12,143 research outputs found
Higher Toda brackets and the Adams spectral sequence in triangulated categories
The Adams spectral sequence is available in any triangulated category
equipped with a projective or injective class. Higher Toda brackets can also be
defined in a triangulated category, as observed by B. Shipley based on J.
Cohen's approach for spectra. We provide a family of definitions of higher Toda
brackets, show that they are equivalent to Shipley's, and show that they are
self-dual. Our main result is that the Adams differential in any Adams
spectral sequence can be expressed as an -fold Toda bracket and as an
order cohomology operation. We also show how the result
simplifies under a sparseness assumption, discuss several examples, and give an
elementary proof of a result of Heller, which implies that the three-fold Toda
brackets in principle determine the higher Toda brackets.Comment: v2: Added Section 7, about an application to computing maps between
modules over certain ring spectra. Minor improvements elsewhere. v3: Minor
updates throughout; closely matches published versio
Sensitivity to initial conditions in self-organized critical systems
We discuss sensitivity to initial conditions in a model for avalanches in
granular media displaying self-organized criticality. We show that damage, due
to a small perturbation in initial conditions, does not spread. The damage
persists in a statistically time-invariant and scale-free form. We argue that
the origin of this behavior is the Abelian nature of the model, which
generalizes our results to all Abelian models, including the BTW model and the
Manna model. An ensemble average of the damage leads to seemingly time
dependent damage spreading. Scaling arguments show that this numerical result
is due to the time lag before avalanches reach the initial perturbation.Comment: 4 pages, 4 figures, submitted to Physical Review Letter
A CGE model with ICT and R&D-driven endogenous growth: A detailed model description
We present a multi-country, multi-sector dynamic general equilibrium model with ICT and R&D-driven endogenous growth.
The model presented has been developed to study the economic effects of public support to ICT R&D in the European
Union. It accommodates alternative policy instruments that could be used in an attempt to stimulate private ICT R&D
expenditures, including general production grants, tax credit or subsidies targeted at specific inputs. The model is
calibrated to data from four country blocs Germany, France, the Rest of the EU and the Rest of the World.JRC.J.3-Information Societ
A CGE model with ICT and R&D-driven endogenous growth: A general description
This report describes the first release of the macroeconomic model developed under the project Prospective Insights on R&D in ICT (PREDICT 2), a research project co-financed by the Directorate General for Communications Networks, Content and Technology and the JRC-IPTS. One of the objectives of PREDICT 2 is the development of a macroeconomic model which allows the economic analysis of public support to ICT R&D in the European Union.
This report provides a motivation for the chosen modelling approach, describes the model structure and the calibration of the model to a reference growth path.JRC.J.3-Information Societ
Alien Registration- Christensen, Martin (Baldwin, Cumberland County)
https://digitalmaine.com/alien_docs/32935/thumbnail.jp
Formulation and validation of applied engineering equations for heat transfer processes in the food industry
Biology of Dirofilaria immitis (Leidy, 1850) (Nematoda: Onchocercidae) and Aedes trivittatus (Coquillett, 1902) (Diptera: Culicidae) in Central Iowa
"A halting-stage in the evolution of logical theory":John Dewey’s critical engagement with Lotze’s logic
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