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Navigation applications relying on the Global Navigation Satellite System (GNSS) are limited in indoor environments and GNSS-denied outdoor terrains such as dense urban or forests. In this paper, we present a novel accurate, robust and low-cost GNSS-independent navigation system, which is composed of a monocular camera and Ultra-wideband (UWB) transceivers. Visual techniques have gained excellent results when computing the incremental motion of the sensor, and UWB methods have proved to provide promising localization accuracy due to the high time resolution of the UWB ranging signals. However, the monocular visual techniques with scale ambiguity are not suitable for applications requiring metric results, and UWB methods assume that the positions of the UWB transceiver anchor are pre-calibrated and known, thus precluding their application in unknown and challenging environments. To this end, we advocate leveraging the monocular camera and UWB to create a map of visual features and UWB anchors. We propose a visual-UWB Simultaneous Localization and Mapping (SLAM) algorithm which tightly combines visual and UWB measurements to form a joint non-linear optimization problem on Lie-Manifold. The 6 Degrees of Freedom (DoF) state of the vehicles and the map are estimated by minimizing the UWB ranging errors and landmark reprojection errors. Our navigation system starts with an exploratory task which performs the real-time visual-UWB SLAM to obtain the global map, then the navigation task by reusing this global map. The tasks can be performed by different vehicles in terms of equipped sensors and payload capability in a heterogeneous team. We validate our system on the public datasets, achieving typical centimeter accuracy and 0.1% scale error.

electric or solar energy as a driving force is a promising measure to realize the generation of green energy source. [1,2] However, electro-and photocatalytic hydrogen evolution reaction (HER) both confront a big challenge regarding the conversion efficiency and economical cost. [3][4][5][6] There are two general concerns for the two mentioned HER pathway, that is the low charge transport efficiency and surface reactivity. [7][8][9] Therefore, material design to overcome the general shortcomings for HER is urgent to boost the performance.Structural engineering of nanomaterials has been proven as a powerful pathway to tune their physico-chemical and electronic properties, and thus resulting in improved catalytic performance. [10][11][12] Transitional metal dichalcogenides (TMDs) represented by MoS 2 are advancing catalysts for HER, owing to the hydrogen adsorption ability and earth-abundant characteristics. [13][14][15] Recent reported structural engineering strategies for TMDs generally focus

All-inorganic perovskite has been generally used in memristor due to its outstanding characteristics such as superior optical performance, superior stability, tunable and highly effective photoluminescence. We have proved the use of all-inorganic halide perovskite as a medium in memristor. In this paper, the memristor with construction of Au/CsPbBr3/FTO, Au/CsPbBr3/ZnO/FTO and Au/ZnO/CsPbBr3/FTO were manufactured by one-step spin-coating approach to observe representative bipolar resistance switching behaviors in different construction of resistance random access memory devices. Results show that the memristor based on ZnO/CsPbBr3 heterojunction having excellent resistance switching effect with low resetting, setting voltages and and high environmental stability. Moreover, a model of filaments through the CsPbBr3 layer was raised to interpret the resistive switching effect.

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