QoTa-MPR: QoS-oriented and traffic-aware multi-path routing protocol for internet of remote things

Telecommunication Systems - Internet of Remote Things (IoRT) is widely used in both military and civilian applications. However, due to the unique characteristics, which is characterized as...     

Regulation and Reconstruction of Cell Phenotype Gradients Along the Tendon-Bone Interface

Tendon–bone interface is prevalent in the human body. It is divided into four zones: tendon (soft tissue), unmineralized fibrocartilage, mineralized fibrocartilage, and bone (hard tissue). Tendon–bone interface is characterized by a cell phenotype gradient that appears in the different zones. The cell phenotype gradients at the tendon–bone interface are orchestrated by specific intracellular molecular mechanisms, extracellular factors, immune signals, and neurovascular factors. These features have inspired scientists to design systems that mimic natural cell phenotype gradients. These biomimetic systems include the construction of cell sheets, regulation of cellular microenvironments, and the design of gradient functional scaffolds. Exploration of methods to mimic cell phenotype gradients is instructional for future clinical applications in reconstituting the tendon–bone interface. The present review elucidates the gradient composition of the tendon–bone interface. The associated regulatory mechanisms and applications are discussed, with the anticipation of creating a mise en scène for future research in interface tissue engineering.     

一种基于最优组合模型的火箭弹跟踪算法

提出一种基于最优组合模型对火箭弹运行参数进行预测,利用它对跟踪的特征点下一位置进行预测。该模型的主要特点是避免了单一预测模型仅利用部分信息而带来的不足,详细推导了算法的数学模型。仿真结果证实了该模型较单一预测方法降低了预测误差、提高了预测精度,使得跟踪算法的精度得到很大提高。     

Wideband direction-of-arrival estimation using frequency-domain frequency-invariant beamformers: an analysis of performance

This paper presents an extension of the wideband direction-of-arrival estimation method using frequency-domain frequency-invariant beamformers (Do-Hong et al., 2003) with an analysis of performance. An asymptotic expression for the root-mean-square error and a resolution threshold of signal-to-noise-ratio for resolving directions of sources are shown. A comparison of analysis and simulation as well as numerical results are also presented.     

Plasmonic Dual‐Enhancement and Precise Color Tuning of Gold Nanorod@SiO2 Coupled Core–Shell–Shell Upconversion Nanocrystals

The last decade has witnessed the remarkable research progress of lanthanide‐doped upconversion nanocrystals (UCNCs) at the forefront of promising applications. However, the future development and application of UCNCs are constrained greatly by their underlying shortcomings such as significant nonradiative processes, low quantum efficiency, and single emission colors. Here a hybrid plasmonic upconversion nanostructure consisting of a GNR@SiO₂ coupled with NaGdF₄:Yb³⁺,Nd³⁺@NaGdF₄:Yb³⁺,Er³⁺@NaGdF₄ core–shell–shell UCNCs is rationally designed and fabricated, which exhibits strongly enhanced UC fluorescence (up to 20 folds) and flexibly tunable UC colors. The experimental findings show that controlling the SiO₂ spacer thickness enables readily manipulating the intensity ratio of the Er³⁺ red, green, and blue emissions, thereby allowing us to achieve the emission color tuning from pale yellow to green upon excitation at 808 nm. Electrodynamic simulations reveal that the tunable UC colors are due to the interplay of plasmon‐mediated simultaneous excitation and emission enhancements in the Er³⁺ green emission yet only excitation enhancement in the blue and red emissions. The results not only provide an upfront experimental design for constructing hybrid plasmonic UC nanostructures with high efficiency and color tunability, but also deepen the understanding of the interaction mechanism between the Er³⁺ emissions and plasmon resonances in such complex hybrid nanostructure.     

Transparent,Highly Stretchable,Rehealable, Sensing,and Fully Recyclable Ionic Conductors Fabricated by One‐Step Polymerization Based on a Small Biological Molecule

To date, various stretchable conductors have been fabricated, but simultaneous realization of the transparency, high stretchability, electrical conductivity, self‐healing capability, and sensing property through a simple, fast, cost‐efficient approach is still challenging. Here, α‐lipoic acid (LA), a naturally small biological molecule found in humans and animals, is used to fabricate transparent (>85%), electrical conductivity, highly stretchable (strain up to 1100%), and rehealable (mechanical healing efficiency of 86%, electrical healing efficiency of 96%) ionic conductor by solvent‐free one‐step polymerization. Furthermore, the ionic conductors with appealing sensitivity can be served as strain sensors to detect and distinguish various human activities. Notably, this ionic conductor can be fully recycled and reprocessed into new ionic conductors or adhesives by a direct heating process, which offers a promising prospect in great reduction of electronic wastes that have brought acute environmental pollution. In consideration of the extremely facile preparation process, biological available materials, satisfactory functionalities, and full recyclability, the emergence of LA‐based ionic conductors is believed to open up a new avenue for developing sustainable and wearable electronic devices in the future.     

A second-order double-sampled delta-sigma modulator usingindividual-level averaging

A second-order double-sampled delta-sigma modulator is described. It uses all individual-level-averaging switching scheme to convert capacitor mismatch into high-pass noise. With a sampling rate of 25 MHz and an oversampling ratio of 128, the maximum measured signal-to-noise-and-distortion ratio is 82.2 dB, and the total harmonic distortion is -91.0 dB when the input is 2.5 dB below full scale. The modulator is fully differential, occupies 3.75 mm² in a 1.2-μm CMOS process, and dissipates 25.9 mW (10.2 mW analog and 15.7 mW digital)     

C+注入Si形成SiC/Si异质结构的椭偏光谱

用椭偏光谱法测量了(35keV,1.0×10118cm-2)和(65keV,1. 0×1018cm-2)C+注入Si形成的SiC/Si异质结构.应用多层介质膜模型和有效介质近似,分析了这些样品的SiC/Si异质结构的各层厚度及主要成份.研究结果表明:注35keV C+的样品在经1200 C、2h退火后形成的SiC/Si异质结构,其β-SiC埋层上存在一粗糙表面层,粗糙表面层主要由β-SiC、非晶Si和SiO2组成,而且β-SiC埋层与体硅界面不同于粗糙表面层与β-SiC埋层界面;注65keV C+的样品在经1250 C、10h退火后形成的SiC/Si异质结构,其表层Si是较完整的单晶Si,埋层B-SiC分成三层微结构,表层Si与β-SiC埋层界面和β-SiC埋层与体硅界面亦不相同.这些结果与X射线光电子谱(XPS)和横截面透射电子显微镜(TEM)的分析结果一致.