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91.
浅层地震作为城市地下空间探测中必不可少的一种手段,其勘探效果受到很多方面的影响,如激发、接收因素、采集参数以及处理方法等,因此需要根据地质任务进行系统科学的论证、选取.笔者以济南地下空间探测项目为例,探讨提高浅层地震勘探分辨率的方法,通过综合分析研究区的资料建立合理的地震地质模型,基于该模型进行地震采集参数波动方程正演...  相似文献   
92.
区域创新政策对创新驱动增长和经济结构转型升级至关重要。20世纪90年代以来,基于对新古典主义经济学“空间中性”的创新政策的反思,欧洲经济地理学提出“基于空间”的区域创新政策,至今已被欧盟委员会和经济合作与发展组织等组织所采用。本文对这一时期欧洲经济地理学区域创新政策的发展背景、主要任务、理论基础和政策建议等方面进行梳理,研究发现:第一,欧洲经济地理学区域创新政策的主流框架有3个,分别是区域创新系统、精明专业化和可持续转型地理理论;第二,3个框架各有侧重,区域创新系统侧重解决系统失灵问题,精明专业化聚焦优先发展领域的选择问题,可持续转型地理理论则强调转型失灵问题;第三,针对上述问题,3个框架均给出“基于空间”的区域创新政策建议,其中,区域创新系统和精明专业化是基于区域资源禀赋差异的视角,可持续转型地理理论则从技术的空间粘性角度出发。最后,提出中国经济地理学未来区域创新政策研究的几个重点研究方向。  相似文献   
93.
从智慧城市的概念和发展历程出发,提出数字城市、物联网、云计算等智慧城市建设的关键技术,探讨了高分辨率对地观测技术在智慧城市建设中的应用,列举了智慧城市的典型应用,指出了从数字城市发展到智慧城市的必然趋势,并展望智慧城市的挑战和美好前景。  相似文献   
94.
ABSTRACT

Relocating people in informal settlements and upgrading the lives of those people require consistent commitment, good strategies, and supporting systems. In South Africa, in order to allocate subsidized housing to beneficiaries of an informal settlement, beneficiary administration needs to determine the number of people who qualify for subsidized houses. Without geo-spatial data-based technical verification, conventional methods of occupancy audits are often cumbersome, are unreliable, and do not promote smart and evidence-based decision making. Accordingly, the aim of this study is to propose and develop an Oracle-based mobile GIS tool to conduct an occupancy audit for Ulana, an informal settlement in Ekurhuleni Municipality in South Africa. Android-based tablets were used to collect the geographic and socio-economic attributes of the informal dwelling units (DU). Spatial analysis (in ArcGIS software and geo-spatial modeling environment) and statistical analysis were conducted to produce the occupancy audit. The results indicated that the use of mobile GIS provides up-to-date, accurate, comprehensive, and real-time data so as to facilitate the development of smart and integrated human settlements. The results of this audit also indicated that only 57% of the households residing in Ulana could potentially benefit from receiving a subsidized house. Accordingly, the occupancy audit enables planners to plan appropriate upgrading and housing development strategies for informal settlement. This study demonstrates that successful planning of housing delivery for post independent integrated neighborhoods is not a mere political rhetoric but is viable when it is based on reasonable geo-spatial techniques and information. The use of mobile GIS therefore needs to be extended to other informal settlement upgrading projects in South Africa as well as other cities in the global south. However, proper professional training is required to ensure the successful usage of smart mobile GIS tools.  相似文献   
95.
A clear understanding of the relationship between development patterns and municipal expenditures is complicated by how one chooses to quantify these patterns. Extant literature often employs a single density measure to capture the low-density nature of sprawl. While density provides an intuitive link to economies of scale and congestion costs, it fails to capture other spatial characteristics of sprawl related to centrality, connectedness, and mixed use that may influence municipal expenditures according to Smart Growth and New Urbanism advocates. This study uses Massachusetts orthoimagery data to construct multidimensional measures of residential and commercial land use patterns. Municipal expenditures associated with public works, fire, and police are regressed on multidimensional measures of land use as well as a number of demand controls. Findings indicate that economies and diseconomies do exist with respect to the multidimensional metrics considered. Support is mixed for development patterns emphasized by Smart Growth and New Urbanism advocates.  相似文献   
96.
Central to the Smart Growth movement is that compact development reduces vehicle miles traveled, carbon emissions, and water use. Empirical efforts to evaluate compact development have examined residential densities but have not distinguished decreasing lot sizes from multifamily apartments as mechanisms for compact development. Efforts to link design features to water use have emphasized single-family at the expense of multifamily housing. This study isolates the determinants of water use in large (more than fifty units) apartment complexes in the city of Tempe, Arizona. In July 2007, per bedroom water use increased with pool area, dishwashers, and in-unit laundry facilities. We are able to explain nearly 50 percent of the variation in water demand with these variables. These results inform public policy for reducing water use in multifamily housing structures, suggesting strategies to construct and market “green” apartment units.  相似文献   
97.
Complexities inherent to large‐scale modern civil structures pose many challenges in the design of feedback structural control systems for dynamic response mitigation. With the emergence of low‐cost sensors and control devices creating technologies from which large‐scale structural control systems can deploy, a future control system may contain hundreds, or even thousands, of such devices. Key issues in such large‐scale structural control systems include reduced system reliability, increasing communication requirements, and longer latencies in the feedback loop. To effectively address these issues, decentralized control strategies provide promising solutions that allow control systems to operate at high nodal counts. This paper examines the feasibility of designing a decentralized controller that minimizes the ?? norm of the closed‐loop system. ?? control is a natural choice for decentralization because imposition of decentralized architectures is easy to achieve when posing the controller design using linear matrix inequalities. Decentralized control solutions are investigated for both continuous‐time and discrete‐time ?? formulations. Numerical simulation results using a 3‐story and a 20‐story structure illustrate the feasibility of the different decentralized control strategies. The results also demonstrate that when realistic semi‐active control devices are used in combination with the decentralized ?? control solution, better performance can be gained over the passive control cases. It is shown that decentralized control strategies may provide equivalent or better control performance, given that their centralized counterparts could suffer from longer sampling periods due to communication and computation constraints. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
98.
顾建祥 《现代测绘》2012,35(2):13-15
本文以地理信息公共服务在智慧消防中的应用为主线,在研究智能化消防和地理信息公共服务平台特点的基础上,采用地图服务融合的方式,从地理服务接入、城市三维模型、室内三维模型消防应用、智能感应位置服务等多个方面入手,深入探讨地理信息服务服务于智能化消防平台应用的关键技术,实现消防业务的三维智能化管理.  相似文献   
99.
通过综合分析张马屯铁矿尾矿基本特性,对张马屯铁矿尾矿进行了铁尾矿砖生产试验研究。结果表明,利用张马屯铁矿尾矿,采用压制成型法,可以制备出MU10等级以上的建筑用砖,颜色一致性好,铁尾矿砖为灰色,抗冻性良好。认为利用尾矿制备建筑用砖是一条很好的尾矿利用途径,具有明显的经济效益和广泛的应用前景。  相似文献   
100.
孔宇  甄峰  张姗琪 《地理科学进展》2022,41(6):1068-1081
智能技术的影响已经渗透到城市的不同方面,空间要素的流动更快更复杂,城市功能需要进行调整以适应居民活动的变化,城市空间的智能化发展与运营管理也成为新的挑战。论文从城市空间要素组织、居民活动与空间功能、空间运营管理3个方面梳理当前智能技术对城市空间的影响,并展望未来5~10 a的城市空间应具有瞬时异地、空间智能化、复杂流动性以及韧性能力更强的特点,最后从城市空间组织、功能形态、运营管理与规划方法4个方面探讨了未来的城市空间研究需要关注的重点内容,以期为智能技术影响下的城市空间研究与规划设计提供参考。  相似文献   
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