8,190 research outputs found
A comparison of two position estimate algorithms that use ILS localizer and DME information. Simulation and flight test results
Simulation and flight tests were conducted to compare the accuracy of two algorithms designed to compute a position estimate with an airborne navigation computer. Both algorithms used ILS localizer and DME radio signals to compute a position difference vector to be used as an input to the navigation computer position estimate filter. The results of these tests show that the position estimate accuracy and response to artificially induced errors are improved when the position estimate is computed by an algorithm that geometrically combines DME and ILS localizer information to form a single component of error rather than by an algorithm that produces two independent components of error, one from a DMD input and the other from the ILS localizer input
Understanding Student Computational Thinking with Computational Modeling
Recently, the National Research Council's framework for next generation
science standards highlighted "computational thinking" as one of its
"fundamental practices". 9th Grade students taking a physics course that
employed the Modeling Instruction curriculum were taught to construct
computational models of physical systems. Student computational thinking was
assessed using a proctored programming assignment, written essay, and a series
of think-aloud interviews, where the students produced and discussed a
computational model of a baseball in motion via a high-level programming
environment (VPython). Roughly a third of the students in the study were
successful in completing the programming assignment. Student success on this
assessment was tied to how students synthesized their knowledge of physics and
computation. On the essay and interview assessments, students displayed unique
views of the relationship between force and motion; those who spoke of this
relationship in causal (rather than observational) terms tended to have more
success in the programming exercise.Comment: preprint to submit to PERC proceedings 201
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Factors influencing the utilisation of free-standing and alongside midwifery units in England: a qualitative research study
OBJECTIVE: To identify factors influencing the provision, utilisation and sustainability of midwifery units (MUs) in England.
DESIGN: Case studies, using individual interviews and focus groups, in six National Health Service (NHS) Trust maternity services in England.
SETTING AND PARTICIPANTS: NHS maternity services in different geographical areas of England Maternity care staff and service users from six NHS Trusts: two Trusts where more than 20% of all women gave birth in MUs, two Trusts where less than 10% of all women gave birth in MUs and two Trusts without MUs. Obstetric, midwifery and neonatal clinical leaders, managers, service user representatives and commissioners were individually interviewed (n=57). Twenty-six focus groups were undertaken with midwives (n=60) and service users (n=52).
MAIN OUTCOME MEASURES: Factors influencing MU use.
FINDINGS: The study findings identify several barriers to the uptake of MUs. Within a context of a history of obstetric-led provision and lack of decision-maker awareness of the clinical and economic evidence, most Trust managers and clinicians do not regard their MU provision as being as important as their obstetric unit (OU) provision. Therefore, it does not get embedded as an equal and parallel component in the Trust's overall maternity package of care. The analysis illuminates how implementation of complex interventions in health services is influenced by a range of factors including the medicalisation of childbirth, perceived financial constraints, adequate leadership and institutional norms protecting the status quo.
CONCLUSIONS: There are significant obstacles to MUs reaching their full potential, especially free-standing midwifery units. These include the lack of commitment by providers to embed MUs as an essential service provision alongside their OUs, an absence of leadership to drive through these changes and the capacity and willingness of providers to address women's information needs. If these remain unaddressed, childbearing women's access to MUs will continue to be restricted
Immorality and Irrationality
Does immorality necessarily involve irrationality? The question is often taken to be among the deepest in moral philosophy. But apparently deep questions sometimes admit of deflationary answers. In this case we can make way for a deflationary answer by appealing to dualism about rationality, according to which there are two fundamentally distinct notions of rationality: structural rationality and substantive rationality. I have defended dualism elsewhere. Here, I’ll argue that it allows us to embrace a sensible – I will not say boring – moderate view about the relationship between immorality and irrationality: roughly, that immorality involves substantive irrationality, but not structural irrationality. I defend this moderate view, and argue that many of the arguments for less moderate views turn either on missing the distinction between substantive and structural rationality, or on misconstruing it
Reply to ‘Evaluation of the effect of JPEG and JPEG2000 image compression on the detection of diabetic retinopathy’
Antiferromagnetism at T > 500 K in the Layered Hexagonal Ruthenate SrRu2O6
We report an experimental and computational study of magnetic and electronic
properties of the layered Ru(V) oxide SrRu2O6 (hexagonal, P-3 1m), which shows
antiferromagnetic order with a N\'eel temperature of 563(2) K, among the
highest for 4d oxides. Magnetic order occurs both within edge-shared octahedral
sheets and between layers and is accompanied by anisotropic thermal expansivity
that implies strong magnetoelastic coupling of Ru(V) centers. Electrical
transport measurements using focused ion beam induced deposited contacts on a
micron-scale crystallite as a function of temperature show p-type
semiconductivity. The calculated electronic structure using hybrid density
functional theory successfully accounts for the experimentally observed
magnetic and electronic structure and Monte Carlo simulations reveals how
strong intralayer as well as weaker interlayer interactions are a defining
feature of the high temperature magnetic order in the material.Comment: Physical Review B 2015 accepted for publicatio
Asymmetries in the Value of Existence
According to asymmetric comparativism, it is worse for a person to exist with a miserable life than not to exist, but it is not better for a person to exist with a happy life than not to exist. My aim in this paper is to explain how asymmetric comparativism could possibly be true. My account of asymmetric comparativism begins with a different asymmetry, regarding the (dis)value of early death. I offer an account of this early death asymmetry, appealing to the idea of conditional goods, and generalize it to explain how asymmetric comparativism could possibly be true. I also address the objection that asymmetric comparativism has unacceptably antinatalist implications
The Robertson v. Princeton Case: Too Important to Be Left to the Lawyers
Offers comments from eleven contributors on the Robertson family's donor rights suit against the Woodrow Wilson School of Public and International Affairs for violation of donor intent. Explores its effects on and implications for the nonprofit sector
Beam alignment techniques based on the current multiplication effect in photoconductors Third summary technical progress report, 15 Nov. 1966 - 15 Oct. 1967
Beam alignment techniques developed for infrared sensitive single crystal germanium to study multiplication effect in photoconductor
Factors influencing utilisation of ‘free-standing’ and ‘alongside’ midwifery units for low-risk births in England: a mixed-methods study
Background
Midwifery-led units (MUs) are recommended for ‘low-risk’ births by the National Institute for Health and Care Excellence but according to the National Audit Office were not available in one-quarter of trusts in England in 2013 and, when available, were used by only a minority of the low-risk women for whom they should be suitable. This study explores why.
Objectives
To map the provision of MUs in England and explore barriers to and facilitators of their development and use; and to ascertain stakeholder views of interventions to address these barriers and facilitators.
Design
Mixed methods – first, MU access and utilisation across England was mapped; second, local media coverage of the closure of free-standing midwifery units (FMUs) were analysed; third, case studies were undertaken in six sites to explore the barriers and facilitators that have an impact on the development of MUs; and, fourth, by convening a stakeholder workshop, interventions to address the barriers and facilitators were discussed.
Setting
English NHS maternity services.
Participants
All trusts with maternity services.
Interventions
Establishing MUs.
Main outcome measures
Numbers and types of MUs and utilisation of MUs.
Results
Births in MUs across England have nearly tripled since 2011, to 15% of all births. However, this increase has occurred almost exclusively in alongside units, numbers of which have doubled. Births in FMUs have stayed the same and these units are more susceptible to closure. One-quarter of trusts in England have no MUs; in those that do, nearly all MUs are underutilised. The study findings indicate that most trust managers, senior midwifery managers and obstetricians do not regard their MU provision as being as important as their obstetric-led unit provision and therefore it does not get embedded as an equal and parallel component in the trust’s overall maternity package of care. The analysis illuminates how provision and utilisation are influenced by a complex range of factors, including the medicalisation of childbirth, financial constraints and institutional norms protecting the status quo.
Limitations
When undertaking the case studies, we were unable to achieve representativeness across social class in the women’s focus groups and struggled to recruit finance directors for individual interviews. This may affect the transferability of our findings.
Conclusions
Although there has been an increase in the numbers and utilisation of MUs since 2011, significant obstacles remain to MUs reaching their full potential, especially FMUs. This includes the capacity and willingness of providers to address women’s information needs. If these remain unaddressed at commissioner and provider level, childbearing women’s access to MUs will continue to be restricted.
Future work
Work is needed on optimum approaches to improve decision-makers’ understanding and use of clinical and economic evidence in service design. Increasing women’s access to information about MUs requires further studies of professionals’ understanding and communication of evidence. The role of FMUs in the context of rural populations needs further evaluation to take into account user and community impact.
Funding
This project was funded by the National Institute for Health Research (NIHR) Health Services and Delivery Research programme and will be published in full in Health Services and Delivery Research; Vol. 8, No. 12. See the NIHR Journals Library website for further project information
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