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Handling criterion

We employ the general scheme presented above as a starting point in our discussion of various approaches for handling the R-T effect in triatomic molecules. We And it reasonable to classify these approaches into three categories according to the level of sophistication at which various aspects of the problem are handled. We call them (1) minimal models (2) pragmatic models (3) benchmark treatments. The criterions for such a classification are given in Table I. [Pg.489]

Implicit in cake filtration is the removal and handling of solids, since the cake is usually relatively dry and compacted. C es can be sticky and difficult to handle therefore, the ability of a filter to discharge the cake cleanly is an important equipment-selection criterion. [Pg.1708]

Reliable analytical methods are available for determination of many volatile nitrosamines at concentrations of 0.1 to 10 ppb in a variety of environmental and biological samples. Most methods employ distillation, extraction, an optional cleanup step, concentration, and final separation by gas chromatography (GC). Use of the highly specific Thermal Energy Analyzer (TEA) as a GC detector affords simplification of sample handling and cleanup without sacrifice of selectivity or sensitivity. Mass spectrometry (MS) is usually employed to confirm the identity of nitrosamines. Utilization of the mass spectrometer s capability to provide quantitative data affords additional confirmatory evidence and quantitative confirmation should be a required criterion of environmental sample analysis. Artifactual formation of nitrosamines continues to be a problem, especially at low levels (0.1 to 1 ppb), and precautions must be taken, such as addition of sulfamic acid or other nitrosation inhibitors. The efficacy of measures for prevention of artifactual nitrosamine formation should be evaluated in each type of sample examined. [Pg.331]

We use a method that implements the Unbiased Prediction Risk criterion [13] to provide a data-driven approach for the selection of the regularization parameter. The equality constraints are handled with LQ factorization [14] and an iterative method suggested by Villalobos and Wahba [15] is used to incorporate the inequality constraints [10]. The method is well suited for the relatively large-scale problem associated with analyzing each image voxel as no user intervention is required and all the voxels can be analyzed in parallel. [Pg.367]

When the vapour flows up the tube, which will be the usual arrangement for a reflux condenser, care must be taken to ensure that the tubes do not flood. Several correlations have been published for the prediction of flooding in vertical tubes, see Perry et al. (1997). One of the simplest to apply, which is suitable for use in the design of condensers handling low-viscosity condensates, is the criterion given by Hewitt and Hall-Taylor (1970) see also Butterworth (1977). Flooding should not occur if the following condition is satisfied ... [Pg.713]

For as instructive as root locus plots appear to be, this technique does have its limitations. The most important one is that it cannot handle dead time easily. When we have a system with dead time, we must make an approximation with the Pade formulas. This is the same limitation that applies to the Routh-Hurwitz criterion. [Pg.141]

Frequency response analysis allows us to derive a general relative stability criterion that can easily handle systems with time delay. This property is used in controller design. [Pg.142]

For a first order function with deadtime, the proportional gain, integral and derivative time constants of an ideal PID controller. Can handle dead-time easily and rigorously. The Nyquist criterion allows the use of open-loop functions in Nyquist or Bode plots to analyze the closed-loop problem. The stability criteria have no use for simple first and second order systems with no positive open-loop zeros. [Pg.258]

It should be clear that the procedure as just described cannot handle this program. For the inductive assertion pB attached to the critical point after each CALL F(x2,z) or F(u,z) will have as free variables only z and x2 or u, the actual parameters, but the output criterion B involves Xp and x2 and its value, depends on the relationship of Xp and x2 as well as the relationship between z and x2. We have so far provided no way to carry over a CALL assertions regarding variables not involved in the CALL. [Pg.287]

It is less clear how one should handle the requirement of unexpected and recurrent panic attacks. This is an inclusion criterion in form, while it is an exclusion criterion in function. This requirement can be operationalized either as a selection filter or as a component of the syndrome. We think it useful to break up unexpected and recurrent into two components and consider them separately. The unexpectedness of the panic attack is such a fundamental requirement in the DSM definition that it makes sense to operationalize it as a selection criterion. According to the DSM, individuals who have only experienced situationally bound panic attacks cannot have a panic disorder diagnosis, which can happen if this criterion is used as an indicator in CCK analyses. An individual can become a taxon member by being elevated on some, but not necessarily all, indicators. Moreover, unexpectedness of a panic attack cannot be easily coded as a continuous variable, which can present computational difficulties, especially for MAXCOV. [Pg.107]

The product type can be commodity or specialty. Commodity products are considered with a defined standard quality, where price is the key buying criterion. The product life cycle for chemical commodities can be relatively long meaning that the products are in the market partly for decades. Examples for short life cycle commodities on the other hand are semiconductors that are also mainly sold over price, but are shortly out-dated due to technology advances. The number of products is medium and does not reach the complexity of specialty product portfolios, where often more than 1,000 products need to be handled by a company. The product customization is standardized with some variants with respect to product properties but not related to a specific customer. Product perishability is... [Pg.98]

This sub-problem considers the mixture properties. Mixture properties can be categorized into two types. Properties such as selectivity, solvent power etc., are based on infinite dilution activity coefficients, which are independent of composition and hence only structural information is needed for their calculation. Properties such as complete or partial miscibility of solvent with another constituent is handled by discritizing the composition range from 0 to 1 into n divisions and verifying the miscibility criterion at those points. The difference between pure component property constraints and mixture property constraints is that the former are linear and the latter are non-linear. Those satisfying the mixture property constraints are further analyzed in sub-problem 4. [Pg.124]

The Routh stability criterion is quite useful, but it has definite limitations. It cannot handle systems with deadtime. It tells if the system is stable or unstable but it gives no information about how stable or unstable the system is. That is, if the test tells us that the system is stable, we do not know how close to instability it is. Another limitation of the Routh method is the need to express the character istic equation explicitly as a polynomial in s. This can become complex in high-order systems. [Pg.348]

The adaptations introduced in the fast exchange algorithm to optimize the UCC criterion allow selection from databases of hundreds of thousands of compounds. Currently, the implementation is limited to tens of continuous descriptors, though discrete descriptors like fragment counts could be handled in principle. Further work is also needed for even larger databases with hundreds of descriptors. [Pg.306]

Structural analysis of the solid rocket case-grain system using experimentally determined propellant response properties may permit a complete description of the combined stresses and resultant deformations, but a statement expressing the ability of the propellant to withstand these stresses is also required. Such a statement, which relates the physical state at which failure occurs to some material parameters, is called a failure criterion. The criterion for failure permits a prediction of safety margins expected under motor operation and handling and defines the loading regimes where abnormal operations will occur with intolerable frequency. [Pg.227]


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See also in sourсe #XX -- [ Pg.599 ]




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