Experimental coded

It is not always necessary to write the specification before writing the code. Indeed, it isn t unusual to write some experimental code, and then go back and try to make sense of what you ve done. 

Laboratory tests of the compact 45 X 45 x 50 mm, 3 x 3 Ge array detector which was incorporated into the experimental coded mask telescope, have already been discussed in Skinner et al (1993a). Here we concentrate on the coded mask properties, and use a few of the flights results as examples. More extensive results and conclusions from the flight data can be found in Skinner et al (1994). 

In an ambitious study, the AIMS method was used to calculate the absorption and resonance Raman spectra of ethylene [221]. In this, sets starting with 10 functions were calculated. To cope with the huge resources required for these calculations the code was parallelized. The spectra, obtained from the autocorrelation function, compare well with the experimental ones. It was also found that the non-adiabatic processes described above do not influence the spectra, as their profiles are formed in the time before the packet reaches the intersection, that is, the observed dynamic is dominated by the torsional motion. Calculations using the Condon approximation were also compared to calculations implicitly including the transition dipole, and little difference was seen. 

Figure 10.1-5. Predicted versus experimental solubility values of 496 compounds in the test set by a back-propagation neural network with 32 radial distribution function codes and eight additional descriptors.

Beryllium and its salts are toxic and should be handled with the greatest of care. Beryllium and its compounds should not be tasted to verify the sweetish nature of beryllium (as did early experimenters). The metal, its alloys, and its salts can be handled if certain work codes are observed, but no attempt should be made to work with beryllium before becoming familiar with proper safeguards. 

A 2 factorial design with two factors requires four runs, or sets of experimental conditions, for which the uncoded levels, coded levels, and responses are shown in Table 14.4. The terms Po> Po> Pfc> and Pafc in equation 14.4 account for, respectively, the mean effect (which is the average response), first-order effects due to factors A and B, and the interaction between the two factors. Estimates for these parameters are given by the following equations... 

A wide variety of procedures have been developed to evaluate the performance of explosives. These include experimental methods as well as calculations based on available energy of the explosives and the reactions that take place on initiation. Both experimental and calculational procedures utilize electronic instmmentation and computer codes to provide estimates of performance in the laboratory and the field. 

Computer codes are used for the calculational procedures which provide highly detailed data, eg, the Ruby code (70). Rapid, short-form methods yielding very good first approximations, such as the Kamlet equations, are also available (71—74). Both modeling approaches show good agreement with experimental data obtained ia measures of performance. A comparison of calculated and experimental explosive detonation velocities is shown ia Table 5. 

S. M. Ah, "An Updated Version of Computer Code CORA II for Estimation of Corrosion Product Mass and Activity Migration ia PWR Primary Circuits and Related Experimental Loops," Eourth International Conference on Water Chemistry of Nuclear Systems, Bournemouth, U.K., Oct. 1986, pp. 107-109. 

The moderator material and optimum sizes, the extraction channel configuration, as well as the converter and reflector material and sizes, were determined using the MCNP-4B code and the steepest descent method to attain a maximum flux density of thenual neutrons at the position of an object to be studied. The calculated data were experimentally verified, which showed good agreement. 

The Brookhaven Protein Data Bank, PDB (http //www.pdb.bnl.gov), is the primary store of experimentally determined atomic coordinates of proteins. Each coordinate set has a unique identification code that can be... 

The Burchell model s prediction of the tensile failure probability distribution for grade H-451 graphite, from the "SIFTING" code, is shown in Fig. 23. The predicted distribution (elosed cireles in Fig. 23) is a good representation of the experimental distribution (open cireles in Fig. 23)[19], especially at the mean strength (50% failure probability). Moreover, the predicted standard deviation of 1.1 MPa con ares favorably with the experimental distribution standard deviation of 1.6 MPa, indicating the predicted normal distribution has approximately the correct shape. 

FPEtool is described in Deal (1995). No formal benchmarking has been performed, nor has any source code validation or validation against experimental data but the code is based on a number of experiments Notarianni (1993), Walton (1993), Nelson (1992), Peacock (1993b), Heskestad (1986) and Hinkley (1975). 

The concepts of the National Electrical Code (NEC) gronps and the Maxi-mnm Experimental Safe Gap (MESG) are important criteria in the selection and specification of dry type flame arresters. These are explained below. 

In the earliest applications of numerical methods for the computation of blast waves, the burst of a pressurized sphere was computed. As the sphere s diameter is reduced and its initial pressure increased, the problem more closely approaches a point-source explosion problem. Brode (1955,1959) used the Lagrangean artificial-viscosity approach, which was the state of the art of that time. He analyzed blasts produced by both aforementioned sources. The decaying blast wave was simulated, and blast wave properties were registered as a function of distance. The code reproduced experimentally observed phenomena, such as overexpansion, subsequent recompression, and the formation of a secondary wave. It was found that the shape of the blast wave at some distance was independent of source properties. 

Over the years, this concept was refined in several ways. A scale dependency was modeled by the introduction of scale-dependent quenching of combustion. The first stage of the process was simulated by quasi-laminar flame propagation. In addition, three-dimensional versions of the code were developed (Hjertager 1985 Bakke 1986 Bakke and Hjertager 1987). Satisfactory agreement with experimental data was obtained. 

This subject has received little attention in the context of pressure vessel bursts. Pittman (1976) studied it using a two-dimensional numerical code. However, his results are inconclusive, because the number of cases he studied was small and because the grid he used was coarse. Baker et al. (1975) recommend, on the basis of experimental results with high explosives, the use of a method described in detail in Section 6.3.3. That is, multiply the volume of the explosion by 2, read the overpressure and impulse from graphs for firee-air bursts, and multiply them by a factor depending on the range. 

Baker et al. (1975) compare computer-code predictions of fragment velocity from spheres bursting into a large number of pieces and with some experimental... 

---