Empirical Research

As already suggested, quantification in electron spectroscopy has been the active research area of a number of the best practitioners in the field. Efforts in ESCA were originally championed by Wagner [46,47], who has researched empirically derived, atomic, sensitivity factor scales [47]. Further development has been provided by Wagner et al. [48], Nefedov et al. [49], Seah (primarily for Auger spectroscopy) [50] and Powell [51] (primarily for ESCA). 

Main objectives of stage 2 research Empirical understanding of the theme (practical) Definition of methodology steps Definition of the main problem, propositions, research questions and variables... 

Vafidis, D. 2002. Methodological Tendencies in Logistics Research Empirical Evidence from 25 Finnish and Swedish Doctoral Dissertations 1994-1998, Turku School of Economics and Business Administration Finland. 

Unfortunately, despite much research into the fundamentals of catalysis, the choice of catalyst is still largely empirical. The catalytic process can be homogeneous or heterogeneous. 

Presell is the basic theory of tjuaiiHim mechanics, particularly, semi-empirical molecular orbital theory. The authors detail and justify the approximations inherent in the semi-empirical Ham illoTi ian s. Includes useful discussion s of th e appiicaliori s of these methods to specific research problems. 

In chemistry, there was clearly a great need to move ahead and bridge the gap between the earlier, entirely empirical approach of teaching and research and that incorporating the new trends of chem-... 

Example Researchers have used MNDO and AMI semi-empirical methods to calculate possible reaction pathways for the interaction of glycine and cocaine. In choosing possible interaction sites,... 

The researchers established that the potential energy surface is dependent on the basis set (the description of individual atomic orbitals). Using an ab initio method (6-3IG ), they found eight Cg stationary points for the conformational potential energy surface, including four minima. They also found four minima of Cg symmetry. Both the AMI and PM3 semi-empirical methods found three minima. Only one of these minima corresponded to the 6-3IG conformational potential energy surface. 

HyperChem currently supports one first-principle method ab initio theory), one independent-electron method (extended Hiickel theory), and eight semi-empirical SCFmethods (CNDO, INDO, MINDO/3, MNDO, AMI, PM3, ZINDO/1, and ZINDO/S). This section gives sufficient details on each method to serve as an introduction to approximate molecular orbital calculations. For further details, the original papers on each method should be consulted, as well as other research literature. References appear in the following sections. 

ZINDO/S is an modified INDO method parameterized to reproduce UV visible spectroscopic transitions when used with the Cl singles methods. It was developed in the research group of Michael Zerner of the Quantum Theory Project at the University of Florida. As with the other semi-empirical methods, HyperChem s implementation of ZINDO/S is restricted to spin multiplicities of up to a quartet state. Higher spin systems may not be done using HyperChem. 

The viscosity of a polymer solution is one of its most distinctive properties. Only a minimum amount of research is needed to establish the fact that [77] increases with M for those polymers which interact with the solvent to form a random coil in solution. In the next section we shall consider the theoretical foundations for the molecular weight dependence of [77], but for now we approach this topic from a purely empirical point of view. 

Rate of Mass Transfer in Bubble Plates. The Murphree vapor efficiency, much like the height of a transfer unit in packed absorbers, characterizes the rate of mass transfer in the equipment. The value of the efficiency depends on a large number of parameters not normally known, and its prediction is therefore difficult and involved. Correlations have led to widely used empirical relationships, which can be used for rough estimates (109,110). The most fundamental approach for tray efficiency estimation, however, summarizing intensive research on this topic, may be found in reference 111. 

Empire State Electric Energy Research Corporation... 

Asbestos Control and Replacements Guidelines for Electric Utilities, Electric Power Research Institute, Palo Alto, Calif., and Empire State Electric Energy Research Corp., N.Y., Aug. 1994. 

Information for this article came from numerous sources, including F. E. Porretto, D. M. DiMeo, and S. Collins (Empire State Electric Energy Research Corp.), E. A. DeMeo and E. E. Hughes (Electric Power Research Institute) J. M. Cohen and D. Entingh (Princeton Economic Research, Inc.) and G. Sommers and J. Renner (Idaho National Engineering Laboratory). 

Many sophisticated models and correlations have been developed for consequence analysis. Millions of dollars have been spent researching the effects of exposure to toxic materials on the health of animals the effects are extrapolated to predict effects on human health. A considerable empirical database exists on the effects of fires and explosions on structures and equipment. And large, sophisticated experiments are sometimes performed to validate computer algorithms for predicting the atmospheric dispersion of toxic materials. All of these resources can be used to help predict the consequences of accidents. But, you should only perform those consequence analysis steps needed to provide the information required for decision making. 

The molecular and liquid properties of water have been subjects of intensive research in the field of molecular science. Most theoretical approaches, including molecular simulation and integral equation methods, have relied on the effective potential, which was determined empirically or semiempirically with the aid of ab initio MO calculations for isolated molecules. The potential parameters so determined from the ab initio MO in vacuum should have been readjusted so as to reproduce experimental observables in solutions. An obvious problem in such a way of determining molecular parameters is that it requires the reevaluation of the parameters whenever the thermodynamic conditions such as temperature and pressure are changed, because the effective potentials are state properties. 

Research looking into tolerance allocation in assembly stacks is by no means new. A current theme is towards an optimization approach using complex routines and/ or cost models (Lin et al., 1997 Jeang, 1995). Advanced methods are also available, such as Monte Carlo Simulation and Method of Moment. ) (Chase and Parkinson, 1991 Wu et al., 1988). The approach presented here is based on empirical process capability measures using simple tolerance models, cost analogies and optimization... 

To date, there has been relatively little work reported on the mesophase pitch rheology which takes into account its liquid crystalline nature. However, several researchers have performed classical viscometric studies on pitch samples during and after their transformation to mesophase. While these results provide no information pertaining to the development of texture in mesophase pitch-based carbon fibers, this information is of empirical value in comparing pitches and predicting their spinnability, as well as predicting the approximate temperature at which an untested pitch may be melt-spun. 

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