|High-performance computing on cloud services
Noise analysis/simulation supercomputing service
UC-win/Road Noise simulation option, analysis support service
|The noise analysis/simulation supercomputing services provide the analysis
result from supercomputer of FOCUS (Foundation for Computational Science).
With this service, the advanced computation performance of supercomputer
can be used to perform the analysis of large-sized data in a short time.
We introduce the summary of this service as below.
|Overview of noise simulation|
|In this service the term "noise" is used, however this service
allows the analysis of "the air vibration which can be perceived by
the human ear".
The methods of expressing the sound behavior digitally can be classified to the following two.
The configuration elements of noise simulation data are "sound source", "obstacle", "sound receiving point".
The omnidirectional point sound source is assumed. The sound power level can be given in multiple frequency configurations.
The sound source cannot be directly moved, however, the effective time can be set per sound source. Therefore, you can place multiple sound sources on the moving path, and setup each effective time based on the speed to provide the same effect as moving. The direction of sound line is assumed to be the global direction, and the number of sound line can be changed based on the predefined rule.
For example, obstacles are the road surface, other vehicles, and the structures/buildings on the road. If the sound line reaches each surface, the reflection or transmission are considered. Depending on the reflection ratio, both the reflection and transmission occur. In this case, it is considered by dividing the sound source into two lines.
In this simulation, the diffraction and interference are not considered.
(3)Sound receiving point
The sound receiving points can be arranged in any position. It is thought to be omnidirectional. As for the sound line to the sound receiving point, the perpendicular drawn from the sound receiving point to the sound source is assumed, and if it is shorter than specific length based on the distance from sound source to receiving point, this sound line is considered as valid.
|The analysis example is shown as below (Figure1). It is assumed that a
sound source is on upper side of the figure of the area, and the 20m of
wall is along the side of sound source from top right to bottom left. The
size of area is 80m x 80m.
Other conditions are as below.
(Reference price:Option basic price US$180/month, two minutes of use: US$4,)
|Advantage of supercomputer|
|The calculation accuracy is largely improved by adding the number of sound
line and sound receiving points in the noise simulation. However, if you
try to improve the calculation accuracy, the following issues occur.
|Parallelization and speed performance|
|The supercomputer consists of the calculators called "node".
FOCUS supercomputer has more than 200 nodes, and 4 nodes of them are used
for this service. As the number of core per node is twelve, the parallel
calculation with total of 48 cores is performed. In addition, the memory
volume per node is 48GB, and 4 nodes are used, therefore, the memory incomparably
larger than the general computer can be used.
In this service, the interface called MPI (Message Passing Interface) is used to perform the parallel calculation with many CPU cores. In MPI, the separate program (process) per CPU core is activated. The separate memory space is assigned per process. This type of parallel process is called as the distributed memory parallel system. In each process, the process is judged and analyzed, and then the total processes are gathered to provide the final result. With this parallel calculation, the advanced calculation performance is available.
The figure4 shows the analysis time of UC-win/Road sample data. As compared to general local machine, it can provide the dozens of times of performance. If you use the latest computer, this difference becomes smaller, the analysis can be performed around 20-30 times of speed.
However, it requires the data file transmission between cloud server system and supercomputer, and the overhead occurs when many CPU cores are activated and synchronized, therefore, the efficiency may be inversely reduced in the small data.
|This service is available with the following procedure. The supercomputing
analysis data files are generated from the UC-win/Road noise simulation
option, and they are registered in the upload window of web application
in Figure 5. This led the automatic analysis with supercomputer.
When the analysis is completed, the mail is transferred to the registered address. You can obtain the analysis result from web application, and check the result by importing into UC-win/Road.
|Price of service|
|Option basic price
*UC-1 for SaaS server license [Until 1user/1GB] : US$40/month is needed separately.
*Upon min 2months application period, it is possible to apply by one month unit. For extension of the period,it shall be applied one month beforehand.
Supercomputing analysis price
Engineer's Studio(R) Supercomputing Option /Noise analysis/simulation supercomputing service
Analysis time by FOCUS supercomputer is measured and the time analyzed by FOCUS supercomputer is totaled at the end of the month and the following fee would be charged as per the total time. (by one minute unit )
* Upon min 2months application period, it is possible to apply by one month unit. For extension of the period, it shall be applied one month beforehand.
The standard UC-win/Road noise simulation option is US$3,000.
|In this service, it is considered that the reduction of analysis time by
reviewing the algorithm of analysis process. In addition, it is also considered
that the addition of the result display function per analysis step and
the analysis based on the specific standard and guideline.
Please expect the additional development and improvement in the future.
|(Up&Coming '11 Late Fall Issue)|