Simple Electrical Circuit Research Articles

Simulation of Electrical System using Bond Graphs and MATLAB/Simulink

Abstract The work shows the use of Bond Graph formalism for modeling dynamic systems. As an example a electrical model is solved by this approach at the level of its physical behavior. In contrast with the classical method, where the equations for individual components are created first and then the simulation scheme is derived on their basis, the described method uses the reverse procedure. In this paper the method of generation of system equations is discussed. From a bond graph diagram of the system, using a step-by-step procedure, system equations may be generated. As a starting point a model of a simple electrical RLC circuit consisting of a resistor, an inductor, and a capacitor is taken. The differential equations describing the dynamics of the system are obtained in terms of the states of the system.

Some Key Issues in Creating Inquiry-Based Instructional Practices that Aim at the Understanding of Simple Electric Circuits

Many students in secondary schools consider the sciences difficult and unattractive. This applies to physics in particular, a subject in which students attempt to learn and understand numerous theoretical concepts, often without much success. A case in point is the understanding of the concepts current, voltage and resistance in simple electric circuits. In response to these problems, reform initiatives in education strive for a change of the classroom culture, putting emphasis on more authentic contexts and student activities containing elements of inquiry. The challenge then becomes choosing and combining these elements in such a manner that they foster an understanding of theoretical concepts. In this article we reflect on data collected and analyzed from a series of 12 grade 9 physics lessons on simple electric circuits. Drawing from a theoretical framework based on individual (conceptual change based) and socio-cultural views on learning, instruction was designed addressing known conceptual problems and attempting to create a physics (research) culture in the classroom. As the success of the lessons was limited, the focus of the study became to understand which inherent characteristics of inquiry based instruction complicate the process of constructing conceptual understanding. From the analysis of the data collected during the enactment of the lessons three tensions emerged: the tension between open inquiry and student guidance, the tension between students developing their own ideas and getting to know accepted scientific theories, and the tension between fostering scientific interest as part of a scientific research culture and the task oriented school culture. An outlook will be given on the implications for science lessons.

Equivalent Source Method for Calculation of Periodic Commutation Electric Circuits

In this paper the equivalent sources method which is intended to calculate the periodically switched electric circuits using harmonic analysis method is described. It is not possible to apply 'the harmonic analysis method to analyze such circuits, since the circuit configuration varies over time. When using the offered method, the switched source of direct voltage is replaced using the equivalent source of variable voltage, for which electric currents, voltages power and other electrical magnitudes are completely the same as in the case of the switched direct voltage source; the main difference is that after such substitution the voltage source becomes non-switched. Then the harmonic analysis method can be readily applied for calculation of the input of separate harmonics into the overall result. The essence of the method is illustrated by calculating the equivalent source for a simple electric circuit operated by first law of commutation. Ill. 6, bibl. 5 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.114.8.697

On the Use of Simple Electrical Circuit Techniques for Performance Modeling and Optimization in VLSI Systems

Leading-edge VLSI systems, essentially multiprocessor systems-on-chip, have a wide range of components integrated together and operating in unison. They can be analyzed as flow networks in which the system performance depends on the bandwidth, transmission time, and queueing delay characteristics of the individual components, their connectivity and interactions, as well as the traffic patterns they encounter. The flow in various parts of the system must ideally be distributed so as to extract the maximum throughput possible with minimum end-to-end delays. Such an ideal distribution for flow networks has previously been obtained using simple electrical circuits. We demonstrate a similar methodology for typical VLSI systems and provide the necessary extensions of the theory. We empirically validate the methodology using a cycle-accurate simulation model as the reference. We find this methodology to supply better distributions in the average case and comparable distributions in the worst case as compared to standard search procedures such as random sampling and simulated annealing. The real strength is that it provides a speedup of several orders of magnitude, i.e., 3-5 orders in our experiments. Thus it is an elegant means for analyzing and optimizing the flow in VLSI systems, which can easily be incorporated into design procedures, compilers and on-chip modules for real-time allocations.

Growth of Al2O3 thin film by oxidation of resistively evaporated Al on top of SnO2, and electrical properties of the heterojunction SnO2/Al2O3

Aiming for the investigation of insulating properties of aluminum oxide (Al2O3) layers, as well as the combination of this oxide with tin dioxide (SnO2) for application in transparent field effect transistors, Al thin films are deposited by resistive evaporation on top of SnO2 thin films deposited by sol–gel dip-coating process. The oxidation of Al films to Al2O3 are carried out by thermal annealing at 500 °C in room conditions or oxygen atmosphere. X-ray diffraction data indicate that tetragonal Al2O3 is indeed obtained. A simple device and electric circuit is proposed to measure the insulating properties of aluminum oxide and the transport properties of SnO2 as well. Results indicate a fair insulation when four layers or Al2O3 are grown on the tin dioxide film, concomitant with thermal annealing between each layer. The current magnitude through the insulating layer is only 0.2% of the current through the semiconductor film, even though the conductivity of the SnO2 alone is not very high (the average resistivity is 2 Ω cm), because no doping is used. The presented results are a good indication that this combination may be useful for transparent devices.

The Effect of Herrmann Whole Brain Teaching Method on Students' Understanding of Simple Electric Circuits

The purpose of this study was to investigate the effect of Herrmann Whole Brain Teaching Method over conventional teaching method on eight graders in their understanding of simple electric circuits in Jordan. Participants (N= 273 students; M=139, F=134) were randomly selected from Bani Kenanah region-North of Jordan and randomly assigned to both teaching methods (Hermann Whole Brain Teaching Method =135, Conventional Teaching Method =138). A multiple choice concept test was developed measuring misconceptions commonly held by eight grade students on simple electric circuits. The results showed that Hermann Whole Brain Teaching Method was more successful than the conventional teaching method in fostering students' understanding of simple electric circuits. However, there was no significant differences attributed to gender or interaction between methods and gender on student' understanding of simple electric circuits. The results suggest that curriculum developers and textbook authors are advised to take into account students' learning styles and characteristics of brain parts as illustrated by Hermann Whole Brain Model in the curricula and textbooks they develop. Teachers are also recommended to focus on individual differences among students and respond to their learning styles during science lessons.

Evolution of a current in a resistor

Abstract The current in a simple electric circuit consisting of a resistor and a power supply is studied under the assumption that the current starts from zero and reaches its maximum value. It suggests that an evolution process of a current occurs approximating the circuit temporarily to an R-L circuit. The current equation is solved analytically using Mittag-Leffler function. The equation was also solved numerically. Results supported the assumed behavior of current to evolve from zero to its saturation value.

Investigation of Passive Film Properties and Pitting Resistance of AISI 316 in Aqueous Ethanoic Acid Containing Chloride Ions using Electrochemical Impedance Spectroscopy(EIS)

The structure and properties of the passive film formed on the surface of AISI 316 stainless steel in aqueous ethanoic acid have been investigated using EIS. Experiments were carried out at 30 oC in different concentrations of ethanoic acid. Effects on the film properties due to the change of electrode potential, exposure durations and addition of chloride ions to the electrolyte were also studied. Impedance parameters were determined using simple model and equivalent electrical circuit. Results suggest the formation of multilayered passive film on the steel surface. The film possessed dual structure. Inner layers were thin and compact, whereas the outer layer was porous and defective. The measured capacitive behavior was of non ideal nature and hence replaced by constant phase element or CPE. Formation of the passive film and the change in its structure has been explained using impedance parameters.

A calming influence

A simple passive electrical circuit that is able to suppress Q -switching instabilities in mode-locked semiconductor quantum dot lasers has been demonstrated. By connecting frequency-selective electrical components to the absorber section of a monolithic two-section tapered laser, a team at the Technical University of Darmstadt in Germany were able to eliminate the Q -switching instabilities and extend the stable mode-locking range.

A critical assessment of the Mott-Schottky analysis for the characterisation of passive film-electrolyte junctions

The widespread use of the Mott-Schottky plots to characterize the energetics of passive film/electrolyte junction is critically reviewed in order to point out the limitation of such approach in describing the electronic properties of passive film as well in deriving the correct location of the characteristic energy levels of the junction. The frequency dependency of M-S plots frequently observed in the experimental data gathered in a sufficiently large range of frequency is extensively discussed for a relatively thick (160 nm) thermally aged amorphous niobia (α-Nb2O5) film immersed in electrolytic solution. The relatively simple equivalent electrical circuit describing an ideally blocking behaviour of the junction allows a direct comparison of the experimental data analysis based on the use of Mott-Schottky or amorphous semiconductor Schottky barrier interpretative models. Moreover the theoretical simulations of the M-S plots based on the theory of crystalline semiconductor suggest an electronic structure of the investigated passive film containing a distribution of localized electronic states deep lying in energy in agreement with the model of amorphous semiconductor Schottky barrier.

Geoelectrical Classification of Gypsum Rocks

Gypsum rocks are widely exploited in the world as industrial minerals. The purity of the gypsum rocks (percentage in gypsum mineral in the whole rock) is a critical factor to evaluate the potential exploitability of a gypsum deposit. It is considered than purities higher than 80% in gypsum are required to be economically profitable. Gypsum deposits have been studied with geoelectrical methods; a direct relationship between the electrical resistivity values of the gypsum rocks and its lithological composition has been established, with the presence of lutites being the main controlling factor in the geoelectrical response of the deposit. This phenomenon has been quantified in the present study, by means of a combination of theoretical calculations, laboratory measurements and field data acquisition. Direct modelling has been performed; the data have been inverted to obtain the mean electrical resistivity of the models. The laboratory measurements have been obtained from artificial gypsum-clay mixture pills, and the electrical resistivity has been measured using a simple electrical circuit with direct current power supply. Finally, electrical resistivity tomography data have been acquired in different evaporite Tertiary basins located in North East Spain; the selected gypsum deposits have different gypsum compositions. The geoelectrical response of gypsum rocks has been determined by comparing the resistivity values obtained from theoretical models, laboratory tests and field examples. A geoelectrical classification of gypsum rocks defining three types of gypsum rocks has been elaborated: (a) Pure Gypsum Rocks (>75% of gypsum content), (b) Transitional Gypsum Rocks (75–55%), and (c) Lutites and Gypsum-rich Lutites ( 800 ohm.m, can be exploited as industrial rocks. The methodology used could be applied in other geoelectrical rock studies, given that this relationship between the resistive particles embedded within a conductive matrix depends on the connectivity of the matrix particles.

Local electrical characterization of Ag conducting chalcogenide glasses using electric force microscopy

Local electrical properties of Ag x (Ge 0.25Se 0.75) 100 − x glasses with x = 5, 15, 20 and 25 at.% were investigated by electric force microscopy. The EFM contrasts electrically evidenced phase separation in these glasses with a percolation of a Ag-rich phase at the origin of a sudden jump in conductivity for x = 8–10 at.%. A method to obtain information about the electrical permittivity, through a simple modelled electrical circuit, is described in detail. The use of the model helped in showing a continuous increase in the permittivity of each present phase (Ag-rich phase and Ag-poor phase) when the silver content in the glasses increased. The result, in turn, indicates that both phases have their composition that changes when more silver is added to the Ge–Se backbone. This result departs from previous assumptions of a constant composition for the Ag-rich phase.

Basic study of a transcutaneous information transmission system using intra-body communication

The transcutaneous communication system (TCS) is one of the key technologies for monitoring and controling artificial hearts and other artificial organs in the body. In this study, we have developed a new TCS that uses the human body as a conductive medium. Having no energy conversion from electric currents into electromagnetic waves and light provides energy-saving data transmission with a simple electrical circuit. Each unit of the TCS mainly consists of two electrodes, an amplitude shift keying (ASK) modulator and an ASK demodulator (carrier frequency: 4 and 10 MHz). A resonant frequency of an L-C tank circuit including the capacitance component of the body is tuned into each carrier frequency in order to apply the data current effectively into the body. Performance of the TCS was evaluated by a communication test on the surface of a human body. The TCS was able to transmit 3,315 bytes of data bi-directionally at a transmission rate of 115 kbps from a left wrist to a right forearm, to an abdomen and to a left calf without communication error. The power consumption of each TCS unit was 125 mW with an ASK modulated current of 7 mA (RMS). While further study is required to secure its safety, the TCS promises to be a next-generation transcutaneous communication device.

Development of a Three-Tier Test to Assess Misconceptions About Simple Electric Circuits

ABSTRACT The authors aimed to propose a valid and reliable diagnostic instrument by developing a three-tier test on simple electric circuits. Based on findings from the interviews, open-ended questions, and the related literature, the test was developed and administered to 124 high school students. In addition to some qualitative techniques for establishing the validity, some quantitative techniques were also used. Consequently, Cronbach's alpha reliability coefficient was estimated for the test as .69, and results revealed that the test scores could be a valid and reliable measure of students’ qualitative understanding of simple electric circuits.

Electrical oscillations induced by the metal-insulator transition in VO2

We systematically investigate the characteristics of an electrical oscillation observed in two-terminal vanadium dioxide (VO2) devices. These oscillations are observed at room temperature in a simple electrical circuit without inductive components. The circuit is composed only of a dc voltage source, the VO2 device, and a standard resistor connected in series with the device. We explain why the observed oscillations are a result of the percolative metal-to-insulator transition (MIT) of VO2 and the coexistence of the metal and insulating phases. Specifically, oscillations are attributed to the construction and destruction of capacitive regions composed of regions of the semiconducting phase, (as dielectric material) and metallic phase electron carriers, induced by the MIT (as capacitor electrodes). Since the coexistence of these phases—and thus the capacitive regions—is destroyed by elevated temperature, the MIT oscillation is not explained in terms of significant heat input but rather in terms of a voltage-triggered effect. It is also discussed whether the current jump at the onset of the oscillations is driven by Mott physics or by Peierls physics relying on a structural phase transition. Furthermore, the electrical parameter space surrounding these oscillations is explored, and a generation window is identified. Within this generation window, the oscillation frequency can be continuously tuned by adjusting applied voltage or by an external circuit component, such as resistor or added capacitor. The frequency of oscillations can be increased up to >1 MHz.

10.1007/s11449-008-1013-1

It is shown that the effect of hole-burning under conditions of coherent population oscillations as well as the pulse delay in a saturable absorber (a modification of the slow light effect) can be interpreted, in a comprehensive way, in terms of {\it intensity spectrum} of the and {\it intensity-related susceptibility} of the non-linear medium. The physical content of these effects is illustrated by a simple electric circuit with a non-linear resistor which realizes a full analog of the saturable absorber. In this case the effect of hole-burning in the absorption spectrum of the medium is converted in to the effect of hole-burning in the frequency dependence of resistance of the non-linear resistor and the effect of slow light -- in to the effect of slow current.

An Examination of Controlling a Wind Turbine with a Simple Electric Circuits Model of a Synchronous Generator and a Resistance

An Examination of Controlling a Wind Turbine with a Simple Electric Circuits Model of a Synchronous Generator and a Resistance

Direct metal printing of 3D electrical circuit using rapid prototyping

Rapid prototyping (RP) is a direct-writing technology that offers several advantages over subtractive manufacturing processing, including low material consumption and easy customizability. Recently, this technique has been studied not only manufacture production parts but also electronic manufacturing applications. In this research, the design and manufacture of printed circuits using RP printing of lead-based alloy having low melting temperature were performed. The bonding strength was measured by strength test. Average bonding strength between solder and universal printed circuit board (PCB) was 69.5 kPa. A simple electrical circuit with five crossing points was constructed to reduce the size of the circuit. In the crossing points, polycaprolactone (PCL) was deposited between top and bottom interconnects to insulate the printed line. Through this process, the size of the circuit board can be reduced about 34% and the number of processing steps was decreased.

Electrochemical impedance spectroscopy at single-walled carbon nanotube network ultramicroelectrodes

Electrochemical impedance spectroscopy (EIS), coupled with chemical vapour deposition (CVD) grown single-walled carbon nanotube (SWNT) network disk-shaped ultramicroelectrodes (UMEs), gives stable, very well-defined and highly reproducible EIS responses for electrolysis of a simple outer sphere redox couple (FcTMA +/2+). The resulting EIS data can be fitted accurately using a simple electrical circuit model, enabling information on double-layer capacitance, diffusion coefficient of the electroactive species and the rate constant of ET ( k 0) to be extracted in a single EIS experiment. These values are replicated for a range of mediator concentrations and UME sizes (in the range 25–100 μm diameter) demonstrating the robustness of the method. These initial studies bode well for impedance based electroanalysis using SWNT network UMEs.

Design Framework for Electrokinetically Enhanced Dewatering of Sludge

Electrokinetic (EK) dewatering involves the application of a (direct current) voltage across sewage sludge, driving water under an electrical gradient from the positive electrode (anode) to the negative electrode (cathode). Researchers have shown the technique to be efficient means of driving off water from the sludge, thus improving strength and reducing volume. This paper presents an integrating framework for EK dewatering under constant voltage and constant current conditions, founded on the mathematics of simple electrical circuits and demonstrated by laboratory experimentation. The derived equations and experimental results showed that electroosmotic flow rate decreases with time when dewatering with constant voltage and is constant when constant current conditions are maintained. Having a linear relationship between flow and time, EK dewatering with constant current not only enhances the sludge dewatering efficiency, but also has the advantage of simplifying design procedures.