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991.
W. Mader 《Discrete Mathematics》2010,310(20):2671-2674
In 1985, Thomassen [14] constructed for every positive integer r, finite digraphs D of minimum degree δ(D)=r which do not contain a vertex x lying on three openly disjoint circuits, i.e. circuits which have pairwise exactly x in common. In 2005, Seymour [11] posed the question, whether an r-regular digraph contains a vertex x such that there are r openly disjoint circuits through x. This is true for r≤3, but does not hold for r≥8. But perhaps, in contrast to the minimum degree, a high regularity degree suffices for the existence of a vertex lying on r openly disjoint circuits also for r≥4. After a survey of these problems, we will show that every r-regular digraph with r≥7 has a vertex which lies on 4 openly disjoint circuits. 相似文献
992.
In this work we will demonstrate the following result: when we have two coupled bistable sub-systems, each driven separately by an external logic input signal, the coupled system yields outputs that can be mapped to specific logic gate operations in a robust manner, in an optimal window of noise. So, though the individual systems receive only one logic input each, due to the interplay of coupling, nonlinearity and noise, they cooperatively respond to give a logic output that is a function of both inputs. Thus the emergent collective response of the system, due to the inherent coupling, in the presence of a noise floor, maps consistently to that of logic outputs of the two inputs, a phenomenon we term coupling induced Logical Stochastic Resonance. Lastly, we demonstrate our idea in proof of principle circuit experiments. 相似文献
993.
近年来,探索新的拓扑量子材料、研究拓扑材料的新奇物理性质成为凝聚态物理领域的一个热点.但是,由于合成、测量等手段的限制,人们难以在真实材料中实现和观测很多理论预言的材料及其物理性质,促使量子模拟日益成为研究量子多体系统的一个重要手段.作为全固态器件,超导量子电路是一个在扩展性、集成性、调控性上都具有巨大优势的人工量子系统,是实现量子模拟的重要方案.本文总结了利用超导量子电路对时间-空间反演对称性保护的拓扑半金属、Hopf-link半金属和Maxwell半金属等拓扑材料的量子模拟,显示出超导量子电路在模拟凝聚态物理系统方面具有广阔前景. 相似文献
994.
995.
This paper presents four new circuit techniques that reduce the parasitic bipolar junction transistor (BJT) effect in digital dynamic logic circuits in partially depleted silicon-on-insulator (PD-SOI) technology. Simulation results have shown the proposed schemes to be effective at various operating voltages. Fully functional test circuits, incorporating some of the proposed techniques, have been designed, fabricated and tested in a 130 nm IBM PD-SOI technology. The measured silicon hardware data validate the simulation predictions and have demonstrated that the new techniques can be easily incorporated to improve the robustness of PD-SOI dynamic logic circuits. 相似文献
996.
M. Schrems M. Knaipp H. Enichlmair V. Vescoli R. Minixhofer E. Seebacher F. Leisenberger E. Wachmann G. Schatzberger H. Gensinger 《e & i Elektrotechnik und Informationstechnik》2008,125(4):109-117
Summary Integration of low voltage analog and logic circuits as well as high-voltage (HV) devices for operation at greater than 5
V enables Smart Power ICs used in almost any system that contains electronics. HVCMOS (High-Voltage CMOS) technologies offer
much lower process cost, if compared to BCD technologies, they enable multiple HV levels on a single chip, and need less effort
when scaling to smaller CMOS technology nodes or when integrating embedded non-volatile memory. In this work we propose a
new 0.35 μm HVCMOS technology that can overcome the previous limitations in drive currents. It can match the low HV chip sizes
(Rdson) of typical BCD processes while maintaining the low process complexity with only 2 mask level adders on top of CMOS.
We also introduce a figure of merit (FOM) for comparing HV technologies. Key elements of making this newly proposed 0.35 μm
HVCMOS so competitive to BCD technologies are discussed and a device lifetime of more than 10 years, operating temperatures
of 150 °C and ESD robustness of 4 kV HBM and higher, as well as the integration of a highly robust embedded EEPROM/Flash technology
is shown. We also provide first verification results of the scalability of the proposed 0.35 μm HVCMOS technology to 0.18
μm and beyond as well as to currents of up to 8 A.
相似文献
997.
GaAs基E/D PHEMT技术单片集成微波开关及其逻辑控制电路 总被引:1,自引:0,他引:1
利用GaAs基 E/D PHEMT 技术单片集成微波开关及其逻辑控制电路的制作工艺和设计方法,采用0.8μm GaAs E/D PHEMT工艺,制备出性能良好的解码器功能内置的DC~10GHz SPDT MMIC,基本实现逻辑电路与开关电路的集成. 开关电路在DC~10GHz内插入损耗小于1.6dB,隔离度大于24dB;整个电路只需要1位控制信号,有效地减少了开关电路的控制端口数目,节省了芯片面积,为GaAs多功能电路的研究奠定了基础. 相似文献
998.
999.
通过虚拟电子实验室EWB软件仿真了非线性系统产生的混沌现象,以Colpitts振荡器电路为例,讨论了在电路中设置不同的元件参数值时产生的不同混沌,并介绍了这种动态混沌在通信系统中作为信息载体的重要应用. 相似文献
1000.
O. Guerra E. Roca F. V. Fernández A. Rodríguez-Vázquez 《Analog Integrated Circuits and Signal Processing》2002,31(2):131-145
This paper presents a methodology for the symbolic analysis of large analog integrated circuits using a hierarchical approach. The drawbacks of previous approaches are solved by the introduction of error-controlled approximation strategies. A proper modeling methodology through the different hierarchical levels allows to combine the optimum techniques for generation of the symbolic expressions and the most efficient numerical techniques for error control. These approximation strategies together with mechanisms for partitioning and union of blocks through the hierarchy yield optimum results in terms of speed, accuracy and complexity of the symbolic results. 相似文献