查看更多>>摘要：Range reduction is the initial and essential stage of function computation,but its pipelined implementation has the drawbacks of large cost and terrible accuracy.We proposed low cost and accurate pipelined range reduction,which adopts truncated multiplier with optimized bit-width to reduce the cost of pipelined implementation and achieve the accuracy within 1 unit in the last place (ulp).TCORDIC algorithm is a widely used algorithm to compute floating-point sine/cosine function,and we implemented the combination of TCORDIC and our range reduction algorithms,verifying the goal of accuracy within 1 ulp.
查看更多>>摘要：Compared with the method by Zhang in 2017,an extended one for constructing Boolean functions with multiple-valued Walsh spectra is given,which is derived from a bent function by complementing the values at some points.Based on which,new classes of Boolean functions with four-valued and five-valued Walsh spectra are presented,and some of their cryptographic properties are studied.
查看更多>>摘要：With the popularity of mobile terminals,Quick response (QR) code,which acts as a convenient and quick way to transfer graphic information,has been widely used in various fields.QR code is a 2D matrix code which contains information in both vertical and horizontal directions.In order to promote the characters encoding efficiency,we propose the improved character encoding methods based on QR code.Specifically,we divide the types of encoding data into Chinese characters and non-Chinese characters,and thus optimizing their encoding methods separately: we apply the branch-bound algorithm to optimize the encoding pattern selection of QR code;as for Chinese characters,based on the Chinese characters use frequency generated by Url crawler system,we design a new encoding method for Chinese characters.Our approach has been shown to afford better experimental test results compared with traditional encoding methods of QR code.
查看更多>>摘要：As one of the most commonly used features,Mel-frequency cepstral coefficients (MFCCs) are less discriminative at high frequency.A novel technique,known as Deep scattering spectrum (DSS),addresses this issue and looks to preserve greater details.DSS feature has shown promise both on classification and recognition tasks.In this paper,we extend the use of DSS feature for acoustic scene classification task.Results on Detection and classification of acoustic scenes and events (DCASE) 2016 and 2017 show that DSS provided 4.8％ and 17.4％ relative improvements in accuracy over MFCC features,within a state-of-the-art time delay neural network framework.
查看更多>>摘要：Most of the existed vein features are lack of robustness to light intensity variation,and some algorithms rely on the specified vein data sets,which leads to the limitation of real applications.To solve the problems,we propose a novel vein recognition algorithm based on Nonnegative matrix factorization (NMF) with double regularization terms.The innovations of our algorithm are mainly reflected in the following two aspects: in order to improve feature robustness,a novel feature mapping function is designed to map the initial Histogram of oriented gradient (HOG) feature to a new space;to enhance the recognition performance,an effective NMF model is presented,which not only reduces feature dimension,but also optimizes the feature sparsity and clustering property simultaneously.Experiments show that the proposed algorithm can achieve satisfactory results in terms of False rejection rate (FRR) and False acceptance rate (FAR),which indicates that our algorithm is valuable for other classification problems.
查看更多>>摘要：Inspired by the recent advances in generative networks,we propose a VAE-GAN based hashing framework for fast image retrieval.The method combines a Variational autoencoder (VAE) with a Generative adversarial network (GAN) to generate content preserving images for pairwise hashing learning.By accepting real image and systhesized image in a pairwise form,a semantic perserving feature mapping model is learned under a adversarial generative process.Each image feature vector in the pairwise is converted to a hash codes,which are used in a pairwise ranking loss that aims to preserve relative similarities on images.Extensive experiments on several benchmark datasets demonstrate that the proposed method shows substantial improvement over the state-of-the-art hashing methods.
查看更多>>摘要：This paper introduces an integrated approach to estimate the fetal heart rate from the abdominal Electrocardiogram (ECG) signal.Empirical mode decomposition (EMD) can decompose the fetal ECG signal into a set of intrinsic mode functions,which can be used as the indicator of the occurrence for the fetal heartbeats.The decomposition basis functions are directly derived from the fetal signal under test,which make the detection process robust and adaptive.Multiple signal classification (MUSIC) is a high resolution algorithm for frequency estimation,which can be applied to the fetal heartbeats indicator sequence output from the preceding EMD,estimating the fetal heart rate in frequency domain without the heartbeat wave detection.Compared with the popular Independent component analysis (ICA) method,the proposed method has shown improved robustness and fidelity in estimation of the fetal heart rate during testing with real fetal ECG database from DaISy and PhysioNet.
查看更多>>摘要：Hashing for nearest neighbor search has attracted considerable interest recently given its efficiency in speed and storage.Many methods follow a projection-quantization framework which firstly projects original data into low-dimensional compact space and secondly quantifies each projected dimension to 1 bit by thresholding.The variance of projected dimensions,however,may vary a lot so that quantifying them equivalently degrades the searching performance.In this paper,we put forward a novel method,dubbed Balanced hashing (BH),which finds adjustment functions to reproject the data such that the variance of dimensions can be balanced by directly and explicitly maximizing the degree of balance of data,while preserving important properties.Experiments on benchmarks demonstrate that BH can outperform several state-of-the-art methods.
查看更多>>摘要：Nonlinear feedback shift registers (NFSRs) are widely used in communication and cryptography.How to construct more NFSRs with maximal periods,which can generate sequences with maximal periods,i.e.,de Brujin sequences,is an attractive problem.Recently many results on constructing de Bruijn sequences from adjacency graphs of Linear feedback shift registers (LFSRs) by means of the cycle joining method have been obtained.In this paper we discuss a class of LFSRs with characteristic polynomial p2(x),where p(x) is a primitive polynomial of degree n ≥ 2 over the finite field F2.As results,we determine their cycle structures and adjacency graphs,and further construct a class of new de Bruijn sequences from these LFSRs.
查看更多>>摘要：Focusing on the problem of state estimation in the presence of sensor faults and Out-of-sequence measurement (OOSM) observations synchronously,we derive a formulation of Linear minimum mean squared error (LMMSE) filter with the arbitrary time delay of OOSM,the generalization of the present work lies in simultaneous treatment of correlated faults together with OOSMs that arrive at an arbitrary delay in a linear-optimal manner.The approach is demonstrated in a numerical comparison.
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