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991.
The template update problem   总被引:16,自引:0,他引:16  
Template tracking dates back to the 1981 Lucas-Kanade algorithm. One question that has received very little attention, however, is how to update the template so that it remains a good model of the tracked object. We propose a template update algorithm that avoids the "drifting" inherent in the naive algorithm.  相似文献   
992.
We have previously proposed a concept of p-valued-input, q-valued-output threshold logic, namely (p, q)-threshold logic, where 2 qp, 3p, and suggested that p-valued logical networks with costs as low as those of 2-valued logical networks could be obtained, by using the (p, q)-threshold elements with small values of q. In this paper, we describe (1) the condition under which there is a 2-place (p, q)-adic function such that the output-closed set F, generated only from , is (p, q)-logically complete, and (2) the fact that any n-place(p, q)-adic function can be realized using at most O(n) elements in the above F.  相似文献   
993.
Diffraction calculations, such as the angular spectrum method and Fresnel diffractions, are used for calculating scalar light propagation. The calculations are used in wide-ranging optics fields: for example, Computer Generated Holograms (CGHs), digital holography, diffractive optical elements, microscopy, image encryption and decryption, three-dimensional analysis for optical devices and so on. However, increasing demands made by large-scale diffraction calculations have rendered the computational power of recent computers insufficient. We have already developed a numerical library for diffraction calculations using a Graphic Processing Unit (GPU), which was named the GWO library. However, this GWO library is not user-friendly, since it is based on C language and was also run only on a GPU. In this paper, we develop a new C++ class library for diffraction and CGH calculations, which is referred to as a CWO++ library, running on a CPU and GPU. We also describe the structure, performance, and usage examples of the CWO++ library.Program summaryProgram title: CWO++Catalogue identifier: AELL_v1_0Program summary URL: http://cpc.cs.qub.ac.uk/summaries/AELL_v1_0.htmlProgram obtainable from: CPC Program Library, Queen?s University, Belfast, N. IrelandLicensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.htmlNo. of lines in distributed program, including test data, etc.: 109 809No. of bytes in distributed program, including test data, etc.: 4 181 911Distribution format: tar.gzProgramming language: C++Computer: General computers and general computers with NVIDIA GPUsOperating system: Windows XP, Vista, 7Has the code been vectorized or parallelized?: Yes. 1 core processor used in CPU and many cores in GPU.RAM: 256 M bytesClassification: 18External routines: CImg, FFTWNature of problem: The CWO++ library provides diffraction calculations which are useful for Computer Generated Holograms (CGHs), digital holography, diffractive optical elements, microscopy, image encryption and decryption and three-dimensional analysis for optical devices.Solution method: FFT-based diffraction calculations, computer generated holograms by direct integration.Running time: The sample runs provided take approximately 5 minutes for the C++ version and 5 seconds for the C++ with GPUs version.  相似文献   
994.
Myxococcus xanthus contains two genes (lonV and lonD) homologous to the Escherichia coli lon gene for an ATP-dependent protease. We found that the lonD gene encodes a 90-kDa protein consisting of 827 amino acid residues. The lonD gene product shows 49, 48, and 52% sequence identity to the products of the M. xanthus lonV, E. coli lon, and Bacillus brevis lon genes, respectively. When a lonD-lacZ fusion was used, lonD was expressed during both vegetative growth and development. However, while lonD-disrupted strains were able to grow normally vegetatively, the development of M. xanthus was found to be arrested at an early stage in these strains. The mutant strains were able to form neither fruiting bodies nor myxospores.  相似文献   
995.
This paper presents an appearance-based method for estimating head direction that automatically adapts to individual scenes. Appearance-based estimation methods usually require a ground-truth dataset taken from a scene that is similar to test video sequences. However, it is almost impossible to acquire many manually labeled head images for each scene. We introduce an approach that automatically aggregates labeled head images by inferring head direction labels from walking direction. Furthermore, in order to deal with large variations that occur in head appearance even within the same scene, we introduce an approach that segments a scene into multiple regions according to the similarity of head appearances. Experimental results demonstrate that our proposed method achieved higher accuracy in head direction estimation than conventional approaches that use a scene-independent generic dataset.  相似文献   
996.
In order to develop a proof procedure of multi-agent autoepistemic Logic (MAEL), a natural framework to formalize belief and reasoning including inheritance, persistence, and causality, we introduce a method that translates a MAEL theory into a logic program with integrity constraints. It is proved that there exists one-to-one correspondence between extensions of a MAEL theory and stable models of a logic program translated from it. Our approach has the following advantages: (1) We can obtain all extensions of a MAEL theory if we compute all stable models of the translated logic program. (2) We can fully use efficient techniques or systems for computing stable models of a logic program. We also investigate the properties of reasoning in MAEL through this translation. The fact that the extension computing problem can be reduced to the stable model computing problem implies that there are close relationships between MAEL and other formalizations of nonmonotonic reasoning.  相似文献   
997.
Linked Open Data (LOD) is recently attracting attention as a vast amount of distributed knowledge base on the Web. Thus, semi-structured data such as tables and hierarchical data in several domains have been triplified to the LOD. Moreover, triplification of unstructured data such as text and sensor data is actively studied in the research area. We thus developed a Web API for extracting triples from natural sentences, which is useful for the promotion of the LOD. In this paper, we first describe the service specification, its technical background, and the evaluation of the current extraction accuracy, and then introduce several use cases of the service. Although this service adopts a novel combination of a method using ontology-based rules and a machine learning method using Conditional Random Field based on a probability distribution, the main contributions are in the practical aspect, that is, mashup of several natural language processing (NLP) techniques for the text triplification, and its deployment as a public Web API, so that non-experts of NLP can easily use it.  相似文献   
998.
Paterson and Quaglia (SCN 2010) proposed the concept of time-specific encryption (TSE) and its efficient constructions. TSE is a type of public-key encryption with an additional functionality where an encryptor can specify a suitable time interval, meaning that the ciphertexts may only be decrypted within this time interval. In this work, we propose a new methodology for designing efficient TSE schemes by using forward-secure encryption (FSE), and based on this methodology, we present a specific TSE scheme using Boneh–Boyen–Goh FSE, and a generic construction from any FSE. Our proposed TSE schemes are practical in all aspects with regard to computational costs and data sizes. The sizes of the ciphertext and the public parameter in our schemes are significantly smaller than those in previous schemes in an asymptotic sense.  相似文献   
999.
We have developed very flexible and lightweight LED-embedded ribbons in which LED-mounted printed circuit board (PCB) pieces are mounted and soldered to ribbons with the copper wires of power lines to apply them to the complicated three dimensional shapes of ceilings, walls, and furniture in rooms and provide higher levels of safety during earthquakes. Since it has been difficult to integrate LEDs in flexible ribbons and not only mount them on flat substrates but on bendable ribbons, we developed a new structure for LED-embedded ribbons and their fabrication process using a reel to reel mounting machine. A 2-cm wide ribbon with copper power lines on both sides was first constructed for the fabrication process of LED-mounted ribbons and then 5 × 20 mm LED mounted PCB pieces were mounted and soldered to the power lines of the ribbon. The ribbon was pulled under an optimal tension of 3.16 N to flatten the ribbon in the mounting process and the PCB pieces were pushed onto the ribbon with a rib height of 5 mm to strongly connect the pieces to the ribbon. The LED-embedded ribbon we constructed was 1.2 m long and very lightweight because it only weighed 7 g/m. The fabricated device had enough luminance of 96 lx for home and office lighting and could be installed on complicated surfaces such as adhering it to ceilings and the edges between ceilings and walls because our LED ribbon could be bent to a diameter of 5 mm. Our LED-embedded ribbon structure and assembly tool should provide new types of highly bendable and light-weight lighting for complicated three dimensional surfaces and safety during earthquakes.  相似文献   
1000.
This paper presents a proposal of a general framework that explicitly models local information and global information in a conditional random field. The proposed method extracts global image features as well as local ones and uses them to predict the scene of the input image. Scene-based top-down information is generated based on the predicted scene. It represents a global spatial configuration of labels and category compatibility over an image. Incorporation of the global information helps to resolve local ambiguities and achieves locally and globally consistent image recognition. In spite of the model's simplicity, the proposed method demonstrates good performance in image labeling of two datasets.  相似文献   
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