Search results for "optimal"

The Burrows-Wheeler Transform between Data Compression and Combinatorics on Words

2013

The Burrows-Wheeler Transform (BWT) is a tool of fundamental importance in Data Compression and, recently, has found many applications well beyond its original purpose. The main goal of this paper is to highlight the mathematical and combinatorial properties on which the outstanding versatility of the $BWT$ is based, i.e. its reversibility and the clustering effect on the output. Such properties have aroused curiosity and fervent interest in the scientific world both for theoretical aspects and for practical effects. In particular, in this paper we are interested both to survey the theoretical research issues which, by taking their cue from Data Compression, have been developed in the conte…

Existence and Optimality of Nash Equilibria in Inventory Games

2005

Abstract This paper studies the stability and optimality of a distributed consensus protocol for n -player repeated non cooperative games under incomplete information. At each stage, the players choose binary strategies and incur in a payoff monotonically decreasing with the number of active players. The game is specialized to an inventory application, where fixed costs are shared among all retailers, interested in whether reordering or not from a common warehouse. The authors focus on Pareto optimality as a measure of coordination of reordering strategies, proving that there exists a unique Pareto optimal Nash equilibrium that verifies certain stability conditions.

Noncooperative dynamic games for inventory applications: A consensus approach

2008

We focus on a finite horizon noncooperative dynamic game where the stage cost of a single player associated to a decision is a monotonically nonincreasing function of the total number of players making the same decision. For the single-stage version of the game, we characterize Nash equilibria and derive a consensus protocol that makes the players converge to the unique Pareto optimal Nash equilibrium. Such an equilibrium guarantees the interests of the players and is also social optimal in the set of Nash equilibria. For the multi-stage version of the game, we present an algorithm that converges to Nash equilibria, unfortunately not necessarily Pareto optimal. The algorithm returns a seque…

Retail pricing decisions and product category competitive structure

2010

This study addresses the use of demand forecasting techniques by retailers to support their decision making. Specifically, the authors propose a pricing decision support model for retailers to estimate optimal prices, whose output depends on the configuration of a supporting measurement model. The measurement model is a demand function that relates sales and prices within the category; optimal prices are those whose effects on demand and retail margins maximize the category's profitability. This investigation focuses particularly on the role of competitive structure, such that the authors consider two types of price competition asymmetries for demand forecasting: those depending on the bran…

An overview of semi-infinite programming theory and related topics through a generalization of the alternative theorems

1984

We propose new alternative theorems for convex infinite systems which constitute the generalization of the corresponding toGale, Farkas, Gordan andMotzkin. By means of these powerful results we establish new approaches to the Theory of Infinite Linear Inequality Systems, Perfect Duality, Semi-infinite Games and Optimality Theory for non-differentiable convex Semi-Infinite Programming Problem.

Are Anticoagulants and Antiplatelet Agents Important in Thoracic Surgery?

2020

The management of antithrombotic drugs (antiplatelet and anticoagulant agents) is a common challenging issue in patients undergoing thoracic surgery. The procedure can require the temporary interruption of these drugs because of their associated haemorrhagic risk, therefore assuming a thrombotic risk also. The assessment of the balance between both risks gives us their optimal management.

Comparative analysis of fibrinolytic properties of Alteplase, Tenecteplase and Urokinase in an in vitro clot model of intracerebral haemorrhage.

2020

Abstract Objective Hematoma lysis with recombinant tissue plasminogen activator (rtPA) has emerged as an alternative therapy for spontaneous intracerebral and intraventricular haemorrhage (ICH and IVH). However, the MISTIE III and CLEAR III trial failed to show significant improvement of favourable outcomes. Besides experimental and clinical trials revealed neurotoxic effects of rtPA. The demand for optimization of fibrinolytic therapy persists. Herein, we used our recently devised clot model of ICH to systematically analyse fibrinolytic properties of rtPA, tenecteplase and urokinase. Methods In vitro clots of human blood (size: 25 ml and 50 ml; age: 1.5 tenecteplase, 24 tenecteplase and 48…

Sustainability and tourist flow networks: a mean field bi-level optimization approach

The widespread acknowledgement of tourism as a strategic pillar for economic growth and development has boosted competitiveness among tourist destinations. This concept has been greatly emphasized during the current COVID-19 pandemic crisis. Nevertheless, the massive presence of tourists imposes the challenge of adopting sustainable tourism practices to balance economic prosperity opportunities with potential threats to the environment and local communities. There are many definitions for sustainability, but the most effective one is ``the capacity to endure'' [Emel et al, 1997]: from an economic perspective this leads to find an equilibrium between short and long-term objectives so that to…

2013

Abstract. It has become possible to retrieve the global, long-term trends of trace gases that are important to atmospheric chemistry, climate, and air quality from satellite data records that span more than a decade. However, many of the satellite remote sensing techniques produce measurements that have variable sensitivity to the vertical profiles of atmospheric gases. In the case of constrained retrievals like optimal estimation, this leads to a varying amount of a priori information in the retrieval and is represented by an averaging kernel (AK). In this study, we investigate to what extent the estimation of trends from retrieved data can be biased by temporal changes of averaging kernel…

A variant design of Tuned Mass Damper Inerter for reducing displacements of base isolated structures

2021

In this study an innovative passive control strategy, referred to as New Tuned Mass Damper Inerter (New TMDI), coupled with a base isolation system (BI), is presented with the aim of reducing displacements in base isolated structures subject to seismic actions. The proposed New TMDI employs the synergetic benefits of a recently developed non-traditional Tuned Mass Damper (known as New TMD) and an inerter device to achieve higher control performances in isolated structures. Specifically, the New TMD is a secondary mass system connected to the BI system by a spring and to the ground by a dashpot. In addition, in the New TMDI configuration, the inerter device is placed in parallel with the dam…