Research Algorithm

The algorithm is the computer program that performs database research. There are several kinds of algorithms but they all utilize the same operational principle. To illustrate the operational principle of the algorithm of the signal treatment program that equips mass spectrometers, the VarianT algorithm is presented. The database contains 102,386 spectra. 

FIGURE 8.1 Reduction of electron ionization mass spectrum of a-pinene (a) to its 16 most abundant ions (b). 

Saturn Purity Search Results Hits Found 25 Pre-Search Hits Found 2517 Pre-Search Results Matches Count Total 

Saturn Purity Search Parameters Threshold 700 Target Ion Range 45-500 Library MW Range 0-500 Library Ion Rang 45-500 (Target Range) 

FIGURE 8.2 Results of pre-selection operated by the program on spectra reduced to 8 ions. 

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Slit-coil material optimization software is a technology that allows a company to address all of these conflicting objectives—low scrap, little overrun or overproduction, no restock, fewer setups, and quick calculation time. The optimization software, using specialized Operation Research algorithms, can mathematically consider every possible combination and permutation of slitting patterns on the available master coils. The fast processing time of today s PCs, combined with efficient programming techniques, allows the lowest overall cost solution to be calculated within a few minutes. 

The optimization software, using specialized Operations Research algorithms, considers all of the possible combinations of slitting patterns for producing... 

The optimization software, using specialized Operations Research algorithms, considers all of the possible master sizes between the minimum and maximum sizes specified. Efficient programming techniques, combined with the fast processing speed of today s PCs, allows the best master coil or master sheet sizes to be calculated within a few minutes. 

The Library Entry window at the bottom left of Figure 8.5 allows activation of the Local Normalization function. Note that this function is not present in aU research algorithms. If it is available, it can be used to perform the research giving preference to the heaviest ions, which are a priori the most characteristic of the target molecule. 

The eighth chapter deals with the use of databases in mass spectrometry. We compare the performances and limitations of laboratory-made and commercial mass spectra databases a database research algorithm is also described. The objective of this chapter is to encourage a critical approach to databases for a relevant and objective use. 

For the maximum use of advantages of a cone beam at collecting of data, it is necessary to study and develop effective algorithms of reconstmction for cone-beam projection data. The theory of reconstruction in cone beams is referred to as cone-beam tomography. It had developments in papers of many researchers. ... 

In recent decades, computer scientists have tried to provide computers with the ability to learn. This area of research was summarized under the umbrella term "machine learning . Today machine learning is defined as "the study of computer algorithms that improve automatically through experience [1]. 

Current research in LHASA is focused on developing new methods assisting users in choosing the most appropriate strategy for their target structures. Furthermore, the development of criteria for the evaluation of synthesis routes and/or algorithms for selecting optimal synthesis routes within the tree are discussed [34]. 

Advanced users can also benefit from reading this guide. Many people use a lim ited n n mber of algorith m s an d methods for chem -ical calculation s. This book compares of the differen t meth ods in IlyperChem and helps you determine the most appropriate method for your research problems. The book discusses strengths and weaknesses of the methods and algorithms. 

The calculation of reaction rates has not seen as the widespread use as the calculation of molecular geometries. In recent years, it has become possible to compute reaction rates with reasonable accuracy. However, these calculations require some expertise on the part of the researcher. This is partly because of the difficulty in obtaining transition structures and partly because reaction rate algorithms have not been integrated into major computational chemistry programs and thus become automated. 

Creating synthesis route prediction programs has been the work of a relatively small number of research groups in the world. There are nearly as many algorithms as there are researchers in the field. However, all these can be roughly classified into three categories. 

A second scheme uses a database of known chemical reactions. This more often results in synthesis routes that will work. However, this occurs at the expense of not being able to suggest any new chemistry. This method can also give many possible synthesis routes, not all of which will give acceptable yield or be easily carried out. The quality of results will depend on the database of known reactions and the means for determining which possible routes are best. These are often retro synthetic algorithms, which start with the desired product and let the researcher choose from a list of possible precursors. 

The first is a network that has minimum area but a maximum number of exchangers as proposed by the algorithmic—evolutionary approach (10). The algorithmic part of this method is the development of a minimum area network. The evolutionary part employs a set of rules to modify systematically the initial network. The three rules presented ate heuristic in nature and seek to combine exchangers and stream spHts to reduce network cost. The problem of reducing stream spHts appears difficult to researchers. 

Data Analysis. The computerization of spectrometers and the concomitant digitization of spectra have caused an explosive increase in the use of advanced spectmm analysis techniques. Data analysis in infrared spectrometry is a very active research area and software producers are constantly releasing more sophisticated algorithms. Each instmment maker has adopted an independent format for spectmm files, which has created difficulties in transferring data. The Joint Committee on Atomic and Molecular Physical Data has developed a universal format for infrared spectmm files called JCAMP-DX (52). Most instmment makers incorporate in thek software a routine for translating thek spectmm files to JCAMP-DX format. 

The overall objective of research under way as of ca 1997 is to develop a system of sale by description for fine and medium wools whereby the buyer is presented only with measured data on the principal characteristics of the raw wool, as well as an assessment of the less important characteristics by an independent skilled appraiser (8). A scheme for assessing the risk of the presence of colored fiber content in greasy wool has been proposed which depends on production parameters and on the age and sex of the sheep (5). Instmmentation and computer algorithms for the measurement of style and handle... 

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. 

Petersen, W. B., and Rumsey, E. D., "User s Guide for PAL 2.0—A Gaussian Plume Algorithm for Point, Area, and Line Sources," EPA/600/8-87/009. U.S. Environmental Protection Agency, Research Triangle Park, NC, 1987 (NTIS Accession No. PB87-168 787). 

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