Abstract-A piezoelectrically driven hydraulic amplification microvalve for use in compact high-performance hydraulic pumping systems was designed, fabricated, and experimentally characterized. High-frequency, high-force actuation capabilities were enabled through the incorporation of bulk piezoelectric material elements beneath a micromachined annular tethered-piston structure. Large valve stroke at the microscale was achieved with an hydraulic amplification mechanism that amplified (40 50 ) the limited stroke of the piezoelectric material into a significantly larger motion of a micromachined valve membrane with attached valve cap. These design features enabled the valve to meet simultaneously a set of high frequency ( 1 kHz), high pressure( 300 kPa), and large stroke (20-30 m) requirements not previously satisfied by other hydraulic flow regulation microvalves. This paper details the design, modeling, fabrication, assembly, and experimental characterization of this valve device. Fabrication challenges, such as deep-reactive ion etching of the piston and valve membrane structures, wafer-level silicon-to-silicon fusion bonding, wafer-level and die-level silicon-to-glass anodic bonding, preparation and integration of piezoelectric material elements within the micromachined tethered piston structure, and filling of degassed fluid within the hydraulic amplification chamber are detailed.[829]

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This paper challenges some fundamental aspects of research and conclusions relating to the use of technology for community development. Views of technology, in this case the mobile phone, as a tool for increased economic welfare are often skewed due to extreme reductionism, ambiguous interview questions and poor data sources. Research of complex social systems or sub-systems give the wrong answers when reductionist methodologies are used. To demonstrate such shortcomings, the 2007 paper of Robert Jensen serves as an example. His conclusion that mobile phones enable Kerala fishermen to increase their economic welfare is the most cited paper on ICT4D topics, but there are fundamental methodological and logical problems with the claim, while other research came to contradictory conclusions. This critique is presented on many levels: ideological, paradigmatic, methodology, logical, statistical and semantic.

With the continued proliferation of display intensive applications for portable electronics devices, the need for lower power, higher image quality video displays has never been greater. Pixtronix is uniquely able to meet these requirements through its MEMS (micro-electo-mechanical system) display technology, which enables the development of direct view displays with breakthrough optical transmission over 60%, color gamut over 100% (of NTSC, CIE 1931), 1,000:1 contrast ratio and wide view angles.

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