Cost data scope

This paper results from work completed in 1979 (and updated in 1980) to evaluate the emerging supply/demand, cost/price outlook for the fertilizer commodities phosphate rock, upgraded phosphates, sulfur, and sulfuric acid. Our purpose here is to publish, in part, our analysis of recent trends and events which impact on sulfur supply and demand, and to use these together with available production cost data to project price behavior for sulfur over the near term. Such projections are helpful to managers of large industrial firms as one of several tools available to them in making investment, contract, marketing, or other major decisions. This paper is necessarily limited in scope, and will attempt to summarize the world outlook with emphasis on the North American scene. 

The best inemals and the optimum values of pressure, vapor velocity, and reboil vapor ratio are those that permit production of heavy water at minimum cost. The initial cost of the plant depends on a number of factors including the total number of towers, the total amount of reboiler and condenser surface, and the total volume of tower internals. The principal operating cost is for power, which is proportional to total loss in availability of steam as it flows through the towers. A complete minimum-cost analysis requires knowledge of the unit cost of all the important cost components and is beyond the scope of this book. Design for minimum volume of tower internals or minimum loss in availability due to tower pressure drop and for minimum cost of these two important contributors to total cost can be carried out without complete unit-cost data and will be discussed. Because the same choice of reboil vapor ratio minimizes the number of towers, their volume, and the loss of availability within them, this reboil vapor ratio is close to that which leads to minimum production cost. An equation for this optimum reboil vapor ratio will now be derived, and expressions will be developed for the total volume of towers and the total loss in availability in towers designed for the optimum ratio. 

The economics of FGD systems are site-specific and should be evaluated on a case-bycase basis. Nevertheless, some idea of the overall economics of flue gas desulfurization can be gained from Table 7-10 which provides data on 34 different FGD processes compiled from two reports issued by the Electric Power Research Institute. This organization has emerged as the major compiler of cost data for F(H) systems. Care should be taken in using these data since costs are strongly affected by the assumed bases, including scope of items... 

Stand-alone computer systems, usually based on a personal computer (PC) or programmable logic controller (PLC), provide a separate computer system for each pilot plant. This allows for economical expansion for new units, separates pilot plants completely for maintenance and troubleshooting, and often has the lowest initial cost. Standardization can be a problem and software control, data gathering, and storage packages can be limited in size, scope, and capabiUty these are usually acceptable trade-offs. 

Expenditure on corrosion prevention is an investment and appropriate accountancy techniques should be used to assess the true cost of any scheme. The main methods used to appraise investment projects are payback, annual rate of return and discounted cash flow (DCF). The last mentioned is the most appropriate technique since it is based on the principle that money has a time value. This means that a given sum of money available now is worth more than an equivalent sum at some future data, the difference in value depending on the rate of interest earned (discount rate) and the time interval. A full description of DCF is beyond the scope of this section, but this method of accounting can make a periodic maintenance scheme more attractive than if the time value of money were not considered. The concept is illustrated in general terms by considering a sum of money P invested at an... 

The advantages to using MSDSs for chemical inventories are that MSDSs are publicly available and required by law. There is no extra cost or labour needed to supply them. The limitations to using MSDSs as a source of inventory data are that currently, in the United States, a standardized reporting format is not mandatory. MSDSs are not verified or audited and MSDS information can be incomplete and/or inaccurate. In addition, OSHA s definition of hazard does not include the broader scope of hazard used in green chemistry. Therefore, chemicals that are potential hazards from the green chemistry perspective but are not defined by OSHA as hazards, are not required to be identified on a MSDS. 

Fixed cost effects are included in most production network design models but scale and scope effects related to variable costs and learning curve effects lead to concave cost functions (cf. Cohen and Moon 1990, p. 274). While these can be converted into piecewise linear cost functions, model complexity increases significantly both from a data preparation perspective (see Anderson (1995) for an approach to measure the impact on manufacturing overhead costs) and the mathematical solution process. Hence, most production network design models assume linear cost functions ignoring scale and scope effects related to variable costs. 

The current scientific infrastructure to support the committee s research recommendations is severely limited. Improvements in research-related infrastructure are needed to support these recommendations and to enhance the value of biomonitoring activities. The infrastructure needs encompass enhancing laboratory capabilities, expanding the scope and utility of CDC s National Health and Nutrition Examination Survey (NHANES) data, maximizing the use of collected human samples, and fostering international biomonitoring collaboration. Many of these recommendations for infrastructure improvement are cost-effective because they rely on expansion of structures and activities that are already in place. 

A tentative data base has been established based upon surveys and interviews with criminalists, educators, scientists and manufacturers. Existing forensic material collections and data files have been located and evaluated. New proposed forensic material collection specifications have been developed including recommendations relating to size, scope and costs of development. The report, although not yet published,... 

As indicated when K = kXjjT0MCp was first introduced just before Eqn. (12), K is constant with respect to decisions within each feedwater heater or condenser, but is a variable with respect to associated costs. Thus, for example, the dimensionless cost k includes the cost of cooling water inlet filters in the case of the condensers—while for feedwater heaters it includes the cost of the bleed steam duct and tap required for the addition of a new heater. It also includes the cost of end effects (such as headers and water boxes) which will be added automatically to k when the non-linearity correction factors mentioned above are included. When all these corrections are considered, the results of Eqns. (A2) and (A3) appear to be in good agreement with the values found in well-optimized plants (such as the Wisconsin Electric Plant from which the data for this work was taken), but it is beyond the scope of this paper to pursue this matter further. 

Reliable stability data of the p-i-n solar cell itself are not easily obtained, especially for non-encapsulated cells or modules. One of these tests e.g. for EN/IEC 61646 certification of modules is the so-called damp-heat test (85°C, 85% humidity, up to lOOOh). Recent studies were performed by Stiebig et al. [50, 51] exposing different types of cells to harsh conditions. One of the most important results was the excellent stability of silicon thin film solar cells. Remarkably, this is also valid for small area modules even without encapsulation [52]. This is of high interest because costs and efforts for module encapsulation strongly depend on the inherent stability of the solar cells. As a more detailed treatment of this subject is beyond the scope of this chapter, the reader is referred to the original papers [50,51]. 

In short, the large number of multi-chemical, multi-media environmental measurements associated with hazardous waste investigations during the past few years are unprecedented in scope and complexity. The small community of specialists in the measurements field is being pushed to the limit to reduce the time and cost involved in such measurements and to improve the representativeness of the data that are collected and the accuracy of the data that are reported. 

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