No abstract

It is common in modern manufacturing to simultaneously monitor more than one process quality characteristic. In such a multivariate scenario, the monitoring of the covariance matrix, along with the mean vector, plays an important role in assessing whether a process stays in control or not. However, monitoring the covariance matrix is technically more difficult, especially when there is only one observation available in each subgroup, disabling the usual sample covariance matrix as an effective estimator. To monitor the covariance matrix with individual observations in Phase II stage, several exponentially weighted moving average (EWMA) control charts have been constructed based on the distance between the estimated process covariance matrix and its target value.In this paper, two new control charts are devised using the sum of the square roots of the absolute deviations and its combination with the sum of squared deviations. These distance-based control charts are compared via the simulation experiments on different simulated out-of-control covariance matrices with respect to the number of quality characteristics being monitored, the shift pattern, and the shift magnitude. The simulation results identify the control charts that perform relatively robust and show that these various control charts may have their respective merits on different out-of-control scenarios.

Since the Analytic Network Process (ANP) was put forward, it has been widely applied in the many fields, such as conflict analysis, strategic planning. However, there are few applications of ANP relating to hospital management. This paper introduces ANP in the analysis of nosocomial infection and the evaluation of doctors' performance, which are two important aspects of hospital management. As a result, the main reasons of nosocomial infection can be identified and the performance of doctors can be systematically calculated, which will greatly benefit the hospital management.

Due to the aging of the population and the acceleration of the urbanization process, most of our country's rural areas have entered the aging stage, and the proportion of the elderly population is increasing. Therefore, the cultivation of rural volunteers, especially the elderly volunteers, is a key step for rural communities to carry out voluntary service. This article will take the elderly in village X, Changling county, Jilin province as the research object, to make full use of the special features of the local elderly and explore their potential. The article will use the method of action research, let the elderly and social workers formulate and implement the plan together, explore the path for social workers to train rural elderly volunteers. We can fill in the vacancy of local volunteer service resources, reduce the dependence on foreign volunteers. On the one hand, the elderly can better realize their own values. On the other hand, they can actively deal with the aging rural areas.