General discussion : central bank communication and policy effectiveness

Greenspan, Alan ; Monetary policy ; Banks and banking, Central

Optimization of armored spherical tanks for storage on the lunar surface

A redundancy strategy for reducing micrometeroid armoring mass is investigated, with application to cryogenic reactant storage for a regenerative fuel cell (RFC) on the lunar surface. In that micrometeoroid environment, the cryogenic fuel must be protected from loss due to tank puncture. The tankage must have a sufficiently high probability of survival over the length of the mission so that the probability of system failure due to tank puncture is low compared to the other mission risk factors. Assuming that a single meteoroid penetration can cause a storage tank to lose its contents, two means are available to raise the probability of surviving micrometeoroid attack to the desired level. One can armor the tanks to a thickness sufficient to reduce probability of penetration of any tank to the desired level or add extra capacity in the form of spare tanks that results in survival of a given number out of the ensemble at the desired level. A combination of these strategies (armoring and redundancy) is investigated. The objective is to find the optimum combination which yields the lowest shielding mass per cubic meter of surviving fuel out of the original ensemble. The investigation found that, for the volumes of fuel associated with multikilowatt class cryo storage RFC's, and the armoring methodology and meteoroid models used, storage should be fragmented into small individual tanks. Larger installations (more fuel) pay less of a shielding penalty than small installations. For the same survival probability over the same time period, larger volumes will require less armoring mass per unit volume protected

Economic Analysis of Supplemental Deductible Coverage as Recommended in the USDA's 2007 Farm Bill Proposal

A primary change to crop insurance contained in the USDA's Farm Bill Proposal is Supplemental Deductible Coverage (SDC). SDC would allow farmers who purchase individual crop insurance coverage to purchase GRP in the amount of the individual policy deductible. GRP indemnities would be accelerated compared with the current GRP policy. Analysis indicates that SDC provides substantial benefits in terms of certainty equivalent gains. The largest benefits are realized by low risk farmers, compared to others in the county, and farmers whose yields are highly correlated with the county yield. Optimal individual policy coverage levels generally decrease when SDC is taken.

Economic Analysis of Supplemental Deductible Coverage as Recommended in the USDA's 2007 Farm Bill Proposal

A primary change to crop insurance contained in the USDA’s Farm Bill proposal is supplemental deductible coverage (SDC). SDC would allow farmers who purchase individual crop insurance coverage to purchase area-wide coverage in the amount of the individual policy deductible. This supplemental area-wide coverage would be similar to the existing Group Risk Plan policy, but with an accelerated indemnity schedule. Analysis indicates that SDC increases farmer certainty equivalents. The largest benefits are realized by farmers with high yield potential in counties with greater systemic risk. In general, optimal individual policy coverage levels modestly decrease when SDC is taken.crop insurance, area-wide coverage, actual production history (APH), group risk plan (GRP), yield distribution, Risk and Uncertainty,

Two-dimensional convolute integers for optical image data processing and surface fitting

An approach toward low-pass, high-pass and band-pass filtering is presented. Convolution coefficients possessing the filtering speed associated with a moving smoothing average without suffering a loss of resolution are discussed. Resolution was retained because the coefficients represented the equivalance of applying high order two-dimensional regression calculations to an image without considering the time-consuming summations associated with the usual normal equations. The smoothing (low-pass) and roughing (high-pass) aspects of the filters are a result of being derived from regression theory. The coefficients are universal integer valves completely described by filter size and surface order, and possess a number of symmetry properties. Double convolution lead to a single set of coefficients with an expanded mask which can yield band-pass filtering and the surface normal. For low order surfaces (0,1), the two-dimensional convolute integers were equivalent to a moving smoothing average

Software management tools: Lessons learned from use

Experience in inserting software project planning tools into more than 100 projects producing mission critical software are discussed. The problems the software project manager faces are listed along with methods and tools available to handle them. Experience is reported with the Project Manager's Workstation (PMW) and the SoftCost-R cost estimating package. Finally, the results of a survey, which looked at what could be done in the future to overcome the problems experienced and build a set of truly useful tools, are presented