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为了做好政府的公共气象服务,改善当前服务产品形式单一的局面,作者重点研究了MICAPS软件下的风云卫星云图实现在线浏览和定量分析的关键技术。首先结合ArcGIS Engine完成了该类云图向多波段栅格img格式的转换,生成了自带颜色和投影坐标的栅格云图。然后采用ArcGIS Server构建了栅格云图的网络发布平台,实现了云图在Web环境下的发布、查询和浏览,并采用GIS统计分析方法,提出并实现了云图的定量统计与分析。经测试,该平台可高效地运行于当前Web环境,完全能够适应当前带宽传输及满足主流电脑浏览和分析的需要。该平台应用到包头市公共气象服务系统中,使当地气象局在公共气象服务平台的建设方面迈进了一大步,为公众了解气象和预报员制作气象预警预报提供了一个气象信息辅助决策平台。 相似文献
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通过分析辉铜山铜矿体特征及矿山开采时深部找矿成果,发现矿体具SE向倾伏趋势,地表被大面积第四系覆盖。对测区岩(矿)石进行物性测量,发现区内矿石具高极化中低阻电性特征,与围岩电性差异明显,可用激发极化法进行深部地球信息探测。在1∶1万矿区地质填图基础上,采用激电中梯和激电测深2种方法进行矿产勘查,圈定2处明显的激电异常。结合区内地质特征和钻孔资料,发现高极化中低阻激电异常与推测的隐伏铜矿体具良好的空间对应关系,显示该矿区具良好的深部找矿潜力,为进一步详查工作提供了依据。 相似文献
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教学中知识是有结构的,学生是创建结构化知识的主体对象。创建学科结构化知识教学需走出"必备知识碎片化""非必备知识结构化""必备知识结构错误化""知识结构化教学设计粗放化"等偏向。以学为中心的学科概念教学是创建结构化知识教学的本质特征。创建学科结构化知识的结构化教学旨趣是遵循认知规律、学为中心、结构价值的流程。 相似文献
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Xuetao Zhu Yun-chao Lang Jun Zhong Hu Ding Huijun He Zhifeng Yan Si-liang Li 《中国地球化学学报》2018,37(4):509-518
In order to better understand the relative importance of hydrologic variation and anthropogenic disturbance and their complex interactions within the trace elemental geochemical cycle, water samples were collected monthly over 1 year in the Min River, eastern Tibetan Plateau, and analyzed for trace element composition. The dissolved trace elements exhibited different relationships with increasing discharge compared with major elements. The elements analyzed can be divided into three groups according to their behavior in response to changing discharge: (1) elements that showed weak positive correlation with discharge, e.g. Cu, V, and Ba; (2) elements that exhibited weak negative correlation with discharge, including Rb, Sr, Pb, Sb, Zn, Cr, Cd, and U; and (3) elements that displayed no significant correlation with variation in discharge, e.g. Ti, Fe, Co, Ni, and As. Cu was strongly affected by anthropogenic activities and flushed into the river with increasing discharge. Ba has a strong solubility in the terrestrial environment, dissolved quickly, and was released into the river. The positive relationship between V concentration and discharge may be attributed to secondary reactions, such as precipitation and adsorption on oxides and aluminosilicate clays. Conservative behavior had an impact on the geochemical behavior of Sr and Rb across hydrologic variation. Pb, Zn, Sb, Cd, and Cr underwent a mild dilution effect connected with anthropogenic activities. The chemostatic behavior of U was regulated by carbonate dissolution and biological uptake. In addition, higher temperatures enhanced biotic activities, affecting the concentrations of Fe and Ni. The relationship between power law slopes and coefficient of variation for discharge and solute concentration suggests that concentrations of trace elements vary significantly with increasing discharge compared with major elements. Silicate mineral weathering had less effect on the fluvial solutes with increasing discharge. Mining activity may exert an additional control on concentration–discharge dynamics of anthropogenic trace elements. 相似文献
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基于欧洲中期天气预报中心第五代季节预测系统SEAS5模式的历史回报数据和新疆98个气象站的气温、降水观测资料,利用距平符号一致率Pc、趋势异常综合评分Ps、距平相关系数ACC、时间相关系数TCC等方法,综合评估SEAS5模式对新疆1993—2019年月尺度气温和降水的预测性能。结果表明:SEAS5模式对新疆月气温、降水的总体预测性能较好,对降水趋势和量级有一定的预测能力。模式的预测性能存在明显的月际差异和空间差异。模式对新疆4—9月气温和4月、6—8月降水的预测性能较好。气温预测评分中,4月Pc最高(61.3分),7月Ps最高(74.4分),6月ACC最高(0.17)。降水预测评分中,4月Pc最高(58.7分),7月Ps最高(72.1分),4月ACC最高(0.16)。空间分布上,模式对1、3、6和12月南疆的气温预测性能普遍高于北疆,对7和9月南疆西部的预测性能低于其他地区。模式对南疆的降水预测性能普遍高于北疆。 相似文献
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Jing Liu Siliang Li Jun Zhong Xuetao Zhu Qingjun Guo Yunchao Lang Xiaokun Han 《中国地球化学学报》2017,36(4):611-618
While it is critical to accurately understand the sources and transformation of sulfate based on time-series analysis, there are limited studies on temporal variation of sulfate in rivers and on rock weathering by sulfuric acids. We conducted a monthly sampling campaign in the Beipan, Nanpan, and Hongshui Rivers over the course of one hydrological year. This study examined seasonal variations in riverine sulfate impacted by the monsoon climate in the upper reaches of the Xijiang River basin. In general, the SO4 2? contents in these rivers dropped from relatively high levels to low values during the high-flow season, in response to increasing discharge. The sulfate was generally enriched in heavy isotopes during the low-flow season compared to the high-flow season. The calculated results indicate that the riverine sulfate was mainly derived from sulfide oxidation, but that evaporite dissolution could be an important source during the low-flow season, based on isotopic evidence. Mine drainage is likely an important source of sulfate to these rivers during the high-flow season due to contributions from fast surface flow, which responds to frequent heavy rain in monsoonal climate regions. A relatively high proportion of HCO3 ? was found to be derived from rock weathering by sulfuric acid during the high-flow season when compared to that observed during the low-flow season. The results suggest that approximately one quarter of the HCO3 ? in the Hongshui River originated from carbonate weathering by sulfuric acid derived from the oxidation of sulfide. Such information on the specific dual isotopic characteristics of riverine sulfate throughout a hydrological year can provide unique evidence for understanding the temporal variability of sulfate concentrations and weathering processes in rivers. 相似文献
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Natural Hazards - At present, the wind and snow loads are calculated independently when determining the design specifications for building structures. Yet, when snow drifting occurs, the basic wind... 相似文献