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291.
用水源热泵技术,将矿井回风、矿井水、洗浴废水、冷却水(风)中的低品位废热转变为供热热能。该热泵热回收技术系统可靠、经济效益好,可达到节能减排的目的。该文分析了矿井系统中的废热类型和应用原理,给出了矿井回风、矿井水、洗浴废水、冷却水(风)废热回收量的计算方法,并分析了山东济宁梁宝寺煤矿矿井废热回收供热系统设计实例。认为该技术的应用为矿区提供了生产、生活必备的热源和热水,节约了生产成本,保障了煤矿企业的绿色生产,改善了矿区周围的生活环境。  相似文献   
292.
293.
长白山火山区是我国具有潜在喷发危险的活火山,在2002~2005年火山活动性增强出现了岩浆房扰动。利用卫星遥感技术具有观测范围大、观测时间长且连续的优势。因此,本文利用对流层污染探测仪(MOPITT)和大气红外探测仪(AIRS)高光谱遥感数据提取了2002~2005年长白山天池火山区CO总量、O3总量、水汽总量和地表温度异常信息,讨论了高光谱遥感气体地球化学异常信息与火山活动性之间的关系,并对2002~2005年长白山天池火山区火山活动性进行了研究。结果表明,高光谱遥感数据观测到的气体地球化学(CO、O3、水汽)异常与地震、形变监测结果以及地面流体(CO2、He、H2)观测结果相一致,表明MOPITT和AIRS高光谱遥感卫星观测到的气体异常变化较好地反映了2002~2005年大规模的深部岩浆局部扰动。在2002~2005年火山活动期间,CO总量、O3总量、水汽总量和地表温度均出现了显著异常且异常出现时段相应准偏差显著增大,反映了气体逸出量在时间上具有不均一性,可能与火山、地震活动过程中地应力的作用和变化有关。从气体异常持续的时间以及地面观测结果综合分析,2002~2005年岩浆房扰动并没有产生长时间的地幔物质流的上升和迁移。在火山活动性增强的时间段内,地表温度出现异常低值,这可能与太平洋板块俯冲过程中引起的断裂拉张增强有关。此外,火山活动过程中逸出的气体进入大气圈产生大气化学反应也会导致高光谱遥感所观测到的气体地球化学异常。研究结果为2002~2005年长白山火山活动性的研究提供了来自高光谱遥感数据的气体地球化学新证据,也对高光谱分辨率遥感数据在火山活动规律的研究以及火山监测中的应用具有一定意义。  相似文献   
294.
The effects of local and remote wind forcing of water level heights in the Virginia Coast Reserve (VCR) are examined in order to determine the significant forces governing estuarine motions over subtidal time scales. Recent (1996–2008) data from tide and wind stations in the lagoon, a tide station to the north at Sandy Hook, NJ, and one offshore wind station at the Chesapeake Light Tower are examined. Sea surface height spectrum calculations reveal significant diurnal and semidiurnal tidal effects along with subtidal variations, but a suppressed inertial signal. Sea-surface heights (SSH) with 2–5 day periods at Wachapreague, VA are coherent with those at Sandy Hook and lag them in time, suggesting that southward-propagating continental shelf waves provide subtidal variability within the lagoon. The coherence between lagoon winds and sea surface height, as well as between winds and cross-lagoon sea height gradient, were significant at a relatively small number of frequency and wind direction combinations. The frequencies at which this wind forcing occurs are the tidal and subtidal bands present to the north, so that lagoon winds selectively augment existing SSH signals, but do not generate them. The impact of the wind direction is closely related to the geometry of the lagoon and bounding landmasses. The effect of wind stress is also constrained by geometry in affecting the cross-lagoon water height gradient. Water levels at subtidal frequencies are likely forced by a combination of local wind forcing, remote wind forcing and oceanic forcing modified by the complex topography of the lagoon, shelf, and barrier islands.  相似文献   
295.
Nutrient supply in the area off Northwest Africa is mainly regulated by two processes, coastal upwelling and deposition of Saharan dust. In the present study, both processes were analyzed and evaluated by different methods, including cross-correlation, multiple correlation, and event statistics, using remotely sensed proxies of the period from 2000 to 2008 to investigate their influence on the marine environment. The remotely sensed chlorophyll-a concentration was used as a proxy for the phytoplankton biomass stimulated by nutrient supply into the euphotic zone from deeper water layers and from the atmosphere. Satellite-derived alongshore wind stress and sea-surface temperature were applied as proxies for the strength and reflection of coastal upwelling processes. The westward wind and the dust component of the aerosol optical depth describe the transport direction of atmospheric dust and the atmospheric dust column load.  相似文献   
296.
青海日月山断裂带是青藏高原东北缘柴达木—祁连活动地块内部的一条NNW走向的右旋走滑兼逆冲断裂。 本文基于ENVI 5.1遥感图像处理平台对研究区高分一号多光谱(分辨率8 m)和全色(分辨率2 m)影像进行融合, 获取了高保真、 高分辨率的卫星遥感影像。 通过多尺度、 多角度、 多层次的构造解译以及对比, 将日月山西支断裂的海晏段划分为德州段(F1-3)和海晏段(F1-4)两个次级段, 同时利用高分辨率Google Earth影像对德州段断错微地貌进行了解译、 分析, 结合对德州段野外地质考察, 进一步验证了影像解译结果。 研究表明: 日月山断裂的德州段由5条次级段落组成(f1, f2, f3, f4, f5), 并且该段断裂晚更新世以来活动性明显, 以右旋走滑为主兼有逆倾滑分量; 断裂在晚更新世以来发生过多期断层活动, 其中全新世断层活动可划分为两期, 最新一期水平位错量为6.5~8.7 m, 第二期水平位错量为12.3~14 m; 晚更新世也可划分出两期活动, 第一期水平位错量为16~20 m, 第二期水平位错量为28.5~47 m。  相似文献   
297.
This work investigates the likelihood of integrating the cheap and readily-available broadband multispectral MODIS data and in-situ measurements in quantifying and monitoring water quality status of an inland lake within Upper Manyame Catchment in Zimbabwe. Specifically we used MODIS images to quantify inland lake chlorophyll_a concentrations, as a proxy for predicting lake pollution levels. The findings of this study show a high chlorophyll_a concentration of 0.101 ± 0.128 μg/L within the Lake. The results further demonstrated that the chlorophyll_a concentration levels did not significantly vary (p = 0.788) between sites, except among depths (p = 0.05). Further, prediction results based on the relationship between observed and predicted chlorophyll_a produced a high R2 value of 0.89 and a root mean square error (RMSE) value of 0.003 μg/L. Moreover, the derived landuse maps of Upper Manyame Catchment indicated a significant variation in the percentage settlement in 1985, 1994 and 2010 change from 1985 to 2010. For instance, 8% increase in settlement in the period between 1994 and 2010 and over 12% increase from 1985 to 2010 and a decline in percent forest coverage (i.e. 9.8% in 1985 to 2.0% in the year 2010) in the catchment was observed. Overall, the findings of this study highlights the importance of free and readily-available satellite datasets (such as the multispectral MODIS and Landsat) in quantifying and monitoring water quality across inland lakes especially in data-scarce areas like Sub-Saharan Africa.  相似文献   
298.
The Siruyeh landslide occurred at the eastern side of the Siruyeh valley, 22 km west of Semirom city, south of Esfahān on 25th March, 2005 with large dimensions (2,400 m long, 450 m wide with total area of 1 km2). The sliding mass blocked the Siruyeh River making a 35-m-high natural dam and 6-acre lake 570,000 m3 in volume that poses a potential threat for the area. The landslide occurred in soil and intensely weathered marls of the Tarbur and Kashkan Formations (upper Cretaceous–Paleocene age). The overall comparison and interpretation of the gathered evidence from satellite images, field trips, and laboratory tests show that the most important factors involved in triggering the Siruyeh landslide in order of importance are heavy precipitation and snow melt and intense concentration of faults and fractures as well as weathered and weak lithology.  相似文献   
299.
Social data from census and household surveys provide key information for monitoring the status of populations, but the data utility can be limited by temporal gaps between surveys. Recent studies have pointed to the potential for remotely sensed satellite sensor data to be used as proxies for social data. Such an approach could provide valuable information for the monitoring of populations between enumeration periods. Field observations in Assam, north-east India suggested that socioeconomic conditions could be related to patterns in the type and abundance of local land cover dynamics prompting the development of a more formal approach. This research tested if environmental data derived from remotely sensed satellite sensor data could be used to predict a socioeconomic outcome using a generalised autoregressive error (GARerr) model. The proportion of female literacy from the 2001 Indian National Census was used as an indicator of socioeconomic conditions. A significant positive correlation was found with woodland and a significant negative correlation with winter cropland (i.e., additional cropping beyond the normal cropping season). The dependence of female literacy on distance to nearest road was very small. The GARerr model reduced residual spatial autocorrelation and revealed that the logistic regression model over-estimated the significance of the explanatory covariates. The results are promising, while also revealing the complexities of population–environment interactions in rural, developing world contexts. Further research should explore the prediction of socioeconomic conditions using fine spatial resolution satellite sensor data and methods that can account for such complexities.  相似文献   
300.
Abstract

Many data structures are possible for the storage of topological information for computer-based maps. The PAN graph is here suggested as an aid in the selection of a strategy appropriate to the application. Examples are given for the mapping of triangular networks and Thiessen polygons. Application of the technique is appropriate to both education in, and design of, spatial data structures for automated cartography and geographical information systems  相似文献   
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