Abstract
Purpose
Current virtual simulation platforms provide various tools to generate non-immersive simulation processes purposefully in different domains. The generated simulation processes are adopted for analysis, presentation, demonstration and verification. In the virtual maintenance domain, this intuitive and visual method has benefitted product maintainability design and improvement. Generating an ideal and reasonable non-immersive virtual maintenance simulation is always time-consuming because of the complicated human operations and logical relationships involved. This study aims to propose a semiautomatic approach to increase efficiency in non-immersive virtual maintenance simulation implementation.
Design/methodology/approach
The methodology analyzes the general catalogs of common maintenance tasks and explores the corresponding secondary development approaches of simulation tools that can achieve motion simulation in virtual environments, by focusing on the diversity, complexity and uncertainty in non-immersive virtual simulation process generation. Afterward, a single virtual human motion can be generated by controlling the parameters and indices of the simulation tools. Subsequently, all of the generated single motions are connected logically to simulate the entire maintenance process.
Findings
Instead of selecting various tools, such as that in a traditional method, the proposed methodology analyzes and integrates the necessary basic parameters considering the characteristics of virtual maintenance simulation for a target maintenance activity.
Originality/value
The user can control the predefined parameters to generate the simulation combining several other simple operations in virtual environments. Consequently, the methodology decreases simulation tool selection and logic consideration and increases efficiency to a certain extent in non-immersive virtual maintenance simulation generation.
Details
Keywords
Yuxue Jin, Jie Geng, Zhiyi He, Chuan Lv and Tingdi Zhao
Virtual maintenance simulation is of great importance to help designers find and avoid design problems. During its simulation phase, besides the high precision requirement…
Abstract
Purpose
Virtual maintenance simulation is of great importance to help designers find and avoid design problems. During its simulation phase, besides the high precision requirement, collision detection must be suitable for all irregular objects in a virtual maintenance environment. Therefore, in this paper, a collision detection approach is proposed based on encapsulation for irregular objects in the virtual maintenance environment.
Design/methodology/approach
First, virtual maintenance simulation characteristics and several commonly used bounding boxes methods are analyzed, which motivates the application of encapsulation theory. Based on these, three different encapsulation methods are oriented to the needs of simulation, including encapsulation of rigid maintenance objects, flexible maintenance objects and maintenance personnel. In addition, to detecting collisions accurately, this paper divides the detection process into two stages. That is, in the first stage, a rough detection is carried out and then a tiny slice space is constructed to generate corresponding capsule groups, which will be redetected in the secondary stage. At last, several case studies are applied to illustrate the performance of the methodology.
Findings
The automatic construction algorithm for bounding boxes can be adapted to all forms of objects. The number of detection primitives are greatly reduced. It introduces the reachable space of the human body in maintainability as the collision search area.
Originality/value
The advantages of virtual maintenance simulation could also be advantageous in the industry with further studies. The paper believes this study is of particular interest to the readers of your journal.
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Xinsheng Xu, Jing Lin, Ying Xiao, Jianzhe Yu, Qing Liu and Jie Geng
Product variant design can only be achieved after all its constituent parts have been implemented by variant design. It is necessary to plan the sequence of part variant design…
Abstract
Purpose
Product variant design can only be achieved after all its constituent parts have been implemented by variant design. It is necessary to plan the sequence of part variant design reasonably. The product variant design process involves a large amount of information transfer events at the dimensional level. A reasonable product variant design process needs to make full use of the information transfer characters of parts to decrease the uncertainty of product variant design process. The existing methods of researching the product variant design process mainly focus on resource constraint and activity logic. They are deficient, however, in information transfer resolution and uncertainty management. This paper aims to address these issues.
Design/methodology/approach
This paper identifies the number of dimension transfer paths and the position of dimension locating within a transfer path as being the key factors affecting the information transfer role of dimension. Information transfer utility is proposed to measure the information transfer capability of dimensions and parts. Based on these, a two-stage approach of generating the sequence of part variant design based on information transfer utility is proposed.
Findings
The uncertainty of dimension constraint network is minimal during the product variant design process when parts are implemented by variant design under the sequence generated through a two-stage method based on the information transfer utilities of parts, as does the times of parameter transferring and iteration in dimension constraint network.
Originality/value
Part variant design under the sequence of descending information transferring utilities can decrease the difficulty of implementing product variant design validly and also increase the efficiency. This suggests an innovative method to planning the product variant design process reasonably from the perspective of informatics.
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Keywords
Jie Geng, Yongzhi Sheng and Xiangdong Liu
The purpose of this paper is to design a global robust and continuous control scheme for the attitude tracking control problem of the reentry vehicle with parameter uncertainties…
Abstract
Purpose
The purpose of this paper is to design a global robust and continuous control scheme for the attitude tracking control problem of the reentry vehicle with parameter uncertainties and disturbances.
Design/methodology/approach
First, feedback linearization is applied to the model of reentry vehicle, resulting in three independent uncertain subsystems. Then a new second-order time-varying sliding function is proposed, based on which a continuous second-order time-varying sliding mode control (SOTVSMC) law is proposed for each subsystem. The global robustness and convergence performance of the closed-loop reentry vehicle control system under the proposed control law are proved.
Findings
Simulation is made for a reentry vehicle through the assumption that there is external disturbance to aerodynamic moment and the aerodynamic parameters as well as the atmospheric density are perturbed. The results verify the validity and robustness of the proposed strategy.
Originality/value
The SOTVSMC attitude controller based on feedback linearization is proposed for the reentry vehicle. The advantages of the proposed SOTVSMC are twofold. First, the global second order sliding mode is established, which implies that the closed-loop system is global robust against matched parameter uncertainties and disturbances in reentry. Second, the chattering problem is significantly alleviated.
Details
Keywords
Zhang Yong’an, Geng Zhe and Tian Jie
Science and technology innovation policy has important strategic significance with respect to the promotion of an innovation orientation in our country, and the classification and…
Abstract
Purpose
Science and technology innovation policy has important strategic significance with respect to the promotion of an innovation orientation in our country, and the classification and measurement of regional science and technology innovation policy urgently require research attention.
Design/methodology/approach
In this paper, we use text mining and principal component analysis to analyze the classification and measurement of technology innovation policy based on data obtained from Zhongguancun Science Park.
Findings
The empirical results indicate that regional science and technology innovation policy can be divided into four types: authoritative, guiding, urgent and periodical. The key measurements are function type, intensity, resource supply, funding level and funding effectiveness.
Originality/value
A comparative analysis is performed to investigate the different types of regional science and technology innovation policy measurement. Additionally, the study’s limitations are discussed, and future research directions are proposed.
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Keywords
Xiaohui Li, Jie Geng, Qiang Zhang and Jing Sun
Thruster point assembly mechanism (TPAM) of the electric propulsion system allows to adjust the thrust vector, so that the thrust vector is directed to the satellite center of…
Abstract
Purpose
Thruster point assembly mechanism (TPAM) of the electric propulsion system allows to adjust the thrust vector, so that the thrust vector is directed to the satellite center of gravity (COG) during the satellite on-orbit working period. In this way the impact of disturbance torque caused by deviation of the thrust vector from the satellite COG during thruster ignition can be decreased. Therefore, the control accuracy of satellite is influenced directly by the control accuracy of TPAM. On the other hand, the on-orbit application of TPAM is restricted to the on-orbit computer resource. Therefore, the purpose of this paper is to design a control strategy for TPAM, and the strategy should not only be able to control the TPAM precisely but also be easily implemented by the on-board computer.
Design/methodology/approach
First, the structure and work principle of TPAM are discussed, and the mathematical model based on D-H coordinate system is built for it. Then the fitting methods are utilized to design the control strategy of TPAM. Absolute position fitting-based control strategy and relative position fitting-based control strategy are designed, and the least squares algorithm is introduced for parameter selection.
Findings
Simulations and tests are provided for the TPAM. Compared with the state-of-the-art PD controller, the proposed control strategy shows smaller overshoot and more simple realization. The experiment results are matched with the simulation results and both the experiment and simulation results show the validity of the proposed control strategies.
Practical implications
The designed control strategies can be used for the TPAM of some satellite’s electric propulsion system.
Originality/value
The mathematical model of the TPAM based on D-H coordinate system is given. The absolute position fitting-based control strategy and relative position fitting-based control strategy are proposed. Compared with existing methods, the two control strategies have more simple structure and smaller amount of computations. Furthermore, the relative position fitting-based control strategy achieves high precision with simple structure.
Details
Keywords
Ruoshi Geng, Ruijie Sun, Jie Li, Fan Guo, Wangshuai Wang and Gong Sun
This paper examined the relationship between firm innovativeness and consumer trust in the sharing economy. In addition, the authors examine the mediating effect of organizational…
Abstract
Purpose
This paper examined the relationship between firm innovativeness and consumer trust in the sharing economy. In addition, the authors examine the mediating effect of organizational legitimacy and the moderating effect of social worth.
Design/methodology/approach
To examine the hypotheses, the authors collected data from 276 users of a sharing platform (Didi) in China to conduct empirical research. The “lavaan” packages in R and SPSS were used to analyze the data and test the proposed hypotheses.
Findings
The results reveal that sharing platforms' innovativeness is positively related to consumer trust, and this relationship is mediated by organizational legitimacy. Furthermore, sharing platforms' social worth moderates the relationship between firm innovativeness and organizational legitimacy as well as the indirect effect of firm innovativeness on consumer trust via organizational legitimacy.
Practical implications
This article proposes strategies that enable sharing platforms to increase consumer trust, which can also better promote the development of the sharing economy.
Originality/value
This paper contributes to the literature by focusing on the social attributes of the sharing economy. By building a more detailed model of consumer trust, this paper adds to the knowledge on the influencing mechanism of consumer trust in the sharing economy.
Details
Keywords
Ruibin Geng, Shichao Wang, Xi Chen, Danyang Song and Jie Yu
With the popularity of social media and, recently, live streaming, internet celebrity endorsements have become a prevalent approach to content marketing for e-commerce sellers…
Abstract
Purpose
With the popularity of social media and, recently, live streaming, internet celebrity endorsements have become a prevalent approach to content marketing for e-commerce sellers. Despite the widespread use of social media and online communities, empirical studies investigating the economic value of user-generated content (UGC) and marketer-generated content (MGC) still lag behind. The purpose of this paper is to contribute both theoretically and practically to capture both first-order effects and second-order effects of internet celebrity endorsements on marketing outcomes in an e-commerce context.
Design/methodology/approach
This study conducts a cross-sectional regression to evaluate the economic value of internet celebrity endorsement, and a panel vector autoregressive model is adopted to examine the relationship between celebrities’ and consumers’ content marketing behaviors and e-commerce sales performance. The authors also adopt look-ahead propensity-score matching technique to correct for selection bias.
Findings
The empirical results show that the content generation efforts of marketers and the interaction behaviors between marketers and consumers will significantly influence the e-commerce sales, which refers to the first-order effects of internet celebrity endorsement. Moreover, interactions within the fan community exert second-order effects of content marketing on sales performance.
Originality/value
This paper provides new insights for e-commerce retailers to evaluate the economic values of internet celebrity endorsement, a new content marketing practice in e-commerce platform.
Details
Keywords
The purpose of this paper is to review and describe the teamwork, collaboration and learning experiences involved in meeting the unique challenges of establishing a new digital…
Abstract
Purpose
The purpose of this paper is to review and describe the teamwork, collaboration and learning experiences involved in meeting the unique challenges of establishing a new digital library for Syriac collections. The eBetharké Syriac Digital Library Portal is a collaborative effort between the libraries at Rutgers, The State University of New Jersey, and the Beth Mardutho Syriac Institute, a traditional library of texts, to create a specialized digital library collection online. This digital library features content in and relating to Syriac, an Aramaic dialect spoken in the first century A.D. and for which a great deal of historically significant documents was written during the period.
Design/methodology/approach
This task required effort and research on multiple fronts, including software development; collaboration on technical, interpersonal and policy-based levels; and in overcoming challenges related to the predominant computing platforms installed and in use by potential users of this digital library.
Findings
This collaboration provided significant new challenges and learning experiences among the staff who worked on this project and provides a base upon which our digital library platforms can diversify and be more culturally aware.
Social implications
There have been increasing calls within the academic community for better support in the technological space for this and other contemporary languages of the region. Creation of such a platform and expanding it significantly would benefit scholars of Middle Eastern texts in much the same way digital repositories have revolutionized online text access for the Western world.
Originality/value
The project is unique in that it is believed to the first production-level, digital preservation-specific Syriac digital library of its kind. It supports the display of metadata and descriptive details for digital library objects not just in English, but in Arabic and Syriac languages as well, where appropriate
Details
Keywords
Gustavo Dambiski Gomes de Carvalho, Luis Mauricio Martins de Resende, Hélio Gomes de Carvalho, Joseane Pontes and Rúbia Oliveira Correa
This paper aims to analyze the characteristics of Brazilian micro and small businesses (MSBs) and the main lessons derived from the largest small business innovation support…
Abstract
Purpose
This paper aims to analyze the characteristics of Brazilian micro and small businesses (MSBs) and the main lessons derived from the largest small business innovation support program in the country, the Local Innovation Agents – Agentes Locais de Inovação (ALI) Program.
Design/methodology/approach
In total, 34 papers were selected from the Web of Science and Scopus databases (28), as well as from the Revista de Administração e Inovação – RAI (6), a seminal Brazilian innovation journal. The papers were analyzed in terms of the regional context, methodological approach and main findings. Regional complementary analyzes of some program figures were also performed by Spearman correlation and Wilcoxon signed-rank tests.
Findings
The review revealed a low innovation level among Brazilian MSBs and that the platform (incremental product) and brand (marketing) innovation dimensions were the most developed across different regions and industries. Reviewed papers also showed that all MSBs were able to improve innovation over the program independent of previous management and innovation levels, besides positive relationships between management and innovation. The complementary analysis provided a regional panorama of the program figures and corroborated MSBs innovation improvement.
Research limitations/implications
This review analyzed relevant papers and figures related to the program, summarized main lessons and provided future research venues.
Practical implications
Different innovation strategies reviewed may be implemented by MSBs owners. Policymakers may also benefit from the program experience.
Originality/value
Despite the high number of publications and the relevance of the largest Brazilian innovation support program, there were still no literature reviews comprehending the diverse lessons derived from the ALI Program, as well as a regional panorama of the program figures.