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991.
This research presents an intelligent planning support system based on multi-agent systems for spatial urban land use planning. The proposed system consists of two main phases: a pre-negotiation phase and an automated negotiation phase. The pre-negotiation phase involves interaction between human actors and intelligent software agents in order to elicit the actors’ social preferences. The agents employ social value orientation theory, which is rooted in social psychology, in order to model actors’ social preferences. The automated negotiation phase involves negotiation among autonomous software agents, the aim being to achieve consensus about the spatial problem on behalf of the relevant actors and using the information obtained.

This study employs a computationally effective Bayesian learning technique, along with social value orientation theory, to design socially rational intelligent agents who work on behalf of real actors. The proposed system is applied to a real world urban land use planning case study. Human actors participate in a pre-negotiation phase, and their social preferences are elicited by intelligent software agents through a number of interactions. Then, software agents come together to engage in an automated negotiation phase and eventually reach an agreement on the spatial configuration of urban land uses on behalf of the actors. The results of the study show that the proposed system is effective at performing an automated negotiation, plus that the final plan – which is the output of the automated negotiation – produces higher social utility and better spatial land use configurations for the agents.  相似文献   

992.
遥感影像中混合像元普遍存在。端元固定的情况下对混合像元进行分解,很难高精度地识别影像地物。本文基于支持向量机,提出了端元可变的非线性混合像元分解模型。首先,通过构建多个支持向量机获取每个像元的优化端元集,在优化端元集的基础上运用支持向量机与两两配对方法相结合的算法获取像元组分。试验结果表明,本文提出的方法效果优于传统的多端元光谱分解法。  相似文献   
993.
针对基于高斯径向基核函数的OCSVM等异常检测算法,对地物光谱变异极为敏感,导致算法异常检测性能不稳定的问题,根据光谱角度余弦测度对光谱形状相似性的描述不受地物光谱辐射强度变异影响的特性,将具有非正定核特性的光谱角度余弦核测度引入非正定SVM算法中,提出一种基于非正定OCSVM的高光谱影像地物异常检测算法。利用四组模拟数据进行目标异常检测实验,结果表明,该算法能够有效检测出高光谱影像数据中的目标地物,检测精度提升明显。  相似文献   
994.
在支持向量机的预测模型中,关键参数的选取是最重要的一步。在此基础上提出基于AEPSO改进的支持向量机预测模型。利用AEPSO的局部和全局搜索能力,提高支持向量机关键参数寻优的精度。文中详细介绍模型建立的过程,以莆田市木兰溪防洪工程为例,应用改进的模型进行堤基沉降预测,并与标准PSO支持向量机预测模型相对比。结果表明,基于AEPSO改进的支持向量机预测模型提高了预测的精度。  相似文献   
995.
谌伟 《测绘工程》2016,25(11):38-42
为达到提高滑坡变形预测精度的目的,利用量子算法和粒子群算法对支持向量机进行优化,并利用马尔科夫链对滑坡变形预测误差进行修正,综合构建滑坡变形的递进式预测模型。结果表明:通过量子算法及粒子群算法对支持向量机优化,克服支持向量机参数选取困难,实现预测过程的全局优化,并经过MC误差修正模型对滑坡变形预测值误差修正,提高预测精度及预测值稳定性,验证预测模型可行性和有效性,为滑坡变形预测提供一种新的预测方法。  相似文献   
996.
Modern hyperspectral imaging and non-imaging spectroradiometer has the capability to acquire high-resolution spectral reflectance data required for surface materials identification and mapping. Spectral similarity metrics, due to their mathematical simplicity and insensitiveness to the number of reference labelled spectra, have been increasingly used for material mapping by labelling reflectance spectra in hyperspectral data labelling. For a particular hyperspectral data set, the accuracy of spectral labelling depends considerably upon the degree of unambiguous spectral matching achieved by the spectral similarity metric used. In this work, we propose a new methodology for quantifying spectral similarity for hyperspectral data labelling for surface materials identification. Developed adopting the multiple classifier system architecture, the proposed methodology unifies into a single framework the differential performances of eight different spectral similarity metrics for the quantification of spectral matching for surface materials. The proposed methodology has been implemented on two types of hyperspectral data viz. image (airborne hyperspectral images) and non-image (library spectra) for numerous surface materials identification. Further, the performance of the proposed methodology has been compared with the support vector machines (SVM) approach, and with all the base spectral similarity metrics. The results indicate that, for the hyperspectral images, the performance of the proposed methodology is comparable with that of the SVM. For the library spectra, the proposed methodology shows a consistently higher (increase of about 30% when compared to SVM) classification accuracy. The proposed methodology has the potential to serve as a general library search method for materials identification using hyperspectral data.  相似文献   
997.
结合极化分解特征的SVM溢油检测研究   总被引:1,自引:1,他引:0  
Marine oil spills have caused major threats to marine environment over the past few years.The early detection of the oil spill is of great significance for the prevention and control of marine disasters.At present,remote sensing is one of the major approaches for monitoring the oil spill.Full polarization synthetic aperture radarc SAR data are employed to extract polarization decomposition parameters including entropy(H) and reflection entropy(A).The characteristic spectrum of the entropy and reflection entropy combination has analyzed and the polarization characteristic spectrum of the oil spill has developed to support remote sensing of the oil spill.The findings show that the information extracted from(1–A)×(1–H) and(1–H)×A parameters is relatively evident effects.The results of extraction of the oil spill information based on H×A parameter are relatively not good.The combination of the two has something to do with H and A values.In general,when H0.7,A value is relatively small.Here,the extraction of the oil spill information using(1–A)×(1–H) and(1–H)×A parameters obtains evident effects.Whichever combined parameter is adopted,oil well data would cause certain false alarm to the extraction of the oil spill information.In particular the false alarm of the extracted oil spill information based on(1–A)×(1–H) is relatively high,while the false alarm based on(1–A)×H and(1–H)×A parameters is relatively small,but an image noise is relatively big.The oil spill detection employing polarization characteristic spectrum support vector machine can effectively identify the oil spill information with more accuracy than that of the detection method based on single polarization feature.  相似文献   
998.
全极化SAR获取的信息量远多于传统SAR,但信息量的增加并不能确保分类精度的提高,如何有效进行特征选择至关重要。针对自适应特征选择问题,提出一种顾及分类器参数的特征选择和分类方法。该方法以支持向量数为评估依据,结合遗传算法进行特征选择,并同时对分类器参数进行寻优;最后利用优选的特征集和模型参数进行分类。为验证算法的有效性,利用两组全极化数据进行了监督分类实验。实验结果表明,提出方法降低了SVM分类器对自身参数的敏感性,而且能在较少特征个数下具备良好的泛化性能,分类精度优于未经过特征选择和参数优化的方法。  相似文献   
999.
为了提高洪水过程的非线性拟合能力和预报精度,对支持向量机洪水预报模型进行了深入研究。针对鸭绿江流域临江站的实际情况,建立了临江站洪水过程ν-SVR预报模型,采用1998~2014年间的大水年份降水资料和洪水过程资料对ν-SVR预报模型进行了率定和验证,并与线性动态系统模型、BP人工神经网络模型和ε-SVR模型进行了比较。结果表明:ν-SVR洪水预报模型比线性动态系统模型和BP人工神经网络具有较高的精度。ν-SVR洪水预报模型具有较好的非线性拟合能力和泛化能力,能很好地控制支持向量个数、降低模型的复杂程度,同时能保持良好的预报精度。  相似文献   
1000.
杨伟  梁英英  王振福 《探矿工程》2016,43(10):92-95
吴起县居宁花园后侧山体存在高陡黄土边坡,在长期降雨及人类工程活动的影响下,形成了崩塌地质灾害隐患。对此,提出了采用削方减载和土钉支护加强坡体稳定性的组合治理方案,并结合治理区实际情况,对分级削坡和土钉支护的各项参数、工艺要求、施工方法等进行了设计。按照设计方案施工结束后,坡体得到了有效加固,达到了治理的目的。  相似文献   
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