6,869 research outputs found
Intermolecular Forces and the Glass Transition
Random first order transition theory is used to determine the role of
attractive and repulsive interactions in the dynamics of supercooled liquids.
Self-consistent phonon theory, an approximate mean field treatment consistent
with random first order transition theory, is used to treat individual glassy
configurations, while the liquid phase is treated using common liquid state
approximations. The transition temperature , the temperature where
the onset of activated behavior is predicted by mean field theory, the lower
crossover temperature where barrierless motions actually occur
through fractal or stringy motions, and , the Kauzmann temperature,
are calculated in addition to , the glass transition temperature
that corresponds to laboratory cooling rates. Both the isobaric and isochoric
behavior in the supercooled regime are studied, providing results for and that can be used to calculate the fragility as a
function of density and pressure, respectively. The predicted variations in the
-relaxation time with temperature and density conform to the empirical
density-temperature scaling relations found by Casalini and Roland. We thereby
demonstrate the microscopic origin of their observations. Finally, the
relationship first suggested by Sastry between the spinodal temperature and the
Kauzmann temperatures, as a function of density, is examined. The present
microscopic calculations support the existence of an intersection of these two
temperatures at sufficiently low temperatures.Comment: Submitted to J. Phys. Chem. A, June 2007 Replaced with accepted
version Sept. 200
Assessing Demographic Changes and Income Inequalities: A Case Study of West Virginia
This study investigates demographic change and income inequalities, and relationship between economic growth and income inequality in West Virginia. Income growth was positively related with population and employment growth, but is significantly and negatively related with income inequality. This indicates that higher income inequality is associated with slower economic growth.Labor and Human Capital,
Detecting -phase superfluids with -wave symmetry in a quasi-1D optical lattice
We propose an experimental protocol to study -wave superfluidity in a
spin-polarized cold Fermi gas tuned by an -wave Feshbach resonance. A
crucial ingredient is to add a quasi-1D optical lattice and tune the fillings
of two spins to the and band, respectively. The pairing order parameter
is confirmed to inherit -wave symmetry in its center-of-mass motion. We find
that it can further develop into a state of unexpected -phase modulation
in a broad parameter regime. Measurable quantities are calculated, including
time-of-flight distributions, radio-frequency spectra, and in situ
phase-contrast imaging in an external trap. The -phase -wave superfluid
is reminiscent of the -state in superconductor-ferromagnet
heterostructures but differs in symmetry and origin. If observed, it would
represent another example of -wave pairing, first discovered in He-3
liquids.Comment: 5 pages, 5 figure
THE ROLE OF SMALL BUSINESS IN ECONOMIC GROWTH AND POVERTY ALLEVIATION IN WEST VIRGINIA: AN EMPIRICAL ANALYSIS
In OLS and 2SLS regression analysis a positive relationship exists between small business and economic growth. A strong inverse relationship also exists between the incidence of poverty and small business and economic growth. Thus, the empirical result establishes the linkage between small business, economic growth and the incidence of povertyResearch Methods/ Statistical Methods,
Is Income Inequality Endogenous in Regional Growth?
This study focuses on testing the relationship between income inequality and growth within U.S. counties, and the channels through which such effects are observed. The study tests three hypotheses: (1) income inequality has an inverse relationship with growth; (2) regional growth adjustments are the channels through which the inequality and growth are equilibrated; and (3) income inequality is endogenous to regional growth and its adjustment. Results, based on a system of equations estimation, confirm the hypotheses that income inequality has a growth dampening effect; income inequality is endogenous to regional growth and growth adjustment; and the channels through which income inequality determines growth are regional growth adjustments, such as migration and regional adjustment in job and income growth. Results have numerous policy implications: (1) to the extent that income inequality is endogenous, its equilibrium level can be internally determined within a regional growth process; (2) to the extent that traditional income inequality mitigating policies have indirect effect on overall regional growth, they may have unintended indirect effects on income inequality; and (3) to the extent that regional growth adjustment also equilibrates income inequality, such forces can be utilized as policy instruments to mitigate income inequality, and its growth dampening effects hence forth.Income inequality, economic growth, Gini coefficient, growth modeling, population change, per capita income, Community/Rural/Urban Development, Public Economics, I32, J15, O18, P25, R11, R23, R25, R51, R53, R58,
Neonatal growth of Steller sea lion (Eumetopias jubatus) pups in Alaska
The growth rate of Steller sea lion (Eumetopias jubatus) pups was studied in southeast Alaska, the Gulf of Alaska, and the Aleutian Islands during the first six weeks after birth. The Steller sea lion population is currently stable in southeast Alaska but is declining in the Aleutian Islands and parts of the Gulf of Alaska. Male pups (22.6 kg [±2.21 SD]) were significantly heavier than female pups (19.6 kg [±1.80 SD]) at 1−5 days of age, but there were no significant differences among rookeries. Male and female pups grew (in mass, standard length, and axillary girth) at the same rate. Body mass and standard length increased at a faster rate for pups in the Aleutian Islands and the western Gulf of Alaska (0.45−0.48 kg/day and 0.47−0.53 cm/day, respectively) than in southeast Alaska (0.23 kg/day and 0.20 cm/day). Additionally, axillary girth increased at a faster rate for pups in the Aleutian Islands (0.59 cm/ day) than for pups in southeast Alaska v(0.25 cm/day). Our results indicate a greater maternal investment in male pups during gestation, but not during early lactation. Although differences in pup growth rate occurred among rookeries, there was no evidence that female sea lions and their pups were nutritionally stressed in the area of population declin
Spatial Interference Cancelation for Mobile Ad Hoc Networks: Perfect CSI
Interference between nodes directly limits the capacity of mobile ad hoc
networks. This paper focuses on spatial interference cancelation with perfect
channel state information (CSI), and analyzes the corresponding network
capacity. Specifically, by using multiple antennas, zero-forcing beamforming is
applied at each receiver for canceling the strongest interferers. Given spatial
interference cancelation, the network transmission capacity is analyzed in this
paper, which is defined as the maximum transmitting node density under
constraints on outage and the signal-to-interference-noise ratio. Assuming the
Poisson distribution for the locations of network nodes and spatially i.i.d.
Rayleigh fading channels, mathematical tools from stochastic geometry are
applied for deriving scaling laws for transmission capacity. Specifically, for
small target outage probability, transmission capacity is proved to increase
following a power law, where the exponent is the inverse of the size of antenna
array or larger depending on the pass loss exponent. As shown by simulations,
spatial interference cancelation increases transmission capacity by an order of
magnitude or more even if only one extra antenna is added to each node.Comment: 6 pages; submitted to IEEE Globecom 200
Measuring Organizational Effectiveness: The Role Of The Organizational Community Index
The purpose of this research is to help understand the value of presuppositions through the development of a community index for organizations, that employees bring certain community appeals to organizational life. Those appeals are entrenched in ancestral paradigms of the past as a natural part of the human psyche (Nicholson, 1997). This research attempts to understand the appeals with the development of the Organizational Community Index (OCI) with three subscales: Measure of Influence; Sense of Belonging; and Feeling of Recognition. The subscales were developed based on previous research from the influence of anthropology, sociology, and psychology on organizational studies. One hundred and forty-six business professionals were surveyed as an initial sample. Results of reliability coefficients, skewness, and kurtosis indicated that the subscales are reliable and serve psychometric purposes. The OCI should be further tested with larger samples sizes and in a variety of organizations. Initial conclusions suggest that organizations might want to assess their sense of community among employees before they proceed with planned change involving organizational effectiveness
Solvent Influence on Atomic Spectra: The Effect of Finite Size
Time dependent Hartree theory is used to determine the solvent effect on atomic spectra for a given solvent configuration. Configuration averaging is performed as in the mean spherical approximation, resulting in an upper bound to the polarizability. Comparisons are made with previous, more approximate theories, including path integral treatments. It is found that deviations from previous theories can be significant in certain regimes
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