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81.
Neural Processing Letters - Recently, m-polar fuzzy graph (mPF graph) becomes a growing research topic as the generalization of fuzzy graph. In this paper, at first mPF path, mPF cycle in an mPF...  相似文献   
82.
83.
Present investigations deal with development of a novel variable compression ratio (VCR) mechanism and its implementation in a small and relatively large size single-cylinder engines. Operation of this mechanism is found to be smooth and effective in the running condition of the engine as well. This mechanism, when incorporated in the small size spark ignition HONDA engine, portrayed improvement in engine performance with increment in compression ratio (CR) for petrol and kerosene. Their respective optimum CRs 5.02 (petrol) and 5.27 (kerosene) are higher than the base value 4.8. In case of large size KIRLOSKAR engine, the present VCR mechanism is found to be useful while operating with liquefied petroleum gas (LPG), where measurements showed that combustion duration is lower with LPG for CR 9.79 as compared with base value 9.0. The present experiments clearly demonstrate the usefulness of VCR mechanism in improving engine performance for a given fuel and broadening the range of alternative fuels burnt in the engine. Ease of fabrication, simplicity in installation, accessibility in troubleshooting and smooth run-time alterations are the advantages with the current novel mechanism.  相似文献   
84.
This paper suggests a combined novel control strategy for DFIG based wind power systems (WPS) under both nonlinear and unbalanced load conditions. The combined control approach is designed by coordinating the machine side converter (MSC) and the load side converter (LSC) control approaches. The proposed MSC control approach is designed by using a model predictive control (MPC) approach to generate appropriate real and reactive power. The MSC controller selects an appropriate rotor voltage vector by using a minimized optimization cost function for the converter operation. It shows its superiority by eliminating the requirement of transformation, switching table, and the PWM techniques. The proposed MSC reduces the cost, complexity, and computational burden of the WPS. On the other hand, the LSC control approach is designed by using a mathematical morphological technique (MMT) for appropriate DC component extraction. Due to the appropriate DC-component extraction, the WPS can compensate the harmonics during both steady and dynamic states. Further, the LSC controller also provides active power filter operation even under the shutdown of WPS condition. To verify the applicability of coordinated control operation, the WPS-based microgrid system is tested under various test conditions. The proposed WPS is designed by using a MATLAB/Simulink software.  相似文献   
85.
This paper presents a combined control and modulation technique to enhance the power quality (PQ) and power reliability (PR) of a hybrid energy system (HES) through a single-phase 11-level cascaded H-bridge inverter (11-CHBI). The controller and inverter specifically regulate the HES and meet the load demand. To track optimum power, a Modified Perturb and Observe (MP&O) technique is used for HES. Ultra-capacitor (UCAP) based energy storage device and a novel current control strategy are proposed to provide additional active power support during both voltage sag and swell conditions. For an improved PQ and PR, a two-way current control strategy such as the main controller (MC) and auxiliary controller (AC) is suggested for the 11-CHBI operation. MC is used to regulate the active current component through the fuzzy controller (FC), and AC is used to regulate the dc-link voltage of CHBI through a neural network-based PI controller (ANN-PI). By tracking the reference signals from MC and AC, a novel hybrid pulse width modulation (HPWM) technique is proposed for the 11-CHBI operation. To justify and analyze the MATLAB/Simulink software-based designed model, the robust controller performance is tested through numerous steady-state and dynamic state case studies.  相似文献   
86.
Wireless Personal Communications - The proposed beamforming model exploits the underlying sparseness of the adaptive filter as impulse response of wireless channel shows some extent of sparse...  相似文献   
87.
Analog Integrated Circuits and Signal Processing - Electronic circuits operating in the radiation intensive environment like space, are subject to a barrage of cosmic particles like neutrons,...  相似文献   
88.
Delineation of groundwater potential zones (GWPZ) has been performed for a coastal groundwater basin of eastern India. The groundwater potential zone index (GWPZI) map is generated by using Analytic Hierarchy Process (AHP) from different influencing features, e.g., Land Use/Land Cover (LU/LC), soil (S), geomorphology (GM), hydrogeology (HG), surface geology (SG), recharge rate (RR), drainage density (DD), rainfall (RF), slope (Sl), surface water bodies (SW), lineament density (LD), and Normalized Difference Vegetative Index (NDVI). Recharge rate values are estimated from hydrological water balance model. Overlay weighted sum method is used to integrate all thematic feature maps to generate GWPZ map of the study area. Four zones have been identified for the coastal groundwater basin [very good: 36.39 % (273.53 km2, good: 43.57 % (327.47 km2), moderate: 18.27 % (137.30 km2), and poor: 1.77 % (13.27 km2)]. Areas in north to south-west and south-east direction show very good GWPZ due to the presence of low drainage density. GWPZ map and well yield values show good agreement. Sensitivity analysis reveals that exclusion/absence of rainfall and lineament density increases the poor groundwater potential zones. Omission of hydrogeology, soils, surface geology, and NDVI show maximum increase in good GWPZ. Obtained GWPZ map can be utilized effectively for planning of sustainable agriculture. This analysis demonstrates the potential applicability of the methodology for a general coastal groundwater basin.  相似文献   
89.
An experimental study was carried out to investigate the dry sliding friction and wear characteristics of woven glass epoxy composites filled with Al particulates sliding against steel using a pin-on-disc tribometer. The glass fiber weight fraction was kept constant at 60 wt% and Al wt% varied as 0, 5, 10, and 15%. The composite was fabricated by a hand lay-up technique followed by light compression molding. Friction and wear behavior under dry sliding condition are presented as a function of sliding speed varying between 1–5 m/s and normal load ranging between 10–40 N. Friction characteristics of composites depend strongly on a combination of filler content, sliding speed and load. Wear loss increases with both sliding speed and load. Incorporation of a smaller amount of Al filler reduces wear loss compared to un-filled glass epoxy composites. An attempt has also been made to observe the distribution of fiber and Al particles in the composite, and to correlate the wear behavior using Scanning Electron Microscopy (SEM) observations.  相似文献   
90.
Nanogold-imprinted starch bionanocomposites of various compositions were synthesized by “one-pot reaction” with in situ generation of nanogold. Bionanocomposites were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, field emission scanning electron microscope and high-resolution transmission electron microscope. The electrical conductivity of nanocomposites was enhanced because of dispersion of nanogold in the starch. Antimicrobial activity of starch was increased due to incorporation of nanogold. The bionanocomposites were resistant towards dilute acid and alkali with little scarification in biodegradable properties. The enhanced thermal, gas barrier and antimicrobial properties may enable the synthesized materials for packaging applications.  相似文献   
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