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Open Access
Article
Publication date: 8 May 2018

Aidan Jungo, Mengmeng Zhang, Jan B. Vos and Arthur Rizzi

The purpose of this paper is to present the status of the on-going development of the new computerized environment for aircraft synthesis and integrated optimization methods…

2198

Abstract

Purpose

The purpose of this paper is to present the status of the on-going development of the new computerized environment for aircraft synthesis and integrated optimization methods (CEASIOM) and to compare results of different aerodynamic tools. The concurrent design of aircraft is an extremely interdisciplinary activity incorporating simultaneous consideration of complex, tightly coupled systems, functions and requirements. The design task is to achieve an optimal integration of all components into an efficient, robust and reliable aircraft with high performance that can be manufactured with low technical and financial risks, and has an affordable life-cycle cost.

Design/methodology/approach

CEASIOM (www.ceasiom.com) is a framework that integrates discipline-specific tools like computer-aided design, mesh generation, computational fluid dynamics (CFD), stability and control analysis and structural analysis, all for the purpose of aircraft conceptual design.

Findings

A new CEASIOM version is under development within EU Project AGILE (www.agile-project.eu), by adopting the CPACS XML data-format for representation of all design data pertaining to the aircraft under development.

Research limitations/implications

Results obtained from different methods have been compared and analyzed. Some differences have been observed; however, they are mainly due to the different physical modelizations that are used by each of these methods.

Originality/value

This paper summarizes the current status of the development of the new CEASIOM software, in particular for the following modules: CPACS file visualizer and editor CPACSupdater (Matlab) Automatic unstructured (Euler) & hybrid (RANS) mesh generation by sumo Multi-fidelity CFD solvers: Digital Datcom (Empirical), Tornado (VLM), Edge-Euler & SU2-Euler, Edge-RANS & SU2-RANS Data fusion tool: aerodynamic coefficients fusion from variable fidelity CFD tools above to compile complete aero-table for flight analysis and simulation.

Details

Aircraft Engineering and Aerospace Technology, vol. 90 no. 4
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 6 March 2017

Mengmeng Zhang and Arthur Rizzi

A collaborative design environment is needed for multidisciplinary design optimization (MDO) process, based on all the modules those for different design/analysis disciplines, and…

387

Abstract

Purpose

A collaborative design environment is needed for multidisciplinary design optimization (MDO) process, based on all the modules those for different design/analysis disciplines, and a systematic coupling should be made to carry out aerodynamic shape optimization (ASO), which is an important part of MDO.

Design/methodology/approach

Computerized environment for aircraft synthesis and integrated optimization methods (CEASIOM)-ASO is developed based on loosely coupling all the existing modules of CEASIOM by MATLAB scripts. The optimization problem is broken down into small sub-problems, which is called “sequential design approach”, allowing the engineer in the loop.

Findings

CEASIOM-ASO shows excellent design abilities on the test case of designing a blended wing body flying in transonic speed, with around 45 per cent drag reduction and all the constraints fulfilled.

Practical implications

Authors built a complete and systematic technique for aerodynamic wing shape optimization based on the existing computational design framework CEASIOM, from geometry parametrization, meshing to optimization.

Originality/value

CEASIOM-ASO provides an optimization technique with loosely coupled modules in CEASIOM design framework, allowing engineer in the loop to follow the “sequential approach” of the design, which is less “myopic” than sticking to gradient-based optimization for the whole process. Meanwhile, it is easily to be parallelized.

Details

Aircraft Engineering and Aerospace Technology, vol. 89 no. 2
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 4 May 2012

Mengmeng Zhang and Arthur Rizzi

The goal for this paper is to bring the easy‐to‐use geometry drawing software RDS to a “solid” mesh, which could be analyzed and simulated in CEASIOM, to enhance both CEASIOM and…

Abstract

Purpose

The goal for this paper is to bring the easy‐to‐use geometry drawing software RDS to a “solid” mesh, which could be analyzed and simulated in CEASIOM, to enhance both CEASIOM and RDS's capabilities.

Design/methodology/approach

The RDSSUMO interface is developed based on the feature that both RDS and SUMO define their geometric model using cross‐sectional information, i.e. their “universe” shapes are close to each other.

Findings

The translation is automated and allows the engineer to easily modify and augment the geometry in the process. Two test cases are shown, with their high quality Euler mesh and CFD computations. The A321‐look‐alike test case tests the mesh quality for transonic aerodynamics, such as high‐speed trim and drag divergence; the twin‐prop asymmetric aircraft is a “diffi+cult” non‐conventional configuration analyzed for yaw stability in one‐engine out mode.

Practical implications

This paper shows that the CFD solutions based on solid grids could be obtained once the design is proposed and the RDS wire‐frame model is available. The aerodynamic properties can then be predicted in early design stage, which is very efficient for preliminary aircraft design.

Originality/value

This fast meshing tool could obtain “working” grids of a new design within hours.

Details

Aircraft Engineering and Aerospace Technology, vol. 84 no. 3
Type: Research Article
ISSN: 0002-2667

Keywords

Abstract

Details

China Agricultural Economic Review, vol. 10 no. 1
Type: Research Article
ISSN: 1756-137X

Content available
Article
Publication date: 4 May 2012

Askin T. Isikveren

385

Abstract

Details

Aircraft Engineering and Aerospace Technology, vol. 84 no. 3
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 19 October 2023

Lingyun Huang, Jiankun Liu and Zhigang Huang

The operational framework of external financing in the correlation between the gender of entrepreneurs and firm performance remains to be resolved. This study aims to investigate…

Abstract

Purpose

The operational framework of external financing in the correlation between the gender of entrepreneurs and firm performance remains to be resolved. This study aims to investigate the mediating effect of external financing on gender-based disparities in private firm performance and to explore its heterogeneity within the Chinese context.

Design/methodology/approach

Based on national data from the 10th to 13th Chinese Private Enterprise Survey, this study used a bootstrap-based mediation effect model to analyze the role of external financing as a mediator in the relationship between entrepreneur gender and firm performance.

Findings

This study found that external financing is a constructive mediator between entrepreneur gender and firm performance. Heterogeneity analysis revealed that external financing plays a complementary mediation role in the impact of entrepreneur gender on performance in West China. In the tertiary industry, external financing acts as the sole mediator for the impact of gender on firm performance. Notably, this mediating effect is present in non-startups but not in startups.

Practical implications

The findings suggest that external financing can improve the firm performance of female entrepreneurs. Governments and policymakers should strengthen financial support for female entrepreneurs in West China, tertiary industry and non-startup enterprises.

Originality/value

This paper contributes to the literature on gender and corporate governance by shedding light on the mediating role of external financing in the relationship between the gender of business owners and firm performance.

Details

Gender in Management: An International Journal , vol. 39 no. 3
Type: Research Article
ISSN: 1754-2413

Keywords

Article
Publication date: 29 October 2021

Hongyan Jiang, Mengmeng Xu, Peizhen Sun and Jing Zhang

Mixed products, while presenting new business opportunities, raise considerable concerns among managers and researchers. However, whether mixed products (functionally vs…

Abstract

Purpose

Mixed products, while presenting new business opportunities, raise considerable concerns among managers and researchers. However, whether mixed products (functionally vs culturally) trigger positive or negative consumer reactions is controversial. Hereby, the present research seeks to resolve the conflicting effects by examining the moderating role of service provider type (humanoid service robot vs human employee) in the impact of mixed products on consumer reactions.

Design/methodology/approach

Two studies were conducted to explore the effect of mixed products on consumer reactions. Specifically, study 1 was developed to examine the interplay of mixed products and service provider type in shaping consumers' product attitudes and purchase intentions under an offline shopping scenario; study 2 further provided evidence for the mediating roles of perceived usefulness and perceived enjoyment in the above processes under an online-shopping context.

Findings

The convergent findings of two studies conclude that, when served by a humanoid service robot (vs human employee), consumers exhibit more positive attitudes and higher purchase intentions toward functionally (vs culturally) mixed products. Furthermore, such effect is driven by the perceived usefulness (vs perceived enjoyment) when served by humanoid robot (vs human employee).

Originality/value

First, this is one of the first studies to conceptualize mixed products as the two-dimensional construct (i.e. functionally mixed and culturally mixed), and the findings sheds light on the mixed products literature. Second, this paper introduces service provider type as the boundary condition for the impact of mixed products on consumers' product attitudes and purchase intentions, which expands the match-up hypothesis and schema theory in service marketing. Third, the current research explores the mediating roles of perceived usefulness and perceived enjoyment in the above effects, which could make significant contribution to the motivation theory.

Details

International Journal of Emerging Markets, vol. 17 no. 4
Type: Research Article
ISSN: 1746-8809

Keywords

Article
Publication date: 18 October 2018

Zhi Guo, Zhongde Shan, Dong Du, Mengmeng Zhao and Milan Zhang

This paper aims to determine how the viscosity and curing agent content affect the flowability of moist silica sand granules. In addition, a coating device was designed according…

Abstract

Purpose

This paper aims to determine how the viscosity and curing agent content affect the flowability of moist silica sand granules. In addition, a coating device was designed according to the flow properties of silica sand granules.

Design/methodology/approach

The flowability of silica sand granules premixed with two curing agents of different viscosities is studied using a Jenike shear apparatus. An open-ended device was used in discharge testing of sand granules with a design based on the variable dip angle of the two plates and variable outlet size.

Findings

The test results show that increasing the curing agent content would significantly decrease the flowability of silica sand granules, and a curing agent of higher viscosity has a greater effect on the flowability of silica sand. The presence of a curing agent strengthens the cohesion among sand granules, lubricates them and restrains their deformation. The shape function of the coating device was obtained by theoretical derivation.

Practical implications

The flow properties provide a valuable theoretical guidance for the design of coating device for sand mold printing.

Originality/value

This paper deals with experimental work on flow properties of silica sand granules with different viscosities and curing agent content. The shape function of a wedge-shaped coating device is obtained based on experimental data.

Details

Rapid Prototyping Journal, vol. 24 no. 9
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 25 April 2024

Mengmeng Shan and Jingyi Zhu

This paper aims to investigate the relationship between corporate environmental, social and governance (ESG) ratings and leverage manipulation and the moderating effects of…

Abstract

Purpose

This paper aims to investigate the relationship between corporate environmental, social and governance (ESG) ratings and leverage manipulation and the moderating effects of internal and external supervision.

Design/methodology/approach

The authors draw on a sample of Chinese non-financial A-share-listed firms from 2013 to 2020 to explore the effect of ESG ratings on leverage manipulation. Robustness and endogeneity tests confirm the validity of the regression results.

Findings

ESG ratings inhibit leverage manipulation by improving social reputation, information transparency and financing constraints. This effect is weakened by internal supervision, captured by the ratio of institutional investor ownership, and strengthened by external supervision, captured by the level of marketization. The effect is stronger in non-state-owned firms and firms in non-polluting industries. The governance dimension of ESG exhibits the strongest effect, with comprehensive environmental governance ratings and social governance ratings also suppressing leverage manipulation.

Practical implications

Firms should strive to cultivate environmental awareness, fulfil their social responsibilities and enhance internal governance, which may help to strengthen the firm’s sustainability orientation, mitigate opportunistic behaviours and ultimately contribute to high-quality firm development. The top managers of firms should exercise self-restraint and take the initiative to reduce leverage manipulation by establishing an appropriate governance structure and sustainable business operation system that incorporate environmental and social governance in addition to general governance.

Social implications

Policymakers and regulators should formulate unified guidelines with comprehensive criteria to improve the scope and quality of ESG information disclosure and provide specific guidance on ESG practice for firms. Investors should incorporate ESG ratings into their investment decision framework to lower their portfolio risk.

Originality/value

This study contributes to the literature in four ways. Firstly, to the best of the authors’ knowledge, it is among the first to show that high ESG ratings may mitigate firms’ opportunistic behaviours. Secondly, it identifies the governance factor of leverage manipulation from the perspective of firms’ subjective sustainability orientation. Thirdly, it demonstrates that the relationship between ESG ratings and leverage manipulation varies with the level of internal and external supervision. Finally, it highlights the importance of governance in guaranteeing the other two dimensions’ roles by decomposing overall ESG.

Details

Sustainability Accounting, Management and Policy Journal, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2040-8021

Keywords

Article
Publication date: 27 January 2022

Zizhen Geng, Mengmeng Xiao, Huili Tang, Julie M Hite and Steven J Hite

This study develops a cross-level moderated mediating model based on expectation-value theory to extend the knowledge on how and when organizational culture motivates employee…

Abstract

Purpose

This study develops a cross-level moderated mediating model based on expectation-value theory to extend the knowledge on how and when organizational culture motivates employee radical creativity.

Design/methodology/approach

Based on longitudinal, multisource data for 584 R&D employees in 73 organizations, the research hypotheses were tested by a multilevel analysis using hierarchical linear model.

Findings

The results showed that error management culture had a positive effect on employees' psychological safety and radical creativity; psychological safety mediated the effect of error management culture on employee radical creativity. Further, moderated path analysis revealed that employees' promotion focus moderated the positive effect of psychological safety on employee radical creativity and thus strengthened the indirect effect of error management culture on employee radical creativity via psychological safety.

Originality/value

Literature on how organizational culture motivates workplace creativity pays little attention to employees' radical creativity. This study fills this gap by empirically examining the role of error management culture as a critical organizational culture that secures employee radical creativity. It also provides a novel mechanism, i.e., an expectancy-value mechanism to explain the link between organizational context and radical creativity by elucidating the underlying psychological process whereby error management culture drives employee radical creativity and identifying the pivotal moderating role of employees' regulatory focus in the function of error management culture.

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