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11.
ABSTRACT

This paper proposes a novel approach for understanding money users’ relation to monetary governance institutions. It first describes the stakes involved in monetary governance from a neo-chartalist/MMT perspective. In a second step, it discusses existing contributions on the relation between money issuer and money users, highlighting the literatures on central bank legitimacy and the social construction of money. It argues that neither allows for an analysis of the relation between monetary institutions and money users that takes the latter’s knowledge seriously. It then argues that the concept of moral economy can enrich scholarly analysis. Moral economies of money are defined as collective practices in which money users articulate demands as part of an understanding of money as a public good. Finally, the paper deploys the moral economy of money perspective to reconstruct the changing relation between institutions of monetary governance and money users since the Great Depression in the U.S. It shows how New Dealers silenced a moral economy of money, discusses fragmented moral economies after World War II, and the partial reemergence of such moral economies after the Great Financial Crisis. The paper concludes by discussing political implications and suggestions for further research.  相似文献   
12.
李慧  胡吉霞 《图书情报工作》2020,64(18):114-125
[目的/意义] 针对包含单一类型知识单元的知识网络难以全面反映学科知识结构的问题,提出一种从多维度进行知识网络结构融合的方法,为学科领域知识结构挖掘提供借鉴。[方法/过程] 利用LDA及TF-IDF方法抽取学科知识单元,然后运用语义相似度和关键词共现分析方法构建3个学科知识子网络:主题网络、关键词网络和实体网络,并采用空间节点传递对齐方法对齐子网络节点,接着设计基于图卷积操作的自编码模型对知识节点进行表示,最后通过计算余弦相似度重构学科知识网络。[结果/结论] 实验部分以人工智能领域为例,构建融合主题、关键词和实体的学科知识网络并展开分析,实验结果表明,本文所提方法能有效地揭示学科领域研究内容和知识结构,为学科知识发现与组织研究提供有益参考。  相似文献   
13.
ABSTRACT

This paper examines the social construction of ‘fashionability’ – namely, what is ‘desirable’ and ‘fashionable’ – with reference to the concept ‘cultural mediators’ that foregrounds agency, negotiation and the contested practices of market actors in cultural production. It zeroes in on the cultural mediators’ attitudes and positions in the two markets by drawing on 25 in-depth interviews with industry veterans. It shows that the mediators in South Korea and China increasingly occupy hybrid occupational roles and social positions across industries and sectors yet achieve limited success in countering the status quo of Western fashion through mediation. The analysis contributes to the literature with a categorisation of seven mediation practices that shape the valuation of fashion products (i.e. ‘fashionability’) in two ways. Empirically, this categorisation illuminates how cultural mediators make reference habitually to the broader social and cultural contexts to co-construct cultural-aesthetic objects. Theoretically, it advances a cultural-economic approach to the understanding of cultural mediation and challenges the reductionist viewpoint of actor–network theory through the notion of a matrix of cultural-economic agency.  相似文献   
14.
ABSTRACT

Background: Pedagogical models have become an established component of physical education over the past several decades. One such model, the Teaching Personal and Social Responsibility model, has gained momentum in practice and research, though little is known regarding its use in preservice teacher training. The model follows a flexible format focused on teaching life skills (e.g. leadership) that can be applied in all lived ecologies. Occupational socialization theory provides insight into the pretraining and teacher education experiences of preservice teachers that shape their understanding and practice of physical education and associated pedagogical models.

Aims: The purpose of this study was to understand the influence of a sequence of methods courses and early field experiences on U.S. preservice teachers’ understanding and implementation of the teaching personal and social responsibility model with youth from a community affected by poverty.

Method: This study took on a phenomenological and social constructivist approach. Ten preservice teachers (9 males, 1 female) took part in the study. The participants were an average age of 22.10 years old (SD?=?4.38) and seven identified as White and three as Black. Each participant was enrolled in methods and early field experience coursework that provided scaffolded training in primary education in a community affected by poverty. Preservice teachers team-taught groups of 10–15 children twice a week along with one day committed to on-campus reflection. Data collection included autobiographical essays, critical incident reports, reflective journals, non-participatory observations and field notes, and semi-structured interviews. Data were analyzed deductively through the lens of occupational socialization theory, and inductively as theory divergent trends were sought. Open and axial coding was completed with member checking throughout, resulting in a final set of themes and subthemes.

Findings: The preservice teachers initially struggled to connect with their students due to conflicting backgrounds, but the teaching personal and social responsibility model guided the relationship-building process. As the model was continuously utilized, more empathy and care were shown towards the children. Preservice teachers felt there was a lack of progression in positive behaviors but were able to empower youth and felt that the model was culturally relevant. Overtime, the students began to appreciate the affective domain despite the challenge of working in a community affected by poverty through frustration towards the larger system limiting any potential progress was present.

Conclusions: Subjective theories transitioned to include relationship building and life skills learning, likely because of the extended field experience and faculty support. The preservice teachers desire to connect with and teach the students well displays the connection between models-based practice and positive relationships. Preservice teachers’ knowledge of their students was limited as it was based on secondhand knowledge of youth, teacher educators, and school staff. Evidence indicates some cultural responsiveness development though there were also elements of a deficit model due to white privilege and class differences. Further work explicitly integrating a culturally relevant approach and social justice in teacher education programming should occur.  相似文献   
15.
人工智能相关技术的迅猛发展和逐步普及,使得情报学难以避免人工智能的融合趋势,无论这种融合是主动为之或是被动选择。然而学界对人工智能时代情报学学科的发展走向并未予以充分探讨,大部分研究均将焦点置于大数据与下一代互联网环境中进行论述。本研究将人工智能时代情报学学科走向解构为"本体论""感知论""方法论""服务论"四个论题,对每个论题借由理论面向与实践面向的二分法展开阐释,并从整体视角上提出应在人工智能洪流中找准情报学定位,不能忽视"人"在情报学中的价值以及重视跨学科融合、跨领域应用的发展趋势。  相似文献   
16.
为提高船舶航迹预测精度,解决准确建模难度大和神经网络易陷入局部最优的问题,考虑实时获取目标船AIS数据较少的特点,提出一种基于支持向量机(support vector machine,SVM)的航迹预测模型。选择AIS数据中的航速、航向和船舶经纬度作为样本特征变量;采用小波阈值去噪的方法处理训练数据;采用差分进化(differential evolution,DE)算法对模型内部参数寻优以提高模型收敛速度和预测精度。选取天津港实船某段航迹的AIS数据,比较基于DE-SVM与基于BP神经网络的航迹预测模型的仿真结果。结果表明,基于DE-SVM的航迹预测模型具有更高的预测精度,简单、可行、高效,且耗时少。  相似文献   
17.
认知无线电是一种可用于有效缓解当前频谱资源紧张的技术,而频谱感知是认知无线电的前提。针对低信噪比情况下频谱感知性能差的问题,提出一种将信号高阶统计量、协方差矩阵特征值与神经网络相结合的合作频谱感知算法。该算法考虑到认知用户与授权用户的信道衰落情况,利用神经网络较强的多分类能力,将最大-最小特征值之比、平均-最小特征值之比以及高阶统计量作为特征参数,通过神经网络实现合作频谱感知。仿真结果表明,该算法不仅在低信噪比情况下较其他算法具有更高的频谱检测率,而且对频谱中信号的调制类型也有较高的识别率。  相似文献   
18.
针对目前起重机安全评价过于依赖主观权重且忽视起重机安全状态变化趋势的问题,建立基于改进博弈论组合赋权法(improved combination weighting method of game theory,ICWGT)和灰色关联分析法的起重机安全评价体系。在该评价体系中,收集样本数据以确定评价值,构建评价等级空间来计算起重机行为特征序列与标准行为特征序列的关联系数。运用ICWGT在层次分析法和信息熵 未确知测度理论确定的主、客观权重中寻找平衡。充分考虑专家经验和样本数据,确定优化权重以改善关联系数的分配问题,从而获取起重机灰色关联度评价值和安全等级,旨在对起重机安全状态变化趋势进行更加准确的定量描述和定性分析。实例分析验证了该评价体系的有效性。  相似文献   
19.
为提高锚泊安全评价精度,保障船舶锚泊安全,针对传统锚泊安全评价方法未考虑评价等级界限的不确定性和模糊性等问题,将正态云可拓理论应用于锚泊安全评价中。采用层次分析法和基于可拓学的简单关联函数确定权重的方法分别确定锚泊安全评价指标的主观和客观权重,通过经验因子将主观与客观权重进行结合。构建基于正态云可拓理论的锚泊安全评价模型,计算待评物元与标准可拓物元的关联度,通过信息熵理论确定锚泊安全等级。根据信息熵理论定义可信因子,使得评价结果的可信度易于定量计算。实例计算验证了本模型的有效性和优越性。  相似文献   
20.
ABSTRACT

As an important part of art and culture, ancient murals depict a variety of different artistic images, and these individual images have important research value. For research purposes, it is often important to first determine the type of objects represented in a painting. However, the mural painting environment makes datasets difficult to collect, and long-term exposure leads to underlying features that are not distinct, which makes this task challenging. This study proposes a convolutional neural network model based on the classic AlexNet network model and combines it with feature fusion to automatically classify ancient mural images. Due to the lack of large-scale mural datasets, the model first expands the dataset by applying image enhancement algorithms such as scaling, brightness conversion, noise addition, and flipping; then, it extracts the underlying features (such as fresco edges) shared by the first stage of a dual channel structure. Subsequently, a second-stage deep abstraction is conducted on the features extracted by the first stage using a two-channel network, each of which has a different structure. The obtained characteristics from both channels are merged, and a loss function is constructed to obtain the classification result. This approach improves the model's robustness and feature expression ability. The model achieves an accuracy of 84.24%, a recall rate of 84.15%, and an F1-measure of 84.13% when applied to a constructed mural image dataset. Compared with the AlexNet model and other improved convolutional neural network models, the proposed model improves each evaluation index by approximately 5%, verifying the rationality and effectiveness of the model for automatic mural image classification. The mural classification model proposed in this paper comprehensively considers the influences of network width and depth and can extract rich details from mural images from multiple local channels. An effective classification method could help researchers manage and protect mural images in an orderly fashion and quickly and effectively search for target images in a digital mural library based on a specified image category, aiding mural condition monitoring and restoration efforts as well as archaeological and art historical research.  相似文献   
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