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Flexible reference

Flexible refers to a process which remains feasible for every value of the uncertain variables in the uncertainty range despite desired changes to the process (e.g., supply temperature and flow rate variations due to feedstock changes). [Pg.9]

The considerations discussed above clearly show that multireference Cl approaches to the study of excited states require great care and are not well suited to black-box applications. Ideally, one would like a method that retains the conceptual simplicity of the ACI approach while providing a better description of excited states. Since the problems associated with the ACI method are due to the use of a single determinant reference state for all electronic states, one might naturally wonder whether a better (more flexible) reference state can be used. In other words, we assume the same form of the excited state wavefunction... [Pg.143]

Flexibility refers to the tactical ability of an entire production and logistics area to switch within reasonably little time and effort to new, albeit similar, families of components by changing manufacturing processes, material flows, and logistical functions. [Pg.159]

Suhai computed the first derivative of the energy with respect to the elongation (the force acting due to deformation on the polymer) and observed a nearly linear increase until e 0.05, but then a clear deviation from Hooke s law is evident. This deviation is about 15% at 0.1, but increases very sharply for larger values of e. Since correlation fundamentally influences this deviation, one has to investigate this region more carefully, using better basis sets and a more flexible reference state for the perturbation theory or for other methods to account for the correlation. [Pg.378]

Volume flexibility refers to a firm s ability to operate profitably at different levels of output. Volume flexibility is critical in cychcal industries. Firms in the automotive industry that lacked volume flexibihty were badly hurt in 2008 when demand for automobiles in the United States shrank significantly. The steel industry is an example in which some volume flexibility and consolidation have helped performance. Prior to 2000, firms had limited volume flexibility and did not adjust production volumes when demand started to fall. The result was a buildup of inventories and a significant drop in the price of steel. In the early 2000s, a few large firms consolidated and developed some volume flexibility. As a result, they were able to cut production as demand fell. The result has been less buildup of inventory and smaller drops in price during downturns, followed by a quicker recovery for the steel industry. [Pg.150]

IT infrastructure flexibility refers to the extent to which systems (i.e. hardware, software, communication technologies, and database) are easily reconfigurable to support different business applications and services. IT infrastructure comprises information and communication technologies as well as shared technical platforms and databases (Ross et al. 1996 Weill et al. 1996 Bharadwaj 2000). The primary constituents of IT infrastructure are computing platform (hardware and operating systems), communications network, critical shared database, and core applications (Byrd and Turner 2000). IT infrastructure is the foundation of IT assets (i.e., technical and human assets) and services shared across a firm (Piccoli and Ives 2005). As a result, IT infrastructure provides shared foundation for the delivery of business applications and services (Broadbent and Weill 1997). [Pg.33]

We are confident that any user of this combined evaluation technique, as well as the development of future test standards for manual ultrasonic testing will benefit from this result, because it allows a greater flexibility in the applicable method without loosing reliability. Often an expensive production of a reference block can be avoided and therefore testing costs are reduced. Since all calculations are performed by a PC, the operator can fully concentrate on his most important duty scanning the workpiece and observing the A-scan. Additional time will be saved for the test documentation, since all testing results are stored in the instrument s memory (the PC s hard drive) with full link to the Software World (Microsoft Word, Excel, etc.). [Pg.818]

In addition these directives had to be decided unanimously by the European Council which made their adoption cumbersome and slow. These directives are now referred to as old approach directives. A radical change was needed so that the Community legislation could respond to the needs of both, the completion of the internal market for the products concerned, and the need to offer to industry a flexible legislative environment which would encourage technical progress. [Pg.937]

In practice, each CSF is a Slater determinant of molecular orbitals, which are divided into three types inactive (doubly occupied), virtual (unoccupied), and active (variable occupancy). The active orbitals are used to build up the various CSFs, and so introduce flexibility into the wave function by including configurations that can describe different situations. Approximate electronic-state wave functions are then provided by the eigenfunctions of the electronic Flamiltonian in the CSF basis. This contrasts to standard FIF theory in which only a single determinant is used, without active orbitals. The use of CSFs, gives the MCSCF wave function a structure that can be interpreted using chemical pictures of electronic configurations [229]. An interpretation in terms of valence bond sti uctures has also been developed, which is very useful for description of a chemical process (see the appendix in [230] and references cited therein). [Pg.300]

Finally, from the dynamics simulations it was found that the Cp rings are very flexible, and during the simulation they are not very closely attached to the metal centre as often anticipated. For further details regarding the metallocene and mono-cyclopentadienyl based olefin polymerisation studied by quantum molecular dynamics simulation we refer to [2] and [8-10]. [Pg.437]

Commonly used isocyanates are toluene dhsocyanate, methylene diphenyl isocyanate, and polymeric isocyanates. Polyols used are macroglycols based on either polyester or polyether. The former [poly(ethylene phthalate) or poly(ethylene 1,6-hexanedioate)] have hydroxyl groups that are free to react with the isocyanate. Most flexible foam is made from 80/20 toluene dhsocyanate (which refers to the ratio of 2,4-toluene dhsocyanate to 2,6-toluene dhsocyanate). High-resilience foam contains about 80% 80/20 toluene dhsocyanate and 20% poly(methylene diphenyl isocyanate), while semi-flexible foam is almost always 100% poly(methylene diphenyl isocyanate). Much of the latter reacts by trimerization to form isocyanurate rings. [Pg.1022]

Mech nic lProperties. Extensive Hsts of the physical properties of FEP copolymers are given in References 58—63. Mechanical properties are shown in Table 3. Most of the important properties of FEP are similar to those of PTFE the main difference is the lower continuous service temperature of 204°C of FEP compared to that of 260°C of PTFE. The flexibiUty at low temperatures and the low coefficients of friction and stabiUty at high temperatures are relatively independent of fabrication conditions. Unlike PTFE, FEP resins do not exhibit a marked change in volume at room temperature, because they do not have a first-order transition at 19°C. They ate usehil above —267°C and are highly flexible above —79°C (64). [Pg.360]

Various geometric coring patterns ki polyurethanes (171,175) and ki latex foam mbber (176) exert significant influences on thek compressive behavior. A good discussion of the effect of cell size and shape on the properties of flexible foams is contained ki References 60 and 156. The effect of open-ceU content is demonstrated ki polyethylene foam (173). [Pg.413]

With its flexible and logical search language, REACCS can retrieve molecular stmctures, the atoms and bonds that are transformed ia a reaction, relative and absolute stereochemistry, the role (reactant, product, solvent, or catalyst) of a molecule ia a reaction, reaction data (eg, temperature and yield), hterature references, and keyword descriptions of reaction types. [Pg.125]

Some drawbacks to the weigh belt are that it is a zero-reference device and thus needs frequent caHbration (re-zeroing). Buildup on the belt and roUers affects accuracy and operation, as does belt tension and dusty or floodable materials. Flexible connections are required to isolate the feeder from upstream and downstream equipment, unless the belt feeder/weigh idler concept is used. [Pg.559]

PID controller is a flexible, effective, and rehable controller for the process industries. A considerable range of controller actions is possible by selecting tuning parameters to provide different weights to the present (proportional), the past (integral), and the projected future (derivative). References related to the tuning of PID controllers are available (20—24). [Pg.69]

Styrene—butadiene—styrene modified bitumen is an elastomeric material mixed into an asphalt between 10 and 15%. By using high energy mixing, the SBS is uniformly dispersed throughout the asphalt to form a network, referred to as phase reversal because the minor component s (SBS) physical properties are displayed by the final mixture. A properly formulated SBS asphalt blend has an elongation of 100% or greater and is flexible down to temperatures below —6°C. [Pg.321]


See other pages where Flexible reference is mentioned: [Pg.197]    [Pg.171]    [Pg.18]    [Pg.49]    [Pg.256]    [Pg.114]    [Pg.209]    [Pg.503]    [Pg.94]    [Pg.383]    [Pg.2]    [Pg.499]    [Pg.109]    [Pg.149]    [Pg.150]    [Pg.79]    [Pg.197]    [Pg.171]    [Pg.18]    [Pg.49]    [Pg.256]    [Pg.114]    [Pg.209]    [Pg.503]    [Pg.94]    [Pg.383]    [Pg.2]    [Pg.499]    [Pg.109]    [Pg.149]    [Pg.150]    [Pg.79]    [Pg.942]    [Pg.370]    [Pg.89]    [Pg.451]    [Pg.507]    [Pg.16]    [Pg.168]    [Pg.477]    [Pg.403]    [Pg.515]    [Pg.451]    [Pg.56]    [Pg.123]    [Pg.211]    [Pg.82]    [Pg.78]    [Pg.61]   
See also in sourсe #XX -- [ Pg.383 ]




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