首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   45篇
  免费   5篇
  2024年   2篇
  2023年   4篇
  2021年   1篇
  2019年   4篇
  2018年   5篇
  2017年   2篇
  2016年   5篇
  2015年   4篇
  2014年   1篇
  2013年   3篇
  2012年   4篇
  2011年   2篇
  2010年   1篇
  2009年   2篇
  2008年   1篇
  2007年   1篇
  2006年   2篇
  2005年   2篇
  2004年   2篇
  2001年   1篇
  1983年   1篇
排序方式: 共有50条查询结果,搜索用时 343 毫秒
1.
ABSTRACT

The “Quartel das Esquadras” is an 18th century infantry barrack located within the limits of the bulwarked fortress of Almeida, in Portugal. An ongoing adaptive reuse project of the building aims to recover its full capacity and also its importance, by implementing a variety of new uses. The architectural intervention results in the need of the structure to withstand new and diverse imposed loads. As the current configuration of the structure will be altered, the main objective of this article is to evaluate the suitability of some of the proposed structural interventions. The current condition has been characterized following a multidisciplinary approach comprising historical research, visual inspection, non-destructive testing, and structural analysis to identify the possible sources of major structural problems. A portion of the building particularly affected by the alterations has been selected to carry out structural analysis. A comparative safety assessment of the selected area in both current and altered condition has been done through finite element modelling and nonlinear static analysis, resulting in an identification of the weaker points against the new implemented loads and alterations. Finally, proposals for the implementation of the studied intervention, as well as recommendations for future research and analyses, have been given.  相似文献   
2.
Since the devolution of welfare policymaking to the states after the passage of the 1996 Personal Responsibility and Work Opportunity Reconciliation Act, there has been contentious debate about drug testing welfare applicants. Beyond elite rhetoric and debate points about the implications of welfare drug testing, extant research remains limited insofar as providing theoretical understanding about what factors influence state proposal of legislation requiring welfare applicants to submit to drug tests. I develop and test expectations that derive from research on welfare attitudes, social construction theory, and policy design—specifically, hypotheses that the proportion of blacks on state temporary assistance for needy families caseloads, as well as state‐aggregate levels of symbolic racism, significantly influence state proposal of drug testing legislation. My multilevel analysis of every state proposal of welfare drug testing legislation from 2008 to 2014 yields strong evidence in support of these hypotheses and paints a more complete picture of the influence of racial attitudes on state welfare policymaking. Specifically, while much research finds evidence of institutional racial biases in the implementation of welfare policy, the evidence presented herein shows that these biases, as well as public biases, influence policymaking at the proposal stage. Implications of these findings are discussed in light of recent significant electoral gains made by Republicans in state legislatures.  相似文献   
3.
中国古代书画,因其年代久远,递藏情况复杂,多数屡经裁切割补、修复重装,故而有很多历史信息或被叠摞或被遮蔽,导致今人不能以肉眼直接观察而获得,而纸绢接补,墨迹、颜料、印鉴的残损也为书画研究者带来诸多悬而未决的问题。近年来,高光谱技术作为一种非侵入式的光谱成像技术,已逐步应用于各类彩绘文物中,该技术可为中国古代书画研究和保护提供更丰富的信息。本工作以文献调研为基础,简要介绍了高光谱成像的原理及技术特点,对高光谱技术在中国古代书画研究的实践进行总结,梳理了国内外研究者利用高光谱技术在书画、档案及相关彩绘文物的增强显示、物质识别、虚拟修复方面的应用案例,以期为相关研究者提供参考借鉴。  相似文献   
4.
5.
Timber structures can be degraded during their life both by structural problems and by biological degradation factors like fungi and insects. The occurrence of those biodegradation agents could lead to a loss of their structural integrity, in the absence of appropriate maintenance. An early assessment of the decay is even more important when the wooden structures are part of historical buildings, in the interest of conservation of cultural heritage.

This article presents an application of microwave reflectometry for the in situ evaluation of timber structures. The measurement system allows detecting anomalies inside the material in a non-destructive and non-invasive manner.

The reflection coefficient is measured by means of a vector network analyzer (VNA) using a double-ridge antenna which transmits the continuous-wave (CW) microwave signal and receives the signal reflected by the material under investigation.

Measurements on laboratory models demonstrated the feasibility of the method. Results obtained on timber beam sections, compared with the findings of traditional investigation methodologies, demonstrate the potentiality of microwave reflectometry, suggesting its possible usefulness during the diagnostic phase as a non-invasive tool for preliminary screening.  相似文献   

6.
荀悦在前人的基础上 ,对历史认识的目的、方法、思维方式、检验标准等提出了许多有价值的见解。他阐明以史为鉴的必要性 ,将历史认识与取鉴资治有机结合起来 ;强调认识历史要透过现象看本质 ,通过区分类例 ,由此及彼 ,知微察著 ,去伪存真 ,获得对历史的理性认识 ;指出应以发展变易的观点审视历史 ,不能墨守成规 ,应当因时立制 ,分析事物时应看到其内部相互对立而又相互联系的不同方面 ;要求以儒家思想作为考察历史的理论原则 ,将主观认识与客观事实相参验 ,以真实作为检验历史认识的标准。荀悦的历史认识论值得认真加以总结  相似文献   
7.
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   
8.
Archaeometric research on glass artefacts is continuously evolving and is converging towards a multidisciplinary research domain where different types of techniques are applied depending on the questions asked and the circumstances involved. The technique described in this work is optical spectroscopy. The benefit of this technique being the possibility of building up a knowledge database for a large amount of material in a relatively short period of time and with a relatively limited budget. This is of particular interest for the investigation of extensive and/or unexplored glass collections where a first-line analysis of artefacts could facilitate the selection of material needing further and more detailed examination.  相似文献   
9.
同步辐射X射线荧光(SRXRF)是一种重要的成分分析方法,具有无损、微区、准确、快速的特点。本文利用SRXRF法,分析了不同窑口青白瓷胎的成分,并以陶瓷参考样校正了所测数据。经多元统计分析,发现Rb、Sr、Zn、Mn、Cu、TFe2O3、K2O、Na2O等元素含量具有明显的产地特征,表明SRXRF在古青白瓷鉴定中有着较为理想的应用前景。  相似文献   
10.
为了解故宫博物院藏文物“紫檀木边点翠金质山水图围屏”屏心的制作工艺,使用X射线荧光光谱仪、拉曼光谱仪、红外光谱仪及数码显微镜对文物进行检测,明确了屏风所用材质:满铺“卍”字纹点翠为基底,大面积山体使用纯金打造,细节装饰配件则用金银合金、金银铜合金和银等金属材料制成,金质嵌件用金属丝拴结的方式与点翠基底相连接。笔者以科学技术分析为依托,确定了屏风的制作工艺为:制作木板底纹—点翠—制作金属嵌件—金属部件组装固定。针对点翠脱落严重、灰尘堆积严重、金属部件脱落、点翠基底开裂等伤况,对文物进行了点翠加固、除尘、金属部件加固、基底修复四个步骤完成修复。此修复研究为了解清代宫廷大型屏风的制作工艺提供了实践依据,并为后期同类文物的修复提供经验支持。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号