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161.
162.
移动GIS能够弥补传统静态GIS的某些不足,因而正成为地理信息科学领域新的研究热点,而Windows Mobile作为微软进军移动设备领域的主要品牌,受到了人们越来越多的关注。介绍了Windows Mobile操作系统和移动GIS的有关概念,对在Windows Mobile系统上进行移动GIS开发需要解决的几个关键技术,特别是对空间数据建立分块分级索引的技术进行了研究和探讨,最后对系统实现做了有益的尝试。 相似文献
163.
A population’s attitudes toward climate change can strongly influence governmental policies as well as community and individual climate-related behaviors. These attitudes have been explained with a variety of factors, including cultural worldviews, environmental attitudes, political ideology, knowledge of climate change, severe weather exposure, and sociodemographic characteristics. These studies typically assume an individual forms attitudes on the basis of preexisting values or beliefs and do not account for dynamic social interaction as a source of influence. This study introduces a network perspective that accounts for the social embeddedness of individuals, using network variables to predict climate attitudes, including homophily, network strength, attitude diversity, centrality, network size, and network valence. An exploratory factor analysis identified two distinct attitudinal dimensions: climate change epistemic skepticism and belief strength. Using egocentric data from a nationally representative survey collected in 2011, this study found that network variables were significant in predicting both climate attitude dimensions; hierarchical regression analyses accounting for other known predictors found two different predictive models for epistemic skepticism and belief strength. Homophily, network strength, attitude diversity, and network valence predicted epistemic skepticism (R2change = 4.8%), while centrality and network strength predicted belief strength (R2change = 8.9%). The analyses also found support for cultural factors as significant predictors of climate attitudes, particularly Christianity and cultural worldviews. The results of this study suggest that interpersonal influence through communication networks is a promising avenue for continued research, and should be included in studies of climate attitude formation and change. 相似文献
164.
分析了当前石油长输管道日常巡检工作中存在的问题,提出了基于嵌入式GIS技术的输油管道巡检系统原型,用于解决输油管道巡检过程中巡检不到位、设备漏检以及巡检信息传输滞后等方面的问题。介绍了系统的设计目的、组成、工作原理以及关键技术,为嵌入式GIS在输油管道巡检系统中的应用提出了一个可行的方案。 相似文献
165.
运行于Windows Mobile操作系统下的移动GIS,由于其硬件设备的CPU处理速度慢和内存容量小,严重影响其在移动设备上的应用与推广。针对该问题,提出了开发语言的选择、渲染过程的优化控制、数据的内存映射,及各种数据格式的特殊优化处理等措施来提高移动设备上GIS海量数据的渲染性能,并在WindowsMobile平台下通过实际案例的开发研究,实践了这些技术。通过开发实践证明,采用这些技术提高了GIS数据渲染的时间效率和空间效率,方便了用户的操作。 相似文献
166.
This paper investigates trust in the scientists, government authorities and wider risk management team during the ongoing
volcanic crisis in Montserrat, WI. Identifying the most trusted communicator and how trust in information can be enhanced
are considered important for improving the efficacy of volcanic risk communication. Qualitative interviews, participant observations
and a quantitative survey were utilised to investigate the views and attitudes of the public, authorities and scientists.
Trust was found to be dynamic, influenced by political factors made more complex by the colonial nature of Montserrat’s governance
and the changing level of volcanic activity. The scientists were viewed by the authorities as a highly trusted expert source
of volcanic information. Mistrust among some of the local authorities towards the scientists and British Governor was founded
in the uncertainty of the volcanic situation and influenced by differences in levels of acceptable risk and suspicions about
integrity (e.g. as a consequence of employment by the British Government). The public viewed friends and relatives as the
most trusted source for volcanic information. High trust in this source allowed competing messages to reinforce beliefs of
lower risk than were officially being described. The scientists were the second most trusted group by the public and considered
significantly more competent, reliable, caring, fair and open than the authorities. The world press was the least trusted,
preceded closely by the British Governor’s Office and Montserratian Government officials. These results tally well with other
empirical findings suggesting that government ministers and departments are typically distrusted as sources of risk-related
information. These findings have implications for risk communication on Montserrat and other volcanic crises. The importance
and potential effectiveness of scientists as communicators, because of, and despite, the existence of political, cultural
and institutional barriers, is exemplified by this study.
相似文献
Katharine HaynesEmail: Email: |
167.
168.
Hanjiang Xiong Wei Ma Jianya Gong Douadi Abdelalim 《International Journal of Digital Earth》2019,12(5):525-543
Realistic texture mapping and coherent up-to-date rendering is one of the most important issues in indoor 3-D modelling. However, existing texturing approaches are usually performed manually during the modelling process, and cannot accommodate changes in indoor environments occurring after the model was created, resulting in out-dated and misleading texture rendering. In this study, a structured learning-based texture mapping method is proposed for automatic mapping a single still photo from a mobile phone onto an already-constructed indoor 3-D model. The up-to-date texture is captured using a smart phone, and the indoor structural layout is extracted by incorporating per-pixel segmentation in the FCN algorithm and the line constraints into a structured learning algorithm. This enables real-time texture mapping according to parts of the model, based on the structural layout. Furthermore, the rough camera pose is estimated by pedestrian dead reckoning (PDR) and map information to determine where to map the texture. The experimental results presented in this paper demonstrate that our approach can achieve accurate fusion of 3-D triangular meshes with 2-D single images, achieving low-cost and automatic indoor texture updating. Based on this fusion approach, users can have a better experience in virtual indoor3-D applications. 相似文献
169.
观测控制系统是当前的一个研究热点,底层通信是观测控制系统架构的一个重要环节。但传统的观测控制系统一般采用裸套接技术实现,缺少统一的传输控制机制,在密集数据通信时经常存在延迟,影响实时控制的需要;同时缺少广播与组播机制,限制了观测控制系统的设计。针对观测控制系统的要求,研究了基于ZeroMQ不同通信模型及对应的天文控制模式,分析了不同的通信控制架构的可用性,在此基础上通过实验对相应的通信模型进行测试,验证其在天文仪器分布控制中的可用性。测试结果进一步说明,ZeroMQ构建观测控制系统的底层通信架构是可行的,能够满足观测控制系统对设备的各种控制需求。 相似文献
170.
1INTRODUCTIONHumanactivitiesmayinducesignificantchangesinsedimenttransportcapacityofaluvialriverchannelsandcausechangesinthe... 相似文献