2,409 research outputs found
A new code for Fourier-Legendre analysis of large datasets: first results and a comparison with ring-diagram analysis
Fourier-Legendre decomposition (FLD) of solar Doppler imaging data is a
promising method to estimate the sub-surface solar meridional flow. FLD is
sensible to low-degree oscillation modes and thus has the potential to probe
the deep meridional flow. We present a newly developed code to be used for
large scale FLD analysis of helioseismic data as provided by the Global
Oscillation Network Group (GONG), the Michelson Doppler Imager (MDI)
instrument, and the upcoming Helioseismic and Magnetic Imager (HMI) instrument.
First results obtained with the new code are qualitatively comparable to those
obtained from ring-diagram analyis of the same time series.Comment: 4 pages, 2 figures, 4th HELAS International Conference "Seismological
Challenges for Stellar Structure", 1-5 February 2010, Arrecife, Lanzarote
(Canary Islands
Concentration by sorting : Feasibility determination by radial distribution analysis
A method was developed for determining certain factors for assessing the feasibility of sorting fragments of an inhomogeneous solid to concentrate a species. These factors are the typical size of zones in which the grade exceeds a selected value, and the recovery potentially achievable by sorting fragments of such size --Abstract, page iii
Predictors of Physical Activity among Women in Genesee County between the Ages of 40-60
The pilot study explored factors that Flint area women, between the ages of 40 and 60, cited as influencing their daily physical activity. Better understanding of factors that influence physical activity may lead to more appropriate and effective health promotion messages and programs. In depth interviews were carried out with fifteen women between the ages of 40 and 60 in Genesee County. Qualitative theory guided the interview process and data analysis. Recurring themes from interviews were identified and categorized using the ecological model. Although subjects identified influences on their exercise behavior within each of the five levels of the ecological model (intrapersonal, interpersonal, institutional, community or public policy), women most often cited institutional supports when suggesting ideas for activity promotion. Interventions in the institutional level, such as work-site health promotion, may be most successful to increase physical activity among this cohort.Master'sSchool of Health Professions and Studies: Health EducationUniversity of Michiganhttp://deepblue.lib.umich.edu/bitstream/2027.42/117697/1/Doerr.pd
Runtime Analysis of a Heavy-Tailed Genetic Algorithm on Jump Functions
It was recently observed that the genetic algorithm
can comparably easily escape the local optimum of the jump functions benchmark.
Consequently, this algorithm can optimize the jump function with jump size
in an expected runtime of only fitness
evaluations (Antipov, Doerr, Karavaev (GECCO 2020)). To obtain this
performance, however, a non-standard parameter setting depending on the jump
size was used.
To overcome this difficulty, we propose to choose two parameters of the
genetic algorithm randomly from a power-law
distribution. Via a mathematical runtime analysis, we show that this algorithm
with natural instance-independent choices of the distribution parameters on all
jump functions with jump size at most has a performance close to what the
best instance-specific parameters in the previous work obtained. This price for
instance-independence can be made as small as an factor. Given
the difficulty of the jump problem and the runtime losses from using mildly
suboptimal fixed parameters (also discussed in this work), this appears to be a
fair price.Comment: An extended version of the same-titled paper from PPSN 202
A semantic web approach for built heritage representation
In a built heritage process, meant as a structured system of activities
aimed at the investigation, preservation, and management of architectural
heritage, any task accomplished by the several actors involved in it is deeply
influenced by the way the knowledge is represented and shared. In the current
heritage practice, knowledge representation and management have shown several
limitations due to the difficulty of dealing with large amount of extremely heterogeneous
data. On this basis, this research aims at extending semantic web
approaches and technologies to architectural heritage knowledge management in
order to provide an integrated and multidisciplinary representation of the artifact
and of the knowledge necessary to support any decision or any intervention and
management activity. To this purpose, an ontology-based system, representing
the knowledge related to the artifact and its contexts, has been developed through
the formalization of domain-specific entities and relationships between them
Moving beyond descriptive models: research issues for design and implementation
In this paper, we draw on a models and modeling perspective to describe the design of a sequence of tasks, known as a model development sequence, that has been used to research the teaching and learning of mathematics. A central research goal of a models and modeling perspective is the development of principles for the design of sequences of modeling tasks and for the teaching of such sequences. We extend our earlier research by elaborating how a model development sequence can be used to support students in developing models that are not only descriptive but also have explanatory power when connected to existing mathematical models. In so doing, we elaborate language issues about representations and context as well as the implementation strategies used by the teacher
Searching for Radio Pulsars in 3EG Sources at Urumqi Observatory
Since mid-2005, a pulsar searching system has been operating at 18 cm on the
25-m radio telescope of Urumqi Observatory. Test observations on known pulsars
show that the system can perform the intended task. The prospect of using this
system to observe 3EG sources and other target searching tasks is discussed.Comment: a training project about MSc thesi
- …