This paper is concerned with the analysis of a threshold policy for scheduling “readers” and “writers” in a multiserver system and a comparison of its performance with the FCFS policy. A writer must be processed singly, thus using all servers in the system, while readers can be processed concurrently, each using one server. Higher throughput and better response time can be achieved by increasin...

With the increase in information accessibility, security and privacy of data is a key concern, underscoring the need for managing security of system resources and objects in an enterprise. One of the most popular access control management approaches is to abstract security administration tasks by employing system and security policies [1]. While policy based security management approach offers ...

BACKGROUND Since the passage of Proposition 99, California's comprehensive tobacco control programme has benefited from a localised policy adoption process that allows for the innovation and diffusion of strong local tobacco control policies throughout the state. METHODS The policy adoption continuum is described in the context of California's smoke-free workplace movement, and the influence ...

Wave-based release policies are prevalent in warehouses with an automated sorter, and take different forms depending on how much waves overlap and whether the sorter is split for operating purposes. Waveless release is emerging as an alternative policy adopted by an increasing number of firms. While that new policy presents several advantages relative to waves, it also involves the possibility ...

This paper considers a multiple stopping time problem for a Markov chain observed in noise, where a decision maker chooses at most L stopping times to maximize a cumulative objective. We formulate the problem as a Partially Observed Markov Decision Process (POMDP) and derive structural results for the optimal multiple stopping policy. The main results are as follows: i) The optimal multiple sto...

Wang, Qihua. Ph.D., Purdue University, May 2009. Access Control Policy Management. Major Professor: Ninghui Li. Access control is the traditional center of gravity of computer security [1]. People specify access control policies to control accesses to resources in computer systems. The management of access control policies include policy specification and policy analysis. In this dissertation, ...

Every autonomous agent operating in realistic settings must deal with incomplete state information. Sensory limitations, due to hardware constraints and/or limited interpretation algorithms, introduce hidden states which can prevent the acquisition of optimal control policies for a given task. This paper addresses this problem within the dynamical systems framework. The idea is to treat the age...