Sökning: "nuclear engineering"

Visar resultat 1 - 5 av 311 avhandlingar innehållade orden nuclear engineering.

  1. 1. Spectral Mammography with X-Ray Optics and a Photon-Counting Detector

    Författare :Erik Fredenberg; Mats Danielsson; Björn Cederström; Jeffrey H. Siewerdsen; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; mammography; x-ray optics; photon counting; spectral shaping; spectral imaging; collimation; radiation dose; signal-to-noise ratio; quantum noise; anatomical noise; spatial resolution; x-ray flux; ; TECHNOLOGY; TEKNIKVETENSKAP; Engineering physics; Teknisk fysik; Optical physics; Optisk fysik; Other engineering physics; Övrig teknisk fysik; Electrical engineering; electronics and photonics; Elektroteknik; elektronik och fotonik; Medical engineering; Medicinsk teknik; Radiological research; Radiologisk forskning;

    Sammanfattning : Early detection is vital to successfully treating breast cancer, and mammography screening is the most efficient and wide-spread method to reach this goal. Imaging low-contrast targets, while minimizing the radiation exposure to a large population is, however, a major challenge. LÄS MER

  2. 2. Increasing the hosting capacity of distributed energy resources using storage and communication

    Författare :Nicholas Etherden; Sami Repo; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Renewable Energy Generation; Energy Storage; Hosting Capacity; Curtailment; Demand Response; Dynamic Line Rating; Power System Communication; Smart Grid; Förnyelsebara energikällor; Energilagring; Acceptansgräns; Kommunikation i kraftsystem; Smarta elnät; Energy Engineering; Energiteknik; Electric Power Engineering; Elkraftteknik;

    Sammanfattning : The use of electricity from Distributed Energy Resources like wind and solar powerwill impact the performance of the electricity network and this sets a limit to theamount of such renewables that can be connected. Investment in energy storage andcommunication technologies enables more renewables by operating the networkcloser to its limits. LÄS MER

  3. 3. On integrity assessment of IGBT-based power stacks used in magnet power supplies for particle accelerators

    Författare :Panagiotis Asimakopoulos; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : This thesis analyses an electrical testing method for assessing the integrity of an IGBT-based power stack assembly during factory acceptance tests and service stops. The method combines vce measurements with high current in the Zero Temperature Coefficient (ZTC) operating region and with low sensing current within a specific current cycle using a proposed sampling and filtering technique. LÄS MER

  4. 4. Exploring the future low-carbon electricity system: impacts of nuclear power and demand patterns

    Författare :Xiaoming Kan; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; net system cost; electricity supply mix; Low-carbon electricity system; variable renewable energy; nuclear power; electricity system cost; demand pattern; energy system modeling;

    Sammanfattning : To achieve the climate goals set by the Paris Agreement, the global electricity system is expected to transition towards a low-carbon electricity system. The future low-carbon electricity system is uncertain regarding both generation and demand. LÄS MER

  5. 5. A Segmented Silicon Strip Detector for Photon-Counting Spectral Computed Tomography

    Författare :Cheng Xu; Hans Bornefalk; Mats Danielsson; Ami Altman; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; photon counting; spectral computed tomography; silicon strip detector; ASIC; energy resolution; cadmium telluride; charge sharing; Monte Carlo simulation; synchrotron;

    Sammanfattning : Spectral computed tomography with energy-resolving detectors has a potential to improve the detectability of images and correspondingly reduce the radiation dose to patients by extracting and properly using the energy information in the broad x-ray spectrum. A silicon photon-counting detector has been developed for spectral CT and it has successfully solved the problem of high photon flux in clinical CT applications by adopting the segmented detector structure and operating the detector in edge-on geometry. LÄS MER