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随着我国城市化程度的进一步提高,城市无形资产在城市发展中的地位和作用愈发凸显。本文从城市经营的角度出发,探讨了城市无形资产经营的内容和重要意义,对廊坊市城市无形资产经营进行了分析,并提出了提升城市无形资产经营的相应建议。 相似文献
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在城市峡谷中通过接收导航卫星信号以实现连续的定位与测速一直是卫星导航应用中的一个难题。针对此问题,借鉴卫星导航对抗中转发式欺骗干扰的定位控制基本原理,提出了通过分布式单星转发来解决城市峡谷中实现连续卫星导航的新方法,并构建了分布式单星转发的定位测速模型。在此基础上详细讨论了转发器天线对被遮挡卫星的指向跟踪、转发器相关参数的获取、转发器收发之间的有效隔离、直达信号与转发信号的同时利用等应用性问题。所提出方法的可行性得到了仿真试验的有效验证,从而为城市峡谷中的卫星导航应用提供了新的参考。 相似文献
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Samy A. Khalil A.M. Shaffie 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2013
The hourly and daily measured clear-sky global solar radiation (G) and biologically important effective erythematic radiation (EER) incident on a horizontal surface at Cairo, Egypt (latitude 30° 05′ N & Longitude 31° 15′ E), during the period from January 1995 to December 2005 are used in this paper. The relationship between daily integrated totals of EER and the daily totals of broadband global solar radiation (250–2800 nm) is established. The temporal variability of the percentage ratio of the total daily erythema to total daily broadband solar global irradiation (EER/G) is determined. The monthly and the seasonal averages of the extraterrestrial UVB solar radiation, Mesurad and estímated UVB solar radiation and clearness index KtUVB of UVB radiation are discussed. The average monthly mean variation of slant ozone (Z) and UVB transmission (KtUVB) at the present work are found. The two variables show an opposite seasonal behavior, and the average monthly of slant ozone column and UVB transmission values shows the relationship between them in a clearer way than those of daily values. The estimated values of UVB solar radiation a good agreement with the measured values of the UVB solar radiation, the difference between the estimated and measured values of UVB solar radiation varies from 1.2% to 2.8%. The effect of the annual cycles of solar zenith angle (SZA) and total column ozone (TCO) on the ratios (EER/G) are presented and the correction factors are determined for removal of the ozone cycle. The seasonal variability of EER/G is also discussed. The effect of the annual cycles of solar zenith angle (SZA) and total column ozone (TCO) on the ratios (EER/G) is presented and the correction factors are determined for removal of the ozone cycle. 相似文献
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以宝鸡渭河南部台塬区生态建设规划为例,对城市郊区村庄依据区位条件和建设条件进行划分,提出了郊区型村庄基础设施建设的普遍原则,分析探讨了不同类型村庄基础设施建设中存在问题和解决问题的对策。 相似文献
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航站楼行李提取大厅是机场旅客最集中的重要区域之一,大厅的面积直接关系到航站楼空间资源配置、整体运行成本以及旅客服务水平,因此做好该区域面积规划尤为重要。然而,目前航站楼功能区面积确定方法过于粗糙和保守,并且忽略了旅客到达分布特性和服务设施利用的时间性。本方法借助旅客流和行李流累计到达概率分布曲线,通过引入停留时间的概念,将时间融入到空间需求中,实现了行李提取区面积优化。 相似文献
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Huihui Feng Xiaofeng Zhao Feng Chen Lichun Wu 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2014
This paper proposed a quantitative method of land use change trajectory, which means the succession among different land use types across time, to examine the effects of urbanization on an urban heat island (UHI). To accomplish this, multi-temporal images from Landsat 5 Thematic Mapper (TM) and Landsat 7 Enhanced Thematic Mapper Plus (ETM+) of Xiamen City in China from 1987 to 2007 were selected. First, the land use change trajectories were extracted based on the classified images from different years. Then the land surface temperatures (LST) were retrieved and the magnitudes of the UHI were evaluated using the UHI intensity (UHII) indicator. Finally, the indices of the contribution to UHI intensity (CUHII) were constructed and calculated to quantify the effects of each land use change trajectory on the UHI during urbanization. The results demonstrated that the land use change trajectories and CUHII are effective and useful in quantifying the effects of urbanization on UHI. In Xiamen City, a total of 2218 land use change trajectories were identified and 530 of them were the existing urban or urbanization trajectories. The UHII presents a trend of continuous increase from 0.83 °C in 1987 to 2.14 °C in 2007. With respect to the effects of urban growth on UHI, the contribution of existing urban area to UHI decreased during urbanization. Prior to 2007, the existing urban area of trajectory NO. 44444 had the most significant effect on UHI with the greatest CUHII, while the value has decreased from 55.00% in 1987 to 13.03% in 2007 because of the addition of new urbanized area. In 2007, the greatest CUHII was replaced by a trajectory from farmland to built-up area (NO. 22224) with the CUHII of 21.98%, followed by the existing urban area of trajectory NO. 44444 with the CUHII of 13.03%. These results provide not only a new methodology to assess the environmental effects of urbanization, but also decision-supports for the planning and management of cities. 相似文献
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Rita Pongracz Judit Bartholy Zsuzsanna Dezso 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2006,37(12):2191-II
Urban heat island (UHI) effects on the ten most populated cities of Hungary, including the Budapest agglomeration area, were analyzed using remotely sensed data. Day- and night-time surface temperature time series observed by sensor MODIS on satellite Terra were used to determine UHI intensities. UHI intensity was defined as the difference in spatially averaged surface temperatures between urban and surrounding rural pixels. Spatial structures of UHIs were determined and compared for different seasons and macrocirculation conditions. 相似文献
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运用文献资料法,深入剖析陕西申办全运会的条件优势,阐述陕西申办全运会与西安城市经济现代化、基础建设现代化、旅游业现代化和城市文明现代化的互动,提出了陕西省申办全运会的策略。 相似文献