Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Optimal Strokes of Low Reynolds Number Linked-Sphere Swimmers   Optimal gait design is important for micro-organisms and micro-robots that
propel themselves in a fluid environment in the absence of external force or
torque. The simplest models of shape changes are those that comprise a series
of linked-spheres that can change their separation and their sizes. We examine
the dynamics of three existing linked-sphere types of modeling swimmers in low
Reynolds number Newtonian fluids using asymptotic analysis, and obtain their
optimal swimming strokes by solving the Euler-Lagrange equation using the
shooting method. The numerical results reveal that (1) with the minimal 2
degrees of freedom in shape deformations, the model swimmer adopting the mixed
shape deformation modes strategy is more efficient than those with a
single-mode of shape deformation modes, and (2) the swimming efficiency mostly
decreases as the number of spheres increases, indicating that more degrees of
freedom in shape deformations might not be a good strategy in optimal gait
design in low Reynolds number locomotion.

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The categories of this paper are: nucl-th
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The categories of this paper are: cmp-lg
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The categories of this paper are: funct-an
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The categories of this paper are: comp-gas
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The categories of this paper are: hep-lat
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The categories of this paper are: math
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The categories of this paper are: mtrl-th
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The categories of this paper are: plasm-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: quant-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: gr-qc
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The categories of this paper are: alg-geom
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The categories of this paper are: q-bio
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The categories of this paper are: adap-org
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The categories of this paper are: solv-int