A high responsivity and controllable recovery ultraviolet (UV) photodetector based on a tungsten oxide (WO₃) gate AlGaN/GaN heterostructure with an integrated micro-heater is reported for the first time. The WO₃nanolayer was deposited by physical vapor deposition (PVD) for deep UV absorption and the micro-heater was integrated for chip level heating and cooling. Our device when exposed to UV wavelength exhibits a high responsivity of 1.67 × 10⁴A W⁻¹at 240 nm and a sharp cut-off wavelength of 275 nm. More importantly, the persistent photoconductivity (PPC) effect can be eliminated by a novel method, mono-pulse heating reset (MHR), which consists in applying an appropriate pulse voltage to the micro-heater right after the removal of the UV illumination. The recovery time was reduced from hours to just seconds without reducing the high responsivity and stability of the photodetector. The UV detection, high responsivity, high stability, controllable recovery process and low production cost of GaN-based photodetectors make these devices extremely attractive for several applications, such as fire detection and missile and rocket warning.

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The 11 papers in this special section focus on sensing and perception systems for intelligent manufacturing. This new industrial revolution calls for solutions to embedded intelligence, networked environment, interaction, autonomous, and high performance computing. The manufacturing industry is at the center of this wave of innovation with sensing and perception in focus. The papers included in this section examine the methodologies developed are all based on processing data generated by complex sensing devices acting on certain kind of physical fields, such as vision and temperature field, in order to render 2-D or 3-D information of fields. This kind of field sensing and perception development is the key to facilitate the intelligent operation of manufacturing systems in practices.@en

The relation between the microstructure and the magnetic properties of Fe₂P-type (Mn,Fe)₂(P,Si,B) based materials has been systematically investigated by changing the annealing temperature and time. X-ray diffraction, Scanning Electron Microscopy and Energy Dispersive X-ray Spectroscopy measurements show that the alloys contain the main Fe₂P-type phase and two impurity phases of (Fe,Mn)₅Si₃-type and Fe₂MnSi-type. Boron appears to facilitate the formation of the Fe₂P-type phase during the arc-melting progress. Upon increasing the annealing temperatures from 1123 to 1423 K, the Curie temperature (T_C) decreases from 302.0 to 270.5 K in the Mn_1.15Fe_0.85P_0.55Si_0.45 alloys and the magnetic-entropy change (ΔS_M) increases linearly with annealing temperature. For the Mn_1.15Fe_0.85P_0.52Si_0.45B_0.03 alloys annealed at 1423 K for different times, T_C decreases from 263.8 and 232.8 K with increasing annealing time and ΔS_M reaches a maximum value after annealing for 48 h. The differences in the annealing temperature and time influence the Si content in the Fe₂P-type phase of the alloys and determine T_C, the thermal hysteresis and the magneto-elastic transition.

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Tactile perception is a complex system, which depends on frictional interactions between skin and counter-body. The contact mechanics of tactile friction is governed by many factors such as the state and properties of skin and counter-body. In order to discover the connection between perception and tactile friction on textured stainless steel sheets, both perception experiments (subjective) and tactile friction measurements (objective) were performed in this research. The perception experiments were carried out by using a panel test method to identify the perceived roughness, perceived stickiness and comfort level from the participants. For the friction experiments, tactile friction was measured by a multi-axis force/torque transducer in vivo. The perceived stickiness was illustrated as an effective subjective stimulus, which has a negative correlation to the comfort perception. No significant evidence was revealed to the connection between the perceived roughness and comfort perception, and this relationship may be influenced by the participants’ individual experience, gender and moisture level of skin. Furthermore, the kinetic tactile friction was concluded as an objective stimulus to the comfort perception with a negative correlation.

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This review gives a concise introduction to the state-of-art techniques used for surface texturing, e.g., wet etching, plasma etching, laser surface texturing (LST), 3D printing, etc. In order to fabricate deterministic textures with the desired geometric structures and scales, the innovative texturing technologies are developed and extended. Such texturing technology is an emerging frontier with revolutionary impact in industrial and scientific fields. With the help of the latest fabrication technologies, surface textures are scaling down and more complex deterministic patterns may be fabricated with desired functions, e.g., lotus effect (hydrophobic), gecko feet (adhesive), haptic tactile, etc. The objective of this review is to explore the surface texturing technology and its contributions to the applications.

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