Política econômica e credibilidade: evidências empíricas e técnicas econométricas [Economic policy and credibility: empirical evidence and econometric techniques]

This article presents a review of empirical literature regarding the credibility of economic policy, dedicating special attention to the econometric techniques used. The literature researched is comprised of two groups based on the type of econometric technique employed. However, within the main groups, reference is made to the four ways of conducting monetary policy currently being used in the world today: monetary aggregate targets, exchange rate peg, inflation targets, and preventive monetary policy with no explicit nominal peg. This text also refers to underlying theoretical models, when applicable. Brazilian empirical literature on this subject is reviewed in its own separate section.credibility, monetary policy, econometric models

La importancia del derecho en la lucha contra el cambio climático

[ES] En un contexto de lucha contra el cambio climático el derecho juega un papel importante. Se ha explicado la importancia que tienen los tratados internacionales, las diferentes leyes climáticas y los litigios climáticos como herramientas muy influyentes en la lucha que tiene el ser humano contra el cambio climático. Dentro de cada explicación se han analizados detalladamente las diferentes herramientas.[EUS] Klima-aldaketaren aurkako borrokan, zuzenbideak zeregin garrantzitsua du. Nazioarteko itunek, klima-legeek eta klima-auziek duten garrantzia azaldu da, gizakiak klima-aldaketaren aurka duen borrokan eragin handia duten tresnak baitira. Azalpen bakoitzaren barruan, tresnak zehatz-mehatz aztertu dira.[EN] In the context of combating climate change, law plays an important role. The importance of international treaties, different climate laws and climate litigation as very influential tools in the human fight against climate change has been explained. Within each explanation, the different tools have been analyzed in detail

Normalization factors for magnetic relaxation of small particle systems in non-zero magnetic field

We critically discuss relaxation experiments in magnetic systems that can be characterized in terms of an energy barrier distribution, showing that proper normalization of the relaxation data is needed whenever curves corresponding to different temperatures are to be compared. We show how these normalization factors can be obtained from experimental data by using the $T \ln(t/\tau_0)$ scaling method without making any assumptions about the nature of the energy barrier distribution. The validity of the procedure is tested using a ferrofluid of Fe_3O_4 particles.Comment: 5 pages, 6 eps figures added in April 22, to be published in Phys. Rev. B 55 (1 April 1997

Caracterización de la planeación y el control de la producción en las mipymes del sector manufacturero en la ciudad Neiva

El estudio realizado en las Mipymes de Neiva para la caracterización de la Planificación y el control de la producción, los cuales se constituyen en pilar fundamental para alcanzar los niveles de competitividad regional se basó en los estudios de tiempos y movimientos, capacidad de producción, eficiencia de cada centro de producción y del total de la planta, nivel de utilización de cada centro, y del total de la planta, registros de ventas de los últimos cinco años y la técnica del pronóstico para encontrar el tamaño de las ventas a futuro. Para la planeación a corto plazo se estudiaron los siguientes aspectos: Plan Maestro de Producción, evaluación de los diferentes planes, capacidad necesaria de cada lote de producción, diagramas de ruta para sus productos, registros de carga de cada operación, lista de materiales para cada producto, registro para identificar cuando pedir y registro de inventarios. El estudio arroja como resultado que las pequeñas empresas y las microempresas, carecen de sistemas de planeación y control y que los registros históricos necesarios para adelantar dichas labores son incipientes, con baja utilización de mano de obra calificada y poca intervención de profesionales en los procesos de gestión empresarial

A CREDIBILIDADE DA POLÍTICA ECONÔMICA: UMA REVISÃO CRÍTICA DA TEORIA

O objetivo deste artigo é fazer uma revisão crítica da literatura teórica sobre a credibilidade da política econômica. Para tanto, além da introdução, o artigo divide-se em três partes: na primeira, analisa-se por que o problema da credibilidade é importante para a economia e para os policymakers; na segunda, avaliam-se as formas de se enfrentar ou resolver este problema; por último, na terceira, apresentam-se as conclusões.This paper presents a critical survey of the theoretical literature on credibility aspects of economic policy. We discuss why is credibility important for economic policy and mostly how can one solve the time inconsistency problem of the optimal economic policy

Field induced magnetic transition and metastability in Co substituted Mn2SbMn_{2}Sb

A detailed investigation of first order ferrimagnetic (FRI) to antiferromagnetic (AFM) transition in Co (15%) doped $Mn_2Sb$ is carried out. These measurements demonstrate anomalous thermomagnetic irreversibility and glass-like frozen FRI phase at low temperatures. The irreversibility arising between the supercooling and superheating spinodals is distinguised in an ingenious way from the irreversibility arising due to kinetic arrest. Field annealing measurements shows reentrant FRI-AFM-FRI transition with increasing temperature. These measurements also show that kinetic arrest band and supercooling band are anitcorrelated i.e regions which are kinetically arrested at higher temperature have lower supercooling temperature and vice versa.Comment: 10 pages, 8 figure

Macroscopic Quantum Tunneling of a Domain Wall in a Ferromagnetic Metal

The macroscopic quantum tunneling of a planar domain wall in a ferromagnetic metal is studied based on the Hubbard model. It is found that the ohmic dissipation is present even at zero temperature due to the gapless Stoner excitation, which is the crucial difference from the case of the insulating magnet. The dissipative effect is calculated as a function of width of the wall and is shown to be effective in a thin wall and in a weak ferromagnet. The results are discussed in the light of recent experiments on ferromagnets with strong anisotropy. PACS numbers:75.60.Ch, 03.65.Sq, 75.10.LpComment: 13page

Tunneling of a Quantized Vortex: Roles of Pinning and Dissipation

We have performed a theoretical study of the effects of pinning potential and dissipation on vortex tunneling in superconductors. Analytical results are obtained in various limits relevant to experiment. In general we have found that pinning and dissipation tend to suppress the effect of the vortex velocity dependent part of the Magnus force on vortex tunneling.Comment: Latex, 12 page