Engineering topics
Publications and source records attributed to Garcia, Pablo.
There are urgent calls to action by the NAE, the Nobel Prize Summit, the UN, and global scientists to address and solve, in this decade (2020 – 2030), crucial and widely recognized global challenges to peace and security before they become more complex and more environmentally, financially, and socially costly; before we reach the point of no return.
A novel implementation of an isolated gate driver for power switches is proposed in this study. The driver is bespoke designed for SiC power mosfet s. The proposal achieves the main driver characteristics—isolation capability, gate switching command, and power transfer to the secondary side by using a unique magnetic transformer. The resulting simple circuitry enables the integration of the driver into the power cell, achieving theoretical higher power density values of the final system. The principle of operation of the driver is described in detail. The original pulsewidth modulation signal is modulated with a pure ac square waveform under a two-level modulation scheme, that guarantees no saturation of the magnetic core. Here, the signal is then magnetically coupled to the secondary side, where it is rectified and reconstructed to effectively drive the target device. In addition, the steps needed to provide a suitable design taking into account the parameters of the target power switch are also detailed. The resulting driver is characterized and a prototype of the driver is built and tested. The main results of the driver performance on a SiC mosfet -based prototype are presented. Based on the analysis of these results, this study experimentally demonstrates the feasibility of the proposal.
Abstract not provided
Sandia National Laboratories hosted a workshop on the future of infrastructure security on February 27-28, 2013, in Albuquerque, NM. The 17 participants came from backgrounds as diverse as federal policy, the insurance industry, infrastructure management, and technology development. The purpose of the workshop was to surface key issues, identify directions forward, and lay groundwork for cross-sectoral and cross-disciplinary collaborations. The workshop addressed issues such as the problem space (what is included in infrastructure problems?), the general types of threats to infrastructure (such as acute or chronic, system-inherent or exogenously imposed) and definitions of secure and resilient infrastructures. The workshop concluded with a consideration of stakeholders and players in the infrastructure world, and identification of specific activities that could be undertaken by the Department of Homeland Security (DHS) and other players.