Signal-to-noise-ratio analysis for nonlinear N-ary phase filters

The problem of recognizing targets in nonoverlapping clutter using nonlinear N-ary phase filters is addressed. Using mathematical analysis, expressions were derived for an N-ary phase filter and the intensity variance of an optical correlator output. The N-ary phase filter was shown to consist of an infinite sum of harmonic terms whose periodicity was determined by N. For the intensity variance, it was found that under certain conditions the variance was minimized due to a previously undiscovered phase quadrature effect. Comparison showed that optimal real filters produced greater signal-to-noise-ratio values than the continuous phase versions as a consequence of this effect.     

Efficient texture analysis for industrial inspection

This paper describes a convolution-based approach to the analysis of images containing few texture classes. Segmentation of foreground and background textures, or detection of boundaries between similarly textured objects, is demonstrated. The application to industrial inspection applications is demonstrated. Near frame-rate performance on low-cost hardware is possible, since only convolution with small kernels is used. A new algorithm to optimize convolution kernels for the required texture analysis task is presented. A key feature of the paper is the industrial readiness of the techniques described.     

Comparative analysis on some filters for wrapped phase maps

Some effective filtering methods for wrapped phase maps, a regularized phase-tracking method (RPT) without the regularization term, a multiple-parameter least-square method (MPLS), a windowed Fourier ridges method (WFR), an autocorrelation function method (ACF), and a sine/cosine average filter (SCAF), are analyzed in order to establish their transversal relationship. The analysis shows that principles of the RPT, MPLS, WFR, and ACF are equivalent and the SCAF also leads to the WFR by some extension, which elegantly unifies all these methods for filtering unwrapped phase maps.     

Efficient tool path planning for five-axis surface machining with a drum-taper cutter

This paper presents a new efficient approach to NC tool path generation for five-axis surface machining. First, an efficient cutter, named a drum-taper cutter, is proposed; its key dimension is determined to avoid gouging in surface machining according to the maximum curvature of the surface calculated with a genetic algorithm. Then, based on the drum-taper cutter, the tool paths are generated so that the scallop height formed by adjacent tool paths in machining is kept constant, and an improved algorithm for calculating the interval between tool paths is presented. Finally, an example of tool path generation with the above method for arbitrary surface impeller machining is conducted, and the results show that the presented method leads to a significant reduction in the total tool path length and is accompanied by a reduction in machining time.     

Comparative analysis on some spatial-domain filters for fringe pattern denoising

Fringe patterns produced by various optical interferometric techniques encode information such as shape, deformation, and refractive index. Noise affects further processing of the fringe patterns. Denoising is often needed before fringe pattern demodulation. Filtering along the fringe orientation is an effective option. Such filters include coherence enhancing diffusion, spin filtering with curve windows, second-order oriented partial-differential equations, and the regularized quadratic cost function for oriented fringe pattern filtering. These filters are analyzed to establish the relationships among them. Theoretical analysis shows that the four filters are largely equivalent to each other. Quantitative results are given on simulated fringe patterns to validate the theoretical analysis and to compare the performance of these filters.     

基于MLS-SVM的结构整体可靠度与全局灵敏度分析

全局灵敏度分析,旨在考量结构系统中各输入随机变量对输出响应不确定性及风险水平影响的重要度。它能为后续的可靠度评估、故障诊断、系统设计、预测及优化等提供重要参考。尽管各类全局灵敏度分析方法不断涌现,但高维复杂结构(如风机叶片结构)灵敏度分析仍是目前的难题。该文针对空间分割全局灵敏度分析方法的三种可能计算形式及最优分割方案展开研究,通过标准算例分析和误差理论推导,提出能充分利用样本信息、有效减轻计算负担的求解形式及分割方案,并将其应用于风机叶片极限载荷工况下的全局灵敏度分析中,同时为未来设计更为高效、经济和可靠的风机结构提供参考。

     

Efficient explicit formulation for practical fuzzy structural analysis

This paper presents a practical approach based on High Dimensional Model Representation (HDMR) for analysing the response of structures with fuzzy parameters. The proposed methodology involves integrated finite element modelling, HDMR based response surface generation, and explicit fuzzy analysis procedures. The uncertainties in the material, geometric, loading and structural parameters are represented using fuzzy sets. To facilitate efficient computation, a HDMR based response surface generation is employed for the approximation of the fuzzy finite element response quantity.     

FEPACS: A computational tool for linear structural analysis

FEPACS (Finite Element Package for linear static, dynamic and instability Analysis of Composite Structures under hygro-thermo-mechanical loads) incorporates a complete library of consistent and correct 1-, 2- and 3-dimensional linear and quadratic general purpose finite elements. In this paper, we shall discuss the finite element technology that has gone into the package as well as its present modelling and solution capabilities. We shall also discuss briefly recent developments toward enhancing the package: Robust composite elements based on aC ⁰-continuous higher order transverse deformation plate/beam theory, and nonlinear element technology and solution strategies. Finally, we shall also briefly touch upon several satellite application modules that are in different stages of planning/development to aid FEPACS: damage assessment/prediction,expert-like advisors for solid modelling and finite element modelling/analysis, pre-/post-processing for FEPACS applications, structural optimisation and related finite element algorithms, and finally, a frontal solution module for FEPACS to enhance its feasibility for vectorisation/parallelisation.     

Idealized analysis of SAW longitudinally coupled resonator filters

A surface acoustic wave (SAW) longitudinally coupled resonator (LCR) filter consists of either two or three interdigital transducers located between two strongly reflecting gratings. The behavior of this structure is, in general, very complex because the transducers are of the single-electrode type, which gives strong electrode reflections. It is shown here that, for the filter passband, a number of realistic assumptions can be used to derive a very simple set of approximate relations for the device Y-matrix. The simplifications involve reciprocity, symmetry, and power conservation. The theory also uses the necessary fact that each grating, combined with its adjacent transducer, must have high directivity so that application of a voltage results in wave generation primarily toward the center of the device. For a three-transducer device, it is shown using symmetry that the central transducer behaves as if it were transparent, despite having strong electrode reflections. Hence, the device behaves as a single resonant cavity. The simple Y-matrix formulae are shown to agree very well with accurate results obtained by a coupling-of-modes (COM) analysis for both types of device. They also lead to simple formulae for the electrical loading required to obtain a flat, low-loss filter response. Equivalent circuits also are discussed.     

Digital filters in human ECG processing and analysis

Algorithms are described for filters in the Kardiosistema-3 package written at the Laser Medical Technology organization in Moscow for use with an IBM PC AT personal computer.Translated from Izmeritel'naya Tekhnika, No. 2, pp. 59–61, February, 1994.     

Nonnegative color spectrum analysis filters from principal component analysis characteristic spectra

Nonnegative color analysis filters are obtained by using an invertible linear transformation of characteristic spectra, which are orthogonal vectors from a principal component analysis (PCA) of a representative ensemble of color spectra. These filters maintain the optimal compression properties of the PCA scheme. Linearly constrained nonlinear programming is used to find a transformation that minimizes the noise sensitivity of the filter set. The method is illustrated by computing analysis and synthesis filters for an ensemble of measured Munsell color spectra.     

Patent citation analysis: A policy analysis tool

Patent citation analysis is a recent development which uses bibliometric techniques to analyse the wealth of patent citation information. This paper describes the various facets of patent citations and patent citation studies, and their important applications. Construction of technology indicators being an important use of patent citations, various patent citation based technological indicators and their applications are also described.     

An interactive tool for the analysis of nuclear emulsion data

In this paper, we present an interactive tool developed to analyze and display events recorded in nuclear emulsion experiments. Besides providing an excellent way to complement automatic emulsion scanning techniques this program implements a new approach for the complete three-dimensional (3D) analysis of the events.The program uses information recorded during automatic emulsion scanning procedure and commonly called “video images.” The main features implemented are: automatic full track reconstruction up to wide angles (∼0.8 rad) with efficiency greater than 95%, vertex finding, “kink”’ finding, two-dimensional “microscope” visualization, 3D full view display and analysis.Performances were evaluated using a large set of video images containing manually checked neutrino interaction events and preliminary test beam exposure data.     

Acoustic emission analysis for tool wear monitoring in face milling

Monitoring the condition of the cutting tool in any machining operation is very important since it will affect the workpiece quality and an unexpected tool failure may damage the tool, workpiece and sometimes the machine tool itself. Advanced manufacturing demands an optimal machining process. Many problems that affect optimization are related to the diminished machine performance caused by worn out tools. One of the most promising tool monitoring techniques is based on the analysis of Acoustic Emission (AE) signals. The generation of the AE signals directly in the cutting zone makes them very sensitive to changes in the cutting process. Various approaches have been taken to monitor progressive tool wear, tool breakage, failure and chip segmentation while supervising these AE signals. In this paper, AE analysis is applied for tool wear monitoring in face milling operations. Experiments have been conducted on En-8 steel using uncoated carbide inserts in the cutter. The studies have been carried out with one, two and three inserts in the cutter under given cutting conditions. The AE signal analysis was carried out by considering signal parameters such as ring down count and RMS voltage. The results show that AE can be effectively used to monitor tool wear in face milling operation.     

A rapid tool for strategic internal analysis of manufacturing firms

This paper examines strengths and weaknesses of companies in the context of the value chain as a way to assess a manufacturing firm. For doing this, the executives of 20 companies were interviewed and asked about the strengths and weaknesses they thought their companies had. The responses were classified according to the elements of the value chain and new sub-classifications were created. In this way, it was possible to discover the main concerns the executives had about their company and to see if there were some comonality in their responses. It was found that the main concerns were in the areas of Production and Sales, as opposed to Finances, Human Resources, Technology and Procurement. As a result, a proposition is made about the use of this value chain and its dimensions as a way for rapid internal assessment of a manufacturing firm. A case study is presented in which the developed tool was implemented. An internal analysis of a company was undertaken in few hours.     

Monoclonal antibody cocktail as an enrichment tool for acetylome analysis

The availability and robustness of methods to analyze phosphorylated proteins has greatly expanded our knowledge of phosphorylation based cell signaling. A key ingredient to the success of these studies is the ability to enrich phosphopeptides using antibodies or other chemical approaches. Most other post-translational modifications, such as lysine acetylation, are still poorly characterized because of the lack of availability of such enrichment methods. Recently, some groups have reported identification of acetylation sites in a global fashion by enriching acetylated peptides with a polyclonal antibody from a single source that was raised against pan-acetylated lysine. Instead of the use of this polyclonal antibody, we used a cocktail of monoclonal antibodies where each was directed against acetylated lysine in different contexts. Using high resolution Fourier transform mass spectrometry, we observed that the majority of acetylated lysine residues identified using the monoclonal antibody cocktail were distinct from those enriched by the polyclonal antibody used by the other groups. Our study demonstrates that immunoaffinity enrichment of acetylated peptides is somewhat limited by substrate specificity and that an optimal yield of enrichment can be achieved by employing a broader array of affinity reagents.