An Investigation of the Ground Motion Scaling Procedures for the Nonlinear Seismic Analyses of Concrete Gravity Dams

Seismic assessment of gravity dams is generally carried out using time history analyses. Scaling of the motions is commonly used; however, in contrast to buildings, the performance of scaling procedures at predicting the mean and reducing the dispersion in engineering demand parameters (EDPs) is not known. The main goal of this study is to assess the performance of different scaling procedures in predicting seismic demands on dams. The performance regarding the prediction of the damage and the required number of motions for effective analysis was investigated. The results show that techniques commonly used for moment frames should not readily be applied to these structures.     

Bayesian Parameter Identification and Model Selection for Normalized Modulus Reduction Curves of Soils

This work develops a procedure that involves the use of Bayesian approach to quantify data scatterness, estimates the optimal values of model parameters, and selects the most appropriate model for the construction of normalized modulus reduction curves of soils. The proposed procedure is then demonstrated using real observation data based on a set of comprehensive resonant column tests on coarse-grained soils conducted in the study.     

Effects of Different Record Selection Methods on the Transverse Seismic Response of a Bridge in South Western British Columbia

The seismic response of a continuous 4-span bridge designed according to the current Canadian seismic provisions is investigated using Incremental Dynamic Analysis (IDA). Different earthquake types, including shallow crustal events, interface Cascadia subduction, and deep inslab subduction are considered. The median collapse capacities calculated using different record selection methods including Conditional Mean Spectrum (CMS)-based, Uniform Hazard Spectrum (UHS)-based, and epsilon-based methods are compared. The use of the epsilon-based method generally resulted in the highest collapse capacity predictions, but the CMS-based method was less sensitive to the number of records considered in the IDA.     

孙殿起《贩书偶记》的史料价值

从表面上看,《贩书偶记》只是书商出身的文献家孙殿起先生在经营古书时编录的一部图书目录,但它在著录图书之时,对与各图书相关的重要信息或多或少地作了一些抄录,这些信息包括撰者的生平传记、著述情况、书籍本身的刊刻、序跋等等,尽管零零总总,却有着十分重要的史料价值。     

A Method for Selecting Ground Motions that Considers Target Response Spectrum Mean and Variance as Well as Correlation Structure

This study proposes a method for selecting ground motions from a ground motion library with response spectra that match the target response spectrum mean, variance, and correlation structures. The proposed method is conceptually simple and straightforward. In this method, a desired number of ground motions are sequentially selected from first to last. The accuracy and consistency of the proposed method are verified through comparisons of the ground motions selected using the proposed method with those selected using conventional methods. This study shows that the seismic responses of the frames vary according to ground motion selection and correlation structures.     

从文学视角看《零售商菲化案》对华侨社会的影响——以《二十世纪五十年代商报小说选》为主的分析

论文通过对《二十世纪五十年代商报小说选》作品的分析,介绍了《零售商菲化案》产生的背景和主要内容;展示了《零售商菲化案》对菲律宾华侨零售商的冲击和在此背景下菲律宾华侨的悲惨命运,并对这段历史进行了客观理性的分析评价。一方面,菲律宾独立建国以后,为了发展经济,建设国家,必然要通过各种手段整合社会力量与有关资源。遗憾的是,菲律宾政府在经济危机面前,舍本求末,把危机转嫁在华侨身上,造成了20世纪50年代菲华社会的惶惑与动荡;另一方面,菲律宾华侨也必须经过一个转型期,才能更好地在当地生存发展。或许说,正是因为有了20世纪50年代的惶惑与动荡,才加速了菲华社会与当地社会的融合。     

修昔底德选用史料方法刍议

修昔底德的史著以叙述伯罗奔尼撒战争为主要内容,涉及希腊世界主要城邦的政治、军事、经济、外交以及海陆交通等方面丰富多样的史料。修昔底德按照自己处理史料的原则,对于战前史和战争史本身的史料分别采取了不同的处理方法。对于战前史料的选择和考信方法主要采用比较考异法和反溯法;对于当代史料的选用及考信方法主要采取实录法、辨异法、推测法、纠错法、隐微法等五种。修昔底德貌似如实直书的表象背后,隐含着名副其实的“修昔底德陷阱”。     

乾卦六龙态的天文含义研究--《左传》"龙纪"历法钩沉

《左传》昭公四年的“龙纪”,是上古以苍龙星为历象的太阳历的记载。这个苍龙星星象在《易经》乾卦六爻爻辞中有形象的描述,根据寅月“见龙”、午月“跃龙”等记载,可知其观测年代当在夏代以前。这种借龙“以喻天之阳气”的龙纪历法流传至先秦秦汉,或称“易历”、“气历”;或称“律历”、“甲历”。它以天干记日,十日为旬,六旬为甲,六甲为岁,一岁360日;并通过不记在日序之内的56日的过年日使历年长度略等于回归年长度,从而形成了原始社会晚期一部较实用的历法。     

Variable Selection in Artefact Compositional Studies

In artefact compositional studies, the selection of variables to use in analysis is unavoidable. Given this ubiquity, surprisingly little attention has been paid to ways in which variables might be selected. After arguing the case for the importance of variable selection, two systematic approaches to making a choice, which have had little or no application in archaeometry, are discussed and illustrated. One, based on the use of principal components, is appropriate if structure in the data is not known. The other, based on the use of classification trees, is applicable when there are known or assumed groups in the data.     

Anarchy in Our Churches? The American Architectural Press, 1944–65

In the mid-twentieth century American architectural journals, including Architectural Forum, Architectural Record, and Progressive Architecture, routinely ran features on the state of contemporary church architecture in the United States. Rapid suburban expansion and the revival of religious life in the post-Depression, postwar era generated tremendous amounts of construction, with a great deal of work available for architects. This article examines the concerns and hopes of modernist editors in the 1940s–1960s, as they sought to stabilize a “direction” for church architecture. Specifically, it examines the role of the architectural press as the self-established gatekeepers for acceptable church design, and their relationship with theologians, liturgists, and building commissions within the Catholic Church. Questions of authority (who was competent to determine whether a church design was successful?) and expertise (whose theological knowledge should be weighted more heavily?) lay behind the stark assertions commonplace in these discussions. Editors, generally not themselves Catholic, used their professional positions to weigh in on hot debates within the Catholic Church over the purpose of a church building, the relationship of the Church to modernity (and modernism), and the appropriateness of new materials and engineering techniques.