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To use the 4H-SiC material in integrated circuits for high temperature application, an accurate and simple circuit model of n-channel planar 4H-SiC MOSFET is required.

In this paper, a SPICE model of n-channel planar 4H-SiC MOSFET was built based on the device simulation results and measurement results. Firstly, a device model was simulated with Sentaurus TCAD, with measured parameters from fabricated planar 4H-SiC MOSFET previously. Then the device simulation results were analyzed and parameters for SPICE models were extracted. With these parameters, an accurate SPICE model was built and simulated.

The SPICE model exhibits the same performance as the measured results with different environment temperatures. The simulation results indicate that the maximum fitting error is 0.22 mA (7.33% approximately) at 200 °C. A common-source amplifier with this model is also simulated and the simulated gain is stable at different environment temperatures.

This paper provides a reliable modeling method for n-Channel Planar 4H-SiC MOSFET and reference value for the design of 4H-SiC high temperature integrated circuit.

This study aims to propose a more precise method for robust design optimization of mechanical structures with black-box problems, while also considering the efficiency of uncertainty analysis.

The method first introduces a dual adaptive chaotic flower pollination algorithm (DACFPA) to overcome the shortcomings of the original flower pollination algorithm (FPA), such as its susceptibility to poor accuracy and convergence efficiency when dealing with complex optimization problems. Furthermore, a DACFPA-Kriging model is developed by optimizing the relevant parameter of Kriging model via DACFPA. Finally, the dual Kriging model is constructed to improve the efficiency of uncertainty analysis, and a robust design optimization method based on DACFPA-Dual-Kriging is proposed.

The DACFPA outperforms the FPA, particle swarm optimization and gray wolf optimization algorithms in terms of solution accuracy, convergence speed and capacity to avoid local optimal solutions. Additionally, the DACFPA-Kriging model exhibits superior prediction accuracy and robustness contrasted with the original Kriging and FPA-Kriging. The proposed method for robust design optimization based on DACFPA-Dual-Kriging is applied to the motor hanger of the electric multiple units as an engineering case study, and the results confirm a significant reduction in the fluctuation of the maximum equivalent stress.

This study represents the initial attempt to enhance the prediction accuracy of the Kriging model using the improved FPA and to combine the dual Kriging model for uncertainty analysis, providing an idea for the robust optimization design of mechanical structure with black-box problem.

The purpose of the paper is to make a high speed motor based on the characteristics of high strength silicon steel. With the higher requirements for torque density and power density of the driving system of electric vehicles (EV), conventional magnetic materials have been difficult to meet the demands in the future. In this paper, a new type of high-strength non-grain-oriented (NGO)material is tested.

Through analyzing the characteristic of high strength silicon steel, it is applied to the rotor part of a high-speed motor. A topological optimization is applied to achieve higher power density and higher efficiency of the motor.

The feasibility of the scheme was analyzed by the finite element method, and a prototype was also fabricated to verify the analysis.

In this paper, the characteristics of new soft magnetic materials as a breakthrough to manufacture a new generation of high-performance electrical machine (EM) are discussed. Consequently, the presented work greatly facilitates further explorations and guides the innovative application of soft magnetic materials and the iterative optimization of motor structure.

This paper aims to investigate an identification strategy for the nonlinear state-space model (SSM) in the presence of an unknown output time-delay. The equations to estimate the unknown model parameters and output time-delay are derived simultaneously in the proposed strategy.

The unknown integer-valued time-delay is processed as a latent variable which is uniformly distributed in a priori known range. The estimations of the unknown time-delay and model parameters are both realized using the Expectation-Maximization (EM) algorithm, which has a good performance in dealing with latent variable issues. Moreover, the particle filter (PF) with an unknown time-delay is introduced to calculated the Q-function of the EM algorithm.

Although amounts of effective approaches for nonlinear SSM identification have been developed in the literature, the problem of time-delay is not considered in most of them. The time-delay is commonly existed in industrial scenario and it could cause extra difficulties for industrial process modeling. The problem of unknown output time-delay is considered in this paper, and the validity of the proposed approach is demonstrated through the numerical example and a two-link manipulator system.

The novel approach to identify the nonlinear SSM in the presence of an unknown output time-delay with EM algorithm is put forward in this work.

Effectively engaging patients is critical for the sustainable development of online health communities (OHCs). Although physicians’ general knowledge-sharing, which is free to the public, represents essential resources of OHCs that have been shown to promote patient engagement, little is known about whether such knowledge-sharing can backfire when superfluous knowledge-sharing is perceived as overwhelming and anxiety-provoking. Thus, this study aims to gain a comprehensive understanding of the role of general knowledge-sharing in OHCs by exploring the spillover effects of the depth and breadth of general knowledge-sharing on patient engagement.

The research model is established based on a knowledge-based view and the literature on knowledge-sharing in OHCs. Then the authors test the research model and associated hypotheses with objective data from a leading OHC.

Although counterintuitive, the findings revealed an inverted U-shape relationship between general knowledge-sharing (depth and breadth of knowledge-sharing) and patient engagement that is positively associated with physicians’ number of patients. Specifically, the positive effects of depth and breadth of general knowledge-sharing increase and then decrease as the quantity of general knowledge-sharing grows. In addition, physicians’ offline and online professional status negatively moderated these curvilinear relationships.

This study further enriches the literature on knowledge-sharing and the operations of OHCs from a novel perspective while also offering significant specific implications for OHCs practitioners.

This study aims to explore how the concept of extended self-influences luxury shopping tourism consumption among Chinese tourists. It explores why luxury shopping is important for Chinese tourists. Specifically, this study focuses on a strategically important emerging market segment: post-1990s female Chinese tourists.

To explore the link between the extended self and luxury shopping tourism consumption among post-1990s Chinese female tourists, this study adopted a qualitative and interpretive approach. A total of 22 semi-structured in-depth interviews were carried out to collect the data.

This qualitative inquiry found that luxury shopping during overseas holidays has some subtle differences from luxury shopping in China, as the conceptualisation of luxury is highly context-based. Through a focus on gender and generational differences, the current study reveals that the idea of individuality has started to influence their luxury purchases.

The study shows how different selves are associated with luxury shopping. It thus provides empirical evidence regarding the reasons behind their motivation, especially for shopping overseas to get a good price and an exclusive and enjoyable luxury shopping experience abroad. Also, it was found that curiosity about buying luxury products is viewed as less favoured and logical shopping will be a future trend. Individuality is becoming a trend for younger consumers.

Theoretically, by linking the “extended self” with luxury shopping tourism, this study provides the social-psychological aspects of luxury shopping tourism. Instead of focusing on particular destinations, this study provides compressed but also focused inquiries to explore how the concept of the self-influences post-1990s female Chinese tourists’ shopping consumption while on holiday, and how this luxury shopping experience influences their concept of the self.

本文运用“延伸自我”概念对中国泳客在境外购买奢侈品的行为和意义进行探讨, 从而进一步了解中国游客对奢侈品的消费形态。 研究主要专注在中国90后女性市场, 女性市场已被许多学者以即市场营销人员认定为新兴市场领域。

通过22个深度访谈的所得数据表明境外奢侈品高买行为与自我概念有着紧密的联系, 并为消费者购买动机背后的原因提供了实证

在境外旅游过程中购买奢侈品有非常大的价格优势, 同时又能为消费者提供独特的购物体验, 中国90后女性的奢侈品购买行为日趋理性并在出行之前做好详细的购物计划, 个性的展示将成为中国年轻女性奢侈品消费的主导因素。

该研究的理论贡献是探索自我概念如何影响90年代后中国女性游客在境外旅行度假时的奢侈品购物行为, 以及这种奢侈品购物体验如何影响其自我概念。

关键词 购物，中国游客，女性， 延伸自我，自我概念

文章类型 研究论文

El estudio se dedica a explorar cómo influir el conceptöauto-extensión¨ al comportamiento de comprar los artículos de lujo en el extranjero entre los chinos turísticos, también a explorar la importancia de tal caso para ellos.

Este estudio ha adaptado un enfoque cualitativo entre 22 entrevistas en profundidad semiestructuradas para la recopilación de datos y muestra cómo se asocian diferentes seres con las compras de lujo.

Por lo tanto, se proporciona las pruebas evidentemente sobre las razones detrás de su motivación. Comprar artículos de lujo durante los viajes al extranjero tiene una gran ventaja de precio, al tiempo que las ofrece una experiencia especial. Estos actos se están volviendo más racionales y tienen planes de compras detallados antes de viajar. La exhibición de la personalidad se convertirá en el factor dominante en cuanto al consumo de artículos de lujo por parte de tales chinas.

Principalmente se enfoca a un nuevo campo del mercado en lo cual los consumidores son las chicas quienes nacieron después del año 1990.

The purpose of this paper is to investigate the effect of four controllable parameters (fuel mixture, evaporation bubble point temperature, expander inlet temperature and condensation dew point temperature) of a solar-driven organic Rankine cycle (ORC) on the first-law efficiency, the exergetic efficiency, the exergy destruction and the volume flow ratio (expander outlet/expander inlet).

Nine experiments as per Taguchi’s standard L9 orthogonal array were performed on the solar-driven ORC. Subsequently, multi-response optimization was performed using grey relational and principal component analyses.

The results revealed that the grey relational analysis along with the principal component analysis is a simple as well as effective method for solving the multi-response optimization problem and it provides the optimal combination of the solar-driven ORC parameters. Further, the analysis of variance was also employed to identify the most significant parameter based on the percentage of contribution of each cyclic parameter. Confirmation tests were performed to check the validity of the results which revealed good agreement between predicted and experimental values of the response variables at optimum combination of the input parameters. The optimal combination of process parameters is the set with A3 (the best fuel mixture in the context of optimal performance is 0.9 percent butane and 0.1 percent pentane by weight), B2 (evaporation bubble point temperature=358 K), C1 (condensation dew point temperature=300 K) and D3 (expander inlet temperature=370 K).

In this research, the Taguchi-based grey relational analysis coupled with the principal components analysis has been successfully carried out, whereas for any optimized solution, it is required to have a real-time scenario that may be taken into consideration by the application of different soft computing techniques like genetic algorithm, simulated annealing, etc. The results generated are purely based on theoretical modeling, and, for further research, experimental analyses are required to consolidate the generated results.

This piece of research work will be helpful to users of solar energy, academicians, researchers and other concerned persons, in understanding the importance, severity and benefits obtained by the application, implementation and optimization of the cyclic parameters of the solar-driven ORC.

The purpose of this paper is to examine whether firm-level corporate governance measures and regulatory reforms constrain manipulation of operating cash flows, an important firm performance indicator.

The sample comprises firms from an emerging market, India, with data from 2005 to 2011. The authors use the methodology given in the paper by Lee (2012) and multiple regressions.

The authors find that cash flow manipulation is likely to increase with an increase in the controlling ownership. Furthermore, board diligence and better audit fail to curb such manipulation. However, the authors do find that such manipulation has gone down in the recent years, and diligent boards constrain it, possibly due to the recent steps taken by the Indian Government for improving the corporate governance environment in India.

The findings can act as feedback for the regulators and policy makers. Potential investors and analysts may also benefit from the study, since they can be more vigilant about the firms’ cash flow manipulation practices and can demand better governance.

The findings suggest that good corporate governance makes managers substitute earnings management with cash flow manipulation.

This research examined the effects of information literacy on lifelong learning, creativity, and work performance among journalists in Pakistan.

Survey research design was applied to conduct this research. The participants were recruited through a stratified convenient sampling process from the press clubs of four provinces (e.g. Punjab, Sindh, Khyber Pakhtunkhwa, and Baluchistan) and the federal capital Islamabad with the consent of relevant authorities for data collection. An online questionnaire was distributed among these journalists and a total of 1,089 responses were received. The data were analyzed by applying descriptive and inferential statistics in SPSS.

The results revealed that these journalists perceived themselves as information literate. The information literacy (IL) skills of journalists appeared to have a direct and positive effect on their lifelong learning, creativity, and work performance. In other words, the lifelong learning, creativity, and work performance of journalists increase as their levels of IL skills increase.

These results generated useful insights for academicians and organizations about the importance of IL in the workplace and its influence on organizational effectiveness and performance in gaining a sustainable competitive advantage. This knowledge might be crucial for media employers to initiate training programs for journalists to impart IL education.

This research would be a worthwhile contribution to the existing research on workplace IL, particularly in the context of journalists' workplace as no such comprehensive study using these variables appeared so far.

The peer review history for this article is available at: https://publons.com/publon/10.1108/OIR-06-2022-0345.

Section 404 of the Sarbanes–Oxley Act (SOX) altered the relationship between auditors and their clients by requiring an external audit of companies’ internal controls. Regulatory guidance is interpreted and applied by external auditors to comply with SOX. The purpose of this paper is to apply service operations management theories and techniques to the internal control audit process to better understand the role regulatory guidance plays in audit services. We discuss service operations management theories that apply to the production of audit services and employ the operations management technique of simulation to examine the effects of a historical relationship between the client and the auditor, information sharing between the client and the auditor, and the auditor’s perceived risk of the client on the internal control audit process. The application of service operations management theories and the simulation results illustrate that risk and information sharing are key factors for the audit process. The results suggest the updated Public Company Accounting Oversight Board guidance from Auditing Standard 2 to Auditing Standard 5 appropriately increased audit effectiveness by encouraging risk-based judgments and information sharing. This paper merges accounting and service operations management research to examine the effects of regulatory guidance on the internal control audit process. The paper uses simulation to illustrate the importance of interpreting regulatory guidance and the specific effects of risk and information sharing on the internal control audit process.