A BDDC Preconditioner for the Rotated <svg     style="vertical-align:-4.32007pt;width:25.5px;" id="M1" height="20.450001" version="1.1" viewBox="0 0 25.5 20.450001" width="25.5"  xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg">
	
		
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			<g transform="matrix(.016,-0,0,-.016,17.275,20.388)"><path id="x31" d="M384 0h-275v27q67 5 81.5 18.5t14.5 68.5v385q0 38 -7.5 47.5t-40.5 10.5l-48 2v24q85 15 178 52v-521q0 -55 14.5 -68.5t82.5 -18.5v-27z" /></g>

		
	
</svg> FEM for Elliptic Problems with Discontinuous Coefficients

<table>Plot of the condition numbers as the function of <svg height="20.2125" id="M320" style="vertical-align:-3.50804pt" version="1.1" viewbox="0 0 110.125 20.2125" width="110.125" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg>.</table>

Journal of Applied Mathematics

fig1

Figure 1

Figure 1: A BDDC Preconditioner for the Rotated <svg     style="vertical-align:-4.32007pt;width:25.5px;" id="M1" height="20.450001" version="1.1" viewBox="0 0 25.5 20.450001" width="25.5"  xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg">
	
		
			<g transform="matrix(.022,-0,0,-.022,.062,15.012)"><path id="x1D444" d="M745 361q0 -134 -83.5 -233t-214.5 -130l16 -11q97 -67 250 -132l-8 -23q-76 3 -131 16q-81 19 -242 125l-20 13q-129 8 -209 91t-80 208q0 160 116 271t289 111q136 0 226.5 -83t90.5 -223zM645 356q0 127 -57.5 201.5t-169.5 74.5q-126 0 -210.5 -104.5t-84.5 -248.5
q0 -97 46 -166.5t129 -87.5l84 15l29 -19q104 21 169 121.5t65 213.5z" /></g>

			<g transform="matrix(.016,-0,0,-.016,17.275,20.388)"><path id="x31" d="M384 0h-275v27q67 5 81.5 18.5t14.5 68.5v385q0 38 -7.5 47.5t-40.5 10.5l-48 2v24q85 15 178 52v-521q0 -55 14.5 -68.5t82.5 -18.5v-27z" /></g>

		
	
</svg> FEM for Elliptic Problems with Discontinuous Coefficients 

Journal of Applied Mathematics

A BDDC Preconditioner for the Rotated FEM for Elliptic Problems with Discontinuous Coefficients

Figure 1