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91.
Simkins CE 《Development Southern Africa》1988,5(4):406-419
"This study surveys the policy issues associated with urbanization following the abolition of the pass laws [in South Africa]. The demographic background is briefly sketched. Using neo-classical analysis as a starting point, particular attention is paid to the present inefficiencies of city form associated with segregation. It is argued that current planning procedures are in danger of perpetuating or even worsening the situation. Obstacles to employment generation are considered and transport, local government and housing issues are discussed. On every front, urbanization policy is unstable and, even in the short term, there will be pressures to change it." 相似文献
92.
"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
93.
The critical state of the hospital industry, as previously described, generates a difficult decision environment for the materiel manager and those in the purchasing function. The unique life- and death circumstances of hospitals impose a further onus on those who manage them. In the name of saving lives, they can find a convenient excuse to disregard all moral principles, forgetting the Socratic dictum "it is not enough that one lives, but that one lives well." Without the moral "right stuff," they can easily give in to the seductions of momentary gains and glory through ethical short-cuts. There is wisdom and consolation in the words that "nice guys may appear to finish last, but usually they're running in a different race." Studies have established a direct relationship between corporate excellence and ethical values. The reality of competition in the hospital industry dictates that the integration of ethics into the life of the organization should happen by design and not by accident. This is what is meant by strategy. If hospitals would strive for excellence to survive and grow, they should have a strategy with a mission statement that also embodies its moral values and moral agenda. Such an approach does not guarantee that an organization will become immune to moral contamination, but it does provide an antidote. 相似文献
94.
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
95.
Faltermayer E 《Fortune》1992,126(14):84-88
Memo to Clinton's transition team: forget those tough expenditure ceilings you're considering. Look instead at what managed competition is already accomplishing. 相似文献
96.
In this paper, we discuss the properties of preliminary test estimators (PTE) of the parameters of simple linear model with
measurement error (ME model) when the slope of the linear model is suspected to be zero. Expressions of the bias, MSE and
efficiencies are obtained under conditional as well as unconditional situations with known reliability coefficient. Conditional
model results are compared to the standard model without measurement error. We also provide the unconditional model analysis
in finite samples. Asymptotic theory under local alternatives is developed when the variance of measurement error or the ratio
of the variance of the model error relative to the variance of the measurement error is known. Asymptotic expressions of bias
and MSE of the estimators along with their efficiencies are obtained. In every case, it is shown that the measurement error
tend to increase the variability of the estimators compared to the estimators without measurement error. Graphs and tables
are provided to see these results and to determine optimum level of significance for minimum guaranteed efficiency.
Received October 2001
RID="*"
ID="*" A. K. Md. E. Saleh is a Distinguished Research Professor and H. M. Kim is a Ph.D. candidate in the School of Mathematics
and Statistics, Carleton University, Ottawa.
Acknowledgment. The authors gratefully acknowledge the constructive suggestion of the referees to improve the paper. The research is supported
by NSERC grant A3088. 相似文献
97.
A bstract . A simple framework is presented for the analysis of the local employment, income, sales , and local government impacts of landing North Sea gas at either of two Norwegian kommunes (municipalities). These impacts indicate the different forms of economic change arising from a major economic development event. The average annual net change in these economic measures is estimated for the operational phase of a gas terminal. The analysis indicated substantial differences in local and regional net gains. Both sites yielded positive neteconomic gains, which means noneconomic and national considerations become key decision determinates. These national issues provide the setting to judge the local/regional net gains. The unresolved questions include the national benefits and costs of the landing decision given the small scale of the Norwegian economy, potential future gas finds, and a fully employed economy. 相似文献
98.
In this paper we present an effective algorithm for the construction and the identification of two-level nonisomorphic orthogonal
arrays. Using this algorithm, we identify and list a full catalogue of nonisomorphic orthogonal arrays with parameters OA(24,7,2,t), OA(28,6,2,t) and OA(32,6,2,t), t ≥ 2. Some statistical properties of these designs are also considered. 相似文献
99.
This empirical note extends the recent work by Holmes (2006) in examining the long-run relationship between private and public
savings in the U.S. over the post-World War II period. Standard Engle-Granger cointegration tests fail to reject the null
hypothesis of no cointegration; however, once allowance is made for an endogenous break in the cointegrating relationship,
the weak form of the Ricardian equivalence proposition is supported. 相似文献
100.
Many textbooks on project management present illustrations concerning the relative size of project attributes during different project phases. The derived models all have attributes in common, such as uncertainty, significance of decisions, and degree of freedom to maneuver, that are typically high in the beginning of the project and low in the end. At the same time, variables such as the accumulated cost and available information begin at low levels and end up at a high level at the end of the project. Based on empirical data from projects, this paper illustrates and quantifies one of these attributes, the freedom to maneuver, in different project phases. 相似文献