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51.
网上购物系统的工程心理学设计因素 总被引:4,自引:0,他引:4
在影响网上购物发展的诸多因素当中,网上商店的信息结构、界面与交互方式等工程心理学因素一直是容易被人忽视而又是十分重要的因素,它是造成购物者不满意购物经验的重要因素,因为购物者要在网上商店里众多而纷杂的商品信息中寻找所要求的信息不太容易,从而难以实现网上购物,并产生较大的负面效果。并且实际应用中也缺乏必要的对网上购物系统相关工程心理学因素的系统分析与理解。本文依据工程心理学的主要原理,从用户特征、购物任务、信息环境三个方面分析可能对网上商店设计产生重要影响的主要因素,以期增进对网上购物的交互与设计的理解。 相似文献
52.
本文就土石坝应用土工膜进行坝体防渗,对其透水性及渗漏量、土工膜防渗层与坝体间的作用、土工膜厚度的计算方法作了介绍,可供土石坝应用土工膜防渗设计参考。 相似文献
53.
具有柔性铰链的差式微位移放大机构 总被引:15,自引:1,他引:15
阐述了差式微位移放大机构的基本设计原理,分析了机构中位移损失的原因。研制的放大机构具有较好的放大效果,而且机构的位移输出线性特性也较好。采用片状柔性铰链成功地解决了由于机构中的位移干涉造成的机构内部反力太大的问题。 相似文献
54.
This research project explores to what extent the utilization of open-source 3D printers and 3D design software could serve as means of learning and communication. The principles of non-formal education aligned with the concept of constructionism are used to create an experimental educational scenario focused on geocultural tourism for persons with visual impairments. This paper documents our experience and presents our findings from a 25-day long project, which took place in Zagori, northwestern Greece. 11 high school students from Portugal designed and manufactured natural and cultural heritage artifacts carrying messages in the Braille language. The objects were then handed to people with visual impairments with a twofold aim. First, to enable the communication among persons with and without visual impairments; and, second, to empower students to participate in training projects through open educational procedures. We conclude that open educational practices can boost students’ active engagement in educational processes. Finally, 3D printing encourages a meaningful communication among people with and without visual impairments via the tangible exploration of geocultural components. 相似文献
55.
Detecting and understanding human action under sophisticated lighting condition and backgrounds, also known as human action recognition in real-world context, is an indispensable component in modern intelligent systems and has becoming a hot research topic currently. Nowadays, human action recognition is still a tough challenge due to intra-class and inter-class, environment and temporal-level differences of the same action. Algorithms based on the single visual channel cannot achieve satisfactory performance. Thus, in this paper, we propose a novel action recognition framework towards sophisticated activity understanding, focusing on intelligently combining multimodel quality-related action features. Specifically, we first design a multi-channel feature fusion (MCFF) algorithm to capture visual appearance, motion and acoustic patterns from each video frame, where image-level labels are characterized by choosing high quality multimodel features. Subsequently, we design an adaptive key frame selection algorithm that can be applied to characterize human action from human action video stream. Thereafter, we engineer a multimodel feature based on an auxiliary human action retrieval system to achieve sophisticated activity understanding. Extensive experimental evaluations have demonstrated that the effectiveness and robustness of our proposed method. 相似文献
56.
Roberto Sastre Virginia Martín Leoncio Garrido José Luis Chiara Beatriz Trastoy Olga García Angel Costela Inmaculada García‐Moreno 《Advanced functional materials》2009,19(20):3307-3316
Here, the design, synthesis, and characterization of laser nanomaterials based on dye‐doped methyl methacrylate (MMA) crosslinked with octa(propyl‐methacrylate) polyhedral oligomeric silsesquioxane (8MMAPOSS) is reported in relation to their composition and structure. The influence of the silicon content on the laser action of the dye pyrromethene 567 (PM567) is analyzed in a systematic way by increasing the weight proportion of POSS from 1 to 50%. The influence of the inorganic network structure is studied by replacing the 8MMAPOSS comonomer by both the monofunctionalized heptaisobutyl‐methacryl‐POSS (1MMAPOSS), which defines the nanostructured linear network with the POSS cages appearing as pendant groups of the polymeric chains, and also by a new 8‐hydrogenated POSS incorporated as additive to the polymeric matrices. The new materials exhibit enhanced thermal, optical, and mechanical properties with respect to the pure organic polymers. The organization of the molecular units in these nanomaterials is studied through a structural analysis by solid‐state NMR. The domain size of the dispersed phase assures a homogeneous distribution of POSS into the polymer, thus, a continuous phase corresponding to the organic matrix incorporates these nanometer‐sized POSS crosslinkers at a molecular level, in agreement with the transparency of the samples. The silicon–oxygen core framework has to be covalently bonded into the polymer backbone instead of being a simple additive and both the silica content and crosslinked degree exhibit a critical influence on the laser action. 相似文献
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母线是电力供应系统供应中的主体部分,在电力输送系统中发挥着重要作用,本文对母线继电保护动作行为仿真分析系统的研究主要从系统基本设计原理入手,实现我国电力系统科学发展. 相似文献
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