Optimal Order Error Estimates of a Modified Nonconforming Rotated <svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-4.1996pt" id="M1" height="15.599pt" version="1.1" viewBox="-0.0657574 -11.3994 19.0107 15.599" width="19.0107pt"><g transform="matrix(.017,0,0,-0.017,0,0)"><path id="g113-82" d="M699 368C699 549 574 666 407 666C186 666 23 488 23 277C23 113 129 -3 288 -13L307 -26C431 -111 501 -139 533 -147C559 -154 613 -163 658 -164L666 -141C597 -111 507 -66 430 -11L416 -1C580 42 699 190 699 368ZM601 371C601 227 518 54 381 22L354 40L278 24C175 47 120 145 120 269C120 451 235 631 398 631C540 631 601 521 601 371Z"/></g><g transform="matrix(.012,0,0,-0.012,12.304,4.134)"><path id="g50-50" d="M389 0V32C297 38 291 46 291 118V635C234 613 175 595 109 583V556L161 554C203 552 207 547 207 497V118C207 46 201 38 110 32V0H389Z"/></g></svg> IFEM for Interface Problems

<div>Convergence rates in <span class="nowrap"><svg height="11.6412pt" id="M231" style="vertical-align:-0.04979992pt" version="1.1" viewbox="-0.0498162 -11.5914 12.262 11.6412" width="12.262pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M541 160L512 170C485 116 462 88 439 67C411 41 376 35 318 35C272 35 238 37 224 48C207 61 205 85 212 121L290 533C305 611 308 615 391 622L397 650H139L133 622C217 615 221 612 206 533L126 118C111 41 103 34 23 26L17 0H474C489 31 528 124 541 160Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,7.185,-5.741)"><path d="M414 144C384 79 371 75 317 75H135L276 221C367 316 408 376 408 465C408 570 327 635 237 635C179 635 131 609 100 575L42 494L67 471C94 510 138 565 205 565C277 565 321 517 321 435C321 348 258 270 195 195C146 137 88 81 33 26V0H411C423 44 433 88 446 135L414 144Z"></path></g></svg>-</span>norm (a) and broken energy norm (b) for Example <a href="https://static.hindawi.com/articles/mpe/volume-2020/2081948/figures/#ex1">1</a>.</div>

Mathematical Problems in Engineering

fig2

Figure 2

Figure 2: Optimal Order Error Estimates of a Modified Nonconforming Rotated <svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-4.1996pt" id="M1" height="15.599pt" version="1.1" viewBox="-0.0657574 -11.3994 19.0107 15.599" width="19.0107pt"><g transform="matrix(.017,0,0,-0.017,0,0)"><path id="g113-82" d="M699 368C699 549 574 666 407 666C186 666 23 488 23 277C23 113 129 -3 288 -13L307 -26C431 -111 501 -139 533 -147C559 -154 613 -163 658 -164L666 -141C597 -111 507 -66 430 -11L416 -1C580 42 699 190 699 368ZM601 371C601 227 518 54 381 22L354 40L278 24C175 47 120 145 120 269C120 451 235 631 398 631C540 631 601 521 601 371Z"/></g><g transform="matrix(.012,0,0,-0.012,12.304,4.134)"><path id="g50-50" d="M389 0V32C297 38 291 46 291 118V635C234 613 175 595 109 583V556L161 554C203 552 207 547 207 497V118C207 46 201 38 110 32V0H389Z"/></g></svg> IFEM for Interface Problems 

Mathematical Problems in Engineering

Optimal Order Error Estimates of a Modified Nonconforming Rotated IFEM for Interface Problems

Figure 2