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The Global ETD Search service is a free service for researchers
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Networked Digital Library of Theses and Dissertations.
Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
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Showing 11 to 14 of 14 (0.028 seconds)Spelling suggestions: "subject:"imultaneously"" "subject:"cimultaneously""
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Power Integrity and Electromagnetic Compatibility Design for High-speed Computer PackageChen, Sin-Ting 03 July 2006 (has links)
This thesis focuses on the modeling and solutions of the simultaneous switching noise (SSN) problems in the power delivery networks (PDN) of high-speed digital circuit packages. An efficient numerical approach based on two-dimension (2D) finite-difference time-domain (FDTD) method combined with the lumped circuit model of the interconnection is proposed to model the PDN of a package and PCB. Based on this approach, the mechanism of noise coupling between package and PCB can be analyzed. In addition, a novel photonic crystal power layer (PCPL) design for the PDN of the package or PCB is proposed to suppress the SSN. The periodic High-Dk material is embedded into the substrate layer between the power and ground planes. Both modeling and measurement demonstrate the PCPL can form a wide stopband well with excellent suppression of the SSN propagation in the substrate and the corresponding electromagnetic interference (EMI).
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Microbeam Irradiation as a Simultaneously Integrated Boost in a Conventional Whole-Brain Radiotherapy ProtocolJaekel, Felix, Bräuer-Krisch, Elke, Bartzsch, Stefan, Laissue, Jean, Blattmann, Hans, Scholz, Marten, Soloviova, Julia, Hildebrandt, Guido, Schültke, Elisabeth 02 February 2024 (has links)
Microbeam radiotherapy (MRT), an experimental high-dose rate concept with spatial
fractionation at the micrometre range, has shown a high therapeutic potential as well as good
preservation of normal tissue function in pre-clinical studies. We investigated the suitability of MRT
as a simultaneously integrated boost (SIB) in conventional whole-brain irradiation (WBRT). A 174 Gy
MRT SIB was administered with an array of quasi-parallel, 50 m wide microbeams spaced at a
centre-to-centre distance of 400 m either on the first or last day of a 5 4 Gy radiotherapy schedule
in healthy adult C57 BL/6J mice and in F98 glioma cell cultures. The animals were observed for signs
of intracranial pressure and focal neurologic signs. Colony counts were conducted in F98 glioma cell
cultures. No signs of acute adverse effects were observed in any of the irradiated animals within
3 days after the last irradiation fraction. The tumoricidal effect on F98 cell in vitro was higher when
the MRT boost was delivered on the first day of the irradiation course, as opposed to the last day.
Therefore, the MRT SIB should be integrated into a clinical radiotherapy schedule as early as possible.
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The influence of uncertainty and liquidity constraints on liquid asset holdings of credit card revolversBi, Lan 07 October 2005 (has links)
No description available.
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Simultane Erfassung cerebraler Aktivität mittels Dipol-Quellenlokalisation und funktioneller MRT am Beispiel einer somatosensorischen KategorisierungsaufgabeThees, Sebastian 10 November 2004 (has links)
Mit dieser Arbeit ist es erstmalig gelungen, funktionelle MRT und Dipol-Quellenlokalisation in einer Weise zu kombinieren, die es erlaubt, ein und dieselbe kortikale Aktivität simultan mit beiden Verfahren zu erfassen. Insbesondere wurde dies durch (a) Korrektur eines vom Tomographen induzierten Artefaks in den EKPs und (b) durch eine deutliche Verbesserung des experimentellen Designs, und damit einer wesentlich effektiveren Nutzung von EEG und fMRT-Messzeit erreicht. So wurde es dadurch möglich, mit beiden Methoden die kortikale Aktivität einer Einzelpulsstimulation noch aufzulösen. Eine wesentliche Voraussetzung für die simultane Kombination beider Verfahren: Aufgrund der sehr verschiedenen Latenzen von elektrophysiologischer (< 1ms) und vaskulärer (SII->ant. Inseln und medialeWand) in Übereinstimmung mit der Literatur (Forss et al., 1996; Mauguiere et al., 1997b) blieb. So ergab die Quellenlokalisation für die Wahlreaktionsaufgabe fünf Dipole innerhalb des Gehirns, welche mittels Koregistrierung den Aktivierungen des primären somatosensorschen Kortex (20 - 140ms), des sekundären somatosensorischen Kortex (50 - 150ms), der beiden anterioren Inseln (80 - 140ms) und des supplementär-motorischen Region (90 - 140ms, 220 - 270ms) aus der funktionellen MRT zugeordnet wurden. Durch einen Vergleich der Aktivierungsmuster von Wahl- und Einfachreaktionsaufgabe jeweils in der Dipol-Quellenanalyse und in der funktionellen MRT konnten weitere Belege dafür gefunden werden, daß, wie in der Literatur postuliert (Romo and Salinas, 2001), der kontralaterale sekundäre somatosensorische Kortex an der Kategorisierung somatosensorischer Stimulusattribute beteiligt ist. So ergab ein Vergleich der Dipolzeitverläufe für Wahl- und Einfachreaktionsaufgabe lediglich für den Dipol im kontralateral somatosensorischen Kortex im Intervall 57-62 ms nach Stimulusapplikation einen signifikant unterschiedlichen Aktivierungsverlauf (p < 0,001). Übereinstimmend zeigte die funktionelle MRT für die Wahlreaktionsaufgabe neben einer stärkeren Aktivierung der SMA eine hochsignifikant stärkere Aktivierung im Areal des kontralateralen sekundären somatosensorischen Kortex (p-cluster < 0,001). / In this study, we have shown that it is feasible to perform dipole source analysis and fMRI based on the same neuronal activity associated with somatosensory categorization. This was possible by reduction of scanner-induced baseline artifact interfering with the ERPs as well as an optimized experimental protocol for interleaved EEG and fMRI acquisition. We consider this study to be a further step toward imaging brain activity simultaneously at high spatial and temporal resolution. Since an event-related protocol with a single brief pulse stimulation paradigm was successfully employed, this approach seems to be suitable for the investigation of cognitive tasks. By further technical improvements also the exploration of brain activity in single subjects might become possible, opening the field of clinical applications. In particular for the characterization of irregular and nonreproducible events, a substantial contribution of combined EEG–fMRI studies toward a more detailed understanding of physiological processes underlying cerebral activations is expected.
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