In this research article, an organic polymer based polypyrrole (Ppy) composite material has been synthesized and analyzed for the design and fabrication purposes of a fast-responsive, highly sensitive, and an economical resistive-type novel humidity detection sensor. This humidity sensor most suitably serves the purpose for industrial humidity (i.e., values ranging from low to high) detection applications. First, a polypyrrole composite material (a mixture of polypyrrole, polypyrrole-NiO, polypyrrole-CeO₂, and polypyrrole-Nb₂O₅) has been synthesized by chemical oxidative polymerization method, and then is treated at various temperatures, i.e., 100, 150 and 200 °C, respectively. After this treatment, the synthesized samples were then characterized by using FTIR, SEM, and DTA/TGA techniques for analyzing humidity sensing properties. The polypyrrole samples with the best morphological structure and properties were then incorporated on interdigitated electrodes. For the fabrication purposes of this thin film structure, at first a few drops of polyvinyl alcohol (PVA) were placed over interdigitated electrodes (IDE) and then the synthesized polypyrrole composite was uniformly deposited in the form of a thin film over it. The plots show that this is a good resistive-type humidity detection device for the relative humidity range of 30% to 90%. The response and recovery times of this newly fabricated humidity sensor were reported to be the same as 128 s at room temperature. Additionally, the stability and the repeatability response behavior of this Ppy sensor were verified up to five cycles of multiple repetitions. This presents an excellent stability and repeatability performance of the sensor. Furthermore, the capacitances versus humidity response and recovery properties of the designed sensor were studied too. This illustrates an excellent capacitive verses humidity response and shows a linear and an active behavior. Lastly, the experimental result proves that polypyrrole composite thin film shows a reasonable best performance up to a temperature of 100 °C.

Nowadays, it is relatively common to follow traffic rules, such as wearing a helmet and fastening seat belts, but accidents are increasing daily. Concerned with these traffic safety issues, this study focuses on the psychology of bike riders. First, a brief questionnaire is prepared by filtering some significant traffic safety factors. For effective results and analysis, a questionnaire survey (i.e., interviews) is conducted across different road junctions in Sargodha, Pakistan, with the assistance of traffic police. The data is analyzed through a multiple regression analysis, forming a different model for effective outcomes. A risk compensation hypothesis theory is considered; based on the questionnaire designed and the input received from participants, three models are developed with significant variables. The first two models evaluate the physical impact of helmets on riders/cyclists, while the third observes changes (in terms of obeying traffic laws) in behavior when wearing a helmet. It has been observed that cyclists wearing helmets may follow zigzag patterns while wearing helmets, which may cause accidents. Moreover, it has been observed that cyclists wearing helmets may be more responsible regarding traffic rules. These problems should be considered in creating effective traffic safety campaigns and policy making.

AC-fed railway traction drives suffer from pulsating input power because of the single-phase width modulation rectifier at the front end. To restrain DC voltage fluctuations a large DC-link capacitance is used which is expensive, bulky, and have a lifetime limit. However, a converter current control loop inherently involves a delay in supplying required current which makes DC-link current unbalance due to which DC-link voltage variations occur. This paper addresses a control method of reducing the size of the DC-link capacitors. The main idea is to utilize the load power as a feed-forward compensation term which is adjusting the reference current and improving the dynamic response of the rectifier. Theoretically, this control strategy is effective in regulating the DC voltage level, even though the DC-link capacitor is arbitrarily small and load varies abruptly. The effectiveness of this strategy has been verified by detailed simulation studies.