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Yi‐Hong Liao BS Jae‐Sang Hyun PhD Michael Feller MS Tyler Bell PhD Ian Bortins BS James Wolfe MS David Baldwin PhD Song Zhang PhD 《Journal of forensic sciences》2021,66(1):112-128
The forensic science community raised the need for improved evidence recognition, collection, and visualization analytical instrumentation for field and laboratory use. While the 3D optical techniques for imaging static objects have been extensively studied, there is still a major gap between current knowledge and collecting high‐quality footwear and tire impression evidence. Among optical means for 3D imaging, digital fringe projection (DFP) techniques reconstruct 3D shape from phase information, achieving camera‐pixel spatial resolution. This paper presents a high‐resolution 3D imaging technology using DFP techniques dedicated to footwear and tire impression capture. We developed fully automated software algorithms and a graphical user interface (GUI) that allow anyone without training to operate for high‐quality 3D data capture. We performed accuracy evaluations and comparisons comparing with the commercial high‐end 3D scanner and carried out qualitative tests for various impressions comparing with the current practices. Overall, our technology achieves similar levels of accuracy and resolution with a high‐end commercially available 3D scanner, while having the merits of being (1) more affordable; (2) much easier to operate; and (3) more robust. Compared with the current practice of casting, our technology demonstrates its superiority because it (1) is non‐destructive; (2) collects more evidence detail than casts, especially when an impression is fragile; (3) requires less time and money to collect each piece of evidence; and (4) results in a digital file that can easily be shared with other examiners. 相似文献
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Darrell O. Ricke Ph.D. Philip Fremont‐Smith M.S. James Watkins B.S. Sara Stankiewicz M.S. Tara Boettcher B.S. Eric Schwoebel Ph.D. 《Journal of forensic sciences》2019,64(5):1468-1474
High‐throughput sequencing (HTS) of large panels of single nucleotide polymorphisms (SNPs) provides an alternative or complimentary approach to short tandem repeats (STRs) panels for the analysis of complex DNA mixture forensic samples. For STRs, methods to estimate individual contribution concentrations compare capillary electrophoresis peak heights, peak areas, or HTS allele read counts within a mixture. This article introduces three approaches (mean, median, and slope methods) for estimating individual DNA contributions to forensic mixtures for HTS/massively parallel sequencing (MPS) SNP panels. For SNPs, the major:minor allele ratios or counts, unique to each contributor, were compared to estimate contributor proportion within the mixture using the mean, median, and slope intercept for these alleles. The estimates for these three methods were typically within 5% of planned experimental contributions for defined mixtures. 相似文献
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President Trump encouraged bad state actors within the administrative state to contribute to inequities for civilians. We highlight how Trump's actions and rhetoric led to increased individual, institutional, and systemic racism and violence. As a response to this increased violence and rhetoric, we discuss the role civilians (including professional athletes) played in engaging in protests and the 2020 election. Given that more individuals voted in that election cycle, we emphasize the importance for public administration to adapt, evolve, and engage with new actors concerned with administrative action or inaction. 相似文献
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David James Gill 《Diplomacy & Statecraft》2013,24(3):451-470
Existing accounts of British efforts to achieve a nuclear non-proliferation treaty between 1964 and 1968 largely overlook the later stages of decision making within the Labour government. Scrutiny of previously classified sources reveals that a desire for entry into the European Economic Community had a much larger influence on the content and conduct of British non-proliferation policy than previously suggested. By 1967, Prime Minister Harold Wilson sought a secondary role in treaty negotiations, and left the running to the superpowers. This avoided unnecessary conflict with the countries of the Community, resentful of the Treaty's discriminatory terms, and helped to protect Britain's application to join the EEC. Although this bid was unsuccessful, ambitions for future membership continued to influence non-proliferation policy in 1968. Indeed, a desire for future entry into the EEC helps to explain why Britain became the first nuclear weapon state to ratify the Treaty. 相似文献
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James W Dean 《Third world quarterly》2013,34(3):461-482
Over the past two years Ecuador, El Salvador and Guatemala have adopted the US dollar as a legal currency in their countries. Several other Latin American countries, including Argentina, are currently discussing dollarisation. In this policy paper we look at the existing evidence for answers to two basic questions. First, under what general circumstances might dollarisation make sense? Second, are there clearly differentiated winners and losers from dollarisation and, if so, can we identify them, so that policy can take these political economy factors into consideration? Our review of the evidence demonstrates that there are consistent patterns of distributional effects, both positive and negative, from the choice of exchange rate regime. These effects are presently not considered in exchange rate policy decision making, but should be. While the effects are not as pronounced as those from major trade liberalisation agreements, they are significant. Ways to cushion the effects of exchange rate regime choice should be considered in the future by policy makers. Moreover, we find that dollarisation is embedded in the politics of the region. Dollarisation is often sold as a substitute for the deeper institutional reforms needed to improve economic performance and distribution in Latin America. 相似文献