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Exterior problem

So the probability current is to be conservative for the three consecutive situations state 2, transition 2 — 1, and state 1. Furthermore, it must correspond to a solution of the Dirac equation, which satisfies the exterior problem for the periods that concern the states 2 and 1. [Pg.42]

In our elementary presentation of the transitions, we will not take into account the small correction to each of these levels called the Lamb shift. So, we adopt here for E and E2 the values given for each state 1 and 2 by the bare solutions of the Dirac equation in the exterior problem. [Pg.43]

Now let us consider the exterior problem about mass exchange between a spherical drop (bubble) of radius a and a translational Stokes flow with limiting diffusion resistance of the continuous phase. [Pg.170]

In the linearized theory with bias field of magnitude, a typical magnetoacoustic coupling coefficient (usually a small parameter) is defined by when and P2 are typical components of and This causes a lowering of the acoustic speed [9] while piezoelectricity expressed in terms of electric fields causes an increase in the acoustic speed [1]. It must also be noted that in a magnetic case one always has to solve interior and exterior problems matched by the boundary conditions (2.3)1 thus always expressed in terms of jumps, since there does... [Pg.124]

Using these procedures it is always possible to generate smooth internal divisions. Therefore they offer the advantage of preventing the extension of the exterior boundary discontinuities to the inside of the problem domain. [Pg.195]

In this subsection we analyse an optimal control problem. The exterior forces f,g) are chosen to minimize the cost functional... [Pg.192]

Here n is a unit exterior vector to F. As it was indicated in the previous section, in the domain fig the following problem can be solved. [Pg.258]

In this subsection we prove the solvability of the elastoplastic problem for a plate having a nonsmooth boundary. A solution of the problem will satisfy all boundary conditions both at the exterior boundary and at the crack faces. [Pg.336]

Fig. 2. Problems in wetting A, Hquids that wet the exterior before displacing gas from pores leave gas trapped in the submerged clump B, fully wetted clumps of buoyant particles do not sink C, nonwetting Hquids do not penetrate and displace gas from pores, so clump remains buoyant and caimot submerge and D, foam produced from air is drawn under the surface, sheared into small bubbles, and stabilized by the wetting agent. Fig. 2. Problems in wetting A, Hquids that wet the exterior before displacing gas from pores leave gas trapped in the submerged clump B, fully wetted clumps of buoyant particles do not sink C, nonwetting Hquids do not penetrate and displace gas from pores, so clump remains buoyant and caimot submerge and D, foam produced from air is drawn under the surface, sheared into small bubbles, and stabilized by the wetting agent.
Vibration is both a cause of problems and an effect of equipment problems. The potential destructive force of an out-of-balance load has led to setting lower shutdown limits on the magnitude of vibration than other rotating equipment. Flexible connections for process and utility lines become a must so these vibration problems are not transmitted to connected equipment. Flexible hoses with liners having concentric convolutions (bellows type) avoid the sharp points inherent with spiral metallic liners. By avoiding the sharp point the liner is less likely to cut the exterior covering. [Pg.39]

Laminated beams (glulam), parallam (or LSL) and fingerjoints a flat pressed multilayer wood beam, thiek wood planks constituting the layers, used for structural exterior applications and bonded with PRF (phenol-resorcinol-formaldehyde) cold-setting resins, or MUF cold-setting resins, or even with certain types of polurethanes (although the use of these latter ones is only established in one country and can show creep and temperature-induced creep problems). The indi-... [Pg.1045]

Outdoor air is generally less polluted than the system return air. However, problems with reentry of previously exhausted air occur as a result of improperly located exhaust and intake vents or periodic changes in wind conditions. Other outdoor contamination problems include contaminants from other industrial sources, power plants, motor vehicle exhaust, and dust, asphalt vapors, and solvents from construction or renovation. Also, heat gains and losses through the building envelope due to heat conduction through exterior walls, floor, and roof, and due to solar radiation and infiltration, can be attributed to effects from external sources. [Pg.418]

Although transformers suitable for other industrial installations are generally suitable for producing applications, certain options may be desirable— primarily due to environmental considerations. At locations subject to harsh environmental conditions, and particularly at locations subject to washdown with high-pressure hoses, non-ventilated enclosures are desirable, if not necessary. Likewise, at locations subjected to salt water and salt-laden air, it often is desirable to specify copper windings and lead wires. Most manufacturers provide standard units with aluminum windings and lead wires. Even if aluminum coils are used, it is almost always desirable to require stranded copper lead wires. This will lessen corrosion and loose terminal problems when transformers arc interconnected to the facility electrical system with copper conductors. If the transformers are to be installed outdoors in corrosive environments, cases should be of corrosion-resistant material (e.g., stainless steel) or be provided with an exterior coating suitable for the location. [Pg.541]

Wood is painted in order to preserve from decay, to minimize changes in moisture content that lead to distortion, and for decoration. It is a waste of time and effort to apply expensive paints or stains to exterior wood not previously treated with preservative. Preservatives are designed to penetrate the timber to protect against microorganisms and insect attack. Modern preservatives can be over-coated with paint without problems. [Pg.133]

Leaks in process vessels and devices such as valves are a serious problem in many industries. A variation of vibration monitoring and analysis can be used to detect leakage and isolate its source. Leak-detection systems use an accelerometer attached to the exterior of a process pipe. This allows the vibration profile to be monitored in order to detect the unique frequencies generated by flow or leakage. [Pg.665]

Nylon 11 Nylon 11 is a hard abrasion-resistant, scuff-resistant coating. When correctly formulated and applied, it can be used for exterior application. It has good resistance to solvents and to a range of alkalis and salt solutions up to 80°C. If water quenched, the coating has excellent impact strength. However, Nylon 11 is crystalline and pull-back from sharp edges can be a problem. It is therefore essential that metal work is well radiused. [Pg.753]

A problem associated with plant inspection is the coupling of the probe to the metal under examination. The exterior surface of plant can be covered in rust which causes problems in coupling the probe to the metal and results in spurious and inaccurate results. Often operators move the probe to an area where adequate coupling is obtained, circumventing the real objective of the measurement. It is often impossible to obtain any coupling on severely corroded steel surfaces, e.g. the interior of flash distjllation plant chambers. [Pg.1144]

Neal and Nader [260] considered diffusion in homogeneous isotropic medium composed of randomly placed impermeable spherical particles. They solved steady-state diffusion problems in a unit cell consisting of a spherical particle placed in a concentric shell and the exterior of the unit cell modeled as a homogeneous media characterized by one parameter, the porosity. By equating the fluxes in the unit cell and at the exterior and applying the definition of porosity, they obtained... [Pg.572]

Magnesium oxychloride cements are widely used for the fabrication of floors. They find application for this purpose because of their attractive appearance, which resembles marble, and also because of their acoustic and elastic properties and their resistance to the accumulation of static charge. They have also been used for plastering walls, both interior and exterior for exterior walls the cement often includes embedded stone aggregate (Sorrell Armstrong, 1976). However, there have been problems with this latter application, since the base cement has been found to be dimensionally unstable and, in certain circumstances, to release corrosive solutions and show poor weather resistance. [Pg.290]

Equation (1.84) form Dirichlet s boundary value problem, which can be either exterior or internal one. Fig. 1.8a, and it has several important applications in the theory of the gravitational field of the earth. It is worth to notice that in accordance with Equation (1.83) we can say that along any direction tangential to the boundary surface, the component of the field is also known, since = dU/dt. Consequently, the boundary value problem can be written in terms of the field as... [Pg.29]

Boundary value problem can be either the exterior or internal one, and each boundary condition is equally applied to both cases. [Pg.33]

Weep holes are used to drain water from the block cores into the subslab area when surface waterproofing barriers fail. Such a connection between the exterior and interior subslab areas is an obvious channel for radon entry, allowing soil gas to pass from the subslab to the interior of the block wall. Openings from the subslab into the block wall would also make it difficult to apply active SSD at a later date. If the block tops are sealed and the interior of the block wall is sealed, then weep holes would be much less of a problem as radon entry points or as barriers to SSD. [Pg.1275]


See other pages where Exterior problem is mentioned: [Pg.42]    [Pg.184]    [Pg.132]    [Pg.42]    [Pg.184]    [Pg.132]    [Pg.93]    [Pg.361]    [Pg.426]    [Pg.584]    [Pg.334]    [Pg.195]    [Pg.321]    [Pg.338]    [Pg.351]    [Pg.354]    [Pg.355]    [Pg.347]    [Pg.1158]    [Pg.204]    [Pg.942]    [Pg.100]    [Pg.440]    [Pg.1294]    [Pg.58]    [Pg.681]    [Pg.74]    [Pg.92]    [Pg.516]    [Pg.149]    [Pg.1275]   


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