Identity and security in the competition for power in Israel

The language of security has immediate effects; it constitutes a speech act. By using the language of security, an actor reclaims the use of extraordinary media in order to deal with the threats that it presents to public opinion; this is called securitisation. However, security is not always objective, and sometimes the interests of specific sectors in their competition for power are concealed behind the argument of general interest. Starting from a concept of enlarged security, we propose a review of the concept of societal security as described by Barry Buzan and Ole Waever, which suggests a security based on the identity of communities, and we do so by focusing on the experience of Israel, where security and identity go hand-in-hand in the discourse. We also add a proposal from the sociology of power: the discourse of security is just another resource in the competition for power

Feature selection for microarray gene expression data using simulated annealing guided by the multivariate joint entropy

In this work a new way to calculate the multivariate joint entropy is presented. This measure is the basis for a fast information-theoretic based evaluation of gene relevance in a Microarray Gene Expression data context. Its low complexity is based on the reuse of previous computations to calculate current feature relevance. The mu-TAFS algorithm --named as such to differentiate it from previous TAFS algorithms-- implements a simulated annealing technique specially designed for feature subset selection. The algorithm is applied to the maximization of gene subset relevance in several public-domain microarray data sets. The experimental results show a notoriously high classification performance and low size subsets formed by biologically meaningful genes.Postprint (published version

Feature selection in proton magnetic resonance spectroscopy data of brain tumors

In cancer diagnosis, classification of the different tumor types is of great importance. An accurate prediction of different tumor types provides better treatment and may minimize the negative impact of incorrectly targeted toxic or aggressive treatments. Moreover, the correct prediction of cancer types using non-invasive information –e.g. 1H-MRS data– could avoid patients to suffer collateral problems derived from exploration techniques that require surgery. A Feature Selection Algorithm specially designed to be use in 1H-MRS Proton Magnetic Resonance Spectroscopy data of brain tumors is presented. It takes advantage of a highly distinctive aspect in this data: some metabolite levels are notoriously different between types of tumors. Experimental read- ings on an international dataset show highly competitive models in terms of accuracy, complexity and medical interpretability.Postprint (author’s final draft

TFS: a thermodynamical search algorithm for feature subset selection

This work tackles the problem of selecting a subset of features in an inductive learning setting, by introducing a novel Thermodynamic Feature Selection algorithm (TFS). Given a suitable objective function, the algorithm makes uses of a specially designed form of simulated annealing to find a subset of attributes that maximizes the objective function. The new algorithm is evaluated against one of the most widespread and reliable algorithms, the Sequential Forward Floating Search (SFFS). Our experimental results in classification tasks show that TFS achieves significant improvements over SFFS in the objective function with a notable reduction in subset size.Peer ReviewedPostprint (published version

Differentiation of glioblastomas and metastases using 1H-MRS spectral data

Hydrogen-1 magnetic resonance spectroscopy (1H-MRS) allows noninvasive in vivo quantification of metabolite concentrations in brain tissue. In this work two of the most aggressive brain tumors are studied with the purpose of differentiating them. The challenging aspect in this task resides in that their radiological appearance is often similar, despite the fact that treatment of patients suffering these conditions is quite different. Efforts to differentiate between these two profiles are getting increasing attention, mainly because the consequences of performing an incorrect diagnosis. Due to the high dimensionality, initiatives oriented to reduce the description complexity become important. In this work we present a feature selection algorithm that generates relevant subsets of spectral frequencies. Experimental results deliver models that are both simple in terms of numbers of frequencies and show good generalization capabilities.Postprint (author’s final draft

Machine learning methods for classifying normal vs. tumorous tissue with spectral data

Machine learning is a powerful paradigm within which to analyze 1H-MRS spectral data for the automated classi¯cation of tumor pathologies aimed to facilitate clinical diagnosis. The high dimensionality of the involved data sets makes the discover of computational models a challenging task. In this study we apply a feature selection algorithm in order to reduce the complexity of the problem. The obtained experimental results yield a remarkable classification performance of the final induced models, both in terms of prediction accuracy and number of involved spectral frequencies. A dimensionality reduction technique that preserves the class discrimination capabilities is used for the visualization of the final selected frequencies, thus enhancing their interpretability.Peer ReviewedPostprint (author’s final draft

GENERALIDADES DE LA FORMACIÓN, PREVENCIÓN Y TRATAMIENTO DE DEPÓSITOS DE ESCAMAS

RESUMENLas escamas son uno de los problemas más complejos y molestos de manejar que se pueden presentar a lo largo del sistema de producción cuando se presentan cambios físicos y/o químicos signifcativos a través de este. El presente trabajo discute detalladamente cada una de las características de los depósitos minerales (como también se conoce a las escamas), y se analiza como varía el comportamiento de los compuestos responsables de la formación de escamas, tales como: el carbonato de calcio, los sulfatos de calcio, bario y estroncio y algunos compuestos de hierro cuando propiedades del agua como el pH, la temperatura, la presión y la cantidad de sales disueltas son manipuladas. Dos técnicas de remoción de escamas son presentadas; la primera de ellas se caracteriza por el tratamiento a partir de productos químicos  que disuelven los depósitos ya formados, mientras que la segunda  se basa en la remoción mecánica de dichos depósitos. Estas técnicas pueden ser usadas individualmente o en conjunto. Además, presenta  los métodos  más utilizados en campo para la prevención de escamas.Los depósitos de escamas representan un problema serio para la industria de los hidrocarburos; el cual debe ser resuelto escogiendo la técnica adecuada ya sea para prevenir su formación o para remover los depósitos ya formados, ya que de no hacerlo problemas de taponamiento impedirían el desplazamiento adecuado de los fuidos de producción provocando con esto grandes pérdidas económicas. Palabras clave: Depósitos de escamas, Control de escamas, precipitación de material mineralABSTRACTScales are one of  the most complex and  troublesome problems  to manage  that may occur along  the production  system when  there  are  signifcant  physical  and  /  or    chemical  changes  through  it. The present paper discusses  in detail  each of  the  characteristics of mineral deposits  (also known  as  the scale), and discusses how varies the behavior of compounds responsible for the formation of scales, such as calcium carbonate, Calcium sulfate, barium and strontium and  iron compounds where some properties of water as pH, temperature, pressure and the amount of dissolved salts are manipulated.Two scale removal techniques are presented in this investigative report; the frst one is the treatment with Chemicals products  which dissolve the already formed deposits, while the second one is based on  the  mechanical  remotion  of  such  deposits.  These  techniques  may  be  used  individually  or  in combination.  The most used feld methods for scale prevention are also presented.As  a  result of  this  review  it was  found  that  scales deposits  represent  a  serious problem  for  the oil industry, which must be solved by choosing the appropriate technique to prevent either its formation or to remove the deposits already formed, since failing to do so, will produce problems that will prevent adequate productions fuid displacement causing major economics losses.Keywords: Scale deposit, scale control, mineral precipitatio

UNA NUEVA MIRADA A LA COMBUSTIÓN IN-SITU: TRATANDO DE ROMPER UN VIEJO PARADIGMA

RESUMENDado el creciente interés por el aumento en las reservas de crudo pesado en muchos países, entre estos Colombia, ha surgido la combustión in situ como un método alternativo para extraer petróleo pesado, donde otras técnicas, debido a las condiciones del yacimiento, no son las más apropiadas. Actualmente existe una considerable proporción de expertos en el ámbito petrolero, que no conciben la aplicación de dicha técnica en escala de campo debido a sus antecedentes. Por esta razón este artículo busca brindar al lector una percepción distinta de la técnica a partir de nuevas teorías y nuevas maneras de tratar un proceso de tan alta complejidad. En el presente estudio se establecen algunas consideraciones acerca de los mecanismos que se presentan, el origen y evolución de la técnica, variaciones de la técnica, pruebas de laboratorio, pautas para el modelamiento numérico y algunas consideraciones de diseño.Palabras claves: Combustión In situ, Inyección de Aire, Métodos de recobro mejorado de crudo, Crudos pesadosABSTRACTGiven the recent interest in increasing heavy oil reserves in many countries, Colombia among them, interest has been created for in situ combustion as an alternative method to extract oil where other techniques, provided the reservoir conditions, are not feasible. Nevertheless, there exists a significant amount of experts that do not conceive the application of this technique in a field scale due to its precedents. This article tries to give the reader a different view of the technique from new theories and new ways of treating a complex process as this one. Considerations regarding recovery mechanisms are presented, as well as the origin and evolution of the technique, its variations, laboratory tests, guidelines for numerical modeling and some design considerations.Keywords: In-Situ Combustion, Air Injection, Fire-flooding, Enhanced Oil Recovery, Heavy Oil

Simulation of a waterflooding process in a physical scaled model 3d

 The objective of this work is to show the proceedings to simulate a water injection process in the Radial Displacement Equipment, EDR. The methodology used the recognizability of the parts that make, training in handling and operation, selection of packaging technique of the porous medium. Packing technique selected considering the structural stability, repeatability and reproducibility of the petrophysical properties and construction time, it was proposed a method for the manufacture of synthetic porous media to physical models. Additionally, by carrying out preliminary tests on models in acrylic and the EDR were identified and implemented improvements to ensure the success of the tests which include technical testing procedures, data collected management, packaging to be used and the system monitoring / control. Finally, displacement process was simulated in the EDR presenting the results of tests carried.En el presente trabajo se muestra el proceso para simular un proceso de inyección de agua en el Equipo de Desplazamiento Radial, EDR. La metodología empleada, fue el conocimiento de las partes que lo conforman, el entrenamiento en su manejo y operación, la selección de la técnica de empaquetamiento del medio poroso. Seleccionada la técnica de empaquetamiento teniendo en cuenta la estabilidad estructural, la repetitividad y reproducibilidad de las propiedades petrofísicas y el tiempo de construcción, se planteó un procedimiento para la fabricación de medios porosos sintéticos para modelos físicos. Adicionalmente, mediante la realización de pruebas preliminares en modelos en acrílico y en el EDR se identificaron e implementaron mejoras para garantizar el éxito de las pruebas las cuales incluyen procedimientos técnicos de ensayo, manejo de los datos obtenidos, los empaques a emplear y el sistema de monitoreo/control. Finalmente, se simuló físicamente un proceso de desplazamiento en el EDR presentando los resultados obtenidos de las pruebas realizadas. &nbsp