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131.
We extend the signal space separation (SSS) method to decompose multichannel magnetoencephalographic (MEG) data into regions of interest inside the head. It has been shown that the SSS method can transform MEG data into a signal component generated by neurobiological sources and a noise component generated by external sources outside the head. In this paper, we show that the signal component obtained by the SSS method can be further decomposed by a simple operation into signals originating from deep and superficial sources within the brain. This is achieved by using a scheme that exploits the beamspace methodology that relies on a linear transformation that maximizes the power of the source space of interest. The efficiency and accuracy of the algorithm are demonstrated by experiments utilizing both simulated and real MEG data.  相似文献   
132.
The aim of the present study was to investigate the effects of investment casting and forging process on the microstructure and mechanical properties of friction weldments, AISI 1050–AISI 304. A continuous-drive friction welding device with the automatic control ability of friction time and forging pressure was designed and constructed. Factorial design of experiments was performed to join investment cast AISI 1050 steels and forged AISI 1050 steels with AISI 304 austenitic stainless steel with respect to the optimized process parameters. The joint performance was evaluated by tensile and hardness tests performed parallel and perpendicular to the weld interface. Microstructure of forged parts under friction welding was examined using optical microscopy, scanning electron microscopy, and energy-dispersive spectroscopy. Results of microstructural studies were compared with those of friction welding of investment cast parts. The results reveal that a recrystallized region or a mechanically mixed layer was formed on the AISI 304 side near the weld interface, depending on friction time and friction pressure. Friction welding of forged parts always exhibited higher tensile strength, lower hardness, and more upset than the cast parts.  相似文献   
133.
A goal programming model was developed which attempts to achieve a number of objectives normally desired in the banking industry. The model incorporates objectives relative to providing sufficient liquidity, minimizing risk, maintaining adequate levels of capital, minimizing the cost of capital, maximizing profit and providing reasonable dividends. The constraints on the model relate to pledged assets required by the government, required reserves and limits on certain balance sheet items.

Model validation is accomplished by utilizing data obtained from a commercial bank. The data includes financial information for 1982–1984. The 1982 actual data is utilized by the model to project 1983 and 1984 conditions. These projected numbers are then compared with actual financial data to compare the model's performance with results achieved by management without the use of the model.

Total underachievement of several goals in banking is minimized within the limits of the actual decision environment.  相似文献   

134.
In this paper, we present a parallel system called PHR for computing hierarchical radiosity solutions of complex scenes. The system is targeted for multi-processor architectures with distributed memory. The system evaluates and subdivides the interactions level by level in a breadth first fashion, and the interactions are redistributed at the end of each level to keep load balanced. In order to allow interactions freely travel across processors, all the patch data is replicated on all the processors. Hence, the system favors load balancing at the expense of increased communication volume. However, the results show that the overhead of communication is negligible compared with total execution time. We obtained a speed-up of 25 for 32 processors in our test scenes.  相似文献   
135.
This study covers the geochemical investigations on water and stream sediments to evaluate the influence from the abandoned Kalecik Hg mine. The groundwater samples (S5, S8, S9, WW10) are neutral, slightly alkaline waters which have pH values varying between 7.3 and 7.5. Electrical conductivity (EC) values of groundwaters for spring samples are low (250-300 microS/cm). However, groundwater obtained from a deep well has a higher EC value of 950 microS/cm. Hg concentrations of groundwater samples vary between 0.01 and 0.13 microg/l. Hg concentrations of other water samples taken from mining area from surface waters and adits are between 0.10 and 0.99 microg/l. Adit water (A4) collected at the mine has the highest Hg content of 0.99 microg/l and a pH of 4.4. Trace element concentrations of mine water samples show variable values. As is observed only in MW1 (310 microg/l). A4 was enriched in Cd, Co and Cr and exceed the Turkish drinking water standards (Türk Standartlari Enstitüsü, 1997). Cu concentrations vary between 6.0 and 150 microg/l and are below the Turkish water standards. Mn concentrations in mine waters are between 0.02 and 4.9 mg/l. Only for sample A4 Mn value (4.9 mg/l) exceeds the standard level. Ni was enriched for all of the mine water samples and exceeds the safe standard level (20 microg/l) for drinking water. Of the major ions SO(4) shows a notable increase in this group reaching 650 mg/l that exceeds the drinking water standards. Stream sediment samples have abnormally high values for especially Hg and As, Sb, Ni, Cr metals. With the exception of sample Ss6 of which Hg concentration is 92 mg/kg, all the other samples have Hg contents of higher than 100 mg/kg. Pollution index values are significantly high and vary between 69 and 82 for stream sediment samples.  相似文献   
136.
In this paper, we report on our investigation of the impact of Al doping on the primary physical properties of SILAR fabricated CuO/ZnO composite nanowires. Our characterization on surface and structural analysis showed that we were able to lightly dope the nanocomposites effectively using the SILAR method, which is cost-effective and repeatable. Conductivity of the Al-doped films changed significantly which resulted in greater sensing response for hydration. We utilized artificial sweat solutions to characterize the sensing response of the films and we demonstrated that sensing response almost doubled with Al doping. Transient response of sweat application also showed that response times were less than 10 s for 2% Al-doping. We conclude that Al doping on CuO/ZnO nanocomposites is an excellent candidate to be utilized for hydration sensing through sweat.  相似文献   
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International Journal of Computer Vision - In this work, we introduce Deep Bingham Networks (DBN), a generic framework that can naturally handle pose-related uncertainties and ambiguities arising...  相似文献   
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