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Quantitative history

Diagnostic methods for chemical processes are broadly classified as ones that use process model, and ones that rely on process history data. And they are classified as qualitative ones and quantitative ones, respectively (Venkatasubramanian, 2000). This study suggests a new hybrid method based on signed digraph (SDG) in qualitative model-based methods, and partial least squares (or projection to latent structures, PLS) in quantitative history data-based methods. [Pg.443]

This study is about the fault diagnosis by the hybrid method of qualitative model-based method and quantitative history data-based method. The diagnosis is performed by the observation of measured value and predicted value by DPLS model built on the local causal relationships of SDG The proposed method has the advantages to improve diagnosis accuracy and resolution, and facilitate diagnosis of masked multiple-fault. [Pg.448]

On the achievements and shortcomings of Annales history, see II, Hexter, 1972 and II, Stoianovich, 1976. On the state of quantitative history, see II, Fogel, 1975 II, Sprague, 1978 II, Kousser, 1980 and II, Bogue, 1981. An International Symposium on Quantitative Methods in the History of Science was held at the University of California, Berkeley, in August, 1976 see II, Carroll, Sturchio, and Bud, 1976. II, Hahn, 1980, is a convenient guide to quantitative studies in the history of science and related fields. [Pg.5]

Erickson, 1975. Charlotte Erickson. Quantitative History (review diiXicleY. American HistoricalReview 80 351-365. [Pg.522]

History and Objectives of Quantitative Drug Design. In Hansch C, P G Sammes and J B lor (Editors) Comprehensive Medicinal Chemistry Volume 4. Oxford, Pergamon Press, pp. 1-31. emd H van de 1995. Chemometric Methods in Molecular Design. Weinheim, VCH Publishers. [Pg.736]

The focus of this section is the emission of ultraviolet and visible radiation following thermal or electrical excitation of atoms. Atomic emission spectroscopy has a long history. Qualitative applications based on the color of flames were used in the smelting of ores as early as 1550 and were more fully developed around 1830 with the observation of atomic spectra generated by flame emission and spark emission.Quantitative applications based on the atomic emission from electrical sparks were developed by Norman Lockyer (1836-1920) in the early 1870s, and quantitative applications based on flame emission were pioneered by IT. G. Lunde-gardh in 1930. Atomic emission based on emission from a plasma was introduced in 1964. [Pg.434]

Chemical analysis of the metal can serve various purposes. For the determination of the metal-alloy composition, a variety of techniques has been used. In the past, wet-chemical analysis was often employed, but the significant size of the sample needed was a primary drawback. Nondestmctive, energy-dispersive x-ray fluorescence spectrometry is often used when no high precision is needed. However, this technique only allows a surface analysis, and significant surface phenomena such as preferential enrichments and depletions, which often occur in objects having a burial history, can cause serious errors. For more precise quantitative analyses samples have to be removed from below the surface to be analyzed by means of atomic absorption (82), spectrographic techniques (78,83), etc. [Pg.421]

The history of the discovery of amino acids is closely related to advances ia analytical methods. Initially, quantitative and qualitative analysis depended exclusively upon crystallization from proteia hydrolysates. The quantitative precipitation of several basic amino acids including phosphotungstates, the separation of amino acid esters by vacuum distillation, and precipitation by sulfonic acid derivatives were developed successively duriag the last century. [Pg.271]

The introduction of synthetic materials into natural products, often described as adulteration , is a common occurrence in food processing. The types of compounds introduced, however, are often chiral in nature, e.g. the addition of terpenes into fruit juices. The degree to which a synthetic terpene has been added to a natural product may be subsequently determined if chiral quantitation of the target species is enabled, since synthetic terpenes are manufactured as racemates. Two-dimensional GC has a long history as the methodology of choice for this particular aspect of organic analysis (38). [Pg.65]

The FTA laboratory perspective notes The history of the technologies, as illustrated through primarily qualitative—but some quantitative—assessment in many case studies, has shown that when properly installed, a decrease in or elimination of scale formation will be found. The key here is properly installed. By this it is meant that a manufacturer or their qualified representative is responsible for equipment integration. ... [Pg.335]

Combustion has a very long history. From antiquity up to the middle ages, fire along with earth, water, and air was considered to be one of the four basic elements in the universe. However, with the work of Antoine Lavoisier, one of the initiators of the Chemical Revolution and discoverer of the Law of Conservation of Mass (1785), its importance was reduced. In 1775-1777, Lavoisier was the first to postulate that the key to combustion was oxygen. He realized that the newly isolated constituent of air (Joseph Priestley in England and Carl Scheele in Sweden, 1772-1774) was an element he then named it and formulated a new definition of combustion, as the process of chemical reactions with oxygen. In precise, quantitative experiments he laid the foundations for the new theory, which gained wide acceptance over a relatively short period. [Pg.1]

Tnte MS. History and objectives of qnantitative drng design. In Hansch C, Sammes PG, Taylor JB, editors, Quantitative drug design (Comprehensive Medicinal Chemistry, Vol. 4). Oxford Pergamon Press, 1990. p. 1-31. [Pg.370]

Model equations can be augmented with expressions accounting for covariates such as subject age, sex, weight, disease state, therapy history, and lifestyle (smoker or nonsmoker, IV drug user or not, therapy compliance, and others). If sufficient data exist, the parameters of these augmented models (or a distribution of the parameters consistent with the data) may be determined. Multiple simulations for prospective experiments or trials, with different parameter values generated from the distributions, can then be used to predict a range of outcomes and the related likelihood of each outcome. Such dose-exposure, exposure-response, or dose-response models can be classified as steady state, stochastic, of low to moderate complexity, predictive, and quantitative. A case study is described in Section 22.6. [Pg.536]

During the anodic polarization of platinum to potentials of about 3.0 V (RHE), one or several layers (but no more than three) of chemisorbed oxygen are formed, which sometimes are called the a-oxide of platinum. The limiting thickness of these layers is about 1.3 nm. They can be studied both by electrochemical methods and by ellipsometry. At more positive potentials phase-oxide surface layers, the p-oxides are formed. The quantitative composition and structure of these layers and the exact limits of potential for their formation depend on many factors composition of the electrolyte solution, time of polarization, surface history, and often remain unknown. [Pg.546]

A complete medical history and targeted physical examination are essential to correctly classify the type(s) of Ul present. It is important to assess the degree of annoyance due to symptoms of the patient during the assessment. The degree of annoyance to the patient may not correlate well with the results of quantitative tests such as symptom frequency/severity, use of... [Pg.806]

Taken as a whole, these observations show that parasite lines differ in an immune-dependent manner in their infection/expulsion kinetics. Furthermore, there is heritable variation in survival and fecundity in previously exposed hosts and quantitative variation in the immune response that selected parasite lines elicit. Again, taken as a whole, these observations have the necessary corollary that variation in these traits exists not only in laboratory-maintained isolates but also in helminth species in nature. The phenotypes under consideration here (infection/expulsion kinetics, survival, fecundity) are multifactorial life-history traits. Understanding the basis of variation in the components and interplay of these complex, immune-responsive phenotypes must be of crucial relevance to understanding the immunology of infections of parasitic nematodes. This is of particular relevance in view of current attempts to develop immunological methods of nematode control. [Pg.103]


See other pages where Quantitative history is mentioned: [Pg.2114]    [Pg.76]    [Pg.86]    [Pg.359]    [Pg.5]    [Pg.474]    [Pg.399]    [Pg.197]    [Pg.242]    [Pg.359]    [Pg.514]    [Pg.66]    [Pg.86]    [Pg.158]    [Pg.423]    [Pg.472]    [Pg.485]    [Pg.220]    [Pg.262]    [Pg.356]    [Pg.289]    [Pg.32]    [Pg.277]    [Pg.3]    [Pg.631]    [Pg.164]    [Pg.17]    [Pg.222]    [Pg.223]    [Pg.306]    [Pg.43]    [Pg.156]    [Pg.147]   
See also in sourсe #XX -- [ Pg.5 , Pg.6 ]




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