2,275 research outputs found
Game Theoretic Approaches to Massive Data Processing in Wireless Networks
Wireless communication networks are becoming highly virtualized with
two-layer hierarchies, in which controllers at the upper layer with tasks to
achieve can ask a large number of agents at the lower layer to help realize
computation, storage, and transmission functions. Through offloading data
processing to the agents, the controllers can accomplish otherwise prohibitive
big data processing. Incentive mechanisms are needed for the agents to perform
the controllers' tasks in order to satisfy the corresponding objectives of
controllers and agents. In this article, a hierarchical game framework with
fast convergence and scalability is proposed to meet the demand for real-time
processing for such situations. Possible future research directions in this
emerging area are also discussed
Constructive Lower Bounds on Classical Multicolor Ramsey Numbers
This paper studies lower bounds for classical multicolor Ramsey numbers, first by giving a short overview of past results, and then by presenting several general constructions establishing new lower bounds for many diagonal and off-diagonal multicolor Ramsey numbers. In particular, we improve several lower bounds for R_k(4) and R_k(5) for some small k, including 415 \u3c = R_3(5), 634 \u3c = R_4(4), 2721 \u3c = R_4(5), 3416 \u3c = R_5(4) and 26082 \u3c = R_5(5). Most of the new lower bounds are consequences of general constructions
High density loading and collisional loss of laser cooled molecules in an optical trap
We report optical trapping of laser-cooled molecules at sufficient density to
observe molecule-molecule collisions for the first time in a bulk gas. SrF
molecules from a red-detuned magneto-optical trap (MOT) are compressed and
cooled in a blue-detuned MOT. Roughly 30% of these molecules are loaded into an
optical dipole trap with peak number density and temperature K. We observe two-body loss
with rate coefficient . Achieving this density and temperature opens a path to
evaporative cooling towards quantum degeneracy of laser-cooled molecules.Comment: 6+6 pages, 4+3 figures (main text + supplemental material
Steady shape analysis of tomographic pumping tests for characterization of aquifer heterogeneities
This is the published version. Copyright American Geophysical Union[1] Hydraulic tomography, a procedure involving the performance of a suite of pumping tests in a tomographic format, provides information about variations in hydraulic conductivity at a level of detail not obtainable with traditional well tests. However, analysis of transient data from such a suite of pumping tests represents a substantial computational burden. Although steady state responses can be analyzed to reduce this computational burden significantly, the time required to reach steady state will often be too long for practical applications of the tomography concept. In addition, uncertainty regarding the mechanisms driving the system to steady state can propagate to adversely impact the resulting hydraulic conductivity estimates. These disadvantages of a steady state analysis can be overcome by exploiting the simplifications possible under the steady shape flow regime. At steady shape conditions, drawdown varies with time but the hydraulic gradient does not. Thus transient data can be analyzed with the computational efficiency of a steady state model. In this study, we demonstrate the value of the steady shape concept for inversion of hydraulic tomography data and investigate its robustness with respect to improperly specified boundary conditions
Spatially Resolved Far-Ultraviolet Spectroscopy of the Nuclear Region of NGC 1068
We carry out high-resolution FUSE spectroscopy of the nuclear region of NGC
1068. The first set of spectra was obtained with a 30" square aperture that
collects all emission from the narrow-line region. The data reveal a strong
broad OVI component of FWHM ~3500 kms-1 and two narrow OVI 1031/1037 components
of ~350 kms-1. The CIII 977 and NIII 991 emission lines in this spectrum can be
fitted with a narrow component of FWHM ~1000 kms-1 and a broad one of ~2500
kms-1. Another set of seven spatially resolved spectra were made using a long
slit of 1.25" X 20", at steps of ~1" along the axis of the emission-line cone.
We find that (1) Major emission lines in the FUSE wavelength range consist of a
broad and a narrow component; (2) There is a gradient in the velocity field for
the narrow OVI component of ~200 kms-1 from ~2" southwest of the nucleus to ~4"
northeast. A similar pattern is also observed with the broad OVI component,
with a gradient of ~3000 kms-1. These are consistent with the HST/STIS findings
and suggest a biconical structure in which the velocity field is mainly radial
outflow; (3) A major portion of the CIII and NIII line flux is produced in the
compact core. They are therefore not effective temperature diagnostics for the
conical region; and (4) The best-fitted UV continuum suggests virtually no
reddening, and the HeII 1085/1640 ratio suggests a consistently low extinction
factor across the cone.Comment: To appear in the Astrophysical Journal. 37 pages with 12 figure
Kirigami-inspired, highly stretchable micro-supercapacitor patches fabricated by laser conversion and cutting.
The recent developments in material sciences and rational structural designs have advanced the field of compliant and deformable electronics systems. However, many of these systems are limited in either overall stretchability or areal coverage of functional components. Here, we design a construct inspired by Kirigami for highly deformable micro-supercapacitor patches with high areal coverages of electrode and electrolyte materials. These patches can be fabricated in simple and efficient steps by laser-assisted graphitic conversion and cutting. Because the Kirigami cuts significantly increase structural compliance, segments in the patches can buckle, rotate, bend and twist to accommodate large overall deformations with only a small strain (<3%) in active electrode areas. Electrochemical testing results have proved that electrical and electrochemical performances are preserved under large deformation, with less than 2% change in capacitance when the patch is elongated to 382.5% of its initial length. The high design flexibility can enable various types of electrical connections among an array of supercapacitors residing in one patch, by using different Kirigami designs
Relative importance of dispersion and rate-limited mass transfer in highly heterogeneous porous media: Analysis of a new tracer test at the Macrodispersion Experiment (MADE) site
This is the published version. Copyright American Geophysical Union[1] A single-well injection-withdrawal (SWIW) bromide tracer test was conducted to further investigate transport processes at the Macrodispersion Experiment (MADE) site on Columbus Air Force Base in Mississippi. The bromide breakthrough curve is highly asymmetric and exhibits an early time high-concentration peak followed by an extended period of low-concentration tailing. Comparisons of results simulated by advection-dispersion (AD) and dual-domain mass transfer (DDMT) models with the field data show that the DDMT model more accurately represents the magnitudes of both the early high-concentration peak and the later low-concentration tail. For both the AD and DDMT models, the match with field data is enhanced by incorporating hydraulic conductivity information from new direct-push profiling methods. The Akaike information criterion for the DDMT models is much smaller than that for the AD models in both the homogeneous and heterogeneous cases investigated in this work. The improved match of the DDMT model with the SWIW test data supports the hypothesis of mass transfer processes occurring at this highly heterogeneous site
The TATA Binding Protein in the Sea Urchin Embryo Is Maternally Derived
AbstractThe cDNA encoding the TATA binding protein was isolated from 8- to 16-cell and morula-stage embryonic libraries of two distantly related species of sea urchin,Strongylocentrotus purpuratusandLytechinus variegatus,respectively. The two proteins are 96% identical over both the N- and C-terminal domains, suggesting a conservation of transcriptional processes between the two species. The prevalence of SpTBP transcripts at several developmental time points was determined using the tracer excess titration method, and the corresponding number of TBP protein molecules was determined by quantitative Western blot analysis. Our results indicate that the amount of TBP mRNA and protein per embryo remains relatively constant throughout development. An initial large pool of TBP protein (>109) molecules in the egg becomes diluted as a consequence of cell division and decreases to about 2 × 106molecules per cell by the gastrula stage. We found byin situRNA hybridization that the oocyte contains a large amount of TBP mRNA which is depleted late in oogenesis so that the eggs and early embryos have extremely low levels of TBP mRNA. We conclude that the oocyte manufactures nearly all of the TBP protein necessary for embryogenesis
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