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In recent years, with the development of modern technologies and safety science, catastrophic accidents tend to be avoided successfully. However, general accidents which cause minor loss or casualties still occur occasionally and hence become main part of all accidents. Therefore, to make effective control of general accidents, fault trees are established based on the analysis of historical general accidents. The influencing factors are roughly divided into human factors and equipment system factors. This paper focuses on human factors and the relationships between the factors and general accidents are analyzed using the improved analytic hierarchy process (AHP) and methods of risk identification. The importance of the factors is thus evaluated. Results of the evaluation are helpful to management.

In the action of bending load and axial compression, the deflection of the beam presents character of geometry nonlinear. For the thin-walled carbon fiber laminated box beam column, the beam deflections not only relate with load but also with the ply angle of layer, span width ratio. By using the method of numerical, this paper analyzed and summarized the beam deflection variation with the span width ratio, ply angle, the axial compression ratio for the simply supported laminated box beam column under the axial compression and bending load.

Considering the limited resources and data transmission redundancy of wireless sensor networks, this paper proposes a distributed data aggregation algorithm based on lifting wavelet transform (DDAA-LWT), and carries out the rational design. The algorithm distributes the computing quantity which the lifting wavelet transform requires to all network nodes, eliminates the additional computing and wireless transmission, reduces the information redundancy of network, greatly prolongs the lifecycle of wireless sensor networks. Simulation results demonstrate that the distributed data aggregation algorithm based on lifting wavelet transform (DDAA-LWT) can effectively aggregate the original sensed data and decrease the energy consumption, it significantly outperforms the data aggregation algorithm based on traditional wavelet transform (DAA-WT).

Considering the shortage of LEACH protocol, a novel dynamic multi-hop routing protocol named Balance Energy-efficient and Real-time with Reliable communication protocol based on Connected Dominant Set (BERR-CDS) is proposed in this paper. BERR-CDS protocol fully takes account of the energy consumption of an individual node and entire network, a rational transmission path from source node to sink node is searched, aiming at the network topology changes which are caused by the death of cluster head, the invalidation of cluster member nodes and new nodes joining, BERR-CDS designs the corresponding valid mechanism to respond, and it can rapidly adapt to the topology change of network. Simulation results show that BERR-CDS protocol has better performances in term of energy consumption, network lifetime and reliability, it is an ideal routing protocol in wireless sensor networks.

In the minimum electromagnetism coupling model of interaction between photon and electron, we present a effective and precise calculation on the differential cross section of Compton scattering with the help of the electron renormalized chain propagator. By comparing the result of the differential cross section of the Compton scattering with electron propagator at the tree level and the one loop level, respectively, we find that the correction of the chain diagram is better than the one-loop diagram to the differential cross section in the 10-3order.

Due to shortcoming of traditional image matching for computing the fitness for every pixel in the searching space, a new bat algorithm with mutation (BAM) is proposed to solve image matching problem, and a modification is applied to mutate between bats during the process of the new solutions updating. This new approach can accelerate the global convergence speed while preserving the strong robustness of the basic BA. The realization procedure for this improved meta-heuristic approach BAM is also presented. To prove the performance of this proposed meta-heuristic method, BAM is compared with BA and other population-based optimization methods, DE and SGA. The experiment shows that the proposed approach is more effective and feasible in image matching than the other model.

Ductility is important in the design of reinforced concrete structures. In seismic design of reinforced concrete members, it is necessary to allow for relatively large ductility so that the seismic energy is absorbed to avoid shear failure or significant degradation of strength even after yielding of reinforcing steels in the concrete member occurs. This paper aims to present the basic data for the ductility evaluation of reinforced HPC (high performance concrete) beams. Accordingly, 10 flexural tests were conducted on full-scale structural concrete beam specimens having concrete compressive strength of 40, 60, and 70 MPa. The test results were then reviewed in terms of flexural capacity and ductility. The effect of concrete compressive strength, tension steel ratio, and shear span to beam depth ratio on ductility were investigated experimentally.

To improve the accuracy of strain, the design method and technology based on the theory of double-channel parametric measurement is proposed. At last, the measuring circuit with linear conversion function is designed. Based on the theory, a measuring system is developed. The practical experimentation indicates that the theory and technology are right, and the accuracy, stability, anti-interference and reliability are excellent.