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<model xmlns="" xmlns:cmeta="" xmlns:dc="" xmlns:rdf="" xmlns:bqs="" xmlns:cellml="" xmlns:dcterms="" xmlns:vCard="" xmlns:ns7="" cmeta:id="MainSystemic" name="MainSystemic">

<documentation xmlns="">
        <title>Lumped-parameter model for the systemic circulation</title>
            <shortaffil>Sheffield University</shortaffil>
      <section id="sec_status">
	 <title>Model Status</title>
           TThis model describes the human cardiovascular dynamics using lumped-parameter modelling, based on the concept of hydraulic-electric analogue. The original model was implemented using C language. Due to the difference of description language and procedural language, some features such as the heart valve dynamics can not be realised effectively, and have to be simplified in the current CellML implementation.</para>
			<para> The current CellML model implementation runs in OpenCell. The results have been validated against the original C implementation as well as those published data in literature.

      <sect1 id="sec_structure">
        <title>Model Structure</title>
The model comprises two main parts: the heart and the systemic loop, as illustrated in the figure below.  The heart is modelled as a two-chambered pump with variable elastance and two heart valves to control the direction of blood flow. The systemic loop is sub-divided into a number of segments, namely: the aortic sinus, artery, arteriole, capillary and vein segments. In each segment, individual components are modelled by representations of the local resistance to blood flow, vessel elasticity and the inertia of the blood.

<informalfigure float="0" id="system_configuration">
    <imagedata fileref="systemic.png"/>
<caption>Schematic of the system configuration of the cardiovascular model</caption>

This model has been derived and used by a number of investigators, but in the context of this series of CellML models it is one of a family that can be obtained by reduction of a more complex model that is published separately.


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<units name="UnitP" units_ref="UnitP"/>
<units name="UnitQ" units_ref="UnitQ"/>

<import xmlns:xlink="" xlink:href="ModelLeftHeart.cellml">
<component component_ref="LeftHeart" name="LEFTHeart"/>

<import xmlns:xlink="" xlink:href="ModelSys.cellml">
<component component_ref="ModelSys" name="Vessel"/>

<component name="environment">
<variable name="t" public_interface="out" units="second"/>

<map_components component_1="environment" component_2="LEFTHeart"/>
<map_variables variable_1="t" variable_2="t"/>

<map_components component_1="environment" component_2="Vessel"/>
<map_variables variable_1="t" variable_2="t"/>

<map_components component_1="LEFTHeart" component_2="Vessel"/>
<map_variables variable_1="Po" variable_2="Pi"/>
<map_variables variable_1="Qo" variable_2="Qi"/>
<map_variables variable_1="Pi" variable_2="Po"/>
<map_variables variable_1="Qi" variable_2="Qo"/>

  <rdf:RDF xmlns:rdf="" xmlns:bqs="" xmlns:dc="" xmlns:dcterms="" xmlns:vCard="">
    <rdf:Description rdf:about="">
      <dc:title>Lumped-parameter model for the systemic circulation</dc:title>
          <rdf:li rdf:parseType="Resource">
            <vCard:N rdf:parseType="Resource">
            <vCard:ORG rdf:parseType="Resource">
              <vCard:Orgname>The University of Sheffield</vCard:Orgname>
          <rdf:li rdf:parseType="Resource">
            <vCard:N rdf:parseType="Resource">
            <vCard:ORG rdf:parseType="Resource">
              <vCard:Orgname>The University of Sheffield</vCard:Orgname>
    <rdf:Description rdf:about="#MainSystemic">
      <bqs:reference rdf:parseType="Resource">
        <dc:subject rdf:parseType="Resource">
              <rdf:li>cardiovascular circulation</rdf:li>