21,837 research outputs found
Synthetic Generation of Events for Address-Event-Representation Communications
Address-Event-Representation (AER) is a communications protocol
for transferring images between chips, originally developed for bio-inspired
image processing systems. Such systems may consist of a complicated
hierarchical structure with many chips that transmit images among them in real
time, while performing some processing (for example, convolutions). In
developing AER based systems it is very convenient to have available some
kind of means of generating AER streams from on-computer stored images. In
this paper we present a method for generating AER streams in real time from
images stored in a computer’s memory. The method exploits the concept of
linear feedback shift register random number generators. This method has been
tested by software and compared to other possible algorithms for generating
AER streams. It has been found that the proposed method yields a minimum
error with respect to the ideal situation. A hardware platform that exploits this
technique is currently under development
Using simulation studies to evaluate statistical methods
Simulation studies are computer experiments that involve creating data by
pseudorandom sampling. The key strength of simulation studies is the ability to
understand the behaviour of statistical methods because some 'truth' (usually
some parameter/s of interest) is known from the process of generating the data.
This allows us to consider properties of methods, such as bias. While widely
used, simulation studies are often poorly designed, analysed and reported. This
tutorial outlines the rationale for using simulation studies and offers
guidance for design, execution, analysis, reporting and presentation. In
particular, this tutorial provides: a structured approach for planning and
reporting simulation studies, which involves defining aims, data-generating
mechanisms, estimands, methods and performance measures ('ADEMP'); coherent
terminology for simulation studies; guidance on coding simulation studies; a
critical discussion of key performance measures and their estimation; guidance
on structuring tabular and graphical presentation of results; and new graphical
presentations. With a view to describing recent practice, we review 100
articles taken from Volume 34 of Statistics in Medicine that included at least
one simulation study and identify areas for improvement.Comment: 31 pages, 9 figures (2 in appendix), 8 tables (1 in appendix
Synthetic generation of address-events for real-time image processing
Address-event-representation (AER) is a communication protocol that emulates the nervous system's neurons communication, and that is typically used for transferring images between chips. It was originally developed for bio-inspired and real-time image processing systems. Such systems may consist of a complicated hierarchical structure with many chips that transmit images among them in real time, while performing some processing. In this paper several software methods for generating AER streams from images stored in a computer's memory are presented. A hardware version that works in real-time is also being studied. All of them have been evaluated and compared.Comisión Europea IST-2001-34102
Hybrid computer Monte-Carlo techniques
Hybrid analog-digital computer systems for Monte Carlo method application
Design of strapdown gyroscopes for a dynamic environment Interim scientific report
Error analysis for single degree of freedom integrating gyro, and figure of merit relating gyro errors to orientation error of strapdown inertial reference syste
Development of a GPU-based Monte Carlo dose calculation code for coupled electron-photon transport
Monte Carlo simulation is the most accurate method for absorbed dose
calculations in radiotherapy. Its efficiency still requires improvement for
routine clinical applications, especially for online adaptive radiotherapy. In
this paper, we report our recent development on a GPU-based Monte Carlo dose
calculation code for coupled electron-photon transport. We have implemented the
Dose Planning Method (DPM) Monte Carlo dose calculation package (Sempau et al,
Phys. Med. Biol., 45(2000)2263-2291) on GPU architecture under CUDA platform.
The implementation has been tested with respect to the original sequential DPM
code on CPU in phantoms with water-lung-water or water-bone-water slab
geometry. A 20 MeV mono-energetic electron point source or a 6 MV photon point
source is used in our validation. The results demonstrate adequate accuracy of
our GPU implementation for both electron and photon beams in radiotherapy
energy range. Speed up factors of about 5.0 ~ 6.6 times have been observed,
using an NVIDIA Tesla C1060 GPU card against a 2.27GHz Intel Xeon CPU
processor.Comment: 13 pages, 3 figures, and 1 table. Paper revised. Figures update
Analog, hybrid, and digital simulation
Analog, hybrid, and digital computerized simulation technique
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