Sökning: "Radiation sciences"

Visar resultat 31 - 35 av 1318 avhandlingar innehållade orden Radiation sciences.

1. 31. Secondary absorbed dose distributions and radiation quality in light ion therapy

   Författare :Martha Hultqvist; Irena Gudowska; Tatsuhiko Sato; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; secondary doses; light ion therapy; radiation quality; Monte Carlo simulation; Medical Radiation Physics; medicinsk strålningsfysik;

   Sammanfattning : Radiotherapy with light ions offers the possibility of achieving a dose distribution which is highly conformed to the target volume while sparing normal tissues. For ions heavier than protons, an additional advantage is the increased Relative Biological Effectiveness (RBE) as compared to conventional photon and electron beams. LÄS MER

3. 32. Demonstrating reliableinstrumentation in theATLAS Tile Calorimeter : Fault tolerance and redundancy in hardware and firmwarefor the Phase-II Demonstrator project in preparation forHigh Luminosity LHC at CERN

   Författare :Henrik Åkerstedt; Samuel B. Silverstein; Jón E. Gudmundsson; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; CERN; ATLAS; Tile calorimeter; TileCal; FPGA; SEU; TMR; Kintex; Demonstrator; DaughterBoard; Radiation testing; Radiation tolerant; Physics; fysik;

   Sammanfattning : The Large Hadron Collider at CERN is scheduled to undergo upgrades in 2026-2028 to significantly increase its luminosity. These upgrades, while providing the experiments with a higher collision rate, pose a number of challenges to the design of the hardware and software in the detectors. LÄS MER

4. 33. Historical anthropogenic radiative forcing of changes in biogenic secondary organic aerosol

   Författare :Juan Camilo Acosta Navarro; Ilona Riipinen; Annica Ekman; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : Human activities have lead to changes in the energy balance of the Earth and the global climate. Changes in atmospheric aerosols are the second largest contributor to climate change after greenhouse gases since 1750 A.D. LÄS MER

5. 34. Climatology and firn processes in the lower accumulation area of the Greenland ice sheet

   Författare :Charalampos Charalampidis; Veijo Pohjola; Dirk van As; Rickard Pettersson; Douglas Benn; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; climate change; Greenland ice sheet; accumulation area; automatic weather stations; surface energy balance; melt–albedo feedback; surface mass budget; snow; firn; meltwater; percolation; refreezing; runoff;

   Sammanfattning : The Greenland ice sheet is the largest Northern Hemisphere store of fresh water, and it is responding rapidly to the warming climate. In situ observations document the changing ice sheet properties in the lower accumulation area, Southwest Greenland. LÄS MER

7. 35. Surface energy exchange and land-atmosphere interactions of Arctic and subarctic tundra ecosystems under climate change

   Författare :Christian Stiegler; Institutionen för naturgeografi och ekosystemvetenskap; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Surface energy exchange; Arctic and subarctic tundra; climate change; permafrost; eddy covariance; snow cover; micrometeorology;

   Sammanfattning : The surface energy balance determines the functioning of any ecosystem on the Earth but is still poorly understood in Arctic and subarctic biomes. In a dynamic system, such as the Earth’s climate, any change in its characteristics modifies the exchange of energy, water, and greenhouse gases between the surface and the atmosphere. LÄS MER