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The purpose of the present study is to develop a new numerical framework that can predict the supersonic base flow more accurately, including the development of axisymmetrically separated shear layer and recompression shock. To this end, two aspects are improved and combined, i.e. a newly self-adaptive turbulence eddy simulation (SATES) turbulence modeling method and a high-order discretization numerical scheme. Furthermore, the performance of the new numerical framework within a general-purpose PHengLEI software is assessed in detail.

Satisfactory prediction of the supersonic separated shear layer with unsteady wake flow is quite challenging. By using a unified turbulence model called SATES combining high-order accurate discretization numerical schemes, the present study first assesses the performance of newly developed SATES for supersonic axisymmetric separation flows. A high-order finite differencing-based compressible computational fluid dynamics (CFD) code called PHengLEI is developed and several different numerical schemes are used to investigate the effects on shock-turbulence interactions, which include the monotonic upstream-centered scheme for conservation laws (MUSCL), weighted compact nonlinear scheme (WCNS) and hybrid cell-edge and cell-node dissipative compact scheme (HDCS).

Compared with the available experimental data and the numerical predictions, the results of SATES by using high-order accurate WCNS or HDCS schemes agree better with the experiments than the results by using the MUSCL scheme. The WCNS and HDCS can also significantly improve the prediction of flow physics in terms of the instability of the annular shear layer and the evolution of the turbulent wake.

The small deviations in the recirculation region can be found between the present numerical results and experimental data, which could be caused by the inaccurate incoming boundary layer condition and compressible effects. Therefore, a proper incoming boundary layer condition with turbulent fluctuations and compressibility effects need to be considered to further improve the accuracy of simulations.

The present study evaluates a high-order discretization-based SATES turbulence model for supersonic separation flows, which is quite valuable for improving the calculation accuracy of aeronautics applications, especially in supersonic conditions.

For the first time, the newly developed SATES turbulence modeling method combining the high-order accurate WCNS or HDCS numerical schemes is implemented on the PHengLEI software and successfully applied for the simulations of supersonic separation flows, and satisfactory results are obtained. The unsteady evolutions of the supersonic annular shear layer are analyzed, and the hairpin vortex structures are found in the simulation.

The purpose of this paper is to explore the potential regional preferences of the diaspora and explain how such preferences affect their decision when engaging in reverse Foreign Direct Investment (FDI). Since diasporas often act as conduits for trade and investment, the author is interested in whether these regional preferences affect their choice of destination for FDI.

The author developed and pre-tested a questionnaire that was administered in pen and paper as well as online. Totally, 158 professional, managers and entrepreneurs with Indian diasporic background in the USA and Canada participated in the study. Follow-up interviews were conducted with 25 participants.

Participants indicated that they did not favor their region of origin over the entire country. However, most of the participants only invested in their region of origin.

Interviews were based on the original survey questionnaire and did not further probe other issues. The current study should be treated as exploratory in nature and the results should be used as a springboard for future research.

It would seem that the region of origin was important in the decision to migrate and for reverse FDI, even though cognitively the participants did not recognize it to the same extent. This might point to a mediation effect, which should be investigated in future studies. This paper helps businesses and governments understand the extent to which sub-national regional ties explain the investment motivations of people investing back in their home countries.

Furthermore, the importance of regional ties in the decisions to both invest and migrate point to the importance of studying sub-national cultural and institutional issues rather than treating large multicultural countries such as India as a monolithic bloc.

The author used network ties theories to investigate and explain the investment behavior of Indian diaspora. While other disciplines (e.g. geography, sociology and economics) might have studied similar phenomena, the author looked and expanded the knowledge from a management perspective.

The purpose of this article was to discuss the phenomenon of international talent mobility and competition in relation to China's engagement in the “talent war” for attracting, retaining and managing global talents, from a policy perspective.

The author adopts an approach combining literature review and international comparative analysis.

Factors explaining global talent mobility have been predominantly economic. This paper argues that China should also focus on other critical non-economic aspects for attracting and retaining talents in the long-term. The Chinese Government may learn from the experience of other competing countries in developing a national strategy for attracting and retaining global talents. While China has an advantage in attracting overseas Chinese who are attached to its cultural roots and are other competing countries' residents or citizens, its existing talent policy may not be able to create effective local and institutional environment in attracting and retaining needed talents.

An attractive policy is key to winning the global talent war and determining the future development path of a nation. The talent policy at a national level should address not only economic factors but also personal, professional and institutional factors.

Winning the global talent war is a policy competition among countries. The Chinese Government may succeed in the war for talent by adopting a multi-pronged, multi-level and long-term talent strategy. This paper calls for China to reconsider its recent reform on permanent residence (green card) policy reform from a global talent competition perspective.