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41.
地质调查正在从“数字化”走向“智能化”,需要在大数据思维的指导下,面向非结构化数据开展机器阅读和地质知识的自动提取。地学命名实体和关系联合提取是当前研究的难点和核心。本文采用基于大规模预训练中文语言模型的BERT—BiLSTM—CRF方法开展岩石描述文本命名实体与关系联合提取。首先,通过收集数字地质填图工作中的剖面测量和路线地质观测数据,建立岩石描述语料;然后,在岩石学理论指导下分析岩石知识组成,完成岩石知识图谱命名实体与关系的模式设计,标注岩石语料;最后,开展岩石描述语料知识提取的深度学习训练和消融试验对比。试验结果显示,大规模预训练中文语言模型(BERT)对岩石描述语料知识提取具有较高的适用性。推荐的BERT—BiLSTM—CRF模型方法对岩石命名实体与关系联合提取的准确率(F1值)为91.75%,对岩石命名实体识别的准确率(F1值)为97.38%。消融试验证明基于BERT的词嵌入层对岩石描述知识提取的性能提升影响显著,双向长短时记忆网络模型层(BiLSTM Layer)能提升实体关系联合提取性能。 相似文献
42.
Fake news about climate change refers to fabricated information that mimics the appearance of legitimate reporting but is intended to mislead consumers. In light of concerns about fake news regarding climate change and other topics, researchers and media providers have been searching for ways to limit its spread and influence. This study tested the effect of two simple interventions, both of which primed critical thinking, on individuals’ evaluation of the credibility of real and fake news about climate change on Facebook. Through an online experiment (n = 2,750 participants), participants either read a series of guidelines for evaluating news online, or read and then rated the importance of each guideline; a control group was not exposed to guidelines of any type. We found that participants exposed to both types of guidelines reported a reduced likelihood to trust, like, and share fake news about climate change on Facebook. Importantly, exposure to these guidelines did not diminish individuals’ likelihood to trust, like, or share legitimate climate news. The effect sizes for both types of intervention were small. However, because of the scale and speed at which social media operates, even a small reduction in users’ likelihood to trust, like, and share fake news could be meaningful and impactful. 相似文献
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Jeffrey D. Hamerlinck 《制图学和地理信息科学》2015,42(4):11-17
Popular and professional interest in maps and map-making has never been greater. Despite this engagement, introductory skills courses in “map use” have largely disappeared in undergraduate geography and cartography programs at US universities, with research indicating that both map-use course enrollments and the existence of such courses themselves are on the decline. While the map-use course and its content may have been replaced by, repackaged as, or incorporated into an integrated geographical information systems-cartography–remote sensing foundations course, how do we ensure that an understanding of maps and their unique characteristics is not lost in the mix? This essay describes a recent course redesign experience incorporating information literacy, technology fluency, and spatial thinking principles to maintain map-use concepts, skills, and appreciation in an introductory geographic information science and technology (GIS&T) foundations course, meeting both GIS&T and general education curricular goals. 相似文献
45.
《The Journal of geography》2012,111(2):55-63
Abstract Experiential learning pedagogies are being adopted across undergraduate education and touted as an effective strategy for enhancing student learning. This paper develops an explanation for how and why such pedagogies can foster students' critical thinking and learning. Drawing on data collected from first-year students in “field based” urban geography courses at an urban university, I show how students' existing knowledge of urban spaces and specific parts of the city is constructed from a variety of sources and experiences, and can be incorporated in experiential learning activities in ways that foster critical learning. Such an approach is crucial to creating learning environments in higher education that include a greater diversity of student identities and life experiences. 相似文献
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河西地区生态重建与经济可持续发展战略研究 总被引:18,自引:1,他引:18
在我国西部大开发战略实施过程中,河西地区充当着“开发极”和“开路先锋”的重要角色,提出了河西地区生态重建与经济可持续发展的战略思路,包括把生态重建作为经济持续发展的切入点,实施“大生态”战略,最大限度地节水,创造条件小范围调水,实施“大节水”战略,运用市场机制和高新技术开拓资源优势,实施“大资本”战略,推进工业化和农业产业化与结构转换,实施“大调整”战略,营造大开发的投资环境与开放环境,实施“大联通”战略,最终把河西地区建成一个经济持续发展,人民生活水平显著提高,生态环境逐步改善的绿色生态走廊和经济可持续发展走廊。 相似文献
48.
盐是关系国计民生的重要物资,既是人类生活的必需品,又是氯碱基础化工原料。本文以地质学与经济学相结合的观点,通过对四川岩盐资源优势、开发利用现状、技术经济条件、川盐需求预测及开发利用前景等的分析,提出了四川岩盐开发的战略对策和建议,对促进四川岩盐资源开发和经济发展具有重要意义,并为四川地矿、盐业、化工等部门制定规划提供科学依据。 相似文献
49.
The intent of this paper is to explore how ‘reel’ and ‘real’ landscapes can be rendered dialectic. The analysis focuses on
the filming of Tarzan's Secret Treasure (1941) at the wildlife preserve of Wakulla Springs in Florida, which was administered
by the financial tycoon Ed Ball. Using Mitchell's recent commentaries on ‘good’ and ‘bad’ dialectics as our entry point, we
offer two readings of this cinematic process. The first renders the on and off screen Wakulla Springs as ideological fodder,
serving to valorise capital, masculinity and whiteness. The second reading addresses how this place has been actively constructed
from discourses pertaining to class, gender and race, such that Wakulla exists as a series of fully relational spaces within
diverse contexts, both ‘real’ and ‘reel’. In structuring our analysis in this manner, we hope to make clear why it does indeed
matter for film geographers to acknowledge the conceptual presumptions brought to bear in the framing of the real and the
reel as objects of analysis.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
50.
本文在明确农业地质学概念、内涵及其意义的基础上,简要叙述了贵州农业地质背景与条件,初步提出了该工作的基本思路和分层次部署农业地质工作的建议. 相似文献