Search results for "Modular"

A NOTE ON THE CATEGORICAL NOTIONS OF NORMAL SUBOBJECT AND OF EQUIVALENCE CLASS

2021

In a non-pointed category E, a subobject which is normal to an equivalence relation is not necessarily an equivalence class. We elaborate this categorical distinction, with a special attention to the Mal'tsev context. Moreover, we introduce the notion of fibrant equipment, and we use it to establish some conditions ensuring the uniqueness of an equivalence relation to which a given subobject is normal, and to give a description of such a relation.

A note on strong protomodularity, actions and quotients

2013

We investigate some properties of the fibration of points. We obtain a characterization of protomodular categories among pointed regular ones, and, in the semi-abelian case, a characterization of strong protomodularity. Everything is also stated in terms of internal actions.

Transaction Costs, Standardization and Modularity in Credit Risk Transfer Market

2010

The advent of a credit risk market has profoundly altered the role of banking firms into one of asset originator and asset distributor rather than the asset holder. Banks have traditionally originated and held credit risk. It emphasis the different role of financial institutions from holders of credit risk to originators and distributors of credit risk. In this paper I aim to evaluate how the modularity and the standardization create the precondition for the creation of a credit risk transfer market in the banking industry. The intermediate market of credit risk transfer appears when the banking production processes have become more disintegrated. The vertical disintegration of the banking …

Identifying modularity structure of a genetic network in gene expression profile data

2009

Aim of this paper is to define a new statistical framework to identify central modules in Gaussian Graphical Models (GGMs) estimated by gene expression data measured on a sample of patients with negative molecular response to Imatinib. Imanitib is a drug used to treat certain types of cancer that in many statistical studies has been reported to have a significant clinical effect on chronic myeloid leukemia (CML) in chronic phase as well as in blast crisis. For central module in a GGM we intend a module containing genes that are defined differently expressed.

Sistemi frattali in biologia ed in medicina umana.

2009

Modeling lightning observations from space-based platforms (CloudScat.jl 1.0)

2020

This is an open access article. This work is distributed under the Creative Commons Attribution 4.0 License.

Bill2d - a software package for classical two-dimensional Hamiltonian systems

2015

Abstract We present Bill2d , a modern and efficient C++ package for classical simulations of two-dimensional Hamiltonian systems. Bill2d can be used for various billiard and diffusion problems with one or more charged particles with interactions, different external potentials, an external magnetic field, periodic and open boundaries, etc. The software package can also calculate many key quantities in complex systems such as Poincare sections, survival probabilities, and diffusion coefficients. While aiming at a large class of applicable systems, the code also strives for ease-of-use, efficiency, and modularity for the implementation of additional features. The package comes along with a use…

Stackelberg equilibrium with many leaders and followers. The case of zero fixed costs

2017

Abstract I study a version of the Stackelberg game with many identical firms in which leaders and followers use a continuous cost function with no fixed cost. Using lattice theoretical methods I provide a set of conditions that guarantee that the game has an equilibrium in pure strategies. With convex costs the model shows the same properties as a quasi-competitive Cournot model. The same happens with concave costs, but only when the number of followers is small. When this number is large the leaders preempt entry. I study the comparative statics and the limit behavior of the equilibrium and I show how the main determinants of market structure interact. More competition between the leaders …

Modular Structures on Trace Class Operators and Applications to Landau Levels

2009

The energy levels, generally known as the Landau levels, which characterize the motion of an electron in a constant magnetic field, are those of the one-dimensional harmonic oscillator, with each level being infinitely degenerate. We show in this paper how the associated von Neumann algebra of observables displays a modular structure in the sense of the Tomita–Takesaki theory, with the algebra and its commutant referring to the two orientations of the magnetic field. A Kubo–Martin–Schwinger state can be built which, in fact, is the Gibbs state for an ensemble of harmonic oscillators. Mathematically, the modular structure is shown to arise as the natural modular structure associated with the…

Splitting the dynamics of large biochemical interaction networks

2003

This article is inscribed in the general motivation of understanding the dynamics on biochemical networks including metabolic and genetic interactions. Our approach is continuous modeling by differential equations. We address the problem of the huge size of those systems. We present a mathematical tool for reducing the size of the model, master-slave synchronization, and fit it to the biochemical context.