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Mechanical Engineering. 2007;129(03):24-29. doi:10.1115/1.2007-MAR-1.
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This article discusses growing role of silicon microelectron-mechanical systems (MEMS) technology in automotive and consumer products, telecommunications, radio-frequency applications, and medical care. The article also highlights that silicon-based MEMS devices must be constructed in clean rooms, such as one at Sandia's Microelectronics Development laboratory. According to engineers, the search for an in-depth understanding of wear mechanisms in dynamic silicon MEMS is expected to drive an ambitious wave of leading-edge research into microscale science and engineering, distinct from that which prevailed at the mesoscale. It has been found that gas damping between MEMS structures and the substrate, within the sealed package, can cause serious nonlinearities. While this doesn't lead to failure in the classic sense, it may make it harder to close a switch. On the plus side, gas damping can provide a cushion that enables a MEMS device to survive surprisingly high shock loads.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2007;129(03):30-33. doi:10.1115/1.2007-MAR-2.
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This article focuses on research and development works in the field of silicon-gas turbine engines to enable them produce power for portable devices. Alan Epstein, a professor of aeronautics and astronautics at the Massachusetts Institute of Technology, and his team are working on tiny silicon gas-turbine engines that could soon power laptops or cell phones. The group chose pressurized gas bearings, which can hold more weight relative to their size as they get smaller. Thrust bearings with spiral grooves and holes in their centers are self-pumping and keep the rotor in the right position. Epstein’s group considered magnetic bearings early on, but found that in addition to the manufacturing difficulties, the magnetic materials had too Iowa Curie point and would not stay magnetic at the temperatures at which the engine would operate: Instead, they chose pressurized gas bearings, which conveniently can hold more weight relative to their size as they get smaller. Thrust bearings with spiral grooves and holes in their centers are self-pumping and keep the rotor free and in the right position. While there is clearly plenty of room for improving efficiency, the microengine may very well end up as the only significant way to power, say, a laptop, an iPod, or a soldier's thermal weapon sight, to say nothing of a palm-size plane.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2007;129(03):34-35. doi:10.1115/1.2007-MAR-3.
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Medical researchers have discovered that the best way to operate microscale devices is through intuitive controls. According to researchers, a joystick can be very disruptive, instead, if it feels like you're holding on to the handle of an instrument and it's just following your hand; it's completely intuitive. A system developed by Johns Hopkins University translates hand movements into motions that are smooth and precise enough to inject minuscule arteries. The steady hands system is still a laboratory curiosity, to be sure. However, it has shown great promise in the experiments Taylor and his colleagues have performed to date. A microdevice that the team has built has displayed five-micrometer precision. A microscale device could make this near-impossible task routine by injecting blood thinner directly into the affected vessel. One issue that would have to be worked out, however, is immobilizing the patient: even motion calibrated to mere micrometers could do damage if the patient's eyeball moves.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2007;129(03):36-38. doi:10.1115/1.2007-MAR-4.
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This article focuses on developments in the enterprise resource planning (ERP) systems. The way companies acquire ERP services in the future will likely change radically, too. Midsize companies can expect to say goodbye to the large-scale systems and their steep training curves by letting someone else house the system and worry about maintenance. ERP systems link manufacturing with business processes like new orders, purchasing, credit, accounting, supply chain management, and planning. Vendors are looking to catch the attention of potential clients and get them back on board and away from the workaround. Businesse s looking for the capabilities that ERP can give them minus its headaches will more often turn to outside services. In an outsourcing scenario, a company uses some or all the modules in an ERP system over a secure network link to the service's computer center. Although ERP systems have been perceived as clunky and expensive of late, the industry is far from moribund. In fact, the applications are becoming nimbler and have the potential to become even more practical in the years ahead.

Commentary by Dr. Valentin Fuster

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