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为了充分利用无线网络资源,提升无线网络质量,充分利用了DBSCAN(Density Based Spatial Clustering of Applications with Noise)算法的优点,提出基于划分DBSCAN算法的话务量异常小区的检测方法,并通过对现网大量话务数据的统计分析,找出小区载频配置数和最佳话务量之间的关系。对话务量异常、拥塞率高的小区进行载频配置优化,并对城市小区网络优化有一定的指导意义。 相似文献
65.
贵阳黔中化工厂是一家高浓度烤烟专用复混肥生产定点厂家,从1993年投产以来,高浓度复混肥生产以蒸汽造粒为主。2004年12月,贵阳市政府取缔2 t以下燃煤锅炉,黔中厂决定安装热水造粒装置,通过3个不同配方的生产,热水造粒装置基本满足高浓度复混肥生产的要求。 相似文献
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The surfaces of carbon-carbon (C/C) aircraft brakes are usually coated with anti-oxidant to protect them from oxidation. These
surfaces do not include the friction surfaces since it is known that when anti-oxidant get onto the friction surface, the
friction coefficient decreases. The anti-oxidant migration (AOM), however, happens during processing, heat treatment and application.
In this study, phosphorus based anti-oxidants inhibited 3-D C/C aircraft brake system was investigated. The effects of their
migration on friction and wear in the 3-D C/C brakes were revealed by sub-scale dynamometer tests and microscopic analysis.
Dynamometer results showed that when AOM occurred, both landing and taxi coefficients decreased in humid environment and the
wear was slightly lowered. Microscopic study showed that under high humidity conditions there was no formation of the friction
film. 相似文献
68.
Le Zhang Zhichen Wang Lei Wang Zhe Zhang Xu Chen Lin Meng 《Digital Communications & Networks》2021,(4):551-558
Many large-scale and complex structural components are applied in the aeronautics and automobile industries.However,the repeated alternating or cyclic loads in ... 相似文献
69.
Yateng Wang Jianru Fan Hao Zhao Xiaoming Song Zhe Ji Congxia Xie Fushan Chen Yao Meng 《International journal of molecular sciences》2022,23(10)
The starch composite films (SCFs) will be one of the best alternative packaging materials to petroleum based plastic films, which mitigates white pollution and energy consumption. However, weak mechanical stability, water resistance, and dyeability has hindered the application of SCFs. Herein, a bioinspired robust SCFs with super-hydrophobicity and excellent structural colors were prepared by fiber-reinforcement and assembling SiO2/Polydimethylsiloxane (PDMS) amorphous arrays on the surface of SCFs. The properties of the designed SCFs were investigated by various methods including scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermo-gravimetric analysis (TGA), a tensile test, contact angle (CA) test, and an optical test. The results showed that the obtained SCFs possessed a higher tensile strength (55.17 MPa) attributed to the formed abundant hydrogen bonds between the molecular chains of the starch, cellulose fiber, and polyvinyl alcohol. Benefiting from the nanostructure with rough surface which were modified by materials with low surface free energy, the contact angle and sliding angle of the film reached up to 154° and 2°, respectively. The colors which were produced by the constructive interference of the coherent scattered light could cover all of the visible regions by tuning the diameters of the SiO2 nanoparticles. The strategy in the present study not only reinforces the mechanical strength and water resistance of SCFs but also provides an environmentally friendly way to color the them, which shows unprecedented application potential in packaging materials of the starch composite films. 相似文献
70.
氨氮废水的处理技术及发展 总被引:6,自引:0,他引:6
综述了当前氨氮废水处理技术的原理和各自的优缺点, 介绍了国内外氨氮废水处理的研究现状, 同时对氨氮废水处理前景进行了展望, 并提出了今后应着重考虑的几个问题。 相似文献