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Establishing Benchmarking Comparisons

It is important to remember that performance is NOT an absolute measurement in and of itself. Rather it is a subjective evaluation based on a series of comparisons to an established benchmark. Benchmarks are an important tool, and not just in business analysis. Benchmarks help establish a set of expectations, a threshold for what is—and what is not—an acceptable performance level. [Pg.146]

As we stated earlier, one cannot directly measure good feel. While there may be physical properties one can measure (such as surface roughness, or density, or thermal conductivity), these properties will not be the only variables affecting the overall feel. In much the same way that performance is a subjective evaluation based on a comparison to an established benchmark, feel is also a subjective evaluation based on comparison. [Pg.265]

The latter authors used anode and cathode symmetrical cells in EIS analysis in order to simplify the complication that often arises from asymmetrical half-cells so that the contributions from anode/ electrolyte and cathode/electrolyte interfaces could be isolated, and consequently, the temperature-dependences of these components could be established. This is an extension of their earlier work, in which the overall impedances of full lithium ion cells were studied and Ret was identified as the controlling factor. As Figure 68 shows, for each of the two interfaces, Ra dominates the overall impedance in the symmetrical cells as in a full lithium ion cell, indicating that, even at room temperature, the electrodic reaction kinetics at both the cathode and anode surfaces dictate the overall lithium ion chemistry. At lower temperature, this determining role of Ra becomes more pronounced, as Figure 69c shows, in which relative resistance , defined as the ratio of a certain resistance at a specific temperature to that at 20 °C, is used to compare the temperature-dependences of bulk resistance (i b), surface layer resistance Rsi), and i ct- For the convenience of comparison, the temperature-dependence of the ion conductivity measured for the bulk electrolyte is also included in Figure 69 as a benchmark. Apparently, both and Rsi vary with temperature at a similar pace to what ion conductivity adopts, as expected, but a significant deviation was observed in the temperature dependence of R below —10 °C. Thus, one... [Pg.157]

If comparison with experiment is not appropriate, what should be used for reference values Clearly, the desirable thing would be to eliminate as many sources of error as possible. For instance, if we wish to establish the reliability of an SCF treatment in a given one-particle basis, we could use numerical Hartree-Fock results for diatomic molecules (that is, essentially complete basis results) as benchmarks. Any difference between the finite basis and numerical results would presumably be due to inadequacies in the former, as otherwise the same approximations are made in both treatments. It is crucial to understand that this approach gives much more informa-... [Pg.345]

A fundamental concept essential to the currently defined approaches for determining GMO safety is that of substantial equivalence (SE). Used as the basis for establishing a comparative benchmark, SE depends on two key concepts. Eirst, existing traditional foods are assumed to be safe as evidenced by their longterm use. Second, the response to traditional foods can be used as a basis for comparison to transgenically modified foods which are often derived from traditional foods. [Pg.1247]

As a compound proceeds into first-in-human clinical trials, the assay method reaches an apex in terms of performance. These methods require maximal sensitivity to be able to support dose escalation studies. The selectivity of the method is well established versus matrix components, concomitant medications, and metabolites. The assay is revalidated in the human matrices (plasma, serum, and urine) and will again meet well-established guidelines for inter- and intraday precision and accuracy. If significant changes are made to the method, a comparison of methods study will be conducted to understand the relative accuracy of the methods. After this benchmark, assay requirements, especially limit of quantitation, are usually less demanding and use of the assay becomes more routine, as it is applied again and again to additional clinical studies for pharmacokinetic support. [Pg.208]

When the governing model is given by the convection-diffusion equation (no electrical migration effects are considered), well-established numerical methods can be used directly in electrochemical cell design. When using commercial software, it should be remembered that the code has probably been benchmarked for applications different from those found in metallization, where spatial distributions of flux at high Schmidt numbers may be of more interest than the spatial average flux. Freitas has recently provided a comparison of several commercial CFD codes. Many of these codes are based on a finite-volume method (FVM) or a finite-element method. West jj yg discussed the application of... [Pg.359]

Since about 1980, considerable computational effort has been devoted to the determination of an accurate force field for benzene (146-157). Although detailed analyses of the experimental data go back 60 years (158), even the harmonic force field is not known to high accuracy from the experimental data. One reason for this situation is that benzene has five spectroscopically inactive vibrational modes and the number of independent quadratic force constants (34 for nonplanar benzene and 26 for the planar molecule) is too large to be determined by experimental information alone. Even establishing the harmonic frequencies has required considerable effort, because anharmonic corrections must be estimated for the measured fundamental frequencies. Recently, after years of detailed experimental and theoretical studies, Goodman and co-workers (149-152) have established a benchmark harmonic force field by combining all currently available IR, Raman, and one- and two-photon electronic excitation information from four isotopomers with theoretical calculations. This set of quadratic force constants and harmonic frequencies provides an important database for comparison with future theoretical studies. [Pg.104]

In recent years, higher orders of the DK transformation were formulated and explored in benchmark calculations on small molecules. Furthermore, it was shown that highly accurate transformed two-component Hamiltonians can be generated via the DK transformations of higher orders. These Hamiltonians converge quite well for the known elements of the periodic table limits of accuracy become noticeable only for elements with Z > 120. Higher orders of DK transformed Hamiltonians yield only small corrections for molecular observables thus, for most applications with normal demands of accuracy, DK2 is a reasonable, efficient, and well established choice. A valuable alternative is provided by the ZORA scheme, as comparison of available results shows. On the other hand, in the near future, accurate four-component approaches are expected to be essentially restricted to benchmark calculations due to their computational requirements. [Pg.711]

A third area that can become a problem for benchmarking is the availability of valid data from other organizations. In order to establish effective benchmarks, one must know the performance levels of other organizations. It may be difficult to obtain the necessary data from other companies, and if it is obtained, comparisons may be difficult due to differences in measurements used across industries. [Pg.103]

A third important component of the audit process is the performance indexing of the audit results. The task of performance indexing requires the results of the audit to be quantified in a manner that allows for comparisons against performance benchmarks. While the actual audits may identify the number of unsafe actions performed by personnel during an observation period, the raw numbers are really meaningless until they are placed in a context which is comparable to an established index. The performance indices established from an audit can include the percentages of unsafe acts performed, the frequencies of hazardous conditions identified, or the accident rates for a period of time to name a few. [Pg.109]

Benchmarks are established, behaviors are observed and quantified, comparisons are made to the benchmarks, and improvement activities are implemented. [Pg.120]

The series of dynamic centrifuge tests included an experiment (CT-A) intended to evaluate the fundamental behavior of the system through the analysis of a benchmark problem for further comparison with the subsequent tests. This test was also carried out to establish the influence of the bearing pressure induced by the shallow foundation on the liquefiable ground on the performance of the soil-structure system under seismic loading and to assess potential interaction effects between the structures placed in the same model. Figure 24.2 presents a scheme of the model... [Pg.427]

The choice of fundamental approximation, combined with the choice of parameter values, defines a particular SEMOT method, analogous to a force field in MM. Several established and novel SEMOT methods have been reviewed and compared elsewhere [54]. Among the three popular SEMOT methods mentioned earlier, MNDO/d is least widely available in commercial software packages. The other two methods, AMI and PM3, differ only in their parameterization. Since the PM3 method was parameterized more recently and more carefully, it is expected to be more reliable and will be the focus of discussion here. However, performance varies, so it should be compared with that of the experiment for related systems before putting faith in the predictions. Note that AMI and PM3 predictions are included in the Computational Chemistry Comparison and Benchmark Database (CCCBDB), which is a convenient, on-line resource for comparing theoretical predictions with experimental data [55]. [Pg.12]

MOFs by their nature are difficult to define and classify the link between MOFs and their impact on safety can be subtle and long-term data is hard to obtain because of the difficulty to establish appropriate taxonomies. The lack of an established set of MOFs and corresponding definitions hinders comparisons and benchmarking analyses across different studies. The reader can refer to (Mohaghegh et al. 2009), (Mohaghegh Mosleh, 2009) for a comprehensive discussion on the issue. [Pg.1075]


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Benchmarked

Establishing

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