Characteristics of the Romanian Entrepreneurial Prototype

The objective of this paper is to portray the Romanians’ entrepreneurial current prototype, following to their cultural background and entrepreneurial education – as result of the authors’ own research, and compared to previous similar studies. The research methodology includes both secondary and primary research. The landscape of the entrepreneurial activity in Romania is centred on the profile of the Romanian entrepreneur as offered by “The Global Entrepreneurship Monitor”. The results of two studies completed in Romania, based on Hofstede’s model of cultural dimensions, are analyzed too. As primary research, the paper presents the results of the authors’ investigations around two focus groups which were conducted in Romania. Consequently, the Romanian Entrepreneurial Prototype was developed (2008-2009). In this context, the importance of entrepreneurial higher education is highlighted as well. The research results are important for entrepreneurs and business consultants as well as for strategists and education policy makers – aiming at developing entrepreneurship.cultural dimensions; entrepreneurship; entrepreneurial prototype; entrepreneurial profile; entrepreneurial education; Romanian entrepreneurs.

Groupoid symmetry and constraints in general relativity

When the vacuum Einstein equations are cast in the form of hamiltonian evolution equations, the initial data lie in the cotangent bundle of the manifold M\Sigma\ of riemannian metrics on a Cauchy hypersurface \Sigma. As in every lagrangian field theory with symmetries, the initial data must satisfy constraints. But, unlike those of gauge theories, the constraints of general relativity do not arise as momenta of any hamiltonian group action. In this paper, we show that the bracket relations among the constraints of general relativity are identical to the bracket relations in the Lie algebroid of a groupoid consisting of diffeomorphisms between space-like hypersurfaces in spacetimes. A direct connection is still missing between the constraints themselves, whose definition is closely related to the Einstein equations, and our groupoid, in which the Einstein equations play no role at all. We discuss some of the difficulties involved in making such a connection.Comment: 22 pages, major revisio

Ising magnetism and ferroelectricity in Ca3_3CoMnO6_6

The origin of both the Ising chain magnetism and ferroelectricity in Ca$_3$CoMnO$_6$ is studied by $ab$ $initio$ electronic structure calculations and x-ray absorption spectroscopy. We find that Ca$_3$CoMnO$_6$ has the alternate trigonal prismatic Co$^{2+}$ and octahedral Mn$^{4+}$ sites in the spin chain. Both the Co$^{2+}$ and Mn$^{4+}$ are in the high spin state. In addition, the Co$^{2+}$ has a huge orbital moment of 1.7 $\mu_B$ which is responsible for the significant Ising magnetism. The centrosymmetric crystal structure known so far is calculated to be unstable with respect to exchange striction in the experimentally observed $\uparrow\uparrow\downarrow\downarrow$ antiferromagnetic structure for the Ising chain. The calculated inequivalence of the Co-Mn distances accounts for the ferroelectricity.Comment: 4 pages, 3 figures, PRL in press (changes made upon referees comments

NUMERICAL AND EXPERIMENTAL STEADY STATE FLOW AND HEAT TRANSFER IN A CONTINUOUS SPOUTED BED

Experimental measurements on heat transfer and flow properties and CFD simulations based on the two-fluid model (Eulerian-Eulerian approach) were performed in a draft tube continuous spouted bed system. The simulated results on the gas-particle flow patterns and the temperature distribution in the bed agreed well with our experimental data

NUMERICAL AND EXPERIMENTAL STEADY STATE FLOW AND HEAT TRANSFER IN A CONTINUOUS SPOUTED BED

Experimental measurements on heat transfer and flow properties and CFD simulations based on the two-fluid model (Eulerian-Eulerian approach) were performed in a draft tube continuous spouted bed system. The simulated results on the gas-particle flow patterns and the temperature distribution in the bed agreed well with our experimental data

Experimental and theoretical evidences for the ice regime in planar artificial spin ices

In this work, we explore a kind of geometrical effect in the thermodynamics of artificial spin ices (ASI). In general, such artificial materials are athermal. Here, We demonstrate that geometrically driven dynamics in ASI can open up the panorama of exploring distinct ground states and thermally magnetic monopole excitations. It is shown that a particular ASI lattice will provide a richer thermodynamics with nanomagnet spins experiencing less restriction to flip precisely in a kind of rhombic lattice. This can be observed by analysis of only three types of rectangular artificial spin ices (RASI). Denoting the horizontal and vertical lattice spacings by a and b, respectively, then, a RASI material can be described by its aspect ratio $\gamma$=a/b. The rhombic lattice emerges when $\gamma$=$\sqrt{3}$. So, by comparing the impact of thermal effects on the spin flips in these three appropriate different RASI arrays, it is possible to find a system very close to the ice regime