<div dir="ltr">Seminari di Matematica Applicata, Dipartimento di Matematica "F. Casorati" e Istituto del CNR IMATI "E. Magenes" di Pavia.<br><br>Martedì 8 Aprile 2025, alle ore 15 precise, presso l'aula Beltrami del Dipartimento di Matematica,<br><br><h4 style="padding:0px;margin:0px 0px 10px;clear:none;color:rgb(23,28,36);font-weight:300;font-stretch:normal;font-size:24px;line-height:1.2;font-family:Montserrat,-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,sans-serif;font-size-adjust:none;font-kerning:auto;font-variant-alternates:normal;font-variant-ligatures:normal;font-variant-numeric:normal;font-variant-east-asian:normal;font-feature-settings:normal;box-sizing:border-box">Mourad Sini (RICAM)</h4><div><br></div><h4 style="padding:0px;margin:0px 0px 10px;clear:none;color:rgb(23,28,36);font-weight:300;font-stretch:normal;line-height:1.2;font-family:Montserrat,-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,sans-serif;box-sizing:border-box"><span style="color:rgb(34,34,34);font-family:Arial,Helvetica,sans-serif">terrà un seminario dal titolo:</span></h4><div><br></div><h3 style="padding:0px;margin:5px 0px 8px;clear:none;color:rgb(23,28,36);font-weight:300;font-stretch:normal;font-size:28px;line-height:1.2;font-family:Montserrat,-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,sans-serif;font-size-adjust:none;font-kerning:auto;font-variant-alternates:normal;font-variant-ligatures:normal;font-variant-numeric:normal;font-variant-east-asian:normal;font-feature-settings:normal;box-sizing:border-box">Analysis of inverse problems in ultrasound imaging using resonant perturbations.</h3><div><br></div><div><span style="color:rgb(61,61,61);font-family:Roboto,sans-serif;font-size:15px">Abstract: </span><span style="color:rgb(61,61,61);font-family:Roboto,sans-serif;font-size:15px">We will present recent results derived in the framework of inverse problems appearing in ultrasound imaging modalities using bubbles as resonant contrast agents. Such bubbles are small scaled but enjoy high contrasts of their mass density and bulk modulus. At the mathematical analysis level, the main advantage is that such contrast agents resonate at certain frequencies. Such resonant frequencies can be characterized as poles of the resolvents of the related Hamiltonians. The general features of our findings are as follows:</span></div><span style="color:rgb(61,61,61);font-family:Roboto,sans-serif;font-size:15px">1. Using time-harmonic measurements, in a band of frequencies, we can recover the already mentioned resonances. These resonances have the explicit signature of the material properties of the object (as the speed of propagation) which allows to reconstruct them.</span><br style="padding:0px;margin:0px;box-sizing:border-box;color:rgb(61,61,61);font-family:Roboto,sans-serif;font-size:15px"><span style="color:rgb(61,61,61);font-family:Roboto,sans-serif;font-size:15px">2. Using time-domain measurements, in a large enough time, we can recover the internal values of the travel time function. Using the related Eikonal equation, for instance, we can reconstruct the related speed of propagation.</span><div><div><span style="color:rgb(61,61,61);font-family:Roboto,sans-serif;font-size:15px;font-variant-ligatures:normal;text-decoration-style:initial;text-decoration-color:initial"><br>-----------------------------------------</span></div><div><span style="color:rgb(61,61,61);font-family:Roboto,sans-serif;font-size:15px;font-variant-ligatures:normal;text-decoration-style:initial;text-decoration-color:initial"><a href="https://matematica.unipv.it/ricerca/cicli-di-seminari/seminari-di-matematica-applicata/" target="_blank">https://matematica.unipv.it/ricerca/cicli-di-seminari/seminari-di-matematica-applicata/</a><div class="gmail-yj6qo"></div><div class="gmail-adL"></div><div class="gmail-adL"></div><div class="gmail-adL"></div><div class="gmail-adL"></div><div class="gmail-adL"></div><div class="gmail-adL"></div></span></div></div><br class="gmail-Apple-interchange-newline"></div>