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Ítem Delay spread in mmwave bands for indoor using Game Engines 3D Ray based Tools(Institute of Electrical and Electronics Engineers Inc., 2016-04-10) Cruz, WilliamSimulation results of channel parameters using a Game Engine Ray Based Tool in different operating systems with different hardware architectures and using an open source 3D modeling tool for an indoor scenario are presented in this paper. We present simulation results and compare them with a set of measurements for an indoor scenario in the 5.4 GHz band, obtaining good matches between the rays traced by the tool and measurements for delay spread.Ítem Identifying competitive interaction of patterns in software product lines(Universidad de Santiago de Cali, Facultad de Ingeniería, Facultad de Ciencias Básicas, 2015-07-01) Arboleda, HugoLos patrones de diseño para empresas (tales como los patrones JEE) pueden ser usados para promover Atributos de Calidad [Quality Attributes, QA] como funcionalidades cuando se derivan en una línea de productos software [Software Product Line, SPL]. Uno de los aspectos encontrados en la derivación de productos es la interacción de fragmentos de código generados por la aplicación de patrones. Esta interacción puede ser colaborativa o de competitiva. Cuando es competitiva, las relaciones pueden ser adaptables o excluyentes. En ambos casos, los diferentes enfoques (e.g., la composición patrón, el patrón de sustitución, el razonamiento de restricción) se pueden usar para abordar el problema. Sin embargo, la identificación y predicción temprana de estas interacciones puede ser útil para desarrollar estrategias adecuadas. Este trabajo explora e identifica las interacciones usando dos repositorios base: QAs de un reconocido estándar y patrones de un catálogo. Se muestran dos casos de interacción funcional, cuando se promueven niveles específicos de QA en una aplicación empresarial [SPL].Ítem Calibración Basada en Medidas para Modelos de Trazado de Rayos en 3D para Ambientes Exteriores Urbanos andinos(Universidad Icesi, 2012-04-01) Guevara Ibarra, Dinael; Navarro Cadavid, Andrés; Africano, María VictoriaDue to the complexity of a real situation, estimation of path loss using the ray-tracing method usually assumes one or three large classes of homogeneous materials to represent the building walls, building roofs and street floors in order to have a viable model of the 3D environment. However, in a real case, an outdoor environment consists of many buildings and streets made of heterogeneous materials. Additionally, the characterizations of these classes of materials are usually taken from research of other authors with specific materials on site and often not done for the frequency band of operation. We analyze the behavior of the statistical variation of standard deviation, correlation coefficient and the average error between the values of estimated and measured path loss data when considering various values of permittivity of these three classes. Finally, we adjust the values of permittivity, obtaining a reasonable improvement of ray tracing to estimate the path-lossÍtem Arquitectura de un Sistema de Monitoreo Radioeléctrico usando Software Defined Radio(Universidad Icesi, 2012-10-01) Arteaga Arce, AdrianaSpectrum monitoring is an essential task to be performed for a country administration to control and monitor its use. Its main components are the monitoring equipment (i.e. spectrum analyzers, antennas and GPS) which are arranged in strategic locations throughout a territory to get information about the characteristics of radio services. There is a special interest to complement this system with simpler and more portable equipment, to get much spectrum information, mainly in areas that cannot be reached through the main monitoring network. An alternative is to use Software Defined Radio (SDR), a technique to build devices that can replace some hardware by software routines, thus reducing costs and size. In industry there are different equipment and programming tools to build flexible devices, easily upgradeable and reconfigurable for specific tasks. This paper describes the main components of a monitoring system developed with SDR, and the tools used to implement it.Ítem Arquitectura empresarial para corresponsales no bancarios(Universidad Icesi, 2011-01-01) Rodríguez de Silvestre, Carlos Eduardo; Arboleda Jiménez, Hugo Fernando; Asesor TesisLa arquitectura empresarial permite alinear el desarrollo tecnológico de una organización con su visión y estrategia. El presente trabajo de grado propone una solución tecnológica al procesamiento transaccional de CNB para entidades financieras en Colombia, mitigando riesgos de operación y reduciendo los limites impuestos por el manejo del efectivo en poblaciones remotas, enmarcada dentro de TOGAF como marco de referencia de arquitectura empresarial. El desarrollo de la arquitectura parte de las necesidades del negocio, continua con la visión de la arquitectura, la definición de la arquitectura de negocio, la arquitectura de datos, la arquitectura de aplicaciones, la arquitectura tecnológica y los proyectos requeridos para la implementación de la arquitectura propuesta..Ítem Calidad de Servicio en Proveedores de Servicios IPTV(Universidad Santiago De Cali, 2012-01-01) García, Ángela AndreaLa posibilidades de interactividad propias de la IPTV (e.g., video bajo demanda, pago por ver, E-Learning), hacen prever, a corto plazo, el fortalecimiento de su presencia en el país. Esa masificación, sumada al hecho de ser un servicio que se presta en tiempo real y a su reconocida sensibilidad a la latencia, los retardos y la pérdida de paquetes, constituyen un reto para proveer un servicio que reúna las expectativas de calidad de sus usuarios. En esa tarea, administrar la prioridad en el tráfico puede ser fundamental. Los mecanismos de QoS (Quality of Service) pueden ser un gran aliado, al permitir el manejo rápido de aplicaciones de misión crítica. El artículo inicia con una visión general de la IPTV, sus servicios y arquitectura; la presentación de algunos conceptos aplicados al tema (e.g. QoS, QoE, IPTV sobre ADSL) y cierra con la presentación de mecanismos de calidad de servicio aplicados a IPTV y una valoración de la situación de dos proveedores de este servicio en Colombia. Calidad de Servicio en Proveedores de Servicios IPTV (PDF Download Available). Available from: https://www.researchgate.net/publication/270589568_Calidad_de_Servicio_en_Proveedores_de_Servicios_IPTV [accessed May 25, 2016].Ítem A Model to Guide Dynamic Adaptation Planning in Self-Adaptive Systems(Elsevier, 2016-03-14) Arboleda Jiménez, Hugo FernandoSelf-adaptive enterprise applications have the ability to continuously reconfigure themselves according to changes in their execution contexts or user requirements. The infrastructure managing such systems is based on IBM's MAPE-K reference model: a Monitor and an Analyzer to sense and interpret context data, a Planner and an Executor to create and apply structural adaptation plans, and a Knowledge manager to share relevant information. In this paper we present a formal model, built on the principles of constraint satisfaction, to address dynamic adaptation planning for self-adaptive enterprise applications. We formalize, modify and extend the approach presented in [H. Arboleda, J. F. Díaz, V. Vargas, and J.-C. Royer, "Automated reasoning for derivation of modeldriven spls," in SPLC'10 MAPLE'10, 2010, pp. 181-188] for working with self-adaptation infrastructures in order to provide automated reasoning on the dynamic creation of structural adaptation plans. We use a running example to demonstrate the applicability of such model, even in situations where complex interactions arise between context elements and the target self-adaptive enterprise application.Ítem A multihop-authenticated proxy mobile IP scheme for asymmetric VANETs(IEEE Transactions on Vehicular Technology, 2013-01-01) Cespedes Umaña, Sandra LorenaVehicular communications networks are envisioned for the access to drive-thru Internet and IP-based infotainment applications. These services are supported by roadside access routers (ARs) that connect vehicular ad hoc networks (VANETs) to external IP networks. However, VANETs suffer from asymmetric links due to variable transmission ranges caused by mobility, obstacles, and dissimilar transmission power, which make it difficult to maintain the bidirectional connections and to provide the IP mobility required by most IP applications. Moreover, vehicular mobility results in short-lived connections to the AR, affecting the availability of IP services in VANETs. In this paper, we study the secure and timely handover of IP services in an asymmetric VANET and propose a multihop-authenticated Proxy Mobile IP (MA-PMIP) scheme. MA-PMIP provides an enhanced IP mobility scheme over infrastructure-to-vehicle-to-vehicle (I2V2V) communications that uses location and road traffic information. The MA-PMIP also reacts, depending on the bidirectionality of links, to improve availability of IP services. Moreover, our scheme ensures that the handover signaling is authenticated when V2V paths are employed to reach the infrastructure so that possible attacks are mitigated without affecting the performance of the ongoing sessions. Both analysis and extensive simulations in OMNeT++ are conducted, and the results demonstrate that the MA-PMIP improves service availability and provides secure seamless access to IP applications in asymmetric VANETs. © 2013 IEEE.Ítem Component-based java legacy code refactoring(Universidad de Antioquia, 2013-09-01) Arboleda Jiménez, Hugo FernandoLa Ingeniería de Software Basada en Componentes (CBSE) pretende mejorar la modularización del software y la inserción de preocupaciones arquitecturales. Refactorizar código Java legado con CBSE en mente requiere evaluar primero el cumplimiento del código legado con los principios de la programación por componentes. En este artículo presentamos un portafolio de reglas para evaluar el cumplimiento de la propiedad de Integridad de Comunicación en código Java legado; esta propiedad es una de las mayores fortalezas del enfoque CBSE. Proponemos estas reglas para identificar tipos componente y así proveer una medida de la construcción de componentes CBSE de una aplicación. Con el objetivo de ayudar a los desarrolladores y al personal responsable del mantenimiento de código legado cuando se hace necesario refactorizar sus aplicaciones, nuestro trabajo nos lleva a definir un conjunto de acciones de refactorización. En este artículo también presentamos resultados de pruebas, comparaciones y análisis de las salidas logradas luego de refactorizar varias aplicaciones Java.Ítem VIP-WAVE: On the Feasibility of IP Communications in 802.11p Vehicular Networks(IEEE Institute of Electrical and Electronics Engineers Inc., 2012-12-26) Shen, XueminVehicular communication networks, such as the 802.11p and Wireless Access in Vehicular Environments (WAVE) technologies, are becoming a fundamental platform for providing real-time access to safety and entertainment information. In particular, infotainment applications and, consequently, IP-based communications, are key to leverage market penetration and deployment costs of the 802.11p/WAVE network. However, the operation and performance of IP in 802.11p/WAVE are still unclear as the WAVE standard guidelines for being IP compliant are rather minimal. This paper studies the 802.11p/WAVE standard and its limitations for the support of infrastructure-based IP applications, and proposes the Vehicular IP in WAVE (VIP-WAVE) framework. VIP-WAVE defines the IP configuration for extended and non-extended IP services, and amobilitymanagement scheme supported by Proxy Mobile IPv6 over WAVE. It also exploits multihop communications to improve the network performance along roads with different levels of infrastructure presence. Furthermore, an analytical model considering mobility, handoff delays, collisions, and channel conditions is developed for evaluating the performance of IP communications in WAVE. Extensive simulations are performed to demonstrate the accuracy of our analytical model and the effectiveness of VIP-WAVE in making feasible the deployment of IP applications in the vehicular network. © 2012 IEEE.