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161.
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丰田佳美轿车巡航(定速)控制系统的维修 总被引:2,自引:0,他引:2
介绍了日本丰田佳美轿车巡航(定速)控制系统的结构与原理。该系统通常具有巡航(定速)、惯性滑行、恢复车速、加速及点动增(减)速等功能。阐述了该系统代码故障的维修及未显示故障症状时的维修。 相似文献
164.
SONG Zhi-ming KANG Feng-ju TANG Kai and CHU Yan-jun Marine College Northuxstern Polytechnical University Xi'''' an China 《船舶与海洋工程学报》2003,2(2):40-45
Realistic simulation of underwater scene is always difficult because of the special and complex vision effects in underwater space. Seabed is an important part of underwater environment. This paper describes the methods for seabed scene simulation based on OpenGL. It includes construction of fluetuant terrain based on the random sinusoidal algorithm, simulation of seabed flicker effect by means of circular texture mapping and generation of turbidity effect by using fog techniques. For the application based on the leading high level 3D development environment-Vega, underwater scene simulation is still a difficulty since there is no module for it. Based on the analysis of Vega software and the research on seabed scene simulation methods, a Vega extending module named “Underwater Space” was created through developing module class and extending lynx interface. The module class was designed through developing DLL written in C . The Lynx was extended through developing keyword configure file, GUI configure file and lynx plug-in DLL. The problem that Vega can‘t simulate underwater space, is elementarily resolved. The results show that this module is efficient, easy using, and the seabed scene images am vivid. 相似文献
165.
通过对城轨交通信号系统设备招标偏离的分析,提出解决偏离的措施。强调要建立适合国情的信号系统工程与产品标准体系的重要意义。 相似文献
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For the applied limitation of the existing threshold decryption schemes based on the (t, n) structure, an identity-based threshold decryption scheme which can be applied on the access structure is proposed through
designing a special distribution algorithm of the private key shares. The generation and distribution of private key shares,
the encryption, the decryption and the combination are introduced in detail. The validity and security of the scheme are proved
and analyzed. Comparisons with the existing schemes show that the proposed scheme is more flexible. 相似文献
168.
Cluster tools have advantages of shorter cycle times, faster process development, and better yield for less contamination.
The sequence of dual-arm cluster tools is a complex logistics process during the semiconductor production. Efficient use of
cluster tools is naturally very significant to competitive fab operations. Generating an optimized sequence in a computationally
efficient manner and assessing the quality of the requirements to improve the fab production are the key factors for semiconductor
manufacturing productivity. The Petri net modeling is introduced to minimize the makespan of the process for the three different
logical modes and select a better mode after comparing the makespan among the three logical modes. The tool sequence optimization
problem is formulated as optimization firing transition sequences based on the Petri net and then the formulation is converted
to be linearly solved by the branch-and-cut method in the standard commercial solver CPLEX. Special methods for the linear
conversion are highlighted. Due to the limited calculation time requirement for the real production and the large scale of
the problem, special methods for the efficiency tuning are applied according to the characteristics of the problem. Numerical
testing is supported by one of the most advanced semiconductor enterprises and the computational results show significant
improvement compared with the traditional manual sequence results. 相似文献
169.
An enhancement-based Poisson denoising method for photon-limited images is presented. The noisy image is firstly pre-processed for enhancing incomplete object information, and then it is denoised while preserving the restored structural details. A variational regularization model based on Euler’s elastica (EE) is proposed for image enhancement pre-processing. A nonlocal total variation (NLTV) regularization model is then employed in the second stage of image denoising. The above two optimization problems are solved by the alternating direction method of multipliers (ADMM). For Poissonian images with low image peak values, experiments demonstrate the validity and efficiency of the proposed method for both restoring geometric structure and removing noise. 相似文献
170.
装配式公路钢桥在国防交通应急保障和平时抢险救灾中发挥着重要作用,但目前这类钢桥一直是人工拼装架设,存在主要构件既大又重、架桥的劳动强度大、速度慢、安全性差等问题。以现有的公路施工机械——50装载机为主要机械,研究了一套机械化辅助架设钢桥的器具,介绍了器具的主要结构和功能。采用此套器具,能够解决桥件的吊装、桥件的水平短途运输,以及桥架设好后整桥推运到位问题,减轻劳动强度,提高架桥速度。 相似文献