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1 – 3 of 3Jinglong Liu, Zhonghua Wu, Xiaowen Xing and Qizhi He
The purpose of this paper is to find an omnidirectional robust gust response stabilization (GRS) scheme with anti-disturbance and state-limited features.
Abstract
Purpose
The purpose of this paper is to find an omnidirectional robust gust response stabilization (GRS) scheme with anti-disturbance and state-limited features.
Design/methodology/approach
Disturbance observer and barrier Lyapunov techniques, which can, respectively, estimate the lumped disturbances of the dynamic system in real-time and ensure the middle states within some prescribed ranges according to some flight safety indexes.
Findings
In the existing literature, almost all of the GRS controllers are either only for the longitudinal dynamics or only for the latitudinal dynamics. Few studies have considered the gust response alleviation problem with omnidirectional wind disturbance and full aircraft model.
Originality/value
This paper proposes a fresh scheme to deal with a more holistic GRS problem; the disturbance observer based (DOB) barrier Lyapunov backstepping longitudinal controller has been put forward; DOB nonlinear dynamic inversion to handle the multi-input-multi-output lateral dynamics; and to closely connect the two loops of the latitudinal dynamics, a manipulating variable conversion method is proposed.
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Keywords
Xuwei Jin, Shize Huang, Xiaowen Liu, Jing Zhou, Jinzhe Qin, Decun Dong and Xingying Li
Electromagnetic interference (EMI) on communication systems of unban rail transit can hardly be clarified because of complicated factors around railways. This paper aims to target…
Abstract
Purpose
Electromagnetic interference (EMI) on communication systems of unban rail transit can hardly be clarified because of complicated factors around railways. This paper aims to target this issue and extend experimental and theoretical analysis.
Design/methodology/approach
This paper take the Nanjing Dashengguan Bridge as an example, because it carries the most tracks in the world and bears three kinds of trains running through, providing a perfect complex environment. First, it investigates the three communication systems, terrestrial trunked radio, communications-based train control (CBTC) and passenger information system (PIS) that Nanjing Metro uses, and select appropriate devices accordingly. Second, it establishes a system level platform and conduct three tests to analyze their respective operating principles and performance difference under common electromagnetic environments. Third, it adopts theoretical formula to verify test results.
Findings
The experiment results and theoretical analysis mutually corroborate each other and present practical recommendations: an 8 m or more distance between two tracks will ensure no obvious EMI created by a passing train on communication systems; two certain communication systems should not share the same frequency band; interference level is more related to field strength than weathers and building materials; and CBTC DSSS waveguide mode as well as PIS LTE mode are preferred.
Originality/value
This research also provides a practical method of investigating EMI for other complex situations.
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Keywords
Xiaowen Wei and Xiangsheng Dou
Appropriate disposal of end-of-life (EOL) electric vehicle battery (EVB) requires new method of supply chain management (SCM) toward sustainability. Sustainable supply chain…
Abstract
Purpose
Appropriate disposal of end-of-life (EOL) electric vehicle battery (EVB) requires new method of supply chain management (SCM) toward sustainability. Sustainable supply chain finance (SSCF) is an innovative managerial practice dedicated to release cash flow pressure and improve operational efficiency in supply chain, which has drawn increasing attentions from academia and industry. There has been few researches on the integration of EOL EVB management and SSCF yet. The paper aims to fulfill this research gap and lead to the conjunction of environmental management with economic and social concerns.
Design/methodology/approach
The paper conducts a systematic literature review to discuss the probable SSCF adoption on potential market of EOL EVB disposal.
Findings
The results indicate unsustainable factors and potentials to be explored in current market of EOL EVB disposal. As a solution of sustainable SCM, SSCF can ease the tension between the urgent need of EOL EVB disposal and financing problems in the supply chain, strengthening competitive advantages of EV industry.
Originality/value
The significance of this paper lies in offering an interdisciplinary view by drawing upon key perspectives from the emerging sustainable technology of EVB disposal and its underlying battery second use (B2U) market considering SSCF.
Details