The time series of IGS stations in China are studied using spectrum analysis and wavelet analysis,and their periodic variation characteristics are shown.
利用谱方法和小波技术分析了我国IGS站坐标时间序列,阐述了其周期变化特征,即绝大部分台站在N、E、U方向都具有半年周期性、年周期性,U方向周期特性相对明显,同时台站的主要周期成分和时频局部特性又具有一定区域性。
Finding that there exists periodic variation about diurnal solar time and semi-diurnal solar time in rate of the cosmic ray.
利用小波变换,结合折叠周期分析方法,对羊八井宇宙线观测站Tibet II/HD阵列1997年11月到1998年6月的实验记录数据进行了周期分析,发现1TeV～10TeV宇宙线流强中存在着太阳日和半太阳日的周期变化。
From the morphology of the spiral jet, it is found that there is a periodic variation in the structure of the jet, with a period of about 8-9 days.
通过对上海天文台佘山观测基地１９９７年３月至５月初期间所得到的Ｈａｌｅ－Ｂｏｐｐ彗 星喷流观测资料的处理和分析，发现该彗星的喷流结构有周期性变化，其周期为８—９ 天，这种周期变化可能与彗星的自转轴在空间的进动周期有关。
On the basis of measured mud fluid data in the Northern Channel of Changjiang Estuary in China,the periodical changes of mud fluid are discussed.
根据2000年长江口北槽浮泥的实测资料,分析浮泥厚度和体积等几何尺度随时间的变化,发现长江口北槽浮泥存在日、半月和年际三种周期变化;日周期的变化受潮流动力周期的控制,这是由潮流冲刷浮泥形成的悬沙并再絮凝沉积造成的;半月周期的变化受潮流半月周期变化引起的泥沙供给量的变化控制;年周期的变化主要是由影响细颗粒泥沙絮凝沉积的长江口水温的年度变化所控制,泥沙供给和动力的年周期变化也有一定的影响。
The possible influences of El Nio events on precipitation of Henan are discussed by comparing the period variation of SST cold or warm structures with dry or wet changes of Henan precipitation.
本文采用小波变换方法分析了近 5 0年来赤道东太平洋月海温距平序列和河南省月降水量距平序列的多层次时间尺度结构 ,对厄尔尼诺事件和河南降水的周期变化规律进行了对比分析 ,并讨论了厄尔尼诺对河南降水的可能影响。
The results show that the similar periodical change of mould friction force was observed in two kinds of oscillation modes in steady casting;positions of maximum and minimum mould friction force during a cycle were some what regular;mould friction force kept being positive for a long time and fluctuated strongly at start of casting.
研究结果表明:在稳定拉坯阶段,结晶器摩擦力在两种振动模式下具有相似的周期变化过程;周期内摩擦力最值的出现位置呈现出一定的规律性和不确定性;开浇阶段摩擦力会在长时间内维持正值且波动剧烈。
This is the cycle of economic booms and slumps.
这是经济繁荣和经济萧条的周期变化。
the cycle of economic booms and slumps
经济繁荣和经济萧条的周期变化.
Causes of the Short-Period Water Level Fluctuation of Well 10-1 of Shanxi
晋10—1井水位短周期变化的原因
An Empirical Study on the Related Factors of Cyclical Changes in the Securities Market
证券市场周期变化相关因素实证分析
Study on Year-cycle of Soil Factors from the Chlorosis of Camphor Tree
樟树黄化土壤因子年周期变化规律的研究
The lowest frequency of a periodically varying quantity or of a vibrating system.
基频周期变化量或振动系统的最低频率
A Study on the Seasonal Changes of Mineral Nutrient Contents in the Leaves of Chinese Jujube (Zizyphus jujuba Mill.)
枣叶片营养元素含量年周期变化的研究
PERIODIC VARIATION AND LINEAR RISE TREND OF MONTHLY MEAN VALUE OF SEA-LEVEL IN PACIFIC OCEAN
太平洋月平均水位周期变化和线性升降趋势
LES TERMES P(?)RIODIQUES DE LA VARIATION DE LATITUDE DE 1935.0-1941.0
1935.0—1941.0年?度变化的周期?
Research for Rapid Variability, Periodic Variability and Evolution of Blazars;
Blazars的快速光变、周期光变与演化研究
A sudden change in the period of rotation of a neutron star.
中子星旋转周期的突然变化
breathing of microphone
炭粒传声器中的短周期电阻变化
breathing of transmitter
送话器电阻的周期性小变化
CIRCADIAN CYCLE OF URINARY CORTISOL CONCENTRATION IN THE GIANT PANDA (AILUROPODA MELANOLEUCA)
大熊猫尿中皮质醇含量变化的日周期
Frequency Conversion Based on Periodically Poled Lithium Niobate Waveguide;
周期极化铌酸锂波导的频率变换研究
Study on Cost Optimization of Transmission and Distribution Equipment Life Cycle;
输变电设备全寿命周期成本优化研究
Changes of Cyclin D1 Expression Following Human Brain Contusion;
人脑挫伤后细胞周期素D1表达的变化
The Life-cycle for Construction Project Value and Economic Growth to Construction Industry inChina;
建筑业产业定位与工程价值变化周期