Category Archives: Tricks

Education, Tricks

Thank You Synthtopia. Audio is aurally levitating.

Saw this article on Synthtopia.  People who love audio already knew of its power.  Behold!

Three-Dimensional Mid-Air Acoustic Manipulation (2013,2014-)

Yoichi Ochiai (The University of Tokyo)
Takayuki Hoshi (Nagoya Institute of Technology)
Jun Rekimoto (The University of Tokyo / Sony CSL)

A pop song for science.

UPDATE: Apparently, this is quite a growing interest

The most fascinating tid bit thus far has been the history, via patents, of this type of research. As stated by the lovely compiler from reddit, heyheythroemaway, “patents are like karmadecay for science gifs.”  Does anyone have an easy way to look up these patents?  A WordPress plugin?

  • Barmatz, Martin B., System for controlled acoustic rotation of objects U. S. Patent 4393706, July 1983.
  • Lee, Mark C., Acoustic suspension system U.S. Patent 4402221, September 1983.
  • Barmatz, Martin B., Granett, Dan, Lee, Mark C., “Vibrating-chamber levitation systems” U. S. Patent 4549435, October 1985.
  • Barmatz, Martin B., Allen, James L., Granett, Dan, Gravity enhanced acoustic levitation method and apparatus. U.S. Patent 4520656, une 1985.
  • Barmatz, Martin B., Allen, James L., “Single mode levitation and translation.” U.S. Patent 4736815, April 1988.
  • Peterson, Stephen C., Brimhall, Owen D., McLaughlin, Thomas J., Baker, Charles D., Sparks, Sam L., “Methods and apparatus for moving and separating materials exhibiting different physical properties”. U.S. Patent 4759775, July 1988.
  • Barmatz, Martin B., Garrett, Steven L., Stabilization and oscillation of an acoustically levitated object. U. S. Patent 4773266, September 1988.
  • Danley, Thomas J., Rey, Charles A., “Horn loaded transducer for acoustic levitation” U.S. Patent 4841495, June 20, 1989.
  • Ohkawa, Tihiro , “Acoustically fluidized bed of fine particles”. U.S. Patent 4948497, August 1990.
  • Barmatz, Martin B., Aveni, Glenn, Putterman, Seth, Rudnick, Joseph, “Acoustic positioning and orientation prediction”. U.S. Patent 4964303, October 1990.
  • Danley, Thomas J., Merkley, Dennis R., Rey, Charles A., Naperville, IL. “Method and apparatus for acoustic levitation”. U.S. Patent 5036944, August 1991.
  • Rey, Charles A., Merkley, Dennis R. “Aero-acoustic levitation device and method” U.S. Patent 5096017, March 1992.
  • Ohkawa, Tihiro, “Plasma processing apparatus for controlling plasma constituents using neutral and plasma sound waves”. U.S. Patent 5350454, September 1994.
  • Leung, Emily W., Man, Kin F., “Plasma heating for containerless and microgravity materials processing”. U.S. Patent 5374801, December 1994.
  • Nuscheler, Reinhard, Wessner, Hans, “Closed loop control apparatus with frequency filters for controlling an air gap width in electromagnetic levitation systems”. U.S. Patent 5387851, February 1995.
  • Goforth, Robert R., Ohkawa, Tihiro. “Acoustic barrier separator”. U.S. Patent 5419877, May 1995.
  • Guign , Jacques Y., Barmatz, Martin B., Jackson, Henry W., Koptenko, Sergei V., “Acoustic beam levitation”. U.S. Patent 5500493, March 1996.
Applications, Tricks

Recovering Pictures from a Cell Phone

I recently had a crash on my phone where I thought I lost the majority of my pictures. Luckily, I was able to do a recover using PhotoRec. The only problem is that for some reason, there was a glitch with the file system on my phone and each time it neared the end, the program would go backwards several thousand sectors and start recovering the same files all over again.

The next problem was that I had several duplicate files and needed to prune redundancies. Thankfully there was a program, FSlint, that was designed to do just that. Using a file size, MD5sum, and SHA1sum analysis regiment to find the duplicate files, I was able to eradicate all of the extra, unnecessary, redundant versions of each picture.

Now my problem was that I had several recoup.dir directories. I wanted to take all of the JPEGs from their respective folders and move them to a single, good folder. Searching around the Internet led to this post on LinuxQuestions.org. Their suggested command worked beautifully:

find (start directory) -iname “all my files type” -exec cp {} (target_dir) \;

Now I had all of my pictures recovered, duplicates removed, sitting in a single directory, however, their original file names and dates were incorrect. Thankfully I found this little handy script on TuxRadar that allowed me to rename the files and update their timestamp according to their embedded EXIF data:

find -name ‘*.jpg’ | while read PIC; do
DATE=$(exiftool -p ‘$DateTimeOriginal’ $PIC |
sed ‘s/[: ]//g’)
touch -t $(echo $DATE | sed ‘s/\(..$\)/\.\1/’) $PIC
mv -i $PIC $(dirname $PIC)/$DATE.jpg
done

Thanks to the wonderful world of FLOSS, I was able to complete my mission of recovering my, once lost, pictures, rename them according to their meta data, and live a happy Saturday. I love the community.

Tricks

Make KDE Plasma Run Faster

So I have been trying to find various ways to speed up the performance of my new GNU/Linux system. I decided to search for KDE speed improvements and came across this YouTube video:

I tried the trick, killing Plasma and rerunning it using the Qt 4.5 rending method. I received a substantial performance increase in my graphics rendering. To do the same on your system, run the following commands first to see if this trick does speed up your performance:

kquitapp plasma-desktop
plasma-desktop -graphicssystem raster

Then, do some widget resizing, use the launcher menu, etc. The easiest one to see the performance increase, like in the video, is to rotate the folder widget. Mine was jerky without this change and very smooth after the fact.

If this did speed up your system, make the following changes to your /usr/share/autostart/plasma-desktop.desktop file so that it runs the raster graphicssystem by default next time you restart Xorg/KDE:

sudo nano /usr/share/autostart/plasma-desktop.desktop

Add the -graphicssystem raster to the current Exec line so that it looks something like this:

Exec=plasma-desktop -graphicssystem raster

That’s it. Now I did read some downsides (possibly more memory usage) in the More 2D in KDE article linked below, however, for my uses, it seems to help more than it hurts. Your mileage may vary.

References:

Dramatically speed up KDE Plasma
Is KDE4 Slow? (forum.kde.org)
More 2D in KDE