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1.
城市扩展元胞自动机多结构卷积神经网络模型   总被引:2,自引:0,他引:2  
传统的城市扩展元胞自动机(CA)模型是基于单个元胞的变量信息挖掘来构建转换规则的。针对这一问题,本文基于多结构卷积神经网络提出从区域特征出发且顾及区域多尺度特征挖掘转换规则的城市扩展元胞自动机模型(MSCNN-CA),并以武汉主城区和上海浦东新区为例,模拟了两个试验区2005—2015年期间城市扩展过程。模型验证表明:与逻辑回归和神经网络相比,本文构建的3个单一结构的卷积神经网络元胞自动机(CNN-CA)模型在4个指标(Kappa系数、FoM(figure of merit)值、命中率(h)和错误率(m))上都有不同程度的提高。特别是FoM指数,在武汉主城区提高了23.3%~29.4%,在上海浦东新区提高了20.3%~28.5%。此外,MSCNN-CA模型与3个单一结构的CNN-CA模型相比,在各个指标上也有所改善,FoM指数在武汉主城区提高了0.8%~4.8%,上海浦东新区提高了2.8%~7.8%。两个试验区的模拟结果表明:相比传统CA模型,基于多结构卷积神经网络的城市扩展元胞自动机模型(MSCNN-CA)能够有效提高城市扩展模拟的精度,更真实地反映城市扩展空间演变过程。相比单结构的卷积神经网络CA模型,多结构卷积神经网络CA模型的稳定性和模拟结果准确性有所提升。  相似文献   

2.
元胞自动机模型在土地扩展的转换规则设计上具有随机性,受周围环境影响较大。文中建立基于BP神经网络和遗传神经网络算法优化的元胞自动机土地扩张模型,对广州市2009—2011年进行城市扩张模拟分析。实验结果显示:BP神经网络能够较好地模拟分布较集中的耕地和林地等区域,精度可达到70%以上,而对于面积较零碎的建筑用地区域,模拟效果较差;而遗传神经网络优化算法能够总体提高模拟精度约5%,部分精度能提高至20%。同时,该算法还能充分考虑影响土地变化的各种扰动因素,优化选择驱动因子和缩短迭代次数,对于城市土地扩张研究具有可行性。  相似文献   

3.
提出了一种基于生物地理学优化算法寻找城市扩展元胞自动机(cellular automata,CA)模型最佳参数的方法。转换规则制定及相应权重参数获取是构建城市扩展CA的核心和难点。生物地理学优化算法(biogeography-based optimization,BBO)通过模拟生物物种在栖息地的分布、迁移和灭绝来求解优化问题。利用BBO算法自动获取城市扩展CA模型参数值,构建BBO-CA模型进行城市扩展模拟实验,并与粒子群算法(particle swarm optimization,PSO)、蚁群算法(ant colony optimization,ACO)、遗传算法(genetic algorithm,GA)及逻辑回归(logistic regression,LR)等方法相比较。结果表明,BBO算法具有较好的收敛性,可有效地快速自动寻找城市扩展CA模型最佳参数组合,获取的空间变量权重参数较为合理;BBO-CA模型明显提升了城市用地模拟精度,城市用地模拟精度为72.5%,相对PSO、ACO、GA、LR各算法分别提升了1.1%、1.2%、2.7%和4.0%,Kappa系数达到0.700,分别提升了0.015、0.016、0.034和0.046,且整体空间布局与实际情况更为接近,验证了应用BBO算法的可行性与优势。  相似文献   

4.
预测及模拟城市朋地的动态变化,可以为城市空间整合及可持续发展等相关政策的制定提供科学依据.利用基于BP神经网络的元胞自动机模型,对2005-2010年间萝岗区城市用地的扩展进行空间模拟,并预测未来5年的萝岗区城市扩张的空间分布,评价其合理性,为规划制定合理的土地政策和城市总体规划提供科学的决策依据.  相似文献   

5.
为找出无人机实测数据高程转换拟合的方法,本文基于不同激活函数激活极限学习机模型得到ELMS、ELMR、ELMH3种模型,并将计算结果与广义回归神经网络模型和BP神经网络模型对比,结果表明:基于5种模型可对无人机实测高程数据的异常点进行筛选并剔除,3种ELM模型对于高程点的筛选结果基本一致,共筛选出了21个高程异常点,GRNN模型精度次之,BP神经网络模型精度最低,ELM模型在不同激活函数下的计算精度有所不同,其中ELMS模型在高程点剔除和高程数据拟合中精度最高,RMSE仅为0.157m,而Ens和R2分别达到了0.944和0.968,可为无人机实测数据高程转换拟合的标准模型使用。  相似文献   

6.
多光谱影像记录了地球上各类地物的电磁波,具有极大的信息量,对影像上相关信息的处理和提取是遥感信息应用的前提。多光谱影像的信息自动提取技术的准确性和提取速度是图像分析与理解领域永恒的研究主题。针对遥感影像信息提取的复杂性和极限学习机ELM的分类性能,在单隐层神经网络和极限学习机理论的基础上,提出了基于粒子群参数寻优的混合核函数极限学习机分类模型。与标准的ELM、支持向量机等分类模型进行比较验证,实验结果表明,混合核函数的极限学习机总体分类精度最高,达到了92.67%,有效提高了影像信息提取的精度和速度,很好地满足了图像信息自动提取对准确率和速度的双重要求。  相似文献   

7.
对城市建成区扩展的预测是防止城市蔓延的重要管理依据。目前,元胞自动机-马尔可夫链模型,已成为城市建成区扩展预测的重要方法。该模型对指标权重的赋值方法较为敏感,以往的单一指标赋值法,影响了城市建成区扩展预测的精度和可信度。为此,本研究提出整合传统权重赋值法的AHP和逻辑回归模型改进CA-Markov模型。研究选择云南省大理市为案例,对2020、2030年的城市建成区扩展进行模拟和预测,最后进行精度验证。研究结果表明:①Kappa指数可达到96.8%,预测结果有较好的一致性。②大理市的城市建成区扩展均表现为继续向外扩展,以东南、西北方向和两片建成区之间为主要扩展方向。研究提供了组合权重赋值法改进CA-Markov模型,这将为规划者在未来规划中提供强有力的支持。  相似文献   

8.
基于SLEUTH模型的长江口北岸土地利用演化模拟研究   总被引:2,自引:0,他引:2  
采用经典的元胞自动机城市扩展与土地利用演化SLEUTH模型,改进元胞自动机控制系数的筛选方法,结合驱动力的研究调整模型控制系数,根据长江口北岸流域实际情况设置模型校准参数,提高模型在长江口北岸流域应用的实用性。研究表明SLEUTH模型方法可以获得精度较高的土地利用变化模拟结果。  相似文献   

9.
针对目前的地铁隧道沉降变形预测方法忽略了对沉降变形影响因素的综合协调考虑这一问题,该文将遗传算法(GA)结合极限学习机(ELM)的方法引入地铁隧道沉降变形预测。该方法借助最大信息熵理论,充分挖掘地铁隧道沉降主要影响因素与沉降量间的信息特征,并将遗传算法与极限学习机相耦合,利用遗传算法的全局搜索能力获取ELM神经网络优化的初始权值和阈值,形成熵权遗传算法-极限学习机模型,并编制相应计算程序。采用该模型对西安某地铁隧道沉降变形进行预测,并与遗传算法-极限学习机、极限学习机、传统的BP神经网络预测结果进行比较,结果表明熵权遗传算法-极限学习机模型与实测值吻合更好,预测结果更稳定。  相似文献   

10.
本文提出了一种基于粒子群算法来自动获取矢量元胞自动机转换规则的新方法。采用粒子群算法所提取的转换规则毋需通过数学公式来表达,能更方便和准确地描述自然界中的复杂关系,并且这些规则比数学公式更容易让人理解。以丹阳市城市扩展为例,使用粒子群算法挖掘元胞自动机转换规则模拟该研究区域的城市扩展过程,并对模拟结果进行了精度评价。  相似文献   

11.
利用结构自适应极端学习机预报导航卫星钟差   总被引:1,自引:0,他引:1       下载免费PDF全文
针对卫星钟差难以用精确模型来进行预报的问题,将极端学习机(extreme learning machine,ELM)神经网络用于导航卫星钟差预报。针对ELM网络隐层结构难以确定的问题,提出了基于自适应共振理论(adaptive resonance theory,ART)网络思想的ELM网络结构设计算法。该算法将ART网络的聚类特性用于ELM网络结构设计中,通过对输入向量与已存模式的相似度比较将输入向量进行分类,自适应地确定隐层节点规模。使用GPS卫星钟差数据进行30 d的预报实验,结果表明,此方法的钟差预报精度明显优于二次多项式模型和灰色系统模型。  相似文献   

12.
贝叶斯极限学习机(BELM)具有充分利用数据先验信息,可以自适应估计模型参数的特点。但在样本数量不断增加时,如果每次都对BELM重新训练将会降低计算效率。针对此问题,本文提出一种动态贝叶斯极限学习机(DBELM)方法以应用于变形监测数据实时预报。该方法以BELM训练的模型参数为初值,根据新增样本信息可对初始模型参数进行动态更新,并从理论上推导了相关计算公式。通过对仿真数据和实际变形数据进行详细分析表明:DBELM方法的预报精度要优于BELM、正则化极限学习机(RELM)、极限学习机(ELM)3种方法。特别是在长期持续预报过程中,其预报性能相对于其余3种方法优势明显。这充分表明了所提方法应用于变形监测数据预报领域具有可行性和有效性。  相似文献   

13.
The main objective of this paper is to analyze urban sprawl in the metropolitan city of Tripoli, Libya. Logistic regression model is used in modeling urban expansion patterns, and in investigating the relationship between urban sprawl and various driving forces. The 11 factors that influence urban sprawl occurrence used in this research are the distances to main active economic centers, to a central business district, to the nearest urbanized area, to educational area, to roads, and to urbanized areas; easting and northing coordinates; slope; restricted area; and population density. These factors were extracted from various existing maps and remotely sensed data. Subsequently, logistic regression coefficient of each factor is computed in the calibration phase using data from 1984 to 2002. Additionally, data from 2002 to 2010 were used in the validation. The validation of the logistic regression model was conducted using the relative operating characteristic (ROC) method. The validation result indicated 0.86 accuracy rate. Finally, the urban sprawl probability map was generated to estimate six scenarios of urban patterns for 2020 and 2025. The results indicated that the logistic regression model is effective in explaining urban expansion driving factors, their behaviors, and urban pattern formation. The logistic regression model has limitations in temporal dynamic analysis used in urban analysis studies. Thus, an integration of the logistic regression model with estimation and allocation techniques can be used to estimate and to locate urban land demands for a deeper understanding of future urban patterns.  相似文献   

14.
In recent years, the rapid expansion of urban spaces has accelerated the mutual evolution of landscape types. Analyzing and simulating spatio-temporal dynamic features of urban landscape can help to reveal its driving mechanisms and facilitate reasonable planning of urban land resources. The purpose of this study was to design a hybrid cellular automata model to simulate dynamic change in urban landscapes. The model consists of four parts: a geospatial partition, a Markov chain (MC), a multi-layer perceptron artificial neural network (MLP-ANN), and cellular automata (CA). This study employed multivariate land use data for the period 2000–2015 to conduct spatial clustering for the Ganjingzi District and to simulate landscape status evolution via a divisional composite cellular automaton model. During the period of 2000–2015, construction land and forest land areas in Ganjingzi District increased by 19.43% and 15.19%, respectively, whereas farmland, garden lands, and other land areas decreased by 43.42%, 52.14%, and 75.97%, respectively. Land use conversion potentials in different sub-regions show different characteristics in space. The overall land-change prediction accuracy for the subarea-composite model is 3% higher than that of the non-partitioned model, and misses are reduced by 3.1%. Therefore, by integrating geospatial zoning and the MLP-ANN hybrid method, the land type conversion rules of different zonings can be obtained, allowing for more effective simulations of future urban land use change. The hybrid cellular automata model developed here will provide a reference for urban planning and policy formulation.  相似文献   

15.
Based on remote sensing and GIS, this study models the spatial variations of urban growth patterns with a logistic geographically weighted regression (GWR) technique. Through a case study of Springfield, Missouri, the research employs both global and local logistic regression to model the probability of urban land expansion against a set of spatial and socioeconomic variables. The logistic GWR model significantly improves the global logistic regression model in three ways: (1) the local model has higher PCP (percentage correctly predicted) than the global model; (2) the local model has a smaller residual than the global model; and (3) residuals of the local model have less spatial dependence. More importantly, the local estimates of parameters enable us to investigate spatial variations in the influences of driving factors on urban growth. Based on parameter estimates of logistic GWR and using the inverse distance weighted (IDW) interpolation method, we generate a set of parameter surfaces to reveal the spatial variations of urban land expansion. The geographically weighted local analysis correctly reveals that urban growth in Springfield, Missouri is more a result of infrastructure construction, and an urban sprawl trend is observed from 1992 to 2005.  相似文献   

16.
A new machine learning paradigm for terrain reconstruction   总被引:1,自引:0,他引:1  
Terrain models that permit multiresolution access are essential for model predictive control of unmanned aerial vehicles in low-level flights. The authors present the extreme learning machine (ELM), a recently proposed learning paradigm, as a mechanism for learning the stored digital elevation information to allow multiresolution access. We give results of simulations designed to compare the performance of our approach with two other approaches for multiresolution access, namely: 1) linear interpolation on Delaunay triangles of the sampled terrain data points and 2) terrain learning using support vector machines (SVMs). The results show that to achieve the same mean square error during access, the memory needed in our approach is significantly lower. Additionally, the offline training time for the ELM network is much less than that for the SVM.  相似文献   

17.
针对大坝变形监测数据中存在的非线性关系强和传统大坝预测模型精度不高等问题,本文利用改进蝙蝠算法选取最优的参数作为极限学习机的连接权值和阈值,并提出了一种基于改进蝙蝠算法(IBA)优化极限学习机(ELM)的大坝变形预测模型(IBA-ELM)。将IBA-ELM模型应用于工程实例,通过对某地水库大坝监测数据预测分析,验证IBA-ELM模型、BA-ELM和GA-ELM模型预测结果并进行精度评价,3种模型的预测值与实测值平均绝对误差分别为1.178 3、0.459 8、0.335 6 mm,IBA-ELM模型的预测精度高于另外2种模型,表明IBA-ELM模型能有效提高大坝变形预测能力。  相似文献   

18.
This paper presents a new type of cellular automata (CA) model for the simulation of alternative land development using neural networks for urban planning. CA models can be regarded as a planning tool because they can generate alternative urban growth. Alternative development patterns can be formed by using different sets of parameter values in CA simulation. A critical issue is how to define parameter values for realistic and idealized simulation. This paper demonstrates that neural networks can simplify CA models but generate more plausible results. The simulation is based on a simple three-layer network with an output neuron to generate conversion probability. No transition rules are required for the simulation. Parameter values are automatically obtained from the training of network by using satellite remote sensing data. Original training data can be assessed and modified according to planning objectives. Alternative urban patterns can be easily formulated by using the modified training data sets rather than changing the model.  相似文献   

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