全文获取类型
收费全文 | 4323篇 |
免费 | 145篇 |
出版年
2020年 | 43篇 |
2019年 | 89篇 |
2018年 | 100篇 |
2017年 | 106篇 |
2016年 | 109篇 |
2015年 | 90篇 |
2014年 | 82篇 |
2013年 | 1286篇 |
2012年 | 132篇 |
2011年 | 115篇 |
2010年 | 148篇 |
2009年 | 143篇 |
2008年 | 88篇 |
2007年 | 111篇 |
2006年 | 98篇 |
2005年 | 58篇 |
2004年 | 52篇 |
2003年 | 52篇 |
2002年 | 59篇 |
2001年 | 67篇 |
2000年 | 50篇 |
1999年 | 61篇 |
1998年 | 62篇 |
1997年 | 48篇 |
1996年 | 57篇 |
1995年 | 44篇 |
1994年 | 48篇 |
1993年 | 44篇 |
1992年 | 41篇 |
1991年 | 37篇 |
1990年 | 24篇 |
1989年 | 42篇 |
1988年 | 37篇 |
1987年 | 50篇 |
1986年 | 37篇 |
1985年 | 41篇 |
1984年 | 50篇 |
1983年 | 43篇 |
1982年 | 31篇 |
1981年 | 42篇 |
1980年 | 52篇 |
1979年 | 45篇 |
1978年 | 27篇 |
1977年 | 50篇 |
1976年 | 34篇 |
1975年 | 37篇 |
1974年 | 23篇 |
1972年 | 25篇 |
1970年 | 23篇 |
1969年 | 22篇 |
排序方式: 共有4468条查询结果,搜索用时 15 毫秒
191.
192.
193.
194.
Philip E. Graves 《Journal of regional science》1976,16(1):107-112
195.
196.
197.
The Geochemical Fingerprint of Tufo Lionato Blocks from the Area Sacra di Largo Argentina: Implications for the Chronology of Volcanic Building Stones in Ancient Rome
下载免费PDF全文
![点击此处可从《Archaeometry》网站下载免费的PDF全文](/ch/ext_images/free.gif)
We use trace element discrimination diagrams to provide a geochemical fingerprint for Tufo Lionato, the volcanic rock most commonly used in the ancient Roman dimension stone technique. Based on the comparison of their geochemical signatures, we identify different rock facies of Tufo Lionato employed since the fourth to third centuries and through the second century bce in the construction of the temples of the Area Sacra di Largo Argentina. These rock facies correspond to two previously identified building stones: Aniene Tuff and Monteverde Tuff, named after their supposed source areas located in the Aniene River Valley and in the homonymous locality of the Tiber River Valley, respectively. However, the results of our study demonstrate previous misidentification of these volcanic rocks in the different construction phases of Temple C, providing a revision of the dating system currently accepted for the diffusion of Tufo Lionato architecture. We show that the Aniene facies has been exploited since the end of the fourth century bce and that it was employed along with Tufo Giallo della Via Tiberina in the podium and staircase of Temple C, whereas observations at Largo Argentina suggest that the ‘Monteverde Tuff’ was only sporadically used in the early phases of the dimension stone construction technique. 相似文献
198.
Recent years have seen an increase in location privacy research, including the application of geomasking procedures. Geographical masks aim to protect privacy and preserve spatial information through the displacement of point data. False identification, or the mistaken association of data with the incorrect person or household, is an unexplored issue in geomasking, despite legal protections against false association. This study introduces a topological framework for assessing identification risk and examines the risk of false identification in four masking techniques: random perturbation, donut masking, and the newer Voronoi and MGRS masking techniques. While Voronoi masking is found to best preserve the clustering properties of a sample of urban foreclosure data, the other three masking techniques result in better protection against correct and false identification. 相似文献
199.
200.
Javier E. Portillo 《Journal of regional science》2018,58(2):451-482
Developers seeking to assemble complementary parcels of land will likely encounter strategic behavior by landowners. Using a property‐level data set from Florida's Department of Transportation covering the period January 2000 to July 2014, I test whether bargaining delays lead to higher final transaction prices. Given the nature of the data, I can compare properties within the same roadway project to estimate the effect of delayed negotiations. My empirical estimates indicate that bargaining delays lead to increased final transaction prices. The magnitude of this effect is approximately 7 percent for the average holdout, however, the effect is nonlinear and diminishes over time. 相似文献