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91.
对文物标本进行系统分析归纳是传统工艺研究的必要途径,为实现越窑青瓷标本资料的资源共享,提高实验室工作效率,实现分析数据的科学管理,本研究开发设计了“浙江越窑青瓷标本信息数据库管理系统”.该系统基于B/S结构模式,以浙江省博物馆陶瓷标本中心的各类越窑瓷片标本来源、形态、化学成分、物理性能、显微结构、制作工艺等相关信息数据为基础,采用Wi ndows平台,以Visual Studi0 2010为开发环境,结合ASP.NET 4.0框架以及SQL Server数据库技术而构架.经过系统测试和实际运行证明,此管理系统具有良好的应用界面,交互性强,运行稳定,数据处理方便等优势,对实现古陶瓷研究信息资源共享,全面开展越窑青瓷的科学化研究提供了一个良好的数据平台.  相似文献   
92.
本文运用多种化学分析方法分析了浙江省田螺山遗址的地层土壤和地下水环境,得出了不同地层中主要元素的分布规律:再对古菱角外壳遗存和现代菱角外壳进行扫描电镜和元素分析,总结古菱角经长期埋藏后,外壳结构和化学元素的变化规律:最后初步探索古菱角类植物遗存的科技保护时策。  相似文献   
93.
This paper studies the relation between coalition structures in policy processes and policy change. While different factors such as policy images, learning processes, external events, or venue shopping are important to explain policy change, coalition structures within policy processes are often neglected. However, policy change happens as a result of negotiations and coordination among coalitions within policy processes. The paper analyzes how conflict, collaboration, and power relations among coalitions of actors influence policy change in an institutional context of a consensus democracy. Empirically, I rely on a Qualitative Comparative Analysis to conduct a cross‐sector comparison of the 11 most important policy processes in Switzerland between 2001 and 2006. Coalition structures with low conflict and strong collaboration among coalitions as well as structures with dominant coalitions and weak collaboration both facilitate major policy change. Competing coalitions that are separated by strong conflict but still collaborate strongly produce policy outputs that are close to the status quo.  相似文献   
94.
This article describes a simplified procedure for estimating the seismic sidesway collapse capacity of frame building structures incorporating linear viscous dampers. The proposed procedure is based on a robust database of seismic peak displacement responses of viscously damped nonlinear single-degree-of-freedom systems for various seismic intensities and uses nonlinear static (pushover) analysis without the need for nonlinear time history dynamic analysis. The proposed procedure is assessed by comparing its collapse capacity predictions on 272 different building models with those obtained from incremental dynamic analyses. A straightforward collapse capacity-based design procedure is also introduced for structures without extreme soft story irregularities.  相似文献   
95.
A new simplified procedure for estimation of floor response spectra (FRS) is proposed. This methodology enriches the most common procedures using nonlinear response-history analysis to predict FRS by including a direct multi-mode technique to estimate FRS. A novel feature of the procedure is that the coupling effect is considered to establish equivalent modal systems and the FRS are developed by incorporating capacity spectrum method in conjunction with ductility-based FRS for each modal system. Both the proposed method and the traditional method are applied to three steel moment frame structures, and a reasonable accuracy is demonstrated.  相似文献   
96.
    
This paper will present and discuss a multifaceted research project dealing with the production of cooking pots during the Iron Age II (ca. 1,000–586 BCE) Judah (modern Israel). In particular the new compositional analysis of 541 cooking vessels from 11 sites in Iron Age Judah will be presented. The study employs petrographic and chemical (NAA) analysis. The results of this ongoing research have already produced interesting information about production centers and movements of cooking pots in Iron Age II Judah. Apparently, the vast majority of the cooking pots sampled were made of a similar type of clay, related to terra rossa soil. This is true also for sites in the northern Negev and Judean Desert, where the type of soil was not available in the region of the sites. Furthermore, many of the cooking pots distributed around Judah were made in Jerusalem according to a well-located chemical profile (JleB). Other groups may represent Judean Shephelah production centers as the Lachish area as well as production centers in southern Israel or ancient Edom. The implications of the importation patterns of cooking pots by peripheral Judean sites will be discussed.  相似文献   
97.
ABSTRACT

Historical masonry structures are often located in earthquake-prone regions and the majority of them are considered to be seismically vulnerable and unsafe. Historical masonry towers are slender structures that exhibit unique architectural features and may present many inadequacies in terms of seismic performance. The seismic protection of such typologies of structures and the design of effective retrofitting interventions require a deep understanding of their behavior under horizontal loads. This paper presents the results of the seismic performance evaluation of historical masonry towers located in Northern Italy. A large set of case studies is considered, comprising a significant number of towers with high slenderness and marked inclination. First, a preliminary assessment of the dynamic behavior of the different towers is carried out through eigenfrequency analyses. Then, non-linear dynamic simulations are performed using a real accelerogram with different peak ground accelerations. A damage plasticity material model, exhibiting softening in both tension and compression, is adopted for masonry. The huge amount of results obtained from the non-linear dynamic simulations allows a comparative analysis of the towers to be performed in order to assess their seismic vulnerability and to show the dependence of their structural behavior on some geometrical characteristics, such as slenderness, inclination, and presence of openings and belfry. The evaluation of different response parameters and the examination of tensile damage distributions show the high vulnerability of historical masonry towers under horizontal loads, mainly in the presence of marked inclination and high slenderness. Some general trends of the seismic behavior of the towers are deduced as a function of the main typological features.  相似文献   
98.
The most common grass phytoliths from “Zambezian” miombos are described here for the first time. Their potential for long term preservation in sediments makes them a useful tool in the reconstruction of ancient plant communities and plant/human interactions. We processed 60 plant samples (26 identified genera and species), with an average of 300 phytoliths counted per sample to a total of 18,586. Forty-seven morphotypes were described as per the International Code for Phytolith Nomenclature, with exceptions, including forty-five discreet shapes and two articulated forms, which can be used as comparative reference materials. We conducted three forms of statistical analyses: Discriminant Analysis, Cluster Analysis, and Principal Component Analysis. The highest biomineral content was recorded among the Bambuseae and Paniceae, while the lowest silica production is detected in the Cynodonteae tribe. Typologically, the subfamily Panicoideae yielded 50% of the types reported here, 32% are from the Chloridoideae, 12% from the Bambusoideae, and 8% from the Arundinoideae sensu lato. Overall, the idealized Zambezian Poaceae phytolith spectrum is dominated by a small subset of Poaceae short cells, which include five morphotypes conventionally associated with Panicoid grasses (Bilobate concave outer margin long shaft, Bilobate concave outer margin short shaft, Bilobate convex outer margin long shaft, Bilobate convex outer margin short shaft, Cross), one morphotype commonly seen in Chloridoid taxa (saddle), and two types that appear across subfamily boundaries (tower, tower horned). The next logical step to take in regional phytolith research is the account of phytoliths deposited in soils underneath living plants, for they represent the interface between existing vegetation communities and the inevitably distorted fossil assemblages that the paleobotanist uses for environmental reconstruction.  相似文献   
99.
The 12th century Suntak chair is one of the earliest pieces of furniture known from Sweden. A close examination revealed minute remnants of possible colour pigments on several parts of the chair. Chemical analyses of the pigments revealed the presence of several colours such as black, white and red. This paper attempts to shed light upon the identification and origin of the pigments as well as the time of painting. The original use and the setting of the chair will also be discussed.  相似文献   
100.
对郑州商文化陶字符量化分析结果显示,早商文化陶字符使用以具有首都地位的郑州早商文化遗址最为集中,具有较强的地域性。郑州早商文化陶字符分期演进中出现一些分界现象,缘于商文化的兴盛和文化中心的转移。郑州商文化陶字符多出现于祭祀场所和手工业作坊遗址具有特殊意义的遗迹,表明其主要为生活、手工业生产、祭祀活动中有关数量、日期、位序、族属、地点等信息的记录遗存。  相似文献   
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