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Standardization techniques

For homogeneous NDT data and repeatable inspection conditions successful automated interpretation systems can relatively easily be developed. They usually use standard techniques from statistical classification or artificial intelligence. Design of successful automated interpretation systems for heterogeneous data coming form non-repeatable, small volume inspections with little a-priori information about the pieces or constructions to be inspected is far more difficult. This paper presents an approach which can be used to develop such systems. [Pg.97]

The linear integral equation (5) is solved by a standard technique, including expansion of the unknown An z) by some basis functions and transformation of (5) into a matrix equation to... [Pg.128]

In this chapter, we look at the techniques known as direct, or on-the-fly, molecular dynamics and their application to non-adiabatic processes in photochemistry. In contrast to standard techniques that require a predefined potential energy surface (PES) over which the nuclei move, the PES is provided here by explicit evaluation of the electronic wave function for the states of interest. This makes the method very general and powerful, particularly for the study of polyatomic systems where the calculation of a multidimensional potential function is an impossible task. For a recent review of standard non-adiabatic dynamics methods using analytical PES functions see [1]. [Pg.251]

Although the problem of compilation of training and test datasets is crucial, unfortunately no de-faao standard technique has been introduced. Nevertheless, we discuss here a method that was designed within our group, and that is used quite successfully in our studies. The method is mainly addressed to the task of finding and removing redundancy. [Pg.220]

Direct property prediction is a standard technique in drug discovery. "Reverse property prediction can be exemplified with chromatography application databases that contain separations, including method details and assigned chemical structures for each chromatogram. Retrieving compounds present in the database that are similar to the query allows the retrieval of suitable separation conditions for use with the query (method selection). [Pg.313]

We shall initially consider a closed-shell system with N electroris in N/2 orbitals. The derivation of the Hartree-Fock equations for such a system was first proposed by Roothaan [Roothaan 1951] and (independently) by Hall [Hall 1951]. The resulting equations are known as the Roothaan equations or the Roothaan-Hall equations. Unlike the integro-differential form of the Hartree-Fock equations. Equation (2.124), Roothaan and Hall recast the equations in matrix form, which can be solved using standard techniques and can be applied to systems of any geometry. We shall identify the major steps in the Roothaan approach. [Pg.76]

Introduction. When only very small quantities of organic materials are available their manipulation must necessarily be carried out on a correspondingly small scale. This occurs frequently in research problems, but small-scale preparative work is often of value to the student because considerable economy of materials and of time can be achieved. It is emphasised, however, that the proper training for the organic chemist must rest upon the correct understanding and thorough practice of the manipulations on the macro-scale already described, and that he should consider small-scale work as a sequel to and not as a replacement of the above standard techniques. [Pg.59]

Rice, G. W. Determination of Impurities in Whiskey Using Internal Standard Techniques, /. Chem. Educ. 1987, 64, 1055-1056. [Pg.611]

As in the case of the salt complexation processes, the cryogenic systems require prepuriftcation of the feed gas. Bulk water, hydrogen sulfide, and carbon dioxide are removed by standard techniques. Final removal of these materials is accompHshed by adsorption. After prepuriftcation, the gases are ready for cryogenic processing. [Pg.55]

Bulk density is easily measured from the volume occupied by the bulk solid and is a strong func tion of sample preparation. True density is measured by standard techniques using liquid or gas picnometry Apparent (agglomerate) density is difficult to measure directly. Hink-ley et al. [Int. ]. Min. Proc., 41, 53-69 (1994)] describe a method for measuring the apparent density of wet granules by kerosene displacement. Agglomerate density may also be inferred from direcl measurement of true density and porosity using Eq. (20-42). [Pg.1877]

Auxiliary data are the sizes of bubbles and droplets. These data and the holdups of the two phases are measured by a variety of standard techniques. Interfacial area measurements utihze techniques of transmission or reflection of light. Data on and methods for finding sohi-bihties of gases or the relation between partial pressure and concentration in hquid are also well estabhshecT... [Pg.2109]

Standardized techniques atomic absorption (AAA) and photometric (FMA) of the analysis and designed by us a technique X-Ray fluorescence of the analysis (XRF) for metals definition in air of cities and the working areas of plants to production of non-ferrous metals are applied. The samples of aerosols were collected on cellulose (AFA-HA) and perchlorovinyl (AFA-VP and FPP) filters (Russia). The techniques AAA and FMA include a stage of an acid-temperature ashing of a loaded filter or selective extraction of defined elements from filter by approaching dissolvent. At XRF loaded filters were specimens. [Pg.207]

IEEE 4/1995 Relevant US standards ANSI/NEMA and IEEE Standard techniques for HV testing ... [Pg.453]

IEEE 4/1995 IEEE 1313.1/1996 Standard techniques for HV testing insulation coordination. Definitions, principles and rules ... [Pg.842]

This can be measured by injecting dust into a premixed flammable gas-air mixture so that the final gas concentration is known. Provided the gas does not condense when pressurized it is possible, with appropriate precautions, to inject the dust using a pressurized gas-air mixture identical to the mixture in the test vessel. This avoids concentration gradients. Because it is a non-standard technique the possibility of estimating the hybrid mixture MIE (HMIE) should be considered (6-1.3). [Pg.63]

Today dynamic SIMS is a standard technique for measurement of trace elements in semiconductors, high performance materials, coatings, and minerals. The main advantages of the method are excellent sensitivity (detection limit below 1 pmol mol ) for all elements, the isotopic sensitivity, the inherent possibility of measuring depth profiles, and the capability of fast direct imaging and 3D species distribution. [Pg.106]

Macrostrain is often observed in modified surfaces such as deposited thin films or corrosion layers. This results from compressive or tensile stress in the plane of the sample surface and causes shifts in diffraction peak positions. Such stresses can easily be analyzed by standard techniques if the surface layer is thick enough to detect a few diffraction peaks at high angles of incidence. If the film is too thin these techniques cannot be used and analysis can only be performed by assuming an un-... [Pg.216]

Nakamura, Takagi and Ueno have also utilized 4 -nitrobenzo-l 5-crown-5 as a starting material Their goal was the formation of a colored crown which could be utilized in transport studies. They have prepared 4 -picrylaminobenzo-l 5-crown-5 for this purpose in the following way. 4 -Nitrobenzo-l 5-crown-5 was hydrogenated and then picryl chloride was added. Nucleophilic aromatic substitution apparently ensued (deep red color) and the product was th n isolated by standard techniques as a yellow solid (mp 155°, max 395 nm) in 72% yield as shown in Eq. (3.17). [Pg.28]

For an existing process plant, the designer has the opportunity to take measurements of the fume or plume flow rates in the field. There are two basic approaches which can be adopted. For the first approach, the fume source can be totally enclosed, and a temporary duct and fan system installed to capture the contaminant. For this approach, standard techniques can be used to measure gas flow rates, gas compositions, gas temperatures, and fume loadings. From the collected fume samples, the physical and chemical characteristics can be established using standard techniques. For most applications, this approach is not practical and not very cost effec tive. For the second approach, one of three field measurement techniques, described next, can be used to evaluate plume flow rates and source heat fl uxes. [Pg.1269]

Statistical techniques can be used for a variety of reasons, from sampling product on receipt to market analysis. Any technique that uses statistical theory to reveal information is a statistical technique, but not all applications of statistics are governed by the requirements of this part of the standard. Techniques such as Pareto Analysis and cause and effect diagrams are regarded as statistical techniques in ISO 9000-2 and although numerical data is used, there is no probability theory involved. These techniques are used for problem solving, not for making product acceptance decisions. [Pg.547]

Both from the experimental or theoretical point of view, clusters studies present many difficulties due to their typical size (1-10 nm), usually larger than current systems studied in chemistry, but also too small for many physical standard techniques of characterisation and manipulation. [Pg.129]

When specifically labelled compounds are required, direct chemical synthesis may be necessary. The standard techniques of preparative chemistry are used, suitably modified for small-scale work with radioactive materials. The starting material is tritium gas which can be obtained at greater than 98% isotopic abundance. Tritiated water can be made either by catalytic oxidation over palladium or by reduction of a metal oxide ... [Pg.42]

Innumerable derivatives have been prepared by the standard techniques of organic chemistry. The organosilanes tend to be much more reactive than their carbon analogues, particularly towards hydrolysis, ammonoly-sis. and alcoholysis. Further condensation to cyclic oligomers or linear polymers generally ensues, e.g. ... [Pg.364]

In practice the finite-field calculation is not so simple because the higher-order terms in the induced dipole and the interaction energy are not negligible. Normally we use a number of applied fields along each axis, typically multiples of 10 " a.u., and use the standard techniques of numerical analysis to extract the required data. Such calculations are not particularly accurate, because they use numerical methods to find differentials. [Pg.289]

The standard technique for obtaining alkynylpyrazoles consists of mixing up the ether solutions of diazoalkane and diacetylene or its derivatives (or diazopropyne and acetylene) and keeping the reaction mixture either for several hours or for three weeks within a narrow temperature range (0-20°C) (Tables II and III). [Pg.6]

In our calculations we make use of several standard techniques of molecular dynamics simulations. The integration of the equations of motions is done by the velocity form of the Verlet-algorithm with a time step of 1.5 The temperature is controlled... [Pg.96]


See other pages where Standardization techniques is mentioned: [Pg.307]    [Pg.2672]    [Pg.770]    [Pg.40]    [Pg.1072]    [Pg.134]    [Pg.376]    [Pg.119]    [Pg.303]    [Pg.360]    [Pg.155]    [Pg.385]    [Pg.246]    [Pg.271]    [Pg.495]    [Pg.584]    [Pg.72]    [Pg.161]    [Pg.1072]    [Pg.146]    [Pg.399]    [Pg.75]    [Pg.758]    [Pg.503]    [Pg.802]   


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