Graph-based structural analysis of planar mechanisms.

Kinematic structure of planar mechanisms addresses the study of attributes determined exclusively by the joining pattern among the links forming a mechanism. The system group classification is central to the kinematic structure and consists of determining a sequence of kinematically and statically independent-simple chains which represent a modular basis for the kinematics and force analysis of the mechanism. This article presents a novel graph-based algorithm for structural analysis of planar mechanisms with closed-loop kinematic structure which determines a sequence of modules (Assur groups) representing the topology of the mechanism. The computational complexity analysis and proof of correctness of the implemented algorithm are provided. A case study is presented to illustrate the results of the devised method.

Foreign direct investment, exports, gross domestic product and the labor market in Puerto Rico

In this paper, a vector autorregresive model (VAR) is applied to examine the interrelationship among foreign direct investment, exports, Gross Domestic Product (GDP), unemployment rate and labor force participation rate in Puerto Rico, taking into account a time period that includes the fiscal years from 1980 to 2010 -- Four cointegrating vectors were found in the system which indicates that there is a long run relationship between the variables -- The findings suggest that consecutive increases in foreign direct investment inflows could significantly reduce the unemployment rate and increase interest in joining the labor force in Puerto Rico -- The same result also applies to increases in export levels -- The variations in Gross Domestic Product are mainly explained in the long run by the unemployment rate