The pre-stressed concrete (PC) box girder bridge with corrugated steel webs (CSWs) is a new structure, which consists of top concrete and bottom concrete, CSWs, diaphragm plate and internal or external tendon [1, 2]. The PC girder bridge with CSWs adopts the CSWs instead of normal concrete webs, providing light weight, good seismic performance, convenient construction, economical construction management and several other significant advantages. This new type of structure can remove the concrete web cracking and excessive deflection in the mid-span in a large-span continuous beam or continuous rigid frame bridge, and thus improve the durability of the structure. Since the Guangshan Pohe Bridge, the first road bridge with CSWs, was built in 2005, this structure has been used in Henan Weihe Bridge (2010), Jiangxi Chaoyang Bridge (2012), Shanxi Yunbao Yellow River Bridge (2018) and many other places besides [3].

The box girder bridge with CSWs uses a construction technology that is similar to that of the normal concrete box girder bridge, including full framing method, incremental launching method and cantilever casting method. Among them, the full framing method is suitable for construction of small span bridge, and the incremental launching method for construction of medium span bridge with equal height section. For large-span CSW composite box girder bridge with variable section, the cantilever casting method is generally adopted. Motivated by the availability of advanced technology, engineers propose a new construction technology – rapid construction of ripple web (RW), which can be combined with the cantilever casting method. This construction technology originated in Japan, and has been used in more than 30 bridges, including the Tsukumi River Bridge and Kinugawa River Bridge. The optimal performance of these bridges demonstrates the effectiveness of this construction method. Till date, the RW method has been used in the construction of Yunbao Yellow River Bridge and Toudao River Bridge in China.

Ning et al. [4] have discussed the applicability of the RW method in the construction of a continuous girder bridge with CSWs by analysing the means by which this method was applied in the construction of Yunbao Yellow River Bridge, and proposed a limit division of a 4.8 m construction segment. Hui et al. [5] have developed a new type of hanging basket that is suitable for bridges with CSWs, and is in agreement with the structural characteristics of the box girder bridge with CSWs and the construction technology of the RW method. Besides, Mingjun [6] has analysed the normal stress of the top concrete and bottom concrete and the shear stress of the steel webs when the RW construction method was used, and verified the safety of structures constructed using RW. Several bridges constructed using the RW method have shown consistent good performance, demonstrating the advantages of this method; however, the stress status of the steel-concrete junction area is still very complicated during the construction process. Moreover, only very few researches have been carried out ascertaining the reliability of the connection of the shear connector used in the steel-concrete junction area and regarding cracking of the concrete tension area. In this paper, a three-dimensional simulation finite element model was established based on the Zhao-Jun Yellow River Super Large Bridge to discuss the space mechanical behaviour of the bridge with CSWs constructed by the RW method. The present study can be used as a reference for following applications deploying such new construction technology.

The construction of the Zhao-Jun Yellow River Super Large Bridge has contributed to the accumulation of more construction experience in relation to the girder bridge with CSWs in China, because this bridge was built using the new RW method and fully uses the stress characteristics of CSWs. During the construction process, a new hanging basket was used to apply the RW method for the construction of top concrete and bottom concrete. Compared with the rhombic hanging basket, the new means for construction of top concrete and bottom concrete by the RW method provides higher efficiency, greatly shortening the construction period. The main bridge of Zhao-Jun Yellow River Super Large Bridge is expected to be completed by the end of 2021.

The main bridge of Zhao-Jun Yellow River Super Large Bridge is 1,520 m long, with the span combination of 85 m + 9 × 150 m + 85 m. At present, it is the longest continuous girder bridge designed with long spans and CSWs in China. The single width girder is designed with single-box and single-cell slabbing webs, and the left and right width box girders are symmetrical about the centre line of the bridge. The top slab of the single width box girder is 12.75 m wide and 6.75 m wide for the bottom slab. In terms of height, the midspan girder is 5 m and the root girder is 10 m. They transit according to the 1.8-times parabola, and the schematic diagram of the half-span (1/2 span) box girder is shown in Figure 1. The main bridge's box girder adopts a longitudinal and transverse bidirectional prestressed system, and the longitudinal prestressed system of the box girder features a combination of internal and external stresses.

The wave length, wave height and width of the upper structure of the main bridge of Zhao-Jun Yellow River Super Large Bridge are 1.60 m, 0.22 m and 0.43 m, respectively. The horizontal folding angle is 30.7° and the bending radius is 15 t (t is the thickness of the CSW). The CSWs have five thicknesses, namely 16 mm, 20 mm, 22 mm, 25 mm and 28 mm. The standard wave length of CSW is shown in Figure 2.

The CSWs are connected with top concrete by double perfobond rib shear connectors (PBL) at the top of the CSW, which is 25 mm thick and 420 mm wide. It can also be used as the bottom mould for pouring concrete at haunches of box girder. The CSW is connected with the bottom concrete by a 400 mm wide L-shaped 200 × 200 × 18 angle steel. The lower flange steel plate is 22 mm thick, and the angle steel is provided every 0.32 m in the direction of the longitudinal bridge. The connection structure of the main bridge of Zhao-Jun Yellow River Super Large Bridge with CSWs is shown in Figure 3.

As shown in Figure 4, when the PC composite box girder bridge with CSWs is constructed by the traditional hanging basket method, the installation of CSWs, formwork, reinforcement binding of top concrete and bottom concrete and concrete casting in the working area can only be carried out at the n# segment working face, after the hanging basket is installed in place. It only provides a limited working area where many cross operations must be done, thus leading to a longer construction period. However, when the RW method is adopted for pouring construction, the working area is expanded from a single working area to three. These areas are utilised in the following way: top concrete construction can be performed at n# segment working area, bottom concrete construction at n−1# segment working area and installation of CSWs at n+1# segment working area. This can greatly improve the construction efficiency, thus allowing a shorter construction period.

It is worth noting that in the construction process of cantilever casting by the RW method, the position of the basket fulcrum moves forward to the n# segment of the CSWs of the cantilever, which has not yet formed a closed box. In this way, the action arm of the cast girder body is lengthened and the bottom concrete and top concrete weight of one segment are added. Therefore, the inverted ‘

A three-dimensional solid element was used to cause the structure to reasonably and effectively simulate the actual structure of the bridge and the RW construction technology for top concrete and bottom concrete. A fine finite element analysis model of PC composite box girder with CSWs was established using ANSYS, a software of finite element analysis for parallel calculation analysis and comparative review of spatial linear elastic stress. The finite element model of mid-span structure is shown in Figure 5.

In the model, the concrete part adopted an 8-node hexahedral solid element, Solid65; and the CSWs’ part adopted the plate shell element, Shell63. As shown in Figure 4(A), in the solid model of mid-span of Zhao-Jun Bridge, there are 126,512 nodes and 85,592 elements in the whole bridge. In this model, the prestressed steel bars were simulated by using the node coupling method, without considering the ordinary steel bar, the prestressed reduction and the transverse and longitudinal bending of the prestressed pipe. So, the pre-stressed steel bar was 1,395MPa.

The upper and lower flange plates of the CSWs were coupled with the top concrete and bottom concrete at the junction. Given that block 0# was in a consolidated state during the construction process, all degrees of freedom of nodes at the end of the girder were constrained in the model. The flange steel plates of CSWs were connected with concrete co-nodes.

Due to the small area of top concrete, the adoption of node-coupling method for pre-stressing loads will affect the junction of CSWs and concrete. As the stress generated when the prestressed steel is anchored into the concrete is concentrated, the excessive value will disturb the display effect of stress in the concerned area. Besides, the prestressed steer bars in the top concrete are used to avoid the tension of top concrete. Based on the above three considerations, the first principal stress of 0# concrete (cantilever root) was verified after the pre-stress was applied in all construction conditions. If it meets the requirements, the prestressed steel bar is removed, and the stress of CSW and the local stress of tensile top concrete and compressive bottom concrete are emphasised.

In the process of cantilever construction, the built old structure will displace vertically to deviate from the original coordinate position under the action of dead weight and various construction loads. The construction of steel structure requires that the newly installed segment and the installed node should be installed at the interface position to match exactly, corresponding to the tangent pattern in the diagram. When the new component is activated, the corner of the node is considered, and the new component used to simulate the construction step is situated tangentially to the end of the deformed component. During the construction of concrete segments, the position of the subsequent segment formwork is often dynamically adjusted, corresponding to the model modification mode in the figure.

The ANSYS construction process simulation adopted the ‘Element Birth and Death’ [8, 9]. The method of Element Birth and Death is the integration of the formal analysis method on the finite element level. According to the proposed construction sequence, the corresponding construction phase of the component (or element) is ‘activated’, and the corresponding load is applied, after which the simulation analysis of the whole construction process can be tracked.

The Death Element is obtained by multiplying the stiffness and mass matrix of the inactive element by a small coefficient; the Death Element follows the boundary of the Birth Element. However, for large complex structures involving a closed loop, the Death Element often drifts too much, causing the structural configuration to be in a distorted state when the element is activated, which is inconsistent with the unstressed state. Also, the stiffness matrix of the structure is excessively ill-conditioned, leading to the failure of the solution.

Figure 7 shows an example of construction of CSWs using RW. By the traditional step-by-step modelling method, several finite element models are required to be established at different construction stages. However, the Element Birth and Death method pays more attention to the influence on subsequent results after the completion of the previous stage in the construction process. As can be inferred from Figure 7(B), after the construction of concrete load on the crane, all the load falls on the CSWs, which will definitely cause vertical deflection of the CSWs of the cantilever. At this time, the poured concrete will be installed on the corresponding position without stress, along with the deformed CSWs. The principle of the step-by-step modelling method is as follows:

Among them,
_{21} matrix in element 2 (− i.e., the internal force value generated at node 2 when element displacement occurs at node 1).

When the Element Birth and Death method is adopted, the killed element is multiplied by a small coefficient

Eq. (2) can solve the activated element according to Eq. (3) first. At this time, the killed element exists in the form of the equation
_{2} = _{2} and _{3} = _{3}. After expanding the equation, we can get:

It is obvious that there is a mechanical relationship between the second construction stage and the previous construction stage. Therefore, the Element Birth and Death method can make the simulation of construction processes more suitable for the actual project.

According to the reaction force of the support from the separate calculation of the hanging basket, as shown in the table, it was substituted into the finite element simulation model reversely and the calculation results were given based on the working condition of the cantilever (2# top and 3# bottom concrete pouring). The structure load is: box girder weight + basket support reaction.

Under the condition of pouring of girder box by the RW method, its stress state is shown in the figure.

The maximum tensile stress of the CSWs along the bridge is 72 MPa, mainly located in the upper flange steel plate at the junction of the CSWs and top concrete. The maximum compressive stress is 124 MPa, mainly located in the lower flange steel plate at the junction of CSWs and bottom concrete.

The maximum vertical shear stress of the CSWs is 12 MPa, located at the action point of concentrated load. During the construction, the contact area should be appropriately enlarged when the hanging basket acts on the upper flange, and an eccentric load relative to the webs should not occur. The shear stress of the CSWs is about 5 MPa.

The maximum equivalent stress (Mises stress) of the CSWs is 125 MPa, located at the junction of the lower flange steel plate of CSWs and 3# bottom concrete. It meets the requirements of the relevant design specification.

However, since the upper flange steel plate of the CSWs is welded to the CSWs, the welding quality must be guaranteed.

The analysis of the distribution of main stress on the top concrete indicates that 99% of the bottom concrete tensile stress is less than 1 MPa (or in the compressive state), in line with the requirements of the relevant design specifications. The stress concentration in concrete exists in the steel-concrete junction area of a 90° acute angle at the root of the 3# bottom concrete, with the maximum tensile stress of about 4 MPa. The excessive stress here is caused by the corner bending moment that is formed resultant to a tendency of separation between 3# bottom concrete and 2# lining concrete, which can in turn be attributed to the basket load and dead weight. It can be solved by strengthening the structural measures. When necessary, a (prestressed) tie rod can be added between the front cantilever of the 3# bottom concrete and the 2# top concrete to balance part of the load. The tensile stress of concrete at the steel-concrete junction area of the front part of 2# top concrete is about 4.5 MPa. Besides, the upper flange of the CSWs here is subjected to tension, generating a tensile effect on the concrete at the joint position and adding a cracking risk to the concrete. In fact, without adding the upper flange steel plate ‘

In practical engineering, horizontal and oblique cracks can easily occur in the lining concrete section of CSWs. In the Zhao-Jun Yellow River Super Large Bridge, coarse steel bars with JL32 finish rolling thread (area of the bar S = (0.032/2)^{2} × ^{2}) were used to apply the vertical pre-stress. The vertical prestressed steel bars were straight bars, the prestressed bars were replaced using the equivalent load method and the vertical prestressed load was given by: S* 0.9FPK = S* 706.5 Mpa = 568 kN.

As shown in figure, without considering the vertical prestressed bars, the lining concrete is generally subjected to tensile stress, and the red line area is correspondingly subjected to tensile stress. Therefore, there is a cracking risk to the lining concrete. However, when the vertical prestressed bars are considered, the lining concrete is basically in a compression state, which improves its stress state.

The equivalent stress of temporary support is extracted, with the maximum tensile stress of 10.8 MPa. Therefore, the support is safe. A trial calculation of the stable critical stress of the compressive bar of the structure shows it is about 40,000 MPa. It is impossible for the structure to have such a large stress under the action of the hanging basket load, and it is thus free from the instability problem.

During the cantilever construction by the RW method, the CSW was used as the bearing structure of hanging basket (or cantilever), and the pouring of top concrete and bottom concrete and the installation of CSWs were carried out in parallel, which can significantly shorten the construction period and improve the construction efficiency.

The results of the finite element simulative analysis provide the impression that during the cantilever construction using the RW method, the stress of CSWs was lower than that indicated in the standard design requirements, and that stress concentration occurred at the junction of the upper and lower flange steel plates and concrete with CSWs. Therefore, in practice, attention should be paid to the welding quality of CSWs and upper and lower flange steel plates, as well as the construction quality of the perforated steel plate, angle steel and structural steel bar at the junction.

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considering ADC calculation model Analysis of news communication strategies in the era of full media based on big data mining On the improvement, innovation and inheritance of stage makeup styling in opera under the background of big data Recognition of Electrical Control System of Flexible Manipulator Based on Transfer Function Estimation Method Evaluation Mechanism of Teaching Staff’s Building in Local Vocational Colleges Based on Big Data Technology Automatic Knowledge Integration Method of English Translation Corpus Based on Kmeans Algorithm Real Estate Economic Development Based on Logarithmic Growth Function Model Design of Tennis Mobile Teaching Assistant System Based on Ordinary Differential Equations Financial Crisis Early Warning Model of Listed Companies Based on Fisher Linear Discriminant Analysis High Simulation Reconstruction of Crowd Animation Based on Optical Flow Constraint Equation Construction of Intelligent Search Engine for Big Data Multimedia Resource Subjects Based on Partial Least Squares Structural Equation 3D Animation Simulation of Computer Fractal and Fractal Technology Combined with Diamond-Square Algorithm Analysis of the Teaching Quality of Physical Education Class by Using the Method of Gradient Difference The Summation of Series Based on the Laplace Transformation Method in Mathematics Teaching Optimal Solution of the Fractional Differential Equation to Solve the Bending Performance Test of Corroded Reinforced Concrete Beams under Prestressed Fatigue Load Animation VR scene mosaic modeling based on generalized Laplacian equation Radial Basis Function Neural Network in Vibration Control of Civil Engineering Structure Optimal Model Combination of Cross-border E-commerce Platform Operation Based on Fractional Differential Equations The influence of accounting computer information processing technology on enterprise internal control under panel data simultaneous equation Research on Stability of Time-delay Force Feedback Teleoperation System Based on Scattering Matrix BIM Building HVAC Energy Saving Technology Based on Fractional Differential Equation Construction of comprehensive evaluation index system of water-saving irrigation project integrating penman Montei the quation Human Resource Management Model of Large Companies Based on Mathematical Statistics Equations Data Forecasting of Air-Conditioning Load in Large Shopping Malls Based on Multiple Nonlinear Regression Analysis of technical statistical indexes of college tennis players under the win-lose regression function equation Automatic extraction and discrimination of vocal main melody based on quadratic wave equation Analysis of wireless English multimedia communication based on spatial state model equation Optimization of Linear Algebra Core Function Framework on Multicore Processors Research on detection of parking space based on the combination of magnetoresistance and microwave radar sensor under IoT platform Research on sustainable development mechanism of regional ‘Artisan Workshop’ under big data environment Application of hybrid kernel function in economic benefit analysis and evaluation of enterprises The analysis method of the impact of missing audit information on the securities investment decisions based on Logistic regression models Research on the innovation theory of college students’ ideological and political education under the background of big data Research on classification of e-commerce customers based on BP neural network Research on the problems and reform strategies of government statistics based on big data technology The Control Relationship Between the Enterprise's Electrical Equipment and Mechanical Equipment Based on Graph Theory Adaptive fusion of multi-exposure images based on perceptron model Mathematical Modeling and Forecasting of Economic Variables Based on Linear Regression Statistics Exploring the Path of Integrating Excellent Traditional Culture into Civic Education in Universities in the Internet+ Era Nonlinear Differential Equations in Cross-border E-commerce Controlling Return Rate Design and research of environmentally friendly field sewage purification mechanical device 3D Mathematical Modeling Technology in Visualized Aerobics Dance Rehearsal System An analysis of time commitment for college students to online English writing and peer assessment learning Research on network security management monitoring platform based on Internet of things technology Study of frictional wear properties of materials for mechanical seals Fractional Differential Equations in Electronic Information Models Exploring the construction of an all-round cost management system for investment control in university engineering construction BIM Engineering Management Oriented to Curve Equation Model Relationship Between Physical Activity Sedentary Behavior and Body Mass Index in Children and Adolescents Based on FIT Modelo Leakage control of urban water supply network and mathematical analysis and location of leakage points based on machine learning Analysis of higher education management strategy based on entropy and dissipative structure theory Grid data asset relationship and intelligent classification integrating knowledge graph and Internet of Things Prediction of corporate financial distress based on digital signal processing and multiple regression analysis Mathematical Method to Construct the Linear Programming of Football Training Multimedia sensor image detection based on constrained underdetermined equation The Size of Children's Strollers of Different Ages Based on Ergonomic Mathematics Design Application of Numerical Computation of Partial Differential Equations in Interactive Design of Virtual Reality Media Stiffness Calculation of Gear Hydraulic System Based on the Modeling of Nonlinear Dynamics Differential Equations in the Progressive Method Knowledge Analysis of Charged Particle Motion in Uniform Electromagnetic Field Based on Maxwell Equation Relationship Between Enterprise Talent Management and Performance Based on the Structural Equation Model Method Term structure of economic management rate based on parameter analysis of estimation model of ordinary differential equation Influence analysis of piano music immersion virtual reality cooperation based on mapping equation Chinese painting and calligraphy image recognition technology based on pseudo linear directional diffusion equation Label big data compression in Internet of things based on piecewise linear regression Animation character recognition and character intelligence analysis based on semantic ontology and Poisson equation Analysis of digital humanistic knowledge production based on natural language processing Design of language assisted learning model and online learning system under the background of artificial intelligence Study on the influence of adolescent smoking on physical training vital capacity in eastern coastal areas Application of machine learning in stock selection Comparative analysis of CR of ideological and political education in different regions based on improved fuzzy clustering The Construction of Judgment Model for Cultivating Intelligent Accounting Professionals in Universities Based on Logarithmic Periodic Power Law Model Action of Aut( G ) on the set of maximal subgroups ofp -groupsDigital Regeneration and Database Construction of Hunan Embroidery Needlework under the Perspective of Artificial Intelligence Research on the practice of innovation and entrepreneurship education in universities under the environment of big data Application of digital technology in environmental art design Research on loyalty prediction of e-commerce customer based on data mining Research on the evaluation system of tourism management classroom teaching based on multimedia big data analysis The application of ARCS motivation model in college oral English teaching Research on Innovation of Translation Teaching and Translation Strategies for College Students in Multimedia Background A multi-channel convolutional neural network based on attention mechanism fusion for facial expression recognition Exploring the development of cultural and creative tourism under the perspective of ecological theory of tourism destination management Modeling Analysis of User Consumption Data of Internet Culture Industry in the Context of Emerging Technologies Reference: An algorithm for recognizing the main melody of orchestral music based on artificial intelligence of music melody contour Algebraic Equations in Educational Model of College Physical Education Course Education Professional English Translation Corpus Under the Binomial Theorem Coefficient Geometric Tolerance Control Method for Precision Machinery Based on Image Modeling and Novel Saturation Function Retrieval and Characteristic Analysis of Multimedia Tester Based on Bragg Equation Semiparametric Spatial Econometric Analysis of Household Consumption Based on Ordinary Linear Regression Model Video adaptive watermark embedding and detection algorithm based on phase function equation English Learning Motivation of College Students Based on probability Distribution Scientific Model of Vocational Education Teaching Method in Differential Nonlinearity Research on mobile Awareness service and data privacy Protection based on Linear Equations computing protocol Vocal Music Teaching Model Based on Finite Element Differential Mathematical Equations Studying a matching method combining distance proximity and buffer constraints The trend and influence of media information Propagation based on nonlinear Differential equation Research on the construction of early warning model of customer churn on e-commerce platform Evaluation and prediction of regional human capital based on optimised BP neural network Study on inefficient land use determination method for cities and towns from a city examination perspective A study of local smoothness-informed convolutional neural network models for image inpainting The construction of a practical platform for party building and ideological and political education based on information fusion A study on the influence of the spread of Yangming Studies in Japan on the psychology of the Japanese people based on big data analysis Research on personalized recommendation algorithm for micromechanical sensors based on cloud model Research on the value of modern vernacular literature in contemporary rural construction based on ADDIE model Robust speech recognition based on deep learning for sports game review Mathematical Calculus Modeling in Improving the Teaching Performance of Shot Put Model Construction of Influencing Factors of Physical Education Core Quality Cultivation Based on Multiple Linear Regression Application of Nonlinear Differential Equation in Electric Automation Control System Research on the operation and management mechanism of cross-border e-commerce shared practice training base Higher Mathematics Teaching Curriculum Model Based on Lagrangian Mathematical Model Strategies for improving Chinese language proficiency based on artificial intelligence technology The success rate model of college students’ new entrepreneurship based on nonlinear differential equations Computational Algorithm to Solve Two–Body Problem Using Power Series in Geocentric System Research on the application of marketing strategy of national fitness exercise and dance events in the construction of sports culture based on big data technology Decisions of competing supply chain with altruistic retailer under risk aversion Strategies for constructing mathematical models of nonlinear systems based on multiple linear regression models Optimization of Color Matching Technology in Cultural Industry by Fractional Differential Equations Research on human resource management performance evaluation based on BP algorithm The Marketing of Cross-border E-commerce Enterprises in Foreign Trade Based on the Statistics of Mathematical Probability Theory Application of Linear Partial Differential Equation Theory in Guiding Football Scientific Training Nonlinear Channel Estimation for Internet of Vehicles Some Necessary Conditions for Feedback Functions of de Bruijn Sequences The Evolution Model of Regional Tourism Economic Development Difference Based on Spatial Variation Function System Model of Shipping Enterprise Safety Culture Based on Dynamic Calculation Matrix Model An empirical research on economic growth from industrial structure optimisation in the Three Gorges Reservoir area The Inner Relationship between Students' Psychological Factors and Physical Exercise Based on Structural Equation Model (SEM) Analysis and Research on Influencing Factors of Ideological and Political Education Teaching Effectiveness Based on Linear Equation Study of agricultural finance policy information extraction based on ELECTRA-BiLSTM-CRF Fractional Differential Equations in Sports Training in Universities Examination and Countermeasures of Network Education in Colleges and Universities Based on Ordinary Differential Equation Model Innovative research of vertical video creation under the background of mobile communication Higher Education Agglomeration Promoting Innovation and Entrepreneurship Based on Spatial Dubin Model Chinese-English Contrastive Translation System Based on Lagrangian Search Mathematical Algorithm Model Genetic algorithm-based congestion control optimisation for mobile data network Law of interest rate changes in financial markets based on the differential equation model of liquidity Basalt fibre continuous reinforcement composite pavement reinforcement design based on finite element model Satisfactory consistency judgement and inconsistency adjustment of linguistic judgement matrix Badminton players’ trajectory under numerical calculation method Innovations to Attribute Reduction of Covering Decision System Based on Conditional Information Entropy Sensitivity Analysis of the Waterproof Performance of Elastic Rubber Gasket in Shield Tunnel Innovation of Economic Management Risk Control in Retailer Supply Chain Based on Differential Equation Model Statistical Model of College Ideological and Political Learning Based on Fractional Differential Equations Nonlinear Differential Equation in Anti-aging Test of Polymer Nanomaterials Mechanics of Building Structural Materials Based on Lagrangian Mathematical Model Analysis The Mental Health Education Management of Higher Vocational Students Based on Fractional Differential Equations Application of regression function model based on panel data in financial risk management of bank resource allocation University Ideological and Political Learning Model Based on Statistical Memory Curve Mathematical Equation Research on Resonance Properties of Semantic Wave Fractal Fractals Based on Quantitative Analysis of English Corpus Research on urban landscape big data information processing system based on ordinary differential equations Modeling of fractional differential equation in cloud computing image fusion algorithm Conventional Algorithms in Sports Training Based on Fractional Differential Equations Dynamic Nonlinear System Based on Complex System Theory in the Development of Vocational Education The Algorithm Accuracy of Mathematical Model to Improve the Transmission Speed of E-commerce Platform The Security of Database Network Model Based on Fractional Differential Equations Electric Vehicle Mechanical Transmission System Based on Fractional Differential Equations The Practice System of Physics and Electronics Courses in Higher Vocational Colleges Based on Fractional Differential Equations The Economic Model of Rural Supply and Demand Under the Data Analysis Function Based on Ordered Probit 3D Modeling System of Indoor Environment Art Landscape Design under Statistical Equation Electronic Information Security Model of Nonlinear Differential Equations The Optimization Model of College Students' Physical Exercise Motivation and Self-control Ability Based on the Mathematical Model of Probability Theory Health monitoring of Bridges based on multifractal theory Health status diagnosis of the bridges based on multi-fractal de-trend fluctuation analysis Application and risk assessment of the energy performance contracting model in energy conservation of public buildings Sensitivity analysis of design parameters of envelope enclosure performance in the dry-hot and dry-cold areas Criminal law imputation path for biometric information Research on composite dynamic disaster prevention and control system of mine earthquake and shock in thick and hard rock mines Research on urban energy Internet planning based on fuzzy comprehensive method Research on innovative strategies of college students’ English teaching under the background of artificial intelligence Electromagnetic interference prediction technology of new energy motor drive system Research on the intelligent path of college students’ network ideological and political education based on big data mining technology Research on the application of PLC technology in electrical automation engineering Application of matrix multiplication in signal sensor image perception Analysing the variation of metadiscourse verb patterns in English academic papers from within and between disciplines Impact of COVID-19 policy on stock prices of listed property companies Research on the experimental principle of deep integration of LETS software and criminal procedure under the background of artificial intelligence VR-based computer maintenance practical training platform development design and application research Design and implementation of an integrated management system for discipline construction and postgraduate education in universities Research on innovative human capital for China’s economic development based on STI model In-depth analysis of the artistic expression of paper-cut elements in the design of boat space Knowledge graph construction and Internet of Things optimisation for power grid data knowledge extraction Modeling the pathway of breast cancer in the Middle East Construction and intelligent analysis of power grid physical data knowledge graph based on Internet of Things for power system Research on industrial Internet of Things and power grid technology application based on knowledge graph and data asset relationship model Research on the effects of financial literacy on rural household credit constraint Research on educational resource recommendation system based on MRLG Rec Visual analysis of the trend of mental health changes among Chinese college students in the context of the normalisation of the new crown epidemic A study on the phenomenon of anaphoric correction in college students’ English conversation Limit cycles of a generalised Mathieu differential system Influence of displacement ventilation on the distribution of pollutant concentrations in livestock housing Application of data mining in basketball statistics The nonlinear effects of ageing on national savings rate – An Empirical Study based on threshold model Design of fitness walker for the elderly based on ergonomic SAPAD model Research on the innovation of collaborative education model of scientific research and teaching in colleges and universities based on the theory of process reengineering AtanK-A New SVM Kernel for Classification The innovative path of diversified vocal music education reform in colleges and universities under the advanced educational concepts of China and the West Mechanical behaviour of continuous girder bridge with corrugated steel webs constructed by RW Rhino application in ceramic packaging design teaching Study of a linear-physical-programming-based approach for web service selection under uncertain service quality Analysis and countermeasures of cultivating independent learning ability in colleges teaching English based on OBE theory A mathematical model of plasmid-carried antibiotic resistance transmission in two types of cells Projection of Early Warning Identification of Hazardous Sources of Gas Explosion Accidents in Coal Mines Based on NTM Deep Learning Network Burnout of front-line city administrative law-enforcing personnel in new urban development areas: An empirical research in China RETRACTION NOTE Research on the mining of ideological and political knowledge elements in college courses based on the combination of LDA model and Apriori algorithm Research on non-linear visual matching model under inherent constraints of images Good congruences on weakly U-abundant semigroups Can policy coordination facilitate unimpeded trade? An empirical study on factors influencing smooth trade along the Belt and Road Research on the processing method of multi-source heterogeneous data in the intelligent agriculture cloud platform Internal control index and enterprise growth: An empirical study of Chinese listed-companies in the automobile manufacturing industry Research on design of customer portrait system for E-commerce Research on rule extraction method based on concept lattice of intuitionistic fuzzy language Fed-UserPro: A user profile construction method based on federated learning Design and evaluation of intelligent teaching system on basic movements in PE Research on identifying psychological health problems of college students by logistic regression model based on data mining Research on evaluation system of cross-border E-commerce platform based on the combined model A mathematical model of PCNN for image fusion with non-sampled contourlet transform Financial customer classification by combined model Influence of displacement ventilation on the distribution of pollutant concentrations in livestock housing Retraction