A Unified Weight Initialization Paradigm for Tensorial Convolutional Neural Networks

Tensorial Convolutional Neural Networks (TCNNs) have attracted much research attention for their power in reducing model parameters or enhancing the generalization ability. However, exploration of TCNNs is hindered even from weight initialization methods. To be specific, general initialization methods, such as Xavier or Kaiming initialization, usually fail to generate appropriate weights for TCNNs. Meanwhile, although there are ad-hoc approaches for specific architectures (e.g., Tensor Ring Nets), they are not applicable to TCNNs with other tensor decomposition methods (e.g., CP or Tucker decomposition). To address this problem, we propose a universal weight initialization paradigm, which generalizes Xavier and Kaiming methods and can be widely applicable to arbitrary TCNNs. Specifically, we first present the Reproducing Transformation to convert the backward process in TCNNs to an equivalent convolution process. Then, based on the convolution operators in the forward and backward processes, we build a unified paradigm to control the variance of features and gradients in TCNNs. Thus, we can derive fan-in and fan-out initialization for various TCNNs. We demonstrate that our paradigm can stabilize the training of TCNNs, leading to faster convergence and better results.Comment: Accepted in ICML 202

Ionic Liquid-assisted Synthesis of Polyaniline/Gold Nanocomposite and Its Biocatalytic Application

In this report, a novel chemical synthesis of polyaniline/gold nanocomposite is explored using ionic liquid (IL) 1-Butyl-3-methylimidazolium hexafluorophosphate. The direct chemical synthesis of polyaniline/gold nanocomposite was initiated via the spontaneous oxidation of aniline by AuCl4−in IL. A nearly uniform dispersion of polyaniline/Au particles with a diameter of 450 ± 80 nm was produced by this method, which indicates that this method is more suitable for controlling particle dimensions. It was also found that the electrical conductivity of the polyaniline/gold nanocomposite was more than 100 times higher than that of the pure polyaniline nanoparticles. The polyaniline/gold nanocomposite displays superior function in the biocatalytic activation of microperoxidase-11 because of the high surface area of the assembly and the enhanced charge transport properties of the composite material. We also report the possible application of polyaniline/gold nanocomposite as a H2O2biosensor

Research on coal mine XR intelligent operation and maintenance system for complex collaborative tasks involving multiple humans and multiple robots

With the development of coal mine intelligence and the application of coal mine robots, an efficient collaboration between coal mine operators and coal mine robots plays a crucial role in the execution of complex underground tasks. To optimize the complex operational relationship of multiple coal mine operators and multiple robots, based on the concept of digital twin and extensive experience in the XR field, the research is conducted on the design and key technologies of XR intelligent operation and maintenance system for complex collaborative tasks involving multiple humans and multiple robots in coal mines. Firstly, for a typical scenario of collaboration between two types of coal mine operators (i.e central control operators and field control operators) and two types of coal mine robots (i.e. detection robots and operating robots) in complex tasks, the overall system architecture is designed. The system is divided into three parts: the physical subsystem, VR operation and maintenance subsystem, and AR operation and maintenance subsystem. The content, functions, and collaborative operation relationships among these three parts are introduced. Then, an analysis of key technologies related to the VR operation and maintenance subsystem, AR operation and maintenance subsystem, and communication networking is carried out. The solutions corresponding to each key technology are discussed, and the integration and operation of the two types of coal mine operators, two types of coal mine robots, and VR/AR operation and maintenance subsystem are implemented. Finally, a laboratory environment simulating complex underground conditions is set up to create a test site, where the task points and specific tasks are defined. The feasibility and effectiveness of the system are tested and verified. The experimental results show that the coal mine XR intelligent operation and maintenance system is able to function in collaborative situations between multiple humans and multiple robots corresponding to different complex tasks. Through the collaborative operation of the VR operation and maintenance subsystem and the AR operation and maintenance subsystem, the collaborative perception, decision-making, and control between virtual space and physical space can be achieved. This allows for the iterative optimization and verification of complex tasks in a physical space from a virtual space, forming an intelligent operational mode of human-human, human-robot, and robot-robot interactive collaboration

A hydrostatic pressure-driven passive micropump enhanced with siphon-based autofill function.

Autonomous and self-powered micropumps are in critical demand for versatile cell- and tissue-based applications as well as for low-cost point-of-care testing (POCT) in microfluidics fields. The hydrostatic pressure-driven passive micropumps are simple and widely used, but they cannot maintain steady and continuous flow for long periods of time. Here, we propose a hydrostatic pressure-driven passive micropump enhanced with siphon-based autofill function, which can realize the autonomous and continuous perfusion with well-controlled steady flow over an extended time without electric power consumption. The characterization results reveal that both the cycle number in one refilling loop and the siphon diameter will affect the refilling time. Furthermore, this micropump also enables multiplexed medium delivery under either the same or different flow conditions with high flexibility. The system was validated using an in vitro vasculogenesis model over the course of several days. Most importantly, the device can consistently provide steady medium perfusion for up to 5 days at a predefined hydrostatic pressure drop without the need for supplemental medium changes. We believe that this hydrostatic pressure-driven passive micropump will become a critical module for a broad range of sophisticated microfluidic operations and applications

Efficient Er/O‐Doped Silicon Light‐Emitting Diodes at Communication Wavelength by Deep Cooling

A silicon light source at the communication wavelength is the bottleneck for developing monolithically integrated silicon photonics. Doping silicon with erbium and oxygen ions is considered one of the most promising approaches to produce silicon light sources. However, this method suffers from a high concentration of defects in the form of nonradiative recombination centers at the interface between the crystalline silicon and large Er2O3/ErSi1.7 precipitates during the standard rapid thermal treatment. Here, a deep cooling process is applied to suppress the growth of these precipitates by flushing the high‐temperature Er/O‐doped silicon substrates with helium gas cooled in liquid nitrogen. The resultant light‐emitting efficiency at room temperature is enhanced by two orders of magnitude in comparison with that of the sample treated via standard rapid thermal annealing. The deep‐cooling‐processed Si samples are further processed into light‐emitting diodes. Bright electroluminescence with a main spectral peak at 1536 nm is also observed from the silicon‐based diodes with the external quantum efficiency reaching ≈0.8% at room temperature. Based on these results, the development of electrically driven silicon optical amplifiers or even lasers at communication wavelengths is promising for monolithically integrated silicon photonics.A deep cooling technique is developed for silicon light sources by suppressing the growth of Er/O‐related precipitates. The resultant near‐infrared emission shows efficiency enhancement by two orders of magnitude. Bright electroluminescence with a main spectral peak at 1536 nm is also observed. The external quantum efficiency can reach 0.8% at room temperature.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/162702/3/adom202000720.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/162702/2/adom202000720-sup-0001-SuppMat.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/162702/1/adom202000720_am.pd

Le regole del gioco: Primo incontro con l'ingegneria strategica

Cu particles decorated carbon composite microspheres (CCMs) with a unique sesame ball structure have been prepared by combining the mass-producible spray drying technique with calcinations. The conventional cuprammonium cellulose complex solution obtained by dissolving cellulose in a cuprammonia solution has been applied as raw materials for the preparation of Cu­(NH₃)₄²⁺/cellulose complex microspheres via a spray drying process. The resulted Cu­(NH₃)₄²⁺/cellulose complex microspheres are then transformed into the Cu particles homogeneously decorated porous carbon spheres <i>in situ</i> by calcinations at 450 or 550 °C. The coordination effect between the Cu­(NH₃)₄²⁺ species and the hydroxyl groups of the cellulose macromolecules has been exploited for directing the dispersion of the Cu particles in the resultant composite CCMs. The antimicrobial effects of the CCMs are evaluated by determining the minimum growth inhibitory concentrations using Staphylococcus aureus and Escherichia coli as representatives, respectively. The CCMs show high efficiency catalytic properties to the conversion of 4-nitrophenol to 4-aminophenol using NaBH₄ as a reductant in a mild condition. The recyclability and stability of the CCM catalysts have also been studied