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121.
LetP be a probability measure on ℝ andI
x be the set of alln-dimensional rectangles containingx. If for allx ∈ ℝn and θ ∈ ℝ the inequality
holds,P is a normal distributioin with mean 0 or the unit mass at 0. The result generalizes Teicher’s (1961) maximum likelihood characterization
of the normal density to a characterization ofN(0, σ2) amongall distributions (including those without density). The m.l. principle used is that of Scholz (1980). 相似文献
122.
"A projection model based on a multivariate continuous state, stochastic process is presented. The model allows multiple time-varying covariates to be used so parameters can be estimated from time series information on health changes and mortality, and their interaction. Health changes are simulated by altering parameters controlling the age trajectory and diffusion of risk factor means, variances, and covariances....By increasing the information used in projections it may be possible to better (a) anticipate the state of health at extreme ages, (b) forecast changes in health at specific ages over time, (c) stimulate the effects of specific interventions, and (d) determine the sensitivity of outcomes to a range of interventions." 相似文献
123.
Beckwith W 《Hospital materiel management quarterly》1992,13(3):1-4
Heat pipe technology will have a significant impact on the power consumption of many manufacturing industries, the installation costs of new or replacement air conditioning systems, and on electric utility peak demands. 相似文献
124.
125.
Assessing and acquiring technology does not have to be chaotic, driven solely by price, clinical preference, and emotion. With the tools available, it can be distilled to a process of organized common sense, which results in maximum flexibility for the user and allows materiel managers to procure the best, most cost-effective equipment for the hospital. 相似文献
126.
Rogers JE 《Hospital materiel management quarterly》1992,14(1):63-78
The REF, C, and score are a means to give quantitative values for product performance. Other product variables defined as humidity control factor, shear control factor, differential temperature control factor, product life factor, and cost factor were not addressed as part of this study. Additional variables include delivery, maintenance, and warranties. These components can be added to the score in some weighted manner as they become clinically founded. Interface pressures and shears were not measured for beds that are gatched. Each product tested will have characteristics pertinent to its own design that must be addressed to minimize sacral and coccyx skin breakdown when subjects are in this posture because some pneumatic pads bottom out to give excessive sacral and coccyx pressure while others wrinkle when used in this position. This is of major concern when one considers that the coccyx is more susceptible to pressure than any other bony prominence. There may be some aversion to labeling support product performance because it will allow the purchaser to know what is being bought. This initial study indicates the feasibility of quantitating what all patients require: a valid interface support surface for each specific need. The user can be adequately informed before the purchase as to a product's merits without being influenced by the results of inadequate testing, referrals, or sales media influences. Although cushions, shoes, or other prosthetic/orthotic devices were not part of this study, it is appropriate to rate all these devices in a similar manner by simply comparing pressure relief attained to that desired, expressing the result as a percentage of the worst case, and then labeling the product accordingly. Those subjects with sensation can rate comfort as part of the overall score. For cushions, ischial tuberosity pressure relief can be expressed as a percentage of the maximum attainable relief. Metatarsal head relief during gait as well as during static testing can be measured, and claims can be made for shoes and sneakers. Where impact loads and shear forces are paramount, the score must comprise appropriate parameters. Similarly, amputee distal stump relief as a percentage of worst case could be specified by the fitter. Iliac crest relief as a percentage of worst case can also be specified by the fitter. In all instances the score is not a subjective rating but one that can be measured correctly. All body support products can be given an REF, C value, and score as well as other qualifying values where appropriate instrumentation and sufficient subject sampling is used. 相似文献
127.
128.
Connell JR 《Fund raising management》1992,22(12):24-27
As older Americans take a close look at their assets, promote their interest in unlocking the wealth accumulation in their U.S. Saving Bond holdings. Use careful planning and advice when promoting this gift strategy. 相似文献
129.
130.
Slomski AJ 《Medical economics》1992,69(20):218, 224, 226 passim