Ontology of multi-agents processes of spatial decision

In the paper of Cavezzali, Girotti and Rabino presented at ERSA 2003 conference, features of multi-agent models and their potentiality for the study of territorial phenomena are discussed. Starting from this study, the present paper digs deeper mechanisms of multi-agent systems working, describing their ontology in a more complete and articulated way as possible, and investigating: the properties of the actors, the mechanisms of interaction among actors and between actors and environment. About the environment, particular attention has been paid to the consideration about the various modalities of treatment of territory (from pure physical support to active reactive/cognitive agent in relationship with the other agents). For these modalities, finally, two typical case-studies of multi-agent model are shown: simulation of pedestrian paths choice, the software “Turisti”, and a competitive dynamic of service centres location, “Wilson”.

Multi-Agents Systems and Territory: Concepts, Methods and Applications

This paper analyses the multi-agents systems that are now considered the best tool to simulate and study real world. We review the main characteristics of a multi-agents system, namely interactions and cooperations of agents, communications and behaviours between them and finally the schedule of actions and jobs assignment to agents. The multi-agents system approach is increasingly applied in social and economic sciences; so we study mainly the territorial applications. In these applications new characteristics arise from the consideration of territory (land and space where the agents live or territory as an agent in itself, that evolves in the time). We study possible new applications of multi-agents applied to the territory (for instance, to define town planning policies or to locate dangerous facilities). Furthermore we study new tools to make operational multi-agents systems (mainly Swarm, the toolkit of Santa Fe Institute). With Swarm we present two kind of territorial applications: with located agents (fixed in space) and with not located agents (moving in the space). Finally we show the results of these applications.

Multi-Agents Systems and Territory: Concepts, Methods and Applications

This paper analyses the multi-agents systems that are now considered the best tool to simulate and study real world. We review the main characteristics of a multi-agents system, namely interactions and cooperations of agents, communications and behaviours between them and finally the schedule of actions and jobs assignment to agents. The multi-agents system approach is increasingly applied in social and economic sciences; so we study mainly the territorial applications. In these applications new characteristics arise from the consideration of territory (land and space where the agents live or territory as an agent in itself, that evolves in the time). We study possible new applications of multi-agents applied to the territory (for instance, to define town planning policies or to locate dangerous facilities). Furthermore we study new tools to make operational multi-agents systems (mainly Swarm, the toolkit of Santa Fe Institute). With Swarm we present two kind of territorial applications: with located agents (fixed in space) and with not located agents (moving in the space). Finally we show the results of these applications

Aplicación de leyes fundamentales de la densidad a bosques de Nothofagus: I. Regla de los -3/2 o ley del autorraleo = Applicability of density rules on Nothofagus forests: I. The -3/ 2 power law or self-thinning

Con el fin de interpretar la dinámica de los bosques de Nothofagus de Norpatagonia-Argentina, se han estudiado los comportamientos de algunas leyes fundamentales relacionadas con la densidad y mortalidad de los rodales. En este artículo se expondrán los resultados obtenidos al aplicar dos expresiones relacionadas con la ley de los -3/2 o del autorraleo a los bosques puros y mixtos de Nothofagus. Del conjunto de expresiones relacionadas con esta ley se decidió trabajar más profundamente con la relación potencial entre el número de árboles y el diámetro promedio del rodal (Reineke 1933). Se emplearon datos provenientes de parcelas temporales y permanentes. La función se ajustó por dos procedimientos: regresión y gráfico o manual, que se estudiaron para diferentes tipos forestales. Se diferenciaron dos tendencias máximas lineales de la relación tamaño-densidad, la primera hasta un diámetro de 30 cm, y la segunda por encima de este último. Los dos métodos de ajuste dieron pendientes predominantemente superiores a la universal (-1.605), siendo los rodales con presencia de N. nervosa, los que presentaron la línea de densidad máxima más baja. Se logró caracterizar el comportamiento de la ley en los bosques de Nothofagus y se definió la expresión del índice de Densidad Relativa para los mismos.To understand the dynamic of Nothofagus forests in Argentina's Northern Patagonia, the behaviour of some fundamental biological laws related to stand density and mortality were studied. This paper presents the results of applying the law of -3/2 or self-thinning rule to pure and mixed stands of Nothofagus species. Although there are many equations related to this law, it was decided to mainly work with the potential relationship between number of trees and the mean diameter of the stand (Reineke 1933). Also, the mean volume and number of trees relationship was examined. Data from temporal and permanent sample plots were used. For the different forest types, different equation adjustments were made with two different methods: regression and graphical analysis. Two maximum linear trends for size-density relationship were obtained: the fisrt one up to a diameter of 30 cm and the second one over this size. The equations adjustment by means of two methods resulted in a steeper slope than the universal -1,605. The stands containing N. nervosa displayed the lowest maximum density line. The behaviour of the law was characterised. Also, the Relative Density Index for Nothofagus forests was determined.EEA BarilocheFil: Chauchard, Luis Mario. Universidad Nacional del Comahue. Asentamiento Universitario San Martín de los Andes; ArgentinaFil: Chauchard, Luis Mario. Administración de Parques Nacionales. Delegación Regional Patagonia; ArgentinaFil: Chauchard, Luis Mario. Instituto Nacional de Tecnología Agropecuaria. Estación Experimental Agropecuaria Bariloche; ArgentinaFil: Sbrancia, Renato. Universidad Nacional del Comahue. Asentamiento Universitario San Martín de los Andes; ArgentinaFil: Sbrancia, Renato. Administración de Parques Nacionales. Delegación Regional Patagonia; ArgentinaFil: Sbrancia, Renato. Instituto Nacional de Tecnología Agropecuaria. Estación Experimental Agropecuaria Bariloche; ArgentinaFil: Gonzalez, Marcelo Raul. Universidad Nacional del Comahue. Asentamiento Universitario San Martín de los Andes; ArgentinaFil: Gonzalez, Marcelo Raul. Administración de Parques Nacionales. Delegación Regional Patagonia; ArgentinaFil: Gonzalez, Marcelo Raul. Instituto Nacional de Tecnología Agropecuaria. Estación Experimental Agropecuaria Bariloche; ArgentinaFil: Maresca, Leonardo. Universidad Nacional del Comahue. Asentamiento Universitario San Martín de los Andes; ArgentinaFil: Maresca, Leonardo. Administración de Parques Nacionales. Delegación Regional Patagonia; ArgentinaFil: Maresca, Leonardo. Instituto Nacional de Tecnología Agropecuaria. Estación Experimental Agropecuaria Bariloche; ArgentinaFil: Rabino, Alberto. Universidad Nacional del Comahue. Asentamiento Universitario San Martín de los Andes; ArgentinaFil: Rabino, Alberto. Administración de Parques Nacionales. Delegación Regional Patagonia; ArgentinaFil: Rabino, Alberto. Instituto Nacional de Tecnología Agropecuaria. Estación Experimental Agropecuaria Bariloche; Argentin

Modelos de crecimiento diamétrico para Nothofagus dombeyi = Diameter growth models for Nothofagus dombeyi

Se desarrollaron varios modelos de crecimiento diamétrico para la especie Nothofagus dombeyi. La función seleccionada para el estudio es no lineal, usualmente denominada Bertalanffy-Richards. La misma se ajustó a partir de tres fuentes de datos: parcelas permanentes, análisis fustales y tarugos de incremento. Estos datos fueron segregados por estrato social y luego para cada uno se ajustó la citada función con las variables incremento diamétrico (id)- diámetro a la altura del pecho (dap). Los ajustes y análisis se realizaron a partir de dos grupos de datos. Por un lado se utilizaron datos independientes que provenían principalmente de las parcelas permanentes, mientras que por otro se emplearon series temporales dadas por los tarugos y los análisis fustales. Con ambos grupos se obtuvieron modelos con aplicaciones diferentes. Con el grupo de datos independientes se obtuvieron modelos de interés para la predicción del incremento diamétrico en el corto plazo, mientras que con las series de crecimiento se lograron modelos de una alta significancia biológica. A través de estos modelos biológicos se interpretó la dinámica de crecimiento de las especies estudiadas bajo diferentes situaciones de competencia.Models of diameter growth for Nothofagus dombeyi were developed and the selected model used for this study was non-linear and known as Bertalanffy-Richards. It was fitted from three main data sources: permanent plots (with only two measurements each), stem analysis and tree cores. The data was divided into social strata and then, for each stratum, the model was fitted according to the variables: diameter annual increment (id) and diameter at breast height (dap). The fitting, and both biological and statistical analysis, was carried out taking two different data sets into account: an independent data set, provided by permanent sample plots; and a growth series, provided by tree increment cores and stem analysis. Models with different uses were obtained through both data sets. With the independent data, we obtained models that allowed us to predict the diameter annual increment in a short time and, with the growth series, we obtained models of a high biological significance. In this sense, the biological significance of the parameters from each model was discussed when they were fitted. An interpretation of the dynamic growth of the species studied has been undertaken through the biological models under different competence status.EEA BarilocheFil: Chauchard, Luis Mario. Universidad Nacional del Comahue; ArgentinaFil: Chauchard, Luis Mario. Administración de Parques Nacionales; ArgentinaFil: Chauchard, Luis Mario. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche; ArgentinaFil: Sbrancia, Renato. Universidad Nacional del Comahue; ArgentinaFil: Sbrancia, Renato. Administración de Parques Nacionales; ArgentinaFil: Sbrancia, Renato. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche; ArgentinaFil: Rabino, Alberto. Universidad Nacional del Comahue; ArgentinaFil: Rabino, Alberto. Administración de Parques Nacionales; ArgentinaFil: Rabino, Alberto. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche; ArgentinaFil: Gonzalez Peñalba, Carlos Marcelo. Universidad Nacional del Comahue; ArgentinaFil: Gonzalez Peñalba, Carlos Marcelo. Administración de Parques Nacionales; ArgentinaFil: Gonzalez Peñalba, Carlos Marcelo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche; ArgentinaFil: Maresca, Leonardo. Universidad Nacional del Comahue; ArgentinaFil: Maresca, Leonardo. Administración de Parques Nacionales; ArgentinaFil: Maresca, Leonardo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche; Argentin