Fast determination of meso-level mechanical parameters of PFC models

To solve the problems of blindness and inefficiency existing in the determination of meso-level mechanical parameters of particle flow code (PFC) models, we firstly designed and numerically carried out orthogonal tests on rock samples to investigate the correlations between macro-and meso-level mechanical parameters of rock-like bonded granular materials. Then based on the artificial intelligent technology, the intelligent prediction systems for nine meso-level mechanical parameters of PFC models were obtained by creating, training and testing the prediction models with the set of data got from the orthogonal tests. Lastly the prediction systems were used to predict the meso-level mechanical parameters of one kind of sandy mudstone, and according to the predicted results the macroscopic properties of the rock were obtained by numerical tests. The maximum relative error between the numerical test results and real rock properties is 3.28% which satisfies the precision requirement in engineering. It shows that this paper provides a fast and accurate method for the determination of meso-level mechanical parameters of PFC models.

Code mechanical solidification and verification in MEMS security devices

The virtual machine of code mechanism （VMCM） as a new concept for code mechanical solidification and verification is proposed and can be applied in MEMS （micro-electromechanical systems） security device for high consequence systems. Based on a study of the running condition of physical code mechanism, VMCM＇s configuration, ternary encoding method, running action and logic are derived. The cases of multi-level code mechanism are designed and verified with the VMCM method, showing that the presented method is effective.

An Efficient Quantum Key Distribution Protocol with Dense Coding on Single Photons

Combined with the dense coding mechanism and the bias-BB84 protocol,an efficient quantum key distribution protocol with dense coding on single photons(QDKD-SP)is proposed.Compared with the BB84 or bias-BB84 protocols based on single photons,our QDKD-SP protocol has a higher capacity without increasing the difficulty of its experiment implementation as each correlated photon can carry two bits of useful information.Compared with the quantum dense key distribution(QDKD)protocol based on entangled states,our protocol is more feasible as the preparation and the measurement of a single-photon quantum state is not difficult with current technology.In addition,our QDKD-SP protocol is theoretically proved to be secure against the intercept-resend attack.

Analysis on small-earthquake composite fault plane solutions from 1961 to 1999 in Xinfengjiang reservoir area

To understand the earthquake characteristics in Xinfengjiang (XFJ for short) reservoir area, we collected the small earthquakes occurred in the area from 1961 to 1999. We segmented this 40-year period, parted the research region and calculated the composite fault plane solution of each block, disscussed the effect characteristics of stress field of water pressure using Mohrs stress circle. The final result shows that the main rupture pattern was very different before and after the M = 6.1 main shock, changing from strike slip to normal rupture. The maximum principal stress axes of composite fault plane solutions are characterized by synchronous change with water level.

Network Coding-Aware Routing Protocol in Wireless Mesh Networks

Network coding mechanisms, such as COPE, can improve network throughput effectively in Wireless Mesh Networks（WMN）. While the Hybrid Wireless Mesh Protocol（HWMP） is suitable for WMN, its extension with COPE does not provide any added benefits; specifically, HWMP cannot establish paths with more coding opportunities. As a result, the advantages of network coding cannot be exploited sufficiently. This paper proposes improvements upon HWMP with a new, network Coding-Aware routing protocol（CAHWMP） for WMN. In the CAHWMP protocol, we propose a coding criterion based on data streams to devise an algorithm for actively detecting coding opportunities during path discovery. CAHWMP subsequently establishes paths using the codingaware routing metric, which can balance channel resource consumption and the gain due to sharing resources introduced by network coding. Simulation results show that CAHWMP can establish paths with more coding opportunities; as a result, it improves network performance such as network throughput.