A High-Performance Quadrilateral Flat Shell Element for Seismic Collapse Simulation of Tall Buildings and Its Implementation in OpenSees

Shear walls are important lateral force-resistant components of tall buildings. Hence, a reliable numerical model that can accurately represent the mechanical characteristics and large deformations of shear walls is critical for realistic collapse simulation of tall buildings. Based on the theory of generalized conforming element, a high-performance quadrilateral flat shell element, NLDKGQ, accounting for the large deformation using the updated Lagrangian formulation, is proposed herein and implemented in OpenSees. The reliability of NLDKGQ is validated using classical benchmark problems and reinforced concrete specimens. In addition, its capability in simulating the collapse of a tall building is also demonstrated.     

Modelling and Seismic Response Analysis of Italian Code-Conforming Base-Isolated Buildings

ABSTRACT

This paper reports on results of nonlinear analyses performed within the RINTC project on an RC building isolated with different systems (High Damping Rubber Bearings, High Damping Rubber Bearings and Flat Sliding Bearings, Friction Pendulum System) and designed according to the Italian design code. The seismic response has been evaluated under different seismic input levels of two sites with different hazard and by considering two Limit States: Global Collapse and Usability-Preventing Damage. The influence of seismic stoppers and modelling uncertainties is also evaluated. Results permit to compute the implicit collapse risk and to identify critical aspects of current design procedures.     

The impacts of parental migration on children’s subjective well-being in rural china: a double-edged sword

ABSTRACT

The emerging problem of left-behind children has attracted mounting academic and policy attention. Prior studies primarily cast light on left-behind children’s education, health, and behavior, while their subjective well-being is much less understood yet. Based on a nationally representative sample of rural children aged 10–15 in 2014, we examine the impacts of different types of parental migration on children’s subjective well-being and how these affects vary between boys and girls. The results show that parental migration is a double-edged sword: children from both-parent migrant families report compromised life satisfaction and relationship quality compared with those in integral families, and mother-only migration significantly lowers children’s subjective health. On the flip side, father-only migration enhances children’s aspiration for attaining college, an encouraging effect that is even stronger than that of parental education and family income. These effects are heterogeneous by children’s gender: boys seem to be more susceptible to the disruptive effects of both-parent migration; mother-only migration effectively promotes girls’ educational aspiration while father-only migration promotes boys’. This study portrays a comprehensive image of left-behind children. Relaxation of hukou restriction, equal access to education, and revitalization of rural economies are imperative to improve the well-being of left-behind children.

Abbreviations: LBC: Left-behing children; SWB: subjective well-being     

Timber economy in the Roman Age: charcoal data from the key site of Herculaneum (Naples,Italy)

The city of Herculaneum (Naples, southern Italy), buried by the volcanic eruption of Mount Somma-Vesuvius in 79 ad, is a key site for understanding the timber economy during the Roman period. In this paper, the results of charcoal analysis of different building element types are presented. Beams, joists, poles, planks and door and window frames were investigated allowing us a view of which timber the Romans preferred for building in this area. We also fit the taxonomic results into the reconstruction of the ancient Campanian landscape, and finally, we discuss the knowledge that the Romans had about the technological properties of the wood that they used for building and the possible selection criteria that they followed in choosing them. Coniferous timber is the preferred material for building purposes. Abies alba is especially used, this fact confirming its stronger presence in southern Italian woods during the past and suggesting that its decline is mainly due to human overexploitation. The large presence of Cupressus sempervirens, selectively used for the production of poles, confirms that this tree was cultivated in plantations for timber production in the Vesuvius area. Furthermore, it might indicate that cypress could have been present as a natural tree in the local vegetation, suggesting a forest type that nowadays almost completely disappeared from this area and from the entire Italy. The findings of Juglans regia, Pinus pinea and Olea europaea, typical elements of the Mediterranean cultural landscape, show that their use was not limited to fruit production and that Romans also appreciated their timber. Beside these local resources, the presence of Picea abies and Picea/Larix indicates the importation of timber from northerly regions, probably the northern Apennines and the Alps.     

博物馆影响力刍议

博物馆影响力的程度制约着博物馆社会价值实现充分与否,因而博物馆影响力问题处于博物馆理论体系的核心位置。博物馆影响力的产生基于博物馆物质资源、无形资源与现代媒介的应用;其特点体现为复杂性、非权力性与缓释性;其影响涉及公众、社会与同行业三个层面。而对博物馆影响力理论研究的最终目的在于寻求提升之路径。     

Decolonizing travesti space in Buenos Aires: race,sexuality, and sideways relationality

Scholars of space usually neglect the history of travesti populations in Latin America. It is misrepresented not only by disciplinary blind spots but also by global narratives concerned with rehabilitating queer subjects within homonormative projects. Analyzing neoliberal narratives that delink conflicts about racialization and sexuality in Argentina, this article makes room to decolonize the study of travesti experience and embodiment in Buenos Aires's red zone. It examines a network of racialized travestis and their spatial practices, including their migration from the Andean northwest to the sex-work circuits of Buenos Aires. Finally, this article introduces the notion of sideways relationality to account for the cultural and spatial labor that racialized travestis perform at the oppositional margins of homonormative reflexivity.     

萧何收集整理图书文献之功探微

文献是伴随着文化的创造而产生的。汉代的图书收集与整理主要是由汉武帝倡导,刘向、刘歆父子集大成,但不能忽视开国元勋萧何的奠基之功。文章从保护与利用、收集与创建等方面揭示了萧何对文献学及整个中华文化史作出的贡献。     

河南北宋壁画墓的题材及艺术特色

北宋墓室壁画是宋代绘画的重要组成部分,题材有日常生活、孝行故事、超度升仙和装饰性画面等四类,布局、构图都遵循一定的程式,但构思巧妙、技法多变,体现了北宋绘画艺术的丰富多彩与繁荣昌盛。     

青海省阶梯式旅游模式的探讨

一、问题的提出青藏高原是地球上隆起最高、最年轻的高原,平均海拔4000米以上,有“世界屋脊”和“地球之巅”之称。长期以来,青藏高原以其年轻的地质发展史、活跃的新构造运动、剧烈的环境演变、独特的生物多样性、丰富多彩的自然景观,以及由此孕育的独特的各民族     

Sino–American relations: new changes and new challenges

Sino–American relations encompass a highly complex array of cooperative and competitive dimensions. Recently, they have evolved around the question of ‘China's rise’ or (as Chinese analysts would state it) ‘peaceful evolution’. This article surveys both the cooperative and competitive structural elements of this important bilateral relationship. It tracks recent transitions in that relationship, arguing that China's new-found status as a ‘responsible stakeholder’ in American eyes will present a new set of American expectations and new forms of strategic collaboration that will seriously test both sides’ policy creativity and ability to adapt to a rapidly changing global environment.