876 research outputs found
A cooking pot lit by fire
Recent research into the records of eclipses in the Chronicle of the English monk, Gervase of Canterbury, has indicated that an entry for the year 1187 C.E. may contain a description of solar prominences being visible during the total eclipse of that year. As such it is not only the earliest report of the phenomenon from England, but also reveals that a British Library manuscript contains the earliest surviving contemporary record of such an observation
A study on the fourth q-Painlev\'e equation
A q-difference analogue of the fourth Painlev\'e equation is proposed. Its
symmetry structure and some particular solutions are investigated.Comment: 18 page
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Nested, fixed-depth fluidic sampler and analysis system deployment strategy and plan
Under the Hanford Site Tank Waste Remediation System (TWRS) privatization strategy, the US Department of Energy (DOE) requires the Project Hanford Management Contract (PHMC) Team to supply tank wastes to the Privatization Contractor for separation, treatment and immobilization (verification). Three low-activity waste (LAW) envelopes represent the range of the liquid wastes in the large underground waste-storage tank at the Hanford Site. The PHMC Team also is expected to supply high-level waste (HLW) to the Privatization Contractor. The LAW envelope is an aqueous slurry of insoluble suspended solids (sludge). The Phase 1 demonstration period will extend over 10-plus years. Wastes processed during this period will result in 6% to 13% of the total Hanford Site tank waste being treated. The purpose of this document is to provide a strategy and top-level implementation plan for the demonstration and deployment of an alternative sampling technology as an improvement to the current grab sampling approach to support the TWRS privatization. Included in this work is the addition of the capability for some at-tank analysis to enhance the use of this technology for meeting the PHMC Team`s needs. The first application of this technology is to LAW feed staging, then to HLW feed staging, and finally to cross-site transfer to support feed staging from 200 West Area tanks. The TWRS retrieval and disposal mission readiness-to-proceed activities in the first quarter of Fiscal Year (FY) 1998 identified the primary uncertainties and risks that must be managed to successfully carry out the support of the TWRS Phase 1 activities. Four of the critical risks could be mitigated, at least partially, by the use of an improved alternative to grab sampling. In addition, eight of the risks with the Waste Feed Delivery Project were associated with the sampling activities. Over 25 logic elements, Technical Basis Reviews (TBR), were reviewed and found to be relevant to risk mitigation using an improved alternative to grab sampling. This document describes these risks and uses a methodology for risk analysis to determine a preliminary estimate of return on investment for pursuing an alternative sampling technology. The basis for the estimate will be firmed up as fiscal year multi-year work planning is conducted and the associated TBRs and cost estimating input sheets are updated. In this calculation the benefits were conservatively estimated to accrue only during the first five years of operation; with this assumption, a return of about double the original investment for development and deployment was projected
Semi-field assessment of the BG-Malaria trap for monitoring the African malaria vector, Anopheles arabiensis
Odour-baited technologies are increasingly considered for effective monitoring of mosquito populations and for the evaluation of vector control interventions. The BG-Malaria trap (BGM), which is an upside-down variant of the widely used BG-Sentinel trap (BGS), has been demonstrated to be effective to sample the Brazilian malaria vector, Anopheles darlingi. We evaluated the BGM as an improved method for sampling the African malaria vectors, Anopheles arabiensis. Experiments were conducted inside a large semi-field cage to compare trapping efficiencies of BGM and BGS traps, both baited with the synthetic attractant, Ifakara blend, supplemented with CO2. We then compared BGMs baited with either of four synthetic mosquito lures, Ifakara blend, Mbita blend, BG-lure or CO2, and an unbaited BGM. Lastly, we compared BGMs baited with the Ifakara blend dispensed via either nylon strips, BG cartridges (attractant-infused microcapsules encased in cylindrical plastic cartridge) or BG sachets (attractant-infused microcapsules encased in plastic sachets). All tests were conducted between 6P.M. and 7A.M., with 200–600 laboratory-reared An. arabiensis released nightly in the test chamber. The median number of An. arabiensis caught by the BGM per night was 83, IQR:(73.5–97.75), demonstrating clear superiority over BGS (median catch = 32.5 (25.25–37.5)). Compared to unbaited controls, BGMs baited with Mbita blend caught most mosquitoes (45 (29.5–70.25)), followed by BGMs baited with CO2 (42.5 (27.5–64)), Ifakara blend (31 (9.25–41.25)) and BG lure (16 (4–22)). BGM caught 51 (29.5–72.25) mosquitoes/night, when the attractants were dispensed using BG-Cartridges, compared to BG-Sachet (29.5 (24.75–40.5)), and nylon strips (27 (19.25–38.25)), in all cases being significantly superior to unbaited controls (p < 000.1). The findings demonstrate potential of the BGM as a sampling tool for African malaria vectors over the standard BGS trap. Its efficacy can be optimized by selecting appropriate odour baits and odour-dispensing systems
Methodology for the comparative assessment of the Satellite Power System (SPS) and alternative technologies
The energy systems concerned are the satellite power system, several coal technologies, geothermal energy, fission, fusion, terrestrial solar systems, and ocean thermal energy conversion. Guidelines are suggested for the characterization of these systems, side-by-side analysis, alternative futures analysis, and integration and aggregation of data. A description of the methods for assessing the technical, economic, environmental, societal, and institutional issues surrounding the development of the selected energy technologies is presented
A double bounded key identity for Goellnitz's (big) partition theorem
Given integers i,j,k,L,M, we establish a new double bounded q-series identity
from which the three parameter (i,j,k) key identity of Alladi-Andrews-Gordon
for Goellnitz's (big) theorem follows if L, M tend to infinity. When L = M, the
identity yields a strong refinement of Goellnitz's theorem with a bound on the
parts given by L. This is the first time a bounded version of Goellnitz's (big)
theorem has been proved. This leads to new bounded versions of Jacobi's triple
product identity for theta functions and other fundamental identities.Comment: 17 pages, to appear in Proceedings of Gainesville 1999 Conference on
Symbolic Computation
Hypergeometric solutions to the q-Painlev\'e equation of type
We consider the q-Painlev\'e equation of type (a version of
q-Painlev\'e V equation) and construct a family of solutions expressible in
terms of certain basic hypergeometric series. We also present the determinant
formula for the solutions.Comment: 16 pages, IOP styl
Implementation and scaling of the fully coupled Terrestrial Systems Modeling Platform (TerrSysMP) in a massively parallel supercomputing environment – a case study on JUQUEEN (IBM Blue Gene/Q)
Continental-scale hyper-resolution simulations constitute a grand challenge in characterizing non-linear feedbacks of states and fluxes of the coupled water, energy, and biogeochemical cycles of terrestrial systems. Tackling this challenge requires advanced coupling and supercomputing technologies for earth system models that are discussed in this study, utilizing the example of the implementation of the newly developed Terrestrial Systems Modeling Platform (TerrSysMP) on JUQUEEN (IBM Blue Gene/Q) of the Jülich Supercomputing Centre, Germany. The applied coupling strategies rely on the Multiple Program Multiple Data (MPMD) paradigm and require memory and load balancing considerations in the exchange of the coupling fields between different component models and allocation of computational resources, respectively. These considerations can be reached with advanced profiling and tracing tools leading to the efficient use of massively parallel computing environments, which is then mainly determined by the parallel performance of individual component models. However, the problem of model I/O and initialization in the peta-scale range requires major attention, because this constitutes a true big data challenge in the perspective of future exa-scale capabilities, which is unsolved
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