264 research outputs found
-dimensional Arrays of Josephson Junctions, Spin Glasses and -deformed Harmonic Oscillators
We study the statistical mechanics of a -dimensional array of Josephson
junctions in presence of a magnetic field. In the high temperature region the
thermodynamical properties can be computed in the limit , where
the problem is simplified; this limit is taken in the framework of the mean
field approximation. Close to the transition point the system behaves very
similar to a particular form of spin glasses, i.e. to gauge glasses. We have
noticed that in this limit the evaluation of the coefficients of the high
temperature expansion may be mapped onto the computation of some matrix
elements for the -deformed harmonic oscillator
Exact Random Walk Distributions using Noncommutative Geometry
Using the results obtained by the non commutative geometry techniques applied
to the Harper equation, we derive the areas distribution of random walks of
length on a two-dimensional square lattice for large , taking into
account finite size contributions.Comment: Latex, 3 pages, 1 figure, to be published in J. Phys. A : Math. Ge
Internationalisation of service firms through corporate social entrepreneurship and networking
Findings: The findings reveal that, by engaging in social entrepreneurship, these MNCs have focused on the neglected needs of the BOP population, developed sustainable solutions and empowerment, and started with social value creation and postponed value capturing. The pursuit of corporate social entrepreneurship has paved the way for them to establish relationships with NGOs. While the MNCs have mainly had the technical knowledge and financial resources required, collaboration with NGOs have allowed them to learn about the BOP’s specific needs and benefit from the NGOs’ knowledge, human resources and good relationships in this market.Originality/value: This research unravels how service firms can seize opportunities at the BOP. The authors build on social entrepreneurship theory and bring new insights to the field of international business. In addition, the authors broaden the network view and show how networking with social actors such as NGOs enables the mobilisation of resources, actors and activities in emerging markets.Design/methodology/approach: This research adopts an exploratory approach employing qualitative multiple case studies. Three service firms that have targeted the BOP markets in India were studied. In total, 25 in-depth interviews were conducted with multinational corporations (MNCs) and their NGO partners. Data analysis was facilitated through pattern matching and systematic case comparison.Purpose: The purpose of this paper is to explore how employing corporate social entrepreneurship and developing a network of relationships with non-governmental organisations (NGOs) can support and contribute towards the internationalisation of service firms into the base of the pyramid (BOP) markets in emerging markets
“Reel”ing it in:The Indian film industry’s survival and growth in the post-pandemic era
Business-to-business (B2B) firms are expected to work collectively to overcome the sector's challenges. The COVID-19 pandemic was a ‘rare’ event that triggered failures across many business sectors. With limited financial resources, governments in emerging economies could not assist businesses and the B2B firms relied on their networks for survival. In this study, we explored the B2B firms' response to the pandemic and whether their long-established networks and relationships with each other aided or hindered their ability to operate through the disruption and rebound in the post-pandemic recovery period. We studied the operations of the Indian film industry through the pandemic and collected interview data from key informants from the sector. Using stakeholder and institutional theory lenses, we highlighted the changes in the sector, including the weakening of B2B firm networks and firms moving away from organizational collaboration to prioritizing individual interests. The nature of the business model has changed, with increased use of digital platforms for movie releases. These findings have implications for theory and practice as international government agencies were providing incentives for Indian filmmakers to produce movies in their country, which needed to be countered by the Indian government
Global talent management and staffing in MNEs: An introduction to the edited volume of international business and management
Extreme events driven glassy behaviour in granular media
Motivated by recent experiments on the approach to jamming of a weakly forced
granular medium using an immersed torsion oscillator [Nature 413 (2001) 407],
we propose a simple model which relates the microscopic dynamics to macroscopic
rearrangements and accounts for the following experimental facts: (1) the
control parameter is the spatial amplitude of the perturbation and not its
reduced peak acceleration; (2) a Vogel-Fulcher-Tammann-like form for the
relaxation time. The model draws a parallel between macroscopic rearrangements
in the system and extreme events whose probability of occurrence (and thus the
typical relaxation time) is estimated using extreme-value statistics. The range
of validity of this description in terms of the control parameter is discussed
as well as the existence of other regimes.Comment: 7 pages, to appear in Europhys. Let
Current Distribution in the Three-Dimensional Random Resistor Network at the Percolation Threshold
We study the multifractal properties of the current distribution of the
three-dimensional random resistor network at the percolation threshold. For
lattices ranging in size from to we measure the second, fourth and
sixth moments of the current distribution, finding {\it e.g.\/} that
where is the conductivity exponent and is the
correlation length exponent.Comment: 10 pages, latex, 8 figures in separate uuencoded fil
Driven interfaces in random media at finite temperature : is there an anomalous zero-velocity phase at small external force ?
The motion of driven interfaces in random media at finite temperature and
small external force is usually described by a linear displacement at large times, where the velocity vanishes according to the
creep formula as for . In this paper,
we question this picture on the specific example of the directed polymer in a
two dimensional random medium. We have recently shown (C. Monthus and T. Garel,
arxiv:0802.2502) that its dynamics for F=0 can be analyzed in terms of a strong
disorder renormalization procedure, where the distribution of renormalized
barriers flows towards some "infinite disorder fixed point". In the present
paper, we obtain that for small , this "infinite disorder fixed point"
becomes a "strong disorder fixed point" with an exponential distribution of
renormalized barriers. The corresponding distribution of trapping times then
only decays as a power-law , where the exponent
vanishes as as . Our
conclusion is that in the small force region , the divergence of
the averaged trapping time induces strong
non-self-averaging effects that invalidate the usual creep formula obtained by
replacing all trapping times by the typical value. We find instead that the
motion is only sub-linearly in time , i.e. the
asymptotic velocity vanishes V=0. This analysis is confirmed by numerical
simulations of a directed polymer with a metric constraint driven in a traps
landscape. We moreover obtain that the roughness exponent, which is governed by
the equilibrium value up to some large scale, becomes equal to
at the largest scales.Comment: v3=final versio
Structure of the superconducting state in a fully frustrated wire network with dice lattice geometry
The superconducting state in a fully frustrated wire network with the dice
lattice geometry is investigated in the vicinity of the transition temperature.
Using Abrikosov's variational procedure, we write the Ginzburg-Landau free
energy functional projected on its unstable supspace as an effective model on
the triangular lattice of sixfold coordinated sites. For this latter model, we
obtain a large class of degenerate equilibrium configurations in one to one
correspondence with those previously constructed for the pure XY model on the
maximally frustrated dice lattice. The entropy of these states is proportional
to the linear size of the system. Finally we show that magnetic interactions
between currents provide a degeneracy lifting mechanism.Comment: The final version (as published in Phys. Rev. B). Substantial
corrections have been made to Sec.
Invariant imbedding theory of mode conversion in inhomogeneous plasmas. II. Mode conversion in cold, magnetized plasmas with perpendicular inhomogeneity
A new version of the invariant imbedding theory for the propagation of
coupled waves in inhomogeneous media is applied to the mode conversion of high
frequency electromagnetic waves into electrostatic modes in cold, magnetized
and stratified plasmas. The cases where the external magnetic field is applied
perpendicularly to the direction of inhomogeneity and the electron density
profile is linear are considered. Extensive and numerically exact results for
the mode conversion coefficients, the reflectances and the wave electric and
magnetic field profiles inside the inhomogeneous plasma are obtained. The
dependences of mode conversion phenomena on the magnitude of the external
magnetic field, the incident angle and the wave frequency are explored in
detail.Comment: 11 figures, to be published in Physics of Plasma
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