Search results

As the limited energy of wireless sensor networks (WSNs), energy-efficient data-gathering algorithms are required. This paper proposes a compressive data-gathering algorithm based on double sparse structure dictionary learning (DSSDL). The purpose of this paper is to reduce the energy consumption of WSNs.

The historical data is used to construct a sparse representation base. In the dictionary-learning stage, the sparse representation matrix is decomposed into the product of double sparse matrices. Then, in the update stage of the dictionary, the sparse representation matrix is orthogonalized and unitized. The finally obtained double sparse structure dictionary is applied to the compressive data gathering in WSNs.

The dictionary obtained by the proposed algorithm has better sparse representation ability. The experimental results show that, the sparse representation error can be reduced by at least 3.6% compared with other dictionaries. In addition, the better sparse representation ability makes the WSNs achieve less measurement times under the same accuracy of data gathering, which means more energy saving. According to the results of simulation, the proposed algorithm can reduce the energy consumption by at least 2.7% compared with other compressive data-gathering methods under the same data-gathering accuracy.

In this paper, the double sparse structure dictionary is introduced into the compressive data-gathering algorithm in WSNs. The experimental results indicate that the proposed algorithm has good performance on energy consumption and sparse representation.

Human resource practices are transforming at a varying pace for different businesses to meet the increasingly intensified external challenges. The pursuit of innovation while balancing the tensions between flexibility and efficiency has become a core challenge for survival in this globally competitive era. The literature identifies ambidexterity as a realistic choice to manage these tensions during transformation towards diversified and innovative human resource practices. Based on social exchange theory (SET), this study explores the impact of ambidextrous human resource practices (AHRPs) on organization members' innovation performance while examining the mediating effect of psychological safety.

Data were collected for this cross-sectional study in three waves, and the final sample included 788 employees from 32 companies across different industries in China.

The results of data analysis indicate support for all the hypothesized relationships. AHRPs positively affect employee innovation performance; employee psychological safety mediates this relationship; inclusive leadership moderates the direct effect of AHRPs on employee psychological safety and the indirect effect of AHRPs on employee innovative performance through psychological safety. Theoretical and practical implications of the study are also presented.

This study examines AHRPs’ influence on employee innovation performance mediated by psychological safety and the moderating role of inclusive leadership in the above relationship to clarify the boundary conditions of AHRPs' effect on innovation performance.

The purpose of this paper is to analyse the impact of ownership structure on firm valuation and performance across different geographical regions within mainland China.

The authors classify China in six geographical regions and use cross-sectional data of companies with A-shares listed on domestic stock exchanges in China for the year-end 2015. Using data from CSMAR and Wind database, they use multivariate regression technique and analytically compare the consistency of relationship between operational variables of ownership structure with corporate performance and evaluation.

The authors find that institutional ownership and state ownership negatively affect market valuation throughout various geographical regions of China. Further, in East, Northwest, South Central and Southwestern parts of China, managerial ownership and concentration of shareholding among top ten shareholders positively influence return on equity (ROE). Interestingly, institutional shareholding negatively affects return on assets (ROA), while institutional ownership has a neutral effect on profitability margin in Northeast China. Although in northern part of China, this relationship is slightly positive. In East China region, state ownership and ownership concentration are directly proportional to profitability margin.

As some of the findings exhibit weak state of market efficiency in some regions, the study may also be useful in identifying arbitrage opportunities across different regions. Moreover, this study suggests that regions with the same business environment and conditions anywhere around the globe invite same or similar ownership structure for better firm performance and valuation.

The study provides unique understanding of relationship between ownership structure, market valuation and firm performance in various parts of China and will be an addition to the relevant literature. Given a change in company’s ownership structure and considering its region of incorporation, this study will help investment analysts in assessing performance and market valuation of the firm. It will also assist several classes of investors, financial institutions and international businesses in making their investment decisions.

This paper aims to study the application of reinforcement learning (RL) in the control of an output-constrained flapping-wing micro aerial vehicle (FWMAV) with system uncertainty.

A six-degrees-of-freedom hummingbird model is used without consideration of the inertial effects of the wings. A RL algorithm based on actor–critic framework is applied, which consists of an actor network with unknown policy gradient and a critic network with unknown value function. Considering the good performance of neural network (NN) in fitting nonlinearity and its optimum characteristics, an actor–critic NN optimization algorithm is designed, in which the actor and critic NNs are used to generate a policy and approximate the cost functions, respectively. In addition, to ensure the safe and stable flight of the FWMAV, a barrier Lyapunov function is used to make the flight states constrained in predefined regions. Based on the Lyapunov stability theory, the stability of the system is analyzed, and finally, the feasibility of RL in the control of a FWMAV is verified through simulation.

The proposed RL control scheme works well in ensuring the trajectory tracking of the FWMAV in the presence of output constraint and system uncertainty.

A novel RL algorithm based on actor–critic framework is applied to the control of a FWMAV with system uncertainty. For the stable and safe flight of the FWMAV, the output constraint problem is considered and solved by barrier Lyapunov function-based control.

Drawing on the work as calling theory, the purpose of this study is to explore how and when career calling promotes taking charge by focusing on the mediating effects of work meaningfulness and felt obligation and the moderating role of family-friendly human resource practice (FF-HRP).

The authors collected data from 293 supervisor–employee dyads at three time points in southeastern China. Path analysis and bootstrap method were used for hypothesis testing.

Employees' perceived career calling positively affected taking charge through work meaningfulness and felt obligation. The positive effects of career calling on work meaningfulness and felt obligation as well as the indirect effect of career calling on taking charge are stronger when employees perceive high levels of FF-HRP.

Organizational interventions should be designed to enhance employees' sense of calling, and the organization should inspire employees to take charge by awakening their perception of work meaningfulness and obligation. Moreover, FF-HRP should be implemented as a form of organizational support.

This research identifies work meaningfulness and felt obligation as mediators that link career calling to taking charge and reveals the role of FF-HRP in amplifying the positive impact of career calling.

The purpose of this study is to analyze the linear induction motor (LIM) thermal field when the motor passes through the discontinuous area of the secondary plate in rail transit operation.

To study the thermal field when the LIM passes through the discontinuous area of the secondary plate, the two-dimensional (2D) electromagnetic field model of the motor is first established to calculate and analyze the electromagnetic field of the LIM, and then the motor thermal field is calculated according to the calculation results of the motor electromagnetic field. Finally, the heat source (the motor loss) and the heat dissipation coefficient are added to the thermal field calculation model to calculate the motor thermal field.

This study found that the discontinuity of the secondary board would lead to changes in the electromagnetic field of the linear induction motor to change, which would reduce the motor efficiency and increase the loss, resulting in a sudden increase in the temperature field of the motor.

The LIM temperature field calculation when the LIM passes through the discontinuous area of the secondary board could provide an early warning for the potential risks of the LIM in rail transit applications.

The purpose of this study is to present a system dynamic (SD)-based remanufacturing economic analysis model of used automobile engine under two recycling modes. The authors will compare the remanufacturing cost, sales profit and sales revenue from time and space dimensions incurred in different recycling modes in the long run.

The remanufacturing economic analysis model is based on SD methodology. The authors can simulate the relations of impact factors on automobile engine recycling and remanufacturing and further analyze and compare the cost, sales profit and sales revenue incurred in different recycling modes in the long term.

Sinotruk Steyr engine remanufacturing in Shandong province is taken as the research case subject. The revenue, cost and profit under the two recycling modes from 2015 to 2035 are analyzed and compared. The results show that different recycling modes have significant varying influence on the economy of engine remanufacturing.

This economic analysis model can provide a method reference to decide the recycling mode for auto components and other product remanufacturing. Moreover, this model can guide and support the sustainable development of remanufacturing industry.

This paper aims to explore the effect of fairness concerns on supply chain members' optimal decisions and profits, to compare their profits under different policies, and to investigate the impact of each policy on members, consumers, and the environment with fairness concerns.

Considering government policies and fairness concerns in recycling management, this paper develops five recycling and remanufacturing decision models (anarchy policy model, reward-penalty mechanism model, recycling investment subsidies model, government tax model, and fund subsidy system model). In each model, the manufacturer and the online platform form the Stackelberg game. This research further discusses comprehensive environmental benefits and consumer surplus under five scenarios.

First, the fairness concerns of the online platform inhibit the recovery rate and supply chain members' profit while increasing the platform's utility. Second, fairness concerns increase the profit gap between the manufacturer and online platform, and the higher the degree of fairness concerns, the greater the profit gap; however, the four policies reduce the profit gap. Finally, when there are fairness concerns, environmental taxes damage the interests of supply chain members and consumers, but are most beneficial to the environment; recycling investment subsidies are on the contrary; the fund subsidy system depends on the relative size of the treatment fund and the subsidy fund.

This paper provides useful insights on how to regulate government policy to improve supply chain management with fairness concerns.

This study attempts to determine the optimal pricing and warranty strategies for remanufactured products offered by independent remanufacturers (IRs). Specifically, it takes into account price competition and warranty service competition between the original equipment manufacturer (OEM) and IR, ultimately providing recommendations on the selection of warranty service modes for IRs.

This study considers two warranty modes for IRs: in-housing and outsourcing. Based on game theory, this study identifies the conditions under which the warranty service for remanufactured product is outsourced to retailers in IR-remanufacturing mode. Furthermore, this study investigates how this strategic decision affects closed-loop supply chain (CLSC) operations by comparing the two modes in terms of profit, consumer surplus (CS), quantity and overall social welfare (SW).

Firstly, the provision strategy for IRs' warranty on remanufactured products depends mainly on the retailer’s warranty cost. If retailers have lower costs for warranties, IR opts to outsource the remanufactured product warranty to the retailer. Second, when retailers offer warranties at a lower cost, IRs prefer outsourcing remanufactured product warranty to retailers. In this way, it will maximize both the remanufacturer’s and retailer’s profits while achieving the optimal total profit for the entire supply chain. However, it’s not beneficial for the OEM. Third, the IR’s preference for warranty service provision strategy is influenced by customers’ acceptance of remanufactured product, customer sensitivity toward remanufactured product warranty and economies of scale in warranty service.

The findings offer operational insights into IR decision-making in selecting warranty service provision strategies for remanufactured products.

This study is among the first to examine warranty provision strategy for IRs in CLSC.