Field data

The upper part of the overburden is continuously subject to a variety of natural processes, which include seasonal changes to the element contents and ratios of elements in sampled material. It is necessary to take these changes into account when interpreting the results. Therefore, certain observations must be recorded during the fieldwork. A special field form is normally designed for collecting the relevant data. Portable computers are recommended to avoid a potential source of error when transferring the data from the forms to computer files at the office. 

There is one obligatory observation that must be recorded at the sampling site— the location (coordinates) of the site. This is best achieved using a GPS device from which the data can be downloaded to computer files, thus avoiding errors caused by manual measurement and transcription. 

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The field points must then be fitted to predict the activity. There are generally far more field points than known compound activities to be fitted. The least-squares algorithms used in QSAR studies do not function for such an underdetermined system. A partial least squares (PLS) algorithm is used for this type of fitting. This method starts with matrices of field data and activity data. These matrices are then used to derive two new matrices containing a description of the system and the residual noise in the data. Earlier studies used a similar technique, called principal component analysis (PCA). PLS is generally considered to be superior. 

Pesticide Runoff Modeling. Obtaining the field data necessary to understand the potential mnoff of pesticides under a variety of conditions and sods would be an expensive and time-consuming process. As a result, a variety of simulation models that vary in their conceptual approach and degree of complexity have been developed. Models are influenced by their intended purpose, the biases of the developer, and the scale at which they are used. 

One of the relationships iised to obtain Figure 7 was that between the amount of organic nitrogen in the soil, kg ha and the time, t yr, from the ploughing out of the permanent grassland. This was an exponential relationship derived by fitting to field data. ... 

A powerhouse (thermal) application is the most stringent application, as discussed in Section 7.19. Based on field data collected from various installations by different agencies the general insulation failures observed may be attributed to the following. 

The factor 6 is a design parameter for all future reference. In fact, this empirical factor has been established over many years of experience and field data collected on the behaviour and performance of a motor in such an unfavourable operating condition. 

The prestrikes will give rise to voltage surges from 3 to 5 p.u. as discussed above and for which all the terminal and the interconnecting cables must be suitable. The following are Field data collected from actual operations to illustrate this phenomenon ... 

Drawing inferences from the literature available on the subject (see the further reading at the end of the chapter), based on laboratory tests, practical experience and the field data available, deratings for different configurations are shown in Table 28.7 which should be sufficient to account for the likely proximity effects... 

Expander performance will shift as plant conditions—such as gas flowrate, gas inlet, and discharge pressure—gas composition, and inlet temperature change. Calculation of expander diermal efficiency from field data is not accurate because expander discharge flow normally consists of two phases, gas and liquid. Efficiency calculations should always be cross-checked with the shaft power produced before any decision on expander performance is made. 

This standard gives methods and proeedures for speeifying the sound emissions of gas turbine installations for industrial, pipeline, and utility applieations. Ineluded are praetiees for making field sound measurements and for reporting field data. This standard ean be used by users and manu-faeturers to write speeifieations for proeurement, and to determine eom-plianee with speeifieation after installation. Information is ineluded, for guidanee, to determine expeeted eommunity reaetion to noise. 

Normal upper limit of standard design range design for vaporization above this level should be handled with caution. Maximum if field data are available. 

The LER-HEP method (NUREG/ CR-3519) is a means of analyzing field data to estimate HEPs. It considers available data on specific human errors in similar to those being considered in the risk as.sessment. The application of the method in NUREG/CR-3519 is to the Licensee Event Report (LER) file so it is called the LER-HEP method. For each error analyzed by this method, an error rate is derived by dividing the number of similar errors by the estimated number of... 

SLAB calculates chemical concentrations at positions downwind and heights above the ground. Tlic plume may be denser-than-air, neutrally-buoyant, or less dense than air. Thermodynamics effeci.s are accounted for, including latent heat exchanges due to the condensation or evaporation ot liquids, Time averaged results may be calculated. SLAB is the easiest of the publicly-available dense gas models to set up and mn. It has been extensively validated against large-scale field data. 

Beare, A. N. et al., Criteria for Safety-Related NPP Operator Actions Initial Simulator Field Data Calibration, February 1983. 

Another method is a series of exhaust dilution equations based on Wilson and Lamb " and a series of earlier papers summarized in ASHRAE. This method is based on wind tunnel tests on simplified buildings and is intended to provide conservative (low dilution) results. Wilson and Lamb compared the model to actual field data collected at a university campus and found that the model did indeed predict dilutions similar to measured worst-case dilutions suitable for a screening model. However, many cases resulted in conservative Linderpredictions of dilutions. ... 

Higson, R. L., R. F. Griffiths, C. D. Jones, and D. J. Hall. 1994. Concentration measurements around an isolated building A comparison between wind tunnel and field data. Atmospheric Environment, vol. 28, no. 11, pp. 1827-1836. 

Where field data were imavailable, a program of experimental work (for example, based on the use of simulators for control room operations) could be implemented to generate appropriate generic data. 

The method of Buthod has given unusually good checks with data from industrial units. In general this method appears to give results that are slighdy higher than field data but not as high as the other methods presented previously. For shell-side pressure drop ... 

Compute the dip angle of the magnetic field vector after correction for the drill collar field, it should check with the local magnetic field data. What do you conclude if it does not ... 

In many engineering studies, field data are used which consist of failure times for failed units and differing current mnning times for unfailed units. Such data arise because units are put into service at different times and receive different amounts of use. 

To calculate the anode resistance a knowledge of the environmental resistivity is required. For submerged anodes the water resistivity can be obtained from graphical representations such as Fig. 10.19, provided that the temperature and water density are known. However, field data are preferable and, in the case of soils that have widely varying resistivities, they are essential. 

Munition Plant Modernization Program. Both the US Army and the Navy have extensive plant modernization and pollution abatement programs planned and underway, and the waste-water picture is changing rapidly. So rapidly, in fact, that field data are out of date by the time they can be put into a report. Perhaps the best way to present the story is to force-fit all information into one of three time eras ... 

The spectra of Pu3+ LaCl3 (29) and isostructural PUCI3 (30) have been examined and the energy-level analysis has been refined using extensive crystal-field data. Consequently, the results included in Table IV are well established. As already indicated, they serve as one basis for estimating parameters for higher-valent species. 

The values of K° seem to confirm the correlations of the earlier field data tnat the adsorption onto sediments does not vary by more than an order of magnitude in systems with low DOC. 

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