Accuracy of the POWER function

Similar Questions

• The power spectral density function counts inaccurate amplitude caused by the window function?

  I'm new to this forum, so please let me know if this would correspond better to a different discussion forum.

  Here's the question:

  I would like to know if the power spectral density function ("FFT PSD for 1 Channel.vi") automatically compensates for the loss of the amplitude of entry caused by the window function.  In other words, is a specific window correction factor applied within the PSD vi or do I apply manually?

  Details of the background:

  I tried to answer the question myself by generating a sine wave sampling, it as it is periodic in record time (i.e. 0 to each end of recording time).  The frequency of the sine wave was such that the frequency would exactly correspond to a spectral line in the PSD.  Then I generated the PSD of the sine wave twice: once using a Hanning window and once using a rectangular window (not on average in both cases).  The rectangular extent of the PSD with windows to the frequency of the sine wave is 1.5 times the size of the PSD with a Hanning window applied.

  The experience above indicated to me that a manual setting of the PSD output for the function of window was necessary, however, I repeated the above experiment using random vibration data and does not clear 1.5 x factor.  I have also been informed by his colleagues that the PSD should set for the window function.

  Thank you for your comments.

  Spectral leakage.  When you use a finished sample data from the spectrum resulting is the convolution of the spectrum of the signal as if it extended indefinitely in time with the spectrum of the window.  Even if you do not use a window function, you actually have a rectangular window the same width as the sample size.

  Draw out of the VI PSD with all style of trace to show points to the data points. Turn off Auto scale on the X axis, and expand the graph around your pic. Look at the results of different windows.  In any case, there are several values non-null.  With actual sampled data of limited duration, you will never get the idealized line spectrum.

  If summarize you the output spectral value remains close to 3.2 for all windows.

  Lynn

• The Hold function should disable the power button?

  I activated the Hold function on my 8 GB Clip + by pressing the home button.  However, I was still able to turn off the drive by pressing the power button.  This is how it is supposed to be?  No other buttons work but the power button still worked on "hold".  I have read the pdf of Sansa manual and searched the forums but cannot find anything on this topic.  Apologies if it's already been addressed.  Thank you.

  The power button is seized of the primary key for the Clip +, so it will always have priority.  It is "wired" into the device.  Note that the power button which will be held for a while for the power control.

  On the e200 series, the main control is the menu button of the switch on the Clip (basic), it is the slider switch contact, as on the Sansa Fuze / power.

  Bob

• User of the RPD power function

  Hello

  I'm developing this formula in OBIEE using the power excel function.

  = ((1+11.9/100)^-0.25)*(Auth Total deles de intérêts + frais Total de Auth) ))

  = ((1 + 0,119) ^-0,25) * (Auth Total interest + Auth Total expenses)

  Can someone please help to get the right syntax. I don't know how to apply for a power of-0,25.

  
  

  Thank you
  

  Hello

  The RPD, you can use power function (it is in mathematical functions).

  For example:

  Power((1+11.9/100),-0.25) * (Auth Total interest + Auth Total expenses)

• Satellite A660 - meter problem and the function of the power keys do not work

  Hi all

  The drop down menu that appears when I pressed on the FN key disappeared as well as when I turn of the backlit using FN + Z, light under the keyboard just turns off but the light beneath logo buttons on it near the power buttons and satellite does not turn off. How can I solve this?

  The computer displays the electric meter error and eco top near power button never lights energy saving does not work. I tried to reinstall the driver of programs/toshiba eco, but it says BIOS not supported.

  Before you try to reinstall the VAP, try to restart the Flash Cards Support utility. Utility support card Flash controls the FN keys and you can restart it in all programs-> Toshiba-> restart Flash Cards

• Question about the accuracy of the Total remaining time for battery in Power Meter

  Mr President.

  I checked several laptops that are of the same model, one of them cannot display "Total time remaining" in the power meter. Even other laptops may display, but the values are equivocal. Sometimes the 'remaining power' is 80%, but 'Total remaining time' is 1H20Mins. And sometimes, the "remaining power 'is 75% ', but"the Total remaining time"is 1H30Mins.

  How Windows calculates the 'Total remaining time? I found what OS will have one or two minutes to display "Total remaining time" after I have the power cable plug-out.

  Which is appreciate to get your answer.

  Horky

  The remaining computing power comes from the numere questioning power management drivers and is a fairly complex calculation based on current usage (the amount of energy is consumed), the capacity of the battery (what total capacity is left and how fully charged is battery) and can also vary depending on what else is plugged into the USB port of the computer , what accessories (memory, video card, etc.) are installed, how good or bad, the battery is to maintain a charge and so on.  There is no particular reason to believe that maybe outside the right-out-of-the-box everything two laptops will show the same calculation even if they are all the same brand and model.

  "Horky.Chen" wrote in the new message: * e-mail address is removed from the privacy... *

  Mr President.

  I checked several laptops that are of the same model, one of them cannot display "Total time remaining" in the power meter. Even other laptops may display, but the values are equivocal. Sometimes the 'remaining power' is 80%, but 'Total remaining time' is 1H20Mins. And sometimes, the "remaining power 'is 75% ', but"the Total remaining time"is 1H30Mins.

  How Windows calculates the 'Total remaining time? I found what OS will have one or two minutes to display "Total remaining time" after I have the power cable plug-out.

  Which is appreciate to get your answer.

  Horky

• Hi all, I bought apple phone I 5s recently is the power button / stop does not. Bought in the United States, but I was shifted to the India, the works of will to guarantee in India please help

  Hi all, I bought apple phone I 5s recently is the power button / stop does not. Bought in the United States, but I was shifted to the India, the works of will to guarantee in India please help

  Ask an authorized service provider regarding iPhones, a guarantee of a country may or may not be honored in another function where you take the device.

  (143868)

• Is there a way to the target url by using the power of Attorney (I want to say is possible to use the proxy to target a site something like that.)?

  Is there a way to the target url by using the power of Attorney (I want to say is possible to use the proxy to target a site something like that.)?

  By default, you can not in Firefox.

  But you can use an add-on like FoxyProxy Standard, I think he understands the functionality you need.

• Malfunction of the power on the Satellite Pro 4270

  I have a problem with my AC adapter (model PA3049U-1ACA): my 4270 Pro Satellite ceased to get power and it worked only with the battery. I have this problem only twice in the last 6 months, but the other times, the problem has been resolved just remove and reinsert the plug in the notebook. Instead this time it does not work.
  How will I know if the problem is due to a broken adapter or a faulty connector "DC in"?
  I searched online for a new AC adapter but I found only "compatible" adapters: they are good or if I should get an original?

  There is another problem: yesterday the internal modem no longer works: would it be a consequence of a failure of the power started yesterday?

  [Edited by: admin on 12 February 06 17:24]

  Hello

  Original AC adapter has this part PA2450U number. If the compatible one has the same characteristics and the same connector, there should not be any problem, but I personally prefer original parts. After you have connected the original adapter, you will be able to check whether the slot is maybe defective.

  As far as I know the modem functionality depends on many things (configuration, hardware malfunction) and control first entry in Device Manager. Please report the status of the modem in Device Manager.

  Good bye

• Unknown buttons under the power button - Tecra A9

  Does anyone know what are the two buttons under the power button?

  thanx

  Hey there.
  The first is called Toshiba Assist button and automatically launch the program.
  The second is the Toshiba presentation button and has the same functionality as the display of connection button in the center of mobility.

  A brief look in the manual is sometimes very useful ;)

• Microsoft comfort keyboard and the keyboard function keys Tecra A3

  I have a Tecra A3 and that you use with a Microsoft Comfort keyboard. The problem is that since the keyboard drivers have been the function keys (Fn + F2 to change the power mode) installed now realize the funcitons additional IE Fn + F2 also opens the folder my pictures. The strangest on East turn on map of wireless network or off with the switch located on the front of the laptop. This has the effect to load a copy of MS Outlook whenever it is switch extra.
  I have the latest version of Microsoft IntelliType Pro (version 5.20.412.0)

  Any idea on how to solve this problem?

  Hello

  Sorry, but you haven't explained do you have this problem now, using laptop or other external keyboard.

  If the problem persists with the help of an external one I think that you can not use combinations of keys FN + FX of Toshiba. Each external keyboard is specific and in my opinion, you should see s operating manuals and check also all additional functions. I'm also sure that you are able to set up some special keys on your own.

  The problem with the WLAN mixer is very strange. Try to delete the specific Microsoft software and check if the feature is as before.

• Qosmio X 500 does not start and the power LED is flashing every 5 seconds

  Hello
  I need help my X 500 does not start now. I tried to launch the NB as usual and suddenly the X 500 start or even power up.

  If I press the power button / stop it makes no noise, the power LED on the button and the second power LED just bliks once and turns on and keep blinking every 5 seconds.

  I tried to:
  * Remove battery and power up with AC only
  * power only to batteries
  * remove the battery power button hold for 30 seconds and over power with AC, battery only athen

  but it did not help.

  I checked the LEDs AC & battery, but they do not blink, they are just RED, so there is no problem in battery or AC.

  No idea where could be the problem?

  Thanks for help
  Frantisek

  Hello

  The failure of RAM could be the reason for this behavior of the laptop.
  Remove the RAM modules with good modules tested and check the functionality of the laptop.
  In the case of RAM isn t the troublemaker, the motherboard could be affected.

  Good luck and share your experience with us.

• Satellite A500 - battery light flashes when connected to the power supply

  Win 7 Satellite A500 PSAM3A-03P00E.

  Battery light flashes when connected to the power supply (intermittent fault), when I disconnect the sector and reconnect the flashing stops and battery (high capacity) continues to receive.

  Also, when battery light blinks the keyboard backlight stays on when it should white and if the backlight is turned off and the battery light starts to blink the keyboard backlight turns on, all other functions seem to work well.

  Charges of battery and the wedges load properly (when the battery flashes).

  Hello

  Have you noticed this problem since the first day of purchase?
  Theoretically, it could be possible that your battery begins to malfunction
  On the other hand, an electrical problem could also be possible

  However, try this:
  Remove the battery and the AC adapter. Then press and hold button power 30 sec long.
  Then insert the battery and plug AC adapter still does that help?

  By the way: this is the BIOS updated? If this isn't the case, perform an update.

• Re: Satellite A30 - battery starts to unload if the power is connected

  Hi all

  My Toshiba laptop Satellite A30-871 began to discharge the battery while the power is connected (the LED shows that AC is connected but laptop consumes the battery power instead of loading battery and the use of current alternative). When the laptop achieved 0% battery turns off. Remove the power plug and reconnect do not resolve the problem, while the computer is turned on, only computer shutdown will begin the battery takes over. Which means that I can use portable so that battery retains some powers. Sometimes, when the laptop is turned off and the battery is charging, battery charging LED starts to blink and I have to remove the power plug and plug back.

  I don "t think it's a bad power connector because the witness indicates the power is connected.

  I wonder if anyone has a solution for me.

  Kind regards
  Nova

  Hello

  Just a question; does the laptop functions and using only the AC adapter (without the battery)?

  If Yes, then I guess that the problem might be related to battery failure.
  Maybe a new battery could solve this problem, but as you know this is just a suggestion

• What does not restart in the FFT functions way?

  Hi all

  I would like to know what that "restart average" made for the FFT functions. According to aid,"reboot on average indicates if the VI restarts the process chosen medium." If restart on average is set to TRUE, the restart of the VI the selected with an average of process. If reboot on average is set to FALSE, the VI does not restart the process chosen sprawl. The default value is FALSE. When you call this VI for the first time, the averaging process restarts automatically. A typical case when you need to reboot on average is when a major change of entry occurs in the middle of the averaging process"

  I realized that the FFT function takes in an array of values and perform the FFT on it. If the FFT function keep a buffer previous values and clears when restart average = true? Because the FFT functions are not Point by point and they take both in all the data to deal with, "a major change of entry occurs in the middle of the averaging process" can be true?

  Thank you!

  Sigh.  I really tried to explain what was going on (probably) with this function, you use (and, I thought naively, you understand), but you got me wrong.

  

  This VI creates a zero average noise signal, providing 1024 points per second.  Do you know what should be the power spectrum of the signal?  Due to the randomness of the input signal, the power (for a small finished sample) spectrum will also have a random component.  If you had several ghosts of power on average, the average would begin to converge with the expected for random noise power spectrum.

  If you run this VI and look at the Spectra resulting (on average), you will notice that the first spectrum is the most "spice" and that spectra are averaged, the variation is reduced and diminishes the value of crete (shown by looking at the scale of Amplitude).  At any time, you can press "Reset average" and see this... reset the average, the following spectrum shows the growing nose, etc.

  It shows the right way to test the function of the power spectrum and discover what he does. My suggestion as to what makes this function seems to be largely correct.

  Bob Schor