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181.
Chua-Chin Wang Chia-Hao Hsu Gang-Neng Sung Yu-Cheng Lu 《Journal of Signal Processing Systems》2012,66(2):87-92
A low power digital signed array multiplier based on a 2-dimensional (2-D) bypassing technique is proposed in this work. When
the horizontally (row) or the vertically (column) operand is zero, the corresponding bypassing cells skip redundant signal
transitions to avoid unnecessary calculation to reduce power dissipation. An 8×8 signed multiplier using the 2-D bypassing
technique is implemented on silicon using a standard 0.18 μm CMOS process to verify power reduction performance. The power-delay
product of the proposed 8×8 signed array multiplier is measured to be 31.74 pJ at 166 MHz, which is significantly reduced
in comparison with prior works. 相似文献
182.
While the market turns to an environment with low profit margins for semiconductor backend operations, it is hard for an independent firm to survive today. Forming strategic alliances or integrating an enterprise's internal firms by means of collaborative planning/operations to gain competitive advantage is inevitable. This paper presents the development of an activity-based costing collaborative production planning system (ABC/CPPS) to help production planners to estimate the manufacturing profit of semiconductor backend turnkey (combined IC assembly and testing) operational services at the early stage of order release to production line in a collaborative context. The estimation is under the real constraints of production resources. A predicate/transition net (Pr/Tr net) is used to simulate and implement the activity-based costing (ABC) model with the dynamic characteristics of a production line incorporated. A financial measure, profit, is used to supplement and indicate the consequence of the planning result and link the view to the enterprise's financial vision. 相似文献
183.
184.
Abstract A numerical technique for integrating the full Navier‐Stokes and diffusion equations through an initial value problem has been used to investigate the time development of a line buoyant source issuing in a density‐stratified environment. The basic physical features and some structures of the interactions of the motion at the intermediate mixing region are obtained. Results show that the stratification tends to inhibit the flow development of the buoyant source and to encourage the formation of a recirculatory vortex on the lower region near the source and the upper region. 相似文献
185.
Fu-Hau Hsu Min-Hao Wu Cheng-Hsing Yang Shiuh-Jeng Wang 《The Journal of supercomputing》2014,70(1):247-268
Digital watermarking technology is primarily the joining of the rightful owner of the protected media. Once the media are suspected to be illegally used, an open algorithm can be used to extract the digital watermark for the purpose of showing the media’s ownership. From a hidden watermark in the media from the appearance point of view, general digital watermarking technologies can be divided into two categories: visible watermark technology and invisible watermark technology. Visual watermark technology embeds a watermark into the protected media to declare ownership and deter pirate behavior. In this paper, we propose a reversible visible watermark method, which embeds a binary-imaged watermark into gray-scale images to create a visible watermark. Not using complex calculations, this paper tries to simply change the pixel value to achieve the digital watermark, where our scheme is also against the possible detections with LSB-based manners in use. Furthermore, a reversible steganographic method is used to embed the watermarking information into the watermarking images. The watermark information can then be used to recover the original images. 相似文献
186.
J.-Y. Hsu S.-K. Kuo K.-Y. Wu 《Protection of Metals and Physical Chemistry of Surfaces》2017,53(2):272-278
Iron powder was coated with phosphate and polysiloxanes for anti-corrosion and insulation. Whether these coating layers sustain the hydraulic pressure of compaction was investigated. Electrochemical measurements were applied on the compacts comprising surface-coated iron powders to understand the performance of the coating layers undergone a series of compaction pressure. As phosphate coating was applied, the corrosion resistance was obviously enhanced; nevertheless, as the compaction pressure exceeded a threshold, the corrosion resistance dropped greatly due to the formation of cracks in the phosphate layer, suggesting the phosphate layer was brittle and could not bear high pressure. As a phosphate layer and a polymeric coating layer of amino polysiloxane were in turn applied, the corrosion resistance of the doubly-coated iron powder in the salt bath declined since the ammonium group absorbed chloride ions and deteriorated the anti-corrosion ability. After salt-fog treatment, the compacts with the grafted silane tended to form the rust layer with akaganeite phase while these without grafted silane did not, attesting that the polysiloxane did attract chloride ions. Interestingly, with the existence of polysiloxane, the cracking of the phosphate layer was effectively avoided. The polysiloxane layer could protect the underneath phosphate layer from cracking. Moreover, with the increase of compaction pressure, the corrosion resistance of the doubly-coated iron powder gradually increased due to the densification of the polysiloxane layer, which consequently hindered the chloride ions from diffusion into the surface of the iron particle. 相似文献
187.
The effect of MgF2 and ZnO as additives on the microstructure evolution of a lithium aluminosilicate glass-ceramic is studied by X-ray powder diffraction and X-ray absorption near edge structure. The changes of main, secondary phase development and morphology under different additive concentrations are responsible for the variation in flexural strength. The decreased flexural strength (>50 %) of MgF2-bearing samples can be attributed to the non-uniform microstructure, while the increased flexural strength of the ZnO-doped samples might be due to the decreased residual stress resulting from a reduction of viscosity. In addition, the structural role of Zn ions is changed under different phase evolutions. For highly crystalline samples with commercial-like composition, Zn ions tend to have spinel-like local environments; while in a simplified composition, Zn ions favor hexagonal ZnO-like surroundings. The appearance of significant multiple scattering peaks in the near edge structure indicates Zn ions usually presented in an ordered local environment in high doping level samples (>1 % ZnO or MgF2). 相似文献
188.
189.
This study investigates electromigration in Bi2Te3 thermoelectric (TE) material systems and the effectiveness of the diffusion barrier under current. The Peltier effect on the interfacial reaction was decoupled from the effect of electromigration. After connecting p- and n-type Bi2Te3 to Sn3Ag0.5Cu (SAC305) solders, different current densities were applied at varying temperatures. The Bi2Te3 samples were fabricated by the spark plasma sintering technique, and an electroless nickel-phosphorous (Ni-P) layer was deposited at the solder/TE interfaces. The experimental results confirm the importance of the Ni diffusion barrier in joint reliability. Intermetallic compound layers (Cu,Ni)6Sn5 and NiTe formed at the solder/Ni-P and Ni-P/substrate interfaces, respectively. The experimental results indicate that the mechanism of NiTe and (Cu,Ni)6Sn5 compound growth was dominated by the Peltier effect at high current density. When the current density was low, the growth of NiTe was affected by electromigration but the changes of thickness for (Cu,Ni)6Sn5 were not obvious. 相似文献
190.
People are now living longer because of advances in medical science, resulting in the percentage of the elderly in the population increasing year by year. These older individuals cannot move about like youngsters do. Internet shopping could become one of the most important shopping channels for them. According to related domestic and foreign survey results, this is confirmed by the increased percentage of elderly Internet shoppers. A lot of consumers, however, are still not satisfied with their Internet shopping experiences. Many have had the experience of giving up before completing the purchasing procedure. The key factors included in such procedures are rather complex, and user interfaces are not necessarily well‐designed. Nowadays, most websites are still designed for the convenience of the seller instead of the consumers. Often consumers find that their interfaces are complex and hard to use and that they require a high mental workload. Based on the behavioral model of older Internet consumers and difficulties they have encountered, and after exploring the information provided by shopping websites and evaluating the status of their current interface design, this study proposes an example of a supporting interface design system (SIDS) for the elderly. The effects of the SIDS are verified experimentally. A total of 12 subjects participated in the experiment. The results showed that the SIDS could successfully reduce the time spent by the elderly subjects on inputting data during the shopping process and the number of repetitions and the time spent on searching for, examining, and comparing products. Furthermore, it was also helpful to reduce the mental workload caused by Internet shopping. © 2012 Wiley Periodicals, Inc. 相似文献