PAIRS program

Collective ownership—no programmer owns code, but a team will collaborate, possibly using pair programming, vetting each others work. 

Since its introduction to the scientific community in late 1980, PAIRS (Program for the Analysis of IR Spectra) has been used successfully by a large number of researchers. Recent improvements to PAIRS have made this package incorporate most of the aspects of expert systems. The improvement highlighted in this paper is the capability for scientists to inquire of the system why a particular interpretation result was achieved. This capability enhances the ability for scientists to learn from the knowledge base of interpretation rules present in PAIRS. It also simplifies the process by which the PAIRS knowledge base can be refined through incorporation of improved rules from expert spectroscopists. 

One of the weaknesses of the treatment of mini-crystal lattices with molecular mechanics is that these computations do not take into account electronic effects, and in the case of open-shell species such as triplets, electronic energy differences between reactants and intermediate and other transformation structures may be appreciable. Yet ab initio and even semi-empirical computations on the entirety of a mini-crystal lattice are formidable. Thus, an alternative was developed. This involved generation of a cavity shell composed of inert gas atoms. The Pairs program was used to identify atoms belonging to the neighboring molecules that were nearest to the reacting central molecule. The number of these nesu est atoms varied. Then, all but these nearest atoms were compu-... 

Tomellini, S. A., Hartwick, R. A., Woodruff, H. B. Automatic Tracing and Presentation of Interpretation Rules Used by PAIRS Program for the Analysis of IR Spectra. Appl. Spectrosc. 1985, 39, 331-333. 

Given the pair and surface potentials, the weights are then constructed by solving the convex bound constrained quadratic program... 

The connection table of the query object (similarity probe) is processed to obtain the set of atom pairs, and then the database file is scanned to evaluate the similarity between the query and each of the database structures. The maximum number of structures that the program will select is specified, as well as the minimum similarity score that a database compoimd must show to be selected. Within these limits, the program will select from the database the structures that are most similar (with the highest similarity value) to the query and will create an output file of compoimd numbers and similarity values, sorted by decreasing similarity, for the selected compounds. 

Woodruff and co-workers introduced the expert system PAIRS [67], a program that is able to analyze IR spectra in the same manner as a spectroscopist would. Chalmers and co-workers [68] used an approach for automated interpretation of Fourier Transform Raman spectra of complex polymers. Andreev and Argirov developed the expert system EXPIRS [69] for the interpretation of IR spectra. EXPIRS provides a hierarchical organization of the characteristic groups that are recognized by peak detection in discrete ames. Penchev et al. [70] recently introduced a computer system that performs searches in spectral libraries and systematic analysis of mixture spectra. It is able to classify IR spectra with the aid of linear discriminant analysis, artificial neural networks, and the method of fe-nearest neighbors. 

In some force fields the interaction sites are not all situated on the atomic nuclei. For example, in the MM2, MM3 and MM4 programs, the van der Waals centres of hydrogen atoms bonded to carbon are placed not at the nuclei but are approximately 10% along the bond towards the attached atom. The rationale for this is that the electron distribution about small atoms such as oxygen, fluorine and particularly hydrogen is distinctly non-spherical. The single electron from the hydrogen is involved in the bond to the adjacent atom and there are no other electrons that can contribute to the van der Waals interactions. Some force fields also require lone pairs to be defined on particular atoms these have their own van der Waals and electrostatic parameters. 

It is also possible to extend this concept to cover the presence of more than one distinct segm pair in a pair of sequences (for example, if there are three MSPs present with scores of 40, and 50 then one can calculate the probabOity of finding three pairs with at least a score of by chance). The ability of BLAST to provide a quantitative significance of any match fou is a particularly useful feature of the program, which, with its continuing development a availability, has made it the most widely used method for sequence database searching. 

The DIM statement in Program QENTROPY sets aside 100 memory locations for the experimental data points. It is necessary for any data set having more than 12 data pairs. What is the entropy of Pb at 100 and 200 K Make a rough sketch of the curve of C, vs. T for lead. Sketch the curve of Cp/T vs. T for lead. 

The first line in File 9-1 is the route section calling for a PM.3 optimization. The next three lines are a blank line, a program label (human input not read by the system), and a blank line. The input (J I indicates that the charge on the molecule is 0 and the spin multiplicity is I (paired electrons). The starting geometry is given in... 

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