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331.
随着互联网与信息技术的快速发展,线上线下混合式学习逐渐得到普及与应用。混合式学习强调学生的主体作用,注重学生的自主学习、协作学习和个性化学习,是良好的适合高等教育的创造性学习模式。但是在目前的混合式学习模式下,学生对知识的加工、梳理、整合能力不够,构建完整知识体系的自主学习能力稍显薄弱,因此亟需更多引导。文章综合分析了混合式学习模式的优缺点,建议引入人工智能领域的知识图谱概念,作为新的教学元素以引导和加强学生的自主学习过程,由此构建了基于知识图谱的增强型混合式学习模式。该模式在2020年南京大学《古无脊椎动物学》课程中进行了实践,进一步证明其在改善学生自主学习能力方面的潜力。  相似文献   
332.
Almost every country requires some form of environmental licensing prior to the inception of development projects that may affect the integrity of the environment and its social context. We developed a new conceptual and methodological model to instruct the assessment of the potential impacts posed by proposed projects. Susceptibility to Human Interventions for Environmental Licensing Determination (SHIELD) includes a novel geomorphological interpretation of the Environmental Impact Assessment (EIA). It considers the impact of human interventions on geomorphological processes and landscape functioning in the context of the entire ecosystem, going further than the classical concept of vulnerability. Estimated susceptibility of the site informs the screening stage, allowing local conditions to help define the criteria used in the process. Similarly, the level of detail of the environmental baseline is scoped by considering the degree of disturbance of natural processes posed by human intervention. Testing this geomorphological susceptibility model on different kinds of environments would allow shifting the environmental licensing practices from the prevailing anthropocentric and static conception of the environment towards an Ecosystem Approach. SHIELD addresses the need to improve the screening and scoping stages that form the basis of the rest of any EIA. SHIELD introduces several innovations to EIA including the incorporation of fuzzy logic, a preassembled database of contributions form experts, and a shifting of emphasis from the type of proposed intervention to the type of environment and its relative susceptibility.  相似文献   
333.
为了解决金坛储气库的安全平稳运行及下一步开发建设等问题,在综合利用岩心、薄片、测井、地震以及分析化验等资料的基础上,对该区含盐层系沉积特征、控制因素及沉积模式进行了研究。结果表明:阜宁组四段含盐层系发育石盐岩、硫酸盐岩、碳酸盐岩、泥岩、粉砂岩5种岩石类型,具有6种层理构造和2种化学成因构造;沉积时气候干旱炎热,盐度较高。研究区含盐层系在测井上表现为箱形、钟形、齿形、漏斗形及平直形5种形态,地震上表现为平行状、杂乱丘状、舌形孤立状3种反射特征;含盐层系属于盐湖沉积,可识别出中心膏盐岩、过渡带碳酸盐岩、边缘带砂泥岩3种亚相及7种微相,含盐层系在不同层序内部沉积特征和分布规律各异,沉积中期高位体系域盐岩厚度最大;古地貌控制含盐层系沉积微相类型和分布特征,水体开放程度控制沉积序列演化和岩性组合,湖平面变化控制含盐层系岩石类型和发育规律。研究区存在局限型和广覆型两种成盐模式,湖盆中心的低洼区域为下一步开发建设的有利区域。  相似文献   
334.
335.
We live in a rapidly advancing digital information age where the ability to discover, access and utilize high-quality information in a reliable and timely manner is often assumed to be the norm. However, this is not always the experience of researchers, practitioners and decision makers responding to the challenges of a rapidly changing climate, despite the billions now being made available for investment in climate change adaptation initiatives throughout the world and particularly in developing countries. In recognition of the importance of information in adaptation planning, Article 7.7 of the Paris Agreement sets out clear guidance for parties to develop, share, manage and deliver climate change knowledge, information and data as a means to strengthening cooperation and action on adaptation. This article provides some key lessons and insights on climate change information and knowledge management (IKM) in small island developing States (SIDS) from the perspective of Pacific SIDS. A situation analysis of current climate change IKM practices in Fiji, Tonga and Vanuatu was conducted and key barriers to effective climate change IKM identified. The outcome of this article is a range of pragmatic policy considerations for overcoming common barriers to climate change IKM in the Pacific, which may be of value to SIDS more widely.

Key policy insights

  • The partnership approach of co-investigating climate change IKM barriers in collaboration with Pacific SIDS generated considerable trust, a shared purpose and therefore rich IKM lessons and insights.

  • Turning climate change IKM aspirations into practice is significantly more complicated than expected, and requires a long-term commitment from both national governments and development partners.

  • Pacific SIDS need to establish national guiding climate change IKM Frameworks that leverage rather than duplicate growing national investments in whole-of-government IKM.

  • Reframing climate change IKM in the Pacific towards demand and user needs will be critical to ensuring widespread ownership and participation in IKM solutions that lead to greater adaptation and resilience outcomes.

  • It is also critical that IKM activities in SIDS support the development of national capacity to scope, develop, deploy and maintain decision support systems.

  • Federated IKM systems are ideal for encouraging greater IKM collaboration.

  相似文献   
336.
堆石料的应力-应变曲线具有应变硬化和软化的特性,并且体积变形会伴随着剪缩和剪胀现象的发生;此外,应力水平、应力路径和密度等因素均会对堆石料的力学特性产生显著的影响。基于临界状态土力学的理论框架,建立了适用于堆石料的分数阶下加载面模型,该模型为典型的双屈服模型。在平均主应力p-剪应力q平面,剪切过程中堆石料当前应力状态点和参考应力点分别位于下加载面和参考屈服面上,两者之间的相对位置与孔隙比之差ρ相关。相比于状态参量Ψ,ρ能够额外考虑应力路径对堆石料剪胀特性的影响。新模型的另一个显著特点在于能够考虑堆石料塑性流动方向与加载方向之间的差异性。在不引入塑性势函数的情况下,新模型对屈服函数进行Caputo微分并得到分数阶塑性流动法则,进而统一描述相关联和非相关联的塑性流动法则。新模型具有形式简单且参数较少等优点,所包含的7个材料参数均具有明确的物理意义,并且可以采用常规的室内试验结果进行标定。通过将模型计算结果与Tacheng堆石料在不同初始孔隙比和围压条件下的三轴压缩排水试验结果进行对比分析,结果表明新模型能够准确地描述堆石料的应力-应变曲线和体积变形特点;同时,新模型也能够合理地描述初始孔隙比对堆石料在e-lnp平面(e为孔隙比)临界状态线的影响。  相似文献   
337.
This paper explores the failures of the quota allocation system in the hake fishery in Walvis Bay, Namibia through an examination of the complex processes that link commodities, labour, production, markets, and knowledge in the industrial setting. The relationships between state regulations and public nature point to a specific engagement in which nature is divided, distributed, and owned, namely through the market driven prospects of transferable quotas. This article examines fishing quota as a set of relations that links the transformation of fish from biological organism to global product and thus weaves science, the state, markets, and social relationships into an entanglement of different forms of capital. In this context, the tension between the quota holder, the value of that quota, and their participation in the industry reflects a complex network of capital mediated through various strategies. Based on ethnographic research in the Namibian trawl sector, this article surfaces these modes of capital in the dynamics of the fishing operations. As such, the fishing industry, the company that holds the fishing rights, the government׳s role in quota allocations, the vessels, gear, and technologies, and the relationships and roles of the crewmembers and skippers׳ knowledge all contribute to a particular formulation of fishing practices. Fisher׳s knowledge in industrial fishing practices becomes a site in which to explore the consequences of ITQs that may also begin to destabilise the neoliberal business model for fisheries in times of crisis.  相似文献   
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339.
苏敬 《东北测绘》2012,(8):227-228
详细介绍了运用Adobe Illustrator CS 5软件把方正智绘格式的地图、Word格式的文字融合在一起的地图集制作方法,丰富了地图集的表示内容,增强了地图集的表现力,在地图制作、工艺、及创新方面具有一定的参考价值。  相似文献   
340.
主要探讨在新时期条件下面向矿山类测绘专业人才培养模式的研究,通过合理设置课程、加强实践教学,科研促进教学等方面工作来建立面向矿山型的测绘专业人才培养模式,探索具有特色的应用型人才培养模式。  相似文献   
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