623 research outputs found
Small-Angle X-ray and neutron scattering from diamond single crystals
Results of Small-Angle Scattering study of diamonds with various types of
point and extended defects and different degrees of annealing are presented. It
is shown that thermal annealing and/or mechanical deformation cause formation
of nanosized planar and threedimensional defects giving rise to Small-Angle
Scattering. The defects are often facetted by crystallographic planes 111, 100,
110, 311, 211 common for diamond. The scattering defects likely consist of
clusters of intrinsic and impurity-related defects; boundaries of mechanical
twins also contribute to the SAS signal. There is no clear correlation between
concentration of nitrogen impurity and intensity of the scattering.Comment: 6 pages, 5 figures; presented at SANS-YuMO User Meeting 2011, Dubna,
Russi
A New Look at Pricing of the Russian Option
The âRussian optionâ was introduced and calculated with the help of the solution of the optimal stopping problem for a two-dimensional Markov process in [10]. This paper proposes a new derivation of the general results [10]. The key idea is to introduce the dual martingale measure which permits one to reduce the âtwo-dimensionalâ optimal stopping problem to a âone-dimensionalâ one. This approach simplifies the discussion and explain the simplicity of the answer found in [10]
Optimal Stopping Rules and Maximal Inequalities for Bessel Processes
We consider, for Bessel processes X â Besα with arbitrary order (dimension) α â R, the problem of the optimal stopping (1.4) for which the gain is determined by the value of the maximum of the process X and the cost which is proportional to the duration of the observation time. We give a description of the optimal stopping rule structure (Theorem 1) and the price (Theorem 2). These results are used for the proof of maximal inequalities of the type
E max Xrrâ€r †γ(α) is a constant depending on the dimension (order) α. It is shown that Îł(α) ⌠âα at α â â
The Resonance Peak in SrRuO: Signature of Spin Triplet Pairing
We study the dynamical spin susceptibility, , in the
normal and superconducting state of SrRuO. In the normal state, we find
a peak in the vicinity of in agreement with
recent inelastic neutron scattering (INS) experiments. We predict that for spin
triplet pairing in the superconducting state a {\it resonance peak} appears in
the out-of-plane component of , but is absent in the in-plane component.
In contrast, no resonance peak is expected for spin singlet pairing.Comment: 4 pages, 4 figures, final versio
Incorporating Inertia Into Multi-Agent Systems
We consider a model that demonstrates the crucial role of inertia and
stickiness in multi-agent systems, based on the Minority Game (MG). The inertia
of an agent is introduced into the game model by allowing agents to apply
hypothesis testing when choosing their best strategies, thereby reducing their
reactivity towards changes in the environment. We find by extensive numerical
simulations that our game shows a remarkable improvement of global cooperation
throughout the whole phase space. In other words, the maladaptation behavior
due to over-reaction of agents is removed. These agents are also shown to be
advantageous over the standard ones, which are sometimes too sensitive to
attain a fair success rate. We also calculate analytically the minimum amount
of inertia needed to achieve the above improvement. Our calculation is
consistent with the numerical simulation results. Finally, we review some
related works in the field that show similar behaviors and compare them to our
work.Comment: extensively revised, 8 pages, 10 figures in revtex
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