对增长趋势季节数列测定季节变动方法的一点看法

文章通过对移动平均法和趋势方程拟合法测定增长趋势季节数列的季节变动进行比较，肯定了移动平均法测定季节变动是更好的方法。

豆粕需求呈季节性增长

国内豆粕需求继续呈现季节性恢复增长，近期国内豆粕现货市场价格继续趋于上扬。9月初．全国豆粕平均价格较前期上涨50元／吨．而个别地区价格涨幅甚至超过百元，其中大连地区豆粕价格整体在2750-2800元／吨之间，华北山东地区油厂报价基本都在2850元／吨以上，华东地区豆粕报价最高也达到2850元／吨，华南地区油厂报价也均在2850-2880元／吨之间。价格的上扬一定程度上刺激了市场需求的增长，我们认为国内豆粕需求将呈现季节性的恢复增长，具体分析如下。

Estimate of CH_4 Emissions from Year-Round Flooded Rice Fields During Rice Growing Season in China

A special kind of rice field exists in China that is flooded year-round. These rice fields have substantially large CH4emissions during the rice-growing season and emit CH4 continuously in the non-rice growing season. CH4 emission factors were used to estimate the CH4 emissions from year-round flooded rice fields during the rice-growing season in China.The CH4 emissions for the year-round flooded rice fields in China for the rice growing season over a total area of 2.66Mha were estimated to be 2.44 Tg CH4 year-1. The uncertainties of these estimations are discussed as well. However,the emissions during the non-rice growing season could not be estimated because of limited available data. Nevertheless,methane emissions from rice fields that were flooded year-round could be several times higher than those from the rice fields drained in the non-rice-growing season. Thus, the classification of 'continuously flooded rice fields' in the IPCC(International Panel on Climate Change) Guidelines for National Greenhouse Gas Inventories is suggested to be revised and divided into 'continuously flooded rice fields during the rice growing season' and 'year-round flooded rice fields'.

季节型增长趋势电力消费预测研究:基于中国的实证分析

以我国月电力消费量为例,研究了季节型增长趋势中长期电力指标的预测问题。提出采用离散小波变换对季节型增长趋势历史数据进行分解并对各频率分解系数分别进行重构,在剔除随机性波动后,将长期增长趋势及各规律性波动趋势通过RBF网络进行趋势外推预测,进而通过对不同趋势预测结果进行组合得到电力消费量的预测值。实证分析表明,经过离散小波分解处理后,RBF网络样本的规律性得到增强,其在有效模拟非线性变化规律的同时,泛化能力得以提高,因而具有较好的预测精度。