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   1518篇
  免费   69篇
各国政治   95篇
工人农民   62篇
世界政治   90篇
外交国际关系   102篇
法律   922篇
中国政治   22篇
政治理论   283篇
综合类   11篇
  2024年   39篇
  2023年   164篇
  2022年   23篇
  2021年   49篇
  2020年   38篇
  2019年   46篇
  2018年   44篇
  2017年   60篇
  2016年   65篇
  2015年   40篇
  2014年   55篇
  2013年   187篇
  2012年   64篇
  2011年   47篇
  2010年   49篇
  2009年   48篇
  2008年   49篇
  2007年   62篇
  2006年   48篇
  2005年   54篇
  2004年   39篇
  2003年   35篇
  2002年   42篇
  2001年   20篇
  2000年   20篇
  1999年   23篇
  1998年   14篇
  1997年   11篇
  1996年   7篇
  1995年   14篇
  1994年   10篇
  1993年   3篇
  1992年   20篇
  1991年   10篇
  1990年   6篇
  1989年   11篇
  1988年   8篇
  1987年   6篇
  1986年   7篇
  1985年   6篇
  1984年   4篇
  1983年   8篇
  1982年   4篇
  1981年   2篇
  1980年   4篇
  1975年   3篇
  1973年   2篇
  1969年   3篇
  1966年   3篇
  1955年   1篇
排序方式: 共有1587条查询结果,搜索用时 9 毫秒
151.
152.
Let’s suppose we were in the early Twentieth Century,trying to answer the question:What will be the most important things that will happen in this century?You may think about the"rise of the United States,"or the long-lived British Empire.  相似文献   
153.
Human rights merit global attention in the current era of globalization.The realization and protection of human rights is an important part of the process of global governance.Meanwhile,global governance  相似文献   
154.
This study examines the network structure of policy learning in the C40 Cities Climate Leadership Group, which is a network of the world??s largest cities committed to tackling climate change issues. Among forty members and nineteen affiliate members, we ask the question with whom do cities learn and why? How are policy-learning relationships associated with cities?? multi-stakeholder governing body, policy performance, and cultural similarities? While studies on learning have analyzed conditions facilitating learning, quantitative studies of local government learning in global networks are rare. To facilitate the investigation into learning, we conceptualize learning as a process comprising information seeking, adoption and policy change, and focus on information seeking as the foundation step in the learning process. This social network analysis using the exponential random graph model reveals the cities that seek information and those that are information sources are different subgroups. Furthermore, analysis of nodal attributes suggests that transmunicipal learning in the C40 network is facilitated by the presence of a multi-stakeholder governing body; homophily of culture (language and regional proximity); and higher level of climate change policy performance. Creating a multi-stakeholder governing body could ensure participatory representativeness from citizens and relevant stakeholders to enhance climate change policy engagement and decision making as well as policy learning.  相似文献   
155.
This paper discusses the feasibility of EU legal action in the field of electronic identity (eID) within the new distribution of legal competences and the provision of novel legal basis engendered by the Treaty of Lisbon. The article attempts to find a ‘legal anchor’ to the idea of a pan-European electronic identity within EU law, looking at the issues of competences and legal basis. After examining various different areas of competence and the most feasible (and probable) candidates for a legal basis supporting an EU legal framework for eID, the paper argues that the latter should be found in the combination of Article 16 TFEU (concerning the right to the protection of personal data) with Article 3 TUE, and Articles 26 and 114 TFEU (concerning the establishment and functioning of the Internal Market), which also constitute the area of competence where an eID legal initiative can be pursued.  相似文献   
156.
157.
This article suggests that the consequences of the ??fragmentation?? of the European patent system are more dramatic than the mere prohibitive costs of maintaining a patent in force in many jurisdictions. The prevalence of national jurisdictions, which are highly heterogeneous in their costs and practices, over the validity and enforcement of European patents, induces a high level of uncertainty and an intense managerial complexity which reduce both the effectiveness and the attractiveness of the European patent system in its mission to stimulate innovation.  相似文献   
158.
Research in many forensic science fields commonly uses domestic pigs (Sus spp.) as proxies for human remains, due to their physiological and anatomical similarities, as well as being more readily available. Unfortunately, previous research, especially that which compares the decompositional process, has shown that pigs are not appropriate proxies for humans. To date, there has not been any published research that specifically addresses whether domestic pigs are adequate human proxies for the geophysical detection of clandestine graves. As such, the aim of this paper was to compare the geophysical responses of pig cadavers and human donor graves, in order to determine if pigs can indeed be used as adequate human proxies. To accomplish this, ground penetrating radar (GPR) and electrical resistivity tomography (ERT) responses on single and multiple pig cadaver graves were compared to single and multiple human donor graves, all of which are in known locations within the same geological environment. The results showed that under field conditions, both GPR and ERT were successful at observing human and pig burials, with no obvious differences between the detected geophysical responses. The results also showed that there were no differences in the geophysical responses of those who were clothed and unclothed. The similarity of the responses may reflect that the geophysical techniques can detect graves despite what their contents are. The study implications suggest that experimental studies in other soil and climate conditions can be easily replicated, benefiting law enforcement with missing persons cases.  相似文献   
159.
“Touch DNA” is a form of trace DNA that is presumed to be deposited when an individual touches something and leaves behind DNA-containing skin cells, sweat, or other fluids. While touch DNA is often the result of direct contact (i.e., primary transfer), it can also be indirectly transferred between surfaces or individuals (e.g., secondary or tertiary transfer). Even experts cannot distinguish between different types of transfer and do not fully understand which variables affect direct versus indirect transfer or how often each type of transfer occurs. In this study, we utilize an innovative protocol that combines a paired male and female transfer DNA experimental design with an Amelogenin qPCR assay to generate data on primary, secondary, and tertiary DNA transfer. We report frequencies of indirect DNA transfer and also investigate the potential effects of participant age, self-identified ethnicity, and skin conditions on DNA transfer. Out of 22 experimental trials, we detected primary transfer (male + female) in 71% of trials, secondary DNA transfer in 50% of trials, and tertiary DNA transfer in 27% of trials. No significant associations were found between primary DNA transfer and age, self-identified ancestry, or skin conditions, however, all individuals with sloughing skin conditions demonstrated primary DNA transfer and we suggest this variable be explored in larger samples. These results contribute to a better understanding of the conditions under which secondary and tertiary DNA transfer occurs and can be used to propose realistic DNA transfer scenarios in court cases.  相似文献   
160.
The identification of different kinds of watercolor inks is an important work in the field of forensic science. Four different kinds of watercolor ink Spectroscopy data fusion strategies (Fourier Transform Infrared spectroscopy and Raman spectroscopy) combined with a non-linear classification model (Extreme Learning Machine) were used to identify the brand of watercolor inks. The study chose Competitive Adaptive Reweighted Sampling (CARS), Random Frog (RF), Variable Combination Population Analysis-Genetic Algorithm (VCPA-GA), and Variable Combination Population Analysis-Iteratively Retains Informative Variables (VCPA-IRIV) to extract characteristic variables for mid-level data fusion. The Cuckoo Search (CS) algorithm is used to optimize the extreme learning machine classification model. The results showed that the classification capacity of the mid-level fusion spectra model was more satisfactory than that of single Infrared spectroscopy or Raman spectroscopy. The CS-ELM models based on infrared spectroscopy used to recognize the watercolor ink according to brands (ZHENCAI, DELI, CHENGUANG, and STAEDTLER) obtained an accuracy of 66.67% in the test set using all spectral datasets. The accuracy of CS-ELM models based on Raman spectroscopy was 67.39%. The characteristic wavelength selection algorithms effectively improved the accuracy of the CS-ELM models. The classification accuracy of the mid-level spectroscopy fusion model combined with the VCPA-IRIV algorithm was 100%. The data fusion method increased effectively spectral information. The method could satisfactorily identify different brands of watercolor inks and support the preservation of artifacts, paintings, and forensic document examination.  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