Research on a rodless pneumatic actuator with magnetic transfer

2021 ◽  
Vol 10 (3) ◽  
pp. 23-29
Author(s):  
Zygmunt Szczerba ◽  
Kamil Szczerba ◽  
Marta Żyłka ◽  
Wojciech Żyłka
Keyword(s):  
Pneumatic Actuator ◽  
The Real ◽  
Dynamic Operation ◽  
Numerical Tests ◽  
Magnetic Transfer

The article presents the results of experimental and numerical tests of a rodless actuator with magnetic transfer. The study concerns the dynamic operation of the actuator. A series of measurements of pressure variability as a function of the distance and speed of the actuator's operation on a real stand were performed. The study was repeated by modeling the system in the FluidSim environment. The obtained variation waveforms were compared with the real ones in order to determine the suitability of this type of tool for testing actuators.

Solving the real eigenvalues of hermitian quadratic eigenvalue problems via bisection

2015 ◽  
Vol 30 ◽  
pp. 721-743 ◽  
Author(s):  
Hao Li ◽  
Yunfeng Cai
Keyword(s):  
Eigenvalue Problems ◽  
Quadratic Eigenvalue Problem ◽  
The Real ◽  
Numerical Tests ◽  
Spring System ◽  
Quadratic Eigenvalue Problems ◽  
The Difference ◽  
Mass Spring ◽  
Quadratic Eigenvalue ◽  
Inertia Index

This paper considers solving the real eigenvalues of the Quadratic Eigenvalue Problem (QEP) Q(\lambda)x =(\lambda^2M+\lambdaC+K)x = 0 in a given interval (a, b), where the coefficient matrices M, C, K are Hermitian and M is nonsingular. First, an inertia theorem for the QEP is proven, which characterizes the difference of inertia index between Hermitian matrices Q(a) and Q(b). Several useful corollaries are then obtained, where it is shown that the number of real eigenvalues of QEP Q(\lambda)x = 0 in the interval (a, b) is no less than the absolute value of the difference of the negative inertia index between Q(a) and Q(b); furthermore, when all real eigenvalues in (a, b) are semi-simple with the same sign characteristic, the inequality becomes an equality. Based on the established theory, the bisection method (with preprocessing) can be used to compute the real eigenvalues of the QEP by computing the inertia indices. Applications to the calculation of the equienergy lines with k.p model, and also a non-overdamped mass-spring system are presented in the numerical tests.

THE EFFECTS OF BUS STOP ON TRAFFIC FLOW

2009 ◽  
Vol 20 (06) ◽  
pp. 941-952 ◽  
Author(s):  
TIE-QIAO TANG ◽  
YAN LI ◽  
HAI-JUN HUANG
Keyword(s):  
Traffic Flow ◽  
Flow Model ◽  
Initial Density ◽  
Numerical Results ◽  
Traffic Flow Model ◽  
The Real ◽  
Bus Stop ◽  
Numerical Tests ◽  
The Stability ◽  
Real Traffic

In this paper, we use the traffic flow model proposed by Tang et al. [Physica A387, 6845 (2008)] to study the effects of bus stop on traffic flow. Our numerical tests show that bus stop will have great effects on the stability of traffic flow and that the effects are related to the initial density and the number of bus stops. The numerical results are accordant with the real traffic, which shows that the model proposed by Tang et al. can describe some complex traffic phenomena resulted by bus stop.

scholarly journals Measurement Based Validation of an Electro-Pneumatic Gearbox Actuator

2019 ◽  
Vol 49 (1) ◽  
pp. 1-7 ◽  
Author(s):  
Ádám Szabó ◽  
Tamás Bécsi ◽  
Szilárd Aradi
Keyword(s):  
Dynamic Behavior ◽  
Nonlinear Model ◽  
Real System ◽  
Pneumatic Actuator ◽  
Model Parameters ◽  
The Real ◽  
Friction Parameters

The objective of the research is to analyze the behavior of the developed electro-pneumatic actuator model and compare it to the behavior of the real system. The actuator achieves the requested gear changes by moving the two pistons inside the cylinder and it is operated by three-way two-position solenoid valves. Since not all model parameters are exactly known, such as contraction coefficients and friction parameters, they can be estimated based on literature then they can be further tuned to minimize the error of the simulation. The developed nonlinear model is capable of describing the dynamic behavior of the gearbox actuator, thus it can be used to analyze the effects of constructional modifications and it can serve as Model in the Loop (MIL) environment for controller testing.

ON DIRECT METHODS FOR TIME-LIMITED SIGNAL AND IMAGE RECONSTRUCTION AND ENHANCEMENT

2007 ◽  
Vol 05 (01) ◽  
pp. 51-68
Author(s):  
YANFEI WANG ◽  
ZAIWEN WEN ◽  
ZUHAIR NASHED ◽  
QIYU SUN
Keyword(s):  
Additive Noise ◽  
Direct Methods ◽  
Computational Method ◽  
The Real ◽  
Numerical Tests ◽  
Novel Approach ◽  
Image Reconstructions ◽  
Band Limited ◽  
Value Decomposition ◽  
Fourier Matrix

The discrete Fourier transform (DFT) can be considered as an observing system, which has an input f, an output F, and a response with additive noise E. In many applications, part of the frequency spectrum/frequency information is missing or unavailable due to the passage of the time-limited signal through a band-limited system, for example, the discrete Fourier system. We suggest improving the resolution of the reconstruction of signals and images using a novel approach for the solution of the discrete Fourier system and by image enhancement. We note that the reconstruction of a time-limited signal can be simply realized by only using either the real part or the imaginary part of the DFT matrix. Therefore, based on the study of the special structure of the real and imaginary parts of the discrete Fourier matrix, a fast direct computational method is developed that utilizes explicit formulas for the truncated singular value decomposition (TSVD) obtained recently by the authors. For improving the resolution of the reconstructions, enhancement by logarithm transform is applied. This fast direct computational method is superior to other direct methods such as LU decomposition, QR decomposition, classical SVD and classical TSVD. The explicit TSVD along with the enhancement can be considered as a useful tool for signal and image reconstructions. Numerical tests for signal and image reconstructions and enhancements are given as well.

Scanning electron microscopy of human iliac bone by a simple preparation method

1990 ◽  
Vol 48 (3) ◽  
pp. 226-227
Author(s):  
Toshihiko Takita ◽  
Tomonori Naguro ◽  
Toshio Kameie ◽  
Akihiro Iino ◽  
Kichizo Yamamoto
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Preparation Method ◽  
Specimen Preparation ◽  
Real Surface ◽  
Public Attention ◽  
Preparation Methods ◽  
The Real ◽  
Simple Preparation ◽  
Scanning Electron

Recently with the increase in advanced age population, the osteoporosis becomes the object of public attention in the field of orthopedics. The surface topography of the bone by scanning electron microscopy (SEM) is one of the most useful means to study the bone metabolism, that is considered to make clear the mechanism of the osteoporosis. Until today many specimen preparation methods for SEM have been reported. They are roughly classified into two; the anorganic preparation and the simple preparation. The former is suitable for observing mineralization, but has the demerit that the real surface of the bone can not be observed and, moreover, the samples prepared by this method are extremely fragile especially in the case of osteoporosis. On the other hand, the latter has the merit that the real information of the bone surface can be obtained, though it is difficult to recognize the functional situation of the bone.

Personal Audio System: Hearing Symptoms, Habits, and Sound Pressure Levels Measured in Real Ear and a Manikin

2020 ◽  
Vol 63 (6) ◽  
pp. 2016-2026
Author(s):  
Tamara R. Almeida ◽  
Clayton H. Rocha ◽  
Camila M. Rabelo ◽  
Raquel F. Gomes ◽  
Ivone F. Neves-Lobo ◽  
...  
Keyword(s):  
Sound Pressure ◽  
Daily Basis ◽  
Cross Sectional Study ◽  
Normal Hearing ◽  
Chi Square ◽  
Cross Sectional ◽  
The Real ◽  
Significant Difference ◽  
Sound Pressure Levels ◽  
Audio System

Purpose The aims of this study were to characterize hearing symptoms, habits, and sound pressure levels (SPLs) of personal audio system (PAS) used by young adults; estimate the risk of developing hearing loss and assess whether instructions given to users led to behavioral changes; and propose recommendations for PAS users. Method A cross-sectional study was performed in 50 subjects with normal hearing. Procedures included questionnaire and measurement of PAS SPLs (real ear and manikin) through the users' own headphones and devices while they listened to four songs. After 1 year, 30 subjects answered questions about their usage habits. For the statistical analysis, one-way analysis of variance, Tukey's post hoc test, Lin and Spearman coefficients, the chi-square test, and logistic regression were used. Results Most subjects listened to music every day, usually in noisy environments. Sixty percent of the subjects reported hearing symptoms after using a PAS. Substantial variability in the equivalent music listening level (Leq) was noted ( M = 84.7 dBA; min = 65.1 dBA, max = 97.5 dBA). A significant difference was found only in the 4-kHz band when comparing the real-ear and manikin techniques. Based on the Leq, 38% of the individuals exceeded the maximum daily time allowance. Comparison of the subjects according to the maximum allowed daily exposure time revealed a higher number of hearing complaints from people with greater exposure. After 1 year, 43% of the subjects reduced their usage time, and 70% reduced the volume. A volume not exceeding 80% was recommended, and at this volume, the maximum usage time should be 160 min. Conclusions The habit of listening to music at high intensities on a daily basis seems to cause hearing symptoms, even in individuals with normal hearing. The real-ear and manikin techniques produced similar results. Providing instructions on this topic combined with measuring PAS SPLs may be an appropriate strategy for raising the awareness of people who are at risk. Supplemental Material https://doi.org/10.23641/asha.12431435

Current Issues: Evidence-Based Practice for the Real World: Thoughts on Clinical Education in Communication Disorders

2010 ◽  
Vol 20 (3) ◽  
pp. 100-105 ◽  
Author(s):  
Anne K. Bothe
Keyword(s):  
Clinical Education ◽  
Real World ◽  
Evidence Based Practice ◽  
Communication Disorders ◽  
University Faculty ◽  
Evidence Based ◽  
Speech Language Pathology ◽  
Basic Principles ◽  
The Real ◽  
Language Pathology

This article presents some streamlined and intentionally oversimplified ideas about educating future communication disorders professionals to use some of the most basic principles of evidence-based practice. Working from a popular five-step approach, modifications are suggested that may make the ideas more accessible, and therefore more useful, for university faculty, other supervisors, and future professionals in speech-language pathology, audiology, and related fields.

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