Continued fraction for formal laurent series and the lattice structure of sequences

Besides equidistribution properties and statistical independence the lattice profile, a generalized version of Marsaglia's lattice test, provides another quality measure for pseudorandom sequences over a (finite) field. It turned out that the lattice profile is closely related with the linear complexity profile. In this article we give a survey of several features of the linear complexity profile and the lattice profile, and we utilize relationships to completely describe the lattice profile of a sequence over a finite field in terms of the continued fraction expansion of its generating function. Finally we describe and construct sequences with a certain lattice profile, and introduce a further complexity measure.     

一种新型无油螺杆真空泵单头变螺距转子型线的研究

本文推出了一种适合于双螺杆式无油真空泵的单头变螺距梯形级齿凹齿面的螺杆转子型线，介绍了基本型线的生成原理和齿型的构造方法，给出了完整的型线方程和型线的一些特征参数。     

Gaussian Process Modeling and Optimization of Profile Response Experiments

Experiments where the response of interest is a curve or ‘profile’ arise in a variety of applications in engineering practice. In a recent paper (Journal of Quality Technology, 44, 2, pp. 117–135, 2012), a mixed‐effects Bayesian approach was proposed for the Bayesian optimization of profile response systems, where a particular shape of the profile response defines desired properties of the product or process. This paper proposes an alternative spatio‐temporal Gaussian random function process model for such profile response systems, which is more flexible with respect to the types of desired profile shapes that can be modeled and allows us to model profile‐to‐profile correlation, if this exists. The method is illustrated with real examples taken from the literature, and practical aspects related to model building and diagnostics are discussed. Copyright © 2013 John Wiley & Sons, Ltd.     

基于遗传算法和自适应的平面线轮廓度误差评定方法

 为了解决在测量平面线轮廓度中由于存在被测轮廓与其测量基准间存在位置误差而影响评定精度的问题，提出了一种基于遗传算法和自适应的计算平面线轮廓度误差的新方法。该方法满足最小条件原理，它利用样条插值函数拟合理论轮廓，并在评定过程中能自动地实现被测轮廓与理论轮廓之间的适应性调整，从而能够分离并消除被测轮廓与其测量基准之间的位置误差对轮廓误差评定结果的影响，在遗传优化中获得全局最优解。实例计算验证了这一结果。这种算法简单明确，具有精度高、收敛速度快、易于计算机程序实现、易于推广应用等特点。     

大型冷库螺杆压缩机几何特征及型线优化研究

目的 针对大型冷库系统用螺杆压缩机的型线设计与优化问题,建立型线几何特征计算数学模型,为螺杆压缩机型线设计与优化提供理论依据。方法 以目前广泛采用的GHH型线为研究对象,基于本文采用的型线几何特征计算方法,发现GHH型线的接触线不连续。采用圆弧-圆弧包络线共轭曲线对代替原始GHH型线中的圆弧-圆弧共轭曲线对,实现接触线的连续,提出修正的GHH型线。进而以修正的GHH型线为研究对象,分析节圆半径、齿高、双边长度等型线参数对接触线、啮合线、泄漏三角形等型线几何特征的影响。结果 研究发现,泄漏三角形的面积与节圆半径、导程呈线性正相关,与齿高、双边长度呈线性负相关,其中双边长度对泄漏三角形的面积影响最大。具体地,当节圆半径由48mm增大至60 mm时,面积利用系数由0.462减小为0.427,接触线长度由174.5 mm增大至182.2 mm,泄漏三角形面积由1.7mm²增大至8.2mm²。结论 本文建立了转子型线几何特征快速计算数学模型,对GHH型线进行了优化,实现了螺杆转子接触线的连续,揭示了型线参数对型线几何特征的影响规律,为转子型线优化提供了...     

Numerical analysis of modal dispersion in graded-index plastic optical fibers

Modal dispersion properties of a fabricated plastic optical fiber are numerically calculated through a finite-element method. The modal index, group delay, impulse response, and output pulse shape are compared with those for the power-law profile plastic optical fiber; the influence of index profile deviations from the power-law profile is described. It is shown that index profile fluctuations in the actual index profile strongly affect the group delays, even though they are relatively small. On the other hand, they have little effect on the modal indices.     

一种自调整的空间面轮廓度误差的评定方法

基于最小二乘法并结合二维样条插值函数和优化技术 ,提出一种用于空间面轮郭度误差评定的数据处理方法 ,其优点是在轮郭度误差评定过程中、能自动地实现被测轮廓与理论轮廓之间的适应性调整 ,从而能够分离并消除被测轮廓与其测量基准之间的位置误差对轮廓误差评定结果的影响。文中以汽轮机叶片轮廓的轮廓度误差评定为例 ,证实了这种评定方法的优越性。     

Precise recursive formula for calculating spot size in optical waveguides and accurate evaluation of splice loss

The spot size of a single-mode waveguide was defined from the viewpoint of a least-squares fit of the field profile to a Gaussian profile. The field profile was expanded in terms of Hermite-Gaussian functions, and a new precise recursive formula for calculating the spot size was derived. It was shown that our formula is equivalent to the best fitting of the offset coupling loss to that of a Gaussian profile and keeps its form against the Fourier transform that corresponds to the diffraction in the same manner as the Gaussian profile. The accuracy of conventional formulas and our new spot-size formula was compared with the exact value defined from the viewpoint of a least-squares fit to a Gaussian profile, and it was shown that our recursive formula is the most accurate of the approximate formulas. Next we proposed a new formula for calculating the splice loss between two waveguides and showed that our formula is more accurate than the conventional one, which involves only the spot size.     

Second-order iterative approach to inverse scattering: numerical results

We introduce an iterative algorithm for the reconstruction of dielectric profile functions from scattered field data, in which each step corresponds to the solution of a quadratic inversion problem. This means that, at each iteration, we perform a second-order approximation of the scattering operator connecting the unknown profile to the data about a reference profile function. This procedure is then compared with a linear iterative inversion algorithm, and it is pointed out that, within a prescribed class of profile functions, the linear iterative inversion does not converge to the actual solution, whereas the proposed approach does. This feature can be explained by reference not only to the improved approximation provided by the addition of a further term for profile functions of a larger norm but also to the different classes of functions that can be reconstructed by either the linear or the quadratic model. Numerical examples of profile reconstruction in the scalar two-dimensional geometry, with far-zone scattered field data at a fixed frequency, confirm the theoretical analysis.     

主轴摆动式五轴加工中扫掠轮廓线的显式计算

提出一种显式表达主轴摆动式五轴数控加工中环形刀具上扫掠轮廓线的算法.运用包络原理,推导出扫掠轮廓线的计算公式.并在此基础上,分析了轮廓线在刀具曲面不同部分的形状及几何性质,列举了轮廓线各种可能性.进而,根据线动成面的原理,构造并显示了刀具扫掠面.实例表明,所提出的计算方法高效精确,为复杂曲面五轴加工过程的动态模拟和加工误差的控制奠定了数学基础.     

A 3.2 kHz, 14-Bit Optical Absolute Rotary Encoder With a CMOS Profile Sensor

We have developed a 3.2 kHz, 14-bit optical absolute rotary encoder system using a profile sensor and a slit disc. The profile sensor, which we have designed for this purpose, is a unique CMOS area image sensor aimed at high-speed position detection of X and Y axes. Y axis profile data from the profile sensor is used for recognition of an index code on the slit disc, and X axis profile data is used for position detection of the index code. This combination of two-axis information enables high resolution even with a small number of index codes (64 indexes) and a small amount of digital calculations. Experimental results show that this system can detect rotation with an angular resolution of 14 bits (0.022deg) and a maximum detection speed of 3.2 kHz.     

Defining Shape Complexity of Extrusion Dies—A Reliabilistic View

Complexity of the profile being extruded plays a critical role in die design, die reliability, process aberrations, and product defects. Engineering common sense dictates that a more complex die should require a larger amount of extrusion force or pressure. This has been experimentally substantiated by the authors in a recent study. According to a basic definition, therefore, extrusion shape complexity is the ratio of the pressure required to extrude a complex profile to the pressure required for a solid circular profile of the same area. Most of the complexity definitions reported in published literature are based on this interrelationship between extrusion pressure and profile complexity. From a die reliability viewpoint, a complex profile is more difficult to extrude than a simple one, and it generates more stresses in the die. It should therefore lead to an earlier die failure. Another study by the authors confirms that the working life of hot extrusion dies is definitely affected by profile complexity. Reported complexity definitions provide some sort of index to measure extrudability, and can thus be used for pressure prediction to a certain degree. Unfortunately, none of these definitions addresses the very important issue of die reliability, and they generally yield a counterintuitive trend of increasing die life with increasing complexity. None of these definitions includes all the significant geometrical features of a die profile. This article reports the development of two new definitions of shape complexity (linear and power-law) incorporating all significant geometrical features of an extrusion die profile. Die failure data from a large commercial extrusion facility have been collected and analyzed. Regression-based models have been developed for prediction of die failure on the basis of complexity.     

Analysis and extraction of stepped frequency radar signature for micro-motion structure

Radar signature produced by micro-motion structures contains movement and structure information which is useful for radar target recognition. For stepped frequency (SF) radar, the Doppler modulation is coupled with the stepped carrier frequency. It shifts and smears the high-resolution range profile and makes it difficult to analyse and extract the micro-motion information from the range profile directly. The authors propose to comprehend the SF radar as a special pulse Doppler radar, and the range profile as a Doppler profile for the convenience of motion analysis. The signature of moving targets for SF radar is analysed from this point of view and the equivalent instantaneous Doppler frequency (EIDF) is introduced. Then, a typical micro-motion, rotation, is taken as an example. The sinusoidal vibration of the peaks in the range profile sequence is explained in detail, especially the relationship between the sinusoid parameters and the rotation parameters. An approach to extract the rotation parameters from the range profile or EIDF spectrum sequence is proposed based on the Hough transform. Simulated and experimental results validate the theoretical analysis and the feature extraction method.     

Three-dimensional profile curve machining on three-axis machines

Presented in this paper is a tool path generation procedure for three-dimensional profile curve machining on three-axis machines, which is essential for making dies of automotive press panels. While sculptured surface machining has received a significant amount of attention, there has been very little work on profile curve machining. The most distinctive feature of profile curve machining is that the machine operator determines the exact cutter radius at the stage of numerical control (NC) machining. For this reason, profile curve machining usually makes use of the cutter radius compensation functionality of an NC controller. In this paper, four technological requirements for the profile curve machining are identified: (1) maintaining a constant machining width; (2) avoiding controller alarms; (3) avoiding unbalanced cutter wear; and (4) retaining down-milling. To satisfy these requirements, a tool path generation procedure is proposed, implemented and tested.     

Reconstruction of a one-dimensional surface from inverse transmission

An optimization algorithm for the reconstruction of a surface profile is presented. This algorithm uses the far-field transmitted intensity to retrieve the surface profile of a thin film. We approach the inverse transmission problem as a constrained optimization problem. A mathematical representation of the surface based on B-spline curves and an optimum profile search with the self-adaptation evolutionary strategy (ES) are adopted. As the input data for the ES algorithm for surface inversion, the transmitted intensity has been measured by both a laser bidirectional reflectometer instrument and an in-line digital speckle camera system. The reconstructed 1D surfaces are compared with the profile measured by an atomic force microscope.     

Neural Dialogue Model with Retrieval Attention for Personalized Response Generation

With the success of new speech-based human-computer interfaces, there is a great need for effective and friendly dialogue agents that can communicate with people naturally and continuously. However, the lack of personality and consistency is one of critical problems in neural dialogue systems. In this paper, we aim to generate consistent response with fixed profile and background information for building a realistic dialogue system. Based on the encoder-decoder model, we propose a retrieval mechanism to deliver natural and fluent response with proper information from a profile database. Moreover, in order to improve the efficiency of training the dataset related to profile information, we adopt a method of pre-training and adjustment for general dataset and profile dataset. Our model is trained by social dialogue data from Weibo. According to both automatic and human evaluation metrics, the proposed model significantly outperforms standard encoder-decoder model and other improved models on providing the correct profile and high-quality responses.     

Monitoring nonlinear profile data using support vector regression method

In today's manufacturing industries, if the quality characteristic of a product or a process is assumed to be represented by a functional relationship between the response variable and one or more explanatory variables, then the data generated from such a relationship are called profile data. Generally speaking, the functional relationship of the profile data rarely occurs in linear form, and the real data usually do not follow normal distribution. Thus, in this paper, the functional relationship of profile data is described via a nonparametric regression model and a nonparametric exponentially weighted moving average (EWMA) control chart is developed for detecting the process shifts for nonlinear profile data in the Phase II monitoring. We first fit the nonlinear profile data via a support vector regression model and use the fitted values to calculate the five metrics. Then, the nonparametric EWMA control chart with the five metrics can be constructed accordingly. Moreover, a simulation study is conducted to evaluate the detecting performance of the new control chart under various process shifts using the out‐of‐control average run length. Finally, a realistic nonlinear profile example is used to demonstrate the usefulness of our proposed nonparametric EWMA control chart and its monitoring schemes. It is expected that the proposed nonparametric EWMA control chart can enhance the monitoring efficiency for nonlinear profile data in the phase II study.     

基于接触应力优化的摆线轮修形设计

对摆线轮进行合理的修形能够极大改善RV（rotary vector,旋转矢量）减速器的传动性能和承载能力。为了进一步优化“反弓”齿廓的接触应力,在综合分析组合修形对反弓齿廓啮合力和接触应力的影响的基础上,提出了一种两段修形方法。该方法是将摆线轮齿廓分成2段,并根据需要对不同工作段的齿廓采用不同的修形量,以更灵活地设计摆线轮的齿廓。以RV-40E减速器为例,先利用MATLAB软件建立摆线轮受力分析模型,并按照两段修形方法确定新齿廓的修形量和方程;再利用ANSYS软件建立摆线轮与针齿接触的有限元模型,并对比新齿廓与反弓齿廓的接触应力。理论计算结果显示,新齿廓的最大接触应力降低了8.34%;有限元仿真结果显示,新齿廓的最大接触应力降低了4.39%,并分析了可能的误差来源。研究表明,两段修形方法可以改善摆线轮齿廓的接触应力和延长摆线轮的使用寿命,这为摆线轮的修形设计提供了一定的参考。     

Does the performance of wet granulation and tablet hardness affect the drug dissolution profile of carvedilol in matrix tablets?

Wet granulation is mostly used process for manufacturing matrix tablets. Compared to the direct compression method, it allows for a better flow and compressibility properties of compression mixtures. Granulation, including process parameters and tableting, can influence critical quality attributes (CQAs) of hydrophilic matrix tablets. One of the most important CQAs is the drug release profile. We studied the influence of granulation process parameters (type of nozzle and water quantity used as granulation liquid) and tablet hardness on the drug release profile. Matrix tablets contained HPMC K4M hydrophilic matrix former and carvedilol as a model drug. The influence of selected HPMC characteristics on the drug release profile was also evaluated using two additional HPMC batches. For statistical evaluation, partial least square (PLS) models were generated for each time point of the drug release profile using the same number of latent factors. In this way, it was possible to evaluate how the importance of factors influencing drug dissolution changes in dependence on time throughout the drug release profile. The results of statistical evaluation show that the granulation process parameters (granulation liquid quantity and type of nozzle) and tablet hardness significantly influence the release profile. On the other hand, the influence of HPMC characteristics is negligible in comparison to the other factors studied. Using a higher granulation liquid quantity and the standard nozzle type results in larger granules with a higher density and lower porosity, which leads to a slower drug release profile. Lower tablet hardness also slows down the release profile.     

On the Monitoring of Simple Linear Berkson Profiles

We consider the quality of a process, which can be characterized by a simple linear Berkson profile. One existing approach for monitoring the simple linear profile and two new proposed schemes are studied for charting the simple linear Berkson profile. Simulation studies demonstrate the effectiveness and efficiency of one of the proposed monitoring schemes. In addition, a systematic diagnostic approach is provided to spot the change point location of the process and to identify the parameter of change in the profile. Finally, an example from semiconductor manufacturing is used to illustrate the implementation of the proposed monitoring scheme and diagnostic approach. Copyright © 2012 John Wiley & Sons, Ltd.