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I am working on the project related to optofluidic sensors. I want to simulate a structure in "RSoft Beamprop" i had to draw defect region segment surrounding with 40 core and 40 cladding structures. 
its very difficult and time consuming to draw one segment and then make a copy and duplicate it every time. .
is there any efficient way to draw these 80 structure quickly to save time and make my design flexible. below i attach the segment pic which i should need to draw multiple times mean 80 times.
i shall be extremely thankful if someone helps me related to this. . 
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You can use photonic fiber and select 1D photonic, with 80 segment
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Hi RG,
I'm looking for a blood pressure device/module/kit which outputs raw data (serial or wireless, digital or analog). Usually, the information from these devices is on-screen only or, if Bluetooth, connected to an app that does not permit you to access the raw data.
I need to develop an instrument that measures the pressure data from the sphygmomanometer and processes it in a microcontroller to send it elsewhere.
I couldn't find this kind of solution anywhere. I'm already thinking of buying an analogical sphygmomanometer and hacking a pressure sensor in it. What do you think?
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To build blood pressure of a human you need to the cuff with an air pump to increase and decrease the pressure slowly to control the flow of the blood in the arm such that one can find the systolic blood pressure and the diastolic pressure.
Where the systolic pressure is the onset of blood flow after stopping it by higher pressure in the cuff. The diastolic pressure is the pressure at which one can no longer hear the pulses of the heart at the end of the pressure release stroke.
So you need a pressure measuring tool and you need a microphone to hear the pulse rate and the blood flow in the arm after the cuff away from the shoulder.
The relation between these two signals indicate the required points of the blood pressures.
You need to acquire the signal from these two sensors and process them to get the blood pressure points.
Best wishes
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The question is briefly related to electrical and core instrumentation. kindly guide me through this.
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I agree with Victor Edi Manqueros Aviles. And I think that we can generalize his answer to Sensors, Actuators, and Transducers.
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This figure is at page 390 of the book. I used Bride elements as R1=R2-2.2 K ohms. C=0.1 microF. R with C= 180 ohms. IC 741. Vcc +/- 12 V. I am trying to send two signals about 8.8 KHz and 16 KHz. Resistor in Amplifier 1 pin 2 and ground is 10 K. Checking results on Yokogawa DSO in FFT analyzer mode. But the circuit does not suppress the fundamental of 8.8 KHz sine wave. Both components are shown by DSO FFT analyzer.
Can anyone help.
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For problems more detailed explanation is avaliable at instrumentation by satish karna and
a k sawhney.
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Is it possible to use the same low level DC measuring methods such as electrometers , nanovoltmeters and picoammeters for low level AC measurements?
I'm using the following guide to learn about low level DC measuring methods.
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Absolutely agreed with the suggestions given by Islam Iskandarov. If you have low signal rf voltmeter then as suggested you can a small resistor in series with source and measure the RF voltage and calculate the amount of current as the resistor is known. Otherwise if rf voltmeter is not available use DC conversion approach and measure the voltage. Obviously the resistor should be selected in such a way that it generate voltage that should drive the DC convertor.
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Volatile sulphur compounds are measured til date while non volatile sulphur compounds may also contribute to halitosis
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Halimeter and oral chroma are electronic devices which You can use to detect volatile sulfur components in the expired air.
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This will help in detection of kidney diseases
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This is an interesting question, but it needs to be defined at what level of quantification or qualification should be addressed. If you want to evaluate very accurately, gas chromatography may be an option. However, there is a possibility of using a combination of sensors for specific gases and thus obtaining results at least interesting. It is not possible to say what precision is involved, but it is certainly possible to find references such as: https://jenslabs.com/2013/06/06/ketosense-an-arduino-based-ketosis-detector/
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I have noise in achieved signal and I don't know how eliminate noise from interested signal.
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Brother, Reza Karimzadeh do u filter the noise as pre-processing?? If you want to do it by Matlab, I can help you. Please let me know detail.
Regards
Md. Asadur Rahman
BME, KUET.
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I want to model the difference in temperature between an electronic instrument surface and the ambient air. I used a linear multiple step-wise regression model with six variables as the potential predictors: net radiation, incoming shortwave (solar) radiation, incoming longwave radiation, horizontal wind speed, air temperature, water vapor density.
The significant curve-like trend in the scater plot of the modeled and measured temperature difference indicated that the linear model form was likely wrong.
But, if we ignore the interactions between the cilmatic variables, which variable should have a non-linear influence on the heating or cooling of the instrument surface compared with the ambient air? The wind speed? And also the water vapor density?
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Oh, missed the air temperature position.
Anyway, the turbulence vs. air speed problem holds.
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when to use this current feedback opamp?
what is the advantage and disadvantage of both types amplifiers?
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Very basic considerations, see appendix below
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This question might seem personal and of course, it is, but many of my friends are facing this problem.
I am a sophomore student and I want to do research in the field of electrical and electronic engineering. I am not quite sure about the specific field but I am finding interest in power electronics, embedded circuit and integrated circuits. But I want to know why should I be doing higher studies and research in these fields? Can somebody please tell me the future aspects of these branches? It would be very helpful for us.
Thank you in advance.
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It is extremely pleasant to see that students now have started becoming concerned about what exactly their interest in EE is ! There are two questions in your message:
i) Why should one go for higher studies/research in his/her area of interest? Advancement in Technology is a never-ending process particularly from applications point of view. So, we see a rapid change in the way how technology is making our life easier. All this fruits are as a result of envisaging and realizing novel solutions. So, to summarize:
Higher education -> (should lead to) Enhancing research expertise -> (which should ultimately map to) -> Using Technology for human welfare
ii) Future aspects of these (mentioned) branches?                                                  IMHO, future of ANY (and EVERY) branch is bright iff we have genuine interest in that particular branch. Why? Because, if I have original interest in a particular domain, I would be able to think beyond constraints. The more interest I have in an area, the broader the horizon is. Just my thoughts.
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Which structure of the transistor is the most sensitive to pressure? A vertical NPN transistor and a vertical/lateral PNP transistor are considered. Which structure of the transistor will be the least sensitive to temperature and will have the lowest noise component of the output signal?
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Dear Michael,
welcome,
In metallic semiconductors, the pressure causes strains in the material which leads to change in the energy band structure specially the energy gap. The energy gap  decreases with pressure. As a CONSEQUENCE, the the intrinsic concentration increases and the minority carrier current. This means the injection increases as the  pressure increases. 
Applying the pressure on vertical transistor will decrease the energy gap of the layers underlying the pressure. That is the emitter, the base and the collector layer. So, the injection current in both directions(sises) of the emitter-base increases. The effect on the collector will be neglected since it is reverse biased.
 In case of the lateral transistor applying the pressure on the base region will enhance only the forward current injection from the emitter to the base. This effect is much like the strained bipolar transistor of the silicon germanide transistors.
This my expectations. It remains to verify it with elaborated analysis or experimental evidence.
Best wishes
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Recently I am trying to reverse engineering circuit of the torque sensor (attached pictures), that compromises of two TI op-amp, two regulators, AD685 for compatibility with HART protocol. But it's a sort of very time consuming and I have always been willing  to learn how to design these kinds of analog circuits. I really appreciate if anyone may show me a schematic circuit of this type of circuits. This will be a big help to me. 
Thank you all 
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align your strain gauges as shown in the figure and make Wheatstone bridge of it, followed by Instrumentation amplifier, with required gain. you will be able to do torque measurement, be careful while selecting and Mounting Strain gauges. reproducibility and repeat-ability depends completely on the mounting methods....all the best!
attached is the signal conditioning schematic with 741 opamp. there are also ICs available in market which can reduce component density on board.
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Electropneumatic Signal Converter is used for converting direct current signal into standard linear pneumatic signal for process control system applications. It is used for converting control signal 4-20 mA or 0-20 mA etc. coming from Electronic Controllers etc. into a linear 3-15 psi or 0.2-1 kg/cm² pneumatic signal for operation of control valves and dampers etc.
Please explain the working of it and if possible add a circuit diagram also.
Thank You.
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The concept of converting electric current into force and then pressure is by means of the electromagnetic.It is so one can make a DC magnet by flowing the current into a an electric coil. Then this magnet is made to move a piece of iron . The piece of the iron is connected to spring in one end while the spring is fixed in the other end.  the piece of iron can be driven by the magnetic field of the electric current to  actuate a plunger of a valve. The other method one can exploit the principle of the DC motor where one has a permanence  magnet and then push the current in a coil in the magnetic field of the permanent, this coil is made to deflect against the restoring force of a spring. This deflection can be used to actuate a plunger.
Simply one exploits the electromagnetic effects to build current to force transducers for mechanical actuation.
Best wishes
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In few recorders we not use transducers and in few of them we use. So, i want to know that what are the advantages or disadvantages.
Please comment related to details of sensors also which is used in a hybrid recorders.
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First the question is not complete and clear. Which type of recorder you are talking about? Mechanical, Electronic (Analog or Digital), or Magnetic etc.
Any recorder record a variable quantity. May be physical- temperature, pressure, humidity, weight, speed, acceleration, voltage, current, power etc. etc. Now these physical quantities need to be converted to another physical quantity say mechanical movement, or voltage or current depending upon the type of recorder. This conversion of one physical quantity to other takes place through a mechanism or a device called transducer. Simple microphone is a transducer. It converts air pressure into equivalent varying voltages. Speaker is a transducer that converts varying voltages at its input into equivalent  varying air pressure.
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It was very interesting to me to discuss how to investigate circuit elements (e.g., semiconductor devices) in the simplest, elegant and clever way...
...but even more interesting to me is to build circuit systems with these elements and discuss their behavior there...
Basic circuitry is my favorite discipline because it allows me to reveal in the best way the philosophy of electronic circuits. For many years, I dedicate the first lab of this discipline to passive resistive circuits because my concept of electronic circuits is that, in many cases, they are just improved passive circuits. Moreover, equivalent passive resistive circuits may be used to represent, in an attractive way, the operation of the more complex active electronic circuits.
Encouraged and inspired by the successful implementation of the labs on Semiconductor devices as free experiments on prototyping boards during the previous semester, I decided to do the same in the course of Basic circuitry this semester. But where to start? What is the simplest and, at the same time, most productive passive device  - the resistor, the voltage divider or something else? Eventually, I chose the potentiometer...
At first glance, this simple device does not deserve any attention, so you can not find it in the most electronics books. But I have long ago fascinated by its unique properties that made me excited to create, together with my students, the Wikibooks story below:
So, I began to prepare the equipment for implementation of the so unusual lab devoted, imagine, only to the simple potentiometer! I was already convinced how useful floating power supplies (adapters) are; so I prepared a set of two pairs of such devices - DC (12V/1A) and AC (24V/0.5A), with suitable "needle" ends, for each of the four working places. Also, I prepared a sufficient number of multimeters with the same "needle" probes, oscilloscopes with handmade "solid wire" probes, solderless prototyping boards... and, of course, a sufficient number:) of 1k potentiometers...
But my efforts did not go in vain, because it really was an incredible laboratory exercise, where my students were able to learn about important circuit concepts and devices:
This made me offer you to discuss here all these incarnations of the ubiquitous potentiometer. So, what are all these very important circuit concepts, devices and circuits represented by the mere potentiometer?
(By the way, my students managed to burn only one potentiometer although they were working hard in this direction:)
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The summer semester already ends... and also the course of Basic circuits... and it is time to say goodbye to my favorites...
But is there something more satisfying for a teacher than the success of his/her students? So I am very happy that two of them - Georgi Velev and Evgeni Sabev, participated successfully in a Space Apps Challenge 2016 of NASA with their proect Adept... and reached the final... In the laboratory we discussed the circuit of the strain gauge bridge and the instrumentation amplifier.
A year ago, their team achieved the same success with the project Valkyrie. Their team leader Martin Kuvandzhiev was then my student...
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Biomedical, Medical, Electrical, Electronics, Instrumentation, Medical Device, Embedded Systems
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I think you can use EEG technology as emotive kit
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Instrumentation or Electrical or Electronics 
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Hi
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I am trying out a CMOS rectifier. I did built a diode connected half wave rectifier and it works fine.
The doubt which I am getting now is, how important is the bulk connection in diode connected transistor (PMOS).
Consider a PMOS with Gate-drain (GD) connected, and the bulk connected to source terminal (SB). Now the question is which of these connection form the P and N terminal of the diode and how is it determined.
Which junction in transistor, the diode characteristic is used. Is it drain-bulk, source-bulk of gatedrain-source junction.
Can anyone brief on it ?
What is the Best way to connect the bulk in diode connected PMOS for rectifier application? - ResearchGate. Available from: https://www.researchgate.net/post/what_is_the_Best_way_to_connect_the_bulk_in_diode_connected_PMOS_for_rectifier_application [accessed Feb 8, 2016].
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I guess you are working on a classical twin-well CMOS technology where the PMOS is made in an N-well and this is embedde in a P-type substrate. If you use the PMOS as a pseudo-diode, the Gate must be connected to the Drain of the PMOS. The Gate/Drain is then the cathode of your pseudo-diode and the Source is the anode.
The problem with the N-well Bulk of the PMOS is that this Bulk is also connected to both Drain and Source by a real P/N junction diode. In order to prevent these real diodes from becoming forward biased (which can provoke lacth-up) The Bulk must in all circumstances remain at a higher voltage than both the Drain and the Source voltage minus a diode voltage.
In forward bias (conducting pseudo-diode) connecting the Bulk to the Source is OK since the Drain is then at a lower voltage than the Source.
In Reverse bias however (blocking pseudo-diode), the Drain can go higher than the Source and the Bulk can no longer be connected to the Source since then the real Drain/Bulk junction diode becomes forward.
Hence, the Bulk of the PMOS pseudo-diode is normally connected to the highest (supply) voltage or at least to a voltage higher than the highest Drain or Source voltage. This is safe but not ideal since the bulk-effect will increase the threshold voltage of the PMOS.
This is the case for classical twin-well technologies and also for triple-well technologies. It can be different for SOI technologies.
Note that some SPICE models do not include the real S/Bulk and D/Bulk diodes in the transistor model and most do not include the Bulk/Substrate diodes.
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As a rule, BJT output characteristics are presented as a family of particular characteristics representing the function of the collector current IC of the collector-emitter voltage VCE while the base current IB is kept constant as a parameter. Maybe this two-dimensional way of presentation is widely used since it is convenient for printing on paper...
When we automatically measure and plot BJT output characteristics by a computer (even the primary Apple II), we have the unique chance to present them in a more attractive three-dimensional way. Now the collector current is a function of two variables - the collector-emitter voltage and the base current; IC = f(VCE, IB). The image on the screen is a surface, in which the particular characteristics IC = f(VCE) are represented by separate vertical sections of this surface.
I implemented this attractive experiment in the early 90's when I was trying to make vocational teachers in Bulgarian carry out real computer experiments in the semiconductor laboratory... but they proved unprepared for this... A program written on MLBASIC (an assembler extension of the embedded interpretator) was controlling an Apple computer equipped with an analog periphery - 4 DACs, 4 ADCs, power voltage-to-current and current-to-voltage converters (described, regretfully only in Bulgarian, in the attached link after the pictures below).
It is amazing that then I had no idea that I will reproduce this attractive experiment with my students whole 25 years later...  and really I will start doing it today... I made a "dress rehearsal" of the "show" at the university on Saturday evening. It was too late and dark in the laboratory... so movies I made were very poor (there was a mistake in the camera settings)...
(Measuring of a 3-dimensional transistor output characteristic by MICROLAB)
(Plotting a 3-dimensional transistor output characteristic on the screen)
(Temperature influence)
This question is closely related to the questions below:
It would be interesting for me to see what you think about this way of presentation. Is it the actual output transistor characteristic or only another attractive presentation?
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Dear Cyril,
Any representation has its objectives.
Let us analyse the two figures representing the same data. That is the transistor curves.
The transistor i-v characteristics can be expressed formally by the function:
IC= f( VCE , IB)
From the two port notation of the transistor, the output port parameters are IC and VCE.
IB represents  the  effect of the input port current on the collector current. 
Accordingly, to represent the output transistor characteristics on a two dimensional graph one has to choose VCE as a continuous variable and IB as a discrete variable having with proper steps. It is so that we sample the base current. This is the conventional way where the value of the base current is written on it as a label for the figure. Such transistor iv representation is used to solve graphically the tranistor circuit. We all know the concept of the load line and the DC operating point. so this presentation is characterized by its simplicity and ease of use.
Now it is to be compared by the three dimensional representation of the same transistor curves that you propose.
It is so that you add a third axes to represent the base current and then you have to draw the transistor curve at the new base current in an other plane shifted by the magnitude of the base current. So, there is no need to label the curve. This is the single benefit from the three dimensional representation. Which means that you use a different page to draw an i-v curve.
This new representation will complicate the concept of the graphical solution.
So, the only benefit is  not to label the i-v curves with the base current but with a more complicated solution.
I do not see any advantage from the three dimensional representation of the the output tranistor curves. In the opposite it brings unneeded complications.
This is my opinion on your proposal.
Best regard  
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We are working on induction heating and we are having trouble to measure the high frequency magnetic field strength (about 1 kA/m)? We have the coil design (nos. of turns and dia) and we know the current. From these quantities, we are using solenoid equation to theoretically estimate the magnetic field value.
But is there any instrument to measure the field directly at these high frequency. Normal gaussmeter is not working. Moreover, any metallic probe may get heated up extremely fast due to magnetic induction.  
Any help is well appreciated. Advanced thank you.
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Yes, a pick up coil is the way to go, attached to an oscilloscope.  To calibrate it, you can run an alternating current of known amplitude through a larger coil with a known diameter and number of turns, and then measure the voltage response in your pick up coil (which you would place inside the larger coil with axes parallel).  You can calculate the magnetic field produced by the large coil of known geometry and known alternating current.  Choose a few different alternating current values for the large coil and measure the resulting voltage in the pickup coil each time.  Then you can plot pick up coil voltage vs B field in large coil.  Now you have a calibration curve for the pick up coil.  Now you can measure an alternating  B-field of unknown amplitude.  Remember to orient the pick up coil to obtain the maximum voltage in the unknown field to get the full amplitude of the unknown field.  In summary you need a pick up coil, an oscilloscope with a bandwidth of at least 126 kHz, a source of alternating current, a way to measure the alternating current, and a large coil to generate a test field.  Good luck!
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This is challenging as we might loose contact in some spots as curling happens due to thermal gradient.
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Hi Abolfazl,
The answers depend greatly on whether the concrete slab will be removed after a while, or that it stays in place, and you have only one chance of placing the sensors.
In the first case you could apply pressure sensitive foil that contains tiny ink capsules that release upon pressure, to get a pressure image.
For permanent installation with real-time readout on a large amount of places, you might apply numerous sensors distributed along an optical fiber, based upon Fiber Bragg Gratings (FBGs). These are used for monitoring all kind of large structures. FBG based sensors can be used for a wide variety of parameters, and you can even mix parameters along a fiber. Lun Cheng from TNO is a world-renowned expert on these sensors.
Kind regards, Fokko Wieringa
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hai sir this is  guru.... i'm doing simple task with labview ...now i'm having some questions about labview interfacing
 
1)can we display  labview software outputs (Like signal generator output signals) in external instruments of signal genertors (agilent and R&S). how??????
2)how labview software control external instruements ???? and is it requires any instrument drivers for communication...please specify the names of instrument drivers
please help me sir
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Via LabVIEW/Menu/Help/Find instruments drivers you can download driver for your signal generator. Use Keysight as manufacturer when searching. With the driver a project including sample applications will be installed as well. Based on them you will success.
For the scope you can find the driver the same way.
For help in downloading and installing the drivers see the videos linked below.
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Standard uncertainty is the estimated standard deviation of measured values. However, the dispersions of electronic components values are specified by companies as tolerances in datasheets and do not bring information about statistics (moments, PDF) . How their uncertainties can be modeled?
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The confidence level used is in general between 95%-99.75% (±1.96σ - ±3σ).
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I'm a student in university and in this year I'm studying over regenerative braking system. I am interested different articles about that. Specifically in the regenerative braking what articles are used for different switching? For example, when a Phase is positive and b phase is negative, switching is a_low, but in the other article switching is b_low. Which switching do you think I should use for that? By the way, I formed the system in matkab/simulink, but I didn't divert the current toward the battery. I can send the simulation. Could you help me please?
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You can get the similar or apropriate answer by searching the keyword in the GOOGLE SCHOLAR page. Usually you will get the first paper similar to your keyword.
From my experience, this way will help you a lot. If you still have a problem, do not hasitate to let me know.
Kind regards, Dr ZOL BAHRI - Universiti Malaysia Perlis, MALAYSIA
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A wind blade consists of steel chassis and composite laminae as outer surface. 
I want to make bending stress on the blade. It fixed from end as cantilever. 
I will put strain gauge rosette near the fixation end on the composite laminae as known to have maximum bending stress. 
I want to calculate stress values from the strain readings. 
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Hello Ahmed.
If you look at the rosettes, these are primarily used for measuring dual (or multi-axis) strains. It is actually  a combination of commonly used strain gauges usually arranged in X-Y (90 degrees) orientation to determine the stress/strain in these two (or more) directions.
I would suggest to go for a Torsional gauge (or torsion strain gauges) which has some slanted pattern (unlike linear patterns in the commonly used strain gauges) for your applications. I believe you want to study or measure the bending of a the blade if it is rotated (bent, not the actual rotation) due to wind pressure.
Hope this will be useful to you. Best luck!
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The majority of the literature related to low-frequency impedance spectroscopy recommend the use of four-electrode (4T/4E) measurement systems in order to "eliminate" the electrode polarization (EP) effect.
Anyway, every time I read an empirical work paper describing the use of 4T-based measurement in biological and soil studies, the platinized electrodes (typically platinum-black coated) show up.
It seems to me that the potential probes may still be impacted by EP and the platinization is a way to mitigate this. Is that right? If so, it is my opinion that the term "EP elimination" cannot be used (rather "EP mitigation") without a proper characterization of the effect of the electrodes material in 4T systems.
Unfortunately, I could not find specific explanations for my question at the original 4T works (H.P. Schwan and others).
My goal is to find (or develop) a step-by-step guide related to the use of non-commercial 4T electrodes and soil dielectric measurements. I am fine in terms of electronic instrumentation for this goal, but the missing aspect is related to the soil probes themselves.  
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You are right. Platinized platinum is used in 4-electrode measurements, for example in myocardial impedance studies, because it is a simple way to increase the true surface area of the electrodes and to reduce the electrode polarization compared to shiny platinum. Also, if I remember correctly, when combined with iridium, the coating increases the stiffness of the electrode, which is useful for penetrating tissue using needle electrodes. Another reason is biocompatibility. Anyway, the electrode impedance will be different from zero (especially noticeable at low frequencies) and, therefore, the word "mitigation" might be more appropriate. If the impedance electrode obtained using the 4-electrode method is still unacceptable, a more sophisticated approach can be implemented with a 5-electrode setup, where the impedance under test is obtained from a two-step 4-electrode measurement. In this case, it would be equivalent to performing a calibration in situ. 
Take a look at the following work, it may be helpful.
McAdams et al., Effect of surface topography on the electrode-electrolye interface impedance. The high frequency, small signal, interface impedance - A review. Surface topography, 2, 107-122, 1989.
McAdams, E T and Jossinet J, The detection of the onset of electrode-electrolyte interface impedance nonlinearity: a theoretical study, IEEE Trans Biomed Eng, 41(5), 498-500, 1994.
Regards
Benjamin
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Hi ,all.
      I want to process a 1D signal using  dilation of mathematical morphology.  I know the function imdilate in matlab can do it. However, you know, the 1D signal is different to  the image.  So someone said : the structuring element must be a linear  flat with all 1 ,like [1 1 1 1....], if not all 1 ,like[ 1 1 0 1] or nonflat ,the function imdilate will be invalid. Is it right?  Thank you very much.
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Yes you are right you can simply use imdilate:
str = strel('line', 3, 0); % make structuring element (a line)
ke = str.getnhood % just print the structuring element
line = [ 1 1 1 1 0 0 0 1 1 0 1 1 1 1 1 1 0 0 1 1 1 1 1 1 0 1 1 ]; % create a 1D data
linedilate = imdilate( line, str); % dilate the 1D data using the defined str. element
linedilate % print the result
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Dear all,
Are there any alternative treatments to avoid using the mixture H2O:H2O2:NH4OH, in the steps of Si wafer cleaning (RCA SC-1: Removal of Residual Organic Films, Certain Metals, and Particles) ?
Thank you for your help
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several alternatives have been developed, see chap.1 by W.Kern (the inventor of the RCA-clean including SC-1) in the 2nd ed. of the Handbook of Silicon Wafer Cleaning Technology (William Andrew, 2008). One is the so-called imec clean (after the institute where it was invented), another is the so-called SCROD clean (for single-wafer spin cleaning with repetitive use of ozonated water and dilute hydrogen fluoride). SC-1 main purpose is to remove contaminant particles by an under-etch and lift-off process, etching the surface chemical oxide and relying on the high pH to create opposite surface charges. In these 2 alternatives the oxide is etched using dilute HF. The imec clean is a 2 steps process, starting with a SPM (sulfuric peroxide mixture) to remove organic contamination, followed by a dilute HF to etch the surface oxide and remove particles (and also metallic contamination). HCl can be added to HF to prevent outplating of metals such as Cu on the bare Si surface. The surface finish is hydrophobic. An ozone rinse is typically used if an hydrophilic surface finish is wanted. The SCROD clean functions by alternately applying ozonated water and dilute HF onto a wafer surface for a few seconds, a cycle that can be repeated as many times as necessary until the surface attains the required level of cleanliness (see e.g. http://micromagazine.fabtech.org/archive/03/01/hattori.html).
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I want to measure deflection of cantilever beam in micrometers. 
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your measurable deflection is too small so, i suggest you to use optical sensing method. optical triangulation method based on position sensitive detector (PSD) is the best approach for that kind of deflection & displacement measurement.
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A 900w (100A, 90V DC) power supply with a sputtering of atoms is transferred from a material transfer to other substrate material, and the other material is used to mix with them. Through a magentron sputtering gun, is there any power received for other electronic equipment to synchronize it?
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in a system we have synchronize with magentron gun as well as 900W arc power supply so when we applied arcing then is there any possibility of power receiving to magentron gun
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Except software manuals and specific application note, I do not know where to start to study these techniques. Can someone help me? Many thanks in advance.
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I'll also recommend Exploring Scanning probe microscopy with Mathematica by Dror Sarid, it is old comparing with two books mentioned above, but it contains some basics of such measurements.
It also depends on type of the device you have, new digital electronics (Solver next or new controllers for Integras) capable of single pass Kelvin probe/Capacitance contrast with height measurements, old analog can do only two-pass measurements. There also were Magonov webinars recorded about electrical measurements with NTMDT devices.
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There is my Basic Am modulator design with Labview in youtube link.
I modulate signal which is simulated, but I want to modulate my voice or any mp3 or mp4 or wav file in Labview . How can I do this ? Is there any way ?
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You can also try to implement an AM modulator using single mathematical operations. The goal is about to build the AM signal, given by:
XAM(t) = A(1+mx(t))Cos wct
Where m is the modulation index, wc is the carrier frequency, x(t) is the message and A is the carrier amplitude.
Now, this scheme works well with lowpass signals (like voice) but i'm not really sure whether this works with an audio file (mp3), so you probably need to check its frequency content.
Best regards!
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These is for making a input to the control board to set up the current value according to that it will the maximum current .
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I recommend you the ISO124 from BB, I have used this in the pass with good results,
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Normally we measure power of high frequency signal using power sensor which convert the power of signal to power around its DC component then monitored by power meters .
Now , is it valid if we use the system of current probe +digital scope +power module?
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Hello Ali,
I think, it is best to get the calibration done for whatever method you adopt and then validate your test results.
When you are involving many individual instruments - as your case is - current probe+ digital scope + power module, you will need to calibrate or atleast provide traceability to some standards for all the instruments.
I do not know what power level you are working with but there are some specialized chips available that can be used for RF power monitoring purposes. I am currently using AD8307 from Analog Devices for <10W RF power up to 100MHz FM band. The literature provides more information with various application circuits.
The output from this chip is a calibrated DC voltage (approximately 25mV/dB). As this is a factory calibrated output, one only needs to validate this against some standard power levels.
There are also some other chips targeted for Cellphone applications for up to 2GHz. Hope that these suits your application.
Hope this info helps you!
Thanks
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We can enlarge the powerful idea of the “ideal” op-amp ammeter already discussed in the question below by replacing the movement with other current-driven loads (2-terminal elements like LEDs, solenoids, motors, rechargeable batteries, etc.)
Regardless of the device, the op-amp will always do the same – it will make its output voltage equal to the voltage drop across the corresponding device. As a result, the device “disappears” and the input current source “sees” just a “piece of wire”. We can think of this “wire” as of a kind of artificial “active superconductor” with zero resistance. We can also look at this phenomenon (aka “virtual ground”) from another perspective - shorting the input imperfect current source, we actually have provided it with ideal working conditions and it has began behaving as a perfect current source... and this is one of the possible ways of making perfect current sources
But all these op-circuits have no (electrical) output; their outputs are light (LED), displacement (solenoids, motors...) or none (rechargeable batteries). More frequently, we need circuits (converters) with electrical inputs and outputs; maybe the transimpedance amplifier is the most typical representative of this class of op-amp circuits. So, the question is, “Where do we take an electrical output from?”
Let’s solve this problem by building the ubiquitous transimpedance amplifier. Although we can do it by adding only one additional step to the 4-step ammeter building scenario, let’s for completeness do it from the very beginning.
1. NO PROBLEM. Imagine a current I = V/R flows in the simple Ohm's circuit... and it really is I = V/R... but we want to see if this is true. There is only one way to do it - by measuring the current.
2. THE PROBLEM. Contemporary instruments measure voltages; so, if we want to measure a current, we have to convert it into a voltage. For this purpose, we break the loop, connect a resistor and measure the voltage drop across it... but a problem appears. The voltage drop is desired for us and we want to be as much as possible higher to obtain a maximum "gain" (a minimum discrete error of the next ADC); so we need a maximum resistance. But, at the same time, this voltage drop disturbs the input (imperfect) current source; so to obtain a minimum error, we have to keep minimum resistance. If we measured the current of a perfect current source, there was no problem since the source would compensate the "undesired" voltage drop by increasing its own internal voltage... but in our case the source is imperfect. What do we do then?
3. THE REMEDY. We already know the remedy (from the question about the ammeter) - we can remove the resistance by an equal “anti-resistance”... or, in other words, the voltage drop by an equal (electromotive) "anti-voltage"... So, we add a humble variable voltage source in series with the resistor and adjust its voltage equal to the adverse voltage drop. As a result, the voltage drop and respectively the resistance as though disappear... and the whole circuit looks as a “piece of wire” to the input source. The additional compensation source actually "helps" the input excitation voltage source, which creates the input current (note that the two voltage sources are connected in series, in one and the same direction "- +, - +" so that their voltages are added).
4. THE OUTPUT. But where do we take the output from? Actually, the voltage drop across the resistor exists but it is not a good idea to use it as a circuit output (first, it is “floating”; second, the next stage may disturb it). Then? The clever idea is to use the compensating (op-amp) voltage as a "mirror" output (just like in life when we estimate indirectly some positive quantity by an equivalent negative "antiquantity"). All the circuits with parallel negative feedback (i.e., all the inverting op-amp circuits) exploit this idea. The advantages: first, the load is grounded; second, it consumes energy from the compensating voltage source instead from the input source (so, the load can be low-resistive enough). A disadvantage may be the inverted output...
5. THE IMPLEMENTATION. Finally, we have just to replace the manual "op-amp" by a real one and will obtain the so desired “ideal” current-to-voltage converter (transimpedance amplifier) well known from the classic electronics books.
This story about the transimpedance amplifier was the continuation of the previous story about the simpler op-amp ammeter. What do you think about it? Have you ever seen such an explanation before? Is it reliable? Is it useful for understanding compared with the conventional virtual ground explanation? If you like it, visit the links below and enjoy.
And yet, is there any connection between the humble resistor and the transimpedance amplifier? What does the op-amp really do in this electronic circuit? Can we say the op-amp is a "negative resistor" and the transimpedance amplifier is a "zero resistor"? Or, even more figuratively, the transimpedance amplifier is a "neutralized positive resistor" (R - R = 0)? If so, it would be a good prelude to the subject of negative resistor... and we can continue this story...
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Yes - I do. Nice analogy - congratulations.
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How can we design a simple lock-in-amplifier?
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A lock in amplifier (phase-sensitive detector) is an electronic circuit used for discriminating noise component in a signal. A lock-in-amplifier internal circuity composed of four operative stages, a modulator, selective amplifier, synchronous demodulation, and low pass filter . the lock-in amplifier perform the later three operative stage. the following link give details of the lock in amplifier :
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I have 2 winding transformer whose primary is fed from two phases out of three phases giving the primary side a 415 volts. The secondary voltage is 220V, but each terminal to ground voltage is 110v each. Now I have my miliamperes current output of various electronic instruments is fluctuating. Is it due to the switching surges? how can I get rid of this problem?
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I wanted to say that I am using this step down transformer to power my 220V instruments like pressure transmitters, level transmitters, PLC , etc. and ot as CT/PT. I am facing a problem of fluctuating output miliampers in these instruments. Can you please give solution to this problem.
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If we have to find the speed of sound in any material measuring sound vibrations at different points in the sample, what kind of piezoelectric sensors which have high sensitivity would be useful?
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Experimentalists state that to generate and detect acoustic waves in the piezoelectromagnetics (PEM), also known as the magneto-electro-elastic materials, is more preferable with such non-contact method as the electromagnetic acoustic transducer (EMATs). Also, such the two-phase materials possessing both the piezolelectric (PE),and piezomagnetic (PM) effects as well as the magnetoelectric effect can be used for smart materials. Anyway, PEMs can be used instead of PE and or PM. PEMs can give more possibilities for sensors, see my books for the non-dispersive waves' propagation in the PEMs and I have also just written one book on the thirty two new dispersive SH-waves' propagation in PEM plates. It is stated and well-known that SH-waves can possess a larger sensitivity.