Based on the introduction of the WiMAX standards, relevant technologies and applications, three essential factors for WiMAX networking are analyzed. They are the frequency plan, Authentication Authorization Accounting...Based on the introduction of the WiMAX standards, relevant technologies and applications, three essential factors for WiMAX networking are analyzed. They are the frequency plan, Authentication Authorization Accounting (AAA) and the mobility management. Networking solutions for the fixed and mobile applications are presented respectively. It is noted that the evolution of wireless WiMAX networking will go through four phases: the outdoor access phase, the indoor access phase, the seamed roaming phase and the seamless mobility phase. It is predicted that WiMAX will eventually converge with the NGN and the mobile cellular networks.展开更多
营养液膜栽培技术(Nutrient Film Technique,NFT)模式下,作物对环境变化更加敏感。为保障作物根区环境条件合理,需要精准调控栽培管道内的温度,从而有效提高水培生菜品质,同时降低整体温室环境调控能耗。采用遗传算法(Genetic Algorithm...营养液膜栽培技术(Nutrient Film Technique,NFT)模式下,作物对环境变化更加敏感。为保障作物根区环境条件合理,需要精准调控栽培管道内的温度,从而有效提高水培生菜品质,同时降低整体温室环境调控能耗。采用遗传算法(Genetic Algorithm,GA)优化BP神经网络模型的输入权重和阈值,以单个NFT栽培槽为研究对象,对槽内根区不同的监测区域分别构建温度预测模型,并与标准的BP神经网络和卷积神经网络(Convolutional Neural Network,CNN)模型进行对比。结果表明,GA-BP预测模型与标准BP和CNN神经网络模型相比,均方根误差分别降低0.82和0.42,平均绝对误差分别降低0.54和0.25,绝对系数分别提高0.08和0.03。该方法可提高基于BP神经网路算法对NFT根区温度预测模型精确度,为根区温度的精准控制提供可靠依据。展开更多
文摘Based on the introduction of the WiMAX standards, relevant technologies and applications, three essential factors for WiMAX networking are analyzed. They are the frequency plan, Authentication Authorization Accounting (AAA) and the mobility management. Networking solutions for the fixed and mobile applications are presented respectively. It is noted that the evolution of wireless WiMAX networking will go through four phases: the outdoor access phase, the indoor access phase, the seamed roaming phase and the seamless mobility phase. It is predicted that WiMAX will eventually converge with the NGN and the mobile cellular networks.