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111.
The Bayesian network (BN) is a type of graphical network based on probabilistic inference that has been gradually applied to assessment of seismic liquefaction potential. However, how to construct a robust BN remains underexplored in this field. This paper aims to present an efficient hybrid approach combining domain knowledge and data to construct a BN that facilitates the integration of multiple factors and the quantification of uncertainties within a network model to assess seismic liquefaction. Initially, only using given domain knowledge, a naive network model can be constructed using interpretive structural modeling. Thereafter, some effective information about the naive model is provided to construct a robust model using structural learning of BN from historic data. Finally, the returning predictive results and the predictive results are compared to other methods including non-probabilistic and probabilistic models for seismic liquefaction using the metrics of the overall accuracy, the area under the curve of receiver operating characteristic, prediction, recall and F1 score. The methodology proposed in this paper achieved better performance, and we discussed the power and value of the proposed approach at the end of this paper, which suggest that BN is a good alternative tool for seismic liquefaction prediction.  相似文献   
112.
针对极端学习机(Extreme Learning Machine,ELM)用于日长(Length-Of-Day,LOD)变化预报过程中,样本输入方式对预报结果的影响进行了研究。采用跨度、连续和迭代3种样本输入方式对日长变化进行预报。结果表明,不同的样本输入方式对预报结果有很大影响,样本按跨度输入的预报精度最低;样本采用连续输入方式在短期和中长期预报中预报精度较高,但计算速度较慢,较适合中长期预报;样本按迭代输入方式的短期预报精度稍优于连续输入方式,而中长期预报精度则不如连续输入方式,但具有较高的预报效率。这对于日长变化的实时快速预报有着较高的现实意义。  相似文献   
113.
蝗虫是常见的害虫之一,对农作物和生态系统具有很大的危害,采用常规的方法对蝗虫进行监测存在一定局限性,为了有效应用海量野外影像数据实现对蝗虫实时监测,本文建立了一种基于深度学习网络的蝗虫自动识别模型。利用手机模拟摄像头获取的内蒙古锡林浩特附近草原的280张蝗虫的RGB图像,采用深度学习算法中的Faster R-CNN(Faster Region-based Convolutional Neural Network)网络结构建立了蝗虫识别模型。经验证该模型的精确度为0.756,可以较准确地将蝗虫从野外复杂环境中识别出来,与以往同类研究相比,在识别结果和实用性方面均有较大的进步。该模型是建立蝗虫实时监测系统的基础,可以为蝗虫的防治提供辅助信息,同时该网络结构还可以应用于其他害虫的识别,具有较强的推广性,拓宽了深度学习算法的应用领域。  相似文献   
114.
利用最新的深度学习算法,即卷积长短期记忆(Convolution Long-Short Term Memory)神经网络,构建基于深度学习的人工智能短临预报系统,以广州地区2019年3-5月雷达观测的数据为输入进行训练,然后进行短期1h内的降水预报。利用常用的统计评分指标(探测率POD、误报率FAR、临界成功指数CSI,相关系数CC)检验模型。结果表明,预报结果与实际观测的相关系数在1h内预报均保持在0.6以上,在1h内预报探测率均保持在80%以上,临界成功指数在降水强度为10mm·h^-1时,基本保持在60%,误报率均小于40%。  相似文献   
115.
随着计算机网络技术的迅速发展和计算机协同工作CSCW理论和技术研究的深入,计算机协同学习(Computer Supported Collaborative Learning)的思想逐渐被引入计算机网络教育的应用中.目前大多数的协同学习系统采用了C/S结构.提出的基于JXTA的协同学习系统采用了P2P(Peer-to-Peer)结构,满足了协同学习的一般需求,具有安全性、可伸缩性和可扩展性.  相似文献   
116.
21世纪高校GIS本科人才培养方案的研究   总被引:20,自引:3,他引:17  
地理信息系统专业是一个新办专业,就目前而言,从教学计划、教学大纲、课程设置、教材的系统建设等方面都还存在问题。主要从GIS本科的培养目标计划、课程体系建设、实践教学及教与学的关系等方面阐述了思想,以与大家探讨如何建设一个规范、成熟的地理信息系统专业。  相似文献   
117.
Rural production landscapes in Australia are experiencing a rapid rate of change as a result of, among other factors, climate change, biodiversity loss and changing societal values. Consequently, there is increasing pressure on producers to increase their sustainability. Understanding how producers perceive themselves in the context of this changing landscape is limited but important for the design of policy effective for achieving sustainability. This paper is based on a case study in the north-eastern Australian rangelands that included face-to-face interviews with 28 beef producers and a telephone survey with another 91 producers. The study investigated male and female beef producers' self-perceived roles in life through a lens of different farming discourses and the relationship between these roles and beliefs aligned with sustainability. Results revealed that although producers' self-percieved roles in life were being constructed through a mix of more or less ‘traditional’ discourses, tradition was still a strong influence. Producers who strongly identified with roles linked to ‘less traditional’ discourses were more likely than those who strongly identified with production-orientated roles to agree with beliefs that favoured nature conservation, learning and adapting to change. Increased opportunities for producers to participate in alternative discourses would appear important for fostering a self-identity that is open to learning, difference and change.  相似文献   
118.
Abstract

This article reviews the benefits of field-based instruction, particularly as it complements traditional classroom learning. It suggests that direct observation and hands-on learning associated with field-based instruction raise students' interest level and improve their understanding and long-term retention of targeted concepts. In addition, planning, implementation, and evaluation strategies are provided and recommendations are outlined for instructors interested in organizing or improving a field course at their learning institution. The park management field course offered between spring and summer semesters at Oklahoma State University provides an example of the major components of a successful field course.  相似文献   
119.
《The Journal of geography》2012,111(4):211-212
Abstract

This article advocates that geography teachers undertake field studies of human systems with their students. A field trip process is described that helps teachers to guide students to explore and analyze a real human system with the expressed goal of building skills that can transfer to and complement a wide range of geographic learning tasks identified in Geography for Life: National Geography Standards 1994. Students are taken to a human system, such as a supermarket or a hotel. In groups, students interview as well as tour with a representative of a key department of the human system. Using teacher-supplied materials, groups create models or visual schematics of the whole human system they studied. The model must show the complex as a collection of interdependent elements with distinct functions. The learning outcomes achieved by students are a collection of geographic skills ideal for transfer to subsequent geographic investigations of urban places and or regions.  相似文献   
120.
Abstract

The interpretation of landscapes is an important way to learn about geography in environmental education. A Landscape Guide to the Bachelor Reserve applies geographic/historical and biological/ecological perspectives to the interpretation of ten landscape scenes along a three-mile walking tour. For each scene, the guide describes the environmental setting, the composition and structure of the vegetation, and the history of human influences. Questionnaire and field assessments document a well-received interpretive tool, and the need to guide participants across land transitions and interpret land use history clearly. Landscape guides can be used in school/community land labs and contribute to holistic learning and multidisci-plinary exercises in formal and informal environmental education programs.  相似文献   
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