Western Canadian dairy farmers' perspectives on the provision of outdoor access for dairy cows and on the perceptions of other stakeholders

The provision of pasture and outdoor access for dairy cattle differs around the globe. For example, in Ireland, New Zealand, and Australia, dairy farms are largely pasture based, whereas dairy farms in the United States and Canada are largely confinement based. There is a high level of public support for pasture and outdoor access for dairy cows, and the available evidence shows that dairy cattle are highly motivated to access pasture, especially at night. The decision as to whether to provide outdoor access is typically made by farmers, but little is known about dairy farmers' perspectives on this topic. We investigated perspectives of Western Canadian dairy farmers on outdoor access, as well as how they believe different stakeholders (i.e., the dairy industry, the dairy cows, and the general public) regard outdoor access for dairy cows. Data were collected via (1) 11 focus group discussions with a total of 50 Western Canadian dairy farmers, and (2) semi-structured individual interviews with an additional 6 dairy farmers of Hutterite colonies. Data were analyzed using template analysis. Although most participants in this study did not provide outdoor access on their farms, or only provided outdoor access to certain cow groups, participants generally mentioned that they enjoyed seeing cows on pasture or outdoors. However, participants shared that the Canadian supply management system (including processors) required a consistent flow of production, which was thought to be easier and more economically realized with indoor housing of lactating cows. Participants believed that pasture or outdoor access for dairy cows was desired by the public. Some participants believed that dairy cows prefer to spend time outside under favorable weather conditions, but others felt that cows preferred to stay indoors in modern, ventilated freestall barns. The results of this study describe the perspectives of dairy farmers regarding the views of dairy industry stakeholders as they relate to outdoor access, helping to inform conversations around the provision of outdoor access for dairy cattle.     

基于多视图立体视觉的沙堆三维尺寸测量研究

利用从运动中恢复结构方法(SFM),提出了一种基于多视图立体视觉的沙堆三维重建及三维尺寸测量方法。首先根据SFM方法的求解不稳定特点,结合光束平差法对SFM求解过程进行分析及优化;其次针对SFM重建结果为稀疏点云的问题,利用基于面片的稠密重建算法重新生成稠密的三维点云,再利用泊松算法对密集点云进行三维曲面重建;最后获得模型的三维尺寸信息。对某建筑工地的沙堆进行了三维尺寸的测量实验,实验结果验证了该方法的有效及可行性,提高了重建能力及精度,同时考虑了目标实际测量误差与重建误差,能够满足实际智能测量的应用需求。     

从中西色彩观差异看中西方设计色彩的异与同

目的对中西方设计色彩差异进行理论分析。方法以中西色彩表达的文化差异为基础,通过对中西方色彩观的文化渊源进行比较分析,提炼出对中西传统色彩观的文化特点概括。结论通过对色彩在中西方建筑、服饰、装饰等设计中的运用案例进行分析,把握传统色彩观在历史空间中的演进与中西融合趋势,以求对21世纪全球语境下的现代设计色彩发展,提供基于中西传统色彩观特点比较分析基础上的把握。     

基于街景地图数据的北京市东城区 街道绿色空间正义评估研究

绿色空间正义是城市空间正义的典型代表，意为在人群中公平分配维护绿色空间的责任和享有绿色空间的权益。根据其定义，以北京市东城区为例，从责任和权益2个角度着眼，一方面基于百度街景地图数据提炼街道空间绿视率的空间分布特点，表征街道绿色空间的客观可感知水平；另一方面将街道绿视率和实时人口热力叠加，探讨街道绿色空间的实际被感知程度，从而完成对北京市东城区街道绿色空间维护和享有情况的评估。发现邻近使用者维护街道绿色空间的责任对绿化客观可感知水平的重要性，以及合理的道路断面设计对同时提升街道空间活力和绿视率即绿化实际被感知程度的有效性。由此总结出2点街道绿色空间规划设计建议，即明晰权责边界并保证公共权益优先级，以及加强落地性设计导则中对绿色空间正义问题的关注，并对未来研究提出展望。     

Social licence: power imbalances and levels of consciousness – two case studies

ABSTRACT

Social licence to operate (SLO) is a term that is finding increasing acceptance in a number of industries. Like all new terms, its precise meaning and implications are still being investigated. Using data from previous studies, this paper offers an analysis of the SLO of two case studies with each study being viewed separately through the grid of a distinct theoretical framework. Case study 1 looks at the development of differential social licence negotiated in the Hamlet of Cambridge Bay, Nunavut, as a result of an impact and benefit agreement negotiated between Tahera Diamond Corp. and the Kitikmeot Inuit Organisation in 2004. The study demonstrates that general acceptance of resource development can be uneven and reflect an unequal distribution of decision-making power. In case study 2, stakeholders of a failed mineral development project were queried across time about the specifics of the proposed mine development and were queried about resource development across different levels of consciousness. Perhaps, SLO is variable across different levels of consciousness. The paper concludes with observations about the variable nature of SLO acceptance across populations and across levels of consciousness within individuals. Perhaps, the concept of SLO is, in fact, complex, difficult to define and measure and, at this point, of limited utility as a measure of resource development acceptance.     

Waveguide-based near-eye display with dual-channel exit pupil expander

We propose a waveguide-based near-eye display featuring a dual-channel exit pupil expander, which is composed of an in-coupler, relay gratings, and an out-coupler. Unlike the conventional waveguide-based near-eye displays, whose field of views are usually non-split or partially split, our dual-channel exit pupil expander is able to evenly split the field of view into two halves. The greatest benefit of doing so is that the upper limit of field of view could be significantly increased. The design rules for all components, including the microdisplay, collimating lens, waveguide and gratings, have been studied. The refractive index and dimension of waveguide are identified as two factors that limit the field of view. In what follows, its key specifications are recapitulated. Field of view is 70° (diagonal), eye relief is 15 mm, exit pupil is 20 × 9 mm², modulation transfer function is above 0.591 at 30 cycle/degree, contrast ratio is 13, and distortion is 1.38%.     

德国科隆足球体育场

人们从北侧进入体育场。入口以玻璃屋顶覆盖。四条主要的流线环形配置在看台下,各自独立。体育场有四万五千个屋顶覆盖的坐位,而且提供无柱遮挡的视野。     

浅谈绿色建筑

对绿色建筑的概念进行了阐述，并分析其与生态建筑、可持续建筑之间的关系，对绿色建筑的来源进行了论述，通过研究绿色建筑中的生态观，说明绿色建筑观的重要性与必要性。     

新时代呼唤新的建筑美学──就当下建筑、空间环境问题访中国后现代研究所所长李正天

世界是一个立体的太极球，以美国为代表的西方文明是一种阳性文明，加州则是阳性文明的阴点；以中国为代表的东方文明是一种阴性文明，广东则是阴性文明的阳点，两大文明相互激活，相互补充，定能够造就一种全新的文明。     

混凝土结构耐久性的整体论

从分解论而不是从整体论角度研究混凝土耐久性，对改善混凝土结构的耐久性是事倍功半，甚至是无济于事的。国内混凝土结构过早劣化的起因是微裂缝和孔隙的存在。改善混凝土的匀质性，减少或避免混凝土早期开裂，才能获得延长结构服务寿命的整体效果。