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Regarding the important roles of accuracy and robustness of tightly-coupled micro inertial measurement unit (MIMU)/global navigation satellite system (GNSS) for unmanned aerial vehicle (UAV). This study aims to explore the efficient method to improve the real-time performance of the sensors.

A covariance shaping adaptive Kalman filtering method is developed. For optimal performance of multiple gyros and accelerometers, a distribution coefficient of precision is defined and the data fusion least square method is applied with fault detection and identification using the singular value decomposition. A dual channel parallel filter scheme with a covariance shaping adaptive filter is proposed.

Hardware-in-the-loop numerical simulation was adopted, the results indicate that the gain of the covariance shaping adaptive filter is self-tuning by changing covariance weighting factor, which is calculated by minimizing the cost function of Frobenius norm. With the improved method, the positioning accuracy with tightly-coupled MIMU/GNSS of the adaptive Kalman filter is increased obviously.

The method of covariance shaping adaptive Kalman filtering is efficient to improve the accuracy and robustness of tightly-coupled MIMU/GNSS for UAV in complex and dynamic environments and has great value for engineering applications.

A covariance shaping adaptive Kalman filtering method is presented and a novel dual channel parallel filter scheme with a covariance shaping adaptive filter is proposed, to improve the real-time performance in complex and dynamic environments.

The modern missile has low uncertain and wide range vibration frequency. The conventional notch filter with the fixed notch frequency is less effective than that of the adaptive notch filter (ANF) in vibration suppression for the time-varying vibration frequency.

To overcome the drawback, a novel method is based on frequency estimators made by interpolation of three discrete Fourier transform (DFT) spectral lines. The modified frequency estimators based on the interpolation of three DFT spectral lines are presented to identify and track the vibration frequency. Then the notch frequencies of multiple ANFs are real-timely tuned according to estimators.

Finally, taking the second-order flexible missile as an example, the performance of the proposed method is verified. The verified simulation results show that multiple ANFs are effective in vibration suppression.

Cascading multiple ANFs to achieve multi-order vibration suppression is more efficient and feasible than conventional fixed-parameter notch filtering.

The frequency estimation method based on three DFT spectral lines proposed in this paper can effectively identify and track signals in the noise environment. Compared with conventional methods, the method pretended in this paper has high identification accuracy and a stronger ability to track signals. It can meet the fast frequency identification requirements of the actual flexible missile.

The purpose of this paper is to design a component synthesis method to suppress the vibration of the flexible spacecraft, which has the constant amplitude force/moment actuator.

The authors proposed a method to construct constant amplitude of time delay and composite coefficient sequences based on the principles of the component synthesis vibration suppression (CSVS). The associated design strategy of the CSVS torque control is also developed. The dynamic model consisting of a single axis rotating rigid central body and a fixed flexibility panel is used to validate the proposed method. Constraint modal and free modal method are both tested to analyse the natural frequencies of the panel and dynamic properties of rigid–flexible decoupling system, under the conditions of known and unknown frequencies. The feasibility of constructing CSVS control force based on the constraint modal frequency is also analysed.

The proposed method can suppress multistage vibration and has arbitrary order robustness for each order frequencies simultaneously. Simulation results show that only the duration time of the actuator has to be set for the proposed method, reasonable vibration suppression effect can be achieved.

The method can be used in spacecraft, especially flexible spacecraft to suppress the vibration; the approach is convenient for engineering application and can be easily designed.

The authors proposed a method to construct constant amplitude of time delay and composite coefficient sequences based on the principles of the CSVS.

The purpose of this paper is to develop an attitude control strategy for the reusable boosted vehicle with large angle of attack, and to remove the cross coupling among roll, pitch and yaw channels.

The coordinated gain scheduling control strategy consists mainly of two parts. First, initially ignoring dynamic coupling, single channel gain scheduling controller is designed based on linearized models, respectively. Second, with respect to main channel gain scheduling controller, coordinated scheduling controller is used to generate intentionally cross coupling to partly cancel inter‐channel cross coupling of reusable boosted vehicle.

A coordinated gain scheduling control strategy is presented, and no such analytical solution can be found for the reusable boosted vehicle.

The design idea of coordinated gain scheduling strategy is straightforward in physical concepts and has great value for engineering applications.

Coordinated gain scheduling control strategy is novel in that single channel gain scheduling design does not involve small perturbation linearization and coordinated channel is scheduled.

This paper aims to explore the use of joint distribution to reduce environmental cost of express delivery in urban logistics.

An optimization model was developed to help design the joint distribution network. A real case in Songjiang University Town of Shanghai, China, was used to explore empirically the potential benefit of the design. Performance of the proposed joint distribution was compared with that of the current distribution design using separate deliveries.

The findings show that, using joint distribution in express delivery, a significant saving in economic cost (up to a reduction of 25%) and environmental cost (up to a reduction of 87%) can be achieved.

This study provides a reference for joint distribution network design for last-mile delivery in urban logistics.

Express delivery companies can explore the use of joint distribution to reduce operating cost and increase distribution efficiency of the industry.

Joint distribution can facilitate maximization of vehicle utilization and reduction of delivery trips. This will help reduce fuel consumption, carbon emission, as well as other externalities, such as noise and traffic congestion.

Research in joint distribution to date focuses mainly on reduction in operating cost only. Consideration of environmental impact is relatively limited. This paper fills the gap in the literature by using a real case to illustrate the significant benefit of joint distribution in reducing the negative impact of urban logistics on the environment.

The purpose of this paper is to assess the impacts on production of five fruit crops from 1961 to 2018 of energy use, CO₂ emissions, farming areas and the labor force in China.

This analysis applied the autoregressive distributed lag-bound testing (ARDL) approach, Granger causality method and Johansen co-integration test to predict long-term co-integration and relation between variables. Four machine learning methods are used for prediction of the accuracy of climate effect on fruit production.

The Johansen test findings have shown that the fruit crop growth, energy use, CO₂ emissions, harvested land and labor force have a long-term co-integration relation. The outcome of the long-term use of CO₂ emission and rural population has a negative influence on fruit crops. The energy consumption, harvested area, total fruit yield and agriculture labor force have a positive influence on six fruit crops. The long-run relationships reveal that a 1% increase in rural population and CO₂ will decrease fruit crop production by −0.59 and −1.97. The energy consumption, fruit harvested area, total fruit yield and agriculture labor force will increase fruit crop production by 0.17%, 1.52%, 1.80% and 4.33%, respectively. Furthermore, uni-directional causality is correlated with the growth of fruit crops and energy consumption. Also, the results indicate that the bi-directional causality impact varies from CO₂ emissions to agricultural areas to fruit crops.

This study also fills the literature gap in implementing ARDL for agricultural fruits of China, used machine learning methods to examine the impact of climate change and to explore this important issue.

The purpose of this paper is to examine the effect of top management’s environmental responsibility audit (ERA) implementation on firms’ investment for environmental protection in China.

The sample comprises firms publicly traded on A-Share in China from 2011 to 2017. The authors used the ordinary least squares regression model to test the relation between ERA implementation and corporate environmental investment.

Firms’ environmental investment increases significantly after the ERA implementation. Compared to state-owned enterprises (SOEs), non-state-owned enterprises (non-SOEs) are more likely to increase their environmental investment after ERA implementation. Moreover, such change is more likely for non-heavily polluting enterprises (non-HPEs) compared to heavily polluting enterprises (HPEs).

This paper provides an in-depth analysis of the positive influence of environmental enforcement on corporate behavior, which could serve as reference for regulators on the latest environmental accounting practice in China and other emerging economies.

This paper shows that clear assignment of environmental responsibility and subsequent assessment of environmental performance are contributing factors to effective and efficient implementation of an environmental management system.

Contributing to accounting and environmental management literature, this paper explains how mandated environmental audit incentivizes firms to deal with environmental issues. Because there is no prior research concerning the mandatory implementation of environmental audit in China, this paper is of high-innovatory value by providing a better understanding of environmental auditing and providing an economic explanation for government intervention as an effective means of mitigating environmental degradation in emerging economies.

The fresh food supply chain industry faces significant challenges in risk management because of the complexity, immature development and unpredictable external environment of imported fresh food supply chains (IFFSCs). This study aims to identify specific risk factors in IFFSCs, demonstrate how these risks are transmitted within the system and provide an analytical framework for managing these risks.

A total of 15 risk factors for IFFSCs through extensive literature review and expert consultation are identified and classified into seven levels using interpretive structural modeling (ISM) to demonstrate the risk transmission path. Fuzzy Matrice d’Impacts Croises-Multiplication Appliance Classement (MICMAC) analysis is then used to analyze the role of each factor.

The interactions of the 15 identified risk factors of IFFSCs, classified into seven levels, are visualized using ISM. The fuzzy MICMAC analysis classifies the factors into four groups, namely, dependent, independent, linkage and autonomous factors, and identifies the relatively critical risk factors in the system.

The findings of this research provide a clear framework for enterprises operating in IFFSCs to understand the specific risks they may face and how these risks interact within the system. The fuzzy MICMAC analysis also classifies and highlights critical risk factors in the system to facilitate the formulation of appropriate mitigation measures.

This study provides enterprises in IFFSCs with a comprehensive understanding of how the risks can be effectively managed and a basis for further exploration. The theoretical model constructed is also a new effort to address the issues of risk in IFFSCs. The ISM and the fuzzy MICMAC analysis offer clear insights for researchers and enterprises to grasp complex concepts.

The purpose of this paper is to investigate the relationships between supply chain quality management (SCQM) and firm performance (including quality safety performance and sales performance) leveraging social co-regulation as a moderator.

Using survey data collected from 203 food manufacturers in China, a series of hierarchical linear modeling analyses were conducted to test hypotheses on the relationships between SCQM and firm performance.

The findings are threefold. First, all three dimensions of food SCQM practices, i.e., supplier quality management, internal quality management, and customer quality management, have significant positive effects on an enterprise's quality safety performance and sales performance. Second, SCQM practices can also increase sales performance indirectly through quality safety performance as a mediator. Third, while social co-regulation has no significant effect on the relationship between supplier quality management and quality safety performance, it has a significant moderating effect on the relationship between internal quality management and quality safety performance, customer quality management and quality safety performance.

This study not only integrates SCQM with social co-regulation but also explores the regulating effect of social co-regulation through empirical analysis, thereby providing a theoretical base for future research. However, this research is confined to China and so the results are not necessarily generalizable to other countries.

The findings inform managers of the importance in enhancing awareness of food quality and safety as well as in improving their sensitivity to salient quality demands of external stakeholders in order to achieve better SCQM practices. The findings can also inform policymakers of the significance in designing a systematic multi-agent cooperation mechanism for food SCQM as well as to build an effective information sharing mechanism for social co-regulation of food safety.

This study contributes to knowledge by empirically examining the relationships of SCQM practices with firm performance. It also expands the scope of SCQM research by incorporating social co-regulation in the study framework.

In the wake of the COVID-19 outbreak understanding the behavioral dynamics and role of knowledge-oriented leadership (KOL) in driving knowledge worker performance (KWP) is paramount for organizations striving to adapt and thrive in the post-pandemic era. Drawing on the path-goal theory, this study explores the impact of KOL on KWP. In addition, this study seeks to examine both the direct and indirect influences of KOL on KWP via digital orientation (DO) and digital citizenship practices (DCP), especially for higher education institutions (HEIs) located in China.

The sample consisted of 319 academic staff from HEIs in China. The study used Smart-PLS 4.0 for analytical examination.

The results indicate that the impact of knowledge-oriented leadership on KWP is negligible. Furthermore, DCP and DO partially mediate the relationship between KOL and KWP. The findings of this research have practical implications for Chinese HEIs and organizations across industries, providing insights into how to navigate the complexities of the post-pandemic work environment and effectively harness digitalization to optimize the KWP.

The implications of this research extend beyond the HEIs, providing organizations in various industries with evidence-based strategies to promote effective leadership, foster digital skills, and cultivate a culture of digital citizenship in the post-pandemic work landscape.

Despite the increasing significance of KOL in the higher education sector, there is a dearth of studies establishing a relationship between KOL and KWP in HEIs. The present study seeks to fill this gap by examining the association among KOL, KWP, DO, and DCP in HEIs during the post-pandemic. This research provides significant contributions to the existing literature on the topic by scientifically exploring the association between KOL and KWP by examining the intervention mechanism of both digital citizenship practices and digital orientation.