Analog Electronics Research Articles

Cuff Pressure Pain Detection Is Associated with Both Sex and Physical Activity Level in Nonathletic Healthy Subjects.

The aim of this study was to evaluate pressure pain sensitivity on leg and arm in 98 healthy persons (50 women) using cuff algometry. Furthermore, associations with sex and physical activity level were investigated. Normal physical activity level was defined as Godin Leisure-Time Exercise Questionnaire (GLTEQ) score ≤ 45 and high activity level as GLTEQ > 45. A pneumatic double-chamber cuff was placed around the arm or leg where a single chamber was inflated. The cuff inflation rate (1 kPa/s) was constant, and pain intensity was registered continuously on a 10 cm electronic visual analogue scale (VAS). The pain detection threshold (PDT) was defined as when the pressure was perceived as painful, and pain tolerance (PTT) was when the subject terminated the cuff inflation. For PTT, the corresponding VAS score was recorded (VAS-PTT). The protocol was repeated with two chambers inflated. Only single cuff results are given. For women compared with men, the PDT was lower when assessed in the arm ( P = 0.002), PTTs were lower in the arm and leg ( P < 0.001), and the VAS-PTT was higher in the arm and leg ( P < 0.033). Highly active participants compared with less active had higher PDT ( P = 0.027) in the leg. Women showed facilitated spatial summation ( P < 0.014) in the arm and leg and a steeper VAS slope (i.e., the slope of the VAS pressure curve between PDT and PPT) in the arm and leg ( P < 0.003). This study indicates that reduced pressure pain sensitivity is associated both with male sex and physical activity level.

Empirical Analysis of the Use of the VISIR Remote Lab in Teaching Analog Electronics

Remote laboratories give students the opportunity of experimenting in STEM by using the Internet to control and measure an experimental setting. Remote laboratories are increasingly used in the classroom to complement, or substitute for, hands-on laboratories, so it is important to know its learning value. While many authors approach this question through qualitative analyses, this paper reports a replicated quantitative study that evaluates the teaching performance of one of these resources, the virtual instrument systems in reality (VISIR) remote laboratory. VISIR, described here, is the most popular remote laboratory for basic analog electronics. This paper hypothesizes that use of a remote laboratory has a positive effect on students’ learning process. This report analyzes the effect of the use of VISIR in five different groups of students from two different academic years (2013–2014 and 2014–2015), with three teachers and at two educational levels. The empirical experience focuses on Ohm’s Law. The results obtained are reported using a pretest and post-test design. The tests were carefully designed and analyzed, and their reliability and validity were assessed. The analysis of knowledge test question results shows that the post-test scores are higher that the pretest. The difference is significant according to Wilcoxon test ( ${p} ), and produces a Cohen effect size of 1.0. The VISIR remote laboratory’s positive effect on students’ learning processes indicates that remote laboratories can produce a positive effect in students’ learning if an appropriate activity is used.

New Position Algorithms for the 3D CZT Drift Detector

The 3-D position sensitive CZT detector for high-energy astrophysics developed at DTU has been investigated with a digitizer readout system. The 3-D CZT detector is based on the CZT drift-strip detector principle and was fabricated using a REDLEN CZT crystal (20 mm $\times20$ mm $\times5$ mm). The detector contains 12 drift cells, each comprising one collecting anode strip with four drift strips, biased such that the electrons are focused and collected by the anode strips. Three-dimensional position determination is achieved using the anode strip signals, the drift-strip signals, and the signals from ten cathode strips. For the characterization work, we used a DAQ system with a 16 channels 250-MHz 14-b digitizer, SIS3316. It allowed us to analyze the pulse shapes of the signals from four detector cells at a time. The 3-D CZT setup was characterized with a finely collimated radioactive source of 137Cs at 662 keV. The analysis required development of novel position determination algorithms which are the subject of this paper. Using the digitizer readout, we demonstrate improved position determination compared to the previous read out system based on analog electronics. Position resolutions of 0.4-mm full width at half maximum (FWHM) in the $x$ -, $y$ -, and $z$ -directions were achieved and the energy resolution was 7.2-keV FWHM at 662 keV. The timing information allows identification of multiple interaction events within one detector cell, e.g., Compton scattering followed by photoelectric absorption. These characteristics are very important for a high-energy spectral-imager suitable for use in advanced Compton telescopes, or as focal detector for new hard X-ray and soft $\gamma$ -ray focusing telescopes or in polarimeter instrumentation. CZT detectors are attractive for these applications since they offer relatively high-quantum efficiency. From a technical point of view it is advantageous that their cooling requirements are modest.

Promoting Peer Assisted Learning and Developing Leaders

Here the efforts of ensuring the effectiveness of team based activity planned under the course Analog and Digital Electronics (ADC) involving Peer Assisted Learning are presented. Course concepts can be effectively conveyed to students by solving problems on a regular basis. The course ADC is an important course under Automation&Robotics program providing fundamental concepts which are prerequisites for studying the higher end subjects prescribed under the program. Developing the skill of problem solving and analysis is the critical need of the course. This was taken up as the objective wherein a team based activity was designed for promoting a high level peer to peer interaction involving students from different grades forming a team to solve problems, analyze the result and summarize. The activity was designed to promote cooperative learning environment in turn boosting the confidence level and problem solving ability of students in a phased manner. The challenge was to address the needs in a justifying manner for the weaker and lagging students. Emphasis is also on building some specialized skills like leading the team, owing responsibility of the team, demonstrating interpersonal skills, developing team spirit and enthusiasm among the set of students chosen as leaders of the activity. Hence the objectives of the proposed activity, process of selecting of leaders, the criteria of forming team, mechanisms introduced to supervise the implementation of the activity on a timely basis, role of faculty coordinator , the results achieved and the analysis of student feedback on the on-going activity are discussed and presented.

Сетевой фронтир как метафора и миф

This article considers spatial metaphors of the Internet and the possibility to extrapolate the frontier thesis of F. Turner on the electronic space. The authors believe that information and communication technologies and the digital world have become new spaces for the expansion of states or individuals. That is why there are ongoing scientific debates on the limits and potential of western and electronic frontiers’ metaphors for analytical description of the digital space. The metaphor of the Internet as a western frontier is quite controversial; many authors prefer the electronic frontier analogy as more heuristic and valid for constructing metaphors of the digital reality. The network frontier is defined as a dynamic, elastic and permeable border of social and cultural practices of the network society. The authors estimate the heuristic potential of the concept ‘network frontier’ developed on the basis of integration of the frontier theory and the concept ‘network society’, taking into account the effects of globalization for the study of elastic, permeable and movable border of the network landscape. In the digital world, the spatiality transforms, the geography of the Internet network determines the metamorphosis of the frontier as a contact zone between online and offline spaces, which is dynamic, innovative, encourages mobility, and its permeability depends on the digital competence of citizens. The authors explain the mythology of western and electronic frontier; name the main network frontier myths related to the rhetoric of western frontier myth; describe the main components of the western frontier myth associated with the idea of American exceptionalism; and conclude with the identification of nowadays myths about frontier-men and the online space they master.

Benchmarking Performance of a Gate-All-Around Germanium Nanotube Field Effect Transistor (GAA-GeNTFET) against GAA-CNTFET

Two gate-all-around field effect transistors (GAA-FETs) based on carbon and germanium nanotubes are proposed. The electronic properties and analog performance of the FETs are theoretically calculated and compared with each other. Also, by adding 5 × 1019 dopant/cm2 doping concentration in the source and drain regions, the results are re-obtained. Non-equilibrium Green's function method within the tight-binding Hamiltonian, which is extracted from density functional theory through the Wannier function, are used to calculate the output results. From the transfer characteristics analysis for nanotubes with the same chirality, it can be found that the ON- and OFF-currents for GeNTFET is about ten times smaller than that of CNTFET. Moreover, by adding dopants in the source and drain regions, the ION increases for both devices. The ION/IOFF ratio for all proposed FETs is almost the same and it is of order 104. We also found that the subthreshold swing for doped CNTFET is smaller than the other examined devices. The output characteristic of the CNTFET shown a saturation current when the drain voltage reached to 0.4 V, while this value for GeNTFET is equal to 0.6 V. Comparison between CNTFET and GeNTFET with the same chirality shows that the CNTFET has a better transistor performance but when comparing is performed on the same diameter of CNT and GeNT FETs, results show better transistor performance of GeNTFET compared to the CNTFET.

Signal Model-Based Fault Coding for Diagnostics and Prognostics of Analog Electronic Circuits

Analog circuits have been extensively used in industrial systems, and their failure may make the systems work abnormally and even cause accidents. In order to monitor their status, detect faults, and predict their failure early, this study proposes a signal model-based fault coding to monitor the circuit response after being stimulated to perform a fault diagnosis without training a large amount of sample data and fault classifiers. Manifold features extracted from circuit responses are associated with a fault-indicating curve in the feature space, in which a group of fault bases are uniformly and continuously distributed along with gradual deviation from the nominal value of one critical component. These bases can be deployed in a factory setting but used during field operation. Fault coding is converted to a novel optimization problem, and the optimized solution forms a fault code representing fault class, suitable for realizing fault detection, and isolation for different components. A fault indicator based on comparison between fault codes can describe performance degradation trends. To improve the prediction accuracy, historical degradation data are collected and considered as a priori exemplars, and a novel exemplar-based conditional particle filter is proposed to track a degradation process for the prediction of remaining useful performance. Case studies on two analog filter circuits demonstrate that the proposed method achieves relatively high fault diagnosis and prognosis accuracy. The main advantages of our study are two-fold: first, the high diagnostic accuracy can still be obtained even if there is no large amount of training data; second, the prognostic effect remains relatively stable whenever triggering prognosis module.

Method of Traffic Safety Enhancement with Use of RFID Technologies and its Implementation

A new solution for the problem of traffic safety regulation with use of RFID technologies is suggested. Traffic safety enhancement is achieved by polling with a modulated radio signal of all electronic analogues of traffic signs and traffic lights representing RFID markings duplicating main traffic signs and traffic lights and located on them directly or nearby. Polling is performed with a radio signal from a transmitter/receiver unit (radar) focused on a narrow zone of radiation action. The suggested method as distinct from the known ones allows for active control of traffic speed in high-risk areas, elimination of the risk of traffic movement along tram rails, pavements and bus lanes as well as for stopping a car when police chases an offender.

Stabilization of a Network of the FitzHugh–Nagumo Oscillators by Means of a Single Capacitor Based RC Filter Feedback Technique

We suggest employing the first-order stable RC filters, based on a single capacitor, for control of unstable fixed points in an array of oscillators. A single capacitor is sufficient to stabilize an entire array, if the oscillators are coupled strongly enough. An array, composed of 24 to 30 mean-field coupled FitzHugh–Nagumo (FHN) type asymmetric oscillators, is considered as a case study. The investigation has been performed using analytical, numerical, and experimental methods. The analytical study is based on the mean-field approach, characteristic equation for finding the eigenvalue spectrum, and the Routh–Hurwitz stability criteria using low-rank Hurwitz matrix to calculate the threshold value of the coupling coefficient. Experiments have been performed with a hardware electronic analog, imitating dynamical behavior of an array of the FHN oscillators.

One Design of an Online Game Based Teaching System Integrated with the Traditional Teaching Resources

Online resource sharing application is already comparatively common in colleges and universities, it assists in teacher teaching and students' self-learning exercises. But, because theory knowledge is difficult to display, tradition teaching resources aren’t suitable for the Analog Electronics course. This paper puts forward a design of the online game based teaching system which can be integrated into the traditional teaching resources.

Readout electronics for a high-resolution soft X-ray spectrometer based on silicon drift detector

The readout electronics for a prototype soft X-ray spectrometer based on silicon drift detector (SDD), for precisely measuring the energy and arrival time of X-ray photons is presented in this paper. The system mainly consists of two parts, i.e., an analog electronics section (including a pre-amplifier, a signal shaper and filter, a constant fraction timing circuit, and a peak hold circuit) and a digital electronics section (including an ADC and a TDC). Test results with X-ray sources show that an energy dynamic range of 1–10 keV with an integral nonlinearity of less than 0.1% can be achieved, and the energy resolution is better than 160 eV @ 5.9 keV FWHM. Using a waveform generator, test results also indicate that time resolution of the electronics system is about 3.7 ns, which is much less than the transit time spread of SDD (<100 ns) and satisfies the requirements of future applications.

A sub-1-volt analog metal oxide memristive-based synaptic device with large conductance change for energy-efficient spike-based computing systems

Nanoscale metal oxide memristors have potential in the development of brain-inspired computing systems that are scalable and efficient. In such systems, memristors represent the native electronic analogues of the biological synapses. In this work, we show cerium oxide based bilayer memristors that are forming-free, low-voltage (∼|0.8 V|), energy-efficient (full on/off switching at ∼8 pJ with 20 ns pulses, intermediate states switching at ∼fJ), and reliable. Furthermore, pulse measurements reveal the analog nature of the memristive device; that is, it can directly be programmed to intermediate resistance states. Leveraging this finding, we demonstrate spike-timing-dependent plasticity, a spike-based Hebbian learning rule. In those experiments, the memristor exhibits a marked change in the normalized synaptic strength (&amp;gt;30 times), when the pre- and post-synaptic neural spikes overlap. This demonstration is an important step towards the physical construction of high density and high connectivity neural networks.

Robust tracking controller for SEPIC drivers

The non-minimum phase, non-linear nature of the SEPIC (single-ended primary inductor converter) makes it very difficult to get robust operating conditions under load variations. Sliding-mode control method is utilised to design a robust controller for tracking control of SEPIC converters for various applications. The implementation of the method is illustrated with the use pulse-width modulation comparators in the control loop to preclude the risk of modulator saturation and to ease the operations. The performance of the SEPIC converter is investigated through numerical simulation and analogue electronics implementation to show the validity, robustness and feasibility of the proposed controller.

Dynamical analysis and electronic circuit realization of an equilibrium free 3D chaotic system with a large number of coexisting attractors

In recent years, a growing interest has been devoted to the design and analysis of chaotic systems without equilibrium point. In the present contribution, we further investigate the dynamics of an equilibrium free 3D chaotic system with quadratic nonlinearities recently introduced by Yan et al. [Optik 127 (2016) 1363–1367]. Standard nonlinear diagnostic tools such as bifurcation diagrams, graphs of largest Lyapunov exponent, phase portraits, frequency spectra and Poincaré sections are plotted to characterize the dynamics of the model in terms of its parameters. It is found that the system experiences a large number of coexisting attractors for some suitable sets of its parameters, depending solely on the choice of initial conditions. Up to twelve coexisting stable attractors are revealed. An electronic analogue of the system is designed and implemented in Pspice. A very good agreement is observed between Spice based simulation results and the theoretical analysis. To the best of the authors’ knowledge, this interesting and singular behavior (i.e. the coexistence of a large number of stable attractors, including periodic, quasi-periodic and chaotic attractors) has not yet been reported both in a third order system and thus deserves dissemination.

Measuring the Mutual Effects of a CZT Detector and a 3T MRI for the Development of a Simultaneous MBI/MRI Insert

A cadmium zinc telluride (CZT) based detector system has been developed with the goal of combining molecular breast imaging (MBI) and magnetic resonance imaging (MRI) to address shortcomings of each modality. The CZT detector system is comprised of four CZT modules tiled in a $2\times 2$ array. Each module consists of 256 pixels ( $16\times 16$ , 2.4 mm pixels) and features a built-in ASIC and FPGA. A custom digital readout circuit board was designed to interface the four modules with a microcontroller to a data acquisition PC. The system was placed within the bore of a 3 T GE Discovery MR750 and imaging performance of each modality evaluated using both sequential and simultaneous imaging protocols. The mean energy resolution of the gamma camera both inside and outside the MRI is 7.3% at 140 keV. The maximum increase in the integral uniformity was 3% when using a gradient echo MRI sequence while the mean differential uniformity when inside the MRI increased by 1%. Spatial resolution varied in a predictable manner from 2.4 mm FWHM at the collimator face to 6.9 mm at 10 cm from the collimator. Performance of the 3 T GE Discovery MR750 using a 16-channel breast RF coil array was measured with and without the gamma camera present using a gradient echo and spoiled gradient echo imaging sequence. A realistic 99mTc-filled breast-like phantom containing two lesions (30:1 lesion to background ratio) was used to assess the feasibility of both serial and simultaneous hybrid imaging. Sequential imaging resulted in a reduction in MRI SNR of 70-80% and a further decrease of 93-98% was observed when performing simultaneous MR/scintigraphy imaging, likely a result of RF interference originating from the CZT detector modules and associated analog electronics. Co-registered scintigraphic and MRI images display negligible geometric distortion when imaged with both simultaneous and serial imaging modes, thus indicating the feasibility of combining MBI with breast MRI.

Decoherence and relaxation of a single electron in a one-dimensional conductor

We study the decoherence and relaxation of a single elementary electronic excitation propagating in a one-dimensional chiral conductor. Using two-particle interferences in the electronic analog of the Hong-Ou-Mandel experiment, we analyze quantitatively the decoherence scenario of a single electron propagating along a quantum Hall edge channel at filling factor 2. The decoherence results from the emergence of collective neutral excitations induced by Coulomb interaction and leading, in one dimension, to the destruction of the elementary quasiparticle. This study establishes the relevance of electron quantum optics setups to provide stringent tests of strong interaction effects in one-dimensional conductors described by Luttinger liquids paradigm.

200 GHz Maximum Oscillation Frequency in CVD Graphene Radio Frequency Transistors.

Graphene is a promising candidate in analog electronics with projected operation frequency well into the terahertz range. In contrast to the intrinsic cutoff frequency (fT) of 427 GHz, the maximum oscillation frequency (fmax) of graphene device still remains at low level, which severely limits its application in radio frequency amplifiers. Here, we develop a novel transfer method for chemical vapor deposition graphene, which can prevent graphene from organic contamination during the fabrication process of the devices. Using a self-aligned gate deposition process, the graphene transistor with 60 nm gate length exhibits a record high fmax of 106 and 200 GHz before and after de-embedding, respectively. This work defines a unique pathway to large-scale fabrication of high-performance graphene transistors, and holds significant potential for future application of graphene-based devices in ultra high frequency circuits.

FPGA-Based I&C Systems in Nuclear Plants

The FPGA (field programmable gate array) is a digital device widely used in various fields of industry. FPGAs can be used to perform functions that are safety critical and require high reliability, like in automobiles, aircraft control and assistance and mission-critical applications in the aerospace industry. With these merits, FPGAs are receiving increased attention worldwide for application in nuclear plant instrumentation and control (I&C) systems, mainly for Reactor Protection System (RPS).Reasons for this include the fact that conventional analog electronics technologies are become obsolete. I&C systems of new Reactors have been designed to adopt the digital equipment such as PLC (Programmable Logic Controller) and DCS (Distributed Control System). But microprocessors-based systems may not be simply qualified because of its complex characteristics. For example, microprocessor cores execute one instruction at a time, and an operating system is needed to manage the execution of programs. As a result, nuclear power plant operators and I&C suppliers may consider other non-computer-based digital technologies, such as devices that may be configured using HDL (Hardware Description Language).FPGAs, commonly referred to as HDL programmable devices (HPDs), can run without an operating system and the design architecture is inherently parallel. Despite the attractive features, the use of such programmable devices in safety critical systems for nuclear power plants is relatively new in many countries, and the regulatory approach to licensing such devices may not be clear.In this paper we aim to assess advantages and the limitations on FPGA-based solutions, considering the design guidelines and regulations on the use of FPGAs in Nuclear Plant I&C Systems. We will also examine some circuit design techniques in FPGA to help mitigate failures and provide resilience. The objective is to show how FPGA-based systems can provide cost-effective options for I&C systems in modernization projects, ensuring safe and reliable operation, meeting licensing requirements, such as separation, redundancy and diversity.

New analog electronics for the new challenges in the synthesis of superheavy elements

A new series of experiments aimed at the synthesis and study of decay properties of the most neutron-deficient isotopes of element Fl (Z = 114) and of the heaviest isotopes of 118 element is planned at the DGFRS (FLNR JINR). An appropriate registering system is to be implemented to transfer spectrometric data from double-sided silicon strip detector (DSSD). New analog modules were designed that allow to simplify existing multi-channel measurement system and to improve the real-time method of “active correlations” in search for the rare events of SHE formation and decay. The main features of the new modules the 16-channel charge-sensitive preamplifier, the 16-channel analog multiplexer and the 1.25 MSPS 12-bit Parallel ADC are presented.

Heuristic for learning common emitter amplification with bipolar transistors

ABSTRACTMathematics in engineering education causes many thresholds in the courses because of the demand of abstract conceptualisation. Electronics depend heavily on more or less complex mathematics. Therefore the concepts of analogue electronics are hard to learn since a great deal of students struggle with the calculations and procedures needed. A survey was done focusing on students’ struggle to pass a course in analogue electronics by introducing a top-down perspective and the revised taxonomy of Bloom. From a top-down perspective you can create learning environments from any spot in the taxonomy using a step-by-step approach of the verbs understand and apply. Three textbooks with a top-down perspective on analogue electronics are analysed on the concept of amplifying with a transistor circuit. The study claims issues when losing the top-down perspective to present concepts and procedures of the content to be learned.