792 research outputs found
Dynamic asset trees and Black Monday
The minimum spanning tree, based on the concept of ultrametricity, is
constructed from the correlation matrix of stock returns. The dynamics of this
asset tree can be characterised by its normalised length and the mean
occupation layer, as measured from an appropriately chosen centre called the
`central node'. We show how the tree length shrinks during a stock market
crisis, Black Monday in this case, and how a strong reconfiguration takes
place, resulting in topological shrinking of the tree.Comment: 6 pages, 3 eps figues. Elsevier style. Will appear in Physica A as
part of the Bali conference proceedings, in pres
Selective & Simultaneous Determinations of Cu(II) & Pd(II) with 3-(o-Carboxyphenyl)-I-phenyltriazene N-Oxide & Cu(II) Determination in Ore & Alloys
816-81
Dynamic asset trees and portfolio analysis
The minimum spanning tree, based on the concept of ultrametricity, is
constructed from the correlation matrix of stock returns and provides a
meaningful economic taxonomy of the stock market. In order to study the
dynamics of this asset tree we characterize it by its normalized length and by
the mean occupation layer, as measured from an appropriately chosen center. We
show how the tree evolves over time, and how it shrinks particularly strongly
during a stock market crisis. We then demonstrate that the assets of the
optimal Markowitz portfolio lie practically at all times on the outskirts of
the tree. We also show that the normalized tree length and the investment
diversification potential are very strongly correlated.Comment: 9 pages, 3 figures (encapsulated postscript
Reheating furnace's soaking zone hearth refractories - a rational approach
The technology of steel processing subsequent to ingot casting, follows heating in soaking pit and rolling to form blooms, billets etc. Further reduction is carried out through heating and rolling to yield the final usable products. Reheating furnaces are used in reheating the "Semis" before they are used in secondary-processing
Visualizations for an Explainable Planning Agent
In this paper, we report on the visualization capabilities of an Explainable
AI Planning (XAIP) agent that can support human in the loop decision making.
Imposing transparency and explainability requirements on such agents is
especially important in order to establish trust and common ground with the
end-to-end automated planning system. Visualizing the agent's internal
decision-making processes is a crucial step towards achieving this. This may
include externalizing the "brain" of the agent -- starting from its sensory
inputs, to progressively higher order decisions made by it in order to drive
its planning components. We also show how the planner can bootstrap on the
latest techniques in explainable planning to cast plan visualization as a plan
explanation problem, and thus provide concise model-based visualization of its
plans. We demonstrate these functionalities in the context of the automated
planning components of a smart assistant in an instrumented meeting space.Comment: PREVIOUSLY Mr. Jones -- Towards a Proactive Smart Room Orchestrator
(appeared in AAAI 2017 Fall Symposium on Human-Agent Groups
Quantum entanglement: The unitary 8-vertex braid matrix with imaginary rapidity
We study quantum entanglements induced on product states by the action of
8-vertex braid matrices, rendered unitary with purely imaginary spectral
parameters (rapidity). The unitarity is displayed via the "canonical
factorization" of the coefficients of the projectors spanning the basis. This
adds one more new facet to the famous and fascinating features of the 8-vertex
model. The double periodicity and the analytic properties of the elliptic
functions involved lead to a rich structure of the 3-tangle quantifying the
entanglement. We thus explore the complex relationship between topological and
quantum entanglement.Comment: 4 pages in REVTeX format, 2 figure
Indentation Response and Contact Damage of Hard T-B-N Films Deposited by Magnetron Sputtering
Titanium-boron-nitride (Ti-B-N) films were deposited by reactive magnetron sputtering using a single TiB2 target. The films were deposited under different Ar:N2 ratios. The instrumented indentation technique (nanoindentation), is used to evaluate the mechanical properties of the films. A methodology is presented to evaluate the critical load to failure directly from the load depth curves. Significant effect of Ar:N2 ratio was observed on the mechanical properties of the Ti-B-N films
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