Hamiltonian mechanics on discrete manifolds

The mathematical/geometric structure of discrete models of systems, whether these models are obtained after discretization of a smooth system or as a direct result of modeling at the discrete level, have not been studied much. Mostly one is concerned regarding the nature of the solutions, but not much has been done regarding the structure of these discrete models. In this paper we provide a framework for the study of discrete models, speci?cally we present a Hamiltonian point of view. To this end we introduce the concept of a discrete calculus

Blade loss transient dynamics analysis. Volume 3: User's manual for TETRA program

The users manual for TETRA contains program logic, flow charts, error messages, input sheets, modeling instructions, option descriptions, input variable descriptions, and demonstration problems. The process of obtaining a NASTRAN 17.5 generated modal input file for TETRA is also described with a worked sample

Classical Tensors and Quantum Entanglement I: Pure States

The geometrical description of a Hilbert space asociated with a quantum system considers a Hermitian tensor to describe the scalar inner product of vectors which are now described by vector fields. The real part of this tensor represents a flat Riemannian metric tensor while the imaginary part represents a symplectic two-form. The immersion of classical manifolds in the complex projective space associated with the Hilbert space allows to pull-back tensor fields related to previous ones, via the immersion map. This makes available, on these selected manifolds of states, methods of usual Riemannian and symplectic geometry. Here we consider these pulled-back tensor fields when the immersed submanifold contains separable states or entangled states. Geometrical tensors are shown to encode some properties of these states. These results are not unrelated with criteria already available in the literature. We explicitly deal with some of these relations.Comment: 16 pages, 1 figure, to appear in Int. J. Geom. Meth. Mod. Phy

Blade loss transient dynamics analysis, volume 1. Task 1: Survey and perspective

An analytical technique was developed to predict the behavior of a rotor system subjected to sudden unbalance. The technique is implemented in the Turbine Engine Transient Rotor Analysis (TETRA) computer program using the component element method. The analysis was particularly aimed toward blade-loss phenomena in gas turbine engines. A dual-rotor, casing, and pylon structure can be modeled by the computer program. Blade tip rubs, Coriolis forces, and mechanical clearances are included. The analytical system was verified by modeling and simulating actual test conditions for a rig test as well as a full-engine, blade-release demonstration

Inditex succes, Hennes and Maurtiz's shade and their strategic management.

Different strategies adopted by corporation’s management condition its market success. If a strategy were good enough, the rest of the corporations that operate on its activity segment which have similar characteristics would try to copy it. Inditex is leading the textile sector, meanwhile Hennes and Mauritz (H&M) is not getting closer enough to Inditex in order to obtain a vantage point forehead to it. This article is a comparative analysis about the policy, the strategy and the result of them.Inditex; Hennes and Mauritz; Dirección Estratégica; Inversión Internacional; Información Segmentada

The decision-making process in offshoring and international investment.

This paper is made up of two sections. First one which analyzed some of the variables that are part of decision-making process in offshoring: direct foreign investment, exchange rate, production cost and exports. Costs associated to offshoring operations are analyzed on the second section. On this section, two countries by geographical area have been chosen. The choice has been made in light of what have been the best results on the first section.Deslocalización; Inversión Internacional; Mercados Emergentes; Inversión Directa Extranjera; Tasa Cambiaria; Coste de Producción.

Political Competition and Policy Adoption: Market Reforms in Latin American Public Utilities

This paper shows that political competition generates incentives that affect the pace of adoption of market reforms in the context of policy convergence. Previous work shows the effect of financial and technological pressures in promoting policy convergence and the impact of institutional constraints on shaping the pace of policymaking. Controlling for these effects, this paper demonstrates the policy effects of political competition and ideological polarization between the incumbent and its contenders even at a time when ideological policy differences seem to be fading due to policy convergence. In studying policy adoption, the authors use duration analysis for the 18 countries of Latin America during the 1985-2000 period when most of the market reforms in public utilities were adopted

Filamentous bacteria inhabiting the sheaths of marine Thioploca spp. on the Chilean continental shelf

A new component of the benthic Thioploca mat microbial ecosystem on the Chilean continental shelf was detected by epifluorescence microscopy: filamentous, bacterial endobionts of 4–5-μm filament diameter and length sometimes exceeding 1 mm. These filaments were identified as growing within Thioploca sheaths located between the sediment surface and c. 5 cm depth. Their location coincided with maximal biomass and biovolume of Thioploca filaments in surficial sediments, and with maximal abundance and activity of sulfate-reducing bacterial populations near the sediment/water interface. FISH and environmental characteristics support the working hypothesis that these endobiont populations are members of the filamentous, sulfate-reducing bacterial genus Desulfonema. Found at several sampling stations over a decade-long interval (1994–2006), these populations appear to be a stable component of the Chilean Thioploca mat ecosystem

Magnetization in AIIIBV semiconductor heterostructures with the depletion layer of manganese

The magnetic moment and magnetization in GaAs/Ga$_{0.84}$In$_{0.16}$As/GaAs heterostructures with Mn deluted in GaAs cover layers and with atomically controlled Mn $\delta$-layer thicknesses near GaInAs-quantum well ($\sim$3 nm) in temperature range T=(1.8-300)K in magnetic field up to 50 kOe have been investigated. The mass magnetization all of the samples of GaAs/Ga$_{0.84}$In$_{0.16}$As/GaAs with Mn increases with the increasing of the magnetic field that pointed out on the presence of low-dimensional ferromagnetism in the manganese depletion layer of GaAs based structures. It has been estimated the manganese content threshold at which the ferromagnetic ordering was found.Comment: 8 pages, 3 figure