{"created":"2023-05-15T16:32:46.065554+00:00","id":4737,"links":{},"metadata":{"_buckets":{"deposit":"27f1d64d-7564-4ba5-8930-db03f19c26fd"},"_deposit":{"created_by":2,"id":"4737","owners":[2],"pid":{"revision_id":0,"type":"depid","value":"4737"},"status":"published"},"_oai":{"id":"oai:nagasaki-u.repo.nii.ac.jp:00004737","sets":["52:56"]},"author_link":["19290","19291"],"item_2_biblio_info_6":{"attribute_name":"書誌情報","attribute_value_mlt":[{"bibliographicIssueDates":{"bibliographicIssueDate":"2014-05-05","bibliographicIssueDateType":"Issued"},"bibliographicIssueNumber":"1","bibliographicPageEnd":"278","bibliographicPageStart":"271","bibliographicVolumeNumber":"2","bibliographic_titles":[{"bibliographic_title":"Earth Surface Dynamics"}]}]},"item_2_description_4":{"attribute_name":"抄録","attribute_value_mlt":[{"subitem_description":"Knickpoints often form in bedrock rivers in response to base-level lowering. These knickpoints can migrate upstream without dissipating. In the case of alluvial rivers, an impulsive lowering of base level due to, for example, a fault associated with an earthquake or dam removal commonly produces smooth, upstream-progressing degradation; the knickpoint associated with suddenly lowered base level quickly dissipates. Here, however, we use experiments to demonstrate that under conditions of Froude-supercritical flow over an alluvial bed, an instantaneous drop in base level can lead to the formation of upstream-migrating knickpoints that do not dissipate. The base-level fall can generate a single knickpoint, or multiple knickpoints. Multiple knickpoints take the form of cyclic steps, that is, trains of upstream-migrating bedforms, each bounded by a hydraulic jump upstream and downstream. In our experiments, trains of knickpoints were transient, eventually migrating out of the alluvial reach as the bed evolved to a new equilibrium state regulated with lowered base level. Thus the allogenic perturbation of base-level fall can trigger the autogenic generation of multiple knickpoints which are sustained until the alluvial reach recovers a graded state.","subitem_description_type":"Abstract"}]},"item_2_description_63":{"attribute_name":"引用","attribute_value_mlt":[{"subitem_description":"Earth Surface Dynamics, 2(1), pp.271-278; 2014","subitem_description_type":"Other"}]},"item_2_publisher_33":{"attribute_name":"出版者","attribute_value_mlt":[{"subitem_publisher":"Copernicus GmbH"}]},"item_2_relation_12":{"attribute_name":"DOI","attribute_value_mlt":[{"subitem_relation_type":"isIdenticalTo","subitem_relation_type_id":{"subitem_relation_type_id_text":"10.5194/esurf-2-271-2014","subitem_relation_type_select":"DOI"}}]},"item_2_rights_13":{"attribute_name":"権利","attribute_value_mlt":[{"subitem_rights":"c Author(s) 2014. This work is distributed under the Creative Commons Attribution 3.0 License."}]},"item_2_source_id_8":{"attribute_name":"EISSN","attribute_value_mlt":[{"subitem_source_identifier":"2196632X","subitem_source_identifier_type":"ISSN"}]},"item_2_version_type_16":{"attribute_name":"著者版フラグ","attribute_value_mlt":[{"subitem_version_resource":"http://purl.org/coar/version/c_970fb48d4fbd8a85","subitem_version_type":"VoR"}]},"item_creator":{"attribute_name":"著者","attribute_type":"creator","attribute_value_mlt":[{"creatorNames":[{"creatorName":"Cantelli, Alessandro"}],"nameIdentifiers":[{}]},{"creatorNames":[{"creatorName":"Muto, Tetsuji"}],"nameIdentifiers":[{}]}]},"item_files":{"attribute_name":"ファイル情報","attribute_type":"file","attribute_value_mlt":[{"accessrole":"open_date","date":[{"dateType":"Available","dateValue":"2020-12-21"}],"displaytype":"detail","filename":"ESD2_271.pdf","filesize":[{"value":"1.1 MB"}],"format":"application/pdf","licensetype":"license_note","mimetype":"application/pdf","url":{"label":"ESD2_271.pdf","url":"https://nagasaki-u.repo.nii.ac.jp/record/4737/files/ESD2_271.pdf"},"version_id":"b1952a29-443b-4b1a-9a6b-4a316cb32478"}]},"item_language":{"attribute_name":"言語","attribute_value_mlt":[{"subitem_language":"eng"}]},"item_resource_type":{"attribute_name":"資源タイプ","attribute_value_mlt":[{"resourcetype":"journal article","resourceuri":"http://purl.org/coar/resource_type/c_6501"}]},"item_title":"Multiple knickpoints in an alluvial river generated by a single instantaneous drop in base level: experimental investigation","item_titles":{"attribute_name":"タイトル","attribute_value_mlt":[{"subitem_title":"Multiple knickpoints in an alluvial river generated by a single instantaneous drop in base level: experimental investigation"}]},"item_type_id":"2","owner":"2","path":["56"],"pubdate":{"attribute_name":"公開日","attribute_value":"2015-10-02"},"publish_date":"2015-10-02","publish_status":"0","recid":"4737","relation_version_is_last":true,"title":["Multiple knickpoints in an alluvial river generated by a single instantaneous drop in base level: experimental investigation"],"weko_creator_id":"2","weko_shared_id":-1},"updated":"2023-05-16T03:16:17.736916+00:00"}