Dangshu Wang, Xuan Deng, Zhimin Guan, Shulin Liu, Yaqiang Yang and Xinxia Wang
To simplify the circuit design and control complexity of the magnetic coupling resonant wireless charging system, the radio energy transmission constant current and constant…
Abstract
Purpose
To simplify the circuit design and control complexity of the magnetic coupling resonant wireless charging system, the radio energy transmission constant current and constant voltage charging is realized.
Design/methodology/approach
The purpose of this study is to simplify the circuit design and control complexity of the magnetic coupling resonance wireless charging system, in order to achieve constant current and constant voltage charging for wireless energy transmission. First, the principle of LCC/S-S compensation structure is analyzed, and the equivalent mathematical model is established; then, the system characteristics under constant current and constant voltage mode are analyzed, and the design method of system parameters is given; finally, a simulation and experimental system is built to verify the correctness and feasibility of the theoretical analysis.
Findings
The results show that the proposed hybrid topology can achieve a constant current output of 2 A and a constant voltage output of 30 V under variable load conditions, and effectively suppress the current distortion problem under light load conditions. The waveform distortion rate of the inverter current is reduced from 33.97% to 10.45%.
Originality/value
By changing the high-order impedance characteristics of the compensation structure, the distortion of the current waveform under light load is suppressed, and the overall stability and efficiency of the system are improved.
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This paper considers a supply chain with a manufacturer (she) selling through an online retail platform (he) and studies the channel structure choices of two firms when investing…
Abstract
Purpose
This paper considers a supply chain with a manufacturer (she) selling through an online retail platform (he) and studies the channel structure choices of two firms when investing in advertising.
Design/methodology/approach
The authors assume that the platform provides the manufacturer with an agency and/or reselling channel; thus, there are three possible channel structures: agency channel, reselling channel and dual channel. By developing a game-theoretic model, the authors investigate the channel structure choices of two firms when advertising separately, simultaneously and cooperatively and analyze the optimal combination strategy of channel structure and advertising scheme for both firms.
Findings
When the advertising efforts of the two firms are independent of each other, the equilibrium results show that different advertising schemes lead to different channel choices. For the manufacturer, it is optimal to choose the dual channel structure and adopt the advertising scheme that both subsidizes platform advertising and advertises on her own. For the platform, this combination is also optimal at a high commission rate; otherwise, the advertising scheme in which both firms advertise simultaneously is optimal and he is better off switching from the dual channel structure to the reselling channel structure as interchannel substitution intensity increases. The above results still hold for complementary advertising efforts and asymmetric marginal advertising costs, while in the case of substitutable advertising efforts, one firm may ride on another firm's advertising efforts, leading to different strategic combinations.
Originality/value
This paper not only provides useful guidance for manufacturers and platforms in channel selection and advertising strategy, but also theoretically enriches the literature on manufacturer encroachment.
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Shulin Liu, Rui Ma, Rui Cong, Hui Wang and Haifeng Zhao
Embedding dimension determination in phase space reconstruction is difficult. The purpose of this paper is to present a new approach for embedding dimension determination based on…
Abstract
Purpose
Embedding dimension determination in phase space reconstruction is difficult. The purpose of this paper is to present a new approach for embedding dimension determination based on empirical mode, showing that embedding dimensions for phase space reconstruction could be easily determined according to the number of intrinsic mode functions decomposed by empirical mode decomposition.
Design/methodology/approach
Through the relation analysis of intrinsic mode functions and embedding dimensions, the approach for embedding dimension determination by the number of intrinsic mode functions is presented. First, a time series is decomposed into several intrinsic mode functions. Second, correlation analysis between intrinsic mode functions and original signals is investigated, and then false intrinsic mode functions could be eliminated by the analysis of correlation coefficient thresholds, which makes the embedding dimension precise. Finally, the method presented is applied to the Lorenz system, Chen's system, and the Duffing equation. Simulation results prove this method is feasible.
Findings
A new approach for embedding dimension determination based on empirical mode decomposition is presented. Compared with G‐P algorithms, this new method is effective and decreases computational complexity.
Research limitations/implications
This method provides an effective qualitative criterion to the selection of embedding dimensions in phase space reconstruction.
Practical implications
This method could be used to determine embedding dimensions of phase space reconstruction and degree‐of‐freedom of nonlinear dynamical systems.
Originality/value
The paper proposes a new method of embedding dimension determination in phase space reconstruction.
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Chen Liu, Baofeng Huo, Shulin Liu and Xiande Zhao
The purpose of this paper is to test how integrative mechanisms, including information sharing and process coordination, influence logistics outsourcing, and how logistics…
Abstract
Purpose
The purpose of this paper is to test how integrative mechanisms, including information sharing and process coordination, influence logistics outsourcing, and how logistics outsourcing influence performance from an extended RBV perspective.
Design/methodology/approach
The structural equation modeling (SEM) method is used to examine the proposed model, based on data collected from 361 companies in greater China.
Findings
Integrative mechanisms are helpful for logistics outsourcing (basic, customized, and advanced outsourcing). Specially, information sharing contributes to customized and advanced outsourcing, but has no significant effect on basic outsourcing. In contrast, process coordination improves basic and advanced outsourcing, but insignificantly influences customized outsourcing. Besides, each type of logistics outsourcing has differently effects on 3PL users’ performance. This study contributes to 3PL theories and practices.
Originality/value
This study empirically examines the antecedents and the outcomes of logistics outsourcing, contributing to 3PL literature and practices.
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Xinmeng Hou, Hongji Xie, Shulin Xu, Zefeng Tong and Zeqi Liu
The purpose of this study is to investigate the impact of the accounting system reform on corporate innovation behavior and the heterogeneity and underlying mechanisms of this…
Abstract
Purpose
The purpose of this study is to investigate the impact of the accounting system reform on corporate innovation behavior and the heterogeneity and underlying mechanisms of this impact. This paper further aims to study the impact of accounting system reform on corporate value.
Design/methodology/approach
This study takes China's A-share listed corporates as a sample and uses the exogenous policy shock of the implementation of the New Accounting Standards in 2007 to design the identification strategy of propensity score matching and difference-in-differences method. By comparing the differences between the innovation level of corporates in high-tech industries and non-high-tech industries before and after the implementation of the New Accounting Standards, the impact of the accounting system reform on corporates' innovative behavior can be identified.
Findings
Results show that compared with corporates in traditional industries, high-tech corporates obtained higher patent output after the implementation of the New Accounting Standards. This reform mainly affects corporate innovation by improving corporate risk-taking. In addition, this paper finds that the reform of the accounting system has increased the market value of high-tech corporates in the long run.
Originality/value
This study provides new empirical evidence for addressing the insufficient innovation incentives for market entities and enriches the existing literature on the economic effects of the change of accounting systems and the influencing factors of corporate innovative behavior from the accounting system perspective.
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Wen Liu, Shuangchao Huang, Hongfeng Qi, Xin Zhao, Shulin Liang and Xuesong Jin
Dynamic low adhesion (DLA) has become an urgent problem for the high-speed wheel-rail system because of continuous decrease of adhesion redundancy in the past decades. This…
Abstract
Purpose
Dynamic low adhesion (DLA) has become an urgent problem for the high-speed wheel-rail system because of continuous decrease of adhesion redundancy in the past decades. This article aims to provide a simulation method to reveal the mechanism of DLA under high-frequency vibrations.
Design/methodology/approach
A transient wheel-rail rolling contact model is developed for a typical Chinese high-speed railway system using the explicit finite element (FE) method. Instantaneous adhesion exploitation levels are studied in the time domain, for which driving cases over corrugated rails are taken as an example. A speed up to 500 km/h is considered together with different traction coefficients and corrugation dimensions. DLA is expected when the instantaneous adhesion exploitation level reaches 1.0, that is adhesion saturates and full sliding contact occurs.
Findings
The instantaneous adhesion exploitation level can be very high in the presence of corrugation, even at low traction coefficients. DLA is found to occur as great vertical unloading takes place and causes a significant increase of creepage. An approach is further developed to determine the critical depth of corrugation over which DLA occurs.
Originality/value
This study employs the transient wheel-rail rolling contact model to predict the instantaneous adhesion exploitation level under high-frequency vibrations. The presented results reveal a mechanism of DLA being beneficial to guidelines for future railway practice.
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Hongji Xie, Shulin Xu and Zefeng Tong
This study examines the effect of local government debt (LGD) on corporate earnings management using 25,624 firm-year observations from 2007 to 2019.
Abstract
Purpose
This study examines the effect of local government debt (LGD) on corporate earnings management using 25,624 firm-year observations from 2007 to 2019.
Design/methodology/approach
Pooled ordinary least squares (OLS) regression is used to examine the impact of LGD on earnings management. A difference-in-differences (DID) method is also used to alleviate potential endogeneity.
Findings
Results show that LGD motivates firms to increase earnings management, especially income-decreasing earnings management. Findings are robust to DID method and robustness tests. Heterogeneity analyses show that the positive effect of LGD on earnings management is pronounced in firms with political dependence and moderated by external governance mechanisms. Further discussions indicate that tax enforcement is an underlying channel for LGD to affect earnings management. Firms engage in downward real earnings management by increasing their abnormal discretionary expenditures and higher LGD leads to a greater book-tax difference in those firms that manipulate income-decreasing earnings management.
Originality/value
This study contributes towards examining the political costs hypothesis, the microeconomic effects of LGD and the determinants of earnings management.
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Shu Lin, Lizhong Hao and Shengqiang Liu
The purpose of this study is to examine the audit efficiency and timeliness of Big 4 auditors relative to non-Big 4 auditors, where audit efficiency is defined as the auditor’s…
Abstract
Purpose
The purpose of this study is to examine the audit efficiency and timeliness of Big 4 auditors relative to non-Big 4 auditors, where audit efficiency is defined as the auditor’s ability to conduct an audit more quickly or with fewer resources while still achieving effective outcomes.
Design/methodology/approach
The authors use audit report lags (also referred to as audit delay) as a proxy for audit timeliness and efficiency, controlling for audit quality and audit fees (audit input). The authors use a propensity-score matching (PSM) approach to construct a pseudorandom sample in which each non-Big 4 client is matched with a similar Big 4 client based on their characteristics and audit quality, to control for potential endogeneity related to self-selection bias in this setting.
Findings
The authors find that non-Big 4 auditors are associated with shorter audit delays than Big 4 auditors. Additional analysis of the matched sample reveals that non-Big 4 auditors charge lower fees than Big 4 auditors do after controlling for the Big 4 premium. These findings do not support the notion that Big 4 auditors conduct audits more efficiently than non-Big 4 auditors do.
Originality/value
These results could be of interest to the management of public firms, audit committees, investors and regulators; provide valuable insights into the performance of audit firms in varying client environments; and contribute to a better understanding of audit timeliness and efficiency.
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Hsin Chen, Anastasia Papazafeiropoulou, Ta-Kang Chen, Yanqing Duan and Hsiu-Wen Liu
The purpose of this paper is to understand the factors which impact upon the consumers’ willingness to utilise company Facebook pages and e-word-of mouth by proposing and testing…
Abstract
Purpose
The purpose of this paper is to understand the factors which impact upon the consumers’ willingness to utilise company Facebook pages and e-word-of mouth by proposing and testing a conceptual framework which is inspired by theories in marketing and information systems fields. The authors believe that only by applying both theories will provide a more complete understanding of the relationship between brand experience and Facebook. The research model attempts to illustrate the factors according to customers’ intrinsic and extrinsic motivations and their impact on brand experience, brand Facebook page loyalty and e-word-of-mouth (E-WOM).
Design/methodology/approach
The authors adopted an online survey method for data collection. The subjects the authors used were Facebook users. The data were collected in Taiwan over spring 2011. The authors then used the structural equation model to analyse the data collected.
Findings
The findings suggest that users are influenced by the technical characterises of a brand Facebook page, such as ease of use and usefulness, which might be combated by attempting to reduce customer effort when accessing Facebook pages. The authors conclude that customer effort influenced brand experience and consequently loyalty to brand Facebook pages and E-WOM.
Research limitations/implications
The limitations of this study relate to the investigation of consumer perspectives in a specific geographical context and time frame.
Originality/value
The study's contributions are both theoretical and practical, as it offers new insights into brand experience attitudes in an online environment and useful insights to companies willing to market themselves on Facebook.
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Lidui Wei, Haijun Wei, Shulin Duan and Yu Zhang
The purpose of this paper is to develop a good calculation model to accurately predict the lubrication characteristic of main bearings of diesel engine and improve the service…
Abstract
Purpose
The purpose of this paper is to develop a good calculation model to accurately predict the lubrication characteristic of main bearings of diesel engine and improve the service life.
Design/methodology/approach
Based on the coupling of the whole flexible engine block and the flexible crankshaft reduced by the Component Mode Synthesis (CMS) method, considering mass-conserving boundary conditions, the average flow model equation and Greenwood/Tripp asperity contact theory, an elastohydrodynamic (EHD)-mixed lubrication model of the main bearings for the diesel engine is developed and researched with the finite volume method and the finite element method.
Findings
Obviously, the mixed lubrication of bearings is normal, while full hydrodynamic lubrication is transient. The results show that under the whole flexible block model, maximum oil film pressure, maximum asperity contact pressure and radial shell deformation decrease, while minimum oil film thickness increases. Oil flow over edge decreases, and so does friction loss. Therefore, coordination deformation ability of whole engine block is favorable to mean load. In the whole block model, friction contact happens on both upper shell and lower shell positions. In addition, average oil film fill ratio at the key position becomes smaller in the whole engine block model, and consequently increases the chances of cavitations erosion more. So, wearing resistance of both upper and lower shells and anti-cavitations erosion ability must be enhanced simultaneously.
Originality/value
Based on the coupling of the whole flexible engine block and the flexible crankshaft reduced by the CMS method, considering mass-conserving boundary conditions, the average flow model equation and Greenwood/Tripp asperity contact theory, an EHD-mixed lubrication model of the main bearings for the diesel engine is built, which can predict the lubrication of journal bearings more accurately.