237 research outputs found
A data-driven prognostic approach based on statistical similarity: An application to industrial circuit breakers
No full textIn this paper, a data-driven prognostic algorithm for the estimation of the Remaining Useful Life (RUL) of a product is proposed. It is based on the acquisition and exploitation of run-to-failure data of homogeneous products, in the followings referred as fleet of products. The algorithm is able to detect the set of products (sub-fleet of products) showing highest degradation pattern similarity with the one under study and exploits the related monitoring data for a reliable prediction of the RUL. In particular, a novel methodology for the sub-fleet identification is presented and compared with other solution found in literature. The results obtained for a real application case as Medium and High Voltage Circuit Breaker, have shown a high prognostic power for the algorithm, which therefore represents a potential tool for an effective Predictive Maintenance (PdM) strategy
A performance model for medium voltage equipment
No full textThis paper presents a performance model for condition monitoring, diagnostics and prognostics of Medium Voltage (MV) breakers and switchgears. Scope of the performance model is to assess the current health condition, to predict the future health condition and, possibly, to provide indications about the cause of potential failures of MV equipment. The outcomes of the performance model are then meant to provide relevant information for any successful riskbased, condition-based and predictive maintenance strategy. The performance model presented in this paper is based on the concept of "competing" failure modes. It is modular and scalable in order to take into account different scenarios of data availability (from static product nameplate data to dynamic condition monitoring and test data) and MV equipment of different manufacturers. Finally, the performance model may be easily adapted to any kind of assets
An algorithm for data-driven prognostics based on statistical analysis of condition monitoring data on a fleet level
No full textThe availability of condition monitoring data for large sets of homogeneous products (in the following referred as a fleet) motivates the development of new data-driven prognostic algorithms. In this paper, an intuitive and an innovative data-driven algorithm to predict the health and, consequently, the Residual Useful Lifetime (RUL) of a product are proposed. The algorithm is based on the extraction and exploitation of knowledge at a fleet level. The fleet-specific usage and the degradation profile are extracted by statistically analyzing the condition monitoring data of all the products that's belongs to the fleet. The extracted knowledge, in terms of statistical distribution of health condition and sampling time, is then exploited to predict the health and RUL of a product in the fleet. The algorithm described in this paper is able to predict the RUL of a product with a good credibility even for observation window lengths that are smaller compared to the lifetime of the product
VLC Physical Layer Security through RIS-aided Jamming Receiver for 6G Wireless Networks
No full textVisible Light Communication (VLC) is one the most promising enabling
technology for future 6G networks to overcome Radio-Frequency (RF)-based
communication limitations thanks to a broader bandwidth, higher data rate, and
greater efficiency. However, from the security perspective, VLCs suffer from
all known wireless communication security threats (e.g., eavesdropping and
integrity attacks). For this reason, security researchers are proposing
innovative Physical Layer Security (PLS) solutions to protect such
communication. Among the different solutions, the novel Reflective Intelligent
Surface (RIS) technology coupled with VLCs has been successfully demonstrated
in recent work to improve the VLC communication capacity. However, to date, the
literature still lacks analysis and solutions to show the PLS capability of
RIS-based VLC communication. In this paper, we combine watermarking and jamming
primitives through the Watermark Blind Physical Layer Security (WBPLSec)
algorithm to secure VLC communication at the physical layer. Our solution
leverages RIS technology to improve the security properties of the
communication. By using an optimization framework, we can calculate RIS phases
to maximize the WBPLSec jamming interference schema over a predefined area in
the room. In particular, compared to a scenario without RIS, our solution
improves the performance in terms of secrecy capacity without any assumption
about the adversary's location. We validate through numerical evaluations the
positive impact of RIS-aided solution to increase the secrecy capacity of the
legitimate jamming receiver in a VLC indoor scenario. Our results show that the
introduction of RIS technology extends the area where secure communication
occurs and that by increasing the number of RIS elements the outage probability
decreases
Telework as a driver of inequalities in the labour market
No full textThe contribution focuses on telework, arguing that its spread is likely to exacerbate the already existing inequalities in the labour market. After outlining the reasons for the so-called teleworkability divide, the Author shows that thecleavage between those who can and those who cannot work remotely is not neutral, but rather a factor that accelerates and sharpen disparities among groups of workers, favouring onlysome of them. Attention will also be paid to the issue of discrimination in teleworking access policies and that of its so-called segregating effect. Finally, some possibleremedies to the detrimental consequences of the teleworkability divide are proposed
A comparative study on data-driven prognostic approaches using fleet knowledge
No full textRecently, Prognostics and Heath Management techniques have been deeply investigated with the aim to reduce life-cycle cost of products and systems. The increasing availability of condition monitoring data in substantial quantities for multitudes of homogeneous products and the need for generic algorithms that are applicable to complex systems motivates the development of new data-driven prognostic approaches. In this paper, two data-driven algorithms, one based on a statistical approach and another based on Neural Network, are discussed and tested for an application case. The analysis of the results has shown that both the considered approaches are characterized by reliable prediction performances on Remaining Useful Life calculation, thus resulting as potential tools for the application of a Condition-Based Maintenance strategy
L’esclusione del socio lavoratore di cooperativa per motivi discriminatori: quali tutele alla luce del diritto eurounitario?
No full textL’Autore intende dimostrare come, alla luce della giurisprudenza della Corte di giustizia dell’Unione europea in tema di sanzioni per la violazione di diritti attribuiti ai singoli dall’ordinamento eurounitario, le tutele riconosciute dal diritto nazionale al socio lavoratore di cooperativa che sia stato estromesso dalla compagine societaria per motivi inerenti ad uno dei cosiddetti fattori protetti individuati dalla normativa antidiscriminatoria di matrice europea e che, pur avendo impugnato il provvedimento di recesso intimatogli, abbia mancato di impugnare in tempo utile la delibera di esclusione non siano conformi agli standards prescritti dal diritto comunitario, dovendosi garantire al lavoratore – nel caso di licenziamento discriminatorio – la reintegrazione nel posto di lavoro o, in alternativa, un risarcimento adeguato e commisurato al danno patito.The Author intends to demonstrate how, in light of the case law of the Court of Justice of the European Union on sanctions for the violation of rights attributed to individuals by the European Union legal system, the protections granted by national law to the worker member of a cooperative who has been expelled from the company for reasons inherent in one of the so-called protected factors identified by the European anti-discrimination legislation and who, despite having challenged the decision to dismiss him/her, has failed to appeal in due time against the decision to exclude him/her, do not comply with the standards laid down by Community law, since the employee – in the event of discriminatory dismissal – must be guaranteed reinstatement in his/her place of employment or, alternatively, adequate compensation commensurate with the damage suffered
Performance Assessment Strategies: A computational framework for conceptual design of large roofs
No full textUsing engineering performance evaluations to explore design alternatives during the conceptual phase of architectural design helps to understand the relationships between form and performance; and is crucial for developing well-performing final designs. Computer aided conceptual design has the potential to aid the design team in discovering and highlighting these relationships; especially by means of procedural and parametric geometry to support the generation of geometric design, and building performance simulation tools to support performance assessments. However, current tools and methods for computer aided conceptual design in architecture do not explicitly reveal nor allow for backtracking the relationships between performance and geometry of the design. They currently support post-engineering, rather than the early design decisions and the design exploration process.
Focusing on large roofs, this research aims at developing a computational design approach to support designers in performance driven explorations. The approach is meant to facilitate the multidisciplinary integration and the learning process of the designer; and not to constrain the process in precompiled procedures or in hard engineering formulations, nor to automatize it by delegating the design creativity to computational procedures. PAS (Performance Assessment Strategies) as a method is the main output of the research. It consists of a framework including guidelines and an extensible library of procedures for parametric modelling. It is structured on three parts.
Pre-PAS provides guidelines for a design strategy-definition, toward the parameterization process. Model-PAS provides guidelines, procedures and scripts for building the parametric models. Explore-PAS supports the solutions-assessment based on numeric evaluations and performance simulations, until the identification of a suitable design solution. PAS has been developed based on action research. Several case studies have focused on each step of PAS and on their interrelationships.
The relations between the knowledge available in pre-PAS and the challenges of the solution space exploration in explore-PAS have been highlighted. In order to facilitate the explore-PAS phase in case of large solution spaces, the support of genetic algorithms has been investigated and the exiting method ParaGen has been further implemented. Final case studies have focused on the potentials of ParaGen to identify well performing solutions; to extract knowledge during explore-PAS; and to allow interventions of the designer as an alternative to generations driven solely by coded criteria.
Both the use of PAS and its recommended future developments are addressed in the thesis
Preface
No full textCAAD Futures is a biennial international conference on Computer-Aided Architectural Design under the umbrella of the CAAD Futures Foundation, and it is active world-wide in advancing and documenting related research. On 5–7 July 2023, the 20th CAAD Futures conference was hosted at Delft University of Technology. The CAAD Futures Foundation was established in 1985, holding the first conference on 18–19 September of that year at the very same University. The return of the conference to Delft for its 20thedition offered a chance to reflect on the past, present and future role of Computation in Architecture and the Built Environment. With reference to the theme of “INTERCONNECTIONS: Co-computing beyond boundaries”, CAAD Futures 2023 reflected on the role of computation to interconnect in and for Architectural Design.Digital TechnologiesArchitectural Technolog
PULSE: Integrated Parametric Modeling for a Shading System: From Daylight Optimization to Additive Manufacturing
No full textThis paper presents a parametric approach to an integrated and performance-oriented design, from the conceptual design phase towards materialization. The novelty occurs in the use of parametric models as a way of integrating multidisciplinary design constraints, from daylight optimization to the additive manufacturing process. The work focuses on the case of a customized sun-shading system that tailors daylighting effects for a fully glazed façade of the alleged PULSE building.The overall workflow includes preliminary analysis on simplified models and an initial parametric model to run computational optimization loops. The output consists of individually unique sun-shading panels, optimized for varying daylighting requirements based on programmatic distribution and specified viewing areas. The resulting geometric complexity was resolved through subsequent detailed parametric models; implementing the structural design requirements and integrating the constraints dictated by the additive manufacturing process, including the necessity to minimize material and 3D-printing time. This paper focuses on a particular part of the overall workflow, describing the support provided by parametric modelling to control geometric complexity and multi-disciplinary requirements.Design Informatic
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