The second approach

This paper compares experimental data for aluminium and steel specimens with two methods of solving the forward problem in the thin-skin regime. The first approach is a 3D Finite Element / Boundary Integral Element method (TRIFOU) developed by EDF/RD Division (France). The second approach is specialised for the treatment of surface cracks in the thin-skin regime developed by the University of Surrey (England). In the thin-skin regime, the electromagnetic skin-depth is small compared with the depth of the crack. Such conditions are common in tests on steels and sometimes on aluminium. 

The second approach - creation of systems for non-destructive testing quality assurance in compliance with ISO standards 9000 series - considers the quality system as an assembly of organisational strueture, procedures, processes and resources necessary for overall quality management at the laboratory. This approach requires methodieal development. 

The solution Xh(t) of the linearized equations of motion can be solved by standard NM techniques or, alternatively, by explicit integration. We have experimented with both and found the second approach to be far more efficient and to work equally well. Its handling of the random force discretization is also more straightforward (see below). For completeness, we describe both approaches here. 

Unsaturated Polyesters. There are two approaches used to provide flame retardancy to unsaturated polyesters. These materials can be made flame resistant by incorporating halogen when made, or by adding some organic halogen compound when cured. In either case a synergist is needed. The second approach involves the addition of a hydrated filler. At least an equal amount of filler is used. 

Processes for HDPE with Broad MWD. Synthesis of HDPE with a relatively high molecular weight and a very broad MWD (broader than that of HDPE prepared with chromium oxide catalysts) can be achieved by two separate approaches. The first is to use mixed catalysts containing two types of active centers with widely different properties (50—55) the second is to employ two or more polymerization reactors in a series. In the second approach, polymerization conditions in each reactor are set drastically differendy in order to produce, within each polymer particle, an essential mixture of macromolecules with vasdy different molecular weights. Special plants, both slurry and gas-phase, can produce such resins (74,91—94). 

The second approach, changing the environment, is a widely used, practical method of preventing corrosion. In aqueous systems, there are three ways to effect a change in environment to inhibit corrosion (/) form a protective film of calcium carbonate on the metal surface using the natural calcium and alkalinity in the water, (2) remove the corrosive oxygen from the water, either by mechanical or chemical deaeration, and (3) add corrosion inhibitors. 

The truncation error of this approach is Aa." (Ref. 106). The second approach uses the average of the transport coefficients on either side. 

The second approach to characterize wetting considers the abihty of the fluid to penetrate a powder bed. It involves the measurement of the extent and rate of fluid rise by capillaiy suction into a column of powder, better known as the Washburn test. Considering the powder to consist of capillaries of radius R, the equilibrium height of rise... 

In the second approach, the reconcihation is done sequentially from module to module within the unit under stuc. This is done typically following the primary direction of material flow. This approach reconciles the measurements for each module in turn, progressing through the entire unit under study. Consequently, the reconciled measurements from the first module are used in the reconcihation of... 

The second approach, that of surface coating, is more difficult, and that means more expensive. But it is often worth it. Hard, corrosion resistant layers of alloys rich in tungsten, cobalt, chromium or nickel can be sprayed onto surfaces, but a refinishing process is almost always necessary to restore the dimensional tolerances. Hard ceramic coatings such as AbO, Cr203, TiC, or TiN can be deposited by plasma methods and these not only give wear resistance but resistance to oxidation and... 

The first approach is based on introducing simple velocity or position rescaling into the standard Newtonian MD. The second approach has a dynamic origin and is based on a refonnulation of the Lagrangian equations of motion for the system (so-called extended Lagrangian formulation.) In this section, we discuss several of the most widely used constant-temperature or constant-pressure schemes. 

The second approach is to derive Lennard-Jones parameters for the quantum atoms that are specific to the problem in hand. This is a less common approach but has been shown to improve the quantitative accuracy of the QM-MM approach in specific cases [53,54]. The disadvantage of this approach, however, is that it is necessary to derive Lennard-Jones parameters for the quanmm region for every different study. Since the derivation of Lennard-Jones parameters is not a trivial exercise, this method of finding van der Walls parameters for the QM-MM interaction has not been widely used. 

Of these methods the first gives only marginal improvements whilst the second approach has far too severe an effect on the softening point to be of any commercial value. The use of fillers has been practised to some extent in the United States but is not of importance in Europe. Deliberate orientation is limited to filament and sheet. 

The second approach is typified by maleic anhydride. This material does not homopolymerise but will polymerise with styrene or styrene and acrylonitirle, in the latter case to give terpolymers with Tg above 122°C. 

The second approach to fracture is different in that it treats the material as a continuum rather than as an assembly of molecules. In this case it is recognised that failure initiates at microscopic defects and the strength predictions are then made on the basis of the stress system and the energy release processes around developing cracks. From the measured strength values it is possible to estimate the size of the inherent flaws which would have caused failure at this stress level. In some cases the flaw size prediction is unrealistically large but in many cases the predicted value agrees well with the size of the defects observed, or suspected to exist in the material. 

Blasius and coworkers have offered a somewhat different approach to systems of this general type. In the first of these, shown in Eq. (6.20), he utilizes a hydroxymethyl-substituted 15-crown-5 residue as the nucleophile. This essentially similar to the Mon-tanari method. The second approach is a variant also, but more different in the sense that covalent bond formation is effected by a Friedel-Crafts alkylation. In the reaction... 

In the second approach, the energy release is split by a predefined (mostly constant) factor between convection and radiation. The convective part is directly transferred as energy gain to the room air, while the radiative part is distributed to the surrounding walls by the area-weighted method or the view-factor method. 

For an existing process plant, the designer has the opportunity to take measurements of the fume or plume flow rates in the field. There are two basic approaches which can be adopted. For the first approach, the fume source can be totally enclosed, and a temporary duct and fan system installed to capture the contaminant. For this approach, standard techniques can be used to measure gas flow rates, gas compositions, gas temperatures, and fume loadings. From the collected fume samples, the physical and chemical characteristics can be established using standard techniques. For most applications, this approach is not practical and not very cost effec tive. For the second approach, one of three field measurement techniques, described next, can be used to evaluate plume flow rates and source heat fl uxes. 

In the second approach, a value for is not assumed but a relationship for dip/dT is determined from semi-empirical expressions for the amount of cooling air that is required in an (elementary) turbine blade row. One such relationship, derived in Ref. [5], gives... 

Disciplined methods are those proven methods that employ fundamental principles to reveal information. There are two different approaches to problem solving. The first is used when data is available, as is the case when dealing with nonconformities. The second approach is when not all the data needed is available. 

Computer simulations of bulk liquids are usually performed by employing periodic boundary conditions in all three directions of space, in order to eliminate artificial surface effects due to the small number of molecules. Most simulations of interfaces employ parallel planar interfaces. In such simulations, periodic boundary conditions in three dimensions can still be used. The two phases of interest occupy different parts of the simulation cell and two equivalent interfaces are formed. The simulation cell consists of an infinite stack of alternating phases. Care needs to be taken that the two phases are thick enough to allow the neglect of interaction between an interface and its images. An alternative is to use periodic boundary conditions in two dimensions only. The first approach allows the use of readily available programs for three-dimensional lattice sums if, for typical systems, the distance between equivalent interfaces is at least equal to three to five times the width of the cell parallel to the interfaces. The second approach prevents possible interactions between interfaces and their periodic images. 

The second approach, the multienergy method (Van den Berg 1985) reflects current consensus that turbulence is the major cause of explosive, blast-generating... 

The consequence of the second approach is that, if detonation of unconfined parts of a vapor cloud can be ruled out, the cloud s explosive potential is not primarily determined by the fuel-air mixture in itself, but instead by the nature of the fuel-release environment. The multienergy model is based on the concept that explosive combustion can develop only in an intensely turbulent mixture or in obstructed and/or partially confined areas of the cloud. Hence, a vapor cloud explosion is modeled as a number of subexplosions corresponding to the number of areas within the cloud which bum under intensely turbulent conditions. 

The second approach, developed by Woodward and co-workers and repeatedly applied by others, involves the condensation... 

The second approach is the synthesis of a suitable functionalized thiazitidine followed by constructing the quinoline ring. Thus, cyclization of 44 with a dihaloalkane gave 45 which upon cyclization afforded 26 and 27 (92JMC4727) (Scheme 8). 

Since the mid-1980s, FCC technology licensors and a number of oil companies have employed a number of RTD s to reduce non-selective post-riser cracking reactions. Two general approaches have been used to reduce post riser cracking. The most widely used approach is direct connection of the cyclones to the riser and on to the reactor vapor line. The second approach is quenching the reactor vapors downstream of the riser-cyclones (rough-cut cyclones). 

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