Higher Institute on Territorial Systems for Innovation
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From local averaging to emergent global behaviors: The fundamental role of network interconnections
No full textAttitude recovery from feature tracking for estimating angular rate of non-cooperative spacecraft
No full textThis paper presents a fault-tolerant method for estimating the angular rate of uncontrolled bodies in space, such as failed spacecrafts. The bodies are assumed to be free of any sensors; however, a planned mission is assumed to track several features of the object by means of stereo-vision sensors. Tracking bodies in the space environment using these sensors is not, in general, an easy task: obtainable information regarding the attitude of the body is often corrupted or partial. The developed method exploits this partial information to completely recover the attitude of the body using a basis pursuit approach. An unscented Kalman filter can then be used to estimate the angular rate of the body
Design and optimization of Artificial Neural Networks for the modelling of superconducting magnets operation in tokamak fusion reactors
No full textIn superconducting tokamaks, the cryoplant provides the helium needed to cool different clients, among which by far the most important one is the superconducting magnet system. The evaluation of the transient heat load from the magnets to the cryoplant is fundamental for the design of the latter and the assessment of suitable strategies to smooth the heat load pulses, induced by the intrinsically pulsed plasma scenarios characteristic of today's tokamaks, is crucial for both suitable sizing and stable operation of the cryoplant. For that evaluation, accurate but expensive system-level models, as implemented in e.g. the validated state-of-the-art 4C code, were developed in the past, including both the magnets and the respective external cryogenic cooling circuits. Here we show how these models can be successfully substituted with cheaper ones, where the magnets are described by suitably trained Artificial Neural Networks (ANNs) for the evaluation of the heat load to the cryoplant. First, two simplified thermal-hydraulic models for an ITER Toroidal Field (TF) magnet and for the ITER Central Solenoid (CS) are developed, based on ANNs, and a detailed analysis of the chosen networks' topology and parameters is presented and discussed. The ANNs are then inserted into the 4C model of the ITER TF and CS cooling circuits, which also includes active controls to achieve a smoothing of the variation of the heat load to the cryoplant. The training of the ANNs is achieved using the results of full 4C simulations (including detailed models of the magnets) for conventional sigmoid-like waveforms of the drivers and the predictive capabilities of the ANN-based models in the case of actual ITER operating scenarios are demonstrated by comparison with the results of full 4C runs, both with and without active smoothing, in terms of both accuracy and computational time. Exploiting the low computational effort requested by the ANN-based models, a demonstrative optimization study has been finally carried out, with the aim of choosing among different smoothing strategies for the standard ITER plasma operatio
Sol-Gel and Layer by Layer Methods for Conferring Multifunctional Features to Cellulosic Fabrics: An Overview
No full textThis chapter reviews the recent advances referring to the use of sol-gel processes and layer by layer (LbL) treatments for conferring multifunctional features to cellulosic fabrics (namely cotton and its blends with polyester). In fact, these two approaches, which have been successfully applied to both natural and synthetic fabrics, can be very effective in providing multifunctional features to the treated fabrics, through the formation of a ceramic - or polymer /ceramic-based coating (sol-gel ), or by depositing a nanostructured organic, inorganic or hybrid assembly (LbL) on the underlying textile. Sol-gel is based on a bottom-up strategy, starting from different precursors, from which it is possible to tailor the final surface properties of the treated substrates. Conversely, layer by layer exploits a top-down method, suitable for the design of very thin and, at the same time, performing coatings. Among the different possible multifunctional properties the two approaches can provide to cellulosic substrates, fire retardancy, hydrophobicity, wear resistance and anti-bacterial activity seem to fulfill the up-to-date needs coming from either the academic or industrial world. This work thoroughly reviews the development and the recent advances achieved by the two strategies, showing their potentialities and current limitations
Using inertial measurement units originally developed for biomechanics for modal testing of civil engineering structures
No full textThis paper explores the use of wireless Inertial Measurement Units (IMU) originally developed for bio-mechanical research applications for modal testing of civil engineering infrastructure. Due to their biomechanics origin, these devices combine a triaxial accelerometer with gyroscopes and magnetometers for orientation, as well as on board data logging capability and wireless communication for optional data streaming and to coordinate synchronisation with other IMUs in a network. The motivation for application to civil structures is that their capabilities and simple operating procedures make them suitable for modal testing of many types of civil infrastructure of limited dimension including footbridges and floors while also enabling recovering of dynamic forces generated and applied to structures by moving humans. To explore their capabilities in civil applications, the IMUs are evaluated through modal tests on three different structures with increasing challenge of spatial and environmental complexity. These are, a full-scale floor mock-up in a laboratory, a short span road bridge and a seven story office tower. For each case, the results from the IMUs are compared with those from a conventional wired system to identify the limitations. The main conclusion is that the relatively high noise floor and limited communication range will not be a serious limitation in the great majority of typical civil modal test applications where convenient operation is a significant advantage over conventional wired system
Governo del territorio e pianificazione spaziale
No full textPer 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
Formally sound implementations of security protocols with JavaSPI
No full textDesigning and coding security protocols is an error prone task. Several flaws are found in protocol implementations and specifications every year. Formal methods can alleviate this problem by backing implementations with rigorous proofs about their behavior. However, formally-based development typically requires domain specific knowledge available only to few experts and the development of abstract formal models that are far from real implementations. This paper presents a Java-based protocol design and implementation framework, where the user can write a security protocol symbolic model in Java, using a well defined subset of the language that corresponds to applied π-calculus. This Java model can be symbolically executed in the Java debugger, formally verified with ProVerif, and further refined to an interoperable Java implementation of the protocol. Soundness theorems are provided to prove that, under some reasonable assumptions, a simulation relation relates the Java refined implementation to the symbolic model verified by ProVerif, so that, for the usual security properties, a property verified by ProVerif on the symbolic model is preserved in the Java refined implementation. The applicability of the framework is evaluated by developing an extensive case study on the popular SSL protocol
Systems Engineering and Its Application to Industrial Product Development
Get PDFPREFACE : Mastering the complexity of innovative systems currently looks a challenging goal of design and product development as well as embedding a suitable degree of smartness in devices, machines and equipment to make them able of adapting their operation to variable conditions or effects of a harsh environment. This goal is achieved through a continuous monitoring of the system in service, an effec-tive control of its behavior and a wide connectivity towards many other systems. Only an effective system design and manufacture, able to cover all the required actions, can assure this kind of assessment overall the life cycle since a very ear-ly concept of the product to a full disposal and service. Complexity makes hard managing the product development, because of the number of functions, subsystems, components and related interfaces usually in-volved, like in motor vehicles, robots, railways systems, aircrafts and spacecrafts as well as in large industrial manufacturing systems or very innovative microsys-tems and bioinspired devices. A crucial issue in this activity is performing a bright and complete elicitation of requirements, which need to be fully and suit-ably allocated to the system components, through a clear traceability, especially in systems produced as a result of material processing and assembling of parts. Moreover, the product must fit the requirements associated to some customer needs, innovation targets, and technical standards and be compatible with the manufacturer's capabilities. As it looks clear from the current state-of-art, since several years the Systems Engineering assures a suitable answer to the needs above mentioned. It provides a methodology to drive the product lifecycle assessment that is implemented through a well defined process, being based on some specific and graphical lan-guages and even formalized in several tools enabling the required analyses, tak-ing advantage of the capabilities of some dedicated commercial software. Those contents lead to create a platform, consisting of a sort of tools chain, which might be used and shared among different industrial and professional partners to digitalize both the information and even the whole industrial product develop-ment, as far as the current strategy referred to as "Industry 4.0 / The Factory of the Future" brightly suggests and supports. The so-called Model Based Systems Engineering (MBSE) is then successfully proposing an effective and modern al-ternative to the document-based approach, using data models as a main element of the design process. Some technical standards already drive the user in imple-menting the Systems Engineering, thus leading to develop a systematic approach the design aimed at satisfying the customer needs. Suitable capabilities in the manufactured system are assured by the so-called architectural frameworks, which support the system development and integration. The Model Based Systems Engineering allows proceeding with a modeling activity which investigates requirements, behavior and architecture through a combined operational, functional and logical analysis, being linked and interop-erated with a mathematical and physical modeling, which is typically more known and widely used within the industrial engineering. A full integration of all the activities of the Product Lifecycle Management (PLM) is currently going on, to include the system architecture definition and its Application Lifecycle Man-agement (ALM) as well as the Product Data Management (PDM), i.e. the design activity together with the tasks of production, testing, homologation and service. A recognized standard certification to qualify the Systems Engineer is even available as the International Council on Systems Engineering (INCOSE) pro-vides. The scenario above described is strongly integrated with the increasing devel-opment of both the network and the cyber-physical systems, for a fully distribut-ed connectivity, to be exploited in advanced smart systems and devices as well as in intelligent manufacturing, according to the most recent strategies of innova-tion as the "Industry 4.0" initiative and the "Lean manufacturing" idea. Simulta-neously, the system smartness and connectivity together increase the demand of data transmission and elaboration, thus linking this topic to the technology of big data management, whilst they benefit of the progress in information technology, through a secure cloud based on the network. The context just described motivates the fast diffusion of the Model Based Systems Engineering as a tool for innovating all the production processes. The increasing demand of specialized software and of educational activities as well as the number of workshops and conferences focused on this topic confirm this trend. However, it might be remarked that several contributions to the literature about the Systems Engineering widely grew up during the last years, thus making the Reader sometimes confused, especially when approaching this topic at first. The Systems Engineering topics are so many that it looks rather difficult mas-tering its skills, without a preliminary classification of contents. Technical do-mains involved are mainly those of engineering and computer science, although many other ones play the role of a daily user of this methodology. According to the most recent development of the Systems Engineering, whose typical applica-tion fields were the software and electronic systems even for space missions, the current focus consists of several industrial systems, being gradually innovated by introducing the tailored solutions of mechatronics. It is worthy noticing that a significant advancement was introduced between the very early implementation of the Systems Engineering and its recent evolution, since several new applica-tions are focused on the production of systems, which need to be manufactured through a material processing. Usually, they exhibit some attributes related both to their physical nature and to the functions performed, thus requiring to model both their functional and physical behaviors together. This need is changing the scenario of the typical applications of the Systems Engineering as software de-sign. This handbook expressively avoids to cover all the typical contents of the spe-cialized literature of the Model Based Systems Engineering, whilst is aimed at making easier a first approach to this topic and sharing a preliminary experience performed by the authors within some industrial domains, by proceeding in the modeling activity in a real industrial environment. The main goal is drawing a sort of simple and hopefully clear roadmap in modeling and developing the in-dustrial and material systems and in implementing the Systems Engineering, par-ticularly in the design activity. Therefore, the target audience of this handbook includes professional engineers, scientists and students dealing with the Applica-tion Lifecycle Management and the system architecture assessment, more than the Product Data Management or the whole Product Lifecycle Management. The approach followed is that of introducing some examples of implementa-tion of the Systems Engineering, by proceeding step by step from the screening of needs and the elicitation of requirements till a synthesis of the system design. Each action will be referred to the literature, related to the implementation of the Systems Modeling Language or SysML and to the use of some tools available on market, thus highlighting benefits, drawbacks and current limitations of some dedicated software or even of some proposed methodologies. Several comments will be provided to describe the troubles shared among some users of the Sys-tems Engineering as they were detected in daily practice by the authors. They wish that this handbook could briefly and gradually provide the Reader with a preliminary guideline to approach professionally the Model Based Systems En-gineering, by understanding its main contents and applying it to the industrial environment. As a desired result, this work might be considered as an integration of some textbooks of Machine Design, and it is aimed at completing the education within Engineering Design or at simply providing a friendly introduction to the Systems Engineerin
An integrated mathematical model for the optimization of hybrid product-process layouts
No full textThe layout of a manufacturing process plays a significant role to maintain a profitable production and make competitive a company. Product-oriented layouts aim to minimize the distance travelled by the manufactured units; the process-oriented approach attempts to maximize the saturation of the facilities. However, in many cases a hybrid approach may be necessary to achieve a compromise between the two objectives. This paper aims to present a mathematical model capable to define a hybrid product-process layout by autonomously: (i) defining the process cells and, for each of them, evaluating the number of machines necessary for stability; (ii) identifying the position of the machines within each cell; (iii) determining the best position for the cells in a given shop-floor area; (iv) evaluating a set of KPIs for the obtained layout proposal. The numerical implementation of the model led to obtain a layout proposal within 10 seconds for a process made of 30 distinct operations. The approach is validated through case-studies taken from the automotive industry; the obtained results show that the model is an effective tool to support the activities of designers of manufacturing processes