Magnetic tomography for lead acid batteries

© 2017 The AuthorsThis paper explores the inverse problem approach for finding the current distribution within an electrochemical cell from magnetic field measurements. Current distribution is shown to be a useful measurement for diagnosis of cells and development of cell design. Existing current distribution measurement methods are discussed to provide context and motivation for the work. Magnetic field measurements can be obtained non-invasively and contain information about the current distribution, which is extracted using an appropriate solver. Experimental results are presented which test the effectiveness of a particular inverse problem solver, using both simulated and real magnetic field measurements. The solver presented is based upon one found in literature, but with novel problem-specific modifications. Errors in conductance values in the forward model definition are simulated in order to quantify their effect on solution quality. A modification to the solver is proposed to improve robustness against these model errors. This results in improved solution quality when using real measured data from a resistor-wire model of a cell, and simulated data from a model which more accurately represents the conductance of the cell plate grid and active mass

Actors that Unify Threads and Events

There is an impedance mismatch between message-passing concurrency and virtual machines, such as the JVM. VMs usually map their threads to heavyweight OS processes. Without a lightweight process abstraction, users are often forced to write parts of concurrent applications in an event-driven style which obscures control flow, and increases the burden on the programmer. In this paper we show how thread-based and event-based programming can be unified under a single actor abstraction. Using advanced abstraction mechanisms of the Scala programming language, we implemented our approach on unmodified JVMs. Our programming model integrates well with the threading model of the underlying VM

The relationship between fetal growth and retinal nerve fiber layer thickness in a cohort of young adults

Purpose: To explore relationships between patterns of fetal anthropometric growth, as reflective of fetal wellbeing, and global retinal nerve fiber layer (RNFL) thickness measured in young adulthood. Methods: Participants (n = 481) from within a Western Australian pregnancy cohort study underwent five serial ultrasound scans during gestation, with fetal biometry measured at each scan. Optic disc parameters were measured via spectral-domain optical coherence tomography imaging at a 20-year follow-up eye examination. Generalized estimating equations were used to evaluate differences in global RNFL thickness between groups of participants who had undergone similar growth trajectories based on fetal head circumference (FHC), abdominal circumference (FAC), femur length (FFL), and estimated fetal weight (EFW). Results: Participants with consistently large FHCs throughout gestation had significantly thicker global RNFLs than those with any other pattern of FHC growth (P = 0.023), even after adjustment for potential confounders (P = 0.037). Based on model fit statistics, FHC growth trajectory was a better predictor of global RNFL thickness than birth weight or head circumference at birth. RNFL thickness did not vary significantly between groups of participants with different growth trajectories based on FAC, FFL, or EFW. Conclusions: FHC growth is associated with RNFL thickness in young adulthood and, moreover, is a better predictor than either birth weight or head circumference at birth. Translational Relevance: This research demonstrates an association between intrauterine growth and long-term optic nerve health, providing a basis for further exploring the extent of the influence of fetal wellbeing on clinical conditions linked to RNFL thinning

High frequency modelling of electric machines using finite element analysis derived data

The use of wide band gap semiconductor switching devices in electric machine drives leads to a significant increase in power density and efficiency compared to conventional silicon-based solutions. However, this technology also presents challenges for the insulation design of electric machines since partial discharges (PDs) may occur due to high peak voltage stress as a result of fast and high frequency switching. To evaluate the risk of PD, it is necessary to understand the voltage distribution within the windings and associated insulation of an electric machine during converter operation. To this end a suitable high frequency model of the machine windings capable of predicting the internal voltage distribution is required. This paper proposes a method of constructing such a model based on finite element analysis (FEA) derived data. The FEA data used to parameterise the model in this work incorporates frequency dependant properties and homogenisation techniques to produce data which captures the high frequency behaviour of the machine. The developed model is compared with measurements in both frequency and time domains, demonstrating the utility and accuracy of the model

A united front against marine invaders: Developing a cost‐effective marine biosecurity surveillance partnership between government and industry

Successful detection of introduced marine pests (IMP) relies upon effective surveillance. However, the expedience of responding following IMP detection is often dependent upon the relationship between regulators and stakeholders. Effective detection of IMP in areas such as commercial ports requires a collaborative approach, as port environments can be highly complex both above and below the water. This complexity can encompass physical, logistical, safety and legislative issues. With this in mind, the aquatic pest biosecurity section within the Department of Primary Industries and Regional Development (DPIRD) developed the State‐Wide Array Surveillance Program (SWASP) in collaboration with Western Australian Port Authorities and port industry stakeholders. The SWASP is primarily based on passive settlement arrays for IMP detection. Arrays are deployed at strategic locations within Ports. Marine growth samples collected from the arrays are processed using Next‐Generation Sequencing (NGS) to identify the presence of IMP within a specific geographical location. Over 8 years, participation in SWASP has grown from 3 to 11 ports, spanning over 11,000 km, from the tropical north to temperate south of Western Australia. The programme has proven to be highly effective as a means of fostering stakeholder involvement and, importantly for IMP surveillance. The growth and success of SWASP has continued primarily because of the commitment and farsightedness of the ports involved. The regular presence of the biosecurity regulator as a partner in SWASP has provided a consistent face for biosecurity and fostered good stakeholder relationships, ensuring there is a reliable and effective ongoing marine surveillance programme for the state. Synthesis and applications. Through a united and collaborative approach to marine biosecurity surveillance, port authorities, industry and biosecurity regulators have developed the State‐Wide Array Surveillance Program (SWASP) and closed a major gap in biosecurity surveillance. The SWASP collaboration uses passive settlement arrays and molecular analyses to provide regular marine pest surveillance from the tropics to temperate regions of Western Australia. The continued commitment has embedded valuable relationships between stakeholder and regulator ensuring ongoing surveillance in marine biosecurity for the state. The Western Australian SWASP example has inspired other jurisdictions around Australia to develop similar collaborative approaches which will have far‐reaching marine biosecurity benefits

De Finetti theorem on the CAR algebra

The symmetric states on a quasi local C*-algebra on the infinite set of indices J are those invariant under the action of the group of the permutations moving only a finite, but arbitrary, number of elements of J. The celebrated De Finetti Theorem describes the structure of the symmetric states (i.e. exchangeable probability measures) in classical probability. In the present paper we extend De Finetti Theorem to the case of the CAR algebra, that is for physical systems describing Fermions. Namely, after showing that a symmetric state is automatically even under the natural action of the parity automorphism, we prove that the compact convex set of such states is a Choquet simplex, whose extremal (i.e. ergodic w.r.t. the action of the group of permutations previously described) are precisely the product states in the sense of Araki-Moriya. In order to do that, we also prove some ergodic properties naturally enjoyed by the symmetric states which have a self--containing interest.Comment: 23 pages, juornal reference: Communications in Mathematical Physics, to appea

A multiplex microsatellite set for non-invasive genotyping and sexing of the osprey (Pandion haliaetus)

During the 1950s and 1970s the osprey (Pandion haliaetus) experienced a dramatic population crash and remains of conservation concern in several parts of the world. We isolated 37 microsatellite loci and assessed these in ospreys sampled in the UK and Norway (using mouth swabs/feathers). From 26 loci variable in four ospreys, we selected 13, combined these into two multiplex-PCR sets and included a sex-typing marker. Additional markers confirmed sexes. In 17 ospreys, feather-sampled in central Norway, we found 3–10 alleles per locus. The 13 loci are autosomal (heterozygotes were present in both sexes) and observed heterozygosities ranged from 0.24 to 0.94. The combined probability of identity for the 13 loci was 8.0 × 10−12. These microsatellite loci will be useful for genetic monitoring, parentage analysis and population genetic studies of the osprey

Pediatric cataract, myopic astigmatism, familial exudative vitreoretinopathy and primary open-angle glaucoma co-segregating in a family

Purpose: To describe an Australian pedigree of European descent with a variable autosomal dominant phenotype of: pediatric cortical cataract (CC), asymmetric myopia with astigmatism, familial exudative vitreoretinopathy (FEVR), and primary open-angle glaucoma (POAG). Methods: Probands with CC, FEVR, and POAG were enrolled in three independent genetic eye studies in Tasmania. Genealogy confirmed these individuals were closely related and subsequent examination revealed 11 other family members with some or all of the associated disorders. Results: Twelve individuals had CC thought to be of childhood onset, with one child demonstrating progressive lenticular opacification. One individual had severe retinal detachment while five others had dragged retinal vessels. Seven individuals had POAG. Seven individuals had myopia in at least one eye ≤-3 Diopters. DNA testing excluded mutations in myocilin, trabecular meshwork inducible glucocorticoid response (MYOC) and tetraspanin 12 (TSPAN12). Haplotype analysis excluded frizzled family receptor 4 (FZD4) and low density lipoprotein receptor-related protein 5 (LRP5), but only partly excluded EVR3. Multipoint linkage analysis revealed multiple chromosomal single-nucleotide polymorphisms (SNPs) of interest, but no statistically significant focal localization. Conclusions: This unusual clustering of ophthalmic diseases suggests a possible single genetic cause for an apparently new cataract syndrome. This family’s clinical ocular features may reflect the interplay between retinal disease with lenticular changes and axial length in the development of myopia and glaucoma

Rare variants in optic disc area gene CARD10 enriched in primary open-angle glaucoma

Background: Genome-wide association studies (GWAS) have identified association of common alleles with primary open-angle glaucoma (POAG) and its quantitative endophenotypes near numerous genes. This study aims to determine whether rare pathogenic variants in these disease-associated genes contribute to POAG. Methods: Participants fulfilled strict inclusion criteria of advanced POAG at a young age of diagnosis. Myocilin mutation carriers were excluded using direct sequencing. Whole exome sequencing was performed on 187 glaucoma cases and 103 local screened nonglaucoma controls then joint-called with exomes of 993 previously sequenced Australian controls. GWAS-associated genes were assessed for enrichment of rare predicted pathogenic variants in POAG. Significantly enriched genes were compared against Exome Aggregation Consortium (ExAC) public control. Results: Eighty-six GWAS disease or trait-associated glaucoma genes were captured and sequenced. CARD10 showed enrichment after Bonferroni correction for rare variants in glaucoma cases (OR = 13.2, P = 6.94 × 10−5) with mutations identified in 4.28% of our POAG cohort compared to 0.27% in controls. CARD10 was significantly associated with optic disc parameters in previous GWAS. The whole GWAS gene set showed no enrichment in POAG overall (OR = 1.12, P = 0.51). Conclusion: We report here an enrichment of rare predicted pathogenic coding variants within a GWAS-associated locus in POAG (CARD10). These findings indicate that both common and rare pathogenic coding variants in CARD10 may contribute to POAG pathogenesis.Tiger Zhou, Emmanuelle Souzeau, Shiwani Sharma, Owen M. Siggs, Ivan Goldberg, Paul R. Healey, Stuart Graham, Alex W. Hewitt, David A. Mackey, Robert J. Casson, John Landers, Richard Mills, Jonathan Ellis, Paul Leo, Matthew A. Brown, Stuart MacGregor, Kathryn P. Burdon and Jamie E. Crai

Hole concentration and phonon renormalization in Ca-doped YBa_2Cu_3O_y (6.76 < y < 7.00)

In order to access the overdoped regime of the YBa_2Cu_3O_y phase diagram, 2% Ca is substituted for Y in YBa_2Cu_3O_y (y = 7.00,6.93,6.88,6.76). Raman scattering studies have been carried out on these four single crystals. Measurements of the superconductivity-induced renormalization in frequency (Delta \omega) and linewidth (\Delta 2\gamma) of the 340 cm^{-1} B_{1g} phonon demonstrate that the magnitude of the renormalization is directly related to the hole concentration (p), and not simply the oxygen content. The changes in \Delta \omega with p imply that the superconducting gap (\Delta_{max}) decreases monotonically with increasing hole concentration in the overdoped regime, and \Delta \omega falls to zero in the underdoped regime. The linewidth renormalization \Delta 2\gamma is negative in the underdoped regime, crossing over at optimal doping to a positive value in the overdoped state.Comment: 18 pages; 5 figures; submitted to Phys. Rev. B Oct. 24, 2002 (BX8292