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101.
C. M. Almeida J. M. Gleriani E. F. Castejon B. S. Soares‐Filho 《International journal of geographical information science》2013,27(9):943-963
Empirical models designed to simulate and predict urban land‐use change in real situations are generally based on the utilization of statistical techniques to compute the land‐use change probabilities. In contrast to these methods, artificial neural networks arise as an alternative to assess such probabilities by means of non‐parametric approaches. This work introduces a simulation experiment on intra‐urban land‐use change in which a supervised back‐propagation neural network has been employed in the parameterization of several biophysical and infrastructure variables considered in the simulation model. The spatial land‐use transition probabilities estimated thereof feed a cellular automaton (CA) simulation model, based on stochastic transition rules. The model has been tested in a medium‐sized town in the Midwest of São Paulo State, Piracicaba. A series of simulation outputs for the case study town in the period 1985–1999 were generated, and statistical validation tests were then conducted for the best results, based on fuzzy similarity measures. 相似文献
102.
Kai Cao Michael Batty Bo Huang Yan Liu Le Yu Jiongfeng Chen 《International journal of geographical information science》2013,27(12):1949-1969
A spatial multi-objective land use optimization model defined by the acronym ‘NSGA-II-MOLU’ or the ‘non-dominated sorting genetic algorithm-II for multi-objective optimization of land use’ is proposed for searching for optimal land use scenarios which embrace multiple objectives and constraints extracted from the requirements of users, as well as providing support to the land use planning process. In this application, we took the MOLU model which was initially developed to integrate multiple objectives and coupled this with a revised version of the genetic algorithm NSGA-II which is based on specific crossover and mutation operators. The resulting NSGA-II-MOLU model is able to offer the possibility of efficiently searching over tens of thousands of solutions for trade-off sets which define non-dominated plans on the classical Pareto frontier. In this application, we chose the example of Tongzhou New Town, China, to demonstrate how the model could be employed to meet three conflicting objectives based on minimizing conversion costs, maximizing accessibility, and maximizing compatibilities between land uses. Our case study clearly shows the ability of the model to generate diversified land use planning scenarios which form the core of a land use planning support system. It also demonstrates the potential of the model to consider more complicated spatial objectives and variables with open-ended characteristics. The breakthroughs in spatial optimization that this model provides lead directly to other properties of the process in which further efficiencies in the process of optimization, more vivid visualizations, and more interactive planning support are possible. These form directions for future research. 相似文献
103.
典型喀斯特石漠化地区表土孢粉与现代植被关系 总被引:1,自引:1,他引:0
喀斯特石漠化地区6个不同植被类型的25个表土和苔藓样品的孢粉分析表明:(1)研究区植物孢粉共由47科属组成,以草本和蕨类植物占据优势,含量为23.62%~76.47%,其次是乔木[主要为马尾松(Pinus masso-niana)],含量为17.73%~74.05%,灌木植物花粉含量最低,为0~12.50%,显示该区植被退化严重;(2)研究区不同植被类型的表土孢粉组合差别明显,与其相应的实际植被情况大致相同,基本反映了石漠化地区现代植被的基本状况,表明孢粉可以为该区恢复和重建自然生态环境提供参考性依据。 相似文献
104.
高密度电法在柳州太阳村镇岩溶塌陷区调查中的应用研究 总被引:1,自引:0,他引:1
为了查明柳州太阳村镇岩溶塌陷形成的地质背景,本文采用高密度电法对该塌陷区进行调查研究。研究结果表明:高密度电法对于确定土层的厚度,区分土层和岩石的分界面具有较好的效果,通过电阻率的分布及变化趋势,可以较好的圈定地下岩溶裂隙带的发育位置,结合地质资料,对识别断裂破碎带也有较好的效果。三个塌陷区的致塌地质背景不尽相同:第Ⅰ,Ⅲ塌陷区塌陷的形成与人类活动密切相关,分别由机井抽水及输油管道铺设引发;第Ⅱ塌陷区塌陷的形成与自然因素相关,由断裂破碎带触发。通过高密度电法反演结果断面图,能较准确地查明塌陷的潜伏隐患区:第Ⅰ塌陷区的隐伏区为通过抽水井的近东西向的岩溶裂隙带,第Ⅱ塌陷区地质灾害的潜伏区为断层西侧的岩溶裂隙带,第Ⅲ塌陷区的隐患区为输油管道附近东侧的岩溶裂隙带,均位于人类活动频繁附近地段及构造发育带。 相似文献
105.
Ling Li 《中国地理科学(英文版)》1995,5(2):175-184
There are more women than men in Renhe Town, about 40% of women have jobs. Young women under 30 years old are mainly industrial
workers. The average years of education for all women over 6 years old are 6.03, but for man they are 7.64. The Women’s Federation
of Renhe Town is a vital organization. What it has done plays an active role in raising women/s social status and encouraging
women to take part in the community life. In the past, women mainly participated in different collective agricultural labour
assigned by their carders. Women had not much chance to show their intelligence and wisdom. Since the policy of ’ reform and
open door to the outside world’ was carried out women have had more and more chance to bring their abilities into full play
and many women become capable persons of different trades and professions. Now, in Renhe, women are the main force of factories
and dispensable part of all kinds of production work done in units of families. 相似文献
106.
107.
集镇体系与乡村市场网络研究──以山东省滕州市为例 总被引:2,自引:0,他引:2
乡村市场网络是乡村市场活动及各种市场流的地域组织形式,本文以滕州市为例研究了乡村市场网络的节点体系、组织结构、市场区域划分与线网体系,探讨了滕州市乡村市场网络基本特征,在此基础上对乡村市场网络的组织优化进行了初步的尝试,并提出了相应的优化建议。 相似文献
108.
基于RS和GIS技术下城镇空间变化分析及应用研究 总被引:16,自引:7,他引:16
城镇空间变化分析,是城镇发展趋势分析的基础,对城镇远景规划有十分重要的指导作用。它也是区域生态环境演变调控研究的重点内容和基础内容。本文将引用RS和GIS技术方法对城镇空间变化进行研究。其基本思路是,利用RS的TM卫片数据进行宏观监测,再利用GIS的空间分析功能,方便地进行城镇分布状况和迁移变化的空间分析与评价。该技术方法已被成功地应用于新疆城镇分布状况及动态变化研究项目中,收到较好效果。 相似文献
109.
AncientLoulanTOWnwasafamoustownontheSilkROadinthehistory,butsuddenlydisappearedfromthehistoricalrecords1400yearsago.Untilthespringof1900,Aierdeke,theUygurguideoftheexploringpartyledbyMr.SVehHedin,aSWedishexplorer,discoveredthismystery,whichmadeasensationintheworld.Afterwards,alotofexplorersathomeandabroad,E.NuntingtrnfromAmerica(1905),SirAureSteinfromEngland(1906,Igl4),azureOtanietal.fromJapan(1908--1911)wentthereoneafteranotherandthelastinvestigationofwidescopewasdonebyanarchaeologi… 相似文献
110.
Gustav Visser 《Geoforum》2003,34(1):123-137
In response to the current paucity of geographical research into post-apartheid development of gay leisure space, the paper focuses on the nature and extent of gay leisure space development in De Waterkant, South Africa’s first “gay village”, located in the Cape Town CBD periphery. Despite a new liberal constitutional environment, the gay spaces generated in post-apartheid De Waterkant are not inclusive of most gay South Africans. On the contrary, the legacy of apartheid race, gender and class inequality persists, generating a wealthy, White, male leisure space enclave. As a consequence, De Waterkant’s potential to function as a site of identity formation, development and re-affirmation, seen in many gay villages found in other Western societies, appears unlikely. 相似文献