## 3 State-of-the-Art Techniques for Predictive Maintenance
As a result, industries such as electrical equipment, machinery, electronic and optical equipment, and fabricated metal products are popular areas for AI and maintenance. On the other hand, computers and communication equipment, industrial machinery and equipment, and buildings and other structures categories have received more limited attention. These results are essential guidance for directing future research and development efforts. On the other hand, manufacturing industries, including automotive, aircraft, semiconductor, machine tools, gearbox, pharmaceutical, electronics, steel, robotics, industrial robotics, air conditioning, and industrial robots, are the industry sectors receiving the most attention in AI and maintenance, with 22 studies. This wide-ranging industry shows a significant research focus as it includes a variety of subsectors. The industries of 'electrical and electronics' and 'electronics' also have attracted attention with 13 studies. Technological advances and maintenance practices have been reflecting significant interest in this industry. The transport, automotive, high-speed railway, autonomous vehicles, railways, and rail transport industries represent an important research area with ten studies. The combination of subsectors such as automotive, high \begin{table}
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**Class of Repair** & **Study Number** & **Industry** & **Study Number** & **PdM Task** & **Study Number** & **Problem Type/ Approach** & **Study Number** \\ \hline Electronic and & 9 & Transport automotive, high-speed railway, autonomous vehicles, railways; rail transport & 10 & Fault detection & 12 & Clustering & 3 \\ \hline Fabricated metal & 8 & Metals and plastics; metal and metallurgy & 5 & Condition monitoring; Vibration monitoring & 9 & Reinforcement Learning & 3 \\ \hline Transport & 6 & Energy and sustainability; nuclear power; nuclear energy; renewable energy; wind energy & 5 & Anomaly detection & 4 & Unsupervised Learning & 2 \\ \hline Other machinery and equipment & 5 & Information technology; cloud services and data centers & 2 & Production quality prediction & 1 & The others & 16 \\ \hline Motor vehicles & 3 & Electric vehicle battery technology & 2 & Product liecycle management & 1 & & \\ \hline Machinery and equipment & 3 & Medical; medical devices and healthcare services & 2 & Component fatigue strength prediction & 1 & & \\ \hline Transport & 2 & Building and construction; architecture; engineering, vehicle & 2 & PdM system by a digital intelligent assistant & 1 & \\ \hline Computers and communication & 1 & Hydraulics & 2 & Blockchain framework for PdM & 1 & \\ \hline Industrial machinery and equipment & 1 & Large service management & 1 & A big data analytics framework & 1 & \\ \hline Buildings and other structures & 1 & Infrastructure; pumping systems; marine, textile; logistics and parcel delivery; steel strip processing chemical industry, aviation, home energy management & & Post-prognostic decision & 1 \\ \hline \hline \end{tabular}
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Table 3: _Cont._speed rail, and autonomous vehicles shows a wide range of topics covering various aspects of this industry. The industries of'metals and plastics' and'metal and metallurgy' have five studies. The energy and sustainability, nuclear power, nuclear energy, renewable energy, and wind energy industry is also a prominent field with five studies and covers a wide range of topics related to energy sustainability. Information technology, cloud services and data centers, electric vehicle battery technology, medical, medical devices and healthcare services, large service management, building and construction, hydraulics, and architecture, engineering, construction, and facility management industries are important industries represented with two studies.