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Describes a new catalytic gas sensor which claims high stability and low‐consumed power by using extra fine wires of precious metals and the addition of a support stabilizer and pore‐making agents. Outlines the experiment methods and materials used, the principles of detection and the performance of the catalytic elements. Concludes that with the addition of a support stabilizer which makes the specific surface of the support decrease slowly during use, and a pore‐making agent which can eliminate the effect of the internal diffusion on the sensor, the novel catalytic sensor can be widely applied to the detection of damp gas in coal mines and various combustible gases on the earth’s surfaces.

Improvement and optimization design of a two-stage vibration isolation system proposed in this paper are conducted to ensure the device of electronic work effective.

The proposed two-stage vibration isolation system of airborne equipment is optimized and parameterized based on multi-objective genetic algorithm.

The results show that compared with initial two-stage vibration isolation system, the angular vibration of the two-stage vibration isolation system becomes 3.55 × 10^-4 rad, which decreases by 89%. The linear isolation effect is improved by at least 67.7%.

The optimized two-stage vibration isolation system effectively improves the vibration reduction effect, the resonance peak is obviously improved and the reliability of the mounting bracket and the shock absorber is highly improved, which provides an analysis method for two-stage airborne equipment isolation design under complex dynamic environment.

This paper aims to propose a new concept of product manufacturing mode which takes physical manufacturing theory as the basic starting point. In this work, the authors intend to systematically define the basic connotation and extension of physical manufacturing, and sort out the typical characteristics of physical manufacturing, in order to propose the general concept of physical manufacturing.

How to study the combination of physics, mathematics, mechanics and other disciplines with the manufacturing disciplines, and how to elevate modern manufacturing science to a new height, has always been a problem for scientists in the field of manufacturing and engineering construction people to deeply think about. Therefore, on the basis of tracing the development of physics and combining the attributes and functions of manufacturing, the authors propose the basic concept of physical manufacturing. On this basis, the authors further clarify the connotation and extension, theoretical basis and technical system of physical manufacturing, reveal the basic problem domain of research and construct the theoretical foundation of physical manufacturing research, which are of great theoretical value and practical significance to adjust and optimize the manufacturing industry structure, improve the quality of manufacturing industry development and promote the green development of manufacturing industry.

The research on the basic theory and technical system of physical manufacturing will therefore broaden the way of thinking and make a better understanding of manufacturing science and technology, which will promote the development of manufacturing industry to some extent.

On the basis of continuous improvement of the basic theory and conceptual system of physical manufacturing, the physical manufacturing technology will become more and more perfect; physical manufacturing system and intelligent manufacturing system will become the mainstream of next-generation manufacturing system.

When dealing with simple functional functions, traditional reliability calculation methods, such as the linear second-order moment and quadratic second ordered moment, Monte Carlo simulation method, are powerful. However, when the functional function of the structure shows strong nonlinearity or even implicit, traditional methods often fail to meet the actual needs of engineering in terms of calculation accuracy or efficiency.

To improve the reliability analysis efficiency and calculation accuracy of complex structures, the reliability analysis methods based on parametric and semi-parametric models are analyzed.

This paper proposes a reliability method that combines the Kriging model and the importance sampling method to improve the calculation efficiency of traditional reliability analysis methods.

This method uses an active learning function and introduces an importance sampling method to screen sample points and shift the center of gravity, thereby reducing the sample size and the amount of calculation.