The reasons of this study consist of the diverse surgical effect , inadequate understanding of operation effect consistency , the possibility of disease progression , and only a few articles reported for long - term evaluation after uppp 由于此种手术的效果各家报告不一,对于手术效果恒定性以及疾病本身的长期变化也尚不甚了解,此外,关于此种手术后之长期评估的文献报告也比较少,因此我们认为有做此评估研究的必要。
The calculating result with the case of beijing - shanghai hspgs line shows that the traffic demand of hspgs line would follow the tendency - - - - - - at first increases in accordance with the economical growth , then the increasing rate slows down because of higher requirement of passenger to travel quality , eventually even may decrease because more passenger shift to plane 以京沪线为例进行的计算表明,高速铁路客运需求的长期变化规律是:首先因经济发展规模的增长而增加,后因旅客对服务质量的要求发生变化,市场份额降低,客运需求增速减缓甚至下降。
Then the paper investigated the regularity of different oil indices using time series statistical analysis method , which suggested that there are some regular components in it , including long - term secular trend , seasonal component and long - term cyclical component . the irregular component also plays an important part in it , mainly including the policy of opec , war , all kinds of international convention for the prevention of pollution from tankers and so on . and then a study of simulation and forecasting performance of arima time series model was conducted to crude oil indices , evidence shows that arima model performs better , especially for short - term forecasting 在此基础上,本文以时间序列分析作为基础研究手段,以德国海运费率指数公布的1980年1月至1999年12月的四类油运费率指数为研究对象,分析了四类油运费率指数的长期变化趋势、季节变化规律、长期周期循环变化规律和不规则变化规律,并应用arima时间序列模型对160000dwt以上的原油运费率指数进行了短期预测,取得了较好的预测效果。
Of course , the next big step for chinese space astronomy would be to deploy a satellite dedicated only for astronomical research . there are currently a few projects in the planning stage , including a hard x - ray all - sky survey satellite the hard x - ray modulation telescope mission , and a " microsatellite " weight less than 100 kg mission to study long - term variability of stars and galaxies space - based multi - band variable objects monitor 当然,下一步首先应是发射专门用作天文研究的卫星,目前有几个计划正处于策划阶段,包括建造一枚作硬x射线巡天观测的卫星硬x射线调制望远镜, hxmt和一枚微型卫星重量不逾100公斤,来研究恒星和星系的长期变化空间变源监视器, svom 。
Then the long time change feature of radiation climate over china is analyzed - the results show that , the radiation climate changes a little before 1950s . from 1950s to 1970s it is increasing , and it reached the apex in the 1970s . later it began to decline , up to the present 通过总辐射年值的10年滑动平均曲线和累积距平曲线可以得到我国太阳总辐射气候长期变化的趋势特征是: 50年代以前,我国的总辐射比较平稳,没有大的变化;在50年代前后,总辐射开始呈现增长的趋势;在整个的70年代,总辐射达到最高; 70年代末80年代初的时候,总辐射又开始了下降的趋势。