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91.
This study highlights how heuristic evaluation as a usability evaluation method can feed into current building design practice to conform to universal design principles. It provides a definition of universal usability that is applicable to an architectural design context. It takes the seven universal design principles as a set of heuristics and applies an iterative sequence of heuristic evaluation in a shopping mall, aiming to achieve a cost-effective evaluation process. The evaluation was composed of three consecutive sessions. First, five evaluators from different professions were interviewed regarding the construction drawings in terms of universal design principles. Then, each evaluator was asked to perform the predefined task scenarios. In subsequent interviews, the evaluators were asked to re-analyze the construction drawings. The results showed that heuristic evaluation could successfully integrate universal usability into current building design practice in two ways: (i) it promoted an iterative evaluation process combined with multi-sessions rather than relying on one evaluator and on one evaluation session to find the maximum number of usability problems, and (ii) it highlighted the necessity of an interdisciplinary ad hoc committee regarding the heuristic abilities of each profession. A multi-session and interdisciplinary heuristic evaluation method can save both the project budget and the required time, while ensuring a reduced error rate for the universal usage of the built environments.  相似文献   
92.
In this paper, effects of the implant thread pitch on the maximum Von Mises stresses were evaluated in jaw bones and implant–abutment complex by a finite element method. The thread pitch ranged from 0.5 mm to 1.6 mm. Results suggested that under axial load, the maximum equivalent stresses in cortical bone, cancellous bone and implant–abutment complex decreased by 6.7%, 55.2% and 22.3%, respectively with the variation of thread pitch; and under buccolingual load, 2.7%, 22.4% and 13.0%, respectively. When thread pitch exceeded 0.8 mm, minimum stresses were obtained. Data indicated that cancellous bone was more sensitive to thread pitch than cortical bone did; thread pitch played a great role in protecting dental implant under axial load than under buccolingual load; and thread pitch exceeding 0.8 mm were optimal selection for a screwed implant by biomechanical consideration.  相似文献   
93.
ABSTRACT

This article serves as an introduction to a special issue of the journal Digital Creativity, which addresses the challenges, potentials and meaning of different creative forms of citizenship enacted through social media. The articles in this special issue paint a complex picture of the expressions and meaning and citizenship. This introduction aims to provide a wider context for the contributions to this special issue by reviewing some of the claims made for the creative civic potential of social media and identifying a number of issues and questions that might inform analyses of the subject.  相似文献   
94.
The stress and strain fields around the crack tip for power hardening material, which are singular as r approaches zero, are crucial to fracture and fatigue of structures. To simulate effectively the strain and stress around the crack tip, we develop a seven-node singular element which has a displacement field containing the HRR term and the second order term. The novel singular element is formulated based on the edge-based smoothed finite element method (ES-FEM). With one layer of these singular elements around the crack tip, the ES-FEM works very well for simulating plasticity around the crack tip based on the small strain formulation. Two examples are presented with detailed comparison with other methods. It is found that the results of the presented singular ES-FEM are closer to reference solution, which demonstrates the applicability and the effectiveness of our method for the plastic field around the crack tip.  相似文献   
95.
To understand the building design process and to help designers involved, the idea of a research engine has been developed: In this engine cyclic transformations take place between spatial and structural building designs. With this engine, a design process can be studied closely and subjected to improvement, and designers can be supported. To develop the engine, in this paper a part of it is studied, namely the transformation from spatial to structural design, which can be divided into four sub transformations: (1) from spatial design to structural topology; (2) from structural topology to mechanical model; (3) from mechanical model to finite element model; (4) from finite element model to design recommendations. For the first sub transformation, two different techniques are presented: Spatial–Structural Transformation Rules and Element Selection. For the second sub transformation, also two techniques are presented: Element Approach and System Approach. Where possible, data models in EXPRESS and process models in IDEF0 are used. For the third and fourth sub transformation, new procedures have been developed using data models in EXPRESS. To test the data and process models for all four sub transformations, a simplified two-storey building, derived from a real six-storey apartment building, is used as case study. It can be concluded that the developed sub transformations function well, related to their application in the research engine, and that their development raises new research questions that have to be solved in the near future.  相似文献   
96.
西藏地区太阳能采暖建筑热工性能优化研究   总被引:1,自引:1,他引:0       下载免费PDF全文
西藏地区太阳能资源非常丰富且冬季温度低,该地区非常适合大面积推广太阳能采暖系统,以达到节能减排的目的。但是由于实际大部分太阳能采暖工程,忽略了建筑围护对太阳能主动式采暖系统初投资与运行费用的影响,造成了太阳能主动式采暖系统初投资过高、太阳能保证率低。为了分析建筑热工性能对太阳能主动式采暖系统的影响,笔者利用数值模拟方法,将建筑热工性能与主动式太阳能采暖系统作为一个整体进行计算分析,利用初投资费用最低与全寿命周期总费用最低两个目标函数,对主动式太阳能采暖建筑热工性能的保温性能进行优化。结果表明,提高建筑围护结构热工性能,不仅可以降低太阳能采暖建筑的采暖运行费用,而且可降低整个系统的初投资。  相似文献   
97.
采用前置反硝化曝气生物滤池和聚氨酯填料进行高质量浓度生活污水的试验,控制进水在水力负荷0.64m3/(m2.h)、回流比1∶1的条件下,研究了不同气水比下的处理效果.结果表明,该装置处理效果好且稳定,当好氧段的气水比为20∶1时,去除效果最佳,具有明显的同步硝化反硝化特征,脱氮效果明显,去除率82.96%,出水质量浓度在10 mg/L以下.对好氧段沿层取样,结果表明总氮的去除主要发生在反应器底部0~0.6 m,表明此期间也就是溶解氧在1.5~2 mg/L下同步硝化反硝化作用明显,总氮去除率保持在80%以上.通过同时监测沿层氧化还原电位(oxidation-reduction potential,ORP)的变化,确定出ORP在同步硝化反硝化过程可给出控制信号且反应灵敏稳定.可根据ORP的变化情况,优化调节曝气量,以达到高效节能的效果.  相似文献   
98.
改善火炕炕面温度分布技术模拟   总被引:5,自引:0,他引:5  
为了使火炕的表面温度分布均匀,提高室内环境的热舒适性,提出了倾斜布置炕板来改善炕面温度分布的不均匀性.通过对炕板倾斜程度不同的落地炕和吊炕进行数值模拟,结果表明:当落地炕的炕头粘土层厚度为80 mm、炕梢粘土厚度为20 mm时具有相对最佳的取暖效果;当吊炕的炕头粘土层厚度为80 mm、炕梢粘土厚度为20 mm时具有相对最佳的取暖效果.  相似文献   
99.
In most multi-robot systems, an individual robot is not capable of solving computationally hard problems due to lack of high processing power. This paper introduces the novel concept of robotic clusters to empower these systems in their problem solving. A robotic cluster is a group of individual robots which are able to share their processing resources, therefore, the robots can solve difficult problems by using the processing units of other robots. The concept, requirements, characteristics and architecture of robotic clusters are explained and then the problem of “topological map merging” is considered as a case study to describe the details of the presented idea and to evaluate its functionality. Additionally, a new parallel algorithm for solving this problem is developed. The experimental results proved that the robotic clusters remarkably speedup computations in multi-robot systems. The proposed mechanism can be used in many other robotic applications and has the potential to increase the performance of multi-robot systems especially for solving problems that need high processing resources.  相似文献   
100.
北京奥运会已经结束,中国进入了"后奥运时代",奥运场馆的规划与设计以及赛后利用等问题引起了大众的再思考.对青岛奥帆中心的总体规划、建筑特色、赛后利用等方面进行分析,对青岛奥帆中心的赛前和赛后的规划设计进行比较总结.希望能够为以后的奥运建筑与大型体育场馆、体育建筑的建设和利用方面提供一些参考.  相似文献   
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