33.9%, 33.9%, and 22.1, respectively. In group I and group II, abortion rates were 34.7% and 0%, respectively, indicating a statistically significant difference (p<0.005. No ectopic pregnancy occurred in two groups. Conclusion: The use of uterine length measurement during treatment cycle in order to place embryos at depth of 1-1.5cm from fundus significantly increases clinical and ongoing pregnancy and implantation rates, while leads to a decrease in abortion rate (Registration Number: IRCT2014032512494N1.

  13. Blinded double reading yields a higher programme sensitivity than non-blinded double reading at digital screening mammography: a prospected population based study in the south of The Netherlands.

    Science.gov (United States)

    Klompenhouwer, Elisabeth G; Voogd, Adri C; den Heeten, Gerard J; Strobbe, Luc J A; de Haan, Anton F J; Wauters, Carla A; Broeders, Mireille J M; Duijm, Lucien E M

    2015-02-01

    To prospectively determine the screening mammography outcome at blinded and non-blinded double reading in a biennial population based screening programme in the south of the Netherlands. We included a consecutive series of 87,487 digital screening mammograms, obtained between July 2009 and July 2011. Screening mammograms were double read in either a blinded (2nd reader was not informed about the 1st reader's decision) or non-blinded fashion (2nd reader was informed about the 1st reader's decision). This reading strategy was alternated on a monthly basis. Women with discrepant readings between the two radiologists were always referred for further analysis. During 2 years follow-up, we collected the radiology reports, surgical correspondence and pathology reports of all referred women and interval breast cancers. Respectively 44,491 and 42,996 screens had been read either in a blinded or non-blinded fashion. Referral rate (3.3% versus 2.8%, preading whereas the cancer detection rate per 1000 screens (7.4 versus 6.5, p=0.14) and positive predictive value of referral (22% versus 23%, p=0.51) were comparable. Blinded double reading resulted in a significantly higher programme sensitivity (83% versus 76%, p=0.01). Per 1000 screened women, blinded double reading would yield 0.9 more screen detected cancers and 0.6 less interval cancers than non-blinded double reading, at the expense of 4.4 more recalls. We advocate the use of blinded double reading in order to achieve a better programme sensitivity, at the expense of an increased referral rate and false positive referral rate. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Blind Quantum Signature with Blind Quantum Computation

    Science.gov (United States)

    Li, Wei; Shi, Ronghua; Guo, Ying

    2017-04-01

    Blind quantum computation allows a client without quantum abilities to interact with a quantum server to perform a unconditional secure computing protocol, while protecting client's privacy. Motivated by confidentiality of blind quantum computation, a blind quantum signature scheme is designed with laconic structure. Different from the traditional signature schemes, the signing and verifying operations are performed through measurement-based quantum computation. Inputs of blind quantum computation are securely controlled with multi-qubit entangled states. The unique signature of the transmitted message is generated by the signer without leaking information in imperfect channels. Whereas, the receiver can verify the validity of the signature using the quantum matching algorithm. The security is guaranteed by entanglement of quantum system for blind quantum computation. It provides a potential practical application for e-commerce in the cloud computing and first-generation quantum computation.

  15. Blind Quantum Signature with Blind Quantum Computation

    Science.gov (United States)

    Li, Wei; Shi, Ronghua; Guo, Ying

    2016-12-01

    Blind quantum computation allows a client without quantum abilities to interact with a quantum server to perform a unconditional secure computing protocol, while protecting client's privacy. Motivated by confidentiality of blind quantum computation, a blind quantum signature scheme is designed with laconic structure. Different from the traditional signature schemes, the signing and verifying operations are performed through measurement-based quantum computation. Inputs of blind quantum computation are securely controlled with multi-qubit entangled states. The unique signature of the transmitted message is generated by the signer without leaking information in imperfect channels. Whereas, the receiver can verify the validity of the signature using the quantum matching algorithm. The security is guaranteed by entanglement of quantum system for blind quantum computation. It provides a potential practical application for e-commerce in the cloud computing and first-generation quantum computation.

  16. Blind range influence on guidance loop performance: An adjoint-based analysis

    NARCIS (Netherlands)

    Bucco, D.; Weiss, M.

    2013-01-01

    In this paper, we investigate the use of adjoint simulation for assessing the miss distance performance of a generic guidance system under the influence of a blind range condition. The term "blind range" refers to that final portion of the missile trajectory for which sensor data are not available.

  17. Efficient blind decoders for additive spread spectrum embedding based data hiding

    Science.gov (United States)

    Valizadeh, Amir; Wang, Z. Jane

    2012-12-01

    This article investigates efficient blind watermark decoding approaches for hidden messages embedded into host images, within the framework of additive spread spectrum (SS) embedding based for data hiding. We study SS embedding in both the discrete cosine transform and the discrete Fourier transform (DFT) domains. The contributions of this article are multiple-fold: first, we show that the conventional SS scheme could not be applied directly into the magnitudes of the DFT, and thus we present a modified SS scheme and the optimal maximum likelihood (ML) decoder based on the Weibull distribution is derived. Secondly, we investigate the improved spread spectrum (ISS) embedding, an improved technique of the traditional additive SS, and propose the modified ISS scheme for information hiding in the magnitudes of the DFT coefficients and the optimal ML decoders for ISS embedding are derived. We also provide thorough theoretical error probability analysis for the aforementioned decoders. Thirdly, sub-optimal decoders, including local optimum decoder (LOD), generalized maximum likelihood (GML) decoder, and linear minimum mean square error (LMMSE) decoder, are investigated to reduce the required prior information at the receiver side, and their theoretical decoding performances are derived. Based on decoding performances and the required prior information for decoding, we discuss the preferred host domain and the preferred decoder for additive SS-based data hiding under different situations. Extensive simulations are conducted to illustrate the decoding performances of the presented decoders.

  18. A Charrelation Matrix-Based Blind Adaptive Detector for DS-CDMA Systems.

    Science.gov (United States)

    Luo, Zhongqiang; Zhu, Lidong

    2015-08-14

    In this paper, a blind adaptive detector is proposed for blind separation of user signals and blind estimation of spreading sequences in DS-CDMA systems. The blind separation scheme exploits a charrelation matrix for simple computation and effective extraction of information from observation signal samples. The system model of DS-CDMA signals is modeled as a blind separation framework. The unknown user information and spreading sequence of DS-CDMA systems can be estimated only from the sampled observation signals. Theoretical analysis and simulation results show that the improved performance of the proposed algorithm in comparison with the existing conventional algorithms used in DS-CDMA systems. Especially, the proposed scheme is suitable for when the number of observation samples is less and the signal to noise ratio (SNR) is low.

  19. Non-blind Data hiding for RGB images using DCT-based fusion and H.264 compression concepts

    Directory of Open Access Journals (Sweden)

    Safwat Hamad

    Full Text Available Steganography is the field of research that provides innovative solutions to the problem of secure data communication. In this paper, a non-blind data hiding technique is proposed which is based on data fusion between both the cover and the secret images. ...

  20. Estimating Digital Inter-Symbol Interference Channel Blindly Based on the One-Step Branch Transition Rules in Trellises

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A novel discrete-time digital inter-symbol interference (ISI) channel blind estimation sub-optimal algorithm is proposed. This algorithm reduces the complexity of the optimal maximum likelihood sequence estimation(MLSE) considerably based on the one-step branch transition rules in trellises, and is suitable for the estimation of the channels with small lengths of ISI.

  1. Mouth-clicks used by blind expert human echolocators - signal description and model based signal synthesis.

    Directory of Open Access Journals (Sweden)

    Lore Thaler

    2017-08-01

    Full Text Available Echolocation is the ability to use sound-echoes to infer spatial information about the environment. Some blind people have developed extraordinary proficiency in echolocation using mouth-clicks. The first step of human biosonar is the transmission (mouth click and subsequent reception of the resultant sound through the ear. Existing head-related transfer function (HRTF data bases provide descriptions of reception of the resultant sound. For the current report, we collected a large database of click emissions with three blind people expertly trained in echolocation, which allowed us to perform unprecedented analyses. Specifically, the current report provides the first ever description of the spatial distribution (i.e. beam pattern of human expert echolocation transmissions, as well as spectro-temporal descriptions at a level of detail not available before. Our data show that transmission levels are fairly constant within a 60° cone emanating from the mouth, but levels drop gradually at further angles, more than for speech. In terms of spectro-temporal features, our data show that emissions are consistently very brief (~3ms duration with peak frequencies 2-4kHz, but with energy also at 10kHz. This differs from previous reports of durations 3-15ms and peak frequencies 2-8kHz, which were based on less detailed measurements. Based on our measurements we propose to model transmissions as sum of monotones modulated by a decaying exponential, with angular attenuation by a modified cardioid. We provide model parameters for each echolocator. These results are a step towards developing computational models of human biosonar. For example, in bats, spatial and spectro-temporal features of emissions have been used to derive and test model based hypotheses about behaviour. The data we present here suggest similar research opportunities within the context of human echolocation. Relatedly, the data are a basis to develop synthetic models of human echolocation

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

    Institute of Scientific and Technical Information of China (English)

    Qiang Li; Sheng Liao; Honggang Wei; Mangzuo Shen

    2007-01-01

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

  3. 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...... blindness focusing on the development of either a new moral vision of our obligations or new visions of what a good life is....

  4. 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-

  5. Blind Decorrelating Detection Based on Particle Swarm Optimization under Spreading Code Mismatch

    Institute of Scientific and Technical Information of China (English)

    Jhih-Chung Chang; Chih-Chang Shen

    2014-01-01

    A way of resolving spreading code mismatches in blind multiuser detection with a particle swarm optimization (PSO) approach is proposed. It has been shown that the PSO algorithm incorporating the linear system of the decorrelating detector, which is termed as decorrelating PSO (DPSO), can significantly improve the bit error rate (BER) and the system capacity. As the code mismatch occurs, the output BER performance is vulnerable to degradation for DPSO. With a blind decorrelating scheme, the proposed blind DPSO (BDPSO) offers more robust capabilities over existing DPSO under code mismatch scenarios.

  6. Access to Mathematics by Blind Students: A Global Problem

    OpenAIRE

    Karshmer, Arthur I.; 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...

  7. 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.

  8. A Robust Blind Quantum Copyright Protection Method for Colored Images Based on Owner's Signature

    Science.gov (United States)

    Heidari, Shahrokh; Gheibi, Reza; Houshmand, Monireh; Nagata, Koji

    2017-08-01

    Watermarking is the imperceptible embedding of watermark bits into multimedia data in order to use for different applications. Among all its applications, copyright protection is the most prominent usage which conceals information about the owner in the carrier, so as to prohibit others from assertion copyright. This application requires high level of robustness. In this paper, a new blind quantum copyright protection method based on owners's signature in RGB images is proposed. The method utilizes one of the RGB channels as indicator and two remained channels are used for embedding information about the owner. In our contribution the owner's signature is considered as a text. Therefore, in order to embed in colored image as watermark, a new quantum representation of text based on ASCII character set is offered. Experimental results which are analyzed in MATLAB environment, exhibit that the presented scheme shows good performance against attacks and can be used to find out who the real owner is. Finally, the discussed quantum copyright protection method is compared with a related work that our analysis confirm that the presented scheme is more secure and applicable than the previous ones currently found in the literature.

  9. An information theory criteria based blind method for enumerating active users in DS-CDMA system

    Science.gov (United States)

    Samsami Khodadad, Farid; Abed Hodtani, Ghosheh

    2014-11-01

    In this paper, a new and blind algorithm for active user enumeration in asynchronous direct sequence code division multiple access (DS-CDMA) in multipath channel scenario is proposed. The proposed method is based on information theory criteria. There are two main categories of information criteria which are widely used in active user enumeration, Akaike Information Criterion (AIC) and Minimum Description Length (MDL) information theory criteria. The main difference between these two criteria is their penalty functions. Due to this difference, MDL is a consistent enumerator which has better performance in higher signal-to-noise ratios (SNR) but AIC is preferred in lower SNRs. In sequel, we propose a SNR compliance method based on subspace and training genetic algorithm to have the performance of both of them. Moreover, our method uses only a single antenna, in difference to the previous methods which decrease hardware complexity. Simulation results show that the proposed method is capable of estimating the number of active users without any prior knowledge and the efficiency of the method.

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

    Institute of Scientific and Technical Information of China (English)

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

    2009-01-01

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

  11. New blind mobility aid devices based on the ultrasonic Doppler effect.

    Science.gov (United States)

    Bitjoka, L; Pourcelot, L

    1999-09-01

    An original approach to electronic blind mobility aid combined with ultrasonic wave processing and spatial hearing has allowed the design of new blind mobility aid devices. These devices convert inaudible ultrasound echoes into audible sound via the Doppler effect, preserving even slight modification of the high frequency wave, so as to provide the user with higher acuity information regarding his movement, as well as object movement and their spatial location.

  12. PERCEPT-II: smartphone based indoor navigation system for the blind.

    Science.gov (United States)

    Ganz, Aura; Schafer, James M; Tao, Yang; Wilson, Carole; Robertson, Meg

    2014-01-01

    In this paper we introduce PERCEPT-II, a low cost and user friendly indoor navigation system for blind and visually impaired users. Using an Android Smartphone that runs PERCEPT-II application with accessibility features, the blind user obtains navigation instructions to the chosen destination when touching specific landmarks tagged with Near Field Communication tags. The system was deployed and tested in a large building at the University of Massachusetts at Amherst.

  13. Change-readiness of the blind: A hospital based study in a coastal town of South India

    Directory of Open Access Journals (Sweden)

    Ramya Shetty

    2014-01-01

    Conclusion: The results suggest that there is a need to modify health policy to include blind rehabilitation, to improve visibility of blind rehabilitation centers, to include family members and co-professionals while managing the blind so that we treat the "blind person" and not a "pair of blind eyes."

  14. Blind 3D Model Watermarking Based on Multi-Resolution Representation and Fuzzy Logic

    CERN Document Server

    Tamane, Sharvari C

    2012-01-01

    Insertion of a text message, audio data or/and an image into another image or 3D model is called as a watermarking process. Watermarking has variety of applications like: Copyright Protection, Owner Identification, Copy Protection and Data Hiding etc., depending upon the type of watermark insertion algorithm. Watermark remains in the content after applying various attacks without any distortions. The blind watermarking method used in the system is based on a wavelet transform, a fuzzy inference system and a multi-resolution representation (MRR) of the 3d model. The watermark scrambled by Arnold Transform is embedded in the wavelet coefficients at third resolution level of the MRR. Fuzzy logic approach used in the method makes it to approximate the best possible gain with an accurate scaling factor so that the watermark remains invisible. The fuzzy input variables are computed for each wavelet coefficient in the 3D model. The output of the fuzzy system is a single value which is a perceptual value for each cor...

  15. Trellis-Based Iterative Adaptive Blind Sequence Estimation for Uncoded/Coded Systems with Differential Precoding

    Directory of Open Access Journals (Sweden)

    Chen Xiao-Ming

    2005-01-01

    Full Text Available We propose iterative, adaptive trellis-based blind sequence estimators, which can be interpreted as reduced-complexity receivers derived from the joint ML data/channel estimation problem. The number of states in the trellis is considered as a design parameter, providing a trade-off between performance and complexity. For symmetrical signal constellations, differential encoding or generalizations thereof are necessary to combat the phase ambiguity. At the receiver, the structure of the super-trellis (representing differential encoding and intersymbol interference is explicitly exploited rather than doing differential decoding just for resolving the problem of phase ambiguity. In uncoded systems, it is shown that the data sequence can only be determined up to an unknown shift index. This shift ambiguity can be resolved by taking an outer channel encoder into account. The average magnitude of the soft outputs from the corresponding channel decoder is exploited to identify the shift index. For frequency-hopping systems over fading channels, a double serially concatenated scheme is proposed, where the inner code is applied to combat the shift ambiguity and the outer code provides time diversity in conjunction with an interburst interleaver.

  16. A Novel Semi-blind Watermarking Algorithm Based on Fractal Dimension and Image Feature

    Institute of Scientific and Technical Information of China (English)

    NIRongrong; RUANQiuqi

    2004-01-01

    This paper presents a novel semi-blind watermarking algorithm based on fractal dimension and image feature. An original image is divided into blocks with fixed size. According to the idea of the second generation watermarking[1], the image is analyzed using fractal dimension to attain its feature blocks containing edges and textures that are used in the later embedding process and used to form a feature label. The watermark that is the fusion of the feature label and a binary copyright symbol not only represents the copyright symbol, but also reflects the feature of the image. Arnold iteration transform is employed to increase the security of watermark. Then,DCT (Discrete cosine transform) is applied to the feature blocks. The secure watermark that is adaptive to the individual image is embedded into the relations between middle-frequency coefficients and corresponding DC coefficients. The detection and extraction procedure is a semiblind one which does not use the original image but the watermark. Only those who have the original watermarkand the key can detect and extract the right watermark.This makes the approach authentic and have high securitylevel. Experimental results show that this algorithm can get good perceptual invisibility, adaptability and security.And it is robust against cropping, scribbling, low or highpass filtering, adding noise and JPEG compression.

  17. Blind Synchronization in Asynchronous UWB Networks Based on the Transmit-Reference Scheme

    Directory of Open Access Journals (Sweden)

    Leus Geert

    2006-01-01

    Full Text Available Ultra-wideband (UWB wireless communication systems are based on the transmission of extremely narrow pulses, with a duration inferior to a nanosecond. The application of transmit reference (TR to UWB systems allows to side-step channel estimation at the receiver, with a tradeoff of the effective transmission bandwidth, which is reduced by the usage of a reference pulse. Similar to CDMA systems, different users can share the same available bandwidth by means of different spreading codes. This allows the receiver to separate users, and to recover the timing information of the transmitted data packets. The nature of UWB transmissions—short, burst-like packets—requires a fast synchronization algorithm, that can accommodate several asynchronous users. Exploiting the fact that a shift in time corresponds to a phase rotation in the frequency domain, a blind and computationally effcient synchronization algorithm that takes advantage of the shift invariance structure in the frequency domain is proposed in this paper. Integer and fractional delay estimations are considered, along with a subsequent symbol estimation step. This results in a collision-avoiding multiuser algorithm, readily applicable to a fast acquisition procedure in a UWB ad hoc network.

  18. [Cortical blindness].

    Science.gov (United States)

    Chokron, S

    2014-02-01

    Cortical blindness refers to a visual loss induced by a bilateral occipital lesion. The very strong cooperation between psychophysics, cognitive psychology, neurophysiology and neuropsychology these latter twenty years as well as recent progress in cerebral imagery have led to a better understanding of neurovisual deficits, such as cortical blindness. It thus becomes possible now to propose an earlier diagnosis of cortical blindness as well as new perspectives for rehabilitation in children as well as in adults. On the other hand, studying complex neurovisual deficits, such as cortical blindness is a way to infer normal functioning of the visual system.

  19. Contrast properties of entropic criteria for blind source separation : a unifying framework based on information-theoretic inequalities/

    OpenAIRE

    Vrins, Frédéric

    2007-01-01

    In the recent years, Independent Component Analysis (ICA) has become a fundamental tool in adaptive signal and data processing, especially in the field of Blind Source Separation (BSS). Even though there exist some methods for which an algebraic solution to the ICA problem may be found, other iterative methods are very popular. Among them is the class of information-theoretic approaches, laying on entropies. The associated objective functions are maximized based on optimization schemes, and o...

  20. PROPAGATOR BASED CLOSED-FORM BLIND CARRIER FREQUENCY OFFSET ESTIMATION FOR OFDM SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    Li Jun; Liao Guisheng; Wu Yuntao

    2006-01-01

    Most of the blind Orthogonal Frequency Division Multiplexing (OFDM) Carrier Frequency Offeet (CFO) estimators necessitate large number of samples to ensure the estimation accuracy. However, the number of samples can not be selected too large because of the carrier offset drift. In this letter, a new closed form algorithm for blind OFDM CFO estimation in frequency-selective channel is proposed. This method utilizes the propagator obtained from data matrix and the diagonal loading technique, thus it has better performance even only using one or two OFDM blocks. Furthermore, the range of the CFO estimation which can be handled is overall transmission spectral. Simulation results confirm its effectiveness.

  1. Blind source separation for groundwater pressure analysis based on nonnegative matrix factorization

    Science.gov (United States)

    Alexandrov, Boian S.; Vesselinov, Velimir V.

    2014-09-01

    The identification of the physical sources causing spatial and temporal fluctuations of aquifer water levels is a challenging, yet a very important hydrogeological task. The fluctuations can be caused by variations in natural and anthropogenic sources such as pumping, recharge, barometric pressures, etc. The source identification can be crucial for conceptualization of the hydrogeological conditions and characterization of aquifer properties. We propose a new computational framework for model-free inverse analysis of pressure transients based on Nonnegative 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 subsurface flow medium. Our analysis only requires information about pressure 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 this new analysis on a data set from the Los Alamos National Laboratory site. We demonstrate that the sources identified by NMFk have real physical origins: barometric pressure and water-supply pumping effects. We also estimate the barometric pressure efficiency of the monitoring wells. The possible applications of the NMFk algorithm are not limited to hydrogeology problems; NMFk can be applied to any problem where temporal system behavior is observed at multiple locations and an unknown number of physical sources are causing these fluctuations.

  2. Postural control in blind subjects

    Directory of Open Access Journals (Sweden)

    Antonio Vinicius Soares

    2011-12-01

    Full Text Available Objective: To analyze postural control in acquired and congenitally blind adults. Methods: A total of 40 visually impaired adults participated in the research, divided into 2 groups, 20 with acquired blindness and 20 with congenital blindness - 21 males and 19 females, mean age 35.8 ± 10.8. The Brazilian version of Berg Balance Scale and the motor domain of functional independence measure were utilized. Results: On Berg Balance Scale the mean for acquired blindness was 54.0 ± 2.4 and 54.4 ± 2.5 for congenitally blind subjects; on functional independence measure the mean for acquired blind group was 87.1 ± 4.8 and 87.3 ± 2.3 for congenitally blind group. Conclusion: Based upon the scale used the results suggest the ability to control posture can be developed by compensatory mechanisms and it is not affected by visual loss in congenitally and acquired blindness.

  3. Wavelet-Based Blind Superresolution from Video Sequence and in MRI

    Science.gov (United States)

    2005-12-31

    algorithms,” IEEE Transactions on Image Processing, vol. 8, no. 2, 1999. [5] S. U. Pillai and B. Liang, “Blind image deconvolution using a robust GCD...with second genera- tion wavelets,” Signal Processing: Image Communication, vol. 19, no. 5, pp. 387–391, 2004. [11] C. A. Berenstein and E. V. Patrick

  4. On-line blind source separation algorithm based on second order statistics

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    An on-line blind source separation (BSS) algorithm is presented in this paper under the assumption that sources are temporarily correlated signals. By using only some of the observed samples in a recursive calculation, the whitening matrix and the rotation matrix could be approximately obtained through the measurement of only one cost function. Simulations show good performance of the algorithm.

  5. Design, Modeling and Implementation of Pic Based Wireless Control System to Eliminate Blind Spots in Vehicle Side Mirrors

    Directory of Open Access Journals (Sweden)

    Mahmoud Z. Iskandarani

    2008-01-01

    Full Text Available A PIC controlled IR system for the control of vehicle side mirror system movements for the purpose of revealing blind spots is designed and implemented. The designed and built system allows the side view mirrors to be adjusted based on the driver head movement. The infrared-based head tracking system maps a predetermined coordinates for head movements and results in a triangularly computable geometry, which is fed to the PIC, based controlling system. This will cause the vehicle mirror movement via carefully selected miniature motors.

  6. Kurtosis based blind source extraction of complex noncircular signals with application in EEG artifact removal in real-time

    Directory of Open Access Journals (Sweden)

    Soroush eJavidi

    2011-10-01

    Full Text Available A new class of complex domain blind source extraction (BSE algorithms suitable for the extraction of both circular and noncircular complex signals is proposed. This is achieved through sequential extraction based on the degree of kurtosis and in the presence of noncircular measurement noise. The existence and uniqueness analysis of the solution is followed by a study of fast converging variants of the algorithm. The performance is first assessed through simulations on well understood benchmark signals, followed by a case study on real-time artifact removal from EEG signals, verified using both qualitative and quantitative metrics. The results illustrate the power of the proposed approach in real-time blind extraction of general complex-valued sources.

  7. On the Performance of SVD-DWT Based Digital Video Watermarking Technique with Semi-Blind Detector

    Directory of Open Access Journals (Sweden)

    Tarzan Basaruddin

    2010-10-01

    Full Text Available This paper presents a watermarking technique for digital video. The proposed scheme is developed based on the work of Ganic and Chan which took the virtue of SVD and DWT. While the previous works of Chan has the blind detector property, our attempt is to develop a scheme with semi-blind detector, by using the merit of the DWT-SDV technique proposed by Ganic which was originally applied to still image. Overall, our experimental results show that our proposed scheme has a very good imperceptibility and is reasonably robust especially under several attacks such as compression, blurring, cropping, and sharpening.

  8. Research on the flooding routing arithmetic of wireless sensor networks based on solar-blind UV light

    Institute of Scientific and Technical Information of China (English)

    ZHAO Tai-fei; KE Xi-zheng; DENG Li-jun; HE Hua

    2010-01-01

    @@ In this paper the solar-blind ultraviolet(UV)light is used as communication medium for wireless sensor networks(WSNs).Three types of single scattering UV communication models are introduced and a directional flooding model is proposed,which are based on the directionality of the UV communication and the traditional flooding routing model.The delay,delay jitter,throughput and energy consumption of the three types of communications of the new model are simulated and compared.The results indicate that the proposed directional flooding model can effectively avoid the unidirectionality and the blindness of the traditional flooding broadcast messages.The energy consumption of nodes in the network is reduced and the life cycle of the network is extended.

  9. Prediction of blind frequency in lock-in thermography using electro-thermal model based numerical simulation

    Science.gov (United States)

    Chatterjee, Krishnendu; Tuli, Suneet

    2013-11-01

    Lock-in thermography is increasingly becoming popular as a non-destructive testing technique for defect detection in composite materials for its low heating excitation. The experimental data is processed with Fourier transformation to produce phase and amplitude images. Phase images, though immune to surface emissivity variation, suffer from blind frequency effect, where a defect becomes invisible at a certain excitation frequency. There exists no analytical model to predict this 3-dimensional heat flow phenomenon. This paper presents a study of blind frequency using electro-thermal model based numerical simulation on a piece of thermally anisotropic carbon fibre composite. The performance of the simulator is optimized for spatial mesh size. Further the effect of paint layer, which is often applied to the sample surface for better thermal imaging, has been incorporated in the simulation. Finally, both experimental and simulation results are presented side-by-side for easy comparison.

  10. Development of an audio-based virtual gaming environment to assist with navigation skills in the blind.

    Science.gov (United States)

    Connors, Erin C; Yazzolino, Lindsay A; Sánchez, Jaime; Merabet, Lotfi B

    2013-03-27

    Audio-based Environment Simulator (AbES) is virtual environment software designed to improve real world navigation skills in the blind. Using only audio based cues and set within the context of a video game metaphor, users gather relevant spatial information regarding a building's layout. This allows the user to develop an accurate spatial cognitive map of a large-scale three-dimensional space that can be manipulated for the purposes of a real indoor navigation task. After game play, participants are then assessed on their ability to navigate within the target physical building represented in the game. Preliminary results suggest that early blind users were able to acquire relevant information regarding the spatial layout of a previously unfamiliar building as indexed by their performance on a series of navigation tasks. These tasks included path finding through the virtual and physical building, as well as a series of drop off tasks. We find that the immersive and highly interactive nature of the AbES software appears to greatly engage the blind user to actively explore the virtual environment. Applications of this approach may extend to larger populations of visually impaired individuals.

  11. Blind Source Separation Model of Earth-Rock Junctions in Dike Engineering Based on Distributed Optical Fiber Sensing Technology

    Directory of Open Access Journals (Sweden)

    Huaizhi Su

    2015-01-01

    Full Text Available Distributed temperature sensing (DTS provides an important technology support for the earth-rock junctions of dike projects (ERJD, which are binding sites between culvert, gates, and pipes and dike body and dike foundation. In this study, a blind source separation model is used for the identification of leakages based on the temperature data of DTS in leakage monitoring of ERJD. First, a denoising method is established based on the temperature monitoring data of distributed optical fiber in ERJD by a wavelet packet signal decomposition technique. The temperature monitoring messages of fibers are combined response for leakages and other factors. Its character of unclear responding mechanism is very obvious. Thus, a blind source separation technology is finally selected. Then, the rule of temperature measurement data for optical fiber is analyzed and its temporal and spatial change process is also discussed. The realization method of the blind source separation model is explored by combining independent component analysis (ICA with principal component analysis (PCA. The practical test result in an example shows that the method could efficiently locate and identify the leakage location of ERJD. This paper is expected to be useful for further scientific research and efficient applications of distributed optical fiber sensing technology.

  12. 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....

  13. 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.

  14. Blind equalization and automatic modulation classification based on subspace for subcarrier MPSK optical communications

    Science.gov (United States)

    Chen, Dan; Guo, Lin-yuan; Wang, Chen-hao; Ke, Xi-zheng

    2017-07-01

    Equalization can compensate channel distortion caused by channel multipath effects, and effectively improve convergent of modulation constellation diagram in optical wireless system. In this paper, the subspace blind equalization algorithm is used to preprocess M-ary phase shift keying (MPSK) subcarrier modulation signal in receiver. Mountain clustering is adopted to get the clustering centers of MPSK modulation constellation diagram, and the modulation order is automatically identified through the k-nearest neighbor (KNN) classifier. The experiment has been done under four different weather conditions. Experimental results show that the convergent of constellation diagram is improved effectively after using the subspace blind equalization algorithm, which means that the accuracy of modulation recognition is increased. The correct recognition rate of 16PSK can be up to 85% in any kind of weather condition which is mentioned in paper. Meanwhile, the correct recognition rate is the highest in cloudy and the lowest in heavy rain condition.

  15. 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.

  16. Blindness and visual impairment in retinitis pigmentosa: a Cameroonian hospital-based study

    Directory of Open Access Journals (Sweden)

    André Omgbwa Eballe

    2010-06-01

    Full Text Available André Omgbwa Eballe1, Godefroy Koki2, Claude Bernard Emche2, Lucienne Assumpta Bella2, Jeanne Mayouego Kouam2, Justin Melong31Faculty of Medicine and Pharmaceutical Sciences, University of Douala; 2Faculty of Medicine and Biomedical Sciences, University of Yaoundé; 3Translation Unit, Ministry of Public Health, Yaoundé, CameroonAim: We performed a retrospective, analytical study in February 2010 on all retinitis pigmentosa cases seen during ophthalmologic consultation at the Gyneco-Obstetrics and Pediatric Hospital of Yaounde between March 2002 and December 2009 (82 months. The aim of this research was to determine the significance of blindness and visual impairment associated with retinitis pigmentosa in Cameroon.Results: Forty cases were reported, corresponding to a hospital prevalence of 1.6/1000 (21 men and 19 women. The average age of the patients was 43.3 ± 18 years, ranging between 6 and 74 years. Bilateral blindness and low vision was noted in 30% and 27.5% of patients, respectively. The average age of patients with low vision was 40.38 ± 16.27 years and the average age of those with bilateral blindness was 51.08 ± 15.79 years. Retinitis pigmentosa was bilateral in all cases and isolated (without any eye or general additional disease in 67.5% of cases.Conclusion: Visual impairment is common and becomes even more severe with aging. Patients should be screened to enable them to benefit from management focusing on both appropriate treatment and genetic counseling.Keywords: retinitis pigmentosa, Cameroon, blindness, Yaoundé

  17. Randomized double blind placebo control studies, the "Gold Standard" in intervention based studies

    Directory of Open Access Journals (Sweden)

    Shobha Misra

    2012-01-01

    Full Text Available Studies follow a hierarchy in terms of the quality of evidence that they can provide. Randomized double blind placebo control (RDBPC studies are considered the "gold standard" of epidemiologic studies. And the same is discussed at length in this paper taking example of a real journal article employing this study design to answer the research question; "Does once daily dose of Valacyclovir reduce the risk of transmission of genital herpes in a susceptible partner?" RDBPC studies remain the most convincing research design in which randomly assigning the intervention can eliminate the influence of unknown or immeasurable confounding variables that may otherwise lead to biased and incorrect estimate of treatment effect. Also, randomization eliminates confounding by baseline variables and blinding eliminates confounding by co-interventions, thus eliminating the possibility that the observed effects of intervention are due to differential use of other treatments. The best comparison is placebo control that allows participants, investigators and study staff to be blinded. The advantage of trial over an observational study is the ability to demonstrate causality. Hope, this will be useful to neophyte researchers to understand causal hierarchy when critically evaluating epidemiologic literature.

  18. Randomized double blind placebo control studies, the "Gold Standard" in intervention based studies.

    Science.gov (United States)

    Misra, Shobha

    2012-07-01

    Studies follow a hierarchy in terms of the quality of evidence that they can provide. Randomized double blind placebo control (RDBPC) studies are considered the "gold standard" of epidemiologic studies. And the same is discussed at length in this paper taking example of a real journal article employing this study design to answer the research question; "Does once daily dose of Valacyclovir reduce the risk of transmission of genital herpes in a susceptible partner?" RDBPC studies remain the most convincing research design in which randomly assigning the intervention can eliminate the influence of unknown or immeasurable confounding variables that may otherwise lead to biased and incorrect estimate of treatment effect. Also, randomization eliminates confounding by baseline variables and blinding eliminates confounding by co-interventions, thus eliminating the possibility that the observed effects of intervention are due to differential use of other treatments. The best comparison is placebo control that allows participants, investigators and study staff to be blinded. The advantage of trial over an observational study is the ability to demonstrate causality. Hope, this will be useful to neophyte researchers to understand causal hierarchy when critically evaluating epidemiologic literature.

  19. Performance of Entropy Based on Generalized Laplace Function For Blind Signal Separation

    Directory of Open Access Journals (Sweden)

    M.E. ABD El-AZIZ

    2011-01-01

    Full Text Available Blind signal separation is the problem of estimating a set of source signals from their mixture without prior knowledge about the source signals. Negentropy is an objective function used in the problem of BSS in which negentropy is an information theoretic quantity used as a measure of signal independence in the problem of blind signal separation and it is used as a quality criterion in various signal processing problems such as segmentation and detection. Negentropy is in some sense the optimal estimator of nongaussianity, as far as thestatistical performance is concerned. The problem in using negentropy is that it is computationally very difficult. Estimating negentropy using the definition would require an estimate of the probability density function. Therefore simpler approximations of negentropy are very useful but the performance of this approximation depend on choosing the probability density function so that we introduced in this paper a new non-quadratic function called Generalized Laplace Function . To estimate the parameters of such function we used twomethods first the maximum likelihood function and the second kurtosis. To blindly extract the independent source signals, we resort to FastICA approach. Simulation results show that the proposed approach is capable of separating mixture of signals and also show that the performance of generalized Laplace is best of all otherfunctions that had been proved its performance.

  20. Blind Masseurs

    Institute of Scientific and Technical Information of China (English)

    1997-01-01

    Guan Enming and his wife Hao Dejuan, a blind couple, vowed to "never become a burden for society." The couple retired from the QJngdao Massotherapy Hospital in 1992, and thereafter opened a private clinic with assistance from their

  1. Therapist guided internet based cognitive behavioural therapy for body dysmorphic disorder: single blind randomised controlled trial

    Science.gov (United States)

    Andersson, Erik; Mataix-Cols, David; Lichtenstein, Linn; Alström, Katarina; Andersson, Gerhard; Ljótsson, Brjánn; Rück, Christian

    2016-01-01

    Objectives To evaluate the efficacy of therapist guided internet based cognitive behavioural therapy (CBT) programme for body dysmorphic disorder (BDD-NET) compared with online supportive therapy. Design A 12 week single blind parallel group randomised controlled trial. Setting Academic medical centre. Participants 94 self referred adult outpatients with a diagnosis of body dysmorphic disorder and a modified Yale-Brown obsessive compulsive scale (BDD-YBOCS) score of ≥20. Concurrent psychotropic drug treatment was permitted if the dose had been stable for at least two months before enrolment and remained unchanged during the trial. Interventions Participants received either BDD-NET (n=47) or supportive therapy (n=47) delivered via the internet for 12 weeks. Main outcome measures The primary outcome was the BDD-YBOCS score after treatment and follow-up (three and six months from baseline) as evaluated by a masked assessor. Responder status was defined as a ≥30% reduction in symptoms on the scale. Secondary outcomes were measures of depression (MADRS-S), global functioning (GAF), clinical global improvement (CGI-I), and quality of life (EQ5D). The six month follow-up time and all outcomes other than BDD-YBOCS and MADRS-S at 3 months were not pre-specified in the registration at clinicaltrials.gov because of an administrative error but were included in the original trial protocol approved by the regional ethics committee before the start of the trial. Results BDD-NET was superior to supportive therapy and was associated with significant improvements in severity of symptoms of body dysmorphic disorder (BDD-YBOCS group difference −7.1 points, 95% confidence interval −9.8 to −4.4), depression (MADRS-S group difference −4.5 points, −7.5 to −1.4), and other secondary measures. At follow-up, 56% of those receiving BDD-NET were classed as responders, compared with 13% receiving supportive therapy. The number needed to treat was 2.34 (1.71 to 4.35). Self

  2. AlGaN-based material characterizations and recent development of related solar-blind ultraviolet detectors

    Science.gov (United States)

    Li, Xiangyang; Xu, Jintong; Zhang, Yan; Yuan, Yonggang; Chu, Kaihui; Li, Chao; Bao, Xichang; Wang, Ling

    2009-08-01

    Recently, AlGaN-based material and related devices have been investigated intensively because of their applications in ultraviolet solar-blind detectors, blue light-emitting diodes, UV laser diodes, and high-power-temperature devices. Due to intrinsic difficulty to grow high aluminum fraction material, achieving reasonable good quality of wafers is the key aspect to fabricate high performance solar-blind AlGaN-based detectors. Transmission spectra, XRD, and a two dimension transmission scanning system were employed to evaluate the properties of AlGaN-based material. Wet chemical etching process of n-type AlGaN in 20% aqueous KOH solutions was performed to reduce dry etching damages and the average leakage current. I-V characterization indicated that the average leakage current of the wet etching treated detectors was lower than that of the detectors without treatment by about one order of magnitude. Ti/Al/Ti/Au contact on n-type Al0.63Ga0.37N was optimized to get a low series resistance. 128×128 solar-blind AlGaN UV Focal Plane Arrays (FPAs) were fabricated and the performance were characterized. A CTIA (capacitive-transimpedance) readout circuit architecture has been proven to be well suited for AlGaN detectors arrays. The results show that 128×128 back-illuminated AlGaN PIN detector SNR is as high as 74 db at a speed of above 30 frames per second.

  3. 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.

  4. 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.

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

    Science.gov (United States)

    You, Rong-Yi; Chen, Zhong

    2005-11-01

    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.

  6. 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...

  7. Population-based survey of prevalence, causes, and risk factors for blindness and visual impairment in an aging Chinese metropolitan population.

    Science.gov (United States)

    Hu, Jian-Yan; Yan, Liang; Chen, Yong-Dong; Du, Xin-Hua; Li, Ting-Ting; Liu, De-An; Xu, Dong-Hong; Huang, Yi-Min; Wu, Qiang

    2017-01-01

    To assess the prevalence, causes, and risk factors for blindness and visual impairment among elderly (≥60 years of age) Chinese people in a metropolitan area of Shanghai, China. Random cluster sampling was conducted to identify participants among residents ≥60 years of age living in the Xietu Block, Xuhui District, Shanghai, China. Presenting visual acuity (PVA) and best-corrected visual acuity (BCVA) were checked by the Early Treatment Diabetic Retinopathy Study (ETDRS) visual chart. All eligible participants underwent a comprehensive eye examination. Blindness and visual impairment were defined according to World Health Organization (WHO) criteria. A total of 4190 persons (1688 men and 2502 women) participated in the study, and the response rate was 91.1%. Based on PVA, the prevalence of blindness was 1.1% and that of visual impairment was 7.6%. Based on BCVA, the prevalence of blindness and visual impairment decreased to 0.9% and 3.9%, respectively. Older (≥80 years of age) women, with low educational levels and smoking habits, exhibited a significantly greater chance for blindness and visual impairment than did those with high educational levels and no smoking habits (P<0.05). Based on PVA and BCVA, the main causes of blindness were cataract, myopic maculopathy, and age-related macular degeneration (AMD). Our findings help to identify the population in need of intervention, to highlight the need for additional eye healthcare services in urban China.

  8. A Context-Aware-Based Audio Guidance System for Blind People Using a Multimodal Profile Model

    Directory of Open Access Journals (Sweden)

    Qing Lin

    2014-10-01

    Full Text Available A wearable guidance system is designed to provide context-dependent guidance messages to blind people while they traverse local pathways. The system is composed of three parts: moving scene analysis, walking context estimation and audio message delivery. The combination of a downward-pointing laser scanner and a camera is used to solve the challenging problem of moving scene analysis. By integrating laser data profiles and image edge profiles, a multimodal profile model is constructed to estimate jointly the ground plane, object locations and object types, by using a Bayesian network. The outputs of the moving scene analysis are further employed to estimate the walking context, which is defined as a fuzzy safety level that is inferred through a fuzzy logic model. Depending on the estimated walking context, the audio messages that best suit the current context are delivered to the user in a flexible manner. The proposed system is tested under various local pathway scenes, and the results confirm its efficiency in assisting blind people to attain autonomous mobility.

  9. Information-Dispersion-Entropy-Based Blind Recognition of Binary BCH Codes in Soft Decision Situations

    Directory of Open Access Journals (Sweden)

    Yimeng Zhang

    2013-05-01

    Full Text Available A method of blind recognition of the coding parameters for binary Bose-Chaudhuri-Hocquenghem (BCH codes is proposed in this paper. We consider an intelligent communication receiver which can blindly recognize the coding parameters of the received data stream. The only knowledge is that the stream is encoded using binary BCH codes, while the coding parameters are unknown. The problem can be addressed on the context of the non-cooperative communications or adaptive coding and modulations (ACM for cognitive radio networks. The recognition processing includes two major procedures: code length estimation and generator polynomial reconstruction. A hard decision method has been proposed in a previous literature. In this paper we propose the recognition approach in soft decision situations with Binary-Phase-Shift-Key modulations and Additive-White-Gaussian-Noise (AWGN channels. The code length is estimated by maximizing the root information dispersion entropy function. And then we search for the code roots to reconstruct the primitive and generator polynomials. By utilizing the soft output of the channel, the recognition performance is improved and the simulations show the efficiency of the proposed algorithm.

  10. Visible-Blind UV Photodetector Based on Single-Walled Carbon Nanotube Thin Film/ZnO Vertical Heterostructures.

    Science.gov (United States)

    Li, Guanghui; Suja, Mohammad; Chen, Mingguang; Bekyarova, Elena; Haddon, Robert C; Liu, Jianlin; Itkis, Mikhail E

    2017-10-05

    Ultraviolet (UV) photodetectors based on heterojunctions of conventional (Ge, Si, and GaAs) and wide bandgap semiconductors have been recently demonstrated, but achieving high UV sensitivity and visible-blind photodetection still remains a challenge. Here, we utilized a semitransparent film of p-type semiconducting single-walled carbon nanotubes (SC-SWNTs) with an energy gap of 0.68 ± 0.07 eV in combination with a molecular beam epitaxy grown n-ZnO layer to build a vertical p-SC-SWNT/n-ZnO heterojunction-based UV photodetector. The resulting device shows a current rectification ratio of 10(3), a current photoresponsivity up to 400 A/W in the UV spectral range from 370 to 230 nm, and a low dark current. The detector is practically visible-blind with the UV-to-visible photoresponsivity ratio of 10(5) due to extremely short photocarrier lifetimes in the one-dimensional SWNTs because of strong electron-phonon interactions leading to exciton formation. In this vertical configuration, UV radiation penetrates the top semitransparent SC-SWNT layer with low losses (10-20%) and excites photocarriers within the n-ZnO layer in close proximity to the p-SC-SWNT/n-ZnO interface, where electron-hole pairs are efficiently separated by a high built-in electric field associated with the heterojunction.

  11. A Blind High-Capacity Wavelet-Based Steganography Technique for Hiding Images into other Images

    Directory of Open Access Journals (Sweden)

    HAMAD, S.

    2014-05-01

    Full Text Available The flourishing field of Steganography is providing effective techniques to hide data into different types of digital media. In this paper, a novel technique is proposed to hide large amounts of image data into true colored images. The proposed method employs wavelet transforms to decompose images in a way similar to the Human Visual System (HVS for more secure and effective data hiding. The designed model can blindly extract the embedded message without the need to refer to the original cover image. Experimental results showed that the proposed method outperformed all of the existing techniques not only imperceptibility but also in terms of capacity. In fact, the proposed technique showed an outstanding performance on hiding a secret image whose size equals 100% of the cover image while maintaining excellent visual quality of the resultant stego-images.

  12. A blind transform based approach for the detection of isolated astrophysical pulses

    Science.gov (United States)

    Alkhweldi, Marwan; Schmid, Natalia A.; Prestage, Richard M.

    2017-06-01

    This paper presents a blind algorithm for the automatic detection of isolated astrophysical pulses. The detection algorithm is applied to spectrograms (also known as "filter bank data" or "the (t,f) plane"). The detection algorithm comprises a sequence of three steps: (1) a Radon transform is applied to the spectrogram, (2) a Fourier transform is applied to each projection parametrized by an angle, and the total power in each projection is calculated, and (3) the total power of all projections above 90° is compared to the total power of all projections below 90° and a decision in favor of an astrophysical pulse present or absent is made. Once a pulse is detected, its Dispersion Measure (DM) is estimated by fitting an analytically developed expression for a transformed spectrogram containing a pulse, with varying value of DM, to the actual data. The performance of the proposed algorithm is numerically analyzed.

  13. Blind Ambition

    Science.gov (United States)

    Olson, Catherine Applefeld

    2009-01-01

    No matter how dedicated they may be, some teachers are daunted by extreme challenges. Carol Agler, music director at the Ohio State School for the Blind (OSSB), is not one of those teachers. Since joining the OSSB staff 11 years ago, Agler has revived the school's long-dormant band program and created its first marching band. Next January, she…

  14. 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.

  15. Visible blind ultraviolet photodetector based on CH3NH3PbCl3 thin film.

    Science.gov (United States)

    Wang, Wenzhen; Xu, Haitao; Cai, Jiang; Zhu, Jiabin; Ni, Chaowei; Hong, Feng; Fang, Zebo; Xu, Fuzong; Cui, Siwei; Xu, Run; Wang, Linjun; Xu, Fei; Huang, Jian

    2016-04-18

    We report a prototypical device of CH3NH3PbCl3 film ultraviolet photodetectors that were fabricated with a coplanar metal-semiconductor-metal Au interdigital electrode configuration. Pure phase CH3NH3PbCl3 films with a good crystallinity were formed by a hybrid sequential deposition process featured with inter-diffusion of PbCl2 and CH3NH3Cl upon annealing. The CH3NH3PbCl3 film photodetector exhibits a high responsivity of 7.56 A /W at 360 nm, a ultraviolet/visible rejection ratio (R360 nm/R500 nm) was about two orders of magnitude and fast response speed with a rising time of 170 μs and a decay time of 220 μs. All the above results demonstrate CH3NH3PbCl3 film photodetector as a competitive candidate in the application of visible blind UV detectors.

  16. A highly efficacious pediculicide based on dimeticone: Randomized observer blinded comparative trial

    Directory of Open Access Journals (Sweden)

    Oliveira Fabíola A

    2008-09-01

    Full Text Available Abstract Background Infestation with the human head louse (Pediculus humanus capitis occurs worldwide. Existing treatment options are limited, and reports of resistance to commonly used pediculicides have been increasing. In this trial we assessed the efficacy of a product containing a high (92% concentration of the silicone oil dimeticone (identical in composition to NYDA®, as compared to a 1% permethrin lotion. Methods Randomized, controlled, observer blinded clinical trial. Participants were recruited from a poor urban neighbourhood in Brazil where pediculosis capitis was highly prevalent. To minimize reinfestation during the trial, participants (145 children aged 5–15 years with head lice infestations were transferred to a holiday resort outside the endemic area for a period of 9 days. Two applications of dimeticone or 1% permethrin were done, seven days apart. Outcome measures were defined as cure (absence of vital head lice after first application and before and after second applications, degree of itching, cosmetic acceptability, and clinical pathology. Results Overall cure rates were: day 2 – dimeticone 94.5% (95% CI: 86.6% – 98.5% and permethrin 66.7% (95% CI: 54.6% – 77.3%; p Conclusion The dimeticone product is a safe and highly efficacious pediculicide. Due to its physical mode of action (interruption of the lice's oxygen supply of the central nervous system, development of resistance is unlikely. Trial registration Current Controlled Trials ISRCTN15117709.

  17. Stereo Camera Based Virtual Cane System with Identifiable Distance Tactile Feedback for the Blind

    Science.gov (United States)

    Kim, Donghun; Kim, Kwangtaek; Lee, Sangyoun

    2014-01-01

    In this paper, we propose a new haptic-assisted virtual cane system operated by a simple finger pointing gesture. The system is developed by two stages: development of visual information delivery assistant (VIDA) with a stereo camera and adding a tactile feedback interface with dual actuators for guidance and distance feedbacks. In the first stage, user's pointing finger is automatically detected using color and disparity data from stereo images and then a 3D pointing direction of the finger is estimated with its geometric and textural features. Finally, any object within the estimated pointing trajectory in 3D space is detected and the distance is then estimated in real time. For the second stage, identifiable tactile signals are designed through a series of identification experiments, and an identifiable tactile feedback interface is developed and integrated into the VIDA system. Our approach differs in that navigation guidance is provided by a simple finger pointing gesture and tactile distance feedbacks are perfectly identifiable to the blind. PMID:24932864

  18. Robust and Blind 3D Mesh Watermarking in Spatial Domain Based on Faces Categorization and Sorting

    Science.gov (United States)

    Molaei, Amir Masoud; Ebrahimnezhad, Hossein; Sedaaghi, Mohammad Hossein

    2016-06-01

    In this paper, a 3D watermarking algorithm in spatial domain is presented with blind detection. In the proposed method, a negligible visual distortion is observed in host model. Initially, a preprocessing is applied on the 3D model to make it robust against geometric transformation attacks. Then, a number of triangle faces are determined as mark triangles using a novel systematic approach in which faces are categorized and sorted robustly. In order to enhance the capability of information retrieval by attacks, block watermarks are encoded using Reed-Solomon block error-correcting code before embedding into the mark triangles. Next, the encoded watermarks are embedded in spherical coordinates. The proposed method is robust against additive noise, mesh smoothing and quantization attacks. Also, it is stout next to geometric transformation, vertices and faces reordering attacks. Moreover, the proposed algorithm is designed so that it is robust against the cropping attack. Simulation results confirm that the watermarked models confront very low distortion if the control parameters are selected properly. Comparison with other methods demonstrates that the proposed method has good performance against the mesh smoothing attacks.

  19. ZnO based visible-blind UV photodetector by spray pyrolysis

    Science.gov (United States)

    Inamdar, S. I.; Ganbavle, V. V.; Rajpure, K. Y.

    2014-12-01

    Zinc oxide (ZnO) metal-semiconductor-metal ultraviolet photodetectors were fabricated by economical spray pyrolysis method. The devices have been characterized to investigate the effect of precursor solution concentration on the photoconductive properties of ZnO. The structural, morphological and optical properties of the ZnO thin films were studied using different techniques. The crystal structure, size and lattice parameters have been estimated by X-ray diffraction (XRD) analysis. The UV photodetector device prepared using 0.1 M solution concentration exhibits low dark current and high UV photocurrent of about 134 μA at 5 V bias at 365 nm peak wavelength. The surface morphology and the surface roughness have been studied by AFM analysis. UV-Vis measurements have been used to study the effect of solution concentration on absorption spectra and hence on the band gap. The present device shows fast response in UV region of electromagnetic spectrum and shows almost no response to visible light. The characteristic times for rise and fall of the photocurrent device were 12 s and 9 s respectively. This devices are providing a simple and economical way to fabricate high-performance 'visible-blind' UV detectors and promising for use in large-area UV-A photodetector applications.

  20. A Robust Non-Blind Watermarking Technique for Color Video Based on Combined DWT-DFT Transforms and SVD Technique

    Directory of Open Access Journals (Sweden)

    Nandeesh B

    2014-08-01

    Full Text Available The rise of popularity of Digital video in the past decade has been tremendous thereby leading to malicious copying and distribution. So the need for preservation of ownership and in tackling copyright issues has become an imminent issue. Digital Video Watermarking has been in existence as a solution for this. The paper proposes a non-blind watermarking technique based on combined DWT-DFT transforms using singular values of SVD matrix in YCbCr color space. The technique uses Fibonacci series for selection of frames to enhance security and thereby maintaining quality of original video. Watermark encryption is done by scrambling the watermark using Arnold transform. Geometric and non-geometric attacks on watermarked video have been performed to test the robustness of the proposed technique. Quality of watermarked video is measured using PSNR and NC gives the similarity between extracted and the original watermark.

  1. Population-based survey of prevalence, causes, and risk factors for blindness and visual impairment in an aging Chinese metropolitan population

    Science.gov (United States)

    Hu, Jian-Yan; Yan, Liang; Chen, Yong-Dong; Du, Xin-Hua; Li, Ting-Ting; Liu, De-An; Xu, Dong-Hong; Huang, Yi-Min; Wu, Qiang

    2017-01-01

    AIM To assess the prevalence, causes, and risk factors for blindness and visual impairment among elderly (≥60 years of age) Chinese people in a metropolitan area of Shanghai, China. METHODS Random cluster sampling was conducted to identify participants among residents ≥60 years of age living in the Xietu Block, Xuhui District, Shanghai, China. Presenting visual acuity (PVA) and best-corrected visual acuity (BCVA) were checked by the Early Treatment Diabetic Retinopathy Study (ETDRS) visual chart. All eligible participants underwent a comprehensive eye examination. Blindness and visual impairment were defined according to World Health Organization (WHO) criteria. RESULTS A total of 4190 persons (1688 men and 2502 women) participated in the study, and the response rate was 91.1%. Based on PVA, the prevalence of blindness was 1.1% and that of visual impairment was 7.6%. Based on BCVA, the prevalence of blindness and visual impairment decreased to 0.9% and 3.9%, respectively. Older (≥80 years of age) women, with low educational levels and smoking habits, exhibited a significantly greater chance for blindness and visual impairment than did those with high educational levels and no smoking habits (PAMD). CONCLUSION Our findings help to identify the population in need of intervention, to highlight the need for additional eye healthcare services in urban China. PMID:28149791

  2. Zero-Power-Consumption Solar-Blind Photodetector Based on β-Ga2O3/NSTO Heterojunction.

    Science.gov (United States)

    Guo, Daoyou; Liu, Han; Li, Peigang; Wu, Zhenping; Wang, Shunli; Cui, Can; Li, Chaorong; Tang, Weihua

    2017-01-18

    A solar-blind photodetector based on β-Ga2O3/NSTO (NSTO = Nb:SrTiO3) heterojunctions were fabricated for the first time, and its photoelectric properties were investigated. The device presents a typical positive rectification in the dark, while under 254 nm UV light illumination, it shows a negative rectification, which might be caused by the generation of photoinduced electron-hole pairs in the β-Ga2O3 film layer. With zero bias, that is, zero power consumption, the photodetector shows a fast photoresponse time (decay time τd = 0.07 s) and the ratio Iphoto/Idark ≈ 20 under 254 nm light illumination with a light intensity of 45 μW/cm(2). Such behaviors are attributed to the separation of photogenerated electron-hole pairs driven by the built-in electric field in the depletion region of β-Ga2O3 and the NSTO interface, and the subsequent transport toward corresponding electrodes. The photocurrent increases linearly with increasing the light intensity and applied bias, while the response time decreases with the increase of the light intensity. Under -10 V bias and 45 μW/cm(2) of 254 nm light illumination, the photodetector exhibits a responsivity Rλ of 43.31 A/W and an external quantum efficiency of 2.1 × 10(4) %. The photo-to-electric conversion mechanism in the β-Ga2O3/NSTO heterojunction photodetector is explained in detail by energy band diagrams. The results strongly suggest that a photodetector based on β-Ga2O3 thin-film heterojunction structure can be practically used to detect weak solar-blind signals because of its high photoconductive gain.

  3. Blind Source Separation Algorithm Based on Correntropy%基于相关熵的盲源分离算法

    Institute of Scientific and Technical Information of China (English)

    成昊; 唐斌

    2013-01-01

    A blind source separation algorithm based on correntropy is presented. Unlike the traditional independent component analysis (ICA) method which utilizes the forth-order statistics or temporal structure to achieve the blind source separation. This algorithm is motivated from the notion of correntropy in the information theoretic learning, utilizing the even statistics implied in correntropy. The cost function is established according to the relationship between the parametric centered correntropy and the independence measure, and then minimized by using the optimization algorithm to acquire the demixing matrix and separate the signal. Simulations show that the performance is better than the traditional ICA method when separating the mixture of the super-Gaussian source and sub-Gaussian source.%  提出了基于相关熵的盲源分离算法。与传统独立成分分析(ICA)方法利用四阶统计量或时间结构的盲源分离不同,该算法从信息理论学习中的相关熵概念出发,利用相关熵中蕴涵的各偶数阶统计信息,通过参数化中心相关熵与独立性测度的关系,建立代价函数,并通过优化算法对其进行寻优,从而得到解混矩阵并分离出源信号。仿真结果表明,在分离超高斯混合源和次高斯混合源时,分离性能优于传统的ICA方法。

  4. [Effects of a neuropsychology program based on mindfulness on Alzheimer's disease: randomized double-blind clinical study].

    Science.gov (United States)

    Quintana Hernández, Domingo Jesús; Miró Barrachina, María Teresa; Ibáñez Fernández, Ignacio; del Pino, Angelo Santana; García Rodríguez, Javie r; Hernández, Jaime Rojas

    2014-01-01

    The purpose of this research was to assess effects of a mindfulness based neuropsychological intervention on the clinical course of Alzheimer's disease. A two year randomized and double blind clinical trial was conducted on 127 probable Alzheimer's disease patients, according to NINCDS-ADRDA scale. Patients were grouped into three experimental groups (cognitive stimulation, progressive muscular relaxation, and mindfulness) plus a control group. All participants were receiving donepezil. Cognitive skills were assessed with CAMCOG and MMSE, functional area with RDRS-2, and NPI was used for psychopathology screening. Three treatment sessions per week were carried out for two years, and follow up measurements were taken every six months. The global cognitive function, functionality and behavioral disorders measurements indicated that patients from the experimental group based on mindfulness were stable during the two years, while patients from the control group, as well as the other experimental groups, showed a mild but significant worsening of their mental capacities. The mindfulness based neuropsychological program showed better cognitive and functional stability, as well as significant improvement in the psychopathological condition of mild to moderate Alzheimer' patients. These results support the idea that a mindfulness based intervention can produce a clinically relevant improvement in the treatment of dementia. More research is needed to confirm these data. Copyright © 2013 SEGG. Published by Elsevier Espana. All rights reserved.

  5. Primary care based randomised, double blind trial of amoxicillin versus placebo for acute otitis media in children aged under 2 years

    NARCIS (Netherlands)

    Damoiseaux, RAMJ; van Balen, FAM; Hoes, AW; Verheij, TJM; de Melker, RA

    2000-01-01

    Objective To determine the effect of antibiotic treatment for acute otitis media in children between 6 months and 2 years of age. Design Practice based, double blind, randomised, placebo controlled trial. Setting 53 general practices in the Netherlands. Subjects 240 children aged 6 months to 2 years

  6. 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...

  7. 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.

  8. Denoising of Ictal EEG Data Using Semi-Blind Source Separation Methods Based on Time-Frequency Priors.

    Science.gov (United States)

    Hajipour Sardouie, Sepideh; Bagher Shamsollahi, Mohammad; Albera, Laurent; Merlet, Isabelle

    2015-05-01

    Removing muscle activity from ictal ElectroEncephaloGram (EEG) data is an essential preprocessing step in diagnosis and study of epileptic disorders. Indeed, at the very beginning of seizures, ictal EEG has a low amplitude and its morphology in the time domain is quite similar to muscular activity. Contrary to the time domain, ictal signals have specific characteristics in the time-frequency domain. In this paper, we use the time-frequency signature of ictal discharges as a priori information on the sources of interest. To extract the time-frequency signature of ictal sources, we use the Canonical Correlation Analysis (CCA) method. Then, we propose two time-frequency based semi-blind source separation approaches, namely the Time-Frequency-Generalized EigenValue Decomposition (TF-GEVD) and the Time-Frequency-Denoising Source Separation (TF-DSS), for the denoising of ictal signals based on these time-frequency signatures. The performance of the proposed methods is compared with that of CCA and Independent Component Analysis (ICA) approaches for the denoising of simulated ictal EEGs and of real ictal data. The results show the superiority of the proposed methods in comparison with CCA and ICA.

  9. Evidence-Based Counterterrorism or Flying Blind? How to Understand and Achieve What Works

    Directory of Open Access Journals (Sweden)

    Rebecca Freese

    2014-02-01

    Full Text Available Many counterterrorism efforts in last decades, and especially since 9/11, have been plagued with doubts as to whether or not they actually make us safer. Unfortunately, the terrorism research that is needed to better plan and evaluate counterterrorism efforts has suffered from both a lack of sufficient rigour and lack of influence on policy-making. This article reviews the state of terrorism research and evidence-based practice in counterterrorism, and the challenges to both. A framework is proposed for the kind of research that needs to be conducted in order to develop evidence-based counterterrorism programs as well as the subsequent evaluative research on existing programs as part of a wider quality improvement program. The argument is made that there is a need for a concrete infrastructure of evidence-based practice and quality improvement in counterterrorism to ensure the best outcomes for national security. The components of a full spectrum quality improvement program in counterterrorism are described. Insights are garnered from the field of medicine, which has recently delved full force into evidence-based practice and quality improvement.

  10. Comparison of Training, Blind and Semi Blind Equalizers in MIMO Fading Systems Using Capacity as Measure

    OpenAIRE

    Kavitha, Veeraruna; Sharma, Vinod

    2005-01-01

    Semi blind/blind equalizers are believed to work unsatisfactorily in fading MIMO channels compared to training based methods, due to slow convergence or high computational complexity. We revisit this issue. Defining a 'composite' channel for each equalizer, we compare the three algorithms based on the capacity of this channel. We show that, in a Rician (with line of sight, LOS) environment, semi blind/blind algorithms outperform training equalizers, but in Rayleigh channels, it is better to u...

  11. Flavor misattribution: A novel approach to improving compliance and blinding in food-based clinical interventions

    Directory of Open Access Journals (Sweden)

    Julianne E. Bierwirth

    2015-06-01

    Conclusion: Effective beverages worked by invoking “flavor misattribution”, wherein a food (broccoli extract with an objectionable sensory characteristic was paired with a vector in which that characteristic was an acceptable component of the vector’s flavor profile. Further development of this concept with an unlimited palate could be used to develop optimal carriers for food product development and/or to refine the approach for clinical trials based upon local taste preferences.

  12. Verification of the new detection method for irradiated spices based on microbial survival by collaborative blind trial

    Science.gov (United States)

    Miyahara, M.; Furuta, M.; Takekawa, T.; Oda, S.; Koshikawa, T.; Akiba, T.; Mori, T.; Mimura, T.; Sawada, C.; Yamaguchi, T.; Nishioka, S.; Tada, M.

    2009-07-01

    An irradiation detection method using the difference of the radiation sensitivity of the heat-treated microorganisms was developed as one of the microbiological detection methods of the irradiated foods. This detection method is based on the difference of the viable cell count before and after heat treatment (70 °C and 10 min). The verification by collaborative blind trial of this method was done by nine inspecting agencies in Japan. The samples used for this trial were five kinds of spices consisting of non-irradiated, 5 kGy irradiated, and 7 kGy irradiated black pepper, allspice, oregano, sage, and paprika, respectively. As a result of this collaboration, a high percentage (80%) of the correct answers was obtained for irradiated black pepper and allspice. However, the method was less successful for irradiated oregano, sage, and paprika. It might be possible to use this detection method for preliminary screening of the irradiated foods but further work is necessary to confirm these findings.

  13. Verification of the new detection method for irradiated spices based on microbial survival by collaborative blind trial

    Energy Technology Data Exchange (ETDEWEB)

    Miyahara, M. [National Institute of Health Sciences, 1-18-1 Kamiyoga, Setagaya-Ku, Tokyo (Japan)], E-mail: mfuruta@b.s.osakafu-u.ac.jp; Furuta, M. [Osaka Prefecture University, 1-2 Gakuen-Cho, Naka-ku, Sakai, 599-8570 Osaka (Japan); Takekawa, T. [Nuclear Fuel Industries Ltd., 950-1 Asashiro-Nishi, Kumatori-Cho, Sennan-Gun, Osaka (Japan); Oda, S. [Japan Food Research Laboratories, 52-1 Motoyoyogi-Cho, Sibuya-Ku, Tokyo (Japan); Koshikawa, T. [Japan Radio Isotope Association, 121-19 Toriino, Koka, Shiga (Japan); Akiba, T. [Japan Food Hygiene Association, 2-5-47 Tadao, Machida, Tokyo (Japan); Mori, T. [Tokyo Kenbikyo-In Foundation, 44-1 Nihonbashi, Hakozaki-Cho, Chuo-Ku, Tokyo (Japan); Mimura, T. [Japan Oilstuff Inspector' s Corporation, 26-1 Kaigandori 5-Chome, Naka-Ku, Yokohama (Japan); Sawada, C. [Japan Frozen Foods Inspection Corp., 2-13-45 Fukuura, Kanazawa-Ku, Yokohama (Japan); Yamaguchi, T. [Japan Electron Beam Irradiation Service Co., Ltd., 4-16 Midorigahara, Tukuba, Ibaraki (Japan); Nishioka, S. [Mycotoxin Inspection Corp., 15 Daikokufuto, Turumi-Ku, Yokohama (Japan); Tada, M. [Chugoku Gakuen University, 83 Niwase, Okayama (Japan)

    2009-07-15

    An irradiation detection method using the difference of the radiation sensitivity of the heat-treated microorganisms was developed as one of the microbiological detection methods of the irradiated foods. This detection method is based on the difference of the viable cell count before and after heat treatment (70 deg. C and 10 min). The verification by collaborative blind trial of this method was done by nine inspecting agencies in Japan. The samples used for this trial were five kinds of spices consisting of non-irradiated, 5 kGy irradiated, and 7 kGy irradiated black pepper, allspice, oregano, sage, and paprika, respectively. As a result of this collaboration, a high percentage (80%) of the correct answers was obtained for irradiated black pepper and allspice. However, the method was less successful for irradiated oregano, sage, and paprika. It might be possible to use this detection method for preliminary screening of the irradiated foods but further work is necessary to confirm these findings.

  14. Semi-blind independent component analysis of fMRI based on real-time fMRI system.

    Science.gov (United States)

    Ma, Xinyue; Zhang, Hang; Zhao, Xiaojie; Yao, Li; Long, Zhiying

    2013-05-01

    Real-time functional magnetic resonance imaging (fMRI) is a type of neurofeedback tool that enables researchers to train individuals to actively gain control over their brain activation. Independent component analysis (ICA) based on data-driven model is seldom used in real-time fMRI studies due to large time cost, though it has been very popular to offline analysis of fMRI data. The feasibility of performing real-time ICA (rtICA) processing has been demonstrated by previous study. However, rtICA was only applied to analyze single-slice data rather than full-brain data. In order to improve the performance of rtICA, we proposed semi-blind real-time ICA (sb-rtICA) for our real-time fMRI system by adding regularization of certain estimated time courses using the experiment paradigm information to rtICA. Both simulated and real-time fMRI experiment were conducted to compare the two approaches. Results from simulated and real full-brain fMRI data demonstrate that sb-rtICA outperforms rtICA in robustness, computational time and spatial detection power. Moreover, in contrast to rtICA, the first component estimated by sb-rtICA tends to be the target component in more sliding windows.

  15. 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.

  16. On Blind MIMO System Identification Based on Second-Order Cyclic Statistics

    Directory of Open Access Journals (Sweden)

    K. Sabri

    2008-01-01

    Full Text Available This letter introduces a new frequency domain approach for either MIMO System Identification or Source Separation of convolutive mixtures in cyclostationary context. We apply the joint diagonalization algorithm to a set of cyclic spectral density matrices of the measurements to identify the mixing system at each frequency up to permutation and phase ambiguity matrices. An efficient algorithm to overcome the frequency dependent permutations and to recover the phase, even for non-minimum-phase channels, based on cyclostationarity is also presented. The new approach exploits the fact that each input has a different and specific cyclic frequency. A comparison with an existing MIMO method is proposed.

  17. Blind RSSD-Based Indoor Localization with Confidence Calibration and Energy Control.

    Science.gov (United States)

    Zou, Tengyue; Lin, Shouying; Li, Shuyuan

    2016-05-31

    Indoor localization based on wireless sensor networks (WSNs) is an important field of research with numerous applications, such as elderly care, miner security, and smart buildings. In this paper, we present a localization method based on the received signal strength difference (RSSD) to determine a target on a map with unknown transmission information. To increase the accuracy of localization, we propose a confidence value for each anchor node to indicate its credibility for participating in the estimation. An automatic calibration device is designed to help acquire the values. The acceleration sensor and unscented Kalman filter (UKF) are also introduced to reduce the influence of measuring noise in the application. Energy control is another key point in WSN systems and may prolong the lifetime of the system. Thus, a quadtree structure is constructed to describe the region correlation between neighboring areas, and the unnecessary anchor nodes can be detected and set to sleep to save energy. The localization system is implemented on real-time Texas Instruments CC2430 and CC2431 embedded platforms, and the experimental results indicate that these mechanisms achieve a high accuracy and low energy cost.

  18. Blind RSSD-Based Indoor Localization with Confidence Calibration and Energy Control

    Directory of Open Access Journals (Sweden)

    Tengyue Zou

    2016-05-01

    Full Text Available Indoor localization based on wireless sensor networks (WSNs is an important field of research with numerous applications, such as elderly care, miner security, and smart buildings. In this paper, we present a localization method based on the received signal strength difference (RSSD to determine a target on a map with unknown transmission information. To increase the accuracy of localization, we propose a confidence value for each anchor node to indicate its credibility for participating in the estimation. An automatic calibration device is designed to help acquire the values. The acceleration sensor and unscented Kalman filter (UKF are also introduced to reduce the influence of measuring noise in the application. Energy control is another key point in WSN systems and may prolong the lifetime of the system. Thus, a quadtree structure is constructed to describe the region correlation between neighboring areas, and the unnecessary anchor nodes can be detected and set to sleep to save energy. The localization system is implemented on real-time Texas Instruments CC2430 and CC2431 embedded platforms, and the experimental results indicate that these mechanisms achieve a high accuracy and low energy cost.

  19. Pathophysiological interference with neurovascular coupling - when imaging based on hemoglobin might go blind

    Directory of Open Access Journals (Sweden)

    Ute Lindauer

    2010-10-01

    Full Text Available Assessing neuronal activity by noninvasive functional brain imaging techniques which are based on the hemodynamic response depends totally on the physiological cascade of metabolism and blood flow. At present, functional brain imaging with near infrared spectroscopy (NIRS or BOLD-fMRI is widely used in cognitive neuroscience in healthy subjects where neurovascular coupling and cerebrovascular reactivity can be assumed to be intact. Local activation studies as well as studies investigating functional connectivity between brain regions of the resting brain provide a rapidly increasing body of knowledge on brain function in humans and animals. Furthermore, functional NIRS and MRI techniques are increasingly being used in patients with severe brain diseases and this use might gain more and more importance for establishing their use in the clinical routine. However, more and more experimental evidence shows that changes in baseline physiological parameters, pharmacological interventions or disease-related vascular changes may significantly alter the normal response of blood flow and blood oxygenation and thus may lead to misinterpretation of neuronal activity. In this article we present examples of recent experimental findings on pathophysiological changes of neurovascular coupling parameters in animals and discuss their potential implications for functional imaging based on hemodynamic signals such as fNIRS or BOLD-fMRI. To enable correct interpretation of neuronal activity by vascular signals, future research needs to deepen our understanding of the basic mechanisms of neurovascular coupling and the specific characteristics of disturbed neurovascular coupling in the diseased brain.

  20. CAPS satellite spread spectrum communication blind multi-user detecting system based on chaotic sequences

    Institute of Scientific and Technical Information of China (English)

    LEI LiHua; SHI HuLi; MA GuanYi

    2009-01-01

    Multiple Path Interference (MPI) and Multiple Access Interference (MAI) are Important factors that affect the performance of Chinese Area Positioning System (CAPS),These problems can be solved by using spreading sequences with ideal properties and multi-user detectors.Chaotic sequences based on Chebyshev map are studied and the satellite communication system model is set up to investigate the application of chaotic sequences for CAPS in this paper,Simulation results show that chaotic sequences have desirable correlation properties and it is easy to generate a large number of chaotic sequences with good security.It has great practical value to apply chaotic sequences to CAPS together with multi-user detecting technology and the system performance can be improved greatly.

  1. 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.

  2. CAPS satellite spread spectrum communication blind multi-user detecting system based on chaotic sequences

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Multiple Path Interference (MPI) and Multiple Access Interference (MAI) are important factors that affect the performance of Chinese Area Positioning System (CAPS). These problems can be solved by using spreading sequences with ideal properties and multi-user detectors. Chaotic sequences based on Chebyshev map are studied and the satellite communication system model is set up to investigate the application of chaotic sequences for CAPS in this paper. Simulation results show that chaotic sequences have desirable correlation properties and it is easy to generate a large number of chaotic sequences with good security. It has great practical value to apply chaotic sequences to CAPS together with multi-user detecting technology and the system performance can be improved greatly.

  3. An Efficient Scheme for Sensitive Message Transmission using Blind Signcryption

    OpenAIRE

    Awasthi, Amit K; Lal, Sunder

    2005-01-01

    Blind signature schemes enable a useful protocol that guarantee the anonymity of the participants while Signcryption offers authentication of message and confidentiality of messages at the same time and more efficiently. In this paper, we present a blind signcryption scheme that combines the functionality of blind signature and signcryption. This blind Signcryption is useful for applications that are based on anonymity untracebility and unlinkability.

  4. Should we have blind faith in bioinformatics software? Illustrations from the SNAP web-based tool.

    Directory of Open Access Journals (Sweden)

    Sébastien Robiou-du-Pont

    Full Text Available Bioinformatics tools have gained popularity in biology but little is known about their validity. We aimed to assess the early contribution of 415 single nucleotide polymorphisms (SNPs associated with eight cardio-metabolic traits at the genome-wide significance level in adults in the Family Atherosclerosis Monitoring In earLY Life (FAMILY birth cohort. We used the popular web-based tool SNAP to assess the availability of the 415 SNPs in the Illumina Cardio-Metabochip genotyped in the FAMILY study participants. We then compared the SNAP output with the Cardio-Metabochip file provided by Illumina using chromosome and chromosomal positions of SNPs from NCBI Human Genome Browser (Genome Reference Consortium Human Build 37. With the HapMap 3 release 2 reference, 201 out of 415 SNPs were reported as missing in the Cardio-Metabochip by the SNAP output. However, the Cardio-Metabochip file revealed that 152 of these 201 SNPs were in fact present in the Cardio-Metabochip array (false negative rate of 36.6%. With the more recent 1000 Genomes Project release, we found a false-negative rate of 17.6% by comparing the outputs of SNAP and the Illumina product file. We did not find any 'false positive' SNPs (SNPs specified as available in the Cardio-Metabochip by SNAP, but not by the Cardio-Metabochip Illumina file. The Cohen's Kappa coefficient, which calculates the percentage of agreement between both methods, indicated that the validity of SNAP was fair to moderate depending on the reference used (the HapMap 3 or 1000 Genomes. In conclusion, we demonstrate that the SNAP outputs for the Cardio-Metabochip are invalid. This study illustrates the importance of systematically assessing the validity of bioinformatics tools in an independent manner. We propose a series of guidelines to improve practices in the fast-moving field of bioinformatics software implementation.

  5. Ultrasensitive Self-Powered Solar-Blind Deep-Ultraviolet Photodetector Based on All-Solid-State Polyaniline/MgZnO Bilayer.

    Science.gov (United States)

    Chen, Hongyu; Yu, Pingping; Zhang, Zhenzhong; Teng, Feng; Zheng, Lingxia; Hu, Kai; Fang, Xiaosheng

    2016-09-05

    A high sensitivity self-powered solar-blind photodetector is successfully constructed based on the polyaniline/MgZnO bilayer. The maximum responsivity of the photodetector is 160 μA W(-1) at 250 nm under 0 V bias. The device also exhibits a high on/off ratio of ≈10(4) under 250 nm illumination at a relatively weak light intensity of 130 μW cm(-2) without any power.

  6. 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.

  7. Video-based instructions for surgical hand disinfection as a replacement for conventional tuition? A randomised, blind comparative study

    Science.gov (United States)

    Weber, Uwe; Constantinescu, Mihai A.; Woermann, Ulrich; Schmitz, Felix; Schnabel, Kai

    2016-01-01

    Introduction: Various different learning methods are available for planning tuition regarding the introduction to surgical hand disinfection. These learning methods should help to organise and deal with this topic. The use of a video film is an alternative to conventional tuition due to the real presentation possibilities of practical demonstration. Objective: This study examines by way of comparison which form of communication is more effective for learning and applying surgical hand disinfection for medical students in their first year of studies: video-based instruction or conventional tuition. Methodology: A total of 50 first-year medical students were randomly allocated either to the “Conventional Instruction” (CI) study group or to the “Video-based Instruction” (VI) study group. The conventional instruction was carried out by an experienced nurse preceptor/nurse educator for the operating theatre who taught the preparatory measures and the actual procedure in a two-minute lesson. The second group watched a two-minute video sequence with identical content. Afterwards, both groups demonstrated practically the knowledge they had acquired at an individual practical test station. The quality (a) of the preparation and (b) of the procedure as well as (c) the quality of the results was assessed by 6 blind experts using a check list. The acceptability of the respective teaching method was also asked about using a questionnaire. Results: The group performance did not differ either in the preparation (t=-78, p<0.44) or in the quality (t=-99, p<0.34). With respect to performance, it was possible to demonstrate a strong treatment effect. In the practical (t=-3.33, p<0.002, d=0.943) and in the total score (t=-2.65, p<0.011, d=0.751), the group with video-based instruction achieved a significantly better result. In response to the question as to which of the two learning methods they would prefer, the significant majority (60.4%) of students stated video

  8. Video-based instructions for surgical hand disinfection as a replacement for conventional tuition? A randomised, blind comparative study

    Directory of Open Access Journals (Sweden)

    Weber, Uwe

    2016-08-01

    Full Text Available Introduction: Various different learning methods are available for planning tuition regarding the introduction to surgical hand disinfection. These learning methods should help to organise and deal with this topic. The use of a video film is an alternative to conventional tuition due to the real presentation possibilities of practical demonstration. Objective: This study examines by way of comparison which form of communication is more effective for learning and applying surgical hand disinfection for medical students in their first year of studies: video-based instruction or conventional tuition. Methodology: A total of 50 first-year medical students were randomly allocated either to the “Conventional Instruction” (CI study group or to the “Video-based Instruction” (VI study group. The conventional instruction was carried out by an experienced nurse preceptor/nurse educator for the operating theatre who taught the preparatory measures and the actual procedure in a two-minute lesson. The second group watched a two-minute video sequence with identical content. Afterwards, both groups demonstrated practically the knowledge they had acquired at an individual practical test station. The quality (a of the preparation and (b of the procedure as well as (c the quality of the results was assessed by 6 blind experts using a check list. The acceptability of the respective teaching method was also asked about using a questionnaire.Results: The group performance did not differ either in the preparation (=-78, <0.44 or in the quality (=-99, <0.34. With respect to performance, it was possible to demonstrate a strong treatment effect. In the practical (=-3.33, <0.002, =0.943 and in the total score (=-2.65, <0.011, =0.751, the group with video-based instruction achieved a significantly better result. In response to the question as to which of the two learning methods they would prefer, the significant majority (60.4% of students stated video instruction

  9. Do TETRA (Airwave) Base Station Signals Have a Short-Term Impact on Health and Well-Being? A Randomized Double-Blind Provocation Study

    Science.gov (United States)

    Wallace, Denise; Eltiti, Stacy; Ridgewell, Anna; Garner, Kelly; Russo, Riccardo; Sepulveda, Francisco; Walker, Stuart; Quinlan, Terence; Dudley, Sandra; Maung, Sithu; Deeble, Roger; Fox, Elaine

    2010-01-01

    Background “Airwave” is the new communication system currently being rolled out across the United Kingdom for the police and emergency services, based on the Terrestrial Trunked Radio Telecommunications System (TETRA). Some police officers have complained about skin rashes, nausea, headaches, and depression as a consequence of using their Airwave handsets. In addition, a small subgroup in the population self-report being sensitive to electromagnetic fields (EMFs) in general. Objectives We conducted a randomized double-blind provocation study to establish whether short-term exposure to a TETRA base station signal has an impact on the health and well-being of individuals with self-reported “electrosensitivity” and of participants who served as controls. Methods Fifty-one individuals with self-reported electrosensitivity and 132 age- and sex-matched controls participated in an open provocation test; 48 sensitive and 132 control participants went on to complete double-blind tests in a fully screened semianechoic chamber. Heart rate, skin conductance, and blood pressure readings provided objective indices of short-term physiological response. Visual analog scales and symptom scales provided subjective indices of well-being. Results We found no differences on any measure between TETRA and sham (no signal) under double-blind conditions for either controls or electrosensitive participants, and neither group could detect the presence of a TETRA signal at rates greater than chance (50%). When conditions were not double blind, however, the self-reported electrosensitive individuals did report feeling worse and experienced more severe symptoms during TETRA compared with sham. Conclusions Our findings suggest that the adverse symptoms experienced by electrosensitive individuals are due to the belief of harm from TETRA base stations rather than to the low-level EMF exposure itself. PMID:20075020

  10. Performance and Complexity Analysis of Blind FIR Channel Identification Algorithms Based on Deterministic Maximum Likelihood in SIMO Systems

    DEFF Research Database (Denmark)

    De Carvalho, Elisabeth; Omar, Samir; Slock, Dirk

    2013-01-01

    We analyze two algorithms that have been introduced previously for Deterministic Maximum Likelihood (DML) blind estimation of multiple FIR channels. The first one is a modification of the Iterative Quadratic ML (IQML) algorithm. IQML gives biased estimates of the channel and performs poorly at lo...

  11. Ultra-low threshold avalanche gain from solar-blind photodetector based on graded-band-gap-cubic-MgZnO.

    Science.gov (United States)

    Xie, Xiuhua; Zhang, Zhenzhong; Li, Binghui; Wang, Shuangpeng; Shen, Dezhen

    2015-12-14

    A larger ratio of conduction-band offset to valence-band offset is the unique character for Mg(x)Zn(1-x)O alloys. For this reason, it is feasible to build a quasi-electric forces, caused by the spatial gradient of the conduction edge, exerting on the electrons. In this paper, a novel graded band gap cubic-MgZnO-based solar-blind photodetector is successfully fabricated from Graded-Band-Gap-Cubic-MgZnO/i-MgO/p-Si heterojunction, via changing stoichiometry spatial gradient. Due to quasi-electric fields in non-uniform MgZnO, the multiple carriers are generated under ultra-low threshold bias voltage. The photodetector showed high performance, namely, high responsivity, quantum efficiency, high sensitivity and selectivity towards the solar-blind spectrum, and fast response times.

  12. Kurtosis-based blind source extraction of complex non-circular signals with application in EEG artifact removal in real-time.

    Science.gov (United States)

    Javidi, Soroush; Mandic, Danilo P; Took, Clive Cheong; Cichocki, Andrzej

    2011-01-01

    A new class of complex domain blind source extraction algorithms suitable for the extraction of both circular and non-circular complex signals is proposed. This is achieved through sequential extraction based on the degree of kurtosis and in the presence of non-circular measurement noise. The existence and uniqueness analysis of the solution is followed by a study of fast converging variants of the algorithm. The performance is first assessed through simulations on well understood benchmark signals, followed by a case study on real-time artifact removal from EEG signals, verified using both qualitative and quantitative metrics. The results illustrate the power of the proposed approach in real-time blind extraction of general complex-valued sources.

  13. Blind identification of full-field vibration modes from video measurements with phase-based video motion magnification

    Science.gov (United States)

    Yang, Yongchao; Dorn, Charles; Mancini, Tyler; Talken, Zachary; Kenyon, Garrett; Farrar, Charles; Mascareñas, David

    2017-02-01

    Experimental or operational modal analysis traditionally requires physically-attached wired or wireless sensors for vibration measurement of structures. This instrumentation can result in mass-loading on lightweight structures, and is costly and time-consuming to install and maintain on large civil structures, especially for long-term applications (e.g., structural health monitoring) that require significant maintenance for cabling (wired sensors) or periodic replacement of the energy supply (wireless sensors). Moreover, these sensors are typically placed at a limited number of discrete locations, providing low spatial sensing resolution that is hardly sufficient for modal-based damage localization, or model correlation and updating for larger-scale structures. Non-contact measurement methods such as scanning laser vibrometers provide high-resolution sensing capacity without the mass-loading effect; however, they make sequential measurements that require considerable acquisition time. As an alternative non-contact method, digital video cameras are relatively low-cost, agile, and provide high spatial resolution, simultaneous, measurements. Combined with vision based algorithms (e.g., image correlation, optical flow), video camera based measurements have been successfully used for vibration measurements and subsequent modal analysis, based on techniques such as the digital image correlation (DIC) and the point-tracking. However, they typically require speckle pattern or high-contrast markers to be placed on the surface of structures, which poses challenges when the measurement area is large or inaccessible. This work explores advanced computer vision and video processing algorithms to develop a novel video measurement and vision-based operational (output-only) modal analysis method that alleviate the need of structural surface preparation associated with existing vision-based methods and can be implemented in a relatively efficient and autonomous manner with little

  14. Virtual Environments for the Transfer of Navigation Skills in the Blind: A Comparison of Directed Instruction Versus Video Game Based Learning Approaches

    Directory of Open Access Journals (Sweden)

    Erin C Connors

    2014-05-01

    Full Text Available For profoundly blind individuals, navigating in an unfamiliar building can represent a significant challenge. We investigated the use of an audio-based, virtual environment called Audio-based Environment Simulator (AbES that can be explored for the purposes of learning the layout of an unfamiliar, complex indoor environment. Furthermore, we compared two modes of interaction with AbES. In one group, blind participants implicitly learned the layout of a target environment while playing an exploratory, goal-directed video game. By comparison, a second group was explicitly taught the same layout following a standard route and instructions provided by a sighted facilitator. As a control, a third group interacted with AbES while playing an exploratory, goal-directed video game however, the explored environment did not correspond to the target layout. Following interaction with AbES, a series of route navigation tasks were carried out in the virtual and physical building represented in the training environment to assess the transfer of acquired spatial information. We found that participants from both modes of interaction were able to transfer the spatial knowledge gained as indexed by their successful route navigation performance. This transfer was not apparent in the control participants. Most notably, the game-based learning strategy was also associated with enhanced performance when participants were required to find alternate routes and short cuts within the target building suggesting that a ludic-based training approach may provide for a more flexible mental representation of the environment. Furthermore, outcome comparisons between early and late blind individuals suggested that greater prior visual experience did not have a significant effect on overall navigation performance following training. Finally, performance did not appear to be associated with other factors of interest such as age, gender, and verbal memory recall. We conclude that the

  15. Blind system identification

    OpenAIRE

    Abed-Meriam, Karim; Qui, Wanzhi; Hua, Yingbo

    1997-01-01

    Blind system identification (BSI) is a fundamental signal processing technology aimed at retrieving a system's unknown information from its output only. This technology has a wide range of possible applications such as mobile communications, speech reverberation cancellation, and blind image restoration. This paper reviews a number of recently developed concepts and techniques for BSI, which include the concept of blind system identifiability in a deterministic framework, the blind techniques...

  16. Blind Detection Algorithm Based on Quantum Genetic Optimization%基于量子遗传优化的盲检测算法

    Institute of Scientific and Technical Information of China (English)

    蔡晴红; 于舒娟; 张昀

    2013-01-01

    Quantum genetic algorithm,as the combination of the quantum computing theory and the principle of genetic algorithm,is a new global optimization algorithm,which has stronger capability in the optimization,faster convergence and shorter time in computing. It has already been widely used in many areas. It proposes a blind equalization model which sends BPSK signal based on SIMO system. Use projection operator of complement to construct the cost function,based on which quantum genetic algorithm is applied to optimize to ob-tain the best sequence of estimation. The algorithm simulation results show that the proposed blind detection algorithm based on quantum genetic optimization has rapid convergence speed,is able to successfully achieve blind detection,has a certain value.%  量子遗传算法(Quantum Genetic Algorithm)作为量子计算理论和遗传算法原理相结合的一种新兴的全局优化算法,因算法具有寻优能力强、收敛速度快和计算时间短的特点,在许多领域都得到了广泛应用。文中首先给出基于SIMO系统的BPSK发送信号盲检测模型,利用补投影算子构造盲检测优化代价函数,在此基础上利用量子遗传算法进行优化,获得最佳估计序列。算法性能仿真表明,文中提出的基于量子遗传优化的盲检测算法收敛速度快、能够成功实现盲检测,具有一定的应用价值。

  17. QR分解卡尔曼盲自适应多用户检测算法%Kalman blind adaptive multiuser detector based on QR factor

    Institute of Scientific and Technical Information of China (English)

    张志富; 裴军

    2015-01-01

    码分多址(Code-Division Multiple-Access,CDMA)系统中,采用盲多用户检测算法抑制多址干扰(Multiple Access Interference,MAI)和“远-近”效应(Near-Far effect)的影响,是CDMA技术研究热点之一。为避免基于卡尔曼(Kalman)滤波的多用户检测算法中,协方差矩阵失去非负定性而面临的数值稳定性问题,提出利用QR分解方法重新构造系统模型协方差阵,建立一种收敛速度更快、数值鲁棒性更好的卡尔曼盲自适应多用户检测算法。仿真结果表明,该算法具有较好的抗多址干扰和抗“远-近”效应能力。%Blind multi-user detection methods in Code-Division Multiple-Access(CDMA)system are used to eliminate the Multiple Access Interference(MAI)and the Near-Far effect. For microprocessor or DSP has a limit word length, blind multi-user detection based on Kalman filter must face the problem of numeric stability. A new method based on QR factor is used in the blind multi-user detection based on Kalman filter. Simulation results show that this method is efficient in MAI and Near-Far effect elimination.

  18. Virtual environments for the transfer of navigation skills in the blind: a comparison of directed instruction vs. video game based learning approaches

    Science.gov (United States)

    Connors, Erin C.; Chrastil, Elizabeth R.; Sánchez, Jaime; Merabet, Lotfi B.

    2014-01-01

    For profoundly blind individuals, navigating in an unfamiliar building can represent a significant challenge. We investigated the use of an audio-based, virtual environment called Audio-based Environment Simulator (AbES) that can be explored for the purposes of learning the layout of an unfamiliar, complex indoor environment. Furthermore, we compared two modes of interaction with AbES. In one group, blind participants implicitly learned the layout of a target environment while playing an exploratory, goal-directed video game. By comparison, a second group was explicitly taught the same layout following a standard route and instructions provided by a sighted facilitator. As a control, a third group interacted with AbES while playing an exploratory, goal-directed video game however, the explored environment did not correspond to the target layout. Following interaction with AbES, a series of route navigation tasks were carried out in the virtual and physical building represented in the training environment to assess the transfer of acquired spatial information. We found that participants from both modes of interaction were able to transfer the spatial knowledge gained as indexed by their successful route navigation performance. This transfer was not apparent in the control participants. Most notably, the game-based learning strategy was also associated with enhanced performance when participants were required to find alternate routes and short cuts within the target building suggesting that a ludic-based training approach may provide for a more flexible mental representation of the environment. Furthermore, outcome comparisons between early and late blind individuals suggested that greater prior visual experience did not have a significant effect on overall navigation performance following training. Finally, performance did not appear to be associated with other factors of interest such as age, gender, and verbal memory recall. We conclude that the highly interactive

  19. Virtual environments for the transfer of navigation skills in the blind: a comparison of directed instruction vs. video game based learning approaches.

    Science.gov (United States)

    Connors, Erin C; Chrastil, Elizabeth R; Sánchez, Jaime; Merabet, Lotfi B

    2014-01-01

    For profoundly blind individuals, navigating in an unfamiliar building can represent a significant challenge. We investigated the use of an audio-based, virtual environment called Audio-based Environment Simulator (AbES) that can be explored for the purposes of learning the layout of an unfamiliar, complex indoor environment. Furthermore, we compared two modes of interaction with AbES. In one group, blind participants implicitly learned the layout of a target environment while playing an exploratory, goal-directed video game. By comparison, a second group was explicitly taught the same layout following a standard route and instructions provided by a sighted facilitator. As a control, a third group interacted with AbES while playing an exploratory, goal-directed video game however, the explored environment did not correspond to the target layout. Following interaction with AbES, a series of route navigation tasks were carried out in the virtual and physical building represented in the training environment to assess the transfer of acquired spatial information. We found that participants from both modes of interaction were able to transfer the spatial knowledge gained as indexed by their successful route navigation performance. This transfer was not apparent in the control participants. Most notably, the game-based learning strategy was also associated with enhanced performance when participants were required to find alternate routes and short cuts within the target building suggesting that a ludic-based training approach may provide for a more flexible mental representation of the environment. Furthermore, outcome comparisons between early and late blind individuals suggested that greater prior visual experience did not have a significant effect on overall navigation performance following training. Finally, performance did not appear to be associated with other factors of interest such as age, gender, and verbal memory recall. We conclude that the highly interactive

  20. Blindness and severe visual impairment in pupils at schools for the blind in Burundi.

    Science.gov (United States)

    Ruhagaze, Patrick; Njuguna, Kahaki Kimani Margaret; Kandeke, Lévi; Courtright, Paul

    2013-01-01

    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. 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 before the age of 16 years. Overall, 117 pupils who became visually impaired before 16 years of age were examined. Of these, 109 (93.2%) were blind or severely visually impaired. The major anatomical cause of blindness or severe visual impairment was cornea pathology/phthisis (23.9%), followed by lens pathology (18.3%), uveal lesions (14.7%) and optic nerve lesions (11.9%). In the majority of pupils with blindness or severe visual impairment, the underlying etiology of visual loss was unknown (74.3%). More than half of the pupils with lens related blindness had not had surgery; among those who had surgery, outcomes were generally poor. The causes identified indicate the importance of continuing preventive public health strategies, as well as the development of specialist pediatric ophthalmic services in the management of childhood blindness in Burundi. The geographic distribution of pupils at the schools for the blind indicates a need for community-based programs to identify and refer children in need of services.

  1. Blind Reconciliation

    CERN Document Server

    Martinez-Mateo, Jesus; Martin, Vicente

    2012-01-01

    Information reconciliation is a crucial procedure in the classical post-processing of quantum key distribution (QKD). Poor reconciliation efficiency, revealing more information than strictly needed, may compromise the maximum attainable distance, while poor performance of the algorithm limits the practical throughput in a QKD device. Historically, reconciliation has been mainly done using close to minimal information disclosure but heavily interactive procedures, like Cascade, or using less efficient but also less interactive -just one message is exchanged- procedures, like the ones based in low-density parity-check (LDPC) codes. The price to pay in the LDPC case is that good efficiency is only attained for very long codes and in a very narrow range centered around the quantum bit error rate (QBER) that the code was designed to reconcile, thus forcing to have several codes if a broad range of QBER needs to be catered for. Real world implementations of these methods are thus very demanding, either on computati...

  2. User-centered Technologies For Blind Children

    Directory of Open Access Journals (Sweden)

    Jaime Sánchez

    2008-01-01

    Full Text Available The purpose of this paper is to review, summarize, and illustrate research work involving four audio-based games created within a user-centered design methodology through successive usability tasks and evaluations. These games were designed by considering the mental model of blind children and their styles of interaction to perceive and process data and information. The goal of these games was to enhance the cognitive development of spatial structures, memory, haptic perception, mathematical skills, navigation and orientation, and problem solving of blind children. Findings indicate significant improvements in learning and cognition from using audio-based tools specially tailored for the blind. That is, technologies for blind children, carefully tailored through user-centered design approaches, can make a significant contribution to cognitive development of these children. This paper contributes new insight into the design and implementation of audio-based virtual environments to facilitate learning and cognition in blind children.

  3. The reconnaissance and early-warning optical system design for dual field of space-based "solar blind ultraviolet"

    Science.gov (United States)

    Wang, Wen-cong; Jin, Dong-dong; Shao, Fei; Hu, Hui-jun; Shi, Yu-feng; Song, Juan; Zhang, Yu-tu; Yong, Liu

    2016-07-01

    With the development of modern technology, especially the development of information technology at high speed, the ultraviolet early warning system plays an increasingly important role. In the modern warfare, how to detect the threats earlier, prevent and reduce the attack of precision-guided missile has become a new challenge. Because the ultraviolet warning technology has high environmental adaptability, the low false alarm rate, small volume and other advantages, in the military field applications it has been developed rapidly. According to current application demands for solar blind ultraviolet detection and warning, this paper proposes a reconnaissance and early-warning optical system, which covers solar blind ultraviolet (250nm-280nm) and dual field. This structure takes advantage of a narrow field of view and long focal length optical system to achieve the target object detection, uses wide-field and short focal length optical system to achieve early warning of the target object. It makes use of an ultraviolet beam-splitter to achieve the separation of two optical systems. According to the detector and the corresponding application needs of two visual field of the optical system, the calculation and optical system design were completed. After the design, the MTF of the two optical system is more than 0.8@39lp/mm. A single pixel energy concentration is greater than 80%.

  4. Elimination of blinding trachoma in China.

    Science.gov (United States)

    Liu, T; Liang, Q; Hu, A; Feng, G; Wang, N; Peng, X; Baudouin, C; Labbé, A

    2016-12-01

    To present the change in the prevalence of blindness caused by trachoma between 1987 and 2006 by secondary data analysis based on two China National Sample Surveys on Disability (CNSSD). Secondary data analysis was performed on two China National Sample Surveys on Disability (CNSSD), which were national representative household surveys conducted in 1987 and 2006. The prevalence of blindness caused by trachoma was estimated by 10-year age group. In addition, the proportion of various causes of blindness was evaluated. The geographical distribution of blindness caused by trachoma both in 1987 and 2006 was analyzed in order to visualize the hot spots of blinding trachoma in China. The prevalence of blindness caused by trachoma in China decreased from 51.5/100,000 in 1987 to 17.6/100,000 in 2006. In addition, the proportion of blindness attributed to trachoma also decreased from 10.1% (1987) to 0.9% (2006). Moreover, the prevalence of blindness caused by trachoma was over 200/100,000 in 2.2% of sampled counties in 2006 as compared to 8.6% in 1987. The hot spots of blinding trachoma were shown to be limited to underdeveloped mountain areas in Hubei and Guizhou provinces. Although blinding trachoma is no longer the leading cause of blindness in China since the 2000's, the prevalence of trachoma should still be monitored in some underdeveloped mountain areas. Therefore, health organization must continue to fight against blinding trachoma in underdeveloped areas. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  5. The Blind as "Ordinary People".

    Science.gov (United States)

    Feinman, Saul

    1978-01-01

    Based on a paper presented at the 1977 Western Social Science Association Meeting in Denver, Colorado, the article reports on a study that compared major demographic features of a sample of 70 legally blind adults with the sighted adult sample studied in the 1975 National Opinion Research Center General Social Survey. (Author/DLS)

  6. An E-Voting Scheme Based on Proxy Blind Signature%一个基于代理盲签名的电子选举方案

    Institute of Scientific and Technical Information of China (English)

    张碧军; 何明星

    2013-01-01

      分析了一种基于改进离散对数问题的电子选举方案及其在代理授权和盲签名方面存在的安全漏洞,针对此方案在安全性和无收据性方面的不足进行了改进,提出了一种基于代理盲签名的电子选举方案,并对新方案的合法性、匿名性、可验证性、无收据性等性能进行了分析。%The paper analyzes an E-voting scheme based on improved DLP , finds its security flaw in authorized agent and blind signature, and improves it according to security problems and no receipt .Then the authors propose a more efficient and more secure E-voting scheme based on proxy blind signature .The security,anonymity,verifiability and no receipt of the new scheme are analyzed .

  7. 基于Schnorr签名的多重部分盲签名%Multi-Partial Blind Signature of Schnorr Signature-Based

    Institute of Scientific and Technical Information of China (English)

    晁瑜婷; 张秉儒

    2012-01-01

    Multi-Blind signature is made of many signers,they sign themselves at the same time.This will cooperate with every signers.Based onEL-Gamal signature,the Schnorrdigital signature is improved.Compared with EL-Gamal signature,it has some characteristics of small amount of calculation and speed.Based on the Schnorr signature the multi-partial blind signature has been the applying platform,the kind of generalizations of the signature is for med.%多重盲签名由多个签名人同时对消息进行各自的盲签名,须共同配合才能完成.Schnorr数字签名,是基于EL-Gamal签名改进的,它和EL-Gamal签名相比较,具有计算量小、速度快等特点.文章基于Schnorr签名的一般化,将其应用于多重部分盲签名里,形成多种多样的签名的一般化形式.

  8. Aggregated data from two double-blind base station provocation studies comparing individuals with idiopathic environmental intolerance with attribution to electromagnetic fields and controls.

    Science.gov (United States)

    Eltiti, Stacy; Wallace, Denise; Russo, Riccardo; Fox, Elaine

    2015-02-01

    Data from two previous studies were aggregated to provide a statistically powerful test of whether exposure to electromagnetic fields (EMFs) produced by telecommunication base stations negatively affects well-being in individuals who report idiopathic environmental illness with attribution to electromagnetic fields (IEI-EMF) and control participants. A total of 102 IEI-EMF and 237 controls participated in open provocation trials and 88 IEI-EMF and 231 controls went on to complete double-blind trials in which they were exposed to EMFs from a base station emitting either a Global System for Mobile Communication and Universal Mobile Telecommunications System or a Terrestrial Trunked Radio Telecommunications System signal. Both experiments included a comparison sham condition. Visual analog and symptom scales measured subjective well-being. Results showed that IEI-EMF participants reported lower levels of well-being during real compared to sham exposure during open provocation, but not during double-blind trials. Additionally, participants reported lower levels of well-being during high compared to low load trials and this did not interact with radiofrequency-EMF exposure. These findings are consistent with a growing body of literature indicating there is no causal relationship between short-term exposure to EMFs and subjective well-being in members of the public whether or not they report perceived sensitivity to EMFs.

  9. High-performance solar-blind ultraviolet photodetector based on electrospun TiO2-ZnTiO3 heterojunction nano- wires

    Institute of Scientific and Technical Information of China (English)

    Haining Chong[1,2; Guodong Wei[2; Huilin Hou[2; Huijun Yang[1; Minghui Shang[2; Fengmei Gao[2; Weiyou Yang[2; Guozhen Shen[3

    2015-01-01

    High-performance solar-blind UV (ultraviolet) photodetectors (PDs) based on low-dimension semiconducting nanostructures with high sensitivity, excellent cycle stability, and the ability to operate in harsh environments are critical for solar observations, space communication, UV astronomy, and missile tracking. In this study, TiO2-ZnTiO3 heterojunction nanowire-based PDs are successfully developed and used to detect solar-blind UV light. A photoconductive analysis indicates that the fabricated PDs are sensitive to UV illumination, with high sensitivity, good stability, and high reproducibility. Further analysis indicates that the rich existence of grain boundaries within the TiO2-ZnTiO3 nanowire can greatly decrease the dark current and recombination of the electron-hole pairs and thereby significantly increase the device's photosensitivity, spectra responsivity (1.1 ~ 106), and external quantum efficiency (4.3 ~ 108 %). Moreover, the PDs exhibit good photodetective performance with fast photoresponse and recovery and excellent thermal stability at temperatures as high as 175 ℃. According to these results, TiO2-ZnTiO3 heterojunction nanowires exhibit great potential for applications in high-performance optical electronics and PDs, particularly next-generation photodetectors with the ability to operate in harsh environments.

  10. A Recursive Blind IdentificationAlgorithm Based on SIMO System%一种基于SIMO系统的递推盲辨识算法

    Institute of Scientific and Technical Information of China (English)

    张亮; 张洪渊; 史习智

    2001-01-01

    Conventional blind channel identification algorithms are based onchannel outputs and knowledge of the probabilistic model of channel input. However, there may not be sufficient data to obtain accurate estimates of certain statistics. In order to avoid this drawback, a new blind identification method is presented by using the recursive least square (RLS) method to solve the XLTK equation. It reduces the required eomputation memory for blind deconvolution of SIMO-FIR systems. A simple method derived from an identity commonly found in polynumial theory is used to deconvolve the system input. The experimental results show the validity of the method.%传统的盲辨识算法是基于通道输入的统计模型和通道输出,然而在对输入的统计特性进行准确估计时需要大量的数据。为了避免这种缺点,本文提出了一种单输入多输出(SIMO)线性时不变有限单位冲击响应(FIR)系统的盲辨识最小二乘算法,利用递推最小二乘算法求解这类算法中的XLTK方程,大大降低了算法对计算存储量的要求。在盲辨识的基础上,利用多项式互质的一个判别定理,通过解卷积求出SIMO-FIR系统输入,最后通过实验验证了算法的有效性。

  11. Objective evaluation of acute adverse events and image quality of gadolinium-based contrast agents (gadobutrol and gadobenate dimeglumine) by blinded evaluation. Pilot study.

    Science.gov (United States)

    Semelka, Richard C; Hernandes, Mateus de A; Stallings, Clifton G; Castillo, Mauricio

    2013-01-01

    The purpose was to objectively evaluate a recently FDA-approved gadolinium-based contrast agent (GBCA) in comparison to our standard GBCA for acute adverse events and image quality by blinded evaluation. Evaluation was made of a recently FDA-approved GBCA, gadobutrol (Gadavist; Bayer), in comparison to our standard GBCA, gadobenate dimeglumine (MultiHance; Bracco), in an IRB- and HIPAA-compliant study. Both the imaging technologist and patient were not aware of the brand of the GBCA used. A total of 59 magnetic resonance studies were evaluated (59 patients, 31 men, 28 women, age range of 5-85 years, mean age of 52 years). Twenty-nine studies were performed with gadobutrol (22 abdominal and 7 brain studies), and 30 studies were performed with gadobenate dimeglumine (22 abdominal and 8 brain studies). Assessment was made of acute adverse events focusing on objective observations of vomiting, hives, and moderate and severe reactions. Adequacy of enhancement was rated as poor, fair and good by one of two experienced radiologists who were blinded to the type of agent evaluated. No patient experienced acute adverse events with either agent. The target minor adverse events of vomiting or hives, and moderate and severe reactions were not observed in any patient. Adequacy of enhancement was rated as good for both agents in all patients. Objective, blinded evaluation is feasible and readily performable for the evaluation of GBCAs. This proof-of-concept study showed that both GBCAs evaluated exhibited consistent good image quality and no noteworthy adverse events. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. 一种基于混沌振子的DSSS信号盲检测方法%Blind Detection of DSSS Signal based on Chaos Oscillator

    Institute of Scientific and Technical Information of China (English)

    蒋涛; 熊刚

    2015-01-01

    直接序列扩频通信是一种具有强保密性和抗干扰性的先进通信体制,对DSSS信号的检测具有重要作用。将非线性科学中的混沌理论应用于DSSS信号的盲检测,结合DSSS信号特征研究了一种利用混沌振子进行检测的方法。首先分析了洛伦兹混沌振子检测周期信号的原理和DSSS信号模型,然后构造出了一个基于混沌振子阵列的盲检测系统,可实现对低信噪比条件下对DSSS信号的盲检测。最后,通过计算机仿真结果表明了该方法的有效性,且性能优于过去的一些算法。%Direct sequence spread spectrum communication, as an advanced communications system with strong confidentiality and anti-interference, plays an important role in DSSS signal detection. Chaos theory in nonlinear science is applied to blind detection of DSSS signal, and in combination with DSSS signal characteristics, a detection method with chaotic oscillator for signal detection is developed. Firstly, the theory of Lorenz chaos oscillator array for signal detection and DSSS signal mode are analyzed, then a blind detection system based on chaos oscillator array is constructed,thus to implement blind detection of DSSS signal under low SNR,finally, computer simulation indicates that this method is effective and is better in performance as compared with certain traditional methods.

  13. 基于多线性映射的无证书代理盲签名方案%Certificateless proxy blind signature scheme based on multilinear pairing

    Institute of Scientific and Technical Information of China (English)

    汤鹏志; 李彪; 李晓雄

    2012-01-01

    代理盲签名方案不能防止密钥生成中心不诚信行为,存在伪造签名的隐患.文章在无证书公钥密码学体系下,通过多密钥中心共同生成用户密钥,运用多线性映射的技术,提出一种基于多线性映射的代理盲签名方案.该方案满足代理盲签名协议的性质,同时可以防止单个密钥生成中心伪造签名.对该方案的正确性、安全性及攻击性进行了分析,结果表明,该方案具备较高的安全性,可以广泛应用于电子现金、电子银行和电子投票系统.%The proxy blind signature scheme can not prevent the bad faith conduct of key generation center, which may cause the forging signature. Under the certificateless public key cryptographic system, a proxy blind signature scheme based on multilinear pairing is proposed by generating the user's key through multikey center and using the technology of multilinear pairing. This scheme can suffice the property of proxy blind signature protocol, and prevent the forging signature of single key generation center. The correctness, security and attack analysis shows that the proposed scheme has high security, which can be widely used in electronic cash, banking and voting systems.

  14. Underdetermined DOA estimation and blind separation of non-disjoint sources in time-frequency domain based on sparse representation method

    Institute of Scientific and Technical Information of China (English)

    Xiang Wang; Zhitao Huang; Yiyu Zhou

    2014-01-01

    This paper deals with the blind separation of nonstation-ary sources and direction-of-arrival (DOA) estimation in the under-determined case, when there are more sources than sensors. We assume the sources to be time-frequency (TF) disjoint to a certain extent. In particular, the number of sources presented at any TF neighborhood is strictly less than that of sensors. We can identify the real number of active sources and achieve separation in any TF neighborhood by the sparse representation method. Compared with the subspace-based algorithm under the same sparseness assumption, which suffers from the extra noise effect since it can-not estimate the true number of active sources, the proposed algorithm can estimate the number of active sources and their cor-responding TF values in any TF neighborhood simultaneously. An-other contribution of this paper is a new estimation procedure for the DOA of sources in the underdetermined case, which combines the TF sparseness of sources and the clustering technique. Sim-ulation results demonstrate the validity and high performance of the proposed algorithm in both blind source separation (BSS) and DOA estimation.

  15. 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.

  16. Milk-based cornstarch porridge fortified with iron is effective in reducing anemia: a randomized, double-blind, placebo-controlled trial.

    Science.gov (United States)

    Arcanjo, Francisco Plácido Nogueira; Arcanjo, Cecília Costa; Arcanjo, Francisco Carlos Nogueira; Campos, Lício de Albuquerque; Amancio, Olga Maria Silverio; Braga, Josefina Aparecida Pellegrini

    2012-10-01

    This study evaluates the impact of a milk-based cornstarch porridge fortified with iron, in 4-year olds, compared with control on hemoglobin levels and anemia prevalence. This trial was a cluster-randomized, double-blind one, and used milk-based cornstarch porridge fortified with 10 mg elemental iron (FeSO(4)), daily, during 14 weeks, compared with control. The study population comprised 4-year-old preschoolers (n = 131). Mean hemoglobin values at baseline were found to be 10.6 ± 0.61 g dl(-1) for intervention group, and after intervention 11.5 ± 0.80 g/dl, p porridge fortified with ferrous sulfate increased hemoglobin levels and reduced anemia prevalence in 4-year-old preschoolers.

  17. Evaluation of a crataegus-based multiherb formula for dyslipidemia: a randomized, double-blind, placebo-controlled clinical trial.

    Science.gov (United States)

    Hu, Miao; Zeng, Weiwei; Tomlinson, Brian

    2014-01-01

    Background. We for the first time examined the effects of a multiherb formula containing Crataegus pinnatifida (1 g daily), Alisma orientalis, Stigma maydis, Ganoderma lucidum, Polygonum multiflorum, and Morus alba on plasma lipid and glucose levels in Chinese patients with dyslipidemia. Methods. In this randomized, double-blind, placebo-controlled study, 42 patients were randomized at a ratio of 1 : 1 to receive the herbal formula or placebo for 12 weeks and 40 patients completed the study. Lipid profiles, glucose, glycated haemoglobin (HbA1c), and laboratory safety parameters were performed before and after treatment. Results. The difference in the changes in low-density lipoprotein cholesterol (LDL-C) levels between placebo and active treatment (-9%) was significantly (P < 0.05) better with active treatment. HbA1c levels significantly decreased by -3.9% in the active treatment group, but the change was not significantly different from that with placebo (-1.1%) (P = 0.098). There were no apparent adverse effects or changes in laboratory safety parameters with either treatment. Conclusions. The multiherb formula had mild beneficial effects on plasma LDL-C after 12-weeks treatment in subjects with dyslipidemia without any noticeable adverse effects.

  18. Evaluation of a Crataegus-Based Multiherb Formula for Dyslipidemia: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial

    Directory of Open Access Journals (Sweden)

    Miao Hu

    2014-01-01

    Full Text Available Background. We for the first time examined the effects of a multiherb formula containing Crataegus pinnatifida (1 g daily, Alisma orientalis, Stigma maydis, Ganoderma lucidum, Polygonum multiflorum, and Morus alba on plasma lipid and glucose levels in Chinese patients with dyslipidemia. Methods. In this randomized, double-blind, placebo-controlled study, 42 patients were randomized at a ratio of 1 : 1 to receive the herbal formula or placebo for 12 weeks and 40 patients completed the study. Lipid profiles, glucose, glycated haemoglobin (HbA1c, and laboratory safety parameters were performed before and after treatment. Results. The difference in the changes in low-density lipoprotein cholesterol (LDL-C levels between placebo and active treatment (−9% was significantly (P<0.05 better with active treatment. HbA1c levels significantly decreased by −3.9% in the active treatment group, but the change was not significantly different from that with placebo (−1.1% (P=0.098. There were no apparent adverse effects or changes in laboratory safety parameters with either treatment. Conclusions. The multiherb formula had mild beneficial effects on plasma LDL-C after 12-weeks treatment in subjects with dyslipidemia without any noticeable adverse effects.

  19. Evaluation of a Crataegus-Based Multiherb Formula for Dyslipidemia: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial

    Science.gov (United States)

    Zeng, Weiwei; Tomlinson, Brian

    2014-01-01

    Background. We for the first time examined the effects of a multiherb formula containing Crataegus pinnatifida (1 g daily), Alisma orientalis, Stigma maydis, Ganoderma lucidum, Polygonum multiflorum, and Morus alba on plasma lipid and glucose levels in Chinese patients with dyslipidemia. Methods. In this randomized, double-blind, placebo-controlled study, 42 patients were randomized at a ratio of 1 : 1 to receive the herbal formula or placebo for 12 weeks and 40 patients completed the study. Lipid profiles, glucose, glycated haemoglobin (HbA1c), and laboratory safety parameters were performed before and after treatment. Results. The difference in the changes in low-density lipoprotein cholesterol (LDL-C) levels between placebo and active treatment (−9%) was significantly (P < 0.05) better with active treatment. HbA1c levels significantly decreased by −3.9% in the active treatment group, but the change was not significantly different from that with placebo (−1.1%) (P = 0.098). There were no apparent adverse effects or changes in laboratory safety parameters with either treatment. Conclusions. The multiherb formula had mild beneficial effects on plasma LDL-C after 12-weeks treatment in subjects with dyslipidemia without any noticeable adverse effects. PMID:24834096

  20. A method for extracting fetal ECG based on EMD-NMF single channel blind source separation algorithm.

    Science.gov (United States)

    He, Pengju; Chen, Xiaomeng

    2015-01-01

    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 algorithm to process single abdominal acquired signal. This algorithm decomposed single abdominal signal into multiple intrinsic mode function (IMF) utilizing empirical mode decomposition (EMD). Correlation matrix of IMF was calculated and independent ECG signal number was estimated using eigenvalue method. Nonnegative matrix was constructed according to determined number and decomposed IMF. Separation of MECG and FECG was achieved utilizing nonnegative matrix factorization (NMF). Experiments selected four channels man-made signal and two channels ECG to verify correctness and feasibility of 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.

  1. Visual Product Identification for Blind

    Directory of Open Access Journals (Sweden)

    Krutarth Majithia

    2015-12-01

    Full Text Available This project is developed to make the life of blind people easy. This is a camera based system to scan the barcode behind the image and read the description of the product with the help of Id stored in the barcode. This is very beneficial in case of finding out the description of packaged goods to the blind people and thus helping them in deciding to purchase a product or not especially which are packaged. This is because it becomes very difficult for the blind people to distinguish between the packaged goods. In order to use this system, all the user needs to do is capture the image on the product in the mobile phone which then resolves the barcode which means it scans the image to find out the Id stored. Thus this application really benefits blind and visually impaired people and thus making their work of identifying products easy. This is very easy to use and affordable as it requires a scanner to scan the barcode and a camera phone to take the picture of the image containing the barcode. This is now easy to implement as most of the mobile phones today have the required resolution in order to scan the barcode to identify the Id stored in it and read out the product description. This project can be implemented in any shopping mall, supermarket, Book stores, Medical stores etc.

  2. A New Blind 2D-RAKE Receiver Based on CMA Criteria for Spread Spectrum Systems Suitable for Software Defined Radio Architecture

    Science.gov (United States)

    Takayama, Kei; Kamiya, Yukihiro; Fujii, Takeo; Suzuki, Yasuo

    Spread Spectrum (SS) has been widely used for various wireless systems such as cellular systems, wireless local area network (LAN) and so on. Using multiple antennas at the receiver, two-dimensional (2D) RAKE is realized over the time- and the space-domain. However, it should be noted that the 2D-RAKE receiver must detect the bit timing prior to the RAKE combining. In case of deep fading, it is often difficult to detect it due to low signal-to-noise power ratio (SNR). To solve this problem, we propose a new blind 2D-RAKE receiver based on the constant modulus algorithm (CMA). Since it does not need a priori bit timing detection, it is possible to compensate frequency selective fading even in very low SNR environments. The proposed method is particularly suitable for the software defined radio (SDR) architecture. The performance of the proposed method is investigated through computer simulations.

  3. High-Quality Crystal Growth and Characteristics of AlGaN-Based Solar-Blind Distributed Bragg Reflectors with a Tri-layer Period Structure.

    Science.gov (United States)

    Chang, Jianjun; Chen, Dunjun; Yang, Lianhong; Liu, Yanli; Dong, Kexiu; Lu, Hai; Zhang, Rong; Zheng, Youdou

    2016-07-06

    To realize AlGaN-based solar-blind ultraviolet distributed Bragg reflectors (DBRs), a novel tri-layer AlGaN/AlInN/AlInGaN periodical structure that differs from the traditional periodically alternating layers of high- and low-refractive-index materials was proposed and grown on an Al0.5Ga0.5N template via metal-organic chemical vapour deposition. Because of the intentional design of the AlInGaN strain transition layer, a state-of-the-art DBR structure with atomic-level-flatness interfaces was achieved using an AlGaN template. The fabricated DBR exhibits a peak reflectivity of 86% at the centre wavelength of 274 nm and a stopband with a full-width at half-maximum of 16 nm.

  4. Blindness and vision loss

    Science.gov (United States)

    ... means you cannot see anything and DO NOT see light. (Most people who use the term "blindness" mean ... the vision loss. For long-term vision loss, see a low-vision specialist, who can help you learn to care for yourself and ... of vision; No light perception (NLP); Low vision; Vision loss and blindness ...

  5. "Color-Blind" Racism.

    Science.gov (United States)

    Carr, Leslie G.

    Examining race relations in the United States from a historical perspective, this book explains how the constitution is racist and how color blindness is actually a racist ideology. It is argued that Justice Harlan, in his dissenting opinion in Plessy v. Ferguson, meant that the constitution and the law must remain blind to the existence of race…

  6. Blind Pre-School.

    Science.gov (United States)

    Taylor, Billie, Comp.

    Articles pertinent to aiding the pre-school blind child are collected in this publication. Topics include discussion of attitudes and emotional reactions important for parents and teachers of blind children, and optimal development in regard to early motor behavior and emotional and social needs. Common areas of parental concern such as discipline…

  7. 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."

  8. 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)

  9. "Color-Blind" Racism.

    Science.gov (United States)

    Carr, Leslie G.

    Examining race relations in the United States from a historical perspective, this book explains how the constitution is racist and how color blindness is actually a racist ideology. It is argued that Justice Harlan, in his dissenting opinion in Plessy v. Ferguson, meant that the constitution and the law must remain blind to the existence of race…

  10. A Frequency Blind Deconvolution Algorithm Based on Parallel Factor Decomposition%基于平行因子分解的频域盲解卷积算法

    Institute of Scientific and Technical Information of China (English)

    李剑; 杨贤

    2012-01-01

    针对卷积混合盲分离问题,文章提出了一张基于张量平行因子分解的盲分离算法。该算法通过将接收信号的频域相关矩阵叠加成三阶张量,再对此三阶张量进行平行因子分解,最后利用基于K-neans聚类的全排列解模糊算法来完成无排列模糊的混合矩阵估计。通过仿真实验,计算分离信号与源信号的相似系数,结果表明提出的算法具有很好的分离效果。而且实现简单,可满足实际应用的要求。%To solve the problem of the blind separation of convolutive separation, this paper proposes an algorithm based on tensor parallel factor decomposition (PARAFAC). Firsdy the frequency domain correlation matrix group of the received signals is stacked in a third-order tensor. Then parallel factor decomposition of this tensor is performed. Finally estimation of the mixing matrix without frequency ambiguity is done using the all-permutations based on K-means algorithm. Simulation results show that the performance of the algorithm is provides good blind separation of convolutive mixture. Also it is relatively simple to implement, which can satisfy the demand of engineering application.

  11. Models for the blind

    DEFF Research Database (Denmark)

    Olsén, Jan-Eric

    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 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...

  12. Independent vector analysis based on overlapped cliques of variable width for frequency-domain blind signal separation

    Science.gov (United States)

    Lee, Intae; Jang, Gil-Jin

    2012-12-01

    A novel method is proposed to improve the performance of independent vector analysis (IVA) for blind signal separation of acoustic mixtures. IVA is a frequency-domain approach that successfully resolves the well-known permutation problem by applying a spherical dependency model to all pairs of frequency bins. The dependency model of IVA is equivalent to a single clique in an undirected graph; a clique in graph theory is defined as a subset of vertices in which any pair of vertices is connected by an undirected edge. Therefore, IVA imposes the same amount of statistical dependency on every pair of frequency bins, which may not match the characteristics of real-world signals. The proposed method allows variable amounts of statistical dependencies according to the correlation coefficients observed in real acoustic signals and, hence, enables more accurate modeling of statistical dependencies. A number of cliques constitutes the new dependency graph so that neighboring frequency bins are assigned to the same clique, while distant bins are assigned to different cliques. The permutation ambiguity is resolved by overlapped frequency bins between neighboring cliques. For speech signals, we observed especially strong correlations across neighboring frequency bins and a decrease in these correlations with an increase in the distance between bins. The clique sizes are either fixed, or determined by the reciprocal of the mel-frequency scale to impose a wider dependency on low-frequency components. Experimental results showed improved performances over conventional IVA. The signal-to-interference ratio improved from 15.5 to 18.8 dB on average for seven different source locations. When we varied the clique sizes according to the observed correlations, the stability of the proposed method increased with a large number of cliques.

  13. 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。

  14. 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.

  15. 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...

  16. Self-Powered Solar-Blind Photodetector with Fast Response Based on Au/β-Ga2O3 Nanowires Array Film Schottky Junction.

    Science.gov (United States)

    Chen, Xing; Liu, Kewei; Zhang, Zhenzhong; Wang, Chunrui; Li, Binghui; Zhao, Haifeng; Zhao, Dongxu; Shen, Dezhen

    2016-02-17

    Because of the direct band gap of 4.9 eV, β-Ga2O3 has been considered as an ideal material for solar-blind photodetection without any bandgap tuning. Practical applications of the photodetectors require fast response speed, high signal-to-noise ratio, low energy consumption and low fabrication cost. Unfortunately, most reported β-Ga2O3-based photodetectors usually possess a relatively long response time. In addition, the β-Ga2O3 photodetectors based on bulk, the individual 1D nanostructure, and the film often suffer from the high cost, the low repeatability, and the relatively large dark current, respectively. In this paper, a Au/β-Ga2O3 nanowires array film vertical Schottky photodiode is successfully fabricated by a simple thermal partial oxidation process. The device exhibits a very low dark current of 10 pA at -30 V with a sharp cutoff at 270 nm. More interestingly, the 90-10% decay time of our device is only around 64 μs, which is much quicker than any other previously reported β-Ga2O3-based photodetectors. Besides, the self-powering, the excellent stability and the good reproducibility of Au/β-Ga2O3 nanowires array film photodetector are helpful to its commercialization and practical applications.

  17. Efficacy of alginate-based reflux suppressant and magnesium-aluminium antacid gel for treatment of heartburn in pregnancy: a randomized double-blind controlled trial

    Science.gov (United States)

    Meteerattanapipat, Pontip; Phupong, Vorapong

    2017-01-01

    The aim of this study was to compare the therapeutic efficacy of alginate-based reflux suppressant and magnesium-aluminium antacid gel for treatment of heartburn in pregnancy. A double-blinded, randomized, controlled trial was conducted. One hundred pregnant women at less than 36 weeks gestation with heartburn at least twice per week were randomized to either alginate-based reflux suppressant or to magnesium-aluminium antacid gel. Details of heartburn were recorded before beginning the treatment and the second week of study. Primary outcome measure was the improvement of heartburn frequency after treatment and secondary outcome were the improvement of heartburn intensity, quality of life, maternal satisfaction, maternal side effects, pregnancy and neonatal outcomes. There was no difference between treatment and control groups in improvement of heartburn frequency (80% vs 88%, p = 0.275), 50% reduction of frequency of heartburn (56% vs 52%, p = 0.688), improvement of heartburn intensity (92% vs 92%, p = 1.000) and 50% reduction of heartburn intensity (68% vs 80% cases, p = 0.075). There were also no significant differences in quality of life, maternal satisfaction, maternal side effects, pregnancy and neonatal outcomes. Alginate-based reflux suppressant was not different from magnesium-aluminium antacid gel in the treatment of heartburn in pregnancy. PMID:28317885

  18. Combined transcranial direct current stimulation and home-based occupational therapy for upper limb motor impairment following intracerebral hemorrhage: a double-blind randomized controlled trial.

    Science.gov (United States)

    Mortensen, Jesper; Figlewski, Krystian; Andersen, Henning

    2016-01-01

    To investigate the combined effect of transcranial direct current stimulation (tDCS) and home-based occupational therapy on activities of daily living (ADL) and grip strength, in patients with upper limb motor impairment following intracerebral hemorrhage (ICH). A double-blind randomized controlled trial with one-week follow-up. Patients received five consecutive days of occupational therapy at home, combined with either anodal (n = 8) or sham (n = 7) tDCS. The primary outcome was ADL performance, which was assessed with the Jebsen-Taylor test (JTT). Both groups improved JTT over time (p occupational therapy provided greater improvements in grip strength compared with occupational therapy alone. tDCS is a promising add-on intervention regarding training of upper limb motor impairment. It is well tolerated by patients and can easily be applied for home-based training. Larger studies with long-term follow-up are needed to further explore possible effects of tDCS in patients with ICH. Five consecutive days of tDCS combined with occupational therapy provided greater improvements in grip strength compared with occupational therapy alone. tDCS is well tolerated by patients and can easily be applied for home-based rehabilitation.

  19. The efficacy of early initiated, supervised, progressive resistance training compared to unsupervised, home-based exercise after unicompartmental knee arthroplasty: a single-blinded randomized controlled trial.

    Science.gov (United States)

    Jørgensen, Peter B; Bogh, Søren B; Kierkegaard, Signe; Sørensen, Henrik; Odgaard, Anders; Søballe, Kjeld; Mechlenburg, Inger

    2017-01-01

    To examine if supervised progressive resistance training was superior to home-based exercise in rehabilitation after unicompartmental knee arthroplasty. Single blinded, randomized clinical trial. Surgery, progressive resistance training and testing was carried out at Aarhus University Hospital and home-based exercise was carried out in the home of the patient. Fifty five patients were randomized to either progressive resistance training or home-based exercise. Patients were randomized to either progressive resistance training (home based exercise five days/week and progressive resistance training two days/week) or control group (home based exercise seven days/week). Preoperative assessment, 10-week (primary endpoint) and one-year follow-up were performed for leg extension power, spatiotemporal gait parameters and knee injury and osteoarthritis outcome score (KOOS). Forty patients (73%) completed 1-year follow-up. Patients in the progressive resistance training group participated in average 11 of 16 training sessions. Leg extension power increased from baseline to 10-week follow-up in progressive resistance training group (progressive resistance training: 0.28 W/kg, P= 0.01, control group: 0.01 W/kg, P=0.93) with no between-group difference. Walking speed and KOOS scores increased from baseline to 10-week follow-up in both groups with no between-group difference (six minutes walk test P=0.63, KOOS P>0.29). Progressive resistance training two days/week combined with home based exercise five days/week was not superior to home based exercise seven days/week in improving leg extension power of the operated leg.

  20. Blind loop syndrome

    Science.gov (United States)

    ... part of the stomach) and 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.

  1. Vision - night blindness

    Science.gov (United States)

    ... People with night blindness often have trouble seeing stars on a clear night or walking through a ... certain drugs Vitamin A deficiency (rare) Nontreatable causes: Birth defects Retinitis pigmentosa

  2. Visual Impairment, Including Blindness

    Science.gov (United States)

    ... Who Knows What? Survey Item Bank Search for: Visual Impairment, Including Blindness Links updated, April 2017 En ... doesn’t wear his glasses. Back to top Visual Impairments in Children Vision is one of our ...

  3. 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?

  4. 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.

  5. 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.

  6. 基于地理空间认知的盲人电子地图研究%Research of blind e-map based on geo-space cognition

    Institute of Scientific and Technical Information of China (English)

    付仲良; 翁宝凤; 胡玉龙

    2015-01-01

    从地理知觉、地理表象、地理概念化、地理知识的心理表征和地理空间推理的地理空间认知内容上,探索盲人地理空间认知的特点,提出了盲人电子地图的概念,并分析了盲人电子地图的特点。在此基础上,模拟盲人心象地图,进行内容选取、符号设计,并基于现有电子地图进行化简实现并完成了盲人电子地图,为盲人导航提供有力的基础工具。%From the geographical spatial cognition content,including geo-perception,geo-mental imagery,geo-conceptualization,mental representation of geographic Knowledge and geo-spatial reasoning,the characteristics of the blind of geographical spatial cognition were summarized,and the concept of the blind e-map was proposed. Then the further research was done to analysis the feature of blind e-map. On this basis,the simulation of blind mental map, content selection,symbol design,and simplification based on the existing electronic map were completed. Ultimate-ly,the blind e-map which provided a powerful tool for blind navigation was designed and fabricated.

  7. Imagery limitations in totally congenitally blind subjects.

    Science.gov (United States)

    De Beni, R; Cornoldi, C

    1988-10-01

    Research on totally blind subjects performing tasks that involve visual imagery has often shown that they do not behave differently from matched sighted subjects, even when their blindness is congenital. If visual imagery is based on visual perception, such tasks may not required visual imagery. In the present article visual images are considered as representations maintaining some properties of visible objects and constructed on the basis of information from various sources. Owing to the absence of visual experience, the limitations of such representations are explored in a series of experiments requiring memorization of single nouns, pairs of nouns, or triplets of nouns associated with a cue noun. Recall by blind subjects was impaired when multiple interactive images (with noun pairs and triplets) are formed. The poorer recall of blind subjects reflected also loss of order information. Recall was better for both groups with locative noun cues and high-imagery targets.

  8. Enhanced heat discrimination in congenital blindness

    DEFF Research Database (Denmark)

    Slimani, Hocine; Ptito, Maurice; Kupers, Ron

    2015-01-01

    There is substantial evidence that congenitally blind individuals perform better than normally sighted controls in a variety of auditory, tactile and olfactory discrimination tasks. However, little is known about the capacity of blind individuals to make fine discriminatory judgments in the thermal...... discrimination. Thermal stimuli were delivered with either a 2.56 or 9 cm(2) Peltier-based thermode. We applied for 5-8s lasting non-painful thermal stimuli to the forearm and asked participants to detect small increments in temperature (ΔT = 0.4, 0.8, 1.2 or 1.6°C) that occurred at random time intervals. Blank...... 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...

  9. Comparative analysis of two different alar base sutures after Le Fort I osteotomy: randomized double-blind controlled trial.

    Science.gov (United States)

    Ritto, Fabio G; Medeiros, Paulo José; de Moraes, Márcio; Ribeiro, Danilo Passeado Branco

    2011-02-01

    The aim of this prospective study was to analyze the efficacy of a new alar base cinch suture by comparing it with the commonly used cinch suture described by Schendel and Delaire in Dr. William Bell's book. Thirty-five patients submitted to maxillary impaction and/or advancements of ≥ 3 mm were randomly divided into 2 groups. Group 1 received an extra oral alar base cinch suture, and patients from group 2 received the classic intraoral suture. Alar and alar base width were measured before and after surgery in digital photographs, with the patient's head in a submental oblique view. Data were reported as means and standard deviations, and difference between groups were determined using Welch t test. A P value of alar base widening was 1.38 mm in group 1 and 2.5 mm in group 2, and mean alar widening was 1.40 mm in group 1 and 2.31 mm in group 2. The difference was statistically significant (P alar base cinch suture was more effective in maintaining preoperative Alar and alar base width compared with classic intraoral nasal suture. Copyright © 2011 Mosby, Inc. All rights reserved.

  10. Response of high-rise and base-isolated buildings to a hypothetical mw 7.0 blind thrust earthquake.

    Science.gov (United States)

    Heaton, T H; Hall, J F; Wald, D J; Halling, M W

    1995-01-13

    High-rise flexible-frame buildings are commonly considered to be resistant to shaking from the largest earthquakes. In addition, base isolation has become increasingly popular for critical buildings that should still function after an earthquake. How will these two types of buildings perform if a large earthquake occurs beneath a metropolitan area? To answer this question, we simulated the near-source ground motions of a M(w) 7.0 thrust earthquake and then mathematically modeled the response of a 20-story steel-frame building and a 3-story base-isolated building. The synthesized ground motions were characterized by large displacement pulses (up to 2 meters) and large ground velocities. These ground motions caused large deformation and possible collapse of the frame building, and they required exceptional measures in the design of the base-isolated building if it was to remain functional.

  11. [Double-blind peer review].

    Science.gov (United States)

    Fenyvesi, Tamás

    2002-02-03

    The peer review process in medical sciences is much debated. The method is not yet evidence based. Who are the reviewers and how do they perform? They are "independent" experts. As such they are bound to be involved in research similar to that outlined in the manuscript. Very often they are contestant in the same race. That is why the author consider the double blind method, where the author is blinded and the reviewer masked from each other's identity, the best choice. Nevertheless in very many scientific journals of high quality and envied impact factors do not blind the identity of the authors. Science is a race for fame, self accomplishment and also a means to get grants for pursuing the scientific research. Only success is able to provide resources for expensive scientific research. There is no fail-safe method against bias in grant giving and editorial process. In the tidal wave of electronic information it is mandatory to help in differentiating between signal and noise in science. Peer review is the best method to protect readers from the trash of uncontrolled publications in medical science.

  12. 基于噪声检测的置换混叠图像盲分离%Blind Separation for Permuted Alias Image Based on Noise Detection

    Institute of Scientific and Technical Information of China (English)

    段新涛; 方勇

    2011-01-01

    Permuted alias image is a new type of single channel blind separation, which is fundamentally different from traditional single channel blind separation in theory and method. In this paper, an algorithm about permuted alias image blind separation based noise detection is proposed according to a class of permuted alias image infecting noise in permuting region. Firstly a mathematical model of permuted alias image is presented. Then a dictionary about sparse representation is obtained by training samples from permuted alias image with K-SVD dictionary learning algorithm restrained by nonzeros number. The permuted alias image is denoised by utilizing learned dictionary. Size and location of permuting region is found out by detecting the subtraction image, which is defined as difference between the denoised permuted alias image and original permuted alias image. The permuting region is optimized by implementing image morphological operation and is separated from the permuted alias image by setting threshold. The results show that permuting image can be separated efficiently from the permuted alias image, not affected by size, location, number of permuting image and noise level on permuting image.%置换混叠图像盲分离作为一类新型的单信道盲分离,在理论和方法上与传统的单信道盲分离有着本质的不同.针对一类置换区域含噪声的置换混叠图像,本文提出一种基于噪声检测的置换混叠图像盲分离算法.本文首先给出置换混叠图像的数学模型,对置换混叠图像用非零元个数约束的K-SVD算法进行训练得到其稀疏表示的字典,利用学习得到的字典对置换混叠图像去噪,然后利用去噪后的置换混叠图像与原图像作差运算得到差图像,通过检测差图像来确定出置换区域的位置和大小.并利用图像形态学运算优化置换区域,采用阈值化操作分离出置换图像.实验结果表明,本文算法能够较好的从置换混叠图像中

  13. Prospective, double-blinded, randomised controlled trial assessing the effect of an Octenidine-based hydrogel on bacterial colonisation and epithelialization of skin graft wounds in burn patients.

    Science.gov (United States)

    W, Eisenbeiß; F, Siemers; G, Amtsberg; P, Hinz; B, Hartmann; T, Kohlmann; A, Ekkernkamp; U, Albrecht; O, Assadian; A, Kramer

    2012-01-01

    Moist wound treatment improves healing of skin graft donor site wounds. Microbial colonised wounds represent an increased risk of wound infection; while antimicrobially active, topical antiseptics may impair epithelialization. The aim of this prospective randomised controlled clinical trial was to examine the influence of an Octenidine-dihydrochloride (OCT) hydrogel on bacterial colonisation and epithelialization of skin graft donor sites. The study was designed as a randomised, double-blinded, controlled clinical trial. Skin graft donor sites from a total of 61 patients were covered either with 0.05% OCT (n=31) or an OCT-free placebo wound hydrogel (n=30). Potential interaction with wound healing was assessed by measuring the time until 100% re-epithelialization. In addition, microbial wound colonisation was quantitatively determined in all skin graft donor sites. There was no statistically significant difference in the time for complete epithelialization of skin graft donor sites in the OCT and the placebo group (7.3±0.2 vs. 6.9±0.2 days; p=0.236). Microbial wound colonisation was significantly lower in the OCT group than in the placebo group (p=0.014). The OCT-based hydrogel showed no delay in wound epithelialization and demonstrated a significantly lower bacterial colonisation of skin graft donor site wounds.

  14. Application of Blind Signature Based on CPK in Electronic Voting%基于CPK的盲签名在电子投票中的应用

    Institute of Scientific and Technical Information of China (English)

    刘涤

    2015-01-01

    With the wide use of computers and networks, human beings have entered the information age. People in work, study, life has realized the computer and network bringing convenience. Many of the traditional learning, life mode has gradually changed from the network and computer. For example, electronic voting has begun to be widely used, it overcomes the shortcomings of the traditional voting of human and material resources, giving people a new way to vote. Discusses the application of a blind signature scheme in the electronic voting based on the combined public key cryptography.%随着计算机和网络的广泛使用,人类进入了信息化时代. 人们在工作、学习、生活中已经体会到计算机和网络带来的便利和快捷. 很多传统的学习、生活模式已经逐渐由网络和计算机改变. 例如电子投票已经开始广泛使用,它克服传统投票的耗费人力、物力的缺点,给人们一种新的投票方式体验.探讨一种基于组合公钥密码技术的盲签名在电子投票中的应用.

  15. Therapeutic Efficacy of Fuzheng-Huayu Tablet Based Traditional Chinese Medicine Syndrome Differentiation on Hepatitis-B-Caused Cirrhosis: A Multicenter Double-Blind Randomized Controlled Trail

    Directory of Open Access Journals (Sweden)

    Ya-Nan Song

    2013-01-01

    Full Text Available Aim. To evaluate and predict the therapeutic efficacy of Fuzheng-Huayu tablet (FZHY based traditional Chinese Medicine (TCM syndrome differentiation or TCM symptoms on chronic hepatitis B caused cirrhosis (HBC. Methods. The trial was designed according to CONSORT statement. It was a multi-center, double-blind, randomized, placebo-controlled trail. Several clinical parameters, Child-Pugh classification and TCM symptoms were detected and evaluated. The FZHY efficacy was predicted by an established Bayes forecasting method following the Bayes classification model. Results. The levels of HA and TCM syndrome score in FZHY group were significantly decreased (P<0.05 compared to placebo group, respectively. The efficacy of FZHY on TCM syndrome score in HBC patients with some TCM syndromes was better. In TCM syndrome score evaluation, there were 53 effective and 22 invalid in FZHY group. TCM symptoms predicted FZHY efficacy on HBC were close to Child-Pugh score prediction. Conclusion. FZHY decreases the levels of HA and TCM syndrome scores, improves the life quality of HBC patients. Moreover, there were different therapeutic efficacies among different TCM syndromes, indicating that accurate TCM syndrome differentiation might guide the better TCM treatment. Furthermore, the FZHY efficacy was able to predict by Bayes forecasting method through the alteration of TCM symptoms.

  16. Anti-Stress, Behavioural and Magnetoencephalography Effects of an L-Theanine-Based Nutrient Drink: A Randomised, Double-Blind, Placebo-Controlled, Crossover Trial.

    Science.gov (United States)

    White, David J; de Klerk, Suzanne; Woods, William; Gondalia, Shakuntla; Noonan, Chris; Scholey, Andrew B

    2016-01-19

    L-theanine (γ-glutamylethylamide) is an amino acid found primarily in the green tea plant. This study explored the effects of an L-theanine-based nutrient drink on mood responses to a cognitive stressor. Additional measures included an assessment of cognitive performance and resting state alpha oscillatory activity using magnetoencephalography (MEG). Thirty-four healthy adults aged 18-40 participated in this double-blind, placebo-controlled, balanced crossover study. The primary outcome measure, subjective stress response to a multitasking cognitive stressor, was significantly reduced one hour after administration of the L-theanine drink when compared to placebo. The salivary cortisol response to the stressor was reduced three hours post-dose following active treatment. No treatment-related cognitive performance changes were observed. Resting state alpha oscillatory activity was significantly greater in posterior MEG sensors after active treatment compared to placebo two hours post-dose; however, this effect was only apparent for those higher in trait anxiety. This change in resting state alpha oscillatory activity was not correlated with the change in subjective stress response or the cortisol response, suggesting further research is required to assess the functional relevance of these treatment-related changes in resting alpha activity. These findings further support the anti-stress effects of L-theanine.

  17. Efficacy and tolerability of a polysaccharide-resin-honey based cough syrup as compared to carbocysteine syrup for children with colds: a randomized, single-blinded, multicenter study.

    Science.gov (United States)

    Cohen, Herman Avner; Hoshen, Moshe; Gur, Shmuel; Bahir, Arie; Laks, Yoseph; Blau, Hannah

    2017-02-01

    Available pediatric treatments for acute cough are limited by lack of demonstrated efficacy. The objective of this trial is to compare the effects of a polysaccharide-resin-honey based cough syrup, and carbocysteine syrups on nocturnal and daytime cough associated with childhood upper respiratory tract infections (URIs). Using a single-blind randomization design, the study recruited children from 4 general pediatric community clinics. Participants included 150 children aged 2 to 5 years with an URI, nocturnal and daytime cough and illness duration of ≤7 days. To be eligible, children had to be free of medication on the day before presentation. A survey was administered to parents on 4 consecutive days beginning from the day of presentation in clinic. Children received the study preparation on the first evening and then 3 times per day for 3 further days. Main outcome measures were cough frequency, cough severity, bothersome nature of cough, and quality of sleep for both child and parent. Both preparations were well tolerated and cough improved over the study period. After one night and on all survey days, there was a significantly better result for polysaccharide-resin-honey (Pcarbocysteine cough syrups were well tolerated in children over 2 years of age. The polysaccharide-resin-honey syrup was associated with a more rapid and greater improvement in all clinical cough symptoms measured, beginning from the first night of therapy. Both nocturnal and daytime cough improved, as did sleep quality for both children and parents.

  18. Clinical double-blind trial on the dermal tolerance and user acceptability of six alcohol-based hand disinfectants for hygienic hand disinfection.

    Science.gov (United States)

    Kramer, A; Bernig, T; Kampf, G

    2002-06-01

    Six commercially available alcohol-based hand rubs [AHD 2000, Desderman, Mucasept A, Manorapid (Poly-Alkohol, Spitacid, and Sterillium] were investigated in a clinical double-blind trial involving 10 participants who had no previous experience of using hand rubs (Group 1), and seven who had substantial professional experience of using hand rubs (Group 2; virology laboratory staff). Group 1 was studied for one week with 20 applications on day 1 and then five applications per day for six days. Transepidermal water loss, dermal water content and superficial sebum content of the skin were measured before and after the seven-day application of the products, as well as user acceptability (self-assessment of smell, speed of drying, emolliant effect, skin dryness). Group 2 used each preparation twice for two weeks in a random sequence, and carried out self assessment at the end of each fortnight. Transepidermal water loss (mean baseline: 18.7 g/m(2)h), dermal water content (mean baseline dorsum: 75.6) and superficial sebum content (mean baseline dorsum: 4.8 microg/cm(2)) did not change significantly. In both groups assessments of the smell and the speed of drying did not reveal any significant differences between the six products. Sterillium had the best emollient effect of all products (PSterillium is the only hand disinfectant containing mecetronium etilsulphate which has been shown to have an emolliant effect. Future research should focus on user acceptability in order to improve compliance.

  19. Anti-Stress, Behavioural and Magnetoencephalography Effects of an l-Theanine-Based Nutrient Drink: A Randomised, Double-Blind, Placebo-Controlled, Crossover Trial

    Directory of Open Access Journals (Sweden)

    David J. White

    2016-01-01

    Full Text Available l-theanine (γ-glutamylethylamide is an amino acid found primarily in the green tea plant. This study explored the effects of an l-theanine-based nutrient drink on mood responses to a cognitive stressor. Additional measures included an assessment of cognitive performance and resting state alpha oscillatory activity using magnetoencephalography (MEG. Thirty-four healthy adults aged 18–40 participated in this double-blind, placebo-controlled, balanced crossover study. The primary outcome measure, subjective stress response to a multitasking cognitive stressor, was significantly reduced one hour after administration of the l-theanine drink when compared to placebo. The salivary cortisol response to the stressor was reduced three hours post-dose following active treatment. No treatment-related cognitive performance changes were observed. Resting state alpha oscillatory activity was significantly greater in posterior MEG sensors after active treatment compared to placebo two hours post-dose; however, this effect was only apparent for those higher in trait anxiety. This change in resting state alpha oscillatory activity was not correlated with the change in subjective stress response or the cortisol response, suggesting further research is required to assess the functional relevance of these treatment-related changes in resting alpha activity. These findings further support the anti-stress effects of l-theanine.

  20. Growth of healthy term infants fed partially hydrolyzed whey-based infant formula: a randomized, blinded, controlled trial.

    Science.gov (United States)

    Borschel, Marlene W; Choe, Yong S; Kajzer, Janice A

    2014-12-01

    Partially hydrolyzed formulas (pHF) represent a significant percentage of the infant formula market. A new whey-based, palm olein oil (PO)-free pHF was developed and a masked, randomized, parallel growth study was conducted in infants fed this formula or a commercially available whey-based pHF with PO. Infants between 0 and 8 days were to be enrolled and studied to 119 days of age. Growth and tolerance of infants were evaluated. Mean weight gain from 14 to 119 days of age was similar between groups. There were no significant differences between groups in weight, length, head circumference (HC), or length or HC gains. Infants fed the new PO-free pHF had significantly softer stools than those fed the PO-containing formula except at 119 days of age. This study demonstrates that whereas growth of infants fed different formulas during the first 4 months of life may be similar, infants may tolerate individual formulas differently.

  1. A Robust and Non-Blind Watermarking Scheme for Gray Scale Images Based on the Discrete Wavelet Transform Domain

    Science.gov (United States)

    Bakhouche, A.; Doghmane, N.

    2008-06-01

    In this paper, a new adaptive watermarking algorithm is proposed for still image based on the wavelet transform. The two major applications for watermarking are protecting copyrights and authenticating photographs. Our robust watermarking [3] [22] is used for copyright protection owners. The main reason for protecting copyrights is to prevent image piracy when the provider distributes the image on the Internet. Embed watermark in low frequency band is most resistant to JPEG compression, blurring, adding Gaussian noise, rescaling, rotation, cropping and sharpening but embedding in high frequency is most resistant to histogram equalization, intensity adjustment and gamma correction. In this paper, we extend the idea to embed the same watermark in two bands (LL and HH bands or LH and HL bands) at the second level of Discrete Wavelet Transform (DWT) decomposition. Our generalization includes all the four bands (LL, HL, LH, and HH) by modifying coefficients of the all four bands in order to compromise between acceptable imperceptibility level and attacks' resistance.

  2. Demonstration of solar-blind Al{sub x}Ga{sub 1−x}N-based heterojunction phototransistors

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Lingxia; Tang, Shaoji; Liu, Changshan; Li, Bin; Wu, Hualong; Wang, Hailong [School of Physics and Engineering, Sun Yat-sen University, Guangzhou 510275 (China); Wu, Zhisheng [State Key Laboratory of Optoelectronic Materials and Technologies, Sun Yat-sen University, Guangzhou 510275 (China); Jiang, Hao, E-mail: stsjiang@mail.sysu.edu.cn [State Key Laboratory of Optoelectronic Materials and Technologies, Sun Yat-sen University, Guangzhou 510275 (China); School of Microelectronics, Sun Yat-sen University, Guangzhou 510275 (China)

    2015-12-07

    Al{sub 0.4}Ga{sub 0.6}N/Al{sub 0.65}Ga{sub 0.35}N heterojunction phototransistors have been fabricated from the epi-structure grown by low-pressure metal organic chemical vapor deposition on c-plane sapphire substrates. P-type conductivity of the AlGaN base layer was realized by using indium surfactant-assisted Mg-delta doping method. Regrowth technique was used to suppress the Mg memory effect on the n-type emitter. The fabricated devices with a 150-μm-diameter active area exhibited a bandpass spectral response between 235 and 285 nm. Dark current was measured to be less than 10 pA for bias voltages below 2.0 V. A high optical gain of 1.9 × 10{sup 3} was obtained at 6 V bias.

  3. Internet-based treatment for older adults with depression and co-morbid cardiovascular disease: protocol for a randomised, double-blind, placebo controlled trial

    Directory of Open Access Journals (Sweden)

    Christensen Helen

    2011-01-01

    Full Text Available Abstract Background Depression, cardiovascular disease (CVD risk factors and cognitive impairment are important causes of disability and poor health outcomes. In combination they lead to an even worse prognosis. Internet or web-based interventions have been shown to deliver efficacious psychological intervention programs for depression on a large scale, yet no published studies have evaluated their impact among patients with co-existing physical conditions. The aims of this randomised controlled trial are to determine the effects of an evidence-based internet intervention program for depression on depressive mood symptoms, cognitive function and treatment adherence in patients at risk of CVD. Methods/Design This study is an internet-based, double-blind, parallel group randomised controlled trial. The trial will compare the effectiveness of online cognitive behavioural therapy with an online attention control placebo. The trial will consist of a 12-week intervention phase with a 40-week follow-up. It will be conducted in urban and rural New South Wales, Australia and will recruit a community-based sample of adults aged 45 to 75 years. Recruitment, intervention, cognitive testing and follow-up data collection will all be internet-based and automated. The primary outcome is a change in severity of depressive symptoms from baseline to three-months. Secondary outcomes are changes in cognitive function and adherence to treatment for CVD from baseline to three, six and 12-months. Discussion Prior studies of depression amongst patients with CVD have targeted those with previous vascular events and major depression. The potential for intervening earlier in these disease states appears to have significant potential and has yet to be tested. Scalable psychological programs using web-based interventions could deliver care to large numbers in a cost effective way if efficacy were proved. This study will determine the effects of a web-based intervention on

  4. 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...

  5. Understanding and Creating Accessible Touch Screen Interactions for Blind People

    Science.gov (United States)

    Kane, Shaun K.

    2011-01-01

    Using touch screens presents a number of usability and accessibility challenges for blind people. Most touch screen-based user interfaces are optimized for visual interaction, and are therefore difficult or impossible to use without vision. This dissertation presents an approach to redesigning gesture-based user interfaces to enable blind people…

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

    Science.gov (United States)

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

    2017-05-01

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

  8. Nonlinear Blind Equalization for Volume Holographic Data Storage

    Institute of Scientific and Technical Information of China (English)

    商未雄; 何庆声; 金国藩

    2004-01-01

    We investigate the nonlinear blind equalization for volume holographic data storage channel. Base on the recurrent neural network channel model, we describe a novel blind equalizer for the volume holographic data storage system to improve the bit error rate and hence to make the storage densities achievable. The experimental results also indicate that a significant improvement in the bit error rate to 2.55 × 10-3 is possible with the nonlinear blind equalization.

  9. 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.

  10. 基于身份的一次性盲公钥方案%One-off Blind Public Key Scheme Based on Identity

    Institute of Scientific and Technical Information of China (English)

    赵伟艇; 申远

    2012-01-01

    在现有方案的基础上,通过分析超椭圆曲线双线性对和基于身份的特点,给出了一个改进的基于身份的一次性盲公钥方案.该方案由用户和可信中心共同完成用户密钥的生成,克服了密钥托管问题,避免了由可信中心进行密钥管理所产生的安全隐患.新构造的方案能够抵抗伪造性攻击,具有不可欺骗性,又保证了一次性盲公钥的独立性,是安全可靠的.而且方案中用户在通讯时可以使用不同的公钥,解决了Internet通信中的匿名认证问题,实现了用户隐私的有效保护.%By analyzing the characteristic of the bilinear pairings on hyper-elliptic curves and identity-based cryptography, an improved one-off blind public key scheme based on the existing schemes is proposed. The scheme solves the problem of the key escrow by users and trust center generated encryption key, so it avoids security problems caused by single independent key management. The scheme is robust a-gainst the Forgery attack and ensures the independence of user's public key. This scheme is satisfied. And user's public key is different ever-y time, it can be applied to implementing internet anonymous attestation for privacy protection.

  11. GLP-1-Based Therapies Have No Microvascular Effects in Type 2 Diabetes Mellitus: An Acute and 12-Week Randomized, Double-Blind, Placebo-Controlled Trial.

    Science.gov (United States)

    Smits, Mark M; Tonneijck, Lennart; Muskiet, Marcel H A; Hoekstra, Trynke; Kramer, Mark H H; Diamant, Michaela; Serné, Erik H; van Raalte, Daniël H

    2016-10-01

    To assess the effects of glucagon-like peptide (GLP)-1-based therapies (ie, GLP-1 receptor agonists and dipeptidyl peptidase-4 inhibitors) on microvascular function in patients with type 2 diabetes mellitus. We studied 57 patients with type 2 diabetes mellitus (mean±SD age: 62.8±6.9 years; body mass index: 31.8±4.1 kg/m(2); HbA1c [glycated hemoglobin] 7.3±0.6%) in an acute and 12-week randomized, placebo-controlled, double-blind trial conducted at the Diabetes Center of the VU University Medical Center. In the acute study, the GLP-1 receptor agonist exenatide (therapeutic concentrations) or placebo (saline 0.9%) was administered intravenously. During the 12-week study, patients received the GLP-1 receptor agonist liraglutide (1.8 mg daily), the dipeptidyl peptidase-4 inhibitor sitagliptin (100 mg daily), or matching placebos. Capillary perfusion was assessed by nailfold skin capillary videomicroscopy and vasomotion by laser Doppler fluxmetry, in the fasting state and after a high-fat mixed meal. In neither study, treatment affected fasting or postprandial capillary perfusion compared with placebo (P>0.05). In the fasting state, acute exenatide infusion increased neurogenic vasomotion domain power, while reducing myogenic domain power (both Pdiabetes mellitus. Twelve-week treatment with liraglutide or sitagliptin has no effect on capillary perfusion or vasomotion in these patients. Our data suggest that the effects of GLP-1-based therapies on glucose are not mediated through microvascular responses. © 2016 American Heart Association, Inc.

  12. Social attitudes and beliefs of sighted people towards blindness and blind persons

    Directory of Open Access Journals (Sweden)

    Papadaki Maria

    2013-01-01

    Full Text Available Blindness has been interpreted in different, often controversial ways, since ancient times. It has been stereotyped and labeled by sighted people and has thus affected the acceptance of Visually Impaired persons, the tolerance towards them and their integration into societal life. The main purpose of this study is to find out the contemporary beliefs and social attitudes of Greek sighted people towards blindness and blind persons. 115 sighted Greek people, most of them from urban and rural areas of Athens and Crete, were asked to fill in a questionnaire consisting of 25 questions. Our results showed that firstly, visually impaired people are still treated with some prejudice concerning the size of their disability, their education and their integration into society. However, they have ceased to apply antiquated perceptions based on fear or ignorance. Sighted people no longer believe that blind individuals are beggars, evil or blinded because of a punishment. Secondly, sighted people still believe that blind persons possess some extra powers and abilities such as better sense of things, especially of hearing, sixth sense or better judgment abilities. Finally, the common belief about associating blind people with their musical talents and skills is no longer in actual existence.

  13. 基于线性预测方法的水声信道最小均方误差盲均衡%Blind Adaptive MMSE Equalization of Underwater Acoustic Channels Based on the Linear Prediction Method

    Institute of Scientific and Technical Information of China (English)

    张银兵; 赵俊渭; 郭业才; 李金明

    2011-01-01

    The problem of blind adaptive equalization of underwater single-input multiple-output (SIMO)acoustic channels was analyzed by using the linear prediction method. Minimum mean square error (MMSE)blind equalizers with arbitrary delay were described on a basis of channel identification. Two methods for calculating linear MMSE equalizers were proposed. One was based on full channel identification and realized using RLS adaptive algorithms, and the other was based on the zero-delay MMSE equalizer and realized using LMS and RLS adaptive algorithms, respectively. Performance of the three proposed algorithms and comparison with two existing zero-forcing (ZF) equalization algorithms were investigated by simulations utilizing two underwater acoustic channels. The results show that the proposed algorithms are robust enough to channel order mismatch. They have almost the same performance as the corresponding ZF algorithms under a high signal-to-noise (SNR) ratio and better performance under a low SNR.

  14. 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...

  15. 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...

  16. Testing Children for Color Blindness

    Science.gov (United States)

    ... Stories Español Eye Health / News Testing Children for Color Blindness Written By: Shirley Dang Apr. 03, 2014 New study shows that kids can be tested for color blindness as soon as age 4, finds Caucasian boys ...

  17. 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.

  18. PARENT Quick Blind Round-Robin Test Report

    Energy Technology Data Exchange (ETDEWEB)

    Braatz, Brett G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Heasler, Patrick G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Meyer, Ryan M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2014-09-30

    The U.S. Nuclear Regulatory Commission has established the Program to Assess the Reliability of Emerging Nondestructive Techniques (PARENT) whose goal is to investigate the effectiveness of current and novel nondestructive examination procedures and techniques to find flaws in nickel-alloy welds and base materials. This is to be done by conducting a series of open and blind international round-robin tests on a set of piping components that include large-bore dissimilar metal welds, small-bore dissimilar metal welds, and bottom-mounted instrumentation penetration welds. The blind testing is being conducted in two segments, one is called Quick-Blind and the other is called Blind. The Quick-Blind testing and destructive analysis of the test blocks has been completed. This report describes the four Quick-Blind test blocks used, summarizes their destructive analysis, gives an overview of the nondestructive evaluation (NDE) techniques applied, provides an analysis inspection data, and presents the conclusions drawn.

  19. Immunogenicity and safety of a cell culture-based quadrivalent influenza vaccine in adults: A Phase III, double-blind, multicenter, randomized, non-inferiority study

    Science.gov (United States)

    Bart, Stephan; Cannon, Kevin; Herrington, Darrell; Mills, Richard; Forleo-Neto, Eduardo; Lindert, Kelly; Abdul Mateen, Ahmed

    2016-01-01

    ABSTRACT Quadrivalent influenza vaccines (QIVs), which include both B lineage strains, are expected to provide broader protection than trivalent influenza vaccines (TIVs). The non-inferiority, immunogenicity, and safety of a cell culture-based investigational QIVc and 2 TIVs (TIV1c, TIV2c), in adults (≥18 y), were evaluated in this Phase III, double-blind, multicenter study. A total of 2680 age-stratified subjects were randomized (2:1:1) to receive 1 dose of QIVc (n = 1335), TIV1c (n = 676), or TIV2c (n = 669). TIV1c (B/Yamagata) and TIV2c (B/Victoria) differed only in B strain lineage. The primary objective was to demonstrate non-inferiority of the hemagglutinin-inhibition antibody responses of QIVc against TIVc, 22 d post-vaccination. Secondary objectives included the evaluation of immunogenicity of QIVc and TIVc in younger (≥18 – <65 y) and older (≥65 y) adults. Hemagglutinin inhibition assays were performed at days 1 and 22. Solicited local and systemic adverse events (AEs) were monitored for 7 d post-vaccination, and unsolicited AEs and serious AEs until day 181. QIVc met the non-inferiority criteria for all 4 vaccine strains and demonstrated superiority for both influenza B strains over the unmatched B strain included in the TIV1c and TIV2c, when geometric mean titers and seroconversion rates with TIVc were compared at day 22. Between 48%–52% of subjects experienced ≥1 solicited AE, the most common being injection-site pain and headache. Serious AEs were reported by ≤1% of subjects, none were vaccine-related. The results indicate that QIVc is immunogenic and well tolerated in both younger and older adults. The immunogenicity and safety profiles of QIVc and TIVc were comparable at all ages evaluated. PMID:27322354

  20. A single-blind randomised controlled trial of the effects of a web-based decision aid on self-testing for cholesterol and diabetes. Study protocol.

    Science.gov (United States)

    Ickenroth, Martine H P; Grispen, Janaica E J; de Vries, Nanne K; Dinant, Geert-Jan; Elwyn, Glyn; Ronda, Gaby; van der Weijden, Trudy

    2012-01-04

    Self-tests, tests on body materials to detect medical conditions, are widely available to the general public. Self-testing does have advantages as well as disadvantages, and the debate on whether self-testing should be encouraged or rather discouraged is still ongoing. One of the concerns is whether consumers have sufficient knowledge to perform the test and interpret the results. An online decision aid (DA) with information on self-testing in general, and test specific information on cholesterol and diabetes self-testing was developed. The DA aims to provide objective information on these self-tests as well as a decision support tool to weigh the pros and cons of self-testing. The aim of this study is to evaluate the effect of the online decision aid on knowledge on self-testing, informed choice, ambivalence and psychosocial determinants. A single blind randomised controlled trial in which the online decision aid 'zelftestwijzer' is compared to short, non-interactive information on self-testing in general. The entire trial will be conducted online. Participants will be selected from an existing Internet panel. Consumers who are considering doing a cholesterol or diabetes self-test in the future will be included. Outcome measures will be assessed directly after participants have viewed either the DA or the control condition. Weblog files will be used to record participants' use of the decision aid. Self-testing does have important pros and cons, and it is important that consumers base their decision whether they want to do a self-test or not on knowledge and personal values. This study is the first to evaluate the effect of an online decision aid for self-testing. Dutch Trial Register: NTR3149.

  1. Blind Watermarking Algorithm Based on Quaternion for Double Color Image%基于四元数的双彩色图像盲水印算法

    Institute of Scientific and Technical Information of China (English)

    姚涛; 苏庆堂; 阙大顺

    2013-01-01

    提出一种基于四元数的双彩色图像盲水印算法.对载体图像和水印图像分别进行离散四元数傅里叶变换后,对水印图像频域的低频、中频和高频系数做混沌置乱处理,并利用脉冲编码调制方法,在载体图像的低频、中频和高频嵌入置乱后水印的相应频带系数,通过逆离散四元数傅里叶变换得到嵌入水印的图像.实验结果表明,该算法保证水印具有较高的透明性,对剪切、叠加噪声、JPEG压缩等常见的攻击具有较好的鲁棒性.%This paper proposes a blind watermarking algorithm for double color image based on quaternion. Frequency matirx of the host image and watermark image are gained by using quaternion Fourier transform, and low frequency, middle frequency and high frequency are scrambled by the chaotic sequences. The scrambled watermark is embedded in low frequency, middle frequency and high frequency of host image by using Pulse Code Modulation(PCM). The watermarked host image are gained by using inverse Discrete Quaternion Fourier Transform(DQFT). Experimental results show that the algorithm has the property of perceptual transparency, and is robust to common image attacks, such as cropping image, noise, JPEG compression and so on.

  2. Characterization of AlGaN-based metal-semiconductor solar-blind UV photodiodes with IrO{sub 2} Schottky contacts

    Energy Technology Data Exchange (ETDEWEB)

    Schalkwyk, L. van, E-mail: Louwrens.VanSchalkwyk@up.ac.za [Department of Physics, University of Pretoria, Private bag X20, Hatfield 0028 (South Africa); Meyer, W.E.; Auret, F.D.; Nel, J.M.; Ngoepe, P.N.M.; Diale, M. [Department of Physics, University of Pretoria, Private bag X20, Hatfield 0028 (South Africa)

    2012-05-15

    Intrinsically solar-blind ultraviolet (UV) AlGaN-based Schottky photodiodes were fabricated using Iridium oxide (IrO{sub 2}) as the Schottky barrier material. The Ir Schottky contacts were annealed at 700 Degree-Sign C under O{sub 2} ambient and the photodiodes characterized with an optoelectronic system. The main parameters extracted from I-V measurements were an average ideality factor of 1.38, a Schottky barrier height of 1.52 eV, a reverse leakage current density at -1 V bias of 5.2 nA/cm{sup 2} and series resistance of 250{Omega}. After spectral characterization, it was found that annealing, alone, of the Ir contact to form the more UV transmissive IrO{sub 2} does not always improve the responsivity. The deposition of a Au probe contact on the IrO{sub 2} contact increased the responsivity from 40 mA/W to 52 mA/W at 275 nm with respect to the annealed Ir contact. However, the ideality factor degraded to 1.57, Schottky barrier height lowered to 1.19 eV, reverse leakage current density increased to 49 nA/cm{sup 2} and series resistance decreased to 100{Omega} with the addition of the Au contact. The radiation hardness of AlGaN was also confirmed after studying the effects of 5.4 MeV He-ion irradiation using {sup 241}Am for a total fluence of 3 Multiplication-Sign 10{sup 13} cm{sup -2}.

  3. 基于 CMOE 准则的盲自适应 RLS 检测器%Blind adaptive RLS detector based on CMOE criterion

    Institute of Scientific and Technical Information of China (English)

    李辉; 史朋; 高维廷

    2013-01-01

      针对直接递归最小二乘(RLS)算法存在的检测数值不稳定和收敛速度较慢等问题,将约束最小输出能量(CMOE)准则与直接 RLS 算法结合,提出一种基于 CMOE 准则的盲自适应 RLS 多用户检测算法。将该算法与直接 RLS 算法进行动、静态环境下输出信干比(SIR)、剩余输出能量(EOE)和误码率(BER)等方面的仿真,对比得出该算法具有更好的动态跟踪能力,更快的收敛速度和更高的稳定性。%A blind adaptive recursive least squares multiuser detection algorithm based on Constrained Minimum Output Energy (CMOE)criterion is proposed to cope with the numerical instability and slow convergence rate of normal Recursive Least Squares(RLS)algorithm. This algorithm is a combination of CMOE criterion and normal RLS algorithm. Detailed simulation is carried out to compare the proposed algorithm with the normal RLS algorithm in the aspects of Signal Interference Ratio(SIR), Excess Output Energy(EOE)and Bit Error Rate(BER)under conditions of both static and dynamic. Simulation results show that the algorithm is performed with more dynamic tracking ability, faster convergence speed and better stability.

  4. PCA与ICA相结合的语音信号盲分离%Blind separation for speech signal based on PCA and ICA

    Institute of Scientific and Technical Information of China (English)

    王玉静; 于凤芹

    2012-01-01

    针对ICA用于语音信号盲分离时,由于数据量过大、迭代次数过多引起的收敛速度慢的问题,采用一种PCA和ICA相结合的盲分离算法PCA-ICA.通过PCA对混合语音信号进行白化处理,消除了原始各道数据间的二阶相关性.在仿真实验中,采用相似系数矩阵作为评价混合语音信号分离效果的标准,结果表明PCA-ICA算法与ICA算法相比,在达到几乎相同的相似系数矩阵的情况下,迭代次数减少了90%,从而分离速度提高了3倍,有效地解决了ICA分离算法收敛速度慢的问题.%In order to solve the slow convergence problem of ICAbased algorithm and high computational cost due to excessive amount data, an blind separation algorithm based on PCA-ICA for speech signal is proposed. PCA is used to remove the second-ordfir correlations among different dimensions of feature from original data. Using similarity coefficient matrix as the separation effect standard, the simulation experiment results show that the proposed method can reduce 90% of iterations and is 3 times faster compared with ICA with the same separation accuracy. Thus the ICA-PCA algorithm effectively solves the slow convergence problem of original ICA method.

  5. Rationale and design of a community-based double-blind randomized clinical trial of an HPV 16 and 18 vaccine in Guanacaste, Costa Rica

    Science.gov (United States)

    Herrero, Rolando; Hildesheim, Allan; Rodríguez, Ana C; Wacholder, Sholom; Bratti, Concepción; Solomon, Diane; González, Paula; Porras, Carolina; Jiménez, Silvia; Guillen, Diego; Morales, Jorge; Alfaro, Mario; Cyr, Jean; Morrisey, Kerrygrace; Estrada, Yenory; Cortés, Bernal; Morera, Lidia Ana; Freer, Enrique; Schussler, John; Schiller, John; Lowy, Douglas; Schiffman, Mark

    2008-01-01

    We report the rationale, design, methods and details of participation of a community-based, double blind, randomized clinical trial of an HPV 16 and 18 vaccine conducted in two provinces of Costa Rica to investigate the efficacy and population impact of the vaccine in the prevention of cervical cancer precursors. More than 24,000 women between 18 and 25 years of age were invited to participate and pre-screened for eligibility, with recruitment of 7,466 women (30% of those prescreened, 59% of those eligible) who were randomized to receive 3 doses of the HPV vaccine or hepatitis A vaccine as control. A complex protocol of data and specimen collection was applied, including an interview, pelvic exam for sexually active women, blood for serology and cell-mediated immunity, cervical secretions for local immunity and cells for HPV, Chlamydia trachomatis and Gonorrhea testing. Eighty percent of the women received 3 doses, 12.4% two doses and 7.4% one dose. At visits, compliance with data and specimen collection was close to 100%. Baseline characteristics and age-specific prevalence of HPV and cervical neoplasia are reported. Overall prevalence of HPV was high (50%), with 8.3% of women having HPV 16 and 3.2% HPV 18. LSIL was detected in 12.7% of women at baseline and HSIL in 1.9%. Prevalence of Chlamydia was 14.2%. There was very good agreement in HPV detection between clinician-collected and self-collected specimens (89.4% agreement for all types, kappa 0.59). Follow up will continue with yearly or more frequent examinations for at least 4 years for each participant. PMID:18640170

  6. Blind Detection Algorithms for Forged Images Based on Artificial Neural Networks%基于人工神经网络的数字图像盲取证

    Institute of Scientific and Technical Information of China (English)

    高强; 张华熊

    2011-01-01

    数字图像盲取证技术是一项通过图像本身统计特性来鉴别图像是否被篡改的技术.文章基于数码相机的成像原理,利用人工神经网络来预测成像过程中由于CFA(color filter arrays)插值算法导致图像像素点之间出现的相关性关系,由于没有篡改的图像采用的CFA插值算法是相同的,而被篡改的图像则可能存在两种以上的CFA插值算法,两种情况下图像预测误差会出现差异,本算法利用这种差异实现数字图像的盲取证.实验结果表明本算法具有一定的有效性.%Blind detection algorithms for images is a technique which uses image itself statistical features to identify the forged images. In this paper the authors bring forward a new algorithms which is based on imaging principle of digital camera, using artificial neural networks to forecasting the relationship between the relevant pixel. The image which has not been forged has only one interpolated algorithms, but the forged one may have two or more, so if using artificial neural networks to forecast two types of these images we will get different results, by this difference can find forged image. The result of simulation implies that this calculation has some effects.

  7. A single-blind randomised controlled trial of the effects of a web-based decision aid on self-testing for cholesterol and diabetes. study protocol

    Directory of Open Access Journals (Sweden)

    Ickenroth Martine HP

    2012-01-01

    Full Text Available Abstract Background Self-tests, tests on body materials to detect medical conditions, are widely available to the general public. Self-testing does have advantages as well as disadvantages, and the debate on whether self-testing should be encouraged or rather discouraged is still ongoing. One of the concerns is whether consumers have sufficient knowledge to perform the test and interpret the results. An online decision aid (DA with information on self-testing in general, and test specific information on cholesterol and diabetes self-testing was developed. The DA aims to provide objective information on these self-tests as well as a decision support tool to weigh the pros and cons of self-testing. The aim of this study is to evaluate the effect of the online decision aid on knowledge on self-testing, informed choice, ambivalence and psychosocial determinants. Methods/Design A single blind randomised controlled trial in which the online decision aid 'zelftestwijzer' is compared to short, non-interactive information on self-testing in general. The entire trial will be conducted online. Participants will be selected from an existing Internet panel. Consumers who are considering doing a cholesterol or diabetes self-test in the future will be included. Outcome measures will be assessed directly after participants have viewed either the DA or the control condition. Weblog files will be used to record participants' use of the decision aid. Discussion Self-testing does have important pros and cons, and it is important that consumers base their decision whether they want to do a self-test or not on knowledge and personal values. This study is the first to evaluate the effect of an online decision aid for self-testing. Trial registration Dutch Trial Register: NTR3149

  8. Semi-blind Channel Estimator for OFDM-STC

    Institute of Scientific and Technical Information of China (English)

    WU Yun; LUO Han-wen; SONG Wen-tao; HUANG Jian-guo

    2007-01-01

    Channel state information of OFDM-STC system is required for maximum likelihood decoding. A subspace-based semi-blind method was proposed for estimating the channels of OFDM-STC systems. The channels are first estimated blindly up to an ambiguity parameter utilizing the nature structure of STC, irrespective of the underlying signal constellations. Furthermore, a method was proposed to resolve the ambiguity by using a few pilot symbols. The simulation results show the proposed semi-blind estimator can achieve higher spectral efficiency and provide improved estimation performance compared to the non-blind estimator.

  9. 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...

  10. An adaptive regression method for infrared blind-pixel compensation

    Science.gov (United States)

    Chen, Suting; Meng, Hao; Pei, Tao; Zhang, Yanyan

    2017-09-01

    Blind pixel compensation is an ill-posed inverse problem of infrared imaging systems and image restoration. The performance of a blind pixel compensation algorithm depends on the accuracy of estimation for the underlying true infrared images. We propose an adaptive regression method (ARM) for blind pixel compensation that integrates the multi-scale framework with a regression model. A blind-pixel is restored by exploiting the intra-scale properties through the nonparametric regressive estimation and the inter-scale characteristics via parametric regression for continuous learning. Combining the respective strengths of a parametric model and a nonparametric model, ARM establishes a set of multi-scale blind-pixel compensation method to correct the non-uniformity based on key frame extraction. Therefore, it is essentially different from the traditional frameworks for blind pixel compensation which are based on filtering and interpolation. Experimental results on some challenging cases of blind compensation show that the proposed algorithm outperforms existing methods by a significant margin in both isolated blind restoration and clustered blind restoration.

  11. Transition for Persons with Deaf-Blindness and Other Profound Handicaps: State of the Art. Section I. Community Based Residential Options.

    Science.gov (United States)

    Romer, Lyle T.; And Others

    This compilation brings together various conference papers and a working group report on the topic of residential services for people with deaf-blindness and other profound disabilities. The title paper by Lyle T. Romer describes three measures for evaluating residential programs: capacity, progress, and lifestyle. Valued outcomes of a residential…

  12. [The blindness in the literature-Jose Saramago: blindness and Albert Bang: the blind witness].

    Science.gov (United States)

    Permin, H; Norn, M

    2001-01-01

    Two novels with different aspects of blindness seen through the doctors eyes. The Portuguese Nobel-prize winner José Saramago's story of a city struck by an epidemic of "white blindness", where the truth is what we cannot bear to see. The Danish author and unskilled labourer Albert Bang's (synonym with Karl E. Rasmussen) crime novel describes a blind or pretend to be blind butcher, who is a witness to a murder. Both novels are lyric, thought-provoking and insightful.

  13. Validity of False Belief Tasks in Blind Children

    Science.gov (United States)

    Brambring, Michael; Asbrock, Doreen

    2010-01-01

    Previous studies have reported that congenitally blind children without any additional impairment reveal a developmental delay of at least 4 years in perspective taking based on testing first-order false-belief tasks. These authors interpret this delay as a sign of autism-like behavior. However, the delay may be caused by testing blind children…

  14. Unconditionally verifiable blind computation

    CERN Document Server

    Fitzsimons, Joseph F

    2012-01-01

    Blind Quantum Computing (BQC) allows a client to have a server carry out a quantum computation for them such that the client's input, output and computation remain private. Recently the authors together with Broadbent proposed a universal unconditionally secure BQC scheme where the client only needs to be able to prepare single qubits in separable states randomly chosen from a finite set and send them to the server, who has the balance of the required quantum computational resources. A desirable property for any BQC protocol is verification, whereby the client can verify with high probability whether the server has followed the instructions of the protocol, or if there has been some deviation resulting in a corrupted output state. A verifiable BQC protocol can be viewed as an interactive proof system leading to consequences for complexity theory. In this paper we extend the BQC protocol presented in [Broadbent, Fitzsimons and Kashefi, FOCS 2009 p517] with new functionality allowing blind computational basis m...

  15. Blind Quantum Computation

    CERN Document Server

    Arrighi, P; Arrighi, Pablo; Salvail, Louis

    2003-01-01

    We investigate the possibility of having someone carry out the work of executing a function for you, but without letting him learn anything about your input. Say Alice wants Bob to compute some well-known function f upon her input x, but wants to prevent Bob from learning anything about x. The situation arises for instance if client Alice has limited computational resources in comparison with mistrusted server Bob, or if x is an inherently mobile piece of data. Could there be a protocol whereby Bob is forced to compute f(x) "blindly", i.e. without observing x? We provide such a blind computation protocol for the class of functions which admit an efficient procedure to generate random input-output pairs, e.g. factorization. The setting is quantum, the security is unconditional, the eavesdropper is as malicious as can be. Keywords: Secure Circuit Evaluation, Secure Two-party Computation, Information Hiding, Information gain vs disturbance.

  16. JPEG BLIND STEGANALYSIS BASED ON FEATURE FUSION AND CLUSTERING%基于特征融合聚类的JPEG盲隐写分析

    Institute of Scientific and Technical Information of China (English)

    周楠; 赵险峰; 黄炜; 盛任农

    2013-01-01

    The prior knowledge for traditional steganalysis, such as steganography algorithms, embedding rates and sources of images, etc. , is difficult to be satisfied in practice. In the scenario of blind steganalysis that the above conditions are unknown, analysis using clustering can effectively distinguish between the actor who performs steganography and the others. We propose a method for fusion which is suitable for the selected features, and is to improve the accuracy of JPEG' s steganalysis via clustering. It fuses the principal components of the feature based on partially ordered Markov models with the feature based on calibration, and makes full use of complementarity between features as well as reduces the redundancy, identifies out of the guilty actor better and improves the accuracy of identifying actors who perform steganography. Experimental results show that by different steganography approaches and in different embedding rate conditions, using our scheme can obtain a general increase in the accuracy of JPEG steganalysis by about 2% compared to the existing methods, and get a highest accuracy up to 16%.%传统隐写分析所需的隐写算法、嵌入率和图像来源等先验知识在实用中很难满足,上述条件未知的盲隐写分析场景下,使用聚类分析方法可以有效区分隐写者与非隐写者.设计一种适合所选特征的融合方案,用以提高JPEG聚类隐写分析的准确率,将偏序Markov模型特征的主成分与校准特征融合,充分利用特征互补并降低冗余,可以在参与者中更好地识别出隐写者,从而提高识别准确率.实验结果表明,在不同隐写算法和嵌入率条件下,采用该方法比现有方法准确率平均提高约2%,最高提高约16%.

  17. Placebo-controlled, double-blind, randomized, prospective study of a glycerol-based emollient on eczematous skin in atopic dermatitis: biophysical and clinical evaluation.

    Science.gov (United States)

    Breternitz, M; Kowatzki, D; Langenauer, M; Elsner, P; Fluhr, J W

    2008-01-01

    Atopic dermatitis (AD) is a frequent, chronic inflammatory disease influenced by local, immunological, genetic and environmental factors. Important symptoms of AD are dry skin, intense pruritus and impaired epidermal barrier function. The therapeutic management of AD is difficult and needs individualized concepts. Moisturizing creams and emollients are useful and important treatment adjuncts for the daily skin care of patients with dry and inflamed skin, e.g. AD. Glycerol is known to increase stratum corneum (SC) hydration, improve epidermal barrier function and decrease clinical signs of inflammation. However, no controlled study on the efficacy of glycerol on barrier function and SC hydration in AD has been published. In the present study, a topical 20% glycerol preparation was compared with its vehicle in patients with AD. The aim of the present study was to evaluate the effect of a single emollient ingredient in AD within the full frame of a phase III drug study. 24 patients with AD were treated for 4 weeks twice daily with a glycerol-based emollient in a randomized, double-blind study. Transepidermal water loss, skin capacitance, erythema and skin surface pH were assessed with biophysical, non-invasive instruments. The SCORAD and a local severity score were evaluated. After a wash-out period of 2 weeks, these parameters were assessed in order to quantify the sustained effect of this treatment. SC hydration was significantly improved, and epidermal barrier function was restored under treatment with glycerol-containing cream compared to the glycerol-free placebo. No significant differences were detectable for erythema values, SCORAD and local severity between the glycerol-containing cream and placebo. However, an improvement over time was detectable in the assessed parameters in both groups indicating the importance of emollient treatment in AD. Glycerol-based emollients have a positive influence on the skin of patients with AD. They enhance the SC hydration

  18. Turning the tide of corneal blindness.

    Science.gov (United States)

    Oliva, Matthew S; Schottman, Tim; Gulati, Manoj

    2012-01-01

    Corneal diseases represent the second leading cause of blindness in most developing world countries. Worldwide, major investments in public health infrastructure and primary eye care services have built a strong foundation for preventing future corneal blindness. However, there are an estimated 4.9 million bilaterally corneal blind persons worldwide who could potentially have their sight restored through corneal transplantation. Traditionally, barriers to increased corneal transplantation have been daunting, with limited tissue availability and lack of trained corneal surgeons making widespread keratoplasty services cost prohibitive and logistically unfeasible. The ascendancy of cataract surgical rates and more robust eye care infrastructure of several Asian and African countries now provide a solid base from which to dramatically expand corneal transplantation rates. India emerges as a clear global priority as it has the world's largest corneal blind population and strong infrastructural readiness to rapidly scale its keratoplasty numbers. Technological modernization of the eye bank infrastructure must follow suit. Two key factors are the development of professional eye bank managers and the establishment of Hospital Cornea Recovery Programs. Recent adaptation of these modern eye banking models in India have led to corresponding high growth rates in the procurement of transplantable tissues, improved utilization rates, operating efficiency realization, and increased financial sustainability. The widespread adaptation of lamellar keratoplasty techniques also holds promise to improve corneal transplant success rates. The global ophthalmic community is now poised to scale up widespread access to corneal transplantation to meet the needs of the millions who are currently blind.

  19. Turning the tide of corneal blindness

    Directory of Open Access Journals (Sweden)

    Matthew S Oliva

    2012-01-01

    Full Text Available Corneal diseases represent the second leading cause of blindness in most developing world countries. Worldwide, major investments in public health infrastructure and primary eye care services have built a strong foundation for preventing future corneal blindness. However, there are an estimated 4.9 million bilaterally corneal blind persons worldwide who could potentially have their sight restored through corneal transplantation. Traditionally, barriers to increased corneal transplantation have been daunting, with limited tissue availability and lack of trained corneal surgeons making widespread keratoplasty services cost prohibitive and logistically unfeasible. The ascendancy of cataract surgical rates and more robust eye care infrastructure of several Asian and African countries now provide a solid base from which to dramatically expand corneal transplantation rates. India emerges as a clear global priority as it has the world′s largest corneal blind population and strong infrastructural readiness to rapidly scale its keratoplasty numbers. Technological modernization of the eye bank infrastructure must follow suit. Two key factors are the development of professional eye bank managers and the establishment of Hospital Cornea Recovery Programs. Recent adaptation of these modern eye banking models in India have led to corresponding high growth rates in the procurement of transplantable tissues, improved utilization rates, operating efficiency realization, and increased financial sustainability. The widespread adaptation of lamellar keratoplasty techniques also holds promise to improve corneal transplant success rates. The global ophthalmic community is now poised to scale up widespread access to corneal transplantation to meet the needs of the millions who are currently blind.

  20. Postpartum cortical blindness.

    Science.gov (United States)

    Faiz, Shakeel Ahmed

    2008-09-01

    A 30-years-old third gravida with previous normal pregnancies and an unremarkable prenatal course had an emergency lower segment caesarean section at a periphery hospital for failure of labour to progress. She developed bilateral cortical blindness immediately after recovery from anesthesia due to cerebral angiopathy shown by CT and MR scan as cortical infarct cerebral angiopathy, which is a rare complication of a normal pregnancy.

  1. Color Blind Affirmative Action

    OpenAIRE

    2003-01-01

    This paper presents a conceptual framework for understanding the consequences of the widespread adoption of race-neutral alternatives' to conventional racial affirmative action policies in college admissions. A simple model of applicant competition with endogenous effort is utilized to show that, in comparison to color-conscious affirmative action, these color-blind alternatives can significantly lower the efficiency of the student selection process in equilibrium. We examine data on matricul...

  2. The effect of clove-based herbal mouthwash on radiation-induced oral mucositis in patients with head and neck cancer: a single-blind randomized preliminary study

    Directory of Open Access Journals (Sweden)

    Kong M

    2016-07-01

    delayed the time to onset of mucositis (26.6 days vs 24.5 days and reduced the maximum pain score (4.1 vs 4.9. However, these differences were not statistically significant. Conclusion: Although we could not find significant differences in some end points, this single-blind randomized study showed that a clove-based herbal mouthwash can have a potentially beneficial effect on minimizing or preventing radiation-induced oral mucositis in patients with head and neck cancer. To confirm the results of our study, well-designed randomized studies with large sample sizes will be required. Keywords: radiotherapy, mucositis, head and neck cancer, clove-based herbal mouthwash 

  3. 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.

  4. Natural Gradient Approach to Multichannel Blind Deconvolution

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    In this paper we study the geometrical structures of FIR filters and their application to multichannel blind deconvolution.First we introduce a Lie group structure and a Riemannian structure on the manifolds of the FIR filters.Then we derive the natural gradients on the manifolds using the isometry of the Riemannian metric.Using the natural gradient,we present a novel learning algorithm for blind deconvolution based on the minimization of mutual information.Some properties of the learning algorithm,such as equivariance and stability are also studied.Finally,the simulations are given to illustrate the effectiveness and validity of the proposed algorithm.

  5. Rapid Assessment of Avoidable Blindness in India.

    Directory of Open Access Journals (Sweden)

    John Neena

    Full Text Available BACKGROUND: Rapid assessment of avoidable blindness provides valid estimates in a short period of time to assess the magnitude and causes of avoidable blindness. The study determined magnitude and causes of avoidable blindness in India in 2007 among the 50+ population. METHODS AND FINDINGS: Sixteen randomly selected districts where blindness surveys were undertaken 7 to 10 years earlier were identified for a follow up survey. Stratified cluster sampling was used and 25 clusters (20 rural and 5 urban were randomly picked in each district.. After a random start, 100 individuals aged 50+ were enumerated and examined sequentially in each cluster. All those with presenting vision = 50 years were enumerated, and 94.7% examined. Based on presenting vision,, 4.4% (95% Confidence Interval[CI]: 4.1,4.8 were severely visually impaired (vision<6/60 to 3/60 in the better eye and 3.6% (95% CI: 3.3,3.9 were blind (vision<3/60 in the better eye. Prevalence of low vision (<6/18 to 6/60 in the better eye was 16.8% (95% CI: 16.0,17.5. Prevalence of blindness and severe visual impairment (<6/60 in the better eye was higher among rural residents (8.2%; 95% CI: 7.9,8.6 compared to urban (7.1%; 95% CI: 5.0, 9.2, among females (9.2%; 95% CI: 8.6,9.8 compared to males (6.5%; 95% CI: 6.0,7.1 and people above 70 years (20.6%; 95% CI: 19.1,22.0 compared to people aged 50-54 years (1.3%; 95% CI: 1.1,1.6. Of all blindness, 88.2% was avoidable. of which 81.9% was due to cataract and 7.1% to uncorrected refractive errors/uncorrected aphakia. CONCLUSIONS: Cataract and refractive errors are major causes of blindness and low vision and control strategies should prioritize them. Most blindness and low vision burden is avoidable.

  6. [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

  7. 一种基于ElGamal签名体制的代理多重盲签名方案%Proxy blind multi-signature scheme based on ElGamal signature

    Institute of Scientific and Technical Information of China (English)

    刘雯; 张建中

    2012-01-01

    Proxy multi-signature is that a proxy signer can represent the signing power of many original signers to generate a valid signature. Proxy blind multi-signature is the combination of proxy multi-signature and blind signature, and plays an important role in electronic voting and other reality. A proxy blind multi-signature scheme based on ElGamal signature is proposed and the correctness and security of the scheme are analyzed.%代理多重签名是指在一个代理签名方案中,一个代理签名人可以同时代表多个原始签名人的利益生成一个有效的签名.将代理多重签名和盲签名结合起来的代理多重盲签名,在电子选举等现实情况中有着重要的作用.提出一种基于E1Gamal签名体制的代理多重盲签名方案,对方案的正确性和安全性进行了分析和讨论.

  8. 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。

  9. Transferability of Virtual Reality, Simulation-Based, Robotic Suturing Skills to a Live Porcine Model in Novice Surgeons: A Single-Blind Randomized Controlled Trial.

    Science.gov (United States)

    Vargas, Maria V; Moawad, Gaby; Denny, Kathryn; Happ, Lindsey; Misa, Nana Yaa; Margulies, Samantha; Opoku-Anane, Jessica; Abi Khalil, Elias; Marfori, Cherie

    To assess whether a robotic simulation curriculum for novice surgeons can improve performance of a suturing task in a live porcine model. Randomized controlled trial (Canadian Task Force classification I). Academic medical center. Thirty-five medical students without robotic surgical experience. Participants were enrolled in an online session of training modules followed by an in-person orientation. Baseline performance testing on the Mimic Technologies da Vinci Surgical Simulator (dVSS) was also performed. Participants were then randomly assigned to the completion of 4 dVSS training tasks (camera clutching 1, suture sponge 1 and 2, and tubes) versus no further training. The intervention group performed each dVSS task until proficiency or up to 10 times. A final suturing task was performed on a live porcine model, which was video recorded and blindly assessed by experienced surgeons. The primary outcomes were Global Evaluative Assessment of Robotic Skills (GEARS) scores and task time. The study had 90% power to detect a mean difference of 3 points on the GEARS scale, assuming a standard deviation (SD) of 2.65, and 80% power to detect a mean difference of 3 minutes, assuming an SD of 3 minutes. There were no differences in demographics and baseline skills between the 2 groups. No significant differences in task time in minutes or GEARS scores were seen for the final suturing task between the intervention and control groups, respectively (9.2 [2.65] vs 9.9 [2.07] minutes, p = .406; and 15.37 [2.51] vs 15.25 [3.38], p = .603). The 95% confidence interval for the difference in mean task times was -2.36 to .96 minutes and for mean GEARS scores -1.91 to 2.15 points. Live suturing task performance was not improved with a proficiency-based virtual reality simulation suturing curriculum compared with standard orientation to the da Vinci robotic console in a group of novice surgeons. Published by Elsevier Inc.

  10. Effect of an Echinacea-Based Hot Drink Versus Oseltamivir in Influenza Treatment: A Randomized, Double-Blind, Double-Dummy, Multicenter, Noninferiority Clinical Trial.

    Science.gov (United States)

    Rauš, Karel; Pleschka, Stephan; Klein, Peter; Schoop, Roland; Fisher, Peter

    2015-12-01

    Echinacea has antiviral activity against influenza viruses in vitro and has traditionally been used for treatment of colds and flu. This randomized, double-blind, double-dummy, multicenter, controlled clinical trial compared a new echinacea formulation with the neuraminidase inhibitor oseltamivir, the gold standard treatment for influenza. Following informed consent, 473 patients with early influenza symptoms (≤48 hours) were recruited in primary care in the Czech Republic and randomized to either 5 days of oseltamivir followed by 5 days of placebo, or 10 days of an Echinacea purpurea-based formulation called Echinaforce Hotdrink (A. Vogel Bioforce AG, Roggwil, Switzerland). The proportion of recovered patients (influenza symptoms rated as absent or mild in the evening) was analyzed for noninferiority between treatment groups using a generalized Wilcoxon test with significance level α = 0.05 (2-sided) and using a CI approach in the per-protocol sample. Recovery from illness was comparable in the 2 treatment groups at 1.5% versus 4.1% after 1 day, 50.2% versus 48.8% after 5 days, and 90.1% versus 84.8% after 10 days of treatment with Echinaforce Hotdrink and oseltamivir, respectively. Noninferiority was demonstrated for each day and overall (95% CI, 0.487-0.5265 by generalized Wilcoxon test). Very similar results were obtained in the group with virologically confirmed influenza virus infections and in a retrospective analysis during the peak influenza period. The incidence of complications was lower with Echinaforce Hotdrink than with oseltamivir (2.46% vs 6.45%; P = 0.076) and fewer adverse events (particularly nausea and vomiting) were observed with Echinaforce Hotdrink. Echinaforce Hotdrink is as effective as oseltamivir in the early treatment of clinically diagnosed and virologically confirmed influenza virus infections with a reduced risk of complications and adverse events. It appears to be an attractive treatment option, particularly suitable for self

  11. Blind Detection of Composite Images Based on K-SVD Dictionary Learning%基于K-SVD字典学习的合成图像盲检测

    Institute of Scientific and Technical Information of China (English)

    王伟; 曾凤; 段新涛; 李洪均; 刘海升

    2013-01-01

    Digital images which have an inherent amount of noise typically uniform across the entire image is introduced by imaging process,if images with different noise levels are spliced together would leave an evidence of tampering.Base on this characteristic,in this paper we proposes a blind detection method using K-means singular valne deconposition(K-SVD) dictionary learning.A dictionary about sparse representation is obtained by training samples form composite image with K-SVD dictionary learning algorithm.Then the composite image is denoised by utilizing learned dictionary.By estimating the correlation coefficients of image blocks before and after denoise,the fogery regions can be found.Simulation results show its effectiveness in detecting forgery part in spliced images with different noise levels.The proposed method has good robustness against lossy JPEG compression,resampling and blurring.%一幅真实的图像中噪声特性是一致的,而由多幅图像内容拼接而成的合成图像噪声特性是不一致的.本文利用这一特点,提出了一种基于K均值奇异值分解(K-SVD)字典学习的合成图像盲检测方法.该方法首先通过K-SVD算法对合成图像进行训练得到其稀疏表示字典,然后利用学习得到的字典对背景噪声进行去除,最后根据去噪前后图像对应子块的相关系数异同实现篡改区域的检测与定位.实验结果表明,该方法对于鉴别含有不同背景噪声的合成图像具有显著效果,同时,算法对JPEG压缩、重采样和模糊等后处理操作都具有较好的鲁棒性.

  12. High-performance AlGaN-based solar-blind avalanche photodiodes with dual-periodic III-nitride distributed Bragg reflectors

    Science.gov (United States)

    Yao, Chujun; Ye, Xuanchao; Sun, Rui; Yang, Guofeng; Wang, Jin; Lu, Yanan; Yan, Pengfei; Cao, Jintao; Gao, Shumei

    2017-03-01

    Separate absorption and multiplication AlGaN solar-blind avalanche photodiodes with dual-periodic III-nitride distributed Bragg reflectors (DBRs) are numerically demonstrated. The designed devices exhibit an improved solar-blind characteristic with a maximum spectral responsivity of 0.184 A/W at λ = 284 nm owing to the optimized optical properties of the dual-periodic III-nitride DBRs. Compared with their conventional counterparts, an increased multiplication gain and a reduced breakdown voltage are achieved by using p-type Al0.15Ga0.85N layers with a lower Al content and multiplication layers. These improvements are attributed to the high p-doping efficiency and large hole ionization coefficient.

  13. Increasing accessibility to the blind of virtual environments, using a virtual mobility aid based on the "EyeCane": feasibility study.

    Directory of Open Access Journals (Sweden)

    Shachar Maidenbaum

    Full Text Available Virtual worlds and environments are becoming an increasingly central part of our lives, yet they are still far from accessible to the blind. This is especially unfortunate as such environments hold great potential for them for uses such as social interaction, online education and especially for use with familiarizing the visually impaired user with a real environment virtually from the comfort and safety of his own home before visiting it in the real world. We have implemented a simple algorithm to improve this situation using single-point depth information, enabling the blind to use a virtual cane, modeled on the "EyeCane" electronic travel aid, within any virtual environment with minimal pre-processing. Use of the Virtual-EyeCane, enables this experience to potentially be later used in real world environments with identical stimuli to those from the virtual environment. We show the fast-learned practical use of this algorithm for navigation in simple environments.

  14. Increasing accessibility to the blind of virtual environments, using a virtual mobility aid based on the "EyeCane": feasibility study.

    Science.gov (United States)

    Maidenbaum, Shachar; Levy-Tzedek, Shelly; Chebat, Daniel-Robert; Amedi, Amir

    2013-01-01

    Virtual worlds and environments are becoming an increasingly central part of our lives, yet they are still far from accessible to the blind. This is especially unfortunate as such environments hold great potential for them for uses such as social interaction, online education and especially for use with familiarizing the visually impaired user with a real environment virtually from the comfort and safety of his own home before visiting it in the real world. We have implemented a simple algorithm to improve this situation using single-point depth information, enabling the blind to use a virtual cane, modeled on the "EyeCane" electronic travel aid, within any virtual environment with minimal pre-processing. Use of the Virtual-EyeCane, enables this experience to potentially be later used in real world environments with identical stimuli to those from the virtual environment. We show the fast-learned practical use of this algorithm for navigation in simple environments.

  15. Effect of an Echinacea-Based Hot Drink Versus Oseltamivir in Influenza Treatment: A Randomized, Double-Blind, Double-Dummy, Multicenter, Noninferiority Clinical Trial

    OpenAIRE

    Karel Rauš; Stephan Pleschka; Peter Klein, MSc; Roland Schoop, MSc; Peter Fisher

    2015-01-01

    Background: Echinacea has antiviral activity against influenza viruses in vitro and has traditionally been used for treatment of colds and flu. Objectives: This randomized, double-blind, double-dummy, multicenter, controlled clinical trial compared a new echinacea formulation with the neuraminidase inhibitor oseltamivir, the gold standard treatment for influenza. Methods: Following informed consent, 473 patients with early influenza symptoms (≤48 hours) were recruited in primary care in...

  16. Effect of an Echinacea-Based Hot Drink Versus Oseltamivir in Influenza Treatment: A Randomized, Double-Blind, Double-Dummy, Multicenter, Noninferiority Clinical Trial

    OpenAIRE

    Karel Rauš; Stephan Pleschka; Peter Klein, MSc; Roland Schoop, MSc; Peter Fisher

    2015-01-01

    Background: Echinacea has antiviral activity against influenza viruses in vitro and has traditionally been used for treatment of colds and flu. Objectives: This randomized, double-blind, double-dummy, multicenter, controlled clinical trial compared a new echinacea formulation with the neuraminidase inhibitor oseltamivir, the gold standard treatment for influenza. Methods: Following informed consent, 473 patients with early influenza symptoms (≤48 hours) were recruited in primary care in...

  17. Visual impairment and blindness in Hungary.

    Science.gov (United States)

    Szabó, Dorottya; Sándor, Gábor László; Tóth, Gábor; Pék, Anita; Lukács, Regina; Szalai, Irén; Tóth, Georgina Zsófia; Papp, András; Nagy, Zoltán Zsolt; Limburg, Hans; Németh, János

    2017-08-21

    The aim of this study was to estimate the prevalence and causes of blindness, severe visual impairment (SVI), moderate visual impairment (MVI), and early visual impairment (EVI) and its causes in an established market economy of Europe. A cross-sectional population-based survey. A sample size of 3675 was calculated using the standard Rapid Assessment of Avoidable Blindness (RAAB) software in Hungary. A total of 105 clusters of 35 people aged 50 years or older were randomly selected with probability proportionate to size by the Hungarian Central Statistical Office. Households within the clusters were selected using compact segment sampling. Visual acuity (VA) was assessed with a Snellen tumbling E-chart with or without a pinhole in the households. The adjusted prevalences of bilateral blindness, SVI, MVI and EVI were 0.9% (95% CI: 0.6-1.2), 0.5% (95% CI: 0.2-0.7), 5.1% (95% CI: 4.3-5.9) and 6.9% (95% CI: 5.9-7.9), respectively. The major causes of blindness in Hungary were age-related macular degeneration (AMD; 27.3%) and other posterior segment diseases (27.3%), cataract (21.2%) and glaucoma (12.1%). Cataract was the main cause of SVI, MVI and EVI. Cataract surgical coverage (CSC) was 90.7%. Of all bilateral blindness in Hungary, 45.5% was considered avoidable. This study proved that RAAB methodology can be successfully conducted in industrialized countries, which often lack reliable epidemiologic data. The prevalence of blindness was relatively low, with AMD and other posterior segment diseases being the leading causes, and cataract is still a significant cause of visual impairment. © 2017 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  18. Fighting blindness with microelectronics.

    Science.gov (United States)

    Zrenner, Eberhart

    2013-11-06

    There is no approved cure for blindness caused by degeneration of the photoreceptor cells of the retina. However, there has been encouraging progress with attempts to restore vision using microelectronic retinal implant devices. Yet many questions remain to be addressed. Where is the best location to implant multielectrode arrays? How can spatial and temporal resolution be improved? What are the best ways to ensure the safety and longevity of these devices? Will color vision be possible? This Perspective discusses the current state of the art of retinal implants and attempts to address some of the outstanding questions.

  19. Blind reconstruction of linear scrambler

    Institute of Scientific and Technical Information of China (English)

    Hui Xie; Fenghua Wang; Zhitao Huang

    2014-01-01

    An algorithm based on eigenanalysis technique and Walsh-Hadamard transform (WHT) is proposed. The algorithm contains two steps. Firstly, the received sequence is divided into temporal windows, and a covariance matrix is computed. The li-near feedback shift register (LFSR) sequence is reconstructed from the first eigenvector of this matrix. Secondly, equations ac-cording to the recovered LFSR sequence are constructed, and the Walsh spectrum corresponding to the equations is computed. The feedback polynomial of LFSR is estimated from the Walsh spec-trum. The validity of the algorithm is verified by the simulation result. Final y, case studies are presented to il ustrate the perfor-mance of the blind reconstruction method.

  20. A Weak Quantum Blind Signature with Entanglement Permutation

    Science.gov (United States)

    Lou, Xiaoping; Chen, Zhigang; Guo, Ying

    2015-09-01

    Motivated by the permutation encryption algorithm, a weak quantum blind signature (QBS) scheme is proposed. It involves three participants, including the sender Alice, the signatory Bob and the trusted entity Charlie, in four phases, i.e., initializing phase, blinding phase, signing phase and verifying phase. In a small-scale quantum computation network, Alice blinds the message based on a quantum entanglement permutation encryption algorithm that embraces the chaotic position string. Bob signs the blinded message with private parameters shared beforehand while Charlie verifies the signature's validity and recovers the original message. Analysis shows that the proposed scheme achieves the secure blindness for the signer and traceability for the message owner with the aid of the authentic arbitrator who plays a crucial role when a dispute arises. In addition, the signature can neither be forged nor disavowed by the malicious attackers. It has a wide application to E-voting and E-payment system, etc.

  1. Multi-proxy Strong Blind Quantum Signature Scheme

    Science.gov (United States)

    Guo, Wei; Zhang, Jian-Zhong; Li, Yan-Ping; An, Wan

    2016-08-01

    A multi-proxy strong blind quantum signature scheme is proposed in this paper. An original signatory Alice delegates her signing authority to a group of proxy signatories by using a classical warrant. A blind factor is introduced by a sender U to blind a message, and the proxy signatories sign the message blindly via applying appropriate unitary operators. A receiver Bob verifies the generated signature with the help of an arbitrator Trent. The security of this scheme is based on a quantum key distribution protocol, a quantum one-time pad and other quantum properties. It is proved that our scheme has the properties of non-disavowal, non-counterfeit, multi-proxy, blindness, untraceability and can resist some common attacks.

  2. A THRESHOLD BLIND SIGNATURE FROM WEIL PAIRING ON ELLIPTIC CURVES

    Institute of Scientific and Technical Information of China (English)

    Cheng Xiangguo; Xu Weidong; Wang Xinmei

    2006-01-01

    The idea behind a (t, n) threshold blind signature is that a user can ask at least t out ofn players of a group to cooperate to generate a signature for a message without revealing its content. This paper first presents a new blind signature scheme from Weil pairing on elliptic curves. Based on this scheme, a threshold blind signature scheme is proposed. It is efficient and has the security properties of robustness and unforgeability. In the proposed scheme, the group manger is introduced to take the role of distributing the group secret key to each player. However, he cannot forge the players to generate partial blind signatures (Each partial blind signature depends on not only the secret key of the player, but also a random number the player picks). Compared with a threshold signature with a trusted third party, its advantage is obvious; Compared with a threshold signature without a trusted third party, it is more simple and efficient.

  3. Deaf, blind or deaf-blind: Is touch enhanced?

    Science.gov (United States)

    Papagno, Costanza; Cecchetto, Carlo; Pisoni, Alberto; Bolognini, Nadia

    2016-02-01

    When someone looses one type of sensory input, s/he may compensate by using the sensory information conveyed by other senses. To verify whether loosing a sense or two has consequences on a spared sensory modality, namely touch, and whether these consequences depend on the type of sensory loss, we investigated the effects of deafness and blindness on temporal and spatial tactile tasks in deaf, blind and deaf-blind people. Deaf and deaf-blind people performed the spatial tactile task better than the temporal one, while blind and controls showed the opposite pattern. Deaf and deaf-blind participants were impaired in temporal discrimination as compared to controls, while deaf-blind individuals outperformed blind participants in the spatial tactile task. Overall, sensory-deprived participants did not show an enhanced tactile performance. We speculate that discriminative touch is not so relevant in humans, while social touch is. Probably, more complex tactile tasks would have revealed an increased performance in sensory-deprived people.

  4. Double-blind, placebo-controlled, randomized study of chlorhexidine prophylaxis for 5-fluorouracil-based chemotherapy-induced oral mucositis with nonblinded randomized comparison to oral cooling (cryotherapy) in gastrointestinal malignancies

    DEFF Research Database (Denmark)

    Skovsgaard, T.; Bork, E.; Damstrup, L.

    2008-01-01

    BACKGROUND: The purpose was to evaluate prevention of oral mucositis (OM) using chlorhexidine compared with placebo and with oral cooling (cryotherapy) during fluorouracil (5-FU)-based chemotherapy in gastrointestinal (GI) cancer. METHODS: Patients with previously untreated GI cancer receiving...... bolus 5-FU/leucovorin chemotherapy were randomized to chlorhexidine mouthrinse 3 times a day for 3 weeks (Arm A), double-blind placebo (normal saline) with the same dose and frequency (Arm B), or cryotherapy with crushed ice 45 minutes during chemotherapy (Arm C). Patients self-reported on severity (CTC...... (33%) than in A (13%, Pcryotherapy. The latter is easy and inexpensive but has...

  5. Exploring medication use by blind patients in Saudi Arabia.

    Science.gov (United States)

    Kentab, Basma Y; Al-Rowiali, Kholuod Z; Al-Harbi, Rehab A; Al-Shammari, Nouf H; Balhareth, Wiam M; Al-Yazeed, Huda F

    2015-01-01

    To explore the characteristics of medication use and challenges experienced by the blind patients. This cross-sectional descriptive study included blind persons living in Saudi Arabia who were at least 18 years of age. Participants were recruited through a number of nongovernmental blind associations (in the central, western, eastern regions), universities, social networks, and specialized websites for the blind. A questionnaire was designed and administered via face-to-face meetings with participants and made available online through Google Docs. There were a total of 121 respondents of which 26 were excluded based on their ability to visually identify their medications or being medication information. The medication information and services provided by pharmacists were viewed as inadequate by 46%. The most common challenges encountered by blind patients were linked to drug identification (75%), dose recognition (82%), and identification of expiration date (92%). A large number of patients had to rely on persons with normal vision for dispensing and administering the medications. Pharmacists can no longer ignore the medication use problems encountered by the blind people. This study may serve as an initial step for planning improvements in pharmaceutical services provided to blind patients. The government, pharmaceutical companies and pharmacists must work in collaboration to address the special needs of the blind.

  6. Blind spot detection using vision for automotive applications

    Institute of Scientific and Technical Information of China (English)

    Miguel (A)ngel SOTELO; José BARRIGA

    2008-01-01

    This paper describes a vision-based system for blind spot detection (BSD) in intelligent vehicle applications. A camera is mounted in the lateral mirror of a car with the intention of visually detecting cars that are located in the so-called blind spot and cannot be perceived by the vehicle driver. The detection of cars in the blind spot is carried out using computer vision techniques,based on optical flow and a double-stage data clustering technique for robust vehicle detection.

  7. 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

  8. A New Blind Adaptive Array Antenna Based on CMA Criteria for M-Ary/SS Signals Suitable for Software Defined Radio Architecture

    Science.gov (United States)

    Kozuma, Miho; Sasaki, Atsushi; Kamiya, Yukihiro; Fujii, Takeo; Umebayashi, Kenta; Suzuki, Yasuo

    M-ary/SS is a version of Direct Sequence/Spread Spectrum (DS/SS) aiming to improve the spectral efficiency employing orthogonal codes. However, due to the auto-correlation property of the orthogonal codes, it is impossible to detect the symbol timing by observing correlator outputs. Therefore, conventionally, a preamble has been inserted in M-ary/SS, signals. In this paper, we propose a new blind adaptive array antenna for M-ary/SS systems that combines signals over the space axis without any preambles. It is surely an innovative approach for M-ary/SS. The performance is investigated through computer simulations.

  9. PA01.17. A clinical study to evaluate the effect of extract based herbal formulation on hypertension- a single blinded standard controlled randomized study

    Science.gov (United States)

    Agrawal, Satish; Pol, Hemant

    2012-01-01

    Purpose: In Ayurveda although there is no such terminology like hypertension but still this work is an approach to establish relationship between Hypertension & vitiated functioning of three governing forces of our body i.e. Tridosha and to treat Hypertension on Ayurvedic principles. The logic behind such correlation is based on the fact that, like other physiological processes, B.P. too is normal phenomenon of our body which is governed by Tridosha. After going through modern pathogenesis of primary hypertension and its symptomology, in present study it has been correlated with Vata Kaphaja Vikara with Rasavaha, Raktavaha and Manovahi Srotas as the seat of disease. Looking at its pathogenesis, the term Uccha Vyan Bala (exaggerated physiological functioning of Vyan Vayu leading to increase contractility of heart & blood vessels) can be coined for hypertension. Method: Subjective criteria Headache, Palpitation, Vertigo, Dyspnoea on walks and Fatigue. Objective criteria BP value recorded by sphygmomanometer in supine position. Final assessment of results; Subjective assessment 75 to 100% disappearance of symptoms effectively cured. 50 to 74% disappearance of symptoms well cured. 25 to 49% disappearance of symptoms fairly cured. 0 to 24% disappearance of symptoms poorly cured. Objective assessment Patient showing reduction in BP by 10mmHg Poorly cured; Patient showing reduction in BP between 11 to 20mmHg Fairly cured; Patient showing reduction in BP between 21 to 30 mmHg Well cured; Patient showing reduction in BP by more than 30 mmHg Effectively cured. Research methodology Type of study-Single blinded comparative study. Study site IPD and OPD department of Shubhdeep ayurved medical college, Indore (MP). Sample size 50 patients divided randomly into two equal groups. Group A given trial drug whereas Group B given control drug. Drug dosage and vehicle 1 capsule twice daily with lukewarm water after meals. Duration of treatment one month (examined at weekly intervals

  10. Molyneux's Question: A Window on Crossmodal Interplay in Blindness

    National Research Council Canada - National Science Library

    Valeria Occelli

    2014-01-01

    In 1688, the Irish scientist William Molyneux sent a letter to the philosopher John Locke in which he asked whether a man who had been born blind and whose experience of the world was based on senses...

  11. Training Senior Citizen Centers Staff in Blind Rehabilitation Techniques.

    Science.gov (United States)

    Asch, Celine

    1980-01-01

    The author discusses a project conducted in 1979 in which personnel from Arkansas Enterprises for the Blind trained staff members from community based programs for the elderly in techniques designed to involve and assist visually impaired senior citizens. (Author)

  12. Justifications Shape Ethical Blind Spots

    NARCIS (Netherlands)

    Pittarello, Andrea; Leib, Margarita; Gordon-Hecker, Tom; Shalvi, Shaul

    2015-01-01

    To some extent, unethical behavior results from people's limited attention to ethical considerations, which results in an ethical blind spot. Here, we focus on the role of ambiguity in shaping people's ethical blind spots, which in turn lead to their ethical failures. We suggest that in ambiguous se

  13. Overview on Deaf-Blindness

    Science.gov (United States)

    ... build relationships and become the eventual basis for language learning. As the child who is deaf-blind becomes ... those near them, deaf-blindness fosters opportunities for learning and mutual ... M. (Eds.), (1993). Second edition. A model service delivery system for persons ...

  14. Blind Cognitive MAC Protocols

    CERN Document Server

    Mehanna, Omar; Gamal, Hesham El

    2008-01-01

    We consider the design of cognitive Medium Access Control (MAC) protocols enabling an unlicensed (secondary) transmitter-receiver pair to communicate over the idle periods of a set of licensed channels, i.e., the primary network. The objective is to maximize data throughput while maintaining the synchronization between secondary users and avoiding interference with licensed (primary) users. No statistical information about the primary traffic is assumed to be available a-priori to the secondary user. We investigate two distinct sensing scenarios. In the first, the secondary transmitter is capable of sensing all the primary channels, whereas it senses one channel only in the second scenario. In both cases, we propose MAC protocols that efficiently learn the statistics of the primary traffic online. Our simulation results demonstrate that the proposed blind protocols asymptotically achieve the throughput obtained when prior knowledge of primary traffic statistics is available.

  15. High detectivity solar-blind high-temperature deep-ultraviolet photodetector based on multi-layered (l00) facet-oriented β-Ga₂O₃ nanobelts.

    Science.gov (United States)

    Zou, Rujia; Zhang, Zhenyu; Liu, Qian; Hu, Junqing; Sang, Liwen; Liao, Meiyong; Zhang, Wenjun

    2014-05-14

    Fabrication of a high-temperature deep-ultraviolet photodetector working in the solar-blind spectrum range (190-280 nm) is a challenge due to the degradation in the dark current and photoresponse properties. Herein, β-Ga2O3 multi-layered nanobelts with (l00) facet-oriented were synthesized, and were demonstrated for the first time to possess excellent mechanical, electrical properties and stability at a high temperature inside a TEM studies. As-fabricated DUV solar-blind photodetectors using (l00) facet-oriented β-Ga2O3 multi-layered nanobelts demonstrated enhanced photodetective performances, that is, high sensitivity, high signal-to-noise ratio, high spectral selectivity, high speed, and high stability, importantly, at a temperature as high as 433 K, which are comparable to other reported semiconducting nanomaterial photodetectors. In particular, the characteristics of the photoresponsivity of the β-Ga2O3 nanobelt devices include a high photoexcited current (>21 nA), an ultralow dark current (below the detection limit of 10(-14) A), a fast time response (photodetectors or optical switches for high-temperature environment.

  16. β-Ga2O3 solar-blind deep-ultraviolet photodetector based on a four-terminal structure with or without Zener diodes

    Science.gov (United States)

    Qian, L. X.; Liu, X. Z.; Sheng, T.; Zhang, W. L.; Li, Y. R.; Lai, P. T.

    2016-04-01

    A four-terminal photodetector was fabricated on the ( 2 ¯ 01 )-dominant β-Ga2O3 thin film which was deposited in a plasma-assisted molecular beam epitaxy system. The suitability of this film for solar-blind DUV detection was proved by its transmission spectra. Moreover, the device operating in a specific voltage-current mode can accurately detect the DUV radiation both qualitatively and quantitatively. Accordingly, a dark/photo voltage ratio of 15 was achieved, which is comparable to that of previously-reported β-Ga2O3 interdigital metal-semiconductor-metal photoconductor. More importantly, the aperture ratio of our proposed device exceeds 80%, nearly doubling that of the conventional interdigital metal-semiconductor-metal devices including photoconductor and Schottky-type photodiode, which can intensively benefit the detection efficiency. Furthermore, it was found the dark/photo voltage ratio was nearly trebled with the assistance of two Zener diodes, and further enhancement can be expected by increasing the operating current and/or adopting Zener diodes with smaller Zener voltage. Therefore, this work provides a promising alternative for solar-blind DUV detection.

  17. 基于Haptic技术的盲人辅助路径诱导服务研制%Development of route guidance for the blind based on Haptic technology

    Institute of Scientific and Technical Information of China (English)

    王冠生; 郑江华; 瓦哈甫·哈力克; 刘敬强; 李荣立

    2012-01-01

    Having sharp sense of touch resources form the ordinary, this study integrated the application of GPS, GIS and Haptic (vibration) technology to develop a type of new mode route guidance for the blind. This model provides different vibration to the blind under two circumstances: road key nodes and deviation planning path. It resists the vibration noise, reflects timely and has high effectiveness etc. It has the very high value to use.%针对盲人具有敏锐于常人的触觉资源,综合应用GPS、GIS和Haptic(震动)等技术,开发研制了一种盲人路径诱导新模式.该模式向盲人提供路口等关键节点和偏离规划路径两种情况下的差异性震动,具有抗噪声干扰、反馈及时和高有效性等优点,具有很高的使用价值.

  18. β-Ga2O3 solar-blind deep-ultraviolet photodetector based on a four-terminal structure with or without Zener diodes

    Directory of Open Access Journals (Sweden)

    L. X. Qian

    2016-04-01

    Full Text Available A four-terminal photodetector was fabricated on the ( 2 ¯ 01 -dominant β-Ga2O3 thin film which was deposited in a plasma-assisted molecular beam epitaxy system. The suitability of this film for solar-blind DUV detection was proved by its transmission spectra. Moreover, the device operating in a specific voltage-current mode can accurately detect the DUV radiation both qualitatively and quantitatively. Accordingly, a dark/photo voltage ratio of 15 was achieved, which is comparable to that of previously-reported β-Ga2O3 interdigital metal-semiconductor-metal photoconductor. More importantly, the aperture ratio of our proposed device exceeds 80%, nearly doubling that of the conventional interdigital metal-semiconductor-metal devices including photoconductor and Schottky-type photodiode, which can intensively benefit the detection efficiency. Furthermore, it was found the dark/photo voltage ratio was nearly trebled with the assistance of two Zener diodes, and further enhancement can be expected by increasing the operating current and/or adopting Zener diodes with smaller Zener voltage. Therefore, this work provides a promising alternative for solar-blind DUV detection.

  19. Separación ciega de fuentes no-determinada aplicada a mezclas de voz con base en la transformada wavelet discreta Undetermined blind source separation of speech mixtures based on discrete wavelet transform

    Directory of Open Access Journals (Sweden)

    Camilo Andrés Lemus

    2012-12-01

    Full Text Available La separación ciega de fuentes, conocida como BSS por sus siglas en inglés (Blind Source Separation, es una técnica de procesamiento de señales que consiste en estimar fuentes en señales mezcladas linealmente, utilizando métodos como el ICA, para señales fuentes estadísticamente independientes. Uno de los algoritmos BSS más conocidos es el algoritmo JADE, el cual exige que el número de señales independientes coincida con el número de señales observadas (sensores. En situaciones reales, el número de sensores es menor al número de señales fuentes (BSS no-determinado y el problema no tiene solución. En este proyecto se propone una solución para BSS no-determinado, adicionando una etapa de preprocesamiento y una etapa de descomposición basada en la transformada wavelet discreta. Nuestro modelo, el cual hemos denominado DWT+BSS, crea una señal virtual observada a partir de una señal real observada y utiliza los coeficientes wavelet de las señales observadas como entradas al algoritmo clásico JADE. El modelo se valida con señales de voz y audio, obteniendo índices de similitud entre las señales fuentes y las estimadas por encima de 0,7.Blind Source Separation, BSS, is a signal processing technique which estimates sources from linearly mixed signals and it uses methods such as ICA for sources that are statistically independent. Among the best known BSS algorithms is the JADE method, which requires that the number of independent signals match the number of observed signals (sensors. In the real world, the number of sensors is lower than the number of sources (undetermined BSS and therefore the problem has no solution. This work proposes a solution for undetermined BSS by pre-processing and decomposition stages based on the Discrete Wavelet Transform (DWT. Our proposal, which it is known as DWT+BSS, creates a virtual observed signal from a real observed signal and it uses the wavelet coefficients of the observed signals as the

  20. 基于红外条码的盲人扑克游戏辅助仪的设计%Design and implementation of blind poker game auxiliary instrument based on infrared scanning bar code

    Institute of Scientific and Technical Information of China (English)

    景亚霓; 杨海平

    2014-01-01

    The paper designs a blind poker game auxiliary instrument based on bar code technology, embedded system and voice chip technology. The instrument has the characteristics of compact structure , simple and convenient operation and embed popular poker game program, thus users can conveniently select the type of game according to their interest. Its main feature is that it can broadcast information that others played poker and supplies situation of yourself poker in hands by earplug if need. The auxiliary instrument makes the blind to get poke information by "listen" instead of "touch", so that blind and low vision people can play cards as a normal person even if he does not know Braille. In other hand, some problem can be avoided, such as mistake of player distinguishing Braille.%设计了一款基于集条形码技术、嵌入式系统及语音芯片技术于一体、结构紧凑、操作简单方便的盲人扑克游戏辅助仪。该装置设计了常见的扑克游戏程序,使用者可根据兴趣方便地选择游戏种类。其主要特点是利用语音技术能够实时播报其他人的出牌信息并可根据需要耳机播报本人手中牌的信息,让盲人用“听”牌代替了“摸”牌,使盲人以及不懂盲文的低视力人群能像正常人一样打扑克、玩桥牌等,克服了现有低视力群体打牌游戏中常见的问题,如盲文识别错误等。

  1. 基于频域盲解卷积的齿轮箱复合故障声学诊断%Acoustical diagnosis for gear box combined failures based on frequency domain blind deconvolution

    Institute of Scientific and Technical Information of China (English)

    潘楠; 伍星; 迟毅林; 柳小勤; 刘畅

    2013-01-01

    针对复杂声场环境中齿轮箱复合故障特征提取,提出基于频域盲解卷积的声学诊断方法.该方法通过形态滤波滤除非调制信号,结合改进复数固定点算法优选复独立分量,进而通过复独立分量J-散度解决独立分量间次序不确定性问题.通过计算机仿真及实际环境下齿轮箱复合故障声信号提取实验验证该算法的有效性.%Aiming at gear box combined failure feature extraction in complex sound field, an acoustic fault detection method based on the frequency domain blind deconvolution was proposed. According to the frequency-domain blind deconvolution, the morphological filtering was firstly used to extract modulated features embedded in the observed signals, then the CFPA algorithm was employed to do complex-domain blind separation, finally the J-divergences of complex independent components were taken as distance measures to resolve the permutation. Tests using simulated and real machine sound signals were conducted. The results demonstrated that this proposed method can be efficiently applied to gear box combined failure detection in practice. Finally, the main problems to be studied further in this area were pointed out.

  2. 基于Haptic技术的盲人路径诱导辅具应用研究现状%Research status of applications of route guidance aids for the blind based on haptic technology

    Institute of Scientific and Technical Information of China (English)

    王冠生; 郑江华; 瓦哈甫·哈力克; 刘海亮

    2013-01-01

    触觉(Haptic)技术信息表达是一种有效的人机交互模式和信息传递方式,并作为信息传递的重要通道用于盲人导航/路径诱导辅具领域,弥补了在特定条件下声音的缺点与不足.对盲人导航/路径诱导辅具总体情况进行了概述;结合空间认知介绍了基于Haptic技术的盲人导航/路径诱导辅具研究现状与应用;分析了基于Haptic技术的盲人导航/路径诱导辅具在今后的发展趋势和存在的问题,并讨论了应用前景.%Haptic technical information expression is an effective human-computer interaction and information transfer mode. It makes up the shortcomings of sound under certain conditions and be an important channel of information transfer for the field of blind navigation/route guidance. General situation of navigation/route guidance aids for the blind is outlined. Recent research and applications of navigation/route guidance for the blind based on haptic technology integrated spatial cognition is introduced. Existing problems at present and development trends in the future is pointed out,and application prospect is discussed.

  3. Blind decoding algorithm of punctured convolutional codes based on improved WHT%基于改进Walsh-Hadamard变换的删除卷积码盲解码算法

    Institute of Scientific and Technical Information of China (English)

    戚林; 郝士琦; 王磊

    2011-01-01

    针对高误码率情况下删除卷积码的盲解码问题,提出了一种删除卷积码的盲解码算法.通过采用改进的沃尔什-哈达马变换(Walsh-Hadamard translate,WHT),识别出删除卷积码的高维校验矩阵;再基于源卷积码的生成矩阵与校验矩阵间的约束关系,求出了源卷积码的最佳生成多项式和删除模式,并提出了码字同步的方法,最终按识别出来的参数构建盲解码模型,实现了删除卷积码的盲解码.仿真结果表明,在误码率低于0.01,的情况下,该算法的译码正确率能达到93%.%In order to solve the problem of blind decoding punctured convolutional codes at high bit-error rates, this paper proposed a blind decoding algorithm. Through applying the advanced Walsh-Hadamard transform, recognized the high dimensionality parity-check matrix of punctured convolutional codes. Moreover, solved the generator matrix and puncture map of the source convolutional codes based on the constraint relationship between the parity-check matrix and the generator matrix. Then proposed a method of codeword synchronization. According to the recognition results, established a model of blind decoding of punctured convolutional codes. The simulation results show, the bit correct rate after decoding of this algorithm can be up to 93% under the condition of BER lower than 0.01.

  4. A segmentation method of color blindness detection image based on simplified PCNN%一种基于简化PCNN的色盲检测图分割方法

    Institute of Scientific and Technical Information of China (English)

    郭业才; 蒋峰; 龚溪

    2013-01-01

    在色盲检测图及脉冲耦合神经网络(pulse-coupled neural networks,简称PCNN)的基础上,提出一种基于简化PCNN模型的色盲检测图分割方法,该方法首先根据欧式距离计算彩色图像色差,通过设定一个合适的阈值,将与红色相似的颜色替换成白色,初步分离图像中的目标与背景,对预处理后的色盲检测图像,用典型的PCNN简化模型对其红色分量进行分割,最后用形态学闭运算优化得到最终的分割结果.实验结果表明,该方法能准确分割出色盲图像中的图形,且简单有效.%On the basis of the color blindness detection images and pulse coupled neural network (PCNN) , a segmentation method of color blindness detection image based on simplified PCNN was proposed. In this proposed method, the chromatic aberration was computed by Euclidean distance, the color similar to red was replaced with white by setting an appropriate threshold, then the target and background of image were preliminary separated, and the red component after pretreatment was segmented via using the typical simplified PCNN model, and finally the segmentation image was optimized by morphological closing operation. The experimental results showed that the method not only could accurately segment the color blindness images but also was simple and effective.

  5. Study on Map Color Design for Color Blindness Based on Geographical Attribute Scaling%利用地理属性量表的色盲人群地图色彩设计研究

    Institute of Scientific and Technical Information of China (English)

    汪华; 朱海红; 李霖

    2012-01-01

    根据地图表达地理属性的量表性质,将地图设色方案分为定性设色、顺序设色和双向设色等3种方式。基于这3种地图设色方式的特点,根据红一绿色盲的光谱特性,设计了一系列实验地图,通过颜色辨识的心理学实验,分析了红一绿色盲的视觉特征,初步揭示出一些针对红一绿色盲人群使用的地图设色原则,为制作红一绿色盲人群使用的地图提供了有效的参考。%Lack of study on principles of map design for color blindness leads to no such maps available for the color blindness, which is challenging cartography. Since red-green color-vi- sion impairment takes 95% of the total color blindness, it is important to study on mp colordesign for those people. Based on characteristics of geographical attribute scaling, three col- or schemes (qualitative scheme, sequential scheme, diverging scheme) for maps are exam- ined to that purpose. In order to observe features of map color used for red-green color-vision impairment, a series of color maps are made according to spectrum characters of the red- green color-vision impairment, and used for color psychological experiments. From these ex- periments, a part of principle of map colors used for red-green color-vision impairment is drawn out, which can be a good reference for making such maps.

  6. 基于三阶累积量的稳健盲波束形成方法%Robust blind beamforming algorithm based on third-order cumulants

    Institute of Scientific and Technical Information of China (English)

    王荣博; 侯朝焕

    2011-01-01

    The goal of blind beamforming is to recover source signals only from the output of array without any a priori information about the array manifold. For blind separation of the independent sources, Cardoso and Souloumiac proposed an effectively blind beamforming method (JADE) using fourth-order cumulant. However, the high computation complexity of this method limits its applicability in practical problems. In many applications, the source signals have nonzero third-order cumulant duo to the fact that they obey asymmetric distribution. In this paper, a new method is proposed to separate independent sources with nonzero third-order cumulant, which estimates mixing matrix by jointly diagonalizing several matrices formed by the third-order cumulants of array data. Contrary to JADE method, the proposed method has much lower computation complexity and is more robust to the estimation errors resulting from finite sampling data.%盲波束形成的目的就是在不知道阵列流形先验信息的情况下,从阵列输出数据中恢复出源信号.对于独立源信号的盲分离,Cardoso和Souloumiac提出了一种基于四阶累积量的盲波束形成方法(Joint Approximate Diagonalisation of Eigen-matrices,JADE).然而,巨大的计算量限制了该方法在工程中的应用.而在实际应用中很多信号并不服从对称分布,因而具有三阶累积量.为此,通过联合对角化由接收数据三阶累积量构造的一系列矩阵来估计混合矩阵,进而实现盲波束形成.与JADE相比,该方法具有较小的计算量,并且对于有限采样数据造成的估计误差更加稳健.

  7. Corneal blindness: prevention, treatment and rehabilitation

    Directory of Open Access Journals (Sweden)

    Matthew J Burton

    2009-12-01

    Full Text Available Blindness from corneal disease is a major ophthalmic public health problem. There are three important elements to addressing corneal blindness: prevention, treatment, and rehabilitation.

  8. Euro Banknote Recognition System for Blind People

    Directory of Open Access Journals (Sweden)

    Larisa Dunai Dunai

    2017-01-01

    Full Text Available This paper presents the development of a portable system with the aim of allowing blind people to detect and recognize Euro banknotes. The developed device is based on a Raspberry Pi electronic instrument and a Raspberry Pi camera, Pi NoIR (No Infrared filter dotted with additional infrared light, which is embedded into a pair of sunglasses that permit blind and visually impaired people to independently handle Euro banknotes, especially when receiving their cash back when shopping. The banknote detection is based on the modified Viola and Jones algorithms, while the banknote value recognition relies on the Speed Up Robust Features (SURF technique. The accuracies of banknote detection and banknote value recognition are 84% and 97.5%, respectively.

  9. Euro Banknote Recognition System for Blind People.

    Science.gov (United States)

    Dunai Dunai, Larisa; Chillarón Pérez, Mónica; Peris-Fajarnés, Guillermo; Lengua Lengua, Ismael

    2017-01-20

    This paper presents the development of a portable system with the aim of allowing blind people to detect and recognize Euro banknotes. The developed device is based on a Raspberry Pi electronic instrument and a Raspberry Pi camera, Pi NoIR (No Infrared filter) dotted with additional infrared light, which is embedded into a pair of sunglasses that permit blind and visually impaired people to independently handle Euro banknotes, especially when receiving their cash back when shopping. The banknote detection is based on the modified Viola and Jones algorithms, while the banknote value recognition relies on the Speed Up Robust Features (SURF) technique. The accuracies of banknote detection and banknote value recognition are 84% and 97.5%, respectively.

  10. Emergence of Blind Areas in Information Spreading

    CERN Document Server

    Zhang, Zi-Ke; Han, Xiao-Pu; Liu, Chuang

    2013-01-01

    Recently, contagion-based (disease, information, etc.) spreading on social networks has been extensively studied. In this paper, other than traditional full interaction, we propose a partial interaction based spreading model, considering that the informed individuals would transmit information to only a certain fraction of their neighbors due to the transmission ability in real-world social networks. Simulation results on three representative networks (BA, ER, WS) indicate that the spreading efficiency is highly correlated with the network heterogeneity. In addition, a special phenomenon, namely \\emph{Information Blind Areas} where the network is separated by several information-unreachable clusters, will emerge from the spreading process. Furthermore, we also find that the size distribution of such information blind areas obeys power-law-like distribution, which has very similar exponent with that of site percolation. Detailed analyses show that the critical value is decreasing along with the network heterog...

  11. Euro Banknote Recognition System for Blind People

    Science.gov (United States)

    Dunai Dunai, Larisa; Chillarón Pérez, Mónica; Peris-Fajarnés, Guillermo; Lengua Lengua, Ismael

    2017-01-01

    This paper presents the development of a portable system with the aim of allowing blind people to detect and recognize Euro banknotes. The developed device is based on a Raspberry Pi electronic instrument and a Raspberry Pi camera, Pi NoIR (No Infrared filter) dotted with additional infrared light, which is embedded into a pair of sunglasses that permit blind and visually impaired people to independently handle Euro banknotes, especially when receiving their cash back when shopping. The banknote detection is based on the modified Viola and Jones algorithms, while the banknote value recognition relies on the Speed Up Robust Features (SURF) technique. The accuracies of banknote detection and banknote value recognition are 84% and 97.5%, respectively. PMID:28117703

  12. Blind integrity verification of medical images.

    Science.gov (United States)

    Huang, Hui; Coatrieux, Gouenou; Shu, Huazhong; Luo, Limin; Roux, Christian

    2012-11-01

    This work presents the first method of digital blind forensics within the medical imaging field with the objective to detect whether an image has been modified by some processing (e.g. filtering, lossy compression and so on). It compares two image features: the Histogram statistics of Reorganized Block-based Discrete cosine transform coefficients (HRBD), originally proposed for steganalysis purposes, and the Histogram statistics of Reorganized Block-based Tchebichef moments (HRBT). Both features serve as input of a set of SVM classifiers built in order to discriminate tampered images from original ones as well as to identify the nature of the global modification one image may have undergone. Performance evaluation, conducted in application to different medical image modalities, shows that these image features can help, independently or jointly, to blindly distinguish image processing or modifications with a detection rate greater than 70%. They also underline the complementarity of these features.

  13. Scan blindness in infinite phased arrays of printed dipoles

    Science.gov (United States)

    Pozar, D. M.; Schaubert, D. H.

    1984-01-01

    A comprehensive study of infinite phased arrays of printed dipole antennas is presented, with emphasis on the scan blindness phenomenon. A rigorous and efficient moment method procedure is used to calculate the array impedance versus scan angle. Data are presented for the input reflection coefficient for various element spacings and substrate parameters. A simple theory, based on coupling from Floquet modes to surface wave modes on the substrate, is shown to predict the occurrence of scan blindness. Measurements from a waveguide simulator of a blindness condition confirm the theory.

  14. New Blind Graphic Printing Technology Based on Canny Operator%基于caany算子的新型盲用图形生成技术

    Institute of Scientific and Technical Information of China (English)

    李博; 王治平; 刘俊标; 方光荣

    2011-01-01

    Nowadays , Graphic printing becomes more and more important for the blind. As a new Braille printing tool, New Braille Printer(NBP) has overcome many shortcomings of traditional Braille printer. But, till now, the NBP could't has the functin of graphic printing. In order to improve the new Braille printer, a blind graphic printing method has been proposed. Considering the characteristics of the printing image, it utilized loop iteration method to select Canny operators with different thresholds, and then, took edge detection on the printing image to gained a series of edge images with the selected Canny operators. The accurate shape information of printing image was translated into NBP's control information, then the control information was used to control the NBP to print the blind graphic which gained from iterative calculation of this edge images. This method has been test on NBP, and blind graphics were printed on A4 paper clearly and completely.%随着信息技术的发展,盲用图形对于盲人而言,变得越来越重要。新型盲文打印机作为盲文印刷的新型工具,它克服了传统盲文印刷的许多缺点,但是,目前该盲文打印机还不具备打印盲文图形的功能,为了完善新型盲文打印机,本文针对待打印的盲文图像的特点,采用循环迭代的方式,选择不同阈值的Canny算子对待打印图像进行边缘提取,并对所得到的一系列的边缘图像进行迭代计算,从而实现了待打印图像边缘特征的精确提取。待打印图像的边缘信息最终被转化为新型盲文打印机的控制信息控制新型盲文打印机完成打印,生成盲用图形,从而实现了新型盲文打印机图形打印功能。目前,该方法已经在新型盲文打印机试验,成功的实现了待打印图像在A4纸张上的清晰完整的打印。

  15. Effect of household-based drinking water chlorination on diarrhoea among children under five in Orissa, India: a double-blind randomised placebo-controlled trial.

    Directory of Open Access Journals (Sweden)

    Sophie Boisson

    2013-08-01

    Full Text Available BACKGROUND: Boiling, disinfecting, and filtering water within the home can improve the microbiological quality of drinking water among the hundreds of millions of people who rely on unsafe water supplies. However, the impact of these interventions on diarrhoea is unclear. Most studies using open trial designs have reported a protective effect on diarrhoea while blinded studies of household water treatment in low-income settings have found no such effect. However, none of those studies were powered to detect an impact among children under five and participants were followed-up over short periods of time. The aim of this study was to measure the effect of in-home water disinfection on diarrhoea among children under five. METHODS AND FINDINGS: We conducted a double-blind randomised controlled trial between November 2010 and December 2011. The study included 2,163 households and 2,986 children under five in rural and urban communities of Orissa, India. The intervention consisted of an intensive promotion campaign and free distribution of sodium dichloroisocyanurate (NaDCC tablets during bi-monthly households visits. An independent evaluation team visited households monthly for one year to collect health data and water samples. The primary outcome was the longitudinal prevalence of diarrhoea (3-day point prevalence among children aged under five. Weight-for-age was also measured at each visit to assess its potential as a proxy marker for diarrhoea. Adherence was monitored each month through caregiver's reports and the presence of residual free chlorine in the child's drinking water at the time of visit. On 20% of the total household visits, children's drinking water was assayed for thermotolerant coliforms (TTC, an indicator of faecal contamination. The primary analysis was on an intention-to-treat basis. Binomial regression with a log link function and robust standard errors was used to compare prevalence of diarrhoea between arms. We used

  16. 基于McEliece公钥密码体制的盲签名算法研究%Blind Signature Scheme Based on McEliece Public Key Cryptosystem

    Institute of Scientific and Technical Information of China (English)

    赵程程; 李子臣; 刘念; 阎晓妲

    2012-01-01

    Due to the threat of quantum computer on public - key cryptography, the public key cryptosystems against quantum computing has become the focus of research in information security field. A blind sig- nature based on McEliece public key cryptography was proposed aiming at protecting of consumers'anonymi- ty. By Hash on a message and blind process ensure signed message and behavior cannot be linked. At the same time the signature of receiver's identity is kept secret and will never be leaked out, with unconditional intractability and security for this kind of blind signature is analyzed. Result shows that this model has the advantages of inheriting the security of McEliece public-key cryptography, having the general basic proper- ties of digital signatures and blind signatures, resisting quantum computer attack and eventually has a very strong security.%由于量子计算机对现用公钥密码体制的威胁,抵抗量子计算的公钥密码体制已经成为信息安全领域研究的重点。针对消费者的匿名性保护问题,本文提出一种基于McEliece公钥密码体制的盲签名算法。通过对消息进行Hash,盲化和去盲过程,保证签名的消息与签署行为不可链接,且永远不会被泄露,具有无条件不可追踪性。文章还对这种盲签名的安全性进行分析,分析结果表明,此模型既继承了McEliece公钥密码体制的安全性,能抵抗量子计算机的攻击,也具有一般数字签名和盲签名的基本性质,具有很强的安全性。

  17. Blind compensation for multi-AWACS cooperation based on aerial defence and warning%基于防空警戒任务的多预警机协同补盲

    Institute of Scientific and Technical Information of China (English)

    王国师; 李强; 代科学; 杨征; 谢毓湘

    2012-01-01

    在作战环境日益复杂的情况下,多预警机进行协同补盲,不仅可以扩大探测范围,大大增强抵抗“四大威胁”的能力,而且此地面雷达网具有更好的低空、超低空探测能力.研究了多预警机执行防空警戒任务时的协同补盲问题.首先,给出了预警机探测总区域、探测强效区和弱效区的定义,并分别建立了数学模型.其次,对预警机的顶空盲区、底空盲区、机体遮挡盲区、转弯盲区进行了分析和建模.然后,给出了基于防空警戒任务的多预警机协同补盲模型.最后,通过仿真证明了模型的有效性.%Under the circumstances at which the battle surroundings are becoming more and more complex, blind compensation of multi-airborne warning and control system (AWACS) cooperation can not only expand detection range and enhance to resistance the "{our threats", but also detect the larger area in the low altitude and super low altitude. The problem of blind compensation for multi-AWACS cooperation is researched based on the task of aerial defence and warning. Firstly, the definitions of the total detection area, strong detcetion area and poor detection area are given, and the mathematical models are establshed respectively. Secondly, the blind areas of AWACS are analyzed and modelled. Thirdly, the model of blind compensation of multi-AWACS cooperation is proposed. Finally, simulation results prove the effectiveness of the proposed model.

  18. [Simulation-based training and OR apprenticeship for medical students : A prospective, randomized, single-blind study of clinical skills].

    Science.gov (United States)

    Ott, T; Schmidtmann, I; Limbach, T; Gottschling, P F; Buggenhagen, H; Kurz, S; Pestel, G

    2016-11-01

    Simulation-based training (SBT) has developed into an established method of medical training. Studies focusing on the education of medical students have used simulation as an evaluation tool for defined skills. A small number of studies provide evidence that SBT improves medical students' skills in the clinical setting. Moreover, they were strictly limited to a few areas, such as the diagnosis of heart murmurs or the correct application of cricoid pressure. Other studies could not prove adequate transferability from the skills gained in SBT to the patient site. Whether SBT has an effect on medical students' skills in anesthesiology in the clinical setting is controversial. To explore this issue, we designed a prospective, randomized, single-blind trial that was integrated into the undergraduate anesthesiology curriculum of our department during the second year of the clinical phase of medical school. This study intended to explore the effect of SBT on medical students within the mandatory undergraduate anesthesiology curriculum of our department in the operating room with respect to basic skills in anesthesiology. After obtaining ethical approval, the participating students of the third clinical semester were randomized into two groups: the SIM-OR group was trained by a 225 min long SBT in basic skills in anesthesiology before attending the operating room (OR) apprenticeship. The OR-SIM group was trained after the operating room apprenticeship by SBT. During SBT the students were trained in five clinical skills detailed below. Further, two clinical scenarios were simulated using a full-scale simulator. The students had to prepare the patient and perform induction of anesthesia, including bag-mask ventilation after induction in scenario 1 and rapid sequence induction in scenario 2. Using the five-point Likert scale, five defined skills were evaluated at defined time points during the study period. 1) application of the safety checklist, 2) application of

  19. A double-blind randomised controlled trial of a natural oil-based emulsion (Moogoo Udder Cream® containing allantoin versus aqueous cream for managing radiation-induced skin reactions in patients with cancer

    Directory of Open Access Journals (Sweden)

    Chan Raymond

    2012-07-01

    Full Text Available Abstract Background Radiation-induced skin reaction (RISR is one of the most common and distressing side effects of radiotherapy in patients with cancer. It is featured with swelling, redness, itching, pain, breaks in skin, discomfort, and a burning sensation. There is a lack of convincing evidence supporting any single practice in the prevention or management of RISR. Methods/Designs This double-blinded randomised controlled trial aims to investigate the effects of a natural oil-based emulsion containing allantoin (as known as Moogoo Udder Cream® versus aqueous cream in reducing RISR, improving pain, itching and quality of life in this patient group. One group will receive Moogoo Udder Cream®. Another group will receive aqueous cream. Outcome measures will be collected using patient self-administered questionnaire, interviewer administered questionnaire and clinician assessment at commencement of radiotherapy, weekly during radiotherapy, and four weeks after the completion of radiotherapy. Discussion Despite advances of radiologic advances and supportive care, RISR are still not well managed. There is a lack of efficacious interventions in managing RISR. While anecdotal evidence suggests that Moogoo Udder Cream® may be effective in managing RISR, research is needed to substantiate this claim. This paper presents the design of a double blind randomised controlled trial that will evaluate the effects of Moogoo Udder Cream® versus aqueous cream for managing in RISR in patients with cancer. Trial registration ACTRN 12612000568819

  20. 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

  1. Perceptual Repetition Blindness Effects

    Science.gov (United States)

    Hochhaus, Larry; Johnston, James C.; Null, Cynthia H. (Technical Monitor)

    1994-01-01

    The phenomenon of repetition blindness (RB) may reveal a new limitation on human perceptual processing. Recently, however, researchers have attributed RB to post-perceptual processes such as memory retrieval and/or reporting biases. The standard rapid serial visual presentation (RSVP) paradigm used in most RB studies is, indeed, open to such objections. Here we investigate RB using a "single-frame" paradigm introduced by Johnston and Hale (1984) in which memory demands are minimal. Subjects made only a single judgement about whether one masked target word was the same or different than a post-target probe. Confidence ratings permitted use of signal detection methods to assess sensitivity and bias effects. In the critical condition for RB a precue of the post-target word was provided prior to the target stimulus (identity precue), so that the required judgement amounted to whether the target did or did not repeat the precue word. In control treatments, the precue was either an unrelated word or a dummy.

  2. Efficacy of topical 10% urea-based lotion in patients with ichthyosis vulgaris: a two-center, randomized, controlled, single-blind, right-vs.-left study in comparison with standard glycerol-based emollient cream.

    Science.gov (United States)

    Tadini, Gianluca; Giustini, Sandra; Milani, Massimo

    2011-12-01

    Ichthyoses are genetic disorders of keratinization which are uncomfortable due to their conspicuous scaling, itching and cosmetic problems. Ichthyoses can lead to social discrimination and psychological problems. Ichthyosis vulgaris (IV) is the most common form of these geno-dermatoses. IV is a chronic disorder that often requires continuous therapy. Emollient and keratolytic products are the mainstay treatments of IV. It is important that efficient, safe and well tolerated therapies should be available. Direct comparative data regarding efficacy of different emollient products in IV patients are very few. The aim of the study was to investigate the keratolytic and moisturizing properties as well as the tolerance of a new urea topical formulation (Ureadin Rx10) when applied to hyperkeratotic and dry skin in patients with (IV) in comparison with a standard emollient cream. The study was conducted as a two-center, randomized, controlled, single-blind, intra-patient (right-vs.-left) trial design. A total of 30 patients with IV between 8 and 65 (mean age: 25 years) treated with a 10% urea-based lotion, Ureadin Rx 10 * *Ureadin RX 10 is a registered trade name of ISDIN, Spain. (URx), for 4 weeks or a glycerol-based emollient cream, Dexeryl † †Dexeryl is a registered trade name of Pierre Fabre Dermatologie. (DC), in a right-vs.-left study design. Primary outcome was a 5-point SRRC Index score (evaluating scaling roughness, redness and cracks) evaluated at baseline and after 2 and 4 weeks of treatment. As secondary endpoints patients evaluated also the global efficacy (GE) and global tolerability (GT) scores with the help of a 10 cm visual analogue scale (0 = no efficacy at all/very bad tolerability; 10: excellent efficacy/excellent tolerability). At baseline the mean (SD) SRRC score was 9.5 (1.9) in the URx treated sites and 9.5 (1.9) in the DC treated sites. A total of 27 patients (90%) concluded the study period. Three patients were withdrawn prematurely

  3. 一种基于量子超密编码的代理盲签名方案的研究%Research on a Proxy Blind Signature Scheme Based on Quantum Superdense Coding

    Institute of Scientific and Technical Information of China (English)

    王辉; 石润华; 仲红; 汪开婷

    2016-01-01

    Proxy blind signature is widely applied to electronic voting, electronic commerce, and other network settings, etc. Combined with the situation of electronic bank payment, considering the correlative factors of the communication cost, the quantum operation complexity, and the veriifcation efficiency, etc, the paper proposes a proxy blind signature scheme based on the single particle superdense coding to blind the classical double bits information. The principle of the scheme is that the classical bit information is transmitted to the quantum system using the measurement of single particle in different measurement bases, in which the owner of the message blinds the secret message first and then the proxy signer signs the blinded message after authorized. Under the situation of without considering the particles detection, compared with other current well-known schemes, the biggest advantage of the scheme is to save half of the particles at least. In addition, signature party only needs to measure single particle and the length of the signature is appropriate.The verification party only needs to verify by contrast, and not needs to carry out the particle operation. The efifciencies of the signature ,veriifcation and communication are all improved.%代理盲签名在电子投票系统、电子商务系统和网络环境等方面有着广泛的应用。文章结合当下电子银行支付的情况,综合考虑现实情形下的通信开销、量子操作复杂性、验证效率等相关因素,首次提出一种基于单粒子超密编码来盲化经典双比特信息的量子代理盲签名方案。该方案原理是利用单粒子在不同测量基下的测量,将经典比特信息传送到量子系统中。消息拥有者先将秘密盲化,代理签名者在经过授权后对盲化消息进行有效签名。与现今其他主流方案相比,该方案最大的优势是使用的量子资源大大减少,在不考虑检测粒子的情形下,至少节

  4. The first rapid assessment of avoidable blindness (RAAB in Thailand.

    Directory of Open Access Journals (Sweden)

    Saichin Isipradit

    Full Text Available BACKGROUND: The majority of vision loss is preventable or treatable. Population surveys are crucial for planning, implementation, and monitoring policies and interventions to eliminate avoidable blindness and visual impairments. This is the first rapid assessment of avoidable blindness (RAAB study in Thailand. METHODS: A cross-sectional study of a population in Thailand age 50 years old or over aimed to assess the prevalence and causes of blindness and visual impairments. Using the Thailand National Census 2010 as the sampling frame, a stratified four-stage cluster sampling based on a probability proportional to size was conducted in 176 enumeration areas from 11 provinces. Participants received comprehensive eye examination by ophthalmologists. RESULTS: The age and sex adjusted prevalence of blindness (presenting visual acuity (VA <20/400, severe visual impairment (VA <20/200 but ≥20/400, and moderate visual impairment (VA <20/70 but ≥20/200 were 0.6% (95% CI: 0.5-0.8, 1.3% (95% CI: 1.0-1.6, 12.6% (95% CI: 10.8-14.5. There was no significant difference among the four regions of Thailand. Cataract was the main cause of vision loss accounted for 69.7% of blindness. Cataract surgical coverage in persons was 95.1% for cut off VA of 20/400. Refractive errors, diabetic retinopathy, glaucoma, and corneal opacities were responsible for 6.0%, 5.1%, 4.0%, and 2.0% of blindness respectively. CONCLUSION: Thailand is on track to achieve the goal of VISION 2020. However, there is still much room for improvement. Policy refinements and innovative interventions are recommended to alleviate blindness and visual impairments especially regarding the backlog of blinding cataract, management of non-communicative, chronic, age-related eye diseases such as glaucoma, age-related macular degeneration, and diabetic retinopathy, prevention of childhood blindness, and establishment of a robust eye health information system.

  5. Simple pendulum for blind students

    Science.gov (United States)

    Goncalves, A. M. B.; Cena, C. R.; Alves, D. C. B.; Errobidart, N. C. G.; Jardim, M. I. A.; Queiros, W. P.

    2017-09-01

    Faced with the need to teach physics to the visually impaired, in this paper we propose a way to demonstrate the dependence of distance and time in a pendulum experiment to blind students. The periodic oscillation of the pendulum is translated, by an Arduino and an ultrasonic sensor, in a periodic variation of frequency in a speaker. The main advantage of this proposal is the possibility that a blind student understands the movement without necessity of touching it.

  6. Experimental Demonstration of Blind Quantum Computing

    CERN Document Server

    Barz, Stefanie; Broadbent, Anne; Fitzsimons, Joseph F; Zeilinger, Anton; Walther, Philip

    2011-01-01

    Quantum computers, besides offering substantial computational speedups, are also expected to provide the possibility of preserving the privacy of a computation. Here we show the first such experimental demonstration of blind quantum computation where 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. We demonstrate various blind delegated computations, including one- and two-qubit gates and the Deutsch and Grover algorithms. Remarkably, the client only needs to be able to prepare and transmit individual photonic qubits. Our demonstration is crucial for future 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.

  7. Sensing Structures Inspired by Blind Cave Fish

    Science.gov (United States)

    McConney, Michael E.; Chen, Nannan; Lu, David; Anderson, Kyle D.; Hu, Huan; Liu, Chang; Tsukruk, Vladimir V.

    2009-03-01

    Blind cave fish, with degenerated non-functioning eyes, have evolved to ``see'' their hydrodynamic environment by using the flow receptors of the lateral line system. The hair-cell receptors are encapsulated in a hydrogel-like material, called a cupula, which increases the sensitivity of the hair-cell receptors by coupling their motion to the surrounding flowing media. We characterized the viscoelastic properties and of blind cave fish cupulae by using colloidal-probe spectroscopy in fluid. A photo-patternable hydrogel with similar properties was developed to mimic the fish receptor coupling structure. Flow-based measurements indicated that the hydrogels enhance drag through increased surface area, but also inherent material properties. These bio-inspired structures endowed micro-fabricated flow sensors with sensitivities rivaling that of fish.

  8. Latent Images, Blind Comments on Photography

    Directory of Open Access Journals (Sweden)

    Jenny Feray

    2013-12-01

    Full Text Available Photographs, or images as the final result of a process, merely mark out the moment when the eye is helplessly limited to what it sees. Thus, what escapes the eye in the physical sense, i.e. what the eye will never see, is what occurs before the product- image, within the act itself. The latent image, the desire-image, unfolds throughout the duration of the photographic act. When the picture is ‘taken’, then the desire subsides until the next desire for another image arises. Based on the photographic experiment by Jerry Chan, member of a group of blind people, this article aims at rethinking the photographic act as the real- life experience of an impression process, leading the blind apprentice photographer to experience sightedness within his very flesh.  

  9. 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....

  10. What It's Like to Be Color Blind

    Science.gov (United States)

    ... los dientes Video: Getting an X-ray 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 ...

  11. Reporting on blinding in trial protocols and corresponding publications was often inadequate but rarely contradictory

    DEFF Research Database (Denmark)

    Hróbjartsson, Asbjørn; Pildal, Julie; Chan, An-Wen

    2009-01-01

    OBJECTIVE: To compare the reporting on blinding in protocols and articles describing randomized controlled trials. STUDY DESIGN AND SETTING: We studied 73 protocols of trials approved by the scientific/ethical committees for Copenhagen and Frederiksberg, 1994 and 1995, and their corresponding...... publications. RESULTS: Three out of 73 trials (4%) reported blinding in the protocol that contradicted that in the publication (e.g., "open" vs. "double blind"). The proportion of "double-blind" trials with a clear description of the blinding of participants increased from 11 out of 58 (19%) when based...... on publications alone to 39 (67%) when adding the information in the protocol. The similar proportions for the blinding of health care providers were 2 (3%) and 22 (38%); and for the blinding of data collectors, they were 8 (14%) and 14 (24%). In 52 of 58 publications (90%), it was unclear whether all patients...

  12. Blindness in children: a worldwide perspective

    Directory of Open Access Journals (Sweden)

    Clare Gilber

    2007-06-01

    Full Text Available Many of the causes of childhood blindness are avoidable, being either preventable or treatable. Only three per cent of the world's blind population are children. However, because children have a lifetime of blindness ahead of them, the number of ‘blind person years’ resulting from blindness starting in childhood is second only to cataract. Controlling blindness in children is a priority of VISION 20203,4; however, as its causes differ from that of blindness in adults, different strategies, personnel, infrastructure, and equipment are required to combat it. There is also a greater urgency when managing children, as delays in treatment can lead to amblyopia (lazy eye.

  13. Effectiveness and tissue compatibility of a 12-week treatment of chronic venous leg ulcers with an octenidine based antiseptic--a randomized, double-blind controlled study.

    Science.gov (United States)

    Vanscheidt, Wolfgang; Harding, Keith; Téot, Luc; Siebert, Jörg

    2012-06-01

    The aim of this study was to evaluate the cytotoxic effect of octenidine dihydrochloride/phenoxyethanol (OHP) found in vitro by conducting a randomized, double-blind controlled clinical study focusing on its safe and effective use in chronic venous leg ulcers. In total, 126 male and female patients were treated with either OHP (n = 60) or Ringer solution (n = 66). The treatment lasted over a period of maximum 12 weeks. For the assessment of the wound-healing process, clinical outcome parameters were employed, that is, time span until 100% epithelization, wound status and the wound surface area were analysed. Side effects were recorded during the study period. The median time to complete ulcer healing was comparable between the OHP and Ringer solution groups (92 versus 87 days; P = 0·952), without being influenced by wound size or duration of the target ulcer (P-values: 0·947/0·978). In patients treated with OHP, fewer adverse events (AEs) were observed compared with the Ringer group (17% versus 29% of patients reported 20 versus 38 AEs). OHP is well suitable for the treatment of chronic wounds without cytotoxic effects. Furthermore, OHP does not impair the wound healing in chronic venous ulcers. © 2011 The Authors. © 2011 Blackwell Publishing Ltd and Medicalhelplines.com Inc.

  14. Effective Electronic Voting Based on Blind Signature%基于盲签名的高效电子投票方案

    Institute of Scientific and Technical Information of China (English)

    李欣妍; 牟化建; 张韶华

    2014-01-01

    In the light of the part problems in literatures,an improved electronic voting scheme is put forward in the paper by combining elliptic curve crypto system and blind signature,and its security is analyzed.The results show that the program can prevent repudiation,forgery,tamper,and protect the legitimate rights and interests of the voters.It also has stronger robustness and practicality,which can meet the characteristics of an ideal electronic voting scheme.%针对已有文献设计方案的不足,结合椭圆曲线密码体制和盲签名,提出了改进的电子投票方案,并对其安全性进行分析。本方案采用椭圆曲线密码加密算法和盲签名等技术,防止抵赖、伪造、篡改,保护投票人的合法权益,具有更强的抗攻击性和实用性,满足理想的电子投票方案所具有的特征。

  15. [Educative game on drugs for blind individuals: development and assessment].

    Science.gov (United States)

    Mariano, Monaliza Ribeiro; Rebouças, Cristiana Brasil de Almeida; Pagliuca, Lorita Marlena Freitag

    2013-08-01

    Study aimed to develop and assess an educational game on psychoactive drugs accessible to blind individuals, conducted in three steps: development of the educative game, evaluation by three special education experts, and assessment by twelve blind individuals. As a result, a board game called Drugs: staying clean was developed. In the Alpha version, experts made suggestions regarding the game rules and instructions and the board base, including square texture, game pieces, and Braille writing. In Beta version, we proceeded to the assessment by the blind participants, who suggested changes in the square texture and the addition of Velcro-type material to fix the counters on the board. Then, the Gamma version was played by the last pairs of blind players and was considered by them to be adequate. In the evaluation of the experts, the game was appropriate, as it allowed access to information on psychoactive drugs in a ludic and playful manner.

  16. 基于代理盲签名的车载自组网认证技术研究%Research of a Authentication Scheme Based on the Proxy Blind Signature Scheme for the Vehicular Ad-hoc Networks

    Institute of Scientific and Technical Information of China (English)

    徐甜; 宋强

    2012-01-01

    研究了适用于移动车载自组织网络的基于代理盲签名方案的移动节点认证技术.针对移动车载自组网在大规模节点组网和节点移动时,认证复杂且效率低下的问题,提出一种基于代理多重签名和盲签名的认证技术.该技术采用代理签名方案适应车载节点的移动性,代理多重签名解决节点间重复认证问题,采用盲签名方案适应了车载网分布式系统的复杂性和实现了车载节点间认证的交互性,最后采用基于DSA变形的代理盲签名方案避免伪造攻击,并给出认证系统体系结构和安全签名密钥发布模型.实验分析表明,该技术能够较好地适应车载节点的移动性和复杂性,在车载网安全性和认证效率上具有良好的性能.%we proposed a signature scheme based on the proxy multi-signature and blind signature certification technology. This technology, using proxy signature scheme and mobility of vehicle—mounted node to proxy multi-signature solve between the nodes authentication problems, the repeated to blind signature scheme vehicle-mounted nets distributed system's complexity and realize the on—board authentication interactivity between the nodes, finally the agency based on DSA deformation to avoid blind signature scheme, and gives collusion attack authentication system structure and secure signature key release model. Experimental results showed that this technology can better meet the on-board node mobility and complexity, in the on-board nets safety and the authentication efficiency has good performance.

  17. Change of racial discrimination in the United States based on the film “Blind Side”%从影视文学作品透析美国种族歧视的变迁

    Institute of Scientific and Technical Information of China (English)

    贾晓霞

    2016-01-01

    The racial discrimination against blacks and other ethnic minorities in the United States has been abolished in the law, but in real life, it is still a sensitive issue in the United States. This paper analyzes and discusses current situation and changes of racial discrimination in the United States based on the movie“Blind Side”.%美国对黑人等少数民族的种族歧视虽已在法律上被废除,但在现实生活中却还是影响美国社会的敏感问题。本文通过电影文学作品《弱点》对美国种族歧视的变迁及现状展开分析与讨论。

  18. A NOVEL BLIND FIR CHANNEL ESTIMATION BASED ON GENETIC ALGORITHM%一种新的基于遗传算法的盲 FIR 信道估计

    Institute of Scientific and Technical Information of China (English)

    李成; 陈丰照

    2016-01-01

    为了改善盲有限脉冲响应 FIR(Finite Impulse Response)信道估计性能,提出基于高阶统计协同进化遗传算法的盲 FIR 信道估计方法。通过协同进化的方法来改善标准遗传算法的搜索机制,并给出利用累积量拟合不同累积量切片的代价函数,通过最小化代价函数来估计信道系数。同时为了提高收敛速度,采用了基于高阶统计量数学关系的初始种群。仿真结果表明,新算法的收敛速度和精度均优于加权片算法和标准遗传算法等经典算法,尤其是在高阶信道中。%In order to improve the performance of blind FIR channel estimation,we proposed a blind FIR channel estimation method which is based on coevolutionary genetic algorithm with higher order statistics.We improved the search mechanism of a simple genetic algorithm by using the coevolutionary method,and submitted a cost function in which we utilised the cumulant to fit different cumulant slices,and estimated the channel coefficients by minimising this cost function.Meanwhile,in order to improve convergence rate,we used initial population which is based on mathematical relationship in higher order statistics.Simulation results showed that the new scheme surpasses the classical methods such as weighted slice and simple genetic algorithm method in terms of convergence speed and accuracy especially when high-order channels are considered.

  19. Blind source separation of helicopter vibration signal based on improved particle swarm algorithm%基于改进粒子群算法的直升机振动信号盲分离

    Institute of Scientific and Technical Information of China (English)

    申江江; 高峰; 曲建岭; 袁涛; 刘锦涛

    2016-01-01

    振动信号分析是直升机状态监控的重要研究内容之一。针对某型直升机加装的振动信号采集系统,提出一种基于改进粒子群优化算法(PSO)的盲源分离方法。介绍了盲源分离(BSS)基本理论及改进的基于动态因子的粒子群优化算法,将二者结合应用于某型直升机振动信号盲分离研究。仿真实验及噪声中实测直升机振动信号的盲分离都取得了良好的分离效果,结果表明相比于直接使用FastICA方法,所提出的方法具有分离精度高、迭代次数少等优点。%Vibration signal analysis is one of significant research contents for helicopter condition monitoring. Aiming at the vibration signal acquisition system installed a helicopter,a blind source separation (BSS )method based on improved particle swarn optimization (PSO)is proposed.BSS basic theory and improved PSO based on dynamic factor are introduced,and they are combined and put into BSS research of helicopter vibration signal.The blind source separation of simulation experiment and real-acquainted helicopter vibration signals in noise environment obtains good separation result.And compared with using FastICA directly,the result shows that this algorithm proposed in this paper has advantages of high precision and less iteration times.

  20. 基于盲数的配电系统可靠性评估%Power distribution system reliability evaluation based on blind number

    Institute of Scientific and Technical Information of China (English)

    赵书强; 王海巍

    2011-01-01

    传统的配电系统可靠性评估将可靠性参数作为点值进行评估,但限于客观条件,可靠性参数具有不确定性,必然会导致可靠性评估不准确.通过分析配电网可靠性评估中的各种不确定性因素,研究合理描述和处理不确定性信息的方法,在对已有的处理不确定性问题方法研究的基础上,将盲数理论引入配电网可靠性评估中,利用盲数理论来描述和处理配电网可靠性评估中的不确定性信息,可提高配电系统可靠性评估的准确性.通过算例验证了方法的有效性.%Traditional power distribution system reliability evaluation takes the reliable parameter as point value to carry on the evaluation. But limited by the objective conditions, the reliable parameter has uncertainty, which will cause the inaccurate reliability evaluation. Through analyzing the various uncertainty factors in distribution network reliability evaluation, the methods to reasonably describe and process uncertainty information are researched. On the basis of the existing method in processing uncertainty question, this paper introduces blind number theory into distribution network power supply reliability evaluation, uses it to describe and process uncertainty information in distribution network reliability evaluation, and improves the accuracy of distribution system reliability evaluation. Through the example, the validity of the method is confirmed.

  1. High-performance ultraviolet detection and visible-blind photodetector based on Cu{sub 2}O/ZnO nanorods with poly-(N-vinylcarbazole) intermediate layer

    Energy Technology Data Exchange (ETDEWEB)

    Perng, Dung-Ching, E-mail: dcperng@ee.ncku.edu.tw [Institute of Microelectronics and Electrical Engineering Department, National Cheng Kung University, One University Road, Tainan 701, Taiwan (China); Center for Micro/Nano Science and Technology, National Cheng Kung University, One University Road, Tainan 701, Taiwan (China); Lin, Hsueh-Pin; Hong, Min-Hao [Institute of Microelectronics and Electrical Engineering Department, National Cheng Kung University, One University Road, Tainan 701, Taiwan (China)

    2015-12-14

    This study reports a high-performance hybrid ultraviolet (UV) photodetector with visible-blind sensitivity fabricated by inserting a poly-(N-vinylcarbazole) (PVK) intermediate layer between low-cost processed Cu{sub 2}O film and ZnO nanorods (NRs). The PVK layer acts as an electron-blocking/hole-transporting layer between the n-ZnO and p-Cu{sub 2}O films. The Cu{sub 2}O/PVK/ZnO NR photodetector exhibited a responsivity of 13.28 A/W at 360 nm, a high detectivity of 1.03 × 10{sup 13} Jones at a low bias of −0.1 V under a low UV light intensity of 24.9 μW/cm{sup 2}. The photo-to-dark current ratios of the photodetector with and without the PVK intermediate layer at a bias of −0.5 V are 1.34 × 10{sup 2} and 3.99, respectively. The UV-to-visible rejection ratios (R{sub 360 nm}/R{sub 450 nm}) are 350 and 1.735, respectively. Several features are demonstrated: (a) UV photo-generated holes at the ZnO NRs can effectively be transported through the PVK layer to the p-Cu{sub 2}O layer; (b) the insertion of a PVK buffer layer significantly minimizes the reverse-bias leakage current, which leads to a larger amplification of the photocurrent; and (c) the PVK buffer layer greatly improves the UV-to-visible responsivity ratio, allowing the device to achieve high UV detection sensitivity at a low bias voltage using a very low light intensity.

  2. Antioxidant Effects of a Hydroxytyrosol-Based Pharmaceutical Formulation on Body Composition, Metabolic State, and Gene Expression: A Randomized Double-Blinded, Placebo-Controlled Crossover Trial

    Directory of Open Access Journals (Sweden)

    Carmela Colica

    2017-01-01

    Full Text Available Hydroxytyrosol (HT plays a significant role in cardiovascular disease (CVD protection, and its metabolites are able to protect from the endothelial dysfunction commonly present in atherosclerosis. This randomized double-blinded, placebo-controlled crossover trial determined the effect in healthy volunteers of two gastroresistant capsules containing 15 mg/day of HT, for a 3-week period (HTT. Evaluation of nutritional status, serum metabolites, oxidative stress biomarkers, and gene expression of 9 genes related to oxidative stress, inflammation, and CVDs was performed. Oxidation biomarkers like thiol group (p=0.001, total antioxidant status (TAS (p=0.001, superoxide dismutase 1 (SOD1 (2−ΔΔCt = 3.7, and plasma concentration of HT (2.83 μg·mL−1 were significantly increased, while nitrite (p=0.001, nitrate (p=0.001, and malondialdehyde (MDA (p=0.02 were drastically reduced after HTT. A significant reduction of body fat mass percentage (p=0.01, suprailiac skinfold (p=0.01, and weight (p=0.04; Δ% = −0.46% was observed after HTT. This study shows that regular intake of 15 mg/day of HT changed body composition parameters and modulated the antioxidant profile and the expression of inflammation and oxidative stress-related genes. However, it is advisable to personalize HT doses in order to exert its health benefits in CVD prevention and protection of LDL-C particles from oxidative damage. This trial is registered with ClinicalTrials.gov NCT01890070.

  3. 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.

  4. Static analysis for blinding

    DEFF Research Database (Denmark)

    Nielsen, Christoffer Rosenkilde; Nielson, Hanne Riis

    2006-01-01

    The classical key distribution protocols are based on symmetric and asymmetric encryption as well as digital signatures. Protocols with different purposes often requires different cryptographic primitives, an example is electronic voting protocols which are often based on the cryptographic...

  5. 基于时频分析的多目标盲波束形成算法∗%A blind b eamforming algorithm for multitarget signals based on time-frequency analysis

    Institute of Scientific and Technical Information of China (English)

    刘亚奇; 刘成城; 赵拥军; 朱健东

    2015-01-01

    The existing blind beamforming methods are effective only under the condition that the source signals have some special statistical or structural characteristics. Additionally, the structure of cascade model is complicated and the stability of parallel model is poor when dealing with multi-target signals. To address these problems, a novel blind beamforming algorithm for multi-target signals based on time-frequency (TF) analysis is proposed in this paper. The received array signals are first transformed into time-frequency domain by using quadratic time-frequency distributions (TFDs). Then, the single-source auto-term TF points which show energy concentration at a single signal are extracted through three operations: (i) removing noise points by setting a reasonable threshold, (ii) separating auto-term TF points from cross-term points, and (iii) selecting the single-source auto-term TF points from the auto-term ones. Moreover, these single-source auto-term TF points are classified by the principal eigenvector of their spatial time-frequency distribution matrixes. For each class of TF points, the uncertain set of signal steering vector is given, whose radius is defined as the ultimate range between the center and the elements in the class. Within the uncertain set, an optimization algorithm is provided to get the optimal estimation of the signal steering vector. Finally, the blind beamforming for multi-target signals is achieved based on the Capon method, which can enhance the desired signals and suppress the noise and interference signals. In addition, the influence of parameters selection, the clustering method of unknown source number, and the computational complexity of the proposed algorithm are analyzed. The proposed algorithm can achieve parallel output of multi-target signals under the condition that the array manifold and the direction of arrival (DOA) are unknown. Also, the complex iterative solving processing may be avoided and special limitations on

  6. Virtual environment interaction through 3D audio by blind children.

    Science.gov (United States)

    Sánchez, J; Lumbreras, M

    1999-01-01

    Interactive software is actively used for learning, cognition, and entertainment purposes. Educational entertainment software is not very popular among blind children because most computer games and electronic toys have interfaces that are only accessible through visual cues. This work applies the concept of interactive hyperstories to blind children. Hyperstories are implemented in a 3D acoustic virtual world. In past studies we have conceptualized a model to design hyperstories. This study illustrates the feasibility of the model. It also provides an introduction to researchers to the field of entertainment software for blind children. As a result, we have designed and field tested AudioDoom, a virtual environment interacted through 3D Audio by blind children. AudioDoom is also a software that enables testing nontrivial interfaces and cognitive tasks with blind children. We explored the construction of cognitive spatial structures in the minds of blind children through audio-based entertainment and spatial sound navigable experiences. Children playing AudioDoom were exposed to first person experiences by exploring highly interactive virtual worlds through the use of 3D aural representations of the space. This experience was structured in several cognitive tasks where they had to build concrete models of their spatial representations constructed through the interaction with AudioDoom by using Legotrade mark blocks. We analyze our preliminary results after testing AudioDoom with Chilean children from a school for blind children. We discuss issues such as interactivity in software without visual cues, the representation of spatial sound navigable experiences, and entertainment software such as computer games for blind children. We also evaluate the feasibility to construct virtual environments through the design of dynamic learning materials with audio cues.

  7. 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....

  8. Design of ATmega8-based infrared guidance system for the blind%基于ATmega8单片机的红外导盲系统设计

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    An infrared blind guidance system with single chip microcomputer was designed for helping blind people. The system uses ATmega8 as control core and chooses the ranging infrared sensor GP2Y0A02YK0F based on PSD principle. The sin⁃glechip samples the output analog signals from distance measuring sensors through ADC ports,and uses moving average filter to eliminate noise interference. The singlechip compares the distance value to the threshold value,and controls the voice broadcast⁃ing circuit to announce the distance reminding messages. The system detects the barriers from three directions including front, left and right within 1.5 meters,and it has strong anti⁃interference and stability.%  为帮助盲人群体更方便地导盲,设计了用单片机控制的红外导盲系统。以ATmega8单片机为控制核心,选用基于PSD原理的红外测距传感器GP2Y0A02YK0F。单片机利用ADC端口实时采集测距传感器的模拟输出信号,并对采集到的数据进行滑动平均滤波,以消除噪声干扰。单片机将得到的距离值与门限值进行比较,并控制语音播报电路发出距离提示信息。该系统能检测前、左、右3个方向1.5 m内的障碍物信息,抗干扰性强,稳定可靠。

  9. Adaptive color blind watermarking algorithm based on complex encrypting and DCT transform%基于复合加密的自适应DCT域盲检彩色水印算法

    Institute of Scientific and Technical Information of China (English)

    刘志军; 刘春立

    2012-01-01

    A kind of complex encrypting adaptive color blind watermarking algorithm was proposed based on timedomain and frequencydomain(integer wavelets domaion).Pixel value was displaced by logistic chaotic mapping and Chebychev chaotic mapping to creat the complex chaotic sequence.Pixel position was scrambled by Arnold transform.The watermarking embedding intensity factor was counted by the DCT coefficient.A color watermarking embedding and blind extracting algorithm was designed.Algorithm experiments were produced by Matlab7.Experimental results showed that the algorithm had good transparency and strong robustness on the common watermarking attack.%提出了一种基于时域和频域(整数小波域)复合加密自适应彩色水印算法,采用Logistic混沌映射和Cheby-chev混沌映射生成复合混沌序列置换像素的值,Arnold变换置乱像素的位置,并根据离散余弦变换(discrete cosinetransform,DCT)系数计算水印嵌入强度因子,设计了彩色水印的嵌入与盲检提取算法。利用Matlab7.0平台验证了该算法,实验结果表明:该算法对常见的水印攻击不仅具有较好的透明性,而且具有较强的鲁棒性。

  10. Catheter-based donor site analgesia after rib grafting: a prospective, randomized, double-blinded clinical trial comparing ropivacaine and bupivacaine.

    Science.gov (United States)

    Anantanarayanan, Parameswaran; Raja, Dharmesh Kumar; Kumar, J Naveen; Sneha, P; Christabel, Amelia; Manikandhan, Ramanathan; Elavazhagan, Namasivayam

    2013-01-01

    Although ribs provide the best source of cartilage for reconstruction, its harvesting is associated with significant postoperative pain and sometimes incapacitating functional deficit. The lack of studies in the maxillofacial literature on regional analgesia for rib harvests stimulated this study design. This study compared ropivacaine with bupivacaine in providing postoperative analgesia after rib harvest. Patients who needed rib grafting for maxillofacial reconstructive procedures were enrolled in this prospective, randomized, double-blinded clinical trial. Patients were randomly allocated to 1 of 2 groups with different modalities of anesthesia against a control group. A catheter was embedded in the rib donor site in all patients. Patients in group A received 0.75% ropivacaine, those in group B received 0.5% bupivacaine, and those in croup C patients received normal saline and served as the controls. The outcome variables were the subjective and objective pain scores, the duration of action, and the efficacy of the drugs after rib harvest. Dependent variables were the need for a rescue analgesic by the patient and the duration of hospital stay. The subjective intensity of pain at rest was calculated using the visual analog scale. The objective pain scores at function were evaluated by comparing preoperative with postoperative values of incentive spirometry, breath-holding test, maximal chest expansion, and match-blowing test. The t test and paired samples test were used to the analyze data, and a P value less than .05 was considered significant. Forty-two patients were enrolled in this study. Patients in groups A and B showed significant pain relief compared with group C. Patients in group A showed significantly less pain at rest (2.8±0.894) compared with those in group B (3.7±0.875; Ppain at function (3.8±0.894) compared with those in group B (4.7±0.923; Prib harvesting provides excellent postoperative comfort, with ropivacaine providing an earlier return

  11. Effects of Pilates-Based Core Stability Training in Ambulant People With Multiple Sclerosis: Multicenter, Assessor-Blinded, Randomized Controlled Trial.

    Science.gov (United States)

    Fox, Esther E; Hough, Alan D; Creanor, Siobhan; Gear, Margaret; Freeman, Jennifer A

    2016-08-01

    Pilates exercise is often undertaken by people with multiple sclerosis (MS) who have balance and mobility difficulties. The primary aim of the study was to compare the effects of 12 weeks of Pilates exercises with relaxation on balance and mobility. Secondary aims were: (1) to compare standardized exercises with relaxation and (2) to compare Pilates exercises with standardized exercises. A multicenter, assessor-blinded, randomized controlled trial was conducted. Participants with Expanded Disability Status Scale scores of 4.0 to 6.5 were randomly allocated to groups receiving 12 weeks of Pilates exercises, standardized exercises, or relaxation. Assessments were undertaken at baseline and weeks 12 and 16 (primary outcome measure: 10-Meter Timed Walk Test [10MTW]). One hundred participants (mean age=54 years, 74% female) were randomized to study groups. Six participants relapsed (withdrew from the study), leaving 94 participants for intention-to-treat analysis. There was no significant difference in mean 10MTW measurements between the Pilates and relaxation groups. At 12 weeks, there was a mean reduction of 4.2 seconds for the standardized exercise group compared with the relaxation group (95% confidence interval [relaxation group minus standardized exercise group measurements]=0.0, 8.4) and a mean reduction of 3.7 seconds for the Pilates group compared with the standardized exercise group (95% confidence interval [Pilates group minus standardized exercise group measurements]=-0.4 to 7.8). At 16 weeks, mean 10MTW times for the standardized exercise group remained quicker than those for the Pilates and relaxation groups, although the differences were nonsignificant. There were no significant differences between the Pilates and relaxation groups for any secondary outcome measure. In this study, therapists were limited to a standardized basket of exercises that may have affected the study outcomes. Furthermore, choosing measures such as posturography to assess balance

  12. Addition of sub-anaesthetic dose of ketamine reduces gag reflex during propofol based sedation for upper gastrointestinal endoscopy: A prospective randomised double-blind study

    Directory of Open Access Journals (Sweden)

    Manish Tandon

    2014-01-01

    Full Text Available Background and Aims: Gag reflex is unwanted during upper gastrointestinal endoscopy (UGIE. Experimental studies have demonstrated that N-methyl-D-aspartate receptor antagonism prevents gag reflex. We conducted a study to determine if sub-anaesthetic doses of ketamine, added to propofol, reduce the incidence of gag reflex. Methods: This prospective, randomised, double-blind and placebo-controlled study was done in a tertiary care hospital. A total of 270 patients undergoing UGIE, were randomised to propofol (P group (n = 135 or propofol plus ketamine (PK group (n = 135. All patients received propofol boluses titrated to Ramsay sedation score of not <4. Patients in PK group in addition received ketamine, 0.15 mg/kg immediately before the first-propofol dose. Top-up doses of propofol were given as required. Stata 11 software (StataCorp. was used to calculate the proportion of patients with gag reflex and the corresponding relative risk. Propofol consumed and time to recovery in the two groups was compared using Student′s t-test and Cox proportional hazards regression respectively. Results: Significantly, fewer patients in the PK group had gag reflex compared to the P group (3 vs. 23, risk ratio = 0.214, 95% confidence interval [CI], 0.07-0.62; P = 0.005. The incidence of hypotension (6 vs. 16, risk ratio = 0.519, 95% CI = 0.25-1.038; P = 0.06, number of required airway manoeuvres (4 vs. 19, risk ratio = 0.32, 95% CI = 0.13-0.74; P = 0.014, median time to recovery (4 min vs. 5 min, hazard ratio = 1.311, 95% CI = 1.029-1.671; P = 0.028 and propofol dose administered (152 mg vs. 167 mg, 95% CI = 4.74-24.55; P = 0.004 was also less in the PK group compared to the P group. Conclusion: Ketamine in sub-anaesthetic dose decreases gag reflex during UGIE.

  13. Sulfadoxine-pyrimethamine-based combinations for malaria: a randomised blinded trial to compare efficacy, safety and selection of resistance in Malawi.

    Directory of Open Access Journals (Sweden)

    David J Bell

    Full Text Available BACKGROUND: In Malawi, there has been a return of Plasmodium falciparum sensitivity to chloroquine (CQ since sulfadoxine-pyrimethamine (SP replaced CQ as first line treatment for uncomplicated malaria. When used for prophylaxis, Amodiaquine (AQ was associated with agranulocytosis but is considered safe for treatment and is increasingly being used in Africa. Here we compare the efficacy, safety and selection of resistance using SP or CQ+SP or artesunate (ART+SP or AQ+SP for the treatment of uncomplicated falciparum malaria. METHODOLOGY AND FINDINGS: 455 children aged 1-5 years were recruited into a double-blinded randomised trial comparing SP to the three combination therapies. Using intention to treat analysis with missing outcomes treated as successes, and without adjustment to distinguish recrudescence from new infections, the day 28 adequate clinical and parasitological response (ACPR rate for SP was 25%, inferior to each of the three combination therapies (p<0.001. AQ+SP had an ACPR rate of 97%, higher than CQ+SP (81% and ART+SP (70%, p<0.001. Nineteen children developed a neutropenia of

  14. Computer Reader for the Blind

    Science.gov (United States)

    1990-01-01

    Optacon II uses the same basic technique of converting printed information into a tactile image as did Optacon. Optacon II can also be connected directly to a personal computer, which opens up a new range of job opportunities for the blind. Optacon II is not limited to reading printed words, it can convert any graphic image viewed by the camera. Optacon II demands extensive training for blind operators. TSI provides 60-hour training courses at its Mountain View headquarters and at training centers around the world. TeleSensory discontinued production of the Optacon as of December 1996.

  15. 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.

  16. The spatiotopic 'visual' cortex of the blind

    Science.gov (United States)

    Likova, Lora

    2012-03-01

    Visual cortex activity in the blind has been shown in sensory tasks. Can it be activated in memory tasks? If so, are inherent features of its organization meaningfully employed? Our recent results in short-term blindfolded subjects imply that human primary visual cortex (V1) may operate as a modality-independent 'sketchpad' for working memory (Likova, 2010a). Interestingly, the spread of the V1 activation approximately corresponded to the spatial extent of the images in terms of their angle of projection to the subject. We now raise the questions of whether under long-term visual deprivation V1 is also employed in non-visual memory task, in particular in congenitally blind individuals, who have never had visual stimulation to guide the development of the visual area organization, and whether such spatial organization is still valid for the same paradigm that was used in blindfolded individuals. The outcome has implications for an emerging reconceptualization of the principles of brain architecture and its reorganization under sensory deprivation. Methods: We used a novel fMRI drawing paradigm in congenitally and late-onset blind, compared with sighted and blindfolded subjects in three conditions of 20s duration, separated by 20s rest-intervals, (i) Tactile Exploration: raised-line images explored and memorized; (ii) Tactile Memory Drawing: drawing the explored image from memory; (iii) Scribble: mindless drawing movements with no memory component. Results and Conclusions: V1 was strongly activated for Tactile Memory Drawing and Tactile Exploration in these totally blind subjects. Remarkably, after training, even in the memory task, the mapping of V1 activation largely corresponded to the angular projection of the tactile stimuli relative to the ego-center (i.e., the effective visual angle at the head); beyond this projective boundary, peripheral V1 signals were dramatically reduced or even suppressed. The matching extent of the activation in the congenitally blind

  17. Blind separation of multicomponent seismic wavefield using SVD of reduced dimension spectral matrix

    OpenAIRE

    2017-01-01

    This paper presents a blind separation algorithm based on singular value decomposition (SVD) of reduced dimension spectral matrix. Furthermore, a mathematical matrix model of the multicomponent seismic wavefield is developed as a framework for implementing the proposed algorithm. The proposed blind separation algorithm organizes the frequency transformed multicomponent seismic wavefield into one long data vector. The blind separation of the desired seismic wavefield is accomplished by project...

  18. Remarks on certain new methods for blind identification of FIR channels

    OpenAIRE

    P. P. Vaidyanathan; Su, Borching

    2004-01-01

    This paper discusses a number of issues pertaining to blind identification of channels. The basics of blind identification are first discussed and a method called Vandermonde method is presented which is based on elementary linear system principles. Then some remarks are made about precoders with paraunitary antipodal preprocessors. It is argued that such preprocessors usually destroy signal richness which is a necessary feature in blind identification systems.

  19. 基于DCT和DFT视频盲水印算法的研究与实现%Research and Implementation on Blind Video Watermarking Algorithms Based on DCT and DFT

    Institute of Scientific and Technical Information of China (English)

    丁海洋

    2012-01-01

    为了统计不同算法的透明性和鲁棒性,比较不同算法的优缺点,针对基于DCT和DFT的视频盲水印算法进行了研究。研究并实现了3种基于DCT的视频水印算法和1种基于DFT的视频水印算法。通过实验,统计它们的透明性和鲁棒性。结果表明,DCT算法的透明性优于DFT算法;DFT算法抗几何攻击的鲁棒性优于DCT算法,DCT算法抗编码攻击的鲁棒性优于DFT算法。%Video watermark is an emerging technology for copyright protection and authentication of digital video, this paper has researched and realized blind video watermarking algorithms based on DCT and DFT, Studied and implemented three kinds of DCT-based video watermark algorithms and one DFT-based video watermark algorithm, and counted transparency and robustness of algorithms. Experiments show that the transparency of DCT algorithms is superior to the DFT algorithm; and the robustness of the DFT algorithm against ge- ometrical attacks is better than DCT algorithms, the robustness of DCT algorithms against coding attacks is better than the DFT algorithm.

  20. Prevalence and causes of low vision and blindness worldwide

    Directory of Open Access Journals (Sweden)

    A.O . Oduntan

    2005-01-01

    Full Text Available A recent review of the causes and prevalence of low vision and blindness world wide is lack-ing. Such review is important for highlighting the causes and prevalence of visual impairment in the different parts of the world. Also, it is important in providing information on the types and magnitude of eye care programs needed in different parts of the world. In this article, the causes and prevalence of low vision and blind-ness in different parts of the world are reviewed and  the  socio-economic  and  psychological implications are briefly discussed. The review is based on an extensive review of the litera-ture using computer data bases combined with review of available national, regional and inter-national journals. Low vision and blindness are more prevalent in the developing countries than in the developed ones. Generally, the causes and prevalence of the conditions vary widely in different parts of the world and even within the same country. World wide, cataract is the most common cause of blindness and low vision among adults and elderly. Infectious diseases such as trachoma and onchocerciasis result-ing in low vision and blindness are peculiar to Africa, Asia and South America. Hereditary and congenital conditions are the most common causes of low vision and blindness among chil-dren worldwide.

  1. The Blind Learning Aptitude Test.

    Science.gov (United States)

    Newland, T. Ernest

    A Blind Learning Aptitude Test (BLAT) was developed on the basis of sense of touch rather than on conventional experience, fine sensory discrimination, or verbal competency. From a pool of about 350 items, most of them used in testing intelligence in the sighted, a pool of 94 was selected and embossed after the manner of braille. A residual pool…

  2. Ask a Scientist: What is Color Blindness?

    Medline Plus

    Full Text Available ... video series. Dr. Sheldon Miller answers questions about color blindness, whether it can be treated, and how people ... an optical illusion? Click to Watch What is color blindness? Click to Watch How do I become a ...

  3. 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...

  4. 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.

  5. 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.

  6. Ask a Scientist: What is Color Blindness?

    Medline Plus

    Full Text Available ... Illusions Printables Ask a Scientist Video Series Why can’t you see colors well in the dark? ... Miller answers questions about color blindness, whether it can be treated, and how people become color blind. ...

  7. Poverty and blindness in Africa.

    Science.gov (United States)

    Naidoo, Kovin

    2007-11-01

    Africa carries a disproportionate responsibility in terms of blindness and visual impairment. With approximately 10 per cent of the world's population, Africa has 19 per cent of the world's blindness. It is no surprise that this reality also mirrors the situation in terms of the burden of world poverty. There is an increasing recognition of the need to highlight the link between poverty, development and health care. Blindness, disabling visual impairment and the overall lack of eye-care services are too often the result of social, economic and developmental challenges of the developing world. The state of eye care in Africa stands in alarming contrast to that in the rest of the world. Poor practitioner-to-patient ratios, absence of eye-care personnel, inadequate facilities, poor state funding and a lack of educational programs are the hallmarks of eye care in Africa, with preventable and treatable conditions being the leading cause of blindness. Eye diseases causing preventable blindness are often the result of a combination of factors such as poverty, lack of education and inadequate health-care services. The challenge that Vision 2020 has set itself in Africa is enormous. Africa is not a homogenous entity, the inter- and intra-country differences in economic development, prevalence of disease, delivery infrastructure and human resources amplify the challenges of meeting eye-care needs. The successful implementation of Vision 2020 programs will be hindered without the development of a comprehensive, co-ordinated strategy that is cognisant of the differences that exist and the need for comprehensive solutions that are rooted in the economic and political realities of the continent as well as the individual countries and regions within countries. This strategy should recognise the need for economic growth that results in greater state funded eye-care services that focus on health promotion to ensure the prevention of eye disease, the development of eye clinics in

  8. Effects of Game-Based Constraint-Induced Movement Therapy on Balance in Patients with Stroke: A Single-Blind Randomized Controlled Trial.

    Science.gov (United States)

    Choi, Ho-Suk; Shin, Won-Seob; Bang, Dae-Hyouk; Choi, Sung-Jin

    2017-03-01

    The aims of this work were to determine whether game-based constraint-induced movement therapy (CIMT) is effective at improving balance ability in patients with stroke, and to provide clinical knowledge of game-based training that allows application of CIMT to the lower extremities. Thirty-six patients with chronic stroke were randomly assigned to game-based CIMT (n = 12), general game-based training (n = 12), and conventional (n = 12) groups. All interventions were conducted 3 times a week for 4 weeks. The static balance control and weight-bearing symmetry were assessed, and the Functional Reach Test (FRT), modified Functional Reach Test (mFRT), and Timed Up and Go (TUG) test were performed to evaluate balance ability. All 3 groups showed significant improvement in anterior-posterior axis (AP-axis) distance, sway area, weight-bearing symmetry, FRT, mFRT, and TUG test after the intervention (P game-based CIMT group compared with the other group (P game-based training and the game-based CIMT both improved on static and dynamic balance ability, game-based CIMT had a larger effect on static balance control, weight-bearing symmetry, and side-to-side weight shift.

  9. Association Between Retinal Vascular Calibre and Blindness in Young Patients With Type 1 Diabetes

    DEFF Research Database (Denmark)

    Rasmussen, Malin Lundberg

    Association Between Retinal Vascular Calibre and Blindness in Young Patients With Type 1 Diabetes Purpose To examine the association between retinal vascular calibre and incident blindness caused by diabetic retinopathy in young patients with type 1 diabetes. Methods A case-control study of 6...... patients (12 eyes) who later went blind and 18 age- and sex-matched controls (36 eyes). They were all identified in a population-based cohort study of 339 patients with type 1 diabetes. Patients and controls all participated in a clinical baseline examination in 1995 and were subsequently followed for 15...... years. Incident blindness was defined for patients who registered between 1995 and 2010 in the Danish Association of the Blind, which is a voluntary organization open for patients with a visual acuity at or below 6/60 (0.1) in the best eye. Each blind patient was matched with 3 controls regarding age...

  10. 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...

  11. Blinding trachoma among refugees:complicating social disaster

    Institute of Scientific and Technical Information of China (English)

    Yeshigeta; Gelaw; Aemero; Abateneh

    2015-01-01

    Objective:To determine the prevalence of blinding trachoma among refugees in South Western Ethiopia.Methods:A cross-sectional outreach clinic based descriptive study was conducted on 1054 refugees in Southwest Ethiopia.A basic eyelid and cornea examination for signs of trachoma was done by using 2.5× binocular magnifying loupe.The findings were classified by using the World Health Digitization simplified trachoma grading system and data were analyzed by using SPSS version 16.0.Results:A total of 1054 refugee patients were examined for trachoma.179(16.98%) of them had clinical signs of trachoma.About 6(3.35%) patients had active trachoma with trachomatous trichiasis(TT),47(26.26%) patients had TT only and the rest 126(70.39%)patients had TT with trachomatous corneal opacity.All of the trachoma patients had blinding trachoma(TT with or without trachomatous corneal opacity),and about 60.89% of them had visual impairment.Blinding trachoma was significantly more common among females.patients in age group of 16-59 years,married patients,illiterates and Fugnido camp settlers(P<0.05).Conclusions:There is a very high burden of blinding trachoma among refugees.Urgent surgical intervention is needed to prevent blindness and low vision in the study subjects,and targeted regular outreach-based eye care service should be commenced.

  12. Psychomotor Development for the Deaf-Blind.

    Science.gov (United States)

    Sherrill, Claudine

    The stages of psychomotor development in deaf blind children and youth are reviewed, and educational principles to guide psychomotor development programs for the deaf blind are outlined. Etiological factors which contribute to the psychomotor development of deaf blind persons are discussed including nonambulation and sensory deprivation, heart…

  13. Comparative evaluation of calcium silicate-based dentin substitute (Biodentine®) and calcium hydroxide (pulpdent) in the formation of reactive dentin bridge in regenerative pulpotomy of vital primary teeth: Triple blind, randomized clinical trial

    Science.gov (United States)

    Grewal, Navneet; Salhan, Rubica; Kaur, Nirapjeet; Patel, Hemal Bipin

    2016-01-01

    Background: Considering the biological concerns of calcium hydroxide (CH) as a pulpotomy agent, an alternative silicate based dentin substitute i.e. Biodentine (Ca3SiO5) was evaluated clinically and radiographically. Aims: To evaluate the effectiveness of dentin substitute (Biodentine) in regenerative pulpotomy of vital primary teeth that would giv a biological base to its use in forming reactive dentin bridge and overcoming the drawbacks of calcium hydroxide. Material and Methods: Randomised clinical trial on 40 bilateral carious primary molars in 20 participant children (aged 5-10 years) was carried out by same operator using Ca3SiO5(group-1) and CH (group-2) as vital pulpotomy agents. Blinded clinical and radiographic outcomes were observed at 3, 6 and 12 months interval. Results: Clinical outcomes of both protocols were analysed using Pearson's chi-square test applied at P < 0.05. Descriptive statistics were expressed as mean increase in dentin bridge formation in mms from two reference points in standardized radiographs using paired ‘t’- test at baseline and 12 months and found to be statistically significant (P < 0.05) in group-1 when compared with group-2. Conclusion: Group-1 revealed statistically favourable regenerative potential along with clinical success compared to group 2 thereby sharing both indications and mode of action with CH, but without its drawbacks of physical and clinical properties. PMID:27994411

  14. A SDP-based method for blind equalization of SIMO channels%基于半正定规划的 SIMO 信道盲均衡方法

    Institute of Scientific and Technical Information of China (English)

    王大磊; 王秀秀; 韩啸

    2014-01-01

    针对数字通信单输入多输出(SIMO)系统中的信道盲均衡问题,使用优化理论中的半正定规划(SDP)方法,对采用随机梯度法求解的二阶统计量盲均衡算法(MSOSA)进行改进,给出了一种新的盲均衡求解算法SDP‐MSOSA 。相比采用随机梯度迭代法实现的MSOSA ,SDP‐MSOSA需要的数据样点更少,且收敛后的稳态误差更小,能够更加有效地消除码间干扰,仿真实验验证了算法SDP‐MSOSA的有效性。%Aiming at blind equalization in single‐input multiple‐output (SIMO) system in digital com‐munication ,an algorithm SDP‐MSOSA was proposed based on semi‐definite programming (SDP) to improve the modified second‐order statistics based algorithm (MSOSA) via stochastic gradient descent method .Compared to algorithm MSOSA realized by stochastic gradient descent method ,the algo‐rithm SDP‐MSOSA needs less samples ,and can achieve faster convergence speed and lower steady‐state error .Computer simulations demonstrate the validity of the algorithm SDP‐MSOSA .

  15. Comparative evaluation of calcium silicate-based dentin substitute (Biodentine® and calcium hydroxide (pulpdent in the formation of reactive dentin bridge in regenerative pulpotomy of vital primary teeth: Triple blind, randomized clinical trial

    Directory of Open Access Journals (Sweden)

    Navneet Grewal

    2016-01-01

    Full Text Available Background: Considering the biological concerns of calcium hydroxide (CH as a pulpotomy agent, an alternative silicate based dentin substitute i.e. Biodentine (Ca3SiO5 was evaluated clinically and radiographically. Aims: To evaluate the effectiveness of dentin substitute (Biodentine in regenerative pulpotomy of vital primary teeth that would giv a biological base to its use in forming reactive dentin bridge and overcoming the drawbacks of calcium hydroxide. Material and Methods: Randomised clinical trial on 40 bilateral carious primary molars in 20 participant children (aged 5-10 years was carried out by same operator using Ca3SiO5(group-1 and CH (group-2 as vital pulpotomy agents. Blinded clinical and radiographic outcomes were observed at 3, 6 and 12 months interval. Results: Clinical outcomes of both protocols were analysed using Pearson's chi-square test applied at P < 0.05. Descriptive statistics were expressed as mean increase in dentin bridge formation in mms from two reference points in standardized radiographs using paired 't'- test at baseline and 12 months and found to be statistically significant (P < 0.05 in group-1 when compared with group-2. Conclusion: Group-1 revealed statistically favourable regenerative potential along with clinical success compared to group 2 thereby sharing both indications and mode of action with CH, but without its drawbacks of physical and clinical properties.

  16. Efficacy and tolerability of a polysaccharide-resin-honey based cough syrup as compared to carbocysteine syrup for children with colds: a randomized, single-blinded, multicenter study

    National Research Council Canada - National Science Library

    Cohen, Herman Avner; Hoshen, Moshe; Gur, Shmuel; Bahir, Arie; Laks, Yoseph; Blau, Hannah

    2017-01-01

    .... The objective of this trial is to compare the effects of a polysaccharide-resin-honey based cough syrup, and carbocysteine syrups on nocturnal and daytime cough associated with childhood upper...

  17. Interference mitigation method based on subspace proj ection and blind adaptive beamforming%联合正交投影与盲波束形成的干扰抑制方法

    Institute of Scientific and Technical Information of China (English)

    刘海涛; 刘亚洲; 成玮; 张学军

    2015-01-01

    针对L频段数字航空通信系统1(L-band digital aeronautical communications system 1,L-DACS1)以内嵌方式部署在航空无线电导航频段而产生的高强度测距仪脉冲信号干扰正交频分复用(orthogonal frequency division multiplexing,OFDM)接收机的问题,提出联合正交投影与盲波束形成的干扰抑制方法。接收机首先通过将接收信号矢量投影到干扰信号正交补空间的方法消除高强度测距仪脉冲干扰,然后利用OFDM信号循环前缀的对称特性,基于期望信号与参考信号矢量内积度量最大化准则得到波束形成权值,并通过波束形成方法提取OFDM直射径信号。计算机仿真表明:论文提出方法可有效克服测距仪脉冲及 OFDM散射径信号的干扰,提高L频段数字航空通信系统1的链路传输的可靠性。%To mitigate the deleterious influence of distance measure equipment (DME)impulse interference on the orthogonal frequency division multiplexing (OFDM)receiver of L-band digital aeronautical communications system 1 (L-DACS1 )operating as an inlay system,a new interference suppression receiver for the L-DACS1 system is proposed based on jointing the subspace projection and the blind adaptive beam forming algorithm.Firstly,the subspace projec-tion algorithm is used to suppress the strong DME interference by proj ecting the array received signals on the orthogo-nal complement space of interferences.Then,the blind adaptive beam forming algorithm is proposed to extract the OFDM direct path signals based on inner product maximization criterion between the desired and reference signals. Computer simulation results show that the proposed OFDM receiver can effectively suppress the strong DME impulse interference and OFDM scattering signal and improve the reliability of the L-DACS1 system.

  18. Research on Materials of AlGaN Based p-i-n Solar-Blind Ultraviolet Detectors%AlGaN基p-i-n型日盲紫外探测器材料的研制

    Institute of Scientific and Technical Information of China (English)

    刘波; 袁凤坡; 尹甲运; 盛百城; 房玉龙; 冯志红

    2012-01-01

    AlN and high Al content AlGaN were grown on (0001) sapphire substrates by MOCVD. By optimizing the process parameters such as temperature, pressure, Ⅴ/Ⅲ ratio of AlN and AlGaN, the high quality A1N and AlGaN materials were obtained. X-ray ω (002) full width half maximum (FWHM) of AlN is 74 arcsec, the band edge of transmission spectrum is 205 nm and very sharp. X-ray ω (002) FWHM of Al0.45 GaN is 223 arcsec, the band edge of transmission spectrum is 272 nm and very sharp. The material for AlGaN based p-I-n solar-blind UV detector was grown by optimized processing, and the devices were fabricated. AlGaN based p-I-n solar-blind ultraviolet detectors were fabricated, the peak responsivity wavelength is 262 nm, and peak responsivity at zero bias voltage is 0. 117 A/W.%采用金属有机气相外延(MOCVD)方法在(0001)面蓝宝石衬底上生长了AlN和高铝组分AlGaN材料.通过优化AlN和AlGaN材料的生长温度、生长压力和Ⅴ族元素/Ⅲ族元素物质的量比(nⅤ/Ⅲ)等工艺条件,得到了高质量的AlN和高铝组分AlGaN材料.AlN材料X射线双晶衍射ε(002)半宽为74 arcsec,透射光谱测试带边峰位于205 nm,带边陡峭;Al组分为45%的AlGaN材料X射线双晶衍射ω(002)半宽为223 arcsec,透射光谱测试带边峰位于272 nm,带边陡峭.采用此外延工艺方法生长了AlGaN基p-i-n型日盲紫外探测器材料并进行了器件工艺流片,研制出AlGaN基p-i-n型日盲紫外探测器,响应峰值波长为262 nm,在零偏压下的峰值响应度达到0.117 A/W.

  19. 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.

  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 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

  1. Blind image quality assessment via deep learning.

    Science.gov (United States)

    Hou, Weilong; Gao, Xinbo; Tao, Dacheng; Li, Xuelong

    2015-06-01

    This paper investigates how to blindly evaluate the visual quality of an image by learning rules from linguistic descriptions. Extensive psychological evidence shows that humans prefer to conduct evaluations qualitatively rather than numerically. The qualitative evaluations are then converted into the numerical scores to fairly benchmark objective image quality assessment (IQA) metrics. Recently, lots of learning-based IQA models are proposed by analyzing the mapping from the images to numerical ratings. However, the learnt mapping can hardly be accurate enough because some information has been lost in such an irreversible conversion from the linguistic descriptions to numerical scores. In this paper, we propose a blind IQA model, which learns qualitative evaluations directly and outputs numerical scores for general utilization and fair comparison. Images are represented by natural scene statistics features. A discriminative deep model is trained to classify the features into five grades, corresponding to five explicit mental concepts, i.e., excellent, good, fair, poor, and bad. A newly designed quality pooling is then applied to convert the qualitative labels into scores. The classification framework is not only much more natural than the regression-based models, but also robust to the small sample size problem. Thorough experiments are conducted on popular databases to verify the model's effectiveness, efficiency, and robustness.

  2. Blind graph rewriting systems

    CERN Document Server

    Salikhmetov, Anton

    2012-01-01

    We consider a simple (probably, the simplest) structure for random access memory. This structure can be used to construct a universal system with nearly void processor, namely, we demonstrate that the processor of such a system may have empty instruction set, in a more strong manner than the existing ZISC (zero instruction set computer based on ideas for artificial neural networks) and NISC architecture (no instruction set computing). More precisely, the processor will be forbidden to analyze any information stored in the memory, the latter being the only state of such a machine. This particular paper is to cover an isolated aspect of the idea, specifically, to provide the logical operations embedded into a system without any built-in conditional statements.

  3. Blind compressive sensing dynamic MRI.

    Science.gov (United States)

    Lingala, Sajan Goud; Jacob, Mathews

    2013-06-01

    We propose a novel blind compressive sensing (BCS) frame work to recover dynamic magnetic resonance images from undersampled measurements. This scheme models the dynamic signal as a sparse linear combination of temporal basis functions, chosen from a large dictionary. In contrast to classical compressed sensing, the BCS scheme simultaneously estimates the dictionary and the sparse coefficients from the undersampled measurements. Apart from the sparsity of the coefficients, the key difference of the BCS scheme with current low rank methods is the nonorthogonal nature of the dictionary basis functions. Since the number of degrees-of-freedom of the BCS model is smaller than that of the low-rank methods, it provides improved reconstructions at high acceleration rates. We formulate the reconstruction as a constrained optimization problem; the objective function is the linear combination of a data consistency term and sparsity promoting l1 prior of the coefficients. The Frobenius norm dictionary constraint is used to avoid scale ambiguity. We introduce a simple and efficient majorize-minimize algorithm, which decouples the original criterion into three simpler subproblems. An alternating minimization strategy is used, where we cycle through the minimization of three simpler problems. This algorithm is seen to be considerably faster than approaches that alternates between sparse coding and dictionary estimation, as well as the extension of K-SVD dictionary learning scheme. The use of the l1 penalty and Frobenius norm dictionary constraint enables the attenuation of insignificant basis functions compared to the l0 norm and column norm constraint assumed in most dictionary learning algorithms; this is especially important since the number of basis functions that can be reliably estimated is restricted by the available measurements. We also observe that the proposed scheme is more robust to local minima compared to K-SVD method, which relies on greedy sparse coding. Our

  4. Color blindness and Rorschach color responsivity.

    Science.gov (United States)

    Corsino, B V

    1985-10-01

    Color vision deficits occur in 10% of the American white male population. Thus, color blindness may invalidate diagnostic hypotheses generated from Rorschach data. The Rorschach protocols of 43 white, college male color-blind subjects were compared to the protocols of normally sighted controls. The color-blind group manifested fewer pure "C" responses. No significant between group differences emerged for any of the other primary Rorschach color variables. Pure "C" responses rarely figure prominently in Rorschach evaluations, and the apparent lowered frequency of these responses by the color-blind is insufficient to warrant modification of current Rorschach practice. The data suggest that color blindness is unlikely to confound Rorschach assessment.

  5. BLIND SERBIAN RULERS AND FAMOUS PERSONS

    Directory of Open Access Journals (Sweden)

    Janicijevic Katarina

    2016-12-01

    Full Text Available History and medicine were an integral part of life-being of blind serbian acters. One of the main actors was half-blind serbian ruler, Stefan of Decani and whose name was associated with first ophthalmologic hospital and precursor of the eye`s injuries care. After, national reputation as Stefan Blind Righteous, ruler of the Serbian despot between 1458. and 1459. (member of Brankovic`s dinasty, and he was blinded by eye injuries burns. The famous national was also Filip Visnjic, as blind minstrel and authentic creator of serbian folk traditions, with sequels as a child, by bilateral infective panuveitis.

  6. Fighting crime by fighting misconceptions and blind spots in policy theories: an evidence-based evaluation of interventions and assumed causal mechanisms

    NARCIS (Netherlands)

    van Noije, L.; Wittebrood, K.

    2010-01-01

    How effective are policy interventions to fight crime and how valid is the policy theory that underlies them? This is the twofold research question addressed in this article, which presents an evidence-based evaluation of Dutch social safety policy. By bridging the gap between actual effects and

  7. Effect of workplace- versus home-based physical exercise on pain in healthcare workers: study protocol for a single blinded cluster randomized controlled trial.

    Science.gov (United States)

    Jakobsen, Markus D; Sundstrup, Emil; Brandt, Mikkel; Kristensen, Anne Zoëga; Jay, Kenneth; Stelter, Reinhard; Lavendt, Ebbe; Aagaard, Per; Andersen, Lars L

    2014-04-07

    The prevalence and consequences of musculoskeletal pain is considerable among healthcare workers, allegedly due to high physical work demands of healthcare work. Previous investigations have shown promising results of physical exercise for relieving pain among different occupational groups, but the question remains whether such physical exercise should be performed at the workplace or conducted as home-based exercise. Performing physical exercise at the workplace together with colleagues may be more motivating for some employees and thus increase adherence. On the other hand, physical exercise performed during working hours at the workplace may be costly for the employers in terms of time spend. Thus, it seems relevant to compare the efficacy of workplace- versus home-based training on musculoskeletal pain. This study is intended to investigate the effect of workplace-based versus home-based physical exercise on musculoskeletal pain among healthcare workers. This study was designed as a cluster randomized controlled trial performed at 3 hospitals in Copenhagen, Denmark. Clusters are hospital departments and hospital units. Cluster randomization was chosen to increase adherence and avoid contamination between interventions. Two hundred healthcare workers from 18 departments located at three different hospitals is allocated to 10 weeks of 1) workplace based physical exercise performed during working hours (using kettlebells, elastic bands and exercise balls) for 5 × 10 minutes per week and up to 5 group-based coaching sessions, or 2) home based physical exercise performed during leisure time (using elastic bands and body weight exercises) for 5 × 10 minutes per week. Both intervention groups will also receive ergonomic instructions on patient handling and use of lifting aides etc. Inclusion criteria are female healthcare workers working at a hospital. Average pain intensity (VAS scale 0-10) of the back, neck and shoulder (primary outcome) and physical

  8. 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.

  9. Rationale and methods of the iFightDepression study: A double-blind, randomized controlled trial evaluating the efficacy of an internet-based self-management tool for moderate to mild depression.

    Science.gov (United States)

    Justicia, Azucena; Elices, Matilde; Cebria, Ana Isabel; Palao, Diego J; Gorosabel, Jesús; Puigdemont, Dolors; de Diego-Adeliño, Javier; Gabilondo, Andrea; Iruin, Alvaro; Hegerl, Ulrich; Pérez, Víctor

    2017-04-19

    During the last decade online interventions have emerged as a promising approach for patients with mild/moderate depressive symptoms, reaching at large populations and representing cost-effective alternatives. The main objective of this double-blind, randomized controlled trial is to examine the efficacy of an internet-based self-management tool (iFightDepression) for mild to moderate depression as an add-on to treatment as usual (TAU) versus internet-based psychoeducation plus TAU. A total of 310 participants with major depression disorder (MDD) will be recruited at four different mental-health facilities in Spain. Participants will be randomly allocated to one of two study arms: iFightDepression (iFD) tool + TAU vs. internet-based psychoeducation + TAU. Both interventions last for 8 weeks and there is a 12 weeks follow up. The primary outcome measure is changes in depressive symptoms assessed with the Hamilton Depression Rating Scale. Additionally, pre-post interventions assessments will include socio-demographic data, a brief medical and clinical history and self-reported measures of depressive symptoms, quality of life, functional impairments and satisfaction with the iFD tool. iFightDepression is an easy-prescribed tool that could increase the efficacy of conventional treatment and potentially reach untreated patients, shortening waiting lists to receive psychological treatment. Confirming the efficacy of the iFD internet-based self-management tool as an add-on treatment for individuals with mild to moderate depression will be clinically-relevant. Registration number NCT02312583 . Clinicaltrials.gov . December 4, 2014.

  10. Jogging Program for Deaf-Blind Students Improves Condition and Reduces Self-Stimulation.

    Science.gov (United States)

    Alajajian, Lisa D.

    Four deaf-blind students at the Massachusetts Association for the Blind were involved in a pilot aerobic program consisting of jogging for 15-20 minutes three times a week. Students were chosen based on their enjoyment of this fast movement and they were given clearance for this activity by both a doctor and a physical therapist. The students'…

  11. Blind equalization of underwater acoustic channels using implicit higher-order statistics

    NARCIS (Netherlands)

    Blom, Koen C.H.; Dol, Henry S.; Kokkeler, André B.J.; Smit, Gerard J.M.

    2016-01-01

    In order to reduce the length of transmission time slots and energy consumption of underwater modems, this work focuses on equalization without the need for training sequences. This type of equalization is known as blind equalization. A blind equalizer cascade based on higher-order statistics is pre

  12. The 2013 National Child Count of Children and Youth Who Are Deaf-Blind

    Science.gov (United States)

    National Center on Deaf-Blindness, 2014

    2014-01-01

    The National Child Count of Children and Youth who are Deaf-Blind is the first and longest running registry and knowledge base of children who are deaf-blind in the world. It has been collaboratively designed, implemented and revised to serve as the common vehicle to meet federal grant requirements for both the State/Multi-State and National…

  13. [Cortical plasticity in blind individual].

    Science.gov (United States)

    Wang, Shu-zhen; Zhu, Si-quan

    2008-10-01

    The cognitive mechanisms and functional brain imaging research on blind individuals provide special information for exploring the plasticity of the developing human brain. This paper focuses on five aspects of recent progress in this field: (1) the behavior compensation of the blind; (2) the influence of early visual deprivation and later visual deprivation on cross-modal reorganization; (3) the relationship between the complexity of task requirement and cross-modal reorganization; (4) the relationship between the sensitive periods of the visual system and the time course of cross-modal reorganization; (5) the neural mechanisms of cross-modal reorganization. These findings contribute greatly to the theoretical basis of the rehabilitation of individuals with perceptual deficits.

  14. An Orthogonal Wavelet Transform Weighted Multi-Modulus Blind Equalization Algorithm Based on SA-GSO%基于SA-GSO的小波加权多模盲均衡算法

    Institute of Scientific and Technical Information of China (English)

    高敏; 郭业才

    2012-01-01

    When MMA(Multi -modulus Algorithm) is used to equalize high -order QAM, it has many disadvantages, such as slow convergence rate, large mean square error, and so on. In order to overcome the problems, an orthogonal wavelet transform weighted multi - modulus blind equalization algorithm based on simulated annealing optimization glowworm swarm algorithm ( SA - GSO - WT - MMA) was proposed. In the proposed algorithm , the weighted item was increased to the traditional multi - modulus blind equalization algorithm (MMA) , and the simulated annealing glowworm swarm optimization algorithm and the wavelet transform were also introduced in. The proposed algorithm can adjust the modulus value of the cost function value by using the weighted item, it can optimize the initial weight vector of the equalizer by using the strong global optimization ability of SA - GSO , and reduce the signal autocorrelation by using the de - correlation ability of WT. The results from computer simulation show that the proposed algorithm was excellence in improving the convergence rate and reducing the steady - state error.%为解决传统多模盲均衡算法(MMA)在均衡高阶QAM信号时存在的收敛速度慢、稳态误差大等问题,提出了一种基于模拟退火萤火虫优化的小波加权多模盲均衡算法(SA-GSO-WT-WMMA).该算法在MMA的基础上增加了加权项,并引入了模拟退火萤火虫优化(SA-GSO)算法和正交小波变换(Wr),利用加权项自适应地调整算法中代价函数的模值,利用SA-GSO算法极强的全局寻优能力来优化均衡器的初始权向量,利用正交小波变换降低信号的自相关性,有效提高了均衡效果.水声信道仿真实验表明,该算法在降低稳态均方误差和加速收敛速度两方面表现卓越.

  15. 基于子空间盲多用户检测算法的设计和仿真%Design and simulation of blind multiuser detection based on subspace

    Institute of Scientific and Technical Information of China (English)

    王钧

    2012-01-01

    With the rapid development of mobile communication techonology, CDMA (Code Division Multiple Access) as core techonology of the third generation of mobile communication becomes entering into peoples common life. CDMA has the advantage of large capacity, soft capacity and anti-multipath fading, but the existence of MAI ( Multiple Access Interference ) has serious impact on system performance and capacity. So how to eliminate and control this kind of interference becomes one hot topic of CDMA research. Third-generation mobile communication system has multi-user detection (MUD) to overcome the multiple access interference as one of the effective ways. This paper mainly researches on the direct sequence and spread spectrum code division multiple access ( DS-CDMA) system in the blind multiuser detection algorithm, deeply researches on the multi-user detection based on the constant modulus blind adaptive Kalman filtering algorithm. The method that Kalman filter algorithm introduced subspace improved Kalman filtering algorithm efficiency.%随着数字移动通信技术的飞速发展,以码分多址(CDMA)为核心的第三代移动通信(3G)技术已经走入人们的日常生活.CDMA系统具有容量大、软容量、抗多径衰落强等优点,但多址干扰(MAI)的存在却严重的影响了系统的性能和容量,因此如何消除和抑制这种干扰就成了CDMA技术研究的热门话题之一,第三代移动通信系统已经将多用户检测技术(MUD)作为克服多址干扰的有效方法之一.文中主要研究了直接序列扩频码分多址( DS - CDMA)系统中的盲多用户检测算法,深入的研究了基于卡尔曼滤波的盲多用户检测算法,通过在卡尔曼滤波算法上引入子空间提高了原有卡尔曼滤波算法的效率.

  16. Blind Watermarking Algorithm for Color Images in Wavelet Domain based on Differential Evolution%基于差分进化的小波域彩色图像盲水印算法

    Institute of Scientific and Technical Information of China (English)

    吴万旭; 牛钰莹; 刘甜甜; 赵全超

    2016-01-01

    针对因嵌入水印而造成图像视觉损失的问题,提出了一种基于差分进化的DWT-SVD数字水印盲检测算法。首先对水印图像进行置乱加密处理,其次对需要嵌入水印的图像进行离散小波变换,得到其低频、中频、次高频、高频四个子代,再次将置乱后的水印按照一定的方法嵌入到载体图像对应的奇异值矩阵S中,完成水印嵌入。最后,利用差分进化算法修改奇异值分解中的酉阵U和V,以弥补因添加水印造成的视觉损失。实验结果表明,该算法在保证水印鲁棒性情况下,使嵌入水印后的图像质量得到了有效提高。此外该算法在水印提取阶段不需要载体图像的参与,实现了水印的盲检测。%Aiming at the problem of visual loss caused by watermark embedding, a DWT-SVD digital wa-termarking blind detection algorithm based on differential evolution is proposed. Firstly, Arnold scrambling pretreatment is done on watermark image, and the host image decomposed by DWT,thus generating+ four different bands sub-maps, including the low frequency, intermediate frequency, sub-high frequency and high frequency. Then, the watermark image is embedded in S matrix after decomposition by singular value in the watermark of each block. Finally, a differential evolution algorithm is applied to modifying the U and V matrix, thus to remedy the visual loss caused by embedding in S matrix. Experimental results show that this algorithm could effectively improve image quality after watermarking being embadded while main-taining the robustness. In addition,no carrier image is needed in watermarking extraction stage, this indi-cates that the proposed algorithm could achieve blind detection of watermarking.

  17. A method of detecting re-sampling based on expectation maximization applied in audio blind forensics%音频盲取证中一种基于EM的重采样检测方法

    Institute of Scientific and Technical Information of China (English)

    陈雁翔; 吴玺

    2012-01-01

    盲取证指针对篡改信号无需添加任何附加信息就可鉴别出信号的真伪,而音频篡改中篡改者经常利用重采样以达到更好的篡改效果,因此重采样检测作为音频盲取证的重要组成部分得到了高度的重视.对信号的重采样会引入相关性,这种相关性是周期出现的,本文通过基于期望最大化的检测方法揭示这种相关性,并通过判断这种相关性是否呈现周期性达到检测目的.在检测流程中采取了奇异防止、低频段去除、归一化三阶原点矩等措施,达到了更好的检测效果.实验验证了该方法对于各种插值函数的鲁棒性,以及不同重采样率下和音频拼接篡改时检测的有效性.%Blind forensics can discriminate such tampered signal without any additional information. During the audio tampering tampers often use re-sampling to achieve better results, thus re-sampling detection obtained the high value as an important aspect of blind forensics. Re-sampling will introduce correlation and this relationship is often periodic. We use method based on Expectation Maximization to reveal the correlation and reach the purpose of detection by checking whether the correlation is periodic. To achieve better effect, we also take the steps of singularity prevention, low-band elimination and normalized 3-order origin moment. The experiment results show the robustness of interpolating functions, and the validity of detection under different re-sampling rates as well as during splice tampering.

  18. Effect of the Medicinal Agaricus blazei Murill-Based Mushroom Extract, AndoSanTM, on Symptoms, Fatigue and Quality of Life in Patients with Crohn's Disease in a Randomized Single-Blinded Placebo Controlled Study.

    Directory of Open Access Journals (Sweden)

    Stig Palm Therkelsen

    Full Text Available Ingestion of AndoSanTM, based on the mushroom Agaricus blazei Murill, has previously shown an anti-inflammatory effect through reduction of pro-inflammatory cytokines in healthy individuals and patients with Crohn's disease (CD. In this randomized single-blinded placebo-controlled study we examined whether intake of AndoSanTM also resulted in clinical effects.50 patients with symptomatic CD were randomized for oral daily consumption of AndoSanTM or placebo for a 21-day experimental period, in this per-protocol study. Patients reported validated scores for symptoms, fatigue and health related quality of life (HRQoL at days 0, 14 and 21. Fecal calprotectin and general blood parameters were also analyzed. In the AndoSanTM group (n = 25 symptoms improved from baseline (day 0 to days 14 and 21, with respective mean scores (95% CI of 5.52 (4.64-6.40, 4.48 (3.69-5.27 and 4.08 (3.22-4.94 (p<0,001. We found significant improvements in symptom score for both genders in the AndoSanTM group, and no significant changes in the placebo (n = 25 group. There were however no significant differences between the groups (p = 0.106, although a marginal effect in symptom score for men (p = 0.054. There were comparable improvements in physical, mental and total fatigue for both groups. HRQoL versus baseline were at day 21 improved for bodily pain and vitality in the AndoSanTM group and for vitality and social functioning in the placebo group. No crucial changes in general blood samples and fecal calprotectin were detected.The results from this single-blinded randomized clinical trial shows significant improvement on symptoms, for both genders, in the AndoSanTM group, but no significant differences between the study groups. The results on fatigue, HRQoL, fecal calprotectin and blood samples were quite similar compared with placebo. The patients did not report any harms or unintended effects of AndoSanTM. CD patients with mild to moderate symptoms may have beneficiary

  19. Effect of a Medicinal Agaricus blazei Murill-Based Mushroom Extract, AndoSan™, on Symptoms, Fatigue and Quality of Life in Patients with Ulcerative Colitis in a Randomized Single-Blinded Placebo Controlled Study.

    Directory of Open Access Journals (Sweden)

    Stig Palm Therkelsen

    Full Text Available Ingestion of AndoSan™, based on the mushroom Agaricus blazei Murill, has previously been shown to exhibit anti-inflammatory effects because of reduction of pro-inflammatory cytokines in healthy individuals and patients with ulcerative colitis. In this randomized single-blinded placebo controlled study we examined whether intake of AndoSan™ also resulted in clinical effects.50 patients with symptomatic ulcerative colitis were block-randomized and blinded for oral daily intake of AndoSan™ or placebo for the 21 days' experimental period. The patients reported scores for symptoms, fatigue and health related quality of life (HRQoL at days 0, 14 and 21. Fecal calprotectin and general blood parameters were also analyzed. In the AndoSan™ group (n = 24 symptoms improved from baseline (day 0 to days 14 and 21, with respective mean scores (95% CI of 5.88 (4.92-6.83, 4.71 (3.90-5.52 (p = 0.002 and 4.50 (3.70-5.30 (p = 0.001. Corresponding improved mean scores (±SD for total fatigue were 16.6 (5.59, 14.1 (4.50 (p = 0.001 and 15.1 (4.09 (p = 0.023. These scores in the placebo group (n = 26 were not improved. When comparing the two study groups using mixed model statistics, we found significant better scores for the AndoSan™-patients. HRQoL for dimensions bodily pain, vitality, social functioning and mental health improved in the AndoSan™ group. There were no alterations in general blood samples and fecal calprotectin.Beneficiary effects on symptoms, fatigue and HRQoL from AndoSan™ consumption were demonstrated in this per-protocol study, supporting its use as a supplement to conventional medication for patients with mild to moderate symptoms from ulcerative colitis. The patients did not report any harms or unintended effects of AndoSan™ in this study.ClinicalTrials.gov NCT01496053.

  20. TOOLS TO INCLUDE BLIND STUDENTS IN SCHOOL BUILDING PERFORMANCE ASSESSMENTS

    Directory of Open Access Journals (Sweden)

    Tania Pietzschke Abate

    2016-05-01

    Full Text Available This article discusses the design of data collection instruments that include the opinions of blind students, in accordance with the principles of Universal Design (UD. The aim of this study is to understand the importance of adapting data collection instruments for the inclusion of disabled persons in field research in Architecture and Design, among other fields. The data collection instruments developed were a play interview with a tactile map and a 3D survey with the use of tactile models. These instruments sought to assess the school environment experienced by blind students. The study involved students from the early years of a school for the blind who had not yet mastered the Braille system. The participation of these students was evaluated. A multidisciplinary team consisting of architects, designers, educators, and psychologists lent support to the study. The results showed that the data collection instruments adapted to blind students were successful in making the group of authors examine questions regarding UD. An analysis of the participatory phase showed that the limitations resulting from blindness determine the specificities in the adaptation and implementation process of the instruments in schools. Practical recommendations for future studies related to instruments in the UD thematic are presented. This approach is in line with the global trend of including disabled persons in society based on these users’ opinions concerning what was designed by architects and designers.

  1. PA01.17. A clinical study to evaluate the effect of extract based herbal formulation on hypertension- a single blinded standard controlled randomized study

    OpenAIRE

    Agrawal, Satish; Pol, Hemant; ,

    2012-01-01

    Purpose: In Ayurveda although there is no such terminology like hypertension but still this work is an approach to establish relationship between Hypertension & vitiated functioning of three governing forces of our body i.e. Tridosha and to treat Hypertension on Ayurvedic principles. The logic behind such correlation is based on the fact that, like other physiological processes, B.P. too is normal phenomenon of our body which is governed by Tridosha. After going through modern pathogenesis of...

  2. A Blind Equalization Algorithm Based on Fractionally Spaced Sampling for PCM-FM%一种适用于 PCM-FM 信号的分数间隔盲均衡算法

    Institute of Scientific and Technical Information of China (English)

    陈静; 曾海彬; 徐秀成; 孟玮

    2016-01-01

    针对遥测系统中频率选择性衰落造成的严重码间干扰问题,提出了一种适用于 PCM-FM 信号的分数间隔盲均衡算法。该算法利用 PCM-FM 信号的恒模特性,采用过采样技术提高了收敛速度,并对宽带遥测两径信道模型进行了均衡仿真。仿真结果表明,该方法能够较好地对抗频率选择性多径衰落,消除码间干扰。%To overcome the inter-symbol interference caused by the frequency-selective fading in the telemetry system,a blind equalization algorithm based on fractionally spaced sampling for PCM-FM is proposed in this paper.According to the constant modulus of PCM-FM,the proposed algorithm uses the over-sampling technology to increase the convergence rate.The algorithm is simulated on the wideband channel model for aeronautical telemetry.Simulation results show that the proposed algorithm can effectively equalize the ISI caused by the frequency-selective fading.

  3. Clinical efficacy of new aloe vera- and myrrh-based oral mucoadhesive gels in the management of minor recurrent aphthous stomatitis: a randomized, double-blind, vehicle-controlled study.

    Science.gov (United States)

    Mansour, Ghada; Ouda, Soliman; Shaker, Ahmed; Abdallah, Hossam M

    2014-07-01

    To evaluate the clinical efficacy, and safety of newly customized natural oral mucoadhesive gels, containing either aloe vera or myrrh as active ingredients, in the management of minor recurrent aphthous stomatitis (MiRAS). Ninety subjects with MiRAS were recruited from Oral Medicine Clinic, at Faculty of Dentistry, King Abdulaziz University, Saudi Arabia, for this randomized, double-blind, placebo-controlled study. Two new natural gels, containing aloe vera and myrrh, were prepared in a concentration of (0.5% w/w), in addition to a plain mucoadhesive gel used as a placebo. Patients with fresh ulcers (aloe gel showed complete ulcer healing, 86.7%, and 80% of them revealed subsidence of erythema and exudation, respectively, especially at day 6 visit, whereas 76.7% of myrrh-treated patients revealed almost absence of pain at day 6. No side effects were encountered with the use of any of the three gels. The new formulated aloe- and myrrh-based gels proved to be effective in topical management of MiRAS. Aloe was superior in decreasing ulcer size, erythema, and exudation; whereas myrrh resulted in more pain reduction. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  4. 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.

  5. Comparing Whole Building Energy Implications of Sidelighting Systems with Alternate Manual Blind Control Algorithms

    Directory of Open Access Journals (Sweden)

    Christopher Dyke

    2015-05-01

    Full Text Available Currently, there is no manual blind control guideline used consistently throughout the energy modeling community. This paper identifies and compares five manual blind control algorithms with unique control patterns and reports blind occlusion, rate of change data, and annual building energy consumption. The blind control schemes detailed here represent five reasonable candidates for use in lighting and energy simulation based on difference driving factors. This study was performed on a medium-sized office building using EnergyPlus with the internal daylight harvesting engine. Results show that applying manual blind control algorithms affects the total annual consumption of the building by as much as 12.5% and 11.5% for interior and exterior blinds respectively, compared to the Always Retracted blinds algorithm. Peak demand was also compared showing blind algorithms affected zone load sizing by as much as 9.8%. The alternate algorithms were tested for their impact on American Society of Heating, Refrigeration and Air-Conditioning Engineers (ASHRAE Guideline 14 calibration metrics and all models were found to differ from the original calibrated baseline by more than the recommended ±15% for coefficient of variance of the mean square error (CVRMSE and ±5% for normalized mean bias error (NMBE. The paper recommends that energy modelers use one or more manual blind control algorithms during design stages when making decisions about energy efficiency and other design alternatives.

  6. Blind channel estimation for redundant precoded OFDM systems

    Institute of Scientific and Technical Information of China (English)

    Liang Yongming; Luo Hanwen; Wu Yadong; Huang Jianguo

    2007-01-01

    Considering that channel estimation can play a crucial role in coherent detection of the information symbols in each data block, a blind channel estimation approach is proposed for redundant precoded orthogonal frequency-division multiplexing (OFDM) systems. A redundant linear frequency-domain precoder is applied to each pair of blocks before they enter the OFDM system. Because of the introduced structure, the frequency-selective channel can be identified at the receiver based on autocorrelation operations, singular value decomposition (SVD),and by resolving the scalar ambiguity. The proposed channel estimation method has low computational complexity and requires no prior statistical information on channel or noise. And the proposed blind method has high spectral efficiency owing to exploiting no training sequence. Computer simulations confirm that this proposed blind channel estimation method can identify the frequency-selective channels perfectly and obtain a good performance.

  7. Clinical efficacy of formula-based bifrontal versus right unilateral electroconvulsive therapy (ECT) in the treatment of major depression among elderly patients: a pragmatic, randomized, assessor-blinded, controlled trial.

    Science.gov (United States)

    Bjølseth, Tor Magne; Engedal, Knut; Benth, Jūratė Šaltytė; Dybedal, Gro Strømnes; Gaarden, Torfinn Lødøen; Tanum, Lars

    2015-04-01

    No prior study has compared the efficacy of bifrontal (BF) vs right unilateral (RUL) electroconvulsive therapy (ECT) by including the subgroup that is most likely to receive it: only elderly patients with major depression (MD). This single-site, randomized, assessor-blinded, controlled trial was conducted from 2009 to 2013. Seventy-three elderly patients with MD, unipolar and bipolar, were treated with a course of formula-based BF ECT or RUL ECT. The 17-item Hamilton Rating Scale for Depression (HRSD17) was used to measure efficacy. Safety was assessed with the Mini Mental State Examination (MMSE). Both electrode placements resulted in highly significant downward trends in symptom severity (all p<0.001), with a non-significant difference between methods (p=0.703). At the end of the ECT course, response rates for the BF and RUL group were 63.9% and 67.6%, respectively. Short-term remission, defined as an HRSD17 score≤7, was achieved in 14 (38.9%) patients in the BF group and 19 (51.4%) patients in the RUL group. Global cognitive function, as measured by the MMSE, did not deteriorate in the two treatment groups. The small number of subjects may have led to reduced power to detect real differences. The MMSE is not sufficient to ascertain the negative effect of ECT on cognition. This study indicates that formula-based BF and RUL ECT are equally efficacious, and that remission rates of formula-based dosing are lower than those previously reported for titrated dosing, in a clinical sample of elderly patients with MD. ClinicalTrials.gov NCT01559324. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  8. Photodynamic therapy of actinic keratoses with 8% and 16% methyl aminolaevulinate and home-based daylight exposure: a double-blinded randomized clinical trial

    DEFF Research Database (Denmark)

    Wiegell, S.R.; Haedersdal, M.; Eriksen, P.;

    2009-01-01

    . Methods Thirty patients with mostly thin-grade AK of the face or scalp were treated with 16% and 8% MAL-PDT in two symmetrical areas after application of sunscreen. Immediately after, patients left the hospital with instructions to spend the remaining day outside at home in daylight. Patients scored pain......-based daylight-mediated MAL-PDT was an effective and well-tolerated treatment for AK. No differences in response rates or adverse events were found between the areas treated with 16% MAL and with 8% MAL Udgivelsesdato: 2009/6...

  9. Development and Blind Clinical Validation of a MicroRNA Based Predictor of Response to Treatment with R-CHO(E)P in DLBCL

    DEFF Research Database (Denmark)

    Knudsen, S.; Hother, C.; Gronbaek, K.;

    2015-01-01

    on the measured growth inhibition of 60 human cancer cell lines (NCI60) in the presence of doxorubicine, cyclophosphamide, vincristine and etoposide as well as the baseline microRNA expression of the 60 cell lines, a microRNA based response predictor to CHOP was developed. The response predictor consisting of 20...... Prognostic Index (IPI) was included in the prediction analysis, the separation between responders and non-responders improved (P = 0.001). Thirteen patients developed relapse, and five patients predicted sensitive to their second and third line treatment survived a median 1194 days, while eight patients...

  10. Alabama School for the Blind Fitness and Nutrition Project.

    Science.gov (United States)

    Patterson, Douglas

    This project compared the relative physical fitness levels of 30 visually handicapped/blind students (aged 7-18) at a residential school with that of non-handicapped peers, to develop a school-based fitness and nutrition intervention program and determine impact of the intervention. The compounding handicapping nature of fitness deficits and…

  11. 'Blind' transfusion of blood products in exsanguinating trauma patients.

    NARCIS (Netherlands)

    Geeraedts, L.M.G.; Demiral, H.; Schaap, N.P.M.; Kamphuisen, P.W.; Pompe, J.C.; Frolke, J.P.M.

    2007-01-01

    BACKGROUND: In trauma, as interventions are carried out to stop bleeding, ongoing resuscitation with blood products is of vital importance. As transfusion policy in exsanguinating patients cannot be based on laboratory tests, transfusion of blood products is performed empirically or 'blindly'. The a

  12. The Effect of Sufentanil Administration on Remifentanil-Based Anaesthesia during Laparoscopic Gynaecological Surgery: A Double-Blind Randomized Controlled Trial

    Directory of Open Access Journals (Sweden)

    Ilsoon Son

    2014-01-01

    Full Text Available This study assessed the effect of sufentanil administered before conclusion of remifentanil-based anaesthesia on postoperative hyperalgesia and haemodynamic stability in patients undergoing laparoscopic gynaecological surgery. The patients were randomly allocated to a sufentanil administration group (S group or a normal saline administration group (C group. Anaesthesia was induced and maintained with controlled administration of remifentanil at 10 ng·mL−1 and propofol under bispectral index guidance. Once the surgical specimen was procured, sufentanil or normal saline was administered at 0.15 ng·mL−1 and maintained until extubation. The haemodynamic status during anaesthetic emergence was evaluated. The pain and postoperative nausea and vomiting (PONV were assessed for 72 h following postanaesthetic care unit (PACU discharge. The S group had significantly lower mean systemic arterial blood pressure and heart rate changes between the start of drug administration and extubation. Postoperative pain was significantly lower in the S group until 24 h following PACU discharge. There were no significant differences in PONV incidence and severity 72 h after PACU discharge between the two groups. Sufentanil administration before concluding remifentanil-based anaesthesia improved postoperative hyperalgesia and achieved haemodynamic stability at extubation without delaying recovery or increasing PONV during laparoscopic gynaecological surgery. Clinical trial registration is found at KCT0000785.

  13. Home-based hand rehabilitation after chronic stroke: Randomized, controlled single-blind trial comparing the MusicGlove with a conventional exercise program

    Directory of Open Access Journals (Sweden)

    Daniel K. Zondervan, PhD

    2016-07-01

    Full Text Available Individuals with chronic stroke have limited options for hand rehabilitation at home. Here, we sought to determine the feasibility and efficacy of home-based MusicGlove therapy. Seventeen participants with moderate hand impairment in the chronic phase of stroke were randomized to 3 wk of home-based exercise with either the MusicGlove or conventional tabletop exercises. The primary outcome measure was the change in the Box and Blocks test score from baseline to 1 mo posttreatment. Both groups significantly improved their Box and Blocks test score, but no significant difference was found between groups. The MusicGlove group did exhibit significantly greater improvements than the conventional exercise group in Motor Activity Log Quality of Movement and Amount of Use scores 1 mo posttherapy (p = 0.007 and p = 0.04, respectively. Participants significantly increased their use of MusicGlove over time, completing 466 gripping movements per day on average at study end. MusicGlove therapy was not superior to conventional tabletop exercises for the primary end point but was nevertheless feasible and led to a significantly greater increase in self-reported functional use and quality of movement of the impaired hand than conventional home exercises.

  14. 一种基于输出过采样的IIR盲均衡算法%A Blind Equalization Algorithm for IIR Channel Based on Oversampling

    Institute of Scientific and Technical Information of China (English)

    杨鑫伟; 赵乐军

    2012-01-01

    基于对IIR信道输出过采样,构造了一种单输入多输出(SIMO)信道模型。在该模型中,由于在AR子信道采用RLS迭代算法和在MA子信道采用了一种改进的CMA算法,从而使得该算法比传统算法更简化,收敛速度得到提高。仿真实验结果验证了该算法的有效性。%Based on the oversampling to the output of the IIR channel, this paper constructs a SIMO (single input multiple output) channel model. In this model, RLS algorithm and the improved CMA algorithm are adopted, respectively, in AR sub-channel and MA sub-channel such that this algorithm is much simpler than the traditional algorithm, and can attain faster convergence. Simulation results verify the effectiveness of the proposed algorithm.

  15. Investigation of ternary and quaternary high-temperature fixed-point cells, based on platinum-carbon-X, as blind comparison artefacts

    Science.gov (United States)

    Dong, W.; Machin, G.; Bloembergen, P.; Lowe, D.; Wang, T.

    2016-11-01

    Extensive studies of platinum-carbon eutectic alloy based high temperature fixed point cells have shown that this alloy has extremely good metrological potential as a temperature reference. However, it’s possible adoption as an accepted reference standard means that its eutectic temperature value will soon be agreed with an uncertainty less than most radiation thermometry scales at that temperature. Thus it will lack credibility if used as a future scale comparison artefact. To avoid this, the fixed-point cell can be deliberately doped with an impurity to change its transition temperature by an amount sufficient to test the accuracy of the scales of the institutes, involved in the comparison. In this study dopants of palladium and iridium were added to platinum-carbon to produce ternary alloy and quaternary alloy fixed-point cells. The stability of these artefacts was demonstrated and the fixed-point cells were used to compare the ITS-90 scales of NIM and NPL. It was found that the fixed point temperatures could be changed by an appreciable amount while retaining the stability and repeatability required for comparison artefacts.

  16. A NOVEL CHANNEL BLIND IDENTIFICATION ALGORITHM BASED ON DISTRIBUTION OF CHANNEL NEAR-COMMON ZEROS%一种新颖的基于信道近零点分布的盲辨识算法

    Institute of Scientific and Technical Information of China (English)

    白曜铭; 蒋建中; 孙有铭

    2013-01-01

    By studying the distribution of channel zeros produced by sub-space algorithm in the circumstance of over estimating the channel order, it is found that the additionally introduced common zeros in noisy environment are gathered around the unit circle in clusters , and the correlated theoretical analysis is presented in the paper as well .On this basis , a simple and novel algorithm of blind identification based on the distribution of the channel near-common zeros is proposed .Combined with the over estimation information obtained from a modified NECOE algorithm also based on sub-space, the correct channel estimation can be achieved by removing the common zeros from the estimated channel zeros.Simulation verifies that this algorithm has good performance with a low complexity under the condition of lower SNR .%研究子空间算法在阶数过估计时的信道零点分布,发现在有噪情况下额外引入的“公共零点”呈单位圆聚集性,并给出相关的理论分析。基于此,提出一种简单新颖的基于信道近零点分布的盲辨识算法。结合同样基于子空间的NECOE改进算法所得到的过估计信息,从估计的信道零点中移除“公共零点”,从而实现正确的信道估计。仿真验证了该算法在较低信噪比情况下性能良好,复杂度低。

  17. The Effect of Home based Exercise on Treatment of Women with Poly Cystic Ovary Syndrome; a single-Blind Randomized Controlled Trial

    Directory of Open Access Journals (Sweden)

    Farzaneh Vasheghani-Farahani

    2017-01-01

    Full Text Available Background: The most common reproductive endocrine disorder of reproductive age women is a Poly cystic ovary syndrome (PCOS Metabolic syndrome has been more reported in patients with PCOS in comparison to general population. Few investigations have been performed to evaluate the independent effect of exercise on biochemical and clinical symptoms of patients with PCOS. The aim of the study was to find the effect of home base aerobic-strengthening exercises on anthropometric and hormonal variables of patients with PCOS.MaterialsandMethods:In this randomized controlled trial twenty women in the exercise group performed aerobic, strengthening exercises; the other 20 participants in the control group were advised to continue their previous physical activity pattern. Blood pressure, Waist to Hip ratio (WHR, BMI along with hormonal variables(including insulin related factors, sexual hormones and inflammatory factors were assessed at baselineand after the 12 week intervention.Results:16patients in the exercise group and 14 patients in control group finished the study. TheWHR (p<0.001 along with the blood level of insulin (p=0.016, FBS (p=0.044, Prolactine (p=0.022 and hsCRP (p=0.035 and HOMA index (p=0.009 were decreased significantly in the exercise group compared with the control group. No significant differences were found in lipid profile and sexual hormones between groups at the end of the study.Conclusion:We can conclude that 12 weeks combined aerobic-strengthening exercise program in women with poly cystic ovary syndrome can lead to a reduction of waist to hip ratio (WHR and some cardiovascular risk factors (including insulin, FBS, HOMA index and HsCRP along with an increase of prolactine level in these patients.

  18. Blindness

    Science.gov (United States)

    ... good vision would be able to read certain letters from 20 feet (6 meters) away. Eyesight this good is called 20/20 vision, although some people can see even better than that. The numbers change depending on ...

  19. Top-down influence on the visual cortex of the blind during sensory substitution

    Science.gov (United States)

    Murphy, Matthew C.; Nau, Amy C.; Fisher, Christopher; Kim, Seong-Gi; Schuman, Joel S.; Chan, Kevin C.

    2017-01-01

    Visual sensory substitution devices provide a non-surgical and flexible approach to vision rehabilitation in the blind. These devices convert images taken by a camera into cross-modal sensory signals that are presented as a surrogate for direct visual input. While previous work has demonstrated that the visual cortex of blind subjects is recruited during sensory substitution, the cognitive basis of this activation remains incompletely understood. To test the hypothesis that top-down input provides a significant contribution to this activation, we performed functional MRI scanning in 11 blind (7 acquired and 4 congenital) and 11 sighted subjects under two conditions: passive listening of image-encoded soundscapes before sensory substitution training and active interpretation of the same auditory sensory substitution signals after a 10-minute training session. We found that the modulation of visual cortex activity due to active interpretation was significantly stronger in the blind over sighted subjects. In addition, congenitally blind subjects showed stronger task-induced modulation in the visual cortex than acquired blind subjects. In a parallel experiment, we scanned 18 blind (11 acquired and 7 congenital) and 18 sighted subjects at rest to investigate alterations in functional connectivity due to visual deprivation. The results demonstrated that visual cortex connectivity of the blind shifted away from sensory networks and toward known areas of top-down input. Taken together, our data support the model of the brain, including the visual system, as a highly flexible task-based and not sensory-based machine. PMID:26584776

  20. Top-down influence on the visual cortex of the blind during sensory substitution.

    Science.gov (United States)

    Murphy, Matthew C; Nau, Amy C; Fisher, Christopher; Kim, Seong-Gi; Schuman, Joel S; Chan, Kevin C

    2016-01-15

    Visual sensory substitution devices provide a non-surgical and flexible approach to vision rehabilitation in the blind. These devices convert images taken by a camera into cross-modal sensory signals that are presented as a surrogate for direct visual input. While previous work has demonstrated that the visual cortex of blind subjects is recruited during sensory substitution, the cognitive basis of this activation remains incompletely understood. To test the hypothesis that top-down input provides a significant contribution to this activation, we performed functional MRI scanning in 11 blind (7 acquired and 4 congenital) and 11 sighted subjects under two conditions: passive listening of image-encoded soundscapes before sensory substitution training and active interpretation of the same auditory sensory substitution signals after a 10-minute training session. We found that the modulation of visual cortex activity due to active interpretation was significantly stronger in the blind over sighted subjects. In addition, congenitally blind subjects showed stronger task-induced modulation in the visual cortex than acquired blind subjects. In a parallel experiment, we scanned 18 blind (11 acquired and 7 congenital) and 18 sighted subjects at rest to investigate alterations in functional connectivity due to visual deprivation. The results demonstrated that visual cortex connectivity of the blind shifted away from sensory networks and toward known areas of top-down input. Taken together, our data support the model of the brain, including the visual system, as a highly flexible task-based and not sensory-based machine.

  1. Altered White Matter Integrity in the Congenital and Late Blind People

    Directory of Open Access Journals (Sweden)

    Dawei Wang

    2013-01-01

    Full Text Available The blind subjects have experienced a series of brain structural and functional alterations due to the visual deprivation. It remains unclear as to whether white matter changes differ between blind subjects with visual deprivation before and after a critical developmental period. The present study offered a direct comparison in changes of white matter fractional anisotropy (FA between congenital blind (CB and late blind (LB individuals. Twenty CB, 21 LB (blindness onset after 18 years old, and 40 sight control (SC subjects were recruited. Both the tract-based spatial statistics (TBSS and voxel-based analysis (VBA showed lower FA in the bilateral optic radiations in both blind groups, suggesting that the loss of white matter integrity was the prominent hallmark in the blind people. The LB group showed more extensive white matter impairment than the CB group, indicating the mechanisms of white matter FA changes are different between the CB and LB groups. Using a loose threshold, a trend of an increased FA was found in the bilateral corticospinal tracts in the LB but with a smaller spatial extent relative to the CB. These results suggest that white matter FA changes in the blind subjects are the reflection of multiple mechanisms, including the axonal degeneration, deafferentation, and plasticity.

  2. The Cost of Blindness in the Republic of Ireland 2010–2020

    Directory of Open Access Journals (Sweden)

    D. Green

    2016-01-01

    Full Text Available Aims. To estimate the prevalence of blindness in the Republic of Ireland and the associated financial and total economic cost between 2010 and 2020. Methods. Estimates for the prevalence of blindness in the Republic of Ireland were based on blindness registration data from the National Council for the Blind of Ireland. Estimates for the financial and total economic cost of blindness were based on the sum of direct and indirect healthcare and nonhealthcare costs. Results. We estimate that there were 12,995 blind individuals in Ireland in 2010 and in 2020 there will be 17,997. We estimate that the financial and total economic costs of blindness in the Republic of Ireland in 2010 were €276.6 million and €809 million, respectively, and will increase in 2020 to €367 million and €1.1 billion, respectively. Conclusions. Here, ninety-eight percent of the cost of blindness is borne by the Departments of Social Protection and Finance and not by the Department of Health as might initially be expected. Cost of illness studies should play a role in public policy making as they help to quantify the indirect or “hidden” costs of disability and so help to reveal the true cost of illness.

  3. The effectiveness and safety of topical PhotoActif phosphatidylcholine-based anti-cellulite gel and LED (red and near-infrared) light on Grade II-III thigh cellulite: a randomized, double-blinded study.

    Science.gov (United States)

    Sasaki, Gordon H; Oberg, Kerby; Tucker, Barbara; Gaston, Margaret

    2007-06-01

    Cellulite of the upper lateral and posterior thighs and lower buttocks represents a common, physiological and unwanted condition whose etiologies and effective management are subjects of continued debate. The purpose of this controlled, double-blinded study is to evaluate the efficacy and safety of a novel phosphatidylcholine-based, cosmeceutical anti-cellulite gel combined with a light-emitting diode (LED) array at the wavelengths of red (660 nm) and near-infrared (950 nm), designed to counter the possible mechanisms that purportedly accentuate the presence of thigh cellulite. Nine healthy female volunteers with Grade II-III thigh cellulite were randomly treated twice daily with an active gel on one thigh and a placebo gel on the control thigh for 3 months. Twice weekly, each thigh was exposed for a 15-minute treatment with LED light for a total of 24 treatments. At 0, 6, and 12 weeks of the study the following clinical determinants were obtained: standardized digital photography, height and weight measurements, standardized thigh circumference tape measurements, pinch testing, body mass index (kg/m2), body fat analysis (Futrex-5500/XL near-infrared analyzer), and digital high-resolution ultrasound imaging of the dermal-adiposal border. In selected patients, full-thickness biopsies of the placebo and active-treated sites were obtained. At 18 months, repeat standardized digital photography, height and weight measurements, and body mass index measurements were obtained. At the end of 3 months, eight of nine thighs treated with the phosphatidylcholine-based, anti-cellulite gel and LED treatments were downgraded to a lower cellulite grade by clinical examination, digital photography, and pinch test assessment. Digital ultrasound at the dermal-adiposal interface demonstrated not only a statistically significant reduction of immediate hypodermal depth, but also less echo-like intrusions into the dermal layer. Three of six biopsies from thighs treated for 3 months with

  4. Color blindness among multiple sclerosis patients in Isfahan.

    Science.gov (United States)

    Shaygannejad, Vahid; Golabchi, Khodayar; Dehghani, Alireza; Ashtari, Fereshteh; Haghighi, Sepehr; Mirzendehdel, Mahsa; Ghasemi, Majid

    2012-03-01

    Multiple sclerosis (MS) is a disease of young and middle aged individuals with a demyelinative axonal damage nature in central nervous system that causes various signs and symptoms. As color vision needs normal function of optic nerve and macula, it is proposed that MS can alter it via influencing optic nerve. In this survey, we evaluated color vision abnormalities and its relationship with history of optic neuritis and abnormal visual evoked potentials (VEPs) among MS patients. The case group was included of clinically definitive MS patients and the same number of normal population was enrolled as the control group. Color vision of all the participants was evaluated by Ishihara test and then visual evoked potential (VEPs) and history of optic neuritis (ON) was assessed among them. Then, frequency of color blindness was compared between the case and the control group. Finally, color blinded patients were compared to those with the history of ON and abnormal VEPs. 63 MS patients and the same number of normal populations were enrolled in this study. 12 patients had color blindness based on the Ishihara test; only 3 of them were among the control group, which showed a significant different between the two groups (P = 0.013). There was a significant relationship between the color blindness and abnormal VEP (R = 0.53, P = 0.023) but not for the color blindness and ON (P = 0.67). This study demonstrates a significant correlation between color blindness and multiple sclerosis including ones with abnormal prolonged VEP latencies. Therefore, in individuals with acquired color vision impairment, an evaluation for potentially serious underlying diseases like MS is essential.

  5. Designing Motion Gesture Interfaces in Mobile Phones for Blind People

    Institute of Scientific and Technical Information of China (English)

    任向实

    2014-01-01

    Despite the existence of advanced functions in smartphones, most blind people are still using old-fashioned phones with familiar layouts and dependence on tactile buttons. Smartphones support accessibility features including vibration, speech and sound feedback, and screen readers. However, these features are only intended to provide feedback to user commands or input. It is still a challenge for blind people to discover functions on the screen and to input the commands. Although voice commands are supported in smartphones, these commands are difficult for a system to recognize in noisy environments. At the same time, smartphones are integrated with sophisticated motion sensors, and motion gestures with device tilt have been gaining attention for eyes-free input. We believe that these motion gesture interactions offer more efficient access to smartphone functions for blind people. However, most blind people are not smartphone users and they are aware of neither the affordances available in smartphones nor the potential for interaction through motion gestures. To investigate the most usable gestures for blind people, we conducted a user-defined study with 13 blind participants. Using the gesture set and design heuristics from the user study, we implemented motion gesture based interfaces with speech and vibration feedback for browsing phone books and making a call. We then conducted a second study to investigate the usability of the motion gesture interface and user experiences using the system. The findings indicated that motion gesture interfaces are more efficient than traditional button interfaces. Through the study results, we provided implications for designing smartphone interfaces.

  6. Color blindness among multiple sclerosis patients in Isfahan

    Directory of Open Access Journals (Sweden)

    Vahid Shaygannejad

    2012-01-01

    Full Text Available Background: Multiple sclerosis (MS is a disease of young and middle aged individuals with a demyelinative axonal damage nature in central nervous system that causes various signs and symptoms. As color vision needs normal function of optic nerve and macula, it is proposed that MS can alter it via influencing optic nerve. In this survey, we evaluated color vision abnormalities and its relationship with history of optic neuritis and abnormal visual evoked potentials (VEPs among MS patients. Materials and Methods: The case group was included of clinically definitive MS patients and the same number of normal population was enrolled as the control group. Color vision of all the participants was evaluated by Ishihara test and then visual evoked potential (VEPs and history of optic neuritis (ON was assessed among them. Then, frequency of color blindness was compared between the case and the control group. Finally, color blinded patients were compared to those with the history of ON and abnormal VEPs. Results: 63 MS patients and the same number of normal populations were enrolled in this study. 12 patients had color blindness based on the Ishihara test; only 3 of them were among the control group, which showed a significant different between the two groups (P = 0.013. There was a significant relationship between the color blindness and abnormal VEP (R = 0.53, P = 0.023 but not for the color blindness and ON (P = 0.67. Conclusions: This study demonstrates a significant correlation between color blindness and multiple sclerosis including ones with abnormal prolonged VEP latencies. Therefore, in individuals with acquired color vision impairment, an evaluation for potentially serious underlying diseases like MS is essential.

  7. 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 from....... This may help practitioners and researchers new to the area of convolutive source separation obtain a complete overview of the field. Hopefully those with more experience in the field can identify useful tools, or find inspiration for new algorithms....

  8. 弱盲签名方案的构造的一种新方法%A New Method of Constructing Weak Blind Digital Signature Schemes

    Institute of Scientific and Technical Information of China (English)

    杜伟章; 陈克非

    2003-01-01

    In this paper, by integrating blind parameter digital signature schemes and the existing weak blind digital signature schemes,on the basis of generalized ElGamal type digital signature schemes,we construct some new weak blind digital signature schemes based on discrete logarithms. We check and analyze these digital signature schemes also.

  9. A Rare Hydrocephalus Complication: Cortical Blindness.

    Science.gov (United States)

    Ünal, Emre; Göçmen, Rahşan; Işıkay, Ayşe İlksen; Tekşam, Özlem

    2015-01-01

    Cortical blindness related to bilateral occipital lobe infarction is an extremely rare complication of hydrocephalus. Compression of the posterior cerebral artery, secondary to tentorial herniation, is the cause of occipital infarction. Particularly in children and mentally ill patients, cortical blindness may be missed. Therefore, early diagnosis and treatment of hydrocephalus is important. We present herein a child of ventricular shunt malfunction complicated by cortical blindness.

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

    Institute of Scientific and Technical Information of China (English)

    陈杰; 尚丽; 孙站里

    2015-01-01

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

  11. Concept mapping for virtual rehabilitation and training of the blind.

    Science.gov (United States)

    Sanchez, Jaime; Flores, Hector

    2010-04-01

    Concept mapping is a technique that allows for the strengthening of the learning process, based on graphic representations of the learner's mental schemes. However, due to its graphic nature, it cannot be utilized by learners with visual disabilities. In response to this limitation we implemented a study that involves the design of AudiodMC, an audio-based, virtual environment for concept mapping designed for use by blind users and aimed at virtual training and rehabilitation. We analyzed the stages involved in the design of AudiodMC from a user-centered design perspective, considering user involvement and usability testing. These include an observation stage to learn how blind learners construct conceptual maps using concrete materials, a design stage to design of a software tool that aids blind users in creating concept maps, and a cognitive evaluation stage using AudiodMC. We also present the results of a study implemented in order to determine the impact of the use of this software on the development of essential skills for concept mapping (association, classification, categorization, sorting and summarizing). The results point to a high level of user acceptance, having identified key sound characteristics that help blind learners to learn concept codification and selection skills. The use of AudiodMC also allowed for the effective development of the skills under review in our research, thus facilitating meaningful learning.

  12. Causes of blindness and needs of the blind in Mansoura, Egypt.

    Science.gov (United States)

    el-Gilany, A H; el-Fedawy, S; Tharwat, M

    2002-01-01

    A study of 113 blind people in Mansoura, Egypt highlighted the causes and risk factors for blindness, and health and social care needs of the blind. In two-thirds of cases, blindness occurred before 10 years of age. Risk factors for blindness were reported by more than half the study population. Congenital causes accounted for almost half the cases. The commonest causes of bilateral blindness were corneal opacities, cataract and glaucoma. Almost three-quarters of causes were avoidable. Health and social care for this group was inadequate and more than half would benefit from further management. Legislation for keratoplasty, a registry of blind people, and a nationwide community survey on the epidemiology of blindness are needed urgently.

  13. Congenital color blindness in young Turkish men.

    Science.gov (United States)

    Citirik, Mehmet; Acaroglu, Golge; Batman, Cosar; Zilelioglu, Orhan

    2005-04-01

    We investigated a healthy population of men from different regions of Turkey for the presence of congenital red-green color blindness. Using Ishihara pseudoisochromatic plates, 941 healthy men from the Turkish army were tested for congenital red-green color blindness. The prevalence of red-green color blindness was 7.33 +/- 0.98% (5.10% protans and 2.23% deutans). These ratios were higher than other reported samples from Mediterranean Europe. Higher percentages of color blindness were found in regions with a lower education level and more consanguineous marriages.

  14. 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.

  15. 基于圆锥曲面反射映射的彩色图像盲水印方法%Blind color image watermarking method based on conic surface and reflection

    Institute of Scientific and Technical Information of China (English)

    李岩山; 曹文明

    2011-01-01

    讨论了Clifford代数中反射映射和旋转的性质和三维Clifford空间中彩色图像的Clifford傅里叶变换的特点,构造了彩色图像水印圆锥曲面,并证明了水印圆锥曲面应用于彩色图像水印的可行性;提出基于圆锥曲面反射映射的彩色图像盲水印方法,该方法运用简单直观的Clifford反射映射将水印信息嵌入到原始图像中,且水印提取不需要原始图像.实验结果显示,该方法能较好地抵抗多种滤波、加噪、旋转、剪切等攻击,是一种行之有效的彩色图像盲水印方法.%This paper introduced the properties of reflection and rotation in Clifford algebra and discussed some useful characteristics of the Clifford Fourier transform of the color image in 3D Clifford algebra space. In order to add watermark effectively,firstly structured a conic surface of the color image watermarking and proved the feasibility of using it to the color image watermarking. Then proposed the blind color image watermarking method based on the conic surface and reflection, which used the theory of the reflection in Clifford algebra to add the watermark to the color image, and got the watermark from the marked image without the original image. The result of the experiment shows the algorithm has good performance of the resistance to the attack of many filtering, noise, rotation and cutting, and is an effective method.

  16. A prospective, randomized, double-blind, placebo-controlled parallel-group dual site trial to evaluate the effects of a Bacillus coagulans-based product on functional intestinal gas symptoms

    Science.gov (United States)

    2009-01-01

    Background This randomized double blind placebo controlled dual site clinical trial compared a probiotic dietary supplement to placebo regarding effects on gastrointestinal symptoms in adults with post-prandial intestinal gas-related symptoms (abdominal pain, distention, flatulence) but no gastrointestinal (GI) diagnoses to explain the symptoms. Methods Sixty-one adults were enrolled (age 36.5 ± 12.6 years; height 165.1 ± 9.2 cm; weight 75.4 ± 17.3 kg) and randomized to either Digestive Advantage™ Gas Defense Formula - (GanedenBC30 Bacillus coagulans GBI-30, 6086): n = 30; or Placebo: n = 31. Study subjects were evaluated every two weeks over a four-week period using validated questionnaires and standard biochemical safety testing. Outcome criteria of interest included change from baseline in Gastrointestinal Symptom Rating Scale (GSRS) abdominal pain, abdominal distention, flatus, and the Severity of Dyspepsia Assessment (SODA) bloating and gas subscores over four weeks of product use. Results Measured against the placebo, subjects in the probiotic group achieved significant improvements in GSRS abdominal pain subscore (p = 0.046) and the GSRS total score (p = 0.048), with a strong trend for improvement on the GSRS abdominal distension subscore (p = 0.061). A strong placebo effect was evident which could explain the lack of statistical significant differences between the groups for many of the efficacy variables. Conclusion In conclusion, the Bacillus coagulans-based product was effective in improving the quality of life and reducing gastrointestinal symptoms in adults with post prandial intestinal gas-related symptoms and no GI diagnoses. Trial Registration ClinicalTrials.gov Identifier: NCT00881322 PMID:19922649

  17. A prospective, randomized, double-blind, placebo-controlled parallel-group dual site trial to evaluate the effects of a Bacillus coagulans-based product on functional intestinal gas symptoms

    Directory of Open Access Journals (Sweden)

    Feldman Samantha

    2009-11-01

    Full Text Available Abstract Background This randomized double blind placebo controlled dual site clinical trial compared a probiotic dietary supplement to placebo regarding effects on gastrointestinal symptoms in adults with post-prandial intestinal gas-related symptoms (abdominal pain, distention, flatulence but no gastrointestinal (GI diagnoses to explain the symptoms. Methods Sixty-one adults were enrolled (age 36.5 ± 12.6 years; height 165.1 ± 9.2 cm; weight 75.4 ± 17.3 kg and randomized to either Digestive Advantage™ Gas Defense Formula - (GanedenBC30 Bacillus coagulans GBI-30, 6086: n = 30; or Placebo: n = 31. Study subjects were evaluated every two weeks over a four-week period using validated questionnaires and standard biochemical safety testing. Outcome criteria of interest included change from baseline in Gastrointestinal Symptom Rating Scale (GSRS abdominal pain, abdominal distention, flatus, and the Severity of Dyspepsia Assessment (SODA bloating and gas subscores over four weeks of product use. Results Measured against the placebo, subjects in the probiotic group achieved significant improvements in GSRS abdominal pain subscore (p = 0.046 and the GSRS total score (p = 0.048, with a strong trend for improvement on the GSRS abdominal distension subscore (p = 0.061. A strong placebo effect was evident which could explain the lack of statistical significant differences between the groups for many of the efficacy variables. Conclusion In conclusion, the Bacillus coagulans-based product was effective in improving the quality of life and reducing gastrointestinal symptoms in adults with post prandial intestinal gas-related symptoms and no GI diagnoses. Trial Registration ClinicalTrials.gov Identifier: NCT00881322

  18. Efficacy of wheat-based biscuits fortified with microcapsules containing ferrous sulfate and potassium iodate or a new hydrogen-reduced elemental iron: a randomised, double-blind, controlled trial in Kuwaiti women.

    Science.gov (United States)

    Biebinger, Ralf; Zimmermann, Michael B; Al-Hooti, Suad N; Al-Hamed, Nawal; Al-Salem, Ebtehal; Zafar, Tasleem; Kabir, Yearul; Al-Obaid, I'nam; Petry, Nicolai; Hurrell, Richard F

    2009-11-01

    Adverse sensory changes prevent the addition of highly bioavailable ferrous sulfate (FeSO4) to most wheat flours. Poorly absorbable reduced Fe powders are commonly used. Encapsulation of FeSO4 can overcome these sensory changes, but the particle size of commercial compounds is too large to be used by flour mills. The first objective of the study was to measure the efficacy in wheat flour of two newly developed Fe compounds, an H-reduced Fe powder (NutraFine RS; North America Höganäs High Alloys LLC, Johnstown, PA, USA) and small particle-sized (40 microm) encapsulated FeSO4. As a second objective, the microcapsules were evaluated as a vehicle for iodine fortification. A randomised, double-blind controlled intervention trial was conducted in Kuwaiti women (n 279; aged 18-35 years) with low body Fe stores (serum ferritin (SF) < 25 microg/l) randomly assigned to one of three groups (20 mg Fe as NutraFine RS, 10 mg Fe as encapsulated FeSO4 and 150 microg iodine, or no fortification Fe) who consumed wheat-based biscuits 5 d per week. At baseline and 22 weeks, Hb, SF, transferrin receptor, urinary iodine and body Fe stores were measured. Relative to control, mean SF in the encapsulated FeSO4 group increased by 88 % (P < 0.001) and body Fe stores increased from - 0.96 to 2.24 mg/kg body weight (P < 0.001), while NutraFine RS did not significantly increase SF or body Fe stores. The median urinary iodine concentration increased from 140 to 213 microg/l (P < 0.01). NutraFine RS added at double the amount of Fe as FeSO4 was not efficacious in improving Fe status. The newly developed microcapsules were highly efficacious in improving both Fe stores and iodine status.

  19. Determining daylight and view preferences from the use of blinds in apartments

    DEFF Research Database (Denmark)

    Petersen, Mads Dines

    2015-01-01

    Present research focuses on the use of blinds and curtains in apartments and inhabitants’ operation of them. The objective of the present research is to develop a better understanding of how curtains and blinds are operated by the inhabitants in apartments and the possible consequences it has...... that curtains or blinds, often close off new apartment buildings with large glass areas in dense urban context. Such observations indicate that there can be a discrepancy between the intentions of the design team or architect and the perception of the user. The paper presents the results of observations...... facades in the same building there is no indication of curtains and blinds being operated based on daylight. However, it appears that view and context plays a significant part in the use of blinds. Furthermore, it appears that the amount of traffic and the perception of privacy plays a role...

  20. Childhood Fears among Children Who Are Blind: The Perspective of Teachers Who Are Blind

    Science.gov (United States)

    Al-Zboon, Eman

    2017-01-01

    The aim of this study was to investigate childhood fears in children who are blind from the perspective of teachers who are blind. The study was conducted in Jordan. Forty-six teachers were interviewed. Results revealed that the main fear content in children who are blind includes fear of the unknown; environment-, transportation- and…