A user-programmable computational/control platform was developed at the University of Toronto that offers real-time hybrid simulation (RTHS) capabilities. The platform was verified previously using several linear ph...A user-programmable computational/control platform was developed at the University of Toronto that offers real-time hybrid simulation (RTHS) capabilities. The platform was verified previously using several linear physical substructures. The study presented in this paper is focused on further validating the RTHS platform using a nonlinear viscoelastic-plastic damper that has displacement, frequency and temperature-dependent properties. The validation study includes damper component characterization tests, as well as RTHS of a series of single-degree-of-freedom (SDOF) systems equipped with viscoelastic-plastic dampers that represent different structural designs. From the component characterization tests, it was found that for a wide range of excitation frequencies and friction slip loads, the tracking errors are comparable to the errors in RTHS of linear spring systems. The hybrid SDOF results are compared to an independently validated thermal- mechanical viscoelastic model to further validate the ability for the platform to test nonlinear systems. After the validation, as an application study, nonlinear SDOF hybrid tests were used to develop performance spectra to predict the response of structures equipped with damping systems that are more challenging to model analytically. The use of the experimental performance spectra is illustrated by comparing the predicted response to the hybrid test response of 2DOF systems equipped with viscoelastic-plastic dampers.展开更多
社交商务作为数字经济的重要组成,拥有巨大的市场潜力,但也面临着平台发展模式同质化等问题,导致形成固化用户的自我认识和网络信息行为的信息茧房。由于社交媒体的多样性、群体关系复杂性,茧房效应与社交商务结合的研究有待进一步挖掘...社交商务作为数字经济的重要组成,拥有巨大的市场潜力,但也面临着平台发展模式同质化等问题,导致形成固化用户的自我认识和网络信息行为的信息茧房。由于社交媒体的多样性、群体关系复杂性,茧房效应与社交商务结合的研究有待进一步挖掘。通过中国知网和Web of Science核心集,截至2023年3月31日,检索并筛选获取606篇相关文献,运用社会网络分析方法进行分析。其中300篇中文文献重点探讨个性化推荐算法对信息茧房形成的影响,306篇英文文献更多关注信息茧房与平台和用户行为之间的关系。基于信息茧房相关概念的研究明确其内涵和特征,根据平台、算法和用户3个维度的作用机制分析构建信息同质化视角下信息茧房形成机制框架,即社交平台内外部信息趋同导致了用户选择同质化、平台内容同质化以及用户群体同质化问题,并以正反馈的形式不断加强,最终形成信息茧房。由此,基于同质化视角,分别从政府、平台和用户3个主体层面提出社交商务平台应对信息茧房的策略。展开更多
基金NSERC Discovery under Grant 371627-2009 and NSERC RTI under Grant 374707-2009 EQPEQ programs
文摘A user-programmable computational/control platform was developed at the University of Toronto that offers real-time hybrid simulation (RTHS) capabilities. The platform was verified previously using several linear physical substructures. The study presented in this paper is focused on further validating the RTHS platform using a nonlinear viscoelastic-plastic damper that has displacement, frequency and temperature-dependent properties. The validation study includes damper component characterization tests, as well as RTHS of a series of single-degree-of-freedom (SDOF) systems equipped with viscoelastic-plastic dampers that represent different structural designs. From the component characterization tests, it was found that for a wide range of excitation frequencies and friction slip loads, the tracking errors are comparable to the errors in RTHS of linear spring systems. The hybrid SDOF results are compared to an independently validated thermal- mechanical viscoelastic model to further validate the ability for the platform to test nonlinear systems. After the validation, as an application study, nonlinear SDOF hybrid tests were used to develop performance spectra to predict the response of structures equipped with damping systems that are more challenging to model analytically. The use of the experimental performance spectra is illustrated by comparing the predicted response to the hybrid test response of 2DOF systems equipped with viscoelastic-plastic dampers.
文摘社交商务作为数字经济的重要组成,拥有巨大的市场潜力,但也面临着平台发展模式同质化等问题,导致形成固化用户的自我认识和网络信息行为的信息茧房。由于社交媒体的多样性、群体关系复杂性,茧房效应与社交商务结合的研究有待进一步挖掘。通过中国知网和Web of Science核心集,截至2023年3月31日,检索并筛选获取606篇相关文献,运用社会网络分析方法进行分析。其中300篇中文文献重点探讨个性化推荐算法对信息茧房形成的影响,306篇英文文献更多关注信息茧房与平台和用户行为之间的关系。基于信息茧房相关概念的研究明确其内涵和特征,根据平台、算法和用户3个维度的作用机制分析构建信息同质化视角下信息茧房形成机制框架,即社交平台内外部信息趋同导致了用户选择同质化、平台内容同质化以及用户群体同质化问题,并以正反馈的形式不断加强,最终形成信息茧房。由此,基于同质化视角,分别从政府、平台和用户3个主体层面提出社交商务平台应对信息茧房的策略。