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41.
催化裂化装置龟甲网双层衬里的改进 总被引:1,自引:1,他引:0
顾一天 《石油化工设备技术》1995,16(2):25-28
通过对催化裂化装置老的龟甲网双层社里使用情况的调查研究以及对存在问题的分析,提出了改进措施。经近几年的实际应用考核证明,改进措施是行之有效的。在此基础上制订了院标“BL型隔热耐磨衬里施工技术要求”。 相似文献
42.
《Displays》2023
Road segmentation plays an important role in navigation systems and autonomous driving. However, many methods in road segmentation are based on supervised learning and suffer from performance degradation in the real world. There is a certain domain gap (distribution shift problem) between the source domain (training data) and the target domain (testing data). In this paper, we propose a Dual-Geometric Perception (DGP) approach for cross-domain road segmentation, which jointly uses semantic and dual-geometric information to learn the domain-invariant feature for road segmentation. First, we propose an RGB-N dual stream network structure, which effectively fuses normal vector information and RGB information to reduce domain gap. Moreover, a dual geometric adversarial learning strategy is proposed to utilize depth-aware and normal vector features to perform better domain alignment. Furthermore, a self-training learning strategy is used to further improve the model’s generalizability in the target domain. Extensive experiments demonstrate that our proposed DGP achieves superior performance on lane-to-lane and lane-to-sidewalk road domain adaptation tasks. 相似文献
43.
双通道旋转变压器的解码问题一直是伺服控制闭环系统非常重要的一个问题,快速、准确的解码出伺服系统位置信息是闭环控制系统的关键。通过对某伺服系统闭环控制系统位置解码技术的研究,分析了RD26的解码过程及原理,设计一种基于RD26的双通道旋转变压器位置解码设备,此设备将双通道旋转变压器输出的信号与RD26相连,通过并口向FPGA发送数据,FPGA通过时序读取RD26信号,能将双通道旋转变压器粗机、精机的模拟电压信号转换成具有绝对位置的数字信号,不需要再进行纠错与粗精结合,解码精度可达到±2角分+1LSB。 相似文献
44.
Frequency regularization of a linked wind–diesel system using dual structure fuzzy with ultra-capacitor 下载免费PDF全文
Microgrids (μ-grids) are gaining increased interest around the world for supplying cheap and clean energy. In this paper, a μ-grid comprising a wind turbine generator (WTG) and diesel generator (DG) is considered. It is one of most practical and demanding systems suitable for the present energy crisis in isolated or rural areas. However, wind energy is intermittent in nature while load demand changes frequently. Therefore, a µ-grid can experience large frequency and power fluctuations. The speed governor of the DG tries to minimize the frequency and power deviations in µ-grid though its operation is slow and cannot adequately minimize system deviations. The paper proposes a novel arrangement based on a dual structured fuzzy (DSF) whose structure changes according to the switching limit with a reduced rule base. It has the capability to switch between proportional and integral actions and hence improves the frequency regularization of the μ-grid. The proposed strategy is tested in a μ-grid and the results considering step load alteration, load alteration at different instants of time, nonstop changing load request are compared with some of the well published methods to validate the effectiveness and simplicity of the present design. In addition, it shows that ultra-capacitor establishment in a μ-grid has a positive impact in minimizing system deviations with DSF for the studied cases. 相似文献
45.
针对常规的智能车传感器固定,视觉范围小,影响智能车的运行速度和准确性问题,提出了基于双舵机的大视觉智能巡线车控制系统。采用激光传感器、将路径识别传感器安装在车架上随动舵机的轮盘上,MCU通过控制随动摆头舵机来带动传感器的运动,使智能车的路径识别角度范围增大。经试验证明,此控制系统紧密结合双舵机的特点,充分发挥装在车架上的随动舵机带动路径识别传感器的优势,增大了智能车巡线过程中能识别到的路径范围,使智能车模实现高速稳定行驶。在不"丢线"的情况下,速度得到较大的提升,能适应各种赛道。 相似文献
46.
针对目前实时Linux的发展现状,对采用双内核方案的实时Linux系统——RTAI进行了研究,以便对RTAI进一步推广。首先对介于RTAI/Linux与硬件之间的资源虚拟层操作系统自适应域环境ADEOS(Adaptive Domain Environment for Operating Systerns)进行了剖析,主要包括ADEOS的体系结构,如何在域间传递事件(特别是中断),域在管线中是如何排列的,域是如何处理中断的。然后简略探讨了基于ADEOS的RTAI/Linux的具体实现,最后在系统重负载的情况下测试了标准Linux和基于LXRT模块的RTAI的实时任务响应时间。不仅验证了RTAI的硬实时性,还给出了基于LXRT模块编写RTAI实时应用程序的一般步骤。 相似文献
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49.
Haijun Zhang Author Vitae Author Vitae M.K.M. Rahman Author Vitae 《Pattern recognition》2009,42(11):2950-2719
A new dual wing harmonium model that integrates term frequency features and term connection features into a low dimensional semantic space without increase of computation load is proposed for the application of document retrieval. Terms and vectorized graph connectionists are extracted from the graph representation of document by employing weighted feature extraction method. We then develop a new dual wing harmonium model projecting these multiple features into low dimensional latent topics with different probability distributions assumption. Contrastive divergence algorithm is used for efficient learning and inference. We perform extensive experimental verification, and the comparative results suggest that the proposed method is accurate and computationally efficient for document retrieval. 相似文献
50.
Performance Analysis of The Auxiliary‐Model‐Based Multi‐Innovation Stochastic Newton Recursive Algorithm for Dual‐Rate Systems 下载免费PDF全文
The stochastic Newton recursive algorithm is studied for dual‐rate system identification. Owing to a lack of intersample measurements, the single‐rate model cannot be identified directly. The auxiliary model technique is adopted to provide the intersample estimations to guarantee the recursion process continues. Intersample estimations have a great influence on the convergence of parameter estimations, and one‐step innovation may lead to a large fluctuation or even divergence during the recursion. In the meantime, the sample covariance matrix may appear singular. The recursive process would cease for these reasons. In order to guarantee the recursion process and to also improve estimation accuracy, multi‐innovation is utilized for correcting the parameter estimations. Combining the auxiliary model and multi‐innovation theory, the auxiliary‐model‐based multi‐innovation stochastic Newton recursive algorithm is proposed for time‐invariant dual‐rate systems. The consistency of this algorithm is analyzed in detail. The final simulations confirm the effectiveness of the proposed algorithm. 相似文献