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41.
Latent prints are an important evidence for identification. Nowadays, the technical means, the implementation of image processing techniques and the use of database makes it possible to detect and get information from some prints that seem to be useless at first sight. On the other hand, the possibility of using the print as a DNA source has to be considered, so as to double its identifying value. Human skin is a particularly difficult surface for developing this kind of evidences. Although different methods for locating and developing latent fingerprints on the skin have been already described, it has not been found any method, at the revised bibliography, to obtain and develop invisible lipmarks, that is, lipmarks from protective lipstick, or permanent or long-lasting lipstick. The aim of the work that follows is to determine the effectiveness of several reagents for developing invisible lipmarks on the corpses' skin. Preliminary results show that, under the described experimental conditions, the reagents used, Sudan III, Oil Red O and Sudan Black, are effective for obtaining recent latent lip prints on corpse's skin.  相似文献   
42.
A method for the simultaneous determination of cocaine (COC) and cocaethylene (CE) in human hair was developed, using solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS) as analytical technique to identify and quantify the drugs. Selected ion monitoring (SIM) mode was used to obtain higher sensitivity. The deuterated-labeled analogues were used as internal standards. The detector response was linear for the drugs studied over the range 0.4-15 ng/mg, with correlation coefficients higher than 0.995. The coefficients of variation oscillated between 0.65% and 14.18% and the accuracy was in the range from 0.73% to 11.20%. The limits of quantitation and detection were found to be acceptable. Finally, this method was applied to 15 hair samples from cocaine users, obtaining positive results in all cases. The mean concentrations were 5.39 ng/mg (range: 0.43-8.98 ng/mg) for cocaine and 1.11 ng/mg (range: 0.42-2.23 ng/mg) for cocaethylene.  相似文献   
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44.
劳动力市场人才资源的配置问题是小城镇服务业发展中急需解决的重要问题之一。本文从用人单位满意度分析的基础上,采用模糊综合评价法对当前小城镇服务业劳动力需求与人才培养对接问题现状进行了评价,发现劳动力市场人才资源的配置与人才培养供给之间出现了严重的失衡。人才培养只有遵循劳动力市场需求,动态地调整培训方案与体系,才能够健康持续地发展。  相似文献   
45.
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   
46.
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   
47.
Political alternate positions (otherwise known as substitutes) can have important effects on women's abilities to enter politics. Using the case of Nicaragua, this study assesses whether these alternate positions are being used to increase women's political representation or as a tool to undermine women's advancement into positions of power. By examining patterns of women's representation as candidates in the 1996, 2001, and 2006 elections for the National Assembly and as elected officeholders (as both alternates for those assembly members and titleholders), the article analyzes how various political parties are utilizing these alternate positions. Contrary to the conventional wisdom, this study finds no evidence that these alternate positions are used to undermine women's political progress.  相似文献   
48.
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   
49.
“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   
50.
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   
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