Espera e abandono na fila M/M/n+G e variantes

Abstract

The M/M/n + G queueing model can be used to describe the behavior of a Call Center. This model has Poisson arrivals with rate λ, service times are exponentially distributed with rate µ, n agents and the client´s patience time has general distribution. The waiting in line could not exceed a time (patience) which has distribution G, and if it occurs, the client leaves the system. In this models, Mandelbaum and Zeltyn [2004] showed that there is a linear relationship between average waiting time in queue and the probability of abandonment if the distribution of patience is Exponencial. In this work, we study this relationship in the case of patience with mixed distribution (which has discret and continuous parts). Through mixed distributions we try to represent the user´s reaction to recorded messages reproduced periodically when they are waiting for service. We have used Mixed Exponencial and Mixed Uniform distributions and, in both of them, there is not a linear relationship between average waiting time in queue and the probability of abandonment. We observe that for the same arrival rate, the average waiting time in line for mixed distribution is smaller than Exponencial or Uniform distributions with the same parameters. Also, we study the effect on waiting time and abandonment of different distributions of service and we observe that it is more affected by the coefficient of variation and average that by the particular distribution chosen for service.

Health Professionals and Organizations Lack of Awareness Regarding the Information Technology Resources Usage in Front of Their Major Beneficiary: Patients

“…As Barbosa e Lisboa (2006) states, it was not an endogenous process, but better, a slow revolution from the outside to inside, thus an always difficult mutation to be equated by the new "feudal lords". Due to its health care background, its aseptic procedures, and natural convergence of health care professionals, hospitals started to be recognized by the community as the only place where efficiency and complete medical treatments were offered (OLIVEIRA, 2009).…”

“…On the authority of Oliveira (2009), the question remains where and which will be the next sector or activity to be "beheaded". According to Paes (2011), the answer is being configured and becoming clearer for the developed countries: for primary care.…”

“…Throughout one decade, around 70% of all primary care, will have as desired goal the outpatient procedure, whether it is in specialized clinic programs, Basic Health care Services, Emergency Medical Services, medical offices or even targeted towards "Home Care", care at the patient´s own house. Oliveira and Gonçalves (2009) reported that in August 2005, the largest hospital of Latin America, "Hospital das Clínicas" (HC) from São Paulo city, Brazil, initiated a transfer process of all their low complexity health services to 13 outpatient care units of the State and 14 São Paulo Counties. The HC hospital was delivering 1.5 million urgent care services per year.…”

“…The current number of web access for Brazil is of 83.4 million (BARBOSA, 2012). Oliveira (2009) considers that the web is causing an unavoidable and unstoppable modification.…”

“…Oliveira and Gonçalves (2009) also believed that hospital organizations have been passively accepting doctors´ imperial position to avoid digitalization of clinic protocols or any other medical record, since utilizing computers as a tool to "unclog the arteries of inefficiency" was and still remains an heretic solution for that fortified medical community (OLIVEIRA, 2009). Each professional works with his situational experience and within his professional context.…”