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This paper aims to focus on the sensor fault-tolerant control (FTC) for civil aircraft under exterior disturbance.

First, a three-step cubature Kalman filter (TSCKF) is designed to detect and isolate the sensor fault and to reconstruct the sensor signal. Meanwhile, a nonlinear disturbance observer (NDO) is designed for disturbance estimation. The NDO and the TSCKF are combined together and an NDO-TSCKF is proposed to solve the problem of sensor faults and bounded disturbances simultaneously. Furthermore, an FTC scheme is designed based on the nonlinear dynamic inversion (NDI) and the NDO-TSCKF.

The method is verified by a Cessna 172 aircraft model under bias gyro fault and constant angular rate disturbance. The proposed NDO-TSCKF has the ability of signal reconstruction and disturbance estimation. The proposed FTC scheme is also able to solve the sensor fault and disturbance simultaneously.

NDO-TSCKF is the novel algorithm used in sensor signal reconstruction for aircraft. Then, disturbance observer-based FTC can improve the flight control system performances when the system with faults.

The NDO-TSCKF-based FTC scheme can be used to solve the sensor fault and exterior disturbance in flight control. For example, the bias gyro fault with constant angular rate disturbance of a civil aircraft is studied.

Signal reconstruction for critical sensor faults and disturbance observer-based FTC for civil aircraft are useful in modern civil aircraft design and development.

This is the research paper studies on the signal reconstruction and FTC scheme for civil aircraft. The proposed NDO-TSCKF is better than the current reconstruction filter because the failed sensor signal can be reconstructed under disturbances. This control scheme has a better fault-tolerant capability for sensor faults and bounded disturbances than using regular NDI control.

This study aims to explore how relational and contractual governance affect crowdsourcer satisfaction under boundary conditions, including internal (i.e. task complexity) or external (i.e. environmental complexity) factors.

We empirically validate the hypotheses using survey data collected from 255 crowdsourcers on a leading platform (i.e. Zhubajie.com). Partial least squares technique and hierarchical regression analysis are used to test the research model.

Both forms of governance mechanisms positively affect crowdsourcer satisfaction. Task complexity negatively moderates the linkage of relational governance and crowdsourcer satisfaction. However, environmental complexity weakens the positive effect of contractual governance but enhances the effect of relational governance on satisfaction.

This study deepens the current understanding of governance mechanism in crowdsourcing by discovering the effectiveness of contractual and relational governance. We also contribute to the governance and crowdsourcing literature by revealing the mechanisms of how governance takes effect under task and environmental complexities.

To cope with climate change and achieve the dual carbon goal, China has actively promoted the implementation of carbon trading pilot policy, among which the power industry plays an important role in China’s carbon emission reduction work. The purpose of this paper is to study the influence of carbon trading policy on the energy efficiency of power industry and achieve the comprehensive goal of carbon emission reduction, carbon peak and carbon neutralization.

This paper constructs the difference-in-differences model based on 2012–2019 provincial data to study the impact of carbon trading policy on energy efficiency in the power industry and its effect path. Heterogeneity analysis was conducted to compare the effects of carbon trading policy in eastern, central and western regions as well as at different levels of power structures.

Carbon trading policy can significantly improve the energy efficiency of the power industry, and the policy effect is more significant in eastern and western regions and areas with high power structure. Mechanism analysis shows that carbon trading policy mainly influences the energy efficiency of power industry by environmental protection investment, power consumption demand and industrial structure.

This paper uses provincial panel data to deeply study the influence of carbon trading policy on energy efficiency of the power industry and its effect path. By constructing the difference-in-differences model, this paper empirically analyzes the governance effect of carbon trading policy. Meanwhile, it controls individual and time effects to solve the endogeneity problem prevalent in previous literature.

When the clearance oil film of hydrostatic bearing friction pair is in critical lubrication state, the phenomenon of zero flow of local lubricating oil will aggravate the oil film temperature rise, which needs to be solved.

In this paper, the critical lubrication parameter equation and the oil film temperature rise mathematical model are derived for the new type q1-205 double rectangular cavity hydrostatic bearing. Based on a combination of theoretical analysis, simulation and experimental verification, this paper analyzes the flow characteristics and temperature rise characteristics of the lubricating oil when the hydrostatic bearing is in a critical lubrication state under different operating conditions and finally obtains the critical lubrication state of the oil film.

This study found that the numerical simulations and the derived formulas agree with the results. When the oil film is in critical lubrication, the cross-section side flow of the oil side is almost zero. The heat cannot be taken away in time, resulting in the local temperature rise of the oil film, which causes serious heat accumulation.

It is concluded that the operating condition parameters corresponding to the critical lubrication state provide a theoretical basis for the selection of actual hydrostatic bearing operating conditions, which is of great scientific significance.

To solve the problem of oil film thinning when hydrostatic thrust bearings are overloaded or rotating at high speed, the dynamic pressure formed by tiny oil wedges is used to compensate, and the optimum height of oil wedges is determined by the compensation rate to improve the bearing capacity of hydrostatic thrust bearings.

This research method is aimed at the new type of double rectangular cavity static bearing with microbevel surface of q1-205. The wedge parameters of oil film were defined. The oil film lubrication performance of the bearing with the wedge parameters of 0, 0.02, 0.04, 0.06, 0.08 and 0.10 mm was simulated by the finite volume method, the comprehensive influence law of the wedge-shaped parameters on the vorticity and flow rate of the oil cavity pressure fluid was revealed. Finally, the oil cavity pressure changes of oil films with different wedge parameters under certain load and speed were tested by design experiments, and the theoretical analysis and simulation were verified.

This study found that the oil film wedge shape can well compensate the static pressure loss caused by the high-speed or heavy-duty operation of the bearing, but the dynamic pressure effect of the wedge shape does not always increase with the increase of the wedge height. The oil film exhibits superior lubrication performance in the range of 0.06–0.08 mm.

The original hydrostatic oil pad was designed as a microinclined plane, and the dynamic pressure caused by the microwedge of the oil pad was used to compensate the static pressure loss of the bearing. The lubrication performance of the oil film under the condition of varying viscosity was obtained by using the simulation method.

The purpose of this study is to determine the level of job satisfaction, turnover intentions and performance of Nigerian polytechnic lecturers with PhDs and to empirically examine the relationship between them.

This study adopted a descriptive correlational research design. Thus, an online self-reported questionnaire was used to gather primary data from a purposively selected sample of 167 Nigerian polytechnic lecturers with PhDs. Descriptive statistics and PLS-SEM were employed to analyse the data collected.

Descriptive results showed a low level of job satisfaction, high level of turnover intention and moderate level of performance of Nigerian polytechnic lecturers with PhDs. The structural model indicated a significantly positive link between job satisfaction and performance of Nigerian polytechnic lecturers with PhDs. Additionally, further analysis showed significantly negative links between job satisfaction and turnover intentions and between turnover intentions and performance of Nigerian polytechnic lecturers with PhDs.

There is a paucity of empirical studies on the impact of turnover intention on employee performance, particularly in the Nigerian context. This study provides empirical evidence of the negative impact of turnover intention on lecturer performance in the Nigerian context. Importantly, the findings of this study provide insights into the fundamental issues, which underlie the brain drain of lecturers in higher education institutions, especially in developing countries.

The purpose of the research is to identify the factors contributing to the formation of high-level strategic thinking ability (STA) of Chinese grassroots cadres.

Through in-depth interviews with 20 Chinese grassroots cadres with high-level STA and grounded theory method, this research explores the contributive factors for the formation of the grassroots cadres' STA from a dynamic and long-term perspective.

The formation of STA is an accumulative process based on the interaction between external factors, including wide space for activities, adequate supporting resources, demonstration of role model, and inflection point and internal drivers, including strong sense of self-actualization, high sense of responsibility, thinking enhancement skills, diverse knowledge and high openness. Moreover, the external factors play a more important role in shaping STA in the early growth stage of the grassroots cadres, while in the late stage the internal factors tend to dominate.

The study advises to offer more professional training on STA and take STA as an important factor for Chinese grassroots cadres to compete in a complex socio-political environment in the long term.

(1) This paper investigates into the STA of Chinese grassroots cadres, which are largely ignored in current literature; (2) different from the extant studies which studies the static influencing factors of STA, such as demographic variables, personal traits and organizational characteristics, this paper focuses on the dynamic and long-term factors during the growth of the cadres.

Prefabricated technology is gradually being applied to the construction of subway stations due to its characteristic of mechanization. However, the prefabricated subway station in China is in the initial stage of development, which is prone to construction safety issues. This study aims to evaluate the construction safety risks of prefabricated subway stations in China and formulate corresponding countermeasures to ensure construction safety.

A construction safety risk evaluation index system for the prefabricated subway station was established through literature research and the Delphi method. Furthermore, based on the structure entropy weight method, matter-element theory and evidence theory, a hybrid evaluation model is developed to evaluate the construction safety risks of prefabricated subway stations. The basic probability assignment (BPA) function is obtained using the matter-element theory, the index weight is calculated using the structure entropy weight method to modify the BPA function and the risk evaluation level is determined using the evidence theory. Finally, the reliability and applicability of the evaluation model are verified with a case study of a prefabricated subway station project in China.

The results indicate that the level of construction safety risks in the prefabricated subway station project is relatively low. Man risk, machine risk and method risk are the key factors affecting the overall risk of the project. The evaluation results of the first-level indexes are discussed, and targeted countermeasures are proposed. Therefore, management personnel can deeply understand the construction safety risks of prefabricated subway stations.

This research fills the research gap in the field of construction safety risk assessment of prefabricated subway stations. The methods for construction safety risk assessment are summarized to establish a reliable hybrid evaluation model, laying the foundation for future research. Moreover, the construction safety risk evaluation index system for prefabricated subway stations is proposed, which can be adopted to guide construction safety management.