Vehicle passage sensors provide important information for the traffic monitoring system. Despite missing a large amount of passing vehicle data, inductive loop sensors are one of the most commonly used detectors. Here, we introduce a sensor based on piezoelectric poly(vinylidene fluoride) (PVDF) composite fibers through which vehicle passage can be precisely identified. Loaded with 3 wt % of a TiO 2 −ZnO hybrid filler, the PVDF composite fibers benefit from the high β-phase crystallinity of 92%, demonstrating a 13fold increase in the generated voltage compared to the pristine PVDF fiber. On the basis of a corresponding piezoelectric nanogenerator (PNG) coupled with a circuit and a microcontroller, we have developed a sensor for vehicle passage monitoring. The designed sensor that has been installed on a speed bump successfully detects the passing vehicle tires, presenting a significant step toward traffic monitoring.

This paper presents a new high speed 5-2 compressor. It is designed based on a new truth table which leads to a simple structure. Also, the driving problems are reduced. Due to the similar paths from inputs to the outputs, there will be no need for extra buffers in low latency paths to equalize the delays and the power dissipation is decreased. Furthermore, by use of full swing logics, the speed of cascaded operations is enhanced. The latency of proposed design is 440 ps.

No abstract

Polyacrylonitrile (PAN) fibers with unique properties are becoming increasingly important as precursors for the fabrication of carbon fibers. Here, we suggest the preparation of porous PAN composite fibers to increase the homogeneity and thermal stability of the fibers. Based on the thermodynamics of polymer solutions, the ternary phase diagram of the PAN/H2O/Dimethylformamide (DMF) system has been modeled to introduce porosity in the fibers. Adding a conscious amount of water (4.1 wt.%) as a non-solvent to the PAN solution containing 1 wt.% of graphene oxide (GO), followed by wet spinning, has led to the preparation of porous composite fibers with high thermal stability and unique physicochemical properties. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) results elucidate that PAN/GO/H2O porous composite fibers have a higher thermal decomposition temperature, increased residual weight, reduced heat release rate, and higher crystallinity in comparison with the pristine PAN fibers, being a promising precursor for the development of high-performance carbon fibers. The results show a promising application window of the synthesized PAN fibers in electronic and electrochemical devices.

No abstract