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151.
应用地理信息系统理论、技术和方法,针对煤炭生产管理中的地质测量问题,研究开发了煤矿地质测量信息系统(CMGIS)。在分析CMGIS系统目标的基础上,确立了符合煤炭生产管理实际需要的系统硬件配置和逻辑结构,着重论述了CMGIS的软件组成及系统功能。CMGIS较其它应用系统具有较强的图形功能,能较好地解决煤矿地质测量成图问题。 相似文献
152.
在通讯技术、计算机、现代光学等各个方面都要用到Walsh变换,又如:为了减少图象处理中的复杂性和压缩图象传输中图象所占的频带,就要借助干Walsh变换。在快速Walsh变换中,往往先考虑Walsh—Hadamard变换;然后经过置换,可以转化为Walsh—Kaczmarz变换、Walsh—Paley变换。根据这些变换阵之间的关系式,我们研究了并矢矩阵的性质,以及变换阵的约化(reduction)算子D(m)。在[1]中,各变换阵在D(m)作用下,是通过另一种算子即所谓扩展(expansion)箅子表示它们的递归关系,本文则直接从D(m)给出三种变换的递归关系,这在计算上更为方便一些。 相似文献
153.
中国城市PM2.5污染对居民主观幸福感的影响及支付意愿研究 总被引:1,自引:0,他引:1
利用2015年中国40个城市大规模问卷调查数据,采用贝叶斯多层级有序分类响应模型探讨了PM2.5污染对居民主观幸福感的影响,进而核算居民为减轻PM2.5污染的支付意愿。研究发现:PM2.5污染对主观幸福感具有显著的负向影响,PM2.5污染每增加1个单位,主观幸福感将下降0.040个百分点;家庭月收入对主观幸福感具有显著的正向影响,家庭月收入每增加1个单位,主观幸福感将提升0.026个百分点。支付意愿不仅受到家庭收入水平的影响,还受到居民所处城市空气质量的影响;在承受PM2.5污染的最初阶段,居民为改善空气质量的支付意愿最高。居民为改善空气质量愿意支付的金额平均为226元,占家庭月总收入的2.274%。 相似文献
154.
Choi Yosoon Nguyen Hoang Bui Xuan-Nam Nguyen-Thoi Trung Park Sebeom 《Natural Resources Research》2021,30(2):1141-1173
Natural Resources Research - This study aimed to develop and assess the feasibility of different machine learning algorithms for predicting ore production in open-pit mines based on a truck-haulage... 相似文献
155.
Nguyen Hoang Bui Xuan-Nam Tran Quang-Hieu Nguyen Dinh-An Hoa Le Thi Thu Le Qui-Thao Giang Le Thi Huong 《Natural Resources Research》2021,30(6):4695-4717
Natural Resources Research - Blast-induced ground vibration (GV) is a hazardous phenomenon in open-pit mines, and it has unquestionable effects, such as slope instability, deformation of... 相似文献
156.
???????????????????????????????????????????????????????????????????Crust2.0??????????????????????????????????????????????档??????????????????????????-????????????λ???е?????????20~35 km???????????????????????????????????10 19~10 22 Pas???????450~600 ?档 相似文献
157.
Natural Resources Research - Blasting is the most popular method for rock fragmentation in open-pit mines. However, the side effects caused by blasting operations include ground vibration, air... 相似文献
158.
Lanxue Dang Zhuo Chen Ming-Hsiang Tsou 《International journal of geographical information science》2019,33(8):1545-1568
This article reports the findings from simulating the spatial diffusion processes of memes over social media networks by using the approach of agent-based modeling. Different from other studies, this article examines how space and distance affect the diffusion of memes. Simulations were carried out to emulate and to allow assessment of the different levels of efficiency that memes spread spatially and temporally. Analyzed network structures include random networks and preferential attachment networks. Simulated spatial processes for meme diffusion include independent cascade models and linear threshold models. Both simulated and real-world social networks were used in the analysis. Findings indicate that the numbers of information sources and opinion leaders affect the processes of meme diffusion. In addition, geography is still important in the processes of spatial diffusion of memes over social media networks. 相似文献
159.
160.
Hoang Tran Jun Zhang Jean-Martial Cohard Laura E. Condon Reed M. Maxwell 《Ground water》2020,58(3):392-405
In mountain, snow driven catchments, snowmelt is supposed to be the primary contribution to river streamflows during spring. In these catchments the contribution of groundwater is not well documented because of the difficulty to monitor groundwater in such complex environment with deep aquifers. In this study we use an integrated hydrologic model to conduct numerical experiments that help quantify the effect of lateral groundwater flow on total annual and peak streamflow in predevelopment conditions. Our simulations focus on the Upper Colorado River Basin (UCRB; 2.8 × 105 km2) a well-documented mountain catchment for which both streamflow and water table measurements are available for several important sub-basins. For the simulated water year, our results suggest an increase in peak flow of up to 57% when lateral groundwater flow processes are included—an unexpected result for flood conditions generally assumed independent of groundwater. Additionally, inclusion of lateral groundwater flow moderately improved the model match to observations. The correlation coefficient for mean annual flows improved from 0.84 for the no lateral groundwater flow simulation to 0.98 for the lateral groundwater flow one. Spatially we see more pronounced differences between lateral and no lateral groundwater flow cases in areas of the domain with steeper topography. We also found distinct differences in the magnitude and spatial distribution of streamflow changes with and without lateral groundwater flow between Upper Colorado River Sub-basins. A sensitivity test that scaled hydraulic conductivity over two orders of magnitude was conducted for the lateral groundwater flow simulations. These results show that the impact of lateral groundwater flow is as large or larger than an order of magnitude change in hydraulic conductivity. While our results focus on the UCRB, we feel that these simulations have relevance to other headwaters systems worldwide. 相似文献