SCOOP is a concurrent programming language with a new semantics for contracts that applies equally well in concurrent and sequential contexts. SCOOP eliminates race conditions and atomicity violations by construction. However, it is still vulnerable to deadlocks. In this paper we describe how far contracts can take us in verifying interesting properties of concurrent systems using modular Hoare rules and show how theorem proving methods developed for sequential Eiffel can be extended to the concurrent case. However, some safety and liveness properties depend upon the environment and cannot be proved using the Hoare rules. To deal with such system properties, we outline a SCOOP Virtual Machine (SVM) as a fair transition system. The SVM makes it feasible to use model-checking and theorem proving methods for checking global temporal logic properties of SCOOP programs. The SVM uses the Hoare rules where applicable to reduce the number of steps in a computation.

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Based on the 30-province panel data in China during 2005-2018, this paper uses the DEA-SBM model and DEA-Malmquist model to measure rural financial efficiency and agricultural technological progress respectively and then uses the mediating effect model to analyze the linear influence. The results show that rural financial efficiency and agricultural technological progress both can inhibit agricultural carbon emissions, while agricultural technological progress plays a mediating role when rural financial efficiency influences agricultural carbon emissions. What’s more, this paper uses the threshold effect model to analyze the non-linear influence. The findings reveal that when rural financial efficiency improves, the effects of rural financial efficiency and agricultural technology advances on agricultural carbon emissions shift from promoter to inhibitor.

Power Grid in China integration running trend makes EMS(Energy Management System) at all levels of information exchange between the increasingly urgent demand. And CIM is the most important base information. In order to solve the model information differences between different EMS, this paper analyzes the current EMS model information related to the standardization of applications, from standard CIM model, the model file formats and file content model three aspects, based on interoperable standards IEC61970 process-oriented information model calibration and validation process for each part of the key technologies are discussed in detail. Through the practical application of the method validation results show that the calibration method is reasonable and correct.