Cost analysis least

Net Present Worth Method The NPW method allows the conversion of all money flows to be discounted to the present time. Appropriate interest factors are applied depending on how and when the cash flow enters a venture. They may be instantaneous, as in the purchase of capital equipment, or uniform, as in operating expenses. The alternative with the more positive NPW is the one to be preferred. In some instances, the alternatives may have different lives so the cost analysis must be for the least common multiple number of years. For example, if alternative A has a 2-year life and alternative B has a 3-year hfe, then 6 years is the least common multiple. The rate of return, capitalized cost, cash flow, and uniform annual cost methods avoid this complication. 

All information used and/or developed for the estimate must be documented and kept at least until the project is completed and audited. This includes drawings, take-offs, preliminary sketches, vendor quotations, etc. The backup information is required for cost and scope tracking and control as well as final cost analysis. 

The results of this analysis are summarized in Figures 11a and 11b. The capital cost analysis indicates that the membrane system is very attractive compared to either alternative technology. Capital cost for the continuous centrifuges is at least four-fold higher, while the precoat filter is two-fold more costly. The cost per kilogram of enzyme produced, which includes all operating costs and capital depreciation over ten years, indicates that the membrane system can achieve the same separation at half the cost for centrifugation. 

The problem of solvent selection is relatively complex and a thorough treatment requires considerable information. In addition to basic liquid-liquid equilibrium data, knowledge of the phase densities, viscosities, and the liquid-liquid interfacial tension is also important. Moreover, the economics of IXE systems are often dominated by the solvent regeneration costs. If, for example, solvent regeneration b to be accomplished by extractive or azeotropic distillation, then vapor-liquM equilibrinm data for the ternary system must also be available. Insofar as the most interesting LLE systems ate often ffiose whidi are least ideal, the generation of a physical property data base to complete cost analysis is usually a sigruficant problem. 

In the Department of Defence, people were aware of the problem, saw the solution in building an underground passage for the main road, and made a corresponding agreement with the state government. However, in the process of planning the underpass, they became aware that it would cost at least CHF 7 million (equivalent to about U.S. 5 million). Therefore it was decided to perform a risk analysis of the situation and study cheaper alternatives [9]. 

Viability phase Basic concepts for reactor technologies, fuel cycle, and energy conversion processes, estahUshed through testing at appropriate scale imder relevant conditions, with all potential obstacles identified and resolved, at least in theory very preliminary cost analysis—preconceptual design, 10—25 years expected for viability phase. 

The scale of operations, accuracy, precision, sensitivity, time, and cost of methods involving redox titrations are similar to those described earlier in the chapter for acid-base and complexometric titrimetric methods. As with acid-base titrations, redox titrations can be extended to the analysis of mixtures if there is a significant difference in the ease with which the analytes can be oxidized or reduced. Figure 9.40 shows an example of the titration curve for a mixture of Fe + and Sn +, using Ce + as the titrant. The titration of a mixture of analytes whose standard-state potentials or formal potentials differ by at least 200 mV will result in a separate equivalence point for each analyte. 

The measure of assembly variability, q, derived from the analysis should be used as a relative performance indicator for each design evaluated. The design with the least potential variability problems or least failure cost should be chosen for further development. The indices should not be taken as absolutes as assembly variability is difficult to measure and validate. 

The Chemical Process Industry (CPI) uses various quantitative and qualitative techniques to assess the reliability and risk of process equipment, process systems, and chemical manufacturing operations. These techniques identify the interactions of equipment, systems, and persons that have potentially undesirable consequences. In the case of reliability analyses, the undesirable consequences (e.g., plant shutdown, excessive downtime, or production of off-specification product) are those incidents which reduce system profitability through loss of production and increased maintenance costs. In the case of risk analyses, the primary concerns are human injuries, environmental impacts, and system damage caused by occurrence of fires, explosions, toxic material releases, and related hazards. Quantification of risk in terms of the severity of the consequences and the likelihood of occurrence provides the manager of the system with an important decisionmaking tool. By using the results of a quantitative risk analysis, we are better able to answer such questions as, Which of several candidate systems poses the least risk Are risk reduction modifications necessary and What modifications would be most effective in reducing risk ... 

The next type of joint is weld overlays, which are often utilized to eliminate the need for costly thrust blocks [Fig. 4-2(p)]. In designing the pipe an analysis was made to ensure that it possessed sufficient longitudinal strength. It makes sense, then, to make the weld joints be at least as strong as the longitudinal strength of the pipe rather than just as an internal pressure-seal pipe. 

From this analysis it is clear that in addition to their benefits, the use of pesticides in food production not only causes serious public health problems but also considerable damage to vital agricultural and natural ecosystems in the United States and world. A conservative estimate suggests that the environmental and social costs of pesticide use in the United States total about 4 billion each year. Worldwide the yearly environmental and public health costs are probably at least 100 billion. This is several times the 18 bllllon/yr spent on pesticides in the world. 

With these findings we can conclude that the drug costs strongly increased since the introduction of HAART. However, other provider costs strongly declined with the introduction of this drug regime, so that the total costs remained stable or declined. HAART is - at least in the short-term analysis given in this literature review - cost-effective. 

An effective HE or cost-effectiveness analysis is designed to answer certain questions, such as Is the treatment effective What will it cost and How do the gains compare with the costs By combining answers to all of these questions, the technique helps decision makers weigh the factors, compare alternative treatments, and decide which treatments are most appropriate for specific situations. Typically, one chooses the option with the least cost per unit of measure gained the results are represented by the ratio of cost to effectiveness (C E). With this type of analysis, called a cost-effectiveness analysis (CEA), various disease end points that are affected by therapy (risk markers, disease severity, death) can be assessed by corresponding indexes of therapeutic outcome (mmHg blood pressure reduction, hospitalizations averted, life years saved, respectively). It is beyond the scope of this chapter to elaborate further on principles of cost-effectiveness analyses. A number of references are available for this purpose [11-13]. 

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