Possibili temi per attività di tesi

Prof. Gianmaria DE TOMMASIEmail: detommas@unina.it

Napoli, 19 Dicembre 2018

UNINA

DIEII I

DIPARTIMENTO DI INGEGNERIA ELETTRICAE DELLE TECNOLOGIE DELL’INFORMAZIONE

VERSITA DEGLI STUDI DI

POLI FEDERICO II,

Outline UNINA

DIEII I

1 Analisi di SED modellati con reti di PetriNon-interferenzaOpacità

2 Controllo magnetico in tokamak

3 Altre attività

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Analisi di SED modellati con reti di Petri UNINA

DIEII I

Temi

Non-interferenza in SEDOpacità

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Non-interference UNINA

DIEII I

In system security it is important to prevent information leaksObjective: to prevent to an intruder to access to secretinformationDES have been used to model different information flowproperties

opacity (the secret is a state or a sequence)non-interference

Y.-C. Wu and S. Lafortune,Comparative analysis of related notions of opacity in centralized andcoordinated architectures,Discrete Event Dyn. Syst., vol. 23, no. 3, pp. 307–339, 2013

N. Busi and R. Gorrieri,A survey on non-interference with Petri nets,Lectures on Concurrency and Petri Nets, pp. 328–344, 2004

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Non-interference in PN systems UNINA

DIEII I

Two classes of users: high-level andlow-level usersA leak of information occurs when alow-level user (the intruder) obtainsinformation meant to be visible only tohigh-level usersBoth high-level and low-level usersknow the system structure, but theyinteract with the system in twodifferent ways (views)If the high-level view of the systeminterferes with the low-level one,information leaks may occur

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Risultati ottenuti e possibili attività UNINA

DIEII I

Risultati ottenuti (2017-2018)

Condizioni necessarie e sufficienti per verificare due diverseproprietà di non interferenzaL’approccio si basa sulla rappresentazione algebrica delle reti diPetriLe condizioni proposte si basano sulla soluzione di problemi ILPAlgoritmo per determinare l’insieme più piccolo di transizionidi alto livello da disabilitare offline per assicurare lanon-interferenza

Possibili temi di tesi

Estensione dei risultati di analisi alle reti etichettateDeterminazione di un algoritmo dinamico che assicurinon-interferenza a ciclo chiuso

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The opacity problem UNINA

DIEII I

Opacity in DES is related to the possibility of hiding a secret toexternal observers (the intruders)The secret can be either

a system state (initial, current, final)a sequence of events→ Language-based opacity (LBO)

Y.-C. Wu and S. Lafortune,Comparative analysis of related notions of opacity in centralized andcoordinated architectures,Discrete Event Dyn. Syst., vol. 23, no. 3, pp. 307–339, 2013

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Toy example UNINA

DIEII I

the secret sequence is abcc is the only observable event (whoseoccurrence can be directly measured)observing the single occurrence of c,an intruder will never no if either abcor bac occurredthe system is said to be opaque

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Risultati ottenuti e possibili attività UNINA

DIEII I

Risultati ottenuti (2017-2018)

Condizione necessaria e sufficiente per verificare lalanguage based opacity (LBO) in reti etichettateCondizione sufficiente (ma meno onerosacomputazionalmente) LBO

Possibili temi di tesi

Generalizzazione dell’approccio anche alla state opacityDeterminazione di un algoritmo dinamico che assicuriopacità a ciclo chiuso

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Nuclear Fusion for Dummies UNINA

DIEII I

Main AimProduction of energy by means ofa fusion reaction

D + T → 4He + n

Plasma

High temperature and pressure are neededFully ionised gas 7→ PlasmaMagnetic field is needed to confine the plasma

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Plasma magnetic control UNINA

DIEII I

In tokamaks, magnetic control of the plasma is obtained by means ofmagnetic fields produced by the external active coils

In order to obtain good performance, it is necessary to have a plasma withvertically elongated cross section ⇒ vertically unstable plasmas

It is important to maintain adequate plasma-wall clearance duringoperation

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The magnetic control problems UNINA

DIEII I

The plasma (axisymmetric) magnetic control in tokamaksincludes the following three control problemsthe vertical stabilization problemthe shape and position control problemthe plasma current control problem

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The plasma vertical instability UNINA

DIEII I

Simplified filamentary model

Consider the simplified electromechanical model with threeconductive rings, two rings are kept fixed and in symmetricposition with respect to the r axis, while the third can freelymove vertically.

If the currents in the two fixed ringsare equal, the vertical positionz = 0 is an equilibrium point for thesystem.

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Stable equilibrium - 1/2 UNINA

DIEII I

If sgn(Ip) 6= sgn(I)

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Stable equilibrium - 2/2 UNINA

DIEII I

If sgn(Ip) 6= sgn(I)

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Unstable equilibrium - 1/2 UNINA

DIEII I

If sgn(Ip) = sgn(I)

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Unstable equilibrium - 2/2 UNINA

DIEII I

If sgn(Ip) = sgn(I)

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Un’architettura flessibile per il controllomagnetico nei tokamak

UNINA

DIEII I

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Collaborazioni UNINA

DIEII I

Joint European Tokamak (Regno Unito)ITER OrganizationEAST (Repubblica Popolare Cinese)JT-60SA (Giappone)Fusion for Energy (UE)Max Planck IPP (Germania), IST-IPFN (Portogallo), SPC(Svizzera), . . .

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Figure: Shape comparisonat 22.5 s. Black shape (#81710without CLA), red shape(#81715 with CLA).

Figure: Currents in the divertor circuits.#81710 (reference pulse without CLA) andpulse #81715 (with CLA). The shared areascorrespond to regions beyond the currentlimits enforced by the CLA parameters.

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A MIMO controller for plasma shape andheat flux integrated control at EAST

UNINA

DIEII I

Figure: Option #1 - integratedcontrol of plasma shape and fluxexpansion. Figure: Option #2 - integrated

control of plasma shape anddistance between null points.

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EAST architecture UNINA

DIEII I

The EAST architecture is compliant to the one proposed for ITER & DEMO

The control algorithms deployed within the EAST PCS do not satisfy therequirements needed to easily replace the shape controller

vertical stabilization is strongly coupled with plasma shapecontrolThe PF Coils current controller can be improved (betterdecoupling)

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ITER-like VS at EAST UNINA

DIEII I

UICref(s) =

1 + sτ1

1 + sτ2·(

Kv · Ipref ·s

1 + sτz· Zc(s) + KIC · IIC(s)

)

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Experimental results - 1/2 UNINA

DIEII I

Figure: EAST pulse #70799. During this pulse the ITER-like VS was enabled from t = 2.1 s for 1.2 s, and onlyIp and rc were controlled, while zc was left uncontrolled. This first test confirmed that the ITER-like VS verticallystabilized the plasma by controlling zc and IIC , without the need to feed back the vertical position zc .

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Experimental results - 2/2 UNINA

DIEII I

Figure: EAST pulses #70799 & #71423. Tuning of the controller parameters to reduce oscillations on zc .

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Possibili attività di tesi UNINA

DIEII I

Sviluppo di sistemi di controllo magnetico (design, analisi, ecc.)Sviluppo di sistemi di supervisione del PCSTecniche di fault detection e sviluppo di sistemi fault tollerantper diagnostiche magnetiche. . .

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Ulteriori possibili attività di tesi UNINA

DIEII I

Tesi presso aziende di automazione (province di Avellino,Salerno e Caserta)Tesi presso ST microelectronicsSviluppo di sistemi di controllo in ambito aeronautico (a partireda giugno/luglio 2019)

Stay tuned!

Tenete d’occhio le news sulla pagina www.automazione.it, lapagina FB e il profilo Twitter

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Possibili temi per attività di tesi

Prof. Gianmaria DE TOMMASIEmail: detommas@unina.it

Napoli, 19 Dicembre 2018

Now we are ready to start :)

UNINA

DIEII I

DIPARTIMENTO DI INGEGNERIA ELETTRICAE DELLE TECNOLOGIE DELL’INFORMAZIONE

VERSITA DEGLI STUDI DI

POLI FEDERICO II,