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31.
于群力  阎敏  杨秋颖 《文博》2009,(6):280-284
为了科学保护山西省崇庆寺宋、明时期的彩塑文物,作者深入调查了该寺彩塑的现状与病害,分析检测了泥塑土的配比、成分与彩绘颜料,并对比分析了该寺不同时期彩塑的材质及工艺特点。结果表明,宋代彩塑的病害类型、严重程度等较其它时期的彩塑明显要少和轻。这一现象启示我们探讨这批彩塑的造型设计、制作技艺、材料选择等具有重要的现实意义。  相似文献   
32.
This study addresses buff-firing clay sources in dynamic alluvial settings along Arizona’s Gila River in the U.S. Southwest. We establish clay resource distribution relative to the geomorphic histories of the Lower and Middle Gila River based on 38 clay samples and ethnographic data from two US Bureau of Reclamation (BOR) projects. Buff-firing clayey alluvium, deposited in the Gila River floodplain 800 to 1,500 or more years ago, was a surficial ceramic raw material source for prehistoric Hohokam and lowland Patayan potters. This geomorphic unit was later removed in some places and buried by up to 3-4 m of sediment in others, reducing the availability of buff-firing clays in the Hohokam Classic period and requiring historic Pee Posh and Akimel O’odham potters to dig pits to access it. Sources were further destroyed in catastrophic floods in the late 19th and early 20th century, affecting ceramic manufacture patterns and ultimately contributing to the decline of pottery production by the O’odham living in the Gila River Valley. Our results contribute to regional ceramic ecology and should also be of interest to others investigating alluvial clay use in general or buff-firing alluvial clays in particular. The study also illustrates the value of combining geomorphic and ethnographic data to examine major changes in resource distribution and use.  相似文献   
33.
杨启楚 《神州》2011,(4X):7-9,12
特殊教育是对残疾人的一种教育,是社会的人本、民主、公平的反映,是国家及其文明程度的一个窗口。通过对浙江省金华市七所特殊教育学校现状的调查与研究,了解到近几年金华市的特殊教育有很大的发展,但是在办学规模、地理位置、师资力量、硬件设施等方面还存在不足,影响了学龄残疾儿童的入学率与特殊教育的发展速度。故立足于金华市特教的现实问题,提出具有可行性的方法与对策,促进金华市特殊教育事业更好更快的发展。  相似文献   
34.
This research examines the evidence for prehistoric ceramic exchange networks over the last 2000 years in northwest Alaska through the use of neutron activation analysis of ceramic artifacts. Results from ceramic analysis on eight coastal and inland archaeological sites identified three source macrogroups and three associated subgroups. Clay source diversity and shared source macrogroups between geographically distant sites suggest the use of multiple sources and/or the movement of pots between production locales, mirroring related patterns in pottery stylistic data. Although additional analytical work is needed to fully understand the changing character of clay procurement and ceramic distribution across this time period, this study provides exploratory data on past ceramic production and distribution that hints at changes in exchange and territoriality in northwest Alaska during the late Holocene.  相似文献   
35.
随着"秦始皇帝陵博物院·丽山园"正式对外开放,管理者面临着多重的管理压力,为此以秦始皇帝陵文化遗产地的实际出发,将影响文化遗产管理的安全因素从地理尺度上划分为的遗产地尺度、遗址尺度和文物尺度,着重以这三个尺度为出发点分析了安全监控、遗址风貌、气候环境、人为活动等影响因素,并就如何更好地开展大遗址的文化价值传播提出了自己的见解。  相似文献   
36.
In this article, an explicit integration scheme for dynamic finite element analysis is developed and the formulations for linear elastic solid and two-phase porous media are derived. The accuracy and stability characteristics analyses show this scheme is second-order accurate, which is the same as the Central Difference Method (CDM), and possesses a broader scope of stability within the range of normal damping ratios of media. Comparing with the CDM, this explicit scheme requires no matrix factorization even if a non diagonal damping matrix is included. Therefore, the dynamic finite element equations can be integrated economically provided that the mass matrix is diagonal. To demonstrate the validity of the present scheme, three examples are provided. First, taking a single-degree-of-freedom system as an example, the results obtained by the proposed scheme are compared with the exact solutions. Second, the dynamic responses of half-space saturated porous media, subjected to a concentrated load pulse at the surface, are analyzed. Both examples show that the results obtained by the proposed scheme agree well with the analytical solutions. Finally, the dynamic responses of a plane strain plate due to a load pulse are analyzed, respectively, by the proposed procedure and the commercial code ABAQUS (both implicit module and explicit module), and the CPU costs are compared.  相似文献   
37.
Ground-supported steel tanks experienced extensive damage in past earthquakes. The failure of tanks in earthquakes may cause severe environmental damage and economic losses. This study deals with the evaluation of the elastic buckling of above-ground steel tanks anchored to the foundation due to seismic shaking. The proposed nonlinear static procedure is based on the capacity spectrum method (CSM) utilized for the seismic evaluation of buildings. Different from the standard CSM, the results are not the base shear and the maximum displacement of a characteristic point of the structure but the minimum value of the horizontal peak ground acceleration (PGA) that produces buckling in the tank shell. Three detailed finite element models of tank-liquid systems with height to diameter ratios H/D of 0.40, 0.63, and 0.95 are used to verify the methodology. The 1997 UBC design spectrum and response spectra of records of the 1986 El Salvador and 1966 Parkfield earthquakes are used as seismic demand. The estimates of the PGA for the occurrence of first elastic buckling obtained with the proposed nonlinear static procedure were quite accurate compared with those calculated with more elaborate dynamic buckling studies. For all the cases considered, the proposed methodology yielded slightly smaller values of the critical PGA for the first elastic buckling compared to the dynamic buckling results.  相似文献   
38.
This article proposes a damage index for the seismic analysis of Reinforced Concrete members using the hysteretic energy dissipated by a structural member and a drift ratio related to failure in the structure. The index was calibrated against observed damage in laboratory tests of 76 RC column units under various protocols. Values obtained in this calibration had acceptable agreement with the levels of damage observed in the test specimens. An analysis of the parameters involved in the definition of the proposed damage index shows the importance of displacement history in the drift ratio capacity of structures.  相似文献   
39.
The first step in a hysteretic energy-based design approach of performance-based design is the estimation of hysteretic energy demand in the structure. A nonlinear response-history analysis of the multi-degree of freedom model gives an accurate estimation, but it is not suitable for adopting in design. Two alternative methods, based on the concepts of modal pushover analysis (MPA) and 2D-MPA, are proposed in this article for uniaxial plan-asymmetric structures. Application studies show that both methods are efficient. While the 2D-MPA-based method is more accurate, the MPA-based method is more suitable for design adoption. Significant conclusions are given for prospective application of these methods.  相似文献   
40.
This study develops seismic fragility curves for vertical-pile-supported wharves commonly found in the western United States. Nonlinear time-history analyses of a two-dimensional numerical model under two ground motion suites are performed. The results show that the jumbo container cranes increase by 10.8% in the wharf deck drift. By using the experiment-based limit states, the proposed fragility curves demonstrate that, at a PGA of 0.50 g, the probabilities of exceeding slight, moderate, extensive, and complete limit states are approximately 23.0%, 7.0%, 4.0%, and 3.0%, respectively, while at a PGA of 1.00 g, the exceeding probabilities increase to 44.0%, 19.0%, 14.0%, and 11.0%, respectively.  相似文献   
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