Dependence of the nonlinear behaviour stability of a ZnO nanoparticle‐Bi 2 O 3 ‐Mn 2 O 3 ‐based varistor system on cooling rates during ceramic processing

The objective of this paper is to develop a Direct Model Reference Adaptive Control (DMRAC) algorithm for a MIMO process by extending the MIT rule adopted for a SISO system. The controller thus developed is implemented on Laboratory interacting coupled tank process through simulation. This can be regarded as the relevant process control in petrol and chemical industries. These industries involve controlling the liquid level and the flow rate in the presence of nonlinearity and disturbance which justifies the use of adaptive techniques such as DMRAC control scheme. For this purpose, mathematical models are obtained for each of the input-output combinations using white box approach and the respective controllers are developed. A detailed analysis on the performance of the chosen process with these controllers is carried out. Simulation studies reveal the effectiveness of proposed controller for multivariable process that exhibits nonlinear behaviour.

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Fuzzy Sets Theory in Comparison with Stochastic Methods to Analyse Nonlinear Behaviour of a Steel Member under Compression

Nonlinear Analysis Modelling and Control ◽

10.15388/na.2005.10.1.15135 ◽

2005 ◽

Vol 10 (1) ◽

pp. 65-75 ◽

Cited By ~ 5

Author(s):

Z. Kala

Keyword(s):

Fuzzy Sets ◽

Carrying Capacity ◽

Stochastic Methods ◽

Nonlinear Behaviour ◽

Load Carrying Capacity ◽

Load Carrying ◽

Input Parameters ◽

Stochastic Solution ◽

Fuzzy Solution ◽

Sets Theory

The load-carrying capacity of the member with imperfections under axial compression is analysed in the present paper. The study is divided into two parts: (i) in the first one, the input parameters are considered to be random numbers (with distribution of probability functions obtained from experimental results and/or tolerance standard), while (ii) in the other one, the input parameters are considered to be fuzzy numbers (with membership functions). The load-carrying capacity was calculated by geometrical nonlinear solution of a beam by means of the finite element method. In the case (ii), the membership function was determined by applying the fuzzy sets, whereas in the case (i), the distribution probability function of load-carrying capacity was determined. For (i) stochastic solution, the numerical simulation Monte Carlo method was applied, whereas for (ii) fuzzy solution, the method of the so-called α cuts was applied. The design load-carrying capacity was determined according to the EC3 and EN1990 standards. The results of the fuzzy, stochastic and deterministic analyses are compared in the concluding part of the paper.

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Applying Phase Separation of a Solvent System with a Lower Critical Solution Temperature for Enhancement of Cooling Rates by Forced and Free Convection

Proceedings of the 15th International Heat Transfer Conference ◽

10.1615/ihtc15.hte.008983 ◽

2014 ◽

Cited By ~ 1

Author(s):

Amos Ullmann ◽

Itay Lipstein ◽

Neima Brauner

Keyword(s):

Phase Separation ◽

Free Convection ◽

Lower Critical Solution Temperature ◽

Solvent System ◽

Solution Temperature ◽

Cooling Rates ◽

Critical Solution Temperature

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SEISMIC CAPACITY OF MEDIUM SIZE CONTINUOUS BRIDGES WITH LEAD-RUBBER BEARINGS

NED University Journal of Research ◽

10.35453/nedjr-stmech-2019-0091 ◽

2019 ◽

Vol 3 (Special Issue on First SACEE'19) ◽

pp. 199-206

Author(s):

Bertha Olmos ◽

José Jara ◽

José Luis Fabián

Keyword(s):

Seismic Performance ◽

Seismic Vulnerability ◽

Base Isolation ◽

Elastic Behaviour ◽

Medium Size ◽

Nonlinear Behaviour ◽

Seismic Capacity ◽

Damage Scenarios ◽

Isolation Systems ◽

Rubber Bearings

This paper investigates the effects of the nonlinear behaviour of isolation pads on the seismic capacity of bridges to identify the parameters of base isolation systems that can be used to improve seismic performance of bridges. A parametric study was conducted by designing a set of bridges for three different soil types and varying the number of spans, span lengths, and pier heights. The seismic responses (acceleration, displacement and pier seismic forces) were evaluated for two structural models. The first model corresponded to the bridges supported on elastomeric bearings with linear elastic behaviour and the second model simulated a base isolated bridge that accounts for the nonlinear behaviour of the system. The seismic demand was represented with a group of twelve real accelerograms recorded on the subduction zone on the Pacific Coast of Mexico. The nonlinear responses under different damage scenarios for the bridges included in the presented study were estimated. These results allow determining the seismic capacity of the bridges with and without base isolation. Results show clearly the importance of considering the nonlinear behaviour on the seismic performance of bridges and the influence of base isolation on the seismic vulnerability of medium size bridges.

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Making Sense of Cooling Data

HortScience ◽

10.21273/hortsci.33.3.545a ◽

1998 ◽

Vol 33 (3) ◽

pp. 545a-545

Author(s):

M.D. Boyette

Keyword(s):

Fruits And Vegetables ◽

Cooling Rates ◽

Amount Of Information ◽

Making Sense ◽

Postharvest Handling ◽

Proper Analysis

Prompt cooling to remove field heat is an essential part of proper postharvest handling for many types of fresh fruits and vegetables. Growers, consultants, and horticultural agents are often encouraged to collect cooling data (time vs. temperature) in order to compare cooling rates for different systems, containers, etc. These data can be misleading and confusing and seldom yield much useful information. With proper analysis, cooling data can yield a large amount of information. The problem is not the fault of the data, as much as the lack of simple methods to analyze these data. This presentation will demonstrate several simple methods to extract useful information from cooling data.

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