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This article, through the method of questionnaire survey and based on the technical analysis of SPSS, investigates the current application of commercial AI in labor education during the transition phase from kindergarten to elementary school. On the basis of analyzing the reasons, corresponding solutions are proposed.

With global warming, environmental degradation is becoming increasingly severe, and the impact on power transmission and transformation equipment is increasing. The changing environment will also have cross impacts, and people are paying more attention to environmental protection. Therefore, under complex environmental conditions, research on new technologies continues, and the emergence of new technologies can improve efficiency and reduce costs. This article focuses on three typical environments: noise environment, soft geological environment, and seismic environment, with a focus on analysing their latest technological situation and management strategies. At the same time, it proposes future development directions, guides the emergence of new business models and service methods, and promotes industry innovation and change.

Low PERMEABILITY RESERVOIR IS AN IMPORTANT MATERIAL FOUNDATION FOR STABLE PRODUCTION IN OLD AREAS, BUT DUE TO THE limitations OF reservoir physical properties, exploitation methods and other factors, the late production effect is poor, therefore, from the reservoir and development approach, the technical measures to improve oil recovery in low permeability reservoir are discussed. Based on the analysis of the factors influencing the development effect of double low reservoir and the geological characteristics of reservoir, from the viewpoint of seepage mechanics, this paper systematically classifies five indexes, such as main pipe radius, flow percentage, starting pressure gradient, clay mineral content and crude oil viscosity. The five-element combination evaluation method is used to optimize the low permeability point reservoir, and on this basis, favorable oil and gas accumulation areas are found. According TO THE DEVELOPMENT status of low permeability reservoir, reasonable injection-production network and well type are demonstrated to break the bottleneck of conventional low permeability water injection and improve the development benefit of low permeability reservoir.

So as to explore the mediator effect of green technologic innovation on the impact of digital economic on circulation industry, based on the panel data of 30 provinces in China from 2011 to 2019, this paper constructs a panel fixed effect model and a mediator effect model for empirical analysis. The results show that the digital economic significantly boosts the advance of the circulation industry; through the mediator effect model test, it is found that the digital economic can boost the advance of the circulation industry through green technologic innovation, and the mediator effect is 57.28 %. Finally, from the aspects of strengthening green technologic innovation, talent support, improving digital economic infrastructure and policy support, this paper puts forward some suggestions on promoting the advance of circulation industry by digital economic.

Liquefied natural gas (LNG) is recognized as the most mature and feasible low-carbon clean alternative energy for ships in the world. Liquefied natural gas is widely favored by ship owners. This paper systematically summarizes the development status of promoting the application of LNG in ships at home and abroad. This paper deeply studies the key technologies of ship LNG power system, and focuses on the comparison of the characteristics of power technology at home and abroad. This paper comprehensively summarizes and analyzes the supporting system for the development of LNG powered ships in China. This paper explores the problems existing in the application of LNG in ships. The paper puts forward a power development path of LNG ships in China in the future. The proposed development path can provide strong support for China to achieve green shipping and dual carbon goals.

With the rapid growth of the global container trade volume and the trend of large-scale container ships. The collection and distribution port efficiency and capacity of container terminals in various countries are facing huge challenges. Due to the randomness of most of the trucks entering the port, container terminals often face the problem of traffic congestion caused by the centralized arrival of trucks in the port and the load operation of the yard operation equipment. Therefore, terminal operators urgently need to manage and optimize all aspects of terminal collection and distribution operations. This paper proposes a truck appointment system that simultaneously considers the time window of the ships and the allocation plan of the yard crans, so as to reasonably allocate the arrival time of each truck and the amount of appointment quota. By means of shortening the time window of each ship’s and rationally allocating the yard cranes operations in the blocks, human and material resources can be fully utilized, so as to alleviate the traffic pressure in the container terminal, shorten the waiting time of ships and trucks, and reduce the cost of terminal operators.

Greenhouse is an important part of facility agriculture and a typical application scenario of modern agricultural technology. The greenhouse environment has the characteristics of nonlinearity, strong coupling, large inertia, and multiple disturbances. There are many environmental factors and it is a typical complex system [7]. In smart greenhouses, control commands are mostly triggered by complex events with multi-dimensional information. In this paper, by building the aggregation structure of complex events in the greenhouse, the technology is applied in the greenhouse as a whole. The core innovations of this paper are as follows: through the analysis of the information transmission process in the greenhouse, combined with the characteristics of the scene, a CEP information structure with predictive modules is formed, which is conducive to the popularization and application of CEP technology in the agricultural field. Pointed out the importance of extreme conditions in the prediction of the greenhouse environment for model evaluation. By improving the loss function in the machine learning algorithm, the prediction performance of a variety of algorithms under this condition has been improved. Applying CEP technology to intelligent greenhouse control scenarios, a set of practical complex event processing systems for greenhouse control has been formed.

This study involved conducting an experimental and numerical investigation on the effects of the air-to-fuel ratio (AFR), engine speed, and engine load on the inlet gas component of a three-way catalyst (TWC) and on the effects of noble metal loading, noble metal ratio, and carrier pore density on the emission conversion efficiency. The results showed that AFR can significantly affect the raw emissions of NOx and THC, and better emission conversion efficiency of a TWC can be reached when AFR is controlled between 0.995 to 1. Compared with engine speed, engine load has a relatively small effect on exhaust temperature but greatly affects the flow velocity and NOx and THC emissions. Increasing the content of Pt in the catalyst can improve the THC conversion efficiency. For low Pt and Pd-Rh catalysts, the THC conversion effect is significantly deteriorated. The content of Rh affects the NOx conversion, and NOx conversion efficiency at high speeds is significantly reduced when Rh content is reduced. Higher carrier pore density can slightly improve the catalytic reaction rate and emission conversion efficiency at high engine speeds. However, high conversion efficiency can be maintained even after aging.

Aiming at that the automatic fault diagnosis method is difficult to locate the fault causes under uncertain circumstances which include malfunctions of the equipment and wrong alarm messages, a knowledge model was proposed to describe the relationship, status and operation of the equipment. And based on the model, the action logic between equipment after accidents is expressed in the form of rules combined with predicate logic. The corresponding interpretation and checking results of the relative alarm messages are given by reasoning the accident chain under different fault hypothesis. And the optimal judgment result is obtained through the calculation of prior probability. The validity of the method is verified by a practical fault case.

As one kind of unconventional natural gas, coalbed methane is an important energy resource that is subject to active research. Gas exists in coalbed methane reservoirs in two forms: free gas and adsorbed gas. In the course of coalbed methane production, the reservoir experiences pressure decrease, desorption, diffusion, and seepage. Previous models of coalbed methane production were mainly concerned with circular boundaries. However, field tests revealed that some fractured wells possess the characteristics of rectangular boundaries. For fractured rectangular coalbed methane reservoirs, it is necessary to deal with the four boundaries with mirror image theory, which complicates calculations. In addition, the desorption and adsorption process of coalbed methane exerts a strong effect on the seepage process. Furthermore, the complexity of the rectangular coal seam embedded with the finite-conductivity fracture results in a significant computational challenge. For the first time, this paper presented a fast analytical solution for a finite-conductivity fractured vertical well model with either rectangular closed or constant-pressure boundaries in the coal seam. On the basis of the Fick diffusion law and the Darcy seepage law, a mathematical model that considers diffusion in matrix and seepage within natural fractures was established. Then, we integrated the fracture conductivity function method with the hydraulic fracture model to greatly increase computational efficiency. The analytical solutions were validated against a numerical simulation. Parameter sensitivity analysis reveals that interporosity coefficient and storage coefficient, respectively, affect the appearance time and degree of desorption and diffusion. Desorption coefficient mainly describes the capacity of desorption and diffusion. Well storage coefficient, conductivity factor, and skin factor mainly affect the early stage of production. Finally, the proposed solutions were applied to field history match. The model developed is applicable to production analysis and well testing for coalbed methane reservoirs. The new proposed model extended flow mechanism of coalbed methane, and provided a better production and pressure forecast for coalbed methane reservoirs. In addition, the analytical solutions can be used to generate type curves for fractured vertical wells with finite conductivity and in the rectangular boundary, and provide a sound theoretical basis for well tests in the coal seam. The model is also applicable to other types of unconventional gas reservoirs, such as gas shales, in which the same processes are present.

Reliability research not only provides the direction of quality improvement for new product research and development, but also helps to get the product failure distribution model, so as to ensure the logistics organization to improve the service level. According to the reliability data from the database of research group, we analyzed the rule of failure distribution of high frequency fault component (fuel injection pump) and built a Weibull model. The parameters of the model are estimated and solved by using the uniform linear method and the least square method. After solving the model, the density function curves and the failure rate curves are drawn, and then the model of the demand forecasting of spare parts based on the failure distribution is obtained.

Based on the standardized modelling of the International Modelling Team, study on double-fed induction generator (DFIG) wind turbine is processed in this paper, aiming at capability of universally and reasonably reflecting key performance related to large scale system analysis. The standardized model proposed is of high degree of structural modularity, easy functional extension and universalization of control strategy and signal. Moreover, it is applicable for wind turbines produced by different manufacturers through model parameter adjustment. The complexity of the model can meet both needs of grid-connected characteristic simulation of wind turbine and large scale power system simulation.

With the development of Distributed Generation (DG), traditional evaluation index of equipment utilization efficiency is not objective in some situations. To solve this problem, a comprehensive evaluation method of equipment utilization efficiency in substation is proposed in this paper. Based on the characteristics of distribution network including DG, two indexes, the burden rate and the load rate, are considered. Then, the indexes are further analyzed that they are specified into the injected indexes and the bidirectional indexes. From the operation data of transformers, the specified indexes are calculated representatively and it is indicated that bidirectional indexes could reflect the equipment utilization efficiency in substation more objectively. The presented method provides a new perspective of evaluating the equipment utilization efficiency in substation considering DG.

Industrial production is a double-edged sword, which not only brings convenience to human beings, but also does some harm to the environment. Water pollution, especially heavy metal pollution, has become a major environmental problem. In this paper, ionization reagent was prepared and attached to cellulose to obtain Cell-IA. The cationic Cell-IA was selected to evaluate the adsorption properties of PBII. The effect of the adsorbent on the actual sewage treatment was studied and whether the adsorbent could be applied in practice was determined.

In this paper, the result based on the techniques of indoor wood adhesive of Camellia oleifera cake and manufacturing of manmade board suggests that the most appropriate condition of preparation this adhesive is that the solid content is 50%, the reaction temperature is 50 °C, the reaction time is 40min, the dosage of PF resin prepolymer accounts for 50 percent. The pH of the reaction medium is 10 and the dosage of SDBS is 1%. The proper conditions hot pressing process of PF Camellia oleifera cake adhesive for bonding plywood are the hot pressing temperature is 120 ℃, and the hot pressing time is 0.7min/mm (42 s / mm), the gluing amount is 120g/m2, and the hot pressing pressure is 1.1MPa. The average water-resistant bonding strength of the plywood prepared under this condition is 0.79mpa, which meets the requirements of class II plate in the national standard GB / T 9846.3-2004. The emission of formaldehyde is 0.38 mg / L, which meets the requirements of class E0 plate in the national standard GB 18580-2001. What’s more, the cost is the lowest among all the techniques.

This paper put forward the inertial control strategy based on the control of charge and discharge of supercapacitor and the trigger angle of H-bridge which integrates photovoltaic (PV) system. The whole cascade H-bridge structure is composed of traditional photovoltaic module, Boost/Buck circuit, supercapacitor (SC), and H-bridge circuit. First, the charging state and the inertial energy power support of the SC are analysed. Then the control strategy of the cascade H-bridge is proposed. To verify the efficiency of the control strategy, a cascade chain consists of 12 H-bridge unit was built in EMTP simulation software. Finally the simulation results prove that the newly developed SC-integrated cascade module can do inertial energy support well, which is important to the coordination between the power system and solar energy.

This article uses panel data from 2000 to 2019 in the China Insurance Yearbook, China Rural Statistical Yearbook and the National Bureau of Statistics. Based on the system generalized moment estimation model, the influence of the density and depth of agricultural insurance at the regional level on the upgrading and optimization of agricultural industrial structure is studied. The empirical results show that the increase in the depth of agricultural insurance has a significant role in promoting the upgrading of the agricultural industry structure. The increase in the density of agricultural insurance has a certain inhibitory effect on the structure of the agricultural industry. Therefore, it needs to improve the agricultural insurance financial subsidy policy, guide the diversified development of agricultural insurance, and establish an agricultural risk reinsurance mechanism to escort the upgrading and optimization of the agricultural industry structure.

In order to promote the green and low-carbon development of ships and promote shipping energy conservation and emission reduction. This paper systematically combed the development of liquefied natural gas (LNG) powered ships in China's inland ships, deeply studied and analyzed the development characteristics of China's new LNG powered ships and reconstructed LNG powered ships, so as to provided reference experience and lay a foundation for China to continue to promote the application of LNG in the water transportation industry in the future.

Since 2010, photovoltaic (PV) was growing rapidly for policy guidance in China. The large-scale PV electricity generation had a great influence on the power grid operation because of the change of the power supply layout. How to analyse the influence is an important matter to power system development. The analysed results will decide the trends of the PV electricity generation in future. Therefore, the Coordination analysis of PV generation growth is crucial to those developments. In this paper, the reasonable plant scale arrangement was discussed based on the difference between peak and valley of power system.

Carbon fibre-reinforced polymer (CFRP) material has a high strength-to-weight ratio and good resistance to corrosion and environmental attacks. It has been widely used in rehabilitation of aged infrastructure. However, the durability of the strengthened system has not been yet assessed thoroughly since most of the previous study was conducted based on accelerated tests while the long-term investigation was less reported. This paper investigated the effect of CFRP wrapping on the axial behaviour of concrete cylinders subjected to different environments for more than 13 years. The specimens were exposed to five different conditions, including standard curing, immersion in distilled water, immersion in saturated Na2SO4 solution, outdoor sheltered from the rain, and outdoor without shelter from the rain. Axial compression tests were performed on the wrapped concrete cylinders. The load-bearing capacity and stress-strain responses were recorded. It was found that CFRP wrapping could effectively improve the ultimate strength and ductility of the columns. Though scatter existed, no significant effect of the environmental exposure on the load-bearing capacity of the cylinder specimens was observed which indicates a good durability of the strengthening system.

College volunteer’s activities are currently linkages between societies and effective way. But the management of the university’s volunteer is more difficulty. In order to effectively address these issues, it is necessary to construct volunteer’s management platform system based on dynamic collaborative task according to the characteristics of volunteers and volunteer characteristics of scientific tasks assigned tasks, and task execution in the entire life cycle of the actual dynamic management, can effectively improve the work efficiency.

The ship-sway is a non-stationary time series while ship sailing in the sea , when using the traditional orthogonal polynomial fitting,index filtering or Kalman filtering to predict ship-sway, the prediction error may be large, because the model parameters are fixed and cannot be adjusted in real time according to the measured data. Multi-level recursive method treats the dynamic system as a time-varying parameters of the system, and can be more in line with the objective reality of rocking the ship. After analyzing the characteristics of the ship-sway, the predict model established by multi-level recursive has been built and test results showed that this model can improve the prediction accuracy of the ship-sway data, and has some practical value in the prediction of the ship-sway.

The use of composite materials, such as carbon-fiber reinforced plastic (CFRP) composites, aero-structures has led to an increased need of advanced assembly joining and repair technologies. Adhesive bonded repairs as an alternative to recover full or part of initial strength were investigated. Tests were conducted with the objective of evaluating the effectiveness of techniques used for repairing damage fiber reinforced laminated composites. Failure loads and failure modes were generated and compared with the following parameters: scarf angles, roughness of grind tool and number of external plies. Results showed that scarf angle was the critical parameter and the largest tensile strength was observed with the smallest scarf angle. Besides, the use of external plies at the outer surface could not increase the repairs efficiency for large scarf angle. Preparing the repair surfaces by sanding them with a sander ranging from 60 to 100 grit number had significant effect on the failure load. These results allowed the proposal of design principles for repairing CFRP structures.