A numerical study of input and output target instrumental measurement uncertainties for dimensional laser interferometry

This paper describes an extension of the SDM scheme introduced by Priestley (1980) to the problem of the identification of non-linear systems using only input/output records. It is shown that, under quite general assumptions on the structure of the system, it is possible to identify a non-linear relationship between the input and output processes via a modified version of the Kalman-type algorithm previously applied to the study of non-linear time series models. The paper includes a numerical study of data generated from various types of non-linear systems.

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Evaluation of uncertainty of measurement of shadow mask dot pitch using different approaches

Transactions of the Institute of Measurement and Control ◽

10.1177/0142331217707367 ◽

2017 ◽

Vol 40 (7) ◽

pp. 2428-2435 ◽

Cited By ~ 4

Author(s):

Girija Moona ◽

Rina Sharma ◽

Harish Kumar

Keyword(s):

Experimental Investigation ◽

Monte Carlo Simulation ◽

Laser Interferometry ◽

Shadow Mask ◽

Uncertainty Of Measurement ◽

Measurement Evaluation ◽

Alternative Approach ◽

Measurement Uncertainties ◽

Propagation Of Uncertainties ◽

Good Agreement

The present paper discusses procedure for uncertainty of measurement evaluation in an experimental investigation to measure shadow mask dot pitch using laser interferometry. Here, we discuss evaluation of uncertainty of measurement in accordance to Law of propagation of uncertainties (GUM/LPU) and Monte Carlo Simulation (MCS) approaches. MCS has been recognized as an alternative approach to LPU in guide to measurement uncertainties (GUM) for evaluation of uncertainty of measurement and other related applications. A comparison of findings of GUM/LPU and MCS is made, which appears to be in good agreement. The present study attempts to investigate the suitability of MCS for evaluation of measurement of uncertainty in case of shadow mask dot pitch and reveals the significance of MCS in this regard.

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Identification of non-linear systems using general state-dependent models

Journal of Applied Probability ◽

10.2307/3214357 ◽

1986 ◽

Vol 23 (A) ◽

pp. 257-272 ◽

Cited By ~ 1

Author(s):

M. B. Priestley ◽

S. M. Heravi

Keyword(s):

Linear Systems ◽

Linear Time ◽

Numerical Study ◽

Time Series Models ◽

General State ◽

Input And Output ◽

State Dependent ◽

Type Algorithm ◽

Non Linear ◽

Non Linear Systems

This paper describes an extension of the SDM scheme introduced by Priestley (1980) to the problem of the identification of non-linear systems using only input/output records. It is shown that, under quite general assumptions on the structure of the system, it is possible to identify a non-linear relationship between the input and output processes via a modified version of the Kalman-type algorithm previously applied to the study of non-linear time series models. The paper includes a numerical study of data generated from various types of non-linear systems.

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Air Flow Thermal and Dynamic Behavior Inside Ventilated Cavities

International Journal of Automotive and Mechanical Engineering ◽

10.15282/ijame.15.3.2018.19.0434 ◽

2018 ◽

Vol 15 (3) ◽

pp. 5652-5666

Author(s):

Y. Harnane ◽

S. Bouzid ◽

A. Brima

Keyword(s):

Thermal Field ◽

Energy Savings ◽

Numerical Study ◽

Air Flow ◽

Vertical Wall ◽

Thermal Conditions ◽

Mean Velocity ◽

Input And Output ◽

Output Behavior ◽

Ventilated Facade

This work presents a numerical study of the dynamic and thermal behavior of the air flow circulating in the vertical rectangular cavity of height H and width W. The geometry consists of a vertical wall of low thermal conductivity and an opposite wall which acts as a ventilated facade with five openings subjected to a heat flow. The methods of analyzing the flow input and output behavior through the openings throughout the ventilated facade, make the use of CFD tools "Fluent 14.0" mandatory for a detailed description. The flow is considered to be turbulent, steady, incompressible and bi-dimensional and computations are performed using the standard k-ε and RNG k-ε models for Rayleigh number ≈ 1011. The results included mean velocity profiles; flow structure and thermal field which were presented and discussed. A comparative study with conventional cavity (closed) and classical cavity with two openings (input-output) under the same thermal conditions was conducted to quantify energy savings by the use of such configuration. The increase of the number of the openings enhances the wall cooling. Moreover, above a certain heat flux absorbed by the ventilated wall, natural cooling is obsolete, it is necessary to use forced devices.

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Experimental and Numerical Study of Magnetorheological Clutch with Sealing at Larger Radius Disc

Defence Science Journal ◽

10.14429/dsj.70.15778 ◽

2020 ◽

Vol 70 (6) ◽

pp. 575-582

Author(s):

Manish Kumar Thakur ◽

Chiranjit Sarkar

Keyword(s):

Experimental Study ◽

Fluid Flow ◽

Numerical Study ◽

Outer Radius ◽

Comsol Multiphysics ◽

Optimized Design ◽

Simulation Techniques ◽

Input And Output ◽

Torque Transmission

In the existing magnetorheological clutch, there is a problem of improper transmission of torque or inefficiency in the transmission of torque. Research is carried out to improve the design of the magnetorheological clutch. Using simulation techniques and experimental study, a new seal at the outer radius is designed to improve the torque transmission of the magnetorheological clutch. The fluid flow between the input and output shafts are studied using COMSOL Multiphysics v5.3a software. The optimized design of the seal is subjected to experimental study and torque transmitted is measured. The results show an improvement in the torque transmission with the introduction of the new seal.

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