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161.
You may wonder what a technology road map is and what purpose it would have. A technology road map is a plan to meet the short- and long-term goals with specific technology. The major benefits of a technology road map would be to 1) help funding agencies reaching a consensus on the set of future needs and the required technologies to meet them 2) devise a mechanism in forecasting technology development 3) develop a framework for planning and coordinating the technology development 4) inform the general public and society about where the robotics and automation is heading.  相似文献   
162.
In this paper, we present visibility-based spatial reasoning techniques for real-time object manipulation in cluttered environments. When a robot is requested to manipulate an object, a collision-free path should be determined to access, grasp, and move the target object. This often requires processing of time-consuming motion planning routines, making real-time object manipulation difficult or infeasible, especially in a robot with a high DOF and/or in a highly cluttered environment. This paper places special emphasis on developing real-time motion planning, in particular, for accessing and removing an object in a cluttered workspace, as a local planner that can be integrated with a general motion planner for improved overall efficiency. In the proposed approach, the access direction of the object to grasp is determined through visibility query, and the removal direction to retrieve the object grasped by the gripper is computed using an environment map. The experimental results demonstrate that the proposed approach, when implemented by graphics hardware, is fast and robust enough to manipulate 3D objects in real-time applications.  相似文献   
163.
A new multi-objective non-Darwinian-type evolutionary computation approach based on learnable evolution model (LEM) is proposed for solving the robot path planning problem. The multi-objective property of this approach is governed by a robust strength Pareto evolutionary algorithm (SPEA) incorporated in the LEM algorithm presented here. Learnable evolution model includes a machine learning method, like the decision trees, that can detect the right directions of the evolution and leads to large improvements in the fitness of the individuals. Several new refiner operators are proposed to improve the objectives of the individuals in the evolutionary process. These objectives are: the path length, the path safety and the path smoothness. A modified integer coding path representation scheme is proposed where the edge-fixing and top-row fixing procedures are performed implicitly. This proposed robot path planning problem solving approach is assessed on eight realistic scenarios in order to verify the performance thereof. Computer simulations reveal that this proposed approach exhibits much higher hypervolume and set coverage in comparison with other similar approaches. The experimental results confirm that the proposed approach performs in the workspaces with a dense set of obstacles in a significant manner.  相似文献   
164.
In this paper, the effect of carbon nanotubes (CNTs) acting as a covering layer on the [Glass/Ni] sample was experimentally investigated. To this end, a 48 nm thick Ni thin film was initially deposited on the glass substrate using a thermal evaporation method. Afterward, a spin-coating method was employed to deposit a thin layer of CNTs on the Ni thin film, thereby forming the [Glass/Ni/CNT] structure. Compared to [Glass/Ni] samples, the presence of CNTs led to 100% and 180% enhancement in the longitudinal Kerr signal of spin-coated samples. Field emission scanning electron microscopy, energy-dispersive x-ray spectroscopy, UV–Vis spectra and vibrating-sample magnetometer analyses were employed to characterize and investigate the morphology, elemental analysis, and optical and magnetic characteristics of the resulting structures. As a covering layer, the CNTs enhanced the absorption of light in the UV–visible wavelength range while also amplifying the interaction of light with the Ni layer without seriously changing other magnetic properties of the structure. Accordingly, using a simple approach, the Kerr signal was amplified more than three times compared to that of an uncovered sample, providing useful applications for magnetic sensors.  相似文献   
165.
This lead article of the special issue discusses conceptual and methodological considerations in studying sexual minority issues, particularly in research conducted by counseling psychologists (including the work represented in this special issue). First, the overarching challenge of conceptualizing and defining sexual minority populations is described. Second, the importance and value of scholarship about sexual minority issues are highlighted. Third, challenges in sexual minority research are outlined, using the articles in this special issue for illustrative purposes, and suggestions are offered for consideration in future research. Finally, the article concludes with a discussion of the ways in which counseling psychologists are uniquely positioned to advance knowledge, practice, and social justice through research on sexual minority issues. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
166.
A fast wavelet based non‐uniform grid generation method is presented for time domain simulation of active semiconductor devices. The proposed approach solves the active part model of the semiconductor device. This approach is used to solve the non‐linear equations of semiconductors on the self‐adaptive grids, obtained by applying wavelet. Non‐uniform mesh size is implemented and controlled by the wavelet coefficients. A fine mesh is used where the unknowns are varying rapidly and a coarser mesh where the unknowns are varying slowly. The energy model is considered for active layer of transistor and its results are compared with those of the classical drift diffusion model. Performance of this method is compared with the conventional finite difference on a uniform mesh. A reduction over 80 percent of unknowns in grid together with good accuracy in simulation is obtained using this non‐uniform mesh while accurate physical behaviour of the device can be predicted. This represents an ongoing effort toward a numerical technique that uses wavelet to solve physical modelling problem of semiconductor devices. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
167.
168.
Microsystem Technologies - In this study, nonlinear dynamic behavior of a capacitive carbon nano-tube switch is investigated considering van der Waals (vdW) force. The carbon nano-tube is...  相似文献   
169.
170.
A short study on bromination of multiwalled carbon nanotubes (MWCNTs) through new and convenient methods was reported. Bromine (Br) is chemically attached on MWCNTs surfaces through electrophilic addition and radical reactions using N-Bromosuccinimide (NBS), NH4NO3/NBS and Br2 under thermal and UV conditions. Functionalized CNTs with Bromine groups, were characterized by Fourier transform infrared spectroscopy (FTIR), thermo gravimetric analysis (TGA), scanning electron microscopy and X-ray diffraction (XRD) methods.  相似文献   
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