Air pollution mapping : relationship between satellite- made observations and air quality parameters

International audienceThe mapping of air quality over the city of Strasbourg and its vicinity requires an increase of the number of measurements aiming at spatializing information about air pollutants concentrations. A methodology based on a multisource approach for mapping air pollutants concentrations over the city was presented in previous communications. One step of the methodology is the estimation of pollutants concentrations by remote sensing techniques. This paper investigates the strength of linear relationship between satellite-made observations and air quality parameters. Multidate correlations were calculated between reflectances measured by Landsat satellite and measurements of the various pollutants. Those measurements are concentrations of pollutants on a daily average basis, or for the time of image acquisition, or on a basis of average of several hours before the image acquisition. The results add evidence on linear correlation between air quality parameters and satellite measurements not only in thermal infrared range but also in the infrared range

Comparision of Two Thermal Decomposition Offset Printing Plates

The aim of our research was to investigate two digital plates based on the same type of thermal sensitive coating produced by different manufactures and compare their quality, run length, ecological and economical aspects and user experience in the offset press. It was found out that with both plates the same quality of prints was attained according to the measurements of tone values on the plates and prints. The spectrophotometric measurements also showed that the prints were almost identical, except for minor differences in lightness. The microscopic image analysis showed that one plate had finer graining and thereby gave better and more accurate representation of half-tone dot and this plate was also more environmentally–friendly with lower consumption of chemicals for the plate developing, more durable with longer run lengths and as well more economical and user–friendly. The obtained results were useful for the offset printing company in its choosing the better thermal plate with reduced production costs

Negative exponential behavior of image mutual information for pseudo-thermal light ghost imaging: Observation, modeling, and verification

When use the image mutual information to assess the quality of reconstructed image in pseudo-thermal light ghost imaging, a negative exponential behavior with respect to the measurement number is observed. Based on information theory and a few simple and verifiable assumptions, semi-quantitative model of image mutual information under varying measurement numbers is established. It is the Gaussian characteristics of the bucket detector output probability distribution that leads to this negative exponential behavior. Designed experiments verify the model.Comment: 13 pages, 6 figure

Inflow and Loadings from Ground Water to the Great Bay Estuary, New Hampshire

This final report presents the results of a study to evaluate groundwater inflow and nutrient loadings to the Great Bay Estuary, New Hampshire. The evaluation of inflow was accomplished independently by two methods: one, used thermal imagery, and the other, piezometric mapping. The thermal imagery method assessed groundwater that was observed to discharge within the intertidal zone of an inland estuary. The groundwater piezometric mapping method used bedrock wells around the bay to create an overall piezometric map of the near-bay area. Groundwater discharge was evaluated with respect to flow, concentration, and ultimately nitrogen loading to coastal waters. The results represent a snapshot for these variables, examined by a thermal infrared aerial survey in the spring of 2000, and water quality, specific discharge, and piezometric surface maps in the summer of 2001. Monitoring wells upgradient of the Great Bay were analyzed for nitrogen as an indicator of potential discharge source waters. Total groundwater discharge to the estuary was calculated as 24.2 cubic feet per second (cfs) with an average of 0.81± 0.89 mg dissolved inorganic nitrogen (DIN)/L, with a maximum value of 2.7 mg DIN/L (n=20). Nutrient concentrations, averaging 0.83± 1.34 mg DIN/L, with a maximum value of 10.2 mg DIN/L, were observed in upgradient bedrock groundwater analyzed from 192 wells. Nutrient loading was calculated to be 19.3±21.2 tons of N per year for the total Great Bay Estuary, covering nearly 144 miles of shoreline. The groundwater derived nutrient loading accounts for approximately 5% of the total non-point source load to the estuary. The thermal imagery method was found to be an effective and affordable alternative to conventional groundwater exploration approaches

Use of a drone equipped with microthermal sensors to estimate the quality of the atmosphere for astronomical observation

A drone was used to obtain thermal profiles to estimate atmospheric turbulence for the purposes of astronomical observation. The first 150m of height were studied in two areas in the southeast of the Iberian Peninsula. The preliminary results have validated the use of drones as a suitable means of transport for obtaining microthermal measurements. We have also assessed the influence of the planetary boundary layer on the quality of the image for astronomical purposes. In future research, we intend to check these measurements with fixed microthermal sensors installed in meteorological towers.Departamento de Análisis Geográfico Regional y Geografía Física de la Universidad de Granad