The goal of this study was to develop a prototype for harvesting thermoelectric energy from asphalt pavement roadways. This emerging research field encompasses technologies that capture the existing thermal energy in pavements to generate electricity without depleting natural resources. In lower latitudes, such as south Texas, the asphalt pavement surface temperature in the summer can reach 55°C because of solar radiation. Soil temperatures below the pavement, however, are roughly constant (i.e., 27°C to 33°C) at relatively shallow depths (150 mm). This thermal gradient between the surface temperature and the pavement substrata can be used to generate electrical power through thermoelectric generators (TEGs). The proposed prototype collects heat energy from the pavement surface and transfers the energy to a TEG embedded in the subgrade at the edge of the pavement shoulder. Evaluation of this prototype was carried out through finite element analysis, laboratory testing, and field experiments. The results suggest that the 64- × 64-mm TEG prototype can generate an average of 10 mW of electric power continuously over a period of 8 h in the weather conditions in south Texas. Scaling up this prototype by using multiple TEG units could generate sufficient electricity to sustainably power low-watt LED lights and roadway and traffic sensors in off-grid, remote areas.

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The search for genuine two-particle dynamical correlations among the pions produced in 16 O-AgBr interactions at 60 AGeV and 32 S-AgBr interactions at 200 AGeV (super proton synchrotron data) has been carried out by the method of normalized factorial cumulant moments in pseudo-rapidity (η), azimuthal angle (φ) and two-dimensional anisotropic (η-φ) phase space. The analysis reveals the presence of genuine two-particle dynamical correlations among the pions in 16 O-AgBr and 32 S-AgBr interactions in both one and two dimensions. Stronger correlation has been observed in higher dimensional space. Correlations between the pions are found to decrease with the increase of projectile mass and energy. Experimental results have been compared with the FRITIOF data sample in the pseudo-rapidity space. In azimuthal angle space, events simulated by generating random numbers (Monte Carlo Simulation) have been used for the purpose of comparison. The FRITIOF data and the data of the simulated interactions have failed to reproduce the experimental results. The experimental results have also been compared with the event sample generated by the UrQMD model in both pseudo-rapidity and azimuthal angle space. Like the FRITIOF model, the UrQMD model is also unable to replicate the experimental results. The variation of normalized cumulant moment (K 2 ) against the number of bin M has been fitted with a function K 2 = aM b in both one and two dimensions. No fitting of this kind has been possible in the case of the FRITIOF data, UrQMD data and the MC simulated data. * This work is financially supported by University Grants Commision, Govt. of India (Sanction No PSW-044/11-12).

The multiplicity fluctuations of the produced pions were studied using scaled variance method in 16 O-AgBr interactions at 2.1 AGeV, 24 Mg-AgBr interactions at 4.5 AGeV, 12 CAgBr interactions at 4.5 AGeV, 16 O-AgBr interactions at 60 AGeV and 32 S-AgBr interactions at 200 AGeV at two different binning conditions. In the first binning condition, the rapidity interval was varied in steps of one centring about the central rapidity until it reached 14. In the second case, the rapidity interval was increased in steps of 1.6 up to 14.4. Multiplicity distributions and their scaled variances were presented as a function of the dependence on the rapidity width for both the binning conditions. Multiplicity fluctuations were found to increase with the increase of rapidity interval and later found to saturate at larger rapidity window for all the interactions and in both the binning conditions. Multiplicity fluctuations were found to increase with the energy of the projectile beam. The values of the scaled variances were found to be greater than one in all the cases in both the binning conditions indicating the presence of correlation during the multiparticle production process in high-energy nucleus-nucleus interactions. Experimental results were compared with the results obtained from the Monte Carlo simulated events for all the interactions. The Monte Carlo simulated data showed very small values of scaled variance suggesting very small fluctuations for the simulated events. Experimental results obtained from 16 O-AgBr interactions at 60 AGeV and 32 SAgBr interactions at 200 AGeV were compared with the events generated by Lund Monte Carlo code (FRITIOF model). FRITIOF model failed to explain the multiplicity fluctuations of pions emitted from 16 O-AgBr interactions at 60 AGeV for both the binning conditions. However, the experimental data agreed well with the FRITIOF model for 32 S-AgBr interactions at 200 AGeV.

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