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The Cotton Trash Identification System (CTIS) developed at the Southwestern Cotton Ginning Research Laboratory was evaluated for identification and categorization of extraneous matter in cotton. The CTIS bark/grass categorization was evaluated with USDA-Agricultural Marketing Service (AMS) extraneous matter calls assigned by human classers for 210 cotton bale samples. AMS classers assigned extraneous matter calls on four cotton faces of a sample from a given bale of cotton. Scanner acquired images of the same four faces at 400 DPI and 800 DPI resolutions were analyzed to evaluate the CTIS performance. Soft computing techniques were used to identify trash objects in the acquired cotton images (4 in. x 7 in.) and categorize the objects into bark/grass, stick, leaf, and pepper trash categories. The primary goal of the study was to evaluate and calibrate CTIS categorization of extraneous matter using classer extraneous matter calls. CTIS agreed with the classer call 97% of the time when there was a classer extraneous matter call and 43% of the time when there was no classer call. CTIS may find a place as a tool to aid human classers in the classification of cotton by helping to identify extraneous matter. [ABSTRACT FROM AUTHOR]

A method was developed at the Cavendish Laboratory (Cambridge University) to determine the internal displacement characteristics of a polymer rod undergoing classic Taylor impact. Using a layer of lead filings on the central plane of the rod and Digital Speckle Radiography with flash x-rays it was possible to build up a dynamic displacement map. This technique can be used to derive material properties such as yield strength and provide data for model validation. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

This paper describes a simple optical technique for simultaneous photographic recording of high-speed events in stereo, using a translated lens stereoscopic system. An optical wedge is used to refract two spatially separated images together and the result is photographed as a split-frame. The technique is applied to the bulging of a plate on impact by a cylindrical rod. Methods of analysing in-plane movements in each stereoscopic image include use of a grid and a speckle pattern. The different in-plane movements between the two images, owing to perspective differences, can be used to extract topological information. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

The technique of Digital Speckle Radiography (DSR) has been shown to be widely applicable to the field of ballistics through its ability to measure internal displacement fields to a high precision. In a DSR experiment, a flat plane, typically 500 μm thick, of X-ray opaque filings are introduced into the sample during manufacture. Flash X-rays can then be used to image the plane, both before and during an impact event, to produce random speckled images on an X-ray film. Small sub-regions of the images can be tracked relative to each other using a Digital Speckle Photography (DSP) correlation algorithm. This produces a displacement field within the specimen on the seeded plane. By repeating an experiment with identical specimens, but varying the delay of the X-ray exposure, a full time history of the impact event can be obtained. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

Room temperature stress-strain curves were measured for the polymer bonded explosive (PBX) EDC 37 at strain rates between 400 s-1 and 4000 s-1. The material was found to exhibit strong strain rate dependence in this region, the strength increasing linearly with increasing rate. Speckle photography was used to measure the two dimensional surface deformation of the specimens during the test. The behaviour was found to be uniform at most rates, however, the specimens tested at 4000 s-1 showed shear banding. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

The absolute cryogenic radiometer (ACR), an electrical-substitution-based detector, is the most accurate method for measurement of radiant power in the extreme ultraviolet. At the National Institute of Standards and Technology, ACR-based measurements are currently used as standards from the infrared and into the vacuum ultraviolet, however, no radiometric facilities are currently in operation with enough incident power to use an ACR in the extreme-ultraviolet region. Therefore, we have installed transfer optics on an existing beamline to allow the installation of the ACR as an additional endstation. We will describe the current radiometric beamline, the ACR, and the high-throughput beamline, and the transfer-optical system. Finally, we will present the performance of the transfer optics and measurements of the beam profile and incident power of the new endstation. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]