Volumetric pattern analysis of airborne antennas

By blending together the roll and elevation plane high frequency solutions, a very efficient technique was developed for the volumetric pattern analysis of antennas mounted on the fuselage of a generalized aircraft. The fuselage is simulated by an infinitely long, perfectly conducting, elliptic cylinder in cross-section and a composite elliptic cylinder in profile. The wings, nose section, stabilizers, and landing gear doors may be modeled by finite flat or bent plates. Good agreement with accurate scale model measurements was obtained for a variety of airborne antenna problems

Hedging and Financial Fragilities in Fixed Exchange Rate Regimes.

Currency crises that coincide with banking crises tend to share four elements. First, governments provide guarantees to domestic and foreign bank creditors. Second, banks do not hedge their exchange rate risk. Third, there is a lending boom before the crises. Finally, when the currency/banking collapse occurs interest rates rise and there is a persistent decline in output. This paper proposes an explanation for these regularities.BANKS ; EXCHANGE RATE ; FINANCIAL MARKET

Multiple Sample Cryostat for the Determination of Superconductor Properties

Cryostats which are currently used to characterize the properties of superconductors between 4 K and 100 K are primarily single sample devices. The purpose of this paper is to present an instrument design which can hold up to five (5) one cm. diameter samples at a stable temperature (+ /-0.1K) within the above range specified while measurements of the sample properties are made

An assessment of the impacts of child oral health in Indonesia and associations with self-esteem, school performance and perceived employability

Background Previous surveys have indicated that a majority of Indonesian children have poor oral health. However, little detailed information is available on underlying causation and none that examine impacts of oral health on child self-esteem, school performance and perceived employability. The aim of this study was to determine levels of child oral health in primary school children in Indonesia, the prevalence of key causal factors; and, to determine relationships between oral health, self-esteem and school academic performance. Methods Cross-sectional epidemiological study in a sample (n = 984) of children aged 6–7 and 10–11 years old attending three public schools in Indonesia. A dental visual impact study was conducted, in which teachers reported their perceptions of the impact of child oral health on school academic performance. Oral health behaviors, self-esteem, and school performance were assessed. The children were clinically examined to measure dental caries and oral cleanliness. Results Teachers believe that children with visually poor oral health and impaired smiles are more likely to perform poorly at school, be socially excluded and have lower job prospects than their peers with visually good oral health and healthy smiles. The percentages of children with decayed teeth were 94 and 90% in the 6-7- and 10–11-year age groups, respectively. Families reported high levels of child consumption of sugar-containing foods and drinks; many had irregular use of fluoride toothpaste. Children with substantial plaque on their teeth achieved significantly lower levels of school performance than their peers with clean teeth. Significant associations were found between school performance and self-esteem for these children. Conclusions The study findings highlight the need for preventive care programs to improve the oral health of children in Indonesia and prospective determination of associations between child oral health; self-esteem and school academic performance

A Model for the Analysis of Caries Occurrence in Primary Molar Tooth Surfaces

Recently methods of caries quantification in the primary dentition have moved away from summary ‘whole mouth’ measures at the individual level to methods based on generalised linear modelling (GLM) approaches or survival analysis approaches. However, GLM approaches based on logistic transformation fail to take into account the time-dependent process of tooth/surface survival to caries. There may also be practical difficulties associated with casting parametric survival-based approaches in a complex multilevel hierarchy and the selection of an optimal survival distribution, while non-parametric survival methods are not generally suitable for the assessment of supplementary information recorded on study participants. In the current investigation, a hybrid semi-parametric approach comprising elements of survival-based and GLM methodologies suitable for modelling of caries occurrence within fixed time periods is assessed, using an illustrative multilevel data set of caries occurrence in primary molars from a cohort study, with clustering of data assumed to occur at surface and tooth levels. Inferences of parameter significance were found to be consistent with previous parametric survival-based analyses of the same data set, with gender, socio-economic status, fluoridation status, tooth location, surface type and fluoridation status-surface type interaction significantly associated with caries occurrence. The appropriateness of the hierarchical structure facilitated by the hybrid approach was also confirmed. Hence the hybrid approach is proposed as a more appropriate alternative to primary caries modelling than non-parametric survival methods or other GLM-based models, and as a practical alternative to more rigorous survival-based methods unlikely to be fully accessible to most researchers

An evaluation of a storybook targeting parental attitudes, intention and self-efficacy to change their child’s oral health behaviour

Objective: Methods for reducing dental disease have traditionally focused on health education rather than targeting psychosocial determinants of the core behaviours through behaviour change strategies. This study tested a novel intervention in the form of a children’s story (Kitten’s First Tooth) embedded with behaviour change techniques (Abraham and Michie, 2008) with the aim of investigating how effective the intervention was at improving parents’ efficacy and intention to enact oral health behaviours for their child.Methods: A controlled before and after study conducted in a deprived area of England (n=149; child mean age 4 years) with an intervention and control group. Changes in task specific parental self-efficacy (PSE) and intention were measured using the Oral Health Behaviours Questionnaire (OHBQ; Adair et al., 2004) at baseline and 3 months following intervention. Results: Of the 149 participants, 129 returned both baseline and evaluation questionnaires (retention 86.6%), 125 of these pairs of questionnaires were used in the analysis (83.4%). The OHBQ was analysed using a general linear model (ANCOVA). A significant difference was found in favour of the intervention group for PSE related to child tooth brushing behaviours (F(1,1)=12.04, p=0.001), however no change was observed for PSE related to control of dietary sugars. Conclusions: A theorized children’s story can be effective as an oral health promotion intervention by supporting parents to improve their child’s oral health-related behaviour. Change was observed for child tooth brushing but not sugar control. This may reflect story contents or may be indicative of difficulties of changing dietary behaviour

On uniformization of Burnside's curve y2=x5−xy^2=x^5-x

Main objects of uniformization of the curve $y^2=x^5-x$ are studied: its Burnside's parametrization, corresponding Schwarz's equation, and accessory parameters. As a result we obtain the first examples of solvable Fuchsian equations on torus and exhibit number-theoretic integer $q$-series for uniformizing functions, relevant modular forms, and analytic series for holomorphic Abelian integrals. A conjecture of Whittaker for hyperelliptic curves and its hypergeometric reducibility are discussed. We also consider the conversion between Burnside's and Whittaker's uniformizations.Comment: Final version. LaTeX, 23 pages, 1 figure. The handbook for elliptic functions has been moved to arXiv:0808.348

Large Deviation Approach to the Randomly Forced Navier-Stokes Equation

The random forced Navier-Stokes equation can be obtained as a variational problem of a proper action. By virtue of incompressibility, the integration over transverse components of the fields allows to cast the action in the form of a large deviation functional. Since the hydrodynamic operator is nonlinear, the functional integral yielding the statistics of fluctuations can be practically computed by linearizing around a physical solution of the hydrodynamic equation. We show that this procedure yields the dimensional scaling predicted by K41 theory at the lowest perturbative order, where the perturbation parameter is the inverse Reynolds number. Moreover, an explicit expression of the prefactor of the scaling law is obtained.Comment: 24 page

The BBaRTS Healthy Teeth Behaviour Change Programme for preventing dental caries in primary school children: study protocol for a cluster randomised controlled trial

Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were madeThis trial is supported by an unrestricted grant from GlaxoSmithKlin