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The rapid advancement of high-tech technologies such as aerospace， electronic information， and biomedicine has required more demands on the properties of advanced ceramic materials. Single-characteristic structural or functional materials cannot meet the current requirements， so the high-performance composite ceramics with integrated structure and function have become global research objectives. Directionally solidified oxide eutectic composite ceramics are a class of structural and functional integrated composite materials developed in recent years for long-term service in ultra-high temperature oxidizing environments. They have characteristics such as high melting point， low density， excellent high-temperature strength， and high-temperature creep performance， while also possessing functional properties such as optics， electromagnetism， and biology. The latest development of directionally solidified structure-function integrated eutectic ceramics was reviewed， specifically focusing on Al2O3-based eutectic ceramic systems. The various preparation methods， technical principles， and growth characteristics associated with directionally solidified eutectic ceramics were summarized. Furthermore， the solidification microstructure and structural characteristics observed in a series of Al2O3-based eutectic ceramics were elaborated. The mechanical， optical， magnetic， and biological properties of composite ceramics and their influencing factors were analyzed， and their characteristics， advantages， and application scope were introduced. Finally， the review summarizes the challenges and key bottlenecks faced by directionally solidified eutectic composite ceramics in engineering applications and proposes the main directions for the development of eutectic composite ceramic materials in terms of forming technology innovation， comprehensive performance improvement， and the development of new systems.

Oxide eutectic ceramics have excellent high specific strength, high temperature resistance, corrosion resistance, oxidation and creep resistance, and so on, which are considered to be the promising materials to be used in ultra-high temperature oxidation, corrosion and other extreme environments. It shows great application prospects in the new generation of high thrust-to-weight ratio aero-engine for high-temperature hot-end structural components. Laser additive manufacturing technology has become one of the most promising cutting-edge technologies for the preparation of high-performance complex structural components in recent years. Crack defect is easy to occur in the process of laser rapid solidification of ceramics, which seriously affects the quality and performance of the oxide eutectic ceramics components. So, it has become a key factor restricting the engineering application. Two typical laser additive manufacturing technologies for ceramics including laser engineered net shaping and laser power bed fusion were briefly summarized. The crack morphology characteristics of different shaped components formed by the above two technologies were analyzed and compared. The formation mechanism of cracks in laser additive manufacturing of oxide ceramics was explored from the perspectives of microstructure characteristics, stress state. Further, a systematic summary was presented focusing on the improvement of microstructures and the reduction of thermal stress to inhibit crack formation through optimization of process parameters, compositional design, and outfield assistance. Finally, it is pointed out that the future development trends and breakthrough directions of oxide eutectic ceramics by laser additive manufacturing in terms of powder properties, forming primary and secondary factors, and forming technology research.

In this study, a new exploration of a classic problem in the field of music aesthetics was carried out through the research methods of cognitive neuroscience and the brain mechanism of the formation of artistic aesthetic value in piano performance based on the theory of multiple intelligences was analyzed. In terms of EEG signal preprocessing, an EEG signal preprocessing method based on baseline average was proposed. In terms of EEG feature extraction, a decision-level feature fusion method is proposed, which uses SVM as the base classifier to extract time-domain, frequency-domain and nonlinear features, respectively, train the base classifier, and integrate the output of multiple basic classifiers through decision fusion. A feature fusion method based on music and ERP was also proposed to predict the response of subjects after listening to a piano performance. Based on DS evidence theory, emotion recognition and classification were carried out using EEG and music features from the perspective of decision-making level fusion. The results showed that piano performance mainly activated the left inferior frontal gyrus, right precentral gyrus, left auxiliary motor area, right superior parietal gyrus, cerebellar Crus1 area, right lingual gyrus and left inferior occipital gyrus, with peak t values of 4.67, 4.8, 5.76, 5.16, 7.02, 7.12 and 8.3, respectively. The activation of auxiliary motor areas, cerebellum, inferior frontal gyrus and other areas indicates that the artistic beauty felt by listening to piano performance can enhance people’s creativity, and the activation of the right superior occipital gyrus can enhance people’s imagination.

Alzheimer’s disease is known as one of the “top ten killers in the world”. Due to lack of effective therapy at present， early pathological changes have captivated widespread attention. Axonal transport dysfunction has been reported as an early pathological feature of many neurodegenerative diseases. However， multiple factors can cause axonal transport dysfunction. In this article， the relationship between axonal transport dysfunction caused by kinesins， microtubules and mitochondria and Alzheimer’s disease was discussed， aiming to provide new ideas for the prevention and treatment of Alzheimer’s disease by in-depth study on axonal transport mechanism of neure.

[Objectives] In order to improve the successful probability of searching for target submarines and to make the operation of the surface ship formation more effectively,the problem about the path planning for the on-call submarine searching for ships is studied.[Methods] Firstly, an on-call submarine searching model of surface ships was constructed based on the Hidden Markov Model(HMM). A two-stage heuristic method was designed to maximize the probability of searching for submarine search expectation. The problem of local optimum was avoided by using evolutionary algorithm(EA)to cross and mutate the individuals in the population,and a comparison with conventional searching methods was made. Then, the effects of different segmentation methods on path optimization were studied experimentally.[Results] The simulation results of single-ship and multi-ship searching for submarines show that the method adopted in this paper can obtain the maximum submarine search expectation and the optimal searching path. The segmentation times experiment show that a reasonable re-division of the search area is beneficial to find a better searching path.[Conclusions] This model can find an optimal path for submarine search and improve the searching efficiency of the surface ship formation.

[Objectives] The sortie generation capacity is an important index of the operational capability of an aircraft carrier and largely determined by the support operation scheduling of the carrier-based aircraft. Therefore a good scheduling of carrier-based aircrafts on the deck can effectively improve the operational capability of aircraft carrier. [Methods] This paper establishes the operation scheduling module by converting the carrier-based aircraft support operation scheduling into job-shop scheduling problem. And through improvement of initial solution, search strategy and tabu list length, an improved tabu search algorithm is proposed to solve the model, with the purpose of minimizing the makespan. [Results] The simulation test results show that the improved tabu search algorithm can solve the carrier-based aircraft support operation scheduling problem effectively, and it is better than the traditional tabu search algorithm in terms of speed calculation and result optimization. [Conclusions] The proposed algorithm provides an effective way to solve the carrier-based aircraft support operation scheduling problem.

[Objectives] Under existing technical conditions, fleet formation is optimized in order to improve the cooperative detection performance of a fleet against hostile submarines. [Methods] The coverage index is defined as a measure of submarine detection ability. Taking a naval combat formation for antisubmarine warfare as the research object, based on the theory of the probability formula of the joint detection performance of multiple ships and taking the maximization of the coverage area as the goal, a formation optimization model based on antisubmarine detection ability is established. An integral optimization method based on the probability distance function is designed to solve the model, and a reasonable formation scheme is obtained. [Results] The simulation results show that the coverage area changes regularly with the variation of the distribution distance of the ship. Under the same fleet size, the detection performance of herringbone formation or wedge-shaped formation is better than that of a single horizontal formation or azimuth team formation under optimal distribution spacing. In addition, the optimal distribution spacing decreases with the increase of the detection probability threshold. As the scale of the fleet increases, the coverage area increases correspondingly in a linear manner. [Conclusions] This model can effectively improve the capability of fleet searching and provide a decision basis for the use and deployment of surface ships in a potential search force.

This paper uses mathematical model theoretical calculation and experimental verification to study the pressure distribution inside the residential kitchen flue and the flow rate of each user through three aspects: temperature difference, opening rate and hood performance. Based on fluid network theory, the flow equation of oil smoke in the cooking exhaust shaft system is established. The accuracy of the mathematical model model was verified through experiments and applied to the calculation of the flue in the kitchen of a 30-story residential building in Shenyang. The results show that the static pressure decreases continuously with the increase of floor height, and the highest pressure appears at the lower level of the floor. The pressure keeps rising as the opening rate increases, i.e., the more users open, the higher the pressure at the bottom floor. Under the joint action of thermal pressure and flue resistance, the static pressure shows a low-high-low distribution form, with the temperature difference increases, the maximum static pressure in the flue moves to the bottom; the flow rate of users on each floor increases with the height, and decreases with the increasing rate of opening, under the influence of thermal pressure user flow distribution is high-low-high distribution.

In order to solve the problem of input fresh air overheating (cooling) in the cold supply (heating) season in severe cold regions, a soil source (BHE) combined with fresh air preheating (cooling) air conditioning system was studied in a net-zero energy building in Shenyang. Firstly, a hybrid TRNSYS-CFD simulation model based on TRNSYS and Fluent simulation software was established to simulate the operation and indoor temperature distribution of the air conditioning system in the building during a typical day in the summer (winter) season. The TRNSYS-CFD hybrid simulation allows simultaneous analysis of the operating characteristics of the air conditioning system and the real-time indoor temperature distribution. The results show that the accuracy of the hybrid simulation is compared with that of the TRNSYS stand-alone simulation by monitoring the temperature changes in each room. The room temperature from the TRNSYS stand-alone simulation is the average temperature of the room return air, while the room temperature from the hybrid simulation has a stratification effect and the simulation data is more valuable for reference.