4,828 research outputs found
Use of soil moisture information in yield models
There are no author-identified significant results in this report
Cost benefit evaluation of maintenance options for aging equipment using monetised risk values: A practical application
With constant pressure to reduce maintenance costs as well as short-term budget constraints in a changing market environment, asset managers are compelled to continue operating aging assets while deferring maintenance and investment. The scope of the paper is to get an overview of the methods used to evaluate risks and opportunities for deferred maintenance interventions on aging equipment, and underline the importance to include monetised risk considerations and timeline considerations, to evaluate different scenarios connected with the possible options. Monetised risk values offer the opportunity to support risk-based decision-making using the data collected from the field. The paper presents examples of two different methods and their practical applicability in two case studies in the energy sector for a company managing power stations. The use of the existing and the new proposed solutions are discussed on the basis of their applicability to the concrete examples
Clarification of the Bootstrap Percolation Paradox
We study the onset of the bootstrap percolation transition as a model of
generalized dynamical arrest. We develop a new importance-sampling procedure in
simulation, based on rare events around "holes", that enables us to access
bootstrap lengths beyond those previously studied. By framing a new theory in
terms of paths or processes that lead to emptying of the lattice we are able to
develop systematic corrections to the existing theory, and compare them to
simulations. Thereby, for the first time in the literature, it is possible to
obtain credible comparisons between theory and simulation in the accessible
density range.Comment: 4 pages with 3 figure
Legal Judgement Prediction for UK Courts
Legal Judgement Prediction (LJP) is the task of automatically predicting the outcome of a court case given only the case document. During the last five years researchers have successfully attempted this task for the supreme courts of three jurisdictions: the European Union, France, and China. Motivation includes the many real world applications including: a prediction system that can be used at the judgement drafting stage, and the identification of the most important words and phrases within a judgement. The aim of our research was to build, for the first time, an LJP model for UK court cases. This required the creation of a labelled data set of UK court judgements and the subsequent application of machine learning models. We evaluated different feature representations and different algorithms. Our best performing model achieved: 69.05% accuracy and 69.02 F1 score. We demonstrate that LJP is a promising area of further research for UK courts by achieving high model performance and the ability to easily extract useful features
Live-birth rate associated with repeat in vitro fertilization treatment cycles
© 2015 American Medical Association. All rights reserved. Importance The likelihood of achieving a live birth with repeat in vitro fertilization (IVF) is unclear, yet treatment is commonly limited to 3 or 4 embryo transfers. Objective To determine the live-birth rate per initiated ovarian stimulation IVF cycle and with repeated cycles. Design, Setting, and Participants Prospective study of 156 947 UKwomen who received 257 398 IVF ovarian stimulation cycles between 2003 and 2010 and were followed up until June 2012. Exposures In vitro fertilization, with a cycle defined as an episode of ovarian stimulation and all subsequent separate fresh and frozen embryo transfers. Main Outcomes and Measures Live-birth rate per IVF cycle and the cumulative live-birth rates across all cycles in all women and by age and treatment type. Optimal, prognosis-adjusted, and conservative cumulative live-birth rates were estimated, reflecting 0%, 30%, and 100%, respectively, of women who discontinued due to poor prognosis and having a live-birth rate of 0 had they continued. Results Among the 156 947 women, the median age at start of treatment was 35 years (interquartile range, 32-38; range, 18-55), and the median duration of infertility for all 257 398 cycles was 4 years (interquartile range, 2-6; range
Using Mendelian Randomisation to Prioritise Candidate Maternal Metabolic Traits Influencing Offspring Birthweight
Marked physiological changes in pregnancy are essential to support foetal growth; however, evidence on the role of specific maternal metabolic traits from human studies is limited. We integrated Mendelian randomisation (MR) and metabolomics data to probe the effect of 46 maternal metabolic traits on offspring birthweight (N = 210,267). We implemented univariable two-sample MR (UVMR) to identify candidate metabolic traits affecting offspring birthweight. We then applied two-sample multivariable MR (MVMR) to jointly estimate the potential direct causal effect for each candidate maternal metabolic trait. In the main analyses, UVMR indicated that higher maternal glucose was related to higher offspring birthweight (0.328 SD difference in mean birthweight per 1 SD difference in glucose (95% CI: 0.104, 0.414)), as were maternal glutamine (0.089 (95% CI: 0.033, 0.144)) and alanine (0.137 (95% CI: 0.036, 0.239)). In additional analyses, UVMR estimates were broadly consistent when selecting instruments from an independent data source, albeit imprecise for glutamine and alanine, and were attenuated for alanine when using other UVMR methods. MVMR results supported independent effects of these metabolites, with effect estimates consistent with those seen with the UVMR results. Among the remaining 43 metabolic traits, UVMR estimates indicated a null effect for most lipid-related traits and a high degree of uncertainty for other amino acids and ketone bodies. Our findings suggest that maternal gestational glucose and glutamine are causally related to offspring birthweight
Patients With Normal Tension Glaucoma Have Relative Sparing of the Relative Afferent Pupillary Defect Compared to Those With Open Angle Glaucoma and Elevated Intraocular Pressure
PURPOSE: We determined whether there is relative sparing of pupil function in glaucoma patients with normal pressures compared to those with high pressures. METHODS: A cross-sectional study was done of 68 patients with primary open angle glaucoma (POAG): 38 had normal IOPs on all-day phasing before treatment (never >21 mm Hg), with confirmed progression of glaucomatous optic neuropathy (NTG) and 30 had glaucomatous optic neuropathy associated with elevated intraocular pressures (>25 mm Hg; HP-POAG). The relative afferent pupillary defect (RAPD) was quantified with the RAPDx device, and mean deviation of visual field loss was obtained from reliable Humphrey visual fields. Outcomes measures evaluated were difference in slope between NTG and HP-POAG when plotting: (1) RAPD score against difference in mean deviation (MD) between eyes, and (2) RAPD score against difference in RNFL thickness between eyes. RESULTS: The slopes for magnitude of RAPD versus difference in MD were -0.06 (95% confidence interval [CI], -0.076, -0.044) for patients with NTG and -0.08 (95% CI, -0.109, -0.067) for those with HP-POAG. Fitting the interaction term showed a statistically significant difference between the slopes (0.023; 95% CI [0.0017, 0.0541]; P value = 0.037; HP-POAG reference group). Thus, for difference in MD, the slope for patients with NTG was flatter than the slope for those with HP-POAG. CONCLUSIONS: Glaucoma patients with NTG have a lesser RAPD for a given level of intereye difference of HVF MD, compared to patients with high IOPs. This suggests that damage to intrinsically photosensitive retinal ganglion cells (ipRGCs) differs between the normal and high-pressure forms of open-angle glaucoma (OAG), and supports the theory that mitochondrial optic neuropathies may have a role in the group of diagnoses currently termed normal tension glaucoma
- …