Palatini's cousin: A New Variational Principle

A variational principle is suggested within Riemannnian geometry, in which an auxiliary metric and the Levi Civita connection are varied independently. The auxiliary metric plays the role of a Lagrange multiplier and introduces non-minimal coupling of matter to the curvature scalar. The field equations are 2nd order PDEs and easier to handle than those following from the so-called Palatini method. Moreover, in contrast to the latter method. no gradients of the matter variables appear. In cosmological modeling, the physics resulting from the new variational principle will differ from the modeling using the Palatini method.Comment: 12 page

Dollarization and the conquest of hyperinflation in divided societies

This study argues that the delegation of monetary policy control by one country to another can reduce inflation in the delegating country. Hyperinflation is common in a divided society, one in which special interest groups can pressure a weak central government to issue money to finance their own demands while neglecting the country’s overall welfare. A commitment device like dollarization or a currency board, which gives control of the divided country’s money supply to another country, can eliminate this inflation bias. This is illustrated by Argentina’s experience with inflation and a currency board which, in effect, gave control of Argentina’s money supply to the United States. This argument is made precise using a two-country overlapping generations model to study the effects of delegation. The study also finds that a dollarization treaty between the two countries can be welfare-improving for bothDollarization

The multigraded Nijenhuis-Richardson Algebra, its universal property and application

We define two $(n+1)$ graded Lie brackets on spaces of multilinear mappings. The first one is able to recognize $n$-graded associative algebras and their modules and gives immediately the correct differential for Hochschild cohomology. The second one recognizes $n$-graded Lie algebra structures and their modules and gives rise to the notion of Chevalley cohomology

Développer des chaînes de valeur agro-pastorales pluviales à travers les plateformes d’innovation: Expériences avec des communautés rurales dans le Bassin de la Volta

Le Système Multi-acteur comme Plateforme d’Innovation (IP) Le Programme de défi pour l’eau et l’alimentation dans le Bassin de la Volta (CPWF-Volta) vise « à renforcer la gestion intégrée des eaux pluviales et des petits barrages afin qu’elles puissent être exploitées mieux équitablement pour des usages multiples ». L’un des moyens par lequel on peut atteindre cet objectif est d’augmenter la productivité agricole et pastorale par des Stratégies de gestion des eaux pluviales et d’améliorer la productivité de l’eau au niveau champêtre

Recurrence in generic staircases

The straight-line flow on almost every staircase and on almost every square tiled staircase is recurrent. For almost every square tiled staircase the set of periodic orbits is dense in the phase space

Surface properties of ocean fronts

Background information on oceanic fronts is presented and the results of several models which were developed to study the dynamics of oceanic fronts and their effects on various surface properties are described. The details of the four numerical models used in these studies are given in separate appendices which contain all of the physical equations, program documentation and running instructions for the models

Dry Edible Beans: Production and Marketing, Red River Valley

Marketing, Production Economics,

Developing rainfed crop-livestock value chains through Innovation Platforms: experiences with rural communities in the Volta Basin

Multi-actor system as an Innovation Platform (IP) The Challenge Program on Water and Food in the Volta basin aims “to strengthen integrated management of rainwater and small reservoirs so that they can be used equitably for multiple uses.” One way by which to accomplish this is to increase crop and livestock productivity through Rainwater Management Strategies (RMS) and improve water productivity at the farm level

An analysis of the Geneva mechanism as a timing device

A mathematical analysis of the Geneva mechanism was conducted to determine the potential of this device as a tinting mechanism, and the feasibility of replacing the widely used pallet and starwheel escapement with a Geneva mechanism. The primary objective of the study was to determine if the Geneva mechanism will attain a terminal velocity, and if so, how much time is required to reach this velocity. To accomplish this objective, the differential equation of motion for the system was derived using Lagrangian dynatos. The equation was programmed and solved on a digital computer. The study indicated that the Geneva mechanism does reach a terminal velocity, and consequently can be used as a timing device. The mechanism, however, requires as much as fifty milliseconds to attain this terminal velocity