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介绍一种稀疏的贝叶斯学习算法——关联向量机(RVM),它在再生核希尔伯特空间中学习,利用贝叶斯方法推理,推广能力好,与支持向量机相比不仅解更为稀疏而且不需要调整超参数。应用RVM的对小样本的良好分类能力,提出一种基于RVM的入侵检测原型系统。 相似文献
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郑州市区的地下热水来自增温地层,在使用电法勘探确定热水层位和埋深时,用五极纵轴测深法与对称四极测深法相结合,取得了良好的地质效果。 相似文献
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Ruifeng Ding 《International journal of geographical information science》2018,32(8):1631-1648
How to exploit various features of users and points of interest (POIs) for accurate POI recommendation is important in location-based social networks (LBSNs). In this paper, a novel POI recommendation framework, named RecNet, is proposed, which is developed based on a deep neural network (DNN) to incorporate various features in LBSNs and learn their joint influence on user behavior. More specifically, co-visiting, geographical and categorical influences in LBSNs are exploited to alleviate the data sparsity issue in POI recommendation and are converted to feature vector representations of POIs and users via feature embedding. Moreover, the embedded POIs and users are fed into a DNN pairwise to adaptively learn high-order interactions between features. Our method is evaluated on two publicly available LBSNs datasets and experimental results show that RecNet outperforms state-of-the-art algorithms for POI recommendation. 相似文献
979.
Mining transition rules of cellular automata for simulating urban expansion by using the deep learning techniques 总被引:3,自引:0,他引:3
Jialv He Yao Yao Ye Hong Zhang Jinbao 《International journal of geographical information science》2018,32(10):2076-2097
Along with the gradually accelerated urbanization process, simulating and predicting the future pattern of the city is of great importance to the prediction and prevention of some environmental, economic and urban issues. Previous studies have generally integrated traditional machine learning with cellular automaton (CA) models to simulate urban development. Nevertheless, difficulties still exist in the process of obtaining more accurate results with CA models; such difficulties are mainly due to the insufficient consideration of neighborhood effects during urban transition rule mining. In this paper, we used an effective deep learning method, named convolution neural network for united mining (UMCNN), to solve the problem. UMCNN has substantial potential to get neighborhood information from its receptive field. Thus, a novel CA model coupled with UMCNN and Markov chain was designed to improve the performance of simulating urban expansion processes. Choosing the Pearl River Delta of China as the study area, we excavate the driving factors and the transformational relations revealed by the urban land-use patterns in 2000, 2005 and 2010 and further simulate the urban expansion status in 2020 and 2030. Additionally, three traditional machine-learning-based CA models (LR, ANN and RFA) are built to attest the practicality of the proposed model. In the comparison, the proposed method reaches the highest simulation accuracy and landscape index similarity. The predicted urban expansion results reveal that the economy will continue to be the primary factor in the study area from 2010 to 2030. The proposed model can serve as guidance in urban planning and government decision-making. 相似文献
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Salient, long-term solutions to address global environmental change hinge on management strategies that are inclusive of local voices and that recognize the array of values held by surrounding communities. Group-based participatory processes that involve deliberation of multiple stakeholders with varying perspectives—particularly social learning—hold promise to advance inclusive conservation by identifying and creating a shared understanding of the landscape. However, few studies have empirically investigated how the value basis of stakeholder deliberation changes over time in relation to social learning. This study provided a novel platform for local stakeholders from Interior Alaska to deliberate on landscape change and associated management practices in ways that shifted their value orientations. In particular, we used a pre-test, post-test experimental design involving mixed methods to measure how different types of values changed as a result of social learning through an online discussion forum. We found evidence that social learning: 1) activated shared values that were previously hidden through building a relational understanding of others, and 2) shifted values that spanned three levels of psychological stability. As hypothesized, social values that represented expressed preferences for landscape change were most likely to shift in association with social learning. Conversely, shifts in individual values towards self-transcendence required learning to go beyond the discussion forum and be situated within the participants’ broader communities of practice. Overall, this longitudinal study highlights how social learning facilitated through deliberation presents opportunities to identify shared values and spark value shifts across stakeholder groups, thus incorporating diverse viewpoints into decision-making about global environmental change. 相似文献