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With the superior development of technology, mobile robots have become an essential part of humans' daily life. Consequently, interacting and dealing with them pushes us to develop and propose different suitable Human-Robot Interaction (HRI) systems that can detect the interacted user's actions and achieve the desired output in real-time. In this paper, we propose a closed-loop smart mechanism for two main agents: the hand gloves' controller and the mobile robot. To be more specific, the developed model employs flex sensors to measure the curve of the finger. The sensor signals are then processed by aiding the Hedge Algebras Algorithm to control the movement direction and customize the speed of the mobile robot via wireless communication. Numerical simulation and experiments demonstrate that the mobile robot could operate reliably, respond rapidly to control signals, and vary its speed continually based on the different finger gestures. Besides, the control results are also compared with those obtained from the traditional fuzzy controller to prove the superiority and efficiency of the proposed method. [ABSTRACT FROM AUTHOR]

This article proposes a method for optimizing multiple tuned mass damper (TMD) devices for reducing bridge vibration as a vehicle passes over it. The method can design multiple TMD parameters simultaneously for different modes contributing to multiple resonance peaks. Moreover, the study analyzed the vibration of bridges with uncertain parameters. This study's motivation is based on the optimal design of TMDs for bridge structures under external forces, such as the loads of moving cars and high-speed trains. In this case, the resonant response phenomenon can only happen at specific frequencies. The proposed optimization was developed based on the H2 norm method to design the TMD parameters. The target of the present method is to minimize the response peaks around the resonance frequencies. Moreover, the contribution of the excited modes to each other at their resonance frequencies is considered. The TMD parameters were found to demonstrate good performance for reducing the vibration of bridges due to moving vehicles. [ABSTRACT FROM AUTHOR]

Mode-I stress intensity factors are estimated for 28 buckled two-dimensional hexagonal materials, including 6 mono-elemental (silicene, indiene, blue phosphorene, arsenene, antimonene and bismuthene) and 22 binary (CS, CSe, CTe, SiO, SiS, SiSe, SiTe, SiGe, GeO, GeS, GeSe, GeTe, SnO, SnS, SnSe, SnTe, SnGe, SnSi, InAs, InSb, GaAs and AlSb) two-dimensional materials. The crack-tip displacement field revealed from linear elastic fracture mechanics is adopted to find the stress intensity factor. Atomic-scale finite element method with Stillinger-Weber potentials is used to simulate the tensile tests. Mode-I stress intensity factors of these 28 two-dimensional materials appear ≤ 0.8 MPa m , which are very small in comparison with boronitrene and graphene. Most of them exhibit their fracture toughness below 0.5 MPa m. Our findings are helpful in the design of nano-devices with these two-dimensional materials. [ABSTRACT FROM AUTHOR]

Despite the enormous attention paid to cobalt oxide materials as efficient water splitting electrocatalysts, a deep understanding of their activity discrepancy is still elusive. In this work, we showed that stabilization of the internally generated oxygen evolution reaction (OER) active phase (oxyhydroxide) is crucial for ZnCo 2 O 4 electrocatalysts. A systematic evaluation of the bulk and nanostructured ZnCo 2 O 4 system concomitant with nanostructured Co 3 O 4 showed that leaching of Zn is the driving force behind the near-surface transformation to the oxyhydroxide phase. The relative contribution to this near-surface reconstruction was found to be surface-sensitive. The electrochemical observations combined with Raman and impedance spectroscopy revealed that the good catalytic activity could be attributed to the formation of the cobalt oxyhydroxide phase, which was created by the dissolution of Zn from the nanostructured surface. Moreover, this study sheds light on previous contradicting postulates regarding the discrepancy of the OER activity of ZnCo 2 O 4 . Our finding regarding the formation of the OER active phase in spinel Zn-Co oxide will motivate researchers to focus more on the near-surface reconstruction behavior of cobalt-based oxide electrocatalysts in the future.