8,246 research outputs found
Some initial results and observations from a series of trials within the Ofcom TV White Spaces pilot
A Congeries of Absorption Cross Sections for Wavelengths Less Than 3000 degrees Angstrom
The absorption of ultraviolet solar radiation is of prime importance for the study of planetary atmospheres.The absorption coefficients of most of the atmospheric gases have been measured by a number of investigators, but the results are scattered throughout the literature. This report contains a detailed collection of absorption cross sections of the gases listed in Table 1 for wavelengths less than 3000 degrees angstroms. The data on each gas are given together with a historical sketch of the study of the gas and a list of the pertinent references. Also included is a study of the absorption and photoionization coefficients of the major atmospheric gases at intense solar emission lines
Partitioning Method for Emergent Behavior Systems Modeled by Agent-Based Simulations
Used to describe some interesting and usually unanticipated pattern or behavior, the term emergence is often associated with time-evolutionary systems comprised of relatively large numbers of interacting yet simple entities. A significant amount of previous research has recognized the emergence phenomena in many real-world applications such as collaborative robotics, supply chain analysis, social science, economics and ecology. As improvements in computational technologies combined with new modeling paradigms allow the simulation of ever more dynamic and complex systems, the generation of data from simulations of these systems can provide data to explore the phenomena of emergence.
To explore some of the modeling implications of systems where emergent phenomena tend to dominate, this research examines three simulations based on familiar natural systems where each is readily recognized as exhibiting emergent phenomena. To facilitate this exploration, a taxonomy of Emergent Behavior Systems (EBS) is developed and a modeling formalism consisting of an EBS lexicon and a formal specification for models of EBS is synthesized from the long history of theories and observations concerning emergence. This modeling formalism is applied to each of the systems and then each is simulated using an agent-based modeling framework.
To develop quantifiable measures, associations are asserted: 1) between agent-based models of EBS and graph-theoretical methods, 2) with respect to the formation of relationships between entities comprising a system and 3) concerning the change in uncertainty of organization as the system evolves.
These associations form the basis for three measurements related to the information flow, entity complexity, and spatial entropy of the simulated systems. These measurements are used to: 1) detect the existence of emergence and 2) differentiate amongst the three systems.
The results suggest that the taxonomy and formal specification developed provide a workable, simulation-centric definition of emergent behavior systems consistent with both historical concepts concerning the emergence phenomena and modern ideas in complexity science. Furthermore, the results support a structured approach to modeling these systems using agent-based methods and offers quantitative measures useful for characterizing the emergence phenomena in the simulations
Accommodation requirements for microgravity science and applications research on space station
Scientific research conducted in the microgravity environment of space represents a unique opportunity to explore and exploit the benefits of materials processing in the virtual abscence of gravity induced forces. NASA has initiated the preliminary design of a permanently manned space station that will support technological advances in process science and stimulate the development of new and improved materials having applications across the commercial spectrum. A study is performed to define from the researchers' perspective, the requirements for laboratory equipment to accommodate microgravity experiments on the space station. The accommodation requirements focus on the microgravity science disciplines including combustion science, electronic materials, metals and alloys, fluids and transport phenomena, glasses and ceramics, and polymer science. User requirements have been identified in eleven research classes, each of which contain an envelope of functional requirements for related experiments having similar characteristics, objectives, and equipment needs. Based on these functional requirements seventeen items of experiment apparatus and twenty items of core supporting equipment have been defined which represent currently identified equipment requirements for a pressurized laboratory module at the initial operating capability of the NASA space station
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I-Xe analysis of a magnetic separate from Lodranite GRA95209
I-Xe dating of a magnetic mineral separate from lodranite GRA95209 suggests that peak temperatures (and therefore melt migration) occurred early, at least a few million years before closure of the I-Xe system in phosphates from Acapulco
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Is caseloading sustainable? Lessons from the front line at King’s College Hospital
At King’s College Hospital in Camberwell, south London, we have a 25 year tradition of NHS caseloading, with named midwives providing continuity for all antenatal, intrapartum and postnatal care for women and their families (Wiseman & Holland 2018). Caseloading midwives care for 900-1,000 mixed-risk women each year, about 18% of King’s 5000-5,500 births.
In this article we describe the experience of caseloading from the perspective of the 30 midwives at King’s working in this way, and we have included their voices here, as well as those of local women who have received caseloading care. We discuss how we organise our teams and how we coped with the challenge of major organisational change. Finally, we reflect on our outcomes and what contributes to the sustainability of the caseloading model
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Is caseloading sustainable? The 25-year history of caseloading at King’s College Hospital
Caseload midwifery is defined as follows:
When a midwife carries a caseload she is the primary provider of midwifery care (the named midwife) during pregnancy, birth and the early postnatal days for an agreed number of women. She may be providing care to women wherever they are: at home, in the community or in a maternity unit. She has responsibility for the planning and monitoring of care throughout for the women on her list. She liaises with medical colleagues and social agencies as appropriate. (National Childbirth Trust 1995)
Caseloading is a relational model of care provided by a small team of midwives who do on-calls in order to provide a 24/7 service. Midwives have autonomy over their workload, allowing them to respond to the individual needs of women and their families. Mixed-risk caseloading has been an important element of maternity care at King’s College Hospital for twenty-five years, where currently almost 20% of the 5-6,000 women who give birth there each year receive caseloading care. In this two-part article, we discuss how caseloading was developed at King’s, how the model works, the outcomes and what contributes to the sustainability of this model of care
Quantum Kinetic Theory III: Simulation of the Quantum Boltzmann Master Equation
We present results of simulations of a em quantum Boltzmann master equation
(QBME) describing the kinetics of a dilute Bose gas confined in a trapping
potential in the regime of Bose condensation. The QBME is the simplest version
of a quantum kinetic master equations derived in previous work. We consider two
cases of trapping potentials: a 3D square well potential with periodic boundary
conditions, and an isotropic harmonic oscillator. We discuss the stationary
solutions and relaxation to equilibrium. In particular, we calculate particle
distribution functions, fluctuations in the occupation numbers, the time
between collisions, and the mean occupation numbers of the one-particle states
in the regime of onset of Bose condensation.Comment: 12 pages, 15 figure
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