Local instability

The passive state of a metal can, under certain circumstances, be prone to localized instabilities. Most investigated is the case of localized dissolution events on oxide-passivated surfaces [51, 106, 107, 108, 109, 110, ill, 112, 113, 114, 115, 116, 117 and 118]. The essence of localized corrosion is that distinct anodic sites on the surface can be identified where the metal oxidation reaction (e.g. Fe —> Fe + 2e ) dominates, surrounded by a cathodic zone where the reduction reaction takes place (e.g. 2Fi + 2e —> Fi2). The result is the fonnation of an active pit in the metal, an example of which is illustrated in figure C2.8.6(a) and (b). 

Scaling analysis has also been applied to quasi-2D deposits in thin layer cells where the images were obtained by optical microscopy. These studies focus on length scales up to hundreds of micrometers, and find a clear non-local instability, but also report KPZ like behavior on smaller scales [79-81],... 

Slenderness considerations are of particular importance to the ductility of structural steel members, Steel, as compared to other building materials used in blast design, is considerably thinner, both in terms of the overall structure anc the components of a typical member cross section. As a result, the effect of ovcratl and local instability upon the ultimate capacity is an important consideration. Width-thickness provisions must be applied not only to the extent that a full plastic capacity can be achieved, but to the extent that higher ductility ratios can also be safely reached. The width-thickness ratios, from Table 8-1 of Seismic Provisions for Structural Steel Buildings (AISC 1992) are used for this purpose. 

Koch, W. (1985). Local instability characteristics and frequency determination of self excited wake flow. J. Sound and vib., 99, 53-83. 

In this section, we study the singular values of an many-dimensional oscillator system, as the first step toward the elucidation of the dynamical origin of ordered motions, and show a clear evidence of coexistence of qualitatively different local instabilities along a trajectory, which enables us to accurately determine lifetimes of ordered motions. 

In this section, we have applied our novel method to the detecting ordered motions with the linear increase of singular values of stability matrixes. From the crossover times of local instabilities that change from linear to exponential increases, lifetimes of... 

A common simplifying assumption is that matter is distributed uniformly throughout the universe, subject to gravitational interaction. On this basis Newton could argue that in a universe of limited size all matter would eventually clump together in a central mass. Dynamic equilibrium, as observed, can only develop in an infinite universe. The resultant gravitational field should vanish everywhere, but local instabilities can give rise to the formation of stars and solar systems. The metric of such a system is clearly Euclidean. 

The other type of buckling is a result of local instability that may or may not result in a change in the axis of the cylinder. This type is known as local buckling, and the stability against local buckling is dependent on t/R ratios. 

An underground mall in Qingdao Soil nailing wall Open excavation method Flybrid support 12 m Local instability Inadequate exploration 0 0.2 million... 

Local instability Overall instability Retaining structure leakage Supporting instability Piping erosion Soil landslide inside the pit Pile broken Surrounding environment destruction... 

Table 4. Cause distribution list of local instability. ...

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