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The problem always exist in foundation pit engineering that the support axial force can not be regulated in the pit system in real time.According to setting the axial force compensation system,the problem would be solved perfectly and efficiently,realizing the fact control and adjust the support axial force and stability. The axial force compensation system which is constituted by jacks distributed in the pit has been confirmed the significant role to control foundation pit deformation and internal force monitoring combined with practical engineering

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In order to realize the miniaturization of fuze safety mechanism, a novel MEMS safe and arm is proposed through concept, analysis, design and initial prototyping. A microscale inertial mechanical logic for mechanical safe and arm functions in the form of sliders, springs, and locks that interact on a planar substrate in response to setback acceleration and centrifugal force to thereby arm the fuze, and the bulk fabrication process were analyzed. The safety criteria, design principles, modeling and simulation methods for arming slider, setback lock, and arming lock are introduced. Air gun testing demonstrates the feasibility of MEMS safe and arm device and the validity of the design method.

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The nitrogen dynamics of plants can be quantified using the variation in their δ 15 N level. This reveals details of plant physiological characteristics and the relationship between plants and their growth conditions. To better understand plant nitrogen dynamics and the effects of external temperature changes on their nitrogen isotopic composition, we investigated the δ 15 N characteristics in Triticum aestivum and its mother soils during the plant's life cycle. We found that under field conditions, the plant's leaves and roots δ 15 N significantly changed. The δ 15 N values in Triticum aestivum changed from -1.6‰ to -8.1‰ for leaves and from -2.0‰ to -8.8‰ for roots, respectively. δ15 N values for both, the leaves and roots were positively correlated with temperature. However, the foliar δ 15 N corresponded more strongly to air temperature, while the root δ 15 N corresponded to soil temperature. δ 15 N values of leaf and root both changed around 0.2‰ in response to a 1 degree change in temperature. Plant roots or shoot material cannot reflect the whole plant δ 15 N values due to a considerable difference between the δ 15 N values of root and leaf. However, the variations in leaf and root δ 15 N provide useful proxies to trace seasonal plant nitrogen cycles.