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Evaluation of PM2.5 Components and Source Apportionment at a Rural Site in the Ohio River Valley RegionDeshpande, Seemantini R. 27 September 2007 (has links)
No description available.
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Temporal Variation In Aerosol Composition At Northwestern TurkeyGenc Tokgoz, D. Deniz 01 February 2013 (has links) (PDF)
Daily aerosol samples (PM) were collected at a rural station, which is 5 km away from the Turkish-Bulgarian border between April 2006 and March 2008. Aerosol samples were analyzed for elements by ICPMS, ions by IC and black carbon by aethalometer to provide a multi-species aerosol data set, which can represent aerosol population for Northwestern Turkey and Eastern Europe. Average concentration of SO42-, NO3- and NH4+ was 5.8, 2.9 and 2.0 &mu / g m-3, respectively, while total aerosol mass was 66 &mu / g m-3. Seasonal variation of crustal species had maxima in summer, while most of the anthropogenic species had maxima in winter. Rainfall was found as the only local meteorological parameter affecting aerosols concentrations. The dominant sectors of air masses arriving the Northwestern Turkey were northeast in summer and west-northwest in winter. Air masses were classified into five clusters regarding their wind speed and direction. Most species indicated significant differences between clusters. The influence of forest fires in Ukraine and Russian Federation was identified by cluster analysis using soluble K as tracer. Source apportionment of PM was carried out by EPA PMF model and five sources were resolved. Crustal emissions were found to be the major contributor to PM (41%). The second largest source was distant anthropogenic sources with a contribution of 26%. Traffic was also a remarkable source with 16% contribution. Sea salt and stationary combustion sources accounted for 9% and 8% of PM, respectively. Potential source regions of resolved sources were determined by potential source contribution function (PSCF).
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Investigation Of The Relationship Between Aerosol And Rainwater CompositionTurkum, Ahmet 01 September 2004 (has links) (PDF)
Chemical composition of particles and rain water at three sites in Turkey were extensively compared to determine if there is a relationship between aerosol and rain composition. If such relationship exists, it can allow one to construct rain water composition using aerosol data. This is important because, rain composition data is scarce as sampling and analysis of very low concentrations of elements and ions in rain water is more difficult compared to sampling and analysis of atmospheric aerosol.
Results showed that aerosol composition can be closely reflected in composition of rain water if below cloud processes dominate over the incloud processes. This is clearly observed for crustal elements in all stations and for most of the elements in urban Ankara station. However, in rural stations there were differences in rain and aerosol that is attributed to significant contribution from in cloud processes.
Seasonal patterns and enrichment factors observed in aerosol composition showed general agreement with corresponding temporal variations observed in rain water concentrations of elements, but short term variations became visible only if data is averaged over a long period of time. These observations suggest that certain features of rain water composition can be constructed from if concentration data is available for aerosols. However it should be noted that there are also significant differences between stations and between elements or element groups, indicating that composition of rain water constructed from aerosol data can only be a crude one. Similarities between rain and aerosol compositions is more pronounced in urban Ankara station compared to rural stations used in this study.
Factor analysis performed to aerosol and rain water data sets showed that source types affecting chemical composition of rain and particles are generally the same, bur contribution of each source type to rain and aerosol composition shows differences.
Similarly, the source regions, defined by potential source contribution function, affecting aerosol and rain compositions are not identical. In Antalya station Source regions affecting chemical composition of rain water are more local compared to source regions affecting composition of aerosol. Same difference is not observed in Amasra station.
Scavenging ratios is found to be a suitable tool to construct rain water composition using aerosol data. Scavenging ratios calculated using paired daily data are more variable both between stations and within a station. Long-term averaged data was found to be more reliable for calculating SRs of elements and ions at all stations.
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Development Of Gis Based Trajectory Statistical Analysis Method To Identify Potential Sources Of Regional Air PollutionYikmaz, Riza Fikret 01 May 2010 (has links) (PDF)
DEVELOPMENT OF GIS BASED TRAJECTORY STATISTICAL ANALYSIS METHOD TO IDENTIFY POTENTIAL SOURCES OF REGIONAL AIR POLLUTION
Yikmaz, Riza Fikret
M.Sc., Department of Geodetic and Geographic Information Technologies
Supervisor: Prof. Dr. Gü / rdal Tuncel
Co-supervisor: Assoc. Prof. Dr. Zuhal Akyü / rek
May 2010, 186 pages
Apportionment of source regions affecting a certain receptor in the regional scale is necessary information for air quality management and development of national policy for exchange of air pollutants with other countries. Source region apportionment can be studied either through numerical modeling or by using trajectory statistics that is a hybrid methodology of modeling and measurements. Each of these approaches has their advantages and disadvantages.
In this study treatment of back-trajectory segments in Potential Source Contribution Function (PSCF), which is one of the tools used in trajectory statistics will be investigated, to increase the reliability of the apportionment process. In the current method run in GIS, especially two parameters gains importance. One is that the vertical locations of trajectory segments are not taken into account at present. In this study, how the evaluation of the segments in 3-D instead of 2-D could improve the results will be assessed. The other parameter that is rainfall at each segment will be included in the PSCF calculations and its effects on the spatial distribution of PSCF values will be evaluated. A user interface in Geographical Information System (GIS) will be developed for effective use of improved methodology.
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Composition Of Atmosphere At The Central AnatoliaYoruk, Ebru 01 January 2004 (has links) (PDF)
Concentrations of elements and ions measured in samples collected between February 1993 and December 2000 at a rural site in central Anatolia were investigated to evaluate the chemical composition of atmosphere at central Anatolia, to determine pollution level of the region, to study temporal variability of the pollutants and to investigate the sources and source regions of air pollutants in the region.
Level of pollution at central Anatolia was found to be lower than the pollution level at other European countries and Mediterranean and Black Sea regions of Turkey.
Enrichment factor calculations revealed that SO42-, Pb and Ca are highly enriched in the aerosol / whereas, soil component has dominating contribution on observed concentrations of V, Mg, Ca and K.
SO42-/(SO2+SO42-) ratio observed in Ç / ubuk station indicates that contribution of distant sources is more important than the contribution of local sources on observed SO42- levels. SO42-/NO3- ratio calculations showed that Central Anatolia is receipt of SO42- from Eastern European countries.
Positive Matrix Factorization (PMF) analysis revealed 6 source groups, namely motor vehicle source, mixed urban factor, long range transport factor, soil factor, NO3- factor and Cd factor.
Distribution of Potential Source Contribution Function (PSCF) values showed that main source areas of SO42-, NH4+ and Cd are western parts of Turkey, Balkan countries, central and western Europe, central Russian Federation and north of Sweden and Finland / NO3- are the regions located around the Mediterranean Sea / and there is no very strong potential source area observed for NH3 and Pb.
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Investigation Of 8-year-long Composition Record In The Eastern Mediterranean PrecipitationIsikdemir, Ozlem 01 January 2006 (has links) (PDF)
Measurement of chemical composition of precipitation is important both to understand acidification of terrestrial and aquatic ecosystems and neutralization process in the atmosphere. Such data are scarce in the Mediterranean region. In this study, chemical composition of daily, wet-only, 387 number of rain water samples collected between 1991 and 1999 were investigated to determine levels, temporal variation and long-term trends in concentrations of major ions and trace elements between 1991 and 1999. Samples had already been collected and some of the analysis had been completed. The anions SO42-, NO3- and Cl- were analyzed by HPLC coupled with UV-VIS detector, NH4+ was analyzed by colorimetry and H+ ion was analyzed by pH meter. The major ions and trace metals were analyzed by using Atomic Absorption Spectrometry (AAS) and Graphite Furnace Atomic Absorption Spectrometry (GFAAS). In this study complete data set were generated by analyzing samples that had not been previously analyzed for major ions and trace elements with Inductively Coupled Plasma with Optical Emission Spectrometry (ICP-OES).
Statistical tools were used to determine the distribution of the pollutants. The rain water data tends to be log-normally distributed since data show large variations due to meteorological conditions, physical and chemical transformations and air mass transport patterns. The median pH of the rain water was found to be 5.29, which indicates that the rain water is not strongly acidic. This case is not a result of lacking of acidic compounds but rather indicates extended neutralization process in rain water. Eastern Mediterranean atmosphere is under the influence of three general source types: (1) anthropogenic sources, which are located to the north and northwest of the basin brings low pH values to the region (SO42-, NO3- ions) / (2) a strong crustal source, which is dried and suspended local soil and air masses transported from North Africa transport which have high pH values (Ca2+, Al, Fe ions) and (3) a marine source, which is the Mediterranean Sea itself (Na+, Cl- ions). In the region, the main acid forming compounds are H2SO4 and HNO3 whereas / CaCO3 and NH3 are responsible for the neutralization process.
To describe the level of pollutant concentrations and the factors that affect their variations in rain water / ion compositions, neutralization of acidity, short and long-term variability of ions and elements, their time trend analysis and wet deposition fluxes were investigated briefly. Positive matrix factorization (PMF) was used to determine components of ionic mass in the precipitation. In Antalya Station the rain water has five factors: free acidity factor, crustal factor, marine factor, NO3- factor and SO42- factor. Potential Source Contribution Function (PSCF) and trajectory statistics were used to determine source regions generating these components. NO3- has potential source regions of Western Mediterranean countries and North Africa, whereas SO42- has additional southeasterly trajectory components of Israel and south east of Turkey.
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Investigation Of Short And Long Term Trends In The Eastern Mediterranean Aerosol CompositionOzturk, Fatma 01 January 2009 (has links) (PDF)
Approximately 2000 daily aerosol samples were collected at Antalya (30° / 34& / #900 / 30.54 E, 36° / 47& / #8217 / 30.54N) on the Mediterranean coast of Turkey between 1993 and 2001. High volume PM10 sampler was used for the collection of samples on Whatman& / #8211 / 41 filters. Collected samples were analyzed by a combination of analytical techniques. Energy Dispersive X-Ray Fluorescence (EDXRF) and Inductively Coupled Plasma Mass Spectrometry (ICPMS) was used to measure trace element content of the collected samples from Li to U. Major ions, namely, SO42- and NO3-, were determined by employing Ion Chromatography (IC). Samples were analyzed in terms of their NH4+ contents by means of Colorimetry. Evaluation of short term trends of measured parameters have been shown that elements with marine and crustal origin are more episodic as compared to anthropogenic ones. Most of the parameters showed well defined seasonal cycles, for example, concentrations of crustal elements increased in summer season while winter concentrations of marine elements were considerably higher than associated values for summer. Seasonal Kendall statistic depicted that there was a decreasing trend for crustal elements such as Be, Co, Al, Na, Mg, K, Dy, Ho, Tm, Cs and Eu. Lead, As, Se and Ge were the anhtropogenic elements that decreasing trend was detected in the course of study period. Cluster and Residence time analysis were performed to find the origin of air masses arrving to Eastern Mediterranena Basin. It has been found that air masses reaching to our station resided more on Balkans and Eastern Europe. Positive Matrix Factorization (PMF) resolved eight factors influencing the chemical composition of Eastern Mediterranean aerosols as local dust, Saharan dust, oil combustion, coal combustion, crustal-anthropogenic mixed, sea salt, motor vehicle emission, and local Sb factor.
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Comparison Of The Rural Atmosphere Aerosol Compositions At Different Parts Of TurkeyDogan, Guray 01 January 2005 (has links) (PDF)
Long term data generated at four rural stations are compared to determine similarities and differences in aerosol compositions and factors contributing to observed differences at different regions in Turkey. The stations used in this study are located at Mediterranean coast (20 km to the west of Antalya city), Black Sea coast (20 km to the east of Amasra town), Central Anatolia (Ç / ubuk, Ankara) and Northeastern part of the Anatolian Plateau (at Mt. Uludag). Data used in comparisons were generated in previous studies. However, some re-analysis of data were also performed / (1) to improve the similarities of the parameters compared and (2) to be able to apply recently-developed methodologies to data sets.
Data from Mediterranean and Black Sea stations were identical in terms of parameters measured and were suitable for extensive comparison. However, fewer parameters were measured at Ç / ubuk and Uludag stations, which limited the comparisons involving these two stations. Comparison included levels of major ions and elements, short-term and seasonal variations in concentrations, background (baseline) concentrations of elements, flow climatology of regions, correlations between elements, potential source areas affecting regions, and source types affecting chemical composition of particles.
Comparison of levels of measured parameters in four regions showed that there are some differences in concentrations that arise from differences in the local characteristics of the sampling points. For example very high concentrations of elements such as Na and Cl in the Mediterranean region is attributed to closer proximity of the Antalya station to coast and not a general feature of the Mediterranean aerosol. There are also significant regional differences in the concentrations of measured elements and ions as well. Concentrations of anthropogenic elements are very similar at two coastal stations (Antalya and Amasra), but they are approximately a factor of two smaller at the two stations that are located on the Anatolian Plateau. This difference between coastal and high altitude plateau stations, which is common to all anthropogenic species, is attributed to different source regions and transport mechanisms influencing coastal regions and Anatolian Plateau.
Some statistically significant differences were also observed in the temporal variations of elements and ions measured in different stations. The elements with crustal origin showed similar seasonal pattern at all stations, with higher concentrations in summer and lower concentrations in winter. This difference between summer and winter is attributed to suppression of re-suspension of crustal aerosol from wet or ice-covered surface soil in winter. Concentrations of anthropogenic elements, on the other hand, did not show a statistically significant seasonal trend at Amasra, Ç / ubuk and Uludag stations, but they have higher concentrations during summer months at the Antalya station. This difference between Mediterranean aerosol and aerosol at the Central and Northern Turkey is due to influence of more local sources on Ç / ubuk, Amasra and Uludag stations and domination of more distant source in determining aerosol composition at the Mediterranean region. A similar conclusion of strong influence of local sources on chemical composition of particles at the Central Anatolia was also suggested by the comparison of baseline concentrations in each station.
General features in flow climatology (residence times of upper atmospheric air masses) in each region are found to be similar with more frequent flow from W, WNW, NW and NNW wind sectors. Since these are the sectors that include high emitting countries in Eastern and Western Europe and Russia, transport from these sectors are expected to bring pollution from both distant European countries and more local Balkan countries and western parts of Turkey.
Flow climatology in stations showed small, but statistically significant, differences between summer and winter seasons. These variations suggested that the station at the Central Anatolia and Black Sea (Ç / ubuk Amasra and Uludag stations) are affected from sources located at the Western Europe in winter season and from sources located at the Eastern Europe in summer. Mediterranean aerosol, on the other hand, are affected from sources at the Western Europe and do not show any seasonal differences. This variation in flow climatology between summer and winter seasons (and lack of variation at the Mediterranean station) is supported by the seasonal variation (and lack of variation at the Mediterranean station) in SO42-/NO3- ratio measured at the stations.
Potential source contribution function (PSCF) values are calculated for selected elements and ions in each station. Statistical significance of calculated PSCF values is tested using bootstrapping technique. Results showed that specific grids at Russia and at Balkan countries are common source regions affecting concentrations of anthropogenic elements at all four regions in Turkey. However, each station is also affected from specific source regions as well. Aerosol composition at the Anatolian Plateau are affected from sources closer to the sampling points whereas Mediterranean and Black Sea aerosol are affected from source regions that farther away from the receptors. It should be noted that the same conclusion is also reached in comparison of seasonal patterns and baseline concentrations at these stations.
Types of sources affecting aerosol composition at Black Sea, Mediterranean and Central Anatolia are also compared. Source types affecting atmospheric composition in these regions were calculated using positive matrix factorization (PMF). The results showed that aerosol at the Black Sea, Central Anatolia and Mediterranean atmosphere consists of 8, 6 and 7 components, respectively. Two of these components, namely a crustal component and a long-range transport component are common in all three stations. The chemical compositions of these common components are shown to the same within 95% statistical significance interval. Three factors, namely a fertilizer factor, which is highly enriched in NH4+ ion, a sea salt component and an arsenic factor are common in the Mediterranean and Black Sea aerosol but not observed at the Central Anatolia. Other factors found in the regions are specific for that region.
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Industry and traffic related particles and their role in human healthOravisjärvi, K. (Kati) 08 October 2013 (has links)
Abstract
Combustion generated ultrafine particles have been found to be responsible for adverse effects on human health. New emission reduction technologies and fuels will change the composition of particle emissions. It is important to confirm that the new reduction technologies are designed to minimise the adverse health effects.
In this doctoral thesis the potential health effects caused by traffic and industrially generated particles were studied using epidemiological, experimental and in silico studies. The effects of short-term changes in PM2.5 on the respiratory health of symptomatic children living near a steel works were studied to investigate whether specific sources of PM2.5 have the possible health effects. The PM2.5 emission sources were identified: long-range transport, a steel works, soil and street dust and a mechanical engineering works. Significant associations were not found between respiratory symptoms and PM2.5 or the sources markers.
The deposition of traffic-related particles into the human respiratory system was computed using the lung deposition model. Particle size distribution was measured from diesel- and compressed natural gas (CNG)-fuelled busses and an off-road diesel engine under different combustion situations. The majority of the measured traffic-related particle numbers reach the alveolar region of the lungs. There were differences in the deposition of particles when different catalysts, engines or fuels were used. CNG or a diesel particulate filter (DPF) significantly reduced lung exposure to particles. Also physical activity, age and gender affected the deposition of particles. The diesel particles comprised compounds (carcinogenic PAHs, transition metals), which may have the ability to generate reactive oxygen.
This study provides new knowledge how of the emission abatement technologies and fuels affects particle number and their composition, as well health hazards. Cleaner technology (CNG, DPF), emits significantly fewer particles in numbers, especially large particles, but they emit high amounts of small-size particles, which penetrate most easily to the deepest parts of the lungs. In addition, particles from engines with DPF include the largest variety of transition metals and other hazardous compounds compared to combustion systems having different emission after-treatment units. / Tiivistelmä
Palamisprosesseista peräisin olevien ultrapienten hiukkasten on todettu olevan haitallisia ihmisen terveydelle. Uudet pako- ja savukaasujen puhdistusteknologiat ja polttoaineet vaikuttavat hiukkaspäästöihin ja niiden koostumukseen. Uusien menetelmien käytön tulee vähentää hiukkasten mahdollisia terveyshaittoja.
Tässä väitöskirjassa tutkittiin liikenteestä ja teollisuudesta peräisin olevien hiukkasten mahdollisia terveyshaittoja käyttäen epidemiologista, kokeellista ja in silico- menetelmiä. Työssä tutkittiin PM2.5-hiukkasten lyhytaikaisvaihtelun yhteyttä terästehtaan läheisyydessä asuvien hengitystieoireisten lasten terveyteen ja päästölähteiden yhteyttä mahdollisiin terveysvaikutuksiin. Merkittäviä PM2.5-päästölähteitä olivat kaukokulkeuma, terästehdas, maaperä ja tiepöly sekä konepaja. Tutkimuksessa ei havaittu lasten hengitystieoireiden ja PM2.5:n tai päästölähteiden merkkiaineiden välillä merkittävää yhteyttä.
Liikenneperäisten hiukkasten kulkeutumista ihmisen hengitysteihin tutkittiin keuhkodepositiomallilla. Diesel- ja maakaasukäyttöisten (CNG) bussien ja dieselkäyttöisen työkoneen hiukkaskokojakaumat mitattiin eri palamisolosuhteissa. Suurin osa mitatuista hiukkaslukumääristä kulkeutui keuhkojen alveolaaritasolle. Erilaisten katalysaattorien, moottoreiden tai polttoaineiden käytön seurauksena hiukkasten lukumääräpitoisuudet vaihtelivat ja siten hiukkasten kulkeutumisessa hengitysteihin oli eroja. CNG:n tai hiukkassuodattimen (DPF) käyttö vähensi merkittävästi hiukkaslukumääriä ja keuhkojen altistumista hiukkasille. Myös liikunta, ikä ja sukupuoli vaikuttivat hengitysteihin kulkeutuvien hiukkasten määriin. Dieselhiukkaset sisälsivät yhdisteitä (karsinogeeniset PAH:t, siirtymämetallit), jotka tuottavat hengitysteissä reaktiivisia happiradikaaleja.
Tämä tutkimus antaa uutta tietoa päästövähennysmenetelmien ja polttoaineiden vaikutuksista hiukkasten lukumäärään ja koostumukseen sekä hiukkasten terveyshaitoihin. Puhtaamman teknologian käyttö (CNG, DPF) vähentää huomattavasti pakokaasun hiukkasten lukumäärää, etenkin suurten hiukkasten, mutta tuottaa silti suuria määriä pieniä hiukkasia, jotka kulkeutuvat helpommin keuhkojen syvimpiin osiin. Lisäksi moottoreiden hiukkaspäästöt käytettäessä hiukkassuodatinta, sisälsivät enemmän erilaisia siirtymämetalleja ja muita haitallisia aineita verrattuna polttoon, jossa käytettiin muita päästöjen jälkikäsittelymenetelmiä.
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Localisation et contribution de sources acoustiques de navire au passage par traitement d’antenne réduite / Array processing for the localization and the contribution of acoustic sources of a passing-by ship using a short antennaOudompheng, Benoit 03 November 2015 (has links)
Le bruit rayonné par le trafic maritime étant la principale source de nuisance acoustique sous-marine dans les zones littorales, la Directive-Cadre Stratégie pour le Milieu Marin de la Commission Européenne promeut le développement de méthodes de surveillance et de réduction de l'impact du bruit du trafic maritime. Le besoin de disposer d'un système industriel d'imagerie du bruit rayonné par les navires de surface a motivé la présente étude, il permettra aux industriels du naval d'identifier quels éléments d'un navire rayonnent le plus de bruit.Dans ce contexte, ce travail de recherche porte sur la mise en place de méthodes d'imagerie acoustique sous-marine passive d'un navire de surface au passage au-dessus d'une antenne linéaire et fixe au nombre réduit d'hydrophones. Deux aspects de l'imagerie acoustique sont abordés : la localisation de sources acoustiques et l'identification de la contribution relative de chacune de ces sources dans la signature acoustique du navire.Tout d'abord, une étude bibliographique sur le rayonnement acoustique d'un navire de surface au passage est menée afin d'identifier les principales sources acoustiques et de pouvoir ensuite simuler des sources représentatives d'un navire. La propagation acoustique est simulée par la théorie des rayons et intègre le mouvement des sources. Ce simulateur de rayonnement acoustique de navire au passage est construit afin de valider les algorithmes d'imagerie acoustique proposés et de dimensionner une configuration expérimentale. Une étude sur l'influence du mouvement des sources sur les algorithmes d'imagerie acoustique a conduit à l'utilisation d'un algorithme de formation de voies pour sources mobiles pour la localisation des sources et une méthode de déconvolution pour accéder à l'identification de la contribution des sources. Les performances de ces deux méthodes sont évaluées en présence de bruit de mesure et d'incertitudes sur le modèle de propagation afin d'en connaître les limites. Une première amélioration de la méthode de formation de voies consiste en un traitement d'antenne à ouverture synthétique qui exploite le mouvement relatif entre le navire et l'antenne pour notamment améliorer la résolution en basses fréquences. Un traitement de correction acoustique de la trajectoire permet de corriger la trajectographie du navire au passage qui est souvent incertaine. Enfin, la dernière partie de cette thèse concerne une campagne de mesures de bruit de passage d'une maquette de navire de surface tractée en lac, ces mesures ont permis de valider les méthodes d'imagerie acoustique proposées ainsi que les améliorations proposées, dans un environnement réel maîtrisé. / Since the surface ship radiated noise is the main contribution to the underwater acoustic noise in coastal waters, The Marine Framework Strategy Directive of the European Commission recommends the development of the monitoring and the reduction of the impact of the traffic noise. The need for developing an industrial system for the noise mapping of the surface ship have motivated this study, it will allow the naval industries to identify which part of the ship radiates the stronger noise level.In this context, this research work deals with the development of passive noise mapping methods of a surface ship passing-by above a static linear array with a reduced number of hydrophones. Two aspects of the noise mapping are considered: the localization of acoustic sources and the identification of the relative contribution of each source to the ship acoustic signature.First, a bibliographical study concerning the acoustic radiation of a passing-by surface ship is conducted in order to list the main acoustic sources and then to simulate representative ship sources. The acoustic propagation is simulated according to the ray theory and takes the source motion into account. The simulator of the acoustic radiation of a passing-by ship is built in order to validate the proposed noise mapping methods and to design an experimental set-up. A study about the influence of the source motion on the noise mapping methods led to the use of the beamforming method for moving sources for the source localization and a deconvolution method for the identification of the source contribution. The performances of both methods are assessed considering measurement noise and uncertainties about the propagation model in order to know their limitations. A first improvement of the beamforming method consists of a passive synthetic aperture array algorithm which benefits from the relative motion between the ship and the antenna in order to improve the spatial resolution at low frequencies. Then, an algorithm is proposed to acoustically correct the trajectography mismatches of a passing-by surface ship. Finally, the last part of this thesis concerns a pass-by experiment of a towed-ship model in a lake. These measurements allowed us to validate the proposed noise mapping methods and their proposed improvements, in a real and controlled environment.
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