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1.
Chong D. Y. R. Lim B. K. Rebibis K. J. Pan S. J. Sivalingam K. Kapoor R. Sun A. Y. S. Tan H. B. 《Advanced Packaging, IEEE Transactions on》2006,29(4):674-682
The recent advancement in high- performance semiconductor packages has been driven by the need for higher pin count and superior heat dissipation. A one-piece cavity lid flip chip ball grid array (BGA) package with high pin count and targeted reliability has emerged as a popular choice. The flip chip technology can accommodate an I/O count of more than five hundreds500, and the die junction temperature can be reduced to a minimum level by a metal heat spreader attachment. None the less, greater expectations on these high-performance packages arose such as better substrate real estate utilization for multiple chips, ease in handling for thinner core substrates, and improved board- level solder joint reliability. A new design of the flip chip BGA package has been looked into for meeting such requirements. By encapsulating the flip chip with molding compound leaving the die top exposed, a planar top surface can be formed. A, and a flat lid can then be mounted on the planar mold/die top surface. In this manner the direct interaction of the metal lid with the substrate can be removed. The new package is thus less rigid under thermal loading and solder joint reliability enhancement is expected. This paper discusses the process development of the new package and its advantages for improved solder joint fatigue life, and being a multichip package and thin core substrate options. Finite-element simulations have been employed for the study of its structural integrity, thermal, and electrical performances. Detailed package and board-level reliability test results will also be reported 相似文献
2.
Many organisations use decision models in their processes such as tables or trees to provide decision support to their operational
divisions. For example, in fault management, customer contact centre operators usually use a decision model in the form of
prescribed interviews. Based on the answers given by customers, the operator navigates through the decision model to reach
an assessment of the problem. In order to achieve customer satisfaction and operational excellence, it is very important to
constantly monitor the performance of a decision model not only on an overall level, but also on the level of individual decisions.
In this paper we present a configurable business process analytics tool, known as the intelligent Universal Service Management
System, that constantly monitors decision data and is capable of optimising the decisions based on high-level business objectives.
We explain the various features of the software and show how it can be used to optimise decision processes. We also show how
we can easily provide a customised version to monitor the performance of provision processes. 相似文献
3.
Shi-Jin Ding Hang Hu Lim H.F. Kim S.J. Yu X.F. Chunxiang Zhu Li M.F. Byung Jin Cho Chan D.S.H. Rustagi S.C. Yu M.B. Chin A. Dim-Lee Kwong 《Electron Device Letters, IEEE》2003,24(12):730-732
For the first time, we successfully fabricated and demonstrated high performance metal-insulator-metal (MIM) capacitors with HfO/sub 2/-Al/sub 2/O/sub 3/ laminate dielectric using atomic layer deposition (ALD) technique. Our data indicates that the laminate MIM capacitor can provide high capacitance density of 12.8 fF//spl mu/m/sup 2/ from 10 kHz up to 20 GHz, very low leakage current of 3.2 /spl times/ 10/sup -8/ A/cm/sup 2/ at 3.3 V, small linear voltage coefficient of capacitance of 240 ppm/V together with quadratic one of 1830 ppm/V/sup 2/, temperature coefficient of capacitance of 182 ppm//spl deg/C, and high breakdown field of /spl sim/6 MV/cm as well as promising reliability. As a result, the HfO/sub 2/-Al/sub 2/O/sub 3/ laminate is a very promising candidate for next generation MIM capacitor for radio frequency and mixed signal integrated circuit applications. 相似文献
4.
W. Lim C. K. Wang 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1996,370(2-3):568-572
The one-dimensional (1D) position-sensitive superheated-liquid-droplet dosimeter (SLDD) has been fabricated and tested in the laboratory. The 1D SLDD is fabricated from a 9.525-mm OD, 6.35-mm ID, 20-cm long, Plexiglas-walled tube filled with a mixture of superheated-liquid Freon droplets and host medium glycerol. Washer-shaped piezoelectric acoustic transducers are positioned at both ends of the tube; they determine the number and positions of the acoustic events when the superheated-liquid droplets evaporate upon neutron irradiation. The SLDD is irradiated with the 137Cs and 60Co γ-sources, as well as 252Cf neutron source to test for its radiation response and spatial resolution. The SLDD based on the Freon-134a superheated-liquid droplets operating at 20°C and 1 atm is found to be ideal for measuring absorbed neutron dose. This study also proves that the positions of the radiation-induced nucleation acoustic events can be linearly determined from the differences in the transmission times received by the acoustic transducers on the 1D SLDD. The spatial resolution of the neutron depth-dose is 1 mm due the finite response time (1 μs) of the piezoelectric acoustic transducers. 相似文献
5.
The effect of high oxide field stress is studied using capacitance-time (C-t) measurements of MOS capacitors. The stress results in parallel shifts of the C-t curve along the time axis. The flatband voltage shift ΔVFB obtained from the initial deep depletion capacitance C(t=0+) follows the same trend as that from the high-frequency C-V characteristics. However, the discrepancy between the two flatband voltages becomes larger as the stress increases due to the effect of interface charges on C-t characteristics. The flatband voltage difference is converted to interface trap density, showing a steady increase of interface trap density with stress, similar to that from low-frequency C-V measurements 相似文献
6.
Han-Kyu Lim Deog Kyoon Jeong KyungTae Kim JunMo Park Han-gyoo Kim 《Communications Magazine, IEEE》2005,43(5):141-148
Network direct attached storage (NDAS) is a network storage architecture that allows direct attachment of existing ATA/ATAPI devices to Ethernet without a separate server. Unlike other architectures such as NAS, SAN, and USB mass storage, no server computer intervenes between the storage and the client hosts. We describe an NDAS disk controller (NDC) amenable to low-cost single-chip implementation that processes a simplified L3/L4 protocol and converts commands between ATA/ATAPI and Ethernet, while the remaining complex tasks are performed by remote hosts. Unlike NAS architectures that use TCP/IP, NDAS uses a TCP-like lean protocol that lends itself well to high-performance hardware realization. Thanks to the simple NDAS architecture and protocol, an NDC implemented on a single 4 mm /spl times/ 4 mm chip in 0.18 /spl mu/m CMOS technology achieves a maximum throughput of 55 Mbytes/s on gigabit Ethernet, which is comparable to that of a high-performance disk locally attached to a host computer. 相似文献
7.
Teik-Cheng Lim 《Journal of Materials Science》2004,39(15):4965-4969
8.
9.
Chun Yang Yin Sharifah Aishah Syed Abdul KadirYing Pei Lim Sharifah Nawirah Syed-AriffinZurinawati Zamzuri 《Fuel Processing Technology》2008
Ash derived from combustion of Malaysian oil palm biomass (empty fruit bunches consisting of fibers) was physically and chemically characterized in order to provide a comprehensive understanding of its specific properties in terms of toxicity, compositions and reusability. Principal analyses conducted include particle size distribution, scanning electron microscopy, elemental dispersive X-ray, elemental analysis, toxicity characteristic leaching procedure (TCLP) as well as thermogravimetric, X-ray diffractometry and Fourier-transform infrared analyses. TCLP result indicated that the oil palm ash (OPA) should not be classified as toxic wastes in terms of heavy metal leachability since leachable copper, cadmium, lead and nickel concentrations were detected below the stipulated leachability limits. It was determined that the OPA contained high amount of potassium as well as presence of silica which implied its suitability to be reused as crude fertilizer or cement replacement material. 相似文献
10.
Rajoo R. Lim S.S. Wong E.H. Hnin W.Y. Seah S.K.W. Tay A.A.O. Iyer M. Tummala R.R. 《Advanced Packaging, IEEE Transactions on》2008,31(2):377-385
A wafer level packaging technique has been developed with an inherent advantage of good solder joint co-planarity suitable for wafer level testing. A suitable weak metallization scheme has also been established for the detachment process. During the fabrication process, the compliancy of the solder joint is enhanced through stretching to achieve a small shape factor. Thermal cycling reliability of these hourglass-shaped, stretch solder interconnections has been found to be considerably better than that of the conventional spherical-shaped solder bumps. 相似文献