Sensor Deployment for Network-like Environments

This paper considers the problem of optimally deploying omnidirectional sensors, with potentially limited sensing radius, in a network-like environment. This model provides a compact and effective description of complex environments as well as a proper representation of road or river networks. We present a two-step procedure based on a discrete-time gradient ascent algorithm to find a local optimum for this problem. The first step performs a coarse optimization where sensors are allowed to move in the plane, to vary their sensing radius and to make use of a reduced model of the environment called collapsed network. It is made up of a finite discrete set of points, barycenters, produced by collapsing network edges. Sensors can be also clustered to reduce the complexity of this phase. The sensors' positions found in the first step are then projected on the network and used in the second finer optimization, where sensors are constrained to move only on the network. The second step can be performed on-line, in a distributed fashion, by sensors moving in the real environment, and can make use of the full network as well as of the collapsed one. The adoption of a less constrained initial optimization has the merit of reducing the negative impact of the presence of a large number of local optima. The effectiveness of the presented procedure is illustrated by a simulated deployment problem in an airport environment

Ritornare all’affitto: evidenze analitiche e politiche pubbliche

La crisi ha contribuito a far emergere, in tutta la sua drammaticità, un disagio abitativo diffuso le cui cause strutturali vanno ricercate nelle dinamiche del mercato residenziale italiano degli ultimi trent’anni. La letteratura scientifica e l’accesa discussione pubblica si sono principalmente concentrate attorno alla fragilità delle politiche di edilizia residenziale pubblica e di social housing, le difficoltà di accesso al credito per l’acquisto di case e le problematiche relative al costo della locazione e al rinnovo dei contratti. La tesi che si sostiene in questo contributo è che per l’Italia sia auspicabile un “ritorno all’affitto” attraverso programmi e politiche pubbliche che si pongano l’obiettivo di un sostanziale cambio nei titoli di godimento dello stock abitativo. Il paper mette a fuoco le molteplici rigidità causate in Italia dall'eccesso di abitazioni occupate dai proprietari, fra cui: la ricchezza delle famiglie congelata in immobili e mutui, la scarsa mobilità territoriale, un’elevata soglia di accesso all’alloggio, l’indebitamento prolungato, la dipendenza dei figli dai genitori, il sottoutilizzo dello stock residenziale. Attraverso un’analisi della situazione anche di altri paesi europei dove negli ultimi anni si è registrata la diminuzione del peso delle case di proprietà sullo stock abitativo complessivo (fra cui l’Irlanda, la Spagna, l’Islanda, ovvero paesi colpiti fortemente dalla crisi) sono quindi discusse possibili politiche di ritorno all’affitto, che si pongano l’ambizioso traguardo del cambio del titolo di godimento dalla proprietà alla locazione per quattro milioni di unità abitative su scala nazionale in dieci anni

Handbooks in planning: five theses for teaching across national borders

Handbooks are assigned the task of presenting knowledge in a systematic manner for practical learning purposes. This is less immediate for spatial planning, a complex (and sometimes confusing) field of knowledge, also because of the different legal frameworks and cultural traditions in which it is practiced. Handbooks in planning are indeed used to refer the teaching to a specific national context, but this may lead to confusing the technical nature of planning with its institutional codification. The handbook recently published by the present authors in Italy builds on the assumption that planning education requires, first and foremost, that students understand its value as specific technical knowledge. From this assumption follows the distinction between ‘spatial governance’ and ‘spatial planning’, adopted in the handbook. The proposed contribution summarises the educational choices behind the handbook in five theses, which are discussed as a basis for teaching planning in an international perspective: 1) urban planning is a field of knowledge, teaching its technical aspects means teaching spatial planning; 2) to teach spatial planning we must explain why it is instrumental for the purposes of spatial governance; 3) the technique of spatial planning originated from recognisable matrices, the teaching of which lays the foundations for all subsequent learning; 4) also for teaching purposes, the technique of spatial planning can be traced back to zoning; 5) spatial governance is not a form of technical knowledge, but a political practice that may be taught insofar as it is necessary for understanding the effects of spatial planning

Sensorless finite-control set model predictive control for IPMSM drives

This paper investigates the feasibility of a sensorless field oriented control (FOC) combined with a finite control set model predictive current control (FCS-MPC) for an interior permanent magnet synchronous motor (IPMSM). The use of a FCS-MPC makes the implementation of most of the existing sensorless techniques difficult due to the lack of a modulator. The proposed sensorless algorithm exploits the saliency of the motor and the intrinsic higher current ripple of the FCS-MPC to extract position and speed information using a model-based approach. This method does not require the injection of additional voltage vectors or the periodic interruption of the control algorithm and consequently it has no impact on the performance of the current control. The proposed algorithm has been tested in simulation and validated on an experimental set-up, showing promising results

Rhinocerotidae (Mammalia, Perissodactyla) from the middle Pleistocene levels of Grotta Romanelli (Lecce, southern Italy)

The rhinoceros remains collected during the past century in the lower levels XII (= K) and XI (= I) of the famous Pleistocene locality of Grotta Romanelli (Lecce, southern Italy) are described and compared in detail for the first time. Some remains are referred to Stephanorhinus sp. and others are assigned here to the late early-middle Pleistocene European species Stephanorhinus hundsheimensis based on several morphological characters. Based on its olivine-bearing texture, the volcanoclastic ash sampled from some rhinoceros bones can be referred to the first phase of the Monte Vulture activity (around 630 ka). The results of the stable isotope analyses suggest that the climate in the lowest levels of Grotta Romanelli could have been more arid than it was at the time of the upper level IX, which is generally referred to the late Pleistocene. In addition, both recent day δ18Opptvalues and MAT are very similar to values calculated for levels X and XII, suggesting that the climate at those times may have been close to the Present one, whereas climate in level IX may have been somewhat cooler. The presence of Stephanorhinus hundsheimensis suggests a middle Pleistocene age for the lower levels of Grotta Romanelli, in agreement with the results obtained from the volcanoclastic material

A distributed model predictive control strategy for back-to-back converters

In recent years Model Predictive Control (MPC) has been successfully used for the control of power electronics converters with different topologies and for different applications. MPC offers many advantages over more traditional control techniques such as the ability to avoid cascaded control loops, easy inclusion of constraint and fast transient response. On the other hand, the controller computational burden increases exponentially with the system complexity and may result in an unfeasible realization on modern digital control boards. This paper proposes a novel Distributed Model Predictive Control, which is able to achieve the same performance of the classical Model Predictive Control whilst reducing the computational requirements of its implementation. The proposed control approach is tested on a AC/AC converter in a back-to-back configuration used for power flow management. Simulation results are provided and validated through experimental testing in several operating conditions

Model Predictive Control for shunt active filters with fixed switching frequency

This paper presents a modification to the classical Model Predictive Control algorithm, named Modulated Model Predictive Control, and its application to active power filters. The proposed control is able to retain all the advantages of a Finite Control Set Model Predictive Control whilst improving the generated waveforms harmonic spectrum. In fact a modulation algorithm, based on the cost function ratio for different output vectors, is inherently included in the MPC. The cost function-based modulator is introduced and its effectiveness on reducing the current ripple is demonstrated. The presented solution provides an effective and straightforward single loop controller, maintaining an excellent dynamic performance despite the modulated output and it is self-synchronizing with the grid. This promising method is applied to the control of a Shunt Active Filter for harmonic content reduction through a reactive power compensation methodology. Significant results obtained by experimental testing are reported and commented, showing that MPC is a viable control solution for active filtering systems

Governo del territorio e pianificazione spaziale

Per insediarsi e convivere stabilmente le società umane organizzano e controllano lo spazio. Devono cioè distribuire le attività e gli edifici che le accolgono, distinguere i luoghi destinati alle attività private da quelli destinati alle attività comuni, consentire gli spostamenti, regolamentare la costruzione di edifici e infrastrutture. Da sempre lo strumento usato per l’organizzazione e il controllo dello spazio è il piano. La pianificazione spaziale è dunque il sapere tecnico che elabora gli strumenti e le modalità di configurazione dello spazio: modelli insediativi, piani, parametri e regole d’uso del suolo, progetti. Il governo del territorio – espressione che dal 2001 ha sostituito il termine «urbanistica» nella Costituzione italiana – è il processo decisionale col quale il potere politico assegna i diritti d’uso e di trasformazione del suolo, servendosi della pianificazione spaziale. In un tempo d’incertezza e, per molti aspetti, di crisi della cultura della pianificazione spaziale, accademica e professionale, questo manuale mette in evidenza le ragioni e le funzioni sociali, economiche e istituzionali dei piani e dei sistemi di governo del territorio, e ne descrive criticamente caratteri e contenuti attraverso l’esame di casi italiani e stranieri, antichi e recenti