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In this work, polymer-bonded sugars were used as a substitutive material for polymer-bonded explosives (PBXs). Their production process and damage mechanism under compressive process were analysed....

Nucleation and growth of microcracks is a dominant form of damage evolution in polymer bonded explosives (PBXs). The mechanism of such a damage evolution of PBX under impact loading was analyzed in this study. For safety and convenience, a PBX substitute material was firstly designed by mixing sugar and a new agglomerant to form polymer-bonded sugar materials (PBS). The dynamic test was carried out by SHPB technique at different impact velocity. The cracks' nucleation of PBS was analyzed by means of Micromechanics. The results indicate that the material possesses capability to adjust its microstructure, and the dynamic tensile stress at the surface of defects induces the microcracks' nucleation.

Acousto-optic tunable filter (AOTF) has the advantages of small size, good stability, wide range of wavelength scanning, quick modulation speed and so on. So AOTF is widely used in spectral imaging. But the detection of spectral polarization imaging is seldom found by using AOTF individually., Anew method of spectral polarization imaging based on dual-AOTFs is proposed. This method shows that the incident light is firstly divided into two beams by splitting mirror, and then two beams of light are through two AOTFs respectively, and the polarization direction of +1 diffraction order formed by AOTF is at a 45° against the other. The intensity of 0°, 45°, 90°and 135° can be obtained by ±1 diffraction orders of dual-AOTFs. Finally, the Stokes parameters are obtained by ±1 diffraction orders imaging of dual-AOTFs. They are S0 (the sum of light intensity between 0° and 90°), S1(the difference of light intensity between 0° and 90°) and S2 (the difference of light intensity between 45° and 135°). The target degree of linear polarization (DoLP) and angle of linear polarization (AoLP) is realized by corresponding theoretical formula. Furthermore, the polarization imaging of different wavelengths is realized with frequency sweep of dual-AOTFs so as to ultimately detect the spectral polarization imaging. The experiment has been verified through polarization imaging of three different lights, such as λ=500 nm, λ=550 nm and λ=600 nm.

This paper introduces a intuitionistic fuzzy to describe the aviation maintenance safety culture on the influence of group safety behavior ,then put forward Muti-Agent modelbased on intuitionistic fuzzy theory (IFT).At last,construction the influence mechanism of aviation service safety culture on group behaviors, The model gets better results through a simulation.

Similarity measure for multivariate time series is a hot topic in the area of data mining. However, existing algorithms of similarity measure cannot resolve the contradiction between matching accuracy and computational complexity. We propose a novel similarity measure for multivariate time series. First, important points are extracted from multivariate time series. Then, a similarity measure based on dynamic time warping is proposed. Finally, the performance of our proposed method and other popular approaches is compared. The experimental results show that the proposed method can effectively measure the similarity of multivariate time series at relatively lower computational cost.

A polymer-bonded explosive substitute material (PBX) composed of sugar granules and polymer binder was fabricated with a weight proportion of 90:10. Static Brazilian tests accompanied by high-speed photography, digital image correlation (DIC) technology, and dynamic mechanical analysis (DMA) were carried out. The tensile stress-strain relation is quasi-linear until failure with a tensile strength of about 0.89 MPa, elastic modulus of 35 MPa, and Poisson’s ratio of 0.392. Microscopically, interfacial debonding and intergranular fractures are the main mechanisms of damage. By DMA, the storage modulus and tan δ show a strong dependence on temperature and less dependence on frequency; the glass transition temperature is found to be about 50°C. These results are helpful for understanding the behavior of PBX under tensile and dynamic loading.

In view of the existing relatively cumbersome polarization measurement method of using liquid crystal phase variable retarder (LCVR) and acousto-optic tunable filter (AOTF), a new strategy of spectrum and polarization measurement is put forward. This method removed mechanical movement and reduced the amount of phase delay from four groups to two groups. This method realizes the spectrum and polarization measurements by measuring the plus and minus 1 level diffraction light of the system with two LCVR, one AOTF and two same version detectors. For the polarization measurement of a particular wavelength, the computer controlled LCVR driving voltage to achieve the required phase delay in accordance with the requirements of the wavelength, it also controlled the driving frequency to implement the required wavelength selection of AOTF. Because of the different driving frequencies of AOTF corresponding to the different wavelengths, so it can get the spectral information by scanning the whole frequency bands, In this paper detailed principles are deduced and the polarization model of AOTF is analyzed, it also deduced the measurement formula of I, Q, U in the corresponding Stokes parameter through the theoretical calculation Muller matrix of the LCVR and AOTF. Finally it analyzed and simulated the measurement error of the whole system which was caused by the tiny deviation of phase delay, the simulation results show that relative error3% when the phase delay amount within the range of ±π/100. This experiment proved the feasibility and accuracy of the measurement system, the results show that the error of the measuring system overall6%. This study provides a new method of polarization measurement which is simple, feasible and precise, it has important application value.

With the rapid development of network-based office technology, the traditional way of management and work of the aviation equipment repair mid-institution results in low efficiency. The repair business process optimization of the aviation equipment repairing factory can effectively improve the repair efficiency, and ensure the readiness and re-take off rate of the aviation equipment. First, the model of aeronautical component repair business process is built using the Time-Petri Net. The optimization model is built by making those optimizing policies on to the model. Then the special characteristic which is moving branches of Petri net can bring the model to reach the optimal strategy, and the scale of the net can be reduced by using the folding effect of colored Petri net. With these optimizations, a Color-Time-Petri net model for Aviation Component repair business process could be established. Finally, through comparative analysis of simulation results it is found that the optimization model improves the efficiency by 50% of repairing without affecting the quality, also the stability of the processes running is enhanced.

To investigate the feeding patterns of infants in Huining County, Gansu Province, an economically undeveloped county in China, so as to provide scientific evidence for nutritional intervention.By cluster sampling based on the area distribution and the economic state, 437 children from 7 different areas in Huining County, Gansu Province were enrolled. A questionnaire on the feeding patterns within 24 months of age was completed by the caregivers. The addition of nutrient supplements (calcium, zinc, ferri, vitamin AD, etc.) during the last year was investigated using the food frequency questionnaires.The average percentages of breast feeding, mixed feeding and artificial feeding were 45.3%, 40.5% and 14.2% respectively. Delayed introduction of complementary food was the most common. Formula powder was added earliest, at age of 6.4 months. The meats were added latest, at age of 17.2 months. Only 66.8% of infants received an addition of complementary food at age of 4-6 months. Grains, vegetables, fruits and eggs were common complementary additional diets, but fishes and shrimps were seldom provided. The proportion of nutrient supplement use was low. The choice of nutrient supplements in urban districts mainly depended on the physicians' suggestions, but in rural area it depended on the caregivers' experience and media advertisements.The feeding patterns for the infants are not reasonable in Huining County, Gansu Province. It is important to provide nutritional education and reasonable feeding program for caregivers from economically undeveloped areas.