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221.
RECORD OF LiU DONG AND HIS ATSATSA COLLECTION   总被引:1,自引:0,他引:1  
Chen  Dan  Geng  Yi 《中国西藏(英文版)》2011,(1):44-51
  相似文献   
222.
王祎 《收藏家》2011,(3):3-9
古代碑帖具有多方面的学术价值和艺术价值,其内容涉及政治经济、宗教哲学、风俗民情、文学艺术等方面,为古代文学、历史学、文字学都提供了大量宝贵的资料,可与历史典籍互相补正。由于年代久远,书翰遗墨传世有限。碑帖保存了各个时代、众多名家的法书墨迹,呈现出各家流派的书法风格,篆、隶、真、草、行五体皆备,实为中国书法艺术的宝库。  相似文献   
223.
熊建平 《收藏家》2011,(9):75-76
刘台子西周墓地位于山东省济南市济阳县曲堤镇刘台子村西约200米的高台上。20世纪70年代末、80年代初中期,山东省考古工作者对墓地进行了3次科学发掘共发掘了5座墓葬,出土了大量的西周时期的青铜器、玉器、陶器等文物。  相似文献   
224.
Gongju, or public offices, controlled by the local gentry class, were the grassroots authorities in rural Guangdong during the late Qing. These offices maintained their own armed forces and usually had powers of administration, tax collection, and self-defense, as well as judicial powers. They were considered the extension of prefecture and county governments. With the authorization of the prefecture and county governments, these offices had the power to deal with important legal cases. Although they came under attack during the 1911 Revolution, these offices were able to recover quickly in different forms. In the late Qing era, local gentry with official titles earned in middle-level or lower-level civil service examinations took the leadership roles in such grassroots offices, but they were replaced by people who had direct control over the armed forces during Republican times.  相似文献   
225.
This paper investigates the competing forces driving the development of renewable energy in the American states. We formulate a framework of state renewable energy politics and develop a set of hypotheses regarding the role of politics, policies, and prices in renewable energy development. We test these hypotheses with a fixed effect vector decomposition model using a panel data set for the U.S. states from 1990 to 2008. The results indicate that renewable energy development is influenced by regulatory institutions, the party affiliations of the governor and legislators, and the professionalism of the legislature, accompanied by the effects of various policy instruments.  相似文献   
226.
This paper focuses on the study of simulations for spatially variable seismic underground motions in U-shaped canyons. First, a canyon ground cross-coherence function based on commonly used coherence function models of flat terrain, is deduced and presented. To further obtain the underground cross-coherence function, a mathematical expression, including its specific deduction process for describing the relationship between coherence functions of multi-support ground and underground motions, is also given in detail and adopted. Then, the key factors (i.e. canyon underground power spectrum density and canyon underground coherence function) for simulating the spatially variable seismic underground motions are obtained by a two-step transferring method from flat-ground to underground soil. Furthermore, a program is coded for generating the spatially variable seismic underground motions. The effectiveness of the generated seismic motions is further verified. Finally, two numerical examples are taken to validate the proposed simulation approach, illustrating the specific characteristics of canyon coherence function. The analysis results show the apparent differences of the simulated seismic motions using the canyon coherence function from those using conventional coherence function models of flat terrain. The proposed approach provides some insights for anti-earthquake analysis of soil-structure interaction or underground structures in canyon topography.  相似文献   
227.
Xu, H.-H., Wang, Y., Tang, P. & Wang, Y., May 2017. A new diminutive euphyllophyte from the Middle Devonian of West Junggar, Xinjiang, China and its evolutionary implications. Alcheringa 41, 524–531. ISSN 0311-5518.

A diminutive euphyllophyte, Douaphyton levigata gen. et sp. nov., is described from the upper Middle Devonian (Givetian) Hujiersite Formation of West Junggar, Xinjiang, China. The plant consists of more than three orders of axis branching, each axis being less than 2 mm wide. The second-order axes are short, laterally and alternately attached to the main axis. The third-order axes are paired and anisotomously divided, bearing the vegetative appendages or the fertile units. The fertile unit consists of a short recurved axis giving off up to four short pedicels along one side, each of which bears one to four pairs of terminal sporangia. Douaphyton has a three-dimensional branching system that has an intermediate form in the evolutionary context of euphyllophytes and lignophytes. It is also proposed that complex branching developed in multiple groups in the Middle Devonian.

*Hong-He Xu [], Yao Wang [], Peng Tang [], Yi Wang [] State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210,008, PR China. Yao Wang [] University of Science and Technology of China. 96 Jinzhai Road, Hefei, Anhui Province, 230,026, PR China.  相似文献   

228.
The Dansirit Formation of the Shemshak Group is well exposed in the Parvar area, near the Rudbarak village, Central Alborz, Iran. It contains abundant well-preserved plant macrofossils belonging to 20 taxa of Equisetales, Marattiales, Filicales, Bennettitales, Cycadales, Corystospermales, Caytoniales, Czekanowskiales, Ginkgoales and Pinales. The new species Caytonia iranica sp. nov. is described. Based on the occurrence of Equisetites beanii, Coniopteris hymenophylloides, Nilssonia sarakhs, Czekanowskia blacki and Pseudoctenis fragilis, an early Middle Jurassic age is suggested for this assemblage.  相似文献   
229.
Wang, Z.H., Bergström, S.M., Zhen, Y.Y., Chen, X. & Zhang, Y.D., 2013. On the integration of Ordovician conodont and graptolite biostratigraphy: New examples from Gansu and Inner Mongolia in China. Alcheringa 37, 510–528. ISSN 0311-5518.

Few Ordovician successions in the world contain both biostratigraphically highly diagnostic conodonts and graptolites permitting an integration between standard biozones based on these fossil groups. The Sandbian Guanzhuang section in the vicinity of Pingliang in the Gansu Province has an outstanding graptolite record through most of the Nemagraptus gracilis and Climacograptus bicornis graptolite biozones. Calcareous interbeds in the succession yield biostratigraphically important conodonts, including some species used for biozonations in Baltoscandia and the North American Midcontinent. Likewise, the middle–upper Darriwilian Dashimen section in the Wuhai region of Inner Mongolia hosts both diverse graptolites of the Pterograptus elegans, Didymograptus murchisoni and lowermost Nemagraptus gracilis biozones, and conodonts of Midcontinent and Baltoscandic types. The distribution patterns of these index fossil groups provide an unusual opportunity to closely correlate conodont and graptolite biozones in the middle to upper Darriwilian to Sandbian interval. For instance, the base of the C. bicornis Biozone is approximately coeval with the base of the Baltoscandic B. gerdae Subbiozone and a level near the middle of the North American P. aculeata Biozone.

Zhi-hao Wang [zhwang@nigpas.ac.cn] Xu Chen [xu1936@gmail.com], and Yuan-dong Zhang [ydzhang@nigpas.ac.cn], Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China; Stig M. Bergström [stig@geology.ohio-state.edu], School of Earth Sciences, Division of Earth History, The Ohio State University, Columbus, OH 43210, USA; Yong Yi Zhen [yongyi.zhen@austmus.gov.au], Australian Museum, 6 College Street, Sydney NSW 2010, Australia.  相似文献   
230.
In recent years, techniques have been developed to explore spatial nonstationarity and to model the entire distribution of a regressand. The former is mainly addressed by geographically weighted regression (GWR), and the latter by quantile regression (QR). However, little attention has been paid to combining these analytical techniques. The goal of this article is to fill this gap by introducing geographically weighted quantile regression (GWQR). This study briefly reviews GWR and QR, respectively, and then outlines their synergy and a new approach, GWQR. The estimations of GWQR parameters and their standard errors, the cross‐validation bandwidth selection criterion, and the nonstationarity test are discussed. We apply GWQR to U.S. county data as an example, with mortality as the dependent variable and five social determinants as explanatory covariates. Maps summarize analytic results at the 5, 25, 50, 75, and 95 percentiles. We found that the associations between mortality and determinants vary not only spatially, but also simultaneously across the distribution of mortality. These new findings provide insights into the mortality literature, and are relevant to public policy and health promotion. Our GWQR approach bridges two important statistical approaches, and facilitates spatial quantile‐based statistical analyses. En los últimos años se han desarrollado diversas técnicas para explorar tanto la heterocedasticidad (o no estacionariedad) espacial, así como para modelar toda la distribución de una variable dependiente. El primer tema ha sido abordado principalmente por la regresión ponderada geográficamente (Geographically Weighted Regression ‐GWR), y el segundo por la regresión por cuantiles (Quantile Regression‐QR). La combinación de ambas técnicas analíticas, sin embargo, ha recibido mucho menos atención. El objetivo de este artículo es llenar dicho vacío mediante la propuesta de una regresión geográficamente ponderada por cuantiles (Geographically Weighted Quantile Regression‐ GWQR). Los autores resumen brevemente las técnicas GWR y QR respectivamente, y luego esbozan sus propiedades sinérgicas. Luego presentan la nueva técnica propuesta: GWQR. Los autores abordan los temas de las estimaciones de los parámetros GWQR y sus errores estándar, el criterio de selección del ancho de banda de la validación cruzada (cross‐validation bandwidth), y la prueba heterocedasticidad espacial. Como ejemplo se aplica GWQR a datos de la tasa de mortalidad como variable dependiente y cinco determinantes sociales como variables independientes para los condados de los Estados Unidos. Los patrones espaciales se presentan en mapas con los resultados del análisis para los percentiles 5, 25, 50, 75, y 95. Los resultados muestran que las asociaciones entre la mortalidad y sus factores determinantes no sólo varían espacialmente, sino también de forma simultánea a través de la distribución de la tasa de mortalidad. Estos nuevos hallazgos coinciden con la literatura de los estudios de mortalidad, y son relevantes para aplicaciones de política pública y promoción de la salud. El enfoque GWQR representa un puente conceptual y metodológico entre dos enfoques estadísticos importantes a la vez que hace más factible el análisis estadístico espacial por cuantiles. 近年来,可用于探讨空间非平稳性和模拟回归变数分布的技术得到发展。前者主要用地理加权回归方法(GWR)处理,后者采用分位数回归(QR)处理。然而对这些分析技术的结合使用却很少关注。本文试图通过提出地理加权分位数回归(GWQR)来填补这一空白。在分别简要回顾了GWR和QR方法的基础上,基于两个方法的协同应用提出了GWQR新方法,进而讨论了GWQR的参数估计、标准误差、带宽选择标准的交叉验证和非平稳性检验。本文将死亡率作为因变量及五个社会因子作为解释变量,进行了美国县域单元的案例研究,绘制了0.05、0.25、0.5、0.75和0.95不同百分位点的分析结果图。研究发现,死亡人数不仅与解释变量的空间分布相关,同时也与其地理分布相关。这些新发现不仅可促进对死亡率相关成果的深入分析,同时也与公共政策和健康促进有关。GWQR方法架构了QR和GWR两种重要统计方法之间的纽带,也促进了基于分位数的空间统计分析方法的发展。  相似文献   
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