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41.
We present and analyze an unsupervised method for Word Sense Disambiguation (WSD). Our work is based on the method presented
by McCarthy et al. in 2004 for finding the predominant sense of each word in the entire corpus. Their maximization algorithm allows weighted
terms (similar words) from a distributional thesaurus to accumulate a score for each ambiguous word sense, i.e., the sense
with the highest score is chosen based on votes from a weighted list of terms related to the ambiguous word. This list is
obtained using the distributional similarity method proposed by Lin Dekang to obtain a thesaurus. In the method of McCarthy
et al., every occurrence of the ambiguous word uses the same thesaurus, regardless of the context where the ambiguous word occurs.
Our method accounts for the context of a word when determining the sense of an ambiguous word by building the list of distributed
similar words based on the syntactic context of the ambiguous word. We obtain a top precision of 77.54% of accuracy versus
67.10% of the original method tested on SemCor. We also analyze the effect of the number of weighted terms in the tasks of
finding the Most Frecuent Sense (MFS) and WSD, and experiment with several corpora for building the Word Space Model. 相似文献
42.
Xi Zhang Author Vitae Wai-Ming Tsang Author Vitae Author Vitae Kazuo Yamazaki Author Vitae 《Computers in Industry》2010,61(7):711-726
Collision detection by machining simulation requires the 3D models of rotating cutters. However, the 3D models of a cutter and holder are not always available. In this paper, a new method is proposed to design an automatic vision-based 3D modeling system, which is able to quickly reconstruct the 3D model of a cutter and holder when they are installed onto the spindle. Only a single camera is mounted on the machine tool to capture the image of the rotating cutter and holder. By viewing the rotating cutter and holder as an object of surface of revolution, the contour of the imaged cutter and holder can be used to reconstruct the 3D model as a stack of circular cross-sections. Then the complete generating function of the cutter and holder can be recovered from the cross-sections. Finally, the 3D model of the cutter is built by rotating the generating function around the spindle axis. The effectiveness and accuracy of the proposed method are verified by experiments on-machine using 12 kinds of cutters and holders, which can satisfy the requirement of collision detection. 相似文献
43.
Parametric interpolation has been widely used in CNC machining because of its advantages over the traditional linear or circular interpolation. Many researchers focused on this field and have made great progress in the specific one, NURBS curve interpolation. These works greatly improved the CNC machining with constant feedrate, confined chord error and limited acceleration/deceleration. However, during CNC machining process, mechanical shocks to machine tool caused by the undesired acceleration/deceleration profile will dramatically deteriorate the surface accuracy and quality of the machined parts. This is, in most occasions, very harmful to machine tools. In this paper, an accurate adaptive NURBS curve interpolator is proposed with consideration of acceleration–deceleration control. The proposed design effectively reduces the machining shocks by constraining the machine tool jerk dynamically. Meanwhile, the constant feedrate is maintained during most time of machining process, and thus high accuracy is achieved while the feedrate profile is greatly smoothed. In order to deal with the sudden change of the acceleration/deceleration around the corner with large curvature, a real-time flexible acceleration/deceleration control scheme is introduced to adjust the feedrate correspondingly. Case study has been taken to verify the feasibility and advantages of the proposed design. 相似文献
44.
Kazuo Yoshida 《Robotics and Autonomous Systems》2010,58(7):833-839
Artifact systems created by humans interact with the surrounding natural world and have a large-scale influence on our human lives. The most creditable concept to this critical issue of scientific and technological development seems to be “System Life” that is an innovative competence to be embodied into any artifact system for creating harmony in the world of natural entities and artifact systems interacting with each other. System life is defined as a seamless system of sensing, processing, activating and expressing mechanisms governed by system life information. This paper introduces a design approach of robots possessing system life. First, this paper presents the concept of system life comparing it with the conventional design methodology of intelligent systems. Second, the paper introduces an intelligent control methodology using the cubic neural network that the author developed in order to cope with unpredicted failures. Finally, the paper presents various intelligent robots, a skiing robot, autonomous soccer robots, a game playing robot, as new concrete artifact systems designed using the system life concept. 相似文献
45.
Shunjiro Ogawa Hideyo Suzuki Masatake Toyoda Yoshio Ito Masahiro Iwaida Hiroko Nonogi Tazu Fuke Kazuo Obara Tadao Adachi Koichi Fujita Makiko Ikuzawa Tetsuo Izumi Takashi Hamano Yukimasa Mitsuhashi Yukio Matsuki 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1979,168(4):293-298
Summary Detection and determination of traces of sulphites in foods was attempted by use of the modified Rankine apparatus and pararosaniline colorimetry. Replacement of alkaline titration reported previously by pararosaniline colorimetry lowered the absolute detection limit from 30 g (titration method) to 2 g. In view of clean analysis, in the color developing system, 0.1 N-sodium hydroxide was used in place of mercuric chloride solution commonly used as an absorbant of sulphites. In order to prevent oxidative decomposition of sulphites during operation, nitrogen gas was used as carrier instead of air. Dimedone and sodium azide were used for the elimination of aldehydes and nitrites, respecitvely, in the sample, which will disturb the color development of sulphites with pararosaniline-formaldehyde reagents. With this improved method, it was possible to determine the residual sulphites in frozen peeled shrimps, sugared beans and other foods with low sulphite contents accurately.
Studies on the Analyses of Sulphites in Foods (IV) 相似文献
Colorimetrische Mikrobestimmung von Sulfiten in Lebensmitteln bei Anwendung der modifizierten IV. Rankine Apparatur
Zusammenfassung Geringe Sulfitmengen in Lebensmitteln (geschälte Garnelen, gezuckerte Bohnen) können colorimetrisch bestimmt werden. Die neuentwickelte Methode beruht auf einer Kombination von colorimetrischer Bestimmung mittels p-Rosanilin und der Bestimmungsmethode nach Rankine. Auf diese Weise lassen sich Gehalte von 2 g noch genau bestimmen. Bei der Farbentwicklung wurde das giftige Quecksilbertetrachlorid durch 0.1 n-NaOH ersetzt, anstelle von Luft Stickstoff als Trägergas verwendet und somit eine Oxydation des Sulfits während der Bestimmung vermieden. Da Nitrit und Aldehyde die Farbentwicklung stören, wurde ihr Einfluß durch Dimedon und Natriumazid ausgeschaltet.
Studies on the Analyses of Sulphites in Foods (IV) 相似文献
46.
Plastic deformation is an unlikely process by which to mould pristine silicon wafers into three-dimensional shapes owing to the inevitable detrimental impact that the resulting mechanically induced defects would have on their electrical properties. However, if one were to find a way of doing so without substantial degradation of these properties, a range of new applications might be opened up. Here we report on the successful plastic deformation of silicon crystal wafers for the preparation of wafers with various shapes. A silicon wafer was set between dies and pressed at high temperatures. One application of shaped wafers is as well-shaped concave silicon crystal lenses or mirrors. The lattice plane of such a crystal lens has a curvature exactly along the surface. A concave spheroidal X-ray lens, in the form of two-dimensional Johann and Johansson's monochromators, is proposed for an X-ray optical component system. We propose and demonstrate a new solar cell system with the concave silicon crystal mirror used as both a solar cell and a focused mirror. This system can make use of the reflected photons from solar cells. 相似文献
47.
Suppose that some particular link in the Internet is currently
congested.
A natural solution is to try to make packets bypass that link.
This can be done by increasing the cost of that link intentionally,
say from a
1 to a
2, since the Internet uses shortest-path
routing. Unfortunately, however, this often causes temporary loops
for packet traveling, called routing loops. In this paper
we show that routing loops can be avoided by increasing the cost
of the link not directly from a
1 to a
2 but through an
intermediate value, a
3, i.e., from a
1 to a
3 and then
to a
2.
We may need several
intermediate values.
We show that in this case
the greedy strategy,
namely, raising the cost as much as possible in each step,
is optimal. 相似文献
48.
Koliya Pulasinghe Keigo Watanabe Kiyotaka Izumi Kazuo Kiguchi 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2004,34(1):293-302
We present a methodology of controlling machines using spoken language commands. The two major problems relating to the speech interfaces for machines, namely, the interpretation of words with fuzzy implications and the out-of-vocabulary (OOV) words in natural conversation, are investigated. The system proposed in this paper is designed to overcome the above two problems in controlling machines using spoken language commands. The present system consists of a hidden Markov model (HMM) based automatic speech recognizer (ASR), with a keyword spotting system to capture the machine sensitive words from the running utterances and a fuzzy-neural network (FNN) based controller to represent the words with fuzzy implications in spoken language commands. Significance of the words, i.e., the contextual meaning of the words according to the machine's current state, is introduced to the system to obtain more realistic output equivalent to users' desire. Modularity of the system is also considered to provide a generalization of the methodology for systems having heterogeneous functions without diminishing the performance of the system. The proposed system is experimentally tested by navigating a mobile robot in real time using spoken language commands. 相似文献
49.
Pure Fe with coverage of 0.5-2.0 nm was deposited on Si (111) 7×7 surfaces by reactive deposition epitaxy (RDE) in an integrated ultrahigh vacuum (UHV) system. Transmission electron microscopy (TEM) confirmed that the as-deposited epitaxial phase exhibits rod-like and equilateral triangular morphology. The as-deposited phase was identified as c-FeSi2 by electron diffraction and high-resolution transmission electron microscopy. It was found that there exists lattice distortion in epitaxial c-FeSi2 phase. Upon annealing at 1073 K, the metastable c-FeSi2 transforms into equilibrium β-FeSi2 phase, the latter inherits completely the morphology of c-FeSi2 phase. Based on RDE and subsequent annealing, a new fabrication technique to grow rod-like semiconducting β-FeSi2 on a Si substrate has been proposed in the present work. 相似文献
50.
Four tufted capuchin monkeys (Cebus apella) were trained to choose from 2 hook-like tools, 1 of which successfully led to collecting food, whereas the other did not because of inappropriate spatial arrangement of the tool and the food. In Experiment 1, all of the monkeys successfully learned the basic task. The monkeys performed successfully with tools of novel colors and shapes in Experiments 2-5. These results demonstrate that the monkeys used the spatial arrangement of the tool and the food as a cue. However, they failed when there were obstacles (Experiment 6) or traps (Experiment 7) on the path along which she monkeys dragged tools. These results may suggest that capuchin monkeys understand the spatial relationship between 2 items, namely, food and. the tool, but do not understand the spatial relationship among 3 items, namely, food, tool, and the environmental condition. The possible role of stimulus generalization is also considered. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献