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Strategic Integration of IT and Business Service Management
BMC Software, Inc., a leading global provider of enterprise management solutions helps companies to automate their Information Technology (IT) and align it to the needs of the business, pioneered the concept of Business Service Management (BSM). This case investigates how BMC provides products and services to help IT organizations incorporate Information Technology Service Management (ITSM) and BSM into business processes. The implementation of this strategy has made BMC a leader in BSM solutions. As a result of its business strategy, between 2002 and 2007, BMC revenue increased from 1,580 (in millions); stock value increased from 36.92
Theory of pattern-formation of metallic microparticles in poorly conducting liquid
We develop continuum theory of self-assembly and pattern formation in
metallic microparticles immersed in a poorly conducting liquid in DC electric
field. The theory is formulated in terms of two conservation laws for the
densities of immobile particles (precipitate) and bouncing particles (gas)
coupled to the Navier-Stokes equation for the liquid. This theory successfully
reproduces correct topology of the phase diagram and primary patterns observed
in the experiment [Sapozhnikov et al, Phys. Rev. Lett. v. 90, 114301 (2003)]:
static crystals and honeycombs and dynamic pulsating rings and rotating
multi-petal vortices.Comment: 4 pages, 5 figures, submitted to Phys. Rev. Let
RGB generation by four-wave mixing in small-core holey fibers
We report the generation of white light comprising red, green, and blue spectral bands from a frequency-doubled fiber laser by an efficient four-wave mixing process in submicron-sized cores of microstructured holey fibers. A master-oscillator power amplifier (MOPA) source based on Yb-doped fiber is employed to generate 80 ps pulses at 1060 nm wavelength with 32 MHz repetition rate, which are then frequency-doubled in an LBO crystal to generate up to 2 W average power of green light. The green pump is then carefully launched into secondary cores of the cladding of photonic bandgap fibers. These secondary cores with diameters of about 400 to 800 nm act as highly nonlinear waveguides. At the output, we observe strong red and blue sidebands which, together with the remaining green pump light, form a visible white light source of about 360 mW. The generating process is identified as four-wave mixing where phase matching is achieved by birefringence in the secondary cores which arises from non-symmetric deformation during the fiber fabrication. Numerical models of the fiber structure and of the nonlinear processes confirm our interpretation. Finally, we discuss power scaling and limitations of the white light source due to the damage threshold of silica fibers
Significance of low energy impact damage on modal parameters of composite beams by design of experiments
This paper presents an experimental study on the effects of multi-site damage on the vibration response of composite beams damaged by low energy impacts around the barely visible impact damage limit (BVID). The variation of the modal parameters with different levels of impact energy and density of damage is studied. Vibration tests have been carried out with both burst random and classical sine dwell excitations in order to compare that which of the methods among Polymax and Half Bandwidth Method is more suitable for damping estimation in the presence of damage. Design of experiments (DOE) performed on the experimental data show that natural frequency is a more sensitive parameter for damage detection than the damping ratio. It also highlighted energy of impact as the factor having a more significant effect on the modal parameters. Half Bandwidth Method is found to be unsuitable for damping estimation in the presence of damage
On the emergent Semantic Web and overlooked issues
The emergent Semantic Web, despite being in its infancy, has already received a lotof attention from academia and industry. This resulted in an abundance of prototype systems and discussion most of which are centred around the underlying infrastructure. However, when we critically review the work done to date we realise that there is little discussion with respect to the vision of the Semantic Web. In particular, there is an observed dearth of discussion on how to deliver knowledge sharing in an environment such as the Semantic Web in effective and efficient manners. There are a lot of overlooked issues, associated with agents and trust to hidden assumptions made with respect to knowledge representation and robust reasoning in a distributed environment. These issues could potentially hinder further development if not considered at the early stages of designing Semantic Web systems. In this perspectives paper, we aim to help engineers and practitioners of the Semantic Web by raising awareness of these issues
Reaction Diffusion and Ballistic Annihilation Near an Impenetrable Boundary
The behavior of the single-species reaction process is examined
near an impenetrable boundary, representing the flask containing the reactants.
Two types of dynamics are considered for the reactants: diffusive and ballistic
propagation. It is shown that the effect of the boundary is quite different in
both cases: diffusion-reaction leads to a density excess, whereas ballistic
annihilation exhibits a density deficit, and in both cases the effect is not
localized at the boundary but penetrates into the system. The field-theoretic
renormalization group is used to obtain the universal properties of the density
excess in two dimensions and below for the reaction-diffusion system. In one
dimension the excess decays with the same exponent as the bulk and is found by
an exact solution. In two dimensions the excess is marginally less relevant
than the bulk decay and the density profile is again found exactly for late
times from the RG-improved field theory. The results obtained for the diffusive
case are relevant for Mg or Cd doping in the TMMC crystal's
exciton coalescence process and also imply a surprising result for the dynamic
magnetization in the critical one-dimensional Ising model with a fixed spin.
For the case of ballistic reactants, a model is introduced and solved exactly
in one dimension. The density-deficit profile is obtained, as is the density of
left and right moving reactants near the impenetrable boundary.Comment: to appear in J. Phys.
Statistical Physics of Irregular Low-Density Parity-Check Codes
Low-density parity-check codes with irregular constructions have been
recently shown to outperform the most advanced error-correcting codes to date.
In this paper we apply methods of statistical physics to study the typical
properties of simple irregular codes.
We use the replica method to find a phase transition which coincides with
Shannon's coding bound when appropriate parameters are chosen.
The decoding by belief propagation is also studied using statistical physics
arguments; the theoretical solutions obtained are in good agreement with
simulations. We compare the performance of irregular with that of regular codes
and discuss the factors that contribute to the improvement in performance.Comment: 20 pages, 9 figures, revised version submitted to JP
Thermodynamic properties of a small superconducting grain
The reduced BCS Hamiltonian for a metallic grain with a finite number of
electrons is considered. The crossover between the ultrasmall regime, in which
the level spacing, , is larger than the bulk superconducting gap, ,
and the small regime, where , is investigated analytically
and numerically. The condensation energy, spin magnetization and tunneling peak
spectrum are calculated analytically in the ultrasmall regime, using an
approximation controlled by as small parameter, where is the
number of interacting electron pairs. The condensation energy in this regime is
perturbative in the coupling constant , and is proportional to . We find that also in a large regime with
, in which pairing correlations are already rather well developed,
the perturbative part of the condensation energy is larger than the singular,
BCS, part. The condition for the condensation energy to be well approximated by
the BCS result is found to be roughly . We show how
the condensation energy can, in principle, be extracted from a measurement of
the spin magnetization curve, and find a re-entrant susceptibility at zero
temperature as a function of magnetic field, which can serve as a sensitive
probe for the existence of superconducting correlations in ultrasmall grains.
Numerical results are presented which suggest that in the large limit the
1/N correction to the BCS result for the condensation energy is larger than
.Comment: 17 pages, 7 figures, Submitted to Phys. Rev.
Assessing students' experiences of teaching-learning environments and approaches to learning.:Validation of a questionnaire used in different countries and varying contexts.
Determining the Magnetic Field Orientation of Coronal Mass Ejections from Faraday Rotation
We describe a method to measure the magnetic field orientation of coronal
mass ejections (CMEs) using Faraday rotation (FR). Two basic FR profiles,
Gaussian-shaped with a single polarity or "N"-like with polarity reversals, are
produced by a radio source occulted by a moving flux rope depending on its
orientation. These curves are consistent with the Helios observations,
providing evidence for the flux-rope geometry of CMEs. Many background radio
sources can map CMEs in FR onto the sky. We demonstrate with a simple flux rope
that the magnetic field orientation and helicity of the flux rope can be
determined 2-3 days before it reaches Earth, which is of crucial importance for
space weather forecasting. An FR calculation based on global
magnetohydrodynamic (MHD) simulations of CMEs in a background heliosphere shows
that FR mapping can also resolve a CME geometry curved back to the Sun. We
discuss implementation of the method using data from the Mileura Widefield
Array (MWA).Comment: 22 pages with 9 figures, accepted for publication in Astrophys.
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