Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A State of Art Review on Wireless Power Transmission Approaches for
  Implantable Medical Devices   Wireless power transmission (WPT) is a critical technology that provides a
secure alternative mechanism for wireless power and communication with
implantable medical devices. WPT approaches for implantable medical devices
have been utilized based on applications. For instance, the inductive coupling
tactic is mostly employed for transmission of energy to neuro-stimulators, and
the ultrasonic method is used for deep-seated implants. This article provides a
study concentrating on popular WPT techniques for implantable medical devices
(IMDs) including inductive coupling, microwave, ultrasound, and hybrid WPT
systems consisting of two approaches combined. Moreover, an overview of the
major works is analyzed with a comparison of their major design elements,
operating frequency, distance, efficiency, and harvested power.

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The categories of this paper are: adap-org
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The categories of this paper are: stat
5
The categories of this paper are: gr-qc
1
The categories of this paper are: cs
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The categories of this paper are: acc-phys
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The categories of this paper are: astro-ph
3
The categories of this paper are: physics
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The categories of this paper are: dg-ga
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The categories of this paper are: patt-sol
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The categories of this paper are: ao-sci
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The categories of this paper are: q-alg
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The categories of this paper are: chem-ph
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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: quant-ph
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The categories of this paper are: mtrl-th