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This paper aims to explore a structural optimization method to achieve the lightweight design of an aviation control stick part manufactured by laser powder bed fusion (LPBF) additive manufacturing (AM). The utilization of LPBF for the fabrication of the part provides great freedom to its structure optimization, further reduces its weight and improves its portability.

The stress distribution of the model was analyzed by finite element analysis. The material distribution path of the model was optimized through topology optimization. The structure and size of the parts were designed by applying honeycomb structures for weight reduction. The lightweight designed control stick part model was printed by LPBF using AlSi10Mg.

The weight of the control stick model was reduced by 32.64% through the optimization method using honeycomb structures with various geometries. The similar stress concentrations of the control stick model indicate that weight reduction has negligible effect on its mechanical strength. The maximum stress of the lightweight designed model under loading is 230.85 MPa, which is 61.81% larger than that of the original model. The lightweight control stick part manufactured by LPBF has good printability and service performance.

A structural optimization method integrating topology, shape and size optimization was proposed for a lightweight AlSi10Mg control stick printed by LPBF. The effectiveness of the optimization method, the printability of the lightweight model and the service performance of LPBF-printed AlSi10Mg control stick was verified, which provided practical references for the lightweight design of AM.

China is a critical factor for constructing an all-round well-off society. Infrastructure construction, especially high-grade highways, in the western area is an essential component of the strategy for large-scale development of west China. It is crucial to evaluate investment projects for high-grade highways and select the best one. Testing investment projects and selecting the best one can be recognized as a multicriteria decision-making (MCDM) problem. In this process, decision-makers (DMs) usually face with uncertain information because of complicated decision environment or their limited knowledge.

A new Evaluation based on the Distance from Average Solution (EDAS) for PFS based on the DEMATEL is proposed: The authors offer a new score function and prove some properties for the score function. They put forward a novel Decision-making Trial and Evaluation Laboratory (DEMATEL) method for PFS to analyze the relations of criteria and get criteria weights. Considering the bounded rationality of DM, the authors propose a new EDAS method for PFS based on prospect theory. They apply their proposed approach to a western city's actual case in selecting a suitable project for building a high-grade highway.

By comparison, the authors can observe that our method has some traits: (1) considering bounded rationality of DM; (2) fewer computation; (3) having the ability to obtain the relation of criteria and finding the critical factor in the decision system.

In this paper, the authors propose a new EDAS method for PFS based on the DEMATEL technique. They transform PFS into crisp numbers by their proposed new score function for PFN to make the decision process more convenient. Then, the authors use the DEMATEL method to obtain the relationship between criteria and criteria weights. Furthermore, they propose a new EDAS method for PFS based on DEMATEL to reduce the computational complexity. Finally, they apply our method to a real case and compare our method with two traditional methods.

What distinguishes digital transformation from other traditional IT transformations is its involvement of the entire organization, rather than merely the IT department. Thus, instead of taking a perspective that is confined to the IT department, this paper studies the ambidextrous nature of digital transformation (DT) from the standpoint of the whole firm. The authors define DT ambidexterity as the capability to utilize digital technology to simultaneously improve the efficiency of existing businesses (DT exploitation) and to promote business growth (DT exploration).

Using annual reports of Chinese firms as a mining material, this paper deploys text mining and word frequency analysis to develop a data set of digital transformation to construct DT exploitation, DT exploration and DT ambidexterity, so that the authors can examine and compare their impact on business performance.

This study's statistics show that observations in this research sample mainly manifest DT ambidexterity and DT exploitation, while DT exploration makes up the smallest proportion. The authors find that DT exploitation, DT exploration, and DT ambidexterity have positive, yet heterogeneous effects on business performance.

This study expands the existing literature of IT-related ambidexterity by examining the ambidextrous nature of DT from the angle of company-wide strategy instead of the perspective from IT-department and expands the extant literature of digital transformation by examining the heterogeneous effects of its different components on business performance. The authors also add to the digital strategizing literature by showing that different business strategy goals can be attained through different stages of DT.

This study expands the existing literature of IT-related ambidexterity by examining the ambidexterity nature of DT from the angle of company-wide strategy instead of the perspective from IT department and expands the extant literature of digital transformation by examining the heterogeneous effects of its different components on business performance. The authors also add to the digital strategizing literature by showing that different business strategy goals can be attained through different stages of DT.

The purpose of this paper is to construct the algebraic traveling wave solutions of the (3 + 1)-dimensional modified KdV-Zakharov-Kuznetsve (KdV-Z-K) equation, which can be usually used to express shallow water wave phenomena.

The authors apply the planar dynamical systems and invariant algebraic cure approach to find the algebraic traveling wave solutions and rational solutions of the (3 + 1)-dimensional modified KdV-Z-K equation. Also, the planar dynamical systems and invariant algebraic cure approach is applied to considered equation for finding algebraic traveling wave solutions.

As a result, the authors can find that the integral constant is zero and non-zero, the algebraic traveling wave solutions have different evolutionary processes. These results help to better reveal the evolutionary mechanism of shallow water wave phenomena and find internal connections.

The paper presents that the implemented methods as a powerful mathematical tool deal with (3 + 1)-dimensional modified KdV-Z-K equation by using the planar dynamical systems and invariant algebraic cure.

By considering important characteristics of algebraic traveling wave solutions, one can understand the evolutionary mechanism of shallow water wave phenomena and find internal connections.

To the best of the authors’ knowledge, the algebraic traveling wave solutions have not been reported in other places. Finally, the algebraic traveling wave solutions nonlinear dynamics behavior was shown.

Complicated tubes extensively exist in the industrial equipment. The manufacturing precision of the tubes is difficult to be ensured with bending machine. Therefore, the tubes’ 3D geometric error should be fixed according to measurement results. However, there are no convenient methods to accomplish the measurement accurately and effectively. Thus, this paper aims to propose a new tube measurement method to achieve tube's automatic measurement. The accurate measurement results can be used to fix the geometric error of the tube to achieve stress-free assembly.

Tubes’ shape can be determined by control points. First, the point clouds of the centre line by multi-stereo-vision technology are reconstructed. Then, the point clouds to the spine of the tube are thinned by moving least-squares and segmented into lines and arcs. Finally, the control points are calculated and the model is reconstructed. The authors can get the tube’s geometric dimensions from the model.

The experiment results indicate that the multi-stereo-vision technology can solve the occlusion problem and measure the complicated tubes efficiently and accurately.

The paper proposed a tube measurement method. The repeatability measuring precision was 0.12 mm, and the absolute measuring precision was within 0.78 mm. The tube spectra assessed in this paper are in the range of angles between two adjacent line segments of 3-177° and the shortest length of the line segment is greater than 5 mm, confirming that the proposed algorithm can measure various complicated tubes effectively and accurately.

Emerging in recent years, digital transformation has become an effective approach for firms to remain competitive in the digital economy. Although this trend has received increasing interest in the business world, there remains a lack of empirical research on the organizational capacities that facilitate digital transformation. To fill this research gap, we investigate the relationship between adaptive capacity configuration and the performance of digital transformation.

We use fuzzy-set qualitative comparative analysis (fsQCA) to identify the impact of adaptive capacity on the digital transformation performance of 38 firms in the household appliance manufacturing, light manufacturing and clothing manufacturing industries (HAMI, LMI, CMI).

Our analysis reveals a Technology-driven transformation configuration for the HAMI, a Market-driven transformation configuration for the LMI and a Market and Management-driven transformation configuration for the CMI, as well as identifies environment scanning capacity as a common basic adaptive capacity. The first configuration is rooted in the innovation mechanism, and the last two configurations are rooted in the integration mechanism.

Enterprises in different industries with unique technology levels require distinctive capacity configurations to implement digital transformation. Each dimension of adaptive capacity plays a particular role in each industry. Environmental scanning capacity requires firms to be agile in their interactions with the digital world and to collect information about the environment.

This study enriches and expands the dimensions of adaptive capacity, and we provide a perspective for researching the digital transformation of manufacturing enterprises through adaptive capability configuration.

This study aims to examine how participation in the Belt and Road Initiative (BRI) affects province-level regional economic resilience. In the context of dual circulation – the new development paradigm proposed by the Chinese Government – participating in the BRI is an important means of connecting both international and domestic circulations and achieving high economic resilience. The complex causal relationship between participation in the BRI and province-level regional economic resilience is investigated.

Based on the complex system view, this study uses fuzzy set qualitative comparative analysis (fsQCA) to examine the impact on regional economic resilience when provinces participate in the BRI through unimpeded trade, infrastructure connectivity, financial integration and people-to-people bonds under the two conditions of attention allocation and buffering capacity. Qualitative textual analysis is applied to analyse provincial work reports, and relevant statistical data are used to measure the economic resilience from 2013 to 2020.

The authors identified three condition configurations that lead to a high regional economic resilience at province-level and one condition configuration that lead to no high-level regional economic resilience.

In-depth analyses of qualitative materials should be conducted to explain the systematic relationships among the conditions.

This research is of practical significance to the development of the theoretical framework and practices of the BRI in the context of dual circulation.

The carbon/carbon (C/C) composite finger seal experiment was performed on a high-speed seal tester. The purpose of this paper is to investigate the leakage and wear characteristics of C/C composite finger seal under various operating conditions.

Static, dynamic, endurance and post endurance tests were carried out. For static and performance tests, the pressure differential changed from 0.1 to 0.6 MPa and the rotor speed varied from 1,000 to 9,000 r/min. Two endurance tests were conducted for 4 h, with each mounting two finger seals. The seal leakage was monitored by mass flowmeters, and the wear depth was measured and calculated by using three-dimensional profilometer.

Results showed that the seal leakage increases with pressure differential but decreases with rotor speed. Leakage rate is lower when speed is decelerated than that with the speed stepped up. During a time history, material removal caused by wear has significant influence on leakage data causing higher leakage than the results before endurance test. Particular interest is that the uneven wear characteristic on finger foot bottom was firstly revealed, showing severe wear in foot heel area than that in foot toe.

This study could provide experimental guidance for finger seal designers. Additionally, the uneven wear characteristic of finger foot was firstly revealed, which showed the necessity of further theoretical research on finger seal wear.

Manufacturing errors, which will propagate along the assembly process, are inevitable and difficult to analyze for complex products, such as aircraft. To realize the goal of precise assembly for an aircraft, with revealing the nonlinear transfer mechanism of assembly error, a set of analytical methods with response to the assembly error propagation process are developed. The purpose of this study is to solve the error problems by modeling and constructing the coordination dimension chain to control the consistency of accumulated assembly errors for different assemblies.

First, with the modeling of basic error sources, mutual interaction relationship of matting error and deformation error is analyzed, and influence matrix is formed. Second, by defining coordination datum transformation process, practical establishing error of assembly coordinate system is studied, and the position of assembly features is modified with actual relocation error considering datum changing. Third, considering the progressive assembly process, error propagation for a single assembly station and multi assembly stations is precisely modeled to gain coordination error chain for different assemblies, and the final coordination error is optimized by controlling the direction and value of accumulated error range.

Based on the proposed methodology, coordination error chain, which has a direct influence on the property of stealthy and reliability for modern aircrafts, is successfully constructed for the assembly work of the jointing between leading edge flap component and wing component at different assembly stations.

Precise assembly work at different assembly stations is completed to verify methodology’s feasibility. With analyzing the main comprised error items and some optimized solutions, benefit results for the practical engineering application showing that the maximum value of the practical flush of the profiles between the two components is only 0.681 mm, the minimum value is only 0.021 mm, and the average flush of the entire wing component is 0.358 mm, which are in accordance with theoretical calculation results and can successfully fit the assembly requirement. The potential user can be the engineers for manufacturing the complex products.

Coordination feature (CF) is the information carrier in dimension and shape transfer process in aircraft manufacturing. The change of its geometric size, shape, position or other attributes would affect the consistency of accumulated errors between two or more assemblies. To identify these “key characteristics” that have a close relationship with the assembly precision, a comprehensive method was developed under digital manufacturing environment, which was based on importance calculation. The multi-hierarchy and multi-station assembly process of aircraft products were also taken into consideration.

First, the interaction and evaluation relationship between components at different manufacturing stages was decomposed with a hierarchical net. Second, to meet coordination accuracy requirements, with the integrated application of Taguchi quality loss function, accuracy principal and error correction coefficient H, the quality loss between target features and candidate features at adjacent assembly hierarchies were calculated, which was based on their precision variation. Third, the influence degree and affected degree of the features were calculated with DEMATEL (decision-making trial and evaluation laboratory) method, and the concepts of centrality degree index and cause degree index were proposed for calculating the complete importance degree to eventually identify the CFs.

Based on the proposed methodology, CFs, affecting the skin profile and the flush coordination accuracy, were successfully identified at different assembly hierarchies to a certain type of wing flap component.

Benefit results for the engineering application showed that the deviation of skin profile was more accurate than before, and the tolerance was also closer to the centerline of required assembly precision range. Moreover, the stability in the assembly process was increased by 26.9 per cent, which could bring a higher assembly quality and an enhancement on aircraft’s flight performance.