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In recent years, the issue of electronic waste production has gained significant attention. To mitigate the environmental impact of e-waste, one approach under consideration involves the development of biodegradable electronic devices or devices that dissolve in the environment at the end of their life cycle. This study presents results related to the creation of a sensor that effectively addresses both criteria. The device was constructed using a composite material formed by impregnating a pullulan membrane (a biodegradable water-soluble biopolymer) with 1-Ethyl-3-Methylimidazolium tetrafluoroborate (a water-soluble ionic liquid) and coating the product with a conductive silver-based varnish. Capitalizing on the piezoionic effect, the device has demonstrated functionality as a vibration sensor with a sensitivity of approximately 5.5 × 10−5 V/mm and a resolution of about 1 mm. The novelty of this study lies in the unique combination of materials. Unlike the use of piezoelectric materials, this combination allows for the production of a device that does not require an external potential difference generator to function properly as a sensor. Furthermore, the combination of a biopolymer, such as pullulan, and an ionic liquid, both readily soluble in water, in creating an active electronic component represents an innovation in the field of vibration sensors. [ABSTRACT FROM AUTHOR]

In recent years, the issue related to electronic waste production has been gaining prominence. One of the approaches considered to limit the impact of e-waste on the environment involves the development of biodegradable electronic devices or devices that dissolve in the environment at the end of their life cycle. In this study, we present the preliminary results related to the creation of a sensor that could meet both criteria. The device was constructed using a composite material obtained by impregnating a membrane of polycaprolactone (a biodegradable polymer) with 1-Ethyl-3-Methylimidazolium tetrafluoroborate (a water-soluble ionic liquid), which was coated with a conductive silver-based varnish. Leveraging the piezoionic effect, the device has been proven to function as a vibration sensor with a sensitivity of approximately 1.9 × 10−5 V/mm and a resolution of about 0.15 mm. [ABSTRACT FROM AUTHOR]

Bio-derived polymers are promising materials for the development of eco-friendly sensors. Composites, composed of bacterial cellulose sheets sandwiched between two layers of conducting polymers and infused with ionic liquids, exhibit generating properties when utilized as deformation sensors. The composite material underwent a frequency analysis to explore the relationship between the transduction property and the frequency of the applied mechanical deformation. A model identification was performed using the acquired experimental data. The linearity of the system was examined, and the findings show that a second-order system, adequately approximates the system's dynamics. [ABSTRACT FROM AUTHOR]

Assistive Technology helps to assess the daily living and safety of frail people, with particular regards to the detection and prevention of falls. In this paper, a comparison is provided among different strategies to analyze postural sway, with the aim of detecting unstable postural status in standing condition as precursors of potential falls. Three approaches are considered: (i) a time-based features threshold algorithm, (ii) a time-based features Neuro-Fuzzy inference system, and (iii) a Neuro-Fuzzy inference fed by Discrete-Wavelet-Transform-based features. The analysis was performed across a wide dataset and exploited performance indexes aimed at assessing the accuracy and the reliability of predictions provided by the above-mentioned strategies. The results obtained demonstrate valuable performances of the three considered strategies in correctly distinguishing among stable and unstable postural status. However, the analysis of robustness against noisy data highlights better performance of Neuro-Fuzzy inference systems with respect to the threshold-based algorithm. [ABSTRACT FROM AUTHOR]

In this paper, an environmentally friendly inertial motion sensor is investigated, modelled, and characterized as an accelerometer. The sensor is obtained by using bacterial cellulose (BC) as a base biopolymer. BC is then impregnated with ionic liquids. Electrodes are realized by a conducting polymer, in a typical three-layer structure. The sensor works in a cantilever configuration and produces an open voltage signal as the result of a flexing deformation. A model is proposed for the transduction phenomenon. The composite mechano-electric transduction capability is exploited for realizing the accelerometer. Results of the chemical and transduction characterization of the accelerometer are reported. Finally, experimental evidence of the possible nature of the transduction phenomenon is given. [ABSTRACT FROM AUTHOR]

Nowadays there is an increasing request to realize green, eco-friendly, and biodegradable electronic devices for biosensor implementation. In this context, we have conceived and realized a green sensor based on localized surface plasmon resonance (LSPR) phenomenon in a thin-slab waveguide of bacterial cellulose (BC). These LSPR sensors can be obtained simply by gold sputtering on the slab BC waveguides. The performances have been studied investigating the presence of ionic liquids (ILs) inside and in absence of ILs with various thicknesses of the BC substrate. Depending of the thickness of the BC layer, the ILs effect on the LSPR can be constructive or destructive. In this work, we present a study of the sensor performances, in terms of bulk sensitivity and resolution by changing the aforementioned parameters. Analyses in terms of BC geometry are pursued in order to improve the interaction between the light and the LSPR phenomenon. The experimental setup used for this kind of extrinsic optical fiber LSPR sensor is based on two optical fibers used to connect a white light source and a spectrometer with the green LSPR sensor chip. Results evince the suitability of the proposed approach in order to realize sensors and biosensors with several intriguing properties and features. In fact, these LSPR platforms could be used to realize disposable biosensors, when a specific bioreceptor is covalently bonded to the gold. [ABSTRACT FROM AUTHOR]

In this article, a generating all-polymeric touchpad is proposed. The system is based on a novel class of composites, named ionic polymer–polymer composites. The composites exploit the migration of mobile ions inside a three-layer membrane for generating an electrical signal when deformed. The touchpad consists of two sensors, which bend according to the touching point. The signals produced by the two sensors are conditioned by using a differential configuration, providing a symmetric output voltage. In this article, the working principle is described and modeled. Then, the realization of a prototype is shown in detail. Finally, the results of a measuring survey, performed to obtain touchpad characterization, are given. The proposed system demonstrates the possibility of realizing next-generation polymer-based devices for motion measurements. [ABSTRACT FROM AUTHOR]

The diffusion of electronics in everyday life requires for the development of sensing systems, based on new materials and technologies. Deformation sensors are of interest in many application fields, ranging from assisted rehabilitation, virtual reality and augmented reality, and gaming applications, juts to mention a few. The diffusion of low-cost sensing systems outlines the need for environmentally friendly and low-cost sensors. Cellulose is one of the most abundant materials on earth. Eventually, it is green, cheap, and flexible. In this article, the deformation sensing properties of a three-layer structure-based bacterial cellulose (BC) compound based on BC, impregnated by ionic liquids, and covered by conducting polymers are investigated. More specifically, it is shown that this novel composite is capable of sensing flexural deformations and producing a corresponding open-circuit voltage. The obtained results pave the road to the possibility of realizing a new class of deformation sensors that fit the requirements of more sustainable sensor technologies. [ABSTRACT FROM AUTHOR]

The implementation of Industry 4.0 and IoT will require the availability of large-mass production electronics. The infusion of intelligence, required for realizing smart grids, cities, homes, and cars, just to mention a few, will encourage the ubiquitous diffusion of electronics in everyday life. Think, e.g., to the evolution of cellular phone complexity, or of smart domestic appliances. The need for intelligent applications will not be limited to our cities or homes. Precise agriculture will, e.g, require a massive diffusion of smart devices, which will be required for monitoring the wellness of each plant. In a similar way, smartness is required for the continuous monitoring of the healthiness and safety of large infrastructures such as dams or viaducts, just to mention a few. [ABSTRACT FROM AUTHOR]

This paper introduces a soft sensor (SS) for the estimation of the deflection of a polymeric mechanical actuator. The actuator is based on ionic polymer-metal composites (IPMCs). Applications of IPMCs have been proposed in fields such as robotics, surgery, and aerospace, to mention the most interesting ones. In such application fields, both the complexity and the size of the actuating system are of chief importance. An SS can be, therefore, preferred to hardware measuring the actuator output, for estimating the actuator motion. Also, low-order models are of interest to limit the computational load, which can be a constraint in real-time applications. To this aim, several data-driven nonlinear finite-impulse response (NFIR) models have been investigated. Data, used for the model identification, have been acquired, in controlled environmental conditions, by using swept signals as the input to the IPMC actuator. Linear and nonlinear models, based on principal component analysis, shallow, and deep neural networks (NNs), have been investigated, for different model orders. The best results have been obtained by an SS based on a fifth-order NFIR model, implemented by a deep belief NN. [ABSTRACT FROM AUTHOR]

A novel optical platform has been used to monitor the interaction between a molecularly imprinted polymer (MIP) and a small molecule. The new optical sensor is made of a polyethylene terephthalate substrate with a pattern of silver nanoparticles, printed on it by inkjet technology, and two plastic optical fibers (POFs). The POFs connect the optical sensor, later covered by the MIP layer, with a light source and with a spectrometer. The detection of furfural (furan-2-carbaldehyde, 2-FAL) in aqueous media was investigated exploiting a selective MIP receptor. The experimental results show that this novel approach presents a limit of detection of about 0.03 ppm, comparable to that of plasmonic sensors combined with the same MIP, but with the advantage of an easier preparation procedure. [ABSTRACT FROM AUTHOR]

Beam diagnostic and especially beam current measurements represent a key aspect in the production of a high-quality beam. Due to the known interplay between beam current and beam and plasma properties, many solutions have been addressed to solve this need. Although precise beam current measuring systems exist, they cannot provide noninvasive solutions for the measurement of very low-frequency currents in electron cyclotron resonance ion source (ECRIS) beamline, with a range from tens to hundreds of microamperes. To address the above-mentioned needs, this paper proposes an indirect measurement methodology based on the estimation of the magnetic field produced by target current exploiting a residence time difference fluxgate and a flux concentrator (a mechanical structure able to constrain produced magnetic field in a given area). The main advantage of this approach is related to the possibility to perform a noninvasive current measurement. An optimal geometry for the flux concentrator has been investigated by using a finite-element method analysis that has led to the definition of a minimum value of the magnetic field generated by the minimum value of the target current, around $5.0~\mu \text{A}$ , equal to 3.07 nT. To assess the solution, an experimental setup, miming real magnetic flux intensity inside ECRIS beamlines, has been realized. The measuring strategy has a magnetic resolution of 1 nT and a current resolution of $1.6~\mu \text{A}$ , that is, in line with requirements. Results obtained demonstrate the suitability of the measurement system for the specific application addressed in this paper, both in terms of operating range and resolution. [ABSTRACT FROM AUTHOR]

Electro-active polymers (EAPs) are soft polymers that develop mechanical strain if subjected to electrical stimuli or, on the contrary, produce voltages if mechanically deformed. Their discovery has led to take into account their possible use as sensor-actuator for both bio-mimetic applications and traditional robotics. Ionic polymer-metal composites (IPMCs) and ionic polymer-polymer composites (IP2Cs) belong to EAPs. Both of them are fabricated starting from an ionic polymer (typically Nafion®117) but while in IPMCs the electrode is based on a metal (Ag, Au or Pt), IP2Cs are all-organic devices: in fact a conducting polymer (e.g., poly(3,4-ethylendioxytiophene)-polystyrenesulfonate, PEDOT/PSS) is used as the electrode. In this work, a comparison has been done among the fabrication processes and the mechanical, thermal and electromechanical behaviour of IPMCs and IP2Cs. The objective is to investigate the influence of the kind of electrode on the final properties of the devices, taking, also, into account the effect of different solvents, used for realizing the actuation process (H2O or Ethylene Glycol). Reported results show that the performance of the obtained devices are function of manufacture parameters, the kind of electrode and solvent; consequently, taking into account the possible application, it is possible to choose the device that better meets specific requirements. [ABSTRACT FROM AUTHOR]

Power electronic modules are realized by integrating several semiconductor chips inside one package. In this paper, a new thermal modeling procedure and its application to a power electronic module are presented. The adopted modeling strategy consists of the derivation of numerical thermal impedances by 3-D finite element models, validated by comparison with available experimental data, and of the coefficients identification of the \(RC\) passive network, through a specific topology, here introduced, to obtain a lumped parameter model of the thermal behavior of the module. [ABSTRACT FROM AUTHOR]

Ionic polymer-polymer composites (IP^2Cs) are electroactive polymers which can be used both as sensors and as actuators. In this paper, a new multiphysics model of IP^2Cs working as an actuator is presented and implemented using a finite element methods solver (COMSOL Multiphysics). The model involves electrical, mechanical, chemical, and thermal effects and yields a unique solution. Knowledge acquired by measuring campaigns has been included in the model. More specifically the frequency dependence of Young's modulus was experimentally determined and introduced in such a model. A frequency-domain investigation is performed and a model optimization procedure that integrates the Nelder-Mead simplex method with the COMSOL Multiphysics models is exploited to identify IP^2C model parameter by fitting experimental data. A fractional order dynamics has been identified in the model, confirming previous studies on IPMC gray box modeling and on electroactive polymeric devices. [ABSTRACT FROM PUBLISHER]

Smart systems adapt to the surrounding environments in a number of ways. They are capable to scavenge energy from available sources, sense and elaborate external stimuli and adequately react. Electro Active Polymers are playing a main role in the realization of smart systems for applications if fields such as bio inspired and autonomous robotics, medicine, and aerospace. This paper focus on the possibility to use Ionic Polymer Metal Composites as a class of materials relevant to the realization of post silicon smart systems. The three main aspects of this new technology, i.e., fabrication methods, modeling, and applications are described with emphasis to most recent results. Attention is given to main challenges and shortcomings to be solved for technology, modelling, and control of IPMC based devices that need to be solved before this new technology can be fully exploited in real world applications. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2013 [ABSTRACT FROM AUTHOR]

A model of a new class of total polymeric sensors known as ionic polymer–polymer composite (IP^2C) has been developed. Starting from a previous model, new experimental investigations have been performed in order to increase the significance of the sensor model. The device uses Clevios P HC V4 electrodes and a conducting polymer, produced and distributed by Heraeus. The sensing behavior of IP^2Cs has been modeled by applying a suitable set of deforming signals and using a data-driven identification procedure. The sensor model has been investigated in a suitable range of working frequencies by using an ad hoc realized setup. Also, Young's modulus of IP^2Cs has been measured by means of the dynamic mechanical analysis and the results have been used in the identification of the IP^2Cs sensor model. The model identification and validation have been performed by using a programmable mechanical vibration generator system, and experimental evidence of the suitability of the proposed model is given in this paper. [ABSTRACT FROM AUTHOR]

In this paper, a seismic sensor based on the combination of ionic polymer metal composite (IPMC) and ferrofluids is presented. The device consists of a vial, filled with ferrofluid, housing an IPMC cantilever beam sensor. Considering that the behavior (e.g., frequency response) of a beam immersed in a fluid changes with the fluid density, in this paper, a novel methodology is proposed to implement a mechanism allowing for the active tuning of the sensor specifications (such as operating range, frequency behavior, and responsivity). To such aim, the addressed methodology exploits external magnetic fields to modify the density of the ferrofluid in which the IPMC sensor is immersed. A description of the sensing methodology and the realization of the sensor prototype are given along with experimental results confirming the expected behavior of the device. Moreover, a model is presented which can be used to predict the IPMC behavior as a function of the fluid properties. [ABSTRACT FROM AUTHOR]

Ionic polymer metal composites (IPMCs) are electroactive materials made of ionic polymer thin membranes with platinum metallization on their surfaces. They are interesting materials due to not only their electromechanical applications as transducers but also to their electrochemical features and the relationship between the ionic/solvent current and the potential field. Their electrochemical properties thus suggest the possibility for exploiting them as compact fractional-order elements (FOEs) with a view of defining fabrication processes and production strategies that assure the desired performances. In this paper, the experimental electrical characterization of a brand new IPMC setup in a fixed sandwich configuration is proposed. Two IPMC devices with different platinum absorption times (5 h and 20 h) are characterized through experimental data: first, a preliminary linearity study is performed for a fixed input voltage amplitude in order to determine the frequency region where IPMC can be approximated as linear; then, a frequency analysis is carried out in order to identify a coherent fractional-order dynamics in the bode diagrams. Such analyses take the first steps towards a simplified model of IPMC as a compact electronic FOE for which the fractional exponent value depends on fabrication parameters as the absorption time. [ABSTRACT FROM AUTHOR]

In this paper, the characterization of ionic polymer–metal composite (IPMC)-based sensors, for possible applications related to biological systems, with respect to the influence of environmental temperature and relative humidity is investigated. This paper is second in a row devoted to the characterization of IPMC transducers with respect to the aforementioned influencing quantities. The characterization is performed by statistically investigating sensing signals in typical working conditions, and the experiments performed show that, for the investigated ranges, the effects of relative humidity are much more evident than the corresponding effects produced by temperature changes. The results reported give information that integrated IPMC transducer models, which are introduced so far, contribute to better exploit this novel technology. [ABSTRACT FROM PUBLISHER]

In this paper, a vibrating tactile probe is presented. The probe exploits the dependence of its resonant frequency on the varying load and hence on the contacted material. This methodology allows the recognition of different materials by observing the electrical quantities involved in the probe dynamics. More specifically, two ionic polymer-metal composite (IPMC) strips are used, one as actuator and one as sensor, that work together for the recognition of materials. The actuator forces the system into resonant conditions that, as stated before, change with the mechanical properties of the contacted material. The output signal produced by the IPMC sensor contains the information required for the estimation of the contacting material. The sensing capabilities could be exploited in various biomedical applications, such as catheterism and surgical resection of tumors. The model and the experimental validation of the proposed probe are reported. For each material, different surveys were collected to estimate the uncertainty of the resonant frequency and hence to obtain the characteristic diagram of the device along with its uncertainty. The reported results show that the developed probe can be used to distinguish among different materials. [ABSTRACT FROM AUTHOR]

Several models that describe the behavior of ionic polymer-metal composite (IPMC)-based actuators can be found in the literature. The response of IPMC transducers as a function of modifying quantities is a matter of interest; however, it has not been investigated. It is reasonable to argue that environmental humidity and temperature represent the main modifying parameters. In fact, humidity changes the behavior of IPMC transducers, working as both sensors and actuators, because it changes the Young modulus of the devices and, hence, their mechanical response. The influence of temperature is suspected, because polymer characteristics are often influenced by this quantity. In a previous paper, the authors proposed a dynamic model and investigated the scaling effect of geometrical parameters, giving evidence of the excellent agreement between estimations that were obtained using the proposed model and corresponding observations. In this paper, the response of IPMC actuators to both temperature and relative humidity is analyzed, giving interesting information that both integrates IPMC models and allows for a better exploitation of IPMCs. [ABSTRACT FROM AUTHOR]

A new class of materials called ionic polymerpolymer composites has been investigated to demonstrate the sensing and acting capabilities of these all-organic structures. Samples have been realized by covering Nafion membranes, with Orgacon 3040 conducting polymer as electrode material. Membranes whose electrodes were manufactured using the drop-casting technique exhibited the best electromechanical performances. Sensors have been tested in a dedicated experimental setup to model their electromechanical transduction behavior. Thus, the obtained model has been validated. [ABSTRACT FROM AUTHOR]

The development of electronic sensing devices for the visually impaired requires knowledge of the needs and abilities of this class of people. This paper presents a rough analysis that can be used to properly define the criteria to be adopted for the design of such devices. In particular, attention will be focused on clear-path indicators, highlighting their role in orientation and mobility tasks. A new device belonging to this class is presented. The detector is based on a multisensor strategy and adopts smart signal processing to provide the user with suitable information about the position of objects hindering his or her path. Experimental trials demonstrate the efficiency of the device developed. [ABSTRACT FROM AUTHOR]

This paper analyzes a number of strategies that are devoted to improving the generalization capabilities of neural- network-based soft sensors when only small data sets are available. The aim of this paper is to search for a strategy that is able to cope with the problem of scarcity of experimental data, which often arises in industrial applications. The strategies that are considered are based on the manipulation of experimental training data sets to increase their diversity either by injecting noise into the available data or by using the bootstrap resampling approach. A new method, which is based on an aggregation of neural models, trained on different training data sets, which are obtained by noise injection and bootstrap resampling, is proposed in this paper. The methods considered were compared in an industrial case study regarding the design of a backup soft sensor for a thermal cracking unit, working in a refinery in Sicily, Italy. The results of the case study show that all the methods considered produced an improvement in the estimation capability of the models. The best performance was obtained by using the method proposed by the authors. [ABSTRACT FROM AUTHOR]

Ferroelectrics are suitable for the realization of sensors because their characteristics depend on modifying quantities such as temperature, electric fields, and pressure. The dependence of the dielectric and pyroelectric constant of ferroelectric materials on temperature is large and close to the Curie temperature, and this behavior can be exploited for the realization of capacitive sensors with high sensitivity in such a range of temperature. In this paper, a convenient solution for the investigation of the dielectric and pyroelectric coefficients of a ferroelectric device is discussed, along with a characterization tool developed to measure them. The architecture adopted was developed to study the aforementioned material properties up to the Curie temperature. A general- purpose data acquisition card and instruments usually available in research and educational laboratories were used, thus guaranteeing the low-cost feature, easy reproducibility, and flexibility. [ABSTRACT FROM AUTHOR]

Hysteresis is a common phenomenon in nonlinear systems. Piezoelectric bimorphs show hysteretic behavior when operating as actuators. Tools that produce the characterization of these devices are available; they use high-cost setups that measure deformations with resolutions on the order of nanometers. In this paper, a new low-cost experimental setup that uses coupled infrared detectors to investigate the behavior of piezoelectric actuators is discussed. The tool, providing deformation measurements with a resolution on the order of 10 , is intended to produce a rough estimation of the device behavior and is of interest for research and educational purposes. Low cost, easy reproducibility in research and educational laboratories, a contactless measurement strategy, an inset calibration facility, and a suitable user interface are the main features of the tool developed. Notes on the uncertainty introduced by the tool when estimating bimorph deformations are given. Moreover, a case study that concerns the characterization of a piezoelectric bimorph actuator is discussed to illustrate the performance of the system developed in a real case. [ABSTRACT FROM PUBLISHER]

In this paper, a virtual instrument for the estimation of octane number in the gasoline produced by refineries is introduced. The instrument was designed with the aim of replacing measuring hardware during maintenance operations. The virtual instrument is based on a nonlinear moving average model, implemented by using multilayer perceptron neural networks. Stacking approaches are adopted to improve the estimation performance of the instrument. Classical linear algorithms of model aggregation are compared in the paper with a nonlinear strategy, based on the neural combination of a set of first-level neural estimators. The validity of the proposed approach is verified by comparison with the performance of both linear and nonlinear modeling techniques. The designed virtual instrument has been implemented by a large refinery in Sicily, which supplied the data used during the design phase. [ABSTRACT FROM AUTHOR]

High-performance models are required during the design (phase) of sensing devices in order to take their physical behavior into account and to include these models in calculations and simulations aimed at optimizing the performance of devices in fixed operating conditions. In this paper, the problem of model fitting for ferroelectric devices is addressed; in particular, a model of the behavior of a ferroelectric capacitor is accomplished. The static behavior of such devices is investigated, and an experimental setup for both characterization and model estimation is proposed. The model obtained is assessed, and the uncertainty introduced by the measurement system is estimated. [ABSTRACT FROM AUTHOR]

This paper presents an innovative wormlike robot controlled by cellular neural networks (CNNs) and made of an ionic polymer-metal composite (IPMC) self-actuated skeleton. The IPMC actuators, from which it is made of, are new materials that behave similarly to biological muscles. The idea that inspired the work is the possibility of using IPMCs to design autonomous moving structures. CNNs have already demonstrated their powerfulness as new structures for bio-inspired locomotion generation and control. The control scheme for the proposed IPMC moving structure is based on CNNs. The wormlike robot is totally made of IPMCs, and each actuator has to carry its own weight. All the actuators are connected together without using any other additional part, thereby constituting the robot structure itself. Worm locomotion is performed by bending the actuators sequentially from ‘tail’ to ‘head,’ imitating the traveling wave observed in real-world undulatory locomotion. The activation signals are generated by a CNN. In the authors' opinion, the proposed strategy represents a promising solution in the field of autonomous and light structures that are capable of reconfiguring and moving in line with spatial-temporal dynamics generated by CNNs. [ABSTRACT FROM AUTHOR]

Ferroelectric materials show the hysteresis effect; in particular, with a zero field there are two equally stable states of polarization ±Pr allowing for the design of a binary-state device in the form of a ferroetectric capacitor (metal ferroelectric-metal) that can be reversed electrically. The characterization of ferroelectric devices consists of determining the hysteresis behavior and ±Pr quantities. Industrial equipment for producing this kind of characterization is expensive, and complex systems are needed for specific tasks. This paper proposes a low-cost tool for addressing the properties of ferroelectric devices, which is useful for qualitative investigation in research laboratories. [ABSTRACT FROM AUTHOR]

In the field of measurement nonlinear behavior is typical of a large set of sensors (mechanical, electrical, pneumatic, and so on). In several devices, SQUID and piezoelectric sensors being very well-known examples, the nonlinearity is strictly correlated to the hysteresis phenomenon, which can be described by introducing the quartic double well (QDW) potential in the system model. The analysis addresses the influence of potential characteristics on the performance of hysteretic measuring devices. A Brownian system with a QDW potential is used as a general prototype of hysteretic phenomena. This paper applies to the general class of hysteretic devices forced with low-amplitude signals and gives suitable out lines for the design of several measuring devices. [ABSTRACT FROM AUTHOR]

Real laboratory experiments can help students to gain a better understanding of theoretical problems. Great efforts are needed, however, to improve the quality of laboratory sessions, and a large number of tutors are usually required. Moreover, students may lose time because of hardware failure or an inefficient experimental setup. Several educational tools (based on virtual instruments) have been developed allowing for optimized time scheduling and remote access to laboratory sessions. Drawbacks related to hardware failure have not, however, been seriously addressed. This paper proposes an educational tool made up of a user-friendly interface controlling experimental boards. It basically consists of an array of optical sensing devices connected to suitable conditioning circuits, which are interfaced to a virtual instrument by means of a data acquisition system. To solve the previously mentioned drawbacks, a solution based on both pre-cabled hardware and PC-based measurement stations has been adopted. Moreover, the ability to configure self-educational tasks optimizes time scheduling for students during laboratory activities. The proposed system allows students to improve their knowledge in the field of optical sensing devices, virtual instrumentation, data acquisition systems, and signal processing. The paper describes an application of the tool as a simple system for surface recognition. This application is one of the laboratory tasks performed in measurement classes during this engineering course at the University of Catania, Catania, Italy. [ABSTRACT FROM AUTHOR]

Introduces a novel instrument for the detection of stochastic resonance (SR) conditions that does not require any human intervention and allows independent validation of results concerning SR. Overview of optimization theory; Tracing the ISO-amplitude and ISO-STD curves; Conclusion.

Discusses an innovative solution for a conditioning system that is highly suitable for low-cost metal organic-chemical vapor deposition (MO-CVD) reactors. Overview of MO-CVD system; Influencing parameter control; Experimental results; Some notes on the accuracy of the whole system.

Presents information on a study which proposed a procedure to determine the parameters that influence the optimal level of the noise assuring suitable performances. Methodology of the study; Results and discussion on the study; Conclusion.

The notion of noise-activated systems has been well known since the 1950s. A number of natural phenomena have been investigated by means of this theory and an improvement in the performance of several systems has also been achieved. Recently the stochastic resonance (SR) phenomenon was introduced as an innovative approach for both understanding the behaviour and improving the performance of several classes of systems. In the present work some new results regarding the influence of forcing signal parameters on the persistence of the SR condition are given. Both theoretical results and numerical simulations have been carried out to emphasize the suitability of the proposed noise tuning methodology. [ABSTRACT FROM AUTHOR]