Modeling Sensor Knowledge of a National Hydrologic Information System

In this paper we describe our experience in modeling and using sensor knowledge of a national hydrologic information system in Spain. We developed a web application called VSAIH supported by a knowledge-based system to analyze sensor data and to generate explanations that help users to make decisions based on hydrologic behavior. In the paper, we describe the characteristics of the infrastructure of hydrologic sensors and the representa-tion we used to model sensor knowledge to provide support to the VSAIH application. We also describe semi-automatic procedures that we applied to construct the final model

Reusable Knowledge-based Components for Building Software Applications: A Knowledge Modelling Approach

In computer science, different types of reusable components for building software applications were proposed as a direct consequence of the emergence of new software programming paradigms. The success of these components for building applications depends on factors such as the flexibility in their combination or the facility for their selection in centralised or distributed environments such as internet. In this article, we propose a general type of reusable component, called primitive of representation, inspired by a knowledge-based approach that can promote reusability. The proposal can be understood as a generalisation of existing partial solutions that is applicable to both software and knowledge engineering for the development of hybrid applications that integrate conventional and knowledge based techniques. The article presents the structure and use of the component and describes our recent experience in the development of real-world applications based on this approach

Present day Nd isotopic composition of seawater and sediment leaches from the Pacific sector of the Southern Ocean

ABSTRACT FINAL ID: PP11B-1785 The Southern Ocean plays a key role in the climate evolution of Earth’s history, nevertheless its biggest region, the Pacific sector, has been poorly investigated in comparison to other regions in many paleoceanographic aspects. Some of them will try to be explained by the SOPATRA Project (SOuth PAcific TRAnsects). One of those aspects is radiogenic isotope compositions. Hereby we present the first εNd data extracted from Fe-Mn hydroxide coatings of bulk sediments from the Pacific sector of the Southern Ocean. These surface sediments results, scattered along a longitudinal transect of about 10,000 miles, collected from cruise SO213 from middle Chile to New Zealand (between 36°S and 45°S), represent a reliable overview of the present day Nd isotopic composition of the ambient water masses in this region, and will provide useful information for the interpretation of later downcore studies of this water mass tracer. Multiple analysis were carried out to confirm the reliability of the data as well as the validity of the applied leaching method: 1) Measurements of the present day radiogenic Nd bottom water signatures were compared to the Nd isotope compositions of the leachates in order to verify their seawater origin. 2) The leachates’ 87Sr/86Sr isotope ratios were monitored to confirm the holocenic origin of the samples. 3) Radiogenic Nd and Sr compositions of the detrital fraction of the sediment were measured after total dissolution of the same set of samples in order to exclude detrital contamination of leachates. 4) Two different leaching procedures were tested. Preliminary results show εNd values between -4 and -6, corresponding the lowest values to central south Pacific, which could represent the imprint of the circumpolar deep water moving northward. These findings are in agreement with other authors who extracted bottom water Nd isotope compositions from manganese nodules

Career Concerns of Top Executives, Managerial Ownership and CEO Succession

We model the portfolio decisions by managers with career concerns in a context where ownership of the firm's stock can affect the outcome of promotion contests. In addition to their utility from wealth, such managers derive utility from the monetary and non-monetary benefits (prestige) of running a corporation. Our theory predicts that top managers competing for the CEO position will distort their investment decisions away from the optimum portfolio choice in the absence of career concerns. Thus, our model suggests that changing career opportunities can explain portfolio decisions by managers and that insider ownership can help explain the outcomes of promotion contests. Our main testable predictions are that higher ownership by insiders increases their chances of being appointed CEO; that lower ownership by inside managers makes outside CEO appointments more likely; and that a lower probability of CEO turnover (and thus reduced promotion opportunities) leads inside managers to reduce their ownership in the firm and/or to leave the company. Using data on managerial ownership surrounding CEO turnover events, we find evidence supporting the predictions of our model. Overall, our main insight is that insider ownership, the outcome of promotion contests, the choice between inside and outside CEO replacements, and executive departure decisions are all related. Nous développons un modèle de choix de portefeuille des gestionnaires dans un environnement où leurs chances d'être promu PDG sont liées à leur actionnariat dans l'entreprise. Puisque les gestionnaires valorisent leur nomination potentielle au rang de PDG, nous prédisons que leur choix de portefeuille sera biaisé par rapport au choix qu'ils auraient fait en l'absence d'anticipations carriéristes. Notre modèle prédit que des changements dans les chances d'être promu expliquent les choix de portefeuille des gestionnaires. En particulier, nous montrons empiriquement qu'un plus grand actionnariat augmente la chance d'être promu au rang de PDG, réduit la chance qu'un gestionnaire externe à l'entreprise soit nommé. De plus, une réduction dans la possibilité d'être promu réduit l'actionnariat des gestionnaires ou induit leur départ. Nous testons les hypothèses découlant du modèle en utilisant les changements dans l'actionnariat des gestionnaire lors de la démission du PDG. Les hypothèses importantes du modèle sont confirmées.managerial compensation, CEO succession, corporate tournament, portfolio allocation, rémunération des dirigeants, changement de PDG, tournoi corporatif, choix de portefeuille

The socle of a Leavitt path algebra

In this paper we characterize the minimal left ideals of a Leavitt path algebra as those ones which are isomorphic to principal left ideals generated by line point vertices, that is, by vertices whose trees do not contain neither bifurcations nor closed paths. Moreover, we show that the socle of a Leavitt path algebra is the two-sided ideal generated by these line point vertices. This characterization allows us to compute the socle of some algebras that arise as the Leavitt path algebra of some row-finite graphs. A complete description of the socle of a Leavitt path algebra is given: it is a locally matricial algebra.Comment: 13 pg

El sitio de los dólmenes de Antequera en la obra de Georg y Vera Leisner: una revisión

The Antequera dolmens site (Malaga, Spain), included in the UNESCO World Heritage List since July 2016, has a research history of almost 200 years that goes back to the work of Rafael Mitjana y Ardison in the 1840s. After the discovery of the Viera dolmen and El Romeral tholos, in 1903 and 1904 respectively, the research of the great megalithic site received a renewed impulse. Published in 1943, the first volume of the corpus of Iberian megalithic monuments by Georg and Vera Leisner (Die Megalithgräber der Iberischen Halbinsel, Erster Teil: Der Süden) was to become the most detailed study of the Antequera site during the second half of the 20th century, despite the fact that being published in German limited its penetration among the Spanish scholarship. Here, we review the importance of the work of the Leisners to understand the Antequera megaliths in light of the results of the research that has been undertaken in the last 15 years. Many of the issues raised by the German couple continue to be fully pertinent within the context of today’s research on these monuments. In addition, to facilitate future access to their work, this paper is accompanied by full translations into English and Spanish of the Leisners’s text on the Antequera megaliths.El sitio de los dólmenes de Antequera (Málaga, España), inscrito en la Lista del Patrimonio Mundial de UNESCO desde julio de 2016, cuenta con una historia de investigación de casi 200 años que se remonta al trabajo de Rafael Mitjana y Ardison en la década de 1840. Tras el descubrimiento del dolmen de Viera y el tholos de El Romeral, en 1903 y 1904 respectivamente, la investigación del gran sitio megalítico antequerano experimentó un fuerte impulso. Publicado en 1943, el primer volumen del gran corpus de monumentos megalíticos ibéricos de Georg y Vera Leisner (Die Megalithgräber der Iberischen Halbinsel. Erster Teil: Der Süden) habría de convertirse en el estudio más detallado del sitio antequerano durante toda la segunda mitad del siglo XX, a pesar de que el hecho de estar publicado en alemán lo hacía de difícil acceso para muchos estudiosos españoles. En este artículo revisamos la importancia de la obra de los Leisners para entender los megalitos antequeranos a la luz de los resultados de las investigaciones que se vienen desarrollando desde hace 15 años. Son muchas las cuestiones planteadas en la obra del matrimonio alemán que siguen teniendo plena vigencia en la investigación actual de estos monumentos. Además, para facilitar el futuro acceso a su obra, el texto se acompaña de sendas traducciones al inglés y al español

Increasing the Intelligence of Virtual Sales Assistants through Knowledge Modeling Techniques

Shopping agents are web-based applications that help consumers to find appropriate products in the context of e-commerce. In this paper we argue about the utility of advanced model-based techniques that recently have been proposed in the fields of Artificial Intelligence and Knowledge Engineering, in order to increase the level of support provided by this type of applications. We illustrate this approach with a virtual sales assistant that dynamically configures a product according to the needs and preferences of customers

Building a decision support system with a knowledge modeling tool

Knowledge modeling tools are software tools that follow a modeling approach to help developers in building a knowledge-based system. The purpose of this article is to show the advantages of using this type of tools in the development of complex knowledge-based decision support systems. In order to do so, the article describes the development of a system called SAIDA in the domain of hydrology with the help of the KSM modeling tool. SAIDA operates on real-time receiving data recorded by sensors (rainfall, water levels, flows, etc.). It follows a multi-agent architecture to interpret the data, predict the future behavior and recommend control actions. The system includes an advanced knowledge based architecture with multiple symbolic representation. KSM was especially useful to design and implement the complex knowledge based architecture in an efficient way