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А method for generating a pseudo-random response in a linear dynamic system is considered. An example of the system transition to pseudochaotic behavior is given. The calculation of fatigue loads in the toggle plate by the given method is presented. The advantage of this method in calculating fatigue loads is shown.

The description of crusher design is given, in which the destruction of the processed material occurs due to the forces acting on the crushed piece in the same plane towards each other, while in the processed piece only tangential stresses arise. It makes possible to reduce the energy consumption per unit of finished product by almost two times.

Cytokine-induced killer (CIK) cells were isolated and proliferation from human peripheral blood and cultured in appropriate growth medium. The biological characteristics of CIK cells were further determined by the characterization of surface markers by flow cytometry. CIK cells inhibited the proliferation of human lung adenocarcinoma NCL-H157 cells. Vascular endothelial growth factor (VEGF) expression was down-regulated in CIK cells co-cultured with NCL-H157 cells by western blotting analysis. Furthermore, in comparison with cells untreated by CIK, the NCL-H157 had a lower proliferation capacity. We proposed that the pharmacological mechanisms of NCL-H157 promoted by CIK can be estimated possibly with different biological significance that can be ascribed to down-regulated VEGF expression in vitro. The results suggest that the VEGF pathway guides developmental inhibiting of NCL-H157, and we speculate that the function of VEGF pathways is to guide NCL-H157 to inhibition by abundant CIK.

In this work, a new welding method, AC-DC hybrid TIG welding, is used to weld 304 stainless steel. Research on the formation, microstructure, and properties of 304 stainless-steel welded joints are studied by using optical microscope and microhardness. The results show that the weld with AC/DC hybrid welding is a fish-scale pattern, and the density of the fish-scale pattern increases with the increase of AC proportion. Both the weld penetration and the ratio of weld penetration to weld width are the highest when AC accounts for 30%. At this point, the weld penetration is 0.83 mm larger than DC mode, an increase of 93.26%, and the ratio of weld penetration to weld width is 1.6, which is 76.19% higher than DC mode. When the proportion of AC is increased, the microstructure of the weld is equiaxed or columnar, and the microstructure of the heat-affected zone is ferrite in the form of lath. The hardness of the weld is greater than that of the base metal, and the hardness of the heat-affected zone is the lowest. The microhardness distribution of the weld with AC 50% is the most uniform. When AC accounts for 20% and 30%, the average weld hardness is the highest, which are 196.7 HV and 198.1 HV, respectively. [ABSTRACT FROM AUTHOR]

The solubility of Na2O·xAl2O3 in a NaF-KF-AlF3-based low-temperature electrolyte was investigated, and the influence of electrolyte temperature at 750 ℃, CR = 1.3–1.4, CaF2, and LiF on the alumina solubility was studied. The dissolution rate of alumina in the electrolyte was determined by measuring the alumina concentration in the electrolyte at different times with an oxygen analyzer. The results showed that in the NaF-KF-AlF3-based low-temperature electrolyte, the dissolution rate of alumina in Na2O·xAl2O3 was faster than that of Al2O3. As the Na2O content in alumina increased, the dissolution rate increased. Similarly, a higher CR of NaF-KF-AlF3 and a higher temperature of the molten salt (750–850 °C) increased the dissolution rate of alumina in the electrolyte. The dissolution rate of alumina in NaF-KF-AlF3 decreased after adding CaF2 and LiF. According to the kinetics analysis, the dissolution rate of alumina followed the zero-order reaction rate law from 0–5 min, which showed that it depended on the amount of alumina absorbed in the electrolyte in the first five minutes. [ABSTRACT FROM AUTHOR]

This article investigates the adaptive finite time tracking control problem for quadrotor unmanned aerial vehicles (QUAV) subject to actuator failure with event‐triggered control strategy. It is assumed that the models of actuator failure are actuator blockage and saturation faults. The finite time performance function and adaptive backstepping method are combined to design the controller to compensate the influence of actuator failure, so as to ensure that the tracking error converges to the preset neighborhood near the origin in finite time. In addition, a new event‐triggered strategy is introduced to save communication resources and avoid the Zeno‐behavior, which defines the variable threshold as a function combining with tracking error and positive constants. The variable threshold not only effectively reduces triggering times, but also makes the design of the controller more flexible. It is proved that the closed‐loop system is stability. Finally, the effectiveness of this method is verified by simulation. [ABSTRACT FROM AUTHOR]