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171.
We conduct an analysis of 1835 pledges to 10 music production projects hosted on the largest Brazilian crowdfunding platform, namely the Catarse Web site, and we assess the relation between the fundraising accumulation period, the donor–entrepreneur distance and the propensity of donors to back projects. Our results suggest a significantly negative association between distance and the value of capital pledged to projects, which is consistent with the notion that the entrepreneur’s network of close contacts might play a central role in funding. Furthermore, our results contradict the idea that crowdfunding reduces the inhibiting effect of donor–entrepreneur distance. In addition, the results show that a long project exposure is associated with higher values of pledges. These results suggest practical implications for the study of crowdfunding as a financing platform. This study contributes to the literature on the use of crowdfunding as an alternative funding source in a major emerging market.  相似文献   
172.
A growing body of literature is devoted to testing the reality of the “long-tail” phenomenon. This literature is mostly, if not exclusively, focused on the impact of Internet on the distribution of sales by product. However, the long tail also raises the issue of a possible change in the usual market structure of cultural industries: an oligopoly with a competitive fringe. To our knowledge, no paper addresses the following question: If the long-tail effect does exist, is it of more benefit to small or dominant publishers? The aim of this paper was to address this issue in the context of the French publishing industry. Our main findings are as follows: (1) the market concentration of the French book industry is lower online than offline and (2) the difference in concentration between the two channels of distribution tended to widen over the period 2004–2010. Strategies adopted by leading publishers on the Web do not allow them to maintain the market share obtained with bricks-and-mortar retailers. Furthermore, we show that the market share lost by dominant firms is captured by small publishers online and by medium-sized publishers in conventional stores.  相似文献   
173.
174.
Are universities able to operate as strategic actors? An organisational sociology based approach supported by a comparative field research project identifies three types of social, cultural and cognitive processes that play a decisive role in building and implementing local capabilities required to mobilise a strategic capacity. The paper identifies how much these processes are present in the four ideal-types of universities defined by crossing their reputation and their metrics-based performance. Such a meso deterministic perspective suggests that universities may position themselves as proactive actors or principals, and not just as agents of national reforms and political demands. Nevertheless, their ability to do it varies according to their type. The paper also explores the implications of such findings for institutional leadership and steering policymakers.  相似文献   
175.
There is a crisis of valuation practices in the current academic life sciences, triggered by unsustainable growth and “hyper-competition.” Quantitative metrics in evaluating researchers are seen as replacing deeper considerations of the quality and novelty of work, as well as substantive care for the societal implications of research. Junior researchers are frequently mentioned as those most strongly affected by these dynamics. However, their own perceptions of these issues are much less frequently considered. This paper aims at contributing to a better understanding of the interplay between how research is valued and how young researchers learn to live, work and produce knowledge within academia. We thus analyze how PhD students and postdocs in the Austrian life sciences ascribe worth to people, objects and practices as they talk about their own present and future lives in research. We draw on literature from the field of valuation studies and its interest in how actors refer to different forms of valuation to account for their actions. We explore how young researchers are socialized into different valuation practices in different stages of their growing into science. Introducing the concept of “regimes of valuation” we show that PhD students relate to a wider evaluative repertoire while postdocs base their decisions on one dominant regime of valuing research. In conclusion, we discuss the implications of these findings for the epistemic and social development of the life sciences, and for other scientific fields.  相似文献   
176.
[目的/意义] 组织氛围优化有助于提升馆员对图书馆的满意度和馆员的工作热情。案例分析有助于在更多图书馆推广组织氛围测评,进而为管理优化决策提供支持。[方法/过程] 南京农业大学图书馆借鉴美国图书馆界开展ClimateQUALTM测评的做法,在对ClimateQUALTM量表进行本地化改造的基础上,分别于2011和2015年对图书馆组织氛围开展量化测评,通过分析数据寻找存在的问题并不断优化管理方案。历经4年多时间,完成图书馆组织氛围的优化探索过程。[结果/结论] 前后两次测评数据对比显示,2015年得分较2011年整体有所提升,同时集思广益、创新、激励竞争、用户服务和团队合作5个指标得分明显提升,说明组织氛围测评的必要性和管理创新举措的有效性。  相似文献   
177.
在初中化学教学阶段,由于受年龄和身心发展的影响,学生思维的运作形式主要是具体形象的推理思维,包括演绎推理和归纳推理,本文结合具体的案例,从定性推理思维和定量推理思维两个方面加以分析。1 定性推理思维及其案例分析定性推理是确定研究对象具有某种属性的推理  相似文献   
178.
This paper proposes a learning-based method for text detection and text segmentation in natural scene images. First, the input image is decomposed into multiple connected-components (CCs) by Niblack clustering algorithm. Then all the CCs including text CCs and non-text CCs are verified on their text features by a 2-stage classification module, where most non-text CCs are discarded by an attentional cascade classifier and remaining CCs are further verified by an SVM. All the accepted CCs are output to result in text only binary image. Experiments with many images in different scenes showed satisfactory performance of our proposed method.  相似文献   
179.
INTRODUCTION There is increased need in recent years for strengthening or rehabilitation of existing reinforced concrete structures adversely affected by overloading, construction material deterioration, seismic loads, structural deformation, etc. An effective method for increasing the shear capacity of reinforced concrete columns is the use of externally bonded carbon fiber reinforced plastic (CFRP) systems (ACI, 2002). FRP systems were first applied to reinforced concrete col-umns i…  相似文献   
180.
A pre-treatment methodology for clenbuterol hydrochloride (CLEN) isolation and enrichment in a complex matrix environment was developed through exploiting molecularly imprinted polymers (MIPs). CLEN-imprinted polymers were synthesized by the combined use of ally-β-cyclodextrin (ally-β-CD) and methacrylic acid (MAA), allyl-β-CD and acrylonitrile (AN), and allyl-β-CD and methyl methacrylate (MMA) as the binary functional monomers. MAA-linked allyl-β-CD MIPs (M-MAA) were characterized by Fourier transform-infrared (FT-IR) spectroscopy and a scanning electron microscope (SEM). Based upon the results, M-MAA polymers generally proved to be an excellent selective extraction compared to its references: AN-linked allyl-β-CD MIPs (M-AN) and MMA-linked allyl-β-CD MIPs (M-MMA). M-MAA polymers were eventually chosen to run through a molecularly imprinted solid-phase extraction (MISPE) micro-column to enrich CLEN residues spiked in pig livers. A high recovery was achieved, ranging from 91.03% to 96.76% with relative standard deviation (RSD) ≤4.45%.  相似文献   
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