4,130 research outputs found
Theoretical Properties of Projection Based Multilayer Perceptrons with Functional Inputs
Many real world data are sampled functions. As shown by Functional Data
Analysis (FDA) methods, spectra, time series, images, gesture recognition data,
etc. can be processed more efficiently if their functional nature is taken into
account during the data analysis process. This is done by extending standard
data analysis methods so that they can apply to functional inputs. A general
way to achieve this goal is to compute projections of the functional data onto
a finite dimensional sub-space of the functional space. The coordinates of the
data on a basis of this sub-space provide standard vector representations of
the functions. The obtained vectors can be processed by any standard method. In
our previous work, this general approach has been used to define projection
based Multilayer Perceptrons (MLPs) with functional inputs. We study in this
paper important theoretical properties of the proposed model. We show in
particular that MLPs with functional inputs are universal approximators: they
can approximate to arbitrary accuracy any continuous mapping from a compact
sub-space of a functional space to R. Moreover, we provide a consistency result
that shows that any mapping from a functional space to R can be learned thanks
to examples by a projection based MLP: the generalization mean square error of
the MLP decreases to the smallest possible mean square error on the data when
the number of examples goes to infinity
Butt Joint Reinforcement in Parallel-Laminated Veneer (PLV) Lumber
Parallel-laminated veneer (PLV) is a high-strength structural material consisting of thin parallel-laminated wood veneers. The use of graphite-cloth reinforcement, placed on either side of a butt joint in 1 1/2- by 3 1/2- by 32-inch Douglas-fir PLV tensile members, was assessed. The finite-element method of analysis was used to predict the behavior in different unreinforced and reinforced butt-jointed PLV tensile members. Relationships between the reinforcing parametersâlength, modulus of elasticity, and thicknessâand the stresses in the wood and reinforcement components were developed by regression analysis techniques. The reinforcing mechanism reduced the peak stresses at the butt joint and hence increased the ultimate strength of the member. Design of PLV material whose strength is limited by shear stresses that develop at the butt joint is facilitated by use of the proposed relationships.Experimental testing confirmed the predictions of the finite-element analysis. Failure initiated at the unreinforced joint in the specimens. Average tensile strength increased and variability decreased in reinforced specimens. Application of a small amount of reinforcement at the butt joint has been shown to enhance PLV performance
Women, know your limits: Cultural sexism in academia
Despite the considerable advances of the feminist movement across Western societies, in Universities women are less likely to be promoted, or paid as much as their male colleagues, or even get jobs in the first place. One way in which we can start to reflect on why this might be the case is through hearing the experiences of women academics themselves. Using feminist methodology, this article attempts to unpack and explore just some examples of
âcultural sexismâ which characterise the working lives of many women in British academia.This article uses qualitative methods to describe and make sense of just some of those experiences. In so doing, the argument is also made that the activity of academia is profoundly gendered and this explicit acknowledgement may contribute to our
understanding of the under-representation of women in senior positions
Growth, profits and technological choice: The case of the Lancashire cotton textile industry
Using Lancashire textile industry company case studies and financial records, mainly from the period just before the First World War, the processes of growth and decline are re-examined. These are considered by reference to the nature of Lancashire entrepreneurship and the impact on technological choice. Capital accumulation, associated wealth distributions and the character of Lancashire business organisation were sybiotically linked to the success of the industry before 1914. However, the legacy of that accumulation in later decades, chronic overcapacity, formed a barrier to reconstruction and enhanced the preciptious decline of a once great industry
Variation in the achievement of HbA1c, blood pressure and LDL cholesterol targets in type 2 diabetes in general practice and characteristics associated with risk factor control.
Aims
To identify population, general practitioner, and practice characteristics associated with the achievement of HbA1c, blood pressure and LDL cholesterol targets, and to describe variation in the achievement of risk factor control.
Methods
We conducted a crossâsectional survey of 9342 people with type 2 diabetes, 281 general practitioners and 77 general practices in Norway. Missing values (7.4%) were imputed using multiple imputation by chained equations. We used threeâlevel logistic regression with the achievement of HbA1c, blood pressure and LDL cholesterol targets as dependent variables, and factors related to population, general practitioners, and practices as independent variables.
Results
Treatment targets were achieved for HbA1c in 64%, blood pressure in 50%, and LDL cholesterol in 52% of people with type 2 diabetes, and 17% met all three targets. There was substantial heterogeneity in target achievement among general practitioners and among practices; the estimated proportion of a GPs diabetes population at target was 55â73% (10â90 percentiles) for HbA1c, 36â63% for blood pressure, and 47â57% for LDL cholesterol targets. The models explained 11%, 5% and 14%, respectively, of the total variation in the achievement of HbA1c, blood pressure and LDL cholesterol targets. Use among general practitioners of a structured diabetes form was associated with 23% higher odds of achieving the HbA1c target (odds ratio 1.23, 95% confidence interval (CI) 1.02â1.47) and 17% higher odds of achieving the LDL cholesterol target (odds ratio 1.17, 95% CI 1.01â1.35).
Conclusions
Clinical diabetes management is difficult, and few people meet all three risk factor control targets. The proportion of people reaching target varied among general practitioners and practices. Several population, general practitioner and practice characteristics only explained a small part of the total variation. The use of a structured diabetes form is recommended.publishedVersio
Parent-Dependent Stressors and the Onset of Anxiety Disorders in Children: Links with Parental Psychopathology
Exposure to stressors is associated with an increased risk for child anxiety. Investigating the family origins of stressors may provide promising avenues for identifying and intervening with children at risk for the onset of anxiety disorders and their families. The aim of this study was to compare the frequency of parent-dependent negative life events and chronic adversities experienced by children with an anxiety disorder (n = 34) in the 12 months prior to the onset of the childâs most recent episode, compared to healthy controls (n = 34). Life events and chronic adversities were assessed using maternal report during an investigator-based interview, which provided independent panel ratings of the extent that reported experiences were related to parent behaviour. There were no group differences in the number of parent-dependent negative life events for anxious children compared to controls. However, significantly more parent-dependent chronic adversities were present for anxious children compared to controls. Findings suggest that parents contribute to an increased frequency of chronic adversities but not negative life events prior to their childâs most recent onset of anxiety. Furthermore, increased child exposure to parent-dependent chronic adversities was related to parental history of mental disorder
- âŠ