Ion-tracer anemometer

Gas velocity measuring instrument measures transport time of ion-trace traveling fixed distance between ionization probe and detector probe. Electric field superimposes drift velocity onto flow velocity so travel times can be reduced to minimize ion diffusion effects

Digital computer simulation of inductor-energy-storage dc-to-dc converters with closed-loop regulators

The simulation of converter-controller combinations by means of a flexible digital computer program which produces output to a graphic display is discussed. The procedure is an alternative to mathematical analysis of converter systems. The types of computer programming involved in the simulation are described. Schematic diagrams, state equations, and output equations are displayed for four basic forms of inductor-energy-storage dc to dc converters. Mathematical models are developed to show the relationship of the parameters

Performance characteristics of eight estradiol immunoassays

Journal ArticleMeasurement of estradiol is useful in assisted reproduction, evaluation of infertility, menopause, and male feminization. The analytic performance of 8 estradiol immunoassays was evaluated. The imprecision and accuracy of the Access, ADVIA Centaur, ARCHITECT i2000, AutoDELFIA, Elecsys 2010, IMMULITE 2000, and Vitros ECi estradiol assays (see text for proprietary information) were evaluated by using an isotope dilution-gas chromatography-mass spectrometry (ID-GC-MS) reference method. The coefficient of variation (CV) ranged from 6.9% on the Elecsys 2010 to 42.6% on the ADVIA Centaur at an estradiol concentration of 18 pg/mL (66 pmol/L), with the ARCHITECT i2000 assay in development and the Vitros ECi having a CV below 10% at this estradiol concentration. Agreement between the automated assays and ID-GC-MS was variable, with slopes ranging from 0.87 to 1.20. The Access, ARCHITECT i2000 in development, and the IMMULITE 2000 were the most accurate, with slopes of 0.99, 0.98, and 1.03, respectively. These findings indicate that the ARCHITECT i2000 estradiol assay in development had the best precision and accuracy of the assays evaluated for measurement of serum estradiol concentrations

Environmental Monitoring on Research Centres and Large Farms Using Spatial Data Management Tools.

End of Project ReportThe objective of project 4480 was to build an environmental management system by using a visual or map based approach to develop new ways to manage environmental data on a large farm or an estate of several farms. Geographic information system (GIS) techniques are extremely powerful, but they tend to be complex, and often require a high degree of skill and training in order to use them. Using systems analysis, the fundamental environmental management data were identified and a simplified spatial approach was developed to manage these environmental data. Johnstown Castle Research Centre consists of three farms, ornamental grounds, forests, lakes and streams. A set of database tables was generated to hold farm environmental data on these farms. These included: annual management summary data giving the average number of different types of animals, the amount of organic manure and N, P and K nutrients produced by them, fertiliser purchases, organic and chemical nutrient usage on the farm, achievement of nutrient management planning targets, etc. monthly livestock information recording the numbers of livestock of different types for the three farms, together with management comments on the changes and transfer that take place over the month, detailed land use and nutrient use information for each field or plot on the estate, recent soil analyses information for the experimental plots, analysis results of recent water samples which are taken regularly at sampling points throughout the estate. The topographical, soil and site features were digitised, in order to collect information on the overall and individual farm boundaries. This included roads, hedges and ditches, streams, rivers and lakes, the buildings and most particularly, the boundaries of all field and experimental plots. When the digitisation was complete, a set of bespoke programs was built, using the GIS system, ArcView. To make the system "user friendly", the menu system was customised by removing complex features; retaining only those buttons and menu options that served a purpose useful to the application. The programs were unified into a PC system called Johnstown Castle Environmental Monitoring System or JCEMS. For the future, it is envisaged that the maps and spatial techniques will be embodied into an Access database system and developed for use by other research stations and farms.European Union Structural Funding (EAGGF

A digital computer simulation and study of a direct-energy-transfer power-conditioning system

A digital computer simulation technique, which can be used to study such composite power-conditioning systems, was applied to a spacecraft direct-energy-transfer power-processing system. The results obtained duplicate actual system performance with considerable accuracy. The validity of the approach and its usefulness in studying various aspects of system performance such as steady-state characteristics and transient responses to severely varying operating conditions are demonstrated experimentally

Hole Doping Effects on Spin-gapped Na2Cu2TeO6 via Topochemical Na Deficiency

We report the magnetic susceptibility and NMR studies of a spin-gapped layered compound Na2Cu2TeO6 (the spin gap $\Delta\sim$ 250 K), the hole doping effect on the Cu2TeO6 plane via a topochemical Na deficiency by soft chemical treatment, and the static spin vacancy effect by nonmagnetic impurity Zn substitution for Cu. A finite Knight shift at the $^{125}$Te site was observed for pure Na2Cu2TeO6. The negative hyperfine coupling constant $^{125}A_{tr}$ is an evidence for the existence of a superexchange pathway of the Cu-O-Te-O-Cu bond. It turned out that both the Na deficiency and Zn impurities induce a Curie-type magnetism in the uniform spin susceptibility in an external magnetic field of 1 T, but only the Zn impurities enhance the low-temperature $^{23}$Na nuclear spin-lattice relaxation rate whereas the Na deficiency suppresses it. A spin glass behavior was observed for the Na-deficient samples but not for the Zn-substituted samples. The dynamics of the unpaired moments of the doped holes are different from that of the spin vacancy in the spin-gapped Cu2TeO6 planes.Comment: 4 pages, 7 figures, to be published in J. Phys. Soc. Jpn. Vol. 75, No. 8 (2006

Predicting animal behaviour using deep learning: GPS data alone accurately predict diving in seabirds

1.:To prevent further global declines in biodiversity, identifying and understanding key habitats is crucial for successful conservation strategies. For example, globally, seabird populations are under threat and animal movement data can identify key at‐sea areas and provide valuable information on the state of marine ecosystems. To date, in order to locate these areas, studies have used global positioning system (GPS) to record position and are sometimes combined with time–depth recorder (TDR) devices to identify diving activity associated with foraging, a crucial aspect of at‐sea behaviour. However, the use of additional devices such as TDRs can be expensive, logistically difficult and may adversely affect the animal. Alternatively, behaviours may be resolved from measurements derived from the movement data alone. However, this behavioural analysis frequently lacks validation data for locations predicted as foraging (or other behaviours). 2.: Here, we address these issues using a combined GPS and TDR dataset from 108 individuals by training deep learning models to predict diving in European shags, common guillemots and razorbills. We validate our predictions using withheld data, producing quantitative assessment of predictive accuracy. The variables used to train these models are those recorded solely by the GPS device: variation in longitude and latitude, altitude and coverage ratio (proportion of possible fixes acquired within a set window of time). 3.: Different combinations of these variables were used to explore the qualities of different models, with the optimum models for all species predicting non‐diving and diving behaviour correctly over 94% and 80% of the time, respectively. We also demonstrate the superior predictive ability of these supervised deep learning models over other commonly used behavioural prediction methods such as hidden Markov models. 4.: Mapping these predictions provides useful insights into the foraging activity of a range of seabird species, highlighting important at sea locations. These models have the potential to be used to analyse historic GPS datasets and further our understanding of how environmental changes have affected these seabirds over time

Limiting behaviour of Fréchet means in the space of phylogenetic trees

As demonstrated in our previous work on T4, the space of phylogenetic trees with four leaves, the topological structure of the space plays an important role in the non-classical limiting behaviour of the sample Fréchet means in T4. Nevertheless, the techniques used in that paper cannot be adapted to analyse Fréchet means in the space Tm of phylogenetic trees with m(⩾5)m(⩾5) leaves. To investigate the latter, this paper first studies the log map of Tm. Then, in terms of a modified version of this map, we characterise Fréchet means in Tm that lie in top-dimensional or co-dimension one strata. We derive the limiting distributions for the corresponding sample Fréchet means, generalising our previous results. In particular, the results show that, although they are related to the Gaussian distribution, the forms taken by the limiting distributions depend on the co-dimensions of the strata in which the Fréchet means lie