A Measurement System for Power Inductors in Non-Linear Operating Conditions

Remote farms in Africa are cultivated lands planned for 100% sustainable energy and organic agriculture in the future. This paper presents the load frequency control of a two-area power system feeding those farms. The power system is supplied by renewable technologies and storage facilities only which are photovoltaics, biogas, biodiesel, solar thermal, battery storage and flywheel storage systems. Each of those facilities has 150-kW capacity. This paper presents a model for each renewable energy technology and energy storage facility. The frequency is controlled by using a novel non-linear fractional order proportional integral derivative control scheme (NFOPID). The novel scheme is compared to a non-linear PID controller (NPID), fractional order PID controller (FOPID), and conventional PID. The effect of the different degradation factors related to the communication infrastructure, such as the time delay and packet loss, are modeled and simulated to assess the controlled system performance. A new cost function is presented in this research. The four controllers are tuned by novel poor and rich optimization (PRO) algorithm at different operating conditions. PRO controller design is compared to other state of the art techniques in this paper. The results show that the PRO design for a novel NFOPID controller has a promising future in load frequency control considering communication delays and packet loss. The simulation and optimization are applied on MATLAB/SIMULINK 2017a environment.

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Remote Heat Pipe Based Heat Exchanger Performance in Notebook Cooling

Heat Transfer: Volume 4 ◽

10.1115/ht2005-72069 ◽

2005 ◽

Cited By ~ 1

Author(s):

Seyyed Khandani ◽

Himanshu Pokharna ◽

Sridhar Machiroutu ◽

Eric DiStefano

Keyword(s):

Heat Exchanger ◽

Thermal Resistance ◽

Heat Pipe ◽

Cooling System ◽

Temperature Drop ◽

Operating Conditions ◽

Cooling Systems ◽

Temperature Variations ◽

Non Linear ◽

Condenser Temperature

Remote heat pipe based heat exchanger cooling systems are becoming increasingly popular in cooling of notebook computers. In such cooling systems, one or more heat pipes transfer the heat from the more populated area to a location with sufficient space allowing the use of a heat exchanger for removal of the heat from the system. In analsysis of such systems, the temperature drop in the condenser section of the heat pipe is assumed negligible due to the nature of the condensation process. However, in testing of various systems, non linear longitudinal temperature drops in the heat pipe in the range of 2 to 15 °C, for different processor power and heat exchanger airflow, have been measured. Such temperature drops could cause higher condenser thermal resistance and result in lower overall heat exchanger performance. In fact the application of the conventional method of estimating the thermal performance, which does not consider such a nonlinear temperature variations, results in inaccurate design of the cooling system and requires unnecessarily higher safety factors to compensate for this inaccuracy. To address the problem, this paper offers a new analytical approach for modeling the heat pipe based heat exchanger performance under various operating conditions. The method can be used with any arbitrary condenser temperature variations. The results of the model show significant increase in heat exchanger thermal resistance when considering a non linear condenser temperature drop. The experimental data also verifies the result of the model with sufficient accuracy and therefore validates the application of this model in estimating the performance of these systems. This paper was also originally published as part of the Proceedings of the ASME 2005 Pacific Rim Technical Conference and Exhibition on Integration and Packaging of MEMS, NEMS, and Electronic Systems.

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Position Control of Hydraulic Actuators Using Fuzzy Pulse Width Modulation (PWM)

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.735.294 ◽

2015 ◽

Vol 735 ◽

pp. 294-298 ◽

Cited By ~ 1

Author(s):

Wei Ying Lai ◽

Nurfarahin Onn ◽

Collin Howe Hing Tang ◽

Mohamed Hussein

Keyword(s):

Fuzzy Logic ◽

Pulse Width ◽

Pulse Width Modulation ◽

Solenoid Valve ◽

Operating Conditions ◽

Hydraulic Actuators ◽

Non Linear ◽

Fuzzy Logic Approach ◽

Logic Approach ◽

Non Linear System

Hydraulic actuators are widely employed for industrial automation for its high power over weight ratio, functionality in tough operating conditions and low cost. However, the dynamics of hydraulic systems are non-linear and the system subjected to non-smooth and discontinuous non-linearities due to directional change of valve opening, friction, valve overlap and changes of hydraulic pressure acted on valve spool. Taking into account the effect of nonlinear parameter variations such as bulk modulus, compressibility of oil or viscosity of oil, fuzzy logic approach is chosen. Fuzzy control can adapt the inconstant working condition and non-linear system alongside of its robustness. For PWM controlled hydraulic component such as solenoid valve, effective approximation of the flow properties in a solenoid valve is essential. In this paper, the effect of fuzzy logic approach incorporated on pulse width modulation (PWM) controlled hydraulic system is to be investigated and experimentally verified.

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Belousov-Zhabotinsky type reactions: the non-linear behavior of chemical systems

Journal of Mathematical Chemistry ◽

10.1007/s10910-021-01223-9 ◽

2021 ◽

Author(s):

Andrea Cassani ◽

Alessandro Monteverde ◽

Marco Piumetti

Keyword(s):

Open Systems ◽

Deterministic Chaos ◽

General Information ◽

Operating Conditions ◽

Chemical Oscillators ◽

Chemical Systems ◽

Linear Behavior ◽

Oscillatory Reactions ◽

Non Linear ◽

Belousov Zhabotinsky Reaction

AbstractChemical oscillators are open systems characterized by periodic variations of some reaction species concentration due to complex physico-chemical phenomena that may cause bistability, rise of limit cycle attractors, birth of spiral waves and Turing patterns and finally deterministic chaos. Specifically, the Belousov-Zhabotinsky reaction is a noteworthy example of non-linear behavior of chemical systems occurring in homogenous media. This reaction can take place in several variants and may offer an overview on chemical oscillators, owing to its simplicity of mathematical handling and several more complex deriving phenomena. This work provides an overview of Belousov-Zhabotinsky-type reactions, focusing on modeling under different operating conditions, from the most simple to the most widely applicable models presented during the years. In particular, the stability of simplified models as a function of bifurcation parameters is studied as causes of several complex behaviors. Rise of waves and fronts is mathematically explained as well as birth and evolution issues of the chaotic ODEs system describing the Györgyi-Field model of the Belousov-Zhabotinsky reaction. This review provides not only the general information about oscillatory reactions, but also provides the mathematical solutions in order to be used in future biochemical reactions and reactor designs.

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Studies on AM and PM noise in microwave amplifiers working under linear and non-linear operating conditions

2015 Asia-Pacific Microwave Conference (APMC) ◽

10.1109/apmc.2015.7411741 ◽

2015 ◽

Author(s):

J. Portilla ◽

R. Jauregui

Keyword(s):

Operating Conditions ◽

Microwave Amplifiers ◽

Non Linear

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Non-linear dynamics of the Villari effect in the presence of a non-homogeneous magnetic field

Proceedings of the Institution of Mechanical Engineers Part I Journal of Systems and Control Engineering ◽

10.1177/0959651818813221 ◽

2018 ◽

Vol 233 (4) ◽

pp. 431-440

Author(s):

Andrzej Rysak ◽

Magdalena Gregorczyk

Keyword(s):

Magnetic Field ◽

Time Series ◽

Hysteresis Loops ◽

Bias Field ◽

Homogeneous Magnetic Field ◽

Operating Conditions ◽

Bias Magnetic Field ◽

Linear Dynamics ◽

Non Linear ◽

Magnetostrictive Devices

Investigations of systems with an active magnetostrictive element generally assume the presence of an external homogeneous bias magnetic field. This article, however, presents the results of a study investigating a bimorph magnetostrictive-aluminium beam vibrating in a non-homogeneous bias field. By comparing results obtained under different operating conditions of the system, the combined effect of the non-linear beam stress and the non-homogeneous external magnetic field on the dynamics of the Villari phenomenon is determined. The preliminary results prove that the application of non-linear magnetic fields to the magnetostrictive devices ensures the extension of energy harvesting bandwidth of these devices and can be used to improve their control possibilities. A study of time series and hysteresis loops provides more detailed information about the non-linear magnetization and dynamics of the system.

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A Research and Application of the Processing Methods of Railway Measurement Based on Self-Mobile Scanning Measurement System

Advances in Transdisciplinary Engineering - ISMR 2020 ◽

10.3233/atde200235 ◽

2020 ◽

Author(s):

Jiancai Zhang ◽

Hang Mu ◽

Feng Han ◽

Shumin Han

Keyword(s):

Measurement System ◽

High Speed ◽

Automatic Segmentation ◽

Laser Scanner ◽

Region Growing ◽

Image Sensor ◽

Operating Conditions ◽

Secondary Development ◽

Railway Line ◽

Region Growing Segmentation

With the gradual improvement of China’s railway net, the opening of international railways as well as the continuous growth of railway operating mileage, the workload of remeasuring railways is increasing. The traditional methods of remeasuring railways can not meet current high-speed and high-density operating conditions anymore in terms of safety, efficiency and quality, so a safer and more efficient measurement method is urgently needed.This thesis integrated various sensors on a self-mobile instrument, such as 3D laser scanner, digital image sensor and GNSS_IMU, designing a set of intelligent and integrated self-mobile scanning measurement system. This thesis proposed region growing segmentation based on the reflection intensity of point cloud. Through the secondary development of CAD, the menu for automatic processing of self-mobile scanning measurement system is designed to realize rail automatic segmentation, extraction of rail top points, fitting of plane parameters of railway line, calculation of curve elements and mileage management.The results show that self-mobile scanning measurement system overcomes the shortcomings of traditional railway measurement to some extent, and realizes intelligent measurement of railways.

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Modelling and control of greenhouse system using neural networks

Transactions of the Institute of Measurement and Control ◽

10.1177/0142331216670235 ◽

2016 ◽

Vol 40 (3) ◽

pp. 918-929 ◽

Cited By ~ 11

Author(s):

A Manonmani ◽

T Thyagarajan ◽

M Elango ◽

S Sutha

Keyword(s):

Neural Network ◽

Neural Networks ◽

Moving Average ◽

Growth Conditions ◽

Operating Conditions ◽

Adverse Weather ◽

Control Schemes ◽

Non Linear ◽

Auto Regressive ◽

And Control

A greenhouse system (GHS) is a closed structure that facilitates modified growth conditions to crops and provides protection from pests, diseases and adverse weather. However, a GHS exhibits non-linearity due to the interaction between the biological subsystem and the physical subsystem. Non-linear systems are difficult to control, particularly when their characteristics change with time. These systems are best handled with methods of computation intelligence, such as artificial neural networks (ANNs) and fuzzy systems. In the present work, the approximation capability of a neural network is used to model and control sufficient growth conditions of a GHS. An optimal neural network-based non-linear auto regressive with exogenous input (NARX) time series model is developed for a GHS. Based on the NARX model, two intelligent control schemes, namely a neural predictive controller (NPC) and non-linear auto regressive moving average (NARMA-L2) controller are proposed to achieve the desired growth conditions such as humidity and temperature for a better yield. Finally, closed-loop performances of the above two control schemes for servo and regulatory operations are analysed for various operating conditions using performance indices.

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