Ricerc@Sapienza

An optimal control problem formulated to reduce the infection diffusion of an epidemic disease is solved in a locally linearised context. The approach has been driven by the necessity of using a state observer, since the state variable to be controlled is not directly measurable.

The control of the HIV infection is considered in the framework of the optimal control theory within the problem of resource allocation. A control action, changing the intervention strategy on the basis of the updated situations, is proposed. The switching instants are not fixed in advance but are determined along with the final control time. A constructive algorithm to compute iteratively the switching control is outlined. The solutions obtained provide interesting and promising results.

In this paper, a new model describing the human immunodeficiency virus (HIV)-acquired immuno deficiency syndrome (AIDS) epidemic spread is proposed. The improvement with respect to the known models has been driven by recent results obtained from historical data collection and the suggestions given by the World Health Organization: the characteristics of the virus diffusion, mainly by body fluids, imply the trivial fact that wise behaviors of healthy subjects and fast timely recognition of a new positive diagnosis should reduce the spread quite fast.

Agent supervision is a form of control/customization where a supervisor restricts the behavior of an agent to enforce certain requirements, while leaving the agent as much autonomy as possible. To facilitate supervision, it is often of interest to consider hierarchical models where a high level abstracts over low-level behavior details. We study hierarchical agent supervision in the context of the situation calculus and the ConGolog agent programming language, where we have a rich first-order representation of the agent state.

The world of machine-to-machine (M2M) communication is gradually moving from vertical single purpose solutions to multi-purpose and collaborative applications interacting across industry verticals, organizations and people - A world of Internet of Things (IoT). The dominant approach for delivering IoT applications relies on the development of cloud-based IoT platforms that collect all the data generated by the sensing elements and centrally process the information to create real business value.

An optimized system management of a commercial and industrial power system must take care of the actual operational and energetic duty of the power system distribution. A procedure based on the Arrhenius model of the Thermal Aging of Insulating Materials allows introducing the relative time coefficient (RTC) and promoting a heuristic method, as a rule of thumb, to estimate the life loss and the residual useful life for insulated power cables.

Contrary to many expectations, the development of smart (mini-)grids is slow, notwithstanding drastic improvements in innovative technologies, and the reasons for this are not strictly technical. The problem lies in regulatory barriers. Moreover, the current business models accommodate utilities more so than customers. Net metering is a key enabling factor for smart (mini-)grids. This article addresses the economic benefits of net metering for residential customers.

Buildings with mixed residential and commercial units show relevant power peak that are further increased by shifting from gas-driven systems to electric source. The proposed solution is to organize a microgrid for such type of buildings, aggregating different users with a common electric distribution system with a single connection to the grid, a local common generation and a common heating/cooling system (electric-driven). This approach upgrades a group of independent small users with rigid loads and chaotic behavior, to a large user with a flexible and controlled profile.

The energy policy approach is carrying out a long-time renewal process of the electric and in general energy framework. The energy spent in commercial, residential, and institutional buildings is a great amount (in EU is estimated about 40% of total energy consumption and about 90% in high-density urban areas) [1]. The general encouragement of the rational use of energy, also for residential users, introduced the new approach of the nearly zero-energy buildings (NZEBs) by the European energy performance of buildings directive (EPBD) [3].

In this article, we study the completion time of the PUSH-PULL variant of rumor spreading, also known as randomized broadcast.We show that if a network has n nodes and conductance φ then, with high probability, PUSH-PULL will deliver themessage to all nodes in the graph within O(logn/φ) many communication rounds. This bound is best possible. We also give an alternative proof that the completion time of PUSH-PULL is bounded by a polynomial in logn/φ, based on graph sparsification.