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Industrial textile materials are a new type of functional or structural basic materials processed by weaving, knitting, or nonweaving of fibrous materials. They have been widely applied to aerospace, national defense, ocean engineering, energy, environmental protection, transportation, civil construction, and other fields. The vigorous development of industrial textile materials can significantly promote the manufacturing industry of China, transform and upgrade China’s textile industry into an emerging resource industry, and contribute to the international and domestic dual circulation of China’s textile industry. In this paper, the development status, application scenarios, industrial demand, and manufacturing technologies of industrial textile materials are analyzed, the development direction and focus of relevant technologies and equipment are clarified, and development countermeasures are proposed. Specifically, China needs to formulate special policies to coordinate the technological research, equipment development, production, and application of the industry, establish a standards system for industrial textile equipment, and build systems for innovative services and talent training.

[Introduction] In order to improve the consumption level of renewable energy and measure the risks caused by the uncertainty of its output, this paper used the complementary and coordinated dispatch of different characteristics power as a means to improve the economy of system operation and promote the consumption of renewable energy. Aiming at fluctuation and uncertainty of renewable energy and load, the theory of conditional value-at-risk (CVaR) was introduced to evaluate risks caused by the uncertainty in system dispatching and operation. [Method] Using multi-scenario technology to simulate system uncertainty, a unit commitment and multi-scenario analysis reserve decision optimal dispatching model considering conditional value-at-risk (CVaR) was established, and the objective was to limit the risk level to an acceptable premise and minimize the system operation cost. Finally, the proposed model and method was implemented on GAMS (general algebraic modeling system) platform and solved with the mixed-integer linear programming CPLEX solver. [Result] Simulation calculations show that unit commitment and reserve decision of different types power can effectively improve system operation economy, reliability, and the consumption level of renewable energy. [Conclusion] The rationality and effectiveness of the presented model and method were validated by the numerical results of the improved IEEE 24 and the actual power grid system of a province.

[Introduction] As the guarantee for the stable of the power system, the marketization of the regulation auxiliary service has been put on the agenda. The energy-regulation joint optimization becomes a mode of market organization. This paper aims to study the combined optimization model of the electric energy-regulation market considering the performance difference of frequency modulation resources in the PJM market background. [Method] Regulation auxiliary service pricing adjustment model and the joint clearing model of electric energy and regulation market considering the difference of fast and slow regulation resources and regulation performance was proposed in this paper, which were applied to the simulation of a real power grid to compared with domestic electric energy - regulation step clearing market. Two typical scenarios were set up in wet season and dry season. The clearing of regulation resources, the influence on the electricity purchase cost in the spot market and the active degree of regulation market were studied in detail. [Result] In the stepwise clearing mode, the rapid regulation resource has obvious advantages and causes the increase of electricity purchase cost in the electricity market. In the electricity-regulation joint optimization model, the clearing results of fast and slow regulation resources are affected by the pricing adjustment strategy and the increase rate of electricity purchase costs in the power market is smaller than that in the stepwise model, and the clearing price and fluctuation degree in the regulation market are higher than that in the stepwise clearing mode model. [Conclusion] The combined optimization mode of electric-regulation modulation with reasonable price adjustment strategy is helpful to realize reasonable competition among units with different regulation performance and stimulate market vitality.

Yarn tension during ring spinning is influenced by the shape of the balloon. With the high speed of ring spinning, the existing balloon control technology will have problems with yarn breakage caused by increased tension and yarn wear during the spinning process. Therefore, this article takes the naturally formed multi-balloon as the research object and analyzes the force of the yarn in the balloon section to establish the mathematical model of the steady-state balloon section. Then we selected the appropriate parameters to compare the balloon trajectory graph obtained by simulation and experiment, to verify the validity of the mathematical model. Finally, the relationship between the yarn tension and the number of balloon segments under different balloon heights and spindle speeds, and the conditions for the stable shape of multi-balloon are discussed. It was found that under different balloon shapes, increasing the number of balloon segments can effectively reduce the yarn tension at the yarn guide, and the stable conditions of balloons with different numbers of segments under certain process conditions. The findings are of great significance to the subsequent research on the technological parameters of low-tension spinning and the structural design of ring-spinning machines. [ABSTRACT FROM AUTHOR]

Rich nontrivial topological phases rooted in the interplay between magnetism and topology in the layered antiferromagnet EuCd2As2 have captured vast attention, especially the ideal Weyl semimetal state realized in the spin‐polarized ferromagnetic (FM) structure driven by a moderate external magnetic field. In this work, combining magnetization, magneto‐transport, and structure measurements under high pressure and first principles calculations, this study finds that the pressure can drive the in‐plane antiferromagnetic structure of EuCd2As2 across an intermediate in‐plane FM structure then into the out‐of‐plane FM structure. This study also finds butterfly‐shaped MR and anomalous Hall effect under large pressure, which may support the pressure‐driven FM state. High‐pressure angle‐dispersive X‐ray diffraction and X‐ray absorption near‐edge spectroscopy measurements exclude structure transition and/or change of Eu2+ valence state as sources for the magnetic phase transitions. Alternatively, apparently reduced axial ratio (c/a) and compressed Eu‐layer space distance should play important roles. Interestingly, the calculations unveil that the out‐of‐plane FM structure hosts only one pair of Weyl nodes around the Fermi level, suggesting that pressure can be an alternative way to realize the ideal Weyl semimetal state in EuCd2As2 and will be useful for exploring exotic topological properties in such layered magnetic topological phase with strongly competing magnetic exchanges. [ABSTRACT FROM AUTHOR]

A filament bundle is a type of yarn, which is composed of nearly parallel and highly oriented polymer monofilaments. Due to its nonlinearity both in material constitutive properties and structure, the filament bundle possesses nonlinear viscoelastic properties. It is important to study the dynamic behavior of the filament bundle accurately during its high-speed movement. Therefore, an accurate expression of the constitutive relation of the filament bundle is an essential prerequisite for its dynamic simulation and analysis. Continued the previous study in Part I: modeling filament bundle method, in this paper, an approach was proposed to identify the equivalent dynamic constitutive parameters of the filament bundle considering frequency-dependent characteristics. Firstly, the identification formulas of the dynamic elastic modulus and viscoelastic coefficients were derived based on the Kelvin model. Then, a testing method of the cross-sectional parameters of the filament bundle under a certain tension was proposed, and the testing device was developed to obtain the area of the filament bundle; The dynamic loading test of the bundle filament was conducted in a DMA Q800 dynamic mechanical tester. Thirdly, the equivalent dynamic elastic modulus and viscoelastic coefficients were obtained through the experimental test. Finally, an analytical method was proposed to verify the correctness of experimental results through simulation. The results show that the excitation frequency has a significant influence on the dynamic elastic modulus and viscoelastic coefficient, and the curves of the equivalent dynamic elastic modulus and viscoelastic coefficient present nonlinear variation characteristics. [ABSTRACT FROM AUTHOR]