Special Coverage

Distributed Propulsion Concepts and Superparamagnetic Energy Harvesting Hummingbird Engine
Wet Active Chevron Nozzle for Controllable Jet Noise Reduction
Magnetic Relief Valve
Locking Mechanism for a Flexible Composite Hinge
Active Aircraft Pylon Noise Control System
Unmanned Aerial Systems Traffic Management
Method of Bonding Dissimilar Materials
Sonar Inspection Robot System

Magnetic Compensation for Second-Order Doppler Shift in LITS

Fractional frequency stability could be the lowest ever achieved. The uncertainty in the frequency of a linear- ion-trap frequency standard (LITS) can be reduced substantially by use of a very small magnetic inhomogeneity tailored to compensate for the residual second-order Doppler shift. An effect associated with the relativistic time dilatation, one cause of the second-order Doppler shift, is ion motion that is attributable to the trapping radio- frequency (RF)electromagnetic field used to trap ions. The second- order Doppler shift is reduced by using a muli-pole trap; however it is still the largest source of systematic frequency shift in the latest generation of LITSs, which are among the most stable clocks in the world. The present compensation scheme reduces the frequency instability of the affected LITS to about a tenth of its previous value.

Posted in: Briefs, Physical Sciences


Static vs. Dynamic Detection of Bugs in Safety-Critical Code

In the never-ending quest to produce high-quality software, traditional dynamic testing plays a fundamental role. The weakness of dynamic testing is that it is only as good as the test cases. To be effective, a great deal of effort must go into writing or generating good test cases, and doing so can be very expensive.

Posted in: Articles, Articles


Machine Vision and Smart Cameras: Powerful Tools for Machine Builders

Machine builders in this day and age are part of a fast-growing and rapidly changing industry sector. With vast improvements in commercial off-the-shelf products for measurement and control, as well as falling prices, machine builders can now take advantage of an assortment of powerful tools when implementing their designs, rather than rely on the age-old method of making a custom design for every application.

Posted in: Articles, Imaging, Design processes, Imaging and visualization, Manufacturing equipment and machinery


Enhancing Image Clarity in the SWIR

A chromatic or color-corrected lenses for use in the visible portion of the electromagnetic spectrum have been addressed in literature, textbooks, and industry journals as early as the 18th Century. Many of these accounts by scientists and optical designers detail a method of selecting two dissimilar materials to form an achromatic pair or doublet with the ability to greatly counter image blurring resulting from the dispersive nature of refractive optical elements. Whether these tried and true optical formulae produce equally successful results in wavelengths beyond the visible range warrants further examination.

Posted in: Articles, Imaging, Optics, Glass, Refractory materials


Medical X-Ray Imaging System Improves Patient Diagnosis

For more than 40 years, Italray srl (Florence, Italy) has manufactured radiological equipment for traditional and digital medical applications, as well as computer-assisted systems dedicated to radiological purposes. The company’s solutions — which range from simple mobile x-ray equipment to complete radiology/ fluoroscopy diagnostic installations for traditional and digital radiology applications and angiography — are used in hospitals, universities, private research centers, and nursing homes in Europe and other parts of the world.

Posted in: Application Briefs, Imaging, Imaging and visualization, Diagnosis, Medical equipment and supplies, Suppliers, Radiation


Off-the-shelf Components Upgrade Analog X-ray Equipment

The discovery of X-rays was first reported at the end of 1895 when Wilhelm Conrad Rontgen was conducting experiments with electrostatic charges and cathode ray tubes. In 2008, we have such medical imaging technology as computed tomography (CT), magnetic resonance imaging (MRI), or positron emission topography (PET). It might sound as though x-rays are antiquated. But they’re not.

Posted in: Application Briefs, Imaging, Computer software and hardware, Imaging and visualization, Magnetic resonance imaging (MRI), Diagnosis, Medical equipment and supplies


TFT LCD Display

AZ Displays, Aliso Viejo, CA, has released the PD057VT1, a 5.7-inch digital active matrix TFT panel display. The PD057VT1 display is compatible with computer screen formats and has full Video Graphics Array/VGA (640 × 480 dot) resolution. The display has a “stripe” pixel configuration, a TTL interface, and 262, 144 colors. The module size is 144.0 × 104.6 × 13.0 mm, with a viewing area of 118.4 × 89.6 mm.

Posted in: Products, Imaging


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