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91.
92.
一种改进的鱼雷实航工作可靠度评定方法 总被引:1,自引:0,他引:1
为了客观准确地评定鱼雷可靠性水平,针对单纯采用成败型或指数型评定鱼雷实航工作可靠度的局限性,根据鱼雷实航功能和动作程序包含成败型和指数型的实际特点,提出了按成败型-指数型串联综合评定鱼雷实航工作可靠度的改进方法。该评定结果是试验样本量、航行总时间、任务时间、成败型和指数型故障数等因素的综合体现,可靠性水平随任务时间变化的显著性受指数型故障的影响相对较大,受成败型故障影响相对较小,评定结果更客观准确,能有效解决单纯按成败型或指数型评定鱼雷可靠性的局限性。 相似文献
93.
根据被动寻的侵彻型制导炸弹的运动特点,设计了能够满足多项约束指标的滑模制导律,并对滑模稳定性进行了证明。仿真结果表明,该制导律能够满足脱靶量和侵彻型制导炸弹对末端攻角及弹道倾角的要求,对参数摄动具有一定的鲁棒性,说明了所设计制导律的有效性。 相似文献
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Automated optimization of service coverage and base station antenna configuration in UMTS networks 总被引:1,自引:0,他引:1
Iana Siomina Peter Varbrand Di Yuan 《Wireless Communications, IEEE》2006,13(6):16-25
Deployment and maintenance of UMTS networks involve optimizing a number of network configuration parameters in order to meet various service and performance requirements. In this article we address automated optimization of service coverage and radio base station antenna configuration. We consider three key configuration parameters: transmit power of the common pilot channel (CPICH), antenna tilt, and antenna azimuth. CPICH power greatly influences coverage. From a resource management point of view, satisfying the coverage requirement using minimum CPICH power offers several performance advantages. In particular, less CPICH power leads to less interference and higher system capacity. Optimal CPICH power, in its turn, is highly dependent on how the other two parameters, tilt and azimuth, are configured at radio base station antennas. Optimizing antenna tilt and azimuth network-wise, with the objective of minimizing the CPICH power consumption, is a challenging task. The solution approach in this article adopts automated optimization. Our optimization engine is a simulated annealing algorithm. Staring from an initial configuration, the algorithm searches effectively in the solution space of possible configurations in order to find improvements. The algorithm is computationally efficient; thus, we can optimize large networks without using excessive computing resources. We present a case study for a UMTS planning scenario in Lisbon. For this network, automated optimization saves up to 70 percent of the CPICH power used in the reference network configuration. In addition, the optimized network configuration offers significant performance improvement in terms of fewer overloaded cells and lower downlink load factor 相似文献
97.
Natale Aiello Giuseppe Di Stefano 《今日电子》2001,(10):34-36
1.技术概述 VK05CFL是一种用于驱动微型荧光灯的自振荡转换器,采用意法半导体的VIPower M3-3专利技术制造而成,允许在同一芯片上集成控制部分和电源级。电源级是一个“发射器开关”,其构成是在级联配置内放置一个双极高压复合晶体管和一个低压MOSFET,因此,在高击穿电 相似文献
98.
Mario Caironi Matt Bird Daniele Fazzi Zhihua Chen Riccardo Di Pietro Christopher Newman Antonio Facchetti Henning Sirringhaus 《Advanced functional materials》2011,21(17):3371-3381
Charge transport is investigated in high‐mobility n‐channel organic field‐effect transistors (OFETs) based on poly{[N,N′‐bis(2‐octyldodecyl)‐naphthalene‐1,4,5,8‐bis(dicarboximide)‐2,6‐diyl]‐alt‐5,5′‐(2,2′‐bithiophene)} (P(NDI2OD‐T2), Polyera ActivInk? N2200) with variable‐temperature electrical measurements and charge‐modulation spectroscopy. Results indicate an unusually uniform energetic landscape of sites for charge‐carrier transport along the channel of the transistor as the main reason for the observed high‐electron mobility. Consistent with a lateral field‐independent transport at temperatures down to 10 K, the reorganization energy is proposed to play an important role in determining the activation energy for the mobility. Quantum chemical calculations, which show an efficient electronic coupling between adjacent units and a reorganization energy of a few hundred meV, are consistent with these findings. 相似文献
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100.
Xingwu Yan Bei Chu Wenlian Li Zisheng Su Tianyou Zhang Fangming Jin Bo Zhao Feng Zhang Di Fan Yuan Gao Taiju Tsuboi Junbo Wang Huajun Pi Jianzhuo Zhu 《Organic Electronics》2013,14(7):1805-1810
We have fabricated an improved organic photovoltaic (OPV) cell in which organic heterointerface layer is inserted between indium-tin-oxide (ITO) anode and copper-phthalocyanine (CuPc) donor layer in the conventional OPV cell of ITO/CuPc/fullerene (C60)/bathophenanthroline (Bphen)/Al to enhance the power conversion efficiency (PCE) and fill factor (FF). The inserted ITO-buffer layer consists of electron-transporting layer (ETL) and hole-transporting layer (HTL). We have changed the ETL and HTL materials variously and also changed their layer thickness variously. It is confirmed that ETL materials with higher LUMO level than the work function of ITO give low PCE and FF. All the double layer buffers give higher PCE than a single layer buffer of TAPC. The highest PCE of 1.67% and FF of 0.57% are obtained from an ITO buffer consisted of 3 nm thick ETL of hexadecafkluoro-copper-phthalocyanine (F16CuPc) and 3 nm thick HTL of 1,1-bis-(4-methyl-phenyl)-aminophenylcyclohexane (TAPC). This PCE is 1.64 times higher than PCE of the cell without ITO buffer and 2.98 times higher than PCE of the cell with single layer ITO buffer of TAPC. PCE is found to increase with increasing energy difference (ΔE) between the HOMO level of HTL and LUMO level of F16CuPc in a range of ΔE < 0.6 eV. From the ΔE dependence of PCE, it is suggested that electrons moved from ITO to the LUMO level of the electron-transporting F16CuPc are recombined, at the F16CuPc/HTL-interface, with holes transported from CuPc to the HOMO level of HTL in the double layer ITO buffer ETL, leading to efficient extraction of holes photo-generated in CuPc donor layer. 相似文献