8,510 research outputs found
Contract net protocol for cooperative optimisation and dynamic scheduling of steel production
Electrical conduction of silicon oxide containing silicon quantum dots
Current-voltage measurements have been made at room temperature on a Si-rich
silicon oxide film deposited via Electron-Cyclotron Resonance Plasma Enhanced
Chemical Vapor Deposition (ECR-PECVD) and annealed at 750 - 1000C. The
thickness of oxide between Si quantum dots embedded in the film increases with
the increase of annealing temperature. This leads to the decrease of current
density as the annealing temperature is increased. Assuming the Fowler-Nordheim
tunneling mechanism in large electric fields, we obtain an effective barrier
height of 0.7 0.1 eV for an electron tunnelling
through an oxide layer between Si quantum dots. The Frenkel-Poole effect can
also be used to adequately explain the electrical conduction of the film under
the influence of large electric fields. We suggest that at room temperature Si
quantum dots can be regarded as traps that capture and emit electrons by means
of tunneling.Comment: 14 pages, 5 figures, submitted to J. Phys. Conden. Mat
Analisis Kelayakan USAha Aspek Finansial Penangkapan Mini Purse Seine dengan Ukuran Jaring yang Berbeda di Ppi Ujungbatu Kabupaten Jepara
Mini purse seine is a productive fishing gear in catching pelagic fishes. Potencial resources utilization could be increased by adding the size length and width of the nets. Therefore it needed to be analyzed the feasibility rate of those mini purse seines. The purposes of this research were to analyze study feasibility aspect (PP, R/C ratio, NPV, and IRR) of mini purse seine with nets different size in PPI Ujungbatu Jepara Regency and to analyze nets different size impact against NPV, R/C ratio and IRR of mini purse seines in PPI Ujungbatu Jepara Regency. The method used in this research was descriptive method by case study and data was collected through direct observation, interviewed, and literature study. The results of feasibility aspect obtained that marine fisheries business using mini purse seine with length 450 m (width 90 m) the average values of PP, R/C ratio, NPV, and IRR were 2,22 years, 1,17, Rp.454.423.108,64, and 38,56%. Mean while in marine fishing business using mini purse seine with length of the nets 360 m (width 75 m) The analysis results of feasibility aspect obtained that the average values of PP, R/C ratio, NPV, and IRR were 2,25 years, 1,16, Rp.394.713.135,15, and 38,33%. From those analysis concluded that fishing business using mini purse seine with different size of nets in PPI Ujungbatu Jepara Regency are feasible
Bound states of 3He at the edge of a 4He drop on a cesium surface
We show that small amounts of 3He atoms, added to a 4He drop deposited on a
flat cesium surface at zero temperature, populate bound states localized at the
contact line. These edge states show up for drops large enough to develop well
defined surface and bulk regions together with a contact line, and they are
structurally different from the well-known Andreev states that appear at the
free surface and at the liquid-solid interface of films. We illustrate the
one-body density of 3He in a drop with 1000 4He atoms, and show that for
sufficiently large number of impurities, the density profiles spread beyond the
edge, coating both the curved drop surface and its flat base and eventually
isolating it from the substrate.Comment: 10 pages and 7 figures. Submitted to PR
Covariant Coordinate Transformations on Noncommutative Space
We show how to define gauge-covariant coordinate transformations on a
noncommuting space. The construction uses the Seiberg-Witten equation and
generalizes similar results for commuting coordinates.Comment: 11 pages, LaTeX; email correspondence to [email protected]
Intricacies of the Co spin state in SrCoIrO: an x-ray absorption and magnetic circular dichroism study
We report on a combined soft x-ray absorption and magnetic circular dichroism
(XMCD) study at the Co- on the hybrid 3/5 solid state oxide
SrCoIrO with the KNiF structure. Our data
indicate unambiguously a pure high spin state for the Co
(3) ions with a significant unquenched orbital moment
despite the sizeable elongation of the CoO octahedra. Using quantitative
model calculations based on parameters consistent with our spectra, we have
investigated the stability of this high spin state with respect to the
competing low spin and intermediate spin states.Comment: 7 pages, 4 figure
A vertical diatomic artificial molecule in the intermediate coupling regime in a parallel and perpendicular magnetic field
We present experimental results for the ground state electrochemical
potentials of a few electron semiconductor artificial molecule made by
vertically coupling two quantum dots, in the intermediate coupling regime, in
perpendicular and parallel magnetic fields up to 5 T. We perform a quantitative
analysis based on local-spin density functional theory. The agreement between
theoretical and experimental results is good, and the phase transitions are
well reproduced.Comment: Typeset using Revtex, 13 pages and 8 Postscript figure
Remote Sensing-Driven Pacific Oyster (Crassostrea gigas) Growth Modeling to Inform Offshore Aquaculture Site Selection
Aquaculture increasingly contributes to global seafood production, requiring new farm sites for continued growth. In France, oyster cultivation has conventionally taken place in the intertidal zone, where there is little or no further room for expansion. Despite interest in moving production further offshore, more information is needed regarding the biological potential for offshore oyster growth, including its spatial and temporal variability. This study shows the use of remotely-sensed chlorophyll-a and total suspended matter concentrations retrieved from the Medium Resolution Imaging Spectrometer (MERIS), and sea surface temperature from the Advanced Very High Resolution Radiometer (AVHRR), all validated using in situ matchup measurements, as input to run a Dynamic Energy Budget (DEB) Pacific oyster growth model for a study site along the French Atlantic coast (Bourgneuf Bay, France). Resulting oyster growth maps were calibrated and validated using in situ measurements of total oyster weight made throughout two growing seasons, from the intertidal zone, where cultivation currently takes place, and from experimental offshore sites, for both spat (R2 = 0.91; RMSE = 1.60 g) and adults (R2 = 0.95; RMSE = 4.34 g). Oyster growth time series are further digested into industry-relevant indicators, such as time to achieve market weight and quality index, elaborated in consultation with local producers and industry professionals, and which are also mapped. Offshore growth is found to be feasible and to be as much as two times faster than in the intertidal zone (p < 0.001). However, the potential for growth is also revealed to be highly variable across the investigated area. Mapping reveals a clear spatial gradient in production potential in the offshore environment, with the northeastern segment of the bay far better suited than the southwestern. Results also highlight the added value of spatiotemporal data, such as satellite image time series, to drive modeling in support of marine spatial planning. The current work demonstrates the feasibility and benefit of such a coupled remote sensing modeling approach within a shellfish farming context, responding to real and current interests of oyster producers
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