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1.
NCAR绘图软件在Windows下的编程   总被引:2,自引:1,他引:2  
介绍了NCAR绘图软件在Windows下的编程方法和具体实现,解决了在科研绘图工作中遇到的一些实际问题,对在Windows下编程的静态链接和动态链接进行了分析和研究,为Fortran编程员提供了在Windows下编程的基础。  相似文献   
2.
针对现有气候统计诊断与预测程序在通用性方面的不足,以线性趋势估计的源程序为例,介绍了在微机平台上,利用Fortran90的动态数组特性,通过增加参数控制文件增强该程序通用性的思路和方法,并利用VisualBasic语言对改进后的程序进行可视化设计,增强了程序的易用性。  相似文献   
3.
OPA 90 set out stringent requirements and liabilities for tankers operating in US national waters. OPA 90 was in response to the public concern caused by the grounding of the Exxon Valdez in 1989. It made ship owners responsible for the cost of pollution incidents and required all tank ships/barges operating in US waters have double hulls by 2015. We model factors influencing oil spills and test whether OPA 90 helped reduce the number of those spills. After accounting for causal factors, both increased liability and double hulls were statistically significant factors in reducing the number of spills.  相似文献   
4.
针对现有气候统计诊断与预测程序在通用性方面的不足,以线性趋势估计的源程序为例,介绍了在微机平台上,利用Fortran 90的动态数组特性,通过增加参数控制文件增强该程序通用性的思路和方法,并利用V isualBasic语言对改进后的程序进行可视化设计,增强了程序的易用性。  相似文献   
5.
地磁日变观测质量主要与仪器性能和观测点的环境有关。本文重点研究了目前在地磁日变测量中主要采用的HC90D氦光泵磁力仪的信号失锁问题,日变站的选址二个对于最终观测精度影响很大的问题,并提出了具体的解决方法。  相似文献   
6.
Climate warming is having profound effects on the hydrological cycle by increasing atmospheric demand, changing water availability, and snow seasonality. Europe suffered three distinct heat waves in 2019, and 11 of the 12 hottest years ever recorded took place in the past two decades, which will potentially change seasonal streamflow patterns and long-term trends. Central Europe exhibited six dry years in a row since 2014. This study uses data from a well-documented headwater catchment in Central Europe (Lysina) to explore hydrological responses to a warming climate. We applied a lumped parameter hydrologic model Brook90 and a distributed model Penn State Integrated Hydrologic Model (PIHM) to simulate long-term hydrological change under future climate scenarios. Both models performed well on historic streamflow and in agreement with each other according to the catchment water budget. In addition, PIHM was able to simulate lateral groundwater redistribution within the catchment validated by the groundwater table dynamics. The long-term trends in runoff and low flow were captured by PIHM only. We applied different EURO-CORDEX models with two emission scenarios (Representative Concentration Pathways RCP 4.5, 8.5) and found significant impacts on runoff and evapotranspiration (ET) for the period of 2071–2100. Results from both models suggested reduced runoff and increased ET, while the monthly distribution of runoff was different. We used this catchment study to understand the importance of subsurface processes in projection of hydrologic response to a warming climate.  相似文献   
7.
Fourteen acoustic Doppler current profilers (ADCPs) were deployed on the shelf and slope for 1 year just west of the DeSoto Canyon in the Northeastern Gulf of Mexico by the Naval Research Laboratory (NRL) as part of its Slope to Shelf Energetics and Exchange Dynamics (SEED) project. The winter and spring observations are discussed here in regards to the low-frequency current variability and its relation to wind and eddy forcing. Empirical orthogonal function (EOF) analyses showed that two modes described most of the current variability. Wind-forced variability of the along-shelf flow was the main contributor in Mode 1 while eddies contributed much of the variability in Mode 2. Wind-stress controlled currents on the shelf and slope at time scales of about a week. On longer time scales, variations in the currents on both the outer shelf and slope appear to be related to seasonal variations in the time-cumulated wind stress curl. Winds were dominant in driving the along-shelf transports, particularly along the slope. However, the effective wind stress component was found to be aligned with the west Florida shelf direction rather than the local shelf direction. Eddy intrusions, which were more numerous in winter and spring than in summer and fall, and winds were found to contribute significantly to cross-shelf exchange processes.  相似文献   
8.
大亚湾不同介质中137Cs和90Sr的含量及行为特征   总被引:1,自引:0,他引:1  
刘广山  周彩芸 《台湾海峡》2000,19(3):261-268
分别用HPGeγ谱方法和放化分离β计数方法测量了大亚湾海水、沉积物和海洋生物样品的人工放射性核素^137Cs和^90Sr。计算了海洋生物对^137Cs和^90Sr的浓集因子及其在沉积物和海水中的分配系数,对^137Cs和^90Sr的含量水平,^137Cs和^90Sr及其与样品中天然放射性核素含量相关性,海洋生物对^137Cs和^90Sr的浓集,以及^137Cs和^90Sr的地球化学进行了讨论。  相似文献   
9.
 The U.S. Geological Survey and Idaho State University, in cooperation with the U.S. Department of Energy, conducted a study to determine strontium distribution coefficients (Kds) of surficial sediments at the Idaho National Engineering and Environmental Laboratory (INEEL). Batch experiments using synthesized aqueous solutions were used to determine Kds, which describe the distribution of a solute between the solution and solid phase, of 20 surficial-sediment samples from the INEEL. The Kds for the 20 surficial-sediment samples ranged from 36 to 275 ml/g. Many properties of both the synthesized aqueous solutions and sediments used in the experiments also were determined. Solution properties determined were initial and equilibrium concentrations of calcium, magnesium, and strontium, pH and specific conductance, and initial concentrations of potassium and sodium. Sediment properties determined were grain-size distribution, bulk mineralogy, whole-rock major-oxide and strontium and barium concentrations, and Brunauer-Emmett-Teller (BET) surface area. Solution and sediment properties were correlated with strontium Kds of the 20 surficial sediments using Pearson correlation coefficients. Solution properties with the strongest correlations with strontium Kds were equilibrium pH and equilibrium calcium concentration correlation coefficients, 0.6598 and –0.6518, respectively. Sediment properties with the strongest correlations with strontium Kds were manganese oxide (MnO), BET surface area, and the >4.75-mm-grain-size fraction correlation coefficients, 0.7054, 0.7022, and –0.6660, respectively. Effects of solution properties on strontium Kds were interpreted as being due to competition among similarly charged and sized cations in solution for strontium-sorption sites; effects of sediment properties on strontium Kds were interpreted as being surface-area related. Multivariate analyses of these solution and sediment properties resulted in r2 values of 0.8071 when all five properties were used and 0.8043 when three properties, equilibrium pH, MnO, and BET surface area, were used. Received: 30 November 1998 · Accepted: 16 February 1999  相似文献   
10.
基于 GIS 的南海台风风浪预报系统   总被引:1,自引:0,他引:1  
探索了以组件式 GIS 为平台集成风场与海浪数值模型的关键技术研究及其实现过程,成功构建了南海台风风浪预报系统.该系统实现了数值模型计算所有阶段,即模型前处理、模型计算、模型后处理以及模型计算结果与 GIS 的无缝集成,大大提高了模型应用的可操作性和决策效率.经半年以上时间的使用,取得了良好的运行效果.  相似文献   
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