A Simple Method of Matric Structural Analysis, Part VI--Bending of Plates of Arbitrary Shape and Thickness Under Arbitrary Normal Loading

1962 ◽  
Vol 29 (3) ◽  
pp. 306-310
Author(s):  
BERTRAM KLEIN
Author(s):  
George T. Lountos ◽  
Scott Cherry ◽  
Joseph E. Tropea ◽  
David S. Waugh

4-Nitrophenyl phosphate (p-nitrophenyl phosphate, pNPP) is widely used as a small molecule phosphotyrosine-like substrate in activity assays for protein tyrosine phosphatases. It is a colorless substrate that upon hydrolysis is converted to a yellow 4-nitrophenolate ion that can be monitored by absorbance at 405 nm. Therefore, the pNPP assay has been widely adopted as a quick and simple method to assess phosphatase activity and is also commonly used in assays to screen for inhibitors. Here, the first crystal structure is presented of a dual-specificity phosphatase, human dual-specificity phosphatase 22 (DUSP22), in complex with pNPP. The structure illuminates the molecular basis for substrate binding and may also facilitate the structure-assisted development of DUSP22 inhibitors.


Author(s):  
M.A.A. Khattab ◽  
D.J. Burns ◽  
R.J. Pick ◽  
J.C. Thompson

In this paper, techniques are developed to handle the integrable singularities of the integral proposed by Burns and Oore for the estimation of opening mode stress intensity factors for embedded planar defects of arbitrary shape. The hybrid numerical-analytical integration techniques developed consider separately two crack front zones and one interior zone of the crack surface. Parameters are established for the sizing of the integration elements within each zone. Studies of elliptical defects with aspect ratios between 1 and 10 demonstrate the accuracy and efficiency of this procedure for computing opening mode stress intensity factors. A simple method which compensates for the quadrature error associated with computationally inexpensive, coarse grids is outlined.


1993 ◽  
Vol 115 (4) ◽  
pp. 384-390 ◽  
Author(s):  
A. D. Pierce

A generalization of the Donnell model for a thin shell of arbitrary shape, and with position-dependent elastic and geometric properties, is used to formulate a wave theory for quasi-straight-crested waves of constant frequency propagating over the shell’s surface. The principal restriction on the theory is that the wavenumber components must be large compared with the two principal curvatures. A simple method for including fluid loading in the model yields a finite local specific radiation impedance even when the waves on the surface are moving with the fluid’s sound speed. The overall model is then used to derive a general dispersion relation which connects frequency and wavenumber components for the fundamental waves of the fluid-shell system.


1993 ◽  
Vol 20 (2) ◽  
pp. 201-209
Author(s):  
Eugene J. O'Brien ◽  
Robert E. Loov

A simple method is proposed as a substitute for the usual process of factoring loads, performing a linear elastic analysis, and determining an envelope of the results. The method is based on statistical principles, but only a minimum knowledge of statistics is required for its use. It involves conventional structural analysis followed by some processing of the results which could readily be incorporated into existing computer programs.The practice of performing two-dimensional analyses on parts of three-dimensional structures is possible with the proposed approach. The implications are clarified and the necessary statistical parameters are derived.Deterministically derived design envelopes represent all the extremes of loading that can reasonably be considered. The envelopes found by the new method not only reflect loading variations but also consider their relative probabilities of occurrence so that excursions beyond the envelope are expected to be equally infrequent along the entire length of the structure. Inconsistencies inherent in the conventional approach are highlighted by comparison with the proposed method for a number of examples. Key words: probabilistic, safety, load, imposed load, load effect envelope, building.


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