Voltage Graphs Research Articles

МЕТОД ПІДВИЩЕННЯ ЗАВАДОСТІЙКОСТІ СИСТЕМИ ВИЯВЛЕННЯ, РОСПІЗНАВАННЯ І ЛОКАЛІЗАЦІЇ ЦИФРОВИХ СИГНАЛІВ В ІНФОРМАЦІЙНИХ СИСТЕМАХ

In the process of detection, recognition, and localization of the single means of silent retrieval of information in information systems, the urgent issue is the increase of noise immunity. The article explores the features of using low-pass filters with a quadratic and linear response dependence on the input signal. It is shown that the principle of operation of the filters is that the summation process is performed. In this case, the useful signal is summed coherently, and the interference signal is incoherent, that is, the useful signal increases, and the interference signal decreases. When exposed to inputs, linear and quadratic filters, a rectangular pulse that simulates the signal of modern digital non-voice information, the parameters necessary for use in the future, such as mathematical expectation, correlation coefficient, variance, root mean square, the ratio of signals to interference in temporal and spectral form. We have determined a payoff ratio that shows the efficiency of using low pass filters. The graphs of the envelope voltage at the output of the ideal bandpass filter when exposed to the input of a rectangular pulse - the signal of the means of silent information acquisition, with different duration. The filtration process was simulated at different correlation coefficients, which confirmed the possibility of signal isolation of the means of silent information acquisition by the method of determining the two-dimensional probability density of the interference signal and the background of the general signal. The process of increasing the noise immunity of the system as a whole is considered, it is proved that the increase of noise immunity by 23 % of the system of identification, recognition and localization of the means of silent retrieval of information is achieved by using, in the process of signal processing, narrow-band filters of low frequency.

Automation algorithm to detect and quantify Electrocardiogram waves and intervals

Electrocardiography is the principle of recording the electrical activity of the heart over finite duration of time. It is one of the most practiced methods to detect abnormalities in the heart's electrical, arterial and muscular systems. Electrocardiogram is the voltage versus time graph obtained from the Electrocardiography machine. Automated analysis makes detection of Electrocardiogram findings and consequently determination of pathological abnormalities without human intervention possible. To achieve this goal we process digital Electrocardiograms to quantify the amplitudes and durations of waves and intervals, that is necessary for the automated analysis to find the pathological abnormalities. The proposed method processes Electrocardiograms and localizes the P, Q, R, S and T waves, subsequently it measures the PR, QT and ST intervals and segments.

On differential depletion length of Schottky diodes with copper-nickel alloy metal of front contact

This work was prepared in two sections; the first section describes how to alloy Schottky diodes and aims to understand how metal alloys affect the essential parameters of Schottky diodes at the metal-semiconductor interface. The second section covers the varying differential depletion length in (Cu% Ni%)/n-Si/Al binary-alloyed Schottky diodes. After collecting data, the characteristics of Schottky diodes are calculated by plotting them with an increasing percentage ratio of the first element. We see that alloyed Schottky diode characteristics significantly depend on the mass percentage ratio of the first element. Significant results are seen: first, Vbi (built-in potential) directly affects the characteristics of Schottky diodes with a turning point occurring at the Vbi point on the axis, and second, the built-in potential plays a key role in Schottky diode characteristics. Estimation of the depletion length depends on the built-in potential. For the forward and reverse bias cases, the depletion length versus voltage graphs are identical, but with their symmetry mirrored. Analyzing the differential depletion lengths, it is easily seen that they have higher or lower values compared to the zero depletion length for the forward and reverse bias cases, respectively. When the depletion length formula is expanded in a series, new equations are obtained to show significant effects on Schottky diode characteristics.

On Arc-Transitive Metacyclic Covers of Graphs with Order Twice a Prime

Quite a lot of attention has been paid recently to the characterization and construction of edge- or arc-transitive abelian (mostly cyclic or elementary abelian) covers of symmetric graphs, but there are rare results for nonabelian covers since the voltage graph techniques are generally not easy to be used in this case. In this paper, we will classify certain metacyclic arc-transitive covers of all non-complete symmetric graphs with prime valency and twice a prime order $2p$ (involving the complete bipartite graph ${\sf K}_{p,p}$, the Petersen graph, the Heawood graph, the Hadamard design on $22$ points and an infinite family of prime-valent arc-regular graphs of dihedral groups). A few previous results are extended.

Enhanced Thermoelectric Conversion Efficiency of CVD Graphene with Reduced Grain Sizes

The grain size of CVD (Chemical Vapor Deposition) graphene was controlled by changing the precursor gas flow rates, operation temperature, and chamber pressure. Graphene of average grain sizes of 4.1 µm, 2.2 µm, and 0.5 µm was synthesized in high quality and full coverage. The possibility to tailor the thermoelectric conversion characteristics of graphene has been exhibited by examining the grain size effect on the three elementary thermal and electrical properties of σ, S, and k. Electrical conductivity (σ) and Seebeck coefficients (S) were measured in a vacuum for supported graphene on SiO2/Si FET (Field Effect Transistor) substrates so that the charge carrier density could be changed by applying a gate voltage (). Mobility (µ) values of 529, 459, and 314 cm2/V·s for holes and 1042, 745, and 490 cm2/V·s for electrons for the three grain sizes of 4.1 µm, 2.2 µm, and 0.5 µm, respectively, were obtained from the slopes of the measured σ vs. graphs. The power factor (PF), the electrical portion of the thermoelectric figure of merit (ZT), decreased by about one half as the grain size was decreased, while the thermal conductivity (k) decreased by one quarter for the same grain decrease. Finally, the resulting ZT increased more than two times when the grain size was reduced from 4.1 µm to 0.5 µm.

Comments on the Langmuir probe measurements of radio-frequency capacitive argon–hydrogen mixture discharge at low pressure

In this paper, the current–voltage graphs of discharge in the chamber of capacitive coupled radio frequency (CCRF) at low pressure were presented for Langmuir probe. The Langmuir probe measurements for estimating the electron density and temperature in capacitive coupled discharges at low pressures were presented and the electron temperatures of the Ar–H2 mixture discharge generated at different conditions were reported using the Langmuir probe. The focus of this study is that the CCRF discharge can be determined and explained using the characteristics of plasma by means of Langmuir probe measurements for the different hydrogen rates in Ar–H2 mixture discharge. The measurement results of Langmuir probe gave values around 1015 m−3 for the electron density. The floating potential depended on the electronegative gas amount. It was found that the increase of hydrogen gas amount in the mixture discharge caused the decrease of the floating potential. Also, a decrease in the argon (Ar) metastable with the increase in hydrogen (H2) content was obtained. When the applied radio frequency (RF) power was increased, the thickness and collisionless sheath occurring at lower RF power could transform to thin sheath.

Synthesis of carbon nanoparticles in combined RF-DC plasma

In this work carbon nanoparticles were synthesized in combined RF-DC plasma. To synthesize carbon particles a graphite target was used. The time of synthesis of carbon particles was fixed using a self-bias voltage (Vdc). The SEM image and the chemical composition of the samples were obtained, and the particle size distribution was constructed. SEM images show synthesized spherical nanoparticles with diameters from 80 to 500 nm in dependence on plasma parameters. Self-bias voltage dependence on time at different plasma parameters (gas pressure and discharge power) has been obtained. The graph of particle synthesis time and DC voltage was shown. It was determined that the increase of DC voltage leads to the decreasing of particle synthesis time. Thus, one can conclude that growth of particles in plasma medium can be controlled by DC voltage value.

Investigations and Analysis of PV - Battery based Micro grid Energy Management System

This paper deals with the management of Energy Management System (EMS) connected in a micro grid with a PV array and regulate the battery charge, hold and discharge operations using DC-DC bidirectional converter based on the requirement of the Load. The PV array along with the battery and load is simulated for various conditions such as PV supplying and charging the battery, PV system supplying only the load, battery supplying the load and PV-Battery both supplying the load. The output parameters like voltage, current and power graphs are plot-ted and analyzed for each condition. The entire paper is simulated on Matlab-Simulink environment.

Determination of the Actual Amount of Insolation Absorbed by a Photovoltaic Panel (125w)

The determination of the ability of the Photovoltaic cell in absorbing radiation was performed, taking into cognizance the fact that photovoltaic panels have the ability to harness solar energy incident on it in the form of radiation. It utilized the hourly production of open circuit voltage for a 125W module Photovoltaic panel made of silicon material. The solar panel was exposed to the open atmosphere from sunrise to sunset, precisely from 5.00am to 7.00am, with no obstruction from heights, high rise buildings and tall trees including towers. The photovoltaic panel was brought to ambient temperature and results were taken in clear sky weather condition in the neighborhood of ±10 minutes to the hour mark. The voltage output was recorded with the aid of a digital multimeter and a Power model was used to determine the actual amount of radiation available and a plot of voltage V hours and Watt V hour when done, showed the same pattern as that of Adnot, Haurwitz and Alboteani et al. results. The hourly variation of voltage graph when assessed, showed an ascendancy as the hour increased to a maximum of 20.65Volts at mid day and then a decrease to 0 volts at twilight (7.00pm) on the 11th day of November, 2017. The same ascendancy and decrease patterns were also displayed by the hourly variation of absorbed power. Thus, photovoltaic panel output varies with the sun hours like solar radiation varies with the sun hours, when results are obtained are obtained under stated conditions. Hence, results stands validated.

Virtual lab based real-time data acquisition, measurement and monitoring platform for solar photovoltaic module

The work presents real-time data acquisition and monitoring of solar photovoltaic modules using Lab-VIEW. A graphical program has been developed to obtain efficiency and fill factor of solar PV module. Afront panel is designed, displaying all the acquired data such as; voltage, current, solar radiation, ambienttemperature, humidity, Current vs. Voltage and Power vs. Voltage graphs which make it very useful tounderstand the performance behavior of the solar photovoltaic module in real time. Data acquisition andmonitoring for solar panels of different ratings are carried out. This tool is an effective platform for experimentalstudy in the laboratory of different solar photovoltaic modules with access to real-time data.

Photon-assisted transport through a 1D-dot-graphene similar to STM model device

By using the nonequilibrium Green function method, the photon-assisted electron transport through a graphene-based device similar to STM model is studied theoretically and numerically. The device is composed of a single central site (quantum dot) modulated by an oscillating electric field, a one-dimensional quantum wire and a two-dimensional graphene sheet. Some interesting results on transmission probability and current–voltage ([Formula: see text]–[Formula: see text]) characteristics of the device are given in this paper. In the presence of an oscillating electric field, we find that besides the central two transmission peaks caused by graphene part, there appear photon-assisted peaks which are distributed on both sides of the Fermi level. The positions of the photon-assisted peaks are linear to the frequency of the oscillating electric field, and the widths of the photon-assisted peaks are relevant to the amplitude of the oscillating electric field. It is found that the current–voltage graphs exhibit step growth due to the existence of photon-assisted tunneling. We hope these results may have guidance meaning for the fabrication of optoelectronic devices.

Applications of ordinary voltage graph theory to graph embeddability

AbstractLet p be a prime greater than 5. We show that, while the generalized Petersen graphs of the form have cellular toroidal embeddings, they have no such embeddings having the additional property that a free action of a group on the graph extends to a cellular automorphism of the torus. Such an embedding is called a derived embedding. We also show that does have a derived embedding in the torus, and we show that for any odd q, each generalized Petersen graph of the form has a derived embedding in the Klein bottle, which has the same Euler characteristic as the torus. We close with some comments that frame these results in the light of Abrams and Slilaty's recent work on graphs featuring group actions that extend to spherical embeddings of those graphs.

Virtual lab based real-time data acquisition, measurement and monitoring platform for solar photovoltaic module

Abstract The work presents real-time data acquisition and monitoring of solar photovoltaic modules using LabVIEW. A graphical program has been developed to obtain efficiency and fill factor of solar PV module. A front panel is designed, displaying all the acquired data such as; voltage, current, solar radiation, ambient temperature, humidity, Current vs. Voltage and Power vs. Voltage graphs which make it very useful to understand the performance behavior of the solar photovoltaic module in real time. Data acquisition and monitoring for solar panels of different ratings are carried out. This tool is an effective platform for experimental study in the laboratory of different solar photovoltaic modules with access to real-time data.

Effect of Ag and Ti electrodes on capacitance tunability of oxygen-deficient SrTiO3 based MIM varactors prepared by plasma sputtering

The role of oxygen deficiencies on the electrical performance of SrTiO3 films is investigated by depositing on the stack of TiN/Ti/SiO2/Si films using radio-frequency (RF) and direct current (DC) magnetron sputtering systems operating in oxygen-deficient plasma environment. Electrodes of silver (Ag) and titanium (Ti) are used to observe the effects of their sizes on the electrical properties of the SrTiO3 films. It is found that the nonlinearity in capacitance–voltage graphs (capacitance tunability) of the varactor can be controlled by varying the electrode area. In addition, the material of the electrode plays a vital role in controlling the non-linearity in the capacitance of the oxygen-deficient SrTiO3 dielectric films with varying voltage. It is found that the silver top electrode instead of titanium, delivers better performance with high capacitance tunability, low leakage current and good quality factor. Post deposition annealing at 550 °C in nitrogen ambient, creates more oxygen deficiencies in SrTiO3 film thereby increasing the linearity of the capacitance–voltage graph and decreasing the capacitance tunability.

Моделирование вентильно-индукторного электровибропривода

The article deals with the issue that there is no study on designing switched reluctance electric vibration drives. Mathematical models of electromechanical converter and electronic commutator with 90-degree motor phase commutation algorithm are presented. The interdisciplinary calculation of the built models was carried out. The results of modeling and simulation are motor windings currents and induced voltage graphs. The expe­rimental prototype of the switched reluctance vibration drive with the microprocessor-based control system is developed and manufactured. The experimental research that proves the models adequacy has been performed.

Three-dimensional modeling of solid acid fuel cell with CsH2PO4-MOA (micro-arc oxidation alumina) composite electrolyte

In this study, a three-dimensional, steady state model has been developed for a single planar solid acid fuel cell (SAFC) with CsH2PO4-MOA composite electrolyte. The model considers all of the fuel cell components (flow channels, gas diffusion layers, catalyst layers, and electrolyte). This model describes the electrochemical reactions on the active areas of the anode and cathode electrodes, and transport phenomena that occurring in each part of the fuel cell consisting of, fluid flow in flow channels, diffusion of reactants in gas diffusion layers (porous medias), and ions transport within the electrolyte. The model is solved in a 3D environment using COMSOL MULTIPHYSICS software. Finally the model results validated by the experimental data (current density–voltage graph). The advantage of this model is the prediction of the SAFC behavior in different operational conditions.

Using conics to construct geometric 3-configurations, part I: symmetrically generalizing the Pappus configuration

The \((9_{3})\) Pappus configuration can be realized as a geometric configuration with 3-fold rotational symmetry; using this 3-fold rotation, its Levi graph (the incidence graph for the configuration) can be quotiented by the automorphism corresponding to the 3-fold rotation to form an edge-labelled \(K_{3,3}\). This graph quotient, a type of voltage graph, is called the reduced Levi graph of the configuration. In this paper, we generalize this rotational realization of the Pappus configuration by developing a construction technique for a family of geometric configurations with m-fold rotational symmetry for any \(m \ge 3\) whose reduced Levi graphs are all labelled versions of \(K_{3,3}\). The constructions use primarily straightedge-and-compass techniques, along with the construction of certain conic sections.

Optical and electrical characterization of ZnO/CuO heterojunction solar cells

This paper reports the fabrication and characterization of nontoxic heterojunction of ZnO/CuO. The films were characterized through X-ray diffraction, UV spectroscopy and field emission scanning electron microscope (FESEM). The valence and conduction band edges were measured through Photo-Electron spectroscopy in air. The electrical parameter for FTO/ZnO/CuO/In heterojunction diode such as ideality factor, barrier height, and series resistance were calculated by using conventional forward bias I–V characteristics and also verified with the help of Cheung method. The high value of ideality factor was attributed to high series resistance, defects, other phases of CuO and recombination at interface and within bulk. The double logarithmic graph of current and voltage showed that the transport mechanism is due to the space charge limited current and trapped charge limited current. Photovoltaic parameters Voc of ∼190mV and Jsc of ∼0.40mA/cm2 of FTO/ZnO/CuO/In heterojunction were recorded.

Design and Analysis of Flipped Voltage Follower for Different Aspect Ratio

paper identifies a conventional flipped voltage follower (FVF) for high performance, low-voltage and low-power applications. This basic circuit is used as a voltage buffer, impedance matching and a level shifter. It presents more suppleness in contrast to the basic voltage follower as dc voltage level can be amended by varying aspect ratio of the MOS transistors. However, gain of the flipped voltage follower can be altered by scaling the aspect ratio (W/L) ratio of the transistors. This circuit is an essential building block for the analog circuits as it replicates the input voltage and voltage accuracy is a vital factor for high performance circuits. In this paper, proposed circuit has been designed and simulated on 45nm channel length technology. Simulated results for varying aspect ratio, W/L of 1, 2 and 3 are shown in the results with the help of input and output voltage graphs. The output voltage comes to be 95%, 90% and 85% of input voltage for W/L ratio of 1, 2 and 3 respectively.

Oriented gain graphs, line graphs and eigenvalues

A theory of orientation on gain graphs (voltage graphs) is developed to generalize the notion of orientation on graphs and signed graphs. Using this orientation scheme, the line graph of a gain graph is studied. For a particular family of gain graphs with complex units, matrix properties are established. As with graphs and signed graphs, there is a relationship between the incidence matrix of a complex unit gain graph and the adjacency matrix of the line graph.