{"_buckets": {"deposit": "ea6b083b-0a51-49c4-a1dd-d38963cc34ed"}, "_deposit": {"created_by": 1, "id": "45458", "owners": [1], "pid": {"revision_id": 0, "type": "depid", "value": "45458"}, "status": "published"}, "_oai": {"id": "oai:repo.qst.go.jp:00045458", "sets": ["1"]}, "author_link": ["451654", "451650", "451655", "451651", "451656", "451653", "451657", "451652"], "item_8_biblio_info_7": {"attribute_name": "書誌情報", "attribute_value_mlt": [{"bibliographicIssueDates": {"bibliographicIssueDate": "2008-11", "bibliographicIssueDateType": "Issued"}, "bibliographicIssueNumber": "11", "bibliographicPageEnd": "4932", "bibliographicPageStart": "4924", "bibliographicVolumeNumber": "35", "bibliographic_titles": [{"bibliographic_title": "Medical Physics"}]}]}, "item_8_description_5": {"attribute_name": "抄録", "attribute_value_mlt": [{"subitem_description": "Information on electron density is important for radiotherapy treatment planning in order to optimize\nthe dose distribution in the target volume of a patient. At present, the electron density is\nderived from a computed tomography (CT) number measured in x-ray CT scanning; however, there\nare uncertainties due to the beam hardening effect and the method by which the electron density is\nconverted from the CT number. In order to measure the electron density with an accuracy of +-1%,\nthe authors have developed dual-energy x ray CT using monochromatic x rays. They experimentally\nproved that the measured linear attenuation coefficients were only a few percent lower than the\ntheoretical ones, which led to an accuracy within 2% for the electron density. There were three\nfactors causing inaccuracy in the linear attenuation coefficient and the electron density: the influence\nof scattered radiation, the nonlinearity in the detector response function, and a theoretical\nprocess to derive the electron density from the linear attenuation coefficients. The linear attenuation\ncoefficients of water were experimentally proved to differ by  1 - 2 % from the theoretical one even\nwhen the scattering effect was negligible. The nonlinearity of the response function played an\nimportant role in correcting the difference in the linear attenuation coefficient. Furthermore, the\ntheoretical process used for deriving the electron density from the linear attenuation coefficients\nintroduces about 0.6% deviation from the theoretical value into the resultant electron density. This\ndeviation occurs systematically so that it can be corrected. The authors measured the electron\ndensities for seven samples equivalent to soft tissue in dual-energy x-ray CT, and finally obtained\nthem with an accuracy of around +-1%.", "subitem_description_type": "Abstract"}]}, "item_8_source_id_9": {"attribute_name": "ISSN", "attribute_value_mlt": [{"subitem_source_identifier": "0094-2405", "subitem_source_identifier_type": "ISSN"}]}, "item_access_right": {"attribute_name": "アクセス権", "attribute_value_mlt": [{"subitem_access_right": "metadata only access", "subitem_access_right_uri": "http://purl.org/coar/access_right/c_14cb"}]}, "item_creator": {"attribute_name": "著者", "attribute_type": "creator", "attribute_value_mlt": [{"creatorNames": [{"creatorName": "Tsunoo, Takanori"}], "nameIdentifiers": [{"nameIdentifier": "451650", "nameIdentifierScheme": "WEKO"}]}, {"creatorNames": [{"creatorName": "Torikoshi, Masami"}], "nameIdentifiers": [{"nameIdentifier": "451651", "nameIdentifierScheme": "WEKO"}]}, {"creatorNames": [{"creatorName": "Ohno, Yumiko"}], "nameIdentifiers": [{"nameIdentifier": "451652", "nameIdentifierScheme": "WEKO"}]}, {"creatorNames": [{"creatorName": "Uesugi, Kentaro"}], "nameIdentifiers": [{"nameIdentifier": "451653", "nameIdentifierScheme": "WEKO"}]}, {"creatorNames": [{"creatorName": "Yagi, Naoto"}], "nameIdentifiers": [{"nameIdentifier": "451654", "nameIdentifierScheme": "WEKO"}]}, {"creatorNames": [{"creatorName": "角尾 卓紀", "creatorNameLang": "en"}], "nameIdentifiers": [{"nameIdentifier": "451655", "nameIdentifierScheme": "WEKO"}]}, {"creatorNames": [{"creatorName": "取越 正己", "creatorNameLang": "en"}], "nameIdentifiers": [{"nameIdentifier": "451656", "nameIdentifierScheme": "WEKO"}]}, {"creatorNames": [{"creatorName": "大野 由美子", "creatorNameLang": "en"}], "nameIdentifiers": [{"nameIdentifier": "451657", "nameIdentifierScheme": "WEKO"}]}]}, "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": "Measurement of electron density in dual-energy x-ray CT with monochromatic x rays and evaluation of its accuracy", "item_titles": {"attribute_name": "タイトル", "attribute_value_mlt": [{"subitem_title": "Measurement of electron density in dual-energy x-ray CT with monochromatic x rays and evaluation of its accuracy"}]}, "item_type_id": "8", "owner": "1", "path": ["1"], "permalink_uri": "https://repo.qst.go.jp/records/45458", "pubdate": {"attribute_name": "公開日", "attribute_value": "2009-03-26"}, "publish_date": "2009-03-26", "publish_status": "0", "recid": "45458", "relation": {}, "relation_version_is_last": true, "title": ["Measurement of electron density in dual-energy x-ray CT with monochromatic x rays and evaluation of its accuracy"], "weko_shared_id": -1}