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21.
3-O-methylmannose was identified by gas-liquid chromatography-mass spectrometry in the acid hydrolysate of the polysaccharide of Leptospira biflexa Urawa.  相似文献   
22.
The effect of the drying rate of the solvent on microstructure evolution in thin films of immiscible polystyrene/polycarbonate blends was investigated by applying a stepwise change in air velocity. The polymer blend was dissolved in tetrahydrofuran and cast on a glass substrate to form a thin liquid film. The drying rate of the solvent was measured by a gravimetric technique, and the phase-separated structure in the film was observed by optical microscopy. The results indicated that cellular structures of droplet arrays were formed in the phases evolved primarily during the early stage of drying, and the droplets then coalesced in the intermediate stage to form bigger droplets. The size of the first evolved phase decreased with increasing time at a high drying rate, whereas larger droplets were obtained with longer high drying rate regimes. These results suggested that the droplets were induced by secondary phase separation which was strongly affected by the drying rate of the solvent.  相似文献   
23.
In this letter, an effective technique is proposed for improving the computational efficiency of the contraction‐type LP test algorithm, which is an algorithm for finding all solutions of piecewise‐linear resistive circuits. Using the proposed technique, all solutions of a large‐scale problem, where the number of variables is 100 and the number of linear regions is 10100, could be found in less than 10 min using a 360 MHz computer. Copyright 2001 John Wiley & Sons, Ltd.  相似文献   
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25.
In this letter, an efficient algorithm is proposed for finding all solutions of non‐linear (not piecewise‐linear) resistive circuits. This algorithm is based on interval analysis, the dual simplex method, and the contraction methods. By numerical examples, it is shown that the proposed algorithm could find all solutions of systems of 500–700 non‐linear circuit equations in acceptable computation time. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
26.
The ionic conductivity of the ceria-samaria (CeO2-Sm2O3) system is higher than that of yttria-stabilized zirconia and other CeO2-based oxides. In this study, a small amount of alkali-element-doped CeO2-Sm2O3 solid solution was prepared. This solid solution was characterized by measuring the powder density and the chemical composition. Moreover, its electrochemical properties were investigated in the temperature range from 700° to 1000°C. It was found that a small amount of alkali-element-doped CeO2 solid solution enhanced the ionic conductivity. The power density of an oxygen-hydrogen fuel cell for alkali-element-doped CeO2-Sm2O3 ceramics exhibited high values at low temperatures such as 700° to 800°C. It is concluded that the improved fuel cell performance can be attributed to the high stability of this composition in the fuel atmosphere.  相似文献   
27.
We have developed stacked nanocarbon polymer actuators that are composed of several nanocarbon polymer actuator films using nonwoven fabric as insulation layers. The nonwoven fabric prepared through electrospinning methods has extremely-low-density structures, which do not significantly prevent the motions of each nanocarbon actuator layer. Therefore, stacking several thin nanocarbon polymer actuators using nonwoven fabric as insulation layers is expected to increase generated force without decreasing the displacement of a one-layer actuator. We have prepared stacked actuators with one, two, three, four, and seven layers using this method. The displacement and blocking force of these actuators are measured and compared with those of one-layer actuators of different thicknesses. Displacement is weakly dependent on the thickness of the actuator films of the stacked actuators. On the contrary, it decreases considerably as the thickness of the actuator film of the one-layer actuator increases. In both cases, blocking force is proportional to the thickness of actuator films. We have developed a stacked actuator model based on a trilayer actuator model and confirmed the experimental results using the model.  相似文献   
28.
OBJECTIVE: This paper introduces a robust, real-time system for detecting driver lane changes. Background: As intelligent transportation systems evolve to assist drivers in their intended behaviors, the systems have demonstrated a need for methods of inferring driver intentions and detecting intended maneuvers. METHOD: Using a "model tracing" methodology, our system simulates a set of possible driver intentions and their resulting behaviors using a simplification of a previously validated computational model of driver behavior. The system compares the model's simulated behavior with a driver's actual observed behavior and thus continually infers the driver's unobservable intentions from her or his observable actions. RESULTS: For data collected in a driving simulator, the system detects 82% of lane changes within 0.5 s of maneuver onset (assuming a 5% false alarm rate), 93% within 1 s, and 95% before the vehicle moves one fourth of the lane width laterally. For data collected from an instrumented vehicle, the system detects 61% within 0.5 s, 77% within 1 s, and 84% before the vehicle moves one-fourth of the lane width laterally. CONCLUSION: The model-tracing system is the first system to demonstrate high sample-by-sample accuracy at low false alarm rates as well as high accuracy over the course of a lane change with respect to time and lateral movement. APPLICATION: By providing robust real-time detection of driver lane changes, the system shows good promise for incorporation into the next generation of intelligent transportation systems.  相似文献   
29.
ABSTRACT

Manipulation of objects after grasping is an important research topic for robotic hands. In this research, we propose a grip method based on the thenar opposition, which is rarely handled in the framework of conventional precision and power grasps and useful in withdrawing a large torque after the grip, and develop a robotic hand that can realize the grasp as well as normal grasps. To this end, we propose methods to evaluate the thenar opposition and the variety of grasps based on the joint alignment of the thumb. Based on these methods, we determine the kinematic structure of the robotic hand and develop it with gear train transmissions and a soft skin. Experiments are implemented to demonstrate that the robotic hand realizes various grasps and a gripping force sufficient to withstand the torque that opens tightly clamped hand valves.  相似文献   
30.
This paper presents a robust Real-coded evolutionary algorithm. Real-coded evolutionary algorithms (RCEAs), such as real-coded genetic algorithms and evolution strategies, are known as effective methods for function optimization. However, they often fail to find the optimum in case the objective function is multimodal, discrete or high-dimensional. It is also reported that most crossover (or recombination) operators for RCEAs has sampling bias that prevents to find the optimum near the boundary of search space. They like to search the center of search space much more than the other. Therefore, they will not work on functions that have their optima near the boundary of search space. In this paper, we apply two methods, genetic algorithm with search area adaptation (GSA) and toroidal search space conversion (TSC), to the function optimization for improving the robustness of RCEAs. The former method searches adaptively and the latter one removes the sampling bias. Through several experiments, we have confirmed that GSA works adaptively and it shows higher performance, and RCEAs with TSC show effectiveness to find the optima near the boundary of search space.  相似文献   
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