3,426 research outputs found
Investigation of Zero-Modes for a Dynamical D-Brane
In this article, we investigate zero-modes for a dynamical (rotating-moving)
D-brane, coupled to the electromagnetic and tachyonic background fields.
This work is done by the boundary state methods, in three cases of bosonic and
fermionic boundary states and superstring partition function. By analyzing the
obtained zero-modes in either of the cases, interesting results will be
obtained. Our findings demonstrate the importance of the zero-mode and its
effects on the background fields and the defined internal properties of the
described system.Comment: 15 pages, 1 tabl
Sustainability and Optimality in Economic Development: Theoretical Insights and Policy Prospects
This paper takes sustainability to be a matter of intergenerational welfare equality and examines whether an optimal development path can also be sustainable. It argues that the general “zero-net-aggregate-investment” condition for an optimal development path to be sustainable in the sense of the maximin criterion of intergenerational justice is too demanding to be practical, especially in the context of developing countries. The maximin criterion of sustainability may be more appealing to the rich advanced industrial countries, but is too costly and ethically unreasonable for developing nations as it would act as an intergenerational “poverty equalizer”. The paper suggests that a compromise development policy that follows the optimal growth approach but adopts certain measures to mitigate the intergenerational and intragenerational welfare inequalities may better serve these countries. Some of the principal elements of such a policy are highlighted.Sustainability, Intergenerational Equity, Optimality, Discounting, Development Policy
On the Hybrid Minimum Principle On Lie Groups and the Exponential Gradient HMP Algorithm
This paper provides a geometrical derivation of the Hybrid Minimum Principle
(HMP) for autonomous hybrid systems whose state manifolds constitute Lie groups
which are left invariant under the controlled dynamics of the
system, and whose switching manifolds are defined as smooth embedded time
invariant submanifolds of . The analysis is expressed in terms of extremal
(i.e. optimal) trajectories on the cotangent bundle of the state manifold .
The Hybrid Maximum Principle (HMP) algorithm introduced in \cite{Shaikh} is
extended to the so-called Exponential Gradient algorithm. The convergence
analysis for the algorithm is based upon the LaSalle Invariance Principle and
simulation results illustrate their efficacy
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