In this paper, we present feedback control techniques for performing adaptive resource management in asynchronous real-time distributed systems. Asynchronous real-time distributed systems are characterized by significant execution-time uncertainties in the application environment and system resource state. Thus, such systems require adaptive resource management that dynamically monitor the syst...

Web services offer a possibility of exchanging data between entities from different organizational bounderies. Keeping sensitive resources private in a public world is a common concern of service providers. Thus, there is a need for access control management at the level of the web services in addition to a prior negotiation of access. This negotiation is the first step in the access control ma...

Role Based Access Control (RBAC) has received considerable attention as a model of choice for simplified access control over the past decade. More recently, risk awareness in access control has emerged as an important research theme to mitigate risks involved when users exercise their privileges to access resources under different contexts such as accessing a sensitive file from work versus doi...

The increasing availability of large and diverse datasets (big data) calls for increased flexibility in access control so to improve the exploitation of the data. Risk-aware access control systems offer a natural approach to the problem. We propose a novel access control framework that combines trust with risk and supports access control in dynamic contexts through trust enhancement mechanisms ...

In this paper, we develop new results concerning the risk-sensitive dual control problem for output feedback nonlinear systems, with unknown time-varying parameters. These results are not merely immediate specializations of known risk-sensitive control theory for nonlinear systems, but rather, are new formulations which are of interest in their own right. A dynamic programming equation solution...

background: these findings from several observational studies, investigated the association between red meat consumption and gliomas, were inconsistent. we conducted a systematic review and meta-analysis of observational studies to summarize available date on the relation between meat intake and risk of glioma. materials and methods: a systematic literature search of relevant reports published ...

We describe a framework for risk assessment specifically within the context of risk-based access control systems, which make authorization decisions by determining the security risk associated with access requests and weighing such security risk against operational needs together with situational conditions. Our framework estimates risk as a product of threat and impact scores. The framework th...

The importance of feedback control is being increasingly appreciated in quantum physics and applications. This paper describes the use of optimal control methods in the design of quantum feedback control systems, and in particular the paper formulates and solves a risk-sensitive optimal control problem. The resulting risk-sensitive optimal control is given in terms of a new unnormalized conditi...

Cara Williams is with the Labour and Household Surveys Analysis Divison. She can be reached at (613) 951-6972 or [email protected]. AN EMPLOYEE SITS AT HER DESK with numerous unread e-mail messages in her inbox, phone ringing, and a report to complete for the next morning. The demands of the job are making her anxious. At a nearby construction site, workers fear layoff as winter approache...

We consider the infinite-horizon optimal portfolio liquidation problem for a von Neumann-Morgenstern investor in the liquidity model of Almgren (2003). Using a stochastic control approach, we characterize the value function and the optimal strategy as classical solutions of nonlinear parabolic partial differential equations. We furthermore analyze the sensitivities of the value function and the...