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101.
将常规的数字温度仪与压力计通过串行口和计算机连接,构建基于LabVIEW 8.0测定纯液体蒸发焓的虚拟仪器,实现实验数据的动态采集、实时显示、自动绘制p~T曲线并显示曲线方程、自动数据处理和写成结果报告等。应用结果表明:基于LabVIEW构建的测定纯液体蒸发焓的虚拟仪器,免除人工操作的繁琐和人为误差,测定乙醇和苯蒸发焓的相对误差分别为0.86%、-2.97%,提高了测量结果的准确度,且具有界面友好,操作简便和功能易扩展等诸多优点。 相似文献
102.
Mao-Zu Guo Jun Wang Chun-yu Wang Yang Liu 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2009,13(12):1143-1151
TagSNP selection, which aims to select a small subset of informative single nucleotide polymorphisms (SNPs) to represent the
whole large SNP set, has played an important role in current genomic research. Not only can this cut down the cost of genotyping
by filtering a large number of redundant SNPs, but also it can accelerate the study of genome-wide disease association. In
this paper, we propose a new hybrid method called CMDStagger that combines the ideas of the clustering and the graph algorithm,
to find the minimum set of tagSNPs. The proposed algorithm uses the information of the linkage disequilibrium association
and the haplotype diversity to reduce the information loss in tagSNP selection, and has no limit of block partition. The approach
is tested on eight benchmark datasets from Hapmap and chromosome 5q31. Experimental results show that the algorithm in this
paper can reduce the selection time and obtain less tagSNPs with high prediction accuracy. It indicates that this method has
better performance than previous ones. 相似文献
103.
Control of frictional forces is required in many applications of tribology. While the problem is approached by chemical means traditionally, a recent approach was proposed to control the system mechanically to tune frictional responses. We design feedback control laws for a one-dimensional particle array sliding on a surface subject to friction. The Frenkel-Kontorova model describing the dynamics is a nonlinear interconnected system and the accessible control elements are average quantities only. We prove local stability of equilibrium points of the un-controlled system in the presence of linear and nonlinear particle interactions, respectively. We then formulate a tracking control problem, whose control objective is for the average system to reach a designated targeted velocity using accessible elements. Sufficient stabilization conditions are explicitly derived for the closed-loop error systems using the Lyapunov theory based methods. Simulation results show satisfactory performances. The results can be applied to other physical systems whose dynamics is described by the Frenkel-Kontorova model. 相似文献
104.
建筑侧各类可再生能源的应用日益普及,建筑电能耗预测在用能供需平衡、电网稳定运行、尖峰需求响应等方面发挥越来越重要作用。尽管诸多数据驱动模型在能耗预测方面获得广泛应用,当前仍缺乏预测精度高、泛化能力强的短期预测模型。针对该问题,提出一种基于建筑物能耗特点并结合数据挖掘技术的分类集成式能耗预测方法。首先,采用递归特征消除法对数据进行特征筛选,并用模糊C均值聚类算法对训练集数据进行聚类,使用K最邻近法对验证集和测试集数据进行归类;选择5种结合智能优化算法的混合数据驱动模型作为子学习器,分别对每类数据做预测,最后使用多元线性回归法进行结果集成。经3个建筑电力用能案例验证,此集成预测模型精度均优于单个子模型,具有适用不同建筑类型和用能尺度的预测潜力。 相似文献
105.
基于扩展惠更斯-菲涅尔原理和维格纳分布函数(Wigner distribution function,WDF)二阶矩,推导了部分相干扭曲涡旋光束(partially coherent twisted vortex beam,PCTVB)在海洋湍流中传输时的M2因子和角扩展θ(z)。通过数值模拟方法详细研究了海洋湍流对光束M2因子和角扩展θ(z)的影响,结果表明温度方差耗散率ΧT和温度盐度贡献比w越大、动能耗散率ε和各向异性因子ξ越小时对PCTVB的M2因子和角扩展θ(z)的影响越大。此外研究发现,相较于非扭曲涡旋光束(PCVB),PCTVB有更好的抗海洋湍流的能力,且增大拓扑荷数m以及扭曲因子绝对值|μ|后,PCTVB的M2因子和角扩展θ(z)显著减小,光束的抗海洋湍流能力增强。并且增大束腰宽度w0和波长λ,以及减小初始相干长度δηη(η=x,y)同样可以增加光束抗海洋湍流的能力。本文的数值研究结果对海洋光通信具有重要意义。 相似文献
106.
Yin Lifeng Kong Yanggang Guo Mingkang Zhang Xingyu Yan Wenlong Zhang Hua 《Magma (New York, N.Y.)》2023,36(4):651-658
Magnetic Resonance Materials in Physics, Biology and Medicine - This study aims to present a radiomic application in diagnosing the long head of biceps (LHB) tendinitis. Moreover, we evaluated... 相似文献
107.
Ruiqi Li Lian Chen Qin Ji Qing Liang Ying Zhu Wei Fu Tianyou Chen Hongwei Duan Wenshan He Zushun Xu Xiaofang Dai Jinghua Ren 《Advanced functional materials》2023,33(37):2213292
Radiotherapy is identified as a crucial treatment for patients with glioblastoma, but recurrence is inevitable. The efficacy of radiotherapy is severely hampered partially due to the tumor evolution. Growing evidence suggests that proneural glioma stem cells can acquire mesenchymal features coupled with increased radioresistance. Thus, a better understanding of mechanisms underlying tumor subclonal evolution may develop new strategies. Herein, data highlighting a positive correlation between the accumulation of macrophage in the glioblastoma microenvironment after irradiation and mesenchymal transdifferentiation in glioblastoma are presented. Mechanistically, elevated production of inflammatory cytokines released by macrophages promotes mesenchymal transition in an NF-κB-dependent manner. Hence, rationally designed macrophage membrane-coated porous mesoporous silica nanoparticles (MMNs) in which therapeutic anti-NF-κB peptides are loaded for enhancing radiotherapy of glioblastoma are constructed. The combination of MMNs and fractionated irradiation results in the blockage of tumor evolution and therapy resistance in glioblastoma-bearing mice. Intriguingly, the macrophage invasion across the blood-brain barrier is inhibited competitively by MMNs, suggesting that these nanoparticles can fundamentally halt the evolution of radioresistant clones. Taken together, the biomimetic MMNs represent a promising strategy that prevents mesenchymal transition and improves therapeutic response to irradiation as well as overall survival in patients with glioblastoma. 相似文献
108.
109.
The Journal of Supercomputing - We argue the agent’s low generalization problem for searching target object in challenging visual navigation could be solved by "how" and... 相似文献
110.
Sun Kaili Li Yuan Zhang Huyin Guo Chi Yuan Linfei Hu Quan 《The Journal of supercomputing》2022,78(14):16529-16552
The Journal of Supercomputing - In the literature, most previous studies on English implicit inter-sentence relation recognition only focused on semantic interactions, which could not exploit the... 相似文献