Estimate definitions

Definitive estimates. Definitive cost estimates are the most time-consuming and difficult to prepare, but they are also the most accurate. These estimates require preparation of plot plans, detailed flow sheets, and preliminary construction drawings. Scale models are sometimes used. All material and equipment is listed and priced. The number of labor hours for each construction activity is estimated. Indirect field costs, such as crane rentals, costs of tools, and supervision, are also estimated. This type of estimate usually results in an accuracy of 5%. 

Grade A term indicating the nature of coal as mainly determined by the sulfur content and the amount and type of ash not recommended for use in coal resource estimations definitive statements as to the contents and types of sulfur and ash are preferable—statements indicating high, medium, or low grade are inappropriate without documentation see Quality. 

Source J. R. Polo. 1986. Cost Estimates Definitions, Types, Accuracies," IFDC Fertilizer Process Economics Training Program, June 1986. 

Detailed design is a complete design of the work, including preparation of all preliminary and final working drawings, specifications, procedures, sketches, and estimates. Definitive design normally includes... 

Over the years, several different theories have been developed as to the mode of action of adhesives, i.e., the mechanism of adhesion. They extend from the simple mechanical theory via the electrostatic and adsorption theory to the diffusion theory, these being the most important [6]. One feature common to all these theories is that, for some adhesion phenomena, these theories allow qualitatively satisfactory assertions to be made, but in other respects they fail totally and, in some cases, even lead to conflicting results. The adhesion of adhesive to an adherent, on which any joint is based, is clearly not a consistent and isolatable process [7] but a complex addition of various adhesion effects. Because the number of individual processes involved, apart from exceptions, is extremely difficult to estimate, definitive confirmation or rejection of individual theories is hardly possible. 

It should be emphasized that capital cost estimates using installation factors are at best crude and at worst highly misleading. When preparing such an estimate, the designer spends most of the time on the equipment costs, which represent typically 20 to 40 percent of the total installed cost. The bulk costs (civil engineering, labor, etc.) are factored costs which lack definition. At best, this type of estimate can be expected to be accurate to 30 percent. 

The area can be measured from a map. Figure 6.1 clarifies some of the reservoir definitions used in reserves estimation. 

The basic condition of the Standard application - the availability of stable coupled probabilistic or the multiple probabilistic relations between then controlled quality indexes and magnetic characteristics of steel. All the probabilistic estimates, used in the Standard, are applied at confidence level not less than 0,95. General requirements to the means of control and procedure of its performance are also stipulated. Engineers of standard development endeavoured take into consideration the existed practice of technical control performance and test at the enterprises that is why the preparation of object control for the performance of nondestructive test can be done during the process of ordinary acceptance test. It is suggested that every enterprise is operated in correspondence with direct and non-destructive tests, obtained exactly at it, for detailed process chart and definite product type, however the tests have long since been performed after development of the Standard displayed that process gives way to unification. 

In this figure the next definitions are used A - projection operator, B - pseudo-inverse operator for the image parameters a,( ), C - empirical posterior restoration of the FDD function w(a, ), E - optimal estimator. The projection operator A is non-observable due to the Kalman criteria [10] which is the main singularity for this problem. This leads to use the two step estimation procedure. First, the pseudo-inverse operator B has to be found among the regularization techniques in the class of linear filters. In the second step the optimal estimation d (n) for the pseudo-inverse image parameters d,(n) has to be done in the presence of transformed noise j(n). 

The ribs on the reinforcing are distinguishable and can be measured, along with the diameter of the reinforcing with an estimated accuracy of about 10%. The upper part of the film is slightly overexposed causing less clear definition of the reinforcing bars. 

After the definition of a reaction type, a scheme for the evaluation of the given reaction type can follow in the reaction rule. An entire hierarchy of evaluations can be implemented, from no evaluation at all to a full-fledged estimation of reaction kinetics [12 ... 

Uncertainty expresses the range of possible values that a measurement or result might reasonably be expected to have. Note that this definition of uncertainty is not the same as that for precision. The precision of an analysis, whether reported as a range or a standard deviation, is calculated from experimental data and provides an estimation of indeterminate error affecting measurements. Uncertainty accounts for all errors, both determinate and indeterminate, that might affect our result. Although we always try to correct determinate errors, the correction itself is subject to random effects or indeterminate errors. 

Athermal mixing is expected in the case of 61 - 62. Since polymers generally decompose before evaporating, the definition 6 = (AUy/V°) is not useful for polymers. There are noncalorimetric methods for identifying athermal solutions, however, so the 6 value of a polymer is equated to that of the solvent for such a system to estimate the CED for the polymer. The fact that a range of 6 values is shown for the polymers in Table 8.2 indicates the margin of uncertainty associated with this approach. 

In so doing we have omitted the nonnegative term 5 p a)ij,aij — a)f). Since satisfies (5.11), and because the coefficients Uijki,bijki have the positive definiteness property (5.10), the inequality (5.20) results in the estimate... 

To gain a proper perspective of the role of computed physical properties, the relationship between estimated and computed properties needs to be understood. A thorough reading of Horvath (25) permits formulation of the following definitions of estimating or computing properties. 

Estimates of the amount of natural gas available are made within the context of definitions and are subject to revision as definitions change, as additional information becomes available, as resources are consumed, or as undedyiag assumptions are altered. These definitions iaclude proved reserves where the resource is expected to be recoverable and marketable usiag known technology and prices probable reserves where a resource has been identified but not completely characterized and possible or potential gas where estimates are based on the available geological iaformation, historical trends, and previous successes. There are variations ia these definitions throughout the world. 

Foreign. The OECD/NEA and IAEA have issued annual reports on world uranium resources, production, and demand since the mid-1960s (2—6). NEA/IAEA data for reasonably assured and estimated additional resources at costs of 80 and 130/kg uranium are given in Table 2 (21). These estimates incorporate data from both former world outside centrally planned economies (WOCA) and non-WOCA nations. A summary of other known uranium resources with and without cost range estimates is provided in Table 3 (22). These resources total about 1.4 x 10 t and include estimates that are not strictly consistent with standard NEA/IAEA definitions. 

No method has been devised to estimate with complete accuracy the amount of cmde petroleum that ultimately will be produced from the world s conventional oil and gas fields. Degrees of uncertainty, therefore, should be attached to all such estimates. These uncertainties can be expressed in several ways, the most important of which is achieved by dividing a resource into various categories. Several petroleum resources classifications have been proposed, and a comprehensive discussion of them (1), as well as the definition used in the assessment of the undiscovered resources of the United States (2), have been provided. Seven commonly used categories of resources are given here. 

In 1994, there were approximately six to seven dozen companies producing shicon in about 30 different Western countries, together employing several hundred furnaces. Nameplate Western world ferrosihcon capacity was estimated at 1,830,000 t of contained shicon. The effective capacity in 1994 was estimated at 1,450,000 t of contained shicon. There has been a definite shift in ferrosihcon capacity and trends for new plants and expansions are outside of the traditional supply areas. Since 1992, new capacity has been added in South Africa, Venezuela, Iran, and Bhutan. Additional plants near completion in Iran and Saudi Arabia are scheduled to start in 1996. The Western world ferrosihcon supply is expected to increase by about 150,000 t/yr of contained shicon by the year 2000 (27). 

The alkalinity is determined by titration of the sample with a standard acid (sulfuric or hydrochloric) to a definite pH. If the initial sample pH is >8.3, the titration curve has two inflection points reflecting the conversion of carbonate ion to bicarbonate ion and finally to carbonic acid (H2CO2). A sample with an initial pH <8.3 only exhibits one inflection point corresponding to conversion of bicarbonate to carbonic acid. Since most natural-water alkalinity is governed by the carbonate—bicarbonate ion equiUbria, the alkalinity titration is often used to estimate their concentrations. 

The systematic study of piezochromism is a relatively new field. It is clear that, even within the restricted definition used here, many more systems win be found which exhibit piezochromic behavior. It is quite possible to find a variety of potential appUcations of this phenomenon. Many of them center around the estimation of the pressure or stress in some kind of restricted or localized geometry, eg, under a localized impact or shock in a crystal or polymer film, in such a film under tension or compression, or at the interface between bearings. More generally it conveys some basic information about inter- and intramolecular interactions that is useful in understanding processes at atmospheric pressure as well as under compression. 

Time-Dependent Cascade Behavior. The period of time during which a cascade must be operated from start-up until the desired product material can be withdrawn is called the equiUbrium time of the cascade. The equiUbrium time of cascades utilizing processes having small values of a — 1 is a very important quantity. Often a cascade may prove to be quite impractical because of an excessively long equiUbrium time. An estimate of the equihbrium time of a cascade can be obtained from the ratio of the enriched inventory of desired component at steady state, JT, to the average net upward transport of desired component over the entire transient period from start-up to steady state, T . In equation form this definition can be written as... 

The fixed capital estimate depends on the definition of the plant. A grass-roots plant is a complete faciUty at a new location, including all utihties, services, storage faciUties, land, and improvements. If a process plant is located at an existing processing complex, it can usually share some of these auxihary faciUties. A battery-limits plant is defined as the process faciUty itself, so that the auxiUaries, off-site, and land-related items are excluded from the fixed capital estimation. However, a battery-limits plant maybe assigned allocated capital charges for the share of common utihty and service faciUties used by the plant. 

The accuracy of a fixed capital estimate tends to be a function of the design effort involved. As the project definition is refined, the estimates evolve from the various preliminary phases, ie, order of magnitude, predesign, factor estimates, etc, into the more detailed estimates used for budget authorization, project control, and contracts. At the same time, the uncertainty in the estimate decreases from 50% to as Htfle as 5%. 

Step Count Methods These methods, used for order-of-magnitude estimates, are based on the definition of the functional units required to carry out the process. A functional unit is a signifi-... 

Pumping and heat exchange form part of a functional unit. Tn-process storage is ignored, but large storage requirements for raw materials, intermediates, or products are usually estimated separately. Sometimes there are difficiilties in the identification and definition of the functional units involved in a process. 

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