# A Methodology for the Design of Application-Specific Cyber-Physical Social Sensing Co-Simulators
## 2 State of the Art
### Particularization of the General Simulation Model and Simulation Lifecycle
#### 3.3.2 Simulation Lifecycle  
Depending on the type of the simulations being performed in the designed co-simulator, the simulation lifecycle may vary (more steps could be added, for example). The steps included in the simulation lifecycle are going to affect, overall, the fourth step in the methodology, dedicated to the \begin{table}
\begin{tabular}{c c} \hline \hline
**Application** & **Actions** \\ \hline Validation of ambient intelligence systems & A more specific definition of the physical world (ambient) is necessary. In particular, physical laws for the evolution of relevant phenomena should be modeled. Besides different types of people should be also considered (depending on if they present special needs, incapactives, etc.). \\ \hline Development of IoT systems & The concept of “service” should be added in the simulation model, and a more exhaustive description of the different types of devices also would be desirable (in particular, a description of the interfaces is very important in IoT scenarios). \\ \hline Social research & Most elements in the cyber world can be removed (it is enough to include the concept of “device”). On the other hand, social world must be extended, including different personal and social states, different types of interactions among people and the social evolution aws. \\ \hline Crowd management & A detailed model for “physical object” may be important. Models for walls, doors, buildings, etc. are critical in order to manage people in the most adequate way in addition, models for the different emotions and their propagation in crowds must be considered. \\ \hline Social sensing & Different types of sensors have to be considered, so the model must include all of them. \\ [86; 87; 88; 89; 90] & Besides, the social world requires a more exhaustive description as mentioned in the case of “social research” and “crowd management”. \\ \hline \hline \end{tabular}
\end{table} 
Table 7: Criteria for the creation of the simulation model. Figure 6: Base CPSS simulation model. interaction with users. For example, if all the simulations to be performed only address one goal, no step for \"goal specification\" is needed, and no interface dedicated to this step is required. In general, designing the most adequate lifecycle is much easier (almost elemental) than building the simulation model. Next, a complete generic simulation lifecycle is described, from which different steps can be removed (if necessary), or where new states may be defined. The creation of the particularized simulation lifecycle is very simple: if the tasks associated with a certain state described below do not have to be executed, this state is removed; if new tasks have to be added, new states should be defined. Co-simulation environments are often used to test how humans relate to devices and other infrastructure objects. Simulations showing specific aspects of these relations are executed and redefined multiple times to retrieve knowledge about users and devices. The process is represented in Figure 7 and the quality assessment [128] of every step is described below. **Goal specification**: Stakeholders meet to determine the specific problem to solve, capturing this information by field studies and/or other requirement acquisition techniques. The research problem is formally and clearly formulated. One goal commonly pursued in simulations integrating social behavior and device interaction is to check the functioning of a control system (a device or set of devices that manages and regulates the behavior of other systems in the smart environment), analyzing if this system correctly takes into account its execution context. This is a prior step to define the simulation model associated to this system, as analyzed goals can be used to model what kinds of experiments are desirable for the particular problem and the type of situations considered. **Definition of simulation model**: Social behavior and social interactions with devices and the control system must be integrated into the simulation model.