全文获取类型
收费全文 | 29251篇 |
免费 | 4179篇 |
国内免费 | 2392篇 |
专业分类
电工技术 | 3863篇 |
技术理论 | 1篇 |
综合类 | 3657篇 |
化学工业 | 522篇 |
金属工艺 | 500篇 |
机械仪表 | 2440篇 |
建筑科学 | 283篇 |
矿业工程 | 526篇 |
能源动力 | 267篇 |
轻工业 | 306篇 |
水利工程 | 176篇 |
石油天然气 | 591篇 |
武器工业 | 633篇 |
无线电 | 9095篇 |
一般工业技术 | 1788篇 |
冶金工业 | 311篇 |
原子能技术 | 192篇 |
自动化技术 | 10671篇 |
出版年
2024年 | 84篇 |
2023年 | 584篇 |
2022年 | 924篇 |
2021年 | 952篇 |
2020年 | 897篇 |
2019年 | 650篇 |
2018年 | 647篇 |
2017年 | 929篇 |
2016年 | 1000篇 |
2015年 | 1330篇 |
2014年 | 1847篇 |
2013年 | 1678篇 |
2012年 | 2388篇 |
2011年 | 2444篇 |
2010年 | 1864篇 |
2009年 | 1804篇 |
2008年 | 1954篇 |
2007年 | 2372篇 |
2006年 | 2016篇 |
2005年 | 1743篇 |
2004年 | 1371篇 |
2003年 | 1121篇 |
2002年 | 869篇 |
2001年 | 795篇 |
2000年 | 635篇 |
1999年 | 551篇 |
1998年 | 397篇 |
1997年 | 379篇 |
1996年 | 278篇 |
1995年 | 250篇 |
1994年 | 211篇 |
1993年 | 186篇 |
1992年 | 126篇 |
1991年 | 100篇 |
1990年 | 89篇 |
1989年 | 71篇 |
1988年 | 65篇 |
1987年 | 26篇 |
1986年 | 20篇 |
1985年 | 27篇 |
1984年 | 22篇 |
1983年 | 20篇 |
1982年 | 17篇 |
1981年 | 16篇 |
1980年 | 14篇 |
1979年 | 8篇 |
1978年 | 5篇 |
1977年 | 5篇 |
1976年 | 8篇 |
1975年 | 5篇 |
排序方式: 共有10000条查询结果,搜索用时 78 毫秒
1.
引入句法依存信息到原方面术语,提出一种新的方面术语表示方法,利用Glove词向量表示单词以及单词与单词之间的依存关系,构造出包含句法依存信息的依存关系邻接矩阵和依存关系表示矩阵,利用图卷积神经网络和多头注意力机制将句法依存信息融入到方面术语中,使得方面术语表达与上下文结构高度相关。将改进后的方面词术语表示替换到现有模型后,模型泛化能力得到有效提升。对比试验和分析结果表明:该方法具有有效性和泛化性。 相似文献
2.
3.
Liudmila Zakharova Viktoria Sharova Marina Izvolskaia 《International journal of molecular sciences》2021,22(1)
Different aspects of the reciprocal regulatory influence on the development of gonadotropin-releasing hormone (GnRH)-producing- and immune systems in the perinatal ontogenesis and their functioning in adults in normal and pathological conditions are discussed. The influence of GnRH on the development of the immune system, on the one hand, and the influence of proinflammatory cytokines on the development of the hypothalamic-pituitary-gonadal system, on the other hand, and their functioning in adult offspring are analyzed. We have focused on the effects of GnRH on the formation and functional activity of the thymus, as the central organ of the immune system, in the perinatal period. The main mechanisms of reciprocal regulation of these systems are discussed. The reproductive health of an individual is programmed by the establishment and development of physiological systems during critical periods. Regulatory epigenetic mechanisms of development are not strictly genetically controlled. These processes are characterized by a high sensitivity to various regulatory factors, which provides possible corrections for disorders. 相似文献
4.
5.
《Ceramics International》2022,48(4):5066-5074
We studied the morphological nature of various thin films such as silicon carbide (SiC), diamond (C), germanium (Ge), and gallium nitride (GaN) on silicon substrate Si(100) using the pulsed laser deposition (PLD) method and Monte Carlo simulation. We, for the first time, systematically employed the visibility algorithm graph to meticulously study the morphological features of various PLD grown thin films. These thin-film morphologies are investigated using random distribution, Gaussian distribution, patterned heights, etc. The nature of the interfacial height of individual surfaces is examined by a horizontal visibility graph (HVG). It demonstrates that the continuous interfacial height of the silicon carbide, diamond, germanium, and gallium nitride films are attributed to random distribution and Gaussian distribution in thin films. However, discrete peaks are obtained in the brush and step-like morphology of germanium thin films. Further, we have experimentally verified the morphological nature of simulated silicon carbide, diamond, germanium, and gallium nitride thin films were grown on Si(100) substrate by pulsed laser deposition (PLD) at elevated temperature. Various characterization techniques have been used to study the morphological, and electrical properties which confirmed the different nature of the deposited films on the Silicon substrate. Decent hysteresis behavior has been confirmed by current-voltage (IV) measurement in all the four deposited films. The highest current has been measured for GaN at ~60 nA and the lowest current in SiC at ~30 nA level which is quite low comparing with the expected signal level (μA). The HVG technique is suitable to understand surface features of thin films which are substantially advantageous for the energy devices, detectors, optoelectronic devices operating at high temperatures. 相似文献
6.
Single-cell RNA-sequencing (scRNA-seq) is a rapidly increasing research area in biomedical signal processing. However, the high complexity of single-cell data makes efficient and accurate analysis difficult. To improve the performance of single-cell RNA data processing, two single-cell features calculation method and corresponding dual-input neural network structures are proposed. In this feature extraction and fusion scheme, the features at the cluster level are extracted by hierarchical clustering and differential gene analysis, and the features at the cell level are extracted by the calculation of gene frequency and cross cell frequency. Our experiments on COVID-19 data demonstrate that the combined use of these two feature achieves great results and high robustness for classification tasks. 相似文献
7.
随着人脸识别技术的不断进步以及人脸卡口的大范围且密集的部署, 本文针对团伙犯罪案件侦察这一应用场景, 对人脸卡口数据进行深入挖掘, 探究其中行人间的共现关系, 获取所关注的嫌疑人的现实社交网络, 锁定团伙其余人员. 经过实验比对和论证, 本文使用Chinese Whispers聚类算法对行人节点进行识别, 通过Faiss加速邻接边的构建, 加速图的初始化步骤, 解决其聚类效率低下的问题. 在此基础上, 使用共现频次和Apriori算法中的置信度挖掘行人间的共现关系, 构建行人共现关系图谱. 相似文献
8.
5G蜂窝网络发展迅猛,其覆盖面积将逐渐增大,因此使用5G蜂窝网络进行定位是有研究潜力的研究方向。本文提出一种新的深度学习技术来实现高效、高精度和低占用的定位,以代替传统指纹定位过程中繁重的指纹库生成以及距离计算。该方法建立了一个特殊的卷积神经网络,并根据5G天线信号的接收信号强度指示、相位和到达角等特征量,选择合适的输入数据格式构造样本组建训练集,对该卷积神经网络进行训练。训练得到的卷积神经网络可以替代指纹定位中的庞大指纹库,非常有利于直接在5G移动设备端实现定位。虽然卷积神经网络在训练过程中需要大量时间,但在训练完毕后直接进行分类定位的速度非常快,可以保障定位实现的实时性。本文所实现的卷积神经网络权重与偏置所占内存不到0.5 MB,且能够在实际应用环境中以95%的定位准确率以及0.1 m的平均定位精度实现高精度定位。 相似文献
9.
10.
In this paper, we present LinkingPark, an automatic semantic annotation system for tabular data to knowledge graph matching. LinkingPark is designed as a modular framework which can handle Cell-Entity Annotation (CEA), Column-Type Annotation (CTA), and Columns-Property Annotation (CPA) altogether. It is built upon our previous SemTab 2020 system, which won the 2nd prize among 28 different teams after four rounds of evaluations. Moreover, the system is unsupervised, stand-alone, and flexible for multilingual support. Its backend offers an efficient RESTful API for programmatic access, as well as an Excel Add-in for ease of use. Users can interact with LinkingPark in near real-time, further demonstrating its efficiency. 相似文献