Welcome to Journal of Graphics share: 
Bimonthly, Started in 1980
Administrated: China Association for  Science and Technology
Sponsored: China Graphics Society
Edited and Published: Editorial Board  of Journal of Graphics
Chief Editor: Guoping Wang
Editorial Director: Xiaohong Hou
ISSN 2095-302X
CN 10-1034/T
Current Issue
30 April 2024, Volume 45 Issue 2 Previous Issue   
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Cover of issue 2, 2024
2024, 45(2): 1. 
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Table of Contents for Issue 2, 2024
2024, 45(2): 2. 
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Digital Design and Manufacture Special
Application and prospect of digital twin in the design, manufacturing, and operation of aerospace structures
HUANG Wenkai, LIANG Zhihong, WANG Minghua, ZHANG Wenfeng, WANG Yishou
2024, 45(2): 241-249.  DOI: 10.11996/JG.j.2095-302X.2024020241
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The application of digital twin technology in the aerospace field is an important development trend at present and in the future. In a virtual-real way, the digital twin simulates the behavior and performance evolution of aerospace structures under different working conditions. The digital twin technology can provide comprehensive support for structural optimization design, high-efficiency manufacturing, and low-cost maintenance of aerospace equipment. This paper reviews the application status of digital twins in the whole life cycle management of aerospace structures, and summarizes the problems, challenges, and development trends of digital twins in aerospace structures.

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Peg-in-hole compliant assembly method based on skill learning of force-position perception
LU Longfei, WANG Junfeng, ZHAO Shiwen, LI Guang, DING Xintao
2024, 45(2): 250-258.  DOI: 10.11996/JG.j.2095-302X.2024020250
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Traditional methods for robot peg-in-hole assembly face challenges in constructing accurate geometric contact models and learning methods that require large samples with a high initial attitude deviation leading to a low assembly success rate. A compliant robot peg-in-hole assembly method was proposed based on the skill learning of force-position perception. During the hole search stage, the force and torque sample data for the peg missing the hole were uniformly collected, constructing a force-action dataset. A multi-layer perceptron and an attention module network were constructed for supervised learning, generating a discriminant model for mapping force to action. Based on the six-dimensional force signal in the assembly process, the method predicted the next assembly action, while reducing both the angle and distance between the peg center line and hole center line to achieve proper alignment of the peg and the hole. During the hole insertion stage, a compliance control algorithm was designed with position control as its inner loop. By setting desired contact forces on the end face of the peg, real-time adjustments were made to both the position and orientation of peg parts using active compliance techniques based on feedback from a six-dimensional force sensor. To validate its effectiveness, 100 sets of assembly experiments were conducted using a single axle hole with a minimum clearance of 0.1 mm. The method achieved an average success rate of 94% within an average time of 15.1 seconds. Comparative analysis with other assembly algorithms demonstrated that the force-position perception assembly method based on skill learning significantly enhanced efficiency and success rate in peg-in-hole assemblies.

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Space gravitational wave detection parameter management and performance analysis based on MBSE
ZHU Yiming, ZHANG Yuzhu, CHEN Bin, PENG Xiaodong, GAO Chen, LIU Yu, TANG Wenlin, QIANG Li’e, XU Peng, LUO Ziren
2024, 45(2): 259-267.  DOI: 10.11996/JG.j.2095-302X.2024020259
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In order to dynamically associate the decomposition of top-level parameters with the analysis of system-level performance in the space gravitational wave detection system, and to provide management and application analysis capabilities for the entire lifecycle information of space science tasks, a model-based system engineering (MBSE) method for managing parameters and analyzing detection performance in space gravitational wave detection systems was proposed. Parameter models for space gravitational wave detectors were constructed using the system modeling language (SysML), enabling the analysis of model content and recording of parameters after screening. Finally, an analysis was conducted on the detection performance of the space gravitational wave detection system for different scientific targets through detection sensitivity, which served as the main criterion for evaluating the detection ability of the system. The results demonstrated that the proposed method can enable the uniform management and tracing of all parameter contents, thereby supporting the demonstration of top-level parameters and the evaluation of system-level performance in the space gravitational wave detection system.

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Conceptual design of surface-to-air missile based on MBSE
SU Hu, FANG Shizhe, TIAN Kunxiao, GONG Chunlin
2024, 45(2): 268-276.  DOI: 10.11996/JG.j.2095-302X.2024020268
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To accommodate future demands for large-scale complex system design and functional analysis, the concept of model-based systems engineering (MBSE) was introduced in missile design, and an MBSE-based conceptual design process for surface-to-air missiles was proposed. Firstly, stakeholder requirements for surface-to-air missiles were clarified, and missile mission scenarios were defined. Functional analysis was then conducted based on design requirements, utilizing missile mission scenarios for functional decomposition, and completing the transformation from requirements to functions. Based on the system functions of the missile, the missile’s architecture composition was mapped, and the logical and physical architecture design of the surface-to-air missile system was carried out. Finally, the conceptual design scheme for the missile was formulated, and verification and optimization were performed for the missile scheme, thereby preliminarily achieving the conceptual design process for surface-to-air missiles.

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Function design method and application of civil aircraft system based on SysML
YAN Jianing, ZHANG An, HUANG Zhanjun, WANG Yiming
2024, 45(2): 277-283.  DOI: 10.11996/JG.j.2095-302X.2024020277
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In response to the lack of formal description, weak model reusability, and insufficient establishment of dynamic models in the current civil aircraft system function design process, the concept of model-based systems engineering (MBSE) was introduced into the civil aircraft systems design process, and a set of methods for civil aircraft system function design based on the systems modeling language (SysML) was proposed. Firstly, the methods defined the use case model, abstracted the top-level functional vision of the system, and then carried out the decomposition and allocation of functions and the construction of the static function models for the system. Next, it established a function flow model of the system, and then divided the function swim lanes and constructed function interaction sequences, aiming to analyze the behavioral characteristics of the system from multiple perspectives. During this process, dynamic function models of the system were constructed by combining activity diagram, swimlane diagram, and sequence diagram. Finally, it provided the implementation of the system’s structural interface, forming a set of comprehensive function design methods with strong logic. Taking the civil aircraft avionics system as an example for function design, function models of the avionics system were established using the SysML verifying the feasibility and effectiveness of the proposed method, which was applicable to the function design of civil aircraft systems.

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Research on scenario-oriented radar system model design and simulation
ZHANG Ran, LI Yuan, WANG Hao, SUN Zhaoqiang, ZHAO Yuanyuan
2024, 45(2): 284-291.  DOI: 10.11996/JG.j.2095-302X.2024020284
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Because the working process and interface interactions of radar systems are currently mainly described in the text form, the overall verification of the system has become overly reliant on physical objects, leading to issues such as long verification cycles and high design correction costs. In view of the problems existing in the development process, this paper adopted the idea of MBSE to carry out radar operation scenario-oriented demand analysis. According to the maturity and complexity of the radar system function, it elaborated on the functional analysis methods suitable for different radars, and emphasized the radar system and subsystem architecture design and three-level simulation verification method. By advancing part of the verification link in the system debugging stage to the initial stage of system design, the paper solved the pain point problem of over-dependence on physical objects, which held significant implications for the application of a new development mode for radar systems.

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Research on modeling method of top-level function decomposition and allocation for aviation power equipment
HE Wenhu, LIU Wei, WANG Youlong, CAI Hui
2024, 45(2): 292-299.  DOI: 10.11996/JG.j.2095-302X.2024020292
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Focused on the problems of top-level functional decomposition and allocation for aviation power equipment, such as overly reliance on experience, unreasonable division of functional interfaces, and unclear functional undertaking of subsystems, this paper proposed a model-based functional analysis method for aviation power equipment by studying the characteristics and advantages of MBSE modeling method, system modeling language (SysML) and by integrating behavior diagram, structure diagram, and matrix view into the functional design activities. Firstly, the system boundary and interaction information of aviation power equipment were identified through modeling of environment background diagram. Secondly, the top-level functions of the system were analyzed through use case diagram. Each top-level function was analyzed through modeling by automatically generating associated activity diagrams from the use case. The initial decomposition of functions was realized through conceptual scheme demonstration, and iterated with system architecture modeling and functional hazard assessment (FHA) to complete the detailed decomposition. Finally, the function list of subsystems was obtained through allocation matrices and allocation views, serving as the input for subsystem function analysis. The research demonstrated that the model-based method could effectively address the problem of unclear functional decomposition and allocation in the field of aviation power equipment. The typical cases of constructed functional model could provide a technical path for the subsequent construction of aviation power equipment digital prototypes 1.0.

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Research on knowledge graph-based aviation multi-modal data organization and discovery method
HE Liu, AN Ran, LIU Shuyan, LI Runqi, TAO Jian, ZENG Zhaoyang
2024, 45(2): 300-307.  DOI: 10.11996/JG.j.2095-302X.2024020300
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The data generated in the life cycle of aviation products shows the characteristics of multi-source and multi-modal. When constructing knowledge engineering for such data, the traditional text retrieval method based on keywords has become inadequate to meet the needs of researchers for knowledge acquisition in the process of scientific research. As a current method for knowledge representation in the specific domain of artificial intelligence, knowledge graph provides an adequate expression and standardized storage of the systematic and relational aspects between knowledge units and data. It served as an effective means of organizing domain-specific data and facilitating knowledge discovery services. Therefore, to reconstruct the operational thinking of researchers, it was proposed to use the knowledge graph as the knowledge expression model in the aviation domain, employing the standard knowledge unit as data carriers. Furthermore, the deep neural network was utilized as the feature encoder of multi-modal data, generating feature vectors for machine understanding and computation. By combining these two key technologies, a search and recommendation engine was built for multi-modal data. Building upon this technological foundation, a system architecture was designed and a knowledge discovery platform was implemented. This platform organized and indexed multi-modal data at the knowledge level, meeting the multi-modal knowledge retrieval needs of aviation researchers.

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Automated testing study for civil aircraft requirements’ verification
WANG Hao, WU Zhongzhi, TANG Jian
2024, 45(2): 308-316.  DOI: 10.11996/JG.j.2095-302X.2024020308
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Requirement and concept demonstration is the early stage of the development lifecycle of commercial aircraft, which will significantly impact the whole life cycle cost. Functional definition describes a series of standardized and unified expected behaviors of the targeted product and can be regarded as one of the core products in the requirements and concept demonstration stage. Functional requirements, as key outputs of the functional definition process, determine the core product competitiveness of commercial aircraft. As a common means for evaluating requirement quality, function simulation-based requirement verification is employed to establish a test model of an aircraft and to simulate its behavior in specific scenarios, thus confirming whether the early-stage design specifications meet the requirements based on the simulated results. However, in the actual requirement-oriented simulation process, the variability of external environmental factors in specific scenarios often leads to test cases exhibiting what is commonly known as “combinatorial explosion”, significantly increasing the scale and cost of testing. In order to solve the problem above, a model-based testing (MBT) methodology was proposed. It will automatically generate test cases based on system modeling language (SysML) models, thereby shortening the verification cycle and ensuring the traceability of requirement verification.

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Design and modeling method of IPIS system for subway trains
HUANG Tingli, WANG Baomin, WANG Haifang, ZHAO Jiahao, ZHOU Lujie, GUAN Lin
2024, 45(2): 317-324.  DOI: 10.11996/JG.j.2095-302X.2024020317
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In response to the challenges faced by the text-based system engineering (TBSE) approach in designing passenger information systems (PIS) for subway trains, including low design integration, low development efficiency, weak inter-function connectivity, and poor traceability, this paper proposed a modular approach for the three primary functions of PIS, introducing the intelligent passenger information system (IPIS). Combining this with model-based systems engineering (MBSE) methods, the system was designed and modeled. The IPIS system’s design and modeling method was presented, transitioning from black-box to white-box. This process encompassed eight stages, including stakeholder analysis, stakeholder requirements analysis, use case and use case scenario analysis, black-box activity analysis, white-box activity analysis, functional analysis, system requirements analysis, and system architecture design. system modeling language (SysML) was utilized to construct the IPIS system’s functional element model, enhancing model reusability. The effectiveness and feasibility of the proposed approach were validated through a practical IPIS system design example.

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Research on the architecture and model construction method of electromagnetic domain parallel system
YU Xiang, ZOU Benzhen
2024, 45(2): 325-331.  DOI: 10.11996/JG.j.2095-302X.2024020325
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In order to study the architecture and model construction of electromagnetic domain parallel system, the concept of digital parallelism was analyzed. It was proposed that there exists a mutually driven, symbiotic, and equal bidirectional evolution relationship between digital parallel system and physical system. Based on the four key points regarding the ability of parallel system to generalize and simulate physical system, as well as the methodology of size parallel closed loops, a typical LVC (constructed, virtual, and real) architecture was proposed. Based on the definition and classification of model systems, the transmission logic and construction methods of models were provided from the aspects of model commonality, individuality boundaries, and cross level simulation model validation. Taking the construction of a parallel simulation environment and the modeling of navigation interference under adaptive zero adjustment as an example, the feasibility of the proposed parallel system architecture and model construction method in this paper was analyzed. This study aims to provide a clearer and more accurate analysis of the concept and boundaries of parallel system. On this basis, a theoretical construction method for electromagnetic domain parallel system was proposed, thus providing reference for the specific implementation of similar parallel system and model constructions in the future.

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Research on spacecraft mechanisms production line balance based on digital twin technology
PANG Bo, YANG Hui, YU Rongrong, ZHANG Haoyue, LUO Qiang
2024, 45(2): 332-338.  DOI: 10.11996/JG.j.2095-302X.2024020332
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With the development of China’s aerospace, the increasing number of spacecrafts launches, and the rising demand for shape memory alloy hold-down and release mechanisms for spacecrafts, it is urgent to establish a digital and intelligent production line tailored to the production characteristics of spacecraft products. In this paper, according to the production characteristics of spacecraft shape memory alloy hold-down and release mechanisms, three digital twin models were proposed: the product digital twin model, equipment digital twin model and manufacturing process digital twin model in the manufacturing process of spacecraft mechanisms. The functional module of the digital twin workshop was designed, and a process balancing method of the production line based on industrial engineering (IE) and genetic algorithms was proposed. Furthermore, an information integration and application prototype system based on the digital twin was developed, along with the development of digital twin service interfaces and human-machine interfaces. An automated, digital, and intelligent production line has been established, achieving the information integration and application of digital twins of spacecraft mechanisms, equipment and processes. This has enabled synchronous operation and real-time interaction between virtual and real workshops, significantly boosting the production capacity of spacecraft shape memory alloy hold-down and release mechanisms.

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A DoDAF-based method for developing MBSE for EMU
WANG Haifang, ZHANG Lei, LIU Huijun, LU Yiming, SUN Minghui
2024, 45(2): 339-346.  DOI: 10.11996/JG.j.2095-302X.2024020339
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The innovative process of electric multiple units (EMU) design necessitates a comprehensive consideration of various factors, including the adaptation to diverse operational scenarios such as high-speed travel and ground mobility. This design process involves analyzing factors such as operating environments, conditions, overhead catenary systems and signal transmission, and to construct a system-level framework for structural modeling based on the on the capability of EMU. Drawing from the framework of the united states department of defense architecture framework (DoDAF), and employing methods of scenario modeling and requirements capture, combined with a customized view description language UPDM tailored to the DoDAF modeling framework, results in an architecture-based design idea. Enhanced structural design through enhancements to the UPDM language such as block diagrams and activity diagrams. In this paper, we take the “departure scenario” of EMU as an example, describe its operation process comprehensively, and integrate requirements analysis, functional decomposition and system integration to construct a system engineering development methodology with behavior-driven functions as the core.

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Modeling and implementation of EMU traction system based on top down design
WANG Haifang, ZHANG Lei, WANG Xin, SUN Minghui, XUE Lianmin
2024, 45(2): 347-354.  DOI: 10.11996/JG.j.2095-302X.2024020347
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With the increasing complexity of rail transit products and the development of intelligent level, the design of electric multiple units (EMU) traction systems demands more effective requirement analysis methods, more reliable modeling analysis methods, positive traceability design methods, and high-quality implementation forms. Taking the traction system of EMU as the research object, this study utilized the requirements analysis model based on system modeling language (SysML) language and combined it with a modeling analysis method based on the standard requirement-function-logical-physical (RFLP). Starting from the design requirements of the traction system, a complete use case analysis was carried out, leading to the creation of a functional model of the traction system, including both the architecture model and the state machine model. The interactive information between the traction system, external system, and internal subsystems was displayed through block definition diagram and internal block diagram. The operation scenarios of the traction system were realized through UI interfaces, and the state changes of the traction system during operation were displayed. Functional logic simulation of the traction system was realized, and a positive traceable design and implementation scheme of the traction system was formed. The design method based on model-based systems engineering (MBSE) was applied to the design process of EMU, thereby providing forward design guidance for the design of EMU.

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Modeling method for design of diesel engine system based on MBSE
MA Yanli, ZHANG Jizhong, HAO Jibin, LIANG Wei, LI Xiuchun
2024, 45(2): 355-362.  DOI: 10.11996/JG.j.2095-302X.2024020355
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With increasing demands for power systems in national defense weapons and equipment, the complexity of diesel engine systems has increased sharply. Traditional document-based system engineering methods can no longer effectively meet the efficient, accurate, and reliable development requirements of diesel engines. Therefore, model-based system engineering (MBSE) methods have been introduced into the diesel engine development process. This paper proposed a diesel engine system modeling process based on requirements-function-logical-physical (RFLP) and MBSE, as well as a diesel engine model system supporting the operation of this process. Based on this, the paper utilized a diesel engine development task as an example, and took the model as the core, providing the MBSE system modeling process and its model examples. The modeling of diesel engine requirements analysis, diesel engine function modeling, and diesel engine system architecture analysis and synthesis were elaborated. This demonstrated the advantages of the model-based design method in early verification of requirements, rapid simulation of functions, and data traceability in the diesel engine development process, thereby effectively enhancing R&D design efficiency.

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Research on UAV autonomous positioning system for system engineering
LU Yuanjie, CHEN Xingyi, SU Dalin, SUN Wei
2024, 45(2): 363-368.  DOI: 10.11996/JG.j.2095-302X.2024020363
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System engineering is a bridge connecting various engineering disciplines. It aims to optimize each subsystem to obtain better system behavior ability when designing and implementing complex systems. It plays an important guiding role in the design and development of UAV systems. Among the many subsystems of the UAV system, the positioning system provides accurate location information for the UAV, which is the basis for subsequent navigation and obstacle avoidance functions. This paper designed an autonomous positioning system for UAV system engineering, including multi-sensor system modeling, front-end visual inertial odometry, tightly coupled back-end optimization algorithm, system positioning results and environment map output, thus realizing UAV autonomous positioning in complex environments. An experimental verification platform was designed to verify the accuracy and robustness of the positioning system. The experimental results showed that the average positioning error of the proposed UAV autonomous positioning system was less than 0.07 m, which met the requirements of UAV system engineering design.

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Model based virtual and real integration technology for multi-machine collaborative validation testing
WANG Yanhui, LU Yuanjie, YI Wenqing, YU Tao, WAN Xu
2024, 45(2): 369-373.  DOI: 10.11996/JG.j.2095-302X.2024020369
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Given the characteristics of multi-machine combined operation and virtual-reality integration in multi-machine collaborative validation testing in a ground test environment, this paper presented a model-based virtual and real integration technology for multi-machine collaborative validation testing. The environmental architecture design was verified using the virtual and real integration technology. The semi-physical aircraft (airborne equipment and, a small number of auxiliary simulation models), the core aircraft (airborne computer type equipment and, supplementary simulation models), and the digital aircraft (mission systems and flight simulation models) served as the verification object. By employing the methods of “model in the loop” and “supplementing reality with the virtual,” utilizing the validation testing acceptance process, combining the virtual-real interface adaptation technology, difficulties encountered in conducting comprehensive system testing due to missing or imperfect functions of onboard equipment or systems were overcome, and issues such as the inability of the traditional interface-level simulations to meet the time sequence and function logic requirements of comprehensive system testing were addressed. This facilitated rapid simulation iteration validation throughout the entire process, enabling early identification of emergent properties in the system, providing decision criteria for system design quality, supporting rapid iteration optimization of system design, and reducing development cycle and costs.

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Research on rule-based method for automatic generation of SysML use cases
LIU Meng, GENG Shizhan, DING Guohui
2024, 45(2): 374-382.  DOI: 10.11996/JG.j.2095-302X.2024020374
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Modern systems have become increasingly complex, and traditional engineering methods often struggle to handle these complex problems. Model-based systems engineering (MBSE) could rapidly and accurately grasp system behavior and performance by constructing system models, analyzing and simulating systems, thus effectively addressing complexity problems. The systems modeling language (SysML) can aid in clear understanding and description of systems. Previously, natural language-based system description methods were prone to misunderstandings and inaccurate expression issues. Therefore, SysML diagram automatic generation based on NLP technology is currently a research area with great academic value, but current research in this area is relatively limited. This study proposed a method named natural language-driven use case diagram automatic generation, abbreviated as NLUCD. Firstly, it employed pre-determined language rules to preprocess input text. Then it applied NLP tools for text segmentation, stemming, and lemmatization. Next, it utilized a fine-tuned BERT (bidirectional encoder representations from transformers) model for named entity recognition and syntax dependency analysis. Subsequently, it defined three sets of rules to extract participants, use cases, and relationships in the use case diagram, corresponding to the elements and relationships in the use case diagram. Finally, the drawing tool completed the generation of the SysML use case diagram. Although the proposed method is currently mainly applicable to English text, it provides new ideas and perspectives for the automation and intelligence of the system design field, having both theoretical and practical value.

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System interface design of civil aircraft based on system engineering and the control method research
ZHANG Zhao, TANG Jian, WANG Hao, WANG Shiyuan
2024, 45(2): 383-387.  DOI: 10.11996/JG.j.2095-302X.2024020383
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The interface of civil aircraft systems should meet the requirements of functionality, performance and physical space. The design and control of system interfaces is one of the most important tasks in the design of civil aircraft airborne systems, subsystems, and equipment. Based on the concept of system engineering, taking the relevant requirements of interface definition and design of airborne system, subsystem and equipment as input, combined with the definition of airborne system development stage, this study proposes a hierarchical interface definition and design method based on interface design requirements, and a control strategy for interfaces at the same level and between the upper and lower levels. Combined with a civil atmospheric data subsystem, this study took the design and control of electrical interfaces as a typical case, and introduced the specific practices of interface design and control, thereby providing a practical reference for the design and control of various interfaces of civil aircraft airborne systems, subsystems, and equipment.

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Dynamic estimation of heat source distribution during solidification of composite materials under sparse monitoring samples
WANG Shixin, XU Ke
2024, 45(2): 388-398.  DOI: 10.11996/JG.j.2095-302X.2024020388
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Carbon fiber reinforced polymer (CFRP) has excellent properties and has become the material of choice for reducing weight and enhancing efficiency in high-end aerospace equipment. Curing is a critical process in achieving the forming and load-bearing of a composite member. The temperature field of the component in the curing process directly determines the curing quality and mechanical properties of the component. Accurately and dynamically reversing the heat source distribution on the surface of the composite member is the key to realizing the accurate control of the temperature field. However, in the actual curing process, auxiliary materials such as breathable felt and vacuum bags are attached to the surface of the composite, making it difficult to directly monitor the surface temperature field. Only several optical fiber temperature measurement points can be introduced to obtain sparse temperature samples, posing challenges to the reconstruction of the high-dimensional scalar field of heat source distribution. Therefore, a dynamic estimation method of heat source distribution in the curing process based on Gaussian mixture distribution model (GMM) was proposed, which introduced the physical a priori equivalence of Gaussian fuzzy and in-plane heat diffusion, established a Gaussian fuzzy-based temperature field evolution model, and then use multiple Gaussian distributions in the GMM to characterize heat source distribution in the curing process, which transformed the difficult problem of high-dimensional field reconstruction into an optimization problem of solving several Gaussian distribution parameters. The feasibility and effectiveness of this method were verified by simulation experiments, demonstrating that it can achieve accurate dynamic estimation of heat source distribution during solidification.

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Tacit process knowledge acquisition methods for the parts machining
ZHANG Yiming, LIU Jinfeng, CHEN Yajie, QU Pengfei, JING Xuwen, LIU Xiaojun
2024, 45(2): 399-408.  DOI: 10.11996/JG.j.2095-302X.2024020399
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With the widespread application of digital processes in the manufacturing industry, how to efficiently utilize the accumulated process knowledge has become the key to enhancing the efficiency and quality of process design. However, there are technical bottlenecks in acquiring, describing, and transforming tacit process knowledge, hindering the adoption of the intelligent process design mode. Therefore, a method of acquiring tacit process knowledge for processing complex parts was proposed. Firstly, the equal-width method was employed to discretize the structured process data, a text mining based tacit process knowledge acquisition process was constructed, and tacit process knowledge was expressed through production rules. Then, a knowledge reasoning method was proposed, which combined case-based reasoning and rule-based reasoning. The recognition of tacit process knowledge was achieved using the nearest neighbor algorithm. Finally, the method for acquiring processing tacit process knowledge was effectively validated using complex machining parts of marine diesel engine cylinder heads as the verification object.

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Published as 2, 2024
2024, 45(2): 409. 
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