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For civil aircraft, the reliability of control device sensors in flight control system is very important for aircraft control and safe flight. Redundancy signal voting and monitoring technology can improve the availability and integrity of sensor signals in fly by wire primary flight control system of civil aircraft. In this paper, a simplified four-redundant signal voting and monitoring method is proposed which randomly and dynamically divides the four redundant signals into two groups for comparison. The safety analysis and simulation results reveal that this simplified method meets the safety requirements and has advantages in robustness and availability.

The static recrystallization (SRX) behavior of an ultrahigh-strength stainless steel (UHSSS) was investigated via double-hit isothermal compression tests. The results revealed that the kinetics of static recrystallization and the corresponding microstructural evolution were not only prominently influenced by the deformation parameters and initial microstructures but also suppressed due to the precipitation of M6C carbides below 1050 °C, which sufficiently pinned the boundaries. Numerical models for predicting the recrystallized fraction and grain sizes were proposed based on the experimental results. The kinetics model could predict the process of SRX in the deformation temperature range from 1050 °C to 1150 °C well, whereas there were some deviations between the predictions and experimental results due to the interaction of the M6C carbides and SRX when the deformation temperature was below 1050 °C.

In order to study the corrosion resistance of the stainless steel bars under marine environmental attack, simulated seawater drying and wetting test on the two types of the stainless steel bars (SSRs), 304 and 316L austenitic SSRs as well as S32304 and S32205 duplex SSRs, was carried out in the laboratory. Electrochemical monitoring of open-circuit potential, linear polarization and electrochemical impedance spectroscopy (EIS) was carried out via CS310H electrochemical potentiostat. Zview software was used to discuss the measured data. Results show that the Stern-Genry coefficient B of the ordinary carbon steel bar is about 20mV, while those values of the duplex SSRs and austenitic SSRs are in the range of 14∼16mV and 15∼17mV, respectively. For the above-listed reinforcement, better corrosion resistance is shown in the duplex SSRs with the best behaviour observed in S32304 duplex SSRs; the corrosion resistance of the austenitic SSRs 304 and 316L is good and similar, while poor corrosion resistance is shown in the ordinary carbon steel bar as expected.

Under the marine environment, the durability of the reinforced concrete (RC) infrastructures is greatly influenced by the chloride-induced corrosion of the ordinary reinforcing bars. In order to prolong the service life of the RC infrastructures, stainless steel rebars (SSRs) are gradually used in marine infrastructures due to their better corrosion resistance. However, research on the corrosion and mechanical properties of the SSR under marine environmental attack is quite limited. In this paper, tensile tests at room temperature were carried out on corroded SSR samples with different types and diameters. Results show that, no obvious yielding plateaus can be observed in the stress-strain relation curves of the SSRs when compared with those of the ordinary carbon steel bars; the yielding strength and ultimate strength of the corroded ordinary carbon steel bars and SSRs decrease with the increased average cross-sectional loss while the elongation change of the corroded SSRs with the average cross-sectional loss is variable. Basing on the constitutive model of uncorroded SSR proposed by Ramberg and Osgood and considering the influence of the average and maximum cross-sectional loss on the strengths of corroded SSRs, stress-strain constitutive models of the corroded SSRs were proposed.

In this study, fluorescence-encoded magnetic biocompatible nanoparticles (NPs) were constructed from CdSe@ZnS quantum dots (QDs) and Fe3O4 nanoparticles with a one-step reprecipitation-encapsulation method. The resultant hybrid NPs exhibit small size (∼130 nm in diameter), highly bright QDs, two-color emissions (green and red) under single-wavelength excitation, easy separation with a magnet and efficient cellular internalization. Energy transfer between the incorporated QDs was studied to better tailor the encoded fluorescence, and 11 barcodes were obtained by adjusting the ratio of green and red QDs. We used four sets of the barcodes to tag specific cancer cells (HepG2) as a proof-of-concept, and distinguished each set according to respective overlayed fluorescence images using laser confocal microscopy. Moreover, the incorporated Fe3O4 NPs endowed as-constructed optical barcode superparamagnetic property by T 2-enhanced magnetic resonance effect with an r 2 value of 145.25 s-1 mM-1 at 3 T. These results suggest that the multifunctional NPs are very promising for discriminating different cells and dual-modality imaging.

To increase the quantum efficiency (QE) of a copper photocathode and reduce the thermal emittance of an electron beam, a drive laser with oblique incidence was adopted in a BNL type photocathode rf gun. The disadvantageous effects on the beam quality caused by oblique incidence were analyzed qualitatively. A simple way to solve the problems through wavefront shaping was introduced and the beam quality was improved.

In this paper we interpret the hidden symmetry of the moduli space of IIB superstring on $AdS_{5}\times S^{5}$ in terms of the chiral embedding in $AdS_{5}$, which turns to be the $\mathbb{CP}^{3}$ conformal affine Toda model. We review how the position $\mu $ of poles in the Riemann-Hilbert formulation of dressing transformation and how the value of loop parameters $\mu $ in the vertex operator of affine algebra determines the moduli space of the soliton solutions, which describes the moduli space of the Green-Schwarz superstring. We show also how this affine SU(4) symmetry affinize the conformal symmetry in the twistor space, and how a soliton string corresponds to a Robinson congruence with twist and dilation spin coefficients $\mu $ of twistor.

Ceramic coatings were fabricated on the surface of LY12 aluminum alloy by micro-arc oxidation (MAO) method in NaSiO3-NaOH solution. Effect of experimental parameter on the MAO film was investigated. The results show that the ceramic layers formed on the surface of the alloy show different surface morphologies, and thickness of MAO film increases with the increase of voltage and oxidation time. These films contain two layers, an outer porous layer and an inner barrier layer, which consists mainly of γ-Al2O3 phase and a small amount of α-Al2O3 phase..