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Article
Publication date: 16 October 2018

Wenxiong Lin, Huagang Liu, Haizhou Huang, Jianhong Huang, Kaiming Ruan, Zixiong Lin, Hongchun Wu, Zhi Zhang, Jinming Chen, Jinhui Li, Yan Ge, Jie Zhong, Lixin Wu and Jie Liu

The purpose of this paper is to explore the possibility of an enhanced continuous liquid interface production (CLIP) with a porous track-etched membrane as the…

Abstract

Purpose

The purpose of this paper is to explore the possibility of an enhanced continuous liquid interface production (CLIP) with a porous track-etched membrane as the oxygen-permeable window, which is prepared by irradiating polyethylene terephthalate membranes with accelerated heavy ions.

Design/methodology/approach

Experimental approaches are carried out to characterize printing parameters of resins with different photo-initiator concentrations by a photo-polymerization matrix, to experimentally observe and theoretically fit the oxygen inhibition layer thickness during printing under conditions of pure oxygen and air, respectively, and to demonstrate the enhanced CLIP processes by using pure oxygen and air, respectively.

Findings

Owing to the high permeability of track-etched membrane, CLIP process is demonstrated with printing speed up to 800 mm/h in the condition of pure oxygen, which matches well with the theoretically predicted maximum printing speed at difference light expose. Making a trade-off between printing speed and surface quality, maximum printing speed of 470 mm/h is also obtained even using air. As the oxygen inhibition layer created by air is thinner than that by pure oxygen, maximum speed cannot be simply increased by intensifying the light exposure as the case with pure oxygen.

Originality/value

CLIP process is capable of building objects continuously instead of the traditional layer-by-layer manner, which enables tens of times improvement in printing speed. This work presents an enhanced CLIP process by first using a porous track-etched membrane to serve as the oxygen permeable window, in which a record printing speed up to 800 mm/h using pure oxygen is demonstrated. Owing to the high permeability of track-etched membrane, continuous process at a speed of 470 mm/h is also achieved even using air instead of pure oxygen, which is of significance for a compact robust high-speed 3D printer.

Details

Rapid Prototyping Journal, vol. 25 no. 1
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 12 October 2012

Hu Cao, Yongqiang Bai and Huagang Liu

Rigidity of formation is an important concept in multi‐agent localization and control problems. The purpose of this paper is to design the control laws to enable the group…

Abstract

Purpose

Rigidity of formation is an important concept in multi‐agent localization and control problems. The purpose of this paper is to design the control laws to enable the group to asymptotically exhibit the flocking motion while preserving the network rigidity at all times.

Design/methodology/approach

The novel approach for designing control laws is derived from a smooth artificial potential function based on an undirected infinitesimally rigid formation which specifies the target formation. Then the potential function is used to specify a gradient control law, under which the original system then becomes an orderly infinitesimally rigid formation.

Findings

The strong relationship between the stability of the target formation and the gradient control protocol are utilized to design the control laws which can be proved to make the target formation stable. However, the rigidity matrix is not utilized in the design of control law. Future research will mainly focus on formation control with the relationship of rigidity matrix.

Originality/value

The value of this paper is focused on the control laws design and the control laws could enable the group to asymptotically exhibit the flocking motion while preserving the network rigidity at all times. Also the detailed simulations and experiments are given to prove that the novel approach is available.

Article
Publication date: 2 June 2022

Yang Yi, Jianjun Zhu and Huagang Tong

This study constructs a three-stage evaluation model for interdisciplinary organizations to solve their ranking problems effectively.

Abstract

Purpose

This study constructs a three-stage evaluation model for interdisciplinary organizations to solve their ranking problems effectively.

Design/methodology/approach

A three-stage interdisciplinary organization evaluation model abounds the key problems of “who will evaluate the projects?” and “how to evaluate the projects?”. In the first stage, the authors build a consensus maximization model to identify the selected experts based on the interval grey number because of the uncertainty in assessment. In the second stage, considering the reliability of the experts, the authors calculate the reliability of the experts based on historical data. Meanwhile, considering the gradual changes of the experts, the dynamic weighting method is obtained based on the clustering method. In the third stage, considering decision-makers regret psychological behavior, the authors construct a cross-organizational performance evaluation model based on consensus expectations.

Findings

First, for selecting the experts responsible for assessing interdisciplinary organizations, the consensus-reaching method can effectively avoid cognitive bias. Second, during the assessment, the authors obtained more reasonable results by considering the psychological changes of experts based on regret theory. Third, based on the results, the cross-organization of colleges focused on the achievements of talent training, cross effects, and system construction.

Practical implications

Our study could help organizations establish a suitable assessment mechanism and promote interdisciplinary development.

Originality/value

First, considering the importance of selecting the experts, the authors use the consensus-reaching process for expert selection. This method could guarantee most experts' preferences. Then, the authors propose a two-stage dynamic weighting method, including a pre-determined and adjusted process. The dynamic method can better perform the preferences of experts. Third, the authors studied the assessment in interdiscipline. In addition, based on the framework and considering the features of the interdiscipline, the authors use the grey number to perform the uncertain preferences of the experts using regret theory.

Details

Kybernetes, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0368-492X

Keywords

Article
Publication date: 11 May 2020

Qizhu Yang, Kejian Ma, Huagang Zhang, Yanhui Wei and Ze Xiang

The purpose of this paper is to study the dynamic characteristics and seismic performance of the composite open-web grid floor structure.

Abstract

Purpose

The purpose of this paper is to study the dynamic characteristics and seismic performance of the composite open-web grid floor structure.

Design/methodology/approach

Studied by using mode-superposition response spectrum method and time history analysis method.

Findings

The results show that the vertical mode-superposition response spectrum method is close to the time history analysis method. The floor has strong seismic performance, and the deflection and internal force are not large under vertical seism. The vertical seismic action suggested that 10% of the representative value of gravity load should be used to ensure the safety of the structure.

Originality/value

In the design, the mid-span section should be properly strengthened or the variable section design should be adopted.

Details

International Journal of Structural Integrity, vol. 12 no. 2
Type: Research Article
ISSN: 1757-9864

Keywords

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