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Discriminant combined

Combined Distance Discriminant Combining the information available in scores and residuals usually improves the diagnosis accuracy [206]. Comparing the combined information to the confidence limits of each fault model, X is most likely to be from the fault model i with minimum... [Pg.183]

Commercial preamplifier-discriminator combinations come in both fixed threshold and variable threshold versions the former is normally optimized by the manufacturer. In practice, a discriminator threshold level of 2-20 mV offers optimal performance at a lower threshold the electronics would become susceptible to electric-noise interference, and higher thresholds would require higher gain to be achieved by the detector itself and by the preamplifier stage. [Pg.214]

Percus J K, Percus O E and Perelson A S 1993 Predicting the size of the T-cell receptor and antibody combining region from consideration of efficient self-nonself discrimination Proc. Natl Acad. Sci. USA 90 1691-5... [Pg.2850]

Discriminant emalysis is a supervised learning technique which uses classified dependent data. Here, the dependent data (y values) are not on a continuous scale but are divided into distinct classes. There are often just two classes (e.g. active/inactive soluble/not soluble yes/no), but more than two is also possible (e.g. high/medium/low 1/2/3/4). The simplest situation involves two variables and two classes, and the aim is to find a straight line that best separates the data into its classes (Figure 12.37). With more than two variables, the line becomes a hyperplane in the multidimensional variable space. Discriminant analysis is characterised by a discriminant function, which in the particular case of hnear discriminant analysis (the most popular variant) is written as a linear combination of the independent variables ... [Pg.719]

The combined inductive and field effects of these poles do not produce strong discrimination between the m- and /i-positions in nitration m p for. NMe3+, and smaller for the protonated poles). This situation is in marked contrast to that produced by, say, the nitro group ( 9.1.3), and suggests that the —M effect is more discriminating between m- and -positions than is the — I effect. [Pg.169]

Eig. 2. Thermography combined with precise spectral discrimination provides for spatial spectroscopy for remote spectral sensing as well as "spot sensing"... [Pg.292]

The success of quinine inspired the search for other antimalarials. The greatest impetus for the development of synthetic dmgs came this century when the two World Wars intermpted the supply of cinchona bark to the combatants. A stmcturally related 4-quinolinemethanol is mefloquine (65, Lariam [51773-92-3]) which now serves as an effective alternative agent for chloroquine-resistant P. falciparum. This is a potent substance that requires less than one-tenth the dose of quinine to effect cures. There are some untoward side effects associated with this dmg such as gastrointestinal upset and dizziness, but they tend to be transient. Mefloquine is not recommended for use by those using beta-blockers, those whose job requires fine coordination and spatial discrimination, or those with a history of epilepsy or psychiatric disorders. A combination of mefloquine with Fansidar (a mixture of pyrimethamine and sulfadoxine) is known as Fansimef but its use is not recommended. Resistance to mefloquine has been reported even though the compound has not been in wide use. [Pg.273]

In recent years, enantioselective variants of the above transannular C-H insertions have been extensively stiidied. The enantiodetermining step involves discrimination between the enantiotopic protons of a meso-epoxide by a homochiral base, typically an organolithium in combination with a chiral diamine ligand, to generate a chiral nonracemic lithiated epoxide (e.g., 26 Scheme 5.8). Hodgson... [Pg.148]

Pain is a combination of sensory (discriminative) and affective (emotional) components. The sensoiy component of pain is defined as nociception. [Pg.928]

Often a phosphorus-containing surfactant provides the combination of desired characteristics, e.g., wettability, detergency, and anticorrosiveness. Thus classification by discriminate application is difficult. The following structure only serves the purpose of a better survey. The limits between specific sections are hazy, and as a result the mentioned surfactants encompass more than one characteristic. [Pg.598]

Solberg and co-workers have applied discriminate analysis of clinical laboratory tests combined with careful clinical and anatomic diagnoses of liver disease in order to determine which combinations of the many dozen liver diagnostic tests available are the bes t ( ). These authors found that the measurement of GPT, GMT, GOT, ALP and ceruloplasmin were the most useful enzymatic tests, when combined with other non-enzymatic tests such as the measurement of bilirubin, cholesterol, hepatitis-B associated Australian antigen, etc. Another group of highly useful enzymes, not discussed in this review, are those clotting factors and the enzyme cholinesterase which are synthesized by the liver cells. [Pg.208]

Diagnosis of liver diseases by laboratory results and discriminant analysis. Identification of best combinations of laboratory tests. Scand. J. Clin. Lab. Invest. [Pg.222]

Linear, polynomial, or statistical discriminant functions (Fukunaga, 1990 Kramer, 1991 MacGregor et al., 1991), or adaptive connectionist networks (Rumelhart et al, 1986 Funahashi, 1989 Vaidyanathan and Venkatasub-ramanian, 1990 Bakshi and Stephanopoulos, 1993 third chapter of this volume, Koulouris et al), combine tasks 1 and 2 into one and solve the corresponding problems simultaneously. These methodologies utilize a priori defined general functional relationships between the operating data and process conditions, and as such they are not inductive. Nearest-neigh-... [Pg.213]

To detect adulteration of wine. Bums et al. (2002) found that the ratios of acetylated to p-coumaroylated conjugates of nine characteristic anthocyanins served as useful parameters to determine grape cultivars for a type of wine. Our laboratory utilized mid-infrared spectroscopy combined with multivariate analysis to provide spectral signature profiles that allowed the chemically based classification of antho-cyanin-containing fruits juices and produced distinctive and reproducible chemical fingerprints, making it possible to discriminate different juices. " This new application of ATR-FTIR to detect adulteration in anthocyanin-containing juices and foods may be an effective and efficient method for manufacturers to assure product quality and authenticity. [Pg.497]

The combined use of a continuous flow system and a spectrophotometer for sample screening to discriminate between synthetic and natural colorants is also available. With a very simple flow system on a column packed with natural materials, one can discriminate natural and synthetic colorants. The natural (not retained) ones can be determined in the first step and the synthetic (retained) ones in the second step after their elution. For yellow, red, green, blue, and brown, natural or synthetic colorants were chosen as models. The specific maximum wavelength for each color (400,530, and 610 mn, respectively) was selected by a diode array system. A complete discrimination of natural and synthetic colorants was obtained for concentrations of natural colorants (in the absence of synthetic ones) up to 2000 (yellow), 2000 (red), and 10,000 (brown) times that of the detection limits (DLs) of synthetic additives. This method was applied to screen fruit drinks and candies. ... [Pg.539]

Only controls using inhibitors of microbial growth are possible for microcosm experiments, and these may be impractical for outdoor systems, which therefore combine and may fail to discriminate abiotic and biotic reactions. [Pg.259]

Radke et al. [28] described an automated medium-pressure liquid chromatograph, now commonly called the Kohnen-Willsch instrument. At present, the method is widely used to isolate different fractions of soluble organic matter (for instance, as described in Reference 29 to Reference 31). A combination of normal phase and reversed-phase liquid chromatography has been used by Garrigues et al. [32] to discriminate between different aromatic ring systems and degrees of methylamine in order to characterize thermal maturity of organic matter. [Pg.372]


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See also in sourсe #XX -- [ Pg.183 ]




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