6,713 research outputs found
Study of lunar earthshine by photoelectric photometry Final report, 1 Nov. 1965 - 30 Sep. 1967
Design feasibility and performance of semiportable field instrument for monitoring changes in earth albedo via earthshine measurement
The procurement and evaluation of a prototype laser satellite-tracking system Final report, 1 Jan. 1967 - 30 Sep. 1968
Pulsed ruby laser satellite tracking syste
Energy Efficiency of Hybrid-Power HetNets: A Population-like Games Approach
In this paper, a distributed control scheme based on population games is proposed. The controller is in charge of dealing with the energy consumption problem in a Heterogeneous Cellular Network (HetNet) powered by hybrid energy sources (grid and renewable energy) while guaranteeing appropriate quality of service (QoS) level at the same time. Unlike the conventional approach in population games, it considers both atomicity and non-anonymity. Simulation results show that the proposed population-games approach reduces grid consumption by up to about 12% compared to the traditional best-signal level association policy.U.S. Air Force Office of Scientific Research FA9550-17-1-0259Ministerio de Cultura y Deporte DPI2016-76493-C3-3-RMinisterio de Economía y Empresa DPI2017-86918-
A Coalitional Model Predictive Control Approach for Heterogeneous Cellular Networks
Heterogeneous cellular networks (HetNets) are large-scale systems that comprise numerous base stations interacting with a significant number of users of diverse types. Finding a trade-off between energy consumption and quality of service is one of the major challenges in these networks. To deal with this issue, a coalitional model predictive control (MPC) approach is proposed for a HetNet powered by renewable power sources, and compared in simulation with the traditional best-signal level mechanism and the centralized MPC method. Furthermore, other key performance indicators associated with grid consumption such as the number of served users and transmission rates are also evaluated
Development of an Activity Patterns Scale (APS)
Six activity patterns were identified across various self-report measures in participants with chronic pain: Pain Avoidance, Activity Avoidance; Task Contingent Persistence; Excessive Persistence, Pain Contingent Persistence and Pacing (Kindermans et al., 2011). It was proposed that instruments assessing “pacing” should include items addressing one specific pacing behavior (breaking tasks into smaller pieces; taking frequent short rests and speeding up or slowing down) with a single goal (increasing activity level, conserve energy for valued activities and pain reduction) (Nielson et al., 2013).
The aim of the present study was to develop an instrument to assess the activity patterns identified by Kindermans et al. (2011). The instrument also included three pacing scales one for each of the aforementioned goals.
Methods
A sample of 229 patients with fibromyalgia and 62 suffering other rheumatic diseases answered online the APS and the “Patterns of Activity Measure-Pain” (POAM-P) (Cane et al., 2007).
Three alternative factor structures were tested by confirmatory factor analyses performed via structural equation modelling. .
Results
The structure with the best fit had 8 factors corresponding to the hypothesized scales: Pain Avoidance (α=.60), Activity Avoidance (α=.60); Task Contingent Persistence (α=.81); Excessive Persistence (α=.84), Pain Contingent Persistence (α=.70), Pacing for increasing activity (α=.76), Pacing for energy conservation (α=.72) and Pacing for pain reduction (α=.65). The correlations with the POAM-P scales were high and in the postulated direction.
Conclusions
The APS showed adequate reliability and structural validity. According to these results, Avoidance, Persistence and Pacing seem to be multidimensional constructs.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
Photographic measurements of the energy distribution in the beam of a ruby laser
Photographic measurement of energy distribution in beam of Q-switched ruby lase
On the relation between virial coefficients and the close-packing of hard disks and hard spheres
The question of whether the known virial coefficients are enough to determine
the packing fraction at which the fluid equation of state of a
hard-sphere fluid diverges is addressed. It is found that the information
derived from the direct Pad\'e approximants to the compressibility factor
constructed with the virial coefficients is inconclusive. An alternative
approach is proposed which makes use of the same virial coefficients and of the
equation of state in a form where the packing fraction is explicitly given as a
function of the pressure. The results of this approach both for hard-disk and
hard-sphere fluids, which can straightforwardly accommodate higher virial
coefficients when available, lends support to the conjecture that
is equal to the maximum packing fraction corresponding to an ordered
crystalline structure.Comment: 10 pages, 6 figures; v2: discussion about hard-square and
hard-hexagon systems on a lattice added; five new reference
Measurements of satellite range with a ruby laser
Range measurements of GEOS-I and BE-C satellites with ruby lase
- …