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Evolutionism and Skepticism in the Thought of Robert Browning
This thesis has two primary objectives. The first is the presentation and the evaluation of various critical dicta regarding Browning's prowess as a thinker. The second is an attempt to recast Browning's religious and philosophical attitudes into the terms of evolutionism and skepticism
Stand-off runaway electron beam termination by tungsten particulates for tokamak disruption mitigation
Stand-off runaway electron termination by injected tungsten particulates
offers a plausible option in the toolbox of disruption mitigation. Tungsten is
an attractive material choice for this application due to large electron
stopping power and high melting point. To assess the feasibility of this
scheme, we simulate runaway collisions with tungsten particulates using the
MCNP program for incident runaway energies ranging from 1 to 10 MeV. We assess
runaway termination from energetics and collisional kinematics perspectives.
Energetically, the simulations show that 99% of runaway beam energy is removed
by tungsten particulates on a timescale of 4-9 s. Kinematically, the
simulations show that 99% of runaways are terminated by absorption or
backscattering on a timescale of 3-4 s. By either metric, the runaway beam
is effectively terminated before the onset of particulate melting. Furthermore,
the simulations show that secondary radiation emission by tungsten particulates
does not significantly impact the runaway termination efficacy of this scheme.
Secondary radiation is emitted at lower particle energies than the incident
runaways and with a broad angular distribution such that the majority of
secondary electrons emitted will not experience efficient runaway
re-acceleration. Overall, the stand-off runaway termination scheme is a
promising concept for last-ditch runaway mitigation in ITER, SPARC, and other
future burning-plasma tokamaks.Comment: Submitted to: Nuclear Fusion - 16 pages (4 supplementary), 11 figures
(5 supplementary), 4 table
Technology Readiness Level Assessment Process as Applied to NASA Earth Science Missions
Technology assessments of fourteen science instruments were conducted within NASA using the NASA Technology Readiness Level (TRL) Metric. The instruments were part of three NASA Earth Science Decadal Survey missions in pre-formulation. The Earth Systematic Missions Program (ESMP) Systems Engineering Working Group (SEWG), composed of members of three NASA Centers, provided a newly modified electronic workbook to be completed, with instructions. Each instrument development team performed an internal assessment of its technology status, prepared an overview of its instrument, and completed the workbook with the results of its assessment. A team from the ESMP SEWG met with each instrument team and provided feedback. The instrument teams then reported through the Program Scientist for their respective missions to NASA's Earth Science Division (ESD) on technology readiness, taking the SEWG input into account. The instruments were found to have a range of TRL from 4 to 7. Lessons Learned are presented; however, due to the competition-sensitive nature of the assessments, the results for specific missions are not presented. The assessments were generally successful, and produced useful results for the agency. The SEWG team identified a number of potential improvements to the process. Particular focus was on ensuring traceability to guiding NASA documents, including the NASA Systems Engineering Handbook. The TRL Workbook has been substantially modified, and the revised workbook is described
Apparatus, Methods and Systems For Fabricating Thin Nanoporous Membranes
Embodiments of the present disclosure provide apparatuses, methods and systems for scalable fabrication of thin, nanoporous membranes useful in industrial applications. One embodiment of the present disclosure provides a molecular separation device configured to efficiently separate molecular species. In this particular embodiment, porous hollow fibers form a supporting scaffold for synthesis of a molecular organic framework (MOF) membrane. The MOF membrane may be synthesized on the inner or outer porous hollow fiber surface as well as within the porous fiber wall. Embodiments of the present disclosure provide a variety of methods for producing the aforementioned molecular separation devices as well as methods for producing MOF membranes
20 Meter Solar Sail Analysis and Correlation
This presentation discusses studies conducted to determine the element type and size that best represents a 20-meter solar sail under ground-test load conditions, the performance of test/Analysis correlation by using Static Shape Optimization Method for Q4 sail, and system dynamic. TRIA3 elements better represent wrinkle patterns than do QUAD3 elements Baseline, ten-inch elements are small enough to accurately represent sail shape, and baseline TRIA3 mesh requires a reasonable computation time of 8 min. 21 sec. In the test/analysis correlation by using Static shape optimization method for Q4 sail, ten parameters were chosen and varied during optimization. 300 sail models were created with random parameters. A response surfaces for each targets which were created based on the varied parameters. Parameters were optimized based on response surface. Deflection shape comparison for 0 and 22.5 degrees yielded a 4.3% and 2.1% error respectively. For the system dynamic study testing was done on the booms without the sails attached. The nominal boom properties produced a good correlation to test data the frequencies were within 10%. Boom dominated analysis frequencies and modes compared well with the test results
Criteria for the use of omics-based predictors in clinical trials.
The US National Cancer Institute (NCI), in collaboration with scientists representing multiple areas of expertise relevant to 'omics'-based test development, has developed a checklist of criteria that can be used to determine the readiness of omics-based tests for guiding patient care in clinical trials. The checklist criteria cover issues relating to specimens, assays, mathematical modelling, clinical trial design, and ethical, legal and regulatory aspects. Funding bodies and journals are encouraged to consider the checklist, which they may find useful for assessing study quality and evidence strength. The checklist will be used to evaluate proposals for NCI-sponsored clinical trials in which omics tests will be used to guide therapy
A Class of Topological Actions
We review definitions of generalized parallel transports in terms of
Cheeger-Simons differential characters. Integration formulae are given in terms
of Deligne-Beilinson cohomology classes. These representations of parallel
transport can be extended to situations involving distributions as is
appropriate in the context of quantized fields.Comment: 41 pages, no figure
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