The concept of building assembly originated from the Japanese construction industry in 1964, it is intended that through modern industrial production methods, in order to change the past residential production mode, achieve the purpose of improving construction efficiency, saving resources, protecting the environment, and promoting the modernization development process of the construction industry. From the concept, we can see that “building assembly” involves a wide range of aspects, it covers the design of the entire residential life cycle, the production of components, on-site construction and subsequent operations. Compared with the traditional design, construction and production, it pays more attention to the introduction of advanced technology and management methods. Thus we can see from this that, the most important thing in the implementation of building assembly is still the improvement of technology and management level [1].
Building houses through industrialization can be called prefabricated buildings. Industrial production methods are used to reduce energy consumption and material consumption, reduce costs, improve residential quality, and improve labor productivity in residential production. By promoting the standardization of design, the industrialization of component processing and the standardization of the entire construction process, the industrialization of residential construction is realized. The industrial chain of prefabricated building system includes the following three main steps: standardization and standardized design, production of factory components, and assembly construction according to the design plan [2].
High energy consumption, high material consumption and high pollution are the important defects of traditional residential production methods, that is, the “three highs” problems we often say. According to the statistics of the environmental protection department, about 30% of the production and use energy consumption is used for building production every year, and if measures are not taken in time, the proportion will be even higher in the future. With the development and progress of society, especially in the environment where the country vigorously advocates sustainable development, even key indicators such as GPD are no longer required, as an important part of the national economy, the construction industry needs to take corresponding measures to contribute to the rapid and sound development of the economy. In such a big environment, it is imperative to upgrade the building assembly in the real estate industry. It can greatly reduce the problems of high pollution, high material consumption and high energy consumption caused by residential production. At the same time, the introduction of advanced production technology and management experience can make use of less resources, bring a more scientific and comfortable life experience to the residents [3].
Wu, G. and others believe that the Residence Function Technique has always been the focus of research on building assembly in the United States, for example, NASA hopes to apply the advanced technology of spacecraft to the construction of residential buildings. The fundamental starting point of housing should be to meet human needs, so fundamentally speaking, the research on building assembly is to use modern housing production technology to meet the needs of households [4]. Li, J. et al. found that experts from the French Ministry of Housing, after reviewing many houses, a series of “construction systems” have been determined, which greatly reduces the specifications of components and simplifies construction and installation. It is worth noting that among the 25 types of housing proposed by the French jury, a considerable part of them are precast concrete systems, this also provides professional technical support for the author to study the key technologies of building assembly, represented by the concrete precast system [5]. Sun, J. and others believe that “assembled houses” have always been people's dreams, and people have long expected that houses can be built like building blocks, build it your own way. Australian architects have made this dream come true with the help of new cold-formed steel and “Rapid Wall” technology. It is believed that with the continuous overcoming of related technical problems, “assembled houses” will be more widely used [6]. Qing, Kang et al believe that there are many restrictive factors in the current stage of building assembly in China, this not only limits the comprehensive development of building assembly, but also limits the enthusiasm of the academic community for building assembly research. But fortunately, under such difficult circumstances, the development of building assembly in China has still achieved considerable results, especially at the technical level [7].
Precast concrete composite floor is one of the most commonly used floor forms for prefabricated steel structure houses, and it is also the first research content in the floor system. It has good integrity, crack resistance, earthquake resistance and thermal insulation performance. The advantages of simplicity, shortened construction period, no need for formwork, material saving, and mechanized production make this floor system more widely researched and applied, and fully conforms to the development direction of the integration of prefabricated steel structure housing.
Precast concrete composite floor is an integral floor system formed by prefabricated base plate as formwork and pouring concrete on its surface. The prefabricated floor can be equipped with ordinary steel bars, steel strands, prestressed steel bars, etc. to improve the strength of the prefabricated floor. According to the structural requirements, the transverse distribution of steel bars is appropriately configured.
The prefabricated slab part of the prefabricated concrete composite floor slab is generally processed and produced in the factory according to the requirements of standardization and scale, and then transported to the construction site, where a layer of concrete is poured on the surface to make it an integral structure. This combination form has obvious advantages over other floor slab systems, especially in the case of very difficult formwork support in high-altitude working conditions. The floor slab and the steel beam are generally connected by shear connectors. For developing new connection forms and improving the bearing capacity of the components, the production in the factory is also more convenient and easy to complete, which reflects another advantage of this kind of floor slab in construction..
The normal span of the laminated floor is 4–6m, and the maximum is 9m. Laminated slabs can be designed as two-way slabs or one-way slabs. For boards supported on four sides, when the ratio of the short side to the long side is less than 2 or between 2 and 3, it shall be calculated according to the two-way board; when the ratio of the short side to the long side is greater than 3, it shall be calculated according to the one-way board. Computation [8].
In the process of parallel splicing of one-way slabs, additional reinforcement bars that are perpendicular to the slab joints should be arranged at the joints. The diameter of the additional reinforcement bars should be greater than 6mm, the spacing should be less than 250mm, and the cross-sectional area is larger than the area of the reinforcement bars in this direction in the prefabricated slab; The anchorage length of the post-cast concrete superimposed layer extending into both sides should be greater than 15d (d is the diameter of the additional steel bar) [9].
The design value of the bearing capacity of the composite beam is calculated according to formula (1):
The prefabricated part and the cast-in-place part of the composite beam can adopt the plane interface and the bottom interface. When a plane interface is used, the thickness of the cast-in-place part of the main beam is generally not less than 150mm, and the secondary beam is generally not less than 120mm; When using a concave interface, the depth of the notch is generally not less than 50mm, and the thickness of the edge of the notch is not less than 60mm.
The root of the composite beam is a shear sensitive area, and the requirements for structural shear resistance are high, the design of stirrups can take the following two forms.
When the seismic grade is Class I or Class II, the reinforced area of the beam end stirrups of the superimposed frame beams should be in the form of integral closed stirrups; When combined closed stirrups are used, the stirrups above the open stirrups of the prefabricated part of the superimposed beam should be made into 135. Hook; For non-seismic design, the length of the straight section at the end of the hook should not be less than 5d (d is the same below the diameter of the steel bar), at present, there are few buildings with non-seismic design, and this design form is not commonly used; In seismic design, the length of the straight section should not be less than l0d [10].
When the composite beam is required by design, it can take the form of butt connection. When the composite beams are butted, there should be enough operating space between the two prefabricated beams, the joints of longitudinal reinforcement can be in the form of mechanical connection, sleeve grouting connection or welded connection. The stirrups in the post-cast section should be encrypted.
The design of the prefabricated column is relatively simple, it belongs to a single component, and there is no overlapping problem. Only the upper and lower end requirements of the column need to be considered in terms of construction for prefabricated construction.
Prefabricated columns should be designed according to the current national standards and requirements of the “Code for Design of Concrete Structures” GB 50010. In addition, the following points should be paid attention to in the process of prefabricated construction: First, when connecting the longitudinally stressed steel bars of the columns through sleeve grouting, the length of the reinforced area of the column stirrups should be greater than the sum of the length of the longitudinally stressed steel bar connection area and 500mm; the distance between the first stirrup at the upper end of the sleeve and the top of the sleeve should be less than 50mm; the second is that the diameter and width of the rectangular column section should be greater than The width of the beam in the same direction is 1.5 times and greater than 400mm; the third is that the diameter of the longitudinal reinforcement of the column should be greater than 20mm.
At present, in the seismic codes of various countries, for irregular plane and vertical irregular structures, generally, the equivalent static method or the torsional accident combined vibration type decomposition response spectrum method is used, conduct seismic response analysis, according to the combination principle of SRS S method and CQC method, in order to obtain the torsional earthquake response of the eccentric structure under the action of the horizontal earthquake, these are the analysis methods in the elastic stage; And for the elastic-plastic dynamic analysis of the eccentric structure, it is difficult to start from both theoretical and experimental aspects, and the work in this area is still limited to relatively superficial content.
For the upper eccentric structure model, according to the results of a long-term study. Generally, two models are used for correlation analysis: Tandem particle system and tandem rigid plate system. The series of mass points is equivalent to concentrating the mass of each floor to one point, and each particle has two degrees of freedom in the horizontal direction; the series of rigid plates, considering the eccentricity of the structural floor, simplify each floor as a rigid piece model, then each rigid piece includes three degrees of freedom, namely two horizontal translations and twists around the vertical axis.
Calculate the plane layout of the model, the moment of inertia of the upper eccentric structure:
The translational stiffness in the
The floor torsional stiffness at the center of mass is:
Eccentricity:
Among them:
Project name Weihai Wanghaiyuan Middle School Project, located on the east side of the school in Huancui District, Weihai City is Tashan Middle Road, on the south side is Jiaozhou Road, on the west side is Planning Unified South Road, and on the north side is Chengyang Road. The construction unit is the Education Bureau of Huancui District, Weihai City, and it will be delivered to Weihai Wanghaiyuan Middle School for use after completion and acceptance. This project was designed by Weihai Architectural Design Institute Co., Ltd., and general contracted by Weihai Construction Group Co., Ltd. The author personally organized the construction of this project as the project leader.
The Weihai Wanghaiyuan Middle School project includes the comprehensive teaching building in the south area and the arts and sports center in the north area, with a total construction area of 44,500m2. Among them, the South District Comprehensive Teaching Building has 2 underground floors and 4 floors above ground, with a construction area of 29755m2; The North District Art Center has 1 underground floor and 5 floors above ground, with a construction area of 14745m2.
The structure type of this project is prefabricated concrete frame structure, and the main prefabricated components are concrete laminated floor slabs. Among them, four construction sections use prefabricated laminated floor slabs, with a total laminated area of 5600m2. The laminated board was designed by Haishi Tongwei Construction Technology Co., Ltd. and confirmed by Weihai Architectural Design Institute Co., Ltd.
The prefabricated laminated panels in this project are all one-way panels. The maximum weight of a single laminated board is 1.20T, and the concrete strength grade is C30. The construction method of the laminated floor slab is as follows: The thickness of the prefabricated laminated board is 60mm, and the thickness of the upper cast-in-place slab is 70mm. C30 concrete = soil pouring is used, the prefabricated board is produced by a manufacturer with professional construction qualifications.
Prefabricated components, all kinds of materials and equipment will enter the site according to the construction sequence, and they will be sorted and stacked, the stacking area of the on-site laminated board is mainly stacked on both sides of the temporary road on the south side and in the middle patio for centralized stacking. There are many types of laminated boards in this project, and the number reaches 86, on-site sorting is more troublesome, we have contacted the supplier in advance, during the production process, the trucks are loaded into the yard in the order of the hoisting direction, and the stacking area in the yard is stacked in order according to the order of hoisting.
The approach route of the vehicles transporting prefabricated laminated panels needs to be fully hardened, and the vehicles will be lifted and unloaded by tower cranes near the component stacking area, warning lines and warning signs are set up in the hoisting area. The prefabricated components are placed in the prefabricated stacking area, and the stacking area is 7cm thick C15 concrete hardened. The prefabricated components shall be horizontally layered, typed and numbered, and the stacking height of each stack shall not exceed 6 layers, considering the effect of concentrated load, the bottom one of the dunnage is long, and the layers should be leveled and compacted. The stacking spacing of the laminated plates is not less than 50cm, which is convenient for people to pass, and ensures that they will not collide with each other and cause damage during the hoisting process [11].
The bottom support system of the composite slab of the residential building of this project is a fastener steel pipe support system, which is composed of a steel pipe frame, a wooden square bracket, and a top wire, the scaffolding is erected in accordance with the formwork support plan, the beam side is supported with a 400-wide formwork handover area, and the spacing between the wooden squares in the middle is 500mm.
According to the floor control line and the plan layout of the support frame, the on-site surveyor will set out the position of the floor wall column and the frame body layout, and then erect the frame body.
In this project, steel pipe scaffolding is used under the laminated board, in order to ensure the safety of the support and the safety of the hoisting workers, the full-floor support is erected with the cast-in-place roof. In this project, the span of the laminated board is 3100mm, the vertical and horizontal spacing of the poles is lm, and the step distance of the scaffolding is 1600mm.
The construction personnel use the horizontal ink line instrument and the steel tape measure to pass the height of the top wire at the top of the support frame, adjust the height of the vertical pole up and down, so that the top elevation of the steel pipe keel is equal to the bottom elevation of the designed laminated plate. The steel pipes used should be straight and without visible bending, after the support is completed, the elevation of the top of the bracket should be measured at each position of the bracket to ensure that it is consistent with the design elevation of the bottom of the prefabricated slab.
According to the on-site floor control line and detailed design drawings, using steel tape measure, theodolite, horizontal ink line meter and other instruments, the position of the laminated board is bounced on the beam template to locate the position of the laminated board.
In order to ensure the accuracy of the hoisting of the laminated board, communicate with the laminated board manufacturer, during the production process of the laminated board, a control line that overlaps with the floor control line is left at the bottom of the laminated board, during the hoisting process of the laminated board, the ground control line is projected onto the top laminated board by a laser ink line instrument, and the positioning of the laminated board is completed as long as the two lines overlap.
Before installing the laminated floor, please pay attention to the following matters:
The laminated board extends into the beam by 10mm, and some floor formwork is supported on the side of the beam, the width of the formwork is 300, the position of the laminated board is set out on the formwork on the side of the beam, which is convenient for hoisting the laminated board floor. After this part of the formwork support is completed, the secondary elevation check is carried out immediately to ensure that the height of the formwork is consistent, so as to ensure that the elevation of the laminated board after hoisting is consistent. Copy and lay out the line, copy the +1 meter horizontal line on the wall column steel bar, and make a clear mark, the bottom formwork of the laminated board is checked and accepted, and the elevation size is strictly controlled, in order to control the installation elevation and plane position of the laminated board, avoid secondary lifting to adjust the position.
When the laminated board is lifted, the bending moment caused by its own weight should be reduced as much as possible, and the prefabricated member lifting beam should be used for lifting, laminated board lifting slings are customized and provided by the laminated board manufacturer, in order to meet the needs of the hoisting of the laminated board, the hoisting of the laminated board adopts 4/6 lifting points to ensure uniform stress and ensure the stable hoisting of the components, the position of the lifting point shall be clearly marked on the approach stack, and the lifting shall be carried out in strict accordance with the marked lifting point.
Before hoisting, a trial hoisting should be carried out, and the suspension should be carried out at a distance of 50 cm from the ground to ensure that the laminated board is in a balanced state, and the stress of the hook and wire rope should be carefully checked, and finally hoisted to the top of the working layer [12]. The optimization results are shown in Table 1.
The genetic optimization results of the remaining prefabricated composite beams are as follows:
Name | Size information | strength grading of concrete | |||||||
---|---|---|---|---|---|---|---|---|---|
Prefabricated folded version 3360mm*2800mm | 50mm | 9 | 9 | 12 | 9 | 8 | 175.6042 | 189.7462 | C30 |
Prefabricated folded version2330mm*2280 mm | 50mm | 9 | 9 | 12 | 9 | 12 | 156.3652 | 186.0354 | C30 |
After being in place, the installation of the laminated board must be carried out vertically from the top down, and it should be suspended at 200mm above the working layer. The construction personnel will align the edge of the laminated board with the placement position line on the formwork on the side of the beam, and can adjust the direction appropriately by holding the floor. In order to avoid the staggering of the beam steel bars and the reserved steel bars on the laminated board, pay attention not to be too fast when lowering, but to stop and lower it slowly, so as not to cause cracks on the board surface due to excessive impact force. When the wind is above level 5, hoisting is not allowed.
Professional manufacturers provide special slings, The slings should be specially designed, the specifications of the slings meet the requirements, the horizontal angle of the slings should not be less than 45 degrees, and should not be less than 60 degrees.
During the hoisting process of the laminated board, the construction shall be stopped within the falling radius of the crane, and the hoisting radius shall be surrounded by ribbons, and full-time safety personnel shall be arranged to supervise the station.
After the hoisting of the laminated board is completed, the laying and connection of the water and electricity pipelines shall be carried out, in order to facilitate the construction, in the production stage of the laminated board, the corresponding wire boxes and reserved openings should be embedded in the prefabricated board according to the design drawings, in order to facilitate the connection of the wires and pipes on the laminated board, the octagonal wire box is used for the pre-embedded design of the wire box.
Before the pipeline laying, the installation department and the project technical department do a good job in the detailed design of the pipeline laying, minimize the phenomenon of pipeline fights, if the radiation pipeline cannot be constructed, it is necessary to cut off the self-contained ribs of the laminated plate, the technical personnel must communicate with the design unit, and do a good job in reinforcing the steel bars at the cut-off parts, and ensure the thickness of the protective layer of the upper steel bars. During the construction process, all parties must do a good job in protecting the finished product.
During the construction process, if the superimposed part of the line pipe installed in some parts exceeds the reinforced bar, the line pipe will first pass through the cast-in-place beam, avoid the junction part, and then connect the octagonal box.
When the superimposed floor concrete of this project is poured, it shall be poured in the order from the middle to the two sides. The optimization results are shown in Table 2 and Table 3.
Genetic optimization results of other prefabricated composite beams
Name | Size information | Force reinforcement | Waist tendons | stirrup | Encryption area spacing | Non-encrypted zone spacing | strength grading of concrete | |
---|---|---|---|---|---|---|---|---|
Wide | Tall | |||||||
Main beam: 6,030 mm (not connected to the secondary beam) | 450mm | 520mm | 26 | 11 | 9 | 115.2215mm | 215.5053mm | C30 |
Main beam: 7,230mm (connected to the secondary beam) | 450mm | 520mm | 26 | 11 | 9 | 55.0456mm | 223.5623mm | C30 |
Genetic optimization results of other prefabricated composite beams
Name | Size information | Force reinforcement | Waist tendons | stirrup | Encryption area spacing | Non-encrypted zone spacing | strength grading of concrete | |
---|---|---|---|---|---|---|---|---|
Wide | Tall | |||||||
Main beam: 6,030mm (not connected to the secondary beam) | 450mm | 520mm | 25 | 12 | 9 | 112.9523mm | 220.2647mm | C30 |
Main beam is 1,700 mm | 240mm | 38mm | 18 | / | 9 | / | 126.2514mm | C30 |
Secondary beam: 1220mm | 240mm | 380mm | 18 | 9 | / | 118.3571mm | C30 |
At the connection between the superimposed floor and the surrounding cast-in-place concrete floor, the vibration should be strengthened when pouring concrete. After the concrete pouring of the floor is completed, the cable is closed, and the elevation of the wall and column is strictly controlled, which is not greater than 5mm of the structural elevation. The concrete pouring of the floor slab is uniformly distributed by the automobile pump, and it is arranged according to each flow section. Concrete surface layer curing is completed after pouring, and the content requirements for pouring and curing of the concrete construction plan on the ground are the same.
When the formwork and supports are removed, they should be removed evenly from the middle to both sides; After the compressive strength of the post-cast concrete of the superimposed floor slab meets the design requirements, the keel and the support of the next layer can be removed before the keel is removed, when there is no design requirement, the removal time requirements in the table below shall be met. After the upper concrete construction is completed, the lower formwork and supports can be removed.
Before the concrete is poured, the joint position of the upper laminated board should be treated. Communicate with the laminated board manufacturer, and leave a 50-wide tongue and groove on each side of the stubble position of the laminated board, after the concrete on the top of the laminated slab is poured, use special plastering mortar to plaster the surface, and hang glass fiber mesh cloth to prevent cracking.
Based on the concrete structure prefabricated building in the Weihai Wanghaiyuan Middle School project undertaken by Weihai Construction Group Co., Ltd., the application of prefabricated building related technologies in engineering is discussed. The building has carried out the secondary design of prefabricated components on the basis of traditional structural design, which opens up new ideas for the design of prefabricated buildings. In terms of construction, through comparative analysis, reasonable construction techniques have been adopted in the aspects of stacking, hoisting, reinforcing steel bars, concrete pouring and plate-to-plate connection, during construction, attention was paid to the details of key technologies. Through engineering practice, we have a clearer understanding of the design and construction of prefabricated buildings, and a deeper understanding of related technologies, and also verified the feasibility of related technologies in engineering [13].
The author's realization of design standardization is the premise and foundation of building assembly. The author carried out the structural design of the prefabricated composite slabs, composite beams, prefabricated columns, prefabricated shear walls and other components involved in the prefabricated concrete structure system, the structural design scheme is given, and the connection between the components is designed, the construction scheme of component connection is given. The design and comparative analysis of waterproof, sealing and other aspects have been carried out, and the whole prefabricated building design scheme has been formed, it laid the foundation for the promotion of prefabricated buildings. The transportation and assembly of the components are the decisive links in the quality of the prefabricated building, the technical details of the transportation, stacking, installation and other processes in the construction process are discussed in detail, the construction process of the installation and construction of different components is formulated, the key technical indicators are determined, and the mechanical check calculation method to ensure the quality of the components is given, which provides a guarantee for the construction quality.
All in all, the main reason for the slow development of prefabricated buildings in my country in recent years is its high construction cost, so reducing the construction cost of prefabricated buildings is the key to its forward development. Enterprises should strengthen management, establish and improve various modular standards and component product standards. Through these standards, it is a prefabricated construction of a unified assembly line factory production to reduce the prefabrication cost of construction. On the other hand, in engineering practice, it is necessary to continuously optimize the structural design of prefabricated buildings, improve construction technology, improve project quality and efficiency, reduce construction costs, and promote the continuous innovation and development of prefabricated buildings.
Genetic optimization results of other prefabricated composite beams
Name | Size information | Force reinforcement | Waist tendons | stirrup | Encryption area spacing | Non-encrypted zone spacing | strength grading of concrete | |
---|---|---|---|---|---|---|---|---|
Wide | Tall | |||||||
Main beam: 6,030mm (not connected to the secondary beam) | 450mm | 520mm | 25 | 12 | 9 | 112.9523mm | 220.2647mm | C30 |
Main beam is 1,700 mm | 240mm | 38mm | 18 | / | 9 | / | 126.2514mm | C30 |
Secondary beam: 1220mm | 240mm | 380mm | 18 | 9 | / | 118.3571mm | C30 |
The genetic optimization results of the remaining prefabricated composite beams are as follows:
Name | Size information | strength grading of concrete | |||||||
---|---|---|---|---|---|---|---|---|---|
Prefabricated folded version 3360mm*2800mm | 50mm | 9 | 9 | 12 | 9 | 8 | 175.6042 | 189.7462 | C30 |
Prefabricated folded version2330mm*2280 mm | 50mm | 9 | 9 | 12 | 9 | 12 | 156.3652 | 186.0354 | C30 |
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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 Paris panxiensis , a new combination of Trilliaceae from Sichuan, ChinaImpact of ASEAN-China free trade area on fishery value chain based on difference-in-difference method 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 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 application of PLC technology in electrical automation engineering Research on indoor environment design of comprehensive commercial shopping center based on numerical simulation Application of matrix multiplication in signal sensor image perception Empirical analysis of the economic absolute income hypothesis based on mathematical statistics 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 Realization of Book Collaborative Filtering Personalized Recommendation System Based on Linear Regression Equation Research on the experimental principle of deep integration of LETS software and criminal procedure under the background of artificial intelligence Study on Interactive Relations between Enterprise Social Media and Decision Style Based on a vector Autoregressive Model Research on Dynamics of Flexible Multibody System with Deployable Antenna Based on Static Lagrangian Function The Optimization of Mathematics Teaching Models in Colleges and Universities Based on Nonlinear Differential Equations Study on spatial planning and design of learning commons in university libraries based on fuzzy matrix model The Stability Model of Piano Tone Tuning Based on Ordinary Differential Equations Construction and application of automobile user portrait based on k-mean clustering model The Homework Model of Screening English Teaching Courses Based on Fractional Differential Equations VR-based computer maintenance practical training platform development design and application research 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 Calculus Logic Function in Integrated Manufacturing Automation of Single Chip Microcomputer Football Offense Training Strategy Based on Fractional Differential Mathematical Modeling Research on educational resource recommendation system based on MRLG Rec The Mathematical Analysis Model of Educational System in Music Courses in Colleges and Universities Continuing Education Network Data Center Model Based on Fractional Differential Mathematical Equations A study on the phenomenon of anaphoric correction in college students’ English conversation Computer Art Design Model Based on Nonlinear Fractional Differential Equations The Optimization Model of Public Space Design Teaching Reform Based on Fractional Differential Equations The Approximate Solution of Nonlinear Vibration of Tennis Based on Nonlinear Vibration Differential Equation Graphical Modular Power Technology of Distribution Network Based on Machine Learning Statistical Mathematical Equation Employment and Professional Education Training System of College Graduates Based on the Law of Large Numbers Economic Research on Multiple Linear Regression in Fruit Market inspection and Management Nonlinear Differential Equations in Preventing Financial Risks Lagrange’s Mathematical Equations in the Sports Training of College Students Simulation Research of Electrostatic Precipitator Power Supply Voltage Control System Based on Finite Element Differential Equation Research on the effect of generative adversarial network based on wavelet transform hidden Markov model on face creation and classification Research on Lightweight Injection Molding (CAE) and Numerical Simulation Calculate of New Energy Vehicle Power Flow Calculation in Smart Distribution Network Based on Power Machine Learning Based on Fractional Differential Equations Demonstration of application program of logistics public information management platform based on fuzzy constrained programming mathematical model Basketball Shooting Rate Based on Multiple Regression Logical-Mathematical Algorithm The Optimal Application of Lagrangian Mathematical Equations in Computer Data Analysis Similarity Solutions of the Surface Waves Equation in (2+1) Dimensions and Bifurcation Optimal decisions and channel coordination of a green supply chain with marketing effort and fairness concerns Game theoretic model for low carbon supply chain under carbon emissions reduction sensitive random demand 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 AtanK-A New SVM Kernel for Classification Mechanical behaviour of continuous girder bridge with corrugated steel webs constructed by RW Study of a linear-physical-programming-based approach for web service selection under uncertain service quality The Relationship Between College Students’ Taekwondo Courses and College Health Based on Mathematical Statistics Equations 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 Fractional Differential Equations in the Exploration of Geological and Mineral Construction AdaBoost Algorithm in Trustworthy Network for Anomaly Intrusion Detection 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 Enterprise Financial Risk Early Warning System Based on Structural Equation Model A Study on the Application of Quantile Regression Equation in Forecasting Financial Value at Risk in Financial Markets Fractional Differential Equations in the Model of Vocational Education and Teaching Practice Environment Information transmission simulation of Internet of things communication nodes under collision free probability equation Image denoising model based on improved fractional calculus mathematical equation Random Fourier Approximation of the Kernel Function in Programmable Networks The Complexity of Virtual Reality Technology in the Simulation and Modeling of Civil Mathematical Models University Library Lending System Model Based on Fractional Differential Equations Calculation and Performance Evaluation of Text Similarity Based on Strong Classification Features Intelligent Matching System of Clauses in International Investment Arbitration Cases Based on Big Data Statistical Model Evaluation and Verification of Patent Value Based on Combination Forecasting Model Financial Institution Prevention Financial Risk Monitoring System Under the Fusion of Partial Differential Equations Prediction and Analysis of ChiNext Stock Price Based on Linear and Non-linear Composite Model Calculus Logic Function in Tax Risk Avoidance in Different Stages of Enterprises The Psychological Memory Forgetting Model Based on the Analysis of Linear Differential Equations Optimization Simulation System of University Science Education Based on Finite Differential Equations The Law of Large Numbers in Children's Education Optimization System of Strength and Flexibility Training in Aerobics Course Based on Lagrangian Mathematical Equation Data structure simulation for the reform of the teaching process of university computer courses 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 A multi-factor Regression Equation-based Test of Fitness Maximal Aerobic Capacity in Athletes Design and evaluation of intelligent teaching system on basic movements in PE Garment Image Retrieval based on Grab Cut Auto Segmentation and Dominate Color Method Financial Risk Prediction and Analysis Based on Nonlinear Differential Equations Constructivist Learning Method of Ordinary Differential Equations in College Mathematics Teaching Multiple Effects Analysis of Hangzhou Issuing Digital Consumer Coupons Based on Simultaneous Equations of CDM Model Response Model of Teachers’ Psychological Education in Colleges and Universities Based on Nonlinear Finite Element Equations A Hybrid Computational Intelligence Method of Newton's Method and Genetic Algorithm for Solving Compatible Nonlinear Equations Pressure Image Recognition of Lying Positions Based on Multi-feature value Regularized Extreme Learning Algorithm English Intelligent Question Answering System Based on elliptic fitting equation Precision Machining Technology of Jewelry on CNC Machine Tool Based on Mathematical Modeling Application Research of Mathematica Software in Calculus Teaching Computer Vision Communication Technology in Mathematical Modeling Skills of Music Creation Based on Homogeneous First-Order Linear Partial Differential Equations Mathematical Statistics Technology in the Educational Grading System of Preschool Students Music Recommendation Index Evaluation Based on Logistic Distribution Fitting Transition Probability Function Children's Educational Curriculum Evaluation Management System in Mathematical Equation Model Query Translation Optimization and Mathematical Modeling for English-Chinese Cross-Language Information Retrieval The Effect of Children’s Innovative Education Courses Based on Fractional Differential Equations Fractional Differential Equations in the Standard Construction Model of the Educational Application of the Internet of Things Optimization research on prefabricated concrete frame buildings based on the dynamic equation of eccentric structure and horizontal-torsional coupling Optimization in Mathematics Modeling and Processing of New Type Silicate Glass Ceramics Green building considering image processing technology combined with CFD numerical simulation Research on identifying psychological health problems of college students by logistic regression model based on data mining Abnormal Behavior of Fractional Differential Equations in Processing Computer Big Data Mathematical Modeling Thoughts and Methods Based on Fractional Differential Equations in Teaching 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 Nonlinear Differential Equations in Computer-Aided Modeling of Big Data Technology The Uniqueness of Solutions of Fractional Differential Equations in University Mathematics Teaching Based on the Principle of Compression Mapping Financial customer classification by combined model Influence of displacement ventilation on the distribution of pollutant concentrations in livestock housing Recognition of Electrical Control System of Flexible Manipulator Based on Transfer Function Estimation Method 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 classification of e-commerce customers based on BP neural network The Control Relationship Between the Enterprise's Electrical Equipment and Mechanical Equipment Based on Graph Theory Mathematical Modeling and Forecasting of Economic Variables Based on Linear Regression Statistics Nonlinear Differential Equations in Cross-border E-commerce Controlling Return Rate 3D Mathematical Modeling Technology in Visualized Aerobics Dance Rehearsal System Fractional Differential Equations in Electronic Information Models BIM Engineering Management Oriented to Curve Equation Model 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 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 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 Action of Aut( G ) on the set of maximal subgroups ofp -groupsThe internal mechanism of corporate social responsibility fulfillment affecting debt risk in China: analysis of intermediary transmission effect based on degree of debt concentration and product market competitive advantage Study on transmission characteristics in three kinds of deformed finlines based on edge-based finite element method Asymptotic stability problem of predator–prey system with linear diffusion Research on loyalty prediction of e-commerce customer based on data mining 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 sentiment analysis method based on bidirectional long short-term memory networks A study of local smoothness-informed convolutional neural network models for image inpainting Mathematical Calculus Modeling in Improving the Teaching Performance of Shot Put Application of Nonlinear Differential Equation in Electric Automation Control System Higher Mathematics Teaching Curriculum Model Based on Lagrangian Mathematical Model Computational Algorithm to Solve Two–Body Problem Using Power Series in Geocentric System Decisions of competing supply chain with altruistic retailer under risk aversion Optimization of Color Matching Technology in Cultural Industry by Fractional Differential Equations 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