We studied the effect of low-pass band filters on the dynamics of a nonisothermal autocatalator as seen through feedback on a system parameter. Filters were created by selecting Fourier coefficients for the modes in the pass band according to a uniform distribution. Numerical simulations over many realizations of feedback were compared to theoretical predictions for the feedback size as a funct...

The ecliptic elongation of the moon with respect to the sun does not show uniform distribution on the birth dates of the 704 soccer players selected for the 1998 World Cup. However, a uniform distribution is expected on astronomical grounds. The World Cup players show a very pronounced tendency (p = 0.00001) to be born on days when the sun and moon are in adjacent zodiacal signs.

Conventional metals are routinely hardened by grain refinement or by cold working with the expense of their ductility. Recent nanostructuring strategies have attempted to evade this strength versus ductility trade-off, but the paradox persists. It has never been possible to combine the strength reachable in nanocrystalline metals with the large uniform tensile elongation characteristic of coars...

We consider a sequence of independent and identicaly distributed (iid) random variables with absolutely continuous distribution function F(x) and probability density function (pdf) f(x). Let Rnl be the largest observation after observing nth record and R(ns) be the smallest observation after observing the nth record. Then we say Wnr = Rnl− R(ns), n > 1, as the nth record range. We will c...

The influence of intermetallic particles and hydrides on the total and local ductility as well as on the fracture mechanism in Zr-2.5Nb and Zr-1Nb-1.3Sn-0.4Fe alloys was studied by the methods of acoustic emission (AE). Based on measurements of maximum (peak) values of AE amplitudes depending on secondary phase sue and distribution two alternative mechanisms were established of loss of flow sta...

A new optimization concept is introduced which involves the optimization of non-linear planar shear buildings by using gradients based on equivalent linear structures, instead of the traditional practice of calculating the gradients from the non-linear objective function. The optimization problem is formulated as an equivalent linear system of equations in which a target fundamental eigenfreque...

zipper braced frames are an innovative bracing system for steel structures. conventional inverted-v-braced frames exhibit a design problem arising from the unbalanced vertical force generated by the lower story braces when one of them buckles. this adverse effect can be mitigated by adding zipper columns or vertical members connecting the intersection points of the braces above the first floor....

Knowledge of the yield point and ductility of a structure is important in seismic design. The yield point of an assembly is defined as a point where it begins to plastically deform, while ductility describes its ability to yield without substantial reduction in strength. These parameters can be determined from the analysis of the load-deformation curves resulting from destructive tests. To date...

This paper establishes the optimal thickness of TiN ceramic coating on surface Mg-Ca-Zn alloy using optical and scanning microscopy methods. X-ray diffraction analysis tests its mechanical properties showed that deposition with a not less than 1 μm causes uniform distribution phase over magnesium surface. The also contributes to simultaneous increases in yield strength, tensile ductility microh...