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91.
The aerodynamic and aeroacoustic performances of outdoor unit with two different types of grille have been investigated in present study. Experimental results indicate that the grille sharp will affect the flow rate and increase broadband noise level of outdoor unit. Based on noise generation mechanism and CFD simulation, vortex shedding noise model and inlet turbulence noise model are adopted to predict the broadband noise level of outdoor unit. When vortex shedding noise is concerned, the wake parameters should be calculated at 3 mm downstream of grille to achieve good accuracy. Inlet turbulence noise is generated from the interaction between blade wake and the grille, and plays less important role in present outdoor unit configuration. In comparison with experimental results, it is shown that the broadband noise prediction method could provide reasonable accuracy and the error between prediction and experiment is less than 1 dBA. 相似文献
92.
在物联网智能家居系统中,将按功能分立的抄表网、环境网、电控网、安防网等分立子网,融合成按信息流向的感知网、控制网。本文介绍了采用NXP Cortex-M3/M0系列ARM微处理器设计开发物联网智能家居系统的技术要点。 相似文献
93.
未来课堂是针对未来创新人才培养需求、以新课程改革为支撑,以互动为核心,以促进课堂主体和谐、自由发展的一种高效课堂。本文分析了未来课堂的必要性和特性的基础上,构建了基于云端的未来课堂理论模型,该模型对创新教育有一定的借鉴作用。 相似文献
94.
Fe2O3由于成本低廉,储量丰富和理论比容量高(1007 mA hg^-1)等特点,在锂离子电池负极材料的应用中极具发展前景.然而一些问题仍然存在,如:充放电过程中比容量的迅速衰减,不可逆的体积膨胀以及较短的循环寿命等.这些问题严重制约了Fe2O3在锂离子电池中的实际应用.为了突破这些局限,本文以金属-有机骨架(MOF... 相似文献
95.
The mechanical properties of hot rolled strip are the key index of product quality,and the soft sensing of them is an important decision basis for the control a... 相似文献
96.
Harmonic cavities (HCs) are widely used in electron storage rings, mainly to increase the Touschek lifetime by lengthening bunches. HCs have become critical com... 相似文献
97.
When the ice-going ships advance in the polar region,the navigation in the floe ice region is often encountered,the hull will suffer the high-frequency contact ... 相似文献
98.
Na Li Guangyi Liu Huimin Zhang Quan Zhao Yun Zhao Zhou Tong Yingying Wang Junshuai Sun 《中国通信》2022,(3):1-15
The convergence of information, communication, and data technologies(ICDT) has been identified as one of the developing trends of the sixth generation(6G) network. Service-based architecture(SBA) as one of the promising information technology, has been preliminarily introduced into the fifth generation(5G) core network(CN) and successfully commercialized, which verifies its feasibility and effectiveness. However, SBA mainly focuses on the control plane of CN at present and the SBA-CN user plane ... 相似文献
99.
Chronic kidney disease (CKD), as one of the main complications of many autoimmune diseases, is difficult to cure, which places a huge burden on patients’ health and the economy and poses a great threat to human health. At present, the mainstream view is that autoimmune diseases are a series of diseases and complications caused by immune cell dysfunction leading to the attack of an organism’s tissues by its immune cells. The kidney is the organ most seriously affected by autoimmune diseases as it has a very close relationship with immune cells. With the development of an in-depth understanding of cell metabolism in recent years, an increasing number of scientists have discovered the metabolic changes in immune cells in the process of disease development, and we have a clearer understanding of the characteristics of the metabolic changes in immune cells. This suggests that the regulation of immune cell metabolism provides a new direction for the treatment and prevention of kidney damage caused by autoimmune diseases. Macrophages are important immune cells and are a double-edged sword in the repair process of kidney injury. Although they can repair damaged kidney tissue, over-repair will also lead to the loss of renal structural reconstruction function. In this review, from the perspective of metabolism, the metabolic characteristics of macrophages in the process of renal injury induced by autoimmune diseases are described, and the metabolites that can regulate the function of macrophages are summarized. We believe that treating macrophage metabolism as a target can provide new ideas for the treatment of the renal injury caused by autoimmune diseases. 相似文献
100.