Abstract. This paper presents the results of a series of laboratory measurements, carried out to study how the groundpenetrating radar (GPR) signal is affected by moisture variation in wood material. The effects of the wood fibre direction, with respect to the polarisation of the electromagnetic field, are investigated. The relative permittivity of wood and the amplitude of the electric field received by the radar are measured for different humidity levels using the direct-wave method in wide angle radar reflection configuration, in which one GPR antenna is moved while the other is kept in a fixed position. The received signal is recorded for different separations between the transmitting and receiving antennas. Dielectric constants estimated from direct waves are compared to those estimated from reflected waves: direct and reflected waves show different behaviour when the moisture content varies, due to their different propagation paths.
Abstract. This paper presents the results of a series of laboratory measurements carried out to study how the Ground Penetrating Radar (GPR) signal is affected by moisture variation in wood material. The effects of the wood fiber direction, with respect to the polarisation of the electromagnetic field, are investigated. The relative permittivity of wood and the amplitude of the electric field received by the radar are measured for different humidity levels, by using the direct-wave method in Wide Angle Radar Reflection configuration, where one GPR antenna is moved while the other is kept in a fixed position. The received signal is recorded for different separations between transmitting and receiving antennas. Direct waves are compared to reflected waves: it is observed that they show a different behaviour when the moisture content varies, due to their different propagation paths.
Radon exposure in the workplace is one of the main exposures to the population after that in dwellings. These workplaces are generally at the ground and/or first floor, where radon concentration is generally higher than at upper ones. This study deals with the measurements of indoor radon concentration in several workplaces located in different geological conditions. Measurements of indoor radon concentration have been carried out using passive bare detectors based on CR -39 in 50 workplaces, including one site at the Centre of Applied Nuclear Physics, Tirana. According to the principles of the methodology, the radon passive detectors have been located inside the workplaces for three months exposure, allowing the calculation of average values, which represent much better the true values of the radon concentration inside of a closed environment. The exposure time of detectors was performed during period January-April 2014. According to the assessment made by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), radon in the natural environment constitutes about 50% of the human exposure to natural radiation or 1.2 mSv/year. The measurements were used to calculate the effective dose due to the radon contribution (mSv/y). Based on the results of the measurements, the minimum value of the radon concentration found is 53 Bq/m 3 to 400 Bq/m 3 in workplaces, while the reference levels are 300 Bq/m 3 . Around 90% of the radon concentration values are within reference levels. The results of this study represent a variation of radon concentration related to geological composition. More detailed studies are needed in areas with different geology and construction materials for a better spatial distribution of radon concentration, particularly in public places.
Prespa Lake Basin is a transboundary basin that's shared between Albania-Greece-FYROM. This region has a very complicated geology. The main aquifer systems are developed in carbonate rocks (karst aquifers) crossing international borders (transboundary aquifers). A map was constructed in GIS environment
<p>The transboundary aquifers are of utmost importance to sustain water supply in present days. The exploitation of these aquifers has to be only in a sustainable and rational way, in order to sustain the quantity and quality of the aquifers' groundwater. A transboundary aquifer is developed in karstified limestones between the lakes Great Prespa (shared between North Macedonia, Albania, and Greece ) and Ohrid (shared between North Macedonia and Albania). The karst mountainous area is characterized by the presence of numerous crevices, sinkholes, as surface forms, and caves, canals, etc., as underground forms. The elevation of Prespa Lake is about 153 m higher than that of Ohrid Lake, and the two lakes represent a common hydraulic system, protected by international conventions. Prespa Lake is characterized by a continuous decline in water level during the last decades. The transboundary karstic aquifer is a complex system, discharging through numerous karstic springs (e.g., Saint Naum, Tushemisht, etc.), and operating as a hydrocollector and hydroconductor between the lakes. The aquifer is vulnerable to external pollution, as well as to climate changes affecting the lakes&#8217; ecosystems. Agriculture, livestock, and tourism are the main activities in the wider area.</p><p>The DPSIR (Driver-Pressure-State-Impact-Response) model, adopted by European Environmental Agency, was applied in GIS context, in order to study and analyze the main causes of pressures and to optimize the measures for integrated aquifer management. In addition, the aim of DPSIR technique is the correlation of the driving forces and pressures with the present status of the complex hydraulic system and finally to optimize the aquifer management. The major driving forces that affect the Prespa-Ohrid basin are the irrigated agriculture, the livestock, the tourism development, and population growth. The main pressures are the overexploitation of the aquifer, water pollution, and the decline of the water level of Lake Prespa.</p><p>Based on the results of DPSIR, a set of measures and appropriate policy responses are proposed. Finally, DPSIR is a valuable tool for local authorities and administrators in order to plan and implement strategies for integrated and sustainable management of the transboundary karst aquifer and its dependent ecosystems.</p>
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