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51.
Image mosaic construction is about stitching together a number of images about the same scene to construct a single image with a larger field of view. The majority of the previous work was rooted at the use of a single image-to-image mapping termed planar homography for representing the imaged scene. However, the mapping is applicable only to cases where the imaged scene is either a single planar surface, or very distant from the cameras, or imaged under a pure rotation of the camera, and that greatly limits the range of applications of the mosaicking methods. This paper presents a novel mosaicking solution for scenes that are polyhedral (thus consisting of multiple surfaces) and that are pictured possibly in closed range of the camera. The solution has two major advantages. First, it requires only a few correspondences over the entire scene, not correspondences over every surface patch in it to work. Second, it conquers a seemingly impossible task—warping image data of surfaces that are visible in only one of the input images, which we refer to as the singly visible surfaces, to another viewpoint to constitute the mosaic there. We also provide a detail analysis of what determines whether a singly visible surface could be mosaicked or not. Experimental results on real image data are presented to illustrate the performance of the method. 相似文献
52.
It has been a common consensus that general techniques for stabilization of nonlinear systems are available only for some
special classes of nonlinear systems. Control design for nonlinear systems with uncertain components is usually carried out
on a per system basis, especially when physical control constraints, and certain control performance measures such as optimum
time control are imposed. Elegant adaptive control techniques are difficult to apply to this type of problems. A new neural
network based control design is proposed and presented in this paper to deal with a special class of uncertain nonlinear systems
with multiple inputs. The desired system dynamics are analyzed and utilized in the process of the proposed intelligent control
design. The theoretical results are provided to justify the design procedures. The simulation study is conducted on a second-order
bilinear system with two inputs and uncertainties on its parameters. The simulation results indicate that the proposed design
approach is effective. 相似文献
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56.
Ronald S. Cok John W. Hamer Christopher A. Bower Etienne Menard Salvatore Bonafede 《Journal of the Society for Information Display》2011,19(4):335-341
Abstract— Small integrated circuits of crystalline silicon (chiplets) transfer‐printed onto a flat‐panel‐display substrate provide greatly improved electrical performance and uniformity in active‐matrix organic light‐emitting‐diode (OLED) displays. The integrated circuits are formed in high‐performance crystalline silicon using conventional photolithographic processes and then transfer‐printed onto a substrate using a stamp that transfers hundreds or thousands of chiplets at once. The chiplets are connected to an external controller and to pixel elements using conventional photolithographic substrate processing methods. Active‐matrix OLED (AMOLED) displays using transfer‐printed chiplets have good yields, excellent uniformity, and electrical performance and are thermally robust. 相似文献
57.
Even though there is abundant literature on successful cases of organizations applying knowledge management (KM) measures,
many KM initiatives have failed to achieve their knowledge and business goals. In order to foster decisions about the design
of such initiatives, information is required on success factors and barriers when selecting KM measures. Multi agent-based
simulation (MABS) is suggested as instrument to investigate potential effects of KM measures on dependent variables such as
sharing of knowledge in organizations or business performance. For such a simulation, the concept of knowledge sharing, influencing
factors and their impact on business and knowledge goals are modeled based on an extensive multi-disciplinary literature survey.
An extensive domain model is operationalized in a simulation model which is then further simplified and implemented in a MABS
tool used for a series of experiments contrasting results with/without KM measures, specifically skill and experience management.
Skill management is found highly sensitive with respect to conditions of application and has no significant impact on knowledge
or business goals. Experience management positively impacts knowledge and business goals. Personal documentation leads to
specialist, project debriefings to generalist knowledge workers. Finally, the paper discusses the simulation’s limitations
and further areas of application. 相似文献
58.
Ananda S. Chowdhury Sovira Tan Jianhua Yao Ronald M. Summers 《Pattern recognition letters》2010,31(9):876-883
Colon cancer is the second major cause of cancer related deaths in industrial nations. Computed tomographic colonography (CTC) has emerged in the last decade as a new less invasive colon diagnostic alternative to the usually practiced optical colonoscopy. The overall goal is to increase the effectiveness of virtual endoscopic navigation of the existing computer-aided detection (CAD) system. The colonic/haustral folds serve as important landmarks for various associated tasks in the virtual endoscopic navigation like prone–supine registration, colonic polyp detection and tenia coli extraction. In this paper, we present two different techniques, first in isolation and then in synergism, for the detection of haustral folds. Our input is volumetric computed tomographic colonography (CTC) images. The first method, which uses a combination of heat diffusion and fuzzy c-means algorithm (FCM), has a tendency of over-segmentation. The second method, which employs level sets, suffers from under-segmentation. A synergistic combination, where the output of the first is used as an input for the second, is shown to improve the segmentation quality. Experimental results are presented on digital colon phantoms as well as real patient scans. The combined method has a total erroneous (over-segmentation plus under-segmentation) detection of (6.5 ± 2)% of the total number of folds per colon as compared to (12.5 ± 5)% for the diffusion-FCM-based method and (11.5 ± 3)% for the level set-based method. The p-values obtained from the associated ANOVA tests indicate that the performance improvements are statistically significant. 相似文献
59.
Ronald R. Yager 《Information Sciences》2009,179(22):3908-42
We describe some basic features of the OWA operator. We turn to the problem of determining the weights associated with this operator and particularly the maximal dispersion (entropy) approach. We consider the possibility of using minimization of dispersion. After discussing concerns with both maximization and minimization of dispersion we investigate the possibility of finding an optimal solution intermediate to these extremes. We next consider alternative measures of dispersion. We introduce a fundamental requirement for a measure of dispersion called the Preference for Equal Division. A number of general classes of dispersion measures are provided notable among these are those based on t-norm and t-conorm operators. 相似文献
60.
Ronald P. Loui 《Artificial Intelligence and Law》2016,24(4):371-385
This paper revisits the challenge of Berman and Hafner’s “missing link” paper on representing teleological structure in case-based legal reasoning. It is noted that this was mainly an ontological challenge to represent some of what made legal reasoning distinctive, which was given less attention than factual similarity in the dominant AI and Law paradigm, deriving from HYPO. The response to their paper is noted and briefly evaluated. A parallel is drawn to a new challenge to provide deep structure to the legal context of textual meaning, drawing on the forthcoming work of two Constitutional law scholars who appear to place some faith in the ways of thinking that AI and Law has developed. 相似文献