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Computer experimental process

The use of experimental X-ray vidicons, original technique of X-raying and computer image processing allowed to improve basic parameters of XTVI and to achieve higher defectoscopic sensitivity and greater thickness of X-rayed materials and products. [Pg.450]

Both the need to reduce experimental costs and increasing reHabiHty of mathematical modeling have led to growing acceptance of computer-aided process analysis and simulation, although modeling should not be considered a substitute for either practical experience or reHable experimental data. [Pg.139]

Filtration constants K and C can be experimentally determined, from which the volume of filtrate obtained over a specified time interval (for a certain filter, at the same pressure and temperature) can be computed. If process parameters are changed, new constants K and C can be estimated from Equations 14 and 15. Equation 16 may be further simplified by denoting tg as a constant that depends on K and C ... [Pg.166]

The realized mathematical model has been also applied for computation of processes in MHHP intended to increase or decrease of a temperature level [5, 8], It was found that to reduce discrepancy between experimental and calculated data it is... [Pg.847]

One. relation or an assembly of relations that contains the condition necessary to impose the absence of important differences between the computed outputs and experimental outputs. This relation or assembly of relations frequently contains the requirement of a minimal dispersion (variance) between computed and experimental process outputs. So we need to minimize the function ... [Pg.137]

In the modern age of medicinal chemistry, QSAR modeling remains one of the most important instruments of computer-aided drug design. Skillful application of various methodologies discussed in this chapter will afford validated QSAR models, which should continue to enrich and facilitate the experimental process of drug discovery and development. [Pg.71]

Adaptive control systems have been applied in chemical processes. The range of their applicability has expanded with the introduction of digital computers for process control. Several theoretical and experimental studies have appeared in the chemical engineering literature, while the number of industrial adaptive control mechanisms increases continuously. Most of the adaptive control systems require extensive computations for parameter estimation and optimal adjustment of controller parameters, which can be performed on-line only by digital computers. Therefore, we will delay any discussion on the quantitative design of such systems until Chapter 31, after we have studied the use of digital computers for control. [Pg.229]

Besides more research on hydrodynamics and mass transfer, there is a need for more experimental work with the express purpose of model validation. In such process studies, parameters need to be measured along the height of RD columns. Too often measurements are confined to feed and product stream conditions. Such data cannot serve as a reliable discriminant of computer-based process models. [Pg.238]

The structure of an expert system for the analysis of sheet metal formability is illustrated by Fig. 10 (Lee et al. 1988). Besides software packages of finite element analysis and CAD, computer-aided process design also requires databases with FLDs for various working conditions. Experimental testing is a very valuable input for these databases, but it is also rather expensive. [Pg.546]

The EXPERIMENT was conducted according to the principles of rule developing experimentation (RDE) (Moskowitz and Gofman, 2007). The study is set up on a computer at a central server. The test stimuli are sent by Internet e-mail invitation to respondents who opt into the study. The actual stimuli are set up on the respondent s own computer. The process is rapid, reducing the amount of waiting time, and ensuring that the respondent remains engaged. [Pg.521]

The use of computational methods has also been extended to understand the factors that make a-bond metathesis favorable. Ziegler et al. [15] investigated the ability of [Cp Sc—H] and [CpjSc—CHj] to undergo a-bond metathesis with the C—H bonds of methane, ethene, and ethyne. A barrier of 10.8 kcal/mol was computed for the exchange of the methyl substituent in [Cp ScGHj] complex, which correlates with the experimental process of Lu described earlier (11.7 kcal/mol). Lower barriers were computed for ethene and ethyne. The authors concluded that the o-bond metathesis in this system was favored due to greater s character and lower p character at the carbon atom included in the Sc-"R-"H "R moiety, which favors the directionality of the new a-bond formed. [Pg.719]

To overcome these difficulties, a numerical finite element method was proposed by Assael et al (1998), in order to solve the complete set of energy-conservation equations that describe the heat-transfer experimental processes. The ehoice of this particular numerical method was dictated by the high accuracy the method exhibits in computational heat transfer problems. Hence, two coupled partial differential energy-eonservation equations, one for the wire and one for the fluid, with appropriate boundary conditions, were solved. [Pg.240]

Straightforward and easy to handle, SEC provides first-hand information about the distribution of molar masses of the sample analyzed. The result of an analysis by SEC is typically a graph representing the response of a concentration-sensitive or molar mass-sensitive detector (y-coordinate) placed at the column exit as a function of elution time (x-coordinate). After acquisition of the raw experimental data, there is a computer-assisted processing step that transforms the elution times into elution volumes, the latter into molar masses, and the detector response into polymer concentration and mass fraction. Eigure 6.17 illustrates an SEC equipment. [Pg.195]

Despite the enormous success of the zeolite membrane, practical application in a larger scale is still limited. Several factors such as cost of membrane development, reproducibility, long-term stability, and the method for the preparation of the defect-free membrane restrict its implementation in the industry. Molecular simulations become a powerful tool to predict the catalytic behavior of zeolite [14]. Compared to the experimental process, it is rapid and convenient, is cost effective, can handle more complex systems within a reasonable period of time, and results to better understanding of the system. Many computer simulation methodologies have been employed to understand the physicochemical properties of zeolite such as adsorption characteristics [15], diffusion and permeation [16], catalytic reaction [17], and also the nature of the acidic site [18,19]. The main concern of this work is to design a membrane using computer simulation methodology. [Pg.24]

In the brute force method the responses are computed at various points of parameter space 0. Following the ideas of Box and Coutie (1956), this procedure can be viewed as computer experimentation for which the integration of Eqs. (2.2) is the process and the parameters of functions (2.2) are the controllable variables. The response sensitivities introduced in Section 7.3 become the effects of these variables and the estimation of them constitutes the objective of empirical modeling. [Pg.447]

The technique presented above has been extensively evaluated experimentally using ultrasonic data acquired from a test block made of cast stainless steel with cotirse material structure. Here we briefly present selected results obtained using two pressure wave transducers, with refraction angles of 45° and 0°. The -lOdB frequency ranges of the transducers were 1.4-2.8 MHz and 0.7-1.4 MHz, respectively. The ultrasonic response signals were sampled at a rate of 40 MHz, with a resolution of 8 bits, prior to computer processing. [Pg.92]


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