Table 2 Status of research on DT application systems

Unit-level DT

Aerospace

[43, 66,67,68]

Life prediction

Damage prediction

Bridge construction

[69, 70]

Building structural health monitoring

Life prediction

Transportation

[71,72,73]

Virtual testing

Vehicle health monitoring

Healthcare

[74, 75]

Surgical or medical simulation

Process-level DT

Intelligent manufacturing

[12, 76,77,78,79,80,81,82]

Production process simulation

Diagnosis of machine faults

Monitoring and forecasting of production tools or machines

Human-machine collaboration

[55, 83,84,85,86,87]

Optimization of industrial human–machine collaboration

Metal smelting

[88, 89]

Production process simulation

Physical networks

[90,91,92]

Implementation of Industry 4.0, IoT and cyber-physical production systems

System-level DT

Smart factory

[93,94,95,96,97]

Improving the efficiency of shop floor manufacturing equipment

Optimizing production planning and resource allocation

Operational monitoring and troubleshooting

Training and education

[98,99,100,101]

Optimizing distance learning or online teaching

Energy and power

[58, 102,103,104,105,106]

Optimizing production planning and resource allocation

Operational monitoring and troubleshooting

Intelligent transportation

[107]

Increasing traffic condition awareness to aid driving decisions