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IEEE International Conference on Industrial Engineering and Engineering Management (IEEM 2009)

作者： Xie, C. Zhang, W. M. He, X. Y. Tongji Univ Coll Mech Engn Shanghai 200092 Peoples R China Sheyang Machine Tool Grp Co LTD Design & Res Inst Shenyang Peoples R China

ISBN: (纸本)9781424448692

Improving the accuracy of 5-axis CNC machine tools is a problem for professional people to solve all the time. Its kinematic configuration and numerical control algorithm are crucial factors affecting errors. All the possible structural configurations of 5-axis CNC machine tools with a universal head were shown in this study. The optimal kinematic chain was presented from the view of kinematic errors and workpiece degrees of freedom (DOF). The general calculating formulation of tool center point (TCP) deduced by analyzed the special movement of 5-axis CNC machine tools with a universal head. It is pointed out that the tool axis orientation (TAO) only depends on rotational movements instead of translational ones. The post-processing algorithm of CAM programs was solved out through compound transmission matrix. It was concluded that TCP coordinate value, tool axis orientation and post-processing algorithm can not be changed with the sequence change of movement axes for 5-axis CNC machine tools with a universal head

关键词： Kinematic analysis post-processing algorithm 5-axis CNC machine tools with a universal head Kinematic errors

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Ultrasonic Nondestructive Evaluation of Composite Components using Advanced Total Focusing Method

Ultrasonic Nondestructive Evaluation of Composite Components...

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3rd International Conference on Advances in Materials Manufacturing (ICAMMP 2012)

作者： Xu, Na Li, Yang Zhou, Zhenggan Beihang Univ Sch Mech Engn & Automat Beijing 100191 Peoples R China

ISBN: (纸本)9783037856208

The application of ultrasonic phased array has been increasingly common in nondestructive testing and evaluation of composite components. An advanced post-processing imaging algorithm of ultrasonic array, termed total focusing method, is introduced to improve imaging quality and detection ability. Then, the experiment system is developed to capture and store the time domain signals from every transmitter-receiver pair. This imaging algorithm is implemented to detect standard phased array sample and shown to offer increased sensitivity to small defects and greater inspection coverage. Finally, experiments are carried out for composite components. The results show this approach has significant performance advantages for nondestructive testing of composite components.

关键词： Nondestructive evaluation Composites Ultrasonic phased array post-processing algorithm

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post-filtering algorithm for cross-talk cancellation in blind source separation outputs

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IET SIGNAL processing 2012年第3期6卷 239-246页

作者： Noohi, T. Kahaei, M. H. Iran Univ Sci & Technol Sch Elect Engn Tehran Iran

In this study, cross-talk cancellation in convolutive blind source separation (BSS) is investigated using a new post-processing algorithm. In this algorithm, exclusive activity periods (EAPs) are used to model cross-talks in which only one BSS output signal is assumed to be active. Inactive intervals of each EAP are used to estimate the cross-talk leaked from each active signal. Then, the estimated cross-talk is subtracted from BSS outputs. Simulation results show that the proposed algorithm successfully suppresses the crosstalk by improving the signal-to-interference ratio (SIR) and signal-to-distortion ratio (SDR) of BSS outputs about 12 and 5 dB, respectively.

关键词： post-processing algorithm Electromagnetic compatibility and interference signal-to-interference ratio signal-to-distortion ratio cross-talk cancellation Digital signal processing SIR exclusive activity periods SDR post-filtering algorithm crosstalk filtering theory Signal processing theory blind source separation Signal processing and detection interference suppression

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An effective algorithm for computing global sensitivity indices (EASI)

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RELIABILITY ENGINEERING & SYSTEM SAFETY 2010年第4期95卷 354-360页

作者： Plischke, Elmar Tech Univ Clausthal Inst Endlagerforsch D-38678 Clausthal Zellerfeld Germany

We present an algorithm named EASI that estimates first order sensitivity indices from given data using Fast Fourier Transformations. Hence it can be used as a post-processing module for pre-computed model evaluations. Ideas for the estimation of higher order sensitivity indices are also discussed. (C) 2009 Elsevier Ltd. All rights reserved.

关键词： Global sensitivity analysis Sobol' sensitivity indices FAST method Correlation ratio post-processing algorithm Space filling curves

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Specific Absorption rate (SAR) post-processing Implementation: Numerical Approach

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IEEE ANTENNAS AND PROPAGATION MAGAZINE 2010年第5期52卷 180-184页

作者： Akram, Gasmelseed UTM Fac Elect Engn Skudai 81310 Johor Bahru Malaysia

The accepted dosimetric measure of electromagnetic (EM) exposure is the specific absorption rate (SAR), which is defined as the power absorbed per unit mass of tissue. International standards for compliance testing of hand-held mobile communication devices define various cubical averaging schemes to obtain the spatial peak averaged specific absorption rate. In this paper, a numerical approach to illustrate the validation and uncertainty contributions of a SAR post-processing algorithm is described. Simplified interpolation and extrapolation techniques to calculate the 19 SAR for a 2.5 mm mesh grid are evaluated. Furthermore, using linear, nearest, and spline interpolation in MATLAB, the effects of the extrapolation order on the assessment of the resultant error are examined.

关键词： Dosimetry extrapolation interpolation post-processing algorithm spatial peak averaged SAR biological effects of electromagnetic radiation

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Pitfalls and advantages of different strategies for the absolute quantification of N-acetyl aspartate, creatine and grey matter by ¹H-MRS

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NMR IN BIOMEDICINE 2009年第10期22卷 1003-1013页

作者： Malucelli, E. Manners, D. N. Testa, C. Tonon, C. Lodi, R. Barbiroli, B. Iotti, S. Univ Bologna Dipartimento Med Interna Invecchiamento & Malatti I-40138 Bologna Italy Ist Nazl Biostrutture & Biosistemi Rome Italy

This study extensively investigates different strategies for the absolute quantitation of N-acetyl aspartate, creatine and choline in white and grey matter by H-1-MRS at 1.5 T. The main focus of this study was to reliably estimate metabolite concentrations while reducing the scan time, which remains as one of the main problems in clinical MRS. Absolute quantitation was based on the water-unsuppressed concentration as the internal standard. We compared strategies based on various experimental protocols and post-processing strategies. Data were obtained from 30 control subjects using a PRESS sequence at several TE to estimate the transverse relaxation time, T-2, of the metabolites. Quantitation was performed with the algorithm QUEST using two different metabolite signal basis sets: a whole-metabolite basis set (WhoM) and a basis set in which the singlet signals were split from the coupled signals (MSM). The basis sets were simulated in vivo for each TE used. Metabolites' T(2)s were then determined by fitting the estimated signal amplitudes of the metabolites obtained at different TEs. Then the absolute concentrations (mM) of the metabolites were assessed for each subject using the estimated signal amplitudes and either the mean estimated relaxation times of all subjects (mean protocol, MP) or the T-2 estimated from the spectra derived from the same subject (individual protocol, IP). Results showed that MP represents a less time-consuming alternative to IP in the quantitation of brain metabolites by H-1-MRS in both grey and white matter, with a comparable accuracy when performed by MSM. It was also shown that the acquisition time might be further reduced by using a variant of MP, although with reduced accuracy. In this variant, only one water-s up pressed and one water-unsuppressed spectra were acquired, drastically reducing the duration of the entire MRS examination. However, statistical analysis highlights the reduced accuracy of MP when performed using WhoM, particu

关键词： absolute quantification brain metabolites H-1-MRS post-processing algorithm spectral analysis

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A post-processing approach to improve emotion recognition rates

A post-processing approach to improve emotion recognition ra...

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8th International Conference on Signal processing

作者： Pittermann, Johannes Pittermann, Angela Univ Ulm Dept Informat Technol D-89069 Ulm Germany

ISBN: (纸本)9780780397361

The involvement of emotions in intelligent human-machine interfaces has evolved to a recent field of research. This does not only include the handling of emotions in dialogue management but also the classification of emotions. In this paper we focus on emotion recognition from speech signals and moreover on how to improve recognition results using a post-processing approach. At first we give a short overview on emotion recognition and on corpus which we modified and used in our experiments. Then we describe Fiscus' ROVER system and the way of how to adapt it to emotion recognition. Finally we present zipper and lower bounds for the system's recognition performance in selected experiments.

关键词： speech processing and recognition emotion recognition post-processing algorithm

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A post-processing Approach to Improve Emotion Recognition Rates

A Post-Processing Approach to Improve Emotion Recognition Ra...

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2006 8th International Conference on Signal processing

作者： Johannes Pittermann Angela Pittermann Dept.of Information Technology University of Ulm89069 UlmGermany

The involvement of emotions in intelligent humanmachine interfaces has evolved to a recent field of research. This does not only include the handling of emotions in dialogue management but also the classification of *** this paper we focus on emotion recognition from speech signals and moreover on how to improve recognition results using a post-processing *** first we give a short overview on emotion recognition and on corpus which we modified and used in our *** we describe Fiscus' ROVER system and the way of how to adapt it to emotion recognition. Finally we present upper and lower bounds for the system's recognition performance in selected experiments.

关键词： Speech processing and recognition Emotion recognition post-processing algorithm

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Estimation of the liquid velocity field in two-phase flows using inverse analysis and particle tracking velocimetry

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FLOW MEASUREMENT AND INSTRUMENTATION 2005年第5期16卷 303-308页

作者： Cheng, W Murai, Y Yamamoto, F Xian Univ Technol Environm Res Inst Xian 710048 Shaanxi Peoples R China Hokkaido Univ Grad Sch Engn Div Mech Sci Kita Ku Sapporo Hokkaido 0608628 Japan Univ Fukui Grad Sch Engn Fiber Amen Engn Course Fukui 9108507 Japan

In bubbly two-phase flow, the gas phase and liquid phase have different flow fields. The relative velocity of the two phases depends on the motion characteristic of the bubbles. The mathematical expression for the motion of a small bubble at low Reynolds number is already established. Using the equation, the liquid velocity along the trajectory of the bubble is calculated inversely using the motion equation. Whole field liquid flow structure is also estimated using a spatial and/or temporal interpolation method. This paper proposes an algorithm for estimating the liquid phase flow field from measurement data on bubble motion. In order to verify this principle, Taylor-Green vortex flow and Karman vortex shedding from a square cylinder have been chosen. The results reveal that by combining the inverse analysis and PTV with the spatio-temporal post-processing algorithm one can reconstruct well the carrier phase flow of the gas-liquid two-phase flow. (c) 2005 Published by Elsevier Ltd

关键词： particle tracking velocimetry multiphase flow inverse analysis post-processing algorithm carrier phase dispersed phases

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LIQUID PHASE FLOW ESTIMATION IN GAS-LIQUID TWO-PHASE FLOW USING INVERSE ANALYSIS AND PARTICLE TRACKING VELOCIMETRY

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Journal of Hydrodynamics 2004年第6期16卷 730-736页

作者： CHENGWen MURAlYuichi SASAKIToshio YAMAMOTOFujio DepartmentofMechanicalEngineering UniversityofFukuiFukuiJapan DivisionofMechanicalScience HokkaidoUniversityHokkaidoJapan DepartmentofMechanicalEngineering UniversityofFukuiFukuiJapan／／EnvironmentResearchInstituteXianUniversityofTechnologyXi＇an710048China

An inverse analysis algorithm is proposed for estimating liquid phase flowfield from measurement data of bubble motion. This kind of technology will be applied in future forvarious estimation of fluid flow in rivers, lakes, sea surface flow, and also microscopic channelflow as the problem-handling in civil, mechanical, electronic, and chemical engineering. Therelationship between the dispersion motion and the carrier phase flow is governed and expressed bythe trans-lational motion equation of spherical dispersion. The equation consists of all the forcecomponents including inertia, added inertia, drag, lift, pressure gradient force and gravity *** this equation enables us to estimate the carrier phase flow structure using only the data ofthe dispersion motioa Whole field liquid flow structure is also estimated using spatial or temporalinterpolation method. In order to verify this principle, the Taylor-Green vortex flow, and theKarman vortex shedding from a square cylinder have been chosea The results show that the combinationof the inverse analysis and Particle Tracking Velocimetry (PTV) with the spatio-temporalpostprocessing algorithm could reconstruct well the carrier phase flow of the gas-liquid two-phaseflow.

关键词： particle tracking velocimetry(PTV) multiphase flow inverse analysis post-processing algorithm carrier phase dispersed phases

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