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111.
电子地图工程化的研究与实践   总被引:4,自引:1,他引:3  
电子地图是一个动态发展的概念 ,其工程系统化是实现产业化的基础和前提。本文以工程系统化的观点讨论了电子地图开发生产的工艺流程、生产管理体系及质量保证体系等内容。并指出电子地图工程系统化中应注意的几个问题.  相似文献   
112.
文章从科技成果转化的重要性出发,分析了当前在测绘科技成果转化中存在的问题,提出一些解决这些问题的看法与建议。  相似文献   
113.
The distributions of dimethylsulfide (DMS) and its precursor, dimethylsulfoniopropionate (DMSP), were examined in the surface microlayer and corresponding subsurface water of the Yellow Sea, China, in April 2006. The average concentrations of DMS and DMSP of dissolved (DMSPd) and particulate (DMSPp) forms were 5.42 (1.78–12.75), 9.22 (2.85–19.73) and 17.50 (4.33–36.09) nmol L−1 in the subsurface water, and those in the surface microlayer were 4.92 (1.69–10.66), 17.08 (3.13–38.82) and 22.54 (4.85–47.24) nmol L−1, respectively. The enrichment factor (EF) of DMS in the microlayer ranged from 0.47 to 2.24 with a mean of 0.98. In contrast, DMSPd and DMSPp appeared to be enriched in the microlayer with average EFs of 1.98 and 1.39, respectively. A close correlation of integrated DMS, DMSPp and chlorophyll a concentrations for compiled data from all stations in the microlayer and the subsurface water indicated that phytoplankton biomass might play an important role in controlling the distributions of biogenic sulfurs in the study area. Moreover, a statistically significant relationship was found between the microlayer concentrations of DMS, DMSP and chlorophyll a and their subsurface water concentrations, suggesting a close linkage between these two water compartments. Interestingly, we observed higher biological production rates and consumption rates of DMS in the microlayer relative to the subsurface water. Furthermore, the DMS production rates were closely correlated both with DMSPd and chlorophyll a concentrations. Our study showed that the major sink of DMS in microlayer was escape into the atmosphere, which greatly exceeded its bacterial consumption. A preliminary estimate for average flux of DMS from the Yellow Sea to the atmosphere was 6.41 μmol m−2 d−1 during spring.  相似文献   
114.
对 2 0 0 2年 12月下旬河南低温冻害天气分析结果表明 :前期强冷空气影响及大范围降雪 ,造成了前期气温偏低 ,为低温天气产生提供了有利条件 ;地面积雪时间长、高空强冷平流补充南下与晴空辐射降温是形成此次低温冷害的主要原因 ;5 0 0、70 0hPa脊前偏北气流引导近地面冷高压东南移并持续控制河南是造成晴空辐射冷却的主要天气系统 ;空气湿度小 ,有利于夜间降温。数值预报对最低气温的预报有一定指示意义 :当日本 782和欧洲中心 85 0hPa的温度预报 <- 8℃ ,同时 2 4h地面变压预报值≤ 3hPa时 ,第二天凌晨可能会出现 - 10℃以下的低温  相似文献   
115.
为快速掌握区域内全部水泥企业的碳排放情况,在部分企业实际生产数据未知时,也能建立其生产碳排放清单,文中基于熟料生产特征,构建了可根据设备设计产能和运行时长两种参数来核算企业CO2排放的数值模型.以京津冀地区59条典型水泥熟料生产线的生产数据作为统计样本,借助Eviews对生产线的实际产能、熟料烧成煤耗与设计产能间的关系...  相似文献   
116.
Using the regional terrestrial Net Primary Production (NPP) from different observations and models over China, we validated the NPP simulations and explored the relationship between NPP and climate variation at interannual and decadal scales in the Modified Sheffield Dynamic Global Vegetation Model (M-SDGVM) during 1981–2000. M-SDGVM shows agreement with the NPP data from 743 sites under the Global Primary Production Data Initiative (GPPDI). The spatial and the zonal averaged NPP of M-SDGVM agree well with ...  相似文献   
117.
测绘成果目录发布系统的设计与实现   总被引:1,自引:0,他引:1  
采用当前流行的Service GIS和Silverlight技术建立测绘成果目录发布系统,解决了目前测绘生产部门数据管理和共享应用方面存在的问题。  相似文献   
118.
杜桂泉 《云南地质》2011,30(4):464-467,453
采用大型矿业软件DIMINE建立大红山铜矿矿山三维地质模型,进而用地质统计学方法对块体模型进行品位估值和储量计算,结果准确,可用于矿山生产阶段的资源评估、储量计算、矿山设计。  相似文献   
119.
邓亮  邓少东  张承飞 《贵州地质》2014,31(2):158-160
本文结合事故钻孔施工实例,简略介绍了钻探施工事故钻孔偏斜器的制作、施工工艺、钻进方法,提出了应用自制偏斜器绕开孔内遗留物继续钻进的注意事项。通过偏斜钻进,在保证钻孔质量的同时,达到钻孔地质目的,获得所需地质资料。  相似文献   
120.
The Belt and Road Initiative (B&R Initiative) is a crucial strategy to promote regional sustainable development in the new era. However, the realization of the B&R Initiative faces huge challenges because of the dual characteristics of a fragile eco-environment and strong dependence on ecological resources for economic development in the Belt and Road (B&R) countries. The ecological carrying capacity (ECC) is a crucial indicator for evaluating regional sustainable development. From the perspective of the relationship between the supply and consumption of ecological resources, this study uses net primary productivity data to measure the supply capacity of ecological resources, and it uses the agricultural production and trade data provided by the United Nations Food and Agriculture Organization to measure the level of ecological resource consumption. These supply and consumption data are then used to assess the ECC and ecological carrying status (ECS) of the B&R countries in 2017. The results show that: (1) The ECC of the B&R is 11.097 billion people; the ecosystem can also support 6.433 billion people, and the ECC is in a state of rich and surplus. (2) The ECS is polarized among the regions and countries along the B&R. Of the 65 countries, the ECC of 40 countries is in a rich and surplus state, mainly in Mid-East Europe and Southeast Asia, while the ECC of 19 countries is in severe overload, mainly in West Asia/Middle East. (3) Although the ecosystems still have ample carrying space in countries along the B&R, ecological protection is still facing enormous challenges during the implementation of the B&R Initiative combined with the internationally recognized ecological protection standards as well as the forecasts of the population and economic development. As the core content of building a new international trade network, the B&R Initiative will help to solve the spatial mismatch between the supply and consumption of ecological resources, which provides a new opportunity to coordinate the contradiction between the ecological protection and social demands of the B&R countries.  相似文献   
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