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In this paper, an ultra-thin logo antenna (LGA) operating in multiple frequency bands for Internet of Vehicles (IoVs) applications was proposed. The designed antenna can cover five frequency bands, 0.86–1.01 GHz (16.0%) for LoRa communication, 1.3–1.36 GHz (4.6%) for GPS, 2.32–2.71 GHz (16.3%) for Bluetooth communication, 3.63–3.89 GHz (6.9%) for 5G communication, and 5.27–5.66 GHz (7.1%) for WLAN, as the simulation indicated. The initial antenna started with a modified coplanar waveguide (CPW)-fed circular disk monopole radiator. To create extra current paths and further excite other modes, the disk was hollowed out into the shape of the car logo of the Chinese smart EV brand XPENG composing four rhombic parasitic patches. Next, four triangular parasitic patches were inserted to improve the impedance matching of the band at 5.6 GHz. Finally, four metallic vias were loaded for adjusting resonant points and the return loss reduction. Designed on a flexible substrate, the antenna can easily bend to a certain degree in complex vehicular communication for IoV. The measured results under horizontal and vertical bending showed the LGA can operate in a bending state while maintaining good performance. The proposed LGA addresses the issue of applying one single multi-band antenna to allow vehicles to communicate over several channels, which relieves the need for a sophisticated antenna network. [ABSTRACT FROM AUTHOR]

The influence of nanomechanical tensile behavior on electron transport is especially interesting for ultra-thin SiC nanowires (NWs) with different diameters. Our studies theoretically show that these NWs can hold stable electron transmission in some strain ranges and that stretching can enhance the electron transmission around the Fermi level (EF) at the strains over 0.5 without fracture for a single-atom SiC chain and at the strains not over 0.5 for thicker SiC NWs. For each size of SiC NW, the tensile strain has a tiny effect on the number of device density of states (DDOSs) peaks but can increase the values. Freshly broken SiC NWs also show certain values of DDOSs around EF. The maximum DDOS increases significantly with the diameter, but interestingly, the DDOS at EF shows little difference among the three sizes of devices in the late stage of the stretching. Essentially, high electron transmission is influenced by high DDOSs and delocalized electronic states. Analysis of electron localization functions (ELFs) indicates that appropriate tensile stress can promote continuous electronic distributions to contribute electron transport, while excessively large stretching deformation of SiC NWs would split electronic distributions and consequently hinder the movement of electrons. These results provide strong theoretical support for the use of ultra-thin SiC NWs in nano-sensors for functional and controllable electronic devices. [ABSTRACT FROM AUTHOR]

This article presents the design of wide-band, ultra-thin, and multi-purpose polarization converter utilizing metasurface for C-, X-, and Ku-band applications. Having a topology on a FR-4 substrate with metasurface metallic patterns on the front and an all-metallic surface finish on the back, the unit cell of converter design has symmetry in the x − y plane with unique features of having both linear polarization (LP) and circular polarization (CP) property. While the polarization conversion ratio (PCR) of converter in normal incidence case is more than 90% in three different frequency bands of 6.46–6.78 GHz, 10.52–11.85 GHz, and 16.49–17.37 GHz, it shows linear-to-linear polarization feature and a linear-to-circular polarization feature with left-handed circular polarization (LHCP) for the frequency range between 7.28 and 9.40 GHz and right-handed circular polarization (RHCP) for the frequency range between 13.38 and 15.19 GHz. It is also seen that the converter has a PCR value of around 90% for oblique incidence case with incidence angles up to 45 ° . Extensive simulations have been conducted to prove the performance of suggested converter with the aid of a commercially-available simulation platform, called CST Microwave Studio. The advantages of suggested polarization converter are low-cost, wide-band, ultra-thin, and having both LP and CP conversion in C-, X-, and Ku-bands. [ABSTRACT FROM AUTHOR]

In this study, an innovative fabrication method called rolling-slitting forming, which forms ultra-thin diamond blades, was presented for the first time. Furthermore, the feasibility of the rolling-slitting forming method when applied to silicon carbide wafer dicing blades was investigated; moreover, the cold-pressing blade samples were manufactured through the conventional process under the same sintering conditions to compare and analyze the manufacturing efficiency, organization and performance. The results show that the new method achieves high-precision and low-thickness dicing blades through continuous production without molds—with the thinnest blades being 0.048 mm thick. Furthermore, the rolling-slitting blade has a unique multiporous heat-conductive matrix structure and in-situ generated amorphous pyrolytic carbon, which can reduce the dicing resistance and contribute to a better cutting quality. In addition, the effects of the dicing parameters on SiC were investigated by using indications of spindle current, dicing chipping size and kerf width during the high dicing process. For a dicing depth of 0.2 mm, the ideal performance of dicing SiC with an ultra-thin blade was achieved at a spindle speed of 22,000 rpm and a feed rate of 5 mm/s. This research provides a new idea for the manufacturing of dicing blades, which can satisfy the demand for ultra-narrow dicing streets of high integration of ICs. [ABSTRACT FROM AUTHOR]

We demonstrate the growth of ultra-thin (~5 nm) indium ytterbium oxide (In-Yb-O) thin film using a simple vacuum-free aqueous solution approach for the first time. The influences of Yb addition on the microstructural, chemical, optical, and electrical properties of In2O3 are well investigated. The analyses indicate that Yb dopant could suppress oxygen vacancy defects effectively owing to the lower standard electrode potential, lower electronegativity, and stronger metal-oxide bond strength than that of In. The optimized In-Yb-O thin-film transistors (TFTs) exhibit excellent electrical performance (mobility of 8 cm2/Vs and on/off ratio of ~108) and enhanced stability. The triumph of In-Yb-O TFTs is owing to the high quality In2O3 matrix, the remarkable suppressor of Yb, and the nanometer-thin and atomically smooth nature (RMS: ~0.26 nm) of channel layer. Therefore, the eco-friendly water-induced ultra-thin In-Yb-O channel provides an excellent opportunity for future large-scale and cost-effective electronic applications. [ABSTRACT FROM AUTHOR]

In order to make a comprehensive comparison between ultra-thin hot rolled low carbon steel (LC) and extra low carbon steel (ELC) produced by endless roll technology and explain the differences, a detailed investigation into the microstructural characterization, characteristics of cementite and precipitates, mechanical properties, internal friction peaks, texture characterization by an X-ray powder diffractometer and electron backscatter diffraction, and formability including earing behavior, hole expanding ratio and V-shaped bending properties was carried out with different carbon content for 1.0 mm thickness ultra-thin hot rolled strip produced in endless strip production line. The experimental results indicate that the microstructure of both is composed of multi-layer areas with different grain sizes and thicknesses, the strength and elongation of LC are higher than that of ELC, but the content of solid solution carbon atoms and r of ELC are higher than that of LC, at the same time, the formability of ultra-thin strip ELC is better than that of LC mainly related to the content of {hkl} <110> and {111} <112> of ELC was higher than those of LC. The mechanical and formability properties of ultra-thin hot rolled strip by endless roll technology can meet the requirements of replacement cold rolled strip by hot rolled strip. [ABSTRACT FROM AUTHOR]

The friction surfacing technique is an advanced method for creating coatings of various materials onto the surface of a similar or dissimilar material substrate. In this method, there is no external source of heat energy, and all the heat energy required in this method is generated by friction. In this paper, a novel method of friction surfacing from the side of the consumable tool is introduced. The most significant difference in this technique is that material transfer will occur from the radial surface of the consumable tool as opposed to the end of the tool as in conventional friction surfacing. In lateral friction surfacing, the side of the rotating consumable tool is pressed against the substrate surface, which generates frictional heating and shear forces at the interface between tool and substrate. A layer of tool material is transferred from the consumable rod to the substrate surface as the tool moves across. In this study, 6063 aluminum alloy and AISI 1018 carbon steel are used as the materials of consumable tool and substrate, respectively. The impact of process factors, surface roughness values, tool mass loss, and deposition thickness are discussed in detail. The experimental results of this study reveal that lateral friction surfacing produces a very smooth ultra-thin deposition with full coverage, with coating layers with roughness values in the order of 1 µm. Additionally, there is no flash formed in this technique which reduces material consumption. Moreover, temperatures at the interface between the consumable tool and workpiece were measured to be lower than for that in friction surfacing from the end of the tool, which is beneficial for the metallurgical characteristics of the deposited material. [ABSTRACT FROM AUTHOR]