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81.
Flora S. Tsai 《Expert systems with applications》2011,38(5):5330-5335
Blog mining addresses the problem of mining information from blog data. Although mining blogs may share many similarities to Web and text documents, existing techniques need to be reevaluated and adapted for the multidimensional representation of blog data, which exhibit dimensions not present in traditional documents, such as tags. Blog tags are semantic annotations in blogs which can be valuable sources of additional labels for the myriad of blog documents. In this paper, we present a tag-topic model for blog mining, which is based on the Author-Topic model and Latent Dirichlet Allocation. The tag-topic model determines the most likely tags and words for a given topic in a collection of blog posts. The model has been successfully implemented and evaluated on real-world blog data. 相似文献
82.
This paper presents a knowledge exchange framework that can leverage the interoperability among semantically heterogeneous learning objects. With the release of various e-Learning standards, learning contents and digital courses are easy to achieve cross-platform sharing, exchanging, and even reorganizing. However, knowledge sharing in semantic level is still a challenge due to that the learning materials can be presented in any form, such as audios, videos, web pages, and even flash files. The proposed knowledge exchange framework allows users to share their learning materials (also called “learning objects”) in semantic level automatically. This framework contains two methodologies: the first is a semantic mapping between knowledge bases (i.e. ontologies) which have essentially similar concepts, and the second is an ontology-based classification algorithm for sharable learning objects. The proposed algorithm adopts the IMS DRI standard and classifies the sharable learning objects from heterogeneous repositories into a local knowledge base by their inner meaning instead of keyword matching. Significance of this research lies in the semantic inferring rules for ontology mapping and learning objects classification as well as the full automatic processing and self-optimizing capability. Focused on digital learning materials and contrasted to other traditional technologies, the proposed approach has experimentally demonstrated significantly improvement in performance. 相似文献
83.
84.
The majority of the scheduling studies carry a common assumption that machines are available all the time. However, machines may not always be available in the scheduling period due to breakdown or preventive maintenance. Taking preventive maintenance activity into consideration, we dealt with the two-machine flowshop scheduling problem with makespan objective. The preventive maintenance policy in this paper was dependent on the number of finished jobs. The integer programming model was proposed. We combined two recent constructive heuristics, HI algorithm and H algorithm, with Johnson’s algorithm, and named the combined heuristic H&J algorithm. We also developed a constructive heuristic, HD, with time complexities O(n2). Based on the difference in job processing times on two machines, both H&J and HD showed good performance, and the latter was slightly better. The HD algorithm was able to obtain the optimality in 98.88% of cases. We also employed the branch and bound (B&B) algorithm to obtain the optimum. With a good upper bound and a modified lower bound, the proposed B&B algorithm performed significantly effectively. 相似文献
85.
Tsung-Han Tsai Author Vitae Author Vitae Chih-Lun Fang Author Vitae 《Pattern recognition》2009,42(7):1496-1510
In video indexing and summarization, videotext is the very compact and accurate information. Most videotext detection and extraction methods only deal with the static videotext on video frames. Few methods can handle motion videotext efficiently since motion videotext is hardly extracted well. In this paper, we propose a two-directional videotext extractor, called 2DVTE. It is developed as an integrated system to detect, localize and extract the scrolling videotexts. First, the detection method is carried out by edge information to classify regions into text and non-text regions. Second, referring to the localization on scrolling videotext, we propose the two-dimensional projection profile method with horizontal and vertical edge map information. Considering the characteristics of Chinese text, the vertical edge map is used to localize the possible text region and horizontal edge map is used to refine the text region. Third, the extraction method consists of dual mode adaptive thresholding and multi-seed filling algorithm. In the dual mode adaptive thresholding, it produces the non-rectangle pattern to divide the background and foreground more precisely. Referring to the multi-seed filling algorithm, it is based on the consideration of the minimum and maximum length and four directions of the stroke while the previous method only considers the minimum length and two directions of the stroke. With this multi-seed exploitation on strokes, precise seeds are obtained to produce more sophisticated videotext. Considering high throughput and the low complexity issue, we can achieve a real-time system on detecting, localizing, and extracting the scrolling videotexts with only one frame usage instead of multi-frame integration in other literatures. According to the experiment results on various video sequences, all of the horizontal and vertical scrolling videotexts can be extracted precisely. We also make comparisons with other methods. In our analysis, the performance of our algorithm is superior to other existing methods in speed and quality. 相似文献
86.
Since color recording and color representing abilities of various media are very different, color information is often lost or misrepresented in the process of image transmission and reproduction. A Color Management System (CMS) based on iCAM color appearance model is presented in this paper. It can be used either in computer operation system software or application software for obtaining color consistency across different software applications, imaging devices, imaging media and viewing conditions. 相似文献
87.
Yung-Wei Kao Tzu-Han Kao Chi-Yang Tsai Shyan-Ming Yuan 《Computer Standards & Interfaces》2009,31(2):437-453
It is common to browse web pages via mobile devices. However, most of the web pages were designed for desktop computers equipped with big screens. When browsing on mobile devices, a user has to scroll up and down to find the information they want because of the limited screen size. Some commercial products reformat web pages. However, the result pages still contain irrelevant information. We propose a system to personalize users’ mobile web pages. A user can determine which blocks in a web page should be retained. The sequence of these blocks can also be altered according to individual preferences. 相似文献
88.
Wireless local area networks provide high speed data transferring rate to a mobile device. And it is crucial to integrate together two critical issues, the authentication and roaming in heterogeneous networks. For this, Tsai and Chang proposed a SIM-based authentication mechanism for wireless local area networks in 2006. Tsai and Chang's scheme provides an integration method of mobile cellular networks and wireless local area networks. Unfortunately, we found that there are some weaknesses existing in their scheme. In this paper, we propose an improved version for a user roaming in heterogeneous networks. Besides, we also proposed a mobile IP model to provide a better efficiency for a mobile user in WLAN environment. 相似文献
89.
Yih-Kuen Tsay Yu-Fang Chen Ming-Hsien Tsai Kang-Nien Wu Wen-Chin Chan Chi-Jian Luo Jinn-Shu Chang 《Formal Aspects of Computing》2009,21(3):259-275
We introduce a graphical interactive tool, named GOAL, that can assist the user in understanding Büchi automata, linear temporal
logic, and their relation. Büchi automata and linear temporal logic are closely related and have long served as fundamental
building blocks of linear-time model checking. Understanding their relation is instrumental in discovering algorithmic solutions
to model checking problems or simply in using those solutions, e.g., specifying a temporal property directly by an automaton
rather than a temporal formula so that the property can be verified by an algorithm that operates on automata. One main function
of the GOAL tool is translation of a temporal formula into an equivalent Büchi automaton that can be further manipulated visually.
The user may edit the resulting automaton, attempting to optimize it, or simply run the automaton on some inputs to get a
basic understanding of how it operates. GOAL includes a large number of translation algorithms, most of which support past
temporal operators. With the option of viewing the intermediate steps of a translation, the user can quickly grasp how a translation
algorithm works. The tool also provides various standard operations and tests on Büchi automata, in particular the equivalence
test which is essential for checking if a hand-drawn automaton is correct in the sense that it is equivalent to some intended
temporal formula or reference automaton. Several use cases are elaborated to show how these GOAL functions may be combined
to facilitate the learning and teaching of Büchi automata and linear temporal logic.
This work was partially supported by the National Science Council, Taiwan (R.O.C.) under grants NSC94-2213-E-002-089, NSC95-2221-E-002-127,
NSC95-3114-P-001-001-Y02 (iCAST 2006), NSC96-3114-P-001-002-Y (iCAST 2007), and NSC97-2221-E-002-074-MY3. 相似文献
90.
This article investigates the use of femtosecond laser induced surface morphology on silicon wafer surface in water confinement.
Unlike irradiation of silicon surfaces in the air, there are no laser induced periodic structures, but irregular roughness
is formed when the silicon wafer is ablated under water. The unique discovery of a smoothly processed silicon surface in water
confinement under certain laser parameter combinations may help improve laser direct micromachining surface quality in industrial
applications. 相似文献