Family, Gender, Ethnicity, and Pragmatism in Contemporary Diasporic Chinese Entrepreneurship

Entrepreneurship has been an integral part of the long-standing history of Chinese emigration and a central force in diasporic development. This special issue includes six articles and one research report pertaining to contemporary patterns and emergent themes of diasporic Chinese entrepreneurship. As the special issue editor, I highlight the distinctive characteristics of diasporic Chinese entrepreneurship and discuss the significance of considering the interplay of family, gender, ethnicity, and pragmatism in the study of diasporic Chinese entrepreneurship. I then provide an overview of the works included in this introduction.

Pedal equation and Kepler kinematics

Kepler's laws is an appropriate topic which brings out the significance of pedal equation in Physics. There are several articles which obtain the Kepler's laws as a consequence of the conservation and gravitation laws. This can be shown more easily and ingeniously if one uses the pedal equation of an Ellipse. In fact the complete kinematics of a particle in a attractive central force field can be derived from one single pedal form. Though many articles use the pedal equation, only in few the classical procedure (without proof) for obtaining the pedal equation is mentioned. The reason being the classical derivations can sometimes be lengthier and also not simple. In this paper using elementary physics we derive the pedal equation for all conic sections in an unique, short and pedagogical way. Later from the dynamics of a particle in the attractive central force field we deduce the single pedal form, which elegantly describes all the possible trajectories. Also for the purpose of completion we derive the Kepler's laws.

The Digital Past and the Digital Future

This summary chapter outlines the three contributions this book makes to the state of scholarship. First, it revises the memory of technology’s relationship with historical studies, which was not a tangential movement but a central force in an evolving profession. Second, it argues that historians must choose their words more carefully, as “digital” has come to mean too many things. Clear conversations demand a more nuanced vocabulary, which this book provides. Third, this history has shown how important it is to understand regional differences in experience. The story is not the same in Canada as in the United States, or in Britain. Understanding the nuance between national stories is key to a strong profession able to communicate effectively across boundaries in an increasingly globalized world.

Convective pattern formation in a thermally heated rotating annulus with magnetic central force field

<p>The earth, a sphere consisting of several layers like an onion is still up to now not fully understood. Gaining the fundamental knowledge to understand the mystery of global cell formation and large-scale convection in the interior or at the surface e.g. in our atmosphere is still of great interest from a meteorological point of view and of course in geophysics. However, laboratory experiments are still exposed to a significant problem – gravity. Establishing a radial force field e.g. in a sphere or annulus is still overpowered by gravity unless the experiment is carried out in a microgravity environment. Here, we show a potential application of a central force field induced by magnetic forces that acts on a magnetic fluid in a rotating thermally heated annulus to induce thermomagnetic convection and waves that are similar to the baroclinic annulus with the focus to study large scale atmospheric flow fields in a small laboratory system.</p><p> </p><p>Thermomagnetic convection is based on non-isothermal variation of fluid magnetisation induced e.g. by a temperature gradient in the presence of an external magnetic field. After Currie’s law colder magnetic fluid exhibits a larger fluid magnetisation and is therefore attracted to higher magnetic field intensities. This phenomenon is used to induced convection in a thermally heated annulus filled with a magnetisable ferro-magnetic fluid. Here, we study a 2-dimensional numerical problem geometry where the fluid is cooled at the inner and heated at the outer cylinder. The system is forced with an increasing central force field such that colder fluid is attracted towards the outer boundary when a critical threshold is exceeded – the critical magnetic Rayleigh number an equivalent non-dimensional parameter to the classical Rayleigh number for natural convection.</p><p> </p><p>Numerical results are obtained for two different radii ratios (0.35, 0.5). The parametric study included a range of magnetic Rayleigh numbers between 10<sup>3</sup> to 7.5x10<sup>5</sup> to induce a range of thermomagnetic convective cases. In addition, the thermally annulus is rotated at different speeds expressed via the Taylor number ranging from 10<sup>5</sup> to 10<sup>6</sup>. The observed flow fields reveal similar flow structures as seen in the classical baroclinic wave tank but have a different physically interpretation. The observed modes range from mode number 2 to 8 with stable symmetric to oscillatory and chaotic behaviours. The results are summarised in a regime diagram that is spanned in the thermally forcing and rotation speed space. This may be able to classify certain structures that are used to study atmospheric flow fields for different rotation and thermal forcing states e.g. planetary waves.</p>