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1.
张旗  陈春晓 《浙江气象》2003,24(3):15-18,41
结合现阶段气象信息数据库化业务工作的实践,系统地介绍利用ADO技术开发数据库应用程序的方法,并与使用其他方法编制的数据库应用程序进行了比较,对基于ADO技术的数据库管理、监控模式和实现方法进行了初步探讨。  相似文献   

2.
数据库发展综述   总被引:2,自引:0,他引:2  
较详细地介绍了数据库的概念,发展动态以及未来展望,并描述了多媒体数据处理,分布式数据库系统以及数据库间的数据转换等,为从事数据库开发研究的人员提供参考和启发。  相似文献   

3.
陈瑾文 《贵州气象》2002,26(4):38-40,21
着重分析了Web数据库的几种动态发布方案及其优缺点,阐述网站Web数据库的一些技术特点,并介绍一个Web数据库动态发布的过程。  相似文献   

4.
田兰 《贵州气象》2002,26(3):32-35
介绍在“9210”Sybase数据库系统管理与维护中的几个主要方法,包括:日志管理、数据库一致性检查、数据空间管理及数据库的备份与恢复,希望能为装有Sybase数据库的台站的系统管理员提供一些帮助。  相似文献   

5.
魏华兵 《湖北气象》2002,21(3):24-26
用时,段分类法对地面气象资料进行分类,通过分类数据库的建立、数据录入和特殊数据的量化处理,形成分类气象资料数据库;利用数据库资料,进行统计和查询服务,基于这一思路,用FoxPro语言编写了赤壁市气候资料系统。  相似文献   

6.
民航气象数据库自1999年正式运行以来,为航空气象预报提供了丰富的数值预报格点产品和图形产品,但格点数据GRIB码属变网格资料,需解码到标准网格点上,另外在数据库工作站上显示图形不直观某些要素也不能迭加,考虑到这点,民航西南空管局气象中心把民航数据库资料GRIB解码应用到MICAPS工作站上,解决了上述问题,使民航气象数据库资料得到了更广泛和直观的应用。  相似文献   

7.
从我省省、地(市)两级数据库建设与管理的要求出发,研究了数据库的内容及数据结构模型,为数据库管理设计了数据字典、数据维护及数据服务等基本功能模块。  相似文献   

8.
利用智能数据库作降水预报   总被引:1,自引:0,他引:1  
利用智能数据库作降水预报杨志东吉林省气象台1引言由于智能数据库可以对常规报文做自动图形特征提取和归档,并形成历史数据,我们就有可能对这一数据库作历史的统计、整理,总结出一些预报方法来。本文将对我们如何利用0、l回归分析对数据库的知识版行分析和预报做一...  相似文献   

9.
介绍了河南省气象通信业务管理数据库。该数据库采用最新关系型数据库管理系统-汉字FOXBASE PLUS(V2.10)在微型计算机上建立。数据库管理系统与DBASEⅢPLUS数据库管理系统100%兼容,且功能比后者又有许多扩充和增强,运算速度也比后者快5.9倍。  相似文献   

10.
从我省省、地(市)两级数数据库建设与管理的要求发出,研究了数据库的内容及数据结构模型,为数据库管理设计了数据字典、数据维护及数据服务等基本功能模块。  相似文献   

11.
Storms that occur at the Bay of Bengal (BoB) are of a bimodal pattern, which is different from that of the other sea areas. By using the NCEP, SST and JTWC data, the causes of the bimodal pattern storm activity of the BoB are diagnosed and analyzed in this paper. The result shows that the seasonal variation of general atmosphere circulation in East Asia has a regulating and controlling impact on the BoB storm activity, and the “bimodal period” of the storm activity corresponds exactly to the seasonal conversion period of atmospheric circulation. The minor wind speed of shear spring and autumn contributed to the storm, which was a crucial factor for the generation and occurrence of the “bimodal pattern” storm activity in the BoB. The analysis on sea surface temperature (SST) shows that the SSTs of all the year around in the BoB area meet the conditions required for the generation of tropical cyclones (TCs). However, the SSTs in the central area of the bay are higher than that of the surrounding areas in spring and autumn, which facilitates the occurrence of a “two-peak” storm activity pattern. The genesis potential index (GPI) quantifies and reflects the environmental conditions for the generation of the BoB storms. For GPI, the intense low-level vortex disturbance in the troposphere and high-humidity atmosphere are the sufficient conditions for storms, while large maximum wind velocity of the ground vortex radius and small vertical wind shear are the necessary conditions of storms.  相似文献   

12.
A review of recent advances in research on Asian monsoon in China   总被引:6,自引:0,他引:6  
This paper reviews briefly advances in recent research on monsoon by Chinese scholars, including primarily: (1) the establishment of various monsoon indices. In particular, the standardized dynamic seasonal variability index of the monsoon can delimit the geographical distribution of global monsoon systems and determine quantitatively the date of abrupt change in circulation. (2) The provision of three driving forces for the generation of monsoon. (3) The revelation of the heating-pump action of the Tibetan Plateau, which strengthens southerlies in the southern and southeastern periphery of the Plateau and results in a strong rainfall center from the northern Bay of Bengal (BOB) to the Plateau itself. (4) Clarification of the initial onset of the Asian Summer Monsoon (ASM) in the BOB east of 90°E, Indochina Peninsula (ICP) and the South China Sea, of which the rapid northward progression of tropical convection in the Sumatra and the rapid westward movement of the South Asia High to the Indochina Peninsula are the earliest signs. (5) The provision of an integrated mechanism for the onset of the East Asian Summer Monsoon (EASM), which emphasizes the integrated impact of sensible heat over Indian Peninsula, the warm advection of the Tibetan Plateau and the sensible heat and latent heat over the Indochina Peninsula on the one hand, and the seasonal phase-lock effect of the northward propagation of low frequency oscillation on the other. (6) The revelation of the "planetary-scale moisture transport large-value band" from the Southern Hemisphere through to the Asian monsoon region and into the North Pacific, which is converged by several large-scale moisture transport belts in the Asian-Australian monsoon regions and whose variation influences directly the temporal and spatial distribution of summer rainfall in China. (7) Presenting the features of the seasonal advance of the EASM, the propagation of intraseasonal oscillation, and their relationship with rainfall in Ch  相似文献   

13.
A one-dimensional, time-dependent cloud model with parameterized microphysics is used to investigate the processes which control the rainout and washout of soluble gases from warm, precipitating stratiform clouds. Calculations are presented simulating the distributions of soluble species within and below the cloud layer and in the precipitating raindrops as a function of time and species' solubility. Our calculations indicate that for species with low solubility, wet removal processes are relatively slow and thus do not significantly affect the species' gas-phase abundance. As a result, the removal of low-solubility species by rainout and washout is controlled by thermodynamic processes with the concentration of the species in cloud and rainwater largely determined by the species' solubility. For highly soluble species on the other hand, dissolution into cloud droplets and removal in rain is quite rapid and the abundance of highly soluble species within and below the cloud falls rapidly as soon as the precipitation begins. Because of this rapid decrease in concentration, we find that for highly soluble species: concentrations in cloud droplets near the cloud base can exceed that of raindrops by factors of 2 to 10; washout can dominate over rainout as a removal mechanism; and that, after an extended period of rainfall, the rate of removal becomes independent of the microphysical properties and rainfall rate of the cloud and is controlled by the rate of transport of material into the precipitating column by horizontal advection.  相似文献   

14.
The Fe(II)/Fe(III)-partition in cloudwater samples collected during two field campaigns is evaluated. It turned out that the simultaneous occurrence of complexing and reducing substances in the atmosphere and the cloud processing increase the solubility of iron compounds present in aerosol particles. A correlation between the concentration of iron(II) in the liquid phase and the intensity of the solar irradiation was observed for most of the cloudwater samples. This could be due to the fact that both the photochemical reduction of the iron(III) complexes and the photochemical reductive dissolution of iron(III)(hydr)oxides are depending on the pH-value. Iron(II) seems to be oxidised back to iron(III) preferably by hydrogen peroxide during the night. Positive correlations were received e.g. between the concentration of dissolved iron and the concentration of oxalate and between the percentage of iron(III) and the concentration of hydrogen peroxide. A negative correlation was found e.g. between the concentration of dissolved iron and the pH-value. The uncertainty of the whole process of sampling and analysis was investigated and the conformity of the results was satisfying considering the sometimes difficult conditions during a field campaign.  相似文献   

15.
在给出霾的定义、特征及空间分布的基础上,介绍了霾的物理学特性、化学特性及气象学研究的最新进展,分析了霾对公共卫生健康、交通安全的影响, 提出了科学编制防御规划、统筹建立协调机制、有效推进减霾行动、提供相应科技支撑、完善相关政策法规等对策建议,对于政府相关部门制定霾天气应对和防治措施具有积极的决策参考作用,减少或减轻霾对经济社会发展和人体健康带来的损害威胁。  相似文献   

16.
为保证各类气象设备和网络稳定运行,出现故障及时通知到人,针对目前气象设备监视和报警存在的问题,设计开发气象设备及网络监控报警软件,出现异常情况通过钉钉机器人开放接口发送报警信息到手机和电脑钉钉群,提醒业务人员及时处理故障,实现气象设备、网络情况自动监控,自动报警功能。通过业务运行表明,该软件在气象设备及网络监控业务中能提高发现设备和网络故障的时效,自动化程度高,缩短了维护人员处理故障的时效性,是钉钉机器人在气象设备和网络监测报警应用的积极探索。  相似文献   

17.
人工影响天气弹药仓储、运输困难严重影响安全作业。以湖南省人工影响天气弹药储运为例,从现代管理技术和机制上探讨人工影响天气弹药储运安全保障措施。结果表明,采用分区划片、区域保障的仓储原则可以解决炮弹火箭弹禁止混存的问题;通过物联网系统建设实现弹药信息化科学管理,通过构建政府主导、军地协同、部门落实的人工影响天气弹药安全保障体系,能适应政府和军区改革。新形势下军地协同保障弹药储运促进了人工影响天气事业的安全发展。  相似文献   

18.
通过对1999年12月广西严重霜冻天气同期500hPa高度场和海平面气压场特征及前期500 hPa高度的相关场分析,得到北半球中高纬度槽脊的位置与强度,地面大陆冷高压强弱,是影响广西12月霜冻的主要环流形势;当年1月、9月极涡强度、位置,北美高压脊强度,及黑海附近低槽强弱,是影响广西12月霜冻天气重、轻的重要因子。  相似文献   

19.
Based on the primitive equations of the atmosphere,we study the effects of external forcing.dissipation and nonlinearity on the solutions of stationary motion and non-stationary motion.Theresults show that the asymptotic behavior of solutions of the forced dissipative nonlinear system isessentially different from that of the adiabatic non-dissipative system,the adiabatic dissipativesystem,the diabatic non-dissipative system and the diabatic dissipative linear system,and that thejoint action of external forcing,dissipation and nonlinearity is the source of multiple equilibria.From this we can conclude that the important actions of diabatic heating and dissipation must beconsidered in the models of the long-term weather and the climate.  相似文献   

20.
枯季是水旱、水生态和水资源问题的重要时期,枯季径流的变化直接影响着河流生态和流域水资源管理。基于中国网格气象数据和主要江河枯季径流资料,初步分析了1961—2018年中国气候变化趋势和主要江河枯季径流演变特征与成因。结果表明,全国枯季平均气温显著上升,北方地区升温较早,南方地区2001—2018年升温明显。全国约84%的地区枯季降水有增加趋势,其中约42.2%的地区增加显著;全国枯季降水呈现西北、东北和东南显著增加,中部变化不显著格局。黄河中游和海河枯季径流下降显著,2001—2018年黄河中游枯季径流较1961—1980年减少了34%,同时期海河流域枯季径流量减少幅度均超过80%;松花江上游和长江流域枯季径流增加显著,2001—2018年松花江上游枯季径流量增加了约67%,长江流域枯季径流量增加了约16%。枯季降水增加主导了松花江上游、辽河、淮河、长江以及珠江枯季径流的增加;气温的显著上升对黄河中游和海河等地枯季径流有显著负向作用;人类活动是松花江中游、黄河和海河枯季径流下降的主要影响因素。尽管全国枯季降水的增加对于缓解流域生态和水资源问题有积极作用,但人类活动和气温显著上升加速了水资源的消耗,加大了流域水资源脆弱性。  相似文献   

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