基于多模型模糊神经网络的智能天气预报

【作者】 周岩；

【导师】 孙慰迟； 赖来利；

【作者基本信息】 复旦大学 ， 计算机应用技术， 2007， 硕士

【摘要】 上个世纪90年代以来,国内外学者在开展了神经网络天气预报建模和气候分析等应用研究。然而随着神经网络方法在气象科学领域研究的不断深入,研究人员发现神经网络方法在天气预报的应用中存在一个重要的问题,即在利用神经网络方法进行气象预报建模时,神经网络的初始权值、网络结构以及网络的学习参数,动量因子都是难以确定的,往往要通过反复训练来确定网络的结构和各种参数,这样会导致在应用中出现过拟合问题,严重影响网络的泛化能力,很大程度上限制神经网络在实际天气业务中的应用。该问题的研究不仅关系到在大气学科中能否进一步深入开展有关人工神经网络方法的业务预报应用,并且也是目前人工神经网络应用理论研究中尚未得到很好解决的关键技术问题。随着神经网络技术的发展,神经网络集成、遗传神经网络、模糊神经网络等新技术的兴起,我们有了寻找其他解决方法的途径,可以就神经网络技术在天气预报领域的应用进行一些新的尝试。本文以上海地区气象预报作实验,结合了本地区的天气特点,吸取了上海中心气象台多位首席预报员的预报知识,建立了基于自适应模糊神经网络(ANFIS)的预报模型。为了验证自适应模糊神经网络(ANFIS)在智能天气预报中的优越性和实用性,本文亦用一般BP神经网络对实测数据进行训练,建立预报模型,得到预报结果。本文用ANFIS模糊神经网络和一般的BP神经网络得到预测结果与实测结果进行比较,对模型的有效性进行评价。通过实例验证,ANFIS模糊神经网络在智能天气预报方面具有一定的应用价值。更多还原

【Abstract】 Since the 90’s of 20 centuries, Some the Neural Network forecast modles were applied in domestic and international atmosphere course. With the research be made a thorough and careful, the researcher discovered an important problem in the actual weather forecast application, which the Neural Network beginning connection weights, the network construction, learning factor and momentum factor were hard to certain. Because the researcher need train many times so that all kinds of parameters can be definite, the Neural Network become over-fitting and the serious influence the Neural Network generation ability. This problem will limit the Neural Network in the actual forecast application. The research of that problem not only relate to whether to can go deep into the Neural Network business forecast research in atmosphere course but also is the key technique in the theories research.We can try again since the theory of ANN like Genetic ANN, ANN ensemble, and Fuzzy ANN is developed. Considering the characteristic of weather of Shanghai and learning abundant meteorology knowledge from the experts of Shanghai weather bureau, we train our ANFIS (Adaptive Network-based Fuzzy Inference System) to do weather forecasting in Shanghai, and compare the forecasting results to the BP Neural Networks forecasting results. The comparative results make we validate that the ANFIS has much more advantage.更多还原