Investigación de Operaciones

Revista Electrónica y Servicio No. 155 presenta: Servicio técnico · Inversores de voltaje en televisores LCD · Memorias EEPROM en televisores · Conversión de la fuente conmutada de hornos inverter en una fuente con transformador · Reparaciones comunes en iPods (segunda parte) · Televisores: solución de fallas ocasionadas por la memoria EEPROM Perfil tecnológico · Autos y electrónica, un matrimonio para siempre

In the beginning, Earth was an inhospitably alien place―in constant chemical flux, covered with churning seas, crafting its landscape through incessant volcanic eruptions. Amid all this tumult and disaster, life began. The earliest living things were no more than membranes stretched across microscopic gaps in rocks, where boiling hot jets of mineral-rich water gushed out from cracks in the ocean floor. Although these membranes were leaky, the environment within them became different from the raging maelstrom beyond. These havens of order slowly refined the generation of energy, using it to...

Of all the different areas in computational chemistry, density functional theory (DFT) enjoys the most rapid development. Even at the level of the local density approximation (LDA), which is computationally less demanding, DFT can usually provide better answers than Hartree-Fock formalism for large systems such as clusters and solids. For atoms and molecules, the results from DFT often rival those obtained by ab initio quantum chemistry, partly because larger basis sets can be used. Such encouraging results have in turn stimulated workers to further investigate the formal theory as well as...

La NASA está en un punto crítico; después de décadas de supremacíamundial, canceló su programa de transbordadores cerrando su acceso al espacio. Hasta 2020, ningún astronauta será lanzado fuera de la órbita terrestre desde suelo estadounidense, y pronto su programa espacial podría ser eclipsado por el de otros países. Con su característico humor y sus provocadoras ideas, Neil deGrasse Tyson, el célebre presentador del programa Cosmos, ilumina el pasado, el presente y el futuro de la exploración del espacio y nos recuerda de manera brillante por qué la NASA importa más que...