545 research outputs found
Asymptotic Behavior of the Einstein-Yang-Mills-Dilaton System for a Closed Friedmann-Lemaitre Universe
We study the coupled Einstein-Yang-Mills-Dilaton (EYMD) equations for a
Fried\-mann-Le\-mai\-tre universe with constant curvature . Our detailed
analysis is restricted to the case where the dilaton potential and the
cosmological constant vanish. Also assuming a static gauge field, we present
analytical and numerical results on the behavior of solutions of the EYMD
equations. For different values of the dilaton coupling constant we analyze the
phase portrait for the time evolution of the dilaton field and give the
behavior of the scale factor. It turns out that there are no inflationary
stages in this model.Comment: 18 pages, Uuencoded gzip compressed tar file containing a latex file
and 12 figures. The epsfig.sty is neede
Being a choice architect in project management: the Galp energy example
In a world where managing projects is a difficult task that requires several skills to succeed, several authors studied ways to prevent a project from deviation of its desired final outcome.
This works intends to study the Choice Architecture tools presented in the book ―Nudge‖, through the development of an internal project at GALP energy, to present some key points to assess before its development, related with the need to manage the environment in which the stakeholders will work on the project. The main idea consists in preventing some behaviors and decisions that could lead the project development away from a desired outcome. Managing that environment where the choices are made is known as being a Choice Architect.
To begin, this work will focus in knowing the company GALP energy, and where specifically the project progress.
Once the global environment understood, the main project objective is unveiled, explaining the problem to be solved, the research done to solve it and how can the choice architecture be applied.
Afterward, a specific study is presented on the way the choice architecture contributed for the final solution, justifying the importance on knowing how the brain work, and how the decision biases and heuristics can contribute for the choice architecture successful influence on the elaboration and protection of a project desired solution.
To conclude, the project final result and the experience obtained from this work are explained justifying the reason that made this project to be considered a success by several persons. The reason of success is given in the end by the key clients and persons involved in the process
Settlement patterns of corals and other benthos on reefs with divergent environments and disturbances histories around the northeastern Arabian Peninsula
Larval supply is a principal factor determining the establishment, structure, and diversity of sessile benthic assemblages on coral reefs. Benthic reef communities in north-eastern Arabia have been subject to recurrent disturbances in recent years, and subsequent recovery will be, in part, driven by variation in the supply of available colonists. Using settlement tiles deployed seasonally over 1 year at eight sites encompassing three environmentally divergent regions (southern Arabian Gulf, the Musandam Peninsula in the Strait of Hormuz, and the Sea of Oman) we assessed spatial and seasonal variability in settlement of benthic reef organisms. There was strong spatial variation in composition of new colonists among regions, mainly driven by the high abundance of coralline algae in the Arabian Gulf, colonial ascidians on the Musandam Peninsula and barnacles in the Sea of Oman. Seasonal differences in composition of new colonists were less important than regional differences, with seasonal variation in settlement not consistent among regions. The number of corals settling to the tiles was low compared to those reported for other regions, with mean densities ranging from 0 corals m -2 year -1 in the Sea of Oman to 30 (± 0.6 SE) and 38 (± 0.5 SE) in Musandam and the Arabian Gulf, respectively. Peak coral settlement abundance in the Gulf occurred in summer and autumn and in Musandam in spring (averaging 82 and 70 settlers m -2 year -1 , respectively, during the peak settlement season). This work provides the first record of large-scale spatial and seasonal patterns of settlement in north-eastern Arabia and provides valuable information on the supply of settlers available to recolonize heavily disturbed reefs in this region. The extremely low rates of coral settlement suggest that these marginal reefs are likely to be extremely slow to recover from on-going and future disturbances
Monitoring feet temperature using thermography
Studies show that regular monitoring of feet temperature may limit the incidence of disabling conditions such as foot ulcers and lower-limb amputations. Infrared thermometry and liquid crystal thermography were identified as the leading technologies in use today. In this study, we analysed the maximum temperature and tested some mathematical models for the foot temperature distribution
Mathematical model of feet temperature
In this work it is consider the problem of finding the best approximation to characterize the feet temperature
distribution. For this study it was consider the nonlinear least squares technique, combined with penalty method, to identify
the function that approximate better the data obtained through thermographic images. The preliminary results indicate that the
best function approximation is based on trigonometric sums
Modelação matemática da variação da temperatura no pé
Este trabalho tem como objectivo principal a modelação matemática da distribuição da temperatura
em pés em pessoas saudáveis. Para tal, consideram-se imagens térmicas da planta dos pés de quinze
voluntários entre os 21 e 43 anos.
As imagens obtidas através da câmara térmica FLIR 365, foram processadas utilizando duas técnicas
de processamento de imagens distintas: a técnica de Region Growing e Watershad. Neste procedimento
conclui-se que se obtinha melhores resultados usando a técnica de Region Growing, obtendo-se
a matriz da distribuição da temperatura de cada pé.
Com a matriz obtida, usando a técnica descrita anteriormente, foram testadas cinco modelações
diferentes combinadas com cinco técnicas de optimização não linear.
Dos resultados obtidos pode-se concluir que as melhores modelações são baseadas na soma de
quadrados de funções trigonométricas. The main objective of this work is to find a mathematical model of temperature distribution in feet in
healthy people. We consider feet thermal images of fifteen volunteers between 21 and 43 years.
The images obtained though the thermal camera FLIR 365, were processed using two diferent
image processing techniques: the techique of Region Growing and Watershad. In this procedure, it
was concluded that better results are obtained using the technique of Region Growing to obtain the
matrix of temperature distribution of each foot.
With the temperature distribution matrix, obtained using the technique described above, were
tested five different modeling combined with five nonlinear optimization techniques.
From our results, we can conclude that the best modeling is based on the sum of squares of
trigonometric functions.
In terms of professional practice in construction in Portugal, the graduate professionals are architects, civil engineers and technical civil engineers. In order to legally practise in the field, architects must be registered in the Order of Architects, civil engineers with the Order of Engineers and technical civil engineers with the Professional Association of Technical Engineers. The legal framework for the activity of these different professions has long been established by the Decree Law 73/1973. As regards the construction management profession, these professionals are not obliged by law to fulfil any specific educational requirements nor are they subject to any legal regime regulating their activities. However, it is generally recognised that the Institutions of Higher Education in Portugal do not provide the competencies required for an efficient practice in the area of construction management.
The Bologna Model establishes that the definition of the objectives of the course subjects be centred in terms of the learning outcomes. It appears that with the new curricula structure, which emphasises competencies to be acquired, the institutions of higher education are better prepared to mach their educational activities with the needs of business community
Monitoring feet temperature using thermography
Studies show that regular monitoring of feet temperature may limit the incidence of disabling conditions such as foot ulcers and lower-limb amputations. Infrared thermometry and liquid crystal thermography were identified as the leading technologies in use today. In this study, we analysed the maximum temperature and tested some mathematical models for the foot temperature distribution
Halo Properties in Cosmological Simulations of Self-Interacting Cold Dark Matter
We present a comparison of halo properties in cosmological simulations of
collisionless cold dark matter (CDM) and self-interacting dark matter (SIDM)
for a range of dark matter cross sections. We find, in agreement with various
authors, that CDM yields cuspy halos that are too centrally concentrated as
compared to observations. Conversely, SIDM simulations using a Monte Carlo
N-body technique produce halos with significantly reduced central densities and
flatter cores with increasing cross section. We introduce a concentration
parameter based on enclosed mass that we expect will be straightforward to
determine observationally, unlike that of Navarro, Frenk & White, and provide
predictions for SIDM and CDM. SIDM also produces more spherical halos than CDM,
providing possibly the strongest observational test of SIDM. We discuss our
findings in relation to various relevant observations as well as SIDM
simulations of other groups. Taking proper account of simulation limitations,
we find that a dark matter cross section per unit mass of sigma_DM ~=
10^{-23}-10^{-24} cm^2/GeV is consistent with all current observational
constraints.Comment: 14 pages, submitted to Ap
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