Analog Electronics Research Articles

Conditioning pain modulation reduces pain only during the first stimulation of thetemporal summation of pain paradigm in healthy participants.

Pro-nociceptive and anti-nociceptive mechanisms are commonly assessed in clinical and experimental pain studies, buttheir potential interaction is not well understood. Investigate the effect of conditioning pain modulation (CPM) on temporal summation of pain (TSP). Twenty healthy participants underwent cuff algometry assessment on the lower legs to establish the pressure pain tolerance threshold (PTT). For the TSP assessment, ten stimuli at the level of the PTT were delivered by computerised cuff inflations (1-s stimulation, 1-s break) while participants rated pain intensity on a 10-cm electronic visual analogue scale (VAS). This TSP paradigm was thenrepeated with a simultaneous conditioning stimulus induced by a cuff on the contralateral leg, inflated to a constant pressure corresponding to 30% (mild), 70% (moderate) or 100% (severe) of the PTT. These were assessed in a randomised order, with a fifteen-minute break between tests. A final TSP test without conditioning was reassessed at the end (post-recording). An interaction between stimuli (1-10) and repetition (p<0.05) was found for VAS scores. VAS scores for the first stimulus were decreased during 30%, 70%, and 100% conditioning intensities, compared to baselineand post-recordings (p<0.05). There was a significant increase in TSP during conditioning (p<0.05). There were no significant differences between baseline and post-recordings for any stimuli (p>0.05). The current study indicates that mild to severe stimuli administered by cuff algometry does not modulate summation effect of temporal summation of pain, which could indicate that pain facilitatory mechanisms are more potent compared with pain inhibitory mechanisms. Current knowledge on the interaction effect of pro and anti-nociceptive paradigms are the lacking. The current study indicates that conditioning pain modulation does not modulate thesummation effect of temporal summation of pain, when evaluated by computerized pressure algometry. This finding was independent of the mild, moderate and severe painful conditioning intensities.

Macroscopic Electron Quantum Coherence in a Solid-State Circuit

The quantum coherence of electronic quasiparticles underpins many of the emerging transport properties of conductors at small scales. Novel electronic implementations of quantum optics devices are now available with perspectives such as 'flying' qubit manipulations. However, electronic quantum interferences in conductors remained up to now limited to propagation paths shorter than $30\,\mu$m, independently of the material. Here we demonstrate strong electronic quantum interferences after a propagation along two $0.1\,$mm long pathways in a circuit. Interferences of visibility as high as $80\%$ and $40\%$ are observed on electronic analogues of the Mach-Zehnder interferometer of, respectively, $24\,\mu$m and $0.1\,$mm arm length, consistently corresponding to a $0.25\,$mm electronic phase coherence length. While such devices perform best in the integer quantum Hall regime at filling factor 2, the electronic interferences are restricted by the Coulomb interaction between copropagating edge channels. We overcome this limitation by closing the inner channel in micron-scale loops of frozen internal degrees of freedom, combined with a loop-closing strategy providing an essential isolation from the environment.

Assessing the Impact of Reflective Activities in Digital and Analog Electronics Courses

Contribution: This paper demonstrates positive outcomes from reflection-on-action by engineering students, including meaningful insights on their performance, professional and academic practices, and design knowledge as well as promising preliminary exam results. Background: Literature from the engineering education community underlines the benefits of reflection-based upon theories, such as Experiential Learning Theory, and calls for additional use of reflection in engineering education and associated scholarly work. Intended Outcomes: The authors intended for students to obtain meaningful academic and professional insights with implications for their future performance and to perform better on subsequent related exams via reflection. Application Design: Post-quiz and post-design reflective exercises were implemented in two electrical and computer engineering courses, Microelectronic Circuits and Advanced Digital Design, to drive student analysis of differences between their designs or calculations and the “standard solution” using simulation software and question prompts. Reflection-on-action was chosen to enhance students’ post-activity understanding and insight, as ultimate learning requires reflection whereby students identify errors and strategies for improvement. Findings: Results demonstrated the value of reflection-on-action using post-activity comparisons and simulation. The students’ reflective content and interviews demonstrated substantial professional and academic insights from and appreciation for reflection. On the Microelectronics final exam, a medium effect was associated with the reflection, and for the Digital Design exam, the effect was small to medium. Differences in depth levels of the students’ reflections associated with the two types of problems (quiz questions versus design) were evident, suggesting problem type may impact depth.

Automating the Design of Asynchronous Logic Control for AMS Electronics

Analog and mixed signal (AMS) electronics becomes increasingly complex and needs to be digitally enhanced by its own control circuitry. The RTL synthesis flow routinely used for digital logic is, however, optimized for synchronous data processing and produces inefficient control for AMS. In this paper, we demonstrate the evident benefits of asynchronous circuits in the context of AMS systems, and propose an asynchronous design for analog electronics (A4A) flow for their specification, synthesis, and formal verification. A library of specialized analog-to-asynchronous (A2A) components is developed for interfacing analog and asynchronous worlds. A4A flow is automated in the Workcraft framework and evaluated using a multiphase buck converter case study, where A2A components are employed to sanitize analog sensor readings. Timing analysis of asynchronous buck control shows improved response time: 4× reaction to high-load and 7× to under-voltage condition, compared with a 333 MHz clocked controller (to achieve a similar response time, a clocked controller would require ~3 GHz frequency). The simulation results of a 4-phase asynchronous buck demonstrate improved voltage ripple and peak current -16% and 12% reduction, respectively. These benefits lead to the higher efficiency of power conversion, and can be traded off for the cost of analog components, e.g., coils. Moreover, the use of the proposed design flow and tools helps to improve design productivity and overall robustness of AMS circuits.

Культура сприймання та аналізу медіатекстів популярних видань медичної тематики

Nowadays, in society, an increase in the volume of information and unrestricted access to it requires an adequate level of information perception culture, hence the education of a competent media consumer, the formation of his personal media culture. The question of the formation of individual media culture among the readers of the medical press is not sufficiently highlighted in the scientific and methodological literature, which predetermined the choice of the topic of research.The article analyzes the concept of media culture in the information society and its interrelation with the general, informational and communicative culture. The components of media culture are defined — media awareness and media literacy. The composition of popular newspapers and medical magazines of 2019 are considered, the classification characteristics for their division.The purpose of the article is to determine the essence, specificity of the culture of perceiving media texts of popular medical issues, and to characterize such publications. The study of the culture of media perception of periodicals on medical topics deepens and clarifies the theory of social communications, provides practical material for theoretical generalizations.The publications are analyzed in the presence of different formats — only printed editions or printed editions and their electronic analogues. Great value and demand among readers have platforms where you can quickly exchange information, receive answers to questions, expert advice.On the subject are singled out one-level and various-mathematical publications. According to the linguistic feature, only Ukrainian-language publications and those published in several languages (Russian, English and German), or only in Russian, are highlighted. The thematic content of the publications is determined, it is accentuated on their cognitive and educational functions.The types of media consumers are indicated by the level of perception of information and the development of media culture. The stages of perceiving media texts of the non-specialized press on medical topics are generalized and systematized.The motivation for the consumption of media products is described. Problems in media perception are encountered by readers of popular medical issues. It is noted that the result of conscious perception of the content and form of media texts is changes in the outlook of media consumers, their emotions and behavior. It is about development: self-knowledge, self-education, self-education of media consumers in order to regulate their own health; communicative abilities, realized in the creation of their own media text; creative expression.The problems of information culture in popular editions of medical subjects (inaccurate interpretation of certain problems, representation of hypotheses as established facts, manipulation of the consciousness of readers), which adversely affect the media perception of readers are revealed.

Ionic Coulomb blockade as a fractional Wien effect.

Recent advances in nanofluidics have allowed the exploration of ion transport down to molecular-scale confinement, yet artificial porins are still far from reaching the advanced functionalities of biological ion machinery. Achieving single ion transport that is tunable by an external gate-the ionic analogue of electronic Coulomb blockade-would open new avenues in this quest. However, an understanding of ionic Coulomb blockade beyond the electronic analogy is still lacking. Here, we show that the many-body dynamics of ions in a charged nanochannel result in quantized and strongly nonlinear ionic transport, in full agreement with molecular simulations. We find that ionic Coulomb blockade occurs when, upon sufficient confinement, oppositely charged ions form 'Bjerrum pairs', and the conduction proceeds through a mechanism reminiscent of Onsager's Wien effect. Our findings open the way to novel nanofluidic functionalities, such as an ion pump based on ionic Coulomb blockade, inspired by its electronic counterpart.

Surfacing learner intuitions about electrical circuit design using an open-source virtual environment ‘chart-a-path’

Engaging and understanding student-thinking in electrical circuit design can be challenging. While the analysis of circuits is an important component of an Analog Electronics course, one of the primary areas of difficulty faced by students is that they do not have a clear understanding of the current flow. Attempts at mediating this gap are usually limited to the use of metaphors and (too) much is left to the learners’ imagination. This paper reports an intervention co-designed with a lecturer with regard to an undergraduate module on Analog Electronics. The intervention was an open-source immersive virtual environment designed to afford representations of learner intuitions in electrical circuit design with a view to helping their tutor have a better understanding of the roots of their misconceptions. The paper highlights some of the benefits and challenges of using immersive environments and the design and development process, as well as the collaborative learning that resulted.

Multifunctional quantum thermal device utilizing three qubits.

Quantum thermal devices which can manage heat as their electronic analogs for the electronic currents have attracted increasing attention. Here a three-terminal quantum thermal device is designed by three coupling qubits interacting with three heat baths with different temperatures. Based on the steady-state behavior solved from the dynamics of this system, it is demonstrated that such a device integrates multiple interesting thermodynamic functions. It can serve as a heat current transistor to use the weak heat current at one terminal to effectively amplify the currents through the other two terminals, to continuously modulate them ranging in a large amplitude, and even to switch on or off the heat currents. It is also found that the three currents are not sensitive to the fluctuation of the temperature at the low-temperature terminal, so it can behave as a thermal stabilizer. In addition, we can utilize one terminal temperature to ideally turn off the heat current at any one terminal and to allow the heat currents through the other two terminals, so it can be used as a thermal valve. Finally, we illustrate that this thermal device can control the heat currents to flow unidirectionally, so it has the function of a thermal rectifier.

Book Reviews [7 Books reviewed

The following 7 books were reviewed: Interval Finite Element Method with MATLAB;S . Nayak and S. Chakraverty; Measurements and Analysis of Overvoltages in Power Systems; J. Li; Power Microelectronics - Device and Process Technologies, 2nd Edition; Y. C. Liang, G. S. Samudra, and C. Huang; Advanced DC/DC Converters, 2nd Edition; F. L. Luo and H. Ye; Analog Electronics for Measuring Systems; D. Bucci; Astrochemistry - Big Bang to the Present Day; C. Vallance; Concepts in Physical Metallurgy; A. Lavakumar.

Development of Analog-Based Online Electronic Learning Models in Improving Students Learning Outcomes in Informatics Engineering Study Programs

This study aims at developing an online based learning model in analogue electronics subjects. Respondents in this study were limited to students at STMIK Dipanegara Makassar who took analogue electronics courses. The research method used was research and development method which referred to Borg &amp; Gall, Dick and Carry and Hannafin and Peck Models. To see the feasibility of the model that has been developed, researchers conducted expert tests, 1-1 tests, small group tests, and field trials in which the indicator is student learning outcomes of informatics engineering study programs. The results of this study indicate that this model is a potential design that is effective to be used during learning. It is proven by the increase of the completeness value of learning outcomes reached by the students. The average score of the learning outcome is 79.05 after using the learning model. The average score before using this learning model is only 55.05. Therefore, it can be concluded that the model developed has been effective in improving student learning outcomes in analogue electronics courses.

Realization of Diverse Waveform Converters from a Single Nanoscale Lateral p-n Junction Cu2S-CdS Heterostructure.

A differentiator is an electronic component used to accomplish mathematical operations of calculus functions of differentiation for shaping different waveforms. Differentiators are used in numerous areas of electronics, including electronic analog computers, wave-shaping circuits, and frequency modulators. Conventional differentiators are fabricated using active operational amplifiers or using passive resistor-capacitor combinations. Here, we report that a single Cu2S-CdS heterostructure acts as a differentiator for performing numerical functions of input waveform conversion into different shapes. When a rectangular wave signal is applied through the tip of a conductive atomic force microscope, a spikelike wave signal is obtained from the Cu2S-CdS heterostructure. The Cu2S-CdS differentiator is able to convert a sine wave signal into a cosine wave signal and a triangular wave signal into a square wave signal similar to the classical differentiators. The finding of ananoscale differentiator at extremely small length scales may have profound applications in different domains of electronics.

Sodium Intake Beliefs, Information Sources, and Intended Practices of Endurance Athletes Before and During Exercise.

There is little information describing how endurance athletes perceive sodium intake in relation to training and competition. Using an online questionnaire, this study assessed the beliefs, information sources, and intended practices regarding sodium ingestion for training and competition. Endurance athletes (n = 344) from six English-speaking countries completed the questionnaire and were included for analysis. The most cited information sources were social supports (63%), self-experimentation (56%), and media (48%). Respondents generally believed (>50% on electronic visual analog scale) endurance athletes require additional sodium on a daily basis (median 67% [interquartile range: 40-81%]), benefit from increased sodium in the days preceding competition (60% [30-77%]), should replace sodium losses during training (69% [48-83%]) and competition (74% [54-87%]), and would benefit from sweat composition testing (82% [65-95%]). Respondents generally believed sodium ingestion during endurance exercise prevents exercise-associated muscle cramps (75% [60-88%]) and exercise-associated hyponatremia (74% [62-89%]). The majority (58%) planned to consciously increase sodium or total food intake (i.e.,indirectly increasing sodium intake) in the days preceding competition. Most (79%) were conscious of sodium intake during competition, but only 29% could articulate a specific intake plan. A small minority (5%) reported using commercial sweat testing services, of which 75% believed it was beneficial. We conclude that endurance athletes commonly perceive sodium intake as important for their sporting activities. Many intend to consciously increase sodium intake in the days preceding and during competition, although these views appear informed mostly by nonscientific and/or non-evidence-based sources.

Boron-based inorganic heterocyclic clusters: electronic structure, chemical bonding, aromaticity, and analogy to hydrocarbons.

This Perspective article deals with recent computational and experimental findings in boron-based heterocyclic clusters, which focuses on binary B-O and B-S clusters, as well as relevant ternary B-X-H (X = O, S, N) species. Boron is electron-deficient and boron clusters do not form monocyclic rings or linear chains. Boron-based heterocyclic clusters are intuitively even more electron-deficient and feature exotic chemical bonding, which make use of O 2p, S 3p, or N 2p lone-pairs for π delocalization over heterocyclic rings, facilitating new cluster structures and new types of bonding. Rhombic, pentagonal, hexagonal, and polycyclic clusters are discussed herein. Rhombic species are stabilized by four-center four-electron (4c-4e) π bonding, that is, the o-bond. An o-bond cluster differs from a typical 4π antiaromatic system, because it has 4π electrons in an unusual bonding/nonbonding combination, which takes advantage of the empty 2pz atomic orbitals from electron-deficient boron centers. A variety of examples (notably including boronyl boroxine) possess a hexagonal ring, as well as magic 6π electron-counting, making them new members of the inorganic benzene family. Pentagonal clusters bridge rhombic o-bond systems and inorganic benzenes, but they do not necessarily favor 6π electron-counting as in cyclopentadienide anion. In contrast, pentagonal 4π clusters are stable, leading to the concept of pentagonal o-bond. One electron can overturn the potential energy landscape of a system, enabling rhombic-to-hexagonal structural transition, which further reinforces the idea that 4π electron-counting is favorable for rhombic systems and 6π is magic for hexagonal rings. The bonding analogy between heterocyclic clusters and hydrocarbons goes beyond monocyclic species, which allows rational design of boron-based inorganic analogs of polycyclic aromatic hydrocarbons, including s-indacene as a puzzling aromatic/antiaromatic system. Selected linear B-O clusters are also briefly discussed, featuring dual 3c-4e π bonds, that is, ω-hyperbonds. Dual ω-hyperbonds, rhombic or pentagonal o-bond, and inorganic benzenes share a common chemical origin. The field of boron-based heterocyclic clusters is still in its infant stage, and much new chemistry remains to be discovered in forthcoming experimental and theoretical studies.

INNOVATIVE WAYS OF THE DEVELOPMENT OF THE SCIENTIFIC PERIODICAL EDITION OF THE ECONOMIC PROFILE

The weak competitiveness of domestic science is one of the painful realities of the present. Experts in the field of science-research studies note the low publishing activity of Ukrainian scientists and the lack of knowledge of foreign colleagues in the results of domestic scientists. All this leads to insufficient integration of Ukrainian science into the world scientific community and complicates the cooperation of our scientists in the field of global scientific projects. One of the ways to intensify interaction with the international scientific community is to create competitive professional editions, with high-quality content, published in several languages and having analogies on the Internet. The article summarizes the experience of development of domestic scientific editions of the economic profile (EEP). The purpose of the publication of this work is to describe the internal and external environment of the innovative project of the site of the scientific national journal of the economic profile, namely the substantiation of the project of the electronic version of such edition (EVE). The influence of macroeconomic factors has been investigated. It has been shown that legal and technological factors affect the development of the publication and its electronic analogue positively, and the social, economic and political factors affect the project rather contradictory. The competitive advantages of a modern national economic journal are formulated, such as the availability of an electronic version of the magazine with support for multimedia, access to full-text archives, as well as a well-considered editorial policy and a stable reviewing system. The priority areas for the development of the EEP are the improvement of the quality of scientific publications and a registration of the journal in the science and technology databases of Web of Science and SCOPUS, which presupposes compliance with such requirements as, ISSN availability, periodicity of release, a stable review system, a well-considered editorial policy, a statement of compliance with publication ethics, wide enough geography of authors, presence of a site of a scientific journal (EVE), high quality of polygraphy.

Complex Dynamics of the Chua’s Circuit System with Adjustable Symmetry and Nonlinearity: Multistability and Simple Circuit Realization

Background: Since the invention of Chua’s circuit, numerous generalizations based on substitution of the nonlinear function have been reported. One of the generalizations is obtained by replacing the piecewise-linear with the cubic and/or quadratic polynomial. These nonlinearities are used to be implement using analog multipliers which are relatively expensive. In this realization we propose a different approach to synthetize both cubic and quadratic nonlinearities of empirical Chua’s circuit. Methods: The idea is to use diodes, Opamps and resistors to derive a PWL approximation of the cubic and quadratic functions. To demonstrate some complex phenomena observed in the system using the fourth order Runge-Kutta numerical integration method with a very small integration step. The bifurcation diagram which is the plot of local maxima of the temporal trace of a system’s coordinate as a function of the control parameter also constitutes an excellent tool for the study of dynamic systems. Results: The above mentioned standard nonlinear analysis tools have been exploited and it is found that the system with adjustable symmetry experiences a plethora of symmetric and asymmetric coexisting attractors. A particular feature of the system is related to the simplicity of the corresponding electronic analog circuit (no analog multiplier chip used to implement the cubic and quadratic nonlinearities). Conclusions: It is observed that the proposed Chua’s circuit system is more flexible (both symmetric and asymmetric) and displays complex dynamics behaviors of symmetric and asymmetric coexisting attractors. Note that this striking dynamic can be exploited in encryption algorithms.

Neural Spike Digital Detector on FPGA

This paper presents a multidisciplinary experiment where a population of neurons, dissociated from rat hippocampi, has been cultivated over a CMOS-based micro-electrode array (MEA) and its electrical activity has been detected and mapped by an advanced spike-sorting algorithm implemented on FPGA. MEAs are characterized by low signal-to-noise ratios caused by both the contactless sensing of weak extracellular voltages and the high noise power coming from cells and analog electronics signal processing. This low SNR forces to utilize advanced noise rejection algorithms to separate relevant neural activity from noise, which are usually implemented via software/off-line. However, off-line detection of neural spikes cannot be obviously used for real-time electrical stimulation. In this scenario, this paper presents a proper FPGA-based system capable to detect in real-time neural spikes from background noise. The output signals of the proposed system provide real-time spatial and temporal information about the culture electrical activity and the noise power distribution with a minimum latency of 165 ns. The output bit-stream can be further utilized to detect synchronous activity within the neural network.

Incorporating the 21st Century Skills in The Development of Learning Media for Analog Electronics II Practicum

This was a Research and Development study aimed to develop practical learning media in the forms of a trainer and a module for Electronics Engineering Education students in Analog Electronics II Practicum course. The R&D model applied in this study consisted of four phases: assessment/analysis, design, development, and evaluation. The trainer as an object media consisted of: 1) a circuit blok, including (a) a voltage feedback, (b) a phase-shift oscillator, (c) a regulated power supply, and (d) a wien-bridge oscillator; 2) a reverse engineering block; 3) a project board block; and 4) a power block. Meanwhile, the text media were modules containing both the materials and the jobsheets about the practicum manual, and consisting of specific sub-chapters on how to develop the 4Cs of the 21st century skills. The trainer performance showed that all blocks in this media were functioning properly. The feasibility of this media was rated 3.3 (highly feasible), 2.97 (feasible), and 3.3 (highly feasible) by the media experts, the material experts, and the users respectively. These results indicated that the trainer was ready to be used in helping the students to understand the materials and to develop the 21st century skills, namely critical thinking and problem solving, creativity, communication, and collaboration.

Antimonotonicity, chaos, quasi-periodicity and coexistence of hidden attractors in a new simple 4-D chaotic system with hyperbolic cosine nonlinearity

Recently, the study of systems with hidden attractors has become one of the most followed topics owing to their fundamental and technological importance. This contribution is focused on a new simple 4-D chaotic system (whose nonlinearity is a hyperbolic function) inspired by the quadratic system introduced by [Jay and Roy Nonlinear Dyn (2017) 89:1845–1862]. Basic properties of the new system are discussed and its complex behaviors are characterized using dynamic systems analysis tools. This system exhibits a rich repertoire of dynamic behaviors including chaos, chaos 2-torus, and quasi-periodic. Other interesting phenomena such as multistability, antimonotonicity, and torus-doubling bifurcations are also reported. Moreover, the hyperbolic cosine nonlinearity is easily implemented by using a pair of semiconductor diodes (no analog multiplier is involved). We confirm the feasibility of the proposed theoretical model using PSpice simulations and a physical realization based on an electronic analog implementation of the model.

Transient Variability in SOI-Based LIF Neuron and Impact on Unsupervised Learning

Variability is an integral part of biology. A biological neural network performs efficiently despite variability and sometimes its performance is facilitated by the variability. Hence, the study of variability on its electronic analog is essential for constructing biomimetic neural networks. We have recently demonstrated a compact leaky integrate and fire (LIF) neuron on PD-silicon on insulator (SOI) MOSFET. In this paper, we have studied impact ionization (II)-induced variability both device-to-device (D2D) and cycle-to-cycle (C2C) in the SOI neuron. The C2C variability is attributed to the fluctuation in the II-generated charge storage and it is enhanced by at least $2.5\times $ as compared to the no-II case. The D2D variability, on the other hand, is related to the II-induced sharp subthreshold slope (~40 mV/decade), which enhanced the variability by $\sim 20\times $ compared to the no-II case. The impact of the enhanced variability in SOI neurons on an unsupervised classification task was evaluated by simulating a spiking neural network (SNN) with both analog and binary synapses. For analog synapse-based SNN, the C2C variability improved the performance by ~5% relative to ideal LIF neurons. However, the D2D variability, as well as combined D2D and C2C variability, degrades learning by −~10%. For binary synapses, we observe that performance drastically degrades for ideal LIF neurons as the synaptic weight initialization becomes nonrandom. However, neurons with the experimentally demonstrated variability (C2C and D2D) mitigate this challenge. Therefore, this enables binary synapses to perform at par with analog synapses, which allows for deterministic weight initialization. This makes RNG circuits for random weight initialization redundant.

Electronic excitation of atoms by positron impact using the scaling Born approach

We consider the efficacy of the scaling Born positron (SBP) approach, in calculating reliable integral cross sections (ICS) for positron impact excitation of electronic states in atoms. We will demonstrate, using specific examples as H, He, Hg, and Mg, that this relatively simple procedure can generate quite accurate ICS when compared with more sophisticated methods. In the absence of the experimental data, comparisons are made with analogous electron scattering.