Improving discriminability among acoustically similar words bymodified distance metric

In a template-matching based speech recognition system excessive weight given to perceptually unimportant spectral variations is undesirable for discriminating among acoustically similar words. By introducing a simple threshold-type nonlinearity applied to the distance metric, the word recognition performance can be improved for a vocabulary with similar sounding words, without modifying the system structure     

Adaptive low-power address encoding techniques using self-organizing lists

Off-chip bus transitions are a major source of power dissipation for embedded systems. In this paper, new adaptive encoding schemes are proposed that significantly reduce transition activity on data and multiplexed address buses. These adaptive techniques are based on self-organizing lists to achieve reduction in transition activity by exploiting the spatial and temporal locality of the addresses. Also the proposed techniques do not require any extra bit lines and have minimal delay overhead. The techniques are evaluated for efficiency using a wide variety of application programs including SPEC 95 benchmark set. Unlike previous approaches that focus on instruction address buses, experiments demonstrate significant reduction in transition activity of up to 54% in data address buses and up to 59% in multiplexed address buses. The average reductions are twice those obtained using current schemes on a data address bus and more than twice those obtained on a multiplexed address bus.     

利用FreeBSD构建安全网络

1 FreeBSD FreeBSD是BSD Unix的一个继承者,是一个完全免费的操作系统.从FreeBSD的起源和发展过程可以看出,FreeBSD是一种自由的Unix操作系统,它是由计算机科学家、软件工程师等志愿者通过Internet合作开发的,目的是为所有的使用者提供没有任何附加条件的自由的Unix操作系统.     

Speaker-independent isolated word recognition using multiple hiddenMarkov models

A multi-HMM speaker-independent isolated word recognition system is described. In this system, three vector quantisation methods, the LBG algorithm, the EM algorithm, and a new MGC algorithm, are used for the classification of the speech space. These quantisations of the speech space are then used to produce three HMMs for each word in the vocabulary. In the recognition step, the Viterbi algorithm is used in the three subrecognisers. The log probabilities of the observation sequences matching-the models are multiplied by the weights determined by the recognition accuracies of individual subrecognisers and summed to give the log probability that the utterance is of a particular word in the vocabulary. This multi-HMM system results in a reduction of about 50% in the error rate in comparison with the single model system     

变体上下文窗口下的词向量准确性研究

词向量的准确性在较大程度上影响了这些自然语言处理任务的运行。词向量通过词嵌入产生,在词嵌入的方法中,都将目标单词及其上下文作为训练的输入,因此上下文的选定对词嵌入有着重要的影响。文中通过使用word2vec词嵌入方法,研究各种变体上下文窗口对词嵌入准确度的影响。根据上下文窗口的各种宽度、偏移量、权值进行了一系列实验。从实验结果中发现,上下文窗口的变化只会对整体训练结果的准确性造成很小的影响,然而对于其中具体的各个单词却有显著影响。从而得出结论,即大量单词各自所适应的上下文窗口区别较大,而统一的上下文窗口难以实现对全部单词的最佳训练。     

利用PXE技术组建无盘Win98工作站

介绍利用PXE技术组建无盘windows 98局域网的步骤。重点讲述一种不要PXEB00TROM芯片，而是将PXE启动代码写入BIOS的组网方法和建网中应重点注意的问题。     

Constructing cylindrical panoramic image using equidistant matching

An efficient algorithm for constructing cylindrical panoramic image mosaics from a near pure panning camera is proposed. The algorithm uses equidistant matching for image alignment which uses a translational motion model. It also allows the effective focal length of the camera to be estimated efficiently by a bisection method     

New scheme for underwater acoustically wireless transmission using direct sequence code division multiple access in MIMO systems

Wireless Networks - This paper proposes a new technique based on Direct Sequence Code Division Multiple Access for underwater acoustically wireless transmission with excessive transmission rate....     

Video denoising using shape-adaptive sparse representation over similar spatio-temporal patches

We present an effective patch-based video denoising algorithm that exploits both local and nonlocal correlations. The method groups 3D shape-adaptive patches, whose surrounding cubic neighborhoods along spatial and temporal dimensions have been found similar by patch clustering. Such grouping results in 4D data structures with arbitrary shapes. Since the obtained 4D groups are highly correlated along all the dimensions, they can be represented very sparsely with a 4D shape-adaptive DCT. The noise can be effectively attenuated by transform shrinkage. Experimental results on a wide range of videos show that this algorithm provides significant improvement over the state-of-the-art denoising algorithms in terms of both objective metric and subjective visual quality.     

利用完备差集构造QC-LDPC码

针对准循环低密度奇偶校验( QC-LDPC)码中循环置换矩阵的移位次数的确定问题,提出了一种利用组合设计中完备差集( PDF)构造QC-LDPC码的新颖方法。当循环置换矩阵的维度大于一定值时,该方法所构造的规则QC-LDPC码围长至少为6,具有灵活选择码长和码率的优点,且所需的存储空间更少,降低了硬件实现的复杂度。仿真结果表明：在误码率为10-5时,所构造的码率为3/4的PDF-QC-LDPC(3136,2352)与基于最大公约数(GCD)构造的GCD-QC-LDPC(3136,2352)码和基于循环差集(CDF)构造的CDF-QC-LDPC(3136,2352)码相比,其净编码增益(NCG)分别有0.41 dB和0.32 dB的提升;且在码率为4/5时,所构造的PDF-QC-LDPC (4880,3584)码比GCD-QC-LDPC(4880,3584)码和CDF-QC-LDPC(4880,3584)码的NCG分别改善了0.21 dB和0.13 dB。     

Constructing and decoding GWBE codes using Kronecker products

In this letter, we introduce a novel method for constructing large size Generalized Welch Bound Equality (GWBE) matrices. This method can also be used for the construction of large WBE matrices. The advantage of this method is its low complexity for constructing large size matrices and low computational complexity using Maximum Likelihood (ML) decoders for a subclass of these codes.     

支持词形词义模糊检索的可搜索加密算法

采用倒排索引结构建立安全索引文件,以支持文件动态更新,利用WordNet接口对关键词词义拓展,构造词形模糊集与词义模糊集,给出一种满足用户在云计算环境中对密文数据进行词形和词义模糊检索需求的可搜索加密算法DSFS。分析表明DSFS算法是CKA2安全的,真实数据集的测试结果表明,与已有可搜索加密算法相比,DSFS算法获得较全面的检索结果、检索速度更快。     

基于Trie树的词语左右熵和互信息新词发现算法

由于大量新词的出现,使得中文文本分析产生了较大的困难,因此新词发现成为目前中文自然语言处理中的热点和难点问题。为此,文中提出了一种基于Trie树的词语左右熵和互信息新词发现算法。先根据成词规则,筛选掉文本中的停用词和非中文字符,将每个字与其右邻的字组成二元组;然后利用左右信息熵和互信息进行成词概率的计算,根据计算到的成词概率和词频筛选出新词;并且设计了三个实验,验证了算法的有效性和可行性。实验结果表明,该新词发现算法成词准确率较高,比其他新词发现算法时间效率有较大的提高,对于中文分词结果的优化起到重要的作用。     

Fast full search motion estimation algorithm using early detection of impossible candidate vectors

To reduce the amount of computations for a full search (FS) algorithm for fast motion estimation, we propose a new and fast FS motion estimation algorithm. The computational reduction of our FS motion estimation algorithm comes from fast elimination of impossible motion vectors. We obtain faster elimination of inappropriate motion vectors using efficient matching units from localization of a complex area in image data. In this paper, we show three properties in block matching of motion estimation. We suggest two fast matching scan algorithms: one from adaptive matching scan and the other from fixed dithering order. Experimentally, we remove the unnecessary computations by about 30% with our proposed algorithm compared with the conventional fast FS algorithms.     

Constructing a videophone for the hearing impaired using MPEG-4tools

The Lip Telephone is a special videoconferencing system built by the authors with tools provided by the MPEG-4 audio-visual standard. The videophone achieves high-fidelity representation in the area of the speaker's mouth, letting lip readers communicate over a standard telephone connection or the Internet     

Some candidate atoms and ions for frequency standards research using laser radiative cooling techniques

The rapid progress in laser atomic cooling ideas and also in laser spectral coverage and frequency stabilization make it appropriate to reexamine the periodic table for atoms and ions that may be of special interest for radiatively-cooled frequency standards research. We discuss Hg⁺, Pb⁺, Ba⁺, neutral alkalis, Mg, Ca, and Ag. Optical two-photon and weak single-photon transitions are represented, along with microwave hfs and fs transitions.     

Detection of subsurface rocks in sand of similar composition using a millimeter wave imaging system

The ability to image objects, whether natural or man made, beneath soil is extremely beneficial. The detection scenario becomes increasingly difficult when the object and the soil are composed of the same material, as in the detection of subsurface rocks. The feasibility of detecting rock in similar composition is explored. An active multi-spectral millimeter wave (mmW) imaging system operating from 90–140 GHz is used to detect lava rock buried beneath lava sand at various depths, up to a limit of 64 mm. The principal component analysis method was used in the data processing.     

一种使用边缘增强技术提高相似图片检索召回率的方法

针对大规模图像分类处理中图像旋转或背景变换导致的配准度较低问题,提出一种基于边缘增强的卷积神经网络图像分类方法。该方法通过VGG19网络模型提取图像特征,并使用余弦相似度进行图像分类判定,利用边缘增强突出图像主体的边缘特征,降低图像旋转或背景变换对VGG19网络分类性能带来的影响。实验证明,该方法可以有效地提高同一主体旋转图像和背景变换图像与原始图像的相似度,适用于各类图像的分类。     

Constructing multirate CDMA signals with controlled peak-to-averagepower ratio using balanced incomplete block designs

A multirate modulation scheme with controlled peak-to-average power (PAV) ratio and suitable for code division multiple access techniques is introduced. The scheme utilizes codes drawn from a fixed set of Walsh-Hadamard codes but other code families can also be used. The strategy employs balanced incomplete block designs to define the multirate data symbols, with the objective being to reduce depletion of the code pool while controlling the PAV ratio. Existing multirate schemes are reviewed. Code depletion and PAV ratio characteristics of the proposed scheme are compared to existing schemes. Symbol error performance of the proposed scheme in an additive white Gaussian noise channel is examined. It is concluded that the proposed scheme, unlike the two other existing schemes that are examined, strikes a good balance between PAV ratio, code depletion, and error performance