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  <front>
    <journal-meta>
      <journal-title-group>
        <journal-title>Ital-IA</journal-title>
      </journal-title-group>
      <issn pub-type="ppub">1613-0073</issn>
    </journal-meta>
    <article-meta>
      <title-group>
        <article-title>AI in Industry: Activities of the CINI-AIIS Lab at University of Naples Federico II</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Alessandro Del Prete</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Sofia</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Dutto</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Antonino Ferraro</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Antonio Galli</string-name>
          <email>antonio.galli@unina.it</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Vincenzo Moscato</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Gabriele Piantadosi</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Carlo Sansone</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Giancarlo Sperlì</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="editor">
          <string-name>Predictive Maintenance, Energy Forecasting, Anomaly Detection, Remaining Useful Life.</string-name>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>ENEA, Centro Ricerche Portici</institution>
          ,
          <addr-line>80055 Portici (NA)</addr-line>
          ,
          <country country="IT">Italy</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>University of Naples Federico II</institution>
          ,
          <addr-line>via Claudio 21, Naples, 80125</addr-line>
          ,
          <country country="IT">Italy</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2024</year>
      </pub-date>
      <volume>4</volume>
      <fpage>29</fpage>
      <lpage>30</lpage>
      <abstract>
        <p>Artificial intelligence (AI) is reshaping the manufacturing landscape, ofering opportunities for eficiency improvements and innovation. Through Machine Learning (ML) and Deep Learning (DL), AI enables predictive maintenance, anomaly detection, and image analysis in industrial settings. ML algorithms empower systems to learn from data, facilitating predictive maintenance by predicting optimal equipment servicing schedules based on operational conditions. DL techniques, including Convolutional Neural Networks (CNNs), are revolutionizing industrial image analysis by extracting intricate features for quality control and defect detection. Moreover, the integration of DL with natural language processing (NLP) streamlines tasks like document analysis and inventory management. At the University of Naples Federico II's CINI-AIIS Lab, cutting-edge AI projects are underway, showcasing the transformative potential of AI in the industry sector.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>CEUR
ceur-ws.org</p>
    </sec>
    <sec id="sec-2">
      <title>1. Introduction</title>
      <p>Artificial intelligence (AI) is transforming various
industries, including the manufacturing sector, by emulating
human intelligence to tackle complex challenges. In the
industrial domain, AI holds significant promise,
enhancing operational eficiency, optimizing processes, and
drivthe CINI-AIIS Lab, highlighting their innovative
contributions.
2. Prediction and Forecasting for
railway rolling stock equipment
ing innovation. AI-powered systems can analyze exten- The manufacturing industry is currently undergoing the
sive datasets to detect anomalies, predict equipment
failso-called Industry 4.0 revolution, characterized by the
exures, and improve overall productivity. Machine Learn- tensive integration of physical and digital realms within
ing (ML), a subset of AI, enables systems to learn from
data and make informed decisions, such as predicting
production settings. Key technologies driving this
revolution include the Industrial Internet of Things, Big Data,
optimal maintenance schedules based on equipment con- Artificial Intelligence, and advanced telecommunications
ditions and operational context.</p>
      <p>like 4G and 5G, which profoundly influence the
trans</p>
      <p>Deep Learning (DL), another ML subset, leverages Ar- port sector. These innovations enable the gathering of
tificial Neural Networks (ANNs) to process complex data
vast data from diverse onboard devices and equipment
patterns and make accurate predictions. DL, particu- installed on train vehicles and along railway tracks.
larly through Convolutional Neural Networks (CNNs), is
revolutionizing industrial image analysis by extracting
meaningful features from images for quality control and</p>
      <p>This wealth of data, acquired through smart sensors
and relayed to diagnostic systems either onboard or in
control rooms, holds immense potential. By
employdefect detection. Additionally, DL, combined with Nat- ing appropriate techniques, it can unveil patterns of
ural Language Processing (NLP), is streamlining tasks
like document analysis and inventory management. The
degradation in components and anticipate failures in
a timely manner, facilitating optimal maintenance
deversatility of AI underscores its pivotal role in the manu- cisions. Traditionally, players in the railway transport
facturing industry, driving eficiency gains and fostering
innovation.</p>
      <p>In this paper, we showcase AI projects in the industrial
sector from the University of Naples Federico II node of
sector have relied on planned maintenance, often
resulting in unnecessary actions and inflated operating costs.</p>
      <sec id="sec-2-1">
        <title>However, the evolution towards Condition-Based Main</title>
        <p>tenance (CBM) ofers a proactive alternative. CBM, an
extension of planned maintenance, assesses equipment
conditions through direct measurements, enabling timely
repairs or replacements when specific conditions are met.</p>
      </sec>
      <sec id="sec-2-2">
        <title>Predictive Maintenance takes CBM a step further by</title>
        <p>© 2024 Copyright for this paper by its authors. Use permitted under Creative Commons License leveraging monitoring data and efective predictive
techAttribution 4.0 International (CC BY 4.0).
niques to anticipate fault occurrences. This approach Mann-Kendall) and correlation, to uncover relationships
enables companies to schedule maintenance operations between dataset features and failure patterns.
Subseprecisely when needed, leading to cost reductions, de- quently, LSTM networks are utilized to both predict and
creased mean time to failures, and overall profit enhance- forecast failures, ofering valuable insights to
maintement. The key advantage lies in conducting maintenance nance personnel responsible for rolling stock equipment.
preemptively, averting prolonged downtime without re- Our methodology achieves an accuracy exceeding 99%
sorting to premature interventions, thus minimizing the for both prediction and forecasting tasks, surpassing
exunavailability of rolling stock and infrastructure equip- isting ML models and techniques in the predictive
mainment. tenance literature. Moreover, the error rates for
pre</p>
        <p>Machine Learning (ML) algorithms emerge as power- diction and forecasting tasks are notably low, with a
ful tools in maintenance across diverse domains, owing false alarm rate of approximately 0.4% and a mean
absoto their support for predictive techniques. ML techniques lute error on the order of 10−4. These results are highly
have been applied extensively, from predicting light bulb promising compared to previous studies. Additionally,
failures to early detection of machine failures, rotating the methodology is validated against real-world systems
machinery failure prediction, and estimating the Remain- by our industry partner, confirming the soundness of our
ing Useful Life (RUL) of various assets like hard disks assumptions and approaches.
and wind turbines. In the railway domain, ML is
gaining prominence in enhancing operations and reliability.</p>
        <p>However, the eficacy of ML algorithms hinges on select- 3. Forecast and Anomaly Detection
ing the appropriate technique, especially considering the in Photovoltaic System
gradual deterioration or sudden failure characteristic of
rail systems. Thus, ML approaches for predictive main- In the context of the global energy landscape, the
Internatenance must account for such data dynamics to ensure tional Energy Agency (IEA) highlights the pivotal role of
accurate failure prediction and forecasting. photovoltaic (PV) energy in driving the ongoing energy</p>
        <p>
          We introduced a deep learning-based methodology transition, as indicated in the World Energy Outlook 2023
which enables the prediction and forecasting of failures, [
          <xref ref-type="bibr" rid="ref1">1</xref>
          ]. Despite the adoption of the Stated Policies Scenario
allowing for proactive maintenance interventions to be (STEPS), it is observed that the utilization rate of solar
planned before they occur, thereby optimizing both the energy markets lags behind the expanding production
cost and duration of maintenance activities. Utilizing capacity of PV technologies (Figure 2).
Long Short-Term Memory (LSTM) networks, an exten- Recognizing the imperative for a paradigm shift within
sion of recurrent neural networks (RNN), the methodol- the PV market, encompassing both domestic and
indusogy is adept at learning long-term dependencies in data trial installations, there is a pressing need for active
inthat change gradually over time. An overview of the volvement from network and infrastructure
stakeholdmethodology is provided in Figure 1. ers, energy producers, and consumers [
          <xref ref-type="bibr" rid="ref2">2</xref>
          ]. These entities,
        </p>
        <p>The proposed approach analyzes data collected from frequently coalescing into energy communities, aim to
numerous sensors distributed across the various subsys- foster sustainable energy exchange paradigms,
necessitems of a railway vehicle, with a particular focus on the tating the development of novel tools. These tools must
critical train traction converter cooling subsystem. Oper- render photovoltaic production economically viable for
ational data from a train fleet spanning several months energy trading while ensuring environmental
sustainabilis examined. The framework employs classic statistical ity through reductions in energy storage requirements
data analysis techniques, such as trend estimation (e.g., and efective planning for grid load and
dispersion/utiarchitecture.</p>
        <p>This result allowed us to test an anomaly detection
procedure by comparing the predicted result with the power
produced by each individual inverter. When
considering a single plant and computing the prediction error,
it is possible to put into practice a simple but efective
anomaly detection technique as shown in Figure 4.</p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>4. Predictive Maintenance in IoT scenarios</title>
      <p>
        The proposed approach, as presented in Figure 3,
entails the integration of a selected provider from among
global numerical and commercial models. This choice
is informed by preliminary results. The integration in- We are currently immersed in the Industry 4.0 era,
volves coupling this provider with a mathematical and marked by the continual automation of traditional
manuphysical model of irradiance [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ], with the objective of facturing and industrial processes through modern smart
efectively propagating irradiance contributions through technologies like Internet of Things (IoT) and Artificial
suitable machine learning models. Long short-term mem- Intelligence (AI) ([
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]). This evolution demands an
increasory (LSTM) and Transformer Neural Networks (NN) mod- ing integration between physical and digital systems in
els will be considered, with comparisons drawn against production environments, enabling the collection of vast
classical machine learning techniques. To optimize the data from various smart equipment and sensors.
model’s performance, an appropriate weighted combina- Smart sensors, devices generating data on physical
pation of losses will be employed during the training pro- rameters (e.g., temperature, humidity, or vibration speed),
cess. The training is conducted using real data sourced ofer functionalities ranging from self-monitoring to
manfrom managed photovoltaic systems situated at five dis- aging complex processes ([
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]).
tinct Italian sites. By leveraging this combination of Analyzing such data yields insights into machinery
numerical, commercial, and machine learning models, health and production levels, driving strategic
decisionthe proposal aims to enhance the accuracy and predic- making for benefits like reduced maintenance costs,
tive capability of the system, paving the way for a more fewer machine faults, optimized inventory, and increased
efective utilization of solar energy resources. production. Maintenance procedures are a key focus,
      </p>
      <p>Preliminary results shows up to 0.536 ± 0.015% mean given their significant impact on industrial production
absolute percentage error (MAPE) on power yield fore- and service availability. Industries are investing heavily
casting (99% CI validated) using a seq2seq Transformer
in equipping themselves with the tools for data-driven connected network module.
maintenance strategies. The experimental results demonstrate how the
pro</p>
      <p>
        In the literature, two main approaches support main- posed approach efectively meets the demands of
modtenance: model-driven and data-driven methods, with ern embedded AI applications, particularly benefiting
hybrid-driven approaches gaining traction. While model- smart manufacturing systems where reliability, low
ladriven techniques rely on expert theoretical understand- tency, privacy, and low power are critical. These findings
ing, data-driven techniques leverage the vast information have significant management implications for optimizing
available to detect machinery anomalies ([
        <xref ref-type="bibr" rid="ref6 ref7">6, 7</xref>
        ]). Hybrid- production line operations.
driven solutions merge model and data fusion ([
        <xref ref-type="bibr" rid="ref8 ref9">8, 9</xref>
        ]). Future research could explore further applications of
Maintenance management approaches, as categorized the attention mechanism in predictive maintenance.
Adby ([
        <xref ref-type="bibr" rid="ref10">10</xref>
        ]), include Run-to-Failure (R2F), Preventive Main- ditionally, investigating what aspects the model
prioritenance (PvM), and Predictive Maintenance (PdM). Our tizes (i.e., receives more attention) could be insightful,
focus is on PdM, which relies on data-driven analysis potentially leveraging eXplainable Artificial Intelligence
to predict machinery failures, optimizing maintenance (XAI) tools to provide explanations.
procedures and increasing machine longevity ([
        <xref ref-type="bibr" rid="ref11 ref12">11, 12</xref>
        ]).
      </p>
      <p>
        In many domains with complex data, machine
learning and deep learning techniques stand out for predictive 5. Forecasting Remaining Useful
maintenance ([
        <xref ref-type="bibr" rid="ref13 ref14 ref15">13, 14, 15</xref>
        ]). These approaches use histori- Life in Aerospace Maintenance
cal datasets to train models for predicting failures, such
as Remaining Useful Life (RUL) estimation. The aerospace industry is known for its strict safety
stan
      </p>
      <p>
        However, deploying deep learning in real-world IoT dards, regulatory requirements, and the importance of
efscenarios faces challenges due to computational limi- ficient maintenance to keep operations running smoothly.
tations. Edge/fog computing solutions are favored but While traditional maintenance methods like preventive
influenced by network connectivity ([
        <xref ref-type="bibr" rid="ref16">16</xref>
        ]). Embedded AI and reactive maintenance have their drawbacks in terms
techniques are increasingly proposed for eficient, cost- of cost and accurately predicting failures, predictive
mainefective data-driven analysis on industrial equipment tenance driven by AI and data analytics is a more
proachardware ([
        <xref ref-type="bibr" rid="ref17">17</xref>
        ]). tive and cost-efective solution that can help overcome
      </p>
      <p>This proposal presents a deep learning approach for these challenges.
predictive maintenance, leveraging a multi-head attention PdM uses data from sensors, operation logs, and
mainmechanism for high RUL estimation accuracy and low tenance records to monitor equipment health and predict
memory requirements, suitable for hardware implemen- failures. By forecasting the remaining useful life of key
tation. Experimental results demonstrate its efectiveness components, it prevents unplanned downtime, cuts
mainand eficiency, making it a promising solution for real- tenance costs, and improves safety.
world PdM scenarios. The focus is on using advanced algorithms such as</p>
      <p>Figure 5 presents a high-level overview of the proposed LSTM networks and Transformer models to improve
model architecture for the described PdM task, along maintenance schedules in the aerospace industry using
with the data analysis pipeline necessary for generating the C-MAPSS dataset, which contains sensor readings
estimated RUL values. and remaining useful life (RUL) values for turbofan jet
en</p>
      <p>The input comprises historical data from sensors pro- gines under diferent operating conditions. These types
viding crucial information about the monitored machin- of deep learning models have shown great success in
ery’s conditions, which includes a temporal component understanding intricate time-based patterns and distant
crucial for detecting degradation trends. connections in data sequences.</p>
      <p>Once the input data is processed, it’s fed into the model The C-MAPSS dataset is highly valued in the research
capable of capturing temporal dependencies between fea- community and widely used. Many researchers consider
tures. By setting an appropriate time window, the input it a valuable resource for studying intelligent
maintedata fed into the model forms a matrix of size (  ,   ), nance and machine health prognosis as shown in the
where   represents the length of the input time window ifgure 6.
and   denotes the number of considered features. The The LSTM network, with its gating mechanisms
(formodel output is a real number representing the remain- get, input, and output gates) and capability to selectively
ing useful life of the machinery. The main components of retain or discard information over time, proved adept
the proposed architecture include: positional encoding at modeling long-term dependencies intrinsic to
timeblock, accounting for the relative or absolute position of series data. Conversely, the Transformer model,
origthe time-steps in the input sequence; the attention mod- inally designed for natural language processing tasks,
ule, comprising two sub-layers with residual connections employed a self-attention mechanism and position-wise
between them: the multi-head attention block and fully
feed-forward networks to capture distant relationships
within the input sequences efectively.</p>
      <p>Through rigorous testing and analysis using various
metrics like mean absolute error, loss function and  2
values, our findings show that LSTM networks outperform
Transformers in accurately forecasting RUL 1.</p>
      <p>The results analysis indicates that while the
Transformer model shows good performance in predicting
engine performance, it falls short compared to the LSTM
model, likely due to dataset limitations rather than
architectural constraints. The Transformer’s self-attention
mechanism and lack of an explicit recurrent structure
like LSTMs may require more diverse data to accurately
capture sequential patterns, especially in complex
timeseries tasks. Understanding and predicting engine
performance over time relies heavily on modeling long-term
temporal dependencies, which can be challenging with a
limited number of representative examples in the dataset.</p>
      <p>The Transformer’s ability to efectively handle such
temporal contexts is influenced by the quality and
comprehensiveness of the training data it receives. Further
research could explore new model architectures, ensemble
techniques and optimization strategies to improve model
performance and address specific challenges associated
with time series data.</p>
    </sec>
    <sec id="sec-4">
      <title>Acknowledgments</title>
      <sec id="sec-4-1">
        <title>This work was supported in part by the Piano Nazionale Ripresa Resilienza (PNRR) Ministero dell’Università e della Ricerca (MUR) Project under Grant PE0000013-FAIR</title>
      </sec>
    </sec>
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