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991.
Miss Hazel Smith B.Econ. M.S.W. 《Australian Social Work》2013,66(2):25-29
This is a brief report on one aspect of a programme of applied research, in a large social welfare agency, designed to provide a basis for the evaluation of the policies, activities and structure of the agency. 相似文献
992.
993.
A decomposition technique for quantifying the impacts of changes in product mix and process performance on aggregate process-related indicators is presented. Through application of the technique, the real performance of a process can be quantified. Changes in real performance over time can be monitored to provide useful information for process evaluation and production planning. Two case studies, one related to the aggregate defective rate for an assembly line of an integrated circuit fabrication plant and the other to the aggregate inventory turnover for a tyre distribution company, are presented to illustrate the application of the technique. 相似文献
994.
Protective capacity is the 'extra' capacity placed at non-bottleneck resources to absorb random disruptions in planned levels of performance so that the bottleneck resource continues to be effectively utilized. A full factorial experiment with a simulation model was conducted to explore issues associated with the quantity and location of processing variance in a five-station manufacturing cell. The cell's performance was measured using both mean flow time ( MFT ) and bottleneck shiftiness ( SHIFT ) for 3 patterns of variance for the non-bottlenecks at 5 different levels of variation. In order to investigate the importance of the quantity of added capacity on the variation both a low level of protective capacity (10%) and a high level (50%) were considered. The results indicate that having the higher variation work centres close to the bottleneck provides reduced MFT and SHIFT . The performance measures improved at both the low and high setting of protective capacity. 相似文献
995.
Saieed F. Ateya 《Journal of applied statistics》2013,40(12):2720-2734
In this paper, the maximum likelihood (ML) and Bayes, by using Markov chain Monte Carlo (MCMC), methods are considered to estimate the parameters of three-parameter modified Weibull distribution (MWD(β, τ, λ)) based on a right censored sample of generalized order statistics (gos). Simulation experiments are conducted to demonstrate the efficiency of the proposed methods. Some comparisons are carried out between the ML and Bayes methods by computing the mean squared errors (MSEs), Akaike's information criteria (AIC) and Bayesian information criteria (BIC) of the estimates to illustrate the paper. Three real data sets from Weibull(α, β) distribution are introduced and analyzed using the MWD(β, τ, λ) and also using the Weibull(α, β) distribution. A comparison is carried out between the mentioned models based on the corresponding Kolmogorov–Smirnov (K–S) test statistic, {AIC and BIC} to emphasize that the MWD(β, τ, λ) fits the data better than the other distribution. All parameters are estimated based on type-II censored sample, censored upper record values and progressively type-II censored sample which are generated from the real data sets. 相似文献
996.
In robust parameter design, variance effects and mean effects in a factorial experiment are modelled simultaneously. If variance effects are present in a model, correlations are induced among the naive estimators of the mean effects. A simple normal quantile plot of the mean effects may be misleading because the mean effects are no longer iid under the null hypothesis that they are zero. Adjusted quantiles are computed for the case when one variance effect is significant and examples of 8-run and 16-run fractional factorial designs are examined in detail. We find that the usual normal quantiles are similar to adjusted quantiles for all but the largest and smallest ordered effects for which they are conservative. Graphically, the qualitative difference between the two sets of quantiles is negligible (even in the presence of large variance effects) and we conclude that normal probability plots are robust in the presence of variance effects. 相似文献
997.
In quality control, a performance variable having a two-sided specification limit is common for assessing lot quality. Sometimes it is difficult or impossible to measure the performance variable directly; for example, when testing is destructive, expensive, or when the performance variable is related to the lifetime of the product. However, it may happen that there are several concomitant variables which are easily measured and which correlate highly with the variable of interest. Thus, one may use measurements on these variables to select or screen product which will have a high conditional probability of meeting product specification. We consider this situation when all variables have a joint multivariate normal distribution and the specification limits on the performance variable are two-sided. 相似文献
998.
Harold S. Kaye M.S. Natalie B. Powell R.N. Regina F. Niedzwiecki B.S.N. Dorothy R. Stiles R.N. 《Journal of American college health : J of ACH》2013,61(2):74-78
Abstract An outbreak of Mycoplasma pneumoniae infection affected up to 110 students and employees at a college for deaf students (Gallaudet). After the introduction of M. pneumoniae onto the campus in late August 1977, the disease spread slowly among the students; the last documented case occurred in mid-December. A thorough review of chart records, mail surveys, a dormitory survey, and a three-month surveillance of the student health service provided an intensive look at the epidemiology and clinical spectrum of a mild to moderately severe disease in the epidemic setting. A matched-pair analysis demonstrated a more serious clinical illness among patients with M. pneumoniae than other patients presenting with febrile respiratory illness. Appropriate antimicrobial therapy appeared to suppress a high antibody response to M. pnuemoniae. A follow-up serosurvey one year after this outbreak demonstrated diagnostic titers to M. pneumoniae in 11 of 30 patients with confirmed infection in the original epidemic. 相似文献
999.
Abstract The purpose of licensing laws is to provide assurance of high quality service and to protect the public from incompetent practitioners. Safeguarding entrance to the professions by licensing examinations is one part of this responsibility which is entrusted to the professional boards. Assuring the continuing competence of practicing professionals is another part and a major challenge to every board of nursing throughout the United States. A 1979 mail survey identified 18 states which have specific continuing education requirements for relicensure of nurses. In addition, three states have standards of practice incorporated in the rules and regulations governing the nursing profession. Mandatory continuing education is a first step in the implementation of a system to assure the public of the continuing competency for practice of the professional nurse. It is acknowledgement, with the force of law, that continuous renewal of knowledge is a necessary condition for assuring competence. However, it is not sufficient in itself. Knowledge must be integrated in performance, which is the final test of competency. Thus, other system components that assure continuing competency must be developed and implemented. These include the identification of standards of acceptable performance, and the development and implementation of measures to evaluate practicing professionals and assure that they meet the performance standards. These measures include peer review, self-assessment, and recertification procedures. Successful implementation of a complete effective system will require the collaborative efforts of practicing nurses, their professional organizations, and the state boards of nursing. 相似文献
1000.
John Oeltmann MEd MSPH Todd W. Wilson MS CHES Nancy D. Brener PhD Carl V. Hill MPH 《Journal of American college health : J of ACH》2013,61(1):33-38
Abstract The authors examined the relationship between binge drinking and other substance use among US college students, using nationally representative data from the 1995 National College Health Risk Behavior Survey implemented by the Centers for Disease Control and Prevention. Compared with nonbinge drinkers, current binge drinkers were significantly more likely to report “ever” using and current use of cigarettes, marijuana, cocaine, and other illegal drugs. The researchers also found that the more often students binge drank, the more likely they were to have ever used cigarettes, marijuana, cocaine, and other drugs, and the more likely they were to report current use of cigarettes and marijuana. Those who design programs to prevent binge drinking and use of other substances should take into account the reality that many students use more than one substance and that the more frequently students report binge drinking, the more likely they are to be using other substances as well. 相似文献