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Product variant design process consists of a series of asynchronous activities. These activities and the logic relations among them are important in constructing general logic workflow structure, which is the foundation of deriving an activity path for variant design business. Traditional process modeling approaches have not defined activities for product variant design and cannot describe the complex relations among these activities because of the lack of logic express elements. Thus, logic workflow structure modeling method is anticipated to meet the requirements of logic description and path generation in product variant design application. This paper aims to address these issues.

The paper identifies the variant design modes of different types of parts and defines their variant design activities. The procedure of constructing general logic workflow structure of product variant design is proposed. Simultaneously, the principles of inferring logic relations among activities are put forward based on their adjacency information and connectivity probability. A general logic workflow structure of product variant design is constructed. Based on this, activity path corresponding to a variant design business can be generated. The algorithm of generating activity path is designed as well. In addition, Boolean vectors of activity path, based on the functional contour matrix of polychromatic set theory, can be inferred, which denotes the functional character of activity path.

A general logic workflow structure for product variant design has been established, which comprises variant design activities and basic process logic nodes. The logic relations among activities can be inferred based on their in-degree/out-degree and connectivity probability. The function character of activity path can also be expressed based on the polychromatic set theory.

The combination of variant design activity and basic process logic node makes diverse variant design business descriptions possible in a general workflow structure. The proposed approach provides evidences for designer to plan and develop product variant design system effectively.

The engineering education accreditation (EEA) is a principal quality assurance mechanism. However, at many education institutions, the most labor-intensive work of EEA process is accomplished manually. Without the support of computer and information technology, the EEA process leads to high labor intensity, low work efficiency and poor management level. The purpose of this paper is to build a complex network model and realize an information management system of talent training program for supporting the EEA process.

Based on polychromatic graph (PG), this paper builds a network model of talent training program for engineering specialty. The related information and data are organized and processed in this network model. From the bidirections of top-down and bottom-up, the user requirements are retrieved automatically in logic layer. Together with the specialty of mechanical engineering, the proposed PG-based network modeling method is applied and the corresponding information management system is realized.

The study results show that the PG-based network modeling method takes full advantages of the strong simulation ability of PG to model the complex network system and has some unique merits in formal expression of problem, efficient processing of information and lightweight realization of system. Further, the information management system of talent training program can reduce the tedious human labor and improve the management level of EEA process dramatically.

This paper proposes a PG-based network modeling method, in which the nodes and the edges can be painted by some unified colors to describe the different kinds of activities and the various types of interactions. Theoretically, this modeling method does not distinguish the activities, the interactions and their properties in graphic symbol and the problem size is diminished about a half. Furthermore, this paper provides an effective experience and idea to the education institutions for implementing the engineering education accreditation, increasing the education management efficiency and promoting the talent training quality.

Three-dimensional computer-aided design (CAD) assembly model has become important resource for design reuse in enterprises, which implicates plenty of design intent, assembly intent, design experience knowledge and functional structures. To acquire quickly CAD assembly models associated with specific functions by using product function requirement information in the product conceptual design phase for model reuse, this paper aims to find an approach for structure-function correlations analysis and functional semantic annotation of mechanical CAD assembly model before functional semantic-based assembly retrieval.

An approach for structure-function correlations analysis and functional semantic annotation of CAD assembly model is proposed. First, the product knowledge model is constructed based on ontology including design knowledge and function knowledge. Then, CAD assembly model is represented by part attributed adjacency graph and partitioned into multiple functional regions. Assembly region and flow-activity region are defined for structure-function correlations analysis of CAD assembly model. Meanwhile, the extraction process of assembly region and flow-activity region is given in detail. Furthermore, structure-function correlations analysis and functional semantic annotation are achieved by considering comprehensively assembly structure and assembled part shape structure in CAD assembly model. After that, a structure-function relation model is established based on polychromatic sets for expressing explicitly and formally relationships between functional structures, assembled parts and functional semantics.

The correlation between structure and function is analyzed effectively, and functional semantics corresponding to structures in CAD assembly model are labeled. Additionally, the relationships between functional structures, assembled parts and functional semantics can be described explicitly and formally.

The approach can be used to help designers accomplish functional semantic annotation of CAD assembly models in model repository, which provides support for functional semantic-based CAD assembly retrieval in the product conceptual design phase. These assembly models can be reused for product structure design and assembly process design.

The paper proposes a novel approach for structure-function correlations analysis and functional semantic annotation of mechanical CAD assembly model. Functional structures in assembly model are extracted and analyzed from the point of view of assembly structure and function part structure. Furthermore, the correlation relation between structures, assembled parts and functional semantics is expressed explicitly and formally based on polychromatic sets.

Assembly Sequence Planning integrating assembly Resources (ASPR) is a trend in industry. Because of the introduction of resource, the complexity of ASPR for complex product increases drastically; besides, the dynamic property of resource and the co‐existence of assembly sequence and disassembly sequence (ASDS) make the problems in ASPR more difficult. The dynamic assembly model (DAM) based on polychromatic sets (PS) theory was proposed to address these issues.

First, a strategy was presented to simplify ASPR, taking advantage of assembly sequence generated in the phase of assembly design which considers no resource. Secondly, the concept of DAM was discussed, and some principles/criteria for DAM modeling were generalized from experience. Then, the DAM was modeled by formalizing its incidence relations as PS matrix, and refined based on the formalized criteria, which were expressed as PS locating and collision relation models. Finally, an application case was studied to demonstrate the effectiveness of the method.

The approach could reduce the complexity of ASPR significantly, and was able to identify dynamic resource, model DAM and handle the co‐existence of ASDS effectively.

The method may change the manual pattern of ASPR in simulation environment, and become a potential tool to change the pattern of traditional ASP which comes to work from scratch, by utilizing the upstream information of product design.

Different from traditional assembly model, DAM was a local model which consists of partial components of product and resource, and the DAM‐based ASPR approach would make the computational complexity of product assembly become more linear than exponential.

The purpose of this paper is to realize the integrated optimization of process planning and scheduling in printed circuit board assembly (PCBA).

Logical and numerical contour matrix is used to describe the constituent of component and machine for different PCBA processes on the basis of polychromatic sets (PS) theory, and a PS model of PCBA is built. A hybrid genetic algorithm (GA) is developed to optimize the component allocation, PCB assignment and assembly sequence simultaneously.

Integration of PCBA process planning and scheduling (PCBAPPS) can bridge the gap between design and manufacturing to guarantee the assembly quality and improve the production efficiency. However, PCBAPPS have to search for the optimal result in their own vast solution space. They are complex combinatorial optimization problems. The optimization of PCBAPPS constructs a unified solution space which includes two sub‐solution space stated above. In this paper, dynamic optimization of PCBAPPS is implemented and the solution efficiency is improved.

PS model holds unified standard form on the basis of logical contour and numerical matrix. It is adopted to describe the static structure and dynamic characteristic of PCBA system and combine with GA to solve the integrated optimization problem of PCBAPPS effectively and dynamically.

The purpose of this paper is to present and develop an ontology-based approach for automatic generation of assembly sequences.

In this approach, an assembly sequence planning ontology is constructed to represent the structure and interrelationship of product geometry information and assembly process information. In the constructed ontology, certain reasoning rules are defined to describe the knowledge and experience. Based on the ontology with reasoning rules, the algorithm for automatically generating assembly sequences is designed and implemented.

The effectiveness of this approach is verified via applying it to generate the assembly sequences of a gear reducer.

The main contribution of the paper is presenting and developing an ontology-based approach for automatically generating assembly sequences. This approach can provide a feasible solution for the issue that mathematics-based assembly sequence generation approaches have great difficulty in explicitly representing assembly experience and knowledge.

The purpose of this paper is to develop an automatic disassembly navigation approach for human interactions in the virtual environment to achieve accurate and effective virtual assembly path planning (VAPP).

First, to avoid the error-prone human interactions, a constraint-based disassembly method is presented. Second, to automatically provide the next operable part(s), a disassembly navigation mechanism is adopted. Finally, the accurate assembly path planning can be obtained effectively and automatically by inversing the ordered accurate disassembly paths, which are obtained interactively in the virtual environment aided with the disassembly navigation matrix.

The applications present that our approach can effectively avoid the error-prone interactive results and generate accurate and effective VAPP.

There are several works that could be conducted to make our approach more general in the future: to further study the basic disassembly direction deducing rules to make the process of determining disassembly direction totally automatic, to consider the hierarchy of the parts in virtual reality system and to consider the space for assembly/disassembly tools or operators.

The approach has the following characteristics: a new approach to avoid the error-prone human interactions for accurate assembly path planning obtaining, a new constraint deducing method for determining the disassembly semantics automatically or semi-automatically is put forward and a new method for automatically identifying operable parts in VAPP is set forward.

This paper aims to propose a new approach for determining a decoupling point in leagile chain, based on Lean and agile criteria regarding market and customer demands and internal capabilities of the chain with the ultimate goal of fulfilling customer needs and increasing chain profit.

In the new approach, Lean and agile criteria have been defined for assessing the effectiveness and efficiency of supply chain. The efficiency and effectiveness ratios have been calculated for Lean and agile processes using input- and output-oriented Banker, Charnes and Cooper (BCC) methods, respectively. Based on the results, inefficient and ineffective units have been addressed and the decoupling point has been determined.

Findings indicate that the decoupling point can be regarded as a borderline between two strategies of Lean and agile production, and fuzzy decoupling point and lean–agile distance can provide the basis for distinguishing the two strategies.

Determining the decoupling point has an important role in dynamic performance of a supply chain. By the proposed approach, managers can estimate the most probable area for the decoupling point. Moreover, by appropriate determination of decoupling point, an organization can increase its public responsibility by appropriate usage of its resources and responding faster to customers’ requirements.

In this study, in addition to determining a decoupling point in a supply chain with the aim of increasing productivity, the subject of leagile strategy of supply chains has been developed.

In the high-speed trains (HSTs) production process, assembly sequence planning (ASP) problems is an extremely core issue. ASP problems influence the economic cost, amount of workers and the working time in the assembly process, seriously. In the design process of HSTs, the assembly sequence is usually given by experience, and the correctness of the assembly sequence is difficult to guarantee by experience and low effectiveness. The ASP based on improved discrete particle swarm optimization (IDPSO) algorithm was proposed to address these issues.

In view of the local convergence problem with basic DPSO in ASP, this paper presents an IDPSO, in which a chosen strategy of global optimal particle is introduced in, to solve the ASP problems in the assembly process of HSTs operation panel. The geometric feasibility, the assembly stability, and the number of assembly orientation changes of the assembly are chosen to be the optimization objective. Furthermore, the influences of the population size, the weight coefficient, and the learning factors to the stability and efficiency of IDPSO algorithm were discussed.

The results show that the IDPSO algorithm can obtain the global optimum efficiently, which is proved to be a more useful method for solving ASP problems than basic DPSO. The IDPSO approach could reduce the working time and economic cost of ASP problems in HSTs significantly.

The method may save the economic cost, reduce the amount of workers and save the time in the assembly process of HSTs. And also may change the method of ASP in design and manufacturing process, and make the production process in HSTs more efficiently.

A chosen strategy of global optimal particle is presented, which can overcome the local convergence problem with basic DPSO for solving ASP problems.

The purpose of this paper is to identify the chromatic approaches in dynamic brand identities, describing and analysing new trends, patterns or shared strategies which seem to be taking place and renunciating the consistent use of corporate colours in some brands.

The research consisted of a qualitative visual content analysis, based on the comparison and scrutiny of 50 dynamic visual identities, verifying the changes that their colours would undergo in their numerous forms of representation and the symbolic associations these would carry. This analysis was performed using three different studies.

The results show that colour in dynamic brands does not follow any consistent pattern regarding its application and none of the most common colour harmonies seem to be an obvious strategic preference.

This research provides insights for brand managers to look at how this dynamic positioning can be successfully implemented without affecting recognition whilst establishing or maintaining customer loyalty, and for brand designers and marketers to clarify how brand guidelines will explain the usage of such colourful approaches.

This paper is a contribution to the knowledge of how a traditional visual element such as colour is being combined, deconstructed and reassembled in the context of modern visual identities. Three patterns are identified, and two of them draw attention to the apparent unnecessity of colour consistency and the way this may affect the relevance of colour in transmitting certain meanings.