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31.
Abstract

Active learning techniques are being use with increasing frequency in the classroom and more time is being dedicated to designing and implementing them. However, the literature still suffers from a lack of rigorous empirical methods to test the effects of simulations. Most of the claimed benefits of utilizing simulations, and other active learning techniques, are improved soft skills and higher order thinking like empathy, confidence, public-speaking abilities, and interpersonal skills—all of which don’t lend themselves well to scientific measurement. This gap in the literature is especially troubling considering that time spent using simulations is time not spent using other methods. This article seeks to test the differing impacts of simulations versus traditional lectures over the long-term using a simple 30-minute simulation and rigorous experimental methods. The most important results show that students learn more initially from a lecture, but that students who were exposed to the simulation were better able to retain that information over the long-term.  相似文献   
32.
Local authorities in Great Britain are required to ensure that their electoral registers are as accurate and complete as possible. To this end, Household Enquiry Forms (HEFs) are mailed to all properties annually to collect updated details from residents, and any eligible unregistered residents will subsequently be invited to register to vote. Unfortunately, HEF nonresponse is pervasive and costly. Using insights from behavioural science, we modified letters and envelopes posted to households as part of the annual canvass, and evaluated their effects using a randomised controlled trial across two local authorities in England (N=226,528 properties). We find that modified materials – particularly redesigned envelopes – significantly increase initial response rates and savings. However, we find no effects on voter registration. While certain behavioural interventions can improve the efficiency of the annual canvass, other approaches or interventions may be needed to increase voter registration rates and update voter information.  相似文献   
33.
生产力是少数民族社会发展的最终决定力量;科学技术是第一生产力,是推动少数民族社会全面进步的伟大杠杆。我国少数民族社会必须通过科技建设与技术创新、民族教育的建设与创新、管理创新、民族文化的创新和发展,实现生产力的跨越式发展,促进少数民族经济社会的全面发展。  相似文献   
34.
赵相忠 《桂海论丛》2006,22(2):68-71
文章在对广西服务业发展现状、存在问题、面临的机遇与挑战等进行分析的基础上,系统探讨了广西服务业科技发展的战略选择、重大任务、重点领域、政策与保障措施等有关问题,对于促进广西服务业的进一步发展具有现实意义。  相似文献   
35.
X-ray photoelectron spectroscopy (XPS) is a widely used technique to characterize the surface chemistry of materials. It plays a crucial role in accessing qualitative and quantitative information and in detecting the presence of chemical functional groups on the surface of any material. The forensic methods available to detect and identify elements and organic/inorganic compounds are often destructive, so evidence cannot be re-analyzed. However, XPS allows rapid analysis of samples without damaging them. Recently, an increasing number of forensic researchers have begun to study certain chemical information on fingermarks. In this study, the authors aimed to present the applicability and power of XPS imaging in fingermark analysis which can also provide specific information about the fingermark chemical composition. Herein, monochromated X-ray (Al Kα) spot size was fixed at 50 μm. XPS mapping resulted in the acquisition of spectra at each pixel, in an array of 41 × 30 pixels with a step size of 50 μm. Then, a simple discussion has been made about how the scanned surface spectrum and basic snapshot spectra are used to identify different components at a fingertip of a scanned surface area (~3 mm2). Hence, a fingermark pattern contaminated with caffeine, TiO2, and Pb/PbO deposited on the silicon wafer can be chemically mapped and visualized by XPS using principal component analysis (PCA). Thus, the present study showed the possible applicability of XPS for the identification of illicit drugs of abuse, gunshot residue, and skin care products on latent fingermark by mimicking a crime scene evidence.  相似文献   
36.
Minutiae are small distinguishing features found along every ridge flow, which make each friction ridge print unique. The most common friction ridge prints found at the crime scene are fingerprints; therefore, the most of the minutiae studies are focused exactly on this kind of prints. The authors believe that further examination and enlargement of the palm print database could result in better use of the palm prints for personal identification. We analyzed a total of 160 palm prints from 40 females and 40 males aged between 18 and 70 years from Slovakia. For the evaluation of the minutiae, the area of the hypothenar had to be marked out. The classification of the minutiae used for this study was based on a modified version of the classification system using the total of 13 types of minutiae. The frequency of every minutiae type was calculated and, using the chi-square test with Yates's correction, bilateral and sex differences were assessed. The relationship between the different types of minutiae was examined with Pearson's correlation test. During the initial phases of the identification process, the focus should be on the least common types of minutiae (Y or M and return), which were found not to correlate; thus, their mutual occurrence is random (e.g., overlap—Y or M, crossbar—return, or Y or M—dock). The results of the present study show which specific minutiae types are the most suitable for personal identification. These findings may be beneficial in more effective outcome of the identification process.  相似文献   
37.
This study developed a composite machine learning algorithm for attribution of materials of forensic interest (like ammonium nitrate) to original sources. k-nearest neighbor and random forest models were used for source elimination and classification, respectively, in a two-step, composite algorithm based on particle color, size/shape, and trace element concentration features. Novel approaches for simulation to supplement within-source reference features based on empirically measured multi-lot analyses, an improved hold-one-lot-out method for cross-validation, an assessment of the likelihood of the presence of a reference sample, fusion of the source probabilities from the respective classification models, and the calculation of metrics for assessing ensemble sourcing performance are described. Excellent sourcing predictions were obtained; the sourcing algorithm identified the correct source as the top choice 89% of the time, and the correct source was identified to be an average of 2.7 times more likely than the most likely incorrect source.  相似文献   
38.
39.
《Science & justice》2020,60(2):136-144
The present study investigated the organic gunshot residue (OGSR) background level of police vehicles in Switzerland. Specimens from 64 vehicles belonging to two regional police services were collected and analysed by LC-MS in positive mode. The driver’s and back seats were sampled separately to monitor potential differences between locations and to assess the risks of a suspect being contaminated by OGSR during transportation to a police station.The results showed that most of the 64 vehicles were uncontaminated (44 driver’s seats and 38 back seats respectively). Up to six of the seven targeted compounds were detected in a single sample, once on a driver’s seat and twice on back seats. The contamination frequency generally decreased as the number of compounds detected together increased. The amounts detected were in the low ng range and less than amounts generally detected just after discharge on a shooter. Our data indicated that detecting a combination of four or more compounds on a police vehicle seat appears to be a relatively rare occurrence. The background contamination observed was most probably due to secondary transfer from police officers (e.g. through recent participation in a shooting session or firearm manipulation) or from firearms stored in the vehicles. The present results might be used as a recommendation to minimize contact of a suspect with contaminated surfaces if OGSR is implemented in routine work in parallel to IGSR analysis.  相似文献   
40.
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