BMe Research Grant
Modern lifestyle – urbanization, motorized transportation and mechanized manufacturing – is accompanied by environmental noise, being a focus areas of environmental protection at the same time due to its significant impact on the human quality of life. Noise protection is a relatively new but dynamically developing sector, which drives continuous improvement by participating manufacturers, experts and regulatory bodies, which in turn has generated a series of research programmes in recent years. Noise control is an essential tool in noise protection. Most efficient implementations of noise control in our days are noise monitoring and noise mapping. However, there are huge potentials in noise control still untouched that could open new perspectives in this area.
The laboratory of acoustics operating at the BUTE Department of Telecommunications provides background for the development of its students and for working on numerous national and European projects. The laboratory contains a well equipped sound studio and a semi-anechoic chamber, as well as wide selection of equipment for acoustical testing and modeling. Its activity covers vibration, vehicle and room acoustics, finite-element modeling and digital studio techniques.
The need for demonstrating noise monitoring data emerged in 2007, during the installation of a noise monitoring system for the construction of Metro Line 4 in Budapest, when both the client and the public wanted noise maps instead of diagrams – and that did not appeared technically feasible at that time. It soon became clear that the underground construction was not the only sector in the construction industry that could utilize real-time noise mapping technology, and this potential encouraged me starting a research in the topic. As the research was not only supported by the industry but also by professionals and the scientific community, I started doctoral studies one year after graduating from the faculty of electrical engineering, with the research topic of “real-time refreshment of noise maps by noise monitoring”.
In 2009, having laid the theoretical basis of noise map refreshment, it turned out that available noise measurement technology – i.e. sampling and processing the cumulative noise level – can only provide the measurement data necessary for the refreshment under special circumstances and entailing serious costs. It was the consequence of other dominant sources operating on the site of noise measurements (in most cases) that made a significant contribution to the cumulative noise level, and could not have been filtered out. This has lead to the extension of the research topic with the problem of “source-selective noise monitoring”.
In 2011, after the theoretic background of source-selective noise monitoring and the first verification laboratory tests had been completed, we had to extend the scope of our research in order to test it in a pilot-project. After a short groping I found the required support within BUTE from the Knowledge Transfer Office (TTI) and the Information Social and Trend Research Centre (ITTK). TTI has provided the resources for the patenting and business planning, while ITTK produced the valorization and the market research for the innovation, both financed by EU funds. As a result, we started the development of a prototype and prepared market launch, which will hopefully ensure the resources for the further research of noise control for a long time.
The aim of research, issues to be addressed
Currently, the primary aim of the research is the development of an effective source-selective noise monitoring system capable of analyzing dominant noise sources in their environment in real-time. The data produced by this system can be utilized for the refreshment of previously calculated noise maps. As the system has very diverse application areas – from the temporary control of music festivals and construction sites to the permanent control of plants, airports and transportation routes and refreshing strategic noise maps of cities – we face significant challenges, and additionally to the scientific aspects we have to consider the market needs as well. Our aim is to facilitate utilization of our results in products in the shortest possible time thus providing noise protection industry with innovative technology and gaining resources for further research.
During the real-time measurement of environmental noise levels in one or more reference points the system performs sensoric observations used by a decision algorithm to identify momentary dominant noise sources and breaks down the cumulative noise level to source-components. Once the noise levels of each sources are determined in the reference points, the system calculates the approximate noise level in each points of a noise map grid using pre-calculated, quasi time-invariant noise propagation factors specific to the site. The calculation is repeated periodically.
Prior to the installation, we survey the site in order to identify any noise sources capable of significantly influencing the noise immission of certain points in the area (dominant sources); having identified these sources we have to determine the location(s) of the monitoring station(s) and once they are installed a data processing center should be established for breaking down the cumulative noise level to source-components via processing sensoric observations by an appropriate algorithm.
During my research, I laid the theoretic basis of real-time noise mapping and source-selective noise monitoring and performed laboratory tests to justify theory. I summarized the two hypotheses (“1. Time Correlation of a Certain Noise Source’s immission Levels in Different Points of Space”, “2. Separation of Multiple Sources’ Cumulative Noise Immission by Measurement”), the theory and the experiments in an article sent to the Noise Control Engineering Journal (NCEJ) for publication (presently under revision).
In parallel with the research, I was working in the noise protection industry and in 2011 I received the license from the Hungarian Engineering Chamber to provide noise and vibration protection expertise. In the course of my work I had the opportunity to participate in numerous national and European noise related projects, like the construction monitoring of Metro Line 4 in Budapest, the subterranean highway in Toulon or the highway bridge in Birmingham, and the environmental authorization of M8 and M9 highways in Hungary, the Warsaw-Radom railway line in Poland and the Bergen Light Rail Train in Norway. I shared my research results regularly at the annual noise protection seminar organized by the national noise society .
As a result of our research, a new innovation has been submitted to the National Authority of Intelligible Rights in 2012 for patenting titled “Method and arrangement for real-time source-selective environmental noise monitoring and mapping”.To help utilization, a market research and a business plan was prepared and we formed a team (acoustic engineer, innovation manager, hardware and software developer) for the development of the prototype.
The research received significant impetus, as two organizations of the Technical University have found it worthy of support, and the market seems to anticipate – according to the market research – a product that embodies the results of the research. Hopefully, the article sent to NCEJ will be published early next year so we can get the critics of the scientific society as well.
The topic is definitely worthy of further research, partly to promote the utilization of source-selective noise monitoring in a wide area – which requires reliable source-identification under various circumstances, and partly to create a learning algorithm capable of building the decision database necessary for the source-selectivity unattended – a stage necessary to further simplify system installation and extend its area of application for a wider range of users.
List of my related publications:
GERÉB GÁBOR, MOLITORISZ PÉTER, RONAN LEROY: On-line-Überwachnung beim Bau der U-Bahn-Linie U4 in Budapest: Gebäudemonitoring, Lärm- und Erschütterungsschutz sowie geotechnische und hydrologische Datenerfassung (in German) – BAUTECHNIK 84:(6) pp. 422-425., 2007
GERÉB GÁBOR: Zajmonitoring szerepe a zajvédelemben (in Hungarian) – Seminar on protection against noise, Sopron, Hungary, 2007.
GERÉB GÁBOR: Közlekedési zaj hatástanulmányok Angliában: hagyomány és korszerűség (in Hungarian) – Seminar on protection against noise, Balatonvilágos, Hungary, 2009
GERÉB GÁBOR: Valós idejű zajtérkép alkalmazása a környezetvédelemben (in Hungarian) – Seminar on protection against noise, Tiszafüred, Hungary, 2010.