232 research outputs found
Bubble formation and growth - Study of the boundary conditions at a liquid-vapor interface through irreversible thermodynamics Quarterly progress report, Mar. - May 1966
Nonequilibrium effect on vapor bubble growth determined in study of boundary conditions at liquid-vapor interfac
Editorial for special issue âGeochemistry and mineralogy of hydrothermal metallic mineral depositsâ
The Special Issue of Minerals on Geochemistry and Mineralogy of Hydrothermal Metallic Mineral Deposits presents the results of diverse geochemical and mineralogical research from across the globe. It is aimed to demonstrate that geochemical and mineralogical variation, both within and among hydrothermal ore deposits can be applied to genetic models, to exploration and drilling programs, and more. The eight contributions reflect a wide range of deposits, as well as different types of geochemical and mineralogical research applied to them. While most of these studies are focused on gaining a better understanding of deposit genesis, the results have a far greater application, as highlighted below
Bubble formation and growth - Study of the boundary conditions at a liquid-vapor interface through irreversible thermodynamics Quarterly progress report, Jun. - Aug. 1966
Steady state mercury evaporation experiment to measure transport coefficient in liquid-vapor interface boundary condition stud
Sources of Hydrothermal Fluids Inferred from Oxygen and Carbon Isotope Composition of Calcite, Keweenaw Peninsula Native Copper District, Michigan, USA
The Mesoproterozoic North American Midcontinent Rift hosts the worldâs largest accu-mulation of native copper in Michiganâs Keweenaw Peninsula. During a regional metamorpho-genicâhydrothermal event, native copper was deposited along with spatially zoned mainâstage minerals in a thermal high. This was followed by deposition of lateâstage minerals including minor copper sulfide. Inferences from the oxygen and carbon isotopic composition of mainâstage hydrothermal fluids, as calculated from 296 new and compiled isotopic measurements on calcite, are consistent with existing models that lowâsulfur saline native copper oreâforming fluids were domi-nantly derived by burial metamorphic processes from the very low sulfur basaltâdominated rift fill at depth below the native copper deposits. Coâvariation of oxygen and carbon isotopic compositions are consistent with mixing of metamorphicâderived fluids with two additional isotopically different fluids. One of these is proposed to be evolved seawater that provided an outside source of salinity. This fluid mixed at depth and participated in the formation of a wellâmixed hybrid metamorphic-dominated oreâforming fluid. Secondary Ion Mass Spectrometry inâsitu isotopic analyses of calcite demonstrate a high degree of variability within samples that is attributed to variable degrees of shallow mixing of the hybrid oreâforming fluid with sulfurâpoor, reduced evolved meteoric water in the zone of precipitation. The oxygen and carbon isotopic compositions of 100 new and compiled measurements on lateâstage calcite are mostly isotopically different than the mainâstage hydrothermal fluids. The lateâstage hydrothermal fluids are interpreted as various proportions of mixing of evolved meteoric water, mainâstage hybrid oreâforming fluid, and shallow, evolved seawater in the relatively shallow zone of precipitation
End-to-end deep learning for directly estimating grape yield from ground-based imagery
Yield estimation is a powerful tool in vineyard management, as it allows
growers to fine-tune practices to optimize yield and quality. However, yield
estimation is currently performed using manual sampling, which is
time-consuming and imprecise. This study demonstrates the application of
proximal imaging combined with deep learning for yield estimation in vineyards.
Continuous data collection using a vehicle-mounted sensing kit combined with
collection of ground truth yield data at harvest using a commercial yield
monitor allowed for the generation of a large dataset of 23,581 yield points
and 107,933 images. Moreover, this study was conducted in a mechanically
managed commercial vineyard, representing a challenging environment for image
analysis but a common set of conditions in the California Central Valley. Three
model architectures were tested: object detection, CNN regression, and
transformer models. The object detection model was trained on hand-labeled
images to localize grape bunches, and either bunch count or pixel area was
summed to correlate with grape yield. Conversely, regression models were
trained end-to-end to predict grape yield from image data without the need for
hand labeling. Results demonstrated that both a transformer as well as the
object detection model with pixel area processing performed comparably, with a
mean absolute percent error of 18% and 18.5%, respectively on a representative
holdout dataset. Saliency mapping was used to demonstrate the attention of the
CNN model was localized near the predicted location of grape bunches, as well
as on the top of the grapevine canopy. Overall, the study showed the
applicability of proximal imaging and deep learning for prediction of grapevine
yield on a large scale. Additionally, the end-to-end modeling approach was able
to perform comparably to the object detection approach while eliminating the
need for hand-labeling
Effects of thermal fluctuation and the receptor-receptor interaction in bacterial chemotactic signalling and adaptation
Bacterial chemotaxis is controlled by the conformational changes of the
receptors, in response to the change of the ambient chemical concentration. In
a statistical mechanical approach, the signalling due to the conformational
changes is a thermodynamic average quantity, dependent on the temperature and
the total energy of the system, including both ligand-receptor interaction and
receptor-receptor interaction. This physical theory suggests to biology a new
understanding of cooperation in ligand binding and receptor signalling
problems. How much experimental support of this approach can be obtained from
the currently available data? What are the parameter values? What is the
practical information for experiments? Here we make comparisons between the
theory and recent experimental results. Although currently comparisons can only
be semi-quantitative or qualitative, consistency is clearly shown. The theory
also helps to sort a variety of data.Comment: 26 pages, revtex. Journal version. Analysis on another set of data on
adaptation time is adde
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