The marine internet of things (MIoT), an increasingly important foundation for ocean development and protection, consists of a variety of marine distributed sensors under water. These sensors of the MIoT have always been highly dependent on batteries. To realize in situ power supply, a flexible seaweed-like triboelectric nanogenerator (S-TENG) capable of harvesting wave energy is proposed in this study. The flexible structure, designed with inspiration from the seaweed structure, processes extensive marine application scenarios. The bending and recovering of the S-TENG structure under wave excitations are converted to electricity. As the output performance increases with the number of parallel connected S-TENG units, an S-TENG system with multiple units could serve for floating buoys, coastal power stations, and even submerged devices. Through the demonstration experiments performed in this study, the flexible, low-cost S-TENG could become an effective approach to achieve a battery independent MIoT.

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As CMOS feature size is reaching atomic dimensions, unjustifiable static power, reliability, and economic implications are exacerbating, thereby prompting for conducting research on new materials, devices, and/or computation paradigms. Within this context, graphene nanoribbons (GNRs), owing to graphene's excellent electronic properties, may serve as basic structures for carbonbased nanoelectronics. In this paper, we make use of the fact that GNR behavior can be modulated via top/back gate contacts to mimic a given functionality and combine complementary GNRs for constructing Boolean gates. We first introduce a generic gate structure composed of a pull-up GNR performing the gate Boolean function and a pull-down GNR performing its complement. Then, we seek GNR dimensions and gate topologies required for the design of 1-, 2-, and 3-input graphene-based Boolean gates, validate the proposed gates by means of SPICE simulation, which makes use of a non-equilibrium Green's function Landauer formalism based Verilog-A model to calculate GNR conductance, and evaluate their performance with respect to propagation delay, power consumption, and active area footprint. Simulation results indicate that, when compared with 7 nm FinFET CMOS counterparts, the proposed gates exhibit 6× to 2 orders of magnitude smaller propagation delay, 2 to 3 orders of magnitude lower power consumption, and necessitate 2 orders of magnitude smaller active area footprint. We further present full adder (FA) and SRAM cell GNR designs, as they are currently fundamental components for the construction of any computation system. For an effective FA implementation, we introduce a 3-input MAJORITY gate, which apart of being able to directly compute FA's carry-out is an essential element in the implementation of error correcting codes codecs, which outperforms the CMOS equivalent carry-out calculation circuit by 2 and 3 orders of magnitude in terms of delay and power consumption, respectively, while requiring 2 orders of magnitude less area. The proposed FA exhibits 6.2× smaller delay, 3 orders of magnitude less power consumption, while requiring 2 orders of magnitude less area, when compared with the 7 nm FinFET CMOS counterpart. However, because of the effective carry-out circuitry, a GNRbased n-bit ripple carry adder, whose performance is linear in the carry-out path, will be 108× faster than an equivalent CMOS implementation. The GNR-based SRAM cell provides a slightly better resilience to dc-noise characteristics, while performance-wise has a 3.6× smaller delay, consumes 2 orders of magnitude less power, and requires 1 order of magnitude less area than the CMOS equivalent. These results clearly indicate that the proposed GNR-based

Loss reduction to improve the power efficiency in active integrated antenna (AIA) is a key design drive. This paper first analyzes the loss mechanism in a convention AIA structure. A new integration scheme of a GaN power amplifier (PA) transistor with an antenna without using any output matching network (OMN) and harmonic tuning network (HTN) is then proposed to construct a seamlessly integrated AIA. This is achieved by a novel design of a slot antenna with optimized input impedance at its fundamental frequency as well as for harmonic tuning, which essentially absorbs the OMN and HTN functions in the conventional Class-F power amplifier design. By eliminating these passive networks between the transistor and the antenna, the associated insertion and mismatch losses as well as the overall circuit size are reduced. For verification, two prototypes are designed, fabricated and measured, one with the integrated design and the other with a conventional design for comparison. Both AIAs operate between 3.4 and 3.6 GHz. Experimental results show that the power-added efficiency (PAE) of the seamlessly integrated AIA is over 52% within the operating band. Compared with the conventional cascaded design of a PA and an antenna, the PAE is improved by 14.2%. INDEX TERMS Amplifier integrated antenna, active antenna, Class-F power amplifier, loss reduction, seamless integration.

The entire education system, from elementary school to higher education, distorted during the lockdown period. The latest 2019 coronavirus disease (COVID-19) is not only recorded in China, but also globally. This research is an account of the online teaching paradigm assumed in the teaching method by most of universities in China and subsequent tests over the course. It looks forward to offering resources rich in knowledge for future academic decision-making in any adversity. The aim of this research paper is to explain the prerequisites for online education and teaching during the COVID-19 pandemic and how to effectively turn formal education into online education through the use of virtual classrooms and other main online instruments in an ever-changing educational setting by leveraging existing educational tools. The paper uses both quantitative and qualitative research approaches to analyses the views of online teachers and students on the learning regime, with specific attention to the online learning regime implementation process. In the midst of the COVID-19 outbreak, the purpose of this article is to provide an in-depth overview of online learning. These activities took place during a time of isolation, including the creation of a link between the process of change management and the online learning process in the education system to tackle current issues of academic interference and, however, the re-establishment of educational practice and debate as a normal system of procedural education.