For full accrual, just look up accrual accounting, that's basically it.
Modified Accrual Accounting is a governmental accounting method where revenue is recognized when it becomes available and measurable. Also, expenditure is typically recognized in the period in which the liability is incurred, except in cases where:
1. inventories of materials and supplies that may be considered expenditures either when bought or used
2. interest on general and special assessment long-term debt that is recognized on the date due; and
3. use of encumbrances, in which case, most governmental funds follow the modified accrual method.
Page 273, Dictionary of Accounting Terms, Baron's Business Guides, Baron's Educational Services, 1987 New York
A Cash Budget is a detailed budget of estimated cash inflows and outflows within a business, and incorporates both revenue and capital items.