Secondary Development Technology Research Articles

Hybrid intelligent algorithm and CAD secondary development technology in parameter optimization design of transmission gear set

Hybrid intelligent algorithm and CAD secondary development technology in parameter optimization design of transmission gear set

Research on the Modular Design and Application of Prefabricated Components Based on KBE

The design and production of prefabricated buildings pose challenges in achieving standardization, limiting their extensive adoption. In order to address issues of prefabricated components, such as the low reusability of design knowledge, limited standardization, and design disconnection, this paper adopted the prefabricated cantilevered structure components as the research object. It employs knowledge-based engineering (KBE) theory and secondary split modularization approach in conjunction with Revit secondary development technology to establish a modular design system. The system formalizes complex design knowledge into concise user interfaces and a logically clear programming language, ensuring the design system’s ease of use and accessibility. To validate the authenticity and applicability of the modular design system developed in this paper, a comparison is made between the traditional modeling tool and modular modeling tool. Through empirical analysis, the result indicates that the new tool proposed in this paper can enhance the efficiency of design professionals by 72.92%. Among these, the tool meets the modeling and design requirements of 96.1% of the prefabricated components in the project, making it highly suitable for the modeling and design process of the vast majority of prefabricated components. Therefore, this design approach, which integrates KBE and three-dimensional geometric technology, makes the modular design of prefabricated cantilevered structural components feasible, providing a reference for future research in the design of other prefabricated components.

Construction Safety Risk Assessment and Early Warning of Nearshore Tunnel Based on BIM Technology

The challenging nature of nearshore tunnel construction environments introduces a multitude of potential hazards, consequently escalating the likelihood of incidents such as water influx. Existing construction safety risk management methodologies often depend on subjective experiences, leading to inconsistent reliability in assessment outcomes. The multifaceted nature of construction safety risk factors, their sources, and structures complicate the validation of these assessments, thus compromising their precision. Moreover, risk assessments generally occur pre-construction, leaving on-site personnel incapable of recommending pragmatic mitigation strategies based on real-time safety issues. To address these concerns, this paper introduces a construction safety risk assessment approach for nearshore tunnels based on multi-data fusion. In addressing the issue of temporal effectiveness when the conflict factor K in traditional Dempster–Shafer (DS) evidence theory nears infinity, the confidence Hellinger distance is incorporated for improvement. This is designed to accurately demonstrate the degree of conflict between two evidence chains. Subsequently, an integrated evaluation of construction safety risks for a specific nearshore tunnel in Ningbo is conducted through the calculation of similarity, support degree, and weight factors. Simultaneously, the Revit secondary development technology is utilized to visualize risk monitoring point warnings. The evaluation concludes that monitoring point K7+860 exhibits a level II risk, whereas other monitoring points maintain a normal status.

Research on PTFE/Al reactive jet formation of shaped charge

During the PTFE/Al reactive shaped charge jet formation, the burst wave generated by the explosion of the explosive is sufficient to achieve the ignition conditions of the reactive materials (RMS). As a result, the RMS will react, resulting in an energy loss from the reactive jet. In order to research the forming features of PTFE/Al reactive jet and the energy loss during the jet formation, a PTFE/Al reactive liner with a diameter of 74 mm was prepared and an X-ray pulses photography experiment was performed on the jet formation. And the parameters of Johnson-Cook constitutive model of RMS were obtained through quasi-static experiments and Hopkinson pressure bar experiments. The jet formation were simulated, and the AUTODYN secondary development technology was used. The results show that the secondary development technology can intuitively show the reaction of the active material during the jet formation. The PTFE/Al reactive jet is less cohesive, its jet diameter is thicker, and the morphology is divergent. The reactive materials reacted during the PTFE/Al reactive shaped charge jet formation. And during the reactive jet formation, the inner layer of the liner collided. Therefore, most of the chemical reactions occur inside the reactive jet.

Camera placement optimization for CCTV in rail transit using BIM

In an environment where completely automated lines are gaining popularity, station service employees are declining yearly while passenger volume increases. In many cities, the need for station video surveillance with “complete coverage without dead ends” has been high. The traditional layout scheme based on design experience estimates often results in large blind spots and low efficiency in monitoring. In order to solve this problem, based on BIM technology, this work develops a quantified camera layout optimization approach employing an improved genetic algorithm. The plan includes three modules: the data extraction, which extracts the spatial information of the functional area from the BIM model to generate a data image; the optimization module, which adopts the improved genetic algorithm and uses the pixel coordinates provided by the data image to realize the camera pre-deployment; the visualization module, which designs the simulation plug-in through BIM secondary development technology, simulates and verifies the pre-deployment, and provides the solutions. The approach’s effectiveness was confirmed by verifying the deployment optimization at the station platform level. The optimal solution’s camera coverage is 27.2% better than the experience-based camera layout.

Automatic Generation Construction Shop Design Model of the MEP Hanger Based on BIM

Due to the growing complexity of mechanical, electrical and plumbing (MEP) functions, the design, production and installation of hanger based on MEP has become low efficiency in traditional ways. Compared with the Computer-Aided Design (CAD) approach, the MEP hanger three-dimensional (3D) design approach has not received adequate attention in the process of engineering practice. Based on Building Information Modeling (BIM) and Revit secondary development technology, an automatic generation construction shop design model system of MEP hanger (MEP hanger-CDM) for the quick placement of hanger components, automatic grouping of hanger components and hanger component constructability checking was developed. By conducting investigations with the construction companies and construction sites in China, four basic forms of MEP hanger layouts were identified to accommodate different types of MEP layouts. In addition, the design requirements of the family of LOD 400 BIM models were summarized along with the analysis of user requirements. The results of the case studies indicate a 70% reduction in the manpower number on the MEP hanger shop design and an 85.9% reduction in the number of working hours. Moreover, the efficiency of the hanger construction model design and the accuracy of the output of material lists and shop drawings could be improved. Thus, the process of designing MEP hanger could be optimized in a visualized method.

Research on Coal Mine Building Compliance Inspection System Based on Accident Causation and BIM in China

Coal mine construction projects have high risks, and non-compliant designs generated in the design stage will have adverse effects on subsequent construction and production stages. Therefore, it is of great importance to conduct effective preconstruction compliance inspections on coal mine construction designs. To make the compliance check of coal mine building design more rapid and effective, and to reduce the risks arising from the design phase, this study built a compliance inspection system for coal mine building design from the causes of coal mine accidents, using the Word2Vec word similarity calculation method and BIM platform secondary development technology. The system was tested and was found to be able to detect a 92.82% non-compliant component rate where the correct inspection rate was 97.68%. In addition, the inspection time for a single component was only 0.23 s. The construction of the compliance inspection system based on accident causes has changed the extensive inspection mode in the traditional manual model inspection, and the inspection no longer depends on the experience of inspectors, thus improving the efficiency and accuracy of coal mine building model inspection. The inspection focuses on the building elements with high risks, which achieves the purpose of risk control in the design stage.

The Effect of Aluminum Particle Size on the Formation of Reactive Jet

In order to study the morphology characteristics of the PTFE/Al reactive shaped charge jet and the chemical reaction during the jet formation, PTFE/Al reactive liners with aluminum particle sizes of 5 μm and 100 μm were prepared. The parameters of the Johnson–Cook constitutive model of PTFE/Al reactive materials (RMs) were obtained through quasi-static compression experiments and SHPB (Split Hopkinson Pressure Bar) experiments. X-ray imaging technology was used to photograph the shape of reactive shaped charges jet at two different time points. The AUTODYN secondary development technology was used to simulate the jet formation, and the simulation results are compared with the experimental results. The results show that the simulation results are close to the experimental results, and the error is in the range of 4–8%. Through analysis, it is observed that the RMs reacted during the PTFE/Al reactive shaped charge jet formation, and due to the convergence of the inner layer of the liner during the jet formation, the chemical reaction of the jet is from inside to outside. Secondly, the particle size of aluminum powder has an influence on the chemical reaction and morphology of the jet. During the jet formation, there were fewer RMs reacted when the PTFE/Al reactive liners were prepared with 100 μm aluminum powder. Compared with 5 μm aluminum powder, when the aluminum powder is 100 μm, the morphology of the jet is more condensed, which is conducive to generating greater penetration depth.

Thermo-mechanical coupling simulation of PBX explosive charge in launch environment

The distribution of internal stress and temperature of explosive charge in launch environment is significant to determine the launch safety of explosive charge. PBX is composed of energetic particles, binder and metal powder, hence it can perform the viscoelastic mechanical properties under the external force loading condition. The generalized Maxwell constitutive equation is embedded into LS-DYNA program by secondary development technology, and verified rational after the simulation of launch safety experiment of explosive charge. Utilizing the constitutive equation and considering the influence of viscoelastic work and chemical reaction heat, the distribution of internal stress and temperature of explosive charge in launch environment is acquired. The results indicate that the viscoelastic work and chemical reaction heat produce a 4K highest temperature rise of explosive charge, the explosive charge without defects cannot ignite in the launch process. The results provide a certain guiding significance for the launch safety evaluation of explosive charge.

Numerical research on ablation and wear of the artillery barrel based on UMESHMOTION user‐defined subroutine

AbstractDuring the firing process, the gun barrel bears the thermal and chemical erosion of high‐temperature gunpowder gas and the wear of the rotation band. The forced cone tended to the most severely worn part of the barrel, which directly affects the life of the barrel. Combined with the erosion test and wear test of gun steel materials, this research studied the forcing cone of a medium caliber naval gun barrel. With the commercial finite element software ABAQUS as the platform, we took advanced adaptive mesh method combined with secondary development technology. This method used in our study in order to better realize the numerical simulation of the radial erosion wear of the forced projectile cone in the continuous firing environment. At the same time, we compared the numerical simulation with the actual firing test data, and proposed a new calculation method of barrel life. In conclusion, the results of this study showed that this method can better calculate the radial erosion wear of the forced cone, and provide guidance for improving the life of the gun barrel in the future.

A test method for launch safety of explosive charge accurately simulating launch overload

ABSTRACT In this paper, the generalized Maxwell constitutive equation is embedded into LS-DYNA program by secondary development technology, the projectile launching process is numerically calculated, and the stress distribution of explosive charge in the launching process is described. According to the calculation results, the explosive charge launch safety simulator for the research of explosive charge launch safety is designed and developed. Then the experiment is carried out, and the dynamic behavior and ignition process of explosive charge were obtained. Finally, a quantitative evaluation method for the launch safety of explosive charge is established, and the launch safety of the PBX is evaluated.

Statistical System of Cultural Heritage Tourism Information Based on Image Feature Extraction Technology

This paper presents an in-depth study of a statistical system using image feature extraction technology for cultural heritage tourism information. Based on the specificity of the tourism industry, it combines the technical architecture, framework of image feature extraction, GIS basic design, database design, and other related theories; realizes visual mapping through relevant tourism statistics in GIS; and uses the spatial analysis capability of ArcGIS software to complete the statistical scheme of cultural heritage tourism information data in the context of Internet big data. In this paper, the image preprocessing process is accelerated by the parallel optimization of the filtering operation and down-sampling operation in the relevant image preprocessing algorithm. The preprocessed images can effectively improve the recognition effect of the image feature extraction and classification stage. Based on cultural heritage tourism information mining results, the design and development of the tourism information statistics platform are carried out. The platform is built and developed using GIS secondary development technology and HTML + CSS front-end development technology API, Echarts, and other image feature components. The platform enables the massive and disorganized tourism text information to be displayed in a way that is easier to understand in both maps and text. This paper’s research on critical technologies provides technical support for image feature extraction of tourism statistics, which has specific practical value. Implementing the cultural heritage tourism platform offers a visual operating environment for tourism, enabling cultural heritage tourism businesses to tap into user preferences so that users can effectively access the travel options that interest them, which is conducive to promoting the development of travel recommendation platforms.

Design of In-Depth Multi-intelligence Teaching System under the Mixed English Teaching Mode

After the implementation of the hybrid network-based English teaching system, a wide-ranging trial was carried out in schools. Although the trial time was not very long, according to the feedback given by the students, it is not difficult for us to find that the practicability of the English network teaching system is very strong, which is very suitable for current college students. The main goals of this research are the application development of the open source Moodle course management system and the practical design and realization of the English network teaching system based on in-depth research on the Moodle system and the secondary development technology. In view of the development of the existing English online teaching system in China and the current situation of domestic audio-visual information construction, it is planned that Moodle, an open source and free software system that fully complies with the CPL and GPL protocols, is used to teach the English language through in-depth research on the software support system. The software bottom layer supports the network teaching system and then uses PHP and web technology to expand and integrate system functions according to different needs and finally realize an English network teaching system suitable for college students at this stage.

Parametric Optimisation Analysis of Micro/Nano-Satellite Flywheels Based on the NSGA-Ⅱ Optimisation Algorithm

As the key mechanism of attitude control of micro/nano-satellites, the flywheel design is mostly based on empirical formulae that do not meet the requirements of lightweight and high-performance micro/nano-satellite platforms. In this paper, the structural shape of micro/nano-satellite flywheels is analysed, and a set of flywheel optimisation methods is proposed to realise the parametric optimisation analysis of the structural shape. First, the general principle of flywheel efficiency is introduced, the optimisation evaluation factor of flywheel design is proposed, and the parametric model of a flywheel structure is established by using the finite element secondary development technology, which can be used to quickly build a finite element model of different dimensions. Second, the optimisation model of flywheels is established while introducing the approximate model algorithm, greatly improving the optimisation efficiency. Considering the phenomenon that the genetic algorithm falls below local optimisation under a large parameter range, the method of initial optimisation is proposed to reduce the upper and lower limits of the optimisation parameters. Finally, the optimal shape of the flywheel is obtained by using the parametric optimisation model of the flywheel. The finite element analysis results show that the flywheel optimisation evaluation factor proposed in this work can effectively improve the comprehensive performance of the flywheel as the optimisation target, and the corresponding optimisation method can be well applied to the engineering application and design of micro/nano-satellite platforms. This can help guide the structural optimisation design of micro/nano-satellite platforms in the future.

A Quantitative Method for Determining Underground Garage Parking Comfort and Development of a BIM Based Analysis Program

The current parking space design only considers whether the parking space size meets the requirements of the specification, but because of people’s parking habits, parking technology is different and its requirements for parking comfort are different, and so our parking space design should be people-oriented to meet people’s requirements for parking comfort. At present, the main dilemma faced by designers considering the comfort of parking is that it is difficult to quantify the comfort of parking. At the same time, the number of parking spaces in underground garages is large, so manual calculation of the comfort of parking is a huge task. Therefore, in this paper, we put forward the concept of parking comfort and put forward a calculation model that can quantify the parking comfort. Considering the position coordinates of the collision-prone parts in the whole process of vehicle parking, the collision position coordinates and site obstacle coordinates are established together to form the vehicle collision constraint relationship in the process of parking, so as to quantify parking comfort into specific values. At the same time, based on the calculation model and BIM secondary development technology, we develop a program for automatic calculation and detection of parking comfort based on the BIM model, so as to automatically evaluate the parking comfort of each parking space in the whole underground garage effectively, quickly, and accurately.

Two-level quantitative risk analysis of submarine pipelines from dropped objects considering pipe–soil interaction

Pipeline damage from platform dropped objects is a significant risk for offshore installations. Pipelines are usually buried to reduce the risk. Previous methodologies and standards haven't addressed the nonlinearity and pipe–soil interaction in risk analysis. Moreover, the appropriate burial depth remains undetermined, causing unnecessary investment or potential risk. To provide a comprehensive evaluation, this study presents a two-level quantitative risk analysis for pipeline failure. Finite element analysis and probabilistic approaches are coupled to quantify the effects of nonlinearity and pipe–soil interactions and the underlying uncertainties of related factors. At the macro-level, a frequency-consequence procedure is developed to assess the spatial distributions of pipeline failure probabilities, which are then utilised in the preselection of pipeline routes and post-design risk assessment. At the micro-level, based on a secondary development technology, a reliability-based framework is proposed and verified, providing insights into the failure mechanisms of each collision event and investigate the variabilities of related parameters. These methodologies can be used as guidelines for pipeline risk analysis and protection, avoiding excessive conservatism by considering pipe–soil interactions (seabed flexibility and burial depth). The relationships between protection measures and failure probabilities are established to provide clues for the selection of optimal burial depth.

Research on the Intelligent Construction of the Rebar Project Based on BIM

Rebar engineering in the construction industry lacks effective technical means and has a high processing cost and high waste rate. Under the background of intelligent construction, the centralized processing mode of steel bars in prefabricated factories realizes the automatic processing of steel bars and improves the processing efficiency of steel bars. Using the C# programming language, combined with Revit secondary development technology, the automatic generation of the rebar model and the automatic export of rebar drawing are realized, which saves time for the designers to build the model. The calculation method of the cutting length of the steel bar is analyzed in this paper, which can be used as a reference for the subsequent optimization research of steel bar cutting. The assembly position information of the steel bar was introduced into an Excel table to help realize the automatic assembly of the steel bar cage and the intelligent construction of the steel bar. Combined with mixed reality technology, project personnel can interact with the reinforced BIM model through the mixed reality device Hololens2 to guide construction remotely.

Frost heave and thawing settlement of the ground after using a freeze-sealing pipe-roof method in the construction of the Gongbei Tunnel

The port section of the Gongbei Tunnel of the Hong Kong Zhuhai Macao Bridge is constructed by the freeze-sealing pipe-roof method, a new construction method that combines the pipe-roof and artificial ground freezing techniques. If the frost heave and thaw settlement of the ground are not effectively predicted and controlled during tunnel construction, then the surrounding environment of the tunnel will be adversely affected. In this study, thermophysical and mechanical parameters such as frost heave ratio and thawing settlement coefficient are obtained by the laboratory test of frozen-thawed soil. Then, the frost heave and thawing settlement laws of the ground are simulated by the full-coupled analysis method of transient temperature and displacement according to the secondary development technology of the ABAQUS finite element software considering the orthotropic deformation characteristics of frozen soil during the construction of the Gongbei Tunnel. The numerical simulation results show that the maximum vertical frost heave displacement of the stratum is 164.47 mm and the maximum horizontal frost heave displacement of the stratum is 53.80 mm, while the maximum vertical thawing settlement displacement of the stratum is −69.45 mm and the maximum horizontal thawing settlement displacement the stratum is −43.89 mm. Moreover, the error of the maximum vertical frost heave displacement between numerical simulation and field measurement is only 5.89 mm, which shows that the numerical simulation method proposed in this paper has high prediction accuracy.

Development of visual helicopter emergency rescue system

Abstract Helicopter rescue is an important part of emergency rescue syste m, an d is oft en ca r r ie d out under complex terrain and low-visibility meteorological conditions. In order to ensure the safety of helicopter flight and the timely and efficient implementation of emergency rescue, it is necessary to establish a visual emergency rescue system. This paper selects Chongqing as the reference city, and it is preliminarily planned to take “GeoSim” as the 3D simulation platform, combined with the secondary development technology of geographic information system (GIS). According to the current flight performance of helicopters, and through the analysis of obstacle crossing, the intelligent algorithm can realize the visual simulation demonstration of single helicopter rescue system and multi-helicopter rescue system along the optimized path and user-defined path, and give the quality evaluation of emergency rescue drills, as well as the suggestions of the best emergency rescue plan.

AUTOMATIC IDENTIFICATION AND QUANTIFICATION OF SAFETY RISKS EMBEDDED IN DESIGN STAGE: A BIM-ENHANCED APPROACH

Design stage plays a decisive role in safety risk management of the whole life cycle for construction projects. However, existing research mostly pay attention to post-accident management and lack pre-management consciousness. Based on the concept of design for safety (DFS), this paper explains how design optimization can enhance the safety performance for construction projects. Firstly, use accident causality theory and trajectory crossing theory to clarify the logical relationship between safety accidents and design process. Then, identify risk sources of safety accidents in deep foundation pit of subway projects and form a safety management knowledge base. Thirdly, based on design and review rules in the knowledge base and improved FEC risk quantification method, quantify the design oriented subway construction safety risks. Finally, use BIM secondary development technology to realize automatic examination and visualization of safety risks. A case study was conducted to verify this research framework. This paper can be a supplement to the existing risk management theoretical research.