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1.
A longstanding challenge in additive manufacturing (AM), the presence of void regions in additively manufactured components, causes two main issues: the enclosing of build material powder in powder bed fusion techniques and limiting tool access in critical post-processing operations to remove sacrificial support structures. As topology optimization has embraced and overcome many of the obstacles of incorporating AM constraints into the underlying numerical optimization statement, there exist few solutions that directly address this fundamental void region issue. By developing computationally efficient and effective solutions to this problem, the integration of these two advanced technologies can be fully realized. Drawing on inspiration from the principles of diffusion physics, a particle diffusion void restriction (PDVR) method is presented in this work that is capable of encouraging the optimization scheme to generate final designs that are fully accessible. Additionally, this method empowers the user to choose the type of post-processing method to clear support material (eg, three-axis or five-axis milling operations, number and orientation of part set-ups) and, therefore, quantify the level of costs associated with the post-processing operation. The PDVR optimization framework is demonstrated on multiple two- and three-dimensional test problems, with physically manufactured examples depicting the real-world benefits this method admits.  相似文献   
2.
A recent development in tactile technology enables an improvement in the appreciation of the visual arts for people with visual impairment (PVI). The tactile sense, in conjunction with, or a possibly as an alternative to, the auditory sense, would allow PVIs to approach artwork in a more self‐driven and engaging way that would be difficult to achieve with just an auditory stimulus. Tactile colour pictograms (TCPs), which are raised geometric patterns, are ideographic characters that are designed to enable PVIs to identify colours and interpret information by touch. In this article, three TCPs are introduced to code colours in the Munsell colour system. Each colour pattern consists of a basic cell size of 10 mm × 10 mm to represent the patterns consistently in terms of regular shape. Each TCP consists of basic geometric patterns that are combined to create primary, secondary, and tertiary colour pictograms of shapes indicating colour hue, intensity and lightness. Each TCP represents 29 colours including six hues; they were then further expanded to represent 53 colours. Two of them did not increase the cell size, the other increased the cell size 1.5 times for some colours, such as yellow‐orange, yellow, blue, and blue‐purple. Our proposed TCPs use a slightly larger cell size compared to most tactile patterns currently used to indicate colour, but code for more colours. With user experience and identification tests, conducted with 23 visually impaired adults, the effectiveness of the TCPs suggests that they were helpful for the participants.  相似文献   
3.
交通区位与交通基础设施条件是影响大型体育场馆是否成功建设运营的重要因素。在交通网络多样化复杂化的发展背景下,更精准认知把握交通设计条件是进行场馆规划选址、新场馆建设策划旧场馆改造等活动的重要基础。基于已有可达性理论基础上,探讨大中型体育场馆定位与交通可达性之间的关联性。并尝试构建大型体育场馆交通可达性量化分析模型,实现对大中型场馆交通可达性的定量认知。最后以广佛地区为例选取拟建三水区体育场及周边多个场馆,应用该量化方法,并将分析结果作为参考依据之一用于拟建三水体育场规模与功能定位的决策工作。  相似文献   
4.
大数据为风景园林规划方法的创新提供了技术支持,为城市公园游憩使用和规划应对带来了新的机遇。首先,对城市公园游憩使用研究中有关大数据的应用类型进行梳理和分类;其次,从公园游憩使用、可达性、服务范围和规划应对4个方面分析城市公园游憩使用的研究进展;最后对城市公园游憩使用研究方法进行分类总结。在游憩使用方面,大数据可通过游人分布特征判定公园游憩使用情况;在可达性方面,大数据用于精细化分析不同尺度的城市公园的可达性,促进公园规划的合理性;在服务范围方面,大数据可用于城市公园服务范围的识别、基于流动进行衰退研究,提高公园游憩规划的公平性;在规划应对方面,可通过研究游憩使用的影响因素进一步指导规划。同时对大数据在游憩使用研究方面的未来发展趋势做出判断,以期为大数据在公园游憩规划中得以更好的应用提供合理思路。  相似文献   
5.
具备可进入的绿色空间、游乐场地是儿童友好城市衡量中的核心指标,也是城市公园提供的必要服务之一。聚焦对城市公园需求度和使用率较高的学龄前儿童,尝试建构综合考虑城市公园品质和可达性的分析及评估方法。选取联合国儿童友好城市——西班牙巴塞罗那为案例,基于实地调研、开源地图、官方统计数据等,使用儿童友好的公园品质指数(QUINPY)和空间句法可达性模型开展综合评价,并结合学龄前儿童人口密度分布,提出有针对性的改善建议,基于不同的需求和现状,选取改善城市交通步行环境、合理增加结构性设施或者鼓励分时段及立体化拓展空间使用可能性等适宜性创新措施。以期为我国儿童友好导向的城市公园发展建设提供参考。  相似文献   
6.
摘要 地铁站作为城市重要的交通节点,在发达城市商业中心区的站点多与周边商业建筑地下空间相互连通,为城市 核心商业区输送大量的步行人流,从而带来更多商业机遇。选取我国典型中心商业区地铁开发模式的广州北京路商圈 及其附近的公园前地铁站为例,通过实地调研测量统计步行人流量、轨迹等数据,运用行为模拟、空间分析等方法, 讨论公园前地铁站域的地下空间建设对北京路商圈地面人流的再分配作用,进而分析地铁站各地面出入口的商业表现、 服务范围与功能,对该站点建设之于商业发展的促进作用做出初步评估。通过对公园前地铁站域以及其主要服务的北 京路商业区的案例深入解读,希望为其他城市传统中心商业区的站点交通发展或新开发提供借鉴。  相似文献   
7.
Territorial Impact Assessment (TIA) is proposed as a critical tool in order to investigate the way policies affect spatial development and hence territorial cohesion. The paper introduces a TIA methodological model in relation to transport sector. The design of the methodological model is based on a quantitative evaluation framework that comprises a set of selected indicators applied in a cross-border area of southeast Europe, influenced by the operation of the Greek motorway system of Egnatia and its vertical axes. The indicators are grouped into three main fields of TIA, i.e. transport intermodality, polycentric spatial organization and cross-border territorial cooperation. The TIA’s indicators are approximated by quantitative analysis. The procedure concludes to an overall composite indicator measuring the ‘level of territorial cohesion’ along with some core results and the expected added value. It also highlights some key technical aspects about the routines used and proceeds to suggestions for further refinement.  相似文献   
8.
包瑞清   《风景园林》2022,29(6):103-108
公共交通出行方式下,综合性公园的可达性及配置的均衡性是评价城市公园绿地配置和本地居民享有公共服务设施权利的重要指标。以南京市为例,建立公共交通复合网络,以时间成本距离分析综合性公园服务的区域水平和基于站点位置的可达性;以基尼系数判断全局和15分钟生活圈下综合性公园分布的均衡性及贡献度;建立新公园选址采样点,分析增加新公园选址后的基尼系数变化的空间分布。结果表明:以可达性为前提,以基尼系数为衡量指标,可以量化分析公园分布均衡性,通过基尼系数更新变化的空间分布,可以明确新规划公园对综合性公园分布均衡性的影响,能够确定优化选址区域。为城市新综合性公园规划提供量化的区域范围参考,优化城市公园布局并提高城市公园可达性和分布均衡性。  相似文献   
9.
We report an optimized low‐input FAIRE‐seq (Formaldehyde‐Assisted Isolation of Regulatory Elements‐sequencing) procedure to assay chromatin accessibility from limited amounts of yeast cells. We demonstrate that the method performs well on as little as 4 mg of cells scraped directly from a few colonies. Sensitivity, specificity and reproducibility of the scaled‐down method are comparable with those of regular, higher input amounts, and allow the use of 100‐fold fewer cells than existing procedures. The method enables epigenetic analysis of chromatin structure without the need for cell multiplication of exponentially growing cells in liquid culture, thus opening the possibility of studying colony cell subpopulations, or those that can be isolated directly from environmental samples.  相似文献   
10.
Accessibility of public health websites allows important information to reach as many audiences as possible. This is vital during a public health crisis such as the current COVID-19 pandemic. This paper reviews public health information portals provided by the Australian Capital Territory local government against the Web Content Accessibility Guidelines.  相似文献   
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