Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Revisiting Digital Twins: Origins, Fundamentals and Practices   The Digital Twins (DT) has quickly become a hot topic since it was proposed.
It not only appears in all kinds of commercial propaganda, but also is widely
quoted by academic circles. However, there are misstatements and misuse of the
term DT in business and academy. This paper revisits Digital Twins and defines
it to be a more advanced system/product/service modelling and simulation
environment that combines the most modern Information Communication Technology
(ICTs) and engineering mechanisms digitization, and characterized by
system/product/service life cycle management, physically geometric
visualization, real-time sensing and measurement of system operating
conditions, predictability of system performance/safety/lifespan, complete
engineering mechanisms-based simulations. The idea of Digital Twins originates
from modelling and simulation practices of engineering informatization,
including Virtual Manufacturing (VM), Model Predictive Control (MPC), and
Building Information Model (BIM). Based on the two-element VM model, we propose
a three-element model to represent Digital Twins. Digital Twins does not have
its own unique technical characteristics; the existing practices of Digital
Twins are extensions of the engineering informatization embracing modern ICTs.
These insights clarify the origin of Digital Twins and its technical
essentials.

15
The categories of this paper are: nucl-ex
22
The categories of this paper are: chao-dyn
35
The categories of this paper are: mtrl-th
21
The categories of this paper are: adap-org
12
The categories of this paper are: nucl-th
5
The categories of this paper are: gr-qc
9
The categories of this paper are: nlin
11
The categories of this paper are: hep-lat
29
The categories of this paper are: funct-an
23
The categories of this paper are: solv-int
31
The categories of this paper are: ao-sci
20
The categories of this paper are: acc-phys
37
The categories of this paper are: supr-con
7
The categories of this paper are: hep-th
3
The categories of this paper are: physics
34
The categories of this paper are: chem-ph