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71.
文章简要介绍了DCS系统结构及本系统中现场控制站的组成,重点阐述了该系统中网络通信任务的设计和实现过程,并给出了主要的程序代码。实测表明,程序运行稳定可靠,系统性能达到了设计要求。 相似文献
72.
超高速水下航行器在水下航行时,表面大部分被超空泡所包覆,其运动特性发生显著变化,使得其工况变得更为复杂、控制难度加大;通过分析它的运动特点,建立了系统模型方程,并提出把空化器作为控制面,通过操纵其舵角改变量来控制航行器航向;最后运用PI极限舵控制算法进行仿真分析,结果表明此控制方法简单易实现,产生的偏差小,同时还提高了系统的响应速度,较好地满足了系统要求,分析结论可为超高速水下航行器控制系统设计提供参考。 相似文献
73.
74.
Haibin Duan Senqi Liu Daobo Wang Xiufen Yu 《Simulation Modelling Practice and Theory》2009,17(6):1160-1169
Three degree-of-freedom (3-DOF) high precision flight simulator is a type of key hardware-in-loop equipment in the fields of aeronautics and astronautics. The conventional Proportional–Integral–Derivative (PID) is a widely used industrial controller that uses a combination of proportional, integral and derivative action on the control error to form the output of the controller. It is well known that the undesired phenomena caused by friction can lead to overall flight simulator performance degradation or instability. This paper presents a novel kind of hybrid Ant Colony Optimization (ACO)-based PID and LuGre friction compensation controller for 3-DOF high precision flight simulator. On the basis of introduction of the basic principles of ACO, the controlling scheme design for the 3-DOF high precision flight simulator is presented. Based on the popular LuGre friction model, a novel nonlinear friction compensation controller for 3-DOF high precision flight simulator is also developed. The proposed Lyapunov function proves the robust global convergence of the tracking error. The parameters tuning of PID can be summed up as the typical continual spatial optimization problem, grid-based searching strategy is adopted in the improved ACO algorithm, and self-adaptive control strategy for the pheromone decay parameter is also adopted. Modularization design is adopted in the 3-DOF high precision flight simulator. This software can process the position and status signals, and display them on the friendly interface. Double buffer mechanism is adopted in the communication protocol between lower Industrial Personal Computer (IPC) and upper IPC. The series experimental results have verified the feasibility and effectiveness of the proposed hybrid ACO-based PID and LuGre friction compensation controller. 相似文献
75.
现今的产品设计材料教学,很大程度上仅仅局限在对材料本身的讲授,而没有把材料置于设计中,将材料的设计表现意义传达出来,这种对材料片面性的理解势必影响学生在设计中对材料的充分使用。本文就以茶具为例,透过茶具材质的发展来探讨材料对于设计的深层意义,并且提出在产品设计的材料教学中,应该在设计的大前提之下对材料知识进行全面的讲授与科学的分析。 相似文献
76.
数码相机定位是计算机图形学中的一个重要课题,在图像处理等方面有着广泛的应用,对数码相机进行合理建模分析,并利用双目视觉原理对图像进行标定,最后例证了此方法的有效性和精确性。 相似文献
77.
《考工记》是一部先秦古著。著者佚名,有说非一人一时之作,成书年代大约在春秋战国之际,到汉代后人将其编入《周礼》,故又称《周礼考工记》。作为先秦百工技艺之书,它反映了当时工艺技术和设计发展水平,书中记载的"物尽其用"、"因材施艺"、"以人为本"、"天人合一"的造物法则体现了中国传统文化对设计的影响。本文通过在功能、材料、人文、以及象征意义等方面的具体分析,来揭示传统造物之美。 相似文献
78.
Duan Bin Yanyan Du Beibei Yang Hongbin Lu Yao Liu Yongyao Xia 《Advanced functional materials》2023,33(8):2211765
Aqueous rechargeable zinc batteries (ARZBs) are recently prevailing devices that utilize the abundant Zn resources and the merits of aqueous electrolytes to become a competitive alternative for large-scale energy storage. Benefiting from the unique inductive effect and flexible structure, the past five years have experienced a diversiform of phosphate-based polyanion materials that are used as cathodes in ARZBs. In this review, the most recent advances in the Zn2+ storage mechanisms and electrolyte optimization of the phosphate-based cathodes of ARZBs, which mainly focus on vanadium/iron-based phosphates and their derivatives are presented. Furthermore, in addition to significant progress on polyanion phosphate-based cathode materials, the design strategies both for electrode materials and compatible electrolytes are also elaborated to improve the energy density and extend the cycling life of aqueous Zn/polyanion batteries. 相似文献
79.
Jiayang Liao Xiang Lv Xi-xi Sun Junhua Li Haomin Wang Qiang Chen Hanpeng Lu Duan Wang Jian Bi Jiagang Wu 《Advanced functional materials》2023,33(34):2303637
Although the piezo-catalysis is promising for the environmental remediation and biomedicine, the piezo-catalytic properties of various piezoelectric materials are limited by low carrier concentrations and mobility, and rapid electron-hole pair recombination, and reported regulating strategies are quite complex and difficult. Herein, a new and simple strategy, integrating phase boundary engineering and defect engineering, to boost the piezo-catalytic activity of potassium sodium niobate ((K, Na)NbO3, KNN) based materials is innovatively proposed. Tur strategy is validated by exampling 0.96(K0.48Na0.52)Nb0.955Sb0.045O3-0.04(BixNa4-3x)0.5ZrO3-0.3%Fe2O3 material having phase boundary engineering and conducted the defect engineering via the high-energy sand-grinding. A high reaction rate constant k of 92.49 × 10−3 min−1 in the sand-grinding sample is obtained, which is 2.40 times than that of non-sand-grinding one and superior to those of other representative lead-free perovskite piezoelectric materials. Meanwhile, the sand-grinding sample has remarkable bactericidal properties against Escherichia coli and Staphylococcus aureus. Superior piezo-catalytic activities originate from the enhanced electron-hole pair separation and the increased carrier concentration. This study provides a novel method for improving the piezo-catalytic activities of lead-free piezoelectric materials and holds great promise for harnessing natural energy and disease treatment. 相似文献
80.
Zhe Zhang Zhixiang Li Peiran Wang Hongbin Chen Kangqiao Ma Yunxin Zhang Tainan Duan Chenxi Li Zhaoyang Yao Bin Kan Xiangjian Wan Yongsheng Chen 《Advanced functional materials》2023,33(22):2214248
Developing new polymerized small molecular acceptor (PSMA) is pivotal for improving the performance of all-polymer solar cells. On the basis of this newly developed CH-series small molecule acceptors, two PSMAs are reported herein (namely PZC16 and PZC17, respectively). To reduce the molecular torsion caused by the traditional aromatic π-bridges, non-aromatic conjugated units (ethynyl for PZC16 and vinylene for PZC17) are adopted as the linkers and their effect on the photo-physical properties as well as the device performance are systematically investigated. Both polymer acceptors exhibit co-planar molecular conformation, along with broad absorption ranges and suitable energy levels. In comparison with the PM6:PZC16 film, the PM6:PZC17 film exhibits more uniform phase separation in morphology with a distinct bi-continuous network and better crystallinity. The PM6:PZC17-binary-based devices exhibit a satisfactory PCE of 16.33%, significantly higher than 9.22% of the PZC16-based devices. Impressively, PM6:PZC17-based large area device (ca. 1 cm2) achieves an excellent PCE of 15.14%, which is among the top performance for reported all-polymer solar cells (all-PSCs). 相似文献