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71.
以某混凝土重力坝非溢流坝段动力特性为背景,探讨流固耦合效应对结构自振特性的影响,运用大型有限元软件对结构自振特性进行分析计算,得出了流体对结构自振特性影响以及结构的固有频率,避免在运行过程中发生共振,造成对结构的破坏。 相似文献
72.
In this paper, robust adaptive control is developed for a thruster assisted position mooring system in the transverse direction. To provide an accurate and concise representation for the dynamic behavior of the mooring system, the flexible mooring lines are modeled as a distributed parameter system of partial differential equations (PDEs). The proposed control is applied at the top boundary of the mooring lines for station keeping via Lyapunov’s direct method. Adaptive control is designed to handle the system parametric uncertainties. With the proposed robust adaptive control, uniform boundedness of the system under the ocean current disturbance is achieved. The proposed control is implementable with actual instrumentations since all the signals in the control can be measured by sensors or calculated by using a backward difference algorithm. The effectiveness of the proposed control is verified by numerical simulations. 相似文献
73.
Poly(5‐bromoindole) (PBrI) films were synthesized electrochemically by direct oxidation of 5‐bromoindole in pure boron trifluoride diethyl etherate. The oxidation potential of 5‐bromoindole in this medium was measured to be only 0.97 V vs. saturated calomel electrode, which was lower than that determined in acetonitrile + 0.1 mol L?1 Bu4NBF4 (1.08 V). PBrI films obtained from this medium showed good electrochemical behavior and good thermal stability. Structural studies showed that the polymerization of 5‐bromoindole ring occurred at 2,3 position. As‐formed PBrI films were thoroughly soluble in strong polar solvent dimethylsulfoxide and partly soluble in tetrahydrofuran. Fluorescent spectral studies indicated that PBrI was a good blue‐light emitter. The excitation and emission spectra of PBrI showed a significant shift to longer wavelength compared with that of the monomer, consistent with the greater extent of electron delocalization. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 539–547, 2006 相似文献
74.
In this paper we introduce VideoGraph, a novel non-linear representation for scene structure of a video. Unlike classical linear sequential organization, VideoGraph concentrates the video content across the time line by structuring scenes and materializes with two-dimensional graph, which enables non-linear exploration on the scenes and their transitions. To construct VideoGraph, we adopt a sub-shot induced method to evaluate the spatio-temporal similarity between shot segments of video. Then, scene structure is derived by grouping similar shots and identifying the valid transitions between scenes. The final stage is to represent the scene structure using a graph with respect to scene transition topology. Our VideoGraph can provide a condensed representation in the scene level and facilitate a non-linear manner to browse videos. Experimental results are presented to demonstrate the effectiveness and efficiency by using VideoGraph to explore and access the video content. 相似文献
75.
以氮气和水为实验体系,采用均质混合模型,研究微混合器的微通道中两相流通过微通道的压降,并测定了两相流的传质系数.结果表明,微通道当量直径为95.2 μm,气体速率为1.089~4.355 m/s,液体速率为0.006 41~0.170 90 m/s的条件下,均质混合模型计算压降值与实测值吻合良好.气速为1.633~3.484 m/s,液速为0.025 6 m/s时,随着气速增加,传质系数呈递增的趋势.气速为1.633~3.484 m/s,液速为0.019 2 m/s时,随着气速增加,传质系数先增加后降低然后再增加.传质系数对液速变化更为敏感. 相似文献
76.
77.
This paper presents a robotic head for social robots to attend to scene saliency with bio-inspired saccadic behaviors. Scene saliency is determined by measuring low-level static scene information, motion, and object prior knowledge. Towards the extracted saliency spots, the designed robotic head is able to turn gazes in a saccadic manner while obeying eye–head coordination laws with the proposed control scheme. The results of the simulation study and actual applications show the effectiveness of the proposed method in discovering of scene saliency and human-like head motion. The proposed techniques could possibly be applied to social robots to improve social sense and user experience in human–robot interaction. 相似文献
78.
Chenping Hou Feiping Nie Hua Wang Dongyun Yi Changshui Zhang 《Neural computing & applications》2014,24(7-8):1555-1568
The recent years have witnessed a surge of interests of learning high-dimensional correspondence, which is important for both machine learning and neural computation community. Manifold learning–based researches have been considered as one of the most promising directions. In this paper, by analyzing traditional methods, we summarized a new framework for high-dimensional correspondence learning. Within this framework, we also presented a new approach, Local Approximation Maximum Variance Unfolding. Compared with other machine learning–based methods, it could achieve higher accuracy. Besides, we also introduce how to use the proposed framework and methods in a concrete application, cross-system personalization (CSP). Promising experimental results on image alignment and CSP applications are proposed for demonstration. 相似文献
79.
国产耐火砖在德士古水煤浆气化炉的使用 总被引:2,自引:0,他引:2
分析气化炉耐火材料损蚀原因及国产耐火砖在德士古水煤浆加压气化炉中的使用情况,使用结果证明,国产耐火砖可以替代进口砖,每年节约设备投资600万元左右。 相似文献
80.