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61.
基坑支护设计的弹性抗力法 总被引:1,自引:0,他引:1
本文对基坑支护设计中常用的设计方法作了评述 ,阐述了弹性抗力法的基本原理 ,对计算时土压力分布模式的选择问题和多支撑板桩墙计算模型位移协调问题给出了明确答案 ,最后通过实例分析阐明了采用弹性抗力法进行基坑支护设计的思路和步骤。 相似文献
62.
为了测量EAST磁体位移的变化,采用计算机视觉处理方法构筑三维测量模型,利用边缘检测算法对图像采集系统获得的图片进行识别和检测,最终得出位移的变化值,从而可以在等离子体磁场位形控制中通过补偿修正这些变化。该测量方法解决了EAST装置冷质磁体位移测量的难题。 相似文献
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65.
Effects of supply air temperature and inlet location on particle dispersion in displacement ventilation rooms 总被引:1,自引:0,他引:1
The effects of supply temperature and vertical location of inlet air on particle dispersion in a displacement ventilated (DV) room were numerically modeled with validation by experimental data from the literature. The results indicate that the temperature and vertical location of inlet supply air did not greatly affect the air distribution in the upper parts of a DV room, but could significantly influence the airflow pattern in the lower parts of the room, thus affecting the indoor air quality with contaminant sources located at the lower level, such as particles from working activities in an office. The numerical results also show that the inlet location would slightly influence the relative ventilation efficiency for the same air supply volume, but particle concentration in the breathing zone would be slightly lower with a low horizontal wall slot than a rectangular diffuser. Comparison of the results for two different supply temperatures in a DV room shows that, although lower supply temperature means less incoming air volume, since the indoor flow is mainly driven by buoyancy, lower supply temperature air could more efficiently remove passive sources (such as particles released from work activities in an office). However, in the breathing zone it gives higher concentration as compared to higher supply air temperature. To obtain good indoor air quality, low supply air temperature should be avoided because concentration in the breathing zone has a stronger and more direct impact on human health. 相似文献
66.
Marko Miladinovi? Sladjana Miljkovi? Predrag Stanimirovi? 《Applied mathematics and computation》2011,218(7):3131-3143
We introduce a new algorithm based on the successive matrix squaring (SMS) method. This algorithm uses the strategy of ε-displacement rank in order to find various outer inverses with prescribed ranges and null spaces of a square Toeplitz matrix. Using the idea of displacement theory which decreases the memory space requirements as well as the computational cost, our method tends to be very effective for Toeplitz matrices. 相似文献
67.
A new horn for high displacement amplification is developed. The profile of the horn is a cubic Bézier curve. The ultrasonic actuation of the horn exploits the first longitudinal displacement mode of the horn. A design method of the horn using an optimization scheme and finite element analyses is developed. Prototypes of the horns are manufactured by a numerical control machining process. Performances of the proposed horn have been evaluated by experiments. Experimental results of the harmonic response of the fabricated horn confirm the effectiveness of the design method. The displacement amplification of the proposed horn is 71% higher than that of the traditional catenoidal horn with the same length and end surface diameters. 相似文献
68.
Black-grating-effect of SLM on the displacement measurement based on phase-coded target joint transform correlators(PCTJTC) is discussed. Displacement measurement technology based on PCTJTC is proposed. Black-grating-effect is explained and the impact of a pixel's fill factor is discussed. Pixel segmentation is elaborated and simulation results are given. It is shown that black-grating-effect has brought errors to the detection precision. The optical efficiency is higher when the fill factor is bigger, and the intensity distribution of the spectrum moves closer toward the 0th fringe, which brings down the CCD's need of high resolution. 相似文献
69.
Z.H. Yang Z.W. LiL. Liu L.B. Kong 《Journal of magnetism and magnetic materials》2011,323(21):2674-2677
CoCu nanowires were fabricated in anodic alumina templates by a simple metal displacement deposition method and the as-deposited samples were subsequently annealed at 400 °C in vacuum. The CoCu nanowires are 80 nm in diameter and 50 μm in length. The aspect ratio (ratio of length to diameter) is larger than 600, which results in distinctive magnetic anisotropy. Enhanced coercivity (about 2245 Oe) and large squareness of 92% have been observed in the annealed samples. 相似文献
70.
Lens distortion practically presents in optical imaging system using in two-dimensional digital speckle correlation measurement (2D-DSCM) system, and gives rise to additional errors in the displacement and strain measurement. Camera calibration procedure is performed to obtain the coefficients of radial distortion and tangential distortion. The corrected displacement fields can be calculated using the distortion coefficient. The influence of distortion on displacement and strain measurement errors in experiment is further discussed. The three-point bending test result shows that the camera lens calibration method can effectively eliminate the effect of lens distortion and improve displacement and strain measurement accuracy. 相似文献