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111.
为避免或减轻工程结构在建造和运营期间因结构振动产生不同程度损伤,造成安全隐患危及人们生命财产安全,针对结构振动损伤识别技术展开研究,探讨不同深度学习方法发展情况及其利弊,寻找更具可行性的损伤识别方法,并对其最新研究及应用现状进行全面综述。研究结果表明:应用深度学习开发新的结构损伤识别技术,无需冗余的数据预处理以及手工提取损伤特征,实现以较高精度实现损伤识别任务;一维卷积神经网络(1D-CNN)以其独特的应用优势,在数据样本有限条件下较二维卷积神经网络(2D-CNN)表现更为出色。研究结果可为数据驱动的结构损伤识别问题提供新思路,进一步完善土木结构健康监测研究体系。  相似文献   
112.
为探究邻苯二甲酸二丁酯(DBP)影响阿尔茨海默病(AD)大鼠学习记忆能力的分子机制,将56只SPF级5~6周龄雌性Wistar大鼠随机平均分为7组:阴性对照组、0.25 mg·kg-1·d-1 DBP 组、2.5 mg·kg-1·d-1 DBP 组、25 mg·kg-1·d-1 DBP 组、250 mg·kg-1·d-...  相似文献   
113.
ABSTRACT

Policy evaluation has grown significantly in the EU environmental sector since the 1990s. In identifying and exploring the putative drivers behind its rise – a desire to learn, a quest for greater accountability, and a wish to manipulate political opportunity structures – new ground is broken by examining how and why the existing literatures on these drivers have largely studied them in isolation. The complementarities and potential tensions between the three drivers are then addressed in order to advance existing research, drawing on emerging empirical examples in climate policy, a very dynamic area of evaluation activity in the EU. The conclusions suggest that future studies should explore the interactions between the three drivers to open up new and exciting research opportunities in order to comprehend contemporary environmental policy and politics in the EU.  相似文献   
114.
A palaeoecological study was conducted to investigate past environmental conditions and vegetation dynamics around the southwestern Ljubljana Moor. In order to find potential regularities and/or dependencies among co-existent plant species through time, different machine learning methods were applied to pollen records from the cores taken at Bistra and Ho?evarica. The data comprised relative pollen frequencies of the most common plant genera/families at particular core depths that correspond to particular ages in the Early and Mid Holocene periods. The applied methods include equation discovery and hierarchical clustering. Both methods have found plausible and explainable relationships among identified plant genera/families.  相似文献   
115.
ABSTRACT

European climate policy faced increasing constraints during the economic and Eurozone crises (2008–2014). The European Commission subsequently refocused policymaking toward integrating climate objectives into other policy areas such as energy and the 2014–2020 European Union (EU) budget. The conditions for successful climate policy integration (CPI) are analyzed, focusing on the compatibility of key actors’ beliefs. In renewable energy policy, CPI was successful as long as the co-benefits and related policy-core beliefs of energy security, rural economic development and climate action coexisted harmoniously. Once conflict among these policy-core beliefs emerged during the biofuels controversy, CPI was weakened as actors with competing economy-focused beliefs controlled the decision-making process. The case of EU budget climate mainstreaming illustrates how actors can add climate objectives into legislation despite meaningful discussion being ‘crowded out’ by other priorities. The findings highlight the importance of low conflict between departments, compatible beliefs and policy priorities for successful CPI.  相似文献   
116.
Because behavioral variation within and among populations may result from ecological, social, genetic and phenotypic differences, identifying the mechanism(s) responsible is challenging. Observational studies typically examine social learning by excluding ecological and genetic factors, but this approach is insufficient for many complex behaviors associated with substantial environmental variation. Indian Ocean bottlenose dolphins (Tursiops sp.) in Shark Bay, Western Australia show individual differences in foraging tactics, including possible tool use with marine sponges and social learning may be responsible for this diversity. However, the contributions of ecological factors to the development of these foraging tactics were not previously investigated. Here, we determined the relationship between ecological variables and foraging tactics and assessed whether differences in habitat use could explain individual differences in foraging tactics. We monitored 14 survey zones to identify how foraging tactics were spatially distributed and matched behavioral data to the ecological variables within each zone. Three of four foraging tactics were significantly correlated with ecological characteristics such as seagrass biomass, water depth, presence of marine sponges and season. Further, individual differences in habitat use were associated with some tactics. However, several tactics overlapped spatially and previous findings suggest demographic and social factors also contribute to the individual variation in this population. This study illustrates the importance of environmental heterogeneity in shaping foraging diversity and shows that investigating social learning by ruling out alternative mechanisms may often be too simplistic, highlighting the need for methods incorporating the relative contributions of multiple factors.  相似文献   
117.
针对传统教学方法存在的问题,在《营销统计》课程教学实践中采用"教学做"一体化教学模式,构建了"一条主线、两个知识模块、三种关键能力"的教学内容体系,将统计调查工作设置为一个实训项目,形成"一个项目四个环节"的教学过程。  相似文献   
118.
“教学做一体化”课程有利于理论教学与实践教学相结合,有利于高职学校长期健康的发展。“教学做一体化”教学模式是基于实际工作过程导向,以工作中典型项目任务引领,激发学生兴趣,以满足培养高等技能型人才的迫切需要。一体化课程的构建应通过项目设立、建立小组、实施、反馈等环节完成。  相似文献   
119.
针对企业安全管理体系相关工作与日常安全管理之间存在的"两张皮"现象,首先借助企业生产安全"问题空间"和"解空间"的概念,探讨了企业安全管理的出发点和落脚点;然后,围绕企业具体安全问题的确认和求解,分析了如何在组织层面通过三阶"学习循环"推进体系功能的实现;最后,基于RACI模型探讨了如何在个体层面支持和响应组织层面的各阶"学习循环"以真正实现体系的功能。总之,"两张皮"现象主要来自企业生产安全"目的"和"手段"不能有效对接,安全管理体系建设和功能实现应从辨识和解决企业实际问题入手。  相似文献   
120.
Several recent studies have tested the hypothesis that song quality in adult birds may reflect early developmental conditions, specifically nutritional stress during the nestling period. Whilst all of these earlier studies found apparent links between early nutritional stress and song quality, their results disagree as to which aspects of song learning or production were affected. In this study, we attempted to reconcile these apparently inconsistent results. Our study also provides the first assessment of song amplitude in relation to early developmental stress and as a potential cue to male quality. We used an experimental manipulation in which the seeds on which the birds were reared were mixed with husks, making them more difficult for the parents to obtain. Compared with controls, such chicks were lighter at fledging; they were thereafter placed on a normal diet and had caught up by 100 days. We show that nutritional stress during the first 30 days of life reduced the birds’ accuracy of song syntax learning, resulting in poorer copies of tutor songs. Our experimental manipulations did not lead to significant changes in song amplitude, song duration or repertoire size. Thus, individual differences observed in song performance features probably reflect differences in current condition or motivation rather than past condition.  相似文献   
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