2,864 research outputs found
Specifying Multimedia Binding Objects in Z
The current standardisation activity of Open Distributed Processing (ODP) has attempted to incorporate multimedia flows of information into its architecture through the idea of stream interfaces. At present the reference model of ODP (ODP-RM) abstracts from the precise nature of the flows of information. As a consequence of this, the ODPRM only deals with syntactic aspects of stream interfaces and does not require them to satisfy any behavioural considerations. It is shown in this paper how the formal notation Z can be used to reason about these flows of information in a manner that enables behavioural as well as temporal aspects to be considered. The example given to highlight the approach is the ODP concept of a binding object
Standardisation of magnetic nanoparticles in liquid suspension
Suspensions of magnetic nanoparticles offer diverse opportunities for technology innovation, spanning a large number of industry sectors from imaging and actuation based applications in biomedicine and biotechnology, through large-scale environmental remediation uses such as water purification, to engineering-based applications such as position-controlled lubricants and soaps. Continuous advances in their manufacture have produced an ever-growing range of products, each with their own unique properties. At the same time, the characterisation of magnetic nanoparticles is often complex, and expert knowledge is needed to correctly interpret the measurement data. In many cases, the stringent requirements of the end-user technologies dictate that magnetic nanoparticle products should be clearly defined, well characterised, consistent and safe; or to put it another way—standardised. The aims of this document are to outline the concepts and terminology necessary for discussion of magnetic nanoparticles, to examine the current state-of-the-art in characterisation methods necessary for the most prominent applications of magnetic nanoparticle suspensions, to suggest a possible structure for the future development of standardisation within the field, and to identify areas and topics which deserve to be the focus of future work items. We discuss potential roadmaps for the future standardisation of this developing industry, and the likely challenges to be encountered along the way
Transport Coefficients of Gluon Plasma
Transport coefficients of gluon plasma are calculated for a SU(3) pure gauge
model by lattice QCD simulations on and
lattices. Simulations are carried out at a slightly above the deconfinement
transition temperature , where a new state of matter is currently being
pursued in RHIC experiments. Our results show that the ratio of the shear
viscosity to the entropy is less than one and the bulk viscosity is consistent
with zero in the region, .Comment: 10 pages, Late
Equivalence of Several Chern-Simons Matter Models
Not only does Chern-Simons (CS) coupling characterize statistics, but also
spin and scaling dimension of matter fields. We demonstrate spin transmutation
in relativistic CS matter theory, and moreover show equivalence of several
models. We study CS vector model in some details, which provide consistent
check to the assertion of the equivalence.Comment: latex, 7page, IFT-478-UNC/NUP-A-93-15 A version within the length
limit for Phys. Rev. Letts (in press
Note on Gauge Theory on Fuzzy Supersphere
We construct a supermatrix model whose classical background gives
two-dimensional noncommutative supersphere. Quantum fluctuations around it give
the supersymmetric gauge theories on the fuzzy supersphere constructed by
Klimcik. This model has a parameter which can tune masses of the
particles in the model and interpolate various supersymmetric gauge theories on
sphere.Comment: 13 pages, LaTe
Smooth Paths on Three Dimensional Lattice
A particular class of random walks with a spin factor on a three dimensional
cubic lattice is studied. This three dimensional random walk model is a simple
generalization of random walk for the two dimensional Ising model. All critical
diffusion constants and associated critical exponents are calculated. Continuum
field theories such as Klein-Gordon, Dirac and massive Chern-Simons theories
are constructed near several critical points.Comment: 7 pages,NUP-A-94-
Scaling Behaviors of Branched Polymers
We study the thermodynamic behavior of branched polymers. We first study
random walks in order to clarify the thermodynamic relation between the
canonical ensemble and the grand canonical ensemble. We then show that
correlation functions for branched polymers are given by those for
theory with a single mass insertion, not those for the theory
themselves. In particular, the two-point function behaves as , not as
, in the scaling region. This behavior is consistent with the fact that
the Hausdorff dimension of the branched polymer is four.Comment: 17 pages, 3 figure
Ginsparg-Wilson Relation, Topological Invariants and Finite Noncommutative Geometry
We show that the Ginsparg-Wilson (GW) relation can play an important role to
define chiral structures in {\it finite} noncommutative geometries. Employing
GW relation, we can prove the index theorem and construct topological
invariants even if the system has only finite degrees of freedom. As an
example, we consider a gauge theory on a fuzzy two-sphere and give an explicit
construction of a noncommutative analog of the GW relation, chirality operator
and the index theorem. The topological invariant is shown to coincide with the
1st Chern class in the commutative limit.Comment: Revtex4 file, 5 pages, references added, typo corrected, the final
version to appear in Phys.Rev.
Noise control by sonic crystal barriers made of recycled materials
A systematic study of noise barriers based on sonic crystals made of
cylinders that use recycled materials like absorbing component is here
reported. The barriers consist of only three rows of perforated metal shells
filled with rubber crumb. Measurements of reflectance and transmittance by
these barriers are reported. Their attenuation properties result from a
combination of sound absorption by the rubber crumb and reflection by the
periodic distribution of scatterers. It is concluded that porous cylinders can
be used as building blocks whose physical parameters can be optimized in order
to design efficient barriers adapted to different noisy environments
Gauge Theory on Noncommutative Supersphere from Supermatrix Model
We construct a supermatrix model which has a classical solution representing
the noncommutative (fuzzy) two-supersphere. Expanding supermatrices around the
classical background, we obtain a gauge theory on a noncommutative superspace
on sphere. This theory has supersymmetry and gauge
symmetry. We also discuss a commutative limit of the model keeping radius of
the supersphere fixed.Comment: 16 pages, Latex, typos corrected, references adde
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