Bottom-up estimating

This bottom-up estimate correlates with the sales expectations of some leading players DuPont, for example, announced in September 1999 that they expected 25 percent of their material sales to come from biotech-based products in 10... 

The bottom-up estimating method determine costs for each work package in the WBS. This requires a comprehensive WBS. The accuracy of the method is driven by the size of the single work packages. 

Micro-scaling or bottom up approach to quality costs, where it is possible to calculate the cost of losses involved in manufacture and due to returns and/or claims. This method requires a great deal of experience and relies on the availability of detailed cost data throughout a product s life-cycle. While this is a crucial activity for a business, it is also not a practical approach for estimating the quality cost for product in the early stages of product development. 

Naslund (2001) investigated a combined system with river water as base load and snow cooling as back up, for an industrial application. The cooling need was 1,500 kW at 5 °C and 1,500 kW at 15 °C, continuously. The needed snow amount was 78,800 ton, stored in a 120 x 100 x 3 m3(L x W x H) pond with water tight asphalt bottom. The estimated investment cost was about 950,000 A. 

Beusen AHW, Bouwman AF, Heuberger PSC, Van Drecht G, Van der Hoek KW (2008) Bottom-up uncertainty estimates of global ammonia emissions from global agricultural production systems. Atmos Environ 42 6067-6077... 

The overall goal can be derived in one of two ways it can either be based on the estimates from the due diligence - a top-down goal set by the companies management - or it can be built from the bottom up by the individual project teams. A pure example of either case is very rare in practice usually, a weak form of the top-down variety prevails, in which the compan/s management formulates objectives in cooperation with the relevant project staff. 

Because Raman spectmm stems from the bonds vibrations, it provides an intrinsic nano-probing and offers a bottom-up approach of nanostmctured materials that comes as a good complement to other techniques such as transmission electron microscopy. X-ray diffraction, and infrared, and Mossbauer spectroscopy. Since almost no sample preparation is needed, Raman technique [12, 13] is commonly used to investigate nanomaterials. This could provide the phase identification and, possibly, size estimation [14]. 

An experimental determination of reproducibility should also coincide with a theoretical calculation based on the known, or estimated, precision of the individual steps of the method. The so-called bottom up method as part of an uncertainty audit, is included in the principles of valid analytical measurement (YAM) [7-9],... 

Projected emissions from manufacturing industry were estimated from a combination of a bottom-up survey by ICF/BOC and top-down modelling of energy demand by ESRI. 

Total emissions from ETS sectors calculated based on official statistics (top-down approach) and based on the bottom-up approach differ by about 2%. The result of this comparison was taken as a confirmation that ETS emission estimation was correct. It was assumed that lower questionnaire emissions can result from the incomplete list of identified ETS installations and from differences in emission factors used in the inventory and in questionnaires. 

As discussed above, Table 12.1 compares the final results of bottom-up data collection with top-down analysis. The difference between the emissions estimated with these two approaches was about 2%, indicating that the data collected at the installation level were reliable and could be used to calculate allocation at the sectoral and installation levels. 

Activity changes for non-energy production sectors were defined based on results of bottom-up, market-oriented analysis. Production growth in these sectors is more dynamic and could reach yearly rates higher than 20% (see Figure 12.3). Future activities estimates were based on the current sector situation, market conditions and assessment of development potential. Wide consultations with sectors were performed. 

Vehicle cost estimates based on a detailed bottom-up analysis consistent with TIAX s automotive fuel cell costing study. 

Although the bottom-up approach can be applied to estimate the uncertainty of analytical methods, as shown in the previous example (in Section 9.3.1), significant difficulties can be encountered in practice. In the analysis of residues and contaminants in foods, the largest contributions to... 

Leung GN, Ho EN, Kwok WH, et ah, A bottom-up approach in estimating the measurement uncertainty and other important considerations for quantitative analyses in drug testing for horses, J. Chromatogr. A 2007 1163(1-2) 237-246. 

The effort and duration estimates should be developed from the bottom up, preferably by the persons responsible for their execution, in contrast to the top-down, high-level estimates prepared during the project definition phase. They should take into account past experiences with similar, standard processes, to the extent possible. As predictions, the estimates should be equally Ukely to be above or below the actual results rather than represent the minimum or maximum time. Figure 4 provides an example of task time estimates. 

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