Resistive Electrical Circuits Research Articles

Generalized utilization of energy harvesting ability of TENG for concurrent energy storage and motion sensing application with effective external circuitry

Utilizing triboelectric nanogenerators (TENGs) for simultaneous mechanical energy harvesting and sensing applications is a crucial and challenging endeavor that can improve TENG-based self-powered sensing systems. However, this issue remains relatively underexplored and thus, it is the primary focus here. We propose a simple and generalizable external circuitry achieving simultaneous energy storage and sensing from the TENGs. Commonly available polydimethylsiloxane (PDMS) triboelectric film is dielectrically modified by loading synthesized sodium tantalate filler particles with high dielectricity. The fabricated films and aluminum tape are utilized as negative and positive triboelectric films. The electrical performance of the TENG operated in contact-separation mode is optimized based on the filler concentration in the PDMS film and the maximum electrical output of ∼ 195 V, ∼ 6.27 µA, and ∼ 44 µC/m2 is observed. Completely analyzed TENG with highly efficient and stable electrical output (for more than 10,000 operational cycles) is utilized for further experiments. Various fundamental voltage divider (VD) (capacitive, resistive, and inductive) electrical circuits are fabricated and their successful utilization for dividing the electrical output from the TENG is demonstrated. After a comprehensive analysis of the compatibility between the VD and TENG, it is determined that inductive and resistive VDs are the optimal choice. Owing to its simplicity, the resistive VD is further utilized to construct real-time vehicle speed sensing and approaching direction-finding applications. The proposed simple and generalized state-of-the-art process for simultaneous energy storage and sensing through the TENG could be revolutionary, potentially expanding its applicative scope significantly.

Frequency Propagation: Multimechanism Learning in Nonlinear Physical Networks.

We introduce frequency propagation, a learning algorithm for nonlinear physical networks. In a resistive electrical circuit with variable resistors, an activation current is applied at a set of input nodes at one frequency and an error current is applied at a set of output nodes at another frequency. The voltage response of the circuit to these boundary currents is the superposition of an activation signal and an error signal whose coefficients can be read in different frequencies of the frequency domain. Each conductance is updated proportionally to the product of the two coefficients. The learning rule is local and proved to perform gradient descent on a loss function. We argue that frequency propagation is an instance of a multimechanism learning strategy for physical networks, be it resistive, elastic, or flow networks. Multimechanism learning strategies incorporate at least two physical quantities, potentially governed by independent physical mechanisms, to act as activation and error signals in the training process. Locally available information about these two signals is then used to update the trainable parameters to perform gradient descent. We demonstrate how earlier work implementing learning via chemical signaling in flow networks (Anisetti, Scellier, etal., 2023) also falls under the rubric of multimechanism learning.

A Review of Piezoelectric Footwear Energy Harvesters: Principles, Methods, and Applications.

Over the last couple of decades, numerous piezoelectric footwear energy harvesters (PFEHs) have been reported in the literature. This paper reviews the principles, methods, and applications of PFEH technologies. First, the popular piezoelectric materials used and their properties for PEEHs are summarized. Then, the force interaction with the ground and dynamic energy distribution on the footprint as well as accelerations are analyzed and summarized to provide the baseline, constraints, potential, and limitations for PFEH design. Furthermore, the energy flow from human walking to the usable energy by the PFEHs and the methods to improve the energy conversion efficiency are presented. The energy flow is divided into four processing steps: (i) how to capture mechanical energy into a deformed footwear, (ii) how to transfer the elastic energy from a deformed shoes into piezoelectric material, (iii) how to convert elastic deformation energy of piezoelectric materials to electrical energy in the piezoelectric structure, and (iv) how to deliver the generated electric energy in piezoelectric structure to external resistive loads or electrical circuits. Moreover, the major PFEH structures and working mechanisms on how the PFEHs capture mechanical energy and convert to electrical energy from human walking are summarized. Those piezoelectric structures for capturing mechanical energy from human walking are also reviewed and classified into four categories: flat plate, curved, cantilever, and flextensional structures. The fundamentals of piezoelectric energy harvesters, the configurations and mechanisms of the PFEHs, as well as the generated power, etc., are discussed and compared. The advantages and disadvantages of typical PFEHs are addressed. The power outputs of PFEHs vary in ranging from nanowatts to tens of milliwatts. Finally, applications and future perspectives are summarized and discussed.

The Use of Concept Cartoons in Overcoming The Misconception in Electricity Concepts

Electricity is a very important concept in learning Physics. Mastering this concept can make learning Physics meaningful and relatable to real life problems. However, literature indicates that students have poor conceptual understanding of concepts about electricity. The current research aims to improve Form 5 (aged 17 years) students’ understanding of direct current circuits by using Concept Cartoons Worksheets. Concept Cartoons are A single-group pre-test/post-test investigation was carried out using seven Concept Cartoons Worksheets designed to address common conceptual misconceptions about direct current circuits with a total of 30 physics student participants. The seven Concept Cartoons were modified based on the Concept Inventory Test “Determining and Interpreting Resistive Electric Circuit Concepts Test (DIRECT). Concept Cartoons Worksheets were used to correct students’ misconceptions about direct current circuits and to increase their level of conceptual understanding. The data collected were analysed quantitatively to obtain percentages, means, and t-test values. The descriptive statistics showed an increase in the level of student’s conceptual understanding after the use of Concept Cartoons. The t-test analysis reported that the difference was significant. The results show that Malaysian students do have misconceptions about electricity concepts. However, Concept Cartoons Worksheets are effective to overcome students’ misconceptions about electrical concepts, specifically toward current circuits. Concept Cartoons are not only effective in overcoming misconceptions among students, they are also refreshing and unique because of the cartoons presented while relating to Physics concepts that are abstract.

First-year university students' conceptual understanding of electric circuits in relation to school and personal background

This paper reports a quantitative study about university students’ conceptual understanding of simple DC-circuits when entering firstyear physics at a South African university. The aim was to investigate how conceptual understanding relates to the students’ personal and school background. The conceptual framework was based on an existing model of the effectiveness of science education. Data were collected from 815 participants at a South African university. The conceptual understanding of DC circuits was measured in terms of performance in the well-known Determining and Interpreting Resistive Electric Circuits Concepts Test (DIRECT). Background information at school, classroom, and personal level was obtained with a questionnaire. Using Rash analysis, it was found that the students’ conceptual understanding relates significantly to the type of school attended, home language, previous achievement, their attitudes towards physics, and gender. However, contrary to expectations, the students’ conceptual understanding did not show a relationship with their exposure to practical work at school.

Анализ электровзрывобезопасности на основе динамических моделей разряда при коммутации электрической цепи

A mathematical model describing a switching arc discharge in an RL electric circuit based on the Mayr equation is developed and tested. The body of mathematics representing an arc discharge appearing in an RL circuit that takes into account the dynamic current-voltage arc characteristic and arc thermal processes is described. The results from calculating the arc thermal inertia constant for the switching period for a resistive circuit by several known methods, including the values obtained during simulation, are given. It has been found that the arc discharge model that takes into account the arc thermal inertia constant dynamics calculated from the instantaneous values of the average discharge power (taking the cathode losses into account) gives better convergence of the simulation results. An improved mathematical model of discharge in resistive and inductive electrical circuits is proposed, which makes it possible to refine the well-known method for quantifying their intrinsic safety. The convergence with the minimal igniting parameters obtained experimentally for similar circuits is analyzed.

Physics Students’ Conceptual Understanding of Electricity and Magnetism in Nine Years Basic Education in Rwanda

<p style="text-align: justify;">We investigate students’ misconceptions in electrostatics, direct current (DC) and magnetism which are important in electricity and magnetism. We developed and administered a multiple-choice questionnaire test to reveal students’ misconceptions related to charged bodies, lightning, electric fields, electric potential, forces, DC resistive electric circuits and magnets. This test aimed at obtaining quantitative information about misconceptions and was administered to 380 senior two students from Nine Year Basic Education (9YBE) Schools. The selected students have some experience with the new Rwandan secondary physics Competence Based Curriculum (CBC) that is currently under implementation. We find that senior two students have several common misconceptions related to these concepts. The data indicate that although students have some backgrounds on the subject matter, they still seem to believe that if the two charges are separated by a distance, a large-charged object exerts a greater force of attraction or repulsion on the small one. Considerable number of participated students held the misconception of considering current consumption in the resistor/bulb or the electrical devices in the circuits. They also believed that the battery was a continuous current source. The findings also revealed that students held a misconception that a bar magnet when broken into pieces, it is demagnetized. Moreover, a considerable number of participants hold the misconception that all metals are attracted by a magnet. Our study also revealed some of the statistically significant differences in terms of either gender or location of schools for some items.</p>

Control of damping of structural vibrations by using different mechanisms of energy dissipation

In current paper an influence of adding piezoelectric elements and connection of their electrodes to external resistive electric circuits on coefficients of vibration damping of piecewise-homogeneous viscoelastic structures was demonstrated on the example of a cantilever plate. The calculations were carried for two options of location of piezoelectric elements in relation to the plate (in the middle of the plate and nearby the clamped edge) and two options of mutual arrangement of a piezoelectric element and a viscoelastic layer (at one side of the plate and at opposite sides). One was demonstrated that damping coefficients for the first two the most energy-intensive vibration modes can be increased in different degree by using different mechanisms of energy dissipation. In this case the most preferable configuration for reaching the highest value of vibration damping coefficients is the option when piezoelectric element and viscoelastic layer located at opposite sides of the plate.

“Knowledge in Pieces” View: Conceptual Understanding Analysis of Pre-service Physics Teachers on Direct Current Resistive Electrical Circuits

In agreement with problem-solving skills, identifying conceptual understanding is an important topic in physics. The purpose of this study was to analyze the conceptual understanding of physics teacher prospective students on direct current based electric material “Knowledge in Piece” Theory. The study used a mixed-method approach with an explanatory model with 148 Physics Pre-service at the Jambi University, Indonesia. Data were collected using tests and interviews. The students were given a test using reasoned multiplechoice question developed to find out the understanding of student concepts, while unstructured interviews were conducted to confirm student answers that were not clear.Data analysis was done by using a rubric which as developed based on the possible reasons for student’ answer to the concept of direct current electricity. The result of study showed that understanding the concept of students in direct current electricity material is still not very good, this is shown from the study data only 6 people (4%) of 148 students who can activate the concept well and completely. The findings show that student understanding is still in the form of concept pieces. Students are not able to connect concepts properly. When asked about sub-material students have an understanding, but when the problem is given is complete enough students are not able to connect every concept to the sub-material that they understand correctly. These results give strength that the students' understanding had not been coupled coherently so that the less dominant resource would be delayed to activate than the more dominant resource.

A comparative analysis of two approaches to damping of vibrations

In the current paper a comparison between two approaches to damping of vibrations is presented. A comparative analysis was carried-out on the example of a cantilever plate. In the first case, the surface of the plate was covered with a layer of viscoelastic material. Its mechanical behavior is described by equations of the linear theory of viscoelasticity based on complex dynamic moduli. In this case, the complex dynamic moduli can increase or decrease as the oscillation frequency increases, or remain constant. It is assumed that the thickness of the viscoelastic layer is equal to the thickness of the plate.In the second case piezoelectric elements shunted with resistive (R) or resonant (RL) electric circuits were applied for damping of vibrations. In this case, for each vibration mode, the optimal location of the piezoelectric element and the parameters of the external electrical circuit are determined. The comparison is carried out on the basis of analysis of the vibration damping coefficients determined by the value of the complex natural vibration frequencies obtained from the solution to the problem of natural vibrations for electro-viscoelastic bodies with external electric circuits. Numerical implementation was performed using finite element method.

Play dough circuits: a tangible and friendly medium for understanding physics

Students consider that physics is difficult because of its abstract nature and the involvement of mathematics. One of the most difficult topics is a simple direct current circuit. Physics education research shows that students learn better when they construct their own understanding of scientific ideas within the framework of their existing knowledge. To accomplish this process, students must be motivated to engage with the content actively and be able to learn from that engagement. The purpose of this research was to compare the grade 6 students’ understanding of the scientific concept of simple direct circuits before and after participating in a STEM activity that involved the building of circuits from play dough. Twenty questions from the Interpreting Resistive Electric Circuit Concepts Test were selected to evaluate students’ reasoning regarding direct current resistive electric circuits. Findings revealed that the students’ scores working with the different conditions after learning were significantly higher than they were before learning. However, analysis on learning progress showed that the group that had to create more works had higher normalized gain than the group that created less works. When the work was analysed with rubric criteria, it illustrated that more conditions caused more complexity and diversity to the work. In short, the condition or situation set to students affected work creation.

Harmonic analysis and experimental validation of bistable vibration energy harvesters interfaced with rectifying electrical circuits

The high-performing, nonlinear vibration energy harvesters are conventionally investigated when integrated with simplified resistive electrical circuits (AC circuits), while in fact DC voltages are needed for electronics and rechargeable batteries in practical applications. To lead to an accurate and effective set of design guidelines for realistic energy harvesting system development, an analytical, harmonic balance based method is proposed to characterize the steady state performance and investigate the DC circuit effects. During the route of the analysis method, the induced nonlinear, piecewise piezovoltage is firstly approximated via smooth dynamic responses based on the energy equivalence, which enables the followed harmonic balance operation to analytically estimate the vibration amplitude. The parameter studies show the pros and cons of the coupling constant and resistive load. In one side, with increasing the coupling constant or load resistance during their moderate range, higher electric power is extracted. In the other side, higher piezoelectric coupling and resistive load compromise the beneficial bandwidth of snap-through vibrations. Moreover, comparisons are conducted to reveal the different structural roles of the standard electrical circuit and AC circuit. It is found that AC circuit exhibits equivalent damping effect while the standard rectifying electrical circuit exhibits both equivalent damping and stiffness effects to the harvester system. These different circuit effects explain the theoretically predicted and numerically validated phenomena that the standard rectifying electrical circuit extracts less electric power than AC circuit under moderate piezoelectric coupling constants and resistive loads, while outperforms AC circuit when the coupling constants or load resistances are relatively large.

Higher Dimensional Electrical Circuits

In this paper, we describe a physical problem, based on electromagnetic fields, whose topological constraints are two-dimensional versions of Kirchhoff’s laws, involving 2-simplicial complexes embedded in $${\mathfrak {R}}^3$$ rather than graphs. The topological constraints are on flux and mmf vectors, which we show satisfy a ‘generalized Tellegen’s Theorem,’ i.e., that they constitute complementary orthogonal vector spaces analogous to voltage and current spaces for ordinary graph-based electrical circuits. We show that the problem of solving this two-dimensional electrical circuit reduces to that of solving an ordinary resistive electrical circuit that can be regarded as dual to it. We present a linear time algorithm for constructing, the above mentioned, dual electrical network. This algorithm is based on the construction of a triangle adjacency graph of the original embedded 2-simplicial complex. This graph contains the information of the order in which we encounter the triangles incident at an edge, when we rotate say clockwise with respect to the orientation of the edge. The triangle adjacency graph is processed through a ‘sliding’ algorithm which simulates sliding on the surfaces of the triangles, moving from one triangle to another which shares an edge with it but which also is adjacent with respect to the embedding of the complex in $${\mathfrak {R}}^3$$. The connectedness information provided by this algorithm is used to construct, in linear time on the size of the 2-simplicial complex, its dual graph.

Analysis of Engineering Students’ Common difficulties with DC electric circuits in an Inquiry-based laboratory

The students’ understanding about direct current electric circuits’ concepts has been extensively investigated in secondary schools as well as at university level. In the University of São Paulo (IFSC/USP), for more than 10 years, our group has been researching the Electricity and Magnetism laboratory course to Engineering students’. Similarly to reported in the literature, we observed that students often leave physics classes with less of an understanding of physics concepts than we had expected. In this paper we present an investigation of the difficulties that students in the Electricity and Magnetism laboratory have with current electric circuits' concepts and how that research was used as a guide in the development and evaluation of the guided-inquiry lab on these topics to help students learn these concepts better. Initially, we adapted a question developed by McDermott in 2006 and employed it to investigate students’ conceptual understanding of electric circuits in three states of Brazil. STEM areas were involved in this research and the question was applied after students attended to theoretical and laboratory courses. Students had to order light bulbs according to brightness in three different electric circuits to answer the question. Only ~13% of students answered correctly agree to result in other countries and it inspired us to restructure the laboratory guide from a course in our institution. Our new guide was inquiry-based with some activities adapted from Tutorials in Introductory Physics and others developed in a prediction-observation-explanation form. The same question was used as pre and post-test and the average percentage of students who got the maximum score was 47%. We also have been using the Determining and Interpreting Resistive Electric Circuit Concepts Test (DIRECT), which is composed by a 29-multiple choice questions, that can be grouped in conceptual objectives, allowing us identifying specific conceptual difficulties. We proposed many modifications in the students’ guide, after analyzing the questions, and some of them we managed to improve, like those related to resistance and current. On the other hand, less than 50% of students could answer correctly some questions related to the concepts of power and voltage in the post-test, even after our efforts to improve learning in this aspect. We have been able to help students overcome known conceptual difficulties with the proposal of new activities, but some difficulties still a challenge to be outgrown. This fact has shown us that research for improving practice is fundamental to overcome persisting difficulties and is a long-term and constant action. Also, using different resources such as homework activities on the internet, videos and computer simulations have shown to be useful tools as supplement materials.

Simulation of Arc Dwelling Behavior During Bridge-Type Contacts Opening Process for High-Power Relay

The importance of high-power relays used to interrupt dc current has been significantly growing recently. In their arc chambers filled with nitrogen or its mixtures, bridge-type contacts with permanent magnets are major measures widely used for arc extinguish. Arc dwelling for a short duration after arc ignition, until its voltage increases rapidly, plays a crucial role in contact erosion. In this paper, arc dwelling time in a nitrogen environment during the entire bridge-type contacts interruption process of a resistive dc circuit is studied both experimentally and numerically. A multiphysics model coupled with the fluid flow, the temperature, the current density, as well as the E- and M-fields was built based on the magnetohydrodynamics theory for the arc chamber. The model was solved in COMSOL. The external resistive electric circuit was connected to the model, and the electric field in the arc was solved by adopting a floating potential. The detailed arc dwelling process is presented and preliminarily discussed according to the calculated temperature and current density distribution sequences. The calculated arc voltage shows good agreement with experimental results. Furthermore, the influence mechanism of breaking velocity on arc dwelling is analyzed by arc voltage. In this sense, the arc dwelling time could be shortened by increasing the breaking velocity within the reasonable extent.

Handheld augmented reality system for resistive electric circuits understanding for undergraduate students

AbstractAugmented Reality (AR) is a recognized technology having a great potential to enhance the cognitive learning process. In this paper, a mobile AR system is proposed which helps in the understanding of resistive electric circuits for undergraduate engineering students. The designed system employs a smartphone, a measuring instrument, and a resistive circuit on a breadboard. The smartphone captures a photograph of the electric circuit and receives data from the measuring instrument (current and voltage) to calculate theoretical values and generate a layer of virtual objects which is then merged with the original image and displayed on the screen of the smartphone. In order to display the AR, a markless method is developed for a typical circuit for identifying resistors in a circuit and set virtual objects over it. The developed circuit displays (via AR) the theoretical current, voltage, power, and their measured values, as well as the error for each parameter. Technical efficiency of the developed system is 98%. Additionally, a satisfaction qualitative study is presented.

Low voltage electric potential as a driving force to hinder biofouling in self-supporting carbon nanotube membranes

This study aimed at evaluating the contribution of low voltage electric field, both alternating (AC) and direct (DC) currents, on the prevention of bacterial attachment and cell inactivation to highly electrically conductive self-supporting carbon nanotubes (CNT) membranes at conditions which encourage biofilm formation. A mutant strain of Pseudomonas putida S12 was used a model bacterium and either capacitive or resistive electrical circuits and two flow regimes, flow-through and cross-flow filtration, were studied. Major emphasis was placed on AC due to its ability of repulsing and inactivating bacteria. AC voltage at 1.5 V, 1 kHz frequency and wave pulse above offset (+0.45) with 100Ω external resistance on the ground side prevented almost completely attachment of bacteria (>98.5%) with concomitant high inactivation (95.3 ± 2.5%) in flow-through regime. AC resulted more effective than DC, both in terms of biofouling reduction compared to cathodic DC and in terms of cell inactivation compared to anodic DC. Although similar trends were observed, a net reduced extent of prevention of bacterial attachment and inactivation was observed in filtration as compared to flow-through regime, which is mainly attributed to the permeate drag force, also supported by theoretical calculations in DC in capacitive mode. Electrochemical impedance spectroscopy analysis suggests a pure resistor behavior in resistance mode compared to involvement of redox reactions in capacitance mode, as source for bacteria detachment and inactivation. Although further optimization is required, electrically polarized CNT membranes offer a viable antibiofouling strategy to hinder biofouling and simplify membrane care during filtration.

Problem Solving Approach in Electrical Energy and Power on Students as Physics Teacher Candidates

<p>In agreement with students’ conceptual understanding, identifying of problem solving is an important part of physics. This article is to identify the approach used by students in solving a physics problem. The subject of the research were students of physics education year 2014 in Jambi University who had joined basic physics class. The instruments used in this research were DIRECT (determining and interpreting resistive electric circuit concept test) (Engelhardt & Beichner, 2004). Based on the result, 34,1% students still used the memory based approach in problem solving, 52,3% of them used no clear approach, 4,5% used structured manner, 6,82% used unstructured manner and only 2,27% students used a scientific approach to solving the problem. The result showed that many students used no clear approach and memory based approach to solve the problem. It mean that they did not use physics concept in solving the problem and generally they only used the equation they memorized related to the problem they ever did before.</p>

Filtering graphs to check isomorphism and extracting mapping by using the Conductance Electrical Model

This paper presents a new method of filtering graphs to check exact graph isomorphism and extracting their mapping. Each graph is modeled by a resistive electrical circuit using the Conductance Electrical Model (CEM). By using this model, a necessary condition to check the isomorphism of two graphs is that their equivalent resistances have the same values, but this is not enough, and we have to look for their mapping to find the sufficient condition. We can compute the isomorphism between two graphs in O(N3), where N is the order of the graph, if their star resistance values are different, otherwise the computational time is exponential, but only with respect to the number of repeated star resistance values, which usually is very small. We can use this technique to filter graphs that are not isomorphic and in case that they are, we can obtain their node mapping. A distinguishing feature over other methods is that, even if there exists repeated star resistance values, we can extract a partial node mapping (of all the nodes except the repeated ones and their neighbors) in O(N3). The paper presents the method and its application to detect isomorphic graphs in two well know graph databases, where some graphs have more than 600 nodes.

A fluidic circuit based, high-efficiency and large-scale single cell trap.

Single cell traps have important applications in biological cell manipulation and analysis. This paper describes a novel single cell trap design and device with a matrix of cell trap units inspired by an equivalent resistive electric circuit. This fluidic device follows the least flow resistance path principle of such devices allowing deterministic single cell trapping with high efficiency and flexibility for large scale cell patterning.