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871.
强夯法在兴城临海产业区中的应用 总被引:1,自引:0,他引:1
兴城临海产业区基础设施工程中,填方厚度在3~6m,回填土材料为山皮土,为了减少路基沉降,对道路路基范围内进行强夯处理,并进行相应的检测,满足路基设计要求,强夯处理软弱路基优点是经济、便捷、安全。 相似文献
872.
为保证隧道塌方时施工人员有足够的逃生空间,结合具体工程,介绍了隧道逃生管设计要点,并对其在冲击荷载作用下的动力响应进行了弹塑性数值模拟。研究表明,逃生管变形随着落石尺寸的增大而增大,随着逃生管壁厚的增大而减小,随着与逃生管端部距离的增大而减小。 相似文献
873.
874.
D. -J. Kang 《International Journal of Automotive Technology》2009,10(2):205-210
In the last decade, vehicle identification systems have become a central element in many applications involving traffic law
enforcement and security enhancement, such as locating stolen cars, automatic toll management, and access control to secure
areas. As a method of vehicle identification, license plate recognition (LPR) systems play an important role and a number
of such techniques have been proposed. In this paper, we describe a method for segmenting the main numeric characters on a
license plate by introducing dynamic programming (DP) that optimizes the functionality describing the distribution of the
intervals between characters, the alignment of the characters, and the threshold difference used to extract the character
blobs. The proposed method functions very rapidly by applying the bottom-up approach of the DP algorithm and also robustly
by minimizing the use of environment-dependent image features such as color and edges. 相似文献
875.
Y. Shi I.- T. Lee A. Md. Afsar J.- I. Song 《International Journal of Automotive Technology》2009,10(4):481-488
As the number of disabled people grows, independence and mobility become a priority for those individuals. To achieve this
goal, a ‘Turny-type power seat’ was developed in this study to assist a disabled person rise from a vehicle without trouble.
The design and modeling of the power seat were performed using AutoCAD and CATIA software. The major motions of the power
seat system are swiveling, sliding, and extending, which are accomplished primarily by DC motors, chains, and gears. Most
of the power seat parts were made from mild steel. Welding technology was used throughout the frame fabrication. To ensure
the safety and stability of the power seat, various tests were performed, and the results analyzed. The static analysis of
the power seat was carried out by ANSYS 11.0. The results showed that the power seat conformed to the Americans with Disabilities
Act (ADA) standards. The durability test was performed by repeatedly rotating and sliding the power seat under loading conditions.
Dynamic crash simulation was carried out using the LS-DYNA software. The durability test ensured a longer life of the power
seat, while the crash analysis showed a small rotational distortion that was not harmful to passengers. However, the front
seat had a slightly larger forward displacement, which was not comfortable for passengers. Therefore, further modifications
of the power seat should be done to improve the performance, with attention given to the reduction of the forward displacement
in the event of a crash. 相似文献
876.
灰色关联法分析沥青混合料高温稳定性影响因素 总被引:1,自引:0,他引:1
采用灰色系统关联度分析法从数学的角度研究了沥青混合料各组成因素与动稳定度之间的关系.分析结果表明,粗集料的含量对沥青混合料的动稳定度影响较大,其次为沥青含量,这对沥青混合料研究以及设计有一定的指导意义. 相似文献
877.
878.
To investigate the seismic performance of the double-row pre-stressed anchor piles (DRPAPs) on the Yuxi-Mengzi railway, FLAC3D was used to construct a three-dimensional model. Using Koyna earthquake records as input motions, dynamic time-history analyses were carried out. In the analyses, we compared earth pressure on the front and back of the piles and deformation of the piles under different seismic forces with or without anchor cables. With the anchor cable present, the earth pressure on the back of the pile s free section increases, but that on the back of the pile s anchorage section decreases. Also, with anchor cables, the earth pressure on the front of the upper pile decreases, and that on the back of the lower pile decreases. 相似文献
879.
A vehicle-track-bridge coupling dynamics model was built based on the theory of vehicle-track coupling dynamics. Using this model, a comparison was made between the dynamic response of an elastic sleeper ballasted track and a common sleeper ballasted track on bridge under the same working conditions. The results show that laying elastic sleepers on the bridge could solve the problem of large track stiffness caused by a thin ballast thickness, and improve the dynamic response of the bridge. This is beneficial to train operation safety and riding comfort. 相似文献
880.