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Prefabricated electrochemical energy storage stations are crucial for the promotion and application of energy storage projects. To conduct research on digital twin technology throughout the lifecycle， the paper proposes a method for establishing a digital twin model for electrochemical energy storage power stations based on electric-thermal-fluid fields. Firstly， standardized testing protocols for batteries are designed to acquire fundamental characteristics such as capacity， energy， open circuit voltage （OCV）， and power， as well as the coupling laws of multiple physical fields of batteries. Subsequently， battery model parameters are identified through test data， and an aging model parameter database is constructed. Next， the aging process of batteries is revealed based on incremental capacity analysis （ICA）， and the maximum available capacity of the batteries is extracted through feature mapping. Following this， leveraging the coupling characteristics of multiple physical fields of batteries， thermal and fluid field models of battery compartments are established using real-world laser scanners， engineering drawings， and COMSOL Multiphysics software. Finally， technical validation is performed using a user-side prefabricated energy storage station in Zhejiang Province， demonstrating that the established digital twin model enables deduction and state assessment of electric-thermal-fluid fields.

In order to enhance the efficiency of renewable energy utilization and the economic and environmental performance of distributed electric-thermal-hydrogen energy systems， a unified model for multi-type electrolyzers is established considering the strong fluctuation of wind and solar power generation and the differentiated features of multi-type electrolyzers. A method for optimizing the design of electric-thermal-hydrogen energy systems is proposed， taking into account the differentiated characteristics of multi-type electrolyzers. This method comprehensively utilizes alkaline electrolyzers， proton exchange membrane electrolyzers， and solid oxide electrolyzers， considering their differences in terms of economic viability， flexibility， and efficiency. This approach aims for consumption of renewable energy sources with different fluctuation characteristics. Case study results indicate that this method effectively integrates the differentiated features of multi-type electrolyzers， aligning the operational flexibility of various electrolyzers with the fluctuations in wind and solar power outputs. As a result， it comprehensively enhances the economic and environmental performance of electric-thermal-hydrogen energy systems.

As an important part of strategic emerging industries, the new-generation information technology plays a major leading role in the overall and long-term development of the economy and society. The new-generation information technology industry is also the cornerstone for cultivating new quality productivity, and is an important starting point for opening up new fields and tracks for development and for shaping new momentum and advantages. Based on the implications of the new-generation information technology industry, this study sorts out the global development trend of the new-generation information technology industry, summarizes the current status and development trend of the industry in China, and analyzes the opportunities and challenges faced by the industry. Moreover, focusing on the requirements of high-quality development of the new-generation information technology industry, the study proposes the following countermeasures and suggestions: (1) improving the integrated strategic system and capabilities while adhering to a system engineering thinking; (2) strengthening the research of key core technologies to strengthen the basic capacity of the industry; (3) promoting the integrated and clustered development of industries, highlighting enterprises as the main body; (4) constructing an open innovation ecosystem based on scenario-driven innovation; and (5) promoting the coordinated development of production, education, research, application, and funds to cultivate a high-level talent team.

In response to the impact of the widespread integration of new energy sources on the secure operation of distribution networks， a study is undertaken to explore a multi-time scale interactive strategy for distributed electro-hydrogen coupled systems， incorporating hybrid energy storage and distribution networks. Firstly， interactive mechanisms including the balancing service mechanism and demand response mechanism between distributed electro-hydrogen coupled systems and distribution networks are proposed. Secondly， based on game theory， medium-to-long-term and short-term interactive strategies are formulated for electro-hydrogen coupled systems and distribution networks. Finally， a simulation analysis is executed utilizing the distribution networks and distributed electro-hydrogen coupled system in a representative region as an illustrative example. The outcomes of the case study underscore that hydrogen storage exhibits an advantage in medium-to-long-term interactions due to its cross-period characteristics. Electrochemical storage， distinguished by its rapid response， proves more suitable for short-term interactions. In comparison to singular energy storage systems， a hybrid electro-hydrogen storage system can effectively mitigate difference between peak and valley loads， enhancing system benefits， and seamlessly aligning with the existing distribution network system.

Microgrid clusters （MGCs）， comprising distributed clean energy sources， play a pivotal role in fostering source-grid-load-storage interaction and efficient utilization of distributed new energy sources. To give full play to the advantages of mutual power support and cooperative MGC operation， electrical boundaries of microgrids can be dynamically adjusted through contact switches to realize source-load transfer and flexible scheduling of regional resources. Given the transient impact caused by the topology switching of MGC， the seamless transfer strategy of distributed supply and demand power and the method of load transfer selection in emergencies are proposed. By reducing the tie line interaction power through cooperative control of distributed power sources， the inrush current during the switching of the contact line is reduced， and power distribution and voltage deviation restoration within each microgrid are implemented. Compared with the conventional optimization strategies focusing on topology reconfiguration， the fluctuations in topology switching can be mitigated by distributed control， which effectively utilizes the potential of distributed power utilization and improves the power supply reliability of the MGC in case of failure.

An Unscented Kalman Filter with multi model adaptive estimation algorithm (MMAE-UKF) based on dynamic characteristic template is proposed to solve the problem of trajectory estimation of interceptor in boost phase by using passive detection method for single aircraft. Under the condition of incomplete observation information, by introducing the interceptor dynamic characteristic template, the design parameters of flight program model and launch azimuth angle are expanded to target state components. Based on the flight program model and dynamic characteristic template, a nonlinear MMAE model set is constructed. The flight program model and design parameters of the interceptor are identified using the MMAE-UKF algorithm, and the motion state of the interceptor in boost phase is estimated. The simulation results show that the algorithm can quickly and accurately identify the flight program model and design parameters used in the boost phase of the interceptor. Compared with the traditional expanded state filtering algorithm, the motion state estimation error is significantly reduced, and the filtering stability speed is greatly improved.

Aiming at the problem of tracking skip-glide targets using radar, this paper proposes an Unscented Kalman Filter (UKF) tracking algorithm based on the improved Jerk model. Aiming at the estimation error introduced by the artificial preset acceleration variance and Jerk frequency of the conventional Jerk algorithm, this method calculates the acceleration variance adaptively through the current position estimation value and the current position one-step prediction value, and correlates the jerk frequency with the acceleration variance, realizing the adaptive adjustment of the model parameters while estimating the target motion state. At the same time, the improved Jerk model is combined with UKF algorithm, and the overall algorithm flow is given, and simulation experiments are carried out. The simulation results show that compared with the conventional Jerk model algorithm, the method proposed in this paper realizes the adaptive adjustment of model parameters, making the tracking process more adaptable to the maneuvering characteristics of the target.

The hydrogen-electric coupling system is an important and indispensable part of a new-type power system， and its safety is a prerequisite for large-scale application. The hydrogen-electric coupling system is studied， and the accidents in key hydrogen-related equipment are summarized and investigated.Furthermore， fault tree analysis （FTA） is used for safety risk evaluation on the combustion and explosion of the hydrogen-electric coupling system caused by hydrogen leakage. The study shows that hydrogen storage and compression equipment is prone to safety accidents， and design defects， sealing， and operation errors are major causes of hydrogen accidents. The fault tree analysis shows that there are five ways to effectively prevent the hydrogen-electric coupling system from fire or explosion due to hydrogen leakage. The importance of the hazard sources and basic events of the system obtained from the study lays the foundation for developing safety protection measures.

ObjectiveTo systematically investigate the health food containing probiotics approved by the government in China， and analyze the application of strains， function claims， recommended intake and distribution of applicable population， and provide reference for the management reform of probiotics products.MethodsThe information of health food containing probiotics approved by the government in China from 1996 to 2022 were collected and investigated， including the kinds of probiotics， function claims， recommended intake and the information of applicable populations.ResultsA total of 168 health foods containing probiotics were approved in China from 1996 to 2022， 82.14% and 77.98% of the products used Lactobacillus and Bifidobacterium respectively， 61.31% of the products used Lactobacillus acidophilus， but all products were not labeled with the level of strain. In terms of function claims， most products claimed “enhancing immunity”， “regulating intestinal flora” and “laxative”. The recommended intake of probiotics ranged from 0.12 to 3.63×1011 CFU/d. Claims such as “immunocompromised people”， “people with intestinal flora imbalance” and “people with constipation” were the most common applicable populations for consumption. 42.86% of the products did not labeled with “the unsuitable population”， and more than 69.79% of the products labeled with “the unsuitable population” targeted at infants and young children.ConclusionThere are some approved health food containing probiotics in China， none of which is clearly labeled to the strain level， which is not in line with the scientific definition of probiotics. The existing products are of a single function， product function claim depends on the results of high-quality population studies. The approval of products suitable for infants and young children should be scientific and prudent.

With the large-scale access of renewable energy， the configuration of energy storage system （ESS） has become an important means to improve the flexibility and reliability of the grid. Given the problem of low utilization rate of ESS in a single-application scenario， an optimal configuration method of ESS for multi-application scenarios is proposed to improve the utilization rate of ESS and enhance the voltage stability of power grid. Firstly， this paper establishes a mathematical model of ESS under the three application scenarios of smoothing wind and solar output fluctuation， auxiliary frequency regulation and energy arbitrage； secondly， it takes account of the life attenuation caused by the cyclic charge and discharge of ESS and builds an optimization model of operation and scheduling to minimize the net cost of distribution networks， and further establishes a storage system configuration optimization model intending to minimize the total cost of energy storage system configuration； then， the optimal configuration model of energy storage is solved by combining genetic algorithm and GUROBI solver to obtain its optimal configuration scheme； finally， the proposed method is simulated and verified by IEEE 33 node system. The results show that the wind and PV generation output power and node voltage fluctuations in the distribution network are significantly reduced under multi-application scenarios； the operational stability of the grid is enhanced while the utilization of the energy storage is improved.

The optimal operation strategy of an integrated energy system is an important means to ensure the economic and stable operation of the system. Given the problem of economic-flexible multi-objective coordination optimization of the integrated energy system （IES）， this paper selects the typical electric-gas-thermal energy system framework and builds mathematical models of system equipment. Taking account of system operation cost and flexibility， this paper proposes IES multi-objective operation optimization strategy considering energy storage life characteristics. The optimal solution of multi-objective problems uses the ε-constraint method， which transforms the secondary objective function into a constraint and then puts it into the solution frame to obtain the Pareto frontier. The optimal operation plan of the IES is determined through fuzzy decision-making. Finally， the proposed model and method are proved feasible by example simulation.

By studying the clutch of parallel hybrid electric vehicle,the state judgment model and working process model based on logic threshold control strategy are established. The operation control principle of clutch in parallel hybrid electric vehicle is analyzed and the control model is set up. The feasibility of the logic threshold control in the clutch control of parallel hybrid electric vehicle is simulated on the Matlab/Simulink platform about clutch state judgment and working process. The result shows that the logic threshold control strategy can effectively judge the working state of the clutch,and then perform the work of shifting,braking and energy switching of the clutch in the parallel hybrid electric vehicle.

Integrated power and heat system (IPHS) is a typical multi-energy system which involves power system and district heating system (DHS). The utilization of thermal flexibilities in the joint operation of power system and district heating system has shown the potential to improve energy efficiency and economic performance. In this paper, an optimal scheduling method for IPHS with multiple thermal flexibilities is proposed. Thermal flexibilities of electric boilers and district heating network (DHN) are modelled and analysed, in which the flexibility of DHN is described by a detailed node-based quasi-dynamic model. The proposed scheduling method is to minimize the operation cost of IPHS. Case study is carried out on a typical IPHS with a 6-node power system and a 12-node DHS. Simulation results show that the scheduling method can reduce the operation cost of IPHS and improve wind accommodation.

Numerical simulation plays a crucial role in polymer processing. This paper analyzes the extrusion of two rubber blends using the Bird-Carreau viscous model and the Phan-Thien-Tanner (PTT) viscoelastic model. The study found that wall slip phenomena occurred in both rubber blends when the apparent shear stress exceeded the critical value. Under these conditions, the physical parameters of the two constitutive models, along with the wall slip parameters that describe the degree of rubber sliding, were obtained. This information provided a theoretical basis for the numerical simulation of the extrusion process. The PTT model was found to be superior to the Bird-Carreau rheological model in predicting the rheological behavior of die swell, velocity field, and pressure field distribution in the extrusion process of the two rubber blends. Highlights * Based on the numerical simulation analysis of the capillary extrusion process, we designed a more feasible method for fitting the physical parameters of the constitutive equation and parameters of the Navier slip model and established the foundation for the subsequent numerical simulation of extrusion processing. * Phan-Thien-Tanner model is proved to be the best candidate for predicting the extrusion of rubber blends with high Mooney viscosity, including die swell, velocity, and pressure distribution. * Demonstrates that wall slip is an important factor in rubber extrusion. * Combining simulation results with experimental data improves the accuracy and predictability of the simulation. KEYWORDS numerical simulation, PTT constitutive equation, rubber melt, wall slip, 1 | INTRODUCTION Because of its excellent vibration-damping and sound-insulating properties, rubber is widely used in the manufacture of tires, inner tubes, and sealing materials for windows, doors, and trucks. [...]

Investigating the phonon-surface scattering mechanism is essential for the evaluation of thermal transport in nanostructures. The theoretical description to quantify this mechanism remains to be developed at the atomic scale. This work presents a phonon wave packet method to study the phonon-surface scattering behavior at rough surfaces. We obtain the specularity distribution dependent on phonon polarization, wavelength, and surface roughness. The reflection of the diffuse wave packet is primarily attributed to the surface shadowing effect at a higher incident angle, surface disorder, and surface-induced localized modes. Taking the wavevector-dependent specularity data as input, the thermal conductivity of silicon nanowires is calculated based on the Boltzmann Transport Equation. Our specularity model provides an accurate evaluation for predicting thermal conductivity. This work offers an atomic-level analysis for phonon-surface interaction, which is helpful for the understanding of thermal transport in nanostructures. [ABSTRACT FROM AUTHOR]