MEMs

Genetic Studies of Responses of Bones to Mechanical Stresses

Progress has been reported in a continuing program of molecular genetic studies of the responses of bones to mechanical stresses. Prior studies in mice and humans had provided evidence that mechanical loading stimulates bone formation and that immobilization or loss of mechanical stimulation leads to decreasing bone formation and increasing bone loss. Other prior studies in humans and mice had demonstrated that bone anabolic response differs widely among individuals subjected to the same degree of mechanical loading. The initiation of the present studies was motivated by the conjecture that variations in bone anabolic response among individuals are attributable to differences in the transcription levels of genes; that is, they are genetically controlled.

Posted in: Briefs, Medical
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Characterization of a MEMS Directional Sound Sensor

There is a wide range of potential military applications in which ambiguity in bearing occurs with respect to sound. For example, autonomous unmanned aerial vehicles (UAVs) could employ a sensor to determine the bearing of an explosion and conduct battle damage assessment (BDA) on it. With existing sensors this is difficult to do because the explosion is too short in duration to use the Doppler effect to determine the bearing. Also, an autonomous underwater vehicle (AUV) acting as a quiet platform to tow a short, omni-directional hydrophone array must contend with bearing ambiguity.

Posted in: Briefs, Physical Sciences
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Two-Camera Imaging System for Kinematic Measurements

A high-speed imaging system has been devised as a noninvasive means of collecting data on the kinematics of working models of developmental underwater or aerial vehicles that would utilize flapping fins or flapping wings for propulsion. The system includes two high-speed digital electronic cameras aimed along orthogonal axes that acquire snapshots of a model simultaneously in rapid succession. The data from successive images are postprocessed to obtain three-dimensional coordinates of points of interest on the model as functions of time. In the case of a flapping appendage, the points of interest are tips on the appendage, and the temporal evolution of the tip coordinates through multiple flapping cycles is utilized, in conjunction with computational fluid dynamics and other analytical tools, in an iterative process of testing and design directed toward improving the swimming or flying performance of the model. The system can, of course, be used as a noninvasive means of kinematic testing of models other than those of vehicles utilizing flapping appendages.

Posted in: Briefs, Physical Sciences
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Synthesizing Pseudo-Finer-Resolution MODIS Data Products

A document discusses a methodology for synthesizing finerresolution data products from outputs of the Moderate Resolution Imaging Spectroradiometer (MODIS) instruments aboard NASA's Terra and Aqua satellites. Typical MODIS ocean color data have 1-km resolution, but those in five wavelength bands have 500-m resolution and those in two wavelength bands have 250-m resolution. Finer-resolution bio-optical-property data products improve our capability for monitoring coastal ocean and estuarine processes.

Posted in: Briefs, Physical Sciences
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Infrastructure for Development of Secure, Reliable Software

The Verification and Automated Reasoning research group at Cornell University has been building an infrastructure, comprising human expertise and computational resources, for the development of secure, reliable software for critical military applications. Such software includes distributed real-time embedded software systems, which are inherently complex and difficult to understand and specify. The infrastructure includes both efficient means of constructing the software and mathematically rigorous means of ensuring that the software will be secure and correct by construction.

Posted in: Briefs, Information Technology
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A Formal Model of the Attack Surface of a Software System

A formal model has been devised to impart some mathematical rigor to the concept of the attack surface of a software system. Complementing the model is a definition of a quantitative measure of the attack surface as an indicator of the relative insecurity of the system (the larger the attack surface, the more insecure the system). The model and the quantitative measure are intended to serve as systematic means of assessing progress in the development of secure software; they are expected to be especially valuable for evaluating the relative degree of security of two successive versions of nominally the same computer program.

Posted in: Briefs, Information Technology
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Deciphering the New SUMIT™ Specification

The new SUMIT specification is managed by the Small Form Factor Special Interest Group (SFF-SIG). SFF-SIG is a newly formed, non-profit industry group that develops, promotes, and supports small form factor circuit board specifications and related technologies. The group embraces the latest technologies, but also has a philosophy of maintaining legacy compatibility and enabling smooth transitions to next-generation interfaces.

Posted in: Articles, Articles, Embedded Technology, Board-Level Electronics, Electronics & Computers, Computer software / hardware, People and personalities, Terminology
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Applying Cognitive Memory to Pattern Recognition

Whether you are involved in robotics or other domains, pattern recognition is essential to progress. A new device, called the CogniMem chip, offers a hardware solution to this problem. CogniMem can be considered a true Artificial Intelligence device because it has been designed specifically for the purpose of learning, memorizing and recognizing.

Posted in: Articles, Articles, Embedded Technology, Board-Level Electronics, Electronics & Computers, Artificial intelligence, Electronic equipment, Neural networks
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Direct Spray Liquid Cooling Systems

For decades military platforms have included electronics for avionics, vehicle controls, radios, radar, sonar and fire control. From a computational standpoint most of these systems could be accomplished with relatively low power devices. There have always been higher performance electronics for applications such as radar processing, Intelligence, Surveillance, and Re - connaissance (ISR) processing, and mission computing; however, high performance electronics were relegated to stationary, benign environments. Due to bandwidth limitations of secure communications between command centers and front line troops, trends to include these computationally intense applications on vehicles and aircraft exist. From airborne platforms such as U-2 Dragon Lady and Global Hawk operating up to 70,000 feet and -65°C, to a surface-to-air missile launcher mounted on a 5-ton truck called Medium Extended Air Defense System (MEADS) in a scorching +60°C desert, the military is deploying incredible performance in harsh environments. To fit on these military vehicles, the size, weight and power (SWaP) of the electronic systems are minimized to extend the range of airborne platforms or allow ground vehicle transport with a wider range of operation. Direct spray cooling systems are enabling these programs with minimal SWaP budgets and harsh environmental requirements to use lower cost, high performance embedded electronics.

Posted in: Articles, Articles, Embedded Technology, Board-Level Electronics, Electronics & Computers, Electronic equipment, Cooling, Durability, Reliability
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Nanostructured Ferromagnetic-Wire/Insulator Composites

A research and development effort now in progress is focused on nano-structured ferromagnetic- wire/insulator composite materials to be used as the magnetic-core materials of sensors for measuring weak magnetic fields. Figure 1 schematically depicts an example of such a sensor — a flux-gate magnetometer that resembles a traditional orthogonal flux-gate magnetometer except that, instead of a single cylindrical ferromagnetic core, there are multiple parallel ferromagnetic wire cores packed together with insulating material between them. An overriding consideration in the design, fabrication, and operation of such a magnetometer is that high effective magnetic permeability of the core is necessary as one of the prerequisites for obtaining high sensitivity.

Posted in: Briefs, Physical Sciences
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