Application of Grid Infrastructure to Noise Map Calculation of Large City Areas MACIEJ SZCZODRAK, JÓZEF KOTUS, ANDRZEJ CZYŻEWSKI, BOŻENA KOSTEK Gdansk University of Technology, Multimedia Systems Department ul. Narutowicza 11/12, 80-233 Gdansk, Poland {andcz, joseph, szczodry, bozenka}@sound.eti.pg.gda.pl
Outline Introduction Methodology Road noise source model Propagation model Algorithm Results Future work
Introduction - motivation Raising awareness about problem of environmental noise occurrence and its influence on hearing Reducing hearing impairments caused by excessive environmental noise European Directive 2002/49/EC, published on 18/02/2002 (assessment and management of environmental noise)
Introduction - motivation Noise annoyance Noise Induced Hearing Loss
Grid computing infrastructure PLGRID+ ACOUSTIC
Noise mapping in grid computing METHODOLOGY
Methodology Noise source part Propagation part
Noise mapping in grid computing ROAD NOISE SOURCE MODEL
Road noise source model Road as line source consists of 2 submodels: The vehicle model, describing the sound power of single moving vehicle The traffic model, combining the noise emission of numerous single vehicles into the sound power per meter length of the line source Two main sources of vehicle s noise taken into account in mathematical model: interaction between wheel and road surface vehicle s propulsion (engine, transmission, exhaust)
Road noise source model Category Name Description 1 2 Light motor vehicles Medium heavy vehicles Passenger cars, delivery vans <3.5t, SUV's, MPV's including trailers and caravans Medium heavy vehicles, delivery vans >3.5t, buses, touring cars, etc. with two axles and twin tire mounting on rear axle Vehicle category according to the EU/ECE type approval M1 and N1 M2, M3 and N2, N3 3 Heavy vehicles Heavy duty vehicles, touring cars, buses with three or more axles M2 and N2 with trailer, M3 and N3 4 Powered two-wheelers 4a motorcycles, tricycles or quads, engine <50 ccm 4b motorcycles, tricycles or quads, engine >50 ccm L3, L4, L5, L7
Road noise source model 13
Noise mapping in grid computing PROPAGATION MODEL
Methodology on the basis of Harmonoise/Imagine projects Industrial sources Airport sources 15 Propagation classes Railroad sources PROPAGATION L den L night Road Traffic sources P2P model Road properties Traffic data Meteorological conditions Geometry (surroundings buildings)
Propagation model Based on Point to Point Harmonosie model The acoustic ray tracing method Additional libraries: Harmonoise, CGAL, Tardem Geometrical description of sources and buildings Meteorological conditions
The acoustic ray tracing method
Noise mapping in grid computing ALGORITHM
Parallel processing START PREPARE DATA (MASTER) PARALLEL PROCESSING Read input data Spread data to all cores All cores received task? YES Worker returned output? YES All tasks calculated? YES Format and save output data STOP NO NO NO Send next task to worker core Wait for workers output Send next task to worker core The usage of MPI* Master core distributes tasks to the others In the beginning master sends 1 task to each core When worker core finishes computations, sends message with outcome Master receives outcome and sends next task to worker End, when all tasks are processed *MPI (Message Passing Interface) - is a specification for an API that allows many computers to communicate with one another. It is used in computer clusters and supercomputers.
Service usage scenario Scenario for the prototype stage of service User prepares the input data locally using dedicated software (i.e. CadnaA) Service is being run on PLGrid clusters User gets the output data and analyses it locally Input data editor Input data source ssh sftp Acces node (QCG-UI) PLGrid Clusters Outcome analysis visualization The working scheme of the prototype of the noise service
Access to the service Access to the service by QosCosGrid client Service installed in TASK (Gdansk) and Cyfronet (Cracow) Multi-cluster working of the service Code compiled with an extended version of OpenMPI QCG-OMPI Installed in Cyfronet, work in progress in WCSS (Wroclaw)
Noise mapping in grid computing RESULTS
Computed noise map of large urban area (Gdansk - road noise)
Evaluation of the results Noise Prediction Model (Grid calculation) Noise map calculated using CadnaA software Difference map calculation > -6.0 db > -4.5 db > -3.0 db > -1.5 db > 1.5 db > 3.0 db > 4.5 db > 6.0 db NPM (Grid) CadnaA software Difference map
Evaluation of the results Histogram of difference of noise levels in large area (338,099 number of points) 25 20 N [%] 15 10 5 0-12 -6-5 -4-3 -2-1 0 1 2 3 4 5 6 12 >12 ΔL [db]
Calculation time results Scenario grid raster [m] points cores time [s] 1 16 16 256 32 1908 2 8 8 1024 32 7452 3 4 4 3969 64 16974 4 2 2 15625 64 70895 Time [s] 0 1 2 3 4 5 6 7 8 1 Scenario 2 3 4
Future work DYNAMIC NOISE MAP
Autonomous noise monitoring stations Central monitoring unit (data processing, remote control)
Dynamic noise map
Multimedia Noise Monitoring System Noise Impact on Hearing Monitoring station Database Noise Map Terrain model Sound propagation modeling
Dynamic noise map 15:00 00:00
NEAR FUTURE Noise impact on hearing in grid computing
Introduction Today s methods of hearing impairment risk evaluation are mostly based on the equal energy hypothesis Time characteristics of noise are ignored while the main emphasis is put on the equivalent noise level Proposal of an assessment of noise-induced harmful effects on human hearing system It is based on some psychoacoustical properties of the human hearing system and, at the same time, it takes into account time and frequency characteristics of noise
Simulation of noise exposure during outdoors concert Noise map for the outdoor loud acoustic event (open field musical concert) left, and the map of maximum TTS values - right
Simulation of noise exposure during outdoors concert 90-100 80-90 70-80 60-70 50-60 f [Hz] 99 92 85 78 L [dba] 100 70 60 90 80 150 8 15 22 29 36 43 50 57 64 71 Distance [m] 30-36 24-30 18-24 12-18 6-12 0-6 f [Hz] 99 92 85 78 TTS [db] 6 18 12 30 24 36 10 8 15 22 29 36 43 50 57 64 Distance [m] 71 Spectrum distribution of acoustic energy of noise source (left) and TTS effect evoked by the exposure to that noise (right)
Acknowledgements The project is partially subsidized by the PLGrid Plus "Acoustics" project