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My name is Sandeep. I am the CEO and founder of Space to Space. I am doing my MS in Data Analytics for Science at Carnegie Mellon University. I did my MS in High Energy Physics from IIT( Indian Institute of Technology).
Space to Space is an ambitious project that could launch up to 30 Kg payloads., consecutively and assemble them in space.
As a physicist, my approximation of coil guns and linear motors leads me to believe that sticking payload mass up to 30 Kg will make this mass-driver practical and will reduce much technical complexity. We want to build this as a long 50Km long. We are building a solid business plan to raise funding for that, and we are now able to assure returns to investors. We raised $100k in pre-seed. We want to do a system-level simulation for linear motors or coil guns to know which is the cheapest and least complex. Even our research found that making our own power-generating system is more efficient and long-lasting than saving energy in supercapacitor banks.
I used Ansys Maxwell, which is not useful at high frequency. So, we want to partner with a university to do a simulation at a system level to study feasibility and economics.
Which universities or faculties are best for this, I need your help
Yours Faithfully
Sandeep
Have any of you come across in publications the definition of the left-side limit of 1/f noises ?
Is there any article or project about interaction of the "Schumann Resonance" on the brain alpha or theta waves?
- The Schumann resonances (SR) are a set of spectrum peaks in the extremely low frequency portion of the Earth's electromagnetic field spectrum :: Schumann Resonance Freq. : 7.83 Hz
- Alpha waves are neural oscillations in the frequency range of 8–12 Hz
More:
Best Regards
I am currently studing Electrical & Electronics Engineering. For my individual research my institution asked to do only software or simulation based research. Please suggest an IOT or electronics side topic without hardware implementation.
we think of a point as a spot in an Euclidean plane
indicating a position.Intuitively we assign arbitrary
framework.The confusion (for me) is when
we consider a line segment.It is made of
infinite points aligned in a certain direction.
So a segment results when all these “ directions”
are added vectorial, but a zero vector is
conceptually an infinite direction entity
so how is this vector direction specified for
a point nathematically. physically of course
we have a visible dot with visible dimension,
Any insight or explanation from all sources
is welcome.
Good day Fellow Electrical/Electronic Engineers
I am having a conceptual challenge here when deriving the DC Current transfer functions (i.e Relationship between Input Current (Ii) from Unregulated DC input power supply and Load Current (Io) drawn by the load from the regulated Boost Converter operating in Continuous Conduction mode).
So the challenge is this, when i use the Volt-Second balance equations and derive the ON-time and OFF-time ratios which are equal to the Voff and Von voltage ratio....i can actually replace the ON-time with Voff, and OFF-time with Von in the Duty cycle equation to get a relationship between Vin (unregulated DC voltage input) and Vo (Regulated DC voltage output) connected by the Duty cycle for switching ON and OFF the MOSFET or BJT switches. Using the Power Balance equation, i.e Pin=Pout, which implies 100% efficiency, assuming no power losses in the rectifier diode when forward biased and the BJT in saturation mode, i then found that Ii=Io/(1-D).
Now, if i try to derive this expression, i.e Ii=Io/(1-D), using basic concepts i get stuck. WHY? In continuous conduction mode, the Inductor current of the Boost regulator is not allowed to discharge till the Inductor current reaches 0A or NO conduction in the OFF-state. This means the inductor does not completely discharge before the next ON-state cycle begins. Now, during the OFF-state of the BJT or MOSFET switch, the inductor current discharges and the current waveform is a negative gradient moving from the peak inductor current to some arbitrary current below the average inductor current=input current (Ii). Literature seems to show the average load current as Io=Ii*Toff/T=Ii*(1-D)...which implies Ii=Io/(1-D).
However, when i analyze this i actually get confused because then it implies that the total charge discharged during the OFF-state is Ii*Toff and that charge which is discharged during the OFF-state actually charges the output Capacitor of the Boost Regulator with Io*Ton charge and also supplies the load with Io*Toff charge which implies that during the OFF-state the inductor charges the Capacitor with enough charge that it, the Capacitor, can supply the load Io current for Ton duration during the ON-state when the inductor is cut-off from the output circuit by the rectifier diode. It also means that the inductor supplies Io current for Toff duration during the OFF-state.. However, where does this charge come from....If Ii*Toff=Io*Ton+Io*Toff=Io*(Ton+Toff)=Io*T...this implies that the charge to charge the capacitor and supply the load during the OFF-state is actually the total charge, or Area, under the current discharge waveform of the Inductor in the OFF-state which contradicts the Continuous Conduction Mode philosophy. Who can assist?
Is synergetic control a model-free or model-based approach? Please tell me the reasons.
How about PID control?
There is usually airgap between a radiating element and metasurface and I want to calculate the phase delay analytically. Like what is the reflecting phase from the meta? What is the phase delay from the metasurface to the antenna?
Thanks in advance.
I have made connections as per the datasheet and I am getting HO output but I am facing an crucial problem, my HO and VS is internally shorted and so is LO and COM. This should not be the case in my opinion. I am getting a perfect output at HO which is apparently the same output for VS as they are shorted but I am not getting any output at Lo, I think that is because it has gotten internally shorted with COM. Could you please suggest me what can I do about it? I have to get it running.
I want to design an 1000 Watt inverter using SMPS. It's my first time when I'm designing an inverter. I'm confused regarding calculated part. From where I start calculation and also I want to design battery charger with protection for this inverter. What factors I need to keep in mind during calculation of inverter and battery charger?
AI and machine learning (ML) are being utilized to tackle complicated issues and increase efficiency in a variety of sectors. Here are some instances of how AI and ML are being applied in various industries:
- AI and machine learning are being utilized in healthcare to evaluate medical pictures, aid with diagnosis, and build individualized treatment regimens. They are also used to identify people who are at risk of developing certain diseases and to create novel medications.
- Finance: AI and ML are being used to detect and prevent fraud, evaluate financial markets, and generate predictions about market movements. They are also utilized to deliver customized financial advice and to automate a variety of typical financial duties.
- Retail: Artificial intelligence and machine learning are being used to optimize prices and inventory, customize suggestions, and increase supply chain efficiency. They are also utilized to assist merchants in better understanding their clients and improving the online purchasing experience.
- Manufacturing: Artificial intelligence and machine learning are being utilized to streamline manufacturing processes, increase quality control, and minimize downtime. They are also used to forecast equipment breakdown, allowing maintenance to be arranged ahead of time, and reducing downtime and expenses.
- Transportation: Artificial intelligence and machine learning are being utilized to streamline logistics, route planning, and traffic control, boosting overall efficiency and lowering costs. They are also used to monitor the fleet and forecast repair needs, resulting in less downtime and lower expenses.
- AI and machine learning are being utilized in agriculture for precision farming, crop monitoring, and weather forecasting. They also aid in the optimization of irrigation and fertilization, the reduction of pesticide usage, and the improvement of agricultural yields.
In general, AI and ML may aid in the automation of repetitive operations, the processing of vast volumes of data, and the making of predictions and choices. This can result in increased efficiency, cost savings, and fresh insights in a variety of industries.
Hi,
I hope you are well.
There are different methods by using them it is possible to predict the response. For instance, we can use Machine Learning methods to predict seismic structural response. For this purpose, it is compulsory to have a reliable range of input data and output data. Then, using the regression analysis we can predict response. This is a functional procedure that is used in the literature. For Structural Engineering, this can be vital because it can decrease computational efforts considerably. Therefore, we won't have to use Finite Element programming (e.g., OpenSees) every single time with a huge volume of computational efforts.
I am looking for software that can predict responses in any field of expertise. If you have seen a kind of software that can predict a response within a second, and also, can decrease computational efforts exponentially in comparison with other methods, I would be grateful if you could share that with me.
Best regards,
Mohsen Masoomzadeh.
There are a lot of researchers who go by the book the right approach and write results, and observations in their field of work, proving the existing information or suggesting improvement in the experiment for better analysis and so on, very hard working but then there are other who are crazy thinkers always suggesting things with little backup from existing experiments or know facts, always radical in their understanding of results, and these people mostly get dismissed as blip by the first category of researchers.
So if I have to take your opinion who will you back for hitting gold one who is methodical and hardworking or who are crazy thinker?
Hello everyone!
I have started to work on my research project and I actively search for information on measuring electrification charges.
In the future I have to measure the charge of a tube with a fluid being pumped through it (a conductive tube connected to non conductive ones, the fluid is also non conductive, but will have some conductive additives).
I found a lot of theoretical works, but can't seems to find practical examples or equipment to use. The stuff I found are barebone depictions like: "There is a grounded tool installed along the pipe, that measures the charge", with no links to the source.
So I need some help to find methods and tools I can use to mesure the electrification charges.
What is difference in LORAWAN class A , B , C devices and what is spreading factor relation with time to air??
Dear all, I applied positive bias on gate, there is significant high leakage current on the transistor. However, when I applied negative bias on gate, the leakage current is insignificant. What can I infer from this?
Any researcher who is interested in working together in the field of Powers Electronics & Drives, Converter & Inverter Design, MPPT Techniques, Solar Photovoltaic Systems, Microgrid, EV Charging Stations. And also interested in publishing good quality paper. Kindly contact me. And also here Give your suggestion and feedback.
I will really appreciate it if somebody could share the software. My lab owns the stimulator but when we acquired it we didn't get the software nor the drivers. Grass doesn't exist anymore and "Natus" which is the company that bought it told me that "S88X" is a discontinued product and they do not longer provide support for it.
Its crucial for us to control the device from a PC.
Thanks in advance
I am a Research Student working on Beamforming in MATLAB. I want to generate a beam, track and investigate it. I want to send that beam in a specific rectangular region, pointing to a UE and then further track down the movement of the same.
I have been trying to get realtime ecg data from arduino using matlab.
I am able to visualise the real time data using this code.
Here the issue is I cannot get the filtered output at the same time as I am not aware of the fs.
Would like to know how we can process the signal realtime and plot the output.
I am attaching the result I am getting with this code (0 to 200)
The output is taken from arduino pin A0
clear
clc
close all
%get some user settings
%ledPin = 'D13'; %For blinking the led we should access this pin
%deltaT_blink = 0.5;
port = 'COM5';
board = 'Uno';
a = arduino(port,board); % we are creating an arduino object with this specific board and this specific port
%write a small for loop that flashes the LED on and off
% for k = 1:20
% %turn the arduino LED on
% a.writeDigitalPin(ledPin,1);
% pause(deltaT_blink*5);
% %turn the arduino LED off
% a.writeDigitalPin(ledPin,0);
% pause(deltaT_blink*2);
%
% end
init_time = 1;
x =0;
s=0;
f = 0;
tic
while(init_time<1000)
b = readVoltage(a,"A0");
x = [x,b];
% subplot(2,1,1)
plot(x)
xlim tight
% fs = 16; % Sample rate in Hz
% fc = [5 15]
% Passband frequency range in Hz
% [b1, a1] = butter(4, fc/(fs/2), 'bandpass');
% ecg_filtered = filter(b1, a1, x);
% subplot(2,1,2)
% plot(ecg_filtered)
% f1 = fft(x);
% s1 = spectrogram(x);
% subplot(3,1,2)
% f = [f,f1];
% plot(f)
% subplot(3,1,3)
% s = [s,s1];
% plot(s)
grid on
init_time = init_time+1;
drawnow
end
toc
Both SRAM and Flip-flop are volatile memory element. Is there any applications where both are used?
I am happy to share my new paper related to EV applications, which is currently an emerging area of research. I request everyone to please share my paper with your knows or groups.
Conference Paper Hybrid Energy Source Based BLDC Motor Drive for Electric Veh...
If you are willing to work in MPPT then I suggest you to follow this paper. This paper helps you to choose the best MPPT algorithm for your system.
cation/369600395_Comprehensive_Review_of_Conventional_and_Emerging_Maximum_Power_Point_Tracking_Algorithms_for_Uniformly_and_Partially_Shaded_Solar_Photovoltaic_Systems
Just a question i didn't have idea about and wanted to know as if we can generate electricity from cold waves then we can set power stations in polar regions.
When we Launch rocket to put our satellite in orbit , how it is put in orbit so accurately? Because as I know their are debries in Leo, Meo & Geo so how they find their way out by going through debries , are their any radars to detect the debries , how they avoid this debries ??
How do our Radars get the location of the Planes , jets or Missiles when they are moving ? like how does the stationory radar works?
Options for development of RES are based on FIT or TGC models of energy generation payment ?
What is better solution for country/investor? Why?
Any literature?
I understand trigger level as voltage level such that we acquire waveform just as the trigger level is reached.This helps to show the steady waveform. But I don't understand the role and meaning of trigger position.
Is this Correct That I can reduce Distrotions to Ideally zero and reduce noise upto a limit but no completly zero? right ,In digital communication
As till now after the matched filter or correlator we get a projection of vector and now with with Maxmimum liklehood AND with MAP criteria how we arrive to decission ?
What are the channel encoding techniques like LDPC in Digital communication?
what are the improvements and what are the tradeoffs ?
Am I right that isi is caused by multipath fading and
that should pass through same zero crossing ??
I hope this message finds you'll well. My name is Onyero Walter Ofuzim. I am reaching out to express my interest in collaborating in the field of Electrical/Electronic Engineering mainly in Control Systems Engineering, Dynamic Networks, Machine Learning, IoT, and/or Robotics.
I am deeply passionate about these areas and have been actively involved in research and projects related to them. I firmly believe that collaborating with others in this field will not only increase my chances of getting into a foreign-funded Masters or Ph.D. program, which is my ultimate goal but also help drive innovation and advancements in the field.
I am eager to share my ideas and knowledge and learn from others to contribute to the growth and development of these cutting-edge technologies. I am confident that my skills and experience will be a valuable asset to any team, and I look forward to the opportunity to work with anyone who will be nice to have me.
Thank you for considering my request for collaboration. I look forward to hearing about a possible invitation.
Feel free to explore my profile as I am optimizing it to make my chances high.
Dear Professor, Scientists and Technicians in the field :
I'm looking up on how to determine the Charging Current in a distribution (15, 25 or 35 kV) overhead power line.
These lines are Polyethylene-covered cables. But, since there is always a non cero Capacitance between Ground and the line, there always exists a Charging Current in the direction from the phase, to the Ground.
Does anyone know about the subject ?
How I can compute such result ?
Charging Current.
Best Regards!
Dear Professor, Scientists and Technicians in the field :
I'm trying to compute the Charging Current for a particular distribution Overhead line (25 or 35 kV).
And I found a paper where I found a couple of equations which allows you to calculate it.
However, in both of the equations you need to know the value of the Capacitance; between the line and the Ground
(in the attached image the equivalent electric circuit of this can be seen)
Two different circuits are shown here (a & b), because the paper where I took that, gives two different sub-methods to calculate the Charging Current of the line. Bith in both the Capacitance is needed.
I have no clue how to be able to figure out the value for the Capcitance.
Does anyone know about this subject ?
By the way, the formula for the Charging Current which appears in this paper is :
I = omega * C * [ V_phase-phase / sqrt(3) ]
I will really thank if someone can help
Regards !
PS. Paper attached too
I hope all of you doing well. My name is Mamunur Rashid, and I am a final-year student in Electrical & Electronic Engineering. I'm about to start my final year project/thesis. I'm struggling to find a novel/innovative topic to carry on this. My primary interests are Renewable Energy Systems, Smart Grid, Energy Management Systems etc. Is there anyone who can help me to find a suitable topic to start the review on. So I'm hoping for the best. Regards...
How to calculate the power dissipation for different switching activity in sequential elements?
I'm looking for a simple idea that can detect holes in a line of printed aluminum foils. I attempted to put an LED light in the back of the foil so that if a hole is detected, the light can be seen with human eyes. But what basic electrical sensor can detect this light and alert me?
I am trying to drive around 9 strain gauges with a 5V battery, after connecting the strain gauses to the battery, I found that the gauge outputs are very noisy. (since the strain gauges are used on moible platform, I can only use batteries rather than other power sourse with low noise)
To reduce the noise, I added a LM358N op amp as a voltage follower between the battery and the strain gagues. When the output pin of the op amp connects to no load, the output is 5V. However, when I connect that 5V output to the strain gauges, the output voltage of the op amp drops significantly as the number of the strain gauges increases. (even drops to less than 1V)
I think that the voltage drop may be caused by the low impedance of the strain gauges, which the LM358N can not handle. So my question is:
1. Are there any recommendations on op amps that can be used as voltage followers for low impedance outputs like strain gauges?
2. If proper op amps doesn't exist, what other components can I add in my circuit to eliminate or at least to reduce that voltage drop?
Looking forward to your suggestions and thank you in advance!
In terms of short circuit capability, IGBT used in UPS/motor drive/welding/white goods/PFC are required.
For Inductive Heating, there are mainly two topologies (shown attached): half-bridge and single-ended. Why SC capability is not required here?
Thank you in advance!
Hallo every one,
I did nanoidentation experiment :
1 photoresist with 3 different layer thicknesses.
My results show that the photoresist is harder when it has thicker layer..
I can't find the reason in the literature.
Can any one please explaine me why is it like that??
is there any literature for this?
best regards
chiko
Thermal management of electronics/PCB boards purely depends on the power it dissipates (component power dissipations). But the power dissipation values provided by the component suppliers are the maximum power dissipation and in realty on field the power dissipation is far from this max values. So, i am looking into other possible ways to determine this values, through physic or analytically maybe.
Any bit of information would be highly helpful !
Thanking in advance !!!
Regards,
Rajesh.
I am delivering power to my device using a VNA with frequency ranging from 300kHz to 8GHz. I am trying to figure out the current that passes through my sample, or DUT. I can set the output power of the VVNA and measure the S11. Here is my approach.
Since the total current (the sum of the incident and reflected waves) at the DUT can be expressed as:
I=V0/Z0 (1-Gamma)
then, use P0=I*V0, so current becomes
I=sqrt(P0*(1-Gamma)/Z0), where Gamma=10^(S11/20)
Is this approach current? Another method that I thought of is to first measure the DC resistance, R. Then, the current can be derived as:
I=sqrt(P0*(1-Gamma^2)/R).
Is any of these correct? Any help is much appreciated.
In a hypothetical situation where I have two wires, ones cross section is a cylinder, and the others a star. Both have the same cross section area, both have the same length. What are the differences in electrical properties ?
Are there any experiments done looking into this ?
Also what would happen if a wire had a conical shape, by length ?
I want to simulate a circuit having pin diode to verify switching function of PIN Diode in x-band. What are the softwares that i can use..?
It is a network of 30 earth pits. 3 sets of10 pits.
I have disconnected all the 3 sets. However, when I check for the resistance between the network of first 10 and that of the second set, I get 45ohms. Should it not show in k or M ohms as they are not galvanically coupled. One thing is for sure that they are not shorted as the resistance is as high as 40+
If I disconnected one pit from the remaining 9 in the first set, I get around 250ohms with multimeter.
I am trying to decouple all the 3 sets from each other but to no avail.
is it due to the high conductive compound that has gone into these pits?
Meanwhile, I'll try to explore more on this
Out of these 5 universities can you rate them from top to bottom which is best for coursework and research opportunities for Masters in Antenna Specialization.
Arizona State University, North Carolina State University, Virginia Tech, The Ohio State University, UT Dallas.
Hi,
I was working on a thesis project on a portable ECG device, I checked these
So it was basically biopotential->Amplifier->logging->displaying using Teensy(Programmable chip), Adafruit(Bluetooth Module), SPI LCD Screen, and resistors and capacitors.
I developed and assembled all except Teensy, adafruit, SPI LCD screen, as I don't have circuit on how to connect output to these 3 devices.
Can anyone share some other resources it would be very much valuable.
Thank You
case1 : when Radio frequency wave transmision line is loaded with matched impendace, then entire signal is taken by load without any reflections..
case 2: when a Radio frequency wave transmision line is loaded with short circuit, then entire signal is reflected back...
Now what happens when both the above cases are combined?
where will the signal go and how much will be the reflection coefficient?
will the matched impedance load get any signal?
I am trying to design a PIN Diode switch for a WR90 Rectangular waveguide ( X - Band) using HFSS software. I have learnt from some discussion that PIN Diode can be modelled using sheets and boundaries but how exactly that model i can use inside a waveguide as a switch? what are the parameters or extra devices i need to add? I couldn't find any open publications on PIN Diode switch in x-band rectangular waveguide Can someone recommend me some books or publications or blogs for better understanding of PIN Diode simulation in HFSS inside a waveguide.
We have chips on which there is tin, which disappears after a while. Tin is used on the chips to glue the heatsink.
What is your solution for chips that have lost their tin?
Due to the lack of poor heat transfer, we can not use silicone paste.
+1
Hi there,
I hope you are doing well.
Do you know, which camera is used recently for the GRENOUILLE technique in order to measure the pulse length of ultra-short pulses?
what features the camera should provide? Should it be fast or regular camera works as well?
This article names a camera but I am not sure it is used recently in experiments or it is out of date!
Attached is a document in this regard.
I appreciate your time and any feedback.
Best regards,
Aydin
I have just designed a fuzzy system, and now I want to redesign it based on the fractional order. However, I have no idea where to start from and what to do. Could you please tell me what I should do and mention any related sources to study?
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This questionnaire is part of the project aiming to analyze the transition from a linear economy to a circular economy, comparing developed and developing countries, at a macro level (nations, regions, cities).
The project is a partnership between the University of Brasilia (Brazil), coordinated by Professor Patricia Guarnieri and the University of Bologna (Italy), coordinated by Professor Augusto Bianchini.
Your participation is very important to us. Please share with your network!
Sincerely,
Patricia Guarnieri, Dr.
Professor and Researcher
Faculty of Economics, Business Administration, Accounting and Public Policies Management (FACE/UnB) - http://www.adm.unb.br/
University of Brasilia - UnB - http://www.unb.br/
ORCID : http://orcid.org/0000-0001-5298-5348
From Few Discussion i got to know about PIN Diode Equivalent RLC circuit. Then in hfss created 2 cylinder blocks both in contact to each other, then for one cylinder i gave inductance and for other i gave resistance and capacitance for Diode off condition. Similarly for DIode ON condition, for one cylinder i gave inductance and for other resistance. But it is not working as expected. Please need some help to design it.
I am trying to solve the differential equation. I was able to solve it when the function P is constant and independent of r and z. But I am not able to solve it further when P is a function of r and z or function of r only (IMAGE 1).
Any general solution for IMAGE 2?
Kindly help me with this. Thanks
Is it possible to replace a flyback transformer with a common transformer in a high voltage power supply by modifying the circuit? and if yes, what kind of modifications are needed?
I ask this because making a flyback is harder than making a common transformer.
I have updated my manuscript but its the third time the reviewer send me this comment again.
What are the probable redox reaction during cyclic voltammetry?
Could anyone guide me on this, please
Thanks, A lot in advance for your precious time.
- Journals ranking (Q1, Q2, Q3, Q4).
- Article Processing Charge (APC) <1500 USD.
Hello everybody,
Is it possible to control (adjust) the charge generated by the PC or laptop USB port?
I mean using for instance a matlab code
If you refer to the images attached of opamp, one is open loop config of opamp and the other is the closed loop config of opamp. In both of these equations, the formula to obtain output voltage remains the same including the common mode signal affects. However, the Adm term, called as the differential gain of opamp or the circuit, in open loop config refers to the open loop gain of opamp while the Adm term in the second circuit refers to the closed loop gain of opamp. The books I have referred are: Microelectronic Circuits (Seventh Edition) by Sedra Smith, and Op-Amps and Linear Integrated Circuits (Fourth Edition) by Ramakant A. Gayakwad.
Is the reason because the Adm and the Acm in the first circuit refer to the differential gain and the common mode gain of the circuit and the circuit is opamp itself so Adm and Acm are the differential gain and the common mode gain of the opamp itself? While in the second circuit, the Adm and the Acm are the differential mode gain and the common mode gain of the whole circuit? But I saw in Sedma Smith that for the second circuit, output voltage formula of opamp being used in terms of open loop gain without including the affect of internal common mode gain of opamp.
I have been studying quantization in context of Digital Image Processing. I referred to the 4th edition of the book titled "Digital Image Processing" by Rafael C. Gonzalez and Richard E. Woods.
In the book, the intensity quantization levels are defined as
L=2^k
where k is an integer.
Now the first thing that comes to my find is why is that the quantization levels should be integer multiple of two and why not just any integer in general.
A paragraph has been attached regarding this from the book.
Then I found a homework problem and its solution online which are both attached as images.
In the homework question, I believe n is used in place of k to calculate bits per pixel or bits per picture elements. While k was defined as integer in Gonzalez, here n comes out to be 3.32 bits per pixel (not an integer). Isn't it a contradiction?