Prussian
white (PW), due to its low cost, easy synthesis, open
structure, and fast ion extraction/interaction, is introduced to the
electrochromic field. The PW films were successfully grown on indium
tin oxide (ITO) glass by a facial hydrothermal method. Impressively,
the PW film exhibits excellent electrochemical cycling stability without
obvious decay over 10 000 cycles and a high coloration efficiency
of 149.3 cm2 C–1. The film also provides
the large optical transmittance contrast (over 70%) in a wide wavelength
range of 650–800 nm. Furthermore, the PW film shows the rapid
coloration and bleaching response. These results suggest that PW is
a promising practical candidate of high-performance electrochromic
material.
As a kind of novel compliant actuators, pneumatic muscle actuators (PMAs) have been recently used in wearable devices for rehabilitation, industrial manufacturing and other fields due to their excellent actuation characteristics such as high power/weight ratio, safety and inherent compliance. However, the strong nonlinearity and asymmetrical hysteresis cause difficulties in implementing accurate trajectory control for robots actuated by PMAs. In this paper, a method for hysteresis modeling of PMA based on Hammerstein model is proposed, which introduces the BP neural network into the hysteretic system. In order to overcome the limitation of BP neural network's single-valued mapping, an extended space input method is adapted while the Modified Prandtl-Ishlinskii model is applied to characterize the hysteretic phenomenon. A conventional PID control is implemented to track the trajectory of PMA with and without the feed-forward hysteresis compensation based on Hammerstein model, and experimental results validate the effectiveness of the designed model which has the advantages of high precision and easy identification.
Based on backstepping technique, an adaptive inverse control scheme is proposed for a class of uncertain nonlinear systems preceded by unknown hysteretic nonlinearities which are described by Krasnosel'skii-Pokrovkii (KP) model. The pseudo-inversion is introduced to compensate the hysteresis nonlinearities and the error caused by the hysteresis model and pseudo-inversion is estimated online by the adaptive controller. To avoid the possible chattering caused by the sign function, a smooth adaptive controller is designed. The proposed controller ensures the uniformly ultimate boundedness of the closed-loop system. Simulation results show the effectiveness of the proposed scheme.
HF communication is a very important tactical communication method, which can achieve thousand-miles away communication through the ionosphere reflections without any infrastructure support. But HF communication quality is not stable for the ionosphere disturbance, multipath fading and propagation loss. In this paper, we propose a new long-range communication scheme based on majority combing. In the scheme, we use multi-point receiving and multi-copying transmission, which can significantly improve the communication success rate by utilizing the land-sites’ space diversity and the multi-packet’s time diversity.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.