Wednesday, June 02, 2010

chrome problem: "could not create directory for unzipping"

when install extension in google chrome, may show a problem named "could not create directory for unzipping"

may work in some systems by running chrome using
chrome.exe --enable-logging --log-level=0 --single-process

Wednesday, April 21, 2010

Matlab black picture problem

Warning: Problems in UIW_SetUpGLPrinting
In C:\Program Files\MATLAB\R2009b\toolbox\matlab\graphics\hardcopy.p>hardcopy at 21
In graphics\private\render at 143
In print at 277
In hgexport at 818
In filemenufcn>localSaveExportHelper at 206
In filemenufcn>localSaveExport at 316
In filemenufcn at 56

Try changing the Renderer property of your figure from OpenGL to ZBuffer.
To do this, use:

set(gcf, 'Renderer', 'ZBuffer')

Friday, December 25, 2009

a three-day snowing



12/24/2009, St. Paul, MN

a cloudy morning - see, gravity waves above Minneapolis




12/17/2009, Minneapolis, MN

a cold day



-20C, 12/15/2009 at Minneapolis, MN

Saturday, December 05, 2009

wind turbine in a stably stratified atmospheric boundary layer



Vortex structures (identified using |omega|-definition) during the beginning ~2min.

Saturday, October 24, 2009

recommend Toyota Yaris



Just bought a 2007 Toyato Yaris Hatchback. It is small, but ridiculously has large room even for my mountain bike. It is so efficient, 40MPG for me including local and highway (half and half).

Friday, October 23, 2009

resolve MPI deadlocking

Deadlock is a problem with blocked communication.

Example 1: always deadlocking

if (rank == 0) then
call MPI_Recv(..., 1, tag, MPI_COMM_WORLD, status, ierr)
call MPI_Send(..., 1, tag, MPI_COMM_WORLD, ierr)
elseif (rank == 1) then
call MPI_Recv(..., 0, tag, MPI_COMM_WORLD, status, ierr)
call MPI_Send(..., 0, tag, MPI_COMM_WORLD, ierr)
endif


Example 2: sometimes deadlocking: MPI is using internal buffers (the “message envelope”) to cache messages. A blocked comm pattern may work for some values of count, and then fail as count is increased.

if (rank == 0) then
call MPI_Send(..., 1, tag, MPI_COMM_WORLD, ierr)
call MPI_Recv(..., 1, tag, MPI_COMM_WORLD, status, ierr)
elseif (rank == 1) then
call MPI_Send(..., 0, tag, MPI_COMM_WORLD, ierr)
call MPI_Recv(..., 0, tag, MPI_COMM_WORLD, status, ierr)
endif


A couple of ways to fix this problem.
Method 1: reverse the order of one of the send/receive pairs

if (rank == 0) then
call MPI_Send(..., 1, tag, MPI_COMM_WORLD, ierr)
call MPI_Recv(..., 1, tag, MPI_COMM_WORLD, status, ierr)
elseif (rank == 1) then
call MPI_Recv(..., 0, tag, MPI_COMM_WORLD, status, ierr)
call MPI_Send(..., 0, tag, MPI_COMM_WORLD, ierr)
endif


Method 2: using unblocked communication

if (rank == 0) then
call MPI_Isend(..., 1, tag, MPI_COMM_WORLD, req, ierr)
call MPI_Recv(..., 1, tag, MPI_COMM_WORLD, status, ierr)
call MPI_Wait(req, status)
elseif (rank == 1) then
call MPI_Recv(..., 0, tag, MPI_COMM_WORLD, status, ierr)
call MPI_Send(..., 0, tag, MPI_COMM_WORLD, ierr)
endif

Sunday, October 18, 2009

Remodeling at SAFL




Recently, SAFL is remodeling the entrance.
Taken at 10/13/2009 11:16 by Fujifilm FinePix805; Shutter 1/204seconds; F2.83; ISO100; no flash.

front and backyard of my current house




time: 10/18/2009, 17:09
camera: Fujifilm FinePix805
shutter: 1/405 seconds
aperture: F2.83
iso200; no flash