3 resultados para (X)over-bar control charts
em Bucknell University Digital Commons - Pensilvania - USA
Resumo:
For virtually all hospitals, utilization rates are a critical managerial indicator of efficiency and are determined in part by turnover time. Turnover time is defined as the time elapsed between surgeries, during which the operating room is cleaned and preparedfor the next surgery. Lengthier turnover times result in lower utilization rates, thereby hindering hospitals’ ability to maximize the numbers of patients that can be attended to. In this thesis, we analyze operating room data from a two year period provided byEvangelical Community Hospital in Lewisburg, Pennsylvania, to understand the variability of the turnover process. From the recorded data provided, we derive our best estimation of turnover time. Recognizing the importance of being able to properly modelturnover times in order to improve the accuracy of scheduling, we seek to fit distributions to the set of turnover times. We find that log-normal and log-logistic distributions are well-suited to turnover times, although further research must validate this finding. Wepropose that the choice of distribution depends on the hospital and, as a result, a hospital must choose whether to use the log-normal or the log-logistic distribution. Next, we use statistical tests to identify variables that may potentially influence turnover time. We find that there does not appear to be a correlation between surgerytime and turnover time across doctors. However, there are statistically significant differences between the mean turnover times across doctors. The final component of our research entails analyzing and explaining the benefits of introducing control charts as a quality control mechanism for monitoring turnover times in hospitals. Although widely instituted in other industries, control charts are notwidely adopted in healthcare environments, despite their potential benefits. A major component of our work is the development of control charts to monitor the stability of turnover times. These charts can be easily instituted in hospitals to reduce the variabilityof turnover times. Overall, our analysis uses operations research techniques to analyze turnover times and identify manners for improvement in lowering the mean turnover time and thevariability in turnover times. We provide valuable insight into a component of the surgery process that has received little attention, but can significantly affect utilization rates in hospitals. Most critically, an ability to more accurately predict turnover timesand a better understanding of the sources of variability can result in improved scheduling and heightened hospital staff and patient satisfaction. We hope that our findings can apply to many other hospital settings.
Resumo:
We show that to each inner function, there corresponds at least one interpolating Blaschke product whose angular derivatives have precisely the same behavior as the given inner function. We characterize the Blaschke products invertible in the closed algebra H-infinity[(b) over bar : b has finite angular derivative everywhere. We study the most well-known example of a Blaschke product with infinite angular derivative everywhere and show that it is an interpolating Blaschke product. We conclude the paper with a method for constructing thin Blaschke products with infinite angular derivative everywhere.
Resumo:
The response of some Argentine workers to the 2001 crisis of neoliberalism gave rise to a movement of worker-recovered enterprises (empresas recuperadas por sus trabajadores or ERTs). The ERTs have emerged as former employees took over the control of generally fraudulently bankrupt factories and enterprises. The analysis of the ERT movement within the neoliberal global capitalist order will draw from William Robinson’s (2004) neo-Gramscian concept of hegemony. The theoretical framework of neo-Gramscian hegemony will be used in exposing the contradictions of capitalism on the global, national, organizational and individual scales and the effects they have on the ERT movement. The ERT movement has demonstrated strong level of resilience, despite the numerous economic, social, political and cultural challenges and limitations it faces as a consequence of the implementation of neoliberalism globally. ERTs have shown that through non-violent protests, democratic principles of management and social inclusion, it is possible to start constructing an alternative social order that is based on the cooperative principles of “honesty, openness, social responsibility and caring for others” (ICA 2007) as opposed to secrecy, exclusiveness, individualism and self-interestedness. In order to meet this “utopian” vision, it is essential to push the limits of the possible within the current social order and broaden the alliance to include the organized members of the working class, such as the members of trade unions, and the unorganized, such as the unemployed and underemployed. Though marginal in number and size, the members of ERTs have given rise to a model that is worth exploring in other countries and regions burdened by the contradictory workings of capitalism. Today, ERTs serve as living proofs that workers too are capable of successfully running businesses, not capitalists alone.