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Organizing otherwise: translating anarchism in a voluntary sector organization
Although foundational texts in Critical Management Studies (CMS) pointed to the empirical significance of anarchism as an inspiration for alternative ways of organizing (Burrell, 1992), relatively little work of substance has been undertaken within CMS to explore how anarchists organize or how anarchist principles of organization might fare in other contexts. This paper addresses this gap by reporting on the experiences of a UK Voluntary Sector Organization (VSO) seeking to adopt non-hierarchical working practices inspired by anarchism. The paper analyses this process of organizational change by examining how ideas and practices are translated and transformed as they travel from one context (direct action anarchism) to another (the voluntary sector). Whilst the onset of austerity and funding cuts created the conditions of possibility for this change, it was the discursive translation of 'anarchism' into 'non-hierarchical organizing' that enabled these ideas to take hold. The concept of 'non-hierarchical' organization constituted an open space that was defined by negation and therefore capable of containing a multiplicity of meanings. Rather than having to explicitly embrace anarchism, members were able to find common ground on what they did not want (hierarchy) and create a discursive space for democratically determining what might replace it
Constructive counterexamples to additivity of minimum output R\'enyi entropy of quantum channels for all p>2
We present a constructive example of violation of additivity of minimum
output R\'enyi entropy for each p>2. The example is provided by antisymmetric
subspace of a suitable dimension. We discuss possibility of extension of the
result to go beyond p>2 and obtain additivity for p=0 for a class of
entanglement breaking channels.Comment: 4 pages; a reference adde
Maximization of capacity and p-norms for some product channels
It is conjectured that the Holevo capacity of a product channel \Omega
\otimes \Phi is achieved when product states are used as input. Amosov, Holevo
and Werner have also conjectured that the maximal p-norm of a product channel
is achieved with product input states. In this paper we establish both of these
conjectures in the case that \Omega is arbitrary and \Phi is a CQ or QC channel
(as defined by Holevo). We also establish the Amosov, Holevo and Werner
conjecture when \Omega is arbitrary and either \Phi is a qubit channel and p=2,
or \Phi is a unital qubit channel and p is integer. Our proofs involve a new
conjecture for the norm of an output state of the half-noisy channel I \otimes
\Phi, when \Phi is a qubit channel. We show that this conjecture in some cases
also implies additivity of the Holevo capacity
The Hopf Algebra Structure of the Character Rings of Classical Groups
The character ring \CGL of covariant irreducible tensor representations of
the general linear group admits a Hopf algebra structure isomorphic to the Hopf
algebra \Sym$ of symmetric functions. Here we study the character rings \CO and
\CSp of the orthogonal and symplectic subgroups of the general linear group
within the same framework of symmetric functions. We show that \CO and \CSp
also admit natural Hopf algebra structures that are isomorphic to that of \CGL,
and hence to \Sym. The isomorphisms are determined explicitly, along with the
specification of standard bases for \CO and \CSp analogous to those used for
\Sym. A major structural change arising from the adoption of these bases is the
introduction of new orthogonal and symplectic Schur-Hall scalar products.
Significantly, the adjoint with respect to multiplication no longer coincides,
as it does in the \CGL case, with a Foulkes derivative or skew operation. The
adjoint and Foulkes derivative now require separate definitions, and their
properties are explored here in the orthogonal and symplectic cases. Moreover,
the Hopf algebras \CO and \CSp are not self-dual. The dual Hopf algebras \CO^*
and \CSp^* are identified. Finally, the Hopf algebra of the universal rational
character ring \CGLrat of mixed irreducible tensor representations of the
general linear group is introduced and its structure maps identified.Comment: 38 pages, uses pstricks; new version is a major update, new title,
new material on rational character
Plethystic Vertex Operators and Boson-Fermion Correspondences
We study the algebraic properties of plethystic vertex operators, introduced
in J. Phys. A: Math. Theor. 43 405202 (2010), underlying the structure of
symmetric functions associated with certain generalized universal character
rings of subgroups of the general linear group, defined to stabilize tensors of
Young symmetry type characterized by a partition of arbitrary shape \pi. Here
we establish an extension of the well-known boson-fermion correspondence
involving Schur functions and their associated (Bernstein) vertex operators:
for each \pi, the modes generated by the plethystic vertex operators and their
suitably constructed duals, satisfy the anticommutation relations of a complex
Clifford algebra. The combinatorial manipulations underlying the results
involve exchange identities exploiting the Hopf-algebraic structure of certain
symmetric function series and their plethysms.Comment: 21 pages, LaTeX. Minor typos corrected. Added brief survey of related
work and new reference
Hopf algebras and characters of classical groups
Schur functions provide an integral basis of the ring of symmetric functions.
It is shown that this ring has a natural Hopf algebra structure by identifying
the appropriate product, coproduct, unit, counit and antipode, and their
properties. Characters of covariant tensor irreducible representations of the
classical groups GL(n), O(n) and Sp(n) are then expressed in terms of Schur
functions, and the Hopf algebra is exploited in the determination of
group-subgroup branching rules and the decomposition of tensor products. The
analysis is carried out in terms of n-independent universal characters. The
corresponding rings, CharGL, CharO and CharSp, of universal characters each
have their own natural Hopf algebra structure. The appropriate product,
coproduct, unit, counit and antipode are identified in each case.Comment: 9 pages. Uses jpconf.cls and jpconf11.clo. Presented by RCK at
SSPCM'07, Myczkowce, Poland, Sept 200
Saturated laser fluorescence in turbulent sooting flames at high pressure
The primary objective was to develop a quantitative, single pulse, laser-saturated fluorescence (LSF) technique for measurement of radical species concentrations in practical flames. The species of immediate interest was the hydroxyl radical. Measurements were made in both turbulent premixed diffusion flames at pressures between 1 and 20 atm. Interferences from Mie scattering were assessed by doping with particles or by controlling soot loading through variation of equivalence ratio and fuel type. The efficacy of the LSF method at high pressure was addressed by comparing fluorescence and adsorption measurements in a premixed, laminar flat flame at 1-20 atm. Signal-averaging over many laser shots is sufficient to determine the local concentration of radical species in laminar flames. However, for turbulent flames, single pulse measurements are more appropriate since a statistically significant number of laser pulses is needed to determine the probability function (PDF). PDFs can be analyzed to give true average properties and true local kinetics in turbulent, chemically reactive flows
Electricity load profile classification using Fuzzy C-Means method
This paper presents the Fuzzy C-Means (FCM) clustering method. The FCM technique assigns a degree of membership for each data set to several clusters, thus offering the opportunity to deal with load profiles that could belong to more than one group at the same time. The FCM algorithm is based on minimising a c-means objective function to determine an optimal classification. The simulation of FCM was carried out using actual sample data from Indonesia and the results are presented. Some validity index measurements was carried out to estimate the compactness of the resulting clusters or to find the optimal number of clusters for a data set
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