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A study was conducted to describe the development of a unidimensional piezoelectric transducer modeling technique that has been extended to laminated structures. Stress was represented by the product of the elastic constant, electric flux density and piezoelectric constant with the particle displacement over the x-direction. The stacked transducer structure electrically connected in parallel was also represented in the study.

A theoretical modeling approach is used for nondestructive evaluation (NDE) imaging of ultrasonic transducer arrays. Multielement piezocomposite and piezopolymer arrays, and hybrid devices with piezocomposite transmitters and piezopolymer receivers are evaluated. The experimental results are comparable with the theoretical results, showing the effectiveness of the device and its methodology. The modified lead titanate platelet composite used for NDE has good transmission sensitivity and flexibility.

A theoretical modeling approach based on a transducer model has been developed for the nondestructive evaluation of flexible ultrasonic transducer arrays. The method uses a comprehensive thickness mode transducer model to optimize the electromechanical transduction response of multilayered transducer structures. Modifications in the existing facet ensemble surface scattering model allow its application in flexible arrays. The modeling approach considers the effects of multiple refections and partial shadowing of surface features.

A computer simulation model of data generation in ultrasonic array nondestructive evaluation imaging reveals the importance of transducer directivity, individual ultrasonic wavelet and wavefield-imaging surface interaction. The model simulates the imaging of a solid medium fatigue crack. The simulations include a study of varying array element spacing and center frequency, considered along with aperture size, defect angle and surface roughness.

'The shortage of alcoholism and drug abuse counselors in the United States is equivalent in significance to the overall nursing staff shortage in medicine, in terms of its impact on [...]

This paper investigates the iron loss that results in a novel topology of switched reluctance (SR) machine which has been developed for application as a starter/generator within the high pressure region of an aero-engine. It will be shown that the machine has a significantly lower loss than that of an equivalent SR machine equipped with a conventional rotor and, thus, a lower operating temperature, which is a critical factor. The iron losses in the cobalt-iron stator and rotor laminations are calculated on a per-element basis using flux density data derived from electric circuit-coupled finite-element analysis. Index Terms--Aircraft power systems, cobalt alloys, finite-element (FE) methods, reluctance machines.

Surveyed 110 military alcohol and drug abuse counselors and 16 clinical supervisors to compare their views of training needs. Results indicated both groups felt improvement was needed in assessment skills and family issues. Supervisors felt counselors needed improvement in affective qualities, basic helping skills and individual helping skills. (JAC)

Examines alcoholism and drug abuse counselors' skills and training needs as determined by experienced clinical supervisors. The results indicate the need for advanced training in a number of clinical competencies: group and family counseling, client assessment, and long-term therapy techniques. (Author)

The addiction treatment field is 'graying.' Consider the results of a University of Georgia national longitudinal study (between 1995 and 2004) of more than 400 privately funded addiction treatment programs. [...]

GOOD TRAINING STARTS AT 'HOME' -- THE TREATMENT FACILITY -- UNDER A SUPERVISOR'S WATCHFUL EYE A lingering memory of last year's summer Olympics was a televised report on what it [...]