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101.
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Yuehui Ji Hailiang Zhou Qun Zong 《International Journal of Adaptive Control and Signal Processing》2019,33(5):829-842
An adaptive neural network (NN) command filtered backstepping control is proposed for the pure‐feedback system subjected to time‐varying output/stated constraints. By introducing a one‐to‐one nonlinear mapping, the obstacle caused by full stated constraints is conquered. The adaptive control law is constructed by command filtered backstepping technology and radial basis function NNs, where only one learning parameter needs to be updated online. The stability analysis via nonlinear small‐gain theorem shows that all the signals in closed‐loop system are semiglobal uniformly ultimately bounded. The simulation examples demonstrate the effectiveness of the proposed control scheme. 相似文献
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Zhou Wenhui Wu Jie Zhong Weifeng Zhang Haochuan Shu Lei Yu Rong 《Mobile Networks and Applications》2019,24(3):950-961
Mobile Networks and Applications - Energy trading mechanism for microgrids has an inherent two-layer architecture, in which the energy trading at the first layer is between a microgrid aggregator... 相似文献
105.
水平方向上的空气对流和复杂的地面状况会导致大气热辐射计算的不确定度增大,目标发射起始段的红外辐射特性测量有助于实现目标识别。因此,研究水平大气透过率和热辐射对目标的高精度红外辐射特性测量具有十分重要的意义。针对以上问题,首先借鉴垂直廓线理论建立了同层大气“水平温度廓线”模型,然后推导了水平方向计算大气透过率和热辐射的公式,并对其进行了实验验证。最后将MODTRAN软件计算和实验测量的大气热辐射结果进行了比较。实验结果表明,传统软件的热辐射计算精度为8.65% ,而本文方法的计算精度为4.91%。该实验说明,在水平方向上,这种算法是正确的。通过公式推导和实验验证说明了该方法的合理性,为水平方向大气透过率和热辐射的计算提供了一种新的思路。 相似文献
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Yifan Zhang Shaowei Bo Tao Feng Xialing Qin Yilin Wan Shanshan Jiang Chunxiao Li Jing Lin Tianfu Wang Xin Zhou Zhong‐Xing Jiang Peng Huang 《Advanced materials (Deerfield Beach, Fla.)》2019,31(21)
To design a clinically translatable nanomedicine for photodynamic theranostics, the ingredients should be carefully considered. A high content of nanocarriers may cause extra toxicity in metabolism, and multiple theranostic agents would complicate the preparation process. These issues would be of less concern if the nanocarrier itself has most of the theranostic functions. In this work, a poly(ethylene glycol)‐boron dipyrromethene amphiphile (PEG‐F54‐BODIPY) with 54 fluorine‐19 (19F) is synthesized and employed to emulsify perfluorohexane (PFH) into a theranostic nanoemulsion (PFH@PEG‐F54‐BODIPY). The as‐prepared PFH@PEG‐F54‐BODIPY can perform architecture‐dependent fluorescence/photoacoustic/19F magnetic resonance multimodal imaging, providing more information about the in vivo structure evolution of nanomedicine. Importantly, this nanoemulsion significantly enhances the therapeutic effect of BODIPY through both the high oxygen dissolving capability and less self‐quenching of BODIPY molecules. More interestingly, PFH@PEG‐F54‐BODIPY shows high level of tumor accumulation and long tumor retention time, allowing a repeated light irradiation after a single‐dose intravenous injection. The “all‐in‐one” photodynamic theranostic nanoemulsion has simple composition, remarkable theranostic efficacy, and novel treatment pattern, and thus presents an intriguing avenue to developing clinically translatable theranostic agents. 相似文献
108.
In order to comply with discharge standards, a gas–solid separator is used to remove solid particles from the thorium molten salt reactor-solid fuel(TMSR-SF)system. As a key component, it directly determines system energy efficiency. However, current gas–solid separators,based on activated carbon adsorption technology, result in high pressure drops and increased maintenance costs. In the present study, a new combined gas–solid separator was developed for the TMSR-SF. Based on a simplified computational fluid dynamics(CFD) model, the gas–solid twophase flow and the motion trajectory of solid particles were simulated for this new separator using commercial ANSYS 16.0 software. The flow and separation mechanism for this structure were also been discussed in terms of their velocity effects and pressure field distributions, and then the structure was optimized based on the influence of key structural parameters on pressure and separation efficiency. The results showed that the standard k–e model could be achieved and accurately simulated the new combined separator. In this new combined gas–solid separator, coarse particles are separated in the first stage using rotating centrifugal motion, and then fine particles are filtered in the second stage, giving a separation efficiency of up to 96.11%. The optimum blade inclination angle and numbers were calculated to be 45° and four, respectively. It implicated that the combined separator could be of great significance in a wide variety of applications. 相似文献
109.
非调质钢50MnSiV(/%:0. 50C,0.52S,1.20Mn,0.010P,0.025S,0.15Cr,0.10V,0.015Ti,0.015N)制造的新能源汽车电机轴,省去传统调质钢20CrMnTiH渗碳热处理和矫正精整工序,不仅可提高材料95%利用率和2天交货周期,还可以降低25%成本。50MnSiV钢抗拉强度1100 MPa、屈服强度858 MPa、冲击功48J。其静扭扭矩(4697 Nm)、疲劳寿命(±1600 Nm双向扭转12万次、±1400 Nm双向扭转27万次)较渗碳20CrMnTiH钢提高了27%和93%~140%,并且其性能指标和8万公里的路试结果均满足电机轴的技术要求。 相似文献
110.