Fatigue fracture in ductile materials, e. g. metals, is caused by cyclic plasticity. Especially regarding the high numbers of load cycles, plastic material models resolving the full loading path are ...computationally very demanding. Herein, a model with particularly small computational effort is presented. It provides a macroscopic, phenomenological description of fatigue fracture by combining the phase-field method for brittle fracture with a classic durability concept. A local lifetime variable is obtained, which degrades the fracture resistance progressively. By deriving the stress-strain path from cyclic material characteristics, only one increment per load cycle is needed at maximum. The model allows to describe fatigue crack initiation, propagation and residual fracture and can reproduce Paris behaviour.
De novo assembly is a widely used methodology in bioinformatics. However, the conventional short-read based de novo assembly is incapable of reliably reconstructing the large-scale structures of ...human genomes. Recently, a novel optical label based technology has enabled reliable large-scale de novo assembly. Despite its advantage in large-scale genome analysis, this new technology requires a more computationally intensive alignment algorithm than its conventional counterpart. For example, the run-time of reconstructing a human genome is on the order of 10; 000 hours on a sequential CPU. Therefore, in order to practically apply this new technology in genome research, accelerated approaches are desirable. In this paper, we present three different accelerated approaches, multi-core CPU, GPU and FPGA. Against the sequential software baseline, our multi-core CPU design achieved a 8.4× speedup while the GPU and FPGA designs achieved 13.6× and 115× speedups respectively. We also reveal the insights of the design space exploration of this new assembly algorithm on these three different devices by comparing the results.
The purpose of this receiver operating characteristic study was to compare diagnostic efficacy with images displayed on monitors of varying spatial resolutions and maximum luminance levels to that ...with storage phosphor radiographic hard copies.
Seven types of simulated lesions were superimposed onto an anthropomorphic chest phantom. Images were viewed by five radiologists on a 2,560 x 2,048 pixel monitor (maximum luminance, 75 foot-lamberts), on two 1,024 x 1,024 monitors with maximum luminance levels of 25 foot-lamberts and 75 foot-lamberts, respectively, as well as on hard copies. Monitor images were viewed both without and with systematic magnification.
Overall visualization of the lesions was best on hard copies, but visualization on the 2,560 x 2,048 monitor was not found to be substantially different. Lines, reticular opacifications, and catheters were found to be particularly poorly visualized with the 1,024 x 1,024 monitor. These results could be statistically significantly improved only with a systematic magnification; however, this involved a considerable increase in viewing time. Observer performance was markedly inferior with the 1,024 x 1,024 monitor with the lower luminance.
Diagnostic performance with a 1,024 x 1,024 monitor is statistically significantly inferior to that with hard copies. A statistically significant improvement can be achieved with a high-resolution 2,560 x 2,048 monitor with a maximum luminance of 75 foot-lamberts.
In the present paper we investigate the application of differentiable kernel for generalized matrix learning vector quantization as an alternative kernel-based classifier, which additionally provides ...classification dependent data visualization. We show that the concept of differentiable kernels allows a prototype description in the data space but equipped with the kernel metric. Moreover, using the visualization properties of the original matrix learning vector quantization we are able to optimize the class visualization by inherent visualization mapping learning also in this new kernel-metric data space.
The contribution describes the application of the Team 'Computational Intelligence Group' from the University of Applied Sciences Mittweida (Germany) to the ICMLA Face Recognition Challenge 2012. In ...particular we explain the data preprocessing and feature extraction, which was applied before classification learning. Further we give details about the used classification algorithm - the enhanced generalized matrix learning vector quantization model (eGMLVQ). We provide information about the results as well as observed classification properties detected by the learning algorithm.
Access control for a Smart Grid SOA Jung, M.; Hofer, T.; Dobelt, S. ...
2012 International Conference for Internet Technology and Secured Transactions,
2012-Dec.
Conference Proceeding
In the future Smart Grid numerous stakeholders within the electric power grid need to exchange information in order to realize applications like customer energy feedback, billing and invoicing of ...variable tariffs, demand side management and efficient charging of electric vehicles. Using a Service-oriented Architecture (SOA) based on Web services promises a convenient way to provide a data infrastructure capable to realize the required interactions in a flexible way. A main concern in such an architecture is how access to data can be controlled in order to prevent security or privacy violations. Access control depends strongly on authentication and authorization mechanisms. Therefore this paper contributes i) a SOA for the Smart Grid and ii) an access control mechanism that is taken into consideration from the early beginning of the system design. Furthermore, a proof of concept implementation and a scalability analysis are used to investigate the requirements on computational resources in a large scale deployment.
the objective of this ROC-study was to evaluate the diagnostic efficacy of images acquired with a grid in digital selenium radiography compared to that on images obtained with the integrated air gap ...only.
seven types of simulated lesions were superimposed onto an anthropomorphic chest phantom. Selenium radiography images were obtained either with or without an additional antiscatter grid. For images acquired with a grid either a similar or increased exposure level was used. Both normal and obese patients were simulated.
When a grid was used with an equivalent detector dose and a higher exposure, diagnostic performance was significantly improved as compared to images obtained with only the air gap. ROC curve areas for mediastinal nodules and catheters were substantially higher for images acquired with a grid and the same exposure level compared to images obtained without a grid. However, detection of linear, net-shaped and reticulonodular structures in peripheral lung regions was significantly worse when a grid was used with an equivalent exposure level. Concerning the interpretation of images obtained from the normal and obese phantom models, no substantial differences were observed.
a marked improvement in diagnostic performance could be achieved by means of the use of an additional antiscatter grid and an equivalent detector dose. However, when the same exposure was used, images acquired with the grid allowed a better detection of mediastinal structures although a worse performance was evident in radiolucent lung regions. Therefore, the routine use of a grid without increased exposure is not recommended.
At crystallization temperatures of about 800°C bismuth layered oxide SrBi
2
Ta
2
O
9
(SBT) deposited by MOD develops good ferroelectric properties for use in FeRAM devices. But scaling down the film ...thickness of SBT below 150 nm only shorts are measured at this crystallization temperture after top electrode deposition. Working Pt/SBT/Pt-capacitors are achieved by reducing the crystallization temperature. Also temperatures of 800°C are too high for integration of the SBT module in a stacked capacitor architecture for high density memory devices. Therefore, a process is needed to reduced the crystllization temperature of SBT, called "Low Temperature Process".
In this work the electric properties of spin-on processed SBT crystallized in a temperature window from 650°C up to 800°C are investigated. As shown by XRD, transtion of the nonferroelectric Fluorite phase to the Aurivillius phase takes place at approximately 625°C. Increasing the cystallization temperature gives better crystaallized SBT films with bigger SBT graains. However, film prosity is also increasing with temperature. Electrical results of stoichiometric variations of SBT are presented. SEM pictures show that cluster formation is correlated with less film porosity at lower temperatures.
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