{"id":{"repo_id":"rice","oai_identifier":"oai:repository.rice.edu:1911/103605"},"canonical_url":"https://search.dev.ndltd.org/etd/rice/oai:repository.rice.edu:1911/103605","repository":{"repo_id":"rice","name":"Rice University","base_url":"https://repository.rice.edu/server/oai/request"},"display":{"title":"The nonlinear differential semblance algorithm for plane waves in layered media","abstract":"This thesis proposes an alternative approach to the output least-squares (OLS) seismic inversion for layered-media. The latter cannot guarantee a reliable solution for either synthetic or field data, because of the existence of many spurious local minima of the objective function for typical data, which lack low-frequency energy. To recover the low-frequency lacuna of typical data, I formulate waveform inversion into a differential semblance optimization (DSO) problem with artificial low-frequency data as control variables. To my knowledge, this approach is the first version of differential semblance with non-linear modeling that may properly account for nonlinear effects of wave propagation, such as multiple reflections. Numerical experiments with synthetic data indicate the smoothness and convexity of the proposed objective function. These results suggest that gradient-related algorithms may successfully approximate a global minimizer from a crude initial guess for typical band-limited data.","abstract_html":"This thesis proposes an alternative approach to the output least-squares (OLS) seismic inversion for layered-media. The latter cannot guarantee a reliable solution for either synthetic or field data, because of the existence of many spurious local minima of the objective function for typical data, which lack low-frequency energy. To recover the low-frequency lacuna of typical data, I formulate waveform inversion into a differential semblance optimization (DSO) problem with artificial low-frequency data as control variables. To my knowledge, this approach is the first version of differential semblance with non-linear modeling that may properly account for nonlinear effects of wave propagation, such as multiple reflections. Numerical experiments with synthetic data indicate the smoothness and convexity of the proposed objective function. These results suggest that gradient-related algorithms may successfully approximate a global minimizer from a crude initial guess for typical band-limited data.","abstract_has_math":false,"creators":["Sun, Dong"],"institution":"Rice University","degree_name":"Master of Arts","degree_level":"Masters","degree_discipline":"Engineering","degree_department":null,"school":null,"contributors":[],"advisors":["Symes, William W."],"committee_chairs":[],"committee_members":[],"year":2008,"date_issued":"2008","date_published":"2008","updated_at":"2026-07-24T04:10:24Z","subjects":["Geophysics","Mathematics","Pure sciences","Earth sciences"],"languages":["eng"],"rights":["Copyright is held by the author, unless otherwise indicated. Permission to reuse, publish, or reproduce the work beyond the bounds of fair use or other exemptions to copyright law must be obtained from the copyright holder."],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://hdl.handle.net/1911/103605","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Symes, William W."]},{"key":"dc:creator","label":"Author","values":["Sun, Dong"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2018-12-03T18:31:48Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2018-12-03T18:31:48Z"]},{"key":"dc:date.issued","label":"Date","values":["2008"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Engineering"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Masters"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Arts"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["Rice University"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Geophysics","Mathematics","Pure sciences","Earth sciences"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright is held by the author, unless otherwise indicated. 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To my knowledge, this approach is the first version of differential semblance with non-linear modeling that may properly account for nonlinear effects of wave propagation, such as multiple reflections. Numerical experiments with synthetic data indicate the smoothness and convexity of the proposed objective function. These results suggest that gradient-related algorithms may successfully approximate a global minimizer from a crude initial guess for typical band-limited data."]},{"key":"dc:title","label":"Title","values":["The nonlinear differential semblance algorithm for plane waves in layered media"]}]}],"canonical_facts":{"dc:contributor.advisor":["Symes, William W."],"dc:creator":["Sun, Dong"],"dc:date.accessioned":["2018-12-03T18:31:48Z"],"dc:date.available":["2018-12-03T18:31:48Z"],"dc:date.issued":["2008"],"dc:description.abstract":["This thesis proposes an alternative approach to the output least-squares (OLS) seismic inversion for layered-media. The latter cannot guarantee a reliable solution for either synthetic or field data, because of the existence of many spurious local minima of the objective function for typical data, which lack low-frequency energy. To recover the low-frequency lacuna of typical data, I formulate waveform inversion into a differential semblance optimization (DSO) problem with artificial low-frequency data as control variables. To my knowledge, this approach is the first version of differential semblance with non-linear modeling that may properly account for nonlinear effects of wave propagation, such as multiple reflections. Numerical experiments with synthetic data indicate the smoothness and convexity of the proposed objective function. These results suggest that gradient-related algorithms may successfully approximate a global minimizer from a crude initial guess for typical band-limited data."],"dc:identifier.uri":["https://hdl.handle.net/1911/103605"],"dc:language.iso":["eng"],"dc:rights":["Copyright is held by the author, unless otherwise indicated. Permission to reuse, publish, or reproduce the work beyond the bounds of fair use or other exemptions to copyright law must be obtained from the copyright holder."],"dc:subject":["Geophysics","Mathematics","Pure sciences","Earth sciences"],"dc:title":["The nonlinear differential semblance algorithm for plane waves in layered media"],"dc:type":["Thesis"],"thesis:degree_discipline":["Engineering"],"thesis:degree_level":["Masters"],"thesis:degree_name":["Master of Arts"],"thesis:institution_name":["Rice University"]},"updated_at":"2026-07-24T04:10:24Z"}