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In order to avoid the environmental emission of fossil fuels, renewable energy resources expansion trend is undeniable. This paper analyzes the possibility of cooperation between neighboring independent microgids in a smart grid with renewable resources considering the security assets and vulnerabilities. The ultimate goal is to decrease the overall security risks on the smart grid. Modeling of microgrids cooperation is formulated via a coalition game definition considering the permissible amount of their vulnerabilities. Load shedding minimization can be obtained during cyber-attack occurrence for each member of coalition microgrids. This paper presents a comprehensive algorithm for optimal coalition of neighboring microgrids based on a utility function calculation which has three major components: Budget for Attack (BA), Budget for Defense (BD) and microgrid relationship effectiveness, to contribute more understanding, microgrid relationship effectiveness formulation is developed by the introduction of friction and influence matrices. Proportional Fairness (PF) index is employed to illustrate the improvement of utility function in case of optimal coalition in comparison with non-cooperative state. Microgrids coalition optimal choice based on suggested algorithm is validated by probability attack and loss of load probability (LOLP) simulation for each microgrid before and after the coalition form. [ABSTRACT FROM AUTHOR]

In a great number of applications, it is necessary to distribute resources or tasks to agents collaborating with each other in order to maximize the social welfare of the structure they belong to. The question in these cases is how to divide in a fair way the outcome that the structure eventually earns, say money, to the participating agents. The paper faces this issue by focusing on a real-world application: the distribution of funds to Italian research structures and substructures, after a research assessment program (known as VQR) that is currently evaluating the Italian research production over years 2004-2010. A number of desirable properties for any reasonable fair division rule are identified and exemplified for the case-study application. For instance, it is argued that the money distribution should be independent of possible alternative allocations of research products, and it should consider the actual contribution of every researcher to the outcome of the structure (s)he belongs to. Moreover, the whole process starting from the preliminary phase of products selection is dealt with, in order to prevent possible strategic behaviors from researchers that may lead their structure to miss its best possible score in the evaluation process. A fair solution based on the notion of Shapley value is described and analyzed. It turns out that the proposed solution enjoys all the desirable properties of fair division rules, and it could effectively be implemented in the VQR, as well as in related division-rules applications. [ABSTRACT FROM AUTHOR]