Budget method

Budget methods are based on the fact that there is a physiological upper limit to the amount of food and drink that can be consumed on any day. If the amount of additive present in that food is also limited (e.g. by national legislation) then there is an absolute maximum that can be ingested on any day. The assumptions in the budget method are extended to allow for the fact that only a proportion of the diet is likely to contain additives (Table 4.1).10 A conversion factor is produced which is used to derive the maximum use level from the ADI ... 

The method can also be used to provide a simple estimate of intake if maximum usage levels are known (the reverse budget method) ... 

Table 4.1 Figures most commonly used in the standard budget method...

Table 4.2 Food additives requiring further attention for adults or children following budget method screening10... 

It was recommended that the first step is to use a conservative, theoretical/hypothetical approach (such as the budget method) if no problems are encountered, then there is no need for further estimation. The next step would be a refinement of the intake estimate by undertaking a 3-day dietary study supplemented with a food frequency questionnaire to estimate percentage of consumers a minimum study population size would be 200 persons. If the intake estimate is stiU above the ADI, it would be necessary to carry out a risk assessment. 

How does activity-based budgeting differ from more traditional budgeting methods ... 

Although basically a very simple, low-budget method, it has been... 

Methods based on temporal gradients This approach is used at all scales, including small chambers operated in fully enclosed mode for short periods, boundary-layer budget methods in both the daytime convective boundary layer (CBL) and the nocturnal stable boundary layer (SBL), and global atmospheric budget methods. The dominant terms are I and IV. 

Budget methods. Vertical exchange rates and turbulent diffusivities Kz can be calculated from the heat balance or the mass balance of tracers for which transformation rates are known. Assuming horizontal homogeneity, the temporal change of tracer mass below a given depth z must be the sum of the net vertical mass flux through the cross-section at z and all sources and sinks of tracer mass below z. In the case of conservative tracers sources and sinks below z must be mass fluxes across the sediment-water interface. In the case of H, radioactive decay is an additional sink. In the case of He, tritium decay represents a source. If the increase of mass due to all sources and sinks, Sm, is known, the net mass flux can be calculated ... 

The budget method outlined above has been introduced by Jassby and Powell (1975) and applied successfully to determine Kz in numerous studies using heat as conservative tracer that can be measured easily by temperature sensors. However, especially in deep waters, in the surface layer, and during turnover the heat budget method is not reliable because temperature variations are too small to be measured accurately. In these cases the combined mass balance of Hetri and can be used to estimate exchange rates. 

In studies where the data are insufficient to calculate the temporal change of e.g., Hetri, water exchange can be estimated from the H- He ages, provided that the H- He ages agree with the isolation age. Then, the H- He age can be treated as ideal tracer for water age i which increases by 1 yr per yr. In case of steady state conditions, volume exchange between box 1 and box 2 can be calculated from the budget method (Eqn. 41) ... 

Figure 3,9 illustrates how three supply chain missions may make a differential impact upon activity centre/functional area costs and, in so doing, provide a logical basis for costing within the company, As a cost or budgeting method,... 

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