小波网络方法用于时间序列分析中非线性模型的研究   总被引：1，自引：0，他引：1  

秦伟良  金龙 《南京气象学院学报》1997,20(3):370-374

把小波网络方法用于时间序列分析中非线性模型，利用小波网络的非线性逼近能力，构造一个非线性函数，并对温度资料进行处理，得到了较好的拟合效果。  相似文献   

集合预报及其在中期天气预报中的应用   总被引：3，自引：1，他引：3       下载免费PDF全文

李小泉  刘金达  汪迎辉 《气象》1997,23(8):3-9

作者概述了集合预报的基本概念，集合预报中期天气预报中的意义与作用，现有的主要集合预报产品以及集合预报在美国美国国家气象中心和欧洲中期天气预报的业务运行。简要介绍了我国国家气象中心在动力延伸预报和集合预报方面的试验研究情况。  相似文献   

气球携带碘化银焰弹技术研究   总被引：1，自引：1，他引：1       下载免费PDF全文

秦长学 《气象》1997,23(11):11-13

主要介绍在北京地区开展气球携带碘化银焰弹雨雪作业的作业技术，经济效益等问题。通过各种增雨雪技术比较，认敢球携带碘化银焰弹增雨雪作业在北方干旱地区的抗旱工作中或作为收音机增雨雪作业的补充手段具有应用价值  相似文献   

STUDY ON THE AIR-SEA INTERACTION ON THE INTERANNUAL TIME SCALE IN THE SOUTH CHINA SEA^*     

Wang Dongxiao  Zhou Faxiu  Qin Zenghao 《Acta Meteorologica Sinica》1997,11(1):45-56

In this paper we document the correlationship between sea surface temperature(SST) and low level-winds such as sea level wind and 850 hPa wind in the South China Sea(SCS) based on COADS(1958-1987) and ECMWF objective analysis data(1973-1986).Further statistical analyses tell us that there is a fixed SCS basin mode for variations both of SST and low-level winds in the region on the interannual time scale due to air-sea interactions.A simplified,coupled model that is designed following the McCreary and Anderson's(1985) model and includes the feedback between the upper ocean and the circulation of East Asian monsoon demonstrates an interannual oscillation in the coupled air-sea system,which is similar to the observations in the SCS.  相似文献   

NUMERICAL SIMULATION OF OZONE DISTRIBUTIONS AND ITS VARIATION MECHANISM_*     

Ren Chuansen  Zhou Xiuji  Li Weiliang  Qin Yu 《Acta Meteorologica Sinica》1997,11(2):129-142

A 2-D global chemistry-transport model is set up in this paper.The model simulates the atmospheric ozone distributions well with specified dynamical conditions.The analysis of ozone variation mechanism shows that ozone is chemically in quasi-equilibrium except for the polar night region where the variation of ozone concentration is under the control of dynamical processes,that the oxygen atoms which produce ozone are mainly provided by the photolysis of O₂ in the upper stratosphere and by the photolysis of NO₂ in the lower stratosphere and the troposphere.and that the ozone is destroyed mainly by NO_x:the reactions between NO_x and O₃ and the odd oxygen cycle contribute 80% to more than 90% of the ozone destruction.  相似文献   

NUMERICAL STUDY ON DOMINATING FACTOR AND KEY AREA OF EL NINO CYCLE FORMATION_*     

Zhang Qin  Haines Keith 《Acta Meteorologica Sinica》1997,11(2):176-186

A coupled model,which is employed to study the dominating factor and key area of El Nino cycle formation,consists of a dynamical ocean model and a statistical atmospheric model.The coupled model with seasonal forcing successfully reproduces the El Nino event cycle which exhibits quasi-regular oscillations with a preferred period of about 4 years.The results show that the heat content(HC) is transported between the eastern and the western tropical Pacific areas.The spatial distribution of HC anomalies for four phases of the whole cycle clearly shows a possible formation mechanism of El Nino.Experiments further suggest that sea surface temperature in the tropical Pacific and HC in the central tropical Pacific are the most important factors and the central tropical Pacific is the most important area for determining formation of El Nino cycle.  相似文献   

Adjoint Matching Condition for Parameterized Discontinuities－A Derivation Using Lagrangian-form Costfunction     

Xu Qin  Qiu Chongjian 《大气科学进展》1997,14(1):49-52

The generalized adjoint property and adjoint matching condition for systems that contain discontinuous on / off switches are derived by a perturbation analysis of the Lagranging-form costfunction  相似文献   

区域持续发展的基本理论及其实践意义   总被引：6，自引：1，他引：6  

秦耀辰  陈世敏  王喜  卢向前  李志刚 《地理科学进展》1997,16(1):15-23

区域持续发展是从实践中提出的重大课题，理论滞后于应用为其基本现实。没有理论的行动是盲目的。区域持续发展理论建设已迫在眉睫。理论建设包括科学体系、理论基础、基本理论和核心理论层次，本文主要对其基本理论层进行论述，认为现代人地关系协调论、区域PRED系统论、区域发展控制论和人地相互作用潜力论构成了区域持续发展的基本理论，这些理论对于构建区域持续发展核心理论以及指导当前的区域持续发展实践有着极为重要的现实意义。  相似文献   

地球化学样品中硒的循序提取技术   总被引：11，自引：0，他引：11  

张忠  周丽沂 《岩矿测试》1997,16(4):255-261

研究开发了一种硒的循序偏提取步骤，将地球化学样品中的硒选择性地循序提取到六个“操作上”定义的相态中：水溶性硒（水提取）；吸附在氧化矿物和粘土矿物上配位可交换的亚硒酸根离子（０．１ｍｏｌ／ＬＫＨ２ＰＯ４提取）；与有机质结合的硒（０．１ｍｏｌ／ＬＮａ４Ｐ２Ｏ７提取）；与铁锰铝氧化物和碳酸盐结合的硒（４．０ｍｏｌ／ＬＨＣｌ提取）；硫化物中的硒（ＫＣｌＯ３＋浓ＨＣｌ提取）；硅酸盐残渣中以副矿物和被硅质包裹的硒微粒存在的硒（ＨＦ＋ＨＮＯ３＋ＨＣｌＯ４强混合酸溶解）。对提取步骤的可行性和实用性作了详细的讨论。  相似文献   

唐古拉山冬克玛底冰川雪层中淋溶作用的初步研究   总被引：7，自引：7，他引：7  

侯书贵  秦大河 《冰川冻土》1996,18(3):227-234

利用唐古拉山冬克玛底冰川雪坑和表层积雪样品的实测资料，初步探讨本区雪层中离子淋溶作用的特征，影响因素及其对冰芯记录的干扰。研究发现淋溶作用能够对数周至数月时间尺度的雪层记录产生“平滑”作用，但不会影响冰芯记录的长期变化趋势。  相似文献