Modification of Ductility Reduction Factor for Strength Eccentric Structures Subjected to Pulse-Like Ground Motions

This article investigates the ductility reduction factors for RC eccentric frame structures subjected to pulse-like ground motions. The structural models are with the strength eccentricities which are much disadvantageous than the stiffness eccentricities during the inelastic response range. A method to determine the ductility reduction factors of the strength eccentric structures is suggested by modifying those of reference symmetric structures through an eccentricity modification factor. The four factors of strength eccentricity ratio, ductility ratio, story number and velocity pulse of ground motions, are investigated to gain insight into this modification factor. It shows that the ductility reduction factors of the eccentric structures are clearly smaller than those of the symmetric structures. The eccentricity modification factor is mainly affected by the strength eccentricity and the ductility ratio, decreasing with the increment of the eccentricity or the decrement of the ductility ratio in a medium eccentricity range. The earthquake pulse-like effect and the eccentricity have coupling influence on the modification factor, while the effect of story number is not apparent. Based on the results of a comprehensive statistical study a simplified expression is suggested, which can estimate the eccentricity modification factors for both pulse-like and nonpulse-like ground motion cases.     

制度约束与德性激励——建构公共行政伦理的两重维度

公共行政伦理的建构是基于人性假设的,解读公共行政领域的伦理困境必须分析公共行政人员人性中“经济人”与“公共人”的双重特性。由此,可以引伸出建构公共行政伦理的两重维度:制度约束与德性激励。制度约束是基于“经济人”假设的伦理规制,是防止人性的向下堕落,是抑“恶”;德性激励是对“公共人”假设的理性张扬,是实现人性的向上提升,是扬“善”。     

北京城市老年人社区满意度研究——基于模糊评价法的分析

本文基于对北京市三个典型城市社区中老年人社区满意度的问卷调查,运用模糊评价法,对老年人的社区满意度进行案例研究。结果发现,老年人对社区社会环境较为满意,而对社区服务设施等社区物质环境不满;老年人更关注住房条件,而对社交和人际关系的关注较少。老年人特别重视的因子满意度不高,可能是导致社区满意度的综合模糊结果偏低的原因。进一步通过相关性分析和交叉表分析,从个人属性、家庭结构和所在社区类型等三个层面探讨社区满意度评价的影响因素,发现年龄低、学历高、收入高、与孙辈同住的老年人以及旧城平房社区中老年人社区满意度较高。老年人的社区满意度,将成为测度城市老年人生活品质的重要指标。     

Compositional and Microstructural Study of KoryŎ Celadon and Whiteware Excavated from SŎRi Kiln in Kyŏnggi Province

An extensive study of the composition and microstructure of celadon and whiteware sherds excavated at Sori, one of the most important sites that were active during the founding stage of the stoneware and porcelain industry in Korea, was carried out. The analysed sherds were organized according to four different levels of the excavation and four different styles of haemurigup foot rim. Principal component analysis of the chemical compositions of the sherds revealed slight differences in their body and glaze compositions between the levels of excavation. Porcelain stone with high silica and low aluminium contents was generally used as the body material and wood ash as the chief flux in the glaze. Over the period of operation, the aluminium content in the bodies of the ceramics decreased and the P₂O₅ content in the glazes increased. Glazed bodies were fired in a single step, in contrast to the two‐step method used in later ceramic production. Firing conditions were adjusted to produce vitrification of the glazes, which meant that vitrification of the ceramic bodies occurred to varying extents, mostly determined by the relative contents of flux in the body and the glaze.     

酋邦的演化

在文明与早期国家探源的战略性课题中,酋邦理论具有十分重要的意义。酋邦作为对19世纪摩尔根社会进化理论的发展和20世纪新进化论的重要概念,赋予了平等的部落社会与作为阶级社会象征的国家之间这个过渡阶段以明确的科学定义,使这方面的探索有了一个有用的分析工具。至于这个概念的具体内涵和分析视野,则是始终处于发展之中的。酋邦概念最早是20世纪50年代奥博格在对南美印第安人的研究中提出的,60年代塞维斯根据夏威夷群岛原始文化的资料提出了相对比较系统的酋邦理论。此后酋邦问题引起学术界越来越多的重视和关注,很多学者参与到这方面的研究和讨论之中,使研究深度和广度都达到了很高的水平。本文是美洲研究学会1988年1月举行的一个酋邦研讨会的纪要,曾发表在1989年2月号的《当代人类学》(Current Anthropology)上,稍作修改后又收入厄尔主编的《酋邦:权力、经济和意识形态》(Chiefdoms:Power,Economy,andIdeology)(1991年出版)一书中。这个研讨会是该领域一流学者们的一次集会,对酋邦问题进行了非常深入全面的探讨。会上所提出的一些问题,不仅仅是对当时酋邦研究成果的一次总结,而且对于后来包括今天在内的国家文明起源研究都有十分重要的意义。会议不仅探讨了酋邦的概念,更着重探讨了酋邦产生和存在的动力机制。首先,酋邦被认为具有极大的多样性。从规模上可分为简单酋邦和复杂酋邦;从财政基础而言,根据支付媒介的特点,可以区分为产品经济型酋邦和财富经济型酋邦;从结构上,酋邦可以分为集体型酋邦和个体型酋邦。其次,伴随对当时盛行的人口压力是社会演变主要原因学说的反思,学者们全面探讨了酋邦权力起源可能存在的所有动力,主要从三个方面(对经济、战争和意识形态的控制)总结为十项策略。与会者的一种共识是,权力的三个组成部分某种程度体现了不同的策略,而有效的统治似乎有赖于多种不同策略结合使用,以便集中权力并克服单一权力来源的局限性,这是各地案例中较为普遍的现象。另外,会议还讨论了环境在酋邦发展中的作用、酋邦的规模与层次、以及酋邦的轮回等等其它一些重要问题。酋邦概念在1980年代引入中国后也引起了我国学界的关注和讨论,然而由于对国外文献理解上的不足,一些介绍酋邦的文章难免传递一些误导性的观点。本文作为酋邦专题讨论的纪要或综述,体现了当今国际学界对酋邦概念的认识和研究,为我们了解酋邦探究的意义提供一个比较准确和全面的认识。     

抗战后的南京救火会

南京救火会为民国时期的南京民间消防队,在抗战结束后,得到迅速恢复。由于火灾危害较大,各地热心人士出于自身安全考虑,对南京救火会给予较大的支持。同时,南京作为中华民国的首都,首都警察厅对于民办救火组织也加强了管理,使南京救火会在保障本市消防安全方面发挥了巨大作用。     

p‐Functional Clusters Location Problem for Detecting Spatial Clusters with Covering Approach

Regionalization or districting problems commonly require each individual spatial unit to participate exclusively in a single region or district. Although this assumption is appropriate for some regionalization problems, it is less realistic for delineating functional clusters, such as metropolitan areas and trade areas where a region does not necessarily have exclusive coverage with other regions. This paper develops a spatial optimization model for detecting functional spatial clusters, named the p‐functional clusters location problem (p‐FCLP), which has been developed based on the Covering Location Problem. By relaxing the complete and exhaustive assignment requirement, a functional cluster is delineated with the selective spatial units that have substantial spatial interaction. This model is demonstrated with applications for a functional regionalization problem using three journey‐to‐work flow datasets: (1) among the 46 counties in South Carolina, (2) the counties in the East North Central division of the US Census, and (3) all counties in the US. The computational efficiency of p‐FCLP is compared with other regionalization problems. The computational results show that detecting functional spatial clusters with contiguity constraints effectively solves problems with optimality in a mixed integer programming (MIP) approach, suggesting the ability to solve large instance applications of regionalization problems.     

民国钢筋混凝土建筑遗产的结构构造设计方法研究

民国钢筋混凝土建筑的结构构造设计方法研究可为民国钢筋混凝土建筑的结构安全评估及加固修缮提供依据。从材料到构件层面,通过对民国时期历史资料的研究,得出民国钢筋混凝土结构的构造设计方法,结合测试数据的分析,与现代钢筋混凝土建筑的结构构造设计方法进行对比研究。结果表明:民国混凝土建筑的混凝土立方体抗压强度检测数据的平均值为16.36MPa,与民国时期的设计要求总体基本吻合;民国混凝土建筑的方钢极限抗拉强度检测数据的平均值为375.86MPa,小于民国时期的设计要求;而圆钢极限抗拉强度检测数据的平均值为464.37MPa,大干民国时期的设计要求。民国时期的混凝土梁钢筋保护层厚度、梁下部纵筋间距、承受均布荷载梁的跨高比、梁下部受弯钢筋截断位置、梁箍筋直径基本满足现行混凝土结构设计规范的要求;而梁上部纵筋间距、承受集中荷载梁的跨高比、梁纵筋的搭接长度、梁上部受弯钢筋截断位置、梁箍筋布置和间距不满足现行混凝土结构设计规范的要求。民国时期的混凝土柱钢筋保护层厚度、柱纵筋间距、柱纵筋配筋率、柱箍筋直径、柱箍筋布置和间距基本满足现行混凝土结构设计规范要求;而柱纵筋的搭接长度和搭接位置不满足现行混凝土结构设计规范要求。民国时期的混凝土板厚度、板筋间距、板分布筋布置方式基本满足现行混凝土结构设计规范要求;而板的钢筋保护层厚度不满足现行混凝土结构设计规范要求。