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681.
682.
微表处技术在高速公路沥青路面养护中是一种功能完善、经济有效的预防性养护措施。该文以宣广高速沥青路面微表处在车辙处治方面的施工实践,介绍了微表处配合比的试验经验及施工的主要技术要求,供从事沥青路面养护施工的同行参考。 相似文献
683.
PTC管桩处理路段在造价增加不多的情况下,获得了比水泥土搅拌桩和排水固结法更好的处理效果和质量可控性。该文通过工程实例,对PTC管桩设计进行了归纳与总结。 相似文献
684.
阐述了科学发展观与高速公路养护工作的关系,介绍了高速公路预防性养护的主要方法,提出了用科学发展观"以人为本"、"全面、协调、可持续发展"的理念指导开展高速公路养护工作的思路。 相似文献
685.
In view of fuzzy and unstable images received in video capsule endoscopy, and the poor communication effect, an improved radio frequency (RF) transmission circuit module with low power consumption and helix antenna is designed to improve the performance of video transmission and to extend the working time of the capsule. Simulation and analysis of the circuits and antenna with HFSS12 and ADS2011 software are highlighted. Video capsule endoscope prototypes are made and evaluated to verify the feasibility of the proposed design. In vitro tests and animal experiments show that the results of the antenna tests basically meet the simulation, and the power consumption of RF circuit is 15.9mV. The video capsule endoscope works well with the receiver with multiple receiving antennas, and the working time is more than 9 h. It can realize the wireless transmission of the video data, and images received are clear and stable in comparison with the previous designs. 相似文献
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针对目前我国高速公路半刚性基层施工的质量控制难点,结合河南省化庄(省界)至新蔡段高速公路半刚性基层施工过程中质量控制的实际情况,对DTJ水泥稳定土动态质量监控系统的首次成功应用进行探讨。 相似文献
689.
滑行艇高速航行时的数值模拟(英文) 总被引:1,自引:0,他引:1
Planing vessels are applied widely in civil and military situations.Due to their high speed,the motion of planning vessels is complex.In order to predict the motion of planning vessels,it is important to analyze the hydrodynamic performance of planning vessels at high speeds.The computational fluid dynamic method(CFD) has been proposed to calculate hydrodynamic performance of planning vessels.However,in most traditional CFD approaches,model tests or empirical formulas are needed to obtain the running attitude of the planing vessels before calculation.This paper presents a new CFD method to calculate hydrodynamic forces of planing vessels.The numerical method was based on Reynolds-Averaged Navier-Stokes(RANS) equations.The volume of fluid(VOF) method and the six-degrees-of-freedom equation were applied.An effective process was introduced to solve the numerical divergence problem in numerical simulation.Compared with experimental results,numerical simulation results indicate that both the running attitude and hydrodynamic performance can be predicted well at high speeds. 相似文献
690.
迎浪规则波中波浪增阻和船体垂向运动的数值预报(英文) 总被引:1,自引:0,他引:1
The numerical prediction of added resistance and vertical ship motions of one ITTC (International Towing Tank Conference) S-175 containership in regular head waves by our own in-house unsteady RANS solver naoe-FOAM-SL JTU is presented in this paper. The development of the solver naoe-FOAM-SJTU is based on the open source CFD tool, OpenFOAM. Numerical analysis is focused on the added resistance and vertical ship motions (heave and pitch motions) with four very different wavelengths (0.8Lpp≤λ≤1.5Lpp) in regular head waves. Once the wavelength is near the length of the ship model, the responses of the resistance and ship motions become strongly influenced by nonlinear factors, as a result difficulties within simulations occur. In the paper, a comparison of the experimental results and the nonlinear strip theory was reviewed and based on the findings, the RANS simulations by the solver naoe-FOAM-SJTU were considered competent with the prediction of added resistance and vertical ship motions in a wide range of wave lengths. 相似文献