Computer historical view

Abstract A historical view demystifies the subject. The focus is strongly on chemistry. The application of quantum mechanics (QM) to computational chemistry is shown by explaining the Schrodinger equation and showing how this equation led to the simple Hiickel method, from which the extended Hiickel method followed. This sets the stage well for ab initio theory, in Chapter 5. 

The only heteroatom which we consider is H (via adsorption of H2O). As our subject is periodic calculations, amorphous films are outside the scope of this review. The large body of work on adsorption onto titanium oxide of organic molecules or metal nanoparticles is reviewed in Ref [1]. Metals on oxide supports are covered in the chapter by N. Roesch (in this volume). Two related reviews consider the computation of thin films [2] and polar surfaces, especially their reconstruction [3]. Useful overviews of surface science techniques and terminology, as well as historical views of work on metal surfaces, are given in Refs. [4,5]. 

John R, Coupland S (2007) Type-2 fuzzy logic a historical view. Comput Intel Mag IEEE... 

Many attempts have been undertaken to rewrite the one-electron Dirac equation — of hydrogen-like atoms and also the mean-field SCF type derived in chapter 8 and in matrix form in chapter 10 — to obtain a form that is most suitable for numerical computations. Historically, the transformation and elimination techniques first emerged from such endeavors and were only later studied from a formal point of view as an essential part of the complete picture of relativistic many-electron theory. For instance, the DKH theory was first developed as an efficient low-order approximation to the Dirac equa-... 

To many, mass spectrometry is synonymous with El mass spectrometry. This view is understandable for two reasons. First, historically, El was universally available before other ionization methods were developed. Much of the early work was El mass spectrometry. Second, the major libraries and databases of mass spectral data, which are relied upon so heavily and cited so often, are of El mass spectra. Some of the readily accesible databases contain El mass spectra of over 390,000 compounds and they are easily searched by efficient computer algorithms. The uniqueness of the El mass spectrum for a given organic compound, even for stereoisomers, is an almost certainty. This uniqueness, coupled with the great sensitivity of the method, is... 

Many literature sources document closed-form algebraic expressions for view factors. Particularly comprehensive references include the compendia by Modest (op. cit., App. D) and Siegel and Howell (op. cit., App. C). The appendices for both of these textbooks also provide a wealth of resource information for radiative transfer. Appendix F of Modest, e.g., references an extensive listing of Fortan computer codes for a variety of radiation calculations which include view factors. These codes are archived in the dedicated Internet web site maintained by the ublisher. The textbook by Siegel and Howell also includes an extensive atabase of view factors archived on a CD-ROM and includes a reference to an author-maintained Internet web site. Other historical sources for view factors include Hottel and Sarofim (op. cit., Chap. 2) and Hamilton and Morgan (NACA-TN 2836, December 1952). 

Fig. 3. Perspective drawing of the main-chain conformation of domestic hen egg-white lysozyme. The view is an elevation from the active-site side of the molecule (Imoto et al., 1972). Only the positions of the a-carbon atoms are shown. An instructive colored painting by I. Geis of the original three-dimensional model of lysozyme is reproduced in the early review by Phillips (1966). Of historic interest is the drawing of the model by the late Sir Lawrence Bragg (reproduced by Blake et al., 1965, and Phillips et al., 1987). It is to be noted that Bragg s diagram is a free-hand drawing and not an accurate computer-generated representation of the molecule. (Reproduced with permission from Imoto et al., 1972.)...

Einally, we draw attention to several review articles in this area. In 1986 Lowdin 23 considered various aspects of the historical development of computational QC in view of the development of both conventional supercomputers and large-scale parallel computers. More recently, Weineri24 presented a discussion on the programming of parallel computers and their use in molecular dynamics simulations, free energy perturbation, and large scale ab initio calculations, as well as the use of very elaborate graphical display programs in chemistry research. We also note a review on the use of parallel processors in... 

Although the riskiness of a company depends on how investors view its future performance, company betas are estimated from the historic relationship of the company s stock to the overall stock market. The assumption is that the systematic riskiness of a company today is probably similar to its riskiness in the recent past. Betas for individual firms and for industries are computed, from stock market price and returns data available in several databases for publicly traded firms. 

The BE methods are widely used in quantum chemical calculations of solvent effects [2,3,5] with very good results. For historical reasons, the use of BE methods in molecular mechanics calculations is limited. Several versions of the BE method that differ in the cavity surface formation algorithms, evaluation of the Ese contribution, Eq. (16), and methods of solving the system of linear equations, Eq. (12), have been reported [18 22]. From a computational point of view, the BE methods are invariant to molecular rotations because the molecular surface is invariant to the rotation. The results will depend upon the method chosen for the formation and tessellation of the molecular surface. The time limiting step in BE methods is the solution of the system of linear equations (Eq. (12)). Even for relatively small proteins, the size of matrix A... 

The third major review dealing with methylene was Schaefer s 1986 Science article titled Methylene A Paradigm for Computational Quantum Chemistry in which he says The year 1970 has been suggested as a starting date for the third age of quantum chemistry, in which theory takes on not only qualitative but also quantitative value. In fact, each of the years 1960, 1970, 1972, and 1977 is of historical value in unraveling the structure and energetics of the CH2 molecule, methylene. I certainly agree especially in view of the number of submissions in 1970 related to CH2. 

Being the first paper of the annual report to be devoted to the computer processing of NMR spectra, this review attempts to cover this field from the beginning. In view of the selected historical approach, and given the wealth of literature devoted to the question, this paper will mainly focus on directing the reader towards other literature sources as there is very little scope for further details. 

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