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Flexible chemical sensor with high sensitivity and reliability is important for health monitoring applications. A typical sodium-ion detection sensor based on ion selection is made of a reference electrode and a working electrode. The reliability of the electrodes is still challenging to achieve accurate and continuous measurements. Here we use the polydopamine-printed technology and chemical annealing method to prepare the flexible sodium-ion detection sensor that presents enhanced reliability. A sensitivity of 54 mV per decade is achieved for the sensor. In the best case, the reliabilities of the working and the reference electrodes are increased up to 95.3% and 93.9%, respectively for the detection of the sodium-ion concentration. This work provides a method to improve the stability of the flexible ion detection sensors.

Graphene is a typical two-dimensional material which has fascinating electrical, mechanical, and optical properties. In particular, graphene-based smart MEMS/NEMS devices can automatically respond to external electric stimulation and convert to mechanical movement. Actuator is one of the most potential applications of graphene-based MEMS. However, its reliability investigation has rarely been reported. Here we report the failure mechanism of a bimorph actuator fabricated by reduced graphene (RGO) and graphene oxide (GO). Our findings pave a way to the fundamental understanding of reliability issues on graphene-based actuators.

In this paper, a grid-base autonomous geographic routing is proposed to decrease end-to-end delay and improve network capability for wireless sensor networks. After numbering grids in sequence, every grid has a unique ID. In this case, any node can utilize local decision to figure out which neighboring grid is closest to the center nodes. Since it is not needed to establish a routing in advance, this algorithm is very suitable for dynamic networks, real-time traffics and burst communications. By Matlab and Ns-2 simulation, the novel routing algorithm exhibits excellent performance in packet delivery fraction, end-to-end delay, protocol overhead, and path length.

In the radio channel, compression is used for transmission of real-time analog video signal and compressed bits can usually be transmitted at a non-constant rate. But standard video can be displayed on TV at a constant rate. It is difficult to decode the intermittent compressed data for real-time video display. In order to solve the problem which rate of video decoding and compressed bits in the radio channel does not match, a method is brought forward. By controlling the data which transmit to the decoder, the real-time sequential video can be displayed. And the method has been used to the system of video transmission. Its reliability and validity can be proved.

To sovle high torque ripple at low speed, high frequence noise and slow response caused by torque ripple for conventional control systems of permanent magnet synchronous motor(PMSM), the scheme of Digonal Recurrent Neural Network(DRNN) Dynamic speed Controller for space vector PWM(SVPWM) control of a permanent magnet synchronous motor(PMSM) is presented. The structure of dynamic PID speed Controller based on digonal recurrent neural network(DRNN-PID), and an dynamic learning algorithm are analyzed. The results of simulation are provided to demonstrate system superior characteristics with low torque ripple, few harmonics and the effectiveness of the proposed DRNN dynamic speed Controller under the occurrence of parameter variations and external disturbance.

As one important technoly in converter steelmaking, oxygen lance position control is investigated with self-adaptive fuzzy PID strategy. We employ the fuzzy reasoning to realize the real-time adjustment of the parameter of PID in order to control the oxygen lance position. With the details of the fuzzy controller, the practical oxygen lance is simulated by using Matlab. The results imply that the self-adaptive fuzzy PID has better properties in obtaining dynamical index and steady state than the regular PID control strategy.