Micromixers are the microfluidic devices able to rapidly mix more than two liquids, with low pressure drop and high mixing efficiency (εmixing). In this study, the effect of Reynolds number ratio (Rer) and aspect ratio (AR) of heart-like biometric micromixer applied would be investigated by a numerical simulation and experimental confirmation. Results show that the heart-like biometric micromixer resulting from the coupling effect of the split and recombination (SAR) and biometric design can produce a high mixing efficiency, low pressure drop and short mixing path under a case of low Reynolds number. Two dimensional results also find that a flow mixing efficiency of εmixing=0.89 and an optimal mixing index of Midx=115 could be achieved at a flow condition of Rer=0.75 and Re2=0.1 of the middle-inlet channel I2. In additional, the three dimensional results indicate that a high flow mixing efficiency of εmixing=0.84 and the lowest pressure drop of 164.2 Pa was obtained at the flow conditions of Rer=0.9 and AR=10 when the middle-inlet channel I2 was Re2=0.1. These findings will be useful to improvement the efficiency for micromixcers of biometric design in the future.

With the low latency, high transmission rate, and high reliability provided by the fifth-generation mobile communication network (5G), many applications requiring ultra-low latency and high reliability (uRLLC) have become a hot research topic. Among these issues, the most important is the Internet of Vehicles (IoV). To maintain the safety of vehicle drivers and road conditions, the IoV can transmit through sensors or infrastructure to maintain communication quality and transmission. However, because 5G uses millimeter waves for transmission, a large number of base stations (BS) or lightweight infrastructure will be built in 5G, which will make the overall environment more complex than 4G. The lightweight infrastructure also has to be considered together. For these reasons, in 5G, there are two mechanisms for handover, horizontal, and vertical handover; hence, it must be discussed how to handle handover to obtain the best performance for the whole network. In this paper, to address handover selection, we consider delay time, energy efficiency, load balancing, and energy consumption and formulate it as a multi-objective optimization (MOO) problem. At the same time, we propose the handover of the mobile management mechanism based on location prediction combined with heuristic algorithms. The results show that our proposed mechanism is better than the distance-based one for energy efficiency, load, and latency. It optimizes by more than about 20% at most.

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A TB88 step-up circuit for minor thermoelectric signal, induced by chip "TEG-12703", is developed in this study. Here several hundred microvolts could be created if finite differential temperature on the side surface of thermoelectric chip is imposed. Such small amount of voltage induced seems to be not adequate to meet the demand of commercial benefit unless a step-up circuit to augment the electrical potential is specified. In this article, a step-up circuit of TB88 IC with thermoelectric-electricity transforming efficiency 55~65% has been carried out and successfully boosted the voltage from 0.5 V to 5V. That not only holds an extra 40 % advantage of power delivery, compared to the performance accessed from commercial amplified device " CE8301" (Figure 1), but also significantly reduces the experimental cost required and easily accessed for local laboratory.