Operational forecasts

Bates JM, Granger CWJ. The combination of forecasts. Oper Res Quart 1969 20 451-68. 

Bates Granger.1969. Combination of forecasts. Operations Research QiiarterlylO (4) 451-468. 

The capital cost estimates are generated by the Engineering function, often based on 50/50 estimates (equal probability of cost overrun and underrun). It is recommended that the operating expenditure is estimated based on the specific activities estimated during the field lifetime (e.g. number of workovers, number of replacement items, cost of forecast manpower requirements). In the absence of this detail it is common, though often inaccurate, to assume that the opex will be composed of two elements fixed opex and variable opex. 

The reservoir model will usually be a computer based simulation model, such as the 3D model described in Section 8. As production continues, the monitoring programme generates a data base containing information on the performance of the field. The reservoir model is used to check whether the initial assumptions and description of the reservoir were correct. Where inconsistencies between the predicted and observed behaviour occur, the model is reviewed and adjusted until a new match (a so-called history match ) is achieved. The updated model is then used to predict future performance of the field, and as such is a very useful tool for generating production forecasts. In addition, the model is used to predict the outcome of alternative future development plans. The criterion used for selection is typically profitability (or any other stated objective of the operating company). 

Important part of validation procedure is prognosis (on basis of Phai macopoeial requirements and results of inter-laboratory trials) of sample preparation, final analytical operation and total uncertainties. It enables to forecast method uncertainty in control laboratories. 

An attempt to forecast the further shrinkage of integrated circuits has been made by Gleason (2000). He starts out with some up-to-date statistics during the past 25 years, the number of transistors per unit area of silicon has increased by a factor of 250, and the density of circuits is now such that 20,000 cells (each with a transistor and capacitor) would fit within the cross-section of a human hair. This kind of relentless shrinkage of circuits, following an exponential time law, is known as Moore s law (Moore was one of the early captains of this industry). The question is whether the operation of Moore s Law will continue for some years yet Gleason says that attempts to forecast an end to the validity of Moore s Law have failed dismally it has continued to hold well beyond expectations . The problems at... 

Level A for Operational Safety Management updates the plant status for specific components that are out of service and forecasts the effect on core melt frequency using minimal cutsets generated in Level B. Code features include ... 

It will be necessary to forecast the amount of traffic to be generated by the development within the site and to propose a form of junction that not only deals with the site s traffic but also adequately caters for the existing traffic on the road. Tests for capacity are required and attention should also be given to the safety of operation of the proposed access. 

This type of lubrication provides the answer to why many mechanisms operate under conditions that are beyond the limits forecast by theory. It was previously thought that increasing pressure reduced oil film thickness until the aspirates broke through, causing metal-to-metal contact. Research has shown, however, that the effect on mineral oil of high contact pressure is a large increase in the viscosity of the lubricant. This viscosity increase combined with the elasticity of the metal causes the oil film to act like a thin solid film, thus preventing metal-to-metal contact. 

End of year Forecast sales 10 1 2 3 4 5t Forecast selling Price /t Raw material costs /t product Sale income less operating costs 106 Net cash flow 106 Cumulative cash flow 106 (Project NFW) Discounted cash flow at 15 per cent 106 Cumulative DCF (Project NPW) 106 Project NPW at 25 per cent discount rate Project NPW at 35 per cent discount rate Project NPW at 37 per cent discount rate... 

Efficient Consumer Response (ECR) and Collaborative Planning, Forecasting and Replenishment (CPFR) both are operations models in the consumer goods industry to ensure delivery capability and avoid stockouts based on an automated replenishment of outlets using product inventory, historic and/or planned sales information at the point-of-sales (POS). CPFR focuses on a close cooperation between retailer and manufacturer. ECR focus on the customer-facing reaction on customer responses in logistics, sales and promotions. 

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