## 6 Discussion
The difference with respect to our work is that they focused on mobile environment domains where the information system can be interpreted at runtime. In addition, the reconfiguration of system at runtime is not considered. [PERSON] et al. [27] proposed a distributed model to capture the states of different nodes of cyber-physical systems (CPSs) at runtime. A time triggered protocol is used to update the models. They used a publish-subscribe middleware for communications. The monitoring system captures the critical situations of interest. The focus of this work is not on the system reconfiguration at runtime. [PERSON] et al. [20] proposed a temporal property language for runtime monitoring of any kind of executable discrete event model supported in a development framework. This work is independent on the modeling language or the programming language. Todeal with reconfiguration in live programming, [PERSON] et al. [28] used incremental deltas with respect to the original code of texture domain-specific model (DSLs). They applied the deltas on the running programs by migrating them based on their state, using a dynamic patch architecture. The approach does not depend on a specific programming language. It does not focus on monitoring the state of the program while applying changes. Based on the architectural pattern MAPE-K (Monitor, Analyze, Plan, Execute- Knowledge) [32] and semantic Web technologies, [PERSON] et al. [29] proposed an approach that enables the management of heterogeneous knowledge and the creation of runtime queryable models. The authors use ontologies, as a semantic technology, for the representation and management of real-world systems and their environment. The proposed approach is evaluated on the system that manages the entire IT infrastructure of the University of Bologna. In this work, the authors do not focus on a general programming language, but on concurrent Java components for the four MAPE-K phases, and the monitoring process is not based on expression inspection, but on the use of OWL ontologies. [PERSON] et al. [30] proposed an efficient parallel reasoning framework on fuzzy goal models to assess the compliance of critical requirements at runtime. They take into consideration the application logs as a fuzzified data stream to monitor these situations \begin{table}
\begin{tabular}{p{56.9 pt} p{56.9 pt} p{56.9 pt} p{56.9 pt} p{56.9 pt}} \hline \hline
**Approach** & **Modeling Technique** & **Research Objective** & **Application Domain** & **Runtime Monitoring Technique** \\ \hline Our approach & PN \& GRRs & Behavior of Python applications, runtime analysis, Python expressions, continuous change & Independent & Reflection \\ \hline [PERSON] et al. [3] & PAMELA meta-model & Runtime analysis of Java applications, continuous change & Independent & Reflection \\ \hline [PERSON] et al. [7] & DSL & Adapting architectures based on component syntax and semantics & Independent & Heuristics \\ \hline [PERSON] et al. [18] & Meta-model & Monitoring non-functional requirements & Cloud services & Monitoring \\ \hline [PERSON] et al. [19] & BPCPN Meta-model & Monitoring & Independent & Model transformation \\ \hline [PERSON] and [PERSON] [8] & AGM Meta-model & Interpreting information systems & Mobile cloud environments & Monitoring \\ \hline [PERSON] et al. [27] & Meta-model & Monitoring & Cyber-physical systems & Publish-Subscribe \\ \hline [PERSON] et al. [20] & Executable DSLs & Monitoring & Independent & Temporal property language \\ \hline [PERSON] and [PERSON] [28] & DSLs & Live programming & Independent & Model Comparison \\ \hline [PERSON] et al. [29] & Ontologies & Adaptation & Adaptive software & Semantic Web \\ \hline [PERSON] and [PERSON] [30] & Fuzzy goal models & Runtime requirement verification & Systems-of-systems & Reasoning \\ \hline [PERSON] [31] & iObserve mega-model & Architectural runtime applications & Dynamic Cloud transformations & Model transformations \\ \hline \hline \end{tabular}
\end{table} 
Table 6: Approach comparison. in over-medium and large-scale systems of systems.