Experimental Validity

Experimental validity means that the conclusions drawn on inference are true, relative to the perspective of the research design. There are several threats to inference conclusions drawn from experimentation, and they include (1) internal validity, (2) external validity, (3) statistical conclusion validity, and (4) construct validity. 

Internal validity is the validity of a particular study and its claims. It is a cause-effect phenomenon. To assure internal validity, researchers are strongly advised to include a reference or control arm when evaluating a test condition. A reference arm is a treatment or condition in which the researcher has a priori knowledge of the outcome. For example, if a bacterial strain of Staphylococcus aureus, when exposed to a 4% chlorhexidine gluconate (CHG) product, is generally observed to xmdergo a 2 logio reduction in population after 30 sec 

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The SPATE technique is often used to perfonn an experimental validation of the physical behaviour of stressed structures or components. This is the reason why the design activity is usually combined with the SPATE technique used on prototypes in order to provide a good set up of mechanically stressed elements. 

Figure 3-12 is a schematic of a deflagration suppressant system for process equipment. Each application requires experimental validation of the suppression system design. 

Some workers have correlated experimental data in terms of k at the arithmetic mean temperature, and some at the temperature of the bulk plasma. Experimental validation of the true effective thermal conductivity is difficult because of the high temperatures, small particle sizes and variations in velocity and temperature in plasma jets. 

This nucleation potential will approach its maximum value asymptotically as the potential of prepolarization is shifted to more cathodic values. In order to check the experimental validity of this prediction, this equation can be rearranged ... 

Celata GP, Moiini GL, Marconi V, McPhail SS, Zummo G (2005) Using viscous heating to determine the friction factor in micro-channels an experimental validation, in Proceedings of ECI international Conference on Heat Transfer and Fluid Flow in MicroChannel, Caste/Vecchio Pascoli, Italy, 25-30 September 2005... 

EXPERIMENTAL VALIDATION OF CONCEPTS 13.4.1 Cross-Linking of Maleated Polybutadiene... 

F. Dinkelacker 2003, Experimental validation of flame regimes for highly turbulent premixed flames. Proceedings of the First European Combustion Meeting ECM2003. See also the 27th Symp.(Int.) on Combustion, pp. 857-865, 1998. 

Bier, M Mosher, RA Palusinski, OA, Computer Simulation and Experimental Validation of Isoelectric Focusing in Ampholine-Free Systems, Journal of Chromatography 211, 313, 1981. Bier, M Palusinski, OA Mosher, RA Saville, DA, Electrophoresis Mathematical Modeling and Computer Simulation, Science 219, 1281, 1983. 

Shen M, Beguin C, Golbraikh A, Stables JP, Kohn H, Tropsha A. Application of predictive QSAR models to database mining identification and experimental validation of novel anticonvulsant compounds. J Med Chem 2004 47(9) 2356-64. 

So much for the advantages. Virtual organs clearly have one major drawback they are models only. While this very nature of in silico technology is the core foundation for the benefits listed above, it also calls for a word of caution. It is imperative for in silico tools to be seen in the context of a whole range of scientific and research tools, and to never neglect that theoretical considerations will continue to need experimental validation. 

Fig. 8.12 Experimental validation of the predicted conformation and the actual binding mode of compound 43. The X-ray structure is overlaid with its calculated counterpart (colored in orange).

A theoretical approach has also been taken to predicting the droplet formation from a pMDI, and this was followed by experimental validation studies [31,32],... 

The first pesticide exposure study was reported by Griffiths et al. (1951). Parathion was trapped on respirator filter discs during application to citrus trees. Batchelor and Walker (1954) expanded exposure monitoring to include the estimation of potential dermal exposure using pads attached to workers clothing. Durham and Wolfe (1962), in their classic review of worker exposure methodologies, also provided some experimental validation for the best available methods. 

Gogate PR, Mujumdar S, Pandit AB (2003) Large scale sonochemical reactors for process intensification Design and experimental validation. J Chem Tech Biotech 78 685-693... 

Bogen S, Vani K, McGraw B, et al. Experimental validation of peptide immunohistochemistry controls. Appl. Immunohistochem. Mol. Morphol. 2009 17 239-246. 

Equations of state relate the phase properties to one another and are an essential part of the full, quantitative description of phase transition phenomena. They are expressions that find their ultimate justification in experimental validation rather than in mathematical rigor. Multiparameter equations of state continue to be developed with parameters tuned for particular applications. This type of applied research has been essential to effective design of many reaction and separation processes. 

Fig. 6. Examples of types of meshes developed to resolve laminar flow around particles (a) Chimera grid. Reprinted, with permission, from the Annual Review of Fluid Mechanics, Volume 31 1999 by Annual Reviews www.annualreviews.org (b) Unstructured grid with layers of prismatic cells on particle surfaces. Reprinted from Chemical Engineering Science, Vol. 56, Calis et al., CFD Modeling and Experimental Validation of Pressure Drop and Flow Profile in a Novel Structured Catalytic Reactor Packing, pp. 1713-1720, Copyright (2001), with permission from Elsevier.

Yet Crowley went significantly beyond the claim to scientific validity made by his immediate predecessors in the Golden Dawn and positioned the A.A. as a kind of official sanctioning body for experimental validity and for scientific training. Crowley laid down a set of numbered rules governing experiments, proclaiming, for example ... 

Yanniotis, S. and P. A. Pilavachi. Mathematical Modeling and Experimental Validation of an Absorber-Driven Multiple Effect Evaporator. Chem Eng Technol 19 448-455 (1996). 

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