4,710 research outputs found
Measuring Employee Turnover in Australian Pig Production
Limited availability of competent and motivated staff has been repeatedly cited as one of the major constraints on pig production in Australia. Whilst a considerable effort is put into training staff (Western Australia boasts the most advanced training facility in South-East Asia), practically nothing is known about the rates of employee turnover. Based on a postal survey and case studies of high and low turnover piggeries, this paper provides the first objective measures of staff turnover in the pig industry and explores possible explanatory factors. Measurement of turnover can provide managers with a benchmark to assess their own performance. This study also revealed shortcomings in the standard Separation Method used by the Australian Bureau of Statistics when it is applied to relatively small businesses. Alternative measures were calculated and are discussed.Farm Management,
On algebraic structures in supersymmetric principal chiral model
Using the Poisson current algebra of the supersymmetric principal chiral
model, we develop the algebraic canonical structure of the model by evaluating
the fundamental Poisson bracket of the Lax matrices that fits into the rs
matrix formalism of non-ultralocal integrable models. The fundamental Poisson
bracket has been used to compute the Poisson bracket algebra of the monodromy
matrix that gives the conserved quantities in involution
New approaches to Spanish anarchism
© 2016 Intellect Ltd Introduction. This article introduces the themes of this special edition, presenting the case that the history of Spanish anarchism needs to be situated within a broader, international history of the left. This view helps to disrupt the image of anarchism as 'exceptional', without losing sight of its specific manifestation in Spain. It proceeds to outline the five articles that make up the remainder of the edition
Auxiliary Fields for Super Yang-Mills from Division Algebras
Division algebras are used to explain the existence and symmetries of various
sets of auxiliary fields for super Yang-Mills in dimensions .
(Contribution to G\"ursey Memorial Conference I: Strings and Symmetries)Comment: 7 pages, plain TeX, CERN-TH.7470/9
A homomorphism theorem and a Trotter product formula for quantum stochastic flows with unbounded coefficients
We give a new method for proving the homomorphic property of a quantum
stochastic ow satisfying a quantum stochastic differential equation with
unbounded coefficients, under some further hypotheses. As an application, we
prove a Trotter product formula for quantum stochastic ows and obtain quantum
stochastic dilations of a class of quantum dynamical semigroups generalizing
results of [5
Density profiles of a colloidal liquid at a wall under shear flow
Using a dynamical density functional theory we analyze the density profile of
a colloidal liquid near a wall under shear flow. Due to the symmetries of the
system considered, the naive application of dynamical density functional theory
does not lead to a shear induced modification of the equilibrium density
profile, which would be expected on physical grounds. By introducing a
physically motivated dynamic mean field correction we incorporate the missing
shear induced interparticle forces into the theory. We find that the shear flow
tends to enhance the oscillations in the density profile of hard-spheres at a
hard-wall and, at sufficiently high shear rates, induces a nonequilibrium
transition to a steady state characterized by planes of particles parallel to
the wall. Under gravity, we find that the center-of-mass of the density
distribution increases with shear rate, i.e., shear increases the potential
energy of the particles
Real Forms of Non-abelian Toda Theories and their W-algebras
We consider real forms of Lie algebras and embeddings of sl(2) which are
consistent with the construction of integrable models via Hamiltonian
reduction. In other words: we examine possible non-standard reality conditions
for non-abelian Toda theories. We point out in particular that the usual
restriction to the maximally non-compact form of the algebra is unnecessary,
and we show how relaxing this condition can lead to new real forms of the
resulting W-algebras. Previous results for abelian Toda theories are recovered
as special cases. The construction can be extended straightforwardly to deal
with osp(1|2) embeddings in Lie superalgebras. Two examples are worked out in
detail, one based on a bosonic Lie algebra, the other based on a Lie
superalgebra leading to an action which realizes the N=4 superconformal
algebra.Comment: 11 pages, LaTex; minor errors corrected, extra references adde
On the Classification of Real Forms of Non-Abelian Toda Theories and W-algebras
We consider conformal non-Abelian Toda theories obtained by hamiltonian
reduction from Wess-Zumino-Witten models based on general real Lie groups. We
study in detail the possible choices of reality conditions which can be imposed
on the WZW or Toda fields and prove correspondences with sl(2,R) embeddings
into real Lie algebras and with the possible real forms of the associated
W-algebras. We devise a a method for finding all real embeddings which can be
obtained from a given embedding of sl(2,C) into a complex Lie algebra. We then
apply this to give a complete classification of real embeddings which are
principal in some simple regular subalgebra of a classical Lie algebra.Comment: 42 pages, LaTeX; Minor corrections to ensure consistent conventions;
some references adde
Conserved charges and supersymmetry in principal chiral and WZW models
Conserved and commuting charges are investigated in both bosonic and
supersymmetric classical chiral models, with and without Wess-Zumino terms. In
the bosonic theories, there are conserved currents based on symmetric invariant
tensors of the underlying algebra, and the construction of infinitely many
commuting charges, with spins equal to the exponents of the algebra modulo its
Coxeter number, can be carried out irrespective of the coefficient of the
Wess-Zumino term. In the supersymmetric models, a different pattern of
conserved quantities emerges, based on antisymmetric invariant tensors. The
current algebra is much more complicated than in the bosonic case, and it is
analysed in some detail. Two families of commuting charges can be constructed,
each with finitely many members whose spins are exactly the exponents of the
algebra (with no repetition modulo the Coxeter number). The conserved
quantities in the bosonic and supersymmetric theories are only indirectly
related, except for the special case of the WZW model and its supersymmetric
extension.Comment: LaTeX; 49 pages; v2: minor changes and additions to text and ref
Higher-spin conserved currents in supersymmetric sigma models on symmetric spaces
Local higher-spin conserved currents are constructed in the supersymmetric
sigma models with target manifolds symmetric spaces . One class of
currents is based on generators of the de Rham cohomology ring of ; a
second class of currents are higher-spin generalizations of the
(super)energy-momentum tensor. A comprehensive analysis of the invariant
tensors required to construct these currents is given from two complimentary
points of view, and sets of primitive currents are identified from which all
others can be constructed as differential polynomials. The Poisson bracket
algebra of the top component charges of the primitive currents is calculated.
It is shown that one can choose the primitive currents so that the bosonic
charges all Poisson-commute, while the fermionic charges obey an algebra which
is a form of higher-spin generalization of supersymmetry. Brief comments are
made on some implications for the quantized theories.Comment: 40 pages; LaTe
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