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Mayor Daley of Chicago holds “Viva Kennedy” sign (photograph)
No full textJoe Alvarado, second from left, (?), Mayor Daley of Chicago holds “Viva Kennedy” Sign
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Mayor Daley of the Chicago Daily News is serenade by the American G.I. Forum of Chicago- Senor Daley – Happy Birthday (photograph)
No full textMayor Daley of the Chicago Daily News is serenade by the American G.I. Forum of Chicago- Senor Daley – Happy Birthday
9/11/01 IN MEMORIAM RICE CHORALE Sunday, September 11, 2005 7:00 p.m. Stude Concert Hall
No full textPlaylist: For the Beauty Of The Earth / John Rutter -- The Rose and the Gardener / Eleanor Daley (b. 1955) -- The Awakening / Joseph M. Martin (b. 1959) -- Requiem / John Rutter
Group including Charles Daley senior, Caroline Rose Daley, two unidentified women and one unidentified man having a picnic, Flagstaff Hill, Victoria, 1925 [picture].
No full textTitle devised by cataloguer based on inscriptions.; Part of the collection: C.S. Daley photograph collection.; Inscriptions: "Excursion to Whipstick Scrub, Flagstaff Hill, Oct. 1925; C.D., V.M., Mrs M., Mrs D., Mrs H."--In ink on verso.; Condition: Faded, marks on photo.; Also available in an electronic version via the Internet at: http://nla.gov.au/nla.pic-vn4660839
A method of adaptation between steepest-descent and Newton's algorithm for multichannel active control of tonal noise and vibration
No full textActive control methods have been applied to a number of practical problems in which it is necessary to control a tonal disturbance. For example, the control of engine noise and vibration in vehicles, propeller noise in aircraft and the vibration produced by reciprocating machinery in many industrial systems. In such applications the steepest-descent algorithm has been widely employed, in part due to its robustness to variations in the plant response. This robustness, however, comes at the expense of a potentially slow convergence speed and this may limit the performance in applications where the disturbance is non-stationary. To improve the speed of convergence, an iterative least-squares algorithm can be employed, such as Newton’s algorithm. The convergence of these algorithms is less dependent on the potentially large eigenvalue spread of a multichannel plant matrix and, therefore, can theoretically achieve more rapid convergence. However, these algorithms are significantly less robust to plant response variations and, therefore, their practical performance can be somewhat limited. Generalised algorithms have been presented which combine steepest-descent and Newton’s method in or- der to provide a fixed compromise between convergence and robustness. This paper presents a method of adaptively combining steepest-descent and Newton’s method in order to achieve both rapid convergence and robustness to plant response variations. The two algorithms are combined into a single update equation in which a single mixing parameter facilitates a trade-off between the two algorithms. A method of adapting this parameter to minimise the cost function is presented and the performance of the proposed algorithm is assessed through a series of simulations. The proposed combination algorithm is shown to improve the control performance in the presence of plant response variations compared to both the steepest-descent and Newton’s algorithms
Multivariable control of tonal disturbances using minimization of the maximum error signal through adaptive error signal weighting
No full textIn many multichannel active noise and vibration control systems the controller is adapted to minimize the 2-norm of the error signals. This may, however, lead to a large spatial variance in the residual error. A method of achieving a more uniformly controlled error field using a weighted squared error strategy has previously been proposed, although the presented method of defining the error weighting parameters results in a very slow convergence rate. This convergence rate limitation has been overcome by the minimax algorithm which minimizes, in a least-squares sense, the maximum error signal at each iteration. However, due to the inherent switching in this algorithm, for fast convergence speeds it suffers from significant misadjustment and in a tonal control problem this introduces additional unwanted spectral components. In this paper an alternative method of minimizing the maximum error signal is proposed which uses an adaptive error-weighting matrix that is bounded and so avoids the slow convergence speeds previously reported. It is also shown that the proposed algorithm does not suffer from the same misadjustement problems shown by the minimax algorithm. The details of the proposed method are first outlined and then its performance is compared to the previously proposed methods through a series of time-domain simulations employing measurements of a physical system
An active viscoelastic metamaterial for isolation applications
No full textMetamaterials are of interest due to their ability to produce novel acoustic behaviour beyond that seen in naturally occurring media. Of particular interest is the appearance of band gaps which lead to very high levels of attenuation within narrow frequency ranges. Resonant elements within metamaterials allow band gaps to form within the long wavelength limit at low frequencies where traditional passive isolation solutions suffer poor performance. Hence metamaterials may provide a path to high performance, low frequency isolation. Two metamaterials are presented here. An acoustic material consisting of an array of split hollow spheres is developed, and its performance is validated experimentally. The application of an acoustic/mechanical analogy allows the development of an elastodynamic metamaterial that could be employed as a high performance vibration isolator at low frequencies. A prototype isolator is manufactured, and its performance is measured. The passively occurring band gap is enhanced using an active control architecture. The use of the active control system in conjunction with the natural passive behaviour of the metamaterial enables high levels of isolation across a broad frequency range. An eventual goal of the work is to produce such materials on a small scale, and as such the metamaterials developed are designed for, and produced using, additive layer manufacturing technique
An active viscoelastic metamaterial with enhanced band gap properties
No full textMetamaterials have been the subject of significant interest over the past decade due to their ability to produce novel acoustic behaviour beyond that seen in naturally occurring media. Of particular interest is the appearance of band gaps which lead to very high levels of attenuation across the material within narrow frequency ranges. Unlike traditional periodic materials which have been employed at high frequencies, the resonant elements within metamaterials allow band gaps to form within the long wavelength limit. It is at low frequencies where it is most difficult to design satisfactory passive isolation solutions, and hence metamaterials may provide a useful path to high performance, low frequency isolation. A locally resonant, periodic metamaterial is presented that could be employed as a high performance vibration isolator at low frequencies. The passively occurring band gap is enhanced using an active control architecture. The use of the active control system in conjunction with the natural passive behaviour of the metamaterial enables high levels of isolation across a broad frequency range. An eventual goal of the work is to produce such materials on a small scale, and as such the metamaterial developed has been designed for, and produced using, additive layer manufacturing techniques
Parent Training for ADHD in Preschool Children
No full textThere is a need for effective psychosocial interventions for young children with ADHD. Evidence exists to support the efficacy of three current parenting programs in this area: the New Forest Parent Training (NFPT) program, the Positive Parenting Program (PPP), and the Incredible Years (IY) program. With regard to the NFPT program, there is strong evidence demonstrating its effectiveness for preschool children with ADHD; however, the evidence supporting the PPP in this population is less strong, and the effectiveness of the IY program has only been demonstrated in children with conduct problems and comorbid ADHD
Mickey Ibarra with Commerce Secretary Daley
No full textColor photograph of Mickey Ibarra with Secretary of Commerce William M. Daley (second to right), and Phillip Singerman, Assistant Secretary for Economic Development at the US Department of Commerce, after speaking
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