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In this paper we present a methodology for ontology design and construction which incorporates the most outstanding design principles and a thorough evaluation process. An ontology provides logical formulation of complex problems of decision sciences like risk management, decision making under uncertainty, statistics and forecasting, negotiation and financial analysis. The main stages of this methodology are: requirements specification, formal design, construction, and evaluation. At each stage of the methodology a series of tasks are defined together with methods and techniques to build the ontology considering quality characteristics. Description logics is used as the formal language during design, a set of informal competency questions is used to support ontology conceptualization; at the evaluation stage, the set of questions are translated to a formal reasoning language and are used for evaluation purposes. Many methodologies and tools have been reported in literature, but little attention has been paid in the creation of consistent, modular, coherent, usable and reusable ontologies as an objective from the beginning of the design process. A comparative analysis with other methodologies is discussed and an Ontological Model for Medical Diagnosis is presented.

Electrochemical cells with a rotating disc electrode are the preferred devices to characterize electrochemical reactions because simple analytical expressions can be used to interpret the information obtained from physical experiments. These equations assume that the velocity field in the vicinity of the electrode active face is in accordance with the ideal behavior described by von Kármán. Experimental liquid velocity measurements inside the cell reported in recent works suggest that the actual liquid flow pattern is not fully in accordance with the assumed ideal behavior. In this work, the Computational Fluid Dynamics technique was employed to characterize numerically the flow pattern inside the electrochemical cell. By using a three-dimensional model, symmetric conditions were not imposed. A biphasic system was employed to evaluate the influence of liquid free surface over the flow pattern. Unsteady state numerical simulations were performed using the commercial software Fluent. Multiple electrode rotation speeds and several cell sizes were employed. Contrary to the assumed behavior, it was obtained that the flow pattern inside the electrochemical cell is not symmetric due to the synergetic effect of the cell walls, the submerged electrode side wall and the liquid free surface. This work states that the differences between actual and the ideal flow patterns can be minimized with plain electrode and cell geometrical modifications.

The financialized growth rate that settled in most developed economies in the nineties is characterized by the quest for higher shareholders’ profitability, increased financial accumulation at the expense of productive accumulation and the use of leverage effects. Stock Flow Consistent models à la Godley and Lavoie are well suited to analyze this growth regime. We retain two types of closures for non financial companies, either an indebtedness norm or an own funds norm. The paper studies the dynamics of these two models with the aid of simulations and supply or demand shocks, or stemming from the financial sector. Their fitness to take into account financial cycles and over indebtedness typical of financialized growth may thus be analyzed. The model with the indebtedness norm generates short-term financial cycles which appear as the regulation mode of this growth regime with an asset price serving as an adjustment variable. The model with the own funds norm generates a financial bubble with growing indebtedness and no self-stabilizing mechanism.