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The purpose of this paper is to report on the flow past a porous square cylinder, implementing the stress jump treatments for the porous‐fluid interface.

The numerical method was developed for flows involving an interface between a homogenous fluid and a porous medium. It is based on the finite volume method with body‐fitted and multi‐block grids. The Brinkman‐Forcheimmer extended model was used to govern the flow in the porous medium region. At its interface, a shear stress jump that includes the inertial effect was imposed, together with a continuity of normal stress.

The present model is validated by comparing with those for the flow around a solid circular cylinder. Results for flow around porous square cylinder are presented with flow configurations for different Darcy number, 10⁻² to 10⁻⁵, porosity from 0.4 to 0.8, and Reynolds number 20 to 250. The flow develops from steady to unsteady periodic vortex shedding state. It was found that the stress jump interface condition can cause flow instability. The first coefficient β has a more noticeable effect whereas the second coefficient β₁ has very small effect, even for Re=200. The effects of the porosity, Darcy number, and Reynolds number on lift and drag coefficients, and the length of circulation zone or shedding period are studied.

The present study implements the numerical method based on finite volume method with a collocated variable arrangement to treat the stress jump condition.

Two time metaphors are often adopted to express the passage of time: the ego-moving metaphor that conceptualizes the ego as moving toward the stationary event (e.g. we are approaching the holiday) or the event-moving metaphor that conceptualizes the event as moving toward the stationary ego (e.g. the holiday is approaching us). This paper aims to investigate the influence of the time metaphor on regulatory focus, as well as its downstream marketing implications.

Five studies were conducted. Studies 1a–1c examined the moderating effect of the valence of events on the relationship between time metaphors and regulatory focus. Studies 2–3 investigated the downstream marketing implications of the above effects.

The findings indicated that compared to the event-moving metaphor, the ego-moving metaphor is more likely to evoke a promotion focus when consumers anticipate a positive event. However, when the event is negative, the ego-moving metaphor is more likely to evoke a prevention focus compared to the event-moving metaphor.

This research extends the previous literature on regulatory focus activation by showing that time metaphors affect regulatory focus, and that event valence plays a critical moderating role in the relationship.

Many companies rely on positive events (e.g. holidays, anniversaries) to market their products. The findings of this research suggest that companies promoting products with promotion-related benefits or products with higher risks should adopt an ego-moving metaphor to describe the coming of the event. In contrast, companies promoting products with prevention-related benefits or products with low risks should adopt an event-moving metaphor to describe the coming of the event.

This research showed that the effects of time metaphors on consumers’ regulatory focus depend on the valence of the events. It also demonstrated the downstream implications of time metaphors by showing that time metaphors influence consumer product choices and financial decisions.

This paper aims to present a picture of the past and the present status of the Distance Education College (DEC) of East China Normal University (ECNU). It describes what the DEC has achieved in each phase, and probes into some essential problems that the DEC has attempted to solve.

This article provides a comprehensive description of the development of the DEC by following a case study method.

The DEC goes through three stages. In the first phase, a teacher‐focused policy and disciplined management are formed. In the second phase, a quality‐first policy is emphasized, and two training modes are developed: the human‐centered management mode and the trainee‐oriented training mode. In the third phase, the DEC initiates further innovation and uses a new platform.

ECNU has witnessed and participated in the development of modern distance education in China. It remains successful in developing distance education. The effort made by the DEC well showcases the overall development and growth of modern distance education in China.

This article presents the development of the DEC and will help readers understand the developmental process of distance education colleges in China.

This paper aims to improve the reliability of numerical methods for predicting the transient heat transfers in combustion chambers heated internally by moving heat sources.

A two-phase fluid dynamic model was used to govern the non-uniformly distributed moving heat sources. A Riemann-problem-based numerical scheme was provided to update the fluid field and provide convective boundary conditions for the heat transfer. The heat conduction in the solids was investigated by using a thermo-mechanical coupled model to obtain a reliable expanding velocity of the heat sources. The coupling between the combustion and the heat transfer is realized based on user subroutines VDFLUX and VUAMP in the commercial software ABAQUS.

The capability of the numerical scheme in capturing discontinuities in initial conditions and source terms was validated by comparing the predicted results of commonly used verification cases with the corresponding analytical solutions. The coupled model and the numerical methods are capable of investigating heat transfer problems accompanied by extreme conditions such as transient effects, high-temperature and high-pressure working conditions.

The work provides a reliable numerical method to obtain boundary conditions for predicting the heat transfers in solids heated by expanding multiphase reactive flows.

This study aims to present a numerical study on the flow and heat transfer performance of a water-cooled tube with protrusions in different geometrical parameters.

A new type of enhanced heat exchanger tube is designed. Protrusions are formed on the inner surface of the tube by mechanical expansion, compression and other processing methods. A three-dimensional numerical symmetry model is established by ANSYS for studying the influence of protrusion distance, protrusion radius and protrusion arrangement on flow and heat transfer characteristics in turbulent flow.

The results show that the protrusions increase the heat transfer area and improve the heat transfer effect but also increase the flow resistance. Performance evaluation criteria (PEC) is applied to evaluate the flow and heat transfer characteristics of convex tubes. When adopting the aligned protrusions arrangement, the radius of 2 mm and distance of twice the protrusion radius is most heat transfer effect. The PEC of protrusion tubes with a staggered arrangement are higher than those in aligned arrangement, and the maximum value is 2.36 when Reynolds number is 12,000.

At present, most of the protrusion technology applications are based on the cold plate heat dissipation of electronic devices, and the flow path is rectangular. Convex tube heat exchanger is a high-efficiency heat exchanger, which uses convex tubes instead of smooth tubes in tubular heat exchangers to enhance heat transfer and widely used in petroleum, chemical, textile, oil refining and other industries.

The purpose of this paper is to investigate the relationship between emotional experience and symbolic consumption on brand loyalty. The authors also examine the differences in Generation Y consumer behavior through the comparison of Generation Y consumers’ income sources.

A conceptual model was developed to represent the proposed relationships among the related variables. Data from a total of 328 usable surveys were collected from Thai Generation Y consumers. The proposed hypotheses were tested using structural equation modeling analyses.

The study found that emotional experience has a significant and positive effect experience symbolic consumption, symbolic consumption provided a positive effect on brand loyalty.

Time and resources limitation did not allow studying the larger sample. Future research should include more product categories. The sample can be extended to consumers in ASEAN countries to provide more comprehensive insights into consumer perceptions and brand behaviors.

The findings suggest that symbolic consumption is a key motivation to increase brand loyalty when developing marketing strategies for the Generation Y consumers.

This study identifies the components of symbolic consumption in meaning for conspicuous products and provides empirical support for the effect of emotional experience and symbolic consumption on brand loyalty in coffee shop industry.

The huge flow of foreign direct investment (FDI) in recent decades has prompted concern among policy-makers and researchers regarding its impact on the environment, as well as its contribution to China’s economic growth. In this study, by combining FDI and trade pollution theory, we establish a model to evaluate the impact of FDI on pollution, which facilitates testing the “pollution haven” hypothesis. Our results indicate that FDI is concentrated in pollution-intense industries. Moreover, it is necessary to undertake further research on FDI pollution with new data after environmental regulation.

With the analysis of the causes of corruption, this study aims to investigate specific anti-corruption measures that can be implemented to reform the political system and the social climate of China.

This study examines 97 severe corruption cases of high-ranking officials in China, which occurred between 2012 and 2015. As this insinuates that both institutional and social corruption are major problems in China, the analysis delves into multiple facts of corruption, including different types, four primary underlying causes, and suggestions regarding the implementation of three significant governmental shifts that focus on investigation, prevention tactics and legal regulations.

China’s corruption is not only individual-based but also it has developed into institutional corruption and social corruption. Besides human nature and instinct, the causes of corruption can be organised into four categories, namely, social customs, social transitions, institutional designs and institutional operations. For the removed high-ranking officials, the formation of interest chains was an important underlying cause behind their corruption.

This study makes a significant contribution to the literature because this study provides a well-rounded approach to a complex issue by highlighting the significance of democracy and the rule of law as ways to regulate human behaviour to combat future corruption.

Various simplifications are introduced into the establishment of numerical models for problems with strong nonlinear interactions. The combustion of energetic materials in a chamber with moving boundaries is a typical example. This paper aims to establish a coupled numerical model for predicting the internal combustion in a launch process.

A two-fluid model is used to predict the fluid field induced by the propellant combustion. The moving boundary is located by using a finite element method. Based on a user subroutine interface in the commercial software ABAQUS, the development of the fluid field and the mechanical interactions is coupled with each other.

The paper is devoted to provide a coupled computational framework for predicting the propellant combustion in an expanding chamber. The coupling strategy is validated through predicting a pressure-driven piston system. Based on the validated computational framework, the two-phase reactive flows in a launch process is studied. The predicted parameters agree well with experimental measurements.

This paper provide a method to address the difficulties in realizing the dynamic interactions between multi-phase reactive flows and mechanical behaviors. The computational framework can be used as a research tool for investigating fluid field in a combustion chamber with moving boundaries.