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21.
由于人类体验自然的渴望日益增长,在政治和实践层面,在城市中提供接触自然的机会显得越来越必要。关于“城市荒野”的思想和规划旨在提供一种特殊的自然体验。鉴于不同荒野思想之间存在冲突,风景园林师必须设法了解已有的荒野认知及其含义。通过 3 个荒野类别—“未知荒野”“特定荒野”和“过程荒野”,探讨发展千年的荒野理念,并提出“殖民化”(colonisations)概念作为理解荒野理念发展的一个关键。自然过程伴随着动植物对空间的殖民,而人类进入和占有空间的殖民过程则包含生理、心理和精神 3 个层面的内容。空间命名是一种特殊的、具有精神和象征意味的殖民化形式。例如,人类在城市中发现野生植被,称其为“野性自然”或“城市荒野”。然而,如今大多数(尤其官方)的荒野定义中均排除了人类干扰:一旦被殖民,真正的荒野就不复存在。科学研究对自然过程的殖民化已取得很多成果,但对于人类有关自然和荒野的认知和态度了解并不多。对于风景园林师来说,这有助于更好地理解如何“基于自然进行设计和建造”,对创造令人满意的景观也非常重要。探讨与“城市荒野”有关的论述、规划和设计观点及思想。 由于人类体验自然的渴望日益增长,在政治和实践层面,在城市中提供接触自然的机会显得越来越必要。关于“城市荒野”的思想和规划旨在提供一种特殊的自然体验。鉴于不同荒野思想之间存在冲突,风景园林师必须设法了解已有的荒野认知及其含义。通过 3 个荒野类别—“未知荒野”“特定荒野”和“过程荒野”,探讨发展千年的荒野理念,并提出“殖民化”(colonisations)概念作为理解荒野理念发展的一个关键。自然过程伴随着动植物对空间的殖民,而人类进入和占有空间的殖民过程则包含生理、心理和精神 3 个层面的内容。空间命名是一种特殊的、具有精神和象征意味的殖民化形式。例如,人类在城市中发现野生植被,称其为“野性自然”或“城市荒野”。然而,如今大多数(尤其官方)的荒野定义中均排除了人类干扰:一旦被殖民,真正的荒野就不复存在。科学研究对自然过程的殖民化已取得很多成果,但对于人类有关自然和荒野的认知和态度了解并不多。对于风景园林师来说,这有助于更好地理解如何“基于自然进行设计和建造”,对创造令人满意的景观也非常重要。探讨与“城市荒野”有关的论述、规划和设计观点及思想。 相似文献
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The mismatch of transmission ability causes the discontinuous transmission of video services in fiber-wireless access network,aimed at this problem,an QoE-aware video distribution mechanism was proposed.According to the structural characteristics of fiber-wireless access network,link state information and scalable video coding structure was considered,a QoE evaluation mode was established,and the particle swarm optimization algorithm was used to select optimal video transmission rate.Then the node transmission capacity and the node matching degree was analyzed,transmission path for the services was selected,so as to ensure the reliable transmission of services.The results show that the proposed mechanism can effectively improve the utilization rate of network resources and reduce network congestion while improving the quality of the user experience. 相似文献
24.
为解决4GVoLTE语音业务过程中出现的用户时延增大、MOS值下降、体验变差的问题。通过对SR配置及调度策略的优化、AMC算法优化、SPS调度策略优化等,采用理论仿真和实际测试相结合的方法,验证算法优化前后对系统性能及用户体验的改善效果。本文提出的优化策略一方面保证了VoLTE业务的优先级,另一方面兼顾了VoLTE业务的空口质量,可有效缩短VoLTE业务时延,降低VoLTE业务的空口丢包率,增加基站VoLTE容量,最终达到提升语音质量和用户体验的目的。 相似文献
25.
《Journal of Visual Communication and Image Representation》2014,25(3):542-554
In this paper, we study the impact of quantization, frame dropping and spatial down-sampling on the perceived quality of compressed video streams. Based on the analysis of quality ratings obtained from extensive subjective tests, we propose a no-reference metric (named MDVQM) for video quality estimation in the presence of both spatial and temporal quality impairments. The proposed metric is based on the per-pixel bitrate of the encoded stream and selected spatial and temporal activity measures extracted from the video content. All the values required to compute the proposed video quality metric can be obtained without using the original reference video which makes the metric for instance useful for making transcoding decisions in a wireless video transmission scenario. Different from comparable metrics in the literature, we have also considered the case when both frame rate and frame size are changed simultaneously. The validation results show that the proposed metric provides more accurate estimation of the video quality than the state of the art metrics. 相似文献
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This paper represents an effort to investigate the impact of perceived new media credibility on citizens’ online political efficacy (OPE) in new democracies. Unlike their counterparts in mature democracies and outright authoritarian states, citizens of new democracies face the challenge to reconcile their democratic present with the authoritarian past. Their online political behaviors therefore are likely to be shaped by the interaction between democratic realities and authoritarian legacies or memories. The current study argues that in new democracies, the relationship between credibility of new media and OPE is contingent upon citizens’ authoritarian experience. Since authoritarian experience delivers a sense of relative acquisition through a comparison mechanism, it is expected to play a positive role in moderating the association between credibility of new media and OPE. We test the proposition by studying a sample of Taiwanese residents interviewed during the 2015 Taiwan Communication Survey (TCS). Our empirical analyses produce strong supportive evidence for the positive conditioning effect of authoritarian experience and the result is robust to different model specifications and alternative measures of authoritarian experience. 相似文献
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With the rapid growth and popularity of Social Streaming Apps (SSAs) worldwide, it is valuable for scholars to understand the links between immersive experience provided by SSA, users’ attitudes towards SSA, and the resultant SSA dependency. Although unexplored in the SSA context, previous research has indicated the significance of immersive experience and its influence on user’s specific behavior through user attitude. The present study employs Structural Equation Modelling, by using 459 samples from a survey, to explore how the intensity of immersive experience can influence the degree of user dependency on SSA. Results indicate that immersive experience is positively associated with users’ positive attitudes towards SSA, which would lead to SSA dependency. In addition, this study also found out that users’ favorable attitude partially mediates the relationship between immersive experience and solitary play dependency. Whereas, attitude fully mediated the relationship between five out of six dimensions of SSA dependency. Furthermore, to better comprehend the intervening relationships between immersive experiences, user attitude, SSA dependency, the study also conducted a moderation analysis taking frequency of use as a moderating variable. The results illustrate that a high frequency of use is a strong psychological indicator for SSA dependency. This supports the importance of considering actual behavior along with their psychological states when examining users’ immersive experience and their SSA dependency. 相似文献
30.