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l350 -516h5l48 257q25 131 25 171q0 34 -17.5 45t-77.5 15l7 28h240z" /></g><g transform="matrix(.022,-0,0,-.022,220.75,15.825)"><use xlink:href="#x2F" /></g><g transform="matrix(.022,-0,0,-.022,229.986,15.825)"><path id="x30" d="M241 635q53 0 94 -28.5t63.5 -76t33.5 -102.5t11 -116q0 -58 -11 -112.5t-34 -103.5t-63.5 -78.5t-94.5 -29.5t-95 28t-64.5 75t-34.5 102.5t-11 118.5q0 58 11.5 112.5t34.5 103t64.5 78t95.5 29.5zM238 602q-32 0 -55.5 -25t-35.5 -68t-17.5 -91t-5.5 -105
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<table>The loss probability and the mean number of busy servers at Station 2 as functions of the system load for the <svg height="11.425" id="M474" style="vertical-align:-0.0pt" version="1.1" viewbox="0 0 46.587502 11.425" width="46.587502" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg>s with different correlation.</table>

Mathematical Problems in Engineering

fig5

Figure 5

Figure 5: A Tandem <svg style="vertical-align:-2.934pt;width:240.825px;" id="M1" height="19.5375" version="1.1" viewBox="0 0 240.825 19.5375" width="240.825" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg"><g transform="matrix(.022,-0,0,-.022,.062,15.825)"><path id="x42" d="M372 352v-2q176 -27 176 -159q0 -99 -95 -151q-73 -40 -196 -40h-221v28q65 5 78.5 19t13.5 76v404q0 63 -12 77t-72 18v28h257q102 0 150 -34q26 -18 41 -48.5t15 -65.5q0 -111 -135 -150zM213 362h47q80 0 117.5 32t37.5 96q0 56 -33 92t-100 36q-41 0 -56 -10
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l350 -516h5l48 257q25 131 25 171q0 34 -17.5 45t-77.5 15l7 28h240z" /></g><g transform="matrix(.022,-0,0,-.022,220.75,15.825)"><use xlink:href="#x2F" /></g><g transform="matrix(.022,-0,0,-.022,229.986,15.825)"><path id="x30" d="M241 635q53 0 94 -28.5t63.5 -76t33.5 -102.5t11 -116q0 -58 -11 -112.5t-34 -103.5t-63.5 -78.5t-94.5 -29.5t-95 28t-64.5 75t-34.5 102.5t-11 118.5q0 58 11.5 112.5t34.5 103t64.5 78t95.5 29.5zM238 602q-32 0 -55.5 -25t-35.5 -68t-17.5 -91t-5.5 -105
q0 -76 10 -138.5t37 -107.5t69 -45q32 0 55.5 25t35.5 68.5t17.5 91.5t5.5 105t-5.5 105.5t-18 92t-36 68t-56.5 24.5z" /></g></svg> Queue with Group Occupation of Servers at the Second Station 

Mathematical Problems in Engineering

A Tandem Queue with Group Occupation of Servers at the Second Station

Figure 5