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151.
The role of nanoparticles and nanofluid additives for biodiesel has gained consistent position in the current trend as they contribute to increase the performance of the engine with lower emission. In addition, additives also help to increase the engine reliability and lifespan. In this work, the effects of canola biodiesel blends of 20% proportions with diesel were investigated at 100% of engine load. The fuel is tested in a multi-cylinder water-cooled direct ignition (DI) engine. There are numerous notable works on nanofluid; however, the addition of TiO2 nanoparticle as additive to produce canola biodiesel fuel is very limited. With the addition of the TiO2 nanoparticle on Canola biodiesel blend in the DI engine, the exhaust property of gases such as CO, HC and NOX is reduced. Furthermore, the combustion characteristics of the engine are improved. The canola biodiesel blends also resulted in lower NOx emission as well as low smoke.  相似文献   
152.
This paper presents an automatic welding control system for the alternating current shield metal arc welding process. A nominal nonlinear mathematical model containing uncertainties such as dead-zone, welding control system saturation, and the identified system parameters is derived. A novel variable structure model reference control scheme is designed to modulate the rate of the electrode feed mechanism, thereby regulating the arc current. The developed controller assures the global reaching condition of the sliding mode of the controlled welding system. In the sliding mode, the electric current error between the plant and the model asymptotically approaches zero. Moreover, the welding system remains insensitive to uncertainties and disturbance as the systems with friction. The simulation and experimental results confirm that the automatic welding control system, based on the proposed model-following variable structure controller, successfully maintains the magnitude of the arc current at the desired value and preserves the stability of the arc length, thereby ensuring excellent welding performance.  相似文献   
153.
This paper presents optimization procedures based on evolutionary algorithms such as the elitist non-dominated sorting genetic algorithm (NSGA-II) and differential evolution (DE) for solving the trajectory planning problem of intelligent robot manipulators with the prevalence of fixed, moving, and oscillating obstacles. The aim is the minimization of a combined objective function, with the constraints being actuator constraints, joint limits, and the obstacle avoidance constraint by considering dynamic equations of motion. Trajectories are defined by B-spline functions. This is a non-linear constrained optimization problem with six objective functions, 31 constraints, and 42 variables. The combined objective function is a weighted balance of transfer time, the mean average of actuator efforts and power, penalty for collision-free motion, singularity avoidance, joint jerks, and joint accelerations. The obstacles are present in the workspace of the robot. The distance between potentially colliding parts is expressed as obstacle avoidance. Further, the motion is represented using translational and rotational matrices. The proposed optimization techniques are explained by applying them to an industrial robot (PUMA 560 robot). Also, the results obtained from NSGA-II and DE are compared and analyzed. This is the first research work which considers all the decision criteria for the trajectory planning of industrial robots with obstacle avoidance. A comprehensive user-friendly general-purpose software package has been developed using VC++ to obtain the optimal solutions using the proposed DE algorithm.  相似文献   
154.
ABSTRACT

In this work, production of hydrocarbon fuel from Mahua oil has been characterised for diesel engine application, by appraising essential fuel processing parameters. As opposed to traditional trans-esterification process, the reported oil was identified by using heterogeneous catalysts, as the latter improves the fuel properties better than the former. Therefore, interest has been taken in utilising heterogeneous catalyst such as Coal fly ash (CFA) for biofuel production process. From the experimental investigation it was observed that performance results such as BTE for B25 blend show marginally lower value to sole fuel at all loads and NOx emission for B100 blend exhibit significantly lower value than sole fuel. Smoke emission for B25 show the increasing trend that of other blends. However, CO, HC emission for B25 shows the marginal increases when compared to the sole fuel and the combustion analysis of B25 blend showed almost similar trend of sole fuel.  相似文献   
155.
ABSTRACT

Materials substitution is an imperative research area. The aim of this research is cost reduction, improved performance on its physical, chemical or mechanical properties like improved strength, reduced weight or in terms of performances. The objective of this paper is to investigate the possibilities to use the steel piston in place of the aluminium alloy piston for small engine applications like portable generator. Aluminium alloy piston, uncoated steel piston, nickel-coated steel piston and hard chrome-coated steel piston are considered. Steel pistons plated had standard thickness and were physically experimented. The thermal analysis like thermal deformation, total and directional heat flux analysis were carried out in ANSYS software. For the outperformed piston, the CFD analyses on contoured particles were carried out with help of ANSYS Fluent software. The CFD analysis on contoured particles includes the static pressure, velocity as well as directional velocity components and path line of contoured particles.  相似文献   
156.
The inherent drawbacks of Co2SnO4 in demonstrating the closer-to-theoretical capacity value behavior and the inadmissible volume-expansion-related capacity fade behavior have been surpassed by choosing a tailor-made material composition of Co2SnO4/SnO2, prepared at two different temperatures such as 400°C and 600°C to obtain residual carbon-containing and carbon-free compositions, respectively. Among the products, carbon-coated Co2SnO4/SnO2 composite exhibits better electrochemical performance compared with that of the carbon-free product mainly because of the beneficial effect of carbon in accommodating the volume-expansion-related issues arising from the alloying/de-alloying mechanism. A combination of conversion reaction and alloying/de-alloying mechanism is found to play a vital role in exhibiting closer-to-theoretical capacity values. In other words, an appreciable specific capacity value of 834 mAh g?1 has been exhibited by Co2SnO4/SnO2 anode containing carbon coating, thus, demonstrating the possibility to improve the electrochemical performance of the title anode through carbon coating, which is realized as a result of the addition of carefully manipulated synthesis conditions.  相似文献   
157.
158.
The gastrointestinal tract is a complex niche and the main port of entry of many pathogens that trigger a wide range of diseases like inflammatory bowel disease (IBD) and colon cancer. Antibodies are effective for treating such diseases, but a system capable of local delivery at the site of the pathology, thus avoiding systemic side effects, is not yet available. Here we report a novel recombinant scFvSIgA1 protein produced by Lactococcus lactis, anchored to the bacterial membrane, which retains its full immuno-recognizing potential. This scFv fragment employed was specific for a colon cancer epitope, epithelial glycoprotein protein-2 (EGP-2). Accordingly L. lactis expressing this chimeric protein was capable of binding cells expressing this epitope. Expression of specific antibodies on bacteria may allow local delivery of anticancer agents produced by such bacteria in conjunction with the antibody and provides a new avenue in the quest for targeted drug delivery.  相似文献   
159.
讨论了基于波信号的解调和人工神经网络的损伤识别算法,以及其在Lamb波信号的应用。Lamb波与损伤相互作用,将修改回波信号,从该信息提取相关的损害信息可用于自动损伤检测。然而,由于该波与损害相互作用的复杂性,波信号的反应是不容易解释。反应的波信号被认为是一个高频率载波信号调制的低频信号。基线减法后,频域卷积和滤波,原来的信号解调成一个新的简单的信号,其与因损伤发生的能量变化有关。随后进行特征提取,通过寻找新信号的局部极大值和所取得的峰值和位置将作为人工神经网络的损伤特性的输入。这种损伤检测验证算法的有效性,通过一个带缺口复合材料层压板缺损模型利用有限元进行验证。对不同缺口深度和位置的反应波信号用于模拟和训练和测试的样本。最后,对网络的精度和泛化能力进行评估,结果是令人满意的。  相似文献   
160.
Group technology (GT) is one of the key issues in the successful implementation of flexible manufacturing systems (FMSs). The success of GT implementation is in the effective formation of part families (PFs) and similarity coefficients measures. Over the past three decades, many similarity coefficients have been proposed, but a better similarity coefficient measure is required. The decision-making process in a manufacturing system often involves uncertainties and ambiguities. Under such circumstances, fuzzy methodologies have proved to be an effective tool for taking fuzziness into consideration. The first part of this paper deals with the fuzzy part-family formation. This was achieved in the following ways: 1. A new similarity coefficient measure has been developed and this coefficient measure is used to form a part-family. 2. A mathematical model that uses this similarity coefficient for solving the part-family formation problems optimally in an FMS is developed. The fuzzy approach has the special advantage of producing more accurate results than conventional clustering and other methods. It not only reveals the specific part family that a part belongs to, but also provides the degree of membership of a part associated with each part family. This will give a balanced work load for the machine. In the second part of this paper, the introduction of the concept of genetic algorithms is proposed to eliminate more job sequences and, finally, the optimum sequence is obtained through the minimum penalty cost. Software is developed and implemented to obtain an optimum sequence and, finally, a numerical example is given as an illustration.  相似文献   
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