Method of all-optical frequency encoded decimal to binary and binary coded decimal, binary to gray, and gray to binary data conversion using semiconductor optical amplifiers

Conversion of optical data from decimal to binary format is very important in optical computing and optical signal processing. There are many binary code systems to represent decimal numbers, the most common being the binary coded decimal (BCD) and gray code system. There are a wide choice of BCD codes, one of which is a natural BCD having a weighted code of 8421, by means of which it is possible to represent a decimal number from 0 to 9 with a combination of 4 bit binary digits. The reflected binary code, also known as the Gray code, is a binary numeral system where two successive values differ in only 1 bit. The Gray code is very important in digital optical communication as it is used to prevent spurious output from optical switches as well as to facilitate error correction in digital communications in an optical domain. Here in this communication, the author proposes an all-optical frequency encoded method of ":decimal to binary, BCD," "binary to gray," and "gray to binary" data conversion using the high-speed switching actions of semiconductor optical amplifiers. To convert decimal numbers to a binary form, a frequency encoding technique is adopted to represent two binary bits, 0 and 1. The frequency encoding technique offers advantages over conventional encoding techniques in terms of less probability of bit errors and greater reliability. Here the author has exploited the polarization switch made of a semiconductor optical amplifier (SOA) and a property of nonlinear rotation of the state of polarization of the probe beam in SOA for frequency conversion to develop the method of frequency encoded data conversion.     

Effects of binary encoding on pattern recognition and library matching of spectral data

Scott, D.R., 1988. Effects of binary encoding on pattern recognition and library matching of spectral data. Chemometrics and Intelligent Laboratory Systems, 4: 47–63.Binary encoding is frequently employed in pattern recognition studies and matching of unknown against library spectral data. In this study the effect of binary encoding on pattern recognition and library searches is determined using the Hamming and Euclidean distance metrics. The effect on a full intensity spectrum is to compress the total information into a qualitative spectral data vector, the most basic information in the full spectrum. Geometrically, binary encoding of unit normalized spectral data can be visualized as shifting spectral points on the faces of the measurement space hypercube to the corners of a Hamming hypercube. A new classification scheme for comparison of analytical spectra based on their binary encoded spectra is introduced. Quantitative expressions for the effect of binary encoding on general Euclidean distances between spectral points are derived and shown to depend upon their spectral classification. Generally binary encoding increases the interclass distances in pattern recognition and may decrease the intraclass distances. This effect is illustrated with a mass spectral pattern recognition example. The effect of binary encoding on library searches is to produce possible false compound identification in identity searches and to flag spectrally similar compounds in structure searches. A scheme which uses both the Hamming and the Euclidean metrics is proposed for improved library searches. This scheme is illustrated with searches of a small mass spectral library for benzene and p-dioxane spectra.     

符号M阵列结构光的编码研究

编码结构光的三维检测是一种主动视觉方法,通过投影仪投射一定的编码模式,获取匹配点,通过三角原理获得深度信息。为实现物体表面的快速测量,采用伪随机阵列对结构光进行编码。由于基于对角线法无法得到合适尺寸的 M阵列,研究一种能生成大尺寸 M阵列的算法,为提高测量的空间分辨率及测量精度奠定基础。在三元域中,使用单色光,选择条纹、圆圈和圆盘作为 M 阵列符号 ,符号容易识别和区分,并为解码图像搜索提供信息,提高对环境的抗干扰能力。大部分码字的汉明距离大于 3,具有更好的鲁棒性。实验结果验证了该方法的可行性和有效性。     

带约束二进制矩阵编码染色体及遗传算子设计

提出了一类带约束的二进制矩阵型染色体的编码方法.相对于传统向量型染色体编码方法而言,该方法可以通过在矩阵中设置"禁止位"将复杂优化问题的若干约束条件在编码中体现出来.此类染色体的交叉和变异操作不能采用传统方法,否则子代染色体可能成为问题的非法解.设计了一种针对此类型染色体的巡回变换操作,基于该操作可以实现用于带约束二进制矩阵编码染色体的交叉和变异算子.仿真实例表明,此类染色体及遗传算子的设计对于遗传算法用于复杂优化问题的求解,具有一定意义.     

多路激光跟踪干涉三维坐标测量系统冗余技术

介绍了冗余技术在多路激光跟踪干涉三维坐标测量系统中的应用。在分析激光跟踪干涉仪工作原理的基础上 ,采用 3 n[G]表决冗余方式 ,进行了系统的冗余设计。详细论述了基于系统的冗余技术实现的各种重大作用如系统的自标定、挡光自恢复和误差补偿等。最后指出冗余设计应当成为系统设计的一项重要原则     

Methods for automated manufacturability analysis of injection-molded and die-cast parts

In this article, a mathematical framework to automatically evaluate the manufacturability of injection-molded and die-cast parts is presented. The framework includes an implemented mathematical algorithm to solve key outstanding challenges in feature recognition for manufacturability analysis of injection-molded and die-cast parts. A novel feature recognition method is developed that is based on decomposing the part into elemental cubes and then, making use of their individual manufacturability, the manufacturability of the part as a whole is evaluated. This article discusses a procedure to obtain a 3D binary representation of the solid model and develops feature recognition techniques to extract critical manufacturability information from this 3D binary array. The outstanding challenges addressed by the method presented include the finding of parting surfaces, parting lines, undercuts, holes, bosses, and finding the direction of mold closure in the context of injection-molded or die-cast parts. The algorithm is implemented using a combination of C++ code and Unigraphics solid modeling software. A short example is presented.     

基于3D-CS混沌系统的双DNA编码图像加密算法

目的为解决加密算法中明文与混沌系统密钥关联小,且置乱扩散不能同步进行造成的安全性低的问题。在结合Chebyshev和Sine映射的基础上,新建三维Chebyshev-Sine混沌映射系统(3D-CS),提出一种基于3D-CS混沌系统的双DNA编码图像加密算法。方法设定二进制与四进制双重DNA编码,利用约瑟夫环变换对经过二进制DNA编码的图像RGB各层进行位置索引,同时完成置乱和扩散,然后将混沌系统产生的序列值经过处理后进行四进制DNA编码,最后将2种DNA序列进行加法运算后解码得到密文。结果仿真实验表明,索引序列和混沌序列通过了随机性检验,密文各层NPCR值分别为99.63%,99.61%,99.59%,UACI值分别为33.43%,33.44%,33.40%,信息熵分别为7.9992,7.9991,7.9993。结论所设计的混沌序列相较于其他混沌序列有一定优势,针对提出的问题有效提高了加密算法的安全性,密文能有效地抵御各种统计攻击与差分攻击。     

Distributed source coding using symbol-based and non-binary turbo codes - applications to wireless sensor networks

A simple but powerful scheme for distributed source coding (DSC) based on the concept of binning and syndromes and non traditional turbo codes is proposed. The previous works on the compression with side information using turbo codes and the binning technique are focused on binary turbo codes. The source is considered to be binary or is converted to a binary stream. This conversion, however, reduces the redundancy that could be exploited by the compression algorithm. To achieve higher compression efficiency, the authors propose using a scheme based on a turbo decoder that decides over symbols rather than bits. In the same direction and for further performance improvement, at the cost of increased encoder complexity, they also present a DSC scheme based on non-binary turbo codes. The results demonstrate improved performance. Based on the suggested algorithms, a scheme for gathering real data in wireless sensor networks and assess the corresponding energy savings is proposed.     

基于自身注意力时空特征的语音情感识别算法

针对语音情感识别中无法对关键的时空依赖关系进行建模,导致识别率低的问题,提出一种基于自身注意力（self-attention）时空特征的语音情感识别算法,利用双线性卷积神经网络、长短期记忆网络和多组注意力（multi-headattention）机制去自动学习语音信号的最佳时空表征。首先提取语音信号的对数梅尔（log-Mel）特征、一阶差分和二阶差分特征合成3D log-Mel特征集作为卷积神经网络的输入;然后综合考虑空间特征和时间依赖性关系,将双线性池化和双向长短期记忆网络的输出融合得到空间-时间特征表征,利用多组注意力机制捕获判别性强的特征;最后利用softmax函数进行分类。在IEMOCAP和EMO-DB数据库上进行实验,结果表明两种数据库的识别率分别为63.12%和87.09%,证明了此方法的有效性。     

基于双目立体视觉的物流包装箱尺寸测量研究

目的 针对物流行业运输中包装箱的非接触自动测量,提出一种基于改进SURF配准算法的双目立体尺寸测量方法。方法 首先采用二进制FREAK描述子代替传统SURF的描述子,解决传统SURF描述子计算耗时、描述向量生成依赖于特征主方向,且主方向计算误差会在后续步骤中出现传导放大 的缺点;其次,采用PROSAC删除误匹配点,并利用FREAK级联匹配的方式进一步提高算法的匹配 速度和匹配准确率。最后,利用视差优化和边缘提取算法获得精确三维空间体,实现非接触尺寸测量。结果 实验表明改进算法可快速提取图片特征点并准确匹配,对不同规格包装箱检测结果显示,基于改进算法的测量方法测量误差小,检测速度快。结论 改进图像匹配算法可有效提高图像匹配准确率,减少测量时间,对于提高物流行业运输效率、减少人工成本具有重要意义。     

Multiplexed systems for the detection of ionizing radiation

Twelve different versions of integrating encoding (multiplexed) measurement systems for recording the spatial and angular characteristics of ionizing radiation are presented. Spatial, temporal, and binary modulation of the valid signal is performed by the multiplexed measurement system, which thereby suppresses the contribution of noise to the test results and, in a number of cases, makes it possible to obtain tomographic information. Different types of periodioc (0, 1), (– 1, 1), and (– 1, 0, 1) codes and tables, methods of constructing encoders based on these codes and tables, and the basic parameters of the encoders are described.Translated from Izmeritel'naya Tekhnika, No. 11, pp. 49–54, November, 1995.     

Reliability modeling and optimization of K/N phased mission system with backup missions and global redundancy strategy

The mission success probability (MSP) is a critical indicator for phased mission systems (PMSs). In the modern aerospace industry, redundancy techniques, including component/phase redundancy, are commonly seen to increase the MSP of the whole system. These component/phase redundancies make the reliability analysis more complex. Meanwhile, one or more components are required for normal working for different subsystems, called the K/N structure. In this article, a Markov-process method is proposed for PMS with K/N subsystems and different redundancy strategies. Then, a universal system optimization model is proposed to optimize system structure and redundancy strategies for all subsystems at the same time. Then, an improved genetic algorithm (GA) is used to resolve the optimization problem. At last, a propulsion system is used as an engineering case, showing the proposed binary decision diagram-based method.     

Optical encryption system with a binary key code

A double-random-phase optical encryption system that uses a binary key code is proposed. The key code is generated as a binary computer-generated hologram. The binary key code can be displayed on a binary spatial light modulator (SLM) such as a ferroelectric liquid-crystal display. The use of a binary SLM enables us to renew the key at high speed. A joint transform correlator based on a photorefractive crystal in the Fourier domain is used to perform shift-invariant encryption and decryption. Computer simulations of the effects of using a binary encoded key code instead of a complex amplitude key code are shown. Preliminary optical experimental results are presented to demonstrate the effectiveness of the proposed system.     

QR码直接扩容技术

目的针对黑白QR码信息嵌入能力不足以及大容量信息存储的需求,提出一种QR码直接扩容技术。方法黑白QR码只有2种颜色的编码模块,每个编码模块存储1比特数据;彩色QR码拥有2n种颜色的编码模块,每个编码模块存储n比特数据,使QR码存储容量直接扩增n倍。基于HSV颜色空间模型,采用三元组配色模型进行编码模块的配色,以降低彩色编码模块间的混叠效应。采用图像对比度增强和K-Means聚类算法处理彩色编码模块的颜色偏离。结果通过对拥有16种颜色编码模块的彩色QR码数据存储性能进行分析可知,存储相同容量的数据信息,彩色QR码比黑白QR码的版本更低,QR码符号更小,实现了QR码存储容量的直接扩增。结论采用QR码直接扩容技术可实现存储容量的倍数扩增;采用K-Means聚类算法可大幅度降低彩色QR码编码模块之间的混叠效应,显著提高彩色QR码译码的正确率。     

采用液晶编码光栅的物体形貌测量新方法

提出一种基于液晶编码光栅和立体视觉技术实现物体形貌测量的新方法。该方法利用液晶显示的可控特性,按照预设编码方案,由计算机控制编码光栅的变换,产生足够的测量特征点,其突出优点在于编码变换无机械运动。根据液晶显示的特点,设计了二分值空间编码设计方案;基于立体视觉三维测量模型,提出了高精度立体视觉现场标定方法。标准平板平面度测量实验中,采用上述方法实现平面度测量精度为0.592mm。     

A new data encoding based on maximum to minimum histogram in reversible data hiding

The dual stego images based on data hiding has become popular in recent days. Since the embedding rate in dual stego images is very high. This paper proposes a new data encoding method based on maximum to the minimum histogram in reversible data hiding. This method estimates the encoded intensity from the message intensity and embeds the encoded intensity in the cover image. The stego image quality decreases the intensity of the hidden data which is high. The intensity of the data must be kept low to maintain a high-quality stego image. It is achieved using data encoding. Therefore, the proposed method uses new data encoding which converts the higher histogram data to lower intensity and the lower histogram data to higher intensity during the data embedding process. In the extraction process, the encoded intensities are decoded to message intensities to obtain the original data. The proposed data hiding approach has improved in terms of image quality (PSNR), structure similarity index measurements and embedding rate.     

Three-dimensional terahertz wave imaging

Pulsed terahertz (THz) wave sensing and imaging is a coherent measurement technology. Like radar, based on the phase and amplitude of the THz pulse at each frequency, THz waves provide temporal and spectroscopic information that allows us to develop various three-dimensional (3D) terahertz tomographic imaging modalities. The 3D THz tomographic imaging methods we investigated include THz time-of-flight tomography, THz computed tomography (CT) and THz binary lens tomography. THz time-of-flight uses the THz pulses as a probe beam to temporally mark the target, and then constructs a 3D image of the target using the THz waves scattered by the target. THz CT is based on geometrical optics and inspired from X-ray CT. THz binary lens tomography uses the frequency-dependent focal-length property of binary lenses to obtain tomographic images of an object. Three-dimensional THz imaging has potential in such applications as non-destructive inspection. The interaction between a coherent THz pulse and an object provides rich information about the object under study; therefore, 3D THz imaging can be used to inspect or characterize dielectric and semiconductor objects. For example, 3D THz imaging has been used to detect and identify the defects inside a Space Shuttle insulation tile.     

图像式一维条码识别的三重编码方法

提出一种基于三重编码的图像式一维条码快速识别算法.首先采用最大类间方差法对图像进行二值化分割,将条码从背景中分离出来.对分离出的条码图像实施倾斜校正,然后通过分析二值图像的竖直方向投影特性,建立三重编码,依次为0-1码,类行程码和条空码(条空码根据条码类型进行编码).最后由条空码进行查表和校验.识别过程能够对噪声、不齐、缺损和污染等缺陷进行有效处理.应用结果表明,该算法正确识别率达到99%以上,执行时间仅5ms左右.     

改进的基于人眼结构特征的虹膜识别方法

本文提出了一种改进的基于人眼结构特征的虹膜识别方法,基本思想是:首先,通过图像预处理,确定虹膜的位置和大小,将环形虹膜图像展开成矩形并进行归一化与图像增强;其次,利用局部灰度极小值的方法寻找有效虹膜区域内的特征点,依据纹理长度和方向信息去掉伪特征点,得到虹膜二进制编码;最后根据匹配准则进行识别.大量实验表明,该方法识别率高,识别时间短.