Universidad Tecnológica de Bolívar

About: Universidad Tecnológica de Bolívar is a education organization based out in Cartagena, Colombia. It is known for research contribution in the topics: AC power & Computer science. The organization has 507 authors who have published 724 publications receiving 3900 citations. The organization is also known as: UTB & Utb.

Path Planning for Non-Playable Characters in Arcade Video Games using the Wavefront Algorithm

Abstract: Search and planning is a common Artificial Intelligence task on videogames development. This exercise covers the design of Non-player character (NPC) behavior, content generation, and narrative's construction. This work focus on NPC behavior, specifically on path planning. This paper presents an implementation of an arcade videogame (Ms. Pacman type) with Unity, where the NPC's behavior (Ghosts) applies the Wavefront algorithm to find the shortest path to the Player Character (Mr. Pacman). This algorithm is an alternative to traditional algorithms the Djikstra algorithm and A-star used to solve this problem.

Efecto de las Lluvias sobre la Calidad del Agua en La Ciénaga Grande de Santa Marta, Colombia

Abstract: espanolSe estudio el efecto de las lluvias sobre la calidad delagua en la Cienaga Grande de Santa Marta(CGSM)-Caribe Colombiano, durante el periodo 2006 –2009. Se aplico el indicador ambiental de calidad deaguas marino-costeras para preservacion de flora yfauna, en seis zonas hidrobiologicamente comunes.El trabajo indico, que las precipitaciones a lo largode los anos escogidos, da como caracteristicas: queel mes para cada epoca seca es febrero y la lluvia seconcentra en octubre; ademas se relaciona el uso delos indicadores ambientales, como estrategia mundial,en pro de la toma de decisiones y la gestionambiental integral. El resultado mas relevante mostro,que los descriptores de calidad para el estadode naturalidad del sistema estuarino, esta entre losrangos bueno (51 - 75) y excelente (76 - 100). EnglishThe environmental indicator of quality of marinecoastal waters was determined, in Cienaga Grandede Santa Marta (CGSM), located on the Caribbeancoast in Colombia, during the period of 2006 to2009, by applying an index for the preservation offlora and fauna , the sampling points selected correspondto six common hydrobiological areas, inthe study were finding precipitations over the selectedyears, typical for each month dry season (February)and rainy season (October), also relates theuse of environmental indicators as global strategyof decision making and integrated environmentalmanagement, the most relevant result showed thatquality descriptors for the state of natural estuarinesystem is among the ranks good (51 - 75) and excellent(76-100).

Newman-Janis Ansatz in conformastatic spacetimes

Abstract: The Newman-Janis Ansatz was used first to obtain the stationary Kerr metric from the static Schwarzschild metric. Many works have been devoted to investigate the physical significance of this Ansatz, but no definite answer has been given so far. We show that this Ansatz can be applied in general to conformastatic vacuum metrics, and leads to stationary generalizations which, however, do not preserve the conformal symmetry. We investigate also the particular case when the seed solution is given by the Schwarzschild spacetime and show that the resulting rotating configuration does not correspond to a vacuum solution, even in the limiting case of slow rotation. In fact, it describes in general a relativistic fluid with anisotropic pressure and heat flux. This implies that the Newman-Janis Ansatz strongly depends on the choice of representation for the seed solution. We interpret this result as as a further indication of its applicability limitations.

Firewall-linux: una solución de seguridad informática para pymes (pequeñas y medianas empresas)

Abstract: RESUMEN Se facilita una solucion de seguridad de red personalizada de muy bajo costo para las pequenas y medianas empresas, permitiendoles identifcar y afrontar con precision los riesgos y tener una proteccion integral y completa. Se detectaron las necesidades que tienen las PYMES y se implemento un Servidor Firewall Linux. Basicamente se confgura un host con la herramienta Iptables para defnir la reglas de fltrado de paquetes segun las politicas de seguridad establecidas para la proteccion del fujo de datos entre dos redes. Se hizo un analisis funcional al frewall, instalando servicios a los hosts de las redes locales para verifcar la veracidad y factibilidad de las reglas confguradas, en el cual el comportamiento del frewall fue muy efectivo de acuerdo a las exigencias de las politicas de seguridad creadas. PALABRAS CLAVE: Seguridad Informatica, Pymes, Firewall, Linux Centos, Iptables. ABSTRACT It is facilitates a safety solution of personalized network of very low cost for the small and medium companies, allowing them to identify and to confront accurately the risks and to have an integral and complete protection. The needs of SMEs were detected and implemented a Linux Server Firewall. Basically you confgure a host with iptables tool to defne packet flter rules according to established security policies to protect the fow of data between two networks. It was done a functional analysis to frewall, installing services to hosts on local networks to verify the accuracy and feasibility of the confgured rules, in which the frewall behavior was very effective in accordance with the requirements of established security policies. KEY WORDS: Security Computer, Smes, Firewall, Linux Centos, Iptables. NOTA: Este articulo de la Revista UIS Ingenierias es publicado por EBSCO en la base de datos “Fuente Academica”. Para poderlo observar se debe tener suscripcion con EBSCO, en el siguiente enlace: ARTICULO PUBLICADO EN EBSCO

A Sequential Quadratic Programming Model for the Economic–Environmental Dispatch in MT-HVDC

Abstract: This paper addresses the economic-environmental dispatch problem for thermal plants on a Multi-terminal HVDC power grid. A multi-objective optimization approach is used for modeling the compromise between fuel costs and the greenhouse gas emissions by the thermal plants. The grid topology is also considered by proposing a convex reformulation of the power balance equations through Taylor’s series expansion method. To eliminate the error introduced by this linear approximation a sequential quadratic programming approach is applied by solving the multi-objective problem by a single-objective equivalent via weighting factor approach. A standard 6-node HVDC system is used to validate the proposed convex formulation. All simulations are performed in MATLAB with the quadprog optimization package.