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Catastrophe static

In this chapter we shall show how the observed phenomena may be explained by means of elementary catastrophe theory. In principle, the discussion will be confined to examination of non-chemical systems. However, some of the discussed problems, such as a stability of soap films, a phase transition in the liquid-vapour system, diffraction phenomena or even non-linear recurrent equations, are closely related to chemical problems. This topic will be dealt with in some detail in the last section. The discussion of catastrophes (static and dynamic) occurring in chemical systems is postponed to Chapters 5, 6 these will be preceded by Chapter 4, where the elements of chemical kinetics necessary for our purposes will be discussed. [Pg.77]

In Section 1.3 we described the systems in which qualitative and discontinuous changes of state, that is catastrophes, could be observed at a continuous variation in control parameters. The catastrophes occurring in some systems were discussed in terms of elementary catastrophe theory in Sections 3.2-3.6. The discussion was confined to non-chemical systems such a classification (as we shall see later) being rather artificial. Catastrophes (static and dynamic) occurring in chemical systems will be described in Chapters 5, 6. [Pg.122]

As with any analytical method, the ability to extract semiquantitative or quantitative information is the ultimate challenge. Generally, static SIMS is not used in this mode, but one application where static SIMS has been used successfully to provide quantitative data is in the accurate determination of the coverage of fluropolymer lubricants. These compounds provide the lubrication for Winchester-type hard disks and are direaly related to ultimate performance. If the lubricant is either too thick or too thin, catastrophic head crashes can occur. [Pg.555]

The effect of ozone is complicated in so far as its effect is largely at or near the surface and is of greatest consequence in lightly stressed rubbers. Cracks are formed with an axis perpendicular to the applied stress and the number of cracks increases with the extent of stress. The greatest effect occurs when there are only a few cracks which grow in size without the interference of neighbouring cracks and this may lead to catastrophic failure. Under static conditions of service the use of hydrocarbon waxes which bloom to the surface because of their crystalline nature give some protection but where dynamic conditions are encountered the saturated hydrocarbon waxes are usually used in conjunction with an antiozonant. To date the most effective of these are secondary alkyl-aryl-p-phenylenediamines such as /V-isopropyl-jV-phenyl-p-phenylenediamine (IPPD). [Pg.288]

From the temporal scale of adverse effects we come to a consideration of recovery. Recovery is the rate and extent of return of a population or community to a condition that existed before the introduction of a stressor. Because ecosystems are dynamic and even under natural conditions are constantly changing in response to changes in the physical environment (weather, natural catastrophes, etc.) or other factors, it is unrealistic to expect that a system will remain static at some level or return to exactly the same state that it was before it was disturbed. Thus the attributes of a recovered system must be carefully defined. Examples might include productivity declines in an eutrophic system, re-establishment of a species at a particular density, species recolonization of a damaged habitat, or the restoration of health of diseased organisms. [Pg.515]

Note that the energy is the dot product of the induced dipole and the static field, not the total field. Without a static field, there are no induced dipoles. Induced dipoles alone do not interact strongly enough to overcome the polarization energy it takes to create them (except when they are close enough to polarize catastrophically). [Pg.93]

Backup and restore applies to the application code, the configuration, and the static and dynamic data. The objective is to be able to recover the system following a crash or other catastrophic event. [Pg.537]

Fracture process in multidirectional composite laminates subjected to in-plane static or fatigue tensile loading involves sequential accumulation of damage in the form of matrix cracks that appear parallel to the fibres in the off-axis plies, edge delamination and local delamination long before catastrophic failure. These resin dominated failure modes significantly reduce the laminate stiffness and are detrimental to its strength. [Pg.456]

The problem of dependence of the type of stationary points and their stability on control parameters c is thus reduced for systems (1.8) to the investigation of a dependence of the type of critical points of a potential function V and their stability on these parameters. The above mentioned problems are, as already mentioned, the subject of elementary catastrophe theory. Owing to the condition (1.9), catastrophes of this type will be referred to as static. A catastrophe will be defined as a change in a set of critical points of a function V occurring on a continuous change of parameters c. As will be shown later, the condition for occurrence of a catastrophe is expressed in terms of second derivatives of a function V, 82V/8il/idil/j. [Pg.11]

Let us now turn to a brief discussion of the examination of systems (1.6) by catastrophe theory techniques. To begin with, in systems (1.6) such static catastrophes may occur for which the condition (1.9) is satisfied. It follows from equations (1.6), (1.9) that in the stationary state of an autonomous system the condition... [Pg.12]

A typical example of a static catastrophe in the system (1.6) is the change in number of solutions of the system of equations (1.11) on varying c (a catastrophe of this type is called bifurcation). The condition of occurrence of a catastrophe of this type is expressed in terms of derivatives of functions U dfi/fyj. [Pg.12]

When the condition (1.9) is not met in (1.6), we deal with dynamical catastrophes. In some cases, for example for the so-called Hopf bifurcation, dynamical catastrophes may be examined by static methods of elementary catastrophe theory or singularity theory (Chapter 5). General dynamical catastrophes, taking place in autonomous systems, are dealt with by generalized catastrophe theory and bifurcation theory (having numerous common points). Some information on general dynamical catastrophes will be provided in Chapter 5. [Pg.12]

As explained in Section 1.2, the simplest field of applications of catastrophe theory are gradient systems (1.8). In the case of gradient systems, static catastrophes obeying the condition (1.9) can be studied by the methods of elementary catastrophe theory. Let us recall that a fundamental task of elementary catastrophe theory is the determination how properties of a set of critical points of potential function K(x c) depend on control parameters c. In other words, the problem involves an examination in what way properties of a set of critical points (denoted as M and called the... [Pg.27]

When a catastrophe occurs in a dynamical system, two cases are possible. In the first case, a static catastrophe, the only stable states of the system are stationary points in the case of dynamical catastrophes, stable non-stationary solutions, for example limit cycles, appear. [Pg.161]

The message from Figure 8 is that static lamellae are stable to small disturbances until a critical capillary pressure is attained then coalescence is catastrophic. In porous media, the liquid saturation, absolute permeability, and surface tension control this critical capillary pressure through the Leverett J-function (75). Of course, static lamellae may coalesce at lower capillary pressures, if they are subjected to large disturbances. Figure 8 also reveals that static lamellae in equilibrium with the imposed capillary pressure are amazingly thin. [Pg.140]

ABSTRACT In order to analyze the law of airflow catastrophic of side branches induced by gas pressure in upward ventilation after dynamic of outburst disappearing, one dimensional unsteady-state flow momentum equation of gas flow is established. Combined with circuit airflow pressure balance equation, this equation is used in static and dynamic analysis on airflow catastrophic of side branches induced by gas pressure in upward ventilation. The research results show that gas pressure is produced in upward ventilated roadway when gas flowed by when the gas pressure is great enough, the air flow in side branches reverses. Whether the air flow in side branches reverse is affected by their own length and initial velocity. In order to prevent the air flow reversal in the side branches, it is necessary keep the fan normal operating, and avoids adding resistance in external system. The research results may be of important theoretical and practical significance for outburst accident rescue as well as effective prevention of the occurrence of secondary accidents. [Pg.191]

Li, X.B. Zuo, YJ. Ma, C D. 2005. Failure Criterion of Strain Energy Density and Catastrophe Theory Analysis of Rock Subjected to Static-dynamic Coupling Loading. Chinese Journal of Rock Mechanics and Engineering 24(16) 2814-2824. [Pg.1002]

FMEAID9 Port side Pitot Statics blocked (full or partial) or leaking Catastrophic Extremely Remote Not a system failure, but an event caused by insects/bird strike strike... [Pg.354]

Comparison with standby Altitude display EGPWS alert Pilots may believe misleading instrument Catastrophic 2x10-2 2 pilots, each having a general omission error probability of 1 X 10-2. Refer Table 10.1 TBD - To be compiled Note that one primary display receives pitot static data from same source as the standby display, so ensure pilots are able to diagnose correctly. Open... [Pg.355]

The threshold for slow crack growth in a HDPE occurs at Ki = 0.2 MPa Above this threshold, log(du/dr) under static load increases linearfy with logJiTi until catastrophic fracture occurs at Kic 1.6 MPa m . Specific values of do/dt are 1 nm s" at 0.4 MPa m - and 40 nm s at 1.0 MPa m -. Assuming that HDPE contains defects equivalent to 100 (im cracks, and that Y = 1.15... [Pg.236]


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