Electrical & Electronics Engineering - Science topic

The nano layer thickness is very very small layer, otherwise it's cannot use by Resistivity method and it has VES limitation.

Best regards.

P. Hakaew

Dear

You can benefit from this valuable Link about your topic:

"PCB Simulation: How to Simulate a PCB Design"

@https://resources.altium.com/p/pcb-simulation-software

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Also this one:

"PCB thermal calculator & simulation"

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"Five Approaches to Cooling Military Electronics"

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"Basics: Power dissipation and electronic components"

@https://www.evilmadscientist.com/2012/basics-power-dissipation-and-electronic-components/

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Online calculator for PCB circuits

@https://www.multi-circuit-boards.eu/en/index.html

I hope it will be helpful..

Best wishes..

Hi David Martínez-Vargas Janelle M Fine Eric Kenji Lee ! Do any of you still have the Grass S88X Stimulator driver and software? If yes, can you please send it to me at apoorvar@umich.edu? Many thanks!!

If gamma is a complex number it is already in the form you want. The S11 you started with is actually S11(dB) which is 20*log10(abs(a+ib)).

S11(complex) is a+ib.

Sometime a and b are not available in a data file, but S11(dB) is and also the phase S11(radians) or S11(degrees), so you can still get the complex number.

The electrical properties are frequency dependent and are dependent on the electromagnetic field profile around the wire. For example, in a high frequency situation, the electric current will travel close to the surface of the wire. Consider a coaxial cable: if the center conductor is round (circular) and the shield is circular and collinear, the electric field will be evenly distributed around the center conductor and the current (tangential magnetic field) will also be evenly distributed. Hence, the resistance per unit length of the wire will be 1/(2*pi*a*delta*sigma), where a=radius of wire, delta=skin depth, sigma=wire material conductivity.

Now, suppose we have a "star" shaped wire. The electric field (and longitudinal current) will be concentrated at the points of the star. The effective area of the current flow will be reduced in this case and the wire will have a higher resistance than the smooth round wire.

If you have access too electromagnetic field simulator software, why not try some numerical experiments?

ADS, CST MICROWAVE STUDIO, HFSS

Dear Durga Sravan ,

try to measure^[1], if possible, the AC-resistances^[2] (impedances, at 1kHz), also.

Dear

You can benefit from this Link about your topic:

@https://www.topuniversities.com/university-rankings/world-university-rankings/2022

You can enter the name of any university that you want to know its rank in the search box.

I hope it will be helpful...

Best wishes...

From the control view, you have to keep your poles on the left side of the imaginary axis. This means that the amplifier has to be insulated from the oscillator or work at different frequencies. Also usually it is said that in a high-frequency world, the amplifiers oscillate while the oscillator does not!

As a result, I think your question can be answered if you let us more details such as circuit structure, desirable oscillation frequency, type of amplifier, oscillator, and feedback.

Dear sir, I guess the Teensy is used to acquire the signal (use one of the analog inputs; for instance, pins for 14 to 23 Analog). The signal is of course converted (Analog to Digital) inside the Teensy. Then, you can display what you read using SPI (pins 10 to 13 of Teens) on SPI LCD Screen. For the Bluetooth device, I don't know what is it used for; maybe to save the data on an SD card and send the data (acquired ECG) to a remote station (computer I guess). You can use it. It is not difficult to assemble that and programs exist for each task: 1. Acquire analog signal using Teensy; 2. Display a value, figure using SPI of Teensy on an SPI LDC display; 3. Send data using a Bluetooth device.

Yes, the signal will be reflected back and ods not reach the load. At the opposite end, the load will see some impedance varying from short to open depending on the electrical length of the transmission line between shorted point and the load.

Hello,

Few papers are attached for your help.

Thanks,

Dear Meysam Asadi ,

You can use silver foils and glue them with thin film of silver paste. It will work for long time without damage. You can also use thermal conducting ceramic paste, contact the heart think to it and fix the heat think to the chip by a clamp.

Best wishes.

Dear Hassan Nasser I really appreciate your response.

Thank you!!

Dear s.Milad:

You can benefit from this valuable article about your topic:

"Fuzzy Fractional-Order PID Controller for Fractional Model of Pneumatic Pressure System".

Abstract:

This article presents a fuzzy fractional-order PID (FFOPID) controller scheme for a pneumatic pressure regulating system. The industrial pneumatic pressure systems are having strong dynamic and nonlinearity characteristics; further, these systems come across frequent load variations and external disturbances. Hence, for the smooth and trouble-free operation of the industrial pressure system, an effective control mechanism could be adopted. The objective of this work is to design an intelligent fuzzy-based fractional-order PID control scheme to ensure a robust performance with respect to load variation and external disturbances. A novel model of a pilot pressure regulating system is developed to validate the effectiveness of the proposed control scheme. Simulation studies are carried out in a delayed nonlinear pressure regulating system under different operating conditions using fractional-order PID (FOPID) controller with fuzzy online gain tuning mechanism. The results demonstrate the usefulness of the proposed strategy and confirm the performance improvement for the pneumatic pressure system. To highlight the advantages of the proposed scheme a comparative study with conventional PID and FOPID control schemes is made.

@https://www.hindawi.com/journals/mpe/2018/5478781/

I hope it will be helpful...

Best wishes....

The transition to a circular economy is not uniform and varies depending on a series of factors such as the degree of industrialization, the level of technological development, the availability of qualified human resources and access to financing, among others.

Dear Raj:

You can benefit from this valuable Courses about your topic:

"Ansys Learning Fourm HFSS"

In it you will find the answer to all your questions at:

@https://forum.ansys.com/discussions/tagged/hfss/p.

Please go through "Cosimulation Using Ansys HFSS” course to learn about how to do cosimulation using Ansys HFSS and Circuit from below link:

https://courses.ansys.com/index.php/courses/cosimulation-using-ansys-hfss/

You can design the PIN diode equivalent circuit in the Circuit and connect it to the HFSS design to see the performance.

I hope it will be helpful..

Best wishes...

See https://www.researchgate.net/post/Publishing_review_and_original_papers_in_Nature_or_Science and the links given therein.

check out this paper using a Laplace transformation for solving nonlinear nonhomogenous partial equations

the solutions are not trivial which is different if your coefficients and the pressure P are constant

Hopefully it helps

There are 2 answers :

1. Theoretically : Yes, however you need a circuit modification.

- The flyback uses a transformer with air gap. A normal transformer does not have this.

- You can create an isolated dc/dc convertor with a normal transformer, at the cost of an extra inductor, an extra winding and an extra diode. I think it is called the 'forward' convertor.

2. Practically, what you show in the pictures:

- On the left: This is a low-frequency transformer, mains, max. 400 Hz frequency. (with very good iron.)

- On the right : A ferrite transformer, typically used in the horizontal drive circuit of a Cathode Ray Tube television. In these televisions, the horizontal drive circuit :

a. It controls the left-right sweep of the electrons in the tube. The standard is such that the frequency where it operates on, is about 16 Khz. (Depends on the TV standard used.) As such, you CANNOT change the core to an iron core.

b. Usually, this circuit is also used as the power convertor for the whole TV. Apart from the windings for the left-right movement of the electron beam, there are windings for a multitude of voltages in the TV. The most 'visible' of these is the high-voltage (10 kV for black/white, 30 kV for color) to accelerate the electrons toward the screen. The 10 kV, that is straight, single diode rectifier. For the 30 kV, usually a diode voltage tripler is used. Note that, in the picture, the 'bulky' look for the right transformer is caused by this 10 kVolt winding. This needs lots of isolation, creep distance etc. Note that a normal ferrite transfomer, nowadays operating at ~100 to ~200 Khz is much more compact than a 50-60 Hz transformer.

Dear all, please have a look at the following link and the attached file. My Regards

Mustapha Messaoudi

I suggest:

1. https://journals.sagepub.com/home/ije

2. https://aece.ro/about.php

3. https://www.sciencedirect.com/

Dear Anubhav Singh ,

There are some good answers by esteemed colleagues but I want to refer to very basic concepts which are the configurations of both amplifiers: the op amp and the differential and difference amplifier based on a circuit of the op amp.

As both amplifiers has a differential input then both have a differential gain and a common mode gain. In every configuration, there are two input voltages and one output terminal.

The two amplifiers have the same terminology as they have similar configuration but the values of the values of Ad and Ac are surely different.

So, the matter is definition of the performance parameters.

Best wishes

Dear Anubhav Singh ,

The colleagues really gave satisfactory answers to your questions. However, I have to stress the main cause of using the binary numbers in signal processing.

It is the available electronic devices that impose the number system used in digital computers and consequently signal processing.

There are two major electronic devices imposing the binary system:

The memory cells are binary that is a cell sores either logic one or logic zero.

So, to wright or read them directly they have to handle binary numbers.

The other major device is the arithmetic and logic unit. It also use binary numbers in their operations.

So, any other signal format must be converted into the binary from including the samples of analog signals. Every sample must be converted into n bit code. Which is a strings of one and zeros.

The conversion from analog to digital and vice verse is accomplished by A.D converters. According to the required resolution, every sample is represented by an n bits binary codes.

Best wishes

Thanks for responding Mr @Joerg Fricke , Mr @Oussama Laayati and Mr @Rishav Pramanik

I want to clarify my question. Like, when we turn on our mobile phone's bluetooth, it shows nearby by bluetooth devices. In the same way I want to implement such technic using bluetooth module and Arduino nano for detection of nearby active bluetooth devices.

Dear Franklin:

I agree with the opinions of my colleagues mentioned above, that it's difficult to find the problem since we can't see all the settings.

But you could benefit from this valuable article about your topic:

"Heat Transfer Modeling of Power Cables in Tunnels"

@https://www.comsol.com/paper/heat-transfer-modeling-of-power-cables-in-tunnels-18877.

Electric power, in cities or for power plant outflow, is most often transmitted through underground cables. Due to increased electricity demands power suppliers make large investments to house these cables in deep or shallow tunnels.

The thermal environment is complex, with different kind of cables placed in different configurations, transmitting different powers. These are hard to take into account theorically, so thermal simulations using COMSOL Multiphysics® software were undertaken to measure the inaccuracy of the empirical models.

The Conjugate Heat Transfer interface is used, 2D and 3D models were developed and showed that several hypotheses lead to underestimation of the hottest cable temperature and two interesting possibility for improvement were found: the heat transfer correlations and cables proximity effects.

I have attached the pdf files ....

I hope it will be helpful...

With my best regards ...

Dear Bassam:

At the first, and as you know that several different factors influence the potential wind resource in an area. The three main factors that influence power output are: wind speed, air density, and blade radius. Wind turbines need to be in areas with a lot of wind on a regular basis, which is more important than having occasional high winds.

# Wind speed:

Wind speed largely determines the amount of electricity generated by a turbine. Higher wind speeds generate more power because stronger winds allow the blades to rotate faster. Faster rotation translates to more mechanical power and more electrical power from the generator. The relationship between wind speed and power for a typical wind turbine is shown in Figure (a).

Turbines are designed to operate within a specific range of wind speeds. The limits of the range are known as the cut-in speed and cut-out speed. The cut-in speed is the point at which the wind turbine is able to generate power. Between the cut-in speed and the rated speed, where the maximum output is reached, the power output will increase cubically with wind speed. For example, if wind speed doubles, the power output will increase 8 times. This cubic relationship is what makes wind speed such an important factor for wind power. This cubic dependence does cut out at the rated wind speed. This leads to the relatively flat part of the curve in Figure (a), so the cubic dependence is during the speeds below 15 m/s (54 kph).

The cut-out speed is the point at which the turbine must be shut down to avoid damage to the equipment. The cut-in and cut-out speeds are related to the turbine design and size and are decided on prior to construction.

#Air Density:

Power output is related to the local air density, which is a function of altitude, pressure, and temperature. Dense air exerts more pressure on the rotors, which results in higher power output.

#Turbine Design:

Wind turbines are designed to maximize the rotor blade radius to maximize power output. Larger blades allow the turbine to capture more of the kinetic energy of the wind by moving more air through the rotors. However, larger blades require more space and higher wind speeds to operate. As a general rule, turbines are spaced out at four times the rotor diameter. This distance is necessary to avoid interference between turbines, which decreases the power output.

# There's a phenomenon, which referred to as the reduced wake effect:

During curtailment, less power is extracted from the wind and thus the wake effects are reduced. This leads to a wind speed increase at the downstream turbine and therefore to an apparent increase of its available power. This phenomenon is referred to as the reduced wake effect.

# So you could benefit from this valuable article about this topic:

"Analysis of the reduced wake effect for available wind power calculation during curtailment"

# Abstract:

With the increase of installed wind power capacity, the contribution of wind power curtailment to power balancing becomes more relevant. Determining the available power during curtailment at the wind farm level is not trivial, as curtailment changes the wake effects in a wind farm. Current best practice to estimate the available power is to sum the available power calculated by every wind turbine. However, during curtailment the changed local wind conditions at the wind turbines lead to inaccurate results at the wind farm level. This paper presents an algorithm to determine the available power of a wind farm during curtailment. Moreover, results of curtailment experiments are discussed that were performed on nearshore wind farm Westermeerwind to validate the algorithm. For the case where a single turbine is being curtailed, it is shown that the algorithm reduces the estimation error for the first downstream turbine significantly. Further development of the algorithm is required for accurate estimation of the second turbine. All further downstream turbines did not experience a change in wake conditions.

I hope it will be helpful ...

With my best regards ...

finnally i found a solution

close all , clear all ,clc

%% parameters %%

P=1000:70:4000; phi=0.174:pi/50:pi/2; f=250e3; Vo=300; Vg=33.33; n=3/4;

%% Required leakage inductance with respect to operating power rating % and phase shift for DAB converter

[X,Y]=meshgrid(P,phi);

L=((pi*Y-Y.^2)*Vo*Vg)./(2*pi^2*f*n*X);

figure

h=surf(X,Y,L)

colorbar

title('Required leakage inductance with respect to operating power rating and phase shift for DAB converter')

xlabel('Power (W)')

ylabel('Phase shift (rad)')

zlabel('Inductance (H)')

There is no specific answer to your question. to choose the best routing algorithm in an Ad hoc network you must specify the type of application, the size of the network, and the mobility model.

The most known routing protocols are

1- AODV and DSR as reactive protocols.

2- OLSR and DSDV as proactive Protocols.

3- ZRP and TORA as Hebrid Protocols.

I recommend to read and cite the related paper

Both are different things :

1.phase shift between input and output across a device

2. phase shift between current and voltage across a device

Two capacitors in series can not provide phase shift of 180 between input and output. So, it depends upon the quantities in which you need phase shift. No, nowadays amplifiers are available in miniature form or IC form (maybe you can use that, comparable or even smaller than the size of conventional capacitors).

That's how I can help, may be some faculty or researcher from the concerned domain may provide a useful answer and suggestion to your query.

Engineering with computers IF=7.9

Soft computing IF=3.6

Indeed you could benefit from this URL:

Hi, Hooman Firoozi, there is not an easy answer for all questions.

I can share with you the incident characteristic we found on one electric company in Colombia, you can read on

for the last question 4. What is the easiest way to detect and prevent/reduce this type of loss in networks?

I think there is not create a detect system of NTL because of the dynamic behavior of the energy theft when you improve the energy network security, you have a time of response while the new methods for thefts raise from the users. Another important issue is the regulatory law in each country. For example, the law can allow it is cheaper to pay a penalty fee than the energy used in the theft period. So user can prefer to generate NTL instead of paying the energy bill and waiting for the penalty fee.

You have to study several topics you need to mix to understand this complex problem.

Maybe this can help:

Dear Tariq Kanaan sir,

1) Yes both the circuits produces the square wave but the noise immunity in first circuit is more due to the usage of bistable multivibrator (Bistable multivibrator in general are more noise immune due to two threshold voltages: larger hysteresis voltage indicates more noise immunity).

2) The frequency of the generated square wave depends upon the circuit elements (R and C) but the maximum frequency of the opamp will be limited by the slew rate of the opamp.

check this paper for values:

Standard suppliers are CATL, Samsung, LG, BYD

I extracted impact factor and quartile of all mathematics journals based on new report released by Clarivate 2021.

Please, click on the following link:

Dear Franklin Uriel Parás Hernández

I am doubtful on the replacement of XLPE in such a short period. Some European companies are claiming that they are recycling XLPE. Apart from this, on account of much lower loss factor XLPE is likely to continue as a leader for some more time.

Also check http://iopscience.iop.org/article/10.1088/1757-899X/366/1/012044/pdf

The so-called Moore's laws are distinguished by the fact that they are formulated in such a way as to serve as a "self-fulfilling prophecy."

Regards,

Dariusz Prokopowicz

Thank you so much Mr. Cuff, your answer helped me to think more widely. Thanks for telling me about your experience, it is really helpful.

I'm interested

hello could you please me on how to select the PI parameter value for inner current and voltage control loop in AC microgrid

Please read :

An atomistically informed energy-based theory of environmentally assisted failure

S Ganesan, V Sundararaghavan - Corrosion Reviews, 2015 - De Gruyter

https://scholar.google.com/scholar?cluster=4817203216405241660&hl=en&as_sdt=5,38&sciodt=0,38

Ali Zeki

In my first answer, I referred to the symbols in the upper row of the attached file. These replaced those in the lower row which were a former DIN attempt to make German symbols "unique" but those older ones had at least some resemblance to the more widespread symbols.

Also here I have attached the excel sheet that includes the calculator mentioned previously ....

Journal Metrics Reports 2019

Dear Mr Muhammad Ali

You were about to hit the target but missed for just a little bit. Here is the answer to your question in brief.

Transmission lines are classified into two standards.

As per voltage rating, there are 5 types of transmission existing

As per the length of the line, there are 3 types of transmission existing

Once again these standards can vary in different countries. Hope that information will be helpful for you. Good Luck!

There is a misconception that because a voltage source isn't connected to a circuit or load, the voltage doesn't really exist, or its power doesn't go into effect until it is connected to a closed-circuit path. However, this is erroneous.

A voltage source does not need to be connected to anything for voltage to exist. Voltage unconnected is the real voltage. Even if a voltage source is unconnected and not attached to any load, the potential power still exists.

This misconception may stem from the fact that current can only flow when it is in a closed circuit. However, voltage is different. While current can only exist when a circuit is closed, voltage always has potential.

The impedance of an antenna can be anything from a few ohms to very high. A properly designed antenna will match to the impedance of the driving source for optimum power transfer. The 50 ohm value of the port is arbitrary and can be set to any value desired. Cable impedances come in many different values, such as 50, 75 and 300 ohms. Sometimes a low value antenna impedance is desired such as 10 ohms when connected to a low impedance solid state circuit.

I suppose one possibility that should always be considered is that perhaps what we call alpha waves are in fact the recording of the Schumann phenomenon when the brain is not working! Since we cannot really pick a spot on the planet where the Schumann sound is not present your best bet would be to look at brainwave studies on astronauts. There’s a good chance this information is classified.

A forward voltage impulse of one volt amplitude and duration of 500 ns will not damage the solar cell. In forward direction the solar cell is equivalent to a parallel Cf -rf in series with the Rs the series resistance of the solar cell.

rf is the forward junction resistance and and Cf is the forward capacitance of the solar cell and it is composed of two capacitances the junction capacitance and the diffusion capacitance. At the beginning of the voltage pulse applications, the voltage will appear at Rs while the voltage on the capacitance will be zero. With elapsing of time the diode capacitance will be charged and the junction voltage increases. This will continue to the end of the time of the pulse where a part of the voltage will be dropped on the junction and the rest will be dropped on the series resistance. Since the time constant is large because the solar cell is large then the pulse ends with with only a fraction of the voltage is dropped on the junction and the current is still smaller that the maximum forward current that can burn the solar ell.

The series and shunt resistances will remain the same except some heating of the series resistance which may then increase.

In summary the behavior of the solar cell is similar to the behavior of the power diode.

For more information please follow the link:

Best wishes

Dear Meenakshi Kohli ,

You have to investigate and improve the matching between the source impedance and the input of the UHF port. You can measure S11 and see whether the resonance center frequency is lies at the minimum of S11. The minimum must at least lower than S11= -10dBs. May be you need to fine tune the path to the UHF antenna. Also, the radiation resistance may be smaller much deviated from the source resistance.

Best wishes

General Multimeter is simpler and easier instrument for measuring voltage and current.

Dear Meenakshi Kohli ,

You got a number of good answers and I want to make somethings more clear.

The antenna has certain specific resistance which is the radiation resistance Rr and has also some loss resistance Rl

So the input power P= I^2 Rt , Rt=Rr+Rl

I is the effective value of the current.

So, as a rating of the antenna one must construct it to withstand the maximum current in the antenna conductors. This is due to thermal fusing effects of the wires.

The other rating is the maximum voltage that can be applied on the antenna

where P= V^2/Rt

So the antenna must be constructed to withstand the maximum voltage defined by the maximum power the relation given above. The maximum voltage is limited by the breakdown of the gap between the two poles of the antenna as these two points are the nearest from each other.

These simple analysis may answer your question in a simple manner.

Best wishes

Good question

Agreed with the link provided by dear Ijaz Durrani

Much costly and slow process

No

Dear Arbaaz Mahmood

Please see the attached sites

Best regards

The following papers can be useful

Dear Reema Ahmad,

Thank you for your response. I agree with you. You added some very interesting information to our discussion. I also believe that the importance of artificial intelligence is growing in the implementation of this technology in various applications, in various fields, branches and sectors of the economy and in the improvement of research works. Thank you very much for proposing an article on this important issue artificial intelligence.

Greetings, Have a nice day,

Dariusz Prokopowicz