1,633 research outputs found
SOM-based Data Analysis of Speculative Attacks' Real Effects
In some cases, currency crises are followed by strong recessions (e.g., recent Asian and Argentinean crises), but in other cases they are not. This paper uses Self-Organizing Maps (SOM) to search for meaningful associations between speculative attacks' real effects and 28 variables that characterize the economic, financial, legal, and socio-political structure of the country at the onset of the attack. SOM is a neural network-based generalization of Principal Component Analysis (PCA) that provides an efficient non-linear projection of the multidimensional data space on a curved surface. This paper finds a strong association of speculative attacks' real effects with fundamentals and the banking sector structureexploratory data analysis, self-organizing maps, neural networks, speculative attacks' real effects
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An organizational analysis of the community legal education movement in the legal services corporation.
This study examines how teaching about the law complements the work of legal services programs for the poor, how Community Legal Education (CLE) has been designed and implemented, what problems have programs faced implementing CLE, and what solutions have been proposed to overcome those problems. This study traces the historical foundations and development of CLE within the Legal Services Corporation (LSC). It also examines organizational characteristics of 62 legal services programs with identifiable CLE components and describes how three programs have successfully integrated CLE into their work. Finally, it sets forth a series of recommendations for the LSC and local programs to research and develop CLE as a complementary service component. This study indicates that CLE is not well understood by many persons employed in legal services and that such misunderstanding may be attributed to the plurality of CLE functions. The study also found that CLE functions include eradicating legal illiteracy, providing alternatives to individual case aid, acting as a complementary strategy to law reform work, insuring that the program remains accountable to clients, and promoting client involvement to insure the program\u27s political survival. This study reveals that while CLE was one of the original service modalities for legal services programs, it has not been considered important enough to develop on a large scale. Four major obstacles to the implementation of CLE have been identified: (a) inadequate criteria to test CLE effectiveness, (b) LSC dependence on clients for political protection, (c) reliance on attorneys to design and implement CLE, and (d) the limitations inherent in assisting large numbers of clients on an individual basis. The study concludes that CLE can be an effective service if integrated into the LSC structure and made a part of other LSC activities
Optimal control of fed-batch processes with particle swarm optimization
Optimal control problems appear in several engineering fields. These problems are often described by sets of nonlinear differential and algebraic equations, usually subject to constraints in the state and control variables. Some bioprocess optimal control problems are revisited and a numerical approach to its solution is introduced.
The numerical procedure used to solve the problems takes advantage of the well know modeling AMPL language, providing an external dynamic library that solve the nonlinear differential equations. The optimal control problem as generally presented belongs to the class of semi-infinite programming (SIP) problems. A transformation of the SIP problem results in a nonlinear optimization problem (NLP) that can be address by off-the-shelf optimization software. The NLP formulation results in nondifferentiable optimization problems were the global solution is mostly desirable. We apply a particle swarm optimization strategy implemented in the MLOCPSOA [13] solver. Particle swarm optimization (PSO) is a stochastic technique that mimics the social behavior of a swarm
An application of semi-infinite programming to air pollution control
Environment issues are more then ever important in a modern society.
Complying with stricter legal thresholds on pollution emissions raises an important economic issue. This talk presents some ideas in the use of optimization tools to help in the planning and control of non mobile pollution sources.
We assume a Gaussian plume model where a plume rise and weather stabilities classes are considered.
Three main semi-infinite programming formulations are described and numerical results are shown
Optimização e controlo da poluição atmosférica
Alguns problemas de controlo da poluição atmosférica podem ser formulados
como problemas de programação semi-infinita (PSI). Estas formulações, das quais
descrevemos três abordagens, permitem que as instalações fabris cumpram a legislação da poluição atmosférica enquanto que o impacto económico é minimizado. As mesmas ferramentas da programação matemática podem também ser usadas pelas autoridades competentes no sentido de verificar que os limites impostos por lei são cumpridos, através do planeamento da localização dos postos de amostragem/controlo. A primeira das formulações consiste em optimizar um
determinado objectivo enquanto que o nível de poluição atmosférica é mantido
abaixo de um valor de referência. A segunda consiste no cálculo da poluição
atmosférica máxima atingida numa determinada região e a terceira considera um
problemas de redução da poluição. Estas formulações permitem obter os melhores
parâmetros de controlo e as posições onde os valores máximos da poluição são
atingidos, posições essas que correspondem ao melhor posicionamento dos postos
de amostragem/controlo.
As abordagens propostas são ilustradas com quatro problemas académicos. As ferramentas actualmente existentes apoiam a PSI desde a modelação do problema até à sua resolução. A linguagem de modelação (SIP)AMPL foi usada para codificar os problemas propostos e o solver NSIPS foi empregue na resolução dos mesmos
Semi-infinite air pollution control problems
Semi-infinite programming (SIP) problems arise in many engineering areas. Robot trajectory
planning and optimal signal sets are two fine examples. Air pollution abatement problems, which
are linear SIP problems, were proposed in the seventies by Gustafson and Kortanek [Analytical
properties of some multiple-source urban diffusion models, Environment and Planning 4, pp. 31-
41, 1972].
Recent available tools for non-linear SIP allow the formulation of more general air control
problems, namely the optimum stack design.
In the air control SIP problem an objective function is to be optimised (minimum stack height or
minimum cleaning costs), where the air pollution, at ground level, is kept bellow a given
threshold. A Gaussian model is used to provide estimates of air pollution in a region where mean
weather conditions are assumed.
In this talk, we present three formulated air pollution control problems coded in the (SIP)AMPL
modelling language and numerical results obtained with the discretization method of the NSIPS
solver
Texture of Two Vanishing Subtraces in Neutrino Mass Matrix and Current Experimental Tests
We present a full phenomenological and analytical study for the neutrino mass
matrix characterized by two vanishing subtraces. We update one past
result in light of the recent experimental data. Out of the fifteen possible
textures, we find seven cases can accommodate the experimental data instead of
eight ones in the past study. We also introduce few symmetry realizations for
viable and nonviable textures based on non-abelian ( or ) flavor
symmetry within type II seesaw scenario.Comment: pdflatex, 57 pages, 10 tables, 9 figures, version to appear in PR
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