I am doing my project. and it's about a DC-DC converter. I am using HCPL 3021 as a driver for the MOSFET IPPR045C7. in open loop cicuit, I am using Vin=60V, with duty cycly = 60% of PWM signal (F=20KHz). The output voltage should be Vout=36V. But it's not. I got Vout=16V. even with a load connected the voltage remains wrong. the circuit is shown in the joined picture. Can you please help me and tell me what's wrong with circuit? Is the ground connection wrong?
my circuit is shown on the picture. the problem is the output of the mosfet does't work as desired. For example, If I use Vin=100V and the duty cycle is 50%, the output is Vout=19V.  Anyway, the output is not even near to the desired value. can you help, please?
I have a Python program that uses the "threading" module. Once every second, my program starts a new thread that fetches some data from the web, and stores this data to my hard drive. I would like to use sqlite3 to store these results, but I can't get it to work. The issue seems to be about the following line:  conn = sqlite3.connect("mydatabase.db")    If I put this line of code inside each thread, I get an OperationalError telling me that the database file is locked. I guess this means that another thread has mydatabase.db open through a sqlite3 connection and has locked it. If I put this line of code in the main program and pass the connection object (conn) to each thread, I get a ProgrammingError, saying that SQLite objects created in a thread can only be used in that same thread.   Previously I was storing all my results in CSV files, and did not have any of these file-locking issues. Hopefully this will be possible with sqlite. Any ideas? Suppress "In:" biblatex Which Harry Potter works are considered canon? How can I prevent data theft from a company?  Are there any solutions to this problem?  Is there any software that encrypts important data (.doc, .xls, etc.) and prevents it from copying?  I need a solution where employees can read/write documents but can not copy then to a USB drive or e-mail them. If $[G' : G'']\leq p^2$, then $G'$ is abelian. Problem : Let $G$ be a p-group and $G'$ denote the commutator subgroup of $G$. If $[G' : G'']\leq p^2$, then $G'$ is abelian.  It is easy to prove it for the case of $[G' : G'']=1$ since G is solvable. But it is too hard to prove the other cases. Please give me any advice or solutions. Thanks in advance. mysql select from n last rows I have a table with index (autoincrement) and integer value. The table is millions of rows long.  How can I search if a certain number appear in the last n rows of the table most efficiently? 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I'm using ArcGIS 10.3 (Desktop), and I'm trying to measure the distance between points following a path determined by a set of polylines.  Hand measurement is not a viable option-- there are ~7500 points, and my polyline set is the global coastline.  The ultimate goal is to get the spacing of these points along the polylines, so that I can analyze this with respect to a few other variables.   I can read python-- with a bit of effort-- but not write or edit it, so code-based solutions will not be particularly useful to me.  I have tried using the linear referencing tools-- I snapped the points to the lines, then transformed the polylines to routes and used 'locate features'-- but because my points are not (entirely) ordered along the path, using the difference between  linear reference locations of subsequent points yields some fairly unlikely answers.  In addition, spot checks of (hand-measured, using the built-in path length measuring tool) point-to-point along-polyline distance yield different answers than given by the corresponding linear references for the point pair. (Some of the answers were close enough that they could very well be measurement error on my part, but others were nearly 20%, despite my having zoomed in and snapped the measurement cursor to the polyline, proceeding vertex-to-vertex.)  Sorting first by linear distance seems to fix the first problem, but in light of the second one, I remain skeptical of this process.   I then tried simply splitting the polylines into segments ('split line at point') using the (snapped) points as the dividers, with the eventual goal of finding the segment length with the calculate geometry feature.  This produced gibberish. I'm not sure what criteria ArcGIS used to split the lines, but it wasn't the point set I provided.  Segments in the resulting shapefile ran right through tens of points, only to terminate at a place with no point. (Also, there were segments utterly empty of points...you get the gist.) I reiterate that the pointset was specifically snapped to the polylines, so this problem shouldn't be caused by excessive distance between the point and the polyline.  I'm at a bit of a loss, here: could someone point out where I might have gone astray and/or suggest a solution?  Or, failing that, a new method that I could try?  It seems like a fairly basic (not necessarily simple, but fundamental) analysis to do with geographic data, and I don't understand why it has presented so many difficulties. 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I am beginner in graph theory so i will be very thankful if i get some simple approach to solve the problem(Not by using some difficult theorems).