New Products
High-performance computing on cloud services
Noise analysis/simulation supercomputing service

UC-win/Road Noise simulation option, analysis support service

Price: US$180/Month Release: August 9, 2011

Introduction
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.
  • Discretization of the equation of wave phenomenon such as boundary element method
  • Assumption of finite number of sound line using the sound linearity
Our simulation service uses the latter "Sound line".
The configuration elements of noise simulation data are "sound source", "obstacle", "sound receiving point".

(1)Sound source
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.

(2)Obstacle
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.
Analysis example
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.
  • Sound source level:112dB
  • Sound source frequency:1000Hz
  • Elapsed time in analysis:0.26 seconds
  • Analysis time increments:0.01 seconds
In case of this data, the calculation time is two minutes using 1 node.
(Reference price:Option basic price US$180/month, two minutes of use: US$4,)

Figure1 Analysis example

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.
  • The calculation time increases based on the calculation accuracy. It takes from several hours to dozens of hours, or several days.
  • As the required memories increase, the calculation cannot be performed due to the lack of memory.
    This type of problem can be solved by the supercomputer. The advantage of using the supercomputer is as follow.
  • The advanced calculation performance can largely reduce the analysis time.
  • With the large volume memory, the large-sized data can be analyzed.
  • As the CPU of local machine is not occupied, the productivity of other works is improved.
  • As the hardware and operating environment is not necessary, the advanced calculation performance can be used with the low specific machine.

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.


 
Figure2 Node configuration and main memory volume Figure3 Parallel calculation with MPI 


Figure4 Analysis time of sample data 

Using method
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.

Figure5 Upload image of analysis data

Price of service
Option basic price
Service name Price
Noise simulation supercomputing on cloud option US$180/Month

*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 )
Total analysis time Price
-up to 1 hour US&2/minute
-up to 5 hours US$1.8/minute
Over 5 hours US$1.5/minute

* 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.

Future development
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)
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