20,984 research outputs found
Recommended from our members
Enterprise Risk Management: Review, Critique, and Research Directions
© 2014 Elsevier Ltd. Many regulators, rating agencies, executives and academics have advocated a new approach to risk management: Enterprise Risk Management (ERM). ERM proposes the integrated management of all the risks an organization faces, which inherently requires alignment of risk management with corporate governance and strategy. Academic research on ERM is still in its infancy, with articles largely in accounting and finance journals but rarely in management journals. We argue that ERM offers an important new research domain for management scholars. A critical review of ERM research allows us to identify limitations and gaps that management scholars are best equipped to address. This paper not only identifies how management scholars can contribute to ERM research, but also points out why ERM research (and practice) needs management research for its development
Recommended from our members
Secure communication using dynamic VPN provisioning in an Inter-Cloud environment
Most of the current cloud computing platforms offer Infrastructure as a Service (IaaS) model, which aims to provision basic virtualised computing resources as on-demand and dynamic services. Nevertheless, a single cloud does not have limitless resources to offer to its users, hence the notion of an Inter-Cloud enviroment where a cloud can use the infrastructure resources of other clouds. However, there is no common framework in existence that allows the srevice owners to seamlessly provision even some basic services across multiple cloud service providers, albeit not due to any inherent incompatibility or proprietary nature of the foundation technologies on which these cloud platforms are built. In this paper we present a novel solution which aims to cover a gap in a subsection of this problem domain. Our solution offer a security architecture that enables service owners to provision a dynamic and service-oriented secure virtual private network on top of multiple cloud IaaS providers. It does this by leveraging the scalability, robustness and flexibility of peer- to-peer overlay techniques to eliminate the manual configuration, key management and peer churn problems encountered in setting up the secure communication channels dynamically, between different components of a typical service that is deployed on multiple clouds. We present the implementation details of our solution as well as experimental results carried out on two commercial clouds
Recommended from our members
Dynamic virtual private network provisioning from multiple cloud infrastructure service providers
The Cloud infrastructure service providers currently provision basic virtualized computing resources as on demand and dynamic services but there is no common framework in existence that allows the seamless provisioning of even these basic services across multiple cloud service providers, although this is not due to any inherent incompatibility or proprietary nature of the foundation technologies on which these cloud platforms are built. We present a solution idea which aims to provide a dynamic and service oriented provisioning of secure virtual private networks on top of multiple cloud infrastructure service providers. This solution leverages the benefits of peer to peer overlay networks, i.e., the flexibility and scalability to handle the churn of nodes joining and leaving the VPNs and can adapt the topology of the VPN as per the requirements of the applications utilizing its intercloud secure communication framework
Recommended from our members
Trust Model for Optimized Cloud Services
Cloud computing with its inherent advantages draws attention for business critical applications, but concurrently expects high level of trust in cloud service providers. Reputation-based trust is emerging as a good choice to model trust of cloud service providers based on available evidence. Many existing reputation based systems either ignore or give less importance to uncertainty linked with the evidence. In this paper, we propose an uncertainty model and define our approach to compute opinion for cloud service providers. Using subjective logic operators along with the computed opinion values, we propose mechanisms to calculate the reputation of cloud service providers. We evaluate and compare our proposed model with existing reputation models
Thermal conductivity of graphene in Corbino membrane geometry
Local laser excitation and temperature readout from the intensity ratio of
Stokes to anti-Stokes Raman scattering signals are employed to study the
thermal properties of a large graphene membrane. The concluded value of the
heat conductivity coefficient \kappa ~ 600 W/m \cdot K is smaller than
previously reported but still validates the conclusion that graphene is a very
good thermal conductor.Comment: 4 pages, 3 figure
Discriminating quantum-optical beam-splitter channels with number-diagonal signal states: Applications to quantum reading and target detection
We consider the problem of distinguishing, with minimum probability of error,
two optical beam-splitter channels with unequal complex-valued reflectivities
using general quantum probe states entangled over M signal and M' idler mode
pairs of which the signal modes are bounced off the beam splitter while the
idler modes are retained losslessly. We obtain a lower bound on the output
state fidelity valid for any pure input state. We define number-diagonal signal
(NDS) states to be input states whose density operator in the signal modes is
diagonal in the multimode number basis. For such input states, we derive series
formulas for the optimal error probability, the output state fidelity, and the
Chernoff-type upper bounds on the error probability. For the special cases of
quantum reading of a classical digital memory and target detection (for which
the reflectivities are real valued), we show that for a given input signal
photon probability distribution, the fidelity is minimized by the NDS states
with that distribution and that for a given average total signal energy N_s,
the fidelity is minimized by any multimode Fock state with N_s total signal
photons. For reading of an ideal memory, it is shown that Fock state inputs
minimize the Chernoff bound. For target detection under high-loss conditions, a
no-go result showing the lack of appreciable quantum advantage over coherent
state transmitters is derived. A comparison of the error probability
performance for quantum reading of number state and two-mode squeezed vacuum
state (or EPR state) transmitters relative to coherent state transmitters is
presented for various values of the reflectances. While the nonclassical states
in general perform better than the coherent state, the quantitative performance
gains differ depending on the values of the reflectances.Comment: 12 pages, 7 figures. This closely approximates the published version.
The major change from v2 is that Section IV has been re-organized, with a
no-go result for target detection under high loss conditions highlighted. The
last sentence of the abstract has been deleted to conform to the arXiv word
limit. Please see the PDF for the full abstrac
Changes in the measured image separation of the gravitational lens system, PKS 1830-211
We present eight epochs of 43 GHz, dual-polarisation VLBA observations of the
gravitational lens system PKS 1830-211, made over fourteen weeks. A bright,
compact ``core'' and a faint extended ``jet'' are clearly seen in maps of both
lensed images at all eight epochs.
The relative separation of the radio centroid of the cores (as measured on
the sky) changes by up to 87 micro arcsec between subsequent epochs.
A comparison with the previous 43 GHz VLBA observations (Garrett et al. 1997)
made 8 months earlier show even larger deviations in the separation of up to
201 micro arcsec. The measured changes are most likely produced by changes in
the brightness distribution of the background source, enhanced by the
magnification of the lens. A relative magnification matrix that is applicable
on the milliarcsecond scale has been determined by relating two vectors (the
``core-jet'' separations and the offsets of the polarised and total intensity
emission) in the two lensed images. The determinant of this matrix,
-1.13 +/-0.61, is in good agreement with the measured flux density ratio of
the two images. The matrix predicts that the 10 mas long jet, that is clearly
seen in previous 15 and 8.4 GHz VLBA observations (Garrett et al. 1997,
Guirado et al. 1999), should correspond to a 4 mas long jet trailing to the
south-east of the SW image. The clear non-detection of this trailing jet is a
strong evidence for sub-structure in the lens and may require more realistic
lens models to be invoked, e.g. Nair & Garrett (2000).Comment: 8 pages, 5 figure
- …