845 research outputs found
The Use of Continuous Wave Ultrasonic Spectroscopy for Adhesive-Bond Evaluation
The program to be described here was initiated during the past year at the Air Force Materials Laboratory. The problem of deterMining adhesive bond strength was undertaken with a rather bruteforce approach of simply collecting the best possible data, utilizing existing ultrasonic plane-wave theory for layed structures to calculate ultrasonic spectra, and then attempting the inversion of the d~ta to obtain the acoustic properties of the materlal or structure. An empirical correlation of these acoustic properties with the destructively measured bond strength is planned
Detection of Radial Bolt-Hole Cracks Using Sampled CW Ultrasonic Doppler-Shift Techniques
Recently there has been considerable interest in detecting radial cracks under fasteners in the wings of C-5A aircraft. Generally, detection is accomplished using the pulse-echo method, reflections from cracks being detected in real time. In the present study, cracks are detected by observing the ·Doppler-shifted frequency. A sample having a radial crack is mounted on a rotating platform in a water bath. A focused transducer transmits a tone burst such that only the shear mode propagates tangential to the hole in the metal. This transducer receives a Doppler-shifted reflected signal whenever a moving crack is in the field of view of the incident beam. The received signal is heterodyned, filtered, and displayed on a low-frequency spectrum analyzer. Merits and limitations of the technique are discussed
Radioactive particulate release associated with the DOT specification 6M container under hypothetical accident conditions
A testing program was conducted to determine the leakage of depleted uranium dioxide powder (DUO) from the inner containment components of the US Department of Transportation's (DOT) specification 6M container under hypothetical accident conditions. Depleted uranium dioxide was selected as a surrogate for plutonium oxide because of the similarities in the powder characteristics, density and particle size, and because of the special handling and special facilities required for plutonium oxide. The DUO was packaged inside food pack cans in three different configurations inside the 2R vessel of the 6M container. The amount of DUO powder leakage ranged from none detectable (<2 x 10/sup -7/ g) to a high of 1 x 10/sup -3/ g. The combination of gravity, vibration and pressure produced the highest leakage of DUO. Containers that had hermetic seals (leak rates <6 x 10/sup -4/ atm cc/min) did not leak any detectable amount (<2 x 10/sup -7/ g) of DUO under the test conditions. Impact forces had no effect on the leakage of particles with the packaging configurations used. 23 refs., 24 figs., 3 tabs
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Geologic Review of Proposed Dallas -Fort Worth Area Site for the Superconducting Super Collider (SSC)
In June 1987, the Texas National Research Laboratory Commission tasked the Bureau of Economic Geology at The University of Texas at Austin with reviewing and providing a brief report on the geology of the proposed site for the Superconducting Super Collider (SSC) in the Dallas-Fort Worth area. Additionally, they requested a surface geologic map of the site. An informal task force was assembled for this purpose, comprising Jay A. Raney (Coordinator and Structural Geology) from the Bureau of Economic Geology, Peter M. Allen (Environmental Geology and Stratigraphy) from Baylor University, Donald F. Reaser (Structural Geology and Stratigraphy) from The University of Texas at Arlington, and Edward W. Collins (Structural Geology) from the Bureau of Economic Geology. This report by the task force provides an explanatory note for the geologic map (Plate 1) of the proposed site near Waxahachie, Texas.Bureau of Economic Geolog
State Responses to the Tax Cuts and Jobs Act: An Analysis from Indiana and Missouri
This Article, authored by lawyers from the Indiana Department of Revenue and Missouri Department of Revenue, is intended to address, and hopefully add clarity to, the complexities of state taxation under the Tax Cuts and Jobs Act of 2017 (“TCJA”). After a brief historical and general overview of the TCJA, this Article focuses on seven distinct topics within the TCJA from a state perspective. These topics are: (1) Business Assets Expensing; (2) the TCJA’s treatment of 529 Accounts; (3) the 30% Business Interest Limitation; (4) the Transition Tax (also referred to as “Deemed Repatriation”); (5) GILTI, or Global Intangible Low-Taxed Income; (6) the elimination of the Personal and Dependency Exemption Deductions; and (7) the Qualified Business Income Deduction. For each topic, this Article gives an overview of the associated TCJA provisions, addresses some responses of the states to these provisions, and provides opportunity for discussion of possible or actual responses by Indiana and/or Missouri
Limitations for change detection in multiple Gabor targets
We investigate the limitations on the ability to detect when a target has changed, using Gabor targets as simple quantifiable stimuli. Using a partial report technique to equalise response variables, we show that the log of the Weber fraction for detecting a spatial frequency change is proportional to the log of the number of targets, with a set-size effect that is greater than that reported for visual search. This is not a simple perceptual limitation, because pre-cueing a single target out of four restores performance to the level found when only one target is present. It is argued that the primary limitation on performance is the division of attention across multiple targets, rather than decay within visual memory. However in a simplified change detection experiment without cueing, where only one target of the set changed, not only was the set size effect still larger, but it was greater at 2000 msec ISI than at 250 msec ISI, indicating a possible memory component. The steepness of the set size effects obtained suggests that even moderate complexity of a stimulus in terms of number of component objects can overload attentional processes, suggesting a possible low-level mechanism for change blindness
Airborne Visible/Infrared Imaging Spectrometer (AVIRIS): Sensor improvements for 1994 and 1995
AVIRIS is a NASA-sponsored Earth-remote-sensing imaging spectrometer designed, built and operated by the Jet Propulsion Laboratory (JPL). While AVIRIS has been operational since 1989, major improvements have been completed in most of the sensor subsystems during the winter maintenance cycles. As a consequence of these efforts, the capabilities of AVIRIS to reliably acquire and deliver consistently high quality, calibrated imaging spectrometer data continue to improve annually, significantly over those in 1989. Improvements to AVIRIS prior to 1994 have been described previously. This paper details recent and planned improvements to AVIRIS in the sensor task
Couple-based interventions in the treatment of adult anorexia nervosa: A brief case example of UCAN.
Adult anorexia nervosa (AN) is a serious and often fatal illness that significantly erodes quality of life for both the patient and loved ones. Treatment of adults with AN has focused largely on individual therapy, with recent findings suggesting that improvement is limited and dropout rates are high. In an effort to improve treatment response, we developed a couple-based intervention, Uniting Couples in the treatment of Anorexia Nervosa (UCAN) as an adjunct treatment to standard multidisciplinary care. UCAN leverages the support of a partner and the relationship in treatment by decreasing avoidance around AN, teaching the couple how to effectively address the eating disorder, and helping to foster a more satisfying relationship. This paper presents a case study of a couple who completed UCAN, “Laura and Steve”, including their experiences in treatment and outcome measures at pretest, posttest, and three-month follow-up. Laura showed clinically significant change on the Restraint subscale of the EDE at follow-up, and both partners showed clinically significant improvements in relationship satisfaction, as well as on self-reported and observed communication. Both partners reported very high satisfaction with the treatment. A discussion of therapists' experiences in delivering UCAN is provided, including common challenges for therapists with primarily a couple therapy or an individual CBT for eating disorders background, as well as important factors for therapists to consider in order to optimally leverage the benefits of including partners in treatment for AN
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