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51.
车牌定位是车牌识别系统中的关键技术之一,车牌定位的质量直接影响着后续字符识别的结果。本文提出了一种结合投影法和形态学的车牌定位算法,首先对图像进行预处理,接着利用水平投影算法确定车牌的上下边界,然后利用形态学方法迭代确定车牌的左右边界.最后进行精定位。实验表明,该方法具有较高的定位精度。  相似文献   
52.
Governance failures are at the origin of many resource management problems. In particular climate change and the concomitant increase of extreme weather events has exposed the inability of current governance regimes to deal with present and future challenges. Still our knowledge about resource governance regimes and how they change is quite limited. This paper develops a conceptual framework addressing the dynamics and adaptive capacity of resource governance regimes as multi-level learning processes. The influence of formal and informal institutions, the role of state and non-state actors, the nature of multi-level interactions and the relative importance of bureaucratic hierarchies, markets and networks are identified as major structural characteristics of governance regimes. Change is conceptualized as social and societal learning that proceeds in a stepwise fashion moving from single to double to triple loop learning. Informal networks are considered to play a crucial role in such learning processes. The framework supports flexible and context sensitive analysis without being case study specific.First empirical evidence from water governance supports the assumptions made on the dynamics of governance regimes and the usefulness of the chosen approach. More complex and diverse governance regimes have a higher adaptive capacity. However, it is still an open question how to overcome the state of single-loop learning that seem to characterize many attempts to adapt to climate change. Only further development and application of shared conceptual frameworks taking into account the real complexity of governance regimes can generate the knowledge base needed to advance current understanding to a state that allows giving meaningful policy advice.  相似文献   
53.
Greater recognition of the seriousness of global environmental change has led to an increase in research that assesses the vulnerability of households, communities and regions to changing environmental or economic conditions. So far, however, there has been relatively little attention given to how assessments can be conducted in ways that help build capacity for local communities to understand and find their own solutions to their problems. This paper reports on an approach that was designed and used to work with a local grass roots organization in the Solomon Islands to promote inclusivity and participation in decision-making and to build the capacity of the organization to reduce the vulnerability of communities to drivers of change. The process involved working collaboratively with the organization and training its members to conduct vulnerability assessments with communities using participatory and deliberative methods. To make best use of the learning opportunities provided by the research process, specific periods for formal reflection were incorporated for the three key stakeholders involved: the primary researchers; research assistants; and community members. Overall, the approach: (1) promoted learning about the current situation in Kahua and encouraged deeper analysis of problems; (2) built capacity for communities to manage the challenges they were facing; and (3) fostered local ownership and responsibility for problems and set precedents for future participation in decision-making. While the local organization and the communities it serves still face significant challenges, the research approach set the scene for greater local participation and effort to maintain and enhance livelihoods and wellbeing. The outcomes highlight the need for greater emphasis on embedding participatory approaches in vulnerability assessments for communities to benefit fully from the process.  相似文献   
54.
Vulnerability of Aboriginal health systems in Canada to climate change   总被引:1,自引:0,他引:1  
Climate change has been identified as potentially the biggest health threat of the 21st century. Canada in general has a well developed public health system and low burden of health which will moderate vulnerability. However, there is significant heterogeneity in health outcomes, and health inequality is particularly pronounced among Aboriginal Canadians. Intervention is needed to prevent, prepare for, and manage climate change effects on Aboriginal health but is constrained by a limited understanding of vulnerability and its determinants. Despite limited research on climate change and Aboriginal health, however, there is a well established literature on Aboriginal health outcomes, determinants, and trends in Canada; characteristics that will determine vulnerability to climate change. In this paper we systematically review this literature, using a vulnerability framework to identify the broad level factors constraining adaptive capacity and increasing sensitivity to climate change. Determinants identified include: poverty, technological capacity constraints, socio-political values and inequality, institutional capacity challenges, and information deficit. The magnitude and nature of these determinants will be distributed unevenly within and between Aboriginal populations necessitating place-based and regional level studies to examine how these broad factors will affect vulnerability at lower levels. The study also supports the need for collaboration across all sectors and levels of government, open and meaningful dialogue between policy makers, scientists, health professionals, and Aboriginal communities, and capacity building at a local level, to plan for climate change. Ultimately, however, efforts to reduce the vulnerability of Aboriginal Canadians to climate change and intervene to prevent, reduce, and manage climate-sensitive health outcomes, will fail unless the broader determinants of socio-economic and health inequality are addressed.  相似文献   
55.
Research on place attachments and identities has made an important contribution to understanding social acceptance of low carbon infrastructure, which are often objected to by local communities. However, a focus on local attachments predominates in studies to date, neglecting the potential role of national and global attachments and identities on energy beliefs and attitudes, despite the fact that large energy infrastructures are not only local in significance or function. To investigate this, survey data was collected from a representative sample of UK adults (N = 1519), capturing place attachments at local, national and global levels, climate change concern, beliefs about power lines and support for energy system change. Findings show significant differences in infrastructure beliefs and attitudes depending upon relative strength of attachments at different levels, controlling for personal characteristics. Analyses of variance revealed that individuals with stronger national than local or global attachments were less likely to support European grid integration; those with relatively stronger global attachment were most likely to support decentralised energy and those with relatively stronger local attachment were most likely to protest against a nearby power line. In addition, those with strong attachments at local, national and global levels were most willing to reduce energy demand, and those with weak attachments were least likely to trust grid companies. Relatively stronger global than national attachment was positively associated with support for decentralised energy, with this effect partially mediated by climate change concern. Explanations for the findings and implications for future research are discussed.  相似文献   
56.
Communities living in the grasslands of present day Inner Mongolia have experienced dramatic social, economic and ecological changes over the past millennium. More recently, these grasslands have undergone widespread degradation, raising concern for securing local herders' livelihoods. To understand these changes in ecological and welfare outcomes over long time scales, we define five broad periods of relative institutional stability over the past millennium, characterize social-ecological system during each period, and then assess major changes between these periods. Looking at changes in institutional contexts helps explain some of our outcomes of interest. We find that while much attention has been given to the change in grassland lease structures in China, the role of market integration and buffers against historically natural constraints on livestock production (e.g., protection from the winter months) have decoupled formerly tight local social-ecological links. This decoupling, along with weak land tenure security due to a complex and volatile policy landscape, suppresses local incentives for grassland conservation.  相似文献   
57.
We present a unique and transparent approach for incorporating social influence effects into global integrated assessment models used to analyse climate change mitigation. We draw conceptually on Rogers (2003) diffusion of innovations, introducing heterogeneous and interconnected consumers who vary in their aversion to new technologies. Focussing on vehicle choice, we conduct novel empirical research to parameterise consumer risk aversion and how this is shaped by social and cultural influences. We find robust evidence for social influence effects, and variation between countries as a function of cultural differences. We then formulate an approach to modelling social influence which is implementable in both simulation and optimisation-type models. We use two global integrated assessment models (IMAGE and MESSAGE) to analyse four scenarios that introduce social influence and cultural differences between regions. These scenarios allow us to explore the interactions between consumer preferences and social influence. We find that incorporating social influence effects into global models accelerates the early deployment of electric vehicles and stimulates more widespread deployment across adopter groups. Incorporating cultural variation leads to significant differences in deployment between culturally divergent regions such as the USA and China. Our analysis significantly extends the ability of global integrated assessment models to provide policy-relevant analysis grounded in real world processes.  相似文献   
58.
Green infrastructure has recently risen to international prominence for its purported capacity to enhance urban sustainability, and particularly to modulate ambient temperatures in the context of climate change. We assess whether residents in a sub-tropical Australian city perceive green infrastructure as an effective climate adaptation response for reducing vulnerability to heat stress. Gold Coast City has pursued urban densification policies, such as reducing block sizes and increasing building heights, to accommodate rapid population growth. Little attention has been given to the combined impact of local heat island effects and global climate change upon lower-income residents in the city's suburban fringe, including rising energy costs associated with cooling homes. The study has three aims: to assess whether social disadvantage is associated with (1) concern about climate change impacts; (2) perceptions about the potential of green infrastructure to offer potential climate-adaptive benefits; and (3) the desire for more urban greening in a working class suburb. We used a mail-back survey to elicit information related to cooling dwellings, awareness of, and concern about, climate change impacts, perceptions of the benefits of green infrastructure, and desire for more urban greening. Results indicate that despite their vulnerability to heat stress, comparatively disadvantaged residents are no more concerned about climate change; nor are they any more inclined to encourage local government to enhance neighbourhood greenery. These residents are, if anything, less likely to perceive benefits of urban greening. Our findings indicate that cultivating support for green infrastructure in disadvantaged neighbourhoods will require parallel efforts to redress inequality.  相似文献   
59.
基于SNA的新型集中社区公共空间网络结构优化   总被引:2,自引:2,他引:0  
公共空间并非“存在即合理”。公共空间网络结构效率折射出社会网络的重构能力、社会资本的建构强度、社会秩序的重塑能力。新型集中社区作为近年大量涌现的新型居住形态,正面临社会关系重构的巨大压力。本文运用社会学的网络分析法研究公共空间网络,并对苏州新型集中社区D的公共空间网络结构进行实证分析,其结论为:公共空间网络的关联度为0.216、中心势0.358、小世界值1.978,表明空间网络整体关联度不足,呈现出破碎化的特征;商业空间整合效应的发挥受到业态配置的影响;居民社会属性对空间网络结构特征造成一定影响。最后,基于“社会—空间”互动逻辑,以社会网络重构为导向,从集中安置模式、公共空间网络优化2个层面,提出新型集中社区有待进一步研究的方向,以期为当前及未来的集中社区规划建设和公共空间整体优化提供科学合理的依据。  相似文献   
60.
退化土地的生态重建:社会工程途径   总被引:73,自引:5,他引:68  
蔡运龙  蒙吉军 《地理科学》1999,19(3):198-204
土地退化是全球环境变化的主要表现之一,而且与贫困问题互为因果。中国各地土地退化类型中,分布最广、影响最大的是土地沙漠化和土壤侵蚀,连片贫困人口也就分布于这些地区。在人口增长和自然资源需求增加的压力下,让退化土地自然恢复的思路已不切实际,必须通过社会投入对退化土地进行生态重建。重建要医治引起土地退化的经济和社会病根。还需要发达地区和欠发达地区的共同努力,因而是一种社会工程。其途径包括:从满足人民生存  相似文献   
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