4,287 research outputs found
Inherent uncertainties in meteorological parameters for wind turbine design
Major difficulties associated with meteorological measurments such as the inability to duplicate the experimental conditions from one day to the next are discussed. This lack of consistency is compounded by the stochastic nature of many of the meteorological variables of interest. Moreover, simple relationships derived in one location may be significantly altered by topographical or synoptic differences encountered at another. The effect of such factors is a degree of inherent uncertainty if an attempt is made to describe the atmosphere in terms of universal laws. Some of these uncertainties and their causes are examined, examples are presented and some implications for wind turbine design are suggested
A Superfield for Every Dash-Chromotopology
The recent classification scheme of so-called adinkraic off-shell
supermultiplets of N-extended worldline supersymmetry without central charges
finds a combinatorial explosion. Completing our earlier efforts, we now
complete the constructive proof that all of these trillions or more of
supermultiplets have a superfield representation. While different as
superfields and supermultiplets, these are still super-differentially related
to a much more modest number of minimal supermultiplets, which we construct
herein.Comment: 13 pages, integrated illustration
Conformal fixed point, Cosmological Constant and Quintessence
We connect a possible solution for the ``cosmological constant problem'' to
the existence of a (postulated) conformal fixed point in a fundamental theory.
The resulting cosmology leads to quintessence, where the present acceleration
of the expansion of the universe is linked to a crossover in the flow of
coupling constants.Comment: More detailed discussion of quantum fluctuations,update with
WMAP-data,4 pages,LaTe
Recommended from our members
Assessing time knowledge in children aged 10 to 11 years
The acquisition of time knowledge involves learning how to read clocks, estimate time, read dates and learn about temporal sequences. Evidence suggests that many of these competencies are acquired by 10 years of age although not all children may follow this developmental path. The main purpose of this study was to collect normative data for a screening tool that assesses time knowledge. These data identify the prevalence and pattern of difficulties with time knowledge among a UK sample of Year 6 pupils (aged 10 to 11 years). The Time Screening Assessment tool (Doran, Dutt & Pembery, 2015), designed to assess time knowledge, was administered individually to a sample of 79 children. Findings revealed a median overall score of 32 out of a maximum score of 36. 25% of children performed at or close to ceiling, however seven children scored more than -1.5 standard deviations below the mean. The value of these findings to practitioners working with children in schools is discussed
Community information of 233 middle grade children
Thesis (M.A.)--Boston University, 1949. This item was digitized by the Internet Archive
Effectiveness of Team Member Education on Fall Prevention Techniques, Management of Dementia-Related Behaviors, and Safe Transfer Completion
Introduction: There is a significant need to address fall prevention in memory care/assisted living homes due to the high prevalence of falls that occur in these settings. Managing dementia-related behaviors and completing safe transfers support fall prevention in dementia populations. Fall prevention was expressed as a major need by BeeHive Homes of Mount Horeb, a memory care specific assisted living home that served as the community partner for this quality improvement project.
Purpose: The quality improvement project provided education and training to team members working at BeeHive Homes of Mount Horeb on safe transfer completion, management of dementia-related behaviors, and fall prevention techniques.
Approach: New training, handout packets, and videos were created throughout this experience as well as hands-on training provided to team members. A survey was created to evaluate the effectiveness of the education and training provided to team members.
Results: All survey results were positive. As well as creating a survey, fall incident reports were obtained and results yielded a decrease in falls through the progression of the quality improvement project.
Recommendations: Increasing the organization of team member training, maintaining an adequate supply of gait belts, having strong team member to resident staffing ratios, and making required environmental changes will all continue to support fall prevention at BeeHive Homes of Mount Horeb
Matrix Transfer Function Design for Flexible Structures: An Application
The application of matrix transfer function design techniques to the problem of disturbance rejection on a flexible space structure is demonstrated. The design approach is based on parameterizing a class of stabilizing compensators for the plant and formulating the design specifications as a constrained minimization problem in terms of these parameters. The solution yields a matrix transfer function representation of the compensator. A state space realization of the compensator is constructed to investigate performance and stability on the nominal and perturbed models. The application is made to the ACOSSA (Active Control of Space Structures) optical structure
Traction drive system design considerations for a lunar roving vehicle
Optimum design considerations of traction drive for lunar roving vehicl
Early Dark Energy Cosmologies
We propose a novel parameterization of the dark energy density. It is
particularly well suited to describe a non-negligible contribution of dark
energy at early times and contains only three parameters, which are all
physically meaningful: the fractional dark energy density today, the equation
of state today and the fractional dark energy density at early times. As we
parameterize Omega_d(a) directly instead of the equation of state, we can give
analytic expressions for the Hubble parameter, the conformal horizon today and
at last scattering, the sound horizon at last scattering, the acoustic scale as
well as the luminosity distance. For an equation of state today w_0 < -1, our
model crosses the cosmological constant boundary. We perform numerical studies
to constrain the parameters of our model by using Cosmic Microwave Background,
Large Scale Structure and Supernovae Ia data. At 95% confidence, we find that
the fractional dark energy density at early times Omega_early < 0.06. This
bound tightens considerably to Omega_early < 0.04 when the latest Boomerang
data is included. We find that both the gold sample of Riess et. al. and the
SNLS data by Astier et. al. when combined with CMB and LSS data mildly prefer
w_0 < -1, but are well compatible with a cosmological constant.Comment: 6 pages, 3 figures; references added, matches published versio
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