GAO Hangshan, HAN Yongzhi, ZHANG Juan and YUE Zhufeng
Based on aerodynamic analysis, an optimization method for the profiles of turbine blade is studied in this paper. This method is capable of addressing multiple objectives and…
Abstract
Based on aerodynamic analysis, an optimization method for the profiles of turbine blade is studied in this paper. This method is capable of addressing multiple objectives and constrains without relying on user input. A quintic polynomial is used to build the three‐dimensional blade model and a three dimensional Navier‐Stokes solver was used to solve the flow field around the turbine blade. The objective functions are the turbine aerodynamic efficiency and total pressure ratio. The optimization is completed with the K‐S function technique and accelerated by approximation technique. Finally, the proposed method is applied to optimizing a true blade to validate its accuracy and efficiency. The obtained result shows that the approximation method is more efficient and accurate than the conventional method.
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Yongzhi Du, Yi Xiang and Hongfei Ruan
The purpose of this study is to examine how the childhood trauma experiences of CEOs influence firms’ internationalization.
Abstract
Purpose
The purpose of this study is to examine how the childhood trauma experiences of CEOs influence firms’ internationalization.
Design/methodology/approach
The research used a difference-in-difference method with constructing a treatment group whose chief executive officer (CEO) experienced the great famine in China between the ages of 7 and 11, and a control group whose CEO was born within three years after 1961.
Findings
The study reveals a significant inverse correlation between CEOs’ childhood trauma experiences and firm internationalization. However, this correlation is weaker in the case of state-owned enterprises and firms led by CEOs with overseas work experience.
Originality/value
To the best of the authors’ knowledge, this study is the first to extend the theoretical framework to elucidate firms’ internationalization by introducing childhood trauma theory into the field of international business literature. Second, the authors link the literature on the effect of CEO explicit traits and psychological traits on firm internationalization by exploring how CEOs’ childhood trauma experience shapes their risk aversion, which, in turn, influences firm internationalization. Third, the authors address the call for examining the interplay of CEO life experiences by scrutinizing the moderating effect of CEO overseas work experience on the association between CEOs’ childhood trauma exposure and firm internationalization.
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Asaad Salam Farooqi, Dian Song, Yishuai Yin and Yongzhi Yuan
This study employs job demands-resources (JD-R) model and self-determination theory (SDT) to examine the double-edged effect of perceived high-performance work systems (HPWS) on…
Abstract
Purpose
This study employs job demands-resources (JD-R) model and self-determination theory (SDT) to examine the double-edged effect of perceived high-performance work systems (HPWS) on employees’ innovative behavior via harmonious passion and obsessive passion. Additionally, the study investigates the cross-level moderating effect of innovative climate on the relationship between perceived HPWS and innovative behavior through the two types of passion.
Design/methodology/approach
Time-lagged data were collected at three points (Time 1, 2 and 3) to mitigate common method variance. Data were collected from Pakistan with 451 respondents from 90 firms.
Findings
Findings reveal that perceived HPWS positively affect employees’ innovative behavior via harmonious passion and negatively influence employees’ innovative behavior via obsessive passion. Moreover, cross-level innovative climate strengthens both the positive and negative impact of perceived HPWS on employees’ innovative behavior.
Originality/value
This study proposes and tests the double-edged effects of perceived HPWS on employees’ innovative behavior, challenging the previous consensus that perceived HPWS is always beneficial for innovative behavior. Besides, we identify organizational innovative climate as a critical condition that amplifies the dual effects of perceived HPWS on employees’ innovative behavior via passion.
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Cheng Luo, Kunlun Zhang, Da Liang and Yongzhi Jing
The purpose of the paper is to study the stability control of permanent magnet (PM) and electromagnetic hybrid Halbach array electrodynamic suspension (EDS) system because of the…
Abstract
Purpose
The purpose of the paper is to study the stability control of permanent magnet (PM) and electromagnetic hybrid Halbach array electrodynamic suspension (EDS) system because of the poor suspension stability caused by the well-known under-damped nature of PM EDS system. The adjustment control is realized by PM and electromagnetic hybrid Halbach array, which is composed by winding active normal conductor coils on PM surface.
Design/methodology/approach
The three-dimensional (3-D) electromagnetic force analytical expression of PM and electromagnetic hybrid Halbach array EDS system for a nonmagnetic conductive plate is derived. And the accuracy of the derived equations is verified by a 3-D finite-element model (FEM). Basing on the 3-D levitation force expression, an acceleration feedback suspension controller is designed to suppress the vibration of PM EDS system, and the suspension stability of the system under the track and load disturbance was simulated and analyzed.
Findings
The 3-D electromagnetic force comparison of analytical model and FEM are in good agreement, which verifies the correctness of the analytical expression. The simulation results show that the acceleration feedback suspension controller can make the system have good suspension stability under the external disturbance. So it proved that the PM and electromagnetic hybrid Halbach array EDS system can overcome the poor suspension stability caused by the under-damped nature of PM EDS system through the designed acceleration feedback suspension controller.
Originality/value
This paper designed an acceleration feedback suspension controller to suppress the vibration of PM and electromagnetic hybrid Halbach array EDS system under external disturbance, basing on the derived levitation force analytical expression. And the simulation results show that the acceleration feedback suspension controller can make the system have good suspension stability under the external disturbance.
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Keywords
- Magnetic levitation
- Control systems
- Electromagnetic fields
- Magnetic force
- Finite element method
- Force calculation
- Suspension stability
- Permanent magnet and electromagnetic hybrid Halbach array
- Electrodynamic suspension
- Electromagnetic force
- Analytical calculation
- Acceleration feedback suspension control