2,187 research outputs found
The structure and composition of exhumed faults, and their implications for seismic processes
Field studies of faults exhumed from seismogenic depths provide useful data to constrain seismologic models of fault zone processes and properties. Data collected on the
San Andreas Fault in the San Gabriel Mountains has shown that large-displacement faults consist of one to several very narrow slip zones embedded in a cataclastically deformed sheared region several meters thick. However these faults have not been buried to depths greater than 5 km. Fault zones in the Sierra Nevada, California allow us to study the microstructures resulting from the deformation mechanisms active at seismogenic depths. Syn-fault mineralization shows that these left-lateral strike-slip faults formed at 5-12 km depth. Detailed microstructural analyses of the small faults reveal that they evolved from
cooling joints filled by chlorite, epidote and quartz. These joints were then reactivated to form shear faults with accompanying brittle fracture and cataclastic deformation, ultimately developing very fined-grained cataclasites and ultracataclasites. The shear-induced
microstructures are developed on faults with as little as several mm of slip showing that narrow slip-surfaces develop early in the lifetime of these faults. Subsequent slip has little effect on the microstructures. The inferred similarity of deformation mechanisms in faults 10
m to 10 km long indicates that basic slip processes on the faults are scale invariant, and may be a cause for the inferred constant b-value for small earthquakes. Analysis of map-scale fault linkages and terminations indicate that linkage zones are up to 400 m wide and 1 km long, and consist of altered and fractured rocks with numerous through-going slip surfaces. Terminations are regions of numerous splay faults that have cumulative offsets approaching those of the main faults. The slip distribution and structure of the terminations and linkage zones suggest that seismic slip may propagate into these zones of enhanced toughness, and that through-going slip can occur when a sufficient linkage of faults in the zone allow slip to be transmitted
On the forward-backward correlations in a two-stage scenario
It is demonstrated that in a two-stage scenario with elementary Poissonian
emitters of particles (colour strings) arbitrarily distributed in their number
and average multiplicities, the forward- backward correlations are completely
determined by the final distribution of the forward particles. The observed
linear form of the correlations then necessarily requires this distribution to
have a negative binomial form. For emitters with a negative binomial
distribution of the produced particles distributed so as to give the final
distribution also of a negative binomial form, the forward-backward
correlations have an essentially non-linear form, which disagrees with the
experimental data.Comment: 14 pages in LaTex, 1 figure in Postscrip
Fluidized Bed Membrane Reactor for Steam Reforming of Higher Hydrocarbons: Model Sensitivity
A fluidized bed membrane reactor (FBMR) was built and operated at temperatures \u3c600°C to reform higher hydrocarbons like propane and heptane. A two-phase reactor model is utilized to simulate the FBMR with hydrogen withdrawn from both phases. The superficial gas velocities in the reactor change because of variations in molar flow due to reaction and hydrogen withdrawal through the membranes, as well as variations in temperature, pressure and cross-sectional area. Sensitivity studies show that the FBMR performance is primarily controlled by chemical equilibrium and hydrogen permeation through the membranes, while being insensitive to errors in accurately characterizing the chemical kinetics and hydrodynamics
Two-jet inclusive cross sections in heavy-ion collisions in the perturbative QCD
In the framework of perturbative QCD, double inclusive cross sections for
high parton production in nucleus-nucleus collisions are computed with
multiple rescattering taken into account. The induced long-range correlations
between numbers of jets at forward and backward rapidities are found to reach
% for light nuclei at GeV/c and to be suppressed for
heavy nuclei and LHC energies.Comment: 17 pages, 6 figures. V2: Major revision
Self-consistent simulation of high-brightness diode lasers with external optical feedback
This paper presents a model for simulating the impact of external optical feedback on large-optical cavity high-brightness diode lasers. The simulations are performed with our 2.5D simulation tool for high-brightness laser diodes. The external cavity is modelled using commercial coherent ray tracing software. We consider the impact of the optical feedback on the excitation of amplified spontaneous emission in the parasitic vertical modes
Isolation of mitochondrial control region for white-nest swiftlets (Aerodramus fuciphagus) using primer walking techniques
This paper reports on a novel DNA sequence located at the mitochondrial control region (D-loop) of the white-nest swiftlet (Aerodramus fuciphagus). This hypervariable control region sequence is potentially useful for studying genetic relationships among the white-nest swiftlet populations. The isolation of the control region involves a primer walking technique, which is simple, fast and cost-effective. In this study, the variability of the control region was assessed and discussed
Measurement of K^+ \to \pi^0 \mu^+ \nu \gamma decay using stopped kaons
The K^+ \to \pi^0 \mu^+ \nu \gamma () decay has been
measured with stopped positive kaons at the KEK 12 GeV proton synchrotron. A
sample containing 125 events was obtained. The partial
branching ratio was found to be , which is in good agreement with theoretical predictions.Comment: 12 pages, 3 figures, to be published in Physics Letters
A genetic algorithm for berth allocation and quay crane assignment
13th Ibero-American Conference on Artificial Intelligence. IBERAMIA 2012, Cartagena de Indias, Colombia. 13-16 November 2012The final publication is available at Springer via http://dx.doi.org/10.1007/978-3-642-34654-5_61Container terminals are facilities where cargo containers are transshipped between different transport vehicles, for onward transportation. They are open systems that carry out a large number of different combinatorial problems that can be solved by means of Artificial Intelligence techniques. In this work, we focus our attention on scheduling a number of incoming vessels by assigning to each a berthing position, a mooring time and a number of Quay Cranes. This problem is known as the Berthing Allocation and Quay Crane Assignment problem. To formulate the problem, we first propose a mixed integer linear programming model to minimize the total weighted service time of the incoming vessels. Then, a meta-heuristic algorithm (Genetic Algorithm (GA)) is presented for solving the proposed problem. Computational experiments are performed to evaluate the effectiveness and efficiency of the proposed metho
Measurement of direct photon emission in decay using stopped positive kaons
The radiative decay () has
been measured with stopped positive kaons. A sample
containing 4k events was analyzed, and the branching ratio
of the direct photon emission process was determined to be . No interference pattern with internal
bremsstrahlung was observed.Comment: 12 pages, 6 figures, 2 tables, to be published in Phys. Lett.
Game Theoretical Interactions of Moving Agents
Game theory has been one of the most successful quantitative concepts to
describe social interactions, their strategical aspects, and outcomes. Among
the payoff matrix quantifying the result of a social interaction, the
interaction conditions have been varied, such as the number of repeated
interactions, the number of interaction partners, the possibility to punish
defective behavior etc. While an extension to spatial interactions has been
considered early on such as in the "game of life", recent studies have focussed
on effects of the structure of social interaction networks.
However, the possibility of individuals to move and, thereby, evade areas
with a high level of defection, and to seek areas with a high level of
cooperation, has not been fully explored so far. This contribution presents a
model combining game theoretical interactions with success-driven motion in
space, and studies the consequences that this may have for the degree of
cooperation and the spatio-temporal dynamics in the population. It is
demonstrated that the combination of game theoretical interactions with motion
gives rise to many self-organized behavioral patterns on an aggregate level,
which can explain a variety of empirically observed social behaviors
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