# Robust Simulation of Cyber-Physical Systems for Environmental Monitoring on Construction Sites
## 4 E-CPS Modeling and Uncertainty-Factor Identification
### Creation of Uncertain Scenarios  
The E-CPS model integrates man-machine materials, reasoning, control, and evaluation [52]. It has a series of reasoning calculation processes, and the calculation results could be affected by personal experience and subjective judgment. The E-CPS model integrates reasoning, control, and evaluation and confronts uncertainties in different layers of the E-CPS model. The perception layer is composed of controllers and network nodes responsible for collecting the construction site environmental data such as PM10, PM2.5, noise, temperature, and wind speed, using sensor components and video monitoring. The middle layer in the E-CPS system architecture is the transportation layer, which connects the perception  
\begin{table}
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**Rule** & **Jena Rules** & **Early Warning** \\ \hline Rule 1 & & [(?x rdf:type & \\  & [[http://www.owl-ontologies.com/E-CPS.owl](http://www.owl-ontologies.com/E-CPS.owl)]([http://www.owl-ontologies.com/E-CPS.owl](http://www.owl-ontologies.com/E-CPS.owl))\#PM10 & \\  & (accessed on 24 August 2022))(?x & \\  & [[http://www.owl-ontologies.com/E-CPS.owl](http://www.owl-ontologies.com/E-CPS.owl)]([http://www.owl-ontologies.com/E-CPS.owl](http://www.owl-ontologies.com/E-CPS.owl))\#hasvalue & \\  & (accessed on 24 August 2022)) + \({}^{*}\)greaterThan(?y,150) \({}^{*}\) + & \\  & \(\text{``}\)-?(? layer and the fusion layer. It is responsible for information transmission using wired networks, wireless sensor networks, and WLAN. The upper layer is the fusion layer, in which data fusion of multiple different point sensors is performed for a consistent description of the same object. The top layer is the decision-making layer, which is responsible for data processing and computing decisions, as well as performing user interaction. Based on the E-CPS framework and the on-site investigation on construction sites, this study identifies the uncertainty factors in the proposed model and then constructs typical uncertainty scenarios, which make contributions to performing robust design and simulation. Uncertain scenario 1: The perception layer data of the E-CPS has some shortcomings such as low data quality, and poor stability and timeliness. Considering that wrong data will directly lead to wrong decision-making, four categories of errors that occur in the sensor exist: (1) large value, i.e., the monitoring data deviates from the average value and swiftly returns to the normal value. In general, the oversized data are generated under severe circumstances such as rainy and snowy days, instrument failures, unstable gateways, and interference with transmission signals. (2) Constant value. It is revealed that the data remain unchanged in a certain period. This is because the constant value of the monitoring data is the crash of the sensor processing device. (3) Zero value. This is revealed in the fact that the platform data continue to be zero for a certain period. (4) The dust/noise monitoring data are clearly lower than those of the surrounding environment. Uncertain scenario 2: The construction site is equipped with more than two monitoring points. The values of similar sensors at each monitoring point differ because of the large area of the construction sites. When the green construction helps the evaluation of the difference between the monthly average concentration of the TSP and the urban background value, and the environmental noise at night, the project with multiple monitoring points requires multiple TSP sensor data fusions, and therefore the sensor data fusion is measured. Due to insufficient sensor accuracy, network noise, and other influencing factors, the monitoring data are under uncertainty conditions. Uncertain scenario 3: The environmental monitoring and evaluation indicators also include qualitative indicators, which require experts scoring based on on-site surveillance videos. However, the evaluation value provided by experts has certain uncertainty, leading to inconsistent evaluation results among the experts.