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Sharding technology is one of the core technologies to solve the scalability problem of blockchain.When transactions in the P2P network are aggregated into established shards according to the rules,and the verification nodes are randomly and evenly distributed to each shard,the transactions in this shard may be congested because the transaction verification load of individual shard may far exceed the average load.In order to solve the load imbalance between shards,a shard load balancing method using state reduction is proposed.Firstly,the state reduction model is given,which allows high-performance nodes to store more adjacent states,and the node performance is roughly classified according to this model.Secondly,according to the transaction verification situation in each timeslot,unverified transactions are taken as the remaining load,which is used as the basis for adjusting the verification ability in the next timeslot.Finally,the nodes are scored and graded,and the node selection strategy is given based on the remaining load and the average score of the consensus verification node set.Nodes are allocated reasonably and randomly,and the remaining loads of high load fragments are reduced upward.Experimental verification shows that the shard load balancing method using state reduction effectively balances the unusual load of one shard without reducing the transaction verification rate of a single shard.

For the semantic consistency of the architecture dynamic behavior, a method for validating the model concordance using sprouting graph is presented. The sprouting graph is constructed from the dynamic behavior model of architecture. Then, the logical structure and temporal information is analyzed, so as to verify the logical and temporal relationship consistency of the dynamic behavior model. This method can not only verify the semantic consistency of the architecture dynamic behavior, but also give the place violating the constraints which are useful to users in exception handling and modifying dynamic models. Furthermore, it is more practical, namely sprouting graph can be used for validating the dynamic behavior consistency of models. Also, the understandability and analyzability have great advantages than traditional methods. [ABSTRACT FROM AUTHOR]

Aimed at the problem that the traditional track initiation method can not initiate the near space hypersonic target track effectively, this paper proposed one kind of track initiation method on the basis of variable wave gate. On the basis of analyzing the characters of the near space hypersonic target, and it set up sector gate, ellipse gate and partial circle gate exclusively aiming at the near space hypersonic target, and set up ellipse gate according to the previous locality and velocity information when there was no effective measurement in the sector gate, it set up the partial circle gate according to the hypothesis that the target changed its movement mode at earlier time if there was no effective measuring in the ellipse gate, to make sure that the target real measurement was in the gate, and initiated the target track by the fuzzy decision-making method. The simulation results show that this new method can initiate tracks of near space hypersonic targets effectively and improve the target track initiation rate, it has engineering application meaning. [ABSTRACT FROM AUTHOR]

The article presents a study which discusses the effectivity of connected graph-based variable structure multiple model (CG-VSMM) in calculating the traditional algorithm of VSMM model based on adaptive digraph (AD), which has been determined through Monte Carlo simulation.

ABSTRACT Immobilized Cu(OAc)2-bis(oxazolines) via hydrogen bonding by SBA-15 was applied to asymmetric Henry reaction, and good enantioselectivities were obtained (up to 83% ee) between 2-methoxybenzaldehyde and CH3NO2 in isopropyl alcohol ( iPrOH). The catalyst could be reused seven times without any obvious loss in enantioselectivity. For the first time, this facile and clean immobilization method is applied to the use of bis(oxazolines) complexes. Chirality 24:1092-1095, 2012. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Abstract: New imidazolium/pyrrolidinium-tagged Indabox ligands were designed and prepared. Catalysts based on these ligands with Cu(OAc)2·H2O were applied to the asymmetric Henry reaction using various aldehydes and CH3NO2, the products were obtained in high enantioselectivity. Specifically, (R)-1-(2-methoxylphenyl)-2-nitroethanol was obtained in 94% ee in MeOH. Furthermore, the catalyst based on 7 could be recycled at least 12 times by simple wash without an obvious loss of activity or enantioselectivity. This catalytic procedure demonstrated the potential for catalyst recyclability in the asymmetric Henry reaction. Additionally, a theoretical mechanistic study was conducted to explain the origin of the enantioselectivity. [Copyright &y& Elsevier]

Functional imidazolium ionic liquids have been developed as a new class of versatile catalysts. C2-symmetric and unsymmetric imidazolium-tagged bis(oxazoline) ligands were prepared, and the anions of the ligands were altered by ion-exchange reactions. The catalysts based on the new ligands and Cu(OTf)2 were applied in asymmetric Diels–Alder reactions between N-acryloyl/N-crotonoyloxazolidinones 15 and 1,3-cyclohexandiene/cyclopentadiene 16 in different ionic liquids and in dichloromethane (DCM). The catalysts achieved a high level of activity and enantioselectivity, as well as good recyclability: cycloadduct (S)-17ab was attained at 98% conversion and 97% ee in [Bmim]NTf2. Moreover, the catalyst could be recycled 20 times without an obvious loss of activity or enantioselectivity. By comparison, we deduced that the C2 symmetry of the new ligands was crucial for obtaining high ee values. Toxicity studies of the ligands were performed for the first time. [ABSTRACT FROM AUTHOR]

Abstract: A series of 6-substituted carbamoyl benzimidazoles were designed and synthesised as new nonpeptidic angiotensin II AT1 receptor antagonists. The preliminary pharmacological evaluation revealed a nanomolar AT1 receptor binding affinity for all compounds in the series, and a potent antagonistic activity in an isolated rabbit aortic strip functional assay for compounds 6f, 6g, 6h and 6k was also demonstrated. Furthermore, evaluation in spontaneous hypertensive rats and a preliminary toxicity evaluation showed that compound 6g is an orally active AT1 receptor antagonist with low toxicity. [Copyright &y& Elsevier]

Abstract: A series of 6-substituted aminocarbonyl benzimidazole derivatives were designed and synthesized as nonpeptidic angiotensin II AT1 receptor antagonists. The preliminary pharmacological evaluation revealed nanomolar AT1 receptor binding affinity and good AT1 receptor selectivity over AT2 receptor for all compounds of the series, a potent antagonistic activity in isolated rabbit aortic strip functional assay for compounds 6b, 6d and 6i was also demonstrated. Furthermore, evaluation in spontaneous hypertensive rats and a preliminary toxicity evaluation showed that compound 6i is an orally active AT1 receptor antagonist with low toxicity. [Copyright &y& Elsevier]