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51.
Current persistent sustainability challenges are widely understood to require transitions and system innovations. As these systemic changes typically emerge from multiple co-evolving innovations, Schot and Geels [2008. Strategic niche management and sustainable innovation journeys; theory, findings, research agenda, and policy. Technology Analysis and Strategic Management 20, no. 5: 537–54] urge to study the interactions between innovation journeys. Their call for multiplicity has been met through several studies. Yet considering that these analyses still leave the attendant navigational challenges underexposed, this article demonstrates the usefulness of nested-case methodologies. Focusing on the ‘intersections’ between interpenetrating case histories, in-depth investigation is combined with broader attention to next-order changes. The relevance and implications of these intersections are illustrated through four innovation journeys in the Dutch traffic management field: unfolding largely in parallel, but sometimes intersecting, they yield a mixed picture of trajectory formation and fragmentation. The phenomenon of emergent incoherence is identified as a key strategic challenge in system innovation processes.  相似文献   
52.
Identity construction involves accumulating cultural, social, and symbolic capital, with initial endowments being accrued through socialization into one’s habitus. This research explores the experiences of individuals that feel a lack of capital, which leads to ambiguity regarding their identities and places in the world. Through in-depth interviews, this interpretive research shows that such individuals may turn to fandom for gaining status and belonging. Fandoms are consumption fields with clear, limited forms of cultural capital. Through serial fandom and engagement with fandom in different ways, individuals were able to learn the skill of identifying and accruing relevant cultural capital. The skill became decontextualized and recontextualized, allowing individuals to transcend fandom and accrue general forms of cultural capital. Learning the skill aids individuals in dealing with the simultaneously debilitating and empowering freedom of contemporary consumer culture. Moreover, gaining cultural capital could be altogether developing into the form of the process we describe.  相似文献   
53.
Traditional vineyards in Spain are being upgraded to trellis vineyards. A key question is to what extent the transition to trellis vineyards is compatible with the environmental preservation goals in Special Protection Areas. This paper presents a GIS-based model to assess the suitability of Special Protection Areas for the development of trellis systems. The model was applied in a Special Protection Area for steppe birds in Castilla-La Mancha, Spain, a region with the largest concentration of vineyards in the world. The model includes three components: (1) a vineyard structure analysis, (2) an analysis of habitat fragmentation, and (3) a suitability analysis. The results showed that 50.9% of the study area, including 82.1% of the existing vineyards, was classified as suitable for transition to trellis systems. In the remaining unsuitable areas an increase in trellis systems should be avoided. The model is a stepping stone for improving the sustainable land use development of Mediterranean agricultural landscapes. Further research is needed to include wider socio-economic and environmental consequences of modernizing viticulture practices.  相似文献   
54.
A high level of fragmentation of farmland ownership is an important underlying cause of land degradation and, at the same time, an obstacle to sustainable land management. This study makes the first-ever analysis of long-term trends in the rate of fragmentation. Our study covers the period from the earliest stages of the current form of ownership patterns at the end of the 18th century until the present day. On the basis of significant predictors that have been identified (initial fragmentation, population growth, historical development of inheritance laws and of the land market, natural soil fertility and landscape type), we go on to project probable developments for the period from 2016 to 2045. A total of 102,984 land parcels in 56 cadastral units in the territory of Czechia have been analysed on the basis of data from four years (1785, 1840, 1950, 2015). Our study considers the development of two basic indicators of fragmentation – Mean Parcel Size and Number of Owners per 100 ha. The Mean Parcel Size has decreased over a period of 230 years from 1.08 ha to 0.64 ha, at a mean rate of −0.26% year−1. During the same period, the Number of Owners per 100 ha has risen from 17.50 to 79.66, at a mean rate of 0.61% year−1. A detailed analysis of the development trends confirms significant spatial variability and also time variability of the rates of the two indicators. The analysis also shows their mutual complementarity: growth in the rate of one of the indicators is usually accompanied by a drop in the other. The general trend that we project for the territory of Czechia in the upcoming 30 years is that there will be further diminution of the physical size of land parcels (continuing fragmentation of land parcels) accompanied by a reduction in the Number of Owners (defragmentation of land ownership).  相似文献   
55.
We assess the degree of market fragmentation in the euro-area corporate bond market by disentangling the determinants of the risk premium paid on bonds at origination. By looking at over 2400 bonds we are able to isolate the country-specific effects which are a suitable indicator of the market fragmentation. We find that, after peaking during the sovereign debt crisis, fragmentation shrank in 2013 and receded to pre-crisis levels only in 2014. However, the low level of estimated market fragmentation is coupled with a still high heterogeneity in actual bond yields, challenging the consistency of the new equilibrium.  相似文献   
56.
In this symposium, we explore how urban citizenship is about expressing, if not producing, difference, and how fragmentation of claims affects urban citizenship and right to the city movements with their universal, all‐inclusive ideals. Investigating social movements, political participation and conflicting diversities in public space in Tel Aviv and Berlin, we see a trend towards a diversification of interests, a weakening of movements, and even a competition over rights and resources rather than a development of mutual support and solidarities among various groups on the pathway to a livable city. This tension, we argue, deserves attention. Radical urban scholarship and politics need to better understand the historical and place‐specific contexts that structure the formation of citizenship claims and the courses that citizenship struggles take. Celebrations of urban citizenship as a more contextualized, community oriented, and bottom‐up framework (in comparison to national citizenship) should therefore be complemented by a careful investigation of their fragmented and fragmenting practices.  相似文献   
57.
微电影广告传播迎合了"碎片化时代"被碎片化的受众对"碎片化"信息的需求,她的繁荣源于政策、技术、市场竞争、受众多方面的原因。微电影广告的传播现状不容乐观,其营销策略主要包括:以人为本,内容为主;注重整合营销;健全监督制度。  相似文献   
58.
鲍万伟 《科技和产业》2022,22(9):308-313
为解决大直径超长钢管柱后插精准定位施工存在的问题,对钢管柱施工定位进行研究。通过采用全回转钻机安放钢套管,起钻进护壁和千斤顶回顶时的支撑作用。针对大直径钢管柱灌注桩身混凝土后插施工,采用在钢管柱中下部设置4个对称的液压千斤顶回顶护壁钢套管,并根据在柱顶实时超声波仪的偏差检测数据,进行定位协同测控调节,达到施工速度快、定位精度高、综合成本低的效果,形成相应的施工技术。  相似文献   
59.
研究目的:探索种植规模对小农户耕地质量保护行为的影响,以及耕地细碎化如何调节种植规模对小农户耕地质量保护行为的影响,以期在“大国小农”的现实语境下为中国耕地污染治理提供理论与经验参考。研究方法:贝叶斯似不相关回归模型、基于遗传算法的倾向得分匹配模型和斜率分析。研究结果:(1)种植规模扩大促进了小农户耕地质量保护行为;(2)耕地细碎化程度的提高不利于小农户保护耕地质量;(3)种植规模扩大对小农户耕地质量保护行为的促进作用,因耕地细碎化的存在而弱化。研究结论:合理推进农村土地互换、有序推动农村土地流转,扩大经营规模、降低耕地细碎化程度,在实现小农户进城与返乡“进可攻、退可守”的同时,促进其耕地质量保护行为。  相似文献   
60.
文章基于中国农地确权制度改革的政策背景,以及备受关注的土地细碎化的资源特征,构建“产权权利界定、产权资源特性与农户生产要素投入”的理论分析框架,借助广东粤北山区阳山县农户的调查数据,采用条件混合处理模型的计量结果表明:农地确权未能有效激励农户的生产要素投入行为,但土地细碎化显著抑制了农户雇佣劳动力和机械服务购买行为,还显著促进了化肥施用。进一步纳入农地确权和土地细碎化的交互项的模型结果表明,农地确权与土地细碎化两者之间不存在互补或替代的交互效应。采用中介机制、子样本分析等模型验证了上述结论的稳健性。由此认为,农地确权政策的影响具有情境依赖性,不可教条式地过度吹捧农地确权政策的生产投入影响效应;对于丘陵山区地带而言,农业政策应从聚焦于地权制度改革调整到缓解农地细碎化问题上。这不仅对激励农业生产要素的投入具有必要性与紧迫性,而且也有利于农地“减肥”,缓解中国日益紧迫的农业资源环境问题。  相似文献   
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