Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A Sufficient Condition for Power Flow Insolvability with Applications to
  Voltage Stability Margins   For the nonlinear power flow problem specified with standard PQ, PV, and
slack bus equality constraints, we present a sufficient condition under which
the specified set of nonlinear algebraic equations has no solution. This
sufficient condition is constructed in a framework of an associated feasible,
convex optimization problem. The objective employed in this optimization
problem yields a measure of distance (in a parameter set) to the power flow
solution boundary. In practical terms, this distance is closely related to
quantities that previous authors have proposed as voltage stability margins. A
typical margin is expressed in terms of the parameters of system loading
(injected powers); here we additionally introduce a new margin in terms of the
parameters of regulated bus voltages.

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The categories of this paper are: funct-an
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The categories of this paper are: q-fin
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The categories of this paper are: econ
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The categories of this paper are: eess
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The categories of this paper are: comp-gas
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The categories of this paper are: patt-sol
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The categories of this paper are: nucl-th
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The categories of this paper are: dg-ga
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The categories of this paper are: plasm-ph
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The categories of this paper are: astro-ph
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The categories of this paper are: math-ph
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The categories of this paper are: atom-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: physics
10
The categories of this paper are: q-bio
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The categories of this paper are: mtrl-th