Turbulence driven particle transport in Texas Helimak

We analyze the turbulence driven particle transport in Texas Helimak (K. W. Gentle and Huang He, Plasma Sci. and Technology, 10, 284 (2008)), a toroidal plasma device with one-dimensional equilibrium with magnetic curvature and shear. Alterations on the radial electric field, through an external voltage bias, change spectral plasma characteristics inducing a dominant frequency for negative bias values and a broad band frequency spectrum for positive bias values. For negative biased plasma discharges, the transport is high where the waves propagate with phase velocities near the plasma flow velocity, an indication that the transport is strongly affected by a wave particle resonant interaction. On the other hand, for positive bias the plasma has a reversed shear flow and we observe that the transport is almost zero in the shearless radial region, an evidence of a transport barrier in this region.Comment: 8 pages, 11 figure

Faktor-faktor Yang Mempengaruhi Perilaku Konsumen Dalam Melakukan Pembelian Apartemen Di Surabaya

Penelitian ini bertujuan untuk mengetahui faktor-faktor yang mempengaruhi perilaku konsumen dalam melakukan pembelian apartemen di Surabaya. Data yang terkumpul melalui online survey yang dilakukan terhadap 110 konsumen apartemen Surabaya diolah menggunakan teknik Exploratory Factor Analysis (EFA). Hasil penelitian menunjukkan bahwa terdapat 7 (tujuh) faktor baru yang terbentuk yaitu lingkungan apartemen, motivasi pribadi, peran dan status sosial, additional benefits, kriteria apartemen, lokasi apartemen, dan prospek apartemen; dimana faktor lingkungan apartemen memiliki konstribusi terbesar yang mempengaruhi perilaku konsumen dalam melakukan pembelian apartemen di Surabaya.This research aims to find out factors that influence consumer behavior to purchase an apartment in Surabaya. Data which were collected through online survey from 110 apartment\u27s consumers in Surabaya were processed using Exploratory Factor Analysis (EFA) technique. The result shows that there are 7 new factors, which are apartment environment, personal motivation, role and social status, additional benefits, apartment criteria, apartment location and apartment prospect; in which environmental factor has the highest contribution in influencing consumer behavior to purchase an apartment in Surabaya

Exact 1/N and Optimized Perturbative Evaluation of mu_c for Homogeneous Interacting Bose Gases

In the framework of the O(N) three-dimensional effective scalar field model for homogeneous dilute weakly interacting Bose gases we use the 1/N expansion to evaluate, within the large N limit, the parameter r_c which is directly related to the critical chemical potential mu_c. This quantity enters the order-a^2 n^{2/3} coefficient contributing to the critical temperature shift Delta T_c where a represents the s-wave scattering length and n represents the density. Compared to the recent precise numerical lattice simulation results, our calculation suggests that the large N approximation performs rather well even for the physical case N=2. We then calculate the same quantity but using different forms of the optimized perturbative (variational) method, showing that these produce excellent results both for the finite N and large-N cases.Comment: 12 pages, 2 figures. We have performed a refined and extended numerical analysis to take into account the very recent results of Ref. [15

Covariant path integral for chiral p-forms

The covariant path integral for chiral bosons obtained by McClain, Wu and Yu is generalized to chiral p-forms. In order to handle the reducibility of the gauge transformations associated with the chiral p-forms and with the new variables (in infinite number) that must be added to eliminate the second class constraints, the field-antifield formalism is used.Comment: revtex, 9 pages, submitted to Physical Review

Soft-X-Ray Absorption Spectroscopy and Ab Initio Calculations

Nonradiative decay channels in the L-edge fluorescence yield spectra from transition-metal–aqueous solutions give rise to spectral distortions with respect to x-ray transmission spectra. Their origin is unraveled here using partial and inverse partial fluorescence yields on the microjet combined with multireference ab initio electronic structure calculations. Comparing Fe2+, Fe3+, and Co2+ systems we demonstrate and quantify unequivocally the state- dependent electron delocalization within the manifold of d orbitals as one origin of this observation

Propargyl alcohol as a corrosion inhibitor for AISI 304L stainless steel in hydrochloric acid

Hydrochloric acid solutions (at concentrations of 5 to 28%) are used to acidify or acid-stimulate a rock-reservoir, increasing productivity of an oil well and removing calcareous deposits that lodge inside the carbon steel pipes. Typically, AISI 304 L stainless steel is used to manufacture various components, such as valves, adapters, rings, connectors, and rotors of pumps that are used in these acidifications. In order to guarantee the protection of both the carbon steel and the AISI 304 L, propargyl alcohol can be used as a corrosion inhibitor. The results of mass loss (gravimetric) and electrochemical tests (polarization curve) show a good efficiency of propargyl alcohol as a corrosion inhibitor for AISI 304 L stainless steel in concentrations of 5% (by volume) and 10% (by volume) of hydrochloric acid

Averaging approach to phase coherence of uncoupled limit-cycle oscillators receiving common random impulses

Populations of uncoupled limit-cycle oscillators receiving common random impulses show various types of phase-coherent states, which are characterized by the distribution of phase differences between pairs of oscillators. We develop a theory to predict the stationary distribution of pairwise phase difference from the phase response curve, which quantitatively encapsulates the oscillator dynamics, via averaging of the Frobenius-Perron equation describing the impulse-driven oscillators. The validity of our theory is confirmed by direct numerical simulations using the FitzHugh-Nagumo neural oscillator receiving common Poisson impulses as an example

On the Phenomenology of Hydrodynamic Shear Turbulence

The question of a purely hydrodynamic origin of turbulence in accretion disks is reexamined, on the basis of a large body of experimental and numerical evidence on various subcritical (i.e., linearly stable) hydrodynamic flows. One of the main points of this paper is that the length scale and velocity fluctuation amplitude which are characteristic of turbulent transport in these flows scale like $Re_m^{-1/2}$, where $Re_m$ is the minimal Reynolds number for the onset of fully developed turbulence. From this scaling, a simple explanation of the dependence of $Re_m$ with relative gap width in subcritical Couette-Taylor flows is developed. It is also argued that flows in the shearing sheet limit should be turbulent, and that the lack of turbulence in all such simulations performed to date is most likely due to a lack of resolution, as a consequence of the effect of the Coriolis force on the large scale fluctuations of turbulent flows. These results imply that accretion flows should be turbulent through hydrodynamic processes. If this is the case, the Shakura-Sunyaev $\alpha$ parameter is constrained to lie in the range $10^{-3}-10^{-1}$ in accretion disks, depending on unknown features of the mechanism which sustains turbulence. Whether the hydrodynamic source of turbulence is more efficient than the MHD one where present is an open question.Comment: 31 pages, 3 figures. Accepted for publication in Ap