# Relief Aircraft Dispatch Strategies Based on Different Levels of Information Sharing Systems
## 7 Conclusions  
In air rescue activities during a large-scale disaster, different communication devices among the different stakeholders, such as whiteboard, satellite telephone, and real-time devices (D-net), are utilized for sharing information. This study aimed to quantify the effect of the different information-sharing systems on the efficiency of air relief activities.  
First, we defined an information-sharing system in three levels: no communication among different entities; part of the entities could be in contact (usually rescue shelters and rescue centers), and real-time communication among all entities. Second, based on the properties of different information-sharing levels, we proposed different transportation methods. Third, we utilized an agent-based simulation to embed different aircraft dispatchment methods into air relief activities. Finally, by comparing different methods under different scenarios of the D/C ratio and Gini coefficient (demand imbalance), we analyzed the influence of the different communication systems on relief activities.  
The key findings of this study are:  
1. The higher the level of the information-sharing system, the better the efficiency of relief activities. This is proved by quantitative analysis.
2. Even if the total distribution of demand affects the effectiveness of transportation methods, when handling an imbalanced distribution of demand, the more flexible methods, such as multiple destinations or dynamic routing, have a higher performance, especially for the indicator of waiting time.
3. The total demand number can also affect the effectiveness of transportation methods. For example, when the D/C ratio is larger than 1, the methods in levels two and three have an almost identical performance. In this case, the simple and commonly used method \"one flight one destination\" is sufficient. All three findings are demonstrated for the first time in published scientific literature. Hence, we suggest:  
1. To improve the preparedness for disaster response, advanced communication devices should be used in relief activities as much as possible, especially in some areas where the population distribution is uneven.
2. Considering the possibility of an uneven injury distribution, a disaster relief authority or local government can design optimal transport methods in advance to make the best use of relief resources.
3. Our results show that when the number of injuries is evenly distributed and either equal to slightly more than the total injuries, the basic and commonly used method \"one destination\" is also effective. Therefore, to reduce the complexity of rescue whilst maintaining efficiency, it is recommended that the location distribution of rescue shelters should be designed considering the population distribution.  
In this study, for the overall model, the process of air rescue was simplified, and the flight routing only included airport and rescue shelters, without considering aircraft refueling in the airport and other missions. Only one transport method was called for each simulation, without considering the combination of different transport methods; For the input data, although we used different coefficients to simulate the different scenarios of demands in the affected area; in each scenario the input of demand was uncharged for several hours. These constitute the limitations of our research. In our future work, we plan to introduce practical disaster data and demand variations with time to analyze the optimal air transport method in more complex practical situations.  
Conceptualization, Q.W. and T.H.; methodology, Q.W.; formal analysis, Q.W.; writing--original draft preparation, Q.W.; writing--review and editing, T.H.; supervision, T.H. All authors have read and agreed to the published version of the manuscript.  
This research received no external funding.  
Not applicable.  
The authors declare no conflict of interest.