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Tire/road interaction is one of the main causes of traffic noise. This generates health, social, and environmental issues. Bituminous mixtures containing crumb rubber, CR, and with low-nominal maximum aggregate size, NMAS, can be used to mitigate the aforementioned issues in both the short and long period. The main objective of the study presented in this paper is to investigate the variation of volumetric, surface, mechanical, and acoustical properties of friction courses due to the presence of treated and un-treated CR. Low-noise mixtures were designed during the ongoing project "E-VIA" (LIFE18 ENV/IT/000201) and were used to pave a street in Florence. In the laboratory, samples were created using the Superpave Gyratory Compactor (AASHTO T-312, UNI EN 12697-31). Specimens with NMAS=6 mm and bitumen in the range 6-7% were used as a reference. Other two sets of specimens were created adding treated and un-treated CR (dry method). Results show how the different composition affects the properties and performance of the mixtures under investigation. Future studies will include the comparison between the in-lab produced specimens (herein analyzed) and the cores extracted from the aforementioned street. [ABSTRACT FROM AUTHOR]

Vehicles that collect and transport household waste are equipped with complex systems that perform the loading of the waste from the stationary collection containers, take over and pre-compact of material, compaction in the body of the structure and finally the landfill of the collected waste. Of all these operations, the compaction process is by far the most mechanically demanding. In this paper, the structural analysis of the compactor plate from a garbage truck is presented. In the first stage it was carried out parametric modelling of the assembly composed of compactor plate, counter pressure plate, the back of the garbage truck and to be compacted material. After assembly, the dynamic simulation of the compaction process in the garbage truck was performed, and the compaction mechanical stresses for the compactor plate were loaded in the Simulation module of the SolidWorks 2016 program. Here the finite element analysis was performed, resulting in the value and dispersion of the equivalent stresses (calculated by von Mises criterion), displacements and relative deformations of compactor plate from the analysed garbage truck. [ABSTRACT FROM AUTHOR]

An X-masking scheme prevents unknown (X) values from shifting into an output response compactor, whereas an X-canceling MISR methodology allows X's to enter the compactor, but then cancels them out through selective XORing. However, both approaches require significantly high volume of the control bits to remove X values to generate X-free output signatures. This paper proposes a method to reduce the control bit overhead by combining X-masking and X-canceling methodologies and exploiting the fact that unknown values tend to have high correlation in the scan cells. In this paper, correlation is considered across whole patterns in order to enhance reuse of control bits. The proposed hybrid method of X-canceling and X-masking reduces test time without losing fault coverage. The experimental results show that the proposed method significantly reduces control bits and test time compared to a conventional X-canceling MISR methodology. [ABSTRACT FROM AUTHOR]