Performance Portability Study of Linear Algebra Kernels in OpenCL

The performance portability of OpenCL kernel implementations for common memory bandwidth limited linear algebra operations across different hardware generations of the same vendor as well as across vendors is studied. Certain combinations of kernel implementations and work sizes are found to exhibit good performance across compute kernels, hardware generations, and, to a lesser degree, vendors. As a consequence, it is demonstrated that the optimization of a single kernel is often sufficient to obtain good performance for a large class of more complicated operations.Comment: 11 pages, 8 figures, 2 tables, International Workshop on OpenCL 201

Scintillation decay-time constants for alpha particles and electrons in liquid xenon

Understanding liquid xenon scintillation and ionization processes is of great interest to improve analysis methods in current and future detectors. In this paper, we investigate the dynamics of the scintillation process for excitation by $\mathcal{O}$(10 keV) electrons from a $^{83m}$Kr source and $\mathcal{O}$(6 MeV) $\alpha$-particles from a $^{222}$Rn source, both mixed with the xenon target. The single photon sampling method is used to record photon arrival times in order to obtain the corresponding time distributions for different applied electric fields between about 0.8 V/cm to 1.2 kV/cm. Energy and field dependences of the signals which are observed in the results are discussed.Comment: 11 pages, 9 figures; replaced with published manuscript versio

Transmission of xenon scintillation light through PTFE

Polytetrafluoroethylene (PTFE), also known as Teflon, is a common material used in the construction of liquid xenon detectors due to its high reflectivity for the VUV scintillation light of xenon. We present transmission measurements of PTFE for xenon scintillation light with peak emission at a wavelength of 175 nm. PTFE discs of different thicknesses are installed in front of a photosensor in two setups. One is filled with gaseous xenon, the other with liquid xenon. The measurements performed with the gaseous xenon setup at room temperature yield a transmission coefficient of $\lambda = \bigl(350{{}^{+60}_{~-0}}{}\,{\mathrm{(sys)}}\,\pm\, 50\,{\mathrm{(stat)}}\bigr)\,\mathrm{\mu m}$. This is found to be in agreement with the observations made using the liquid xenon setup.Comment: 12 pages, 5 figures, 2 tables; accepted for publication in JINS

Characterization of alpha and beta interactions in liquid xenon

Liquid xenon based detectors have achieved great sensitivities in rare event searches. Precise knowledge of the scintillation and ionization responses of the medium is essential to correctly model different interaction types in the detector including both signal and background-like ones. The response of liquid xenon to low energy electrons and to alpha particles has been studied in the Heidelberg Xenon (HeXe) dual-phase xenon TPC. We determine the light and charge signal yields for keV-energy electrons and MeV-energy alpha particles as well as the electron drift velocity for electric drift fields between 7.5 and 1640 V/cm. A three dimensional simulation using COMSOL Multiphysics(R) is used to characterize the applied drift field and its homogeneity.Comment: 16 pages, 21 figures. Associated data is available under https://doi.org/10.5281/zenodo.552521

Correlation of dynamic contrast-enhanced bone perfusion with morphologic ultra-short echo time MR imaging in medication-related osteonecrosis of the jaw

OBJECTIVES: To investigate whether dynamic contrast-enhanced (DCE)-MR bone perfusion could serve as surrogate for morphologic ultra-short echo time (UTE) bone images and to correlate perfusion with morphologic hallmarks in histologically proven foci of medication-related osteonecrosis of the jaw (MRONJ). METHODS: Retrospective study including 20 patients with established diagnosis of MRONJ. Qualitative consensus assessment of predefined jaw regions by two radiologists was used as reference standard using Likert scale (0-3) for standard imaging hallmarks in MRONJ (osteolysis, sclerosis, periosteal thickening). DCE-MRI measurements performed in corresponding regions of the mandible were then correlated with qualitative scores. Regions were grouped into "non-affected" and "pathologic" based on binarized Likert scores of different imaging hallmarks (0-1 vs 2-3). DCE-MRI measurements among hallmarks were compared using Mann-Whitney-U-testing. ROC (receiver-operating-characteristic) analysis was performed for each of the perfusion parameters to assess diagnostic performance for identification of MRONJ using morphologic ratings as reference standard. RESULTS: Median perfusion measurements of "pathologic" regions in wash-in, peak enhancement intensity and integrated area under the curve are significantly higher than those of "non-affected" regions, irrespective of reference imaging hallmark (p < 0.05). No significant perfusion differences were found between "pathologic" regions with and without osteolysis (p = 0.180). ROC analysis showed fair diagnostic performance of DCE-MRI parameters for identification of MRONJ (AUC 0.626-0.727). CONCLUSIONS: DCE bone perfusion parameters are significantly increased in MRONJ compared to non-affected regions, irrespective of osteolysis. Due to certain overlap DCE-MRI bone perfusion cannot serve as full surrogate for UTE bone imaging but may enhance reader confidence

Zeitverwendung im Alltag: Zusatzinstrumente zum ifb-Zeitverwendungstagebuch

Die vorliegenden Instrumente zur Messung der Zeitverwendung im Alltag wurden im Rahmen des DFG geförderten Projekts "Innerfamiliale Arbeitsteilung als Prozess" entwickelt und als Kontrollinstrument und potenzielle methodologische Alternative zum ifb-Zeitverwendungstagebuch im Frühjahr 2005 erstmalig im Rahmen von Paarbefragungen (n = 98 Personen) getestet. Die Zielsetzung dieses Vorhabens war es, ein innovatives Erhebungsinstrument zur Messung der Arbeitsteilung von Paaren im Beziehungsverlauf zu entwickeln. Das vorliegende Dokument enthält die Zusatzinstrumente (1) Standarddemografie, (2) Zeitschätzung und (3) Einschätzung der Aufgabenteilung (TPI). (ICI2

Tijdbesteding in het leven van alledag: das ifb-Zeitverwendungstagebuch (niederländische Übersetzung)

Dieser Materialienband enthält die niederländische Übersetzung des ifb-Zeitverwendungstagebuches (ifb-Materialien 3/2005). Die Übersetzung wurde erstellt von Ida van der Woude

Zeitverwendung im Alltag: das ifb-Zeitverwendungstagebuch

Das Dokument enthält das ifb-Zeitverwendungstagebuch, welches im Rahmen des DFG-Projekts "Innerfamiliale Arbeitsteilung als Prozess" entstand. Gegenstand dieser Untersuchung ist der Prozess der familialen Arbeitsteilung in der Beziehungs- und Familienentwicklung. Das Forschungsprojekt greift dabei auf Theorien der kontext- und situationsbezogenen (Wahl-)Handlungen interdependenter Akteure zurück und versucht nicht nur die Entwicklung von Umfang und Art der geschlechtsspezifischen Tätigkeiten quantitativ im Längsschnitt zu bestimmen, sondern auch die damit verbundenen dynamischen Entscheidungsprozesse qualitativ zu entschlüsseln. (ICI2