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1.
李桁 《思想战线》2002,28(3):111-116
文化研究的基本思路大致可以这样概括 :1 文化首先是一个特定群体共同拥有的意义系统 ,它最基本的功能就是确立和强化一个特定群体 ;文化发展的途径是通过个体与群体的冲突 ,生成新的符号系统 ,乃至生成新的内在法则。 2 文化是一个开放的能量交换系统 ,它服从于热力学第一定律和热力学第二定律 ;任何文化现象都是直接或间接地根据这两个定律服务于能量的转换 ;心理能量是能量摄取和转换水平的关键 ,但是心理能量的开发不是技术性的 ,而是象征性的。 3 人文科学的非线性特征 ,要求田野工作应该是一个多学科专家共同参与进行的系统工程  相似文献   
2.
目的建立泥土中植物花粉的提取和检验方法。方法用去二甲苯、18%盐酸溶液处理提取泥土中的花粉 ,然后用扫描电镜进行检验。结果从不同的泥土中检出不同花粉。结论本方法能有效分离提取泥土中花粉。对其它混合物中花粉的提取有参考价值。本文介绍一种泥土中花粉提取的简捷方法 ,以及利用扫描电镜 /能谱仪对提取的植物花粉进行检验的方法。  相似文献   
3.
研究胚兔的牙囊发育生物行为与人的牙囊发育是否相似 ,为人口腔疾病的研究提供模拟实验动物模型 ,采用光镜、电镜及激光扫描共聚焦显微镜对 4 3只胚兔的牙囊发育过程进行形态学观察。结果显示 ,牙囊来源于外胚间质 ,通过胚胎诱导形成牙支持组织 ,分化产生成牙骨质细胞、成骨细胞、成纤维细胞 ,形成牙骨质、固有牙槽骨、牙周韧带及其基质 ,对牙齿发育阶段具有保护和稳定作用 ,调控未来形成的牙周结构 ,在早期发育阶段首先出现 ,与人牙囊发育基本相似 ;最终牙囊在牙冠的顶部形成索引带 ,诱导继承牙萌出 ,在牙冠的根部形成牙支持组织 ,一部分牙囊细胞有程序性细胞死亡 ,以维持牙囊发育期内环境的生理平衡  相似文献   
4.
周期可变的交通灯自动管理   总被引:2,自引:0,他引:2  
对道路交通拥挤,秩序混乱,特别是交叉路口经常出现拥堵的情况,通过运用先进的计算机控制技术,可以从很大程度上解决这一突出问题,大大提高市区车辆通行能力,从而提高全社会的经济效益和社会效益。  相似文献   
5.
多相位信号灯的优化——可变车道灯的设置   总被引:2,自引:0,他引:2  
文章对多相位信号灯交叉路口的交通情况进行了简要分析,认为只有设置可变车道灯才可能解决平面交叉路口的拥堵问题.并对设置可变车道灯的可行性进行了分析.  相似文献   
6.
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   
7.
ABSTRACT

Growing in range and urgency, humanitarian needs now pose increasingly acute questions for national security policy formulation. Whether over forced migration, food scarcity or nefarious electronic penetration, state security preferences face uneasy accommodations with individual needs be it for child survival, basic sustenance or rights to privacy. This paper deliberates a further field of increasingly apparent value contest: that involving the transfer, diversion and lethal use of small arms and light weapons (SALW). After outlining the scale of this phenomenon, existing regulatory mechanisms over SALW transfers are assessed. It is argued that these controls are inadequate, a deficiency that is embedded within a range of inter-linked disjunctions. They are outlined in a model that is evaluated against empirical findings. Where SALW control inadequacy is causally connected to the disjunctive model, it is argued, current levels of SALW-induced casualties are unlikely to abate. The paper concludes by considering feasible options for enhanced management of global SALW proliferation.  相似文献   
8.
Gunshot residue (GSR) analysis and their interpretation provide crucial information on a criminal investigation involving the use of firearms. To date, several approaches have been proposed for the implementation of a combined sampling and analysis of inorganic (IGSR) and organic GSR (OGSR). However, it is not clear at this stage if concurrent analyses of both types of residue might be detrimental to the analysis of IGSR currently applied in forensic laboratories. Thus, this work aims to compare and evaluate three different protocols for the combined collection and analysis of IGSR and OGSR. These methods, respectively, involve the use of a modified stub (with two halves, one for the detection of IGSR and the other for the analysis of OGSR); the sequential recovery of GSR with two stubs mounted with different adhesives (double-sided carbon tape and Tesa® TACK) and the sequential analysis of IGSR and OGSR from a single carbon stub following carbon deposition. The detection of IGSR was carried out using SEM-EDX, while OGSR analysis was performed using ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS). Obtained results for experiments performed using Geco Sinoxid® ammunition indicated that sequential analysis was the most suitable protocol for the combined collection and analysis of both IGSR and OGSR. A higher number of inorganic (characteristic and consistent) particles and higher concentrations of ethylcentralite, N-nitrosodiphenylamine, diphenylamine, and nitroglycerin were recovered with this method.  相似文献   
9.
Determining the application sequence of hand-written pen ink and printer toner lines has attracted significant interest in questioned document examination. This study uses coaxial light to determine line-crossing sequences, with intersections observed under a VSC600 forensic document workstation and a Leica M205A Stereo-microscope. Results show that reflected light at intersections and color contrast between intersections and nonintersections was observed when a hand-written ink line passes over a toner line, while a toner line passing over a written line appeared dull, with no color contrast. The procedure was tested under a range of conditions, such as types of writing pens and laser printers, the writer, and writing pressure, with the latter playing an important role in the evaluation. To validate the results, a 90% detection rate and 98% accuracy rate were achieved from 50 samples of blind testing, which is more effective than optical microscopy.  相似文献   
10.
朱墨时序鉴定常见的检验方法包括显微检验法、减层法及光谱法等,其中最基础也是最被普遍使用的方法是显微检验法。通过对显微镜检验在朱墨时序鉴定中的技术要点进行讨论,阐述如何通过选择不同的显微镜,调整放大倍率、照明方式、观察方式及运用共聚焦等技术手段达到最佳观察效果和检验图片。总结了朱墨时序显微镜检验所依据的表观特征及其观察和分析要点,希望对朱墨时序鉴定实践起到积极的指导作用。  相似文献   
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