Andrea Signori

University of Milan

19Publications

7H-index

166Citations

Publications 19

Newest

#1Andrea Signori (University of Milan)H-Index: 7

Optimal control of a phase field system modelling tumor growth with chemotaxis and singular potentials

#1Pierluigi Colli (UNIPV: University of Pavia)H-Index: 26

#2Andrea SignoriH-Index: 7

Last.Jürgen SprekelsH-Index: 22

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A distributed optimal control problem for an extended model of phase field type for tumor growth is addressed. In this model, the chemotaxis effects are also taken into account. The control is realized by two control variables that design the dispensation of some drugs to the patient. The cost functional is of tracking type, whereas the potential setting has been kept quite general in order to allow regular and singular potentials to be considered. In this direction, some relaxation terms have b...

A distributed optimal control problem for a diffuse interface model which physical context is that of tumor growth dynamics is discussed. The system we deal with consists of a Cahn-Hilliard equation for the tumor phase coupled with a reaction-diffusion for an unknown species nutrient surrounding the tumorous cells. The cost functional we are considering possesses some objective terms and it also penalizes the long-time treatment and the big aggregations of tumorous cells. Let us underline that, ...

Boundary control problem and optimality conditions for the Cahn-Hilliard equation with dynamic boundary conditions

#1Pierluigi Colli (UNIPV: University of Pavia)H-Index: 26

#2Andrea SignoriH-Index: 7

Last.Andrea SignoriH-Index: 1

view all 2 authors...

This paper is concerned with a boundary control problem for the Cahn--Hilliard equation coupled with dynamic boundary conditions. In order to handle the control problem, we restrict our analysis to the case of regular potentials defined on the whole real line, assuming the boundary potential to be dominant. The existence of optimal control, the Fr\'echet differentiability of the control-to-state mapping between appropriate Banach spaces, and the first-order necessary conditions for optimality ar...

Optimal treatment for a phase field system of Cahn-Hilliard type modeling tumor growth by asymptotic scheme

#1Andrea SignoriH-Index: 7

We consider a particular phase field system which physical context is that of tumor growth dynamics. The model we deal with consists of a Cahn-Hilliard equation governing the evolution of the phase variable which takes into account the tumor cells proliferation in the tissue coupled with a reaction-diffusion equation for the nutrient. This model has already been investigated from the viewpoint of well-posedness, long-time behavior, and asymptotic analyses as some parameters go to zero. Starting ...

Optimality conditions for an extended tumor growth model with double obstacle potential via deep quench approach

In this work, we investigate a distributed optimal control problem for an extended phase field system of Cahn--Hilliard type which physical context is that of tumor growth dynamics. In a previous contribution, the author has already studied the corresponding problem for the logarithmic potential. Here, we try to extend the analysis by taking into account a non-smooth singular nonlinearity, namely the double obstacle potential. Due to its non-smoothness behavior, the standard procedure to charact...

#1Andrea Signori (University of Milan)H-Index: 7

This paper is intended to tackle the control problem associated with an extended phase field system of Cahn–Hilliard type that is related to a tumor growth model. This system has been investigated in previous contributions from the viewpoint of well-posedness and asymptotic analyses. Here, we aim to extend the mathematical studies around this system by introducing a control variable and handling the corresponding control problem. We try to keep the potential as general as possible, focusing our ...

#1Andrea Signori (University of Milan)H-Index: 7

Abstract Information-based models of the IPO decision suggest that going public before having generated revenues is inefficient. Still, 15% of firms going public in Europe have not reported revenues prior to the IPO. This paper investigates why these firms decide to conduct an IPO and examines whether the absence of revenues affects the outcomes of this decision. The evidence shows that zero-revenue firms go public to fund investments, mainly in the form of R&D. However, their shares are more un...

#1Andrea Signori (UCSC: Catholic University of the Sacred Heart)H-Index: 7

#2Silvio Vismara (University of Bergamo)H-Index: 20

The recent decline in IPO activity can be explained by the small firms' increasing preference for being acquired rather than growing independently. This paper sheds light on this explanation by focusing on the nature of the firms facing this decision and their potential merger synergies. First, the above explanation should be particularly true for Young Innovative Companies (YICs), which are often superior to incumbents in originating innovations but face greater difficulties in bringing them to...

#1Andrea Signori (UCSC: Catholic University of the Sacred Heart)H-Index: 7

#2Silvio Vismara (University of Bergamo)H-Index: 20

Using an augmented dataset with combined information from Crowdcube, Crunchbase, and Companies House, we study the population of 212 successfully funded initial equity offerings on the UK's largest crowdfunding platform Crowdcube from inception (2011) to 2015. We find that 18% of these firms failed, while 35% pursued one or more seasoned equity offerings in the form of either private equity injection (9%) or follow-on crowdfunding offering (25%), while three firms were acquired. Among the determ...

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