Sökning: "Helena Sandström"

Visar resultat 1 - 5 av 6 avhandlingar innehållade orden Helena Sandström.

  1. 1. Contouring variability in radiosurgery - dosimetric and radiobiological implications

    Detta är en avhandling från Stockholm : Department of Physics, Stockholm University

    Författare :Helena Sandström; Iuliana Toma-Dasu; Mike Partridge; [2015]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; medicinsk strålningsfysik; Medical Radiation Physics;

    Sammanfattning : The use of Stereotactic Radiation Therapy (SRT) employing one large fraction of radiation, as in stereotactic radiosurgery (SRS), or few fractions of high doses, has continuously increased due to the technical development and the progress in dose delivery complemented by the positive clinical experience. The success of stereotactic radiation therapy depends on many clinical, dosimetric and radiobiological factors. LÄS MER

  2. 2. Internet services and security

    Detta är en avhandling från Luleå : Luleå tekniska universitet

    Författare :Helena Sandström; [2005]
    Nyckelord :;

    Sammanfattning : This thesis presents my research on IP Traceback and on QoS admission control. It also includes a brief discussion about the security problems we are facing today and how adding new network services affects the original Internet design. Internet security is an ever rising problem. LÄS MER

  3. 3. Contouring & planning variability in stereotactic radiosurgery How to assess and address the weakest link in stereotactic radiosurgery?

    Detta är en avhandling från Stockholm : Department of Physics, Stockholm University

    Författare :Helena Sandström; Iuliana Toma-Dasu; David Schlesinger; [2019]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; stereotactic radiosurgery; contouring variability; robust treatment planning; medicinsk strålningsfysik; Medical Radiation Physics;

    Sammanfattning : The use of stereotactic radiosurgery (SRS) employing one or a few fractions of high doses of radiation has continuously increased due to the technical development in dose delivery and morphological and functional imaging. As the target volume in SRS is usually defined without margins, the treatment success critically depends on accurate definition and contouring of the target volume and organs at risk (OARs) which are commonly situated in the proximity of the target making their precise delineation particularly important in order to limit possible normal tissue complications. LÄS MER

  4. 4. Centralized Disaster Management Collaboration in Turkey

    Detta är en avhandling från Uppsala : Acta Universitatis Upsaliensis

    Författare :Helena Hermansson; Daniel Nohrstedt; Charles Parker; Annica Sandström; [2017]
    Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; collaboration; disaster management; collaborative disaster management; cross-sector collaboration; trust; power balance; legitimacy; integration; local knowledge; local actors; civil society; interdependence; pre-existing relations; political affiliation; natural disaster; disaster response; damage assessment; aid distribution; search and rescue; decentralization; central-local collaboration; political-administrative system; Turkey; Van; Erciş; Statsvetenskap med inriktning mot krishantering och internationell samverkan; Statsvetenskap med inriktning mot krishantering och internationell samverkan;

    Sammanfattning : Following unprecedented earthquakes in 1999, highly centralized Turkey initiated reforms that aimed to improve disaster management collaboration and to empower local authorities. In 2011, two earthquakes hit the country anew affecting the city of Van and town of Erciş in Turkey’s southeast. LÄS MER

  5. 5. Centralized Disaster Management Collaboration in Turkey

    Detta är en avhandling från Uppsala : Acta Universitatis Upsaliensis

    Författare :Helena Hermansson; Daniel Nohrstedt; Charles Parker; Annica Sandström; [2017]
    Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; collaboration; disaster management; collaborative disaster management; cross-sector collaboration; trust; power balance; legitimacy; integration; local knowledge; local actors; civil society; interdependence; pre-existing relations; political affiliation; natural disaster; disaster response; damage assessment; aid distribution; search and rescue; decentralization; central-local collaboration; political-administrative system; Turkey; Van; Erciş; Statskunskap; Political Science;

    Sammanfattning : Following unprecedented earthquakes in 1999, highly centralized Turkey initiated reforms that aimed to improve disaster management collaboration and to empower local authorities. In 2011, two earthquakes hit the country anew affecting the city of Van and town of Erciş in Turkey’s southeast. LÄS MER